guix.texi 1.4 MB

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  1. \input texinfo
  2. @c -*-texinfo-*-
  3. @c %**start of header
  4. @setfilename guix.info
  5. @documentencoding UTF-8
  6. @settitle GNU Guix Reference Manual
  7. @c %**end of header
  8. @include version.texi
  9. @c Identifier of the OpenPGP key used to sign tarballs and such.
  10. @set OPENPGP-SIGNING-KEY-ID 27D586A4F8900854329FF09F1260E46482E63562
  11. @set OPENPGP-SIGNING-KEY-URL https://sv.gnu.org/people/viewgpg.php?user_id=127547
  12. @c Base URL for downloads.
  13. @set BASE-URL https://ftp.gnu.org/gnu/guix
  14. @c The official substitute server used by default.
  15. @set SUBSTITUTE-SERVER-1 ci.guix.gnu.org
  16. @set SUBSTITUTE-SERVER-2 bordeaux.guix.gnu.org
  17. @set SUBSTITUTE-URLS https://@value{SUBSTITUTE-SERVER-1} https://@value{SUBSTITUTE-SERVER-2}
  18. @copying
  19. Copyright @copyright{} 2012-2022 Ludovic Courtès@*
  20. Copyright @copyright{} 2013, 2014, 2016 Andreas Enge@*
  21. Copyright @copyright{} 2013 Nikita Karetnikov@*
  22. Copyright @copyright{} 2014, 2015, 2016 Alex Kost@*
  23. Copyright @copyright{} 2015, 2016 Mathieu Lirzin@*
  24. Copyright @copyright{} 2014 Pierre-Antoine Rault@*
  25. Copyright @copyright{} 2015 Taylan Ulrich Bayırlı/Kammer@*
  26. Copyright @copyright{} 2015, 2016, 2017, 2019, 2020, 2021 Leo Famulari@*
  27. Copyright @copyright{} 2015, 2016, 2017, 2018, 2019, 2020, 2021 Ricardo Wurmus@*
  28. Copyright @copyright{} 2016 Ben Woodcroft@*
  29. Copyright @copyright{} 2016, 2017, 2018, 2021 Chris Marusich@*
  30. Copyright @copyright{} 2016, 2017, 2018, 2019, 2020, 2021, 2022 Efraim Flashner@*
  31. Copyright @copyright{} 2016 John Darrington@*
  32. Copyright @copyright{} 2016, 2017 Nikita Gillmann@*
  33. Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Jan Nieuwenhuizen@*
  34. Copyright @copyright{} 2016, 2017, 2018, 2019, 2020, 2021 Julien Lepiller@*
  35. Copyright @copyright{} 2016 Alex ter Weele@*
  36. Copyright @copyright{} 2016, 2017, 2018, 2019, 2020, 2021 Christopher Baines@*
  37. Copyright @copyright{} 2017, 2018, 2019 Clément Lassieur@*
  38. Copyright @copyright{} 2017, 2018, 2020, 2021 Mathieu Othacehe@*
  39. Copyright @copyright{} 2017 Federico Beffa@*
  40. Copyright @copyright{} 2017, 2018 Carlo Zancanaro@*
  41. Copyright @copyright{} 2017 Thomas Danckaert@*
  42. Copyright @copyright{} 2017 humanitiesNerd@*
  43. Copyright @copyright{} 2017, 2021 Christine Lemmer-Webber@*
  44. Copyright @copyright{} 2017, 2018, 2019, 2020, 2021, 2022 Marius Bakke@*
  45. Copyright @copyright{} 2017, 2019, 2020 Hartmut Goebel@*
  46. Copyright @copyright{} 2017, 2019, 2020, 2021 Maxim Cournoyer@*
  47. Copyright @copyright{} 2017–2022 Tobias Geerinckx-Rice@*
  48. Copyright @copyright{} 2017 George Clemmer@*
  49. Copyright @copyright{} 2017 Andy Wingo@*
  50. Copyright @copyright{} 2017, 2018, 2019, 2020 Arun Isaac@*
  51. Copyright @copyright{} 2017 nee@*
  52. Copyright @copyright{} 2018 Rutger Helling@*
  53. Copyright @copyright{} 2018, 2021 Oleg Pykhalov@*
  54. Copyright @copyright{} 2018 Mike Gerwitz@*
  55. Copyright @copyright{} 2018 Pierre-Antoine Rouby@*
  56. Copyright @copyright{} 2018, 2019 Gábor Boskovits@*
  57. Copyright @copyright{} 2018, 2019, 2020 Florian Pelz@*
  58. Copyright @copyright{} 2018 Laura Lazzati@*
  59. Copyright @copyright{} 2018 Alex Vong@*
  60. Copyright @copyright{} 2019 Josh Holland@*
  61. Copyright @copyright{} 2019, 2020 Diego Nicola Barbato@*
  62. Copyright @copyright{} 2019 Ivan Petkov@*
  63. Copyright @copyright{} 2019 Jakob L. Kreuze@*
  64. Copyright @copyright{} 2019 Kyle Andrews@*
  65. Copyright @copyright{} 2019 Alex Griffin@*
  66. Copyright @copyright{} 2019, 2020, 2021, 2022 Guillaume Le Vaillant@*
  67. Copyright @copyright{} 2020 Liliana Marie Prikler@*
  68. Copyright @copyright{} 2019, 2020, 2021, 2022 Simon Tournier@*
  69. Copyright @copyright{} 2020 Wiktor Żelazny@*
  70. Copyright @copyright{} 2020 Damien Cassou@*
  71. Copyright @copyright{} 2020 Jakub Kądziołka@*
  72. Copyright @copyright{} 2020 Jack Hill@*
  73. Copyright @copyright{} 2020 Naga Malleswari@*
  74. Copyright @copyright{} 2020, 2021 Brice Waegeneire@*
  75. Copyright @copyright{} 2020 R Veera Kumar@*
  76. Copyright @copyright{} 2020, 2021 Pierre Langlois@*
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  78. Copyright @copyright{} 2020 André Batista@*
  79. Copyright @copyright{} 2020, 2021 Alexandru-Sergiu Marton@*
  80. Copyright @copyright{} 2020 raingloom@*
  81. Copyright @copyright{} 2020 Daniel Brooks@*
  82. Copyright @copyright{} 2020 John Soo@*
  83. Copyright @copyright{} 2020 Jonathan Brielmaier@*
  84. Copyright @copyright{} 2020 Edgar Vincent@*
  85. Copyright @copyright{} 2021 Maxime Devos@*
  86. Copyright @copyright{} 2021 B. Wilson@*
  87. Copyright @copyright{} 2021 Xinglu Chen@*
  88. Copyright @copyright{} 2021 Raghav Gururajan@*
  89. Copyright @copyright{} 2021 Domagoj Stolfa@*
  90. Copyright @copyright{} 2021 Hui Lu@*
  91. Copyright @copyright{} 2021 pukkamustard@*
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  93. Copyright @copyright{} 2021 Josselin Poiret@*
  94. Copyright @copyright{} 2021 Andrew Tropin@*
  95. Copyright @copyright{} 2021 Sarah Morgensen@*
  96. Copyright @copyright{} 2021 Josselin Poiret@*
  97. Copyright @copyright{} 2022 Remco van 't Veer@*
  98. Copyright @copyright{} 2022 Aleksandr Vityazev@*
  99. Permission is granted to copy, distribute and/or modify this document
  100. under the terms of the GNU Free Documentation License, Version 1.3 or
  101. any later version published by the Free Software Foundation; with no
  102. Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
  103. copy of the license is included in the section entitled ``GNU Free
  104. Documentation License''.
  105. @end copying
  106. @dircategory System administration
  107. @direntry
  108. * Guix: (guix). Manage installed software and system configuration.
  109. * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
  110. * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
  111. * guix pull: (guix)Invoking guix pull. Update the list of available packages.
  112. * guix system: (guix)Invoking guix system. Manage the operating system configuration.
  113. * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
  114. @end direntry
  115. @dircategory Software development
  116. @direntry
  117. * guix shell: (guix)Invoking guix shell. Creating software environments.
  118. * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
  119. * guix build: (guix)Invoking guix build. Building packages.
  120. * guix pack: (guix)Invoking guix pack. Creating binary bundles.
  121. @end direntry
  122. @titlepage
  123. @title GNU Guix Reference Manual
  124. @subtitle Using the GNU Guix Functional Package Manager
  125. @author The GNU Guix Developers
  126. @page
  127. @vskip 0pt plus 1filll
  128. Edition @value{EDITION} @*
  129. @value{UPDATED} @*
  130. @insertcopying
  131. @end titlepage
  132. @contents
  133. @c *********************************************************************
  134. @node Top
  135. @top GNU Guix
  136. This document describes GNU Guix version @value{VERSION}, a functional
  137. package management tool written for the GNU system.
  138. @c TRANSLATORS: You can replace the following paragraph with information on
  139. @c how to join your own translation team and how to report issues with the
  140. @c translation.
  141. This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
  142. GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
  143. Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
  144. Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
  145. Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
  146. would like to translate it in your native language, consider joining
  147. @uref{https://translate.fedoraproject.org/projects/guix/documentation-manual,
  148. Weblate} (@pxref{Translating Guix}).
  149. @menu
  150. * Introduction:: What is Guix about?
  151. * Installation:: Installing Guix.
  152. * System Installation:: Installing the whole operating system.
  153. * Getting Started:: Your first steps.
  154. * Package Management:: Package installation, upgrade, etc.
  155. * Channels:: Customizing the package collection.
  156. * Development:: Guix-aided software development.
  157. * Programming Interface:: Using Guix in Scheme.
  158. * Utilities:: Package management commands.
  159. * System Configuration:: Configuring the operating system.
  160. * Home Configuration:: Configuring the home environment.
  161. * Documentation:: Browsing software user manuals.
  162. * Installing Debugging Files:: Feeding the debugger.
  163. * Using TeX and LaTeX:: Typesetting.
  164. * Security Updates:: Deploying security fixes quickly.
  165. * Bootstrapping:: GNU/Linux built from scratch.
  166. * Porting:: Targeting another platform or kernel.
  167. * Contributing:: Your help needed!
  168. * Acknowledgments:: Thanks!
  169. * GNU Free Documentation License:: The license of this manual.
  170. * Concept Index:: Concepts.
  171. * Programming Index:: Data types, functions, and variables.
  172. @detailmenu
  173. --- The Detailed Node Listing ---
  174. Introduction
  175. * Managing Software the Guix Way:: What's special.
  176. * GNU Distribution:: The packages and tools.
  177. Installation
  178. * Binary Installation:: Getting Guix running in no time!
  179. * Requirements:: Software needed to build and run Guix.
  180. * Running the Test Suite:: Testing Guix.
  181. * Setting Up the Daemon:: Preparing the build daemon's environment.
  182. * Invoking guix-daemon:: Running the build daemon.
  183. * Application Setup:: Application-specific setup.
  184. * Upgrading Guix:: Upgrading Guix and its build daemon.
  185. Setting Up the Daemon
  186. * Build Environment Setup:: Preparing the isolated build environment.
  187. * Daemon Offload Setup:: Offloading builds to remote machines.
  188. * SELinux Support:: Using an SELinux policy for the daemon.
  189. System Installation
  190. * Limitations:: What you can expect.
  191. * Hardware Considerations:: Supported hardware.
  192. * USB Stick and DVD Installation:: Preparing the installation medium.
  193. * Preparing for Installation:: Networking, partitioning, etc.
  194. * Guided Graphical Installation:: Easy graphical installation.
  195. * Manual Installation:: Manual installation for wizards.
  196. * After System Installation:: When installation succeeded.
  197. * Installing Guix in a VM:: Guix System playground.
  198. * Building the Installation Image:: How this comes to be.
  199. Manual Installation
  200. * Keyboard Layout and Networking and Partitioning:: Initial setup.
  201. * Proceeding with the Installation:: Installing.
  202. Package Management
  203. * Features:: How Guix will make your life brighter.
  204. * Invoking guix package:: Package installation, removal, etc.
  205. * Substitutes:: Downloading pre-built binaries.
  206. * Packages with Multiple Outputs:: Single source package, multiple outputs.
  207. * Invoking guix gc:: Running the garbage collector.
  208. * Invoking guix pull:: Fetching the latest Guix and distribution.
  209. * Invoking guix time-machine:: Running an older revision of Guix.
  210. * Inferiors:: Interacting with another revision of Guix.
  211. * Invoking guix describe:: Display information about your Guix revision.
  212. * Invoking guix archive:: Exporting and importing store files.
  213. Substitutes
  214. * Official Substitute Servers:: One particular source of substitutes.
  215. * Substitute Server Authorization:: How to enable or disable substitutes.
  216. * Getting Substitutes from Other Servers:: Substitute diversity.
  217. * Substitute Authentication:: How Guix verifies substitutes.
  218. * Proxy Settings:: How to get substitutes via proxy.
  219. * Substitution Failure:: What happens when substitution fails.
  220. * On Trusting Binaries:: How can you trust that binary blob?
  221. Channels
  222. * Specifying Additional Channels:: Extending the package collection.
  223. * Using a Custom Guix Channel:: Using a customized Guix.
  224. * Replicating Guix:: Running the @emph{exact same} Guix.
  225. * Channel Authentication:: How Guix verifies what it fetches.
  226. * Channels with Substitutes:: Using channels with available substitutes.
  227. * Creating a Channel:: How to write your custom channel.
  228. * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
  229. * Declaring Channel Dependencies:: How to depend on other channels.
  230. * Specifying Channel Authorizations:: Defining channel authors authorizations.
  231. * Primary URL:: Distinguishing mirror to original.
  232. * Writing Channel News:: Communicating information to channel's users.
  233. Development
  234. * Invoking guix shell:: Spawning one-off software environments.
  235. * Invoking guix environment:: Setting up development environments.
  236. * Invoking guix pack:: Creating software bundles.
  237. * The GCC toolchain:: Working with languages supported by GCC.
  238. * Invoking guix git authenticate:: Authenticating Git repositories.
  239. Programming Interface
  240. * Package Modules:: Packages from the programmer's viewpoint.
  241. * Defining Packages:: Defining new packages.
  242. * Defining Package Variants:: Customizing packages.
  243. * Build Systems:: Specifying how packages are built.
  244. * Build Phases:: Phases of the build process of a package.
  245. * Build Utilities:: Helpers for your package definitions and more.
  246. * Search Paths:: Declaring search path environment variables.
  247. * The Store:: Manipulating the package store.
  248. * Derivations:: Low-level interface to package derivations.
  249. * The Store Monad:: Purely functional interface to the store.
  250. * G-Expressions:: Manipulating build expressions.
  251. * Invoking guix repl:: Programming Guix in Guile.
  252. Defining Packages
  253. * package Reference:: The package data type.
  254. * origin Reference:: The origin data type.
  255. Utilities
  256. * Invoking guix build:: Building packages from the command line.
  257. * Invoking guix edit:: Editing package definitions.
  258. * Invoking guix download:: Downloading a file and printing its hash.
  259. * Invoking guix hash:: Computing the cryptographic hash of a file.
  260. * Invoking guix import:: Importing package definitions.
  261. * Invoking guix refresh:: Updating package definitions.
  262. * Invoking guix style:: Styling package definitions.
  263. * Invoking guix lint:: Finding errors in package definitions.
  264. * Invoking guix size:: Profiling disk usage.
  265. * Invoking guix graph:: Visualizing the graph of packages.
  266. * Invoking guix publish:: Sharing substitutes.
  267. * Invoking guix challenge:: Challenging substitute servers.
  268. * Invoking guix copy:: Copying to and from a remote store.
  269. * Invoking guix container:: Process isolation.
  270. * Invoking guix weather:: Assessing substitute availability.
  271. * Invoking guix processes:: Listing client processes.
  272. Invoking @command{guix build}
  273. * Common Build Options:: Build options for most commands.
  274. * Package Transformation Options:: Creating variants of packages.
  275. * Additional Build Options:: Options specific to 'guix build'.
  276. * Debugging Build Failures:: Real life packaging experience.
  277. System Configuration
  278. * Using the Configuration System:: Customizing your GNU system.
  279. * operating-system Reference:: Detail of operating-system declarations.
  280. * File Systems:: Configuring file system mounts.
  281. * Mapped Devices:: Block device extra processing.
  282. * Swap Space:: Backing RAM with disk space.
  283. * User Accounts:: Specifying user accounts.
  284. * Keyboard Layout:: How the system interprets key strokes.
  285. * Locales:: Language and cultural convention settings.
  286. * Services:: Specifying system services.
  287. * Setuid Programs:: Programs running with root privileges.
  288. * X.509 Certificates:: Authenticating HTTPS servers.
  289. * Name Service Switch:: Configuring libc's name service switch.
  290. * Initial RAM Disk:: Linux-Libre bootstrapping.
  291. * Bootloader Configuration:: Configuring the boot loader.
  292. * Invoking guix system:: Instantiating a system configuration.
  293. * Invoking guix deploy:: Deploying a system configuration to a remote host.
  294. * Running Guix in a VM:: How to run Guix System in a virtual machine.
  295. * Defining Services:: Adding new service definitions.
  296. Home Environment Configuration
  297. * Invoking guix home:: Instantiating a home environment configuration.
  298. Services
  299. * Base Services:: Essential system services.
  300. * Scheduled Job Execution:: The mcron service.
  301. * Log Rotation:: The rottlog service.
  302. * Networking Setup:: Setting up network interfaces.
  303. * Networking Services:: Firewall, SSH daemon, etc.
  304. * Unattended Upgrades:: Automated system upgrades.
  305. * X Window:: Graphical display.
  306. * Printing Services:: Local and remote printer support.
  307. * Desktop Services:: D-Bus and desktop services.
  308. * Sound Services:: ALSA and Pulseaudio services.
  309. * Database Services:: SQL databases, key-value stores, etc.
  310. * Mail Services:: IMAP, POP3, SMTP, and all that.
  311. * Messaging Services:: Messaging services.
  312. * Telephony Services:: Telephony services.
  313. * Monitoring Services:: Monitoring services.
  314. * Kerberos Services:: Kerberos services.
  315. * LDAP Services:: LDAP services.
  316. * Web Services:: Web servers.
  317. * Certificate Services:: TLS certificates via Let's Encrypt.
  318. * DNS Services:: DNS daemons.
  319. * VPN Services:: VPN daemons.
  320. * Network File System:: NFS related services.
  321. * Continuous Integration:: Cuirass and Laminar services.
  322. * Power Management Services:: Extending battery life.
  323. * Audio Services:: The MPD.
  324. * Virtualization Services:: Virtualization services.
  325. * Version Control Services:: Providing remote access to Git repositories.
  326. * Game Services:: Game servers.
  327. * PAM Mount Service:: Service to mount volumes when logging in.
  328. * Guix Services:: Services relating specifically to Guix.
  329. * Linux Services:: Services tied to the Linux kernel.
  330. * Hurd Services:: Services specific for a Hurd System.
  331. * Miscellaneous Services:: Other services.
  332. Defining Services
  333. * Service Composition:: The model for composing services.
  334. * Service Types and Services:: Types and services.
  335. * Service Reference:: API reference.
  336. * Shepherd Services:: A particular type of service.
  337. * Complex Configurations:: Defining bindings for complex configurations.
  338. Installing Debugging Files
  339. * Separate Debug Info:: Installing 'debug' outputs.
  340. * Rebuilding Debug Info:: Building missing debug info.
  341. Bootstrapping
  342. * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
  343. * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
  344. @end detailmenu
  345. @end menu
  346. @c *********************************************************************
  347. @node Introduction
  348. @chapter Introduction
  349. @cindex purpose
  350. GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
  351. using the international phonetic alphabet (IPA).} is a package
  352. management tool for and distribution of the GNU system.
  353. Guix makes it easy for unprivileged
  354. users to install, upgrade, or remove software packages, to roll back to a
  355. previous package set, to build packages from source, and generally
  356. assists with the creation and maintenance of software environments.
  357. @cindex Guix System
  358. @cindex GuixSD, now Guix System
  359. @cindex Guix System Distribution, now Guix System
  360. You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
  361. complements the available tools without interference (@pxref{Installation}),
  362. or you can use it as a standalone operating system distribution,
  363. @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
  364. System Distribution'' or ``GuixSD''. We now consider it makes more sense to
  365. group everything under the ``Guix'' banner since, after all, Guix System is
  366. readily available through the @command{guix system} command, even if you're
  367. using a different distro underneath!}. @xref{GNU Distribution}.
  368. @menu
  369. * Managing Software the Guix Way:: What's special.
  370. * GNU Distribution:: The packages and tools.
  371. @end menu
  372. @node Managing Software the Guix Way
  373. @section Managing Software the Guix Way
  374. @cindex user interfaces
  375. Guix provides a command-line package management interface
  376. (@pxref{Package Management}), tools to help with software development
  377. (@pxref{Development}), command-line utilities for more advanced usage
  378. (@pxref{Utilities}), as well as Scheme programming interfaces
  379. (@pxref{Programming Interface}).
  380. @cindex build daemon
  381. Its @dfn{build daemon} is responsible for building packages on behalf of
  382. users (@pxref{Setting Up the Daemon}) and for downloading pre-built
  383. binaries from authorized sources (@pxref{Substitutes}).
  384. @cindex extensibility of the distribution
  385. @cindex customization, of packages
  386. Guix includes package definitions for many GNU and non-GNU packages, all
  387. of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
  388. user's computing freedom}. It is @emph{extensible}: users can write
  389. their own package definitions (@pxref{Defining Packages}) and make them
  390. available as independent package modules (@pxref{Package Modules}). It
  391. is also @emph{customizable}: users can @emph{derive} specialized package
  392. definitions from existing ones, including from the command line
  393. (@pxref{Package Transformation Options}).
  394. @cindex functional package management
  395. @cindex isolation
  396. Under the hood, Guix implements the @dfn{functional package management}
  397. discipline pioneered by Nix (@pxref{Acknowledgments}).
  398. In Guix, the package build and installation process is seen
  399. as a @emph{function}, in the mathematical sense. That function takes inputs,
  400. such as build scripts, a compiler, and libraries, and
  401. returns an installed package. As a pure function, its result depends
  402. solely on its inputs---for instance, it cannot refer to software or
  403. scripts that were not explicitly passed as inputs. A build function
  404. always produces the same result when passed a given set of inputs. It
  405. cannot alter the environment of the running system in
  406. any way; for instance, it cannot create, modify, or delete files outside
  407. of its build and installation directories. This is achieved by running
  408. build processes in isolated environments (or @dfn{containers}), where only their
  409. explicit inputs are visible.
  410. @cindex store
  411. The result of package build functions is @dfn{cached} in the file
  412. system, in a special directory called @dfn{the store} (@pxref{The
  413. Store}). Each package is installed in a directory of its own in the
  414. store---by default under @file{/gnu/store}. The directory name contains
  415. a hash of all the inputs used to build that package; thus, changing an
  416. input yields a different directory name.
  417. This approach is the foundation for the salient features of Guix: support
  418. for transactional package upgrade and rollback, per-user installation, and
  419. garbage collection of packages (@pxref{Features}).
  420. @node GNU Distribution
  421. @section GNU Distribution
  422. @cindex Guix System
  423. Guix comes with a distribution of the GNU system consisting entirely of
  424. free software@footnote{The term ``free'' here refers to the
  425. @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
  426. users of that software}.}. The
  427. distribution can be installed on its own (@pxref{System Installation}),
  428. but it is also possible to install Guix as a package manager on top of
  429. an installed GNU/Linux system (@pxref{Installation}). When we need to
  430. distinguish between the two, we refer to the standalone distribution as
  431. Guix@tie{}System.
  432. The distribution provides core GNU packages such as GNU libc, GCC, and
  433. Binutils, as well as many GNU and non-GNU applications. The complete
  434. list of available packages can be browsed
  435. @url{https://www.gnu.org/software/guix/packages,on-line} or by
  436. running @command{guix package} (@pxref{Invoking guix package}):
  437. @example
  438. guix package --list-available
  439. @end example
  440. Our goal is to provide a practical 100% free software distribution of
  441. Linux-based and other variants of GNU, with a focus on the promotion and
  442. tight integration of GNU components, and an emphasis on programs and
  443. tools that help users exert that freedom.
  444. Packages are currently available on the following platforms:
  445. @table @code
  446. @item x86_64-linux
  447. Intel/AMD @code{x86_64} architecture, Linux-Libre kernel.
  448. @item i686-linux
  449. Intel 32-bit architecture (IA32), Linux-Libre kernel.
  450. @item armhf-linux
  451. ARMv7-A architecture with hard float, Thumb-2 and NEON,
  452. using the EABI hard-float application binary interface (ABI),
  453. and Linux-Libre kernel.
  454. @item aarch64-linux
  455. little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
  456. @item i586-gnu
  457. @uref{https://hurd.gnu.org, GNU/Hurd} on the Intel 32-bit architecture
  458. (IA32).
  459. This configuration is experimental and under development. The easiest
  460. way for you to give it a try is by setting up an instance of
  461. @code{hurd-vm-service-type} on your GNU/Linux machine
  462. (@pxref{transparent-emulation-qemu, @code{hurd-vm-service-type}}).
  463. @xref{Contributing}, on how to help!
  464. @item mips64el-linux (unsupported)
  465. little-endian 64-bit MIPS processors, specifically the Loongson series,
  466. n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
  467. supported; in particular, there is no ongoing work to ensure that this
  468. architecture still works. Should someone decide they wish to revive this
  469. architecture then the code is still available.
  470. @item powerpc-linux (unsupported)
  471. big-endian 32-bit PowerPC processors, specifically the PowerPC G4 with
  472. AltiVec support, and Linux-Libre kernel. This configuration is not
  473. fully supported and there is no ongoing work to ensure this architecture
  474. works.
  475. @item powerpc64le-linux
  476. little-endian 64-bit Power ISA processors, Linux-Libre kernel. This
  477. includes POWER9 systems such as the
  478. @uref{https://www.fsf.org/news/talos-ii-mainboard-and-talos-ii-lite-mainboard-now-fsf-certified-to-respect-your-freedom,
  479. RYF Talos II mainboard}. This platform is available as a "technology
  480. preview": although it is supported, substitutes are not yet available
  481. from the build farm (@pxref{Substitutes}), and some packages may fail to
  482. build (@pxref{Tracking Bugs and Patches}). That said, the Guix
  483. community is actively working on improving this support, and now is a
  484. great time to try it and get involved!
  485. @item riscv64-linux
  486. little-endian 64-bit RISC-V processors, specifically RV64GC, and
  487. Linux-Libre kernel. This playform is available as a "technology preview":
  488. although it is supported, substitutes are not yet available from the
  489. build farm (@pxref{Substitutes}), and some packages may fail to build
  490. (@pxref{Tracking Bugs and Patches}). That said, the Guix community is
  491. actively working on improving this support, and now is a great time to
  492. try it and get involved!
  493. @end table
  494. With Guix@tie{}System, you @emph{declare} all aspects of the operating system
  495. configuration and Guix takes care of instantiating the configuration in a
  496. transactional, reproducible, and stateless fashion (@pxref{System
  497. Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
  498. initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
  499. Manual}), the well-known GNU utilities and tool chain, as well as the
  500. graphical environment or system services of your choice.
  501. Guix System is available on all the above platforms except
  502. @code{mips64el-linux}, @code{powerpc-linux}, @code{powerpc64le-linux} and
  503. @code{riscv64-linux}.
  504. @noindent
  505. For information on porting to other architectures or kernels,
  506. @pxref{Porting}.
  507. Building this distribution is a cooperative effort, and you are invited
  508. to join! @xref{Contributing}, for information about how you can help.
  509. @c *********************************************************************
  510. @node Installation
  511. @chapter Installation
  512. @cindex installing Guix
  513. @quotation Note
  514. We recommend the use of this
  515. @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
  516. shell installer script} to install Guix on top of a running GNU/Linux system,
  517. thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
  518. with the installation of the package manager, which can be done on top of a
  519. running GNU/Linux system. If, instead, you want to install the complete GNU
  520. operating system, @pxref{System Installation}.} The script automates the
  521. download, installation, and initial configuration of Guix. It should be run
  522. as the root user.
  523. @end quotation
  524. @cindex foreign distro
  525. @cindex directories related to foreign distro
  526. When installed on a foreign distro, GNU@tie{}Guix complements the available
  527. tools without interference. Its data lives exclusively in two directories,
  528. usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
  529. such as @file{/etc}, are left untouched.
  530. Once installed, Guix can be updated by running @command{guix pull}
  531. (@pxref{Invoking guix pull}).
  532. If you prefer to perform the installation steps manually or want to tweak
  533. them, you may find the following subsections useful. They describe the
  534. software requirements of Guix, as well as how to install it manually and get
  535. ready to use it.
  536. @menu
  537. * Binary Installation:: Getting Guix running in no time!
  538. * Requirements:: Software needed to build and run Guix.
  539. * Running the Test Suite:: Testing Guix.
  540. * Setting Up the Daemon:: Preparing the build daemon's environment.
  541. * Invoking guix-daemon:: Running the build daemon.
  542. * Application Setup:: Application-specific setup.
  543. * Upgrading Guix:: Upgrading Guix and its build daemon.
  544. @end menu
  545. @node Binary Installation
  546. @section Binary Installation
  547. @cindex installing Guix from binaries
  548. @cindex installer script
  549. This section describes how to install Guix on an arbitrary system from a
  550. self-contained tarball providing binaries for Guix and for all its
  551. dependencies. This is often quicker than installing from source, which
  552. is described in the next sections. The only requirement is to have
  553. GNU@tie{}tar and Xz.
  554. @c Note duplicated from the ``Installation'' node.
  555. @quotation Note
  556. We recommend the use of this
  557. @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
  558. shell installer script}. The script automates the download, installation, and
  559. initial configuration steps described below. It should be run as the root
  560. user. As root, you can thus run this:
  561. @example
  562. cd /tmp
  563. wget https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh
  564. chmod +x guix-install.sh
  565. ./guix-install.sh
  566. @end example
  567. When you're done, @pxref{Application Setup} for extra configuration you
  568. might need, and @ref{Getting Started} for your first steps!
  569. @end quotation
  570. Installing goes along these lines:
  571. @enumerate
  572. @item
  573. @cindex downloading Guix binary
  574. Download the binary tarball from
  575. @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz},
  576. where @code{x86_64-linux} can be replaced with @code{i686-linux} for an
  577. @code{i686} (32-bits) machine already running the kernel Linux, and so on
  578. (@pxref{GNU Distribution}).
  579. @c The following is somewhat duplicated in ``System Installation''.
  580. Make sure to download the associated @file{.sig} file and to verify the
  581. authenticity of the tarball against it, along these lines:
  582. @example
  583. $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
  584. $ gpg --verify guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
  585. @end example
  586. If that command fails because you do not have the required public key,
  587. then run this command to import it:
  588. @example
  589. $ wget '@value{OPENPGP-SIGNING-KEY-URL}' \
  590. -qO - | gpg --import -
  591. @end example
  592. @noindent
  593. and rerun the @code{gpg --verify} command.
  594. Take note that a warning like ``This key is not certified with a trusted
  595. signature!'' is normal.
  596. @c end authentication part
  597. @item
  598. Now, you need to become the @code{root} user. Depending on your distribution,
  599. you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
  600. @example
  601. # cd /tmp
  602. # tar --warning=no-timestamp -xf \
  603. /path/to/guix-binary-@value{VERSION}.x86_64-linux.tar.xz
  604. # mv var/guix /var/ && mv gnu /
  605. @end example
  606. This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
  607. The latter contains a ready-to-use profile for @code{root} (see next
  608. step).
  609. Do @emph{not} unpack the tarball on a working Guix system since that
  610. would overwrite its own essential files.
  611. The @option{--warning=no-timestamp} option makes sure GNU@tie{}tar does
  612. not emit warnings about ``implausibly old time stamps'' (such
  613. warnings were triggered by GNU@tie{}tar 1.26 and older; recent
  614. versions are fine).
  615. They stem from the fact that all the
  616. files in the archive have their modification time set to 1 (which
  617. means January 1st, 1970). This is done on purpose to make sure the
  618. archive content is independent of its creation time, thus making it
  619. reproducible.
  620. @item
  621. Make the profile available under @file{~root/.config/guix/current}, which is
  622. where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
  623. @example
  624. # mkdir -p ~root/.config/guix
  625. # ln -sf /var/guix/profiles/per-user/root/current-guix \
  626. ~root/.config/guix/current
  627. @end example
  628. Source @file{etc/profile} to augment @env{PATH} and other relevant
  629. environment variables:
  630. @example
  631. # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
  632. source $GUIX_PROFILE/etc/profile
  633. @end example
  634. @item
  635. Create the group and user accounts for build users as explained below
  636. (@pxref{Build Environment Setup}).
  637. @item
  638. Run the daemon, and set it to automatically start on boot.
  639. If your host distro uses the systemd init system, this can be achieved
  640. with these commands:
  641. @c Versions of systemd that supported symlinked service files are not
  642. @c yet widely deployed, so we should suggest that users copy the service
  643. @c files into place.
  644. @c
  645. @c See this thread for more information:
  646. @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
  647. @example
  648. # cp ~root/.config/guix/current/lib/systemd/system/gnu-store.mount \
  649. ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
  650. /etc/systemd/system/
  651. # systemctl enable --now gnu-store.mount guix-daemon
  652. @end example
  653. You may also want to arrange for @command{guix gc} to run periodically:
  654. @example
  655. # cp ~root/.config/guix/current/lib/systemd/system/guix-gc.service \
  656. ~root/.config/guix/current/lib/systemd/system/guix-gc.timer \
  657. /etc/systemd/system/
  658. # systemctl enable --now guix-gc.timer
  659. @end example
  660. You may want to edit @file{guix-gc.service} to adjust the command line
  661. options to fit your needs (@pxref{Invoking guix gc}).
  662. If your host distro uses the Upstart init system:
  663. @example
  664. # initctl reload-configuration
  665. # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
  666. /etc/init/
  667. # start guix-daemon
  668. @end example
  669. Otherwise, you can still start the daemon manually with:
  670. @example
  671. # ~root/.config/guix/current/bin/guix-daemon \
  672. --build-users-group=guixbuild
  673. @end example
  674. @item
  675. Make the @command{guix} command available to other users on the machine,
  676. for instance with:
  677. @example
  678. # mkdir -p /usr/local/bin
  679. # cd /usr/local/bin
  680. # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
  681. @end example
  682. It is also a good idea to make the Info version of this manual available
  683. there:
  684. @example
  685. # mkdir -p /usr/local/share/info
  686. # cd /usr/local/share/info
  687. # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
  688. do ln -s $i ; done
  689. @end example
  690. That way, assuming @file{/usr/local/share/info} is in the search path,
  691. running @command{info guix} will open this manual (@pxref{Other Info
  692. Directories,,, texinfo, GNU Texinfo}, for more details on changing the
  693. Info search path).
  694. @item
  695. @cindex substitutes, authorization thereof
  696. To use substitutes from @code{@value{SUBSTITUTE-SERVER-1}},
  697. @code{@value{SUBSTITUTE-SERVER-2}} or a mirror (@pxref{Substitutes}),
  698. authorize them:
  699. @example
  700. # guix archive --authorize < \
  701. ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER-1}.pub
  702. # guix archive --authorize < \
  703. ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER-2}.pub
  704. @end example
  705. @quotation Note
  706. If you do not enable substitutes, Guix will end up building
  707. @emph{everything} from source on your machine, making each installation
  708. and upgrade very expensive. @xref{On Trusting Binaries}, for a
  709. discussion of reasons why one might want do disable substitutes.
  710. @end quotation
  711. @item
  712. Each user may need to perform a few additional steps to make their Guix
  713. environment ready for use, @pxref{Application Setup}.
  714. @end enumerate
  715. Voilà, the installation is complete!
  716. You can confirm that Guix is working by installing a sample package into
  717. the root profile:
  718. @example
  719. # guix install hello
  720. @end example
  721. The binary installation tarball can be (re)produced and verified simply
  722. by running the following command in the Guix source tree:
  723. @example
  724. make guix-binary.@var{system}.tar.xz
  725. @end example
  726. @noindent
  727. ...@: which, in turn, runs:
  728. @example
  729. guix pack -s @var{system} --localstatedir \
  730. --profile-name=current-guix guix
  731. @end example
  732. @xref{Invoking guix pack}, for more info on this handy tool.
  733. @node Requirements
  734. @section Requirements
  735. This section lists requirements when building Guix from source. The
  736. build procedure for Guix is the same as for other GNU software, and is
  737. not covered here. Please see the files @file{README} and @file{INSTALL}
  738. in the Guix source tree for additional details.
  739. @cindex official website
  740. GNU Guix is available for download from its website at
  741. @url{https://www.gnu.org/software/guix/}.
  742. GNU Guix depends on the following packages:
  743. @itemize
  744. @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x,
  745. version 3.0.3 or later;
  746. @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
  747. 0.1.0 or later;
  748. @item
  749. @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
  750. (@pxref{Guile Preparations, how to install the GnuTLS bindings for
  751. Guile,, gnutls-guile, GnuTLS-Guile});
  752. @item
  753. @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
  754. or later;
  755. @item @uref{https://notabug.org/guile-zlib/guile-zlib, Guile-zlib},
  756. version 0.1.0 or later;
  757. @item @uref{https://notabug.org/guile-lzlib/guile-lzlib, Guile-lzlib};
  758. @item @uref{https://www.nongnu.org/guile-avahi/, Guile-Avahi};
  759. @item
  760. @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, version 0.5.0
  761. or later;
  762. @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON}
  763. 4.3.0 or later;
  764. @item @url{https://www.gnu.org/software/make/, GNU Make}.
  765. @end itemize
  766. The following dependencies are optional:
  767. @itemize
  768. @item
  769. @c Note: We need at least 0.13.0 for #:nodelay.
  770. Support for build offloading (@pxref{Daemon Offload Setup}) and
  771. @command{guix copy} (@pxref{Invoking guix copy}) depends on
  772. @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
  773. version 0.13.0 or later.
  774. @item
  775. @uref{https://notabug.org/guile-zstd/guile-zstd, Guile-zstd}, for zstd
  776. compression and decompression in @command{guix publish} and for
  777. substitutes (@pxref{Invoking guix publish}).
  778. @item
  779. @uref{https://ngyro.com/software/guile-semver.html, Guile-Semver} for
  780. the @code{crate} importer (@pxref{Invoking guix import}).
  781. @item
  782. @uref{https://www.nongnu.org/guile-lib/doc/ref/htmlprag/, Guile-Lib} for
  783. the @code{go} importer (@pxref{Invoking guix import}) and for some of
  784. the ``updaters'' (@pxref{Invoking guix refresh}).
  785. @item
  786. When @url{http://www.bzip.org, libbz2} is available,
  787. @command{guix-daemon} can use it to compress build logs.
  788. @end itemize
  789. Unless @option{--disable-daemon} was passed to @command{configure}, the
  790. following packages are also needed:
  791. @itemize
  792. @item @url{https://gnupg.org/, GNU libgcrypt};
  793. @item @url{https://sqlite.org, SQLite 3};
  794. @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
  795. C++11 standard.
  796. @end itemize
  797. @cindex state directory
  798. When configuring Guix on a system that already has a Guix installation,
  799. be sure to specify the same state directory as the existing installation
  800. using the @option{--localstatedir} option of the @command{configure}
  801. script (@pxref{Directory Variables, @code{localstatedir},, standards,
  802. GNU Coding Standards}). Usually, this @var{localstatedir} option is
  803. set to the value @file{/var}. The @command{configure} script protects
  804. against unintended misconfiguration of @var{localstatedir} so you do not
  805. inadvertently corrupt your store (@pxref{The Store}).
  806. @node Running the Test Suite
  807. @section Running the Test Suite
  808. @cindex test suite
  809. After a successful @command{configure} and @code{make} run, it is a good
  810. idea to run the test suite. It can help catch issues with the setup or
  811. environment, or bugs in Guix itself---and really, reporting test
  812. failures is a good way to help improve the software. To run the test
  813. suite, type:
  814. @example
  815. make check
  816. @end example
  817. Test cases can run in parallel: you can use the @code{-j} option of
  818. GNU@tie{}make to speed things up. The first run may take a few minutes
  819. on a recent machine; subsequent runs will be faster because the store
  820. that is created for test purposes will already have various things in
  821. cache.
  822. It is also possible to run a subset of the tests by defining the
  823. @code{TESTS} makefile variable as in this example:
  824. @example
  825. make check TESTS="tests/store.scm tests/cpio.scm"
  826. @end example
  827. By default, tests results are displayed at a file level. In order to
  828. see the details of every individual test cases, it is possible to define
  829. the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
  830. @example
  831. make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
  832. @end example
  833. The underlying SRFI 64 custom Automake test driver used for the 'check'
  834. test suite (located at @file{build-aux/test-driver.scm}) also allows
  835. selecting which test cases to run at a finer level, via its
  836. @option{--select} and @option{--exclude} options. Here's an example, to
  837. run all the test cases from the @file{tests/packages.scm} test file
  838. whose names start with ``transaction-upgrade-entry'':
  839. @example
  840. export SCM_LOG_DRIVER_FLAGS="--select=^transaction-upgrade-entry"
  841. make check TESTS="tests/packages.scm"
  842. @end example
  843. Those wishing to inspect the results of failed tests directly from the
  844. command line can add the @option{--errors-only=yes} option to the
  845. @code{SCM_LOG_DRIVER_FLAGS} makefile variable and set the @code{VERBOSE}
  846. Automake makefile variable, as in:
  847. @example
  848. make check SCM_LOG_DRIVER_FLAGS="--brief=no --errors-only=yes" VERBOSE=1
  849. @end example
  850. The @option{--show-duration=yes} option can be used to print the
  851. duration of the individual test cases, when used in combination with
  852. @option{--brief=no}:
  853. @example
  854. make check SCM_LOG_DRIVER_FLAGS="--brief=no --show-duration=yes"
  855. @end example
  856. @xref{Parallel Test Harness,,,automake,GNU Automake} for more
  857. information about the Automake Parallel Test Harness.
  858. Upon failure, please email @email{bug-guix@@gnu.org} and attach the
  859. @file{test-suite.log} file. Please specify the Guix version being used
  860. as well as version numbers of the dependencies (@pxref{Requirements}) in
  861. your message.
  862. Guix also comes with a whole-system test suite that tests complete
  863. Guix System instances. It can only run on systems where
  864. Guix is already installed, using:
  865. @example
  866. make check-system
  867. @end example
  868. @noindent
  869. or, again, by defining @code{TESTS} to select a subset of tests to run:
  870. @example
  871. make check-system TESTS="basic mcron"
  872. @end example
  873. These system tests are defined in the @code{(gnu tests @dots{})}
  874. modules. They work by running the operating systems under test with
  875. lightweight instrumentation in a virtual machine (VM). They can be
  876. computationally intensive or rather cheap, depending on whether
  877. substitutes are available for their dependencies (@pxref{Substitutes}).
  878. Some of them require a lot of storage space to hold VM images.
  879. Again in case of test failures, please send @email{bug-guix@@gnu.org}
  880. all the details.
  881. @node Setting Up the Daemon
  882. @section Setting Up the Daemon
  883. @cindex daemon
  884. Operations such as building a package or running the garbage collector
  885. are all performed by a specialized process, the @dfn{build daemon}, on
  886. behalf of clients. Only the daemon may access the store and its
  887. associated database. Thus, any operation that manipulates the store
  888. goes through the daemon. For instance, command-line tools such as
  889. @command{guix package} and @command{guix build} communicate with the
  890. daemon (@i{via} remote procedure calls) to instruct it what to do.
  891. The following sections explain how to prepare the build daemon's
  892. environment. See also @ref{Substitutes}, for information on how to allow
  893. the daemon to download pre-built binaries.
  894. @menu
  895. * Build Environment Setup:: Preparing the isolated build environment.
  896. * Daemon Offload Setup:: Offloading builds to remote machines.
  897. * SELinux Support:: Using an SELinux policy for the daemon.
  898. @end menu
  899. @node Build Environment Setup
  900. @subsection Build Environment Setup
  901. @cindex build environment
  902. In a standard multi-user setup, Guix and its daemon---the
  903. @command{guix-daemon} program---are installed by the system
  904. administrator; @file{/gnu/store} is owned by @code{root} and
  905. @command{guix-daemon} runs as @code{root}. Unprivileged users may use
  906. Guix tools to build packages or otherwise access the store, and the
  907. daemon will do it on their behalf, ensuring that the store is kept in a
  908. consistent state, and allowing built packages to be shared among users.
  909. @cindex build users
  910. When @command{guix-daemon} runs as @code{root}, you may not want package
  911. build processes themselves to run as @code{root} too, for obvious
  912. security reasons. To avoid that, a special pool of @dfn{build users}
  913. should be created for use by build processes started by the daemon.
  914. These build users need not have a shell and a home directory: they will
  915. just be used when the daemon drops @code{root} privileges in build
  916. processes. Having several such users allows the daemon to launch
  917. distinct build processes under separate UIDs, which guarantees that they
  918. do not interfere with each other---an essential feature since builds are
  919. regarded as pure functions (@pxref{Introduction}).
  920. On a GNU/Linux system, a build user pool may be created like this (using
  921. Bash syntax and the @code{shadow} commands):
  922. @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
  923. @c for why `-G' is needed.
  924. @example
  925. # groupadd --system guixbuild
  926. # for i in $(seq -w 1 10);
  927. do
  928. useradd -g guixbuild -G guixbuild \
  929. -d /var/empty -s $(which nologin) \
  930. -c "Guix build user $i" --system \
  931. guixbuilder$i;
  932. done
  933. @end example
  934. @noindent
  935. The number of build users determines how many build jobs may run in
  936. parallel, as specified by the @option{--max-jobs} option
  937. (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
  938. @command{guix system vm} and related commands, you may need to add the
  939. build users to the @code{kvm} group so they can access @file{/dev/kvm},
  940. using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
  941. (@pxref{Invoking guix system}).
  942. The @code{guix-daemon} program may then be run as @code{root} with the
  943. following command@footnote{If your machine uses the systemd init system,
  944. dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
  945. file in @file{/etc/systemd/system} will ensure that
  946. @command{guix-daemon} is automatically started. Similarly, if your
  947. machine uses the Upstart init system, drop the
  948. @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
  949. file in @file{/etc/init}.}:
  950. @example
  951. # guix-daemon --build-users-group=guixbuild
  952. @end example
  953. @cindex chroot
  954. @noindent
  955. This way, the daemon starts build processes in a chroot, under one of
  956. the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
  957. environment contains nothing but:
  958. @c Keep this list in sync with libstore/build.cc! -----------------------
  959. @itemize
  960. @item
  961. a minimal @code{/dev} directory, created mostly independently from the
  962. host @code{/dev}@footnote{``Mostly'', because while the set of files
  963. that appear in the chroot's @code{/dev} is fixed, most of these files
  964. can only be created if the host has them.};
  965. @item
  966. the @code{/proc} directory; it only shows the processes of the container
  967. since a separate PID name space is used;
  968. @item
  969. @file{/etc/passwd} with an entry for the current user and an entry for
  970. user @file{nobody};
  971. @item
  972. @file{/etc/group} with an entry for the user's group;
  973. @item
  974. @file{/etc/hosts} with an entry that maps @code{localhost} to
  975. @code{127.0.0.1};
  976. @item
  977. a writable @file{/tmp} directory.
  978. @end itemize
  979. The chroot does not contain a @file{/home} directory, and the @env{HOME}
  980. environment variable is set to the non-existent
  981. @file{/homeless-shelter}. This helps to highlight inappropriate uses of
  982. @env{HOME} in the build scripts of packages.
  983. You can influence the directory where the daemon stores build trees
  984. @i{via} the @env{TMPDIR} environment variable. However, the build tree
  985. within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
  986. where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
  987. This way, the value of @env{TMPDIR} does not leak inside build
  988. environments, which avoids discrepancies in cases where build processes
  989. capture the name of their build tree.
  990. @vindex http_proxy
  991. @vindex https_proxy
  992. The daemon also honors the @env{http_proxy} and @env{https_proxy}
  993. environment variables for HTTP and HTTPS downloads it performs, be it
  994. for fixed-output derivations (@pxref{Derivations}) or for substitutes
  995. (@pxref{Substitutes}).
  996. If you are installing Guix as an unprivileged user, it is still possible
  997. to run @command{guix-daemon} provided you pass @option{--disable-chroot}.
  998. However, build processes will not be isolated from one another, and not
  999. from the rest of the system. Thus, build processes may interfere with
  1000. each other, and may access programs, libraries, and other files
  1001. available on the system---making it much harder to view them as
  1002. @emph{pure} functions.
  1003. @node Daemon Offload Setup
  1004. @subsection Using the Offload Facility
  1005. @cindex offloading
  1006. @cindex build hook
  1007. When desired, the build daemon can @dfn{offload} derivation builds to
  1008. other machines running Guix, using the @code{offload} @dfn{build
  1009. hook}@footnote{This feature is available only when
  1010. @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
  1011. present.}. When that feature is enabled, a list of user-specified build
  1012. machines is read from @file{/etc/guix/machines.scm}; every time a build
  1013. is requested, for instance via @code{guix build}, the daemon attempts to
  1014. offload it to one of the machines that satisfy the constraints of the
  1015. derivation, in particular its system types---e.g., @code{x86_64-linux}.
  1016. A single machine can have multiple system types, either because its
  1017. architecture natively supports it, via emulation
  1018. (@pxref{transparent-emulation-qemu, Transparent Emulation with QEMU}),
  1019. or both. Missing prerequisites for the build are
  1020. copied over SSH to the target machine, which then proceeds with the
  1021. build; upon success the output(s) of the build are copied back to the
  1022. initial machine. The offload facility comes with a basic scheduler that
  1023. attempts to select the best machine. The best machine is chosen among
  1024. the available machines based on criteria such as:
  1025. @enumerate
  1026. @item
  1027. The availability of a build slot. A build machine can have as many
  1028. build slots (connections) as the value of the @code{parallel-builds}
  1029. field of its @code{build-machine} object.
  1030. @item
  1031. Its relative speed, as defined via the @code{speed} field of its
  1032. @code{build-machine} object.
  1033. @item
  1034. Its load. The normalized machine load must be lower than a threshold
  1035. value, configurable via the @code{overload-threshold} field of its
  1036. @code{build-machine} object.
  1037. @item
  1038. Disk space availability. More than a 100 MiB must be available.
  1039. @end enumerate
  1040. The @file{/etc/guix/machines.scm} file typically looks like this:
  1041. @lisp
  1042. (list (build-machine
  1043. (name "eightysix.example.org")
  1044. (systems (list "x86_64-linux" "i686-linux"))
  1045. (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
  1046. (user "bob")
  1047. (speed 2.)) ;incredibly fast!
  1048. (build-machine
  1049. (name "armeight.example.org")
  1050. (systems (list "aarch64-linux"))
  1051. (host-key "ssh-rsa AAAAB3Nza@dots{}")
  1052. (user "alice")
  1053. ;; Remember 'guix offload' is spawned by
  1054. ;; 'guix-daemon' as root.
  1055. (private-key "/root/.ssh/identity-for-guix")))
  1056. @end lisp
  1057. @noindent
  1058. In the example above we specify a list of two build machines, one for
  1059. the @code{x86_64} and @code{i686} architectures and one for the
  1060. @code{aarch64} architecture.
  1061. In fact, this file is---not surprisingly!---a Scheme file that is
  1062. evaluated when the @code{offload} hook is started. Its return value
  1063. must be a list of @code{build-machine} objects. While this example
  1064. shows a fixed list of build machines, one could imagine, say, using
  1065. DNS-SD to return a list of potential build machines discovered in the
  1066. local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
  1067. Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
  1068. detailed below.
  1069. @deftp {Data Type} build-machine
  1070. This data type represents build machines to which the daemon may offload
  1071. builds. The important fields are:
  1072. @table @code
  1073. @item name
  1074. The host name of the remote machine.
  1075. @item systems
  1076. The system types the remote machine supports---e.g., @code{(list
  1077. "x86_64-linux" "i686-linux")}.
  1078. @item user
  1079. The user account to use when connecting to the remote machine over SSH.
  1080. Note that the SSH key pair must @emph{not} be passphrase-protected, to
  1081. allow non-interactive logins.
  1082. @item host-key
  1083. This must be the machine's SSH @dfn{public host key} in OpenSSH format.
  1084. This is used to authenticate the machine when we connect to it. It is a
  1085. long string that looks like this:
  1086. @example
  1087. ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
  1088. @end example
  1089. If the machine is running the OpenSSH daemon, @command{sshd}, the host
  1090. key can be found in a file such as
  1091. @file{/etc/ssh/ssh_host_ed25519_key.pub}.
  1092. If the machine is running the SSH daemon of GNU@tie{}lsh,
  1093. @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
  1094. similar file. It can be converted to the OpenSSH format using
  1095. @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
  1096. @example
  1097. $ lsh-export-key --openssh < /etc/lsh/host-key.pub
  1098. ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
  1099. @end example
  1100. @end table
  1101. A number of optional fields may be specified:
  1102. @table @asis
  1103. @item @code{port} (default: @code{22})
  1104. Port number of SSH server on the machine.
  1105. @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
  1106. The SSH private key file to use when connecting to the machine, in
  1107. OpenSSH format. This key must not be protected with a passphrase.
  1108. Note that the default value is the private key @emph{of the root
  1109. account}. Make sure it exists if you use the default.
  1110. @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
  1111. @itemx @code{compression-level} (default: @code{3})
  1112. The SSH-level compression methods and compression level requested.
  1113. Note that offloading relies on SSH compression to reduce bandwidth usage
  1114. when transferring files to and from build machines.
  1115. @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
  1116. File name of the Unix-domain socket @command{guix-daemon} is listening
  1117. to on that machine.
  1118. @item @code{overload-threshold} (default: @code{0.6})
  1119. The load threshold above which a potential offload machine is
  1120. disregarded by the offload scheduler. The value roughly translates to
  1121. the total processor usage of the build machine, ranging from 0.0 (0%) to
  1122. 1.0 (100%). It can also be disabled by setting
  1123. @code{overload-threshold} to @code{#f}.
  1124. @item @code{parallel-builds} (default: @code{1})
  1125. The number of builds that may run in parallel on the machine.
  1126. @item @code{speed} (default: @code{1.0})
  1127. A ``relative speed factor''. The offload scheduler will tend to prefer
  1128. machines with a higher speed factor.
  1129. @item @code{features} (default: @code{'()})
  1130. A list of strings denoting specific features supported by the machine.
  1131. An example is @code{"kvm"} for machines that have the KVM Linux modules
  1132. and corresponding hardware support. Derivations can request features by
  1133. name, and they will be scheduled on matching build machines.
  1134. @end table
  1135. @end deftp
  1136. The @command{guix} command must be in the search path on the build
  1137. machines. You can check whether this is the case by running:
  1138. @example
  1139. ssh build-machine guix repl --version
  1140. @end example
  1141. There is one last thing to do once @file{machines.scm} is in place. As
  1142. explained above, when offloading, files are transferred back and forth
  1143. between the machine stores. For this to work, you first need to
  1144. generate a key pair on each machine to allow the daemon to export signed
  1145. archives of files from the store (@pxref{Invoking guix archive}):
  1146. @example
  1147. # guix archive --generate-key
  1148. @end example
  1149. @noindent
  1150. Each build machine must authorize the key of the master machine so that
  1151. it accepts store items it receives from the master:
  1152. @example
  1153. # guix archive --authorize < master-public-key.txt
  1154. @end example
  1155. @noindent
  1156. Likewise, the master machine must authorize the key of each build machine.
  1157. All the fuss with keys is here to express pairwise mutual trust
  1158. relations between the master and the build machines. Concretely, when
  1159. the master receives files from a build machine (and @i{vice versa}), its
  1160. build daemon can make sure they are genuine, have not been tampered
  1161. with, and that they are signed by an authorized key.
  1162. @cindex offload test
  1163. To test whether your setup is operational, run this command on the
  1164. master node:
  1165. @example
  1166. # guix offload test
  1167. @end example
  1168. This will attempt to connect to each of the build machines specified in
  1169. @file{/etc/guix/machines.scm}, make sure Guix is
  1170. available on each machine, attempt to export to the machine and import
  1171. from it, and report any error in the process.
  1172. If you want to test a different machine file, just specify it on the
  1173. command line:
  1174. @example
  1175. # guix offload test machines-qualif.scm
  1176. @end example
  1177. Last, you can test the subset of the machines whose name matches a
  1178. regular expression like this:
  1179. @example
  1180. # guix offload test machines.scm '\.gnu\.org$'
  1181. @end example
  1182. @cindex offload status
  1183. To display the current load of all build hosts, run this command on the
  1184. main node:
  1185. @example
  1186. # guix offload status
  1187. @end example
  1188. @node SELinux Support
  1189. @subsection SELinux Support
  1190. @cindex SELinux, daemon policy
  1191. @cindex mandatory access control, SELinux
  1192. @cindex security, guix-daemon
  1193. Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
  1194. can be installed on a system where SELinux is enabled, in order to label
  1195. Guix files and to specify the expected behavior of the daemon. Since
  1196. Guix System does not provide an SELinux base policy, the daemon policy cannot
  1197. be used on Guix System.
  1198. @subsubsection Installing the SELinux policy
  1199. @cindex SELinux, policy installation
  1200. To install the policy run this command as root:
  1201. @example
  1202. semodule -i etc/guix-daemon.cil
  1203. @end example
  1204. Then relabel the file system with @code{restorecon} or by a different
  1205. mechanism provided by your system.
  1206. Once the policy is installed, the file system has been relabeled, and
  1207. the daemon has been restarted, it should be running in the
  1208. @code{guix_daemon_t} context. You can confirm this with the following
  1209. command:
  1210. @example
  1211. ps -Zax | grep guix-daemon
  1212. @end example
  1213. Monitor the SELinux log files as you run a command like @code{guix build
  1214. hello} to convince yourself that SELinux permits all necessary
  1215. operations.
  1216. @subsubsection Limitations
  1217. @cindex SELinux, limitations
  1218. This policy is not perfect. Here is a list of limitations or quirks
  1219. that should be considered when deploying the provided SELinux policy for
  1220. the Guix daemon.
  1221. @enumerate
  1222. @item
  1223. @code{guix_daemon_socket_t} isn’t actually used. None of the socket
  1224. operations involve contexts that have anything to do with
  1225. @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
  1226. but it would be preferable to define socket rules for only this label.
  1227. @item
  1228. @code{guix gc} cannot access arbitrary links to profiles. By design,
  1229. the file label of the destination of a symlink is independent of the
  1230. file label of the link itself. Although all profiles under
  1231. $localstatedir are labelled, the links to these profiles inherit the
  1232. label of the directory they are in. For links in the user’s home
  1233. directory this will be @code{user_home_t}. But for links from the root
  1234. user’s home directory, or @file{/tmp}, or the HTTP server’s working
  1235. directory, etc, this won’t work. @code{guix gc} would be prevented from
  1236. reading and following these links.
  1237. @item
  1238. The daemon’s feature to listen for TCP connections might no longer work.
  1239. This might require extra rules, because SELinux treats network sockets
  1240. differently from files.
  1241. @item
  1242. Currently all files with a name matching the regular expression
  1243. @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
  1244. label @code{guix_daemon_exec_t}; this means that @emph{any} file with
  1245. that name in any profile would be permitted to run in the
  1246. @code{guix_daemon_t} domain. This is not ideal. An attacker could
  1247. build a package that provides this executable and convince a user to
  1248. install and run it, which lifts it into the @code{guix_daemon_t} domain.
  1249. At that point SELinux could not prevent it from accessing files that are
  1250. allowed for processes in that domain.
  1251. You will need to relabel the store directory after all upgrades to
  1252. @file{guix-daemon}, such as after running @code{guix pull}. Assuming the
  1253. store is in @file{/gnu}, you can do this with @code{restorecon -vR /gnu},
  1254. or by other means provided by your operating system.
  1255. We could generate a much more restrictive policy at installation time,
  1256. so that only the @emph{exact} file name of the currently installed
  1257. @code{guix-daemon} executable would be labelled with
  1258. @code{guix_daemon_exec_t}, instead of using a broad regular expression.
  1259. The downside is that root would have to install or upgrade the policy at
  1260. installation time whenever the Guix package that provides the
  1261. effectively running @code{guix-daemon} executable is upgraded.
  1262. @end enumerate
  1263. @node Invoking guix-daemon
  1264. @section Invoking @command{guix-daemon}
  1265. The @command{guix-daemon} program implements all the functionality to
  1266. access the store. This includes launching build processes, running the
  1267. garbage collector, querying the availability of a build result, etc. It
  1268. is normally run as @code{root} like this:
  1269. @example
  1270. # guix-daemon --build-users-group=guixbuild
  1271. @end example
  1272. @noindent
  1273. For details on how to set it up, @pxref{Setting Up the Daemon}.
  1274. @cindex chroot
  1275. @cindex container, build environment
  1276. @cindex build environment
  1277. @cindex reproducible builds
  1278. By default, @command{guix-daemon} launches build processes under
  1279. different UIDs, taken from the build group specified with
  1280. @option{--build-users-group}. In addition, each build process is run in a
  1281. chroot environment that only contains the subset of the store that the
  1282. build process depends on, as specified by its derivation
  1283. (@pxref{Programming Interface, derivation}), plus a set of specific
  1284. system directories. By default, the latter contains @file{/dev} and
  1285. @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
  1286. @dfn{container}: in addition to having its own file system tree, it has
  1287. a separate mount name space, its own PID name space, network name space,
  1288. etc. This helps achieve reproducible builds (@pxref{Features}).
  1289. When the daemon performs a build on behalf of the user, it creates a
  1290. build directory under @file{/tmp} or under the directory specified by
  1291. its @env{TMPDIR} environment variable. This directory is shared with
  1292. the container for the duration of the build, though within the container,
  1293. the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
  1294. The build directory is automatically deleted upon completion, unless the
  1295. build failed and the client specified @option{--keep-failed}
  1296. (@pxref{Common Build Options, @option{--keep-failed}}).
  1297. The daemon listens for connections and spawns one sub-process for each session
  1298. started by a client (one of the @command{guix} sub-commands). The
  1299. @command{guix processes} command allows you to get an overview of the activity
  1300. on your system by viewing each of the active sessions and clients.
  1301. @xref{Invoking guix processes}, for more information.
  1302. The following command-line options are supported:
  1303. @table @code
  1304. @item --build-users-group=@var{group}
  1305. Take users from @var{group} to run build processes (@pxref{Setting Up
  1306. the Daemon, build users}).
  1307. @item --no-substitutes
  1308. @cindex substitutes
  1309. Do not use substitutes for build products. That is, always build things
  1310. locally instead of allowing downloads of pre-built binaries
  1311. (@pxref{Substitutes}).
  1312. When the daemon runs with @option{--no-substitutes}, clients can still
  1313. explicitly enable substitution @i{via} the @code{set-build-options}
  1314. remote procedure call (@pxref{The Store}).
  1315. @anchor{daemon-substitute-urls}
  1316. @item --substitute-urls=@var{urls}
  1317. Consider @var{urls} the default whitespace-separated list of substitute
  1318. source URLs. When this option is omitted,
  1319. @indicateurl{@value{SUBSTITUTE-URLS}} is used.
  1320. This means that substitutes may be downloaded from @var{urls}, as long
  1321. as they are signed by a trusted signature (@pxref{Substitutes}).
  1322. @xref{Getting Substitutes from Other Servers}, for more information on
  1323. how to configure the daemon to get substitutes from other servers.
  1324. @cindex offloading
  1325. @item --no-offload
  1326. Do not use offload builds to other machines (@pxref{Daemon Offload
  1327. Setup}). That is, always build things locally instead of offloading
  1328. builds to remote machines.
  1329. @item --cache-failures
  1330. Cache build failures. By default, only successful builds are cached.
  1331. When this option is used, @command{guix gc --list-failures} can be used
  1332. to query the set of store items marked as failed; @command{guix gc
  1333. --clear-failures} removes store items from the set of cached failures.
  1334. @xref{Invoking guix gc}.
  1335. @item --cores=@var{n}
  1336. @itemx -c @var{n}
  1337. Use @var{n} CPU cores to build each derivation; @code{0} means as many
  1338. as available.
  1339. The default value is @code{0}, but it may be overridden by clients, such
  1340. as the @option{--cores} option of @command{guix build} (@pxref{Invoking
  1341. guix build}).
  1342. The effect is to define the @env{NIX_BUILD_CORES} environment variable
  1343. in the build process, which can then use it to exploit internal
  1344. parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
  1345. @item --max-jobs=@var{n}
  1346. @itemx -M @var{n}
  1347. Allow at most @var{n} build jobs in parallel. The default value is
  1348. @code{1}. Setting it to @code{0} means that no builds will be performed
  1349. locally; instead, the daemon will offload builds (@pxref{Daemon Offload
  1350. Setup}), or simply fail.
  1351. @item --max-silent-time=@var{seconds}
  1352. When the build or substitution process remains silent for more than
  1353. @var{seconds}, terminate it and report a build failure.
  1354. The default value is @code{0}, which disables the timeout.
  1355. The value specified here can be overridden by clients (@pxref{Common
  1356. Build Options, @option{--max-silent-time}}).
  1357. @item --timeout=@var{seconds}
  1358. Likewise, when the build or substitution process lasts for more than
  1359. @var{seconds}, terminate it and report a build failure.
  1360. The default value is @code{0}, which disables the timeout.
  1361. The value specified here can be overridden by clients (@pxref{Common
  1362. Build Options, @option{--timeout}}).
  1363. @item --rounds=@var{N}
  1364. Build each derivation @var{n} times in a row, and raise an error if
  1365. consecutive build results are not bit-for-bit identical. Note that this
  1366. setting can be overridden by clients such as @command{guix build}
  1367. (@pxref{Invoking guix build}).
  1368. When used in conjunction with @option{--keep-failed}, the differing
  1369. output is kept in the store, under @file{/gnu/store/@dots{}-check}.
  1370. This makes it easy to look for differences between the two results.
  1371. @item --debug
  1372. Produce debugging output.
  1373. This is useful to debug daemon start-up issues, but then it may be
  1374. overridden by clients, for example the @option{--verbosity} option of
  1375. @command{guix build} (@pxref{Invoking guix build}).
  1376. @item --chroot-directory=@var{dir}
  1377. Add @var{dir} to the build chroot.
  1378. Doing this may change the result of build processes---for instance if
  1379. they use optional dependencies found in @var{dir} when it is available,
  1380. and not otherwise. For that reason, it is not recommended to do so.
  1381. Instead, make sure that each derivation declares all the inputs that it
  1382. needs.
  1383. @item --disable-chroot
  1384. Disable chroot builds.
  1385. Using this option is not recommended since, again, it would allow build
  1386. processes to gain access to undeclared dependencies. It is necessary,
  1387. though, when @command{guix-daemon} is running under an unprivileged user
  1388. account.
  1389. @item --log-compression=@var{type}
  1390. Compress build logs according to @var{type}, one of @code{gzip},
  1391. @code{bzip2}, or @code{none}.
  1392. Unless @option{--lose-logs} is used, all the build logs are kept in the
  1393. @var{localstatedir}. To save space, the daemon automatically compresses
  1394. them with gzip by default.
  1395. @item --discover[=yes|no]
  1396. Whether to discover substitute servers on the local network using mDNS
  1397. and DNS-SD.
  1398. This feature is still experimental. However, here are a few
  1399. considerations.
  1400. @enumerate
  1401. @item
  1402. It might be faster/less expensive than fetching from remote servers;
  1403. @item
  1404. There are no security risks, only genuine substitutes will be used
  1405. (@pxref{Substitute Authentication});
  1406. @item
  1407. An attacker advertising @command{guix publish} on your LAN cannot serve
  1408. you malicious binaries, but they can learn what software you’re
  1409. installing;
  1410. @item
  1411. Servers may serve substitute over HTTP, unencrypted, so anyone on the
  1412. LAN can see what software you’re installing.
  1413. @end enumerate
  1414. It is also possible to enable or disable substitute server discovery at
  1415. run-time by running:
  1416. @example
  1417. herd discover guix-daemon on
  1418. herd discover guix-daemon off
  1419. @end example
  1420. @item --disable-deduplication
  1421. @cindex deduplication
  1422. Disable automatic file ``deduplication'' in the store.
  1423. By default, files added to the store are automatically ``deduplicated'':
  1424. if a newly added file is identical to another one found in the store,
  1425. the daemon makes the new file a hard link to the other file. This can
  1426. noticeably reduce disk usage, at the expense of slightly increased
  1427. input/output load at the end of a build process. This option disables
  1428. this optimization.
  1429. @item --gc-keep-outputs[=yes|no]
  1430. Tell whether the garbage collector (GC) must keep outputs of live
  1431. derivations.
  1432. @cindex GC roots
  1433. @cindex garbage collector roots
  1434. When set to @code{yes}, the GC will keep the outputs of any live
  1435. derivation available in the store---the @file{.drv} files. The default
  1436. is @code{no}, meaning that derivation outputs are kept only if they are
  1437. reachable from a GC root. @xref{Invoking guix gc}, for more on GC
  1438. roots.
  1439. @item --gc-keep-derivations[=yes|no]
  1440. Tell whether the garbage collector (GC) must keep derivations
  1441. corresponding to live outputs.
  1442. When set to @code{yes}, as is the case by default, the GC keeps
  1443. derivations---i.e., @file{.drv} files---as long as at least one of their
  1444. outputs is live. This allows users to keep track of the origins of
  1445. items in their store. Setting it to @code{no} saves a bit of disk
  1446. space.
  1447. In this way, setting @option{--gc-keep-derivations} to @code{yes} causes
  1448. liveness to flow from outputs to derivations, and setting
  1449. @option{--gc-keep-outputs} to @code{yes} causes liveness to flow from
  1450. derivations to outputs. When both are set to @code{yes}, the effect is
  1451. to keep all the build prerequisites (the sources, compiler, libraries,
  1452. and other build-time tools) of live objects in the store, regardless of
  1453. whether these prerequisites are reachable from a GC root. This is
  1454. convenient for developers since it saves rebuilds or downloads.
  1455. @item --impersonate-linux-2.6
  1456. On Linux-based systems, impersonate Linux 2.6. This means that the
  1457. kernel's @command{uname} system call will report 2.6 as the release number.
  1458. This might be helpful to build programs that (usually wrongfully) depend
  1459. on the kernel version number.
  1460. @item --lose-logs
  1461. Do not keep build logs. By default they are kept under
  1462. @file{@var{localstatedir}/guix/log}.
  1463. @item --system=@var{system}
  1464. Assume @var{system} as the current system type. By default it is the
  1465. architecture/kernel pair found at configure time, such as
  1466. @code{x86_64-linux}.
  1467. @item --listen=@var{endpoint}
  1468. Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
  1469. as the file name of a Unix-domain socket if it starts with
  1470. @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
  1471. host name or host name and port to listen to. Here are a few examples:
  1472. @table @code
  1473. @item --listen=/gnu/var/daemon
  1474. Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
  1475. creating it if needed.
  1476. @item --listen=localhost
  1477. @cindex daemon, remote access
  1478. @cindex remote access to the daemon
  1479. @cindex daemon, cluster setup
  1480. @cindex clusters, daemon setup
  1481. Listen for TCP connections on the network interface corresponding to
  1482. @code{localhost}, on port 44146.
  1483. @item --listen=128.0.0.42:1234
  1484. Listen for TCP connections on the network interface corresponding to
  1485. @code{128.0.0.42}, on port 1234.
  1486. @end table
  1487. This option can be repeated multiple times, in which case
  1488. @command{guix-daemon} accepts connections on all the specified
  1489. endpoints. Users can tell client commands what endpoint to connect to
  1490. by setting the @env{GUIX_DAEMON_SOCKET} environment variable
  1491. (@pxref{The Store, @env{GUIX_DAEMON_SOCKET}}).
  1492. @quotation Note
  1493. The daemon protocol is @emph{unauthenticated and unencrypted}. Using
  1494. @option{--listen=@var{host}} is suitable on local networks, such as
  1495. clusters, where only trusted nodes may connect to the build daemon. In
  1496. other cases where remote access to the daemon is needed, we recommend
  1497. using Unix-domain sockets along with SSH.
  1498. @end quotation
  1499. When @option{--listen} is omitted, @command{guix-daemon} listens for
  1500. connections on the Unix-domain socket located at
  1501. @file{@var{localstatedir}/guix/daemon-socket/socket}.
  1502. @end table
  1503. @node Application Setup
  1504. @section Application Setup
  1505. @cindex foreign distro
  1506. When using Guix on top of GNU/Linux distribution other than Guix System---a
  1507. so-called @dfn{foreign distro}---a few additional steps are needed to
  1508. get everything in place. Here are some of them.
  1509. @subsection Locales
  1510. @anchor{locales-and-locpath}
  1511. @cindex locales, when not on Guix System
  1512. @vindex LOCPATH
  1513. @vindex GUIX_LOCPATH
  1514. Packages installed @i{via} Guix will not use the locale data of the
  1515. host system. Instead, you must first install one of the locale packages
  1516. available with Guix and then define the @env{GUIX_LOCPATH} environment
  1517. variable:
  1518. @example
  1519. $ guix install glibc-locales
  1520. $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
  1521. @end example
  1522. Note that the @code{glibc-locales} package contains data for all the
  1523. locales supported by the GNU@tie{}libc and weighs in at around
  1524. 930@tie{}MiB@footnote{The size of the @code{glibc-locales} package is
  1525. reduced down to about 213@tie{}MiB with store deduplication and further
  1526. down to about 67@tie{}MiB when using a zstd-compressed Btrfs file
  1527. system.}. If you only need a few locales, you can define your custom
  1528. locales package via the @code{make-glibc-utf8-locales} procedure from
  1529. the @code{(gnu packages base)} module. The following example defines a
  1530. package containing the various Canadian UTF-8 locales known to the
  1531. GNU@tie{}libc, that weighs around 14@tie{}MiB:
  1532. @lisp
  1533. (use-modules (gnu packages base))
  1534. (define my-glibc-locales
  1535. (make-glibc-utf8-locales
  1536. glibc
  1537. #:locales (list "en_CA" "fr_CA" "ik_CA" "iu_CA" "shs_CA")
  1538. #:name "glibc-canadian-utf8-locales"))
  1539. @end lisp
  1540. The @env{GUIX_LOCPATH} variable plays a role similar to @env{LOCPATH}
  1541. (@pxref{Locale Names, @env{LOCPATH},, libc, The GNU C Library Reference
  1542. Manual}). There are two important differences though:
  1543. @enumerate
  1544. @item
  1545. @env{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
  1546. provided by foreign distros. Thus, using @env{GUIX_LOCPATH} allows you
  1547. to make sure the programs of the foreign distro will not end up loading
  1548. incompatible locale data.
  1549. @item
  1550. libc suffixes each entry of @env{GUIX_LOCPATH} with @code{/X.Y}, where
  1551. @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
  1552. should your Guix profile contain a mixture of programs linked against
  1553. different libc version, each libc version will only try to load locale
  1554. data in the right format.
  1555. @end enumerate
  1556. This is important because the locale data format used by different libc
  1557. versions may be incompatible.
  1558. @subsection Name Service Switch
  1559. @cindex name service switch, glibc
  1560. @cindex NSS (name service switch), glibc
  1561. @cindex nscd (name service caching daemon)
  1562. @cindex name service caching daemon (nscd)
  1563. When using Guix on a foreign distro, we @emph{strongly recommend} that
  1564. the system run the GNU C library's @dfn{name service cache daemon},
  1565. @command{nscd}, which should be listening on the
  1566. @file{/var/run/nscd/socket} socket. Failing to do that, applications
  1567. installed with Guix may fail to look up host names or user accounts, or
  1568. may even crash. The next paragraphs explain why.
  1569. @cindex @file{nsswitch.conf}
  1570. The GNU C library implements a @dfn{name service switch} (NSS), which is
  1571. an extensible mechanism for ``name lookups'' in general: host name
  1572. resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
  1573. The GNU C Library Reference Manual}).
  1574. @cindex Network information service (NIS)
  1575. @cindex NIS (Network information service)
  1576. Being extensible, the NSS supports @dfn{plugins}, which provide new name
  1577. lookup implementations: for example, the @code{nss-mdns} plugin allow
  1578. resolution of @code{.local} host names, the @code{nis} plugin allows
  1579. user account lookup using the Network information service (NIS), and so
  1580. on. These extra ``lookup services'' are configured system-wide in
  1581. @file{/etc/nsswitch.conf}, and all the programs running on the system
  1582. honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
  1583. Reference Manual}).
  1584. When they perform a name lookup---for instance by calling the
  1585. @code{getaddrinfo} function in C---applications first try to connect to
  1586. the nscd; on success, nscd performs name lookups on their behalf. If
  1587. the nscd is not running, then they perform the name lookup by
  1588. themselves, by loading the name lookup services into their own address
  1589. space and running it. These name lookup services---the
  1590. @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
  1591. the host system's C library, rather than from the C library the
  1592. application is linked against (the C library coming from Guix).
  1593. And this is where the problem is: if your application is linked against
  1594. Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
  1595. another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
  1596. likely crash or have its name lookups fail unexpectedly.
  1597. Running @command{nscd} on the system, among other advantages, eliminates
  1598. this binary incompatibility problem because those @code{libnss_*.so}
  1599. files are loaded in the @command{nscd} process, not in applications
  1600. themselves.
  1601. @subsection X11 Fonts
  1602. @cindex fonts
  1603. The majority of graphical applications use Fontconfig to locate and load
  1604. fonts and perform X11-client-side rendering. The @code{fontconfig}
  1605. package in Guix looks for fonts in @file{$HOME/.guix-profile} by
  1606. default. Thus, to allow graphical applications installed with Guix to
  1607. display fonts, you have to install fonts with Guix as well. Essential
  1608. font packages include @code{font-ghostscript}, @code{font-dejavu}, and
  1609. @code{font-gnu-freefont}.
  1610. @cindex @code{fc-cache}
  1611. @cindex font cache
  1612. Once you have installed or removed fonts, or when you notice an
  1613. application that does not find fonts, you may need to install Fontconfig
  1614. and to force an update of its font cache by running:
  1615. @example
  1616. guix install fontconfig
  1617. fc-cache -rv
  1618. @end example
  1619. To display text written in Chinese languages, Japanese, or Korean in
  1620. graphical applications, consider installing
  1621. @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
  1622. has multiple outputs, one per language family (@pxref{Packages with
  1623. Multiple Outputs}). For instance, the following command installs fonts
  1624. for Chinese languages:
  1625. @example
  1626. guix install font-adobe-source-han-sans:cn
  1627. @end example
  1628. @cindex @code{xterm}
  1629. Older programs such as @command{xterm} do not use Fontconfig and instead
  1630. rely on server-side font rendering. Such programs require to specify a
  1631. full name of a font using XLFD (X Logical Font Description), like this:
  1632. @example
  1633. -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
  1634. @end example
  1635. To be able to use such full names for the TrueType fonts installed in
  1636. your Guix profile, you need to extend the font path of the X server:
  1637. @c Note: 'xset' does not accept symlinks so the trick below arranges to
  1638. @c get at the real directory. See <https://bugs.gnu.org/30655>.
  1639. @example
  1640. xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
  1641. @end example
  1642. @cindex @code{xlsfonts}
  1643. After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
  1644. to make sure your TrueType fonts are listed there.
  1645. @subsection X.509 Certificates
  1646. @cindex @code{nss-certs}
  1647. The @code{nss-certs} package provides X.509 certificates, which allow
  1648. programs to authenticate Web servers accessed over HTTPS.
  1649. When using Guix on a foreign distro, you can install this package and
  1650. define the relevant environment variables so that packages know where to
  1651. look for certificates. @xref{X.509 Certificates}, for detailed
  1652. information.
  1653. @subsection Emacs Packages
  1654. @cindex @code{emacs}
  1655. When you install Emacs packages with Guix, the Elisp files are placed
  1656. under the @file{share/emacs/site-lisp/} directory of the profile in
  1657. which they are installed. The Elisp libraries are made available to
  1658. Emacs through the @env{EMACSLOADPATH} environment variable, which is
  1659. set when installing Emacs itself.
  1660. Additionally, autoload definitions are automatically evaluated at the
  1661. initialization of Emacs, by the Guix-specific
  1662. @code{guix-emacs-autoload-packages} procedure. If, for some reason, you
  1663. want to avoid auto-loading the Emacs packages installed with Guix, you
  1664. can do so by running Emacs with the @option{--no-site-file} option
  1665. (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
  1666. @node Upgrading Guix
  1667. @section Upgrading Guix
  1668. @cindex Upgrading Guix, on a foreign distro
  1669. To upgrade Guix, run:
  1670. @example
  1671. guix pull
  1672. @end example
  1673. @xref{Invoking guix pull}, for more information.
  1674. @cindex upgrading Guix for the root user, on a foreign distro
  1675. @cindex upgrading the Guix daemon, on a foreign distro
  1676. @cindex @command{guix pull} for the root user, on a foreign distro
  1677. On a foreign distro, you can upgrade the build daemon by running:
  1678. @example
  1679. sudo -i guix pull
  1680. @end example
  1681. @noindent
  1682. followed by (assuming your distro uses the systemd service management
  1683. tool):
  1684. @example
  1685. systemctl restart guix-daemon.service
  1686. @end example
  1687. On Guix System, upgrading the daemon is achieved by reconfiguring the
  1688. system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
  1689. @c TODO What else?
  1690. @c *********************************************************************
  1691. @node System Installation
  1692. @chapter System Installation
  1693. @cindex installing Guix System
  1694. @cindex Guix System, installation
  1695. This section explains how to install Guix System
  1696. on a machine. Guix, as a package manager, can
  1697. also be installed on top of a running GNU/Linux system,
  1698. @pxref{Installation}.
  1699. @ifinfo
  1700. @quotation Note
  1701. @c This paragraph is for people reading this from tty2 of the
  1702. @c installation image.
  1703. You are reading this documentation with an Info reader. For details on
  1704. how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
  1705. link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
  1706. Info}. Hit @kbd{l} afterwards to come back here.
  1707. Alternatively, run @command{info info} in another tty to keep the manual
  1708. available.
  1709. @end quotation
  1710. @end ifinfo
  1711. @menu
  1712. * Limitations:: What you can expect.
  1713. * Hardware Considerations:: Supported hardware.
  1714. * USB Stick and DVD Installation:: Preparing the installation medium.
  1715. * Preparing for Installation:: Networking, partitioning, etc.
  1716. * Guided Graphical Installation:: Easy graphical installation.
  1717. * Manual Installation:: Manual installation for wizards.
  1718. * After System Installation:: When installation succeeded.
  1719. * Installing Guix in a VM:: Guix System playground.
  1720. * Building the Installation Image:: How this comes to be.
  1721. @end menu
  1722. @node Limitations
  1723. @section Limitations
  1724. We consider Guix System to be ready for a wide range of ``desktop'' and server
  1725. use cases. The reliability guarantees it provides---transactional upgrades
  1726. and rollbacks, reproducibility---make it a solid foundation.
  1727. Nevertheless, before you proceed with the installation, be aware of the
  1728. following noteworthy limitations applicable to version @value{VERSION}:
  1729. @itemize
  1730. @item
  1731. More and more system services are provided (@pxref{Services}), but some
  1732. may be missing.
  1733. @item
  1734. GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
  1735. as well as a number of X11 window managers. However, KDE is currently
  1736. missing.
  1737. @end itemize
  1738. More than a disclaimer, this is an invitation to report issues (and success
  1739. stories!), and to join us in improving it. @xref{Contributing}, for more
  1740. info.
  1741. @node Hardware Considerations
  1742. @section Hardware Considerations
  1743. @cindex hardware support on Guix System
  1744. GNU@tie{}Guix focuses on respecting the user's computing freedom. It
  1745. builds around the kernel Linux-libre, which means that only hardware for
  1746. which free software drivers and firmware exist is supported. Nowadays,
  1747. a wide range of off-the-shelf hardware is supported on
  1748. GNU/Linux-libre---from keyboards to graphics cards to scanners and
  1749. Ethernet controllers. Unfortunately, there are still areas where
  1750. hardware vendors deny users control over their own computing, and such
  1751. hardware is not supported on Guix System.
  1752. @cindex WiFi, hardware support
  1753. One of the main areas where free drivers or firmware are lacking is WiFi
  1754. devices. WiFi devices known to work include those using Atheros chips
  1755. (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
  1756. driver, and those using Broadcom/AirForce chips (BCM43xx with
  1757. Wireless-Core Revision 5), which corresponds to the @code{b43-open}
  1758. Linux-libre driver. Free firmware exists for both and is available
  1759. out-of-the-box on Guix System, as part of @code{%base-firmware}
  1760. (@pxref{operating-system Reference, @code{firmware}}).
  1761. @cindex RYF, Respects Your Freedom
  1762. The @uref{https://www.fsf.org/, Free Software Foundation} runs
  1763. @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
  1764. certification program for hardware products that respect your freedom
  1765. and your privacy and ensure that you have control over your device. We
  1766. encourage you to check the list of RYF-certified devices.
  1767. Another useful resource is the @uref{https://www.h-node.org/, H-Node}
  1768. web site. It contains a catalog of hardware devices with information
  1769. about their support in GNU/Linux.
  1770. @node USB Stick and DVD Installation
  1771. @section USB Stick and DVD Installation
  1772. An ISO-9660 installation image that can be written to a USB stick or
  1773. burnt to a DVD can be downloaded from
  1774. @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso},
  1775. where you can replace @code{x86_64-linux} with one of:
  1776. @table @code
  1777. @item x86_64-linux
  1778. for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
  1779. @item i686-linux
  1780. for a 32-bit GNU/Linux system on Intel-compatible CPUs.
  1781. @end table
  1782. @c start duplication of authentication part from ``Binary Installation''
  1783. Make sure to download the associated @file{.sig} file and to verify the
  1784. authenticity of the image against it, along these lines:
  1785. @example
  1786. $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.sig
  1787. $ gpg --verify guix-system-install-@value{VERSION}.x86_64-linux.iso.sig
  1788. @end example
  1789. If that command fails because you do not have the required public key,
  1790. then run this command to import it:
  1791. @example
  1792. $ wget @value{OPENPGP-SIGNING-KEY-URL} \
  1793. -qO - | gpg --import -
  1794. @end example
  1795. @noindent
  1796. and rerun the @code{gpg --verify} command.
  1797. Take note that a warning like ``This key is not certified with a trusted
  1798. signature!'' is normal.
  1799. @c end duplication
  1800. This image contains the tools necessary for an installation.
  1801. It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
  1802. @unnumberedsubsec Copying to a USB Stick
  1803. Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
  1804. its device name. Assuming that the USB stick is known as @file{/dev/sdX},
  1805. copy the image with:
  1806. @example
  1807. dd if=guix-system-install-@value{VERSION}.x86_64-linux.iso of=/dev/sdX status=progress
  1808. sync
  1809. @end example
  1810. Access to @file{/dev/sdX} usually requires root privileges.
  1811. @unnumberedsubsec Burning on a DVD
  1812. Insert a blank DVD into your machine, and determine
  1813. its device name. Assuming that the DVD drive is known as @file{/dev/srX},
  1814. copy the image with:
  1815. @example
  1816. growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.x86_64-linux.iso
  1817. @end example
  1818. Access to @file{/dev/srX} usually requires root privileges.
  1819. @unnumberedsubsec Booting
  1820. Once this is done, you should be able to reboot the system and boot from
  1821. the USB stick or DVD@. The latter usually requires you to get in the
  1822. BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
  1823. In order to boot from Libreboot, switch to the command mode by pressing
  1824. the @kbd{c} key and type @command{search_grub usb}.
  1825. @xref{Installing Guix in a VM}, if, instead, you would like to install
  1826. Guix System in a virtual machine (VM).
  1827. @node Preparing for Installation
  1828. @section Preparing for Installation
  1829. Once you have booted, you can use the guided graphical installer, which makes
  1830. it easy to get started (@pxref{Guided Graphical Installation}). Alternatively,
  1831. if you are already familiar with GNU/Linux and if you want more control than
  1832. what the graphical installer provides, you can choose the ``manual''
  1833. installation process (@pxref{Manual Installation}).
  1834. The graphical installer is available on TTY1. You can obtain root shells on
  1835. TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
  1836. this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
  1837. is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
  1838. Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
  1839. which allows you to select text with the left mouse button and to paste it
  1840. with the middle button.
  1841. @quotation Note
  1842. Installation requires access to the Internet so that any missing
  1843. dependencies of your system configuration can be downloaded. See the
  1844. ``Networking'' section below.
  1845. @end quotation
  1846. @node Guided Graphical Installation
  1847. @section Guided Graphical Installation
  1848. The graphical installer is a text-based user interface. It will guide you,
  1849. with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
  1850. The first dialog boxes allow you to set up the system as you use it during the
  1851. installation: you can choose the language, keyboard layout, and set up
  1852. networking, which will be used during the installation. The image below shows
  1853. the networking dialog.
  1854. @image{images/installer-network,5in,, networking setup with the graphical installer}
  1855. Later steps allow you to partition your hard disk, as shown in the image
  1856. below, to choose whether or not to use encrypted file systems, to enter the
  1857. host name and root password, and to create an additional account, among other
  1858. things.
  1859. @image{images/installer-partitions,5in,, partitioning with the graphical installer}
  1860. Note that, at any time, the installer allows you to exit the current
  1861. installation step and resume at a previous step, as show in the image below.
  1862. @image{images/installer-resume,5in,, resuming the installation process}
  1863. Once you're done, the installer produces an operating system configuration and
  1864. displays it (@pxref{Using the Configuration System}). At that point you can
  1865. hit ``OK'' and installation will proceed. On success, you can reboot into the
  1866. new system and enjoy. @xref{After System Installation}, for what's next!
  1867. @node Manual Installation
  1868. @section Manual Installation
  1869. This section describes how you would ``manually'' install GNU@tie{}Guix System
  1870. on your machine. This option requires familiarity with GNU/Linux, with the
  1871. shell, and with common administration tools. If you think this is not for
  1872. you, consider using the guided graphical installer (@pxref{Guided Graphical
  1873. Installation}).
  1874. The installation system provides root shells on TTYs 3 to 6; press
  1875. @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
  1876. many common tools needed to install the system. But it is also a full-blown
  1877. Guix System, which means that you can install additional packages, should you
  1878. need it, using @command{guix package} (@pxref{Invoking guix package}).
  1879. @menu
  1880. * Keyboard Layout and Networking and Partitioning:: Initial setup.
  1881. * Proceeding with the Installation:: Installing.
  1882. @end menu
  1883. @node Keyboard Layout and Networking and Partitioning
  1884. @subsection Keyboard Layout, Networking, and Partitioning
  1885. Before you can install the system, you may want to adjust the keyboard layout,
  1886. set up networking, and partition your target hard disk. This section will
  1887. guide you through this.
  1888. @subsubsection Keyboard Layout
  1889. @cindex keyboard layout
  1890. The installation image uses the US qwerty keyboard layout. If you want
  1891. to change it, you can use the @command{loadkeys} command. For example,
  1892. the following command selects the Dvorak keyboard layout:
  1893. @example
  1894. loadkeys dvorak
  1895. @end example
  1896. See the files under @file{/run/current-system/profile/share/keymaps} for
  1897. a list of available keyboard layouts. Run @command{man loadkeys} for
  1898. more information.
  1899. @subsubsection Networking
  1900. Run the following command to see what your network interfaces are called:
  1901. @example
  1902. ifconfig -a
  1903. @end example
  1904. @noindent
  1905. @dots{} or, using the GNU/Linux-specific @command{ip} command:
  1906. @example
  1907. ip address
  1908. @end example
  1909. @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
  1910. Wired interfaces have a name starting with @samp{e}; for example, the
  1911. interface corresponding to the first on-board Ethernet controller is
  1912. called @samp{eno1}. Wireless interfaces have a name starting with
  1913. @samp{w}, like @samp{w1p2s0}.
  1914. @table @asis
  1915. @item Wired connection
  1916. To configure a wired network run the following command, substituting
  1917. @var{interface} with the name of the wired interface you want to use.
  1918. @example
  1919. ifconfig @var{interface} up
  1920. @end example
  1921. @noindent
  1922. @dots{} or, using the GNU/Linux-specific @command{ip} command:
  1923. @example
  1924. ip link set @var{interface} up
  1925. @end example
  1926. @item Wireless connection
  1927. @cindex wireless
  1928. @cindex WiFi
  1929. To configure wireless networking, you can create a configuration file
  1930. for the @command{wpa_supplicant} configuration tool (its location is not
  1931. important) using one of the available text editors such as
  1932. @command{nano}:
  1933. @example
  1934. nano wpa_supplicant.conf
  1935. @end example
  1936. As an example, the following stanza can go to this file and will work
  1937. for many wireless networks, provided you give the actual SSID and
  1938. passphrase for the network you are connecting to:
  1939. @example
  1940. network=@{
  1941. ssid="@var{my-ssid}"
  1942. key_mgmt=WPA-PSK
  1943. psk="the network's secret passphrase"
  1944. @}
  1945. @end example
  1946. Start the wireless service and run it in the background with the
  1947. following command (substitute @var{interface} with the name of the
  1948. network interface you want to use):
  1949. @example
  1950. wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
  1951. @end example
  1952. Run @command{man wpa_supplicant} for more information.
  1953. @end table
  1954. @cindex DHCP
  1955. At this point, you need to acquire an IP address. On a network where IP
  1956. addresses are automatically assigned @i{via} DHCP, you can run:
  1957. @example
  1958. dhclient -v @var{interface}
  1959. @end example
  1960. Try to ping a server to see if networking is up and running:
  1961. @example
  1962. ping -c 3 gnu.org
  1963. @end example
  1964. Setting up network access is almost always a requirement because the
  1965. image does not contain all the software and tools that may be needed.
  1966. @cindex proxy, during system installation
  1967. If you need HTTP and HTTPS access to go through a proxy, run the
  1968. following command:
  1969. @example
  1970. herd set-http-proxy guix-daemon @var{URL}
  1971. @end example
  1972. @noindent
  1973. where @var{URL} is the proxy URL, for example
  1974. @code{http://example.org:8118}.
  1975. @cindex installing over SSH
  1976. If you want to, you can continue the installation remotely by starting
  1977. an SSH server:
  1978. @example
  1979. herd start ssh-daemon
  1980. @end example
  1981. Make sure to either set a password with @command{passwd}, or configure
  1982. OpenSSH public key authentication before logging in.
  1983. @subsubsection Disk Partitioning
  1984. Unless this has already been done, the next step is to partition, and
  1985. then format the target partition(s).
  1986. The installation image includes several partitioning tools, including
  1987. Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
  1988. @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
  1989. the partition layout you want:
  1990. @example
  1991. cfdisk
  1992. @end example
  1993. If your disk uses the GUID Partition Table (GPT) format and you plan to
  1994. install BIOS-based GRUB (which is the default), make sure a BIOS Boot
  1995. Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
  1996. manual}).
  1997. @cindex EFI, installation
  1998. @cindex UEFI, installation
  1999. @cindex ESP, EFI system partition
  2000. If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
  2001. (ESP) is required. This partition can be mounted at @file{/boot/efi} for
  2002. instance and must have the @code{esp} flag set. E.g., for @command{parted}:
  2003. @example
  2004. parted /dev/sda set 1 esp on
  2005. @end example
  2006. @quotation Note
  2007. @vindex grub-bootloader
  2008. @vindex grub-efi-bootloader
  2009. Unsure whether to use EFI- or BIOS-based GRUB? If the directory
  2010. @file{/sys/firmware/efi} exists in the installation image, then you should
  2011. probably perform an EFI installation, using @code{grub-efi-bootloader}.
  2012. Otherwise you should use the BIOS-based GRUB, known as
  2013. @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
  2014. bootloaders.
  2015. @end quotation
  2016. Once you are done partitioning the target hard disk drive, you have to
  2017. create a file system on the relevant partition(s)@footnote{Currently
  2018. Guix System only supports ext4, btrfs, JFS, F2FS, and XFS file systems. In
  2019. particular, code that reads file system UUIDs and labels only works for these
  2020. file system types.}. For the ESP, if you have one and assuming it is
  2021. @file{/dev/sda1}, run:
  2022. @example
  2023. mkfs.fat -F32 /dev/sda1
  2024. @end example
  2025. For the root file system, ext4 is the most widely used format. Other
  2026. file systems, such as Btrfs, support compression, which is reported to
  2027. nicely complement file deduplication that the daemon performs
  2028. independently of the file system (@pxref{Invoking guix-daemon,
  2029. deduplication}).
  2030. Preferably, assign file systems a label so that you can easily and
  2031. reliably refer to them in @code{file-system} declarations (@pxref{File
  2032. Systems}). This is typically done using the @code{-L} option of
  2033. @command{mkfs.ext4} and related commands. So, assuming the target root
  2034. partition lives at @file{/dev/sda2}, a file system with the label
  2035. @code{my-root} can be created with:
  2036. @example
  2037. mkfs.ext4 -L my-root /dev/sda2
  2038. @end example
  2039. @cindex encrypted disk
  2040. If you are instead planning to encrypt the root partition, you can use
  2041. the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
  2042. @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
  2043. @code{man cryptsetup}} for more information).
  2044. @quotation Warning
  2045. Note that GRUB can unlock LUKS2 devices since version 2.06, but only
  2046. supports the PBKDF2 key derivation function, which is not the default
  2047. for @command{cryptsetup luksFormat}. You can check which key derivation
  2048. function is being used by a device by running @command{cryptsetup
  2049. luksDump @var{device}}, and looking for the PBKDF field of your
  2050. keyslots.
  2051. @end quotation
  2052. Assuming you want to store the root partition on @file{/dev/sda2}, the
  2053. command sequence to format it as a LUKS2 partition would be along these
  2054. lines:
  2055. @example
  2056. cryptsetup luksFormat --type luks2 --pbkdf pbkdf2 /dev/sda2
  2057. cryptsetup open /dev/sda2 my-partition
  2058. mkfs.ext4 -L my-root /dev/mapper/my-partition
  2059. @end example
  2060. Once that is done, mount the target file system under @file{/mnt}
  2061. with a command like (again, assuming @code{my-root} is the label of the
  2062. root file system):
  2063. @example
  2064. mount LABEL=my-root /mnt
  2065. @end example
  2066. Also mount any other file systems you would like to use on the target
  2067. system relative to this path. If you have opted for @file{/boot/efi} as an
  2068. EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
  2069. found by @code{guix system init} afterwards.
  2070. Finally, if you plan to use one or more swap partitions (@pxref{Swap
  2071. Space}), make sure to initialize them with @command{mkswap}. Assuming
  2072. you have one swap partition on @file{/dev/sda3}, you would run:
  2073. @example
  2074. mkswap /dev/sda3
  2075. swapon /dev/sda3
  2076. @end example
  2077. Alternatively, you may use a swap file. For example, assuming that in
  2078. the new system you want to use the file @file{/swapfile} as a swap file,
  2079. you would run@footnote{This example will work for many types of file
  2080. systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
  2081. btrfs), the required steps may be different. For details, see the
  2082. manual pages for @command{mkswap} and @command{swapon}.}:
  2083. @example
  2084. # This is 10 GiB of swap space. Adjust "count" to change the size.
  2085. dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
  2086. # For security, make the file readable and writable only by root.
  2087. chmod 600 /mnt/swapfile
  2088. mkswap /mnt/swapfile
  2089. swapon /mnt/swapfile
  2090. @end example
  2091. Note that if you have encrypted the root partition and created a swap
  2092. file in its file system as described above, then the encryption also
  2093. protects the swap file, just like any other file in that file system.
  2094. @node Proceeding with the Installation
  2095. @subsection Proceeding with the Installation
  2096. With the target partitions ready and the target root mounted on
  2097. @file{/mnt}, we're ready to go. First, run:
  2098. @example
  2099. herd start cow-store /mnt
  2100. @end example
  2101. This makes @file{/gnu/store} copy-on-write, such that packages added to it
  2102. during the installation phase are written to the target disk on @file{/mnt}
  2103. rather than kept in memory. This is necessary because the first phase of
  2104. the @command{guix system init} command (see below) entails downloads or
  2105. builds to @file{/gnu/store} which, initially, is an in-memory file system.
  2106. Next, you have to edit a file and
  2107. provide the declaration of the operating system to be installed. To
  2108. that end, the installation system comes with three text editors. We
  2109. recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
  2110. supports syntax highlighting and parentheses matching; other editors
  2111. include mg (an Emacs clone), and
  2112. nvi (a clone of the original BSD @command{vi} editor).
  2113. We strongly recommend storing that file on the target root file system, say,
  2114. as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
  2115. configuration file once you have rebooted into the newly-installed system.
  2116. @xref{Using the Configuration System}, for an overview of the
  2117. configuration file. The example configurations discussed in that
  2118. section are available under @file{/etc/configuration} in the
  2119. installation image. Thus, to get started with a system configuration
  2120. providing a graphical display server (a ``desktop'' system), you can run
  2121. something along these lines:
  2122. @example
  2123. # mkdir /mnt/etc
  2124. # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
  2125. # nano /mnt/etc/config.scm
  2126. @end example
  2127. You should pay attention to what your configuration file contains, and
  2128. in particular:
  2129. @itemize
  2130. @item
  2131. Make sure the @code{bootloader-configuration} form refers to the targets
  2132. you want to install GRUB on. It should mention @code{grub-bootloader}
  2133. if you are installing GRUB in the legacy way, or
  2134. @code{grub-efi-bootloader} for newer UEFI systems. For legacy systems,
  2135. the @code{targets} field contain the names of the devices, like
  2136. @code{(list "/dev/sda")}; for UEFI systems it names the paths to mounted
  2137. EFI partitions, like @code{(list "/boot/efi")}; do make sure the paths
  2138. are currently mounted and a @code{file-system} entry is specified in
  2139. your configuration.
  2140. @item
  2141. Be sure that your file system labels match the value of their respective
  2142. @code{device} fields in your @code{file-system} configuration, assuming
  2143. your @code{file-system} configuration uses the @code{file-system-label}
  2144. procedure in its @code{device} field.
  2145. @item
  2146. If there are encrypted or RAID partitions, make sure to add a
  2147. @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
  2148. @end itemize
  2149. Once you are done preparing the configuration file, the new system must
  2150. be initialized (remember that the target root file system is mounted
  2151. under @file{/mnt}):
  2152. @example
  2153. guix system init /mnt/etc/config.scm /mnt
  2154. @end example
  2155. @noindent
  2156. This copies all the necessary files and installs GRUB on
  2157. @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
  2158. more information, @pxref{Invoking guix system}. This command may trigger
  2159. downloads or builds of missing packages, which can take some time.
  2160. Once that command has completed---and hopefully succeeded!---you can run
  2161. @command{reboot} and boot into the new system. The @code{root} password
  2162. in the new system is initially empty; other users' passwords need to be
  2163. initialized by running the @command{passwd} command as @code{root},
  2164. unless your configuration specifies otherwise
  2165. (@pxref{user-account-password, user account passwords}).
  2166. @xref{After System Installation}, for what's next!
  2167. @node After System Installation
  2168. @section After System Installation
  2169. Success, you've now booted into Guix System! From then on, you can update the
  2170. system whenever you want by running, say:
  2171. @example
  2172. guix pull
  2173. sudo guix system reconfigure /etc/config.scm
  2174. @end example
  2175. @noindent
  2176. This builds a new system generation with the latest packages and services
  2177. (@pxref{Invoking guix system}). We recommend doing that regularly so that
  2178. your system includes the latest security updates (@pxref{Security Updates}).
  2179. @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
  2180. @quotation Note
  2181. @cindex sudo vs. @command{guix pull}
  2182. Note that @command{sudo guix} runs your user's @command{guix} command and
  2183. @emph{not} root's, because @command{sudo} leaves @env{PATH} unchanged. To
  2184. explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
  2185. The difference matters here, because @command{guix pull} updates
  2186. the @command{guix} command and package definitions only for the user it is run
  2187. as. This means that if you choose to use @command{guix system reconfigure} in
  2188. root's login shell, you'll need to @command{guix pull} separately.
  2189. @end quotation
  2190. Now, @pxref{Getting Started}, and
  2191. join us on @code{#guix} on the Libera Chat IRC network or on
  2192. @email{guix-devel@@gnu.org} to share your experience!
  2193. @node Installing Guix in a VM
  2194. @section Installing Guix in a Virtual Machine
  2195. @cindex virtual machine, Guix System installation
  2196. @cindex virtual private server (VPS)
  2197. @cindex VPS (virtual private server)
  2198. If you'd like to install Guix System in a virtual machine (VM) or on a
  2199. virtual private server (VPS) rather than on your beloved machine, this
  2200. section is for you.
  2201. To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
  2202. disk image, follow these steps:
  2203. @enumerate
  2204. @item
  2205. First, retrieve and decompress the Guix system installation image as
  2206. described previously (@pxref{USB Stick and DVD Installation}).
  2207. @item
  2208. Create a disk image that will hold the installed system. To make a
  2209. qcow2-formatted disk image, use the @command{qemu-img} command:
  2210. @example
  2211. qemu-img create -f qcow2 guix-system.img 50G
  2212. @end example
  2213. The resulting file will be much smaller than 50 GB (typically less than
  2214. 1 MB), but it will grow as the virtualized storage device is filled up.
  2215. @item
  2216. Boot the USB installation image in an VM:
  2217. @example
  2218. qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
  2219. -nic user,model=virtio-net-pci -boot menu=on,order=d \
  2220. -drive file=guix-system.img \
  2221. -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
  2222. @end example
  2223. @code{-enable-kvm} is optional, but significantly improves performance,
  2224. @pxref{Running Guix in a VM}.
  2225. @item
  2226. You're now root in the VM, proceed with the installation process.
  2227. @xref{Preparing for Installation}, and follow the instructions.
  2228. @end enumerate
  2229. Once installation is complete, you can boot the system that's on your
  2230. @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
  2231. that.
  2232. @node Building the Installation Image
  2233. @section Building the Installation Image
  2234. @cindex installation image
  2235. The installation image described above was built using the @command{guix
  2236. system} command, specifically:
  2237. @example
  2238. guix system image -t iso9660 gnu/system/install.scm
  2239. @end example
  2240. Have a look at @file{gnu/system/install.scm} in the source tree,
  2241. and see also @ref{Invoking guix system} for more information
  2242. about the installation image.
  2243. @section Building the Installation Image for ARM Boards
  2244. Many ARM boards require a specific variant of the
  2245. @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
  2246. If you build a disk image and the bootloader is not available otherwise
  2247. (on another boot drive etc), it's advisable to build an image that
  2248. includes the bootloader, specifically:
  2249. @example
  2250. guix system image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
  2251. @end example
  2252. @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
  2253. board, a list of possible boards will be printed.
  2254. @c *********************************************************************
  2255. @node Getting Started
  2256. @chapter Getting Started
  2257. Presumably, you've reached this section because either you have
  2258. installed Guix on top of another distribution (@pxref{Installation}), or
  2259. you've installed the standalone Guix System (@pxref{System
  2260. Installation}). It's time for you to get started using Guix and this
  2261. section aims to help you do that and give you a feel of what it's like.
  2262. Guix is about installing software, so probably the first thing you'll
  2263. want to do is to actually look for software. Let's say you're looking
  2264. for a text editor, you can run:
  2265. @example
  2266. guix search text editor
  2267. @end example
  2268. This command shows you a number of matching @dfn{packages}, each time
  2269. showing the package's name, version, a description, and additional info.
  2270. Once you've found out the one you want to use, let's say Emacs (ah ha!),
  2271. you can go ahead and install it (run this command as a regular user,
  2272. @emph{no need for root privileges}!):
  2273. @example
  2274. guix install emacs
  2275. @end example
  2276. @cindex profile
  2277. You've installed your first package, congrats! The package is now
  2278. visible in your default @dfn{profile}, @file{$HOME/.guix-profile}---a
  2279. profile is a directory containing installed packages.
  2280. In the process, you've
  2281. probably noticed that Guix downloaded pre-built binaries; or, if you
  2282. explicitly chose to @emph{not} use pre-built binaries, then probably
  2283. Guix is still building software (@pxref{Substitutes}, for more info).
  2284. Unless you're using Guix System, the @command{guix install} command must
  2285. have printed this hint:
  2286. @example
  2287. hint: Consider setting the necessary environment variables by running:
  2288. GUIX_PROFILE="$HOME/.guix-profile"
  2289. . "$GUIX_PROFILE/etc/profile"
  2290. Alternately, see `guix package --search-paths -p "$HOME/.guix-profile"'.
  2291. @end example
  2292. Indeed, you must now tell your shell where @command{emacs} and other
  2293. programs installed with Guix are to be found. Pasting the two lines
  2294. above will do just that: it will add
  2295. @code{$HOME/.guix-profile/bin}---which is where the installed package
  2296. is---to the @code{PATH} environment variable. You can paste these two
  2297. lines in your shell so they take effect right away, but more importantly
  2298. you should add them to @file{~/.bash_profile} (or equivalent file if you
  2299. do not use Bash) so that environment variables are set next time you
  2300. spawn a shell. You only need to do this once and other search paths
  2301. environment variables will be taken care of similarly---e.g., if you
  2302. eventually install @code{python} and Python libraries,
  2303. @env{GUIX_PYTHONPATH} will be defined.
  2304. You can go on installing packages at your will. To list installed
  2305. packages, run:
  2306. @example
  2307. guix package --list-installed
  2308. @end example
  2309. To remove a package, you would unsurprisingly run @command{guix remove}.
  2310. A distinguishing feature is the ability to @dfn{roll back} any operation
  2311. you made---installation, removal, upgrade---by simply typing:
  2312. @example
  2313. guix package --roll-back
  2314. @end example
  2315. This is because each operation is in fact a @dfn{transaction} that
  2316. creates a new @dfn{generation}. These generations and the difference
  2317. between them can be displayed by running:
  2318. @example
  2319. guix package --list-generations
  2320. @end example
  2321. Now you know the basics of package management!
  2322. @quotation Going further
  2323. @xref{Package Management}, for more about package management. You may
  2324. like @dfn{declarative} package management with @command{guix package
  2325. --manifest}, managing separate @dfn{profiles} with @option{--profile},
  2326. deleting old generations, collecting garbage, and other nifty features
  2327. that will come in handy as you become more familiar with Guix. If you
  2328. are a developer, @pxref{Development} for additional tools. And if
  2329. you're curious, @pxref{Features}, to peek under the hood.
  2330. @end quotation
  2331. Once you've installed a set of packages, you will want to periodically
  2332. @emph{upgrade} them to the latest and greatest version. To do that, you
  2333. will first pull the latest revision of Guix and its package collection:
  2334. @example
  2335. guix pull
  2336. @end example
  2337. The end result is a new @command{guix} command, under
  2338. @file{~/.config/guix/current/bin}. Unless you're on Guix System, the
  2339. first time you run @command{guix pull}, be sure to follow the hint that
  2340. the command prints and, similar to what we saw above, paste these two
  2341. lines in your terminal and @file{.bash_profile}:
  2342. @example
  2343. GUIX_PROFILE="$HOME/.config/guix/current"
  2344. . "$GUIX_PROFILE/etc/profile"
  2345. @end example
  2346. @noindent
  2347. You must also instruct your shell to point to this new @command{guix}:
  2348. @example
  2349. hash guix
  2350. @end example
  2351. At this point, you're running a brand new Guix. You can thus go ahead
  2352. and actually upgrade all the packages you previously installed:
  2353. @example
  2354. guix upgrade
  2355. @end example
  2356. As you run this command, you will see that binaries are downloaded (or
  2357. perhaps some packages are built), and eventually you end up with the
  2358. upgraded packages. Should one of these upgraded packages not be to your
  2359. liking, remember you can always roll back!
  2360. You can display the exact revision of Guix you're currently using by
  2361. running:
  2362. @example
  2363. guix describe
  2364. @end example
  2365. The information it displays is @emph{all it takes to reproduce the exact
  2366. same Guix}, be it at a different point in time or on a different
  2367. machine.
  2368. @quotation Going further
  2369. @xref{Invoking guix pull}, for more information. @xref{Channels}, on
  2370. how to specify additional @dfn{channels} to pull packages from, how to
  2371. replicate Guix, and more. You may also find @command{time-machine}
  2372. handy (@pxref{Invoking guix time-machine}).
  2373. @end quotation
  2374. If you installed Guix System, one of the first things you'll want to do
  2375. is to upgrade your system. Once you've run @command{guix pull} to get
  2376. the latest Guix, you can upgrade the system like this:
  2377. @example
  2378. sudo guix system reconfigure /etc/config.scm
  2379. @end example
  2380. Upon completion, the system runs the latest versions of its software
  2381. packages. When you eventually reboot, you'll notice a sub-menu in the
  2382. bootloader that reads ``Old system generations'': it's what allows you
  2383. to boot @emph{an older generation of your system}, should the latest
  2384. generation be ``broken'' or otherwise unsatisfying. Just like for
  2385. packages, you can always @emph{roll back} to a previous generation
  2386. @emph{of the whole system}:
  2387. @example
  2388. sudo guix system roll-back
  2389. @end example
  2390. There are many things you'll probably want to tweak on your system:
  2391. adding new user accounts, adding new system services, fiddling with the
  2392. configuration of those services, etc. The system configuration is
  2393. @emph{entirely} described in the @file{/etc/config.scm} file.
  2394. @xref{Using the Configuration System}, to learn how to change it.
  2395. Now you know enough to get started!
  2396. @quotation Resources
  2397. The rest of this manual provides a reference for all things Guix. Here
  2398. are some additional resources you may find useful:
  2399. @itemize
  2400. @item
  2401. @xref{Top,,, guix-cookbook, The GNU Guix Cookbook}, for a list of
  2402. ``how-to'' style of recipes for a variety of applications.
  2403. @item
  2404. The @uref{https://guix.gnu.org/guix-refcard.pdf, GNU Guix Reference
  2405. Card} lists in two pages most of the commands and options you'll ever
  2406. need.
  2407. @item
  2408. The web site contains @uref{https://guix.gnu.org/en/videos/,
  2409. instructional videos} covering topics such as everyday use of Guix, how
  2410. to get help, and how to become a contributor.
  2411. @item
  2412. @xref{Documentation}, to learn how to access documentation on your
  2413. computer.
  2414. @end itemize
  2415. We hope you will enjoy Guix as much as the community enjoys building it!
  2416. @end quotation
  2417. @c *********************************************************************
  2418. @node Package Management
  2419. @chapter Package Management
  2420. @cindex packages
  2421. The purpose of GNU Guix is to allow users to easily install, upgrade, and
  2422. remove software packages, without having to know about their build
  2423. procedures or dependencies. Guix also goes beyond this obvious set of
  2424. features.
  2425. This chapter describes the main features of Guix, as well as the
  2426. package management tools it provides. Along with the command-line
  2427. interface described below (@pxref{Invoking guix package, @code{guix
  2428. package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
  2429. emacs-guix, The Emacs-Guix Reference Manual}), after installing
  2430. @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
  2431. with it):
  2432. @example
  2433. guix install emacs-guix
  2434. @end example
  2435. @menu
  2436. * Features:: How Guix will make your life brighter.
  2437. * Invoking guix package:: Package installation, removal, etc.
  2438. * Substitutes:: Downloading pre-built binaries.
  2439. * Packages with Multiple Outputs:: Single source package, multiple outputs.
  2440. * Invoking guix gc:: Running the garbage collector.
  2441. * Invoking guix pull:: Fetching the latest Guix and distribution.
  2442. * Invoking guix time-machine:: Running an older revision of Guix.
  2443. * Inferiors:: Interacting with another revision of Guix.
  2444. * Invoking guix describe:: Display information about your Guix revision.
  2445. * Invoking guix archive:: Exporting and importing store files.
  2446. @end menu
  2447. @node Features
  2448. @section Features
  2449. Here we assume you've already made your first steps with Guix
  2450. (@pxref{Getting Started}) and would like to get an overview about what's
  2451. going on under the hood.
  2452. When using Guix, each package ends up in the @dfn{package store}, in its
  2453. own directory---something that resembles
  2454. @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
  2455. Instead of referring to these directories, users have their own
  2456. @dfn{profile}, which points to the packages that they actually want to
  2457. use. These profiles are stored within each user's home directory, at
  2458. @code{$HOME/.guix-profile}.
  2459. For example, @code{alice} installs GCC 4.7.2. As a result,
  2460. @file{/home/alice/.guix-profile/bin/gcc} points to
  2461. @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
  2462. @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
  2463. simply continues to point to
  2464. @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
  2465. coexist on the same system without any interference.
  2466. The @command{guix package} command is the central tool to manage
  2467. packages (@pxref{Invoking guix package}). It operates on the per-user
  2468. profiles, and can be used @emph{with normal user privileges}.
  2469. @cindex transactions
  2470. The command provides the obvious install, remove, and upgrade
  2471. operations. Each invocation is actually a @emph{transaction}: either
  2472. the specified operation succeeds, or nothing happens. Thus, if the
  2473. @command{guix package} process is terminated during the transaction,
  2474. or if a power outage occurs during the transaction, then the user's
  2475. profile remains in its previous state, and remains usable.
  2476. In addition, any package transaction may be @emph{rolled back}. So, if,
  2477. for example, an upgrade installs a new version of a package that turns
  2478. out to have a serious bug, users may roll back to the previous instance
  2479. of their profile, which was known to work well. Similarly, the global
  2480. system configuration on Guix is subject to
  2481. transactional upgrades and roll-back
  2482. (@pxref{Using the Configuration System}).
  2483. All packages in the package store may be @emph{garbage-collected}.
  2484. Guix can determine which packages are still referenced by user
  2485. profiles, and remove those that are provably no longer referenced
  2486. (@pxref{Invoking guix gc}). Users may also explicitly remove old
  2487. generations of their profile so that the packages they refer to can be
  2488. collected.
  2489. @cindex reproducibility
  2490. @cindex reproducible builds
  2491. Guix takes a @dfn{purely functional} approach to package
  2492. management, as described in the introduction (@pxref{Introduction}).
  2493. Each @file{/gnu/store} package directory name contains a hash of all the
  2494. inputs that were used to build that package---compiler, libraries, build
  2495. scripts, etc. This direct correspondence allows users to make sure a
  2496. given package installation matches the current state of their
  2497. distribution. It also helps maximize @dfn{build reproducibility}:
  2498. thanks to the isolated build environments that are used, a given build
  2499. is likely to yield bit-identical files when performed on different
  2500. machines (@pxref{Invoking guix-daemon, container}).
  2501. @cindex substitutes
  2502. This foundation allows Guix to support @dfn{transparent binary/source
  2503. deployment}. When a pre-built binary for a @file{/gnu/store} item is
  2504. available from an external source---a @dfn{substitute}, Guix just
  2505. downloads it and unpacks it;
  2506. otherwise, it builds the package from source, locally
  2507. (@pxref{Substitutes}). Because build results are usually bit-for-bit
  2508. reproducible, users do not have to trust servers that provide
  2509. substitutes: they can force a local build and @emph{challenge} providers
  2510. (@pxref{Invoking guix challenge}).
  2511. Control over the build environment is a feature that is also useful for
  2512. developers. The @command{guix shell} command allows developers of
  2513. a package to quickly set up the right development environment for their
  2514. package, without having to manually install the dependencies of the
  2515. package into their profile (@pxref{Invoking guix shell}).
  2516. @cindex replication, of software environments
  2517. @cindex provenance tracking, of software artifacts
  2518. All of Guix and its package definitions is version-controlled, and
  2519. @command{guix pull} allows you to ``travel in time'' on the history of Guix
  2520. itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
  2521. Guix instance on a different machine or at a later point in time, which in
  2522. turn allows you to @emph{replicate complete software environments}, while
  2523. retaining precise @dfn{provenance tracking} of the software.
  2524. @node Invoking guix package
  2525. @section Invoking @command{guix package}
  2526. @cindex installing packages
  2527. @cindex removing packages
  2528. @cindex package installation
  2529. @cindex package removal
  2530. @cindex profile
  2531. The @command{guix package} command is the tool that allows users to
  2532. install, upgrade, and remove packages, as well as rolling back to
  2533. previous configurations. These operations work on a user
  2534. @dfn{profile}---a directory of installed packages. Each user has a
  2535. default profile in @file{$HOME/.guix-profile}.
  2536. The command operates only on the user's own profile,
  2537. and works with normal user privileges (@pxref{Features}). Its syntax
  2538. is:
  2539. @example
  2540. guix package @var{options}
  2541. @end example
  2542. @cindex transactions
  2543. Primarily, @var{options} specifies the operations to be performed during
  2544. the transaction. Upon completion, a new profile is created, but
  2545. previous @dfn{generations} of the profile remain available, should the user
  2546. want to roll back.
  2547. For example, to remove @code{lua} and install @code{guile} and
  2548. @code{guile-cairo} in a single transaction:
  2549. @example
  2550. guix package -r lua -i guile guile-cairo
  2551. @end example
  2552. @cindex aliases, for @command{guix package}
  2553. For your convenience, we also provide the following aliases:
  2554. @itemize
  2555. @item
  2556. @command{guix search} is an alias for @command{guix package -s},
  2557. @item
  2558. @command{guix install} is an alias for @command{guix package -i},
  2559. @item
  2560. @command{guix remove} is an alias for @command{guix package -r},
  2561. @item
  2562. @command{guix upgrade} is an alias for @command{guix package -u},
  2563. @item
  2564. and @command{guix show} is an alias for @command{guix package --show=}.
  2565. @end itemize
  2566. These aliases are less expressive than @command{guix package} and provide
  2567. fewer options, so in some cases you'll probably want to use @command{guix
  2568. package} directly.
  2569. @command{guix package} also supports a @dfn{declarative approach}
  2570. whereby the user specifies the exact set of packages to be available and
  2571. passes it @i{via} the @option{--manifest} option
  2572. (@pxref{profile-manifest, @option{--manifest}}).
  2573. @cindex profile
  2574. For each user, a symlink to the user's default profile is automatically
  2575. created in @file{$HOME/.guix-profile}. This symlink always points to the
  2576. current generation of the user's default profile. Thus, users can add
  2577. @file{$HOME/.guix-profile/bin} to their @env{PATH} environment
  2578. variable, and so on.
  2579. @cindex search paths
  2580. If you are not using Guix System, consider adding the
  2581. following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
  2582. Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
  2583. shells get all the right environment variable definitions:
  2584. @example
  2585. GUIX_PROFILE="$HOME/.guix-profile" ; \
  2586. source "$GUIX_PROFILE/etc/profile"
  2587. @end example
  2588. In a multi-user setup, user profiles are stored in a place registered as
  2589. a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
  2590. to (@pxref{Invoking guix gc}). That directory is normally
  2591. @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
  2592. @var{localstatedir} is the value passed to @code{configure} as
  2593. @option{--localstatedir}, and @var{user} is the user name. The
  2594. @file{per-user} directory is created when @command{guix-daemon} is
  2595. started, and the @var{user} sub-directory is created by @command{guix
  2596. package}.
  2597. The @var{options} can be among the following:
  2598. @table @code
  2599. @item --install=@var{package} @dots{}
  2600. @itemx -i @var{package} @dots{}
  2601. Install the specified @var{package}s.
  2602. Each @var{package} may specify either a simple package name, such as
  2603. @code{guile}, or a package name followed by an at-sign and version number,
  2604. such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
  2605. case, the newest version prefixed by @code{1.8} is selected).
  2606. If no version number is specified, the
  2607. newest available version will be selected. In addition, @var{package}
  2608. may contain a colon, followed by the name of one of the outputs of the
  2609. package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
  2610. (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
  2611. name (and optionally version) are searched for among the GNU
  2612. distribution modules (@pxref{Package Modules}).
  2613. @cindex propagated inputs
  2614. Sometimes packages have @dfn{propagated inputs}: these are dependencies
  2615. that automatically get installed along with the required package
  2616. (@pxref{package-propagated-inputs, @code{propagated-inputs} in
  2617. @code{package} objects}, for information about propagated inputs in
  2618. package definitions).
  2619. @anchor{package-cmd-propagated-inputs}
  2620. An example is the GNU MPC library: its C header files refer to those of
  2621. the GNU MPFR library, which in turn refer to those of the GMP library.
  2622. Thus, when installing MPC, the MPFR and GMP libraries also get installed
  2623. in the profile; removing MPC also removes MPFR and GMP---unless they had
  2624. also been explicitly installed by the user.
  2625. Besides, packages sometimes rely on the definition of environment
  2626. variables for their search paths (see explanation of
  2627. @option{--search-paths} below). Any missing or possibly incorrect
  2628. environment variable definitions are reported here.
  2629. @item --install-from-expression=@var{exp}
  2630. @itemx -e @var{exp}
  2631. Install the package @var{exp} evaluates to.
  2632. @var{exp} must be a Scheme expression that evaluates to a
  2633. @code{<package>} object. This option is notably useful to disambiguate
  2634. between same-named variants of a package, with expressions such as
  2635. @code{(@@ (gnu packages base) guile-final)}.
  2636. Note that this option installs the first output of the specified
  2637. package, which may be insufficient when needing a specific output of a
  2638. multiple-output package.
  2639. @item --install-from-file=@var{file}
  2640. @itemx -f @var{file}
  2641. Install the package that the code within @var{file} evaluates to.
  2642. As an example, @var{file} might contain a definition like this
  2643. (@pxref{Defining Packages}):
  2644. @lisp
  2645. @include package-hello.scm
  2646. @end lisp
  2647. Developers may find it useful to include such a @file{guix.scm} file
  2648. in the root of their project source tree that can be used to test
  2649. development snapshots and create reproducible development environments
  2650. (@pxref{Invoking guix shell}).
  2651. The @var{file} may also contain a JSON representation of one or more
  2652. package definitions. Running @code{guix package -f} on
  2653. @file{hello.json} with the following contents would result in installing
  2654. the package @code{greeter} after building @code{myhello}:
  2655. @example
  2656. @verbatiminclude package-hello.json
  2657. @end example
  2658. @item --remove=@var{package} @dots{}
  2659. @itemx -r @var{package} @dots{}
  2660. Remove the specified @var{package}s.
  2661. As for @option{--install}, each @var{package} may specify a version number
  2662. and/or output name in addition to the package name. For instance,
  2663. @samp{-r glibc:debug} would remove the @code{debug} output of
  2664. @code{glibc}.
  2665. @item --upgrade[=@var{regexp} @dots{}]
  2666. @itemx -u [@var{regexp} @dots{}]
  2667. @cindex upgrading packages
  2668. Upgrade all the installed packages. If one or more @var{regexp}s are
  2669. specified, upgrade only installed packages whose name matches a
  2670. @var{regexp}. Also see the @option{--do-not-upgrade} option below.
  2671. Note that this upgrades package to the latest version of packages found
  2672. in the distribution currently installed. To update your distribution,
  2673. you should regularly run @command{guix pull} (@pxref{Invoking guix
  2674. pull}).
  2675. @cindex package transformations, upgrades
  2676. When upgrading, package transformations that were originally applied
  2677. when creating the profile are automatically re-applied (@pxref{Package
  2678. Transformation Options}). For example, assume you first installed Emacs
  2679. from the tip of its development branch with:
  2680. @example
  2681. guix install emacs-next --with-branch=emacs-next=master
  2682. @end example
  2683. Next time you run @command{guix upgrade}, Guix will again pull the tip
  2684. of the Emacs development branch and build @code{emacs-next} from that
  2685. checkout.
  2686. Note that transformation options such as @option{--with-branch} and
  2687. @option{--with-source} depend on external state; it is up to you to
  2688. ensure that they work as expected. You can also discard a
  2689. transformations that apply to a package by running:
  2690. @example
  2691. guix install @var{package}
  2692. @end example
  2693. @item --do-not-upgrade[=@var{regexp} @dots{}]
  2694. When used together with the @option{--upgrade} option, do @emph{not}
  2695. upgrade any packages whose name matches a @var{regexp}. For example, to
  2696. upgrade all packages in the current profile except those containing the
  2697. substring ``emacs'':
  2698. @example
  2699. $ guix package --upgrade . --do-not-upgrade emacs
  2700. @end example
  2701. @item @anchor{profile-manifest}--manifest=@var{file}
  2702. @itemx -m @var{file}
  2703. @cindex profile declaration
  2704. @cindex profile manifest
  2705. Create a new generation of the profile from the manifest object
  2706. returned by the Scheme code in @var{file}. This option can be repeated
  2707. several times, in which case the manifests are concatenated.
  2708. This allows you to @emph{declare} the profile's contents rather than
  2709. constructing it through a sequence of @option{--install} and similar
  2710. commands. The advantage is that @var{file} can be put under version
  2711. control, copied to different machines to reproduce the same profile, and
  2712. so on.
  2713. @c FIXME: Add reference to (guix profile) documentation when available.
  2714. @var{file} must return a @dfn{manifest} object, which is roughly a list
  2715. of packages:
  2716. @findex packages->manifest
  2717. @lisp
  2718. (use-package-modules guile emacs)
  2719. (packages->manifest
  2720. (list emacs
  2721. guile-2.0
  2722. ;; Use a specific package output.
  2723. (list guile-2.0 "debug")))
  2724. @end lisp
  2725. @findex specifications->manifest
  2726. In this example we have to know which modules define the @code{emacs}
  2727. and @code{guile-2.0} variables to provide the right
  2728. @code{use-package-modules} line, which can be cumbersome. We can
  2729. instead provide regular package specifications and let
  2730. @code{specifications->manifest} look up the corresponding package
  2731. objects, like this:
  2732. @lisp
  2733. (specifications->manifest
  2734. '("emacs" "guile@@2.2" "guile@@2.2:debug"))
  2735. @end lisp
  2736. @findex package->development-manifest
  2737. You might also want to create a manifest for all the dependencies of a
  2738. package, rather than the package itself:
  2739. @lisp
  2740. (package->development-manifest (specification->package "emacs"))
  2741. @end lisp
  2742. The example above gives you all the software required to develop Emacs,
  2743. similar to what @command{guix environment emacs} provides.
  2744. @xref{export-manifest, @option{--export-manifest}}, to learn how to
  2745. obtain a manifest file from an existing profile.
  2746. @item --roll-back
  2747. @cindex rolling back
  2748. @cindex undoing transactions
  2749. @cindex transactions, undoing
  2750. Roll back to the previous @dfn{generation} of the profile---i.e., undo
  2751. the last transaction.
  2752. When combined with options such as @option{--install}, roll back occurs
  2753. before any other actions.
  2754. When rolling back from the first generation that actually contains
  2755. installed packages, the profile is made to point to the @dfn{zeroth
  2756. generation}, which contains no files apart from its own metadata.
  2757. After having rolled back, installing, removing, or upgrading packages
  2758. overwrites previous future generations. Thus, the history of the
  2759. generations in a profile is always linear.
  2760. @item --switch-generation=@var{pattern}
  2761. @itemx -S @var{pattern}
  2762. @cindex generations
  2763. Switch to a particular generation defined by @var{pattern}.
  2764. @var{pattern} may be either a generation number or a number prefixed
  2765. with ``+'' or ``-''. The latter means: move forward/backward by a
  2766. specified number of generations. For example, if you want to return to
  2767. the latest generation after @option{--roll-back}, use
  2768. @option{--switch-generation=+1}.
  2769. The difference between @option{--roll-back} and
  2770. @option{--switch-generation=-1} is that @option{--switch-generation} will
  2771. not make a zeroth generation, so if a specified generation does not
  2772. exist, the current generation will not be changed.
  2773. @item --search-paths[=@var{kind}]
  2774. @cindex search paths
  2775. Report environment variable definitions, in Bash syntax, that may be
  2776. needed in order to use the set of installed packages. These environment
  2777. variables are used to specify @dfn{search paths} for files used by some
  2778. of the installed packages.
  2779. For example, GCC needs the @env{CPATH} and @env{LIBRARY_PATH}
  2780. environment variables to be defined so it can look for headers and
  2781. libraries in the user's profile (@pxref{Environment Variables,,, gcc,
  2782. Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
  2783. library are installed in the profile, then @option{--search-paths} will
  2784. suggest setting these variables to @file{@var{profile}/include} and
  2785. @file{@var{profile}/lib}, respectively (@pxref{Search Paths}, for info
  2786. on search path specifications associated with packages.)
  2787. The typical use case is to define these environment variables in the
  2788. shell:
  2789. @example
  2790. $ eval `guix package --search-paths`
  2791. @end example
  2792. @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
  2793. meaning that the returned environment variable definitions will either
  2794. be exact settings, or prefixes or suffixes of the current value of these
  2795. variables. When omitted, @var{kind} defaults to @code{exact}.
  2796. This option can also be used to compute the @emph{combined} search paths
  2797. of several profiles. Consider this example:
  2798. @example
  2799. $ guix package -p foo -i guile
  2800. $ guix package -p bar -i guile-json
  2801. $ guix package -p foo -p bar --search-paths
  2802. @end example
  2803. The last command above reports about the @env{GUILE_LOAD_PATH}
  2804. variable, even though, taken individually, neither @file{foo} nor
  2805. @file{bar} would lead to that recommendation.
  2806. @cindex profile, choosing
  2807. @item --profile=@var{profile}
  2808. @itemx -p @var{profile}
  2809. Use @var{profile} instead of the user's default profile.
  2810. @var{profile} must be the name of a file that will be created upon
  2811. completion. Concretely, @var{profile} will be a mere symbolic link
  2812. (``symlink'') pointing to the actual profile where packages are
  2813. installed:
  2814. @example
  2815. $ guix install hello -p ~/code/my-profile
  2816. @dots{}
  2817. $ ~/code/my-profile/bin/hello
  2818. Hello, world!
  2819. @end example
  2820. All it takes to get rid of the profile is to remove this symlink and its
  2821. siblings that point to specific generations:
  2822. @example
  2823. $ rm ~/code/my-profile ~/code/my-profile-*-link
  2824. @end example
  2825. @item --list-profiles
  2826. List all the user's profiles:
  2827. @example
  2828. $ guix package --list-profiles
  2829. /home/charlie/.guix-profile
  2830. /home/charlie/code/my-profile
  2831. /home/charlie/code/devel-profile
  2832. /home/charlie/tmp/test
  2833. @end example
  2834. When running as root, list all the profiles of all the users.
  2835. @cindex collisions, in a profile
  2836. @cindex colliding packages in profiles
  2837. @cindex profile collisions
  2838. @item --allow-collisions
  2839. Allow colliding packages in the new profile. Use at your own risk!
  2840. By default, @command{guix package} reports as an error @dfn{collisions}
  2841. in the profile. Collisions happen when two or more different versions
  2842. or variants of a given package end up in the profile.
  2843. @item --bootstrap
  2844. Use the bootstrap Guile to build the profile. This option is only
  2845. useful to distribution developers.
  2846. @end table
  2847. In addition to these actions, @command{guix package} supports the
  2848. following options to query the current state of a profile, or the
  2849. availability of packages:
  2850. @table @option
  2851. @item --search=@var{regexp}
  2852. @itemx -s @var{regexp}
  2853. @anchor{guix-search}
  2854. @cindex searching for packages
  2855. List the available packages whose name, synopsis, or description matches
  2856. @var{regexp} (in a case-insensitive fashion), sorted by relevance.
  2857. Print all the metadata of matching packages in
  2858. @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
  2859. GNU recutils manual}).
  2860. This allows specific fields to be extracted using the @command{recsel}
  2861. command, for instance:
  2862. @example
  2863. $ guix package -s malloc | recsel -p name,version,relevance
  2864. name: jemalloc
  2865. version: 4.5.0
  2866. relevance: 6
  2867. name: glibc
  2868. version: 2.25
  2869. relevance: 1
  2870. name: libgc
  2871. version: 7.6.0
  2872. relevance: 1
  2873. @end example
  2874. Similarly, to show the name of all the packages available under the
  2875. terms of the GNU@tie{}LGPL version 3:
  2876. @example
  2877. $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
  2878. name: elfutils
  2879. name: gmp
  2880. @dots{}
  2881. @end example
  2882. It is also possible to refine search results using several @code{-s} flags to
  2883. @command{guix package}, or several arguments to @command{guix search}. For
  2884. example, the following command returns a list of board games (this time using
  2885. the @command{guix search} alias):
  2886. @example
  2887. $ guix search '\<board\>' game | recsel -p name
  2888. name: gnubg
  2889. @dots{}
  2890. @end example
  2891. If we were to omit @code{-s game}, we would also get software packages
  2892. that deal with printed circuit boards; removing the angle brackets
  2893. around @code{board} would further add packages that have to do with
  2894. keyboards.
  2895. And now for a more elaborate example. The following command searches
  2896. for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
  2897. libraries, and prints the name and synopsis of the matching packages:
  2898. @example
  2899. $ guix search crypto library | \
  2900. recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
  2901. @end example
  2902. @noindent
  2903. @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
  2904. information on @dfn{selection expressions} for @code{recsel -e}.
  2905. @item --show=@var{package}
  2906. Show details about @var{package}, taken from the list of available packages, in
  2907. @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
  2908. recutils manual}).
  2909. @example
  2910. $ guix package --show=guile | recsel -p name,version
  2911. name: guile
  2912. version: 3.0.5
  2913. name: guile
  2914. version: 3.0.2
  2915. name: guile
  2916. version: 2.2.7
  2917. @dots{}
  2918. @end example
  2919. You may also specify the full name of a package to only get details about a
  2920. specific version of it (this time using the @command{guix show} alias):
  2921. @example
  2922. $ guix show guile@@3.0.5 | recsel -p name,version
  2923. name: guile
  2924. version: 3.0.5
  2925. @end example
  2926. @item --list-installed[=@var{regexp}]
  2927. @itemx -I [@var{regexp}]
  2928. List the currently installed packages in the specified profile, with the
  2929. most recently installed packages shown last. When @var{regexp} is
  2930. specified, list only installed packages whose name matches @var{regexp}.
  2931. For each installed package, print the following items, separated by
  2932. tabs: the package name, its version string, the part of the package that
  2933. is installed (for instance, @code{out} for the default output,
  2934. @code{include} for its headers, etc.), and the path of this package in
  2935. the store.
  2936. @item --list-available[=@var{regexp}]
  2937. @itemx -A [@var{regexp}]
  2938. List packages currently available in the distribution for this system
  2939. (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
  2940. available packages whose name matches @var{regexp}.
  2941. For each package, print the following items separated by tabs: its name,
  2942. its version string, the parts of the package (@pxref{Packages with
  2943. Multiple Outputs}), and the source location of its definition.
  2944. @item --list-generations[=@var{pattern}]
  2945. @itemx -l [@var{pattern}]
  2946. @cindex generations
  2947. Return a list of generations along with their creation dates; for each
  2948. generation, show the installed packages, with the most recently
  2949. installed packages shown last. Note that the zeroth generation is never
  2950. shown.
  2951. For each installed package, print the following items, separated by
  2952. tabs: the name of a package, its version string, the part of the package
  2953. that is installed (@pxref{Packages with Multiple Outputs}), and the
  2954. location of this package in the store.
  2955. When @var{pattern} is used, the command returns only matching
  2956. generations. Valid patterns include:
  2957. @itemize
  2958. @item @emph{Integers and comma-separated integers}. Both patterns denote
  2959. generation numbers. For instance, @option{--list-generations=1} returns
  2960. the first one.
  2961. And @option{--list-generations=1,8,2} outputs three generations in the
  2962. specified order. Neither spaces nor trailing commas are allowed.
  2963. @item @emph{Ranges}. @option{--list-generations=2..9} prints the
  2964. specified generations and everything in between. Note that the start of
  2965. a range must be smaller than its end.
  2966. It is also possible to omit the endpoint. For example,
  2967. @option{--list-generations=2..}, returns all generations starting from the
  2968. second one.
  2969. @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
  2970. or months by passing an integer along with the first letter of the
  2971. duration. For example, @option{--list-generations=20d} lists generations
  2972. that are up to 20 days old.
  2973. @end itemize
  2974. @item --delete-generations[=@var{pattern}]
  2975. @itemx -d [@var{pattern}]
  2976. When @var{pattern} is omitted, delete all generations except the current
  2977. one.
  2978. This command accepts the same patterns as @option{--list-generations}.
  2979. When @var{pattern} is specified, delete the matching generations. When
  2980. @var{pattern} specifies a duration, generations @emph{older} than the
  2981. specified duration match. For instance, @option{--delete-generations=1m}
  2982. deletes generations that are more than one month old.
  2983. If the current generation matches, it is @emph{not} deleted. Also, the
  2984. zeroth generation is never deleted.
  2985. Note that deleting generations prevents rolling back to them.
  2986. Consequently, this command must be used with care.
  2987. @cindex manifest, exporting
  2988. @anchor{export-manifest}
  2989. @item --export-manifest
  2990. Write to standard output a manifest suitable for @option{--manifest}
  2991. corresponding to the chosen profile(s).
  2992. This option is meant to help you migrate from the ``imperative''
  2993. operating mode---running @command{guix install}, @command{guix upgrade},
  2994. etc.---to the declarative mode that @option{--manifest} offers.
  2995. Be aware that the resulting manifest @emph{approximates} what your
  2996. profile actually contains; for instance, depending on how your profile
  2997. was created, it can refer to packages or package versions that are not
  2998. exactly what you specified.
  2999. Keep in mind that a manifest is purely symbolic: it only contains
  3000. package names and possibly versions, and their meaning varies over time.
  3001. If you wish to ``pin'' channels to the revisions that were used to build
  3002. the profile(s), see @option{--export-channels} below.
  3003. @cindex pinning, channel revisions of a profile
  3004. @item --export-channels
  3005. Write to standard output the list of channels used by the chosen
  3006. profile(s), in a format suitable for @command{guix pull --channels} or
  3007. @command{guix time-machine --channels} (@pxref{Channels}).
  3008. Together with @option{--export-manifest}, this option provides
  3009. information allowing you to replicate the current profile
  3010. (@pxref{Replicating Guix}).
  3011. However, note that the output of this command @emph{approximates} what
  3012. was actually used to build this profile. In particular, a single
  3013. profile might have been built from several different revisions of the
  3014. same channel. In that case, @option{--export-manifest} chooses the last
  3015. one and writes the list of other revisions in a comment. If you really
  3016. need to pick packages from different channel revisions, you can use
  3017. inferiors in your manifest to do so (@pxref{Inferiors}).
  3018. Together with @option{--export-manifest}, this is a good starting point
  3019. if you are willing to migrate from the ``imperative'' model to the fully
  3020. declarative model consisting of a manifest file along with a channels
  3021. file pinning the exact channel revision(s) you want.
  3022. @end table
  3023. Finally, since @command{guix package} may actually start build
  3024. processes, it supports all the common build options (@pxref{Common Build
  3025. Options}). It also supports package transformation options, such as
  3026. @option{--with-source}, and preserves them across upgrades
  3027. (@pxref{Package Transformation Options}).
  3028. @node Substitutes
  3029. @section Substitutes
  3030. @cindex substitutes
  3031. @cindex pre-built binaries
  3032. Guix supports transparent source/binary deployment, which means that it
  3033. can either build things locally, or download pre-built items from a
  3034. server, or both. We call these pre-built items @dfn{substitutes}---they
  3035. are substitutes for local build results. In many cases, downloading a
  3036. substitute is much faster than building things locally.
  3037. Substitutes can be anything resulting from a derivation build
  3038. (@pxref{Derivations}). Of course, in the common case, they are
  3039. pre-built package binaries, but source tarballs, for instance, which
  3040. also result from derivation builds, can be available as substitutes.
  3041. @menu
  3042. * Official Substitute Servers:: One particular source of substitutes.
  3043. * Substitute Server Authorization:: How to enable or disable substitutes.
  3044. * Getting Substitutes from Other Servers:: Substitute diversity.
  3045. * Substitute Authentication:: How Guix verifies substitutes.
  3046. * Proxy Settings:: How to get substitutes via proxy.
  3047. * Substitution Failure:: What happens when substitution fails.
  3048. * On Trusting Binaries:: How can you trust that binary blob?
  3049. @end menu
  3050. @node Official Substitute Servers
  3051. @subsection Official Substitute Servers
  3052. @cindex build farm
  3053. @code{@value{SUBSTITUTE-SERVER-1}} and
  3054. @code{@value{SUBSTITUTE-SERVER-2}} are both front-ends to official build
  3055. farms that build packages from Guix continuously for some architectures,
  3056. and make them available as substitutes. These are the default source of
  3057. substitutes; which can be overridden by passing the
  3058. @option{--substitute-urls} option either to @command{guix-daemon}
  3059. (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
  3060. or to client tools such as @command{guix package}
  3061. (@pxref{client-substitute-urls,, client @option{--substitute-urls}
  3062. option}).
  3063. Substitute URLs can be either HTTP or HTTPS.
  3064. HTTPS is recommended because communications are encrypted; conversely,
  3065. using HTTP makes all communications visible to an eavesdropper, who
  3066. could use the information gathered to determine, for instance, whether
  3067. your system has unpatched security vulnerabilities.
  3068. Substitutes from the official build farms are enabled by default when
  3069. using Guix System (@pxref{GNU Distribution}). However,
  3070. they are disabled by default when using Guix on a foreign distribution,
  3071. unless you have explicitly enabled them via one of the recommended
  3072. installation steps (@pxref{Installation}). The following paragraphs
  3073. describe how to enable or disable substitutes for the official build
  3074. farm; the same procedure can also be used to enable substitutes for any
  3075. other substitute server.
  3076. @node Substitute Server Authorization
  3077. @subsection Substitute Server Authorization
  3078. @cindex security
  3079. @cindex substitutes, authorization thereof
  3080. @cindex access control list (ACL), for substitutes
  3081. @cindex ACL (access control list), for substitutes
  3082. To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER-1}}, @code{@value{SUBSTITUTE-SERVER-2}} or a mirror, you
  3083. must add the relevant public key to the access control list (ACL) of archive
  3084. imports, using the @command{guix archive} command (@pxref{Invoking guix
  3085. archive}). Doing so implies that you trust the substitute server to not
  3086. be compromised and to serve genuine substitutes.
  3087. @quotation Note
  3088. If you are using Guix System, you can skip this section: Guix System
  3089. authorizes substitutes from @code{@value{SUBSTITUTE-SERVER-1}} and
  3090. @code{@value{SUBSTITUTE-SERVER-2}} by default.
  3091. @end quotation
  3092. The public keys for each of the project maintained substitute servers
  3093. are installed along with Guix, in @code{@var{prefix}/share/guix/}, where
  3094. @var{prefix} is the installation prefix of Guix. If you installed Guix
  3095. from source, make sure you checked the GPG signature of
  3096. @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
  3097. Then, you can run something like this:
  3098. @example
  3099. # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER-1}.pub
  3100. # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER-2}.pub
  3101. @end example
  3102. Once this is in place, the output of a command like @code{guix build}
  3103. should change from something like:
  3104. @example
  3105. $ guix build emacs --dry-run
  3106. The following derivations would be built:
  3107. /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
  3108. /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
  3109. /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
  3110. /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
  3111. @dots{}
  3112. @end example
  3113. @noindent
  3114. to something like:
  3115. @example
  3116. $ guix build emacs --dry-run
  3117. 112.3 MB would be downloaded:
  3118. /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
  3119. /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
  3120. /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
  3121. /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
  3122. @dots{}
  3123. @end example
  3124. @noindent
  3125. The text changed from ``The following derivations would be built'' to
  3126. ``112.3 MB would be downloaded''. This indicates that substitutes from
  3127. the configured substitute servers are usable and will be downloaded,
  3128. when possible, for future builds.
  3129. @cindex substitutes, how to disable
  3130. The substitute mechanism can be disabled globally by running
  3131. @code{guix-daemon} with @option{--no-substitutes} (@pxref{Invoking
  3132. guix-daemon}). It can also be disabled temporarily by passing the
  3133. @option{--no-substitutes} option to @command{guix package},
  3134. @command{guix build}, and other command-line tools.
  3135. @node Getting Substitutes from Other Servers
  3136. @subsection Getting Substitutes from Other Servers
  3137. @cindex substitute servers, adding more
  3138. Guix can look up and fetch substitutes from several servers. This is
  3139. useful when you are using packages from additional channels for which
  3140. the official server does not have substitutes but another server
  3141. provides them. Another situation where this is useful is when you would
  3142. prefer to download from your organization's substitute server, resorting
  3143. to the official server only as a fallback or dismissing it altogether.
  3144. You can give Guix a list of substitute server URLs and it will check
  3145. them in the specified order. You also need to explicitly authorize the
  3146. public keys of substitute servers to instruct Guix to accept the
  3147. substitutes they sign.
  3148. On Guix System, this is achieved by modifying the configuration of the
  3149. @code{guix} service. Since the @code{guix} service is part of the
  3150. default lists of services, @code{%base-services} and
  3151. @code{%desktop-services}, you can use @code{modify-services} to change
  3152. its configuration and add the URLs and substitute keys that you want
  3153. (@pxref{Service Reference, @code{modify-services}}).
  3154. As an example, suppose you want to fetch substitutes from
  3155. @code{guix.example.org} and to authorize the signing key of that server,
  3156. in addition to the default @code{@value{SUBSTITUTE-SERVER-1}} and
  3157. @code{@value{SUBSTITUTE-SERVER-2}}. The resulting operating system
  3158. configuration will look something like:
  3159. @lisp
  3160. (operating-system
  3161. ;; @dots{}
  3162. (services
  3163. ;; Assume we're starting from '%desktop-services'. Replace it
  3164. ;; with the list of services you're actually using.
  3165. (modify-services %desktop-services
  3166. (guix-service-type config =>
  3167. (guix-configuration
  3168. (inherit config)
  3169. (substitute-urls
  3170. (append (list "https://guix.example.org")
  3171. %default-substitute-urls))
  3172. (authorized-keys
  3173. (append (list (local-file "./key.pub"))
  3174. %default-authorized-guix-keys)))))))
  3175. @end lisp
  3176. This assumes that the file @file{key.pub} contains the signing key of
  3177. @code{guix.example.org}. With this change in place in your operating
  3178. system configuration file (say @file{/etc/config.scm}), you can
  3179. reconfigure and restart the @code{guix-daemon} service or reboot so the
  3180. changes take effect:
  3181. @example
  3182. $ sudo guix system reconfigure /etc/config.scm
  3183. $ sudo herd restart guix-daemon
  3184. @end example
  3185. If you're running Guix on a ``foreign distro'', you would instead take
  3186. the following steps to get substitutes from additional servers:
  3187. @enumerate
  3188. @item
  3189. Edit the service configuration file for @code{guix-daemon}; when using
  3190. systemd, this is normally
  3191. @file{/etc/systemd/system/guix-daemon.service}. Add the
  3192. @option{--substitute-urls} option on the @command{guix-daemon} command
  3193. line and list the URLs of interest (@pxref{daemon-substitute-urls,
  3194. @code{guix-daemon --substitute-urls}}):
  3195. @example
  3196. @dots{} --substitute-urls='https://guix.example.org @value{SUBSTITUTE-URLS}'
  3197. @end example
  3198. @item
  3199. Restart the daemon. For systemd, it goes like this:
  3200. @example
  3201. systemctl daemon-reload
  3202. systemctl restart guix-daemon.service
  3203. @end example
  3204. @item
  3205. Authorize the key of the new server (@pxref{Invoking guix archive}):
  3206. @example
  3207. guix archive --authorize < key.pub
  3208. @end example
  3209. Again this assumes @file{key.pub} contains the public key that
  3210. @code{guix.example.org} uses to sign substitutes.
  3211. @end enumerate
  3212. Now you're all set! Substitutes will be preferably taken from
  3213. @code{https://guix.example.org}, using
  3214. @code{@value{SUBSTITUTE-SERVER-1}} then
  3215. @code{@value{SUBSTITUTE-SERVER-2}} as fallback options. Of course you
  3216. can list as many substitute servers as you like, with the caveat that
  3217. substitute lookup can be slowed down if too many servers need to be
  3218. contacted.
  3219. Note that there are also situations where one may want to add the URL of
  3220. a substitute server @emph{without} authorizing its key.
  3221. @xref{Substitute Authentication}, to understand this fine point.
  3222. @node Substitute Authentication
  3223. @subsection Substitute Authentication
  3224. @cindex digital signatures
  3225. Guix detects and raises an error when attempting to use a substitute
  3226. that has been tampered with. Likewise, it ignores substitutes that are
  3227. not signed, or that are not signed by one of the keys listed in the ACL.
  3228. There is one exception though: if an unauthorized server provides
  3229. substitutes that are @emph{bit-for-bit identical} to those provided by
  3230. an authorized server, then the unauthorized server becomes eligible for
  3231. downloads. For example, assume we have chosen two substitute servers
  3232. with this option:
  3233. @example
  3234. --substitute-urls="https://a.example.org https://b.example.org"
  3235. @end example
  3236. @noindent
  3237. @cindex reproducible builds
  3238. If the ACL contains only the key for @samp{b.example.org}, and if
  3239. @samp{a.example.org} happens to serve the @emph{exact same} substitutes,
  3240. then Guix will download substitutes from @samp{a.example.org} because it
  3241. comes first in the list and can be considered a mirror of
  3242. @samp{b.example.org}. In practice, independent build machines usually
  3243. produce the same binaries, thanks to bit-reproducible builds (see
  3244. below).
  3245. When using HTTPS, the server's X.509 certificate is @emph{not} validated
  3246. (in other words, the server is not authenticated), contrary to what
  3247. HTTPS clients such as Web browsers usually do. This is because Guix
  3248. authenticates substitute information itself, as explained above, which
  3249. is what we care about (whereas X.509 certificates are about
  3250. authenticating bindings between domain names and public keys).
  3251. @node Proxy Settings
  3252. @subsection Proxy Settings
  3253. @vindex http_proxy
  3254. @vindex https_proxy
  3255. Substitutes are downloaded over HTTP or HTTPS@. The @env{http_proxy} and
  3256. @env{https_proxy} environment variables can be set in the environment of
  3257. @command{guix-daemon} and are honored for downloads of substitutes.
  3258. Note that the value of those environment variables in the environment
  3259. where @command{guix build}, @command{guix package}, and other client
  3260. commands are run has @emph{absolutely no effect}.
  3261. @node Substitution Failure
  3262. @subsection Substitution Failure
  3263. Even when a substitute for a derivation is available, sometimes the
  3264. substitution attempt will fail. This can happen for a variety of
  3265. reasons: the substitute server might be offline, the substitute may
  3266. recently have been deleted, the connection might have been interrupted,
  3267. etc.
  3268. When substitutes are enabled and a substitute for a derivation is
  3269. available, but the substitution attempt fails, Guix will attempt to
  3270. build the derivation locally depending on whether or not
  3271. @option{--fallback} was given (@pxref{fallback-option,, common build
  3272. option @option{--fallback}}). Specifically, if @option{--fallback} was
  3273. omitted, then no local build will be performed, and the derivation is
  3274. considered to have failed. However, if @option{--fallback} was given,
  3275. then Guix will attempt to build the derivation locally, and the success
  3276. or failure of the derivation depends on the success or failure of the
  3277. local build. Note that when substitutes are disabled or no substitute
  3278. is available for the derivation in question, a local build will
  3279. @emph{always} be performed, regardless of whether or not
  3280. @option{--fallback} was given.
  3281. To get an idea of how many substitutes are available right now, you can
  3282. try running the @command{guix weather} command (@pxref{Invoking guix
  3283. weather}). This command provides statistics on the substitutes provided
  3284. by a server.
  3285. @node On Trusting Binaries
  3286. @subsection On Trusting Binaries
  3287. @cindex trust, of pre-built binaries
  3288. Today, each individual's control over their own computing is at the
  3289. mercy of institutions, corporations, and groups with enough power and
  3290. determination to subvert the computing infrastructure and exploit its
  3291. weaknesses. While using substitutes can be convenient, we encourage
  3292. users to also build on their own, or even run their own build farm, such
  3293. that the project run substitute servers are less of an interesting
  3294. target. One way to help is by publishing the software you build using
  3295. @command{guix publish} so that others have one more choice of server to
  3296. download substitutes from (@pxref{Invoking guix publish}).
  3297. Guix has the foundations to maximize build reproducibility
  3298. (@pxref{Features}). In most cases, independent builds of a given
  3299. package or derivation should yield bit-identical results. Thus, through
  3300. a diverse set of independent package builds, we can strengthen the
  3301. integrity of our systems. The @command{guix challenge} command aims to
  3302. help users assess substitute servers, and to assist developers in
  3303. finding out about non-deterministic package builds (@pxref{Invoking guix
  3304. challenge}). Similarly, the @option{--check} option of @command{guix
  3305. build} allows users to check whether previously-installed substitutes
  3306. are genuine by rebuilding them locally (@pxref{build-check,
  3307. @command{guix build --check}}).
  3308. In the future, we want Guix to have support to publish and retrieve
  3309. binaries to/from other users, in a peer-to-peer fashion. If you would
  3310. like to discuss this project, join us on @email{guix-devel@@gnu.org}.
  3311. @node Packages with Multiple Outputs
  3312. @section Packages with Multiple Outputs
  3313. @cindex multiple-output packages
  3314. @cindex package outputs
  3315. @cindex outputs
  3316. Often, packages defined in Guix have a single @dfn{output}---i.e., the
  3317. source package leads to exactly one directory in the store. When running
  3318. @command{guix install glibc}, one installs the default output of the
  3319. GNU libc package; the default output is called @code{out}, but its name
  3320. can be omitted as shown in this command. In this particular case, the
  3321. default output of @code{glibc} contains all the C header files, shared
  3322. libraries, static libraries, Info documentation, and other supporting
  3323. files.
  3324. Sometimes it is more appropriate to separate the various types of files
  3325. produced from a single source package into separate outputs. For
  3326. instance, the GLib C library (used by GTK+ and related packages)
  3327. installs more than 20 MiB of reference documentation as HTML pages.
  3328. To save space for users who do not need it, the documentation goes to a
  3329. separate output, called @code{doc}. To install the main GLib output,
  3330. which contains everything but the documentation, one would run:
  3331. @example
  3332. guix install glib
  3333. @end example
  3334. @cindex documentation
  3335. The command to install its documentation is:
  3336. @example
  3337. guix install glib:doc
  3338. @end example
  3339. Some packages install programs with different ``dependency footprints''.
  3340. For instance, the WordNet package installs both command-line tools and
  3341. graphical user interfaces (GUIs). The former depend solely on the C
  3342. library, whereas the latter depend on Tcl/Tk and the underlying X
  3343. libraries. In this case, we leave the command-line tools in the default
  3344. output, whereas the GUIs are in a separate output. This allows users
  3345. who do not need the GUIs to save space. The @command{guix size} command
  3346. can help find out about such situations (@pxref{Invoking guix size}).
  3347. @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
  3348. There are several such multiple-output packages in the GNU distribution.
  3349. Other conventional output names include @code{lib} for libraries and
  3350. possibly header files, @code{bin} for stand-alone programs, and
  3351. @code{debug} for debugging information (@pxref{Installing Debugging
  3352. Files}). The outputs of a packages are listed in the third column of
  3353. the output of @command{guix package --list-available} (@pxref{Invoking
  3354. guix package}).
  3355. @node Invoking guix gc
  3356. @section Invoking @command{guix gc}
  3357. @cindex garbage collector
  3358. @cindex disk space
  3359. Packages that are installed, but not used, may be @dfn{garbage-collected}.
  3360. The @command{guix gc} command allows users to explicitly run the garbage
  3361. collector to reclaim space from the @file{/gnu/store} directory. It is
  3362. the @emph{only} way to remove files from @file{/gnu/store}---removing
  3363. files or directories manually may break it beyond repair!
  3364. @cindex GC roots
  3365. @cindex garbage collector roots
  3366. The garbage collector has a set of known @dfn{roots}: any file under
  3367. @file{/gnu/store} reachable from a root is considered @dfn{live} and
  3368. cannot be deleted; any other file is considered @dfn{dead} and may be
  3369. deleted. The set of garbage collector roots (``GC roots'' for short)
  3370. includes default user profiles; by default, the symlinks under
  3371. @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
  3372. added with @command{guix build --root}, for example (@pxref{Invoking
  3373. guix build}). The @command{guix gc --list-roots} command lists them.
  3374. Prior to running @code{guix gc --collect-garbage} to make space, it is
  3375. often useful to remove old generations from user profiles; that way, old
  3376. package builds referenced by those generations can be reclaimed. This
  3377. is achieved by running @code{guix package --delete-generations}
  3378. (@pxref{Invoking guix package}).
  3379. Our recommendation is to run a garbage collection periodically, or when
  3380. you are short on disk space. For instance, to guarantee that at least
  3381. 5@tie{}GB are available on your disk, simply run:
  3382. @example
  3383. guix gc -F 5G
  3384. @end example
  3385. It is perfectly safe to run as a non-interactive periodic job
  3386. (@pxref{Scheduled Job Execution}, for how to set up such a job).
  3387. Running @command{guix gc} with no arguments will collect as
  3388. much garbage as it can, but that is often inconvenient: you may find
  3389. yourself having to rebuild or re-download software that is ``dead'' from
  3390. the GC viewpoint but that is necessary to build other pieces of
  3391. software---e.g., the compiler tool chain.
  3392. The @command{guix gc} command has three modes of operation: it can be
  3393. used to garbage-collect any dead files (the default), to delete specific
  3394. files (the @option{--delete} option), to print garbage-collector
  3395. information, or for more advanced queries. The garbage collection
  3396. options are as follows:
  3397. @table @code
  3398. @item --collect-garbage[=@var{min}]
  3399. @itemx -C [@var{min}]
  3400. Collect garbage---i.e., unreachable @file{/gnu/store} files and
  3401. sub-directories. This is the default operation when no option is
  3402. specified.
  3403. When @var{min} is given, stop once @var{min} bytes have been collected.
  3404. @var{min} may be a number of bytes, or it may include a unit as a
  3405. suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
  3406. (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
  3407. When @var{min} is omitted, collect all the garbage.
  3408. @item --free-space=@var{free}
  3409. @itemx -F @var{free}
  3410. Collect garbage until @var{free} space is available under
  3411. @file{/gnu/store}, if possible; @var{free} denotes storage space, such
  3412. as @code{500MiB}, as described above.
  3413. When @var{free} or more is already available in @file{/gnu/store}, do
  3414. nothing and exit immediately.
  3415. @item --delete-generations[=@var{duration}]
  3416. @itemx -d [@var{duration}]
  3417. Before starting the garbage collection process, delete all the generations
  3418. older than @var{duration}, for all the user profiles; when run as root, this
  3419. applies to all the profiles @emph{of all the users}.
  3420. For example, this command deletes all the generations of all your profiles
  3421. that are older than 2 months (except generations that are current), and then
  3422. proceeds to free space until at least 10 GiB are available:
  3423. @example
  3424. guix gc -d 2m -F 10G
  3425. @end example
  3426. @item --delete
  3427. @itemx -D
  3428. Attempt to delete all the store files and directories specified as
  3429. arguments. This fails if some of the files are not in the store, or if
  3430. they are still live.
  3431. @item --list-failures
  3432. List store items corresponding to cached build failures.
  3433. This prints nothing unless the daemon was started with
  3434. @option{--cache-failures} (@pxref{Invoking guix-daemon,
  3435. @option{--cache-failures}}).
  3436. @item --list-roots
  3437. List the GC roots owned by the user; when run as root, list @emph{all} the GC
  3438. roots.
  3439. @item --list-busy
  3440. List store items in use by currently running processes. These store
  3441. items are effectively considered GC roots: they cannot be deleted.
  3442. @item --clear-failures
  3443. Remove the specified store items from the failed-build cache.
  3444. Again, this option only makes sense when the daemon is started with
  3445. @option{--cache-failures}. Otherwise, it does nothing.
  3446. @item --list-dead
  3447. Show the list of dead files and directories still present in the
  3448. store---i.e., files and directories no longer reachable from any root.
  3449. @item --list-live
  3450. Show the list of live store files and directories.
  3451. @end table
  3452. In addition, the references among existing store files can be queried:
  3453. @table @code
  3454. @item --references
  3455. @itemx --referrers
  3456. @cindex package dependencies
  3457. List the references (respectively, the referrers) of store files given
  3458. as arguments.
  3459. @item --requisites
  3460. @itemx -R
  3461. @cindex closure
  3462. List the requisites of the store files passed as arguments. Requisites
  3463. include the store files themselves, their references, and the references
  3464. of these, recursively. In other words, the returned list is the
  3465. @dfn{transitive closure} of the store files.
  3466. @xref{Invoking guix size}, for a tool to profile the size of the closure
  3467. of an element. @xref{Invoking guix graph}, for a tool to visualize
  3468. the graph of references.
  3469. @item --derivers
  3470. @cindex derivation
  3471. Return the derivation(s) leading to the given store items
  3472. (@pxref{Derivations}).
  3473. For example, this command:
  3474. @example
  3475. guix gc --derivers $(guix package -I ^emacs$ | cut -f4)
  3476. @end example
  3477. @noindent
  3478. returns the @file{.drv} file(s) leading to the @code{emacs} package
  3479. installed in your profile.
  3480. Note that there may be zero matching @file{.drv} files, for instance
  3481. because these files have been garbage-collected. There can also be more
  3482. than one matching @file{.drv} due to fixed-output derivations.
  3483. @end table
  3484. Lastly, the following options allow you to check the integrity of the
  3485. store and to control disk usage.
  3486. @table @option
  3487. @item --verify[=@var{options}]
  3488. @cindex integrity, of the store
  3489. @cindex integrity checking
  3490. Verify the integrity of the store.
  3491. By default, make sure that all the store items marked as valid in the
  3492. database of the daemon actually exist in @file{/gnu/store}.
  3493. When provided, @var{options} must be a comma-separated list containing one
  3494. or more of @code{contents} and @code{repair}.
  3495. When passing @option{--verify=contents}, the daemon computes the
  3496. content hash of each store item and compares it against its hash in the
  3497. database. Hash mismatches are reported as data corruptions. Because it
  3498. traverses @emph{all the files in the store}, this command can take a
  3499. long time, especially on systems with a slow disk drive.
  3500. @cindex repairing the store
  3501. @cindex corruption, recovering from
  3502. Using @option{--verify=repair} or @option{--verify=contents,repair}
  3503. causes the daemon to try to repair corrupt store items by fetching
  3504. substitutes for them (@pxref{Substitutes}). Because repairing is not
  3505. atomic, and thus potentially dangerous, it is available only to the
  3506. system administrator. A lightweight alternative, when you know exactly
  3507. which items in the store are corrupt, is @command{guix build --repair}
  3508. (@pxref{Invoking guix build}).
  3509. @item --optimize
  3510. @cindex deduplication
  3511. Optimize the store by hard-linking identical files---this is
  3512. @dfn{deduplication}.
  3513. The daemon performs deduplication after each successful build or archive
  3514. import, unless it was started with @option{--disable-deduplication}
  3515. (@pxref{Invoking guix-daemon, @option{--disable-deduplication}}). Thus,
  3516. this option is primarily useful when the daemon was running with
  3517. @option{--disable-deduplication}.
  3518. @end table
  3519. @node Invoking guix pull
  3520. @section Invoking @command{guix pull}
  3521. @cindex upgrading Guix
  3522. @cindex updating Guix
  3523. @cindex @command{guix pull}
  3524. @cindex pull
  3525. @cindex security, @command{guix pull}
  3526. @cindex authenticity, of code obtained with @command{guix pull}
  3527. Packages are installed or upgraded to the latest version available in
  3528. the distribution currently available on your local machine. To update
  3529. that distribution, along with the Guix tools, you must run @command{guix
  3530. pull}: the command downloads the latest Guix source code and package
  3531. descriptions, and deploys it. Source code is downloaded from a
  3532. @uref{https://git-scm.com, Git} repository, by default the official
  3533. GNU@tie{}Guix repository, though this can be customized. @command{guix
  3534. pull} ensures that the code it downloads is @emph{authentic} by
  3535. verifying that commits are signed by Guix developers.
  3536. Specifically, @command{guix pull} downloads code from the @dfn{channels}
  3537. (@pxref{Channels}) specified by one of the followings, in this order:
  3538. @enumerate
  3539. @item
  3540. the @option{--channels} option;
  3541. @item
  3542. the user's @file{~/.config/guix/channels.scm} file;
  3543. @item
  3544. the system-wide @file{/etc/guix/channels.scm} file;
  3545. @item
  3546. the built-in default channels specified in the @code{%default-channels}
  3547. variable.
  3548. @end enumerate
  3549. On completion, @command{guix package} will use packages and package
  3550. versions from this just-retrieved copy of Guix. Not only that, but all
  3551. the Guix commands and Scheme modules will also be taken from that latest
  3552. version. New @command{guix} sub-commands added by the update also
  3553. become available.
  3554. Any user can update their Guix copy using @command{guix pull}, and the
  3555. effect is limited to the user who ran @command{guix pull}. For
  3556. instance, when user @code{root} runs @command{guix pull}, this has no
  3557. effect on the version of Guix that user @code{alice} sees, and vice
  3558. versa.
  3559. The result of running @command{guix pull} is a @dfn{profile} available
  3560. under @file{~/.config/guix/current} containing the latest Guix. Thus,
  3561. make sure to add it to the beginning of your search path so that you use
  3562. the latest version, and similarly for the Info manual
  3563. (@pxref{Documentation}):
  3564. @example
  3565. export PATH="$HOME/.config/guix/current/bin:$PATH"
  3566. export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
  3567. @end example
  3568. The @option{--list-generations} or @option{-l} option lists past generations
  3569. produced by @command{guix pull}, along with details about their provenance:
  3570. @example
  3571. $ guix pull -l
  3572. Generation 1 Jun 10 2018 00:18:18
  3573. guix 65956ad
  3574. repository URL: https://git.savannah.gnu.org/git/guix.git
  3575. branch: origin/master
  3576. commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
  3577. Generation 2 Jun 11 2018 11:02:49
  3578. guix e0cc7f6
  3579. repository URL: https://git.savannah.gnu.org/git/guix.git
  3580. branch: origin/master
  3581. commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
  3582. Generation 3 Jun 13 2018 23:31:07 (current)
  3583. guix 844cc1c
  3584. repository URL: https://git.savannah.gnu.org/git/guix.git
  3585. branch: origin/master
  3586. commit: 844cc1c8f394f03b404c5bb3aee086922373490c
  3587. @end example
  3588. @xref{Invoking guix describe, @command{guix describe}}, for other ways to
  3589. describe the current status of Guix.
  3590. This @code{~/.config/guix/current} profile works exactly like the profiles
  3591. created by @command{guix package} (@pxref{Invoking guix package}). That
  3592. is, you can list generations, roll back to the previous
  3593. generation---i.e., the previous Guix---and so on:
  3594. @example
  3595. $ guix pull --roll-back
  3596. switched from generation 3 to 2
  3597. $ guix pull --delete-generations=1
  3598. deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
  3599. @end example
  3600. You can also use @command{guix package} (@pxref{Invoking guix package})
  3601. to manage the profile by naming it explicitly:
  3602. @example
  3603. $ guix package -p ~/.config/guix/current --roll-back
  3604. switched from generation 3 to 2
  3605. $ guix package -p ~/.config/guix/current --delete-generations=1
  3606. deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
  3607. @end example
  3608. The @command{guix pull} command is usually invoked with no arguments,
  3609. but it supports the following options:
  3610. @table @code
  3611. @item --url=@var{url}
  3612. @itemx --commit=@var{commit}
  3613. @itemx --branch=@var{branch}
  3614. Download code for the @code{guix} channel from the specified @var{url}, at the
  3615. given @var{commit} (a valid Git commit ID represented as a hexadecimal
  3616. string), or @var{branch}.
  3617. @cindex @file{channels.scm}, configuration file
  3618. @cindex configuration file for channels
  3619. These options are provided for convenience, but you can also specify your
  3620. configuration in the @file{~/.config/guix/channels.scm} file or using the
  3621. @option{--channels} option (see below).
  3622. @item --channels=@var{file}
  3623. @itemx -C @var{file}
  3624. Read the list of channels from @var{file} instead of
  3625. @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
  3626. @var{file} must contain Scheme code that
  3627. evaluates to a list of channel objects. @xref{Channels}, for more
  3628. information.
  3629. @cindex channel news
  3630. @item --news
  3631. @itemx -N
  3632. Display news written by channel authors for their users for changes made
  3633. since the previous generation (@pxref{Channels, Writing Channel News}).
  3634. When @option{--details} is passed, additionally display new and upgraded
  3635. packages.
  3636. You can view that information for previous generations with
  3637. @command{guix pull -l}.
  3638. @item --list-generations[=@var{pattern}]
  3639. @itemx -l [@var{pattern}]
  3640. List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
  3641. is provided, the subset of generations that match @var{pattern}.
  3642. The syntax of @var{pattern} is the same as with @code{guix package
  3643. --list-generations} (@pxref{Invoking guix package}).
  3644. By default, this prints information about the channels used in each
  3645. revision as well as the corresponding news entries. If you pass
  3646. @option{--details}, it will also print the list of packages added and
  3647. upgraded in each generation compared to the previous one.
  3648. @item --details
  3649. Instruct @option{--list-generations} or @option{--news} to display more
  3650. information about the differences between subsequent generations---see
  3651. above.
  3652. @item --roll-back
  3653. @cindex rolling back
  3654. @cindex undoing transactions
  3655. @cindex transactions, undoing
  3656. Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
  3657. undo the last transaction.
  3658. @item --switch-generation=@var{pattern}
  3659. @itemx -S @var{pattern}
  3660. @cindex generations
  3661. Switch to a particular generation defined by @var{pattern}.
  3662. @var{pattern} may be either a generation number or a number prefixed
  3663. with ``+'' or ``-''. The latter means: move forward/backward by a
  3664. specified number of generations. For example, if you want to return to
  3665. the latest generation after @option{--roll-back}, use
  3666. @option{--switch-generation=+1}.
  3667. @item --delete-generations[=@var{pattern}]
  3668. @itemx -d [@var{pattern}]
  3669. When @var{pattern} is omitted, delete all generations except the current
  3670. one.
  3671. This command accepts the same patterns as @option{--list-generations}.
  3672. When @var{pattern} is specified, delete the matching generations. When
  3673. @var{pattern} specifies a duration, generations @emph{older} than the
  3674. specified duration match. For instance, @option{--delete-generations=1m}
  3675. deletes generations that are more than one month old.
  3676. If the current generation matches, it is @emph{not} deleted.
  3677. Note that deleting generations prevents rolling back to them.
  3678. Consequently, this command must be used with care.
  3679. @xref{Invoking guix describe}, for a way to display information about the
  3680. current generation only.
  3681. @item --profile=@var{profile}
  3682. @itemx -p @var{profile}
  3683. Use @var{profile} instead of @file{~/.config/guix/current}.
  3684. @item --dry-run
  3685. @itemx -n
  3686. Show which channel commit(s) would be used and what would be built or
  3687. substituted but do not actually do it.
  3688. @item --allow-downgrades
  3689. Allow pulling older or unrelated revisions of channels than those
  3690. currently in use.
  3691. @cindex downgrade attacks, protection against
  3692. By default, @command{guix pull} protects against so-called ``downgrade
  3693. attacks'' whereby the Git repository of a channel would be reset to an
  3694. earlier or unrelated revision of itself, potentially leading you to
  3695. install older, known-vulnerable versions of software packages.
  3696. @quotation Note
  3697. Make sure you understand its security implications before using
  3698. @option{--allow-downgrades}.
  3699. @end quotation
  3700. @item --disable-authentication
  3701. Allow pulling channel code without authenticating it.
  3702. @cindex authentication, of channel code
  3703. By default, @command{guix pull} authenticates code downloaded from
  3704. channels by verifying that its commits are signed by authorized
  3705. developers, and raises an error if this is not the case. This option
  3706. instructs it to not perform any such verification.
  3707. @quotation Note
  3708. Make sure you understand its security implications before using
  3709. @option{--disable-authentication}.
  3710. @end quotation
  3711. @item --system=@var{system}
  3712. @itemx -s @var{system}
  3713. Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
  3714. the system type of the build host.
  3715. @item --bootstrap
  3716. Use the bootstrap Guile to build the latest Guix. This option is only
  3717. useful to Guix developers.
  3718. @end table
  3719. The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
  3720. repository and branch to pull from, as well as @emph{additional} repositories
  3721. containing package modules that should be deployed. @xref{Channels}, for more
  3722. information.
  3723. In addition, @command{guix pull} supports all the common build options
  3724. (@pxref{Common Build Options}).
  3725. @node Invoking guix time-machine
  3726. @section Invoking @command{guix time-machine}
  3727. @cindex @command{guix time-machine}
  3728. @cindex pinning, channels
  3729. @cindex replicating Guix
  3730. @cindex reproducibility, of Guix
  3731. The @command{guix time-machine} command provides access to other
  3732. revisions of Guix, for example to install older versions of packages,
  3733. or to reproduce a computation in an identical environment. The revision
  3734. of Guix to be used is defined by a commit or by a channel
  3735. description file created by @command{guix describe}
  3736. (@pxref{Invoking guix describe}).
  3737. The general syntax is:
  3738. @example
  3739. guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
  3740. @end example
  3741. where @var{command} and @var{arg}@dots{} are passed unmodified to the
  3742. @command{guix} command of the specified revision. The @var{options} that define
  3743. this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
  3744. @table @code
  3745. @item --url=@var{url}
  3746. @itemx --commit=@var{commit}
  3747. @itemx --branch=@var{branch}
  3748. Use the @code{guix} channel from the specified @var{url}, at the
  3749. given @var{commit} (a valid Git commit ID represented as a hexadecimal
  3750. string), or @var{branch}.
  3751. @item --channels=@var{file}
  3752. @itemx -C @var{file}
  3753. Read the list of channels from @var{file}. @var{file} must contain
  3754. Scheme code that evaluates to a list of channel objects.
  3755. @xref{Channels} for more information.
  3756. @end table
  3757. As for @command{guix pull}, the absence of any options means that the
  3758. latest commit on the master branch will be used. The command
  3759. @example
  3760. guix time-machine -- build hello
  3761. @end example
  3762. will thus build the package @code{hello} as defined in the master branch,
  3763. which is in general a newer revision of Guix than you have installed.
  3764. Time travel works in both directions!
  3765. Note that @command{guix time-machine} can trigger builds of channels and
  3766. their dependencies, and these are controlled by the standard build
  3767. options (@pxref{Common Build Options}).
  3768. @node Inferiors
  3769. @section Inferiors
  3770. @c TODO: Remove this once we're more confident about API stability.
  3771. @quotation Note
  3772. The functionality described here is a ``technology preview'' as of version
  3773. @value{VERSION}. As such, the interface is subject to change.
  3774. @end quotation
  3775. @cindex inferiors
  3776. @cindex composition of Guix revisions
  3777. Sometimes you might need to mix packages from the revision of Guix you're
  3778. currently running with packages available in a different revision of Guix.
  3779. Guix @dfn{inferiors} allow you to achieve that by composing different Guix
  3780. revisions in arbitrary ways.
  3781. @cindex inferior packages
  3782. Technically, an ``inferior'' is essentially a separate Guix process connected
  3783. to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
  3784. @code{(guix inferior)} module allows you to create inferiors and to
  3785. communicate with them. It also provides a high-level interface to browse and
  3786. manipulate the packages that an inferior provides---@dfn{inferior packages}.
  3787. When combined with channels (@pxref{Channels}), inferiors provide a simple way
  3788. to interact with a separate revision of Guix. For example, let's assume you
  3789. want to install in your profile the current @code{guile} package, along with
  3790. the @code{guile-json} as it existed in an older revision of Guix---perhaps
  3791. because the newer @code{guile-json} has an incompatible API and you want to
  3792. run your code against the old API@. To do that, you could write a manifest for
  3793. use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
  3794. manifest, you would create an inferior for that old Guix revision you care
  3795. about, and you would look up the @code{guile-json} package in the inferior:
  3796. @lisp
  3797. (use-modules (guix inferior) (guix channels)
  3798. (srfi srfi-1)) ;for 'first'
  3799. (define channels
  3800. ;; This is the old revision from which we want to
  3801. ;; extract guile-json.
  3802. (list (channel
  3803. (name 'guix)
  3804. (url "https://git.savannah.gnu.org/git/guix.git")
  3805. (commit
  3806. "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
  3807. (define inferior
  3808. ;; An inferior representing the above revision.
  3809. (inferior-for-channels channels))
  3810. ;; Now create a manifest with the current "guile" package
  3811. ;; and the old "guile-json" package.
  3812. (packages->manifest
  3813. (list (first (lookup-inferior-packages inferior "guile-json"))
  3814. (specification->package "guile")))
  3815. @end lisp
  3816. On its first run, @command{guix package --manifest} might have to build the
  3817. channel you specified before it can create the inferior; subsequent runs will
  3818. be much faster because the Guix revision will be cached.
  3819. The @code{(guix inferior)} module provides the following procedures to open an
  3820. inferior:
  3821. @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
  3822. [#:cache-directory] [#:ttl]
  3823. Return an inferior for @var{channels}, a list of channels. Use the cache at
  3824. @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
  3825. This procedure opens a new connection to the build daemon.
  3826. As a side effect, this procedure may build or substitute binaries for
  3827. @var{channels}, which can take time.
  3828. @end deffn
  3829. @deffn {Scheme Procedure} open-inferior @var{directory} @
  3830. [#:command "bin/guix"]
  3831. Open the inferior Guix in @var{directory}, running
  3832. @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
  3833. the inferior could not be launched.
  3834. @end deffn
  3835. @cindex inferior packages
  3836. The procedures listed below allow you to obtain and manipulate inferior
  3837. packages.
  3838. @deffn {Scheme Procedure} inferior-packages @var{inferior}
  3839. Return the list of packages known to @var{inferior}.
  3840. @end deffn
  3841. @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
  3842. [@var{version}]
  3843. Return the sorted list of inferior packages matching @var{name} in
  3844. @var{inferior}, with highest version numbers first. If @var{version} is true,
  3845. return only packages with a version number prefixed by @var{version}.
  3846. @end deffn
  3847. @deffn {Scheme Procedure} inferior-package? @var{obj}
  3848. Return true if @var{obj} is an inferior package.
  3849. @end deffn
  3850. @deffn {Scheme Procedure} inferior-package-name @var{package}
  3851. @deffnx {Scheme Procedure} inferior-package-version @var{package}
  3852. @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
  3853. @deffnx {Scheme Procedure} inferior-package-description @var{package}
  3854. @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
  3855. @deffnx {Scheme Procedure} inferior-package-location @var{package}
  3856. @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
  3857. @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
  3858. @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
  3859. @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
  3860. @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
  3861. @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
  3862. @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
  3863. These procedures are the counterpart of package record accessors
  3864. (@pxref{package Reference}). Most of them work by querying the inferior
  3865. @var{package} comes from, so the inferior must still be live when you call
  3866. these procedures.
  3867. @end deffn
  3868. Inferior packages can be used transparently like any other package or
  3869. file-like object in G-expressions (@pxref{G-Expressions}). They are also
  3870. transparently handled by the @code{packages->manifest} procedure, which is
  3871. commonly used in manifests (@pxref{Invoking guix package, the
  3872. @option{--manifest} option of @command{guix package}}). Thus you can insert
  3873. an inferior package pretty much anywhere you would insert a regular package:
  3874. in manifests, in the @code{packages} field of your @code{operating-system}
  3875. declaration, and so on.
  3876. @node Invoking guix describe
  3877. @section Invoking @command{guix describe}
  3878. @cindex reproducibility
  3879. @cindex replicating Guix
  3880. Often you may want to answer questions like: ``Which revision of Guix am I
  3881. using?'' or ``Which channels am I using?'' This is useful information in many
  3882. situations: if you want to @emph{replicate} an environment on a different
  3883. machine or user account, if you want to report a bug or to determine what
  3884. change in the channels you are using caused it, or if you want to record your
  3885. system state for reproducibility purposes. The @command{guix describe}
  3886. command answers these questions.
  3887. When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
  3888. displays the channel(s) that it was built from, including their repository URL
  3889. and commit IDs (@pxref{Channels}):
  3890. @example
  3891. $ guix describe
  3892. Generation 10 Sep 03 2018 17:32:44 (current)
  3893. guix e0fa68c
  3894. repository URL: https://git.savannah.gnu.org/git/guix.git
  3895. branch: master
  3896. commit: e0fa68c7718fffd33d81af415279d6ddb518f727
  3897. @end example
  3898. If you're familiar with the Git version control system, this is similar in
  3899. spirit to @command{git describe}; the output is also similar to that of
  3900. @command{guix pull --list-generations}, but limited to the current generation
  3901. (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
  3902. the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
  3903. information is all it takes to describe the revision of Guix you're using, and
  3904. also to replicate it.
  3905. To make it easier to replicate Guix, @command{guix describe} can also be asked
  3906. to return a list of channels instead of the human-readable description above:
  3907. @example
  3908. $ guix describe -f channels
  3909. (list (channel
  3910. (name 'guix)
  3911. (url "https://git.savannah.gnu.org/git/guix.git")
  3912. (commit
  3913. "e0fa68c7718fffd33d81af415279d6ddb518f727")
  3914. (introduction
  3915. (make-channel-introduction
  3916. "9edb3f66fd807b096b48283debdcddccfea34bad"
  3917. (openpgp-fingerprint
  3918. "BBB0 2DDF 2CEA F6A8 0D1D E643 A2A0 6DF2 A33A 54FA")))))
  3919. @end example
  3920. @noindent
  3921. You can save this to a file and feed it to @command{guix pull -C} on some
  3922. other machine or at a later point in time, which will instantiate @emph{this
  3923. exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
  3924. From there on, since you're able to deploy the same revision of Guix, you can
  3925. just as well @emph{replicate a complete software environment}. We humbly
  3926. think that this is @emph{awesome}, and we hope you'll like it too!
  3927. The details of the options supported by @command{guix describe} are as
  3928. follows:
  3929. @table @code
  3930. @item --format=@var{format}
  3931. @itemx -f @var{format}
  3932. Produce output in the specified @var{format}, one of:
  3933. @table @code
  3934. @item human
  3935. produce human-readable output;
  3936. @item channels
  3937. produce a list of channel specifications that can be passed to @command{guix
  3938. pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
  3939. guix pull});
  3940. @item channels-sans-intro
  3941. like @code{channels}, but omit the @code{introduction} field; use it to
  3942. produce a channel specification suitable for Guix version 1.1.0 or
  3943. earlier---the @code{introduction} field has to do with channel
  3944. authentication (@pxref{Channels, Channel Authentication}) and is not
  3945. supported by these older versions;
  3946. @item json
  3947. @cindex JSON
  3948. produce a list of channel specifications in JSON format;
  3949. @item recutils
  3950. produce a list of channel specifications in Recutils format.
  3951. @end table
  3952. @item --list-formats
  3953. Display available formats for @option{--format} option.
  3954. @item --profile=@var{profile}
  3955. @itemx -p @var{profile}
  3956. Display information about @var{profile}.
  3957. @end table
  3958. @node Invoking guix archive
  3959. @section Invoking @command{guix archive}
  3960. @cindex @command{guix archive}
  3961. @cindex archive
  3962. The @command{guix archive} command allows users to @dfn{export} files
  3963. from the store into a single archive, and to later @dfn{import} them on
  3964. a machine that runs Guix.
  3965. In particular, it allows store files to be transferred from one machine
  3966. to the store on another machine.
  3967. @quotation Note
  3968. If you're looking for a way to produce archives in a format suitable for
  3969. tools other than Guix, @pxref{Invoking guix pack}.
  3970. @end quotation
  3971. @cindex exporting store items
  3972. To export store files as an archive to standard output, run:
  3973. @example
  3974. guix archive --export @var{options} @var{specifications}...
  3975. @end example
  3976. @var{specifications} may be either store file names or package
  3977. specifications, as for @command{guix package} (@pxref{Invoking guix
  3978. package}). For instance, the following command creates an archive
  3979. containing the @code{gui} output of the @code{git} package and the main
  3980. output of @code{emacs}:
  3981. @example
  3982. guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
  3983. @end example
  3984. If the specified packages are not built yet, @command{guix archive}
  3985. automatically builds them. The build process may be controlled with the
  3986. common build options (@pxref{Common Build Options}).
  3987. To transfer the @code{emacs} package to a machine connected over SSH,
  3988. one would run:
  3989. @example
  3990. guix archive --export -r emacs | ssh the-machine guix archive --import
  3991. @end example
  3992. @noindent
  3993. Similarly, a complete user profile may be transferred from one machine
  3994. to another like this:
  3995. @example
  3996. guix archive --export -r $(readlink -f ~/.guix-profile) | \
  3997. ssh the-machine guix archive --import
  3998. @end example
  3999. @noindent
  4000. However, note that, in both examples, all of @code{emacs} and the
  4001. profile as well as all of their dependencies are transferred (due to
  4002. @option{-r}), regardless of what is already available in the store on
  4003. the target machine. The @option{--missing} option can help figure out
  4004. which items are missing from the target store. The @command{guix copy}
  4005. command simplifies and optimizes this whole process, so this is probably
  4006. what you should use in this case (@pxref{Invoking guix copy}).
  4007. @cindex nar, archive format
  4008. @cindex normalized archive (nar)
  4009. @cindex nar bundle, archive format
  4010. Each store item is written in the @dfn{normalized archive} or @dfn{nar}
  4011. format (described below), and the output of @command{guix archive
  4012. --export} (and input of @command{guix archive --import}) is a @dfn{nar
  4013. bundle}.
  4014. The nar format is
  4015. comparable in spirit to `tar', but with differences
  4016. that make it more appropriate for our purposes. First, rather than
  4017. recording all Unix metadata for each file, the nar format only mentions
  4018. the file type (regular, directory, or symbolic link); Unix permissions
  4019. and owner/group are dismissed. Second, the order in which directory
  4020. entries are stored always follows the order of file names according to
  4021. the C locale collation order. This makes archive production fully
  4022. deterministic.
  4023. That nar bundle format is essentially the concatenation of zero or more
  4024. nars along with metadata for each store item it contains: its file name,
  4025. references, corresponding derivation, and a digital signature.
  4026. When exporting, the daemon digitally signs the contents of the archive,
  4027. and that digital signature is appended. When importing, the daemon
  4028. verifies the signature and rejects the import in case of an invalid
  4029. signature or if the signing key is not authorized.
  4030. @c FIXME: Add xref to daemon doc about signatures.
  4031. The main options are:
  4032. @table @code
  4033. @item --export
  4034. Export the specified store files or packages (see below). Write the
  4035. resulting archive to the standard output.
  4036. Dependencies are @emph{not} included in the output, unless
  4037. @option{--recursive} is passed.
  4038. @item -r
  4039. @itemx --recursive
  4040. When combined with @option{--export}, this instructs @command{guix archive}
  4041. to include dependencies of the given items in the archive. Thus, the
  4042. resulting archive is self-contained: it contains the closure of the
  4043. exported store items.
  4044. @item --import
  4045. Read an archive from the standard input, and import the files listed
  4046. therein into the store. Abort if the archive has an invalid digital
  4047. signature, or if it is signed by a public key not among the authorized
  4048. keys (see @option{--authorize} below).
  4049. @item --missing
  4050. Read a list of store file names from the standard input, one per line,
  4051. and write on the standard output the subset of these files missing from
  4052. the store.
  4053. @item --generate-key[=@var{parameters}]
  4054. @cindex signing, archives
  4055. Generate a new key pair for the daemon. This is a prerequisite before
  4056. archives can be exported with @option{--export}. This
  4057. operation is usually instantaneous but it can take time if the system's
  4058. entropy pool needs to be refilled. On Guix System,
  4059. @code{guix-service-type} takes care of generating this key pair the
  4060. first boot.
  4061. The generated key pair is typically stored under @file{/etc/guix}, in
  4062. @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
  4063. key, which must be kept secret). When @var{parameters} is omitted,
  4064. an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
  4065. versions before 1.6.0, it is a 4096-bit RSA key.
  4066. Alternatively, @var{parameters} can specify
  4067. @code{genkey} parameters suitable for Libgcrypt (@pxref{General
  4068. public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
  4069. Libgcrypt Reference Manual}).
  4070. @item --authorize
  4071. @cindex authorizing, archives
  4072. Authorize imports signed by the public key passed on standard input.
  4073. The public key must be in ``s-expression advanced format''---i.e., the
  4074. same format as the @file{signing-key.pub} file.
  4075. The list of authorized keys is kept in the human-editable file
  4076. @file{/etc/guix/acl}. The file contains
  4077. @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
  4078. s-expressions''} and is structured as an access-control list in the
  4079. @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
  4080. (SPKI)}.
  4081. @item --extract=@var{directory}
  4082. @itemx -x @var{directory}
  4083. Read a single-item archive as served by substitute servers
  4084. (@pxref{Substitutes}) and extract it to @var{directory}. This is a
  4085. low-level operation needed in only very narrow use cases; see below.
  4086. For example, the following command extracts the substitute for Emacs
  4087. served by @code{@value{SUBSTITUTE-SERVER-1}} to @file{/tmp/emacs}:
  4088. @example
  4089. $ wget -O - \
  4090. https://@value{SUBSTITUTE-SERVER-1}/nar/gzip/@dots{}-emacs-24.5 \
  4091. | gunzip | guix archive -x /tmp/emacs
  4092. @end example
  4093. Single-item archives are different from multiple-item archives produced
  4094. by @command{guix archive --export}; they contain a single store item,
  4095. and they do @emph{not} embed a signature. Thus this operation does
  4096. @emph{no} signature verification and its output should be considered
  4097. unsafe.
  4098. The primary purpose of this operation is to facilitate inspection of
  4099. archive contents coming from possibly untrusted substitute servers
  4100. (@pxref{Invoking guix challenge}).
  4101. @item --list
  4102. @itemx -t
  4103. Read a single-item archive as served by substitute servers
  4104. (@pxref{Substitutes}) and print the list of files it contains, as in
  4105. this example:
  4106. @example
  4107. $ wget -O - \
  4108. https://@value{SUBSTITUTE-SERVER-1}/nar/lzip/@dots{}-emacs-26.3 \
  4109. | lzip -d | guix archive -t
  4110. @end example
  4111. @end table
  4112. @c *********************************************************************
  4113. @node Channels
  4114. @chapter Channels
  4115. @cindex channels
  4116. @cindex @file{channels.scm}, configuration file
  4117. @cindex configuration file for channels
  4118. @cindex @command{guix pull}, configuration file
  4119. @cindex configuration of @command{guix pull}
  4120. Guix and its package collection are updated by running @command{guix pull}
  4121. (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
  4122. deploys Guix itself from the official GNU@tie{}Guix repository. This can be
  4123. customized by defining @dfn{channels} in the
  4124. @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
  4125. of a Git repository to be deployed, and @command{guix pull} can be instructed
  4126. to pull from one or more channels. In other words, channels can be used
  4127. to @emph{customize} and to @emph{extend} Guix, as we will see below.
  4128. Guix is able to take into account security concerns and deal with authenticated
  4129. updates.
  4130. @menu
  4131. * Specifying Additional Channels:: Extending the package collection.
  4132. * Using a Custom Guix Channel:: Using a customized Guix.
  4133. * Replicating Guix:: Running the @emph{exact same} Guix.
  4134. * Channel Authentication:: How Guix verifies what it fetches.
  4135. * Channels with Substitutes:: Using channels with available substitutes.
  4136. * Creating a Channel:: How to write your custom channel.
  4137. * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
  4138. * Declaring Channel Dependencies:: How to depend on other channels.
  4139. * Specifying Channel Authorizations:: Defining channel authors authorizations.
  4140. * Primary URL:: Distinguishing mirror to original.
  4141. * Writing Channel News:: Communicating information to channel's users.
  4142. @end menu
  4143. @node Specifying Additional Channels
  4144. @section Specifying Additional Channels
  4145. @cindex extending the package collection (channels)
  4146. @cindex variant packages (channels)
  4147. You can specify @emph{additional channels} to pull from. To use a channel, write
  4148. @code{~/.config/guix/channels.scm} to instruct @command{guix pull} to pull from it
  4149. @emph{in addition} to the default Guix channel(s):
  4150. @vindex %default-channels
  4151. @lisp
  4152. ;; Add variant packages to those Guix provides.
  4153. (cons (channel
  4154. (name 'variant-packages)
  4155. (url "https://example.org/variant-packages.git"))
  4156. %default-channels)
  4157. @end lisp
  4158. @noindent
  4159. Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
  4160. add a channel the list of channels that the variable @code{%default-channels}
  4161. is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
  4162. Manual}). With this file in place, @command{guix pull} builds not only Guix
  4163. but also the package modules from your own repository. The result in
  4164. @file{~/.config/guix/current} is the union of Guix with your own package
  4165. modules:
  4166. @example
  4167. $ guix pull --list-generations
  4168. @dots{}
  4169. Generation 19 Aug 27 2018 16:20:48
  4170. guix d894ab8
  4171. repository URL: https://git.savannah.gnu.org/git/guix.git
  4172. branch: master
  4173. commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
  4174. variant-packages dd3df5e
  4175. repository URL: https://example.org/variant-packages.git
  4176. branch: master
  4177. commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
  4178. 11 new packages: variant-gimp, variant-emacs-with-cool-features, @dots{}
  4179. 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
  4180. @end example
  4181. @noindent
  4182. The output of @command{guix pull} above shows that Generation@tie{}19 includes
  4183. both Guix and packages from the @code{variant-personal-packages} channel. Among
  4184. the new and upgraded packages that are listed, some like @code{variant-gimp} and
  4185. @code{variant-emacs-with-cool-features} might come from
  4186. @code{variant-packages}, while others come from the Guix default channel.
  4187. @node Using a Custom Guix Channel
  4188. @section Using a Custom Guix Channel
  4189. The channel called @code{guix} specifies where Guix itself---its command-line
  4190. tools as well as its package collection---should be downloaded. For instance,
  4191. suppose you want to update from another copy of the Guix repository at
  4192. @code{example.org}, and specifically the @code{super-hacks} branch, you can
  4193. write in @code{~/.config/guix/channels.scm} this specification:
  4194. @lisp
  4195. ;; Tell 'guix pull' to use another repo.
  4196. (list (channel
  4197. (name 'guix)
  4198. (url "https://example.org/another-guix.git")
  4199. (branch "super-hacks")))
  4200. @end lisp
  4201. @noindent
  4202. From there on, @command{guix pull} will fetch code from the @code{super-hacks}
  4203. branch of the repository at @code{example.org}. The authentication concern is
  4204. addressed below ((@pxref{Channel Authentication}).
  4205. @node Replicating Guix
  4206. @section Replicating Guix
  4207. @cindex pinning, channels
  4208. @cindex replicating Guix
  4209. @cindex reproducibility, of Guix
  4210. The @command{guix pull --list-generations} output above shows precisely which
  4211. commits were used to build this instance of Guix. We can thus replicate it,
  4212. say, on another machine, by providing a channel specification in
  4213. @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
  4214. @lisp
  4215. ;; Deploy specific commits of my channels of interest.
  4216. (list (channel
  4217. (name 'guix)
  4218. (url "https://git.savannah.gnu.org/git/guix.git")
  4219. (commit "6298c3ffd9654d3231a6f25390b056483e8f407c"))
  4220. (channel
  4221. (name 'variant-packages)
  4222. (url "https://example.org/variant-packages.git")
  4223. (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
  4224. @end lisp
  4225. The @command{guix describe --format=channels} command can even generate this
  4226. list of channels directly (@pxref{Invoking guix describe}). The resulting
  4227. file can be used with the -C options of @command{guix pull}
  4228. (@pxref{Invoking guix pull}) or @command{guix time-machine}
  4229. (@pxref{Invoking guix time-machine}).
  4230. At this point the two machines run the @emph{exact same Guix}, with access to
  4231. the @emph{exact same packages}. The output of @command{guix build gimp} on
  4232. one machine will be exactly the same, bit for bit, as the output of the same
  4233. command on the other machine. It also means both machines have access to all
  4234. the source code of Guix and, transitively, to all the source code of every
  4235. package it defines.
  4236. This gives you super powers, allowing you to track the provenance of binary
  4237. artifacts with very fine grain, and to reproduce software environments at
  4238. will---some sort of ``meta reproducibility'' capabilities, if you will.
  4239. @xref{Inferiors}, for another way to take advantage of these super powers.
  4240. @node Channel Authentication
  4241. @section Channel Authentication
  4242. @anchor{channel-authentication}
  4243. @cindex authentication, of channel code
  4244. The @command{guix pull} and @command{guix time-machine} commands
  4245. @dfn{authenticate} the code retrieved from channels: they make sure each
  4246. commit that is fetched is signed by an authorized developer. The goal
  4247. is to protect from unauthorized modifications to the channel that would
  4248. lead users to run malicious code.
  4249. As a user, you must provide a @dfn{channel introduction} in your
  4250. channels file so that Guix knows how to authenticate its first commit.
  4251. A channel specification, including its introduction, looks something
  4252. along these lines:
  4253. @lisp
  4254. (channel
  4255. (name 'some-channel)
  4256. (url "https://example.org/some-channel.git")
  4257. (introduction
  4258. (make-channel-introduction
  4259. "6f0d8cc0d88abb59c324b2990bfee2876016bb86"
  4260. (openpgp-fingerprint
  4261. "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
  4262. @end lisp
  4263. The specification above shows the name and URL of the channel. The call
  4264. to @code{make-channel-introduction} above specifies that authentication
  4265. of this channel starts at commit @code{6f0d8cc@dots{}}, which is signed
  4266. by the OpenPGP key with fingerprint @code{CABB A931@dots{}}.
  4267. For the main channel, called @code{guix}, you automatically get that
  4268. information from your Guix installation. For other channels, include
  4269. the channel introduction provided by the channel authors in your
  4270. @file{channels.scm} file. Make sure you retrieve the channel
  4271. introduction from a trusted source since that is the root of your trust.
  4272. If you're curious about the authentication mechanics, read on!
  4273. @node Channels with Substitutes
  4274. @section Channels with Substitutes
  4275. When running @command{guix pull}, Guix will first compile the
  4276. definitions of every available package. This is an expensive operation
  4277. for which substitutes (@pxref{Substitutes}) may be available. The
  4278. following snippet in @file{channels.scm} will ensure that @command{guix
  4279. pull} uses the latest commit with available substitutes for the package
  4280. definitions: this is done by querying the continuous integration
  4281. server at @url{https://ci.guix.gnu.org}.
  4282. @lisp
  4283. (use-modules (guix ci))
  4284. (list (channel-with-substitutes-available
  4285. %default-guix-channel
  4286. "https://ci.guix.gnu.org"))
  4287. @end lisp
  4288. Note that this does not mean that all the packages that you will
  4289. install after running @command{guix pull} will have available
  4290. substitutes. It only ensures that @command{guix pull} will not try to
  4291. compile package definitions. This is particularly useful when using
  4292. machines with limited resources.
  4293. @node Creating a Channel
  4294. @section Creating a Channel
  4295. @cindex personal packages (channels)
  4296. @cindex channels, for personal packages
  4297. Let's say you have a bunch of custom package variants or personal packages
  4298. that you think would make little sense to contribute to the Guix project, but
  4299. would like to have these packages transparently available to you at the
  4300. command line. You would first write modules containing those package
  4301. definitions (@pxref{Package Modules}), maintain them in a Git repository, and
  4302. then you and anyone else can use it as an additional channel to get packages
  4303. from. Neat, no?
  4304. @c What follows stems from discussions at
  4305. @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
  4306. @c earlier discussions on guix-devel@gnu.org.
  4307. @quotation Warning
  4308. Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
  4309. publish your personal channel to the world, we would like to share a few words
  4310. of caution:
  4311. @itemize
  4312. @item
  4313. Before publishing a channel, please consider contributing your package
  4314. definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
  4315. to free software of all sorts, and packages in Guix proper are readily
  4316. available to all Guix users and benefit from the project's quality assurance
  4317. process.
  4318. @item
  4319. When you maintain package definitions outside Guix, we, Guix developers,
  4320. consider that @emph{the compatibility burden is on you}. Remember that
  4321. package modules and package definitions are just Scheme code that uses various
  4322. programming interfaces (APIs). We want to remain free to change these APIs to
  4323. keep improving Guix, possibly in ways that break your channel. We never
  4324. change APIs gratuitously, but we will @emph{not} commit to freezing APIs
  4325. either.
  4326. @item
  4327. Corollary: if you're using an external channel and that channel breaks, please
  4328. @emph{report the issue to the channel authors}, not to the Guix project.
  4329. @end itemize
  4330. You've been warned! Having said this, we believe external channels are a
  4331. practical way to exert your freedom to augment Guix' package collection and to
  4332. share your improvements, which are basic tenets of
  4333. @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
  4334. email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
  4335. @end quotation
  4336. To create a channel, create a Git repository containing your own package
  4337. modules and make it available. The repository can contain anything, but a
  4338. useful channel will contain Guile modules that export packages. Once you
  4339. start using a channel, Guix will behave as if the root directory of that
  4340. channel's Git repository has been added to the Guile load path (@pxref{Load
  4341. Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
  4342. contains a file at @file{my-packages/my-tools.scm} that defines a Guile
  4343. module, then the module will be available under the name @code{(my-packages
  4344. my-tools)}, and you will be able to use it like any other module
  4345. (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
  4346. As a channel author, consider bundling authentication material with your
  4347. channel so that users can authenticate it. @xref{Channel
  4348. Authentication}, and @ref{Specifying Channel Authorizations}, for info
  4349. on how to do it.
  4350. @node Package Modules in a Sub-directory
  4351. @section Package Modules in a Sub-directory
  4352. @cindex subdirectory, channels
  4353. As a channel author, you may want to keep your channel modules in a
  4354. sub-directory. If your modules are in the sub-directory @file{guix}, you must
  4355. add a meta-data file @file{.guix-channel} that contains:
  4356. @lisp
  4357. (channel
  4358. (version 0)
  4359. (directory "guix"))
  4360. @end lisp
  4361. @node Declaring Channel Dependencies
  4362. @section Declaring Channel Dependencies
  4363. @cindex dependencies, channels
  4364. @cindex meta-data, channels
  4365. Channel authors may decide to augment a package collection provided by other
  4366. channels. They can declare their channel to be dependent on other channels in
  4367. a meta-data file @file{.guix-channel}, which is to be placed in the root of
  4368. the channel repository.
  4369. The meta-data file should contain a simple S-expression like this:
  4370. @lisp
  4371. (channel
  4372. (version 0)
  4373. (dependencies
  4374. (channel
  4375. (name some-collection)
  4376. (url "https://example.org/first-collection.git")
  4377. ;; The 'introduction' bit below is optional: you would
  4378. ;; provide it for dependencies that can be authenticated.
  4379. (introduction
  4380. (channel-introduction
  4381. (version 0)
  4382. (commit "a8883b58dc82e167c96506cf05095f37c2c2c6cd")
  4383. (signer "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
  4384. (channel
  4385. (name some-other-collection)
  4386. (url "https://example.org/second-collection.git")
  4387. (branch "testing"))))
  4388. @end lisp
  4389. In the above example this channel is declared to depend on two other channels,
  4390. which will both be fetched automatically. The modules provided by the channel
  4391. will be compiled in an environment where the modules of all these declared
  4392. channels are available.
  4393. For the sake of reliability and maintainability, you should avoid dependencies
  4394. on channels that you don't control, and you should aim to keep the number of
  4395. dependencies to a minimum.
  4396. @node Specifying Channel Authorizations
  4397. @section Specifying Channel Authorizations
  4398. @cindex channel authorizations
  4399. @anchor{channel-authorizations}
  4400. As we saw above, Guix ensures the source code it pulls from channels
  4401. comes from authorized developers. As a channel author, you need to
  4402. specify the list of authorized developers in the
  4403. @file{.guix-authorizations} file in the channel's Git repository. The
  4404. authentication rule is simple: each commit must be signed by a key
  4405. listed in the @file{.guix-authorizations} file of its parent
  4406. commit(s)@footnote{Git commits form a @dfn{directed acyclic graph}
  4407. (DAG). Each commit can have zero or more parents; ``regular'' commits
  4408. have one parent and merge commits have two parent commits. Read
  4409. @uref{https://eagain.net/articles/git-for-computer-scientists/, @i{Git
  4410. for Computer Scientists}} for a great overview.} The
  4411. @file{.guix-authorizations} file looks like this:
  4412. @lisp
  4413. ;; Example '.guix-authorizations' file.
  4414. (authorizations
  4415. (version 0) ;current file format version
  4416. (("AD17 A21E F8AE D8F1 CC02 DBD9 F8AE D8F1 765C 61E3"
  4417. (name "alice"))
  4418. ("2A39 3FFF 68F4 EF7A 3D29 12AF 68F4 EF7A 22FB B2D5"
  4419. (name "bob"))
  4420. ("CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"
  4421. (name "charlie"))))
  4422. @end lisp
  4423. Each fingerprint is followed by optional key/value pairs, as in the
  4424. example above. Currently these key/value pairs are ignored.
  4425. This authentication rule creates a chicken-and-egg issue: how do we
  4426. authenticate the first commit? Related to that: how do we deal with
  4427. channels whose repository history contains unsigned commits and lack
  4428. @file{.guix-authorizations}? And how do we fork existing channels?
  4429. @cindex channel introduction
  4430. Channel introductions answer these questions by describing the first
  4431. commit of a channel that should be authenticated. The first time a
  4432. channel is fetched with @command{guix pull} or @command{guix
  4433. time-machine}, the command looks up the introductory commit and verifies
  4434. that it is signed by the specified OpenPGP key. From then on, it
  4435. authenticates commits according to the rule above. Authentication fails
  4436. if the target commit is neither a descendant nor an ancestor of the
  4437. introductory commit.
  4438. Additionally, your channel must provide all the OpenPGP keys that were
  4439. ever mentioned in @file{.guix-authorizations}, stored as @file{.key}
  4440. files, which can be either binary or ``ASCII-armored''. By default,
  4441. those @file{.key} files are searched for in the branch named
  4442. @code{keyring} but you can specify a different branch name in
  4443. @code{.guix-channel} like so:
  4444. @lisp
  4445. (channel
  4446. (version 0)
  4447. (keyring-reference "my-keyring-branch"))
  4448. @end lisp
  4449. To summarize, as the author of a channel, there are three things you have
  4450. to do to allow users to authenticate your code:
  4451. @enumerate
  4452. @item
  4453. Export the OpenPGP keys of past and present committers with @command{gpg
  4454. --export} and store them in @file{.key} files, by default in a branch
  4455. named @code{keyring} (we recommend making it an @dfn{orphan branch}).
  4456. @item
  4457. Introduce an initial @file{.guix-authorizations} in the channel's
  4458. repository. Do that in a signed commit (@pxref{Commit Access}, for
  4459. information on how to sign Git commits.)
  4460. @item
  4461. Advertise the channel introduction, for instance on your channel's web
  4462. page. The channel introduction, as we saw above, is the commit/key
  4463. pair---i.e., the commit that introduced @file{.guix-authorizations}, and
  4464. the fingerprint of the OpenPGP used to sign it.
  4465. @end enumerate
  4466. Before pushing to your public Git repository, you can run @command{guix
  4467. git-authenticate} to verify that you did sign all the commits you are
  4468. about to push with an authorized key:
  4469. @example
  4470. guix git authenticate @var{commit} @var{signer}
  4471. @end example
  4472. @noindent
  4473. where @var{commit} and @var{signer} are your channel introduction.
  4474. @xref{Invoking guix git authenticate}, for details.
  4475. Publishing a signed channel requires discipline: any mistake, such as an
  4476. unsigned commit or a commit signed by an unauthorized key, will prevent
  4477. users from pulling from your channel---well, that's the whole point of
  4478. authentication! Pay attention to merges in particular: merge commits
  4479. are considered authentic if and only if they are signed by a key present
  4480. in the @file{.guix-authorizations} file of @emph{both} branches.
  4481. @node Primary URL
  4482. @section Primary URL
  4483. @cindex primary URL, channels
  4484. Channel authors can indicate the primary URL of their channel's Git
  4485. repository in the @file{.guix-channel} file, like so:
  4486. @lisp
  4487. (channel
  4488. (version 0)
  4489. (url "https://example.org/guix.git"))
  4490. @end lisp
  4491. This allows @command{guix pull} to determine whether it is pulling code
  4492. from a mirror of the channel; when that is the case, it warns the user
  4493. that the mirror might be stale and displays the primary URL@. That way,
  4494. users cannot be tricked into fetching code from a stale mirror that does
  4495. not receive security updates.
  4496. This feature only makes sense for authenticated repositories, such as
  4497. the official @code{guix} channel, for which @command{guix pull} ensures
  4498. the code it fetches is authentic.
  4499. @node Writing Channel News
  4500. @section Writing Channel News
  4501. @cindex news, for channels
  4502. Channel authors may occasionally want to communicate to their users
  4503. information about important changes in the channel. You'd send them all
  4504. an email, but that's not convenient.
  4505. Instead, channels can provide a @dfn{news file}; when the channel users
  4506. run @command{guix pull}, that news file is automatically read and
  4507. @command{guix pull --news} can display the announcements that correspond
  4508. to the new commits that have been pulled, if any.
  4509. To do that, channel authors must first declare the name of the news file
  4510. in their @file{.guix-channel} file:
  4511. @lisp
  4512. (channel
  4513. (version 0)
  4514. (news-file "etc/news.txt"))
  4515. @end lisp
  4516. The news file itself, @file{etc/news.txt} in this example, must look
  4517. something like this:
  4518. @lisp
  4519. (channel-news
  4520. (version 0)
  4521. (entry (tag "the-bug-fix")
  4522. (title (en "Fixed terrible bug")
  4523. (fr "Oh la la"))
  4524. (body (en "@@emph@{Good news@}! It's fixed!")
  4525. (eo "Certe ĝi pli bone funkcias nun!")))
  4526. (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
  4527. (title (en "Added a great package")
  4528. (ca "Què vol dir guix?"))
  4529. (body (en "Don't miss the @@code@{hello@} package!"))))
  4530. @end lisp
  4531. While the news file is using the Scheme syntax, avoid naming it with a
  4532. @file{.scm} extension or else it will get picked up when building the
  4533. channel and yield an error since it is not a valid module.
  4534. Alternatively, you can move the channel module to a subdirectory and
  4535. store the news file in another directory.
  4536. The file consists of a list of @dfn{news entries}. Each entry is
  4537. associated with a commit or tag: it describes changes made in this
  4538. commit, possibly in preceding commits as well. Users see entries only
  4539. the first time they obtain the commit the entry refers to.
  4540. The @code{title} field should be a one-line summary while @code{body}
  4541. can be arbitrarily long, and both can contain Texinfo markup
  4542. (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
  4543. a list of language tag/message tuples, which allows @command{guix pull}
  4544. to display news in the language that corresponds to the user's locale.
  4545. If you want to translate news using a gettext-based workflow, you can
  4546. extract translatable strings with @command{xgettext} (@pxref{xgettext
  4547. Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
  4548. you write news entries in English first, the command below creates a PO
  4549. file containing the strings to translate:
  4550. @example
  4551. xgettext -o news.po -l scheme -ken etc/news.txt
  4552. @end example
  4553. To sum up, yes, you could use your channel as a blog. But beware, this
  4554. is @emph{not quite} what your users might expect.
  4555. @c *********************************************************************
  4556. @node Development
  4557. @chapter Development
  4558. @cindex software development
  4559. If you are a software developer, Guix provides tools that you should find
  4560. helpful---independently of the language you're developing in. This is what
  4561. this chapter is about.
  4562. The @command{guix shell} command provides a convenient way to set up
  4563. one-off software environments, be it for development purposes or to run
  4564. a command without installing it in your profile. The @command{guix
  4565. pack} command allows you to create @dfn{application bundles} that can be
  4566. easily distributed to users who do not run Guix.
  4567. @menu
  4568. * Invoking guix shell:: Spawning one-off software environments.
  4569. * Invoking guix environment:: Setting up development environments.
  4570. * Invoking guix pack:: Creating software bundles.
  4571. * The GCC toolchain:: Working with languages supported by GCC.
  4572. * Invoking guix git authenticate:: Authenticating Git repositories.
  4573. @end menu
  4574. @node Invoking guix shell
  4575. @section Invoking @command{guix shell}
  4576. @cindex reproducible build environments
  4577. @cindex development environments
  4578. @cindex @command{guix environment}
  4579. @cindex environment, package build environment
  4580. The purpose of @command{guix shell} is to make it easy to create one-off
  4581. software environments, without changing one's profile. It is typically
  4582. used to create development environments; it is also a convenient way to
  4583. run applications without ``polluting'' your profile.
  4584. @quotation Note
  4585. The @command{guix shell} command was recently introduced to supersede
  4586. @command{guix environment} (@pxref{Invoking guix environment}). If you
  4587. are familiar with @command{guix environment}, you will notice that it is
  4588. similar but also---we hope!---more convenient.
  4589. @end quotation
  4590. The general syntax is:
  4591. @example
  4592. guix shell [@var{options}] [@var{package}@dots{}]
  4593. @end example
  4594. The following example creates an environment containing Python and NumPy,
  4595. building or downloading any missing package, and runs the
  4596. @command{python3} command in that environment:
  4597. @example
  4598. guix shell python python-numpy -- python3
  4599. @end example
  4600. Development environments can be created as in the example below, which
  4601. spawns an interactive shell containing all the dependencies and
  4602. environment variables needed to work on Inkscape:
  4603. @example
  4604. guix shell --development inkscape
  4605. @end example
  4606. Exiting the shell places the user back in the original environment
  4607. before @command{guix shell} was invoked. The next garbage collection
  4608. (@pxref{Invoking guix gc}) may clean up packages that were installed in
  4609. the environment and that are no longer used outside of it.
  4610. As an added convenience, when running from a directory that contains a
  4611. @file{manifest.scm} or a @file{guix.scm} file (in this order), possibly
  4612. in a parent directory, @command{guix shell} automatically loads the
  4613. file---provided the directory is listed in
  4614. @file{~/.config/guix/shell-authorized-directories}, and only for
  4615. interactive use:
  4616. @example
  4617. guix shell
  4618. @end example
  4619. This provides an easy way to define, share, and enter development
  4620. environments.
  4621. By default, the shell session or command runs in an @emph{augmented}
  4622. environment, where the new packages are added to search path environment
  4623. variables such as @code{PATH}. You can, instead, choose to create an
  4624. @emph{isolated} environment containing nothing but the packages you
  4625. asked for. Passing the @option{--pure} option clears environment
  4626. variable definitions found in the parent environment@footnote{Be sure to
  4627. use the @option{--check} option the first time you use @command{guix
  4628. shell} interactively to make sure the shell does not undo the effect of
  4629. @option{--pure}.}; passing @option{--container} goes one step further by
  4630. spawning a @dfn{container} isolated from the rest of the system:
  4631. @example
  4632. guix shell --container emacs gcc-toolchain
  4633. @end example
  4634. The command above spawns an interactive shell in a container where
  4635. nothing but @code{emacs}, @code{gcc-toolchain}, and their dependencies
  4636. is available. The container lacks network access and shares no files
  4637. other than the current working directory with the surrounding
  4638. environment. This is useful to prevent access to system-wide resources
  4639. such as @file{/usr/bin} on foreign distros.
  4640. This @option{--container} option can also prove useful if you wish to
  4641. run a security-sensitive application, such as a web browser, in an
  4642. isolated environment. For example, the command below launches
  4643. Ungoogled-Chromium in an isolated environment, this time sharing network
  4644. access with the host and preserving its @code{DISPLAY} environment
  4645. variable, but without even sharing the current directory:
  4646. @example
  4647. guix shell --container --network --no-cwd ungoogled-chromium \
  4648. --preserve='^DISPLAY$' -- chromium
  4649. @end example
  4650. @vindex GUIX_ENVIRONMENT
  4651. @command{guix shell} defines the @env{GUIX_ENVIRONMENT}
  4652. variable in the shell it spawns; its value is the file name of the
  4653. profile of this environment. This allows users to, say, define a
  4654. specific prompt for development environments in their @file{.bashrc}
  4655. (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
  4656. @example
  4657. if [ -n "$GUIX_ENVIRONMENT" ]
  4658. then
  4659. export PS1="\u@@\h \w [dev]\$ "
  4660. fi
  4661. @end example
  4662. @noindent
  4663. ...@: or to browse the profile:
  4664. @example
  4665. $ ls "$GUIX_ENVIRONMENT/bin"
  4666. @end example
  4667. The available options are summarized below.
  4668. @table @code
  4669. @item --check
  4670. Set up the environment and check whether the shell would clobber
  4671. environment variables. It's a good idea to use this option the first
  4672. time you run @command{guix shell} for an interactive session to make
  4673. sure your setup is correct.
  4674. For example, if the shell modifies the @env{PATH} environment variable,
  4675. report it since you would get a different environment than what you
  4676. asked for.
  4677. Such problems usually indicate that the shell startup files are
  4678. unexpectedly modifying those environment variables. For example, if you
  4679. are using Bash, make sure that environment variables are set or modified
  4680. in @file{~/.bash_profile} and @emph{not} in @file{~/.bashrc}---the
  4681. former is sourced only by log-in shells. @xref{Bash Startup Files,,,
  4682. bash, The GNU Bash Reference Manual}, for details on Bash start-up
  4683. files.
  4684. @item --development
  4685. @itemx -D
  4686. Cause @command{guix shell} to include in the environment the
  4687. dependencies of the following package rather than the package itself.
  4688. This can be combined with other packages. For instance, the command
  4689. below starts an interactive shell containing the build-time dependencies
  4690. of GNU@tie{}Guile, plus Autoconf, Automake, and Libtool:
  4691. @example
  4692. guix shell -D guile autoconf automake libtool
  4693. @end example
  4694. @item --expression=@var{expr}
  4695. @itemx -e @var{expr}
  4696. Create an environment for the package or list of packages that
  4697. @var{expr} evaluates to.
  4698. For example, running:
  4699. @example
  4700. guix shell -D -e '(@@ (gnu packages maths) petsc-openmpi)'
  4701. @end example
  4702. starts a shell with the environment for this specific variant of the
  4703. PETSc package.
  4704. Running:
  4705. @example
  4706. guix shell -e '(@@ (gnu) %base-packages)'
  4707. @end example
  4708. starts a shell with all the base system packages available.
  4709. The above commands only use the default output of the given packages.
  4710. To select other outputs, two element tuples can be specified:
  4711. @example
  4712. guix shell -e '(list (@@ (gnu packages bash) bash) "include")'
  4713. @end example
  4714. @item --file=@var{file}
  4715. @itemx -f @var{file}
  4716. Create an environment containing the package or list of packages that
  4717. the code within @var{file} evaluates to.
  4718. As an example, @var{file} might contain a definition like this
  4719. (@pxref{Defining Packages}):
  4720. @lisp
  4721. @verbatiminclude environment-gdb.scm
  4722. @end lisp
  4723. With the file above, you can enter a development environment for GDB by
  4724. running:
  4725. @example
  4726. guix shell -D -f gdb-devel.scm
  4727. @end example
  4728. @item --manifest=@var{file}
  4729. @itemx -m @var{file}
  4730. Create an environment for the packages contained in the manifest object
  4731. returned by the Scheme code in @var{file}. This option can be repeated
  4732. several times, in which case the manifests are concatenated.
  4733. This is similar to the same-named option in @command{guix package}
  4734. (@pxref{profile-manifest, @option{--manifest}}) and uses the same
  4735. manifest files.
  4736. See @option{--export-manifest} below on how to obtain a first manifest.
  4737. @cindex manifest, exporting
  4738. @anchor{shell-export-manifest}
  4739. @item --export-manifest
  4740. Write to standard output a manifest suitable for @option{--manifest}
  4741. corresponding to given command-line options.
  4742. This is a way to ``convert'' command-line arguments into a manifest.
  4743. For example, imagine you are tired of typing long lines and would like
  4744. to get a manifest equivalent to this command line:
  4745. @example
  4746. guix shell -D guile git emacs emacs-geiser emacs-geiser-guile
  4747. @end example
  4748. Just add @option{--export-manifest} to the command line above:
  4749. @example
  4750. guix shell --export-manifest \
  4751. -D guile git emacs emacs-geiser emacs-geiser-guile
  4752. @end example
  4753. @noindent
  4754. ... and you get a manifest along these lines:
  4755. @lisp
  4756. (concatenate-manifests
  4757. (list (specifications->manifest
  4758. (list "git"
  4759. "emacs"
  4760. "emacs-geiser"
  4761. "emacs-geiser-guile"))
  4762. (package->development-manifest
  4763. (specification->package "guile"))))
  4764. @end lisp
  4765. You can store it into a file, say @file{manifest.scm}, and from there
  4766. pass it to @command{guix shell} or indeed pretty much any @command{guix}
  4767. command:
  4768. @example
  4769. guix shell -m manifest.scm
  4770. @end example
  4771. Voilà, you've converted a long command line into a manifest! That
  4772. conversion process honors package transformation options (@pxref{Package
  4773. Transformation Options}) so it should be lossless.
  4774. @item --profile=@var{profile}
  4775. @itemx -p @var{profile}
  4776. Create an environment containing the packages installed in @var{profile}.
  4777. Use @command{guix package} (@pxref{Invoking guix package}) to create
  4778. and manage profiles.
  4779. @item --pure
  4780. Unset existing environment variables when building the new environment, except
  4781. those specified with @option{--preserve} (see below). This has the effect of
  4782. creating an environment in which search paths only contain package inputs.
  4783. @item --preserve=@var{regexp}
  4784. @itemx -E @var{regexp}
  4785. When used alongside @option{--pure}, preserve the environment variables
  4786. matching @var{regexp}---in other words, put them on a ``white list'' of
  4787. environment variables that must be preserved. This option can be repeated
  4788. several times.
  4789. @example
  4790. guix shell --pure --preserve=^SLURM openmpi @dots{} \
  4791. -- mpirun @dots{}
  4792. @end example
  4793. This example runs @command{mpirun} in a context where the only environment
  4794. variables defined are @env{PATH}, environment variables whose name starts
  4795. with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
  4796. @env{USER}, etc.).
  4797. @item --search-paths
  4798. Display the environment variable definitions that make up the
  4799. environment.
  4800. @item --system=@var{system}
  4801. @itemx -s @var{system}
  4802. Attempt to build for @var{system}---e.g., @code{i686-linux}.
  4803. @item --container
  4804. @itemx -C
  4805. @cindex container
  4806. Run @var{command} within an isolated container. The current working
  4807. directory outside the container is mapped inside the container.
  4808. Additionally, unless overridden with @option{--user}, a dummy home
  4809. directory is created that matches the current user's home directory, and
  4810. @file{/etc/passwd} is configured accordingly.
  4811. The spawned process runs as the current user outside the container. Inside
  4812. the container, it has the same UID and GID as the current user, unless
  4813. @option{--user} is passed (see below).
  4814. @item --network
  4815. @itemx -N
  4816. For containers, share the network namespace with the host system.
  4817. Containers created without this flag only have access to the loopback
  4818. device.
  4819. @item --link-profile
  4820. @itemx -P
  4821. For containers, link the environment profile to @file{~/.guix-profile}
  4822. within the container and set @code{GUIX_ENVIRONMENT} to that.
  4823. This is equivalent to making @file{~/.guix-profile} a symlink to the
  4824. actual profile within the container.
  4825. Linking will fail and abort the environment if the directory already
  4826. exists, which will certainly be the case if @command{guix shell}
  4827. was invoked in the user's home directory.
  4828. Certain packages are configured to look in @file{~/.guix-profile} for
  4829. configuration files and data;@footnote{For example, the
  4830. @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
  4831. for additional fonts.} @option{--link-profile} allows these programs to
  4832. behave as expected within the environment.
  4833. @item --user=@var{user}
  4834. @itemx -u @var{user}
  4835. For containers, use the username @var{user} in place of the current
  4836. user. The generated @file{/etc/passwd} entry within the container will
  4837. contain the name @var{user}, the home directory will be
  4838. @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
  4839. the UID and GID inside the container are 1000. @var{user}
  4840. need not exist on the system.
  4841. Additionally, any shared or exposed path (see @option{--share} and
  4842. @option{--expose} respectively) whose target is within the current user's
  4843. home directory will be remapped relative to @file{/home/USER}; this
  4844. includes the automatic mapping of the current working directory.
  4845. @example
  4846. # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
  4847. cd $HOME/wd
  4848. guix shell --container --user=foo \
  4849. --expose=$HOME/test \
  4850. --expose=/tmp/target=$HOME/target
  4851. @end example
  4852. While this will limit the leaking of user identity through home paths
  4853. and each of the user fields, this is only one useful component of a
  4854. broader privacy/anonymity solution---not one in and of itself.
  4855. @item --no-cwd
  4856. For containers, the default behavior is to share the current working
  4857. directory with the isolated container and immediately change to that
  4858. directory within the container. If this is undesirable,
  4859. @option{--no-cwd} will cause the current working directory to @emph{not}
  4860. be automatically shared and will change to the user's home directory
  4861. within the container instead. See also @option{--user}.
  4862. @item --expose=@var{source}[=@var{target}]
  4863. @itemx --share=@var{source}[=@var{target}]
  4864. For containers, @option{--expose} (resp. @option{--share}) exposes the
  4865. file system @var{source} from the host system as the read-only
  4866. (resp. writable) file system @var{target} within the container. If
  4867. @var{target} is not specified, @var{source} is used as the target mount
  4868. point in the container.
  4869. The example below spawns a Guile REPL in a container in which the user's
  4870. home directory is accessible read-only via the @file{/exchange}
  4871. directory:
  4872. @example
  4873. guix shell --container --expose=$HOME=/exchange guile -- guile
  4874. @end example
  4875. @item --rebuild-cache
  4876. @cindex caching, of profiles
  4877. @cindex caching, in @command{guix shell}
  4878. In most cases, @command{guix shell} caches the environment so that
  4879. subsequent uses are instantaneous. Least-recently used cache entries
  4880. are periodically removed. The cache is also invalidated, when using
  4881. @option{--file} or @option{--manifest}, anytime the corresponding file
  4882. is modified.
  4883. The @option{--rebuild-cache} forces the cached environment to be
  4884. refreshed. This is useful when using @option{--file} or
  4885. @option{--manifest} and the @command{guix.scm} or @command{manifest.scm}
  4886. file has external dependencies, or if its behavior depends, say, on
  4887. environment variables.
  4888. @item --root=@var{file}
  4889. @itemx -r @var{file}
  4890. @cindex persistent environment
  4891. @cindex garbage collector root, for environments
  4892. Make @var{file} a symlink to the profile for this environment, and
  4893. register it as a garbage collector root.
  4894. This is useful if you want to protect your environment from garbage
  4895. collection, to make it ``persistent''.
  4896. When this option is omitted, @command{guix shell} caches profiles so
  4897. that subsequent uses of the same environment are instantaneous---this is
  4898. comparable to using @option{--root} except that @command{guix shell}
  4899. takes care of periodically removing the least-recently used garbage
  4900. collector roots.
  4901. In some cases, @command{guix shell} does not cache profiles---e.g., if
  4902. transformation options such as @option{--with-latest} are used. In
  4903. those cases, the environment is protected from garbage collection only
  4904. for the duration of the @command{guix shell} session. This means that
  4905. next time you recreate the same environment, you could have to rebuild
  4906. or re-download packages.
  4907. @xref{Invoking guix gc}, for more on GC roots.
  4908. @end table
  4909. @command{guix shell} also supports all of the common build options that
  4910. @command{guix build} supports (@pxref{Common Build Options}) as well as
  4911. package transformation options (@pxref{Package Transformation Options}).
  4912. @node Invoking guix environment
  4913. @section Invoking @command{guix environment}
  4914. The purpose of @command{guix environment} is to assist in creating
  4915. development environments.
  4916. @quotation Deprecation warning
  4917. The @command{guix environment} command is deprecated in favor of
  4918. @command{guix shell}, which performs similar functions but is more
  4919. convenient to use. @xref{Invoking guix shell}.
  4920. Being deprecated, @command{guix environment} is slated for eventual
  4921. removal, but the Guix project is committed to keeping it until May 1st,
  4922. 2023. Please get in touch with us at @email{guix-devel@@gnu.org} if you
  4923. would like to discuss it.
  4924. @end quotation
  4925. The general syntax is:
  4926. @example
  4927. guix environment @var{options} @var{package}@dots{}
  4928. @end example
  4929. The following example spawns a new shell set up for the development of
  4930. GNU@tie{}Guile:
  4931. @example
  4932. guix environment guile
  4933. @end example
  4934. If the needed dependencies are not built yet, @command{guix environment}
  4935. automatically builds them. The environment of the new shell is an
  4936. augmented version of the environment that @command{guix environment} was
  4937. run in. It contains the necessary search paths for building the given
  4938. package added to the existing environment variables. To create
  4939. a ``pure'' environment, in which the original environment variables have
  4940. been unset, use the @option{--pure} option@footnote{Users sometimes
  4941. wrongfully augment environment variables such as @env{PATH} in their
  4942. @file{~/.bashrc} file. As a consequence, when @command{guix
  4943. environment} launches it, Bash may read @file{~/.bashrc}, thereby
  4944. introducing ``impurities'' in these environment variables. It is an
  4945. error to define such environment variables in @file{.bashrc}; instead,
  4946. they should be defined in @file{.bash_profile}, which is sourced only by
  4947. log-in shells. @xref{Bash Startup Files,,, bash, The GNU Bash Reference
  4948. Manual}, for details on Bash start-up files.}.
  4949. Exiting from a Guix environment is the same as exiting from the shell,
  4950. and will place the user back in the old environment before @command{guix
  4951. environment} was invoked. The next garbage collection (@pxref{Invoking
  4952. guix gc}) will clean up packages that were installed from within the
  4953. environment and are no longer used outside of it.
  4954. @vindex GUIX_ENVIRONMENT
  4955. @command{guix environment} defines the @env{GUIX_ENVIRONMENT}
  4956. variable in the shell it spawns; its value is the file name of the
  4957. profile of this environment. This allows users to, say, define a
  4958. specific prompt for development environments in their @file{.bashrc}
  4959. (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
  4960. @example
  4961. if [ -n "$GUIX_ENVIRONMENT" ]
  4962. then
  4963. export PS1="\u@@\h \w [dev]\$ "
  4964. fi
  4965. @end example
  4966. @noindent
  4967. ...@: or to browse the profile:
  4968. @example
  4969. $ ls "$GUIX_ENVIRONMENT/bin"
  4970. @end example
  4971. Additionally, more than one package may be specified, in which case the
  4972. union of the inputs for the given packages are used. For example, the
  4973. command below spawns a shell where all of the dependencies of both Guile
  4974. and Emacs are available:
  4975. @example
  4976. guix environment guile emacs
  4977. @end example
  4978. Sometimes an interactive shell session is not desired. An arbitrary
  4979. command may be invoked by placing the @code{--} token to separate the
  4980. command from the rest of the arguments:
  4981. @example
  4982. guix environment guile -- make -j4
  4983. @end example
  4984. In other situations, it is more convenient to specify the list of
  4985. packages needed in the environment. For example, the following command
  4986. runs @command{python} from an environment containing Python@tie{}3 and
  4987. NumPy:
  4988. @example
  4989. guix environment --ad-hoc python-numpy python -- python3
  4990. @end example
  4991. Furthermore, one might want the dependencies of a package and also some
  4992. additional packages that are not build-time or runtime dependencies, but
  4993. are useful when developing nonetheless. Because of this, the
  4994. @option{--ad-hoc} flag is positional. Packages appearing before
  4995. @option{--ad-hoc} are interpreted as packages whose dependencies will be
  4996. added to the environment. Packages appearing after are interpreted as
  4997. packages that will be added to the environment directly. For example,
  4998. the following command creates a Guix development environment that
  4999. additionally includes Git and strace:
  5000. @example
  5001. guix environment --pure guix --ad-hoc git strace
  5002. @end example
  5003. @cindex container
  5004. Sometimes it is desirable to isolate the environment as much as
  5005. possible, for maximal purity and reproducibility. In particular, when
  5006. using Guix on a host distro that is not Guix System, it is desirable to
  5007. prevent access to @file{/usr/bin} and other system-wide resources from
  5008. the development environment. For example, the following command spawns
  5009. a Guile REPL in a ``container'' where only the store and the current
  5010. working directory are mounted:
  5011. @example
  5012. guix environment --ad-hoc --container guile -- guile
  5013. @end example
  5014. @quotation Note
  5015. The @option{--container} option requires Linux-libre 3.19 or newer.
  5016. @end quotation
  5017. @cindex certificates
  5018. Another typical use case for containers is to run security-sensitive
  5019. applications such as a web browser. To run Eolie, we must expose and
  5020. share some files and directories; we include @code{nss-certs} and expose
  5021. @file{/etc/ssl/certs/} for HTTPS authentication; finally we preserve the
  5022. @env{DISPLAY} environment variable since containerized graphical
  5023. applications won't display without it.
  5024. @example
  5025. guix environment --preserve='^DISPLAY$' --container --network \
  5026. --expose=/etc/machine-id \
  5027. --expose=/etc/ssl/certs/ \
  5028. --share=$HOME/.local/share/eolie/=$HOME/.local/share/eolie/ \
  5029. --ad-hoc eolie nss-certs dbus -- eolie
  5030. @end example
  5031. The available options are summarized below.
  5032. @table @code
  5033. @item --check
  5034. Set up the environment and check whether the shell would clobber
  5035. environment variables. @xref{Invoking guix shell, @option{--check}},
  5036. for more info.
  5037. @item --root=@var{file}
  5038. @itemx -r @var{file}
  5039. @cindex persistent environment
  5040. @cindex garbage collector root, for environments
  5041. Make @var{file} a symlink to the profile for this environment, and
  5042. register it as a garbage collector root.
  5043. This is useful if you want to protect your environment from garbage
  5044. collection, to make it ``persistent''.
  5045. When this option is omitted, the environment is protected from garbage
  5046. collection only for the duration of the @command{guix environment}
  5047. session. This means that next time you recreate the same environment,
  5048. you could have to rebuild or re-download packages. @xref{Invoking guix
  5049. gc}, for more on GC roots.
  5050. @item --expression=@var{expr}
  5051. @itemx -e @var{expr}
  5052. Create an environment for the package or list of packages that
  5053. @var{expr} evaluates to.
  5054. For example, running:
  5055. @example
  5056. guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
  5057. @end example
  5058. starts a shell with the environment for this specific variant of the
  5059. PETSc package.
  5060. Running:
  5061. @example
  5062. guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
  5063. @end example
  5064. starts a shell with all the base system packages available.
  5065. The above commands only use the default output of the given packages.
  5066. To select other outputs, two element tuples can be specified:
  5067. @example
  5068. guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
  5069. @end example
  5070. @item --load=@var{file}
  5071. @itemx -l @var{file}
  5072. Create an environment for the package or list of packages that the code
  5073. within @var{file} evaluates to.
  5074. As an example, @var{file} might contain a definition like this
  5075. (@pxref{Defining Packages}):
  5076. @lisp
  5077. @verbatiminclude environment-gdb.scm
  5078. @end lisp
  5079. @item --manifest=@var{file}
  5080. @itemx -m @var{file}
  5081. Create an environment for the packages contained in the manifest object
  5082. returned by the Scheme code in @var{file}. This option can be repeated
  5083. several times, in which case the manifests are concatenated.
  5084. This is similar to the same-named option in @command{guix package}
  5085. (@pxref{profile-manifest, @option{--manifest}}) and uses the same
  5086. manifest files.
  5087. @xref{shell-export-manifest, @command{guix shell --export-manifest}},
  5088. for information on how to ``convert'' command-line options into a
  5089. manifest.
  5090. @item --ad-hoc
  5091. Include all specified packages in the resulting environment, as if an
  5092. @i{ad hoc} package were defined with them as inputs. This option is
  5093. useful for quickly creating an environment without having to write a
  5094. package expression to contain the desired inputs.
  5095. For instance, the command:
  5096. @example
  5097. guix environment --ad-hoc guile guile-sdl -- guile
  5098. @end example
  5099. runs @command{guile} in an environment where Guile and Guile-SDL are
  5100. available.
  5101. Note that this example implicitly asks for the default output of
  5102. @code{guile} and @code{guile-sdl}, but it is possible to ask for a
  5103. specific output---e.g., @code{glib:bin} asks for the @code{bin} output
  5104. of @code{glib} (@pxref{Packages with Multiple Outputs}).
  5105. This option may be composed with the default behavior of @command{guix
  5106. environment}. Packages appearing before @option{--ad-hoc} are
  5107. interpreted as packages whose dependencies will be added to the
  5108. environment, the default behavior. Packages appearing after are
  5109. interpreted as packages that will be added to the environment directly.
  5110. @item --profile=@var{profile}
  5111. @itemx -p @var{profile}
  5112. Create an environment containing the packages installed in @var{profile}.
  5113. Use @command{guix package} (@pxref{Invoking guix package}) to create
  5114. and manage profiles.
  5115. @item --pure
  5116. Unset existing environment variables when building the new environment, except
  5117. those specified with @option{--preserve} (see below). This has the effect of
  5118. creating an environment in which search paths only contain package inputs.
  5119. @item --preserve=@var{regexp}
  5120. @itemx -E @var{regexp}
  5121. When used alongside @option{--pure}, preserve the environment variables
  5122. matching @var{regexp}---in other words, put them on a ``white list'' of
  5123. environment variables that must be preserved. This option can be repeated
  5124. several times.
  5125. @example
  5126. guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
  5127. -- mpirun @dots{}
  5128. @end example
  5129. This example runs @command{mpirun} in a context where the only environment
  5130. variables defined are @env{PATH}, environment variables whose name starts
  5131. with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
  5132. @env{USER}, etc.).
  5133. @item --search-paths
  5134. Display the environment variable definitions that make up the
  5135. environment.
  5136. @item --system=@var{system}
  5137. @itemx -s @var{system}
  5138. Attempt to build for @var{system}---e.g., @code{i686-linux}.
  5139. @item --container
  5140. @itemx -C
  5141. @cindex container
  5142. Run @var{command} within an isolated container. The current working
  5143. directory outside the container is mapped inside the container.
  5144. Additionally, unless overridden with @option{--user}, a dummy home
  5145. directory is created that matches the current user's home directory, and
  5146. @file{/etc/passwd} is configured accordingly.
  5147. The spawned process runs as the current user outside the container. Inside
  5148. the container, it has the same UID and GID as the current user, unless
  5149. @option{--user} is passed (see below).
  5150. @item --network
  5151. @itemx -N
  5152. For containers, share the network namespace with the host system.
  5153. Containers created without this flag only have access to the loopback
  5154. device.
  5155. @item --link-profile
  5156. @itemx -P
  5157. For containers, link the environment profile to @file{~/.guix-profile}
  5158. within the container and set @code{GUIX_ENVIRONMENT} to that.
  5159. This is equivalent to making @file{~/.guix-profile} a symlink to the
  5160. actual profile within the container.
  5161. Linking will fail and abort the environment if the directory already
  5162. exists, which will certainly be the case if @command{guix environment}
  5163. was invoked in the user's home directory.
  5164. Certain packages are configured to look in @file{~/.guix-profile} for
  5165. configuration files and data;@footnote{For example, the
  5166. @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
  5167. for additional fonts.} @option{--link-profile} allows these programs to
  5168. behave as expected within the environment.
  5169. @item --user=@var{user}
  5170. @itemx -u @var{user}
  5171. For containers, use the username @var{user} in place of the current
  5172. user. The generated @file{/etc/passwd} entry within the container will
  5173. contain the name @var{user}, the home directory will be
  5174. @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
  5175. the UID and GID inside the container are 1000. @var{user}
  5176. need not exist on the system.
  5177. Additionally, any shared or exposed path (see @option{--share} and
  5178. @option{--expose} respectively) whose target is within the current user's
  5179. home directory will be remapped relative to @file{/home/USER}; this
  5180. includes the automatic mapping of the current working directory.
  5181. @example
  5182. # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
  5183. cd $HOME/wd
  5184. guix environment --container --user=foo \
  5185. --expose=$HOME/test \
  5186. --expose=/tmp/target=$HOME/target
  5187. @end example
  5188. While this will limit the leaking of user identity through home paths
  5189. and each of the user fields, this is only one useful component of a
  5190. broader privacy/anonymity solution---not one in and of itself.
  5191. @item --no-cwd
  5192. For containers, the default behavior is to share the current working
  5193. directory with the isolated container and immediately change to that
  5194. directory within the container. If this is undesirable,
  5195. @option{--no-cwd} will cause the current working directory to @emph{not}
  5196. be automatically shared and will change to the user's home directory
  5197. within the container instead. See also @option{--user}.
  5198. @item --expose=@var{source}[=@var{target}]
  5199. @itemx --share=@var{source}[=@var{target}]
  5200. For containers, @option{--expose} (resp. @option{--share}) exposes the
  5201. file system @var{source} from the host system as the read-only
  5202. (resp. writable) file system @var{target} within the container. If
  5203. @var{target} is not specified, @var{source} is used as the target mount
  5204. point in the container.
  5205. The example below spawns a Guile REPL in a container in which the user's
  5206. home directory is accessible read-only via the @file{/exchange}
  5207. directory:
  5208. @example
  5209. guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
  5210. @end example
  5211. @end table
  5212. @command{guix environment}
  5213. also supports all of the common build options that @command{guix
  5214. build} supports (@pxref{Common Build Options}) as well as package
  5215. transformation options (@pxref{Package Transformation Options}).
  5216. @node Invoking guix pack
  5217. @section Invoking @command{guix pack}
  5218. Occasionally you want to pass software to people who are not (yet!)
  5219. lucky enough to be using Guix. You'd tell them to run @command{guix
  5220. package -i @var{something}}, but that's not possible in this case. This
  5221. is where @command{guix pack} comes in.
  5222. @quotation Note
  5223. If you are looking for ways to exchange binaries among machines that
  5224. already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
  5225. publish}, and @ref{Invoking guix archive}.
  5226. @end quotation
  5227. @cindex pack
  5228. @cindex bundle
  5229. @cindex application bundle
  5230. @cindex software bundle
  5231. The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
  5232. @dfn{software bundle}: it creates a tarball or some other archive
  5233. containing the binaries of the software you're interested in, and all
  5234. its dependencies. The resulting archive can be used on any machine that
  5235. does not have Guix, and people can run the exact same binaries as those
  5236. you have with Guix. The pack itself is created in a bit-reproducible
  5237. fashion, so anyone can verify that it really contains the build results
  5238. that you pretend to be shipping.
  5239. For example, to create a bundle containing Guile, Emacs, Geiser, and all
  5240. their dependencies, you can run:
  5241. @example
  5242. $ guix pack guile emacs emacs-geiser
  5243. @dots{}
  5244. /gnu/store/@dots{}-pack.tar.gz
  5245. @end example
  5246. The result here is a tarball containing a @file{/gnu/store} directory
  5247. with all the relevant packages. The resulting tarball contains a
  5248. @dfn{profile} with the three packages of interest; the profile is the
  5249. same as would be created by @command{guix package -i}. It is this
  5250. mechanism that is used to create Guix's own standalone binary tarball
  5251. (@pxref{Binary Installation}).
  5252. Users of this pack would have to run
  5253. @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
  5254. find inconvenient. To work around it, you can create, say, a
  5255. @file{/opt/gnu/bin} symlink to the profile:
  5256. @example
  5257. guix pack -S /opt/gnu/bin=bin guile emacs emacs-geiser
  5258. @end example
  5259. @noindent
  5260. That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
  5261. @cindex relocatable binaries, with @command{guix pack}
  5262. What if the recipient of your pack does not have root privileges on
  5263. their machine, and thus cannot unpack it in the root file system? In
  5264. that case, you will want to use the @option{--relocatable} option (see
  5265. below). This option produces @dfn{relocatable binaries}, meaning they
  5266. they can be placed anywhere in the file system hierarchy: in the example
  5267. above, users can unpack your tarball in their home directory and
  5268. directly run @file{./opt/gnu/bin/guile}.
  5269. @cindex Docker, build an image with guix pack
  5270. Alternatively, you can produce a pack in the Docker image format using
  5271. the following command:
  5272. @example
  5273. guix pack -f docker -S /bin=bin guile guile-readline
  5274. @end example
  5275. @noindent
  5276. The result is a tarball that can be passed to the @command{docker load}
  5277. command, followed by @code{docker run}:
  5278. @example
  5279. docker load < @var{file}
  5280. docker run -ti guile-guile-readline /bin/guile
  5281. @end example
  5282. @noindent
  5283. where @var{file} is the image returned by @var{guix pack}, and
  5284. @code{guile-guile-readline} is its ``image tag''. See the
  5285. @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
  5286. documentation} for more information.
  5287. @cindex Singularity, build an image with guix pack
  5288. @cindex SquashFS, build an image with guix pack
  5289. Yet another option is to produce a SquashFS image with the following
  5290. command:
  5291. @example
  5292. guix pack -f squashfs bash guile emacs emacs-geiser
  5293. @end example
  5294. @noindent
  5295. The result is a SquashFS file system image that can either be mounted or
  5296. directly be used as a file system container image with the
  5297. @uref{https://www.sylabs.io/docs/, Singularity container execution
  5298. environment}, using commands like @command{singularity shell} or
  5299. @command{singularity exec}.
  5300. Several command-line options allow you to customize your pack:
  5301. @table @code
  5302. @item --format=@var{format}
  5303. @itemx -f @var{format}
  5304. Produce a pack in the given @var{format}.
  5305. The available formats are:
  5306. @table @code
  5307. @item tarball
  5308. This is the default format. It produces a tarball containing all the
  5309. specified binaries and symlinks.
  5310. @item docker
  5311. This produces a tarball that follows the
  5312. @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
  5313. Docker Image Specification}. The ``repository name'' as it appears in
  5314. the output of the @command{docker images} command is computed from
  5315. package names passed on the command line or in the manifest file.
  5316. @item squashfs
  5317. This produces a SquashFS image containing all the specified binaries and
  5318. symlinks, as well as empty mount points for virtual file systems like
  5319. procfs.
  5320. @quotation Note
  5321. Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
  5322. For that reason, @command{guix pack -f squashfs} always implies @code{-S
  5323. /bin=bin}. Thus, your @command{guix pack} invocation must always start
  5324. with something like:
  5325. @example
  5326. guix pack -f squashfs bash @dots{}
  5327. @end example
  5328. If you forget the @code{bash} (or similar) package, @command{singularity
  5329. run} and @command{singularity exec} will fail with an unhelpful ``no
  5330. such file or directory'' message.
  5331. @end quotation
  5332. @item deb
  5333. This produces a Debian archive (a package with the @samp{.deb} file
  5334. extension) containing all the specified binaries and symbolic links,
  5335. that can be installed on top of any dpkg-based GNU(/Linux) distribution.
  5336. Advanced options can be revealed via the @option{--help-deb-format}
  5337. option. They allow embedding control files for more fine-grained
  5338. control, such as activating specific triggers or providing a maintainer
  5339. configure script to run arbitrary setup code upon installation.
  5340. @example
  5341. guix pack -f deb -C xz -S /usr/bin/hello=bin/hello hello
  5342. @end example
  5343. @quotation Note
  5344. Because archives produced with @command{guix pack} contain a collection
  5345. of store items and because each @command{dpkg} package must not have
  5346. conflicting files, in practice that means you likely won't be able to
  5347. install more than one such archive on a given system.
  5348. @end quotation
  5349. @quotation Warning
  5350. @command{dpkg} will assume ownership of any files contained in the pack
  5351. that it does @emph{not} know about. It is unwise to install
  5352. Guix-produced @samp{.deb} files on a system where @file{/gnu/store} is
  5353. shared by other software, such as a Guix installation or other, non-deb
  5354. packs.
  5355. @end quotation
  5356. @end table
  5357. @cindex relocatable binaries
  5358. @item --relocatable
  5359. @itemx -R
  5360. Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
  5361. anywhere in the file system hierarchy and run from there.
  5362. When this option is passed once, the resulting binaries require support for
  5363. @dfn{user namespaces} in the kernel Linux; when passed
  5364. @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
  5365. PRoot support, can be thought of as the abbreviation of ``Really
  5366. Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to
  5367. other techniques if user namespaces are unavailable, and essentially
  5368. work anywhere---see below for the implications.
  5369. For example, if you create a pack containing Bash with:
  5370. @example
  5371. guix pack -RR -S /mybin=bin bash
  5372. @end example
  5373. @noindent
  5374. ...@: you can copy that pack to a machine that lacks Guix, and from your
  5375. home directory as a normal user, run:
  5376. @example
  5377. tar xf pack.tar.gz
  5378. ./mybin/sh
  5379. @end example
  5380. @noindent
  5381. In that shell, if you type @code{ls /gnu/store}, you'll notice that
  5382. @file{/gnu/store} shows up and contains all the dependencies of
  5383. @code{bash}, even though the machine actually lacks @file{/gnu/store}
  5384. altogether! That is probably the simplest way to deploy Guix-built
  5385. software on a non-Guix machine.
  5386. @quotation Note
  5387. By default, relocatable binaries rely on the @dfn{user namespace} feature of
  5388. the kernel Linux, which allows unprivileged users to mount or change root.
  5389. Old versions of Linux did not support it, and some GNU/Linux distributions
  5390. turn it off.
  5391. To produce relocatable binaries that work even in the absence of user
  5392. namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
  5393. case, binaries will try user namespace support and fall back to another
  5394. @dfn{execution engine} if user namespaces are not supported. The
  5395. following execution engines are supported:
  5396. @table @code
  5397. @item default
  5398. Try user namespaces and fall back to PRoot if user namespaces are not
  5399. supported (see below).
  5400. @item performance
  5401. Try user namespaces and fall back to Fakechroot if user namespaces are
  5402. not supported (see below).
  5403. @item userns
  5404. Run the program through user namespaces and abort if they are not
  5405. supported.
  5406. @item proot
  5407. Run through PRoot. The @uref{https://proot-me.github.io/, PRoot} program
  5408. provides the necessary
  5409. support for file system virtualization. It achieves that by using the
  5410. @code{ptrace} system call on the running program. This approach has the
  5411. advantage to work without requiring special kernel support, but it incurs
  5412. run-time overhead every time a system call is made.
  5413. @item fakechroot
  5414. Run through Fakechroot. @uref{https://github.com/dex4er/fakechroot/,
  5415. Fakechroot} virtualizes file system accesses by intercepting calls to C
  5416. library functions such as @code{open}, @code{stat}, @code{exec}, and so
  5417. on. Unlike PRoot, it incurs very little overhead. However, it does not
  5418. always work: for example, some file system accesses made from within the
  5419. C library are not intercepted, and file system accesses made @i{via}
  5420. direct syscalls are not intercepted either, leading to erratic behavior.
  5421. @end table
  5422. @vindex GUIX_EXECUTION_ENGINE
  5423. When running a wrapped program, you can explicitly request one of the
  5424. execution engines listed above by setting the
  5425. @env{GUIX_EXECUTION_ENGINE} environment variable accordingly.
  5426. @end quotation
  5427. @cindex entry point, for Docker images
  5428. @item --entry-point=@var{command}
  5429. Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
  5430. format supports it---currently @code{docker} and @code{squashfs} (Singularity)
  5431. support it. @var{command} must be relative to the profile contained in the
  5432. pack.
  5433. The entry point specifies the command that tools like @code{docker run} or
  5434. @code{singularity run} automatically start by default. For example, you can
  5435. do:
  5436. @example
  5437. guix pack -f docker --entry-point=bin/guile guile
  5438. @end example
  5439. The resulting pack can easily be loaded and @code{docker run} with no extra
  5440. arguments will spawn @code{bin/guile}:
  5441. @example
  5442. docker load -i pack.tar.gz
  5443. docker run @var{image-id}
  5444. @end example
  5445. @item --expression=@var{expr}
  5446. @itemx -e @var{expr}
  5447. Consider the package @var{expr} evaluates to.
  5448. This has the same purpose as the same-named option in @command{guix
  5449. build} (@pxref{Additional Build Options, @option{--expression} in
  5450. @command{guix build}}).
  5451. @item --manifest=@var{file}
  5452. @itemx -m @var{file}
  5453. Use the packages contained in the manifest object returned by the Scheme
  5454. code in @var{file}. This option can be repeated several times, in which
  5455. case the manifests are concatenated.
  5456. This has a similar purpose as the same-named option in @command{guix
  5457. package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
  5458. same manifest files. It allows you to define a collection of packages
  5459. once and use it both for creating profiles and for creating archives
  5460. for use on machines that do not have Guix installed. Note that you can
  5461. specify @emph{either} a manifest file @emph{or} a list of packages,
  5462. but not both.
  5463. @xref{shell-export-manifest, @command{guix shell --export-manifest}},
  5464. for information on how to ``convert'' command-line options into a
  5465. manifest.
  5466. @item --system=@var{system}
  5467. @itemx -s @var{system}
  5468. Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
  5469. the system type of the build host.
  5470. @item --target=@var{triplet}
  5471. @cindex cross-compilation
  5472. Cross-build for @var{triplet}, which must be a valid GNU triplet, such
  5473. as @code{"aarch64-linux-gnu"} (@pxref{Specifying target triplets, GNU
  5474. configuration triplets,, autoconf, Autoconf}).
  5475. @item --compression=@var{tool}
  5476. @itemx -C @var{tool}
  5477. Compress the resulting tarball using @var{tool}---one of @code{gzip},
  5478. @code{zstd}, @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no
  5479. compression.
  5480. @item --symlink=@var{spec}
  5481. @itemx -S @var{spec}
  5482. Add the symlinks specified by @var{spec} to the pack. This option can
  5483. appear several times.
  5484. @var{spec} has the form @code{@var{source}=@var{target}}, where
  5485. @var{source} is the symlink that will be created and @var{target} is the
  5486. symlink target.
  5487. For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
  5488. symlink pointing to the @file{bin} sub-directory of the profile.
  5489. @item --save-provenance
  5490. Save provenance information for the packages passed on the command line.
  5491. Provenance information includes the URL and commit of the channels in use
  5492. (@pxref{Channels}).
  5493. Provenance information is saved in the
  5494. @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
  5495. usual package metadata---the name and version of each package, their
  5496. propagated inputs, and so on. It is useful information to the recipient of
  5497. the pack, who then knows how the pack was (supposedly) obtained.
  5498. This option is not enabled by default because, like timestamps, provenance
  5499. information contributes nothing to the build process. In other words, there
  5500. is an infinity of channel URLs and commit IDs that can lead to the same pack.
  5501. Recording such ``silent'' metadata in the output thus potentially breaks the
  5502. source-to-binary bitwise reproducibility property.
  5503. @item --root=@var{file}
  5504. @itemx -r @var{file}
  5505. @cindex garbage collector root, for packs
  5506. Make @var{file} a symlink to the resulting pack, and register it as a garbage
  5507. collector root.
  5508. @item --localstatedir
  5509. @itemx --profile-name=@var{name}
  5510. Include the ``local state directory'', @file{/var/guix}, in the resulting
  5511. pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
  5512. profile---by default @var{name} is @code{guix-profile}, which corresponds to
  5513. @file{~root/.guix-profile}.
  5514. @file{/var/guix} contains the store database (@pxref{The Store}) as well
  5515. as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
  5516. the pack means that the store is ``complete'' and manageable by Guix;
  5517. not providing it pack means that the store is ``dead'': items cannot be
  5518. added to it or removed from it after extraction of the pack.
  5519. One use case for this is the Guix self-contained binary tarball
  5520. (@pxref{Binary Installation}).
  5521. @item --derivation
  5522. @itemx -d
  5523. Print the name of the derivation that builds the pack.
  5524. @item --bootstrap
  5525. Use the bootstrap binaries to build the pack. This option is only
  5526. useful to Guix developers.
  5527. @end table
  5528. In addition, @command{guix pack} supports all the common build options
  5529. (@pxref{Common Build Options}) and all the package transformation
  5530. options (@pxref{Package Transformation Options}).
  5531. @node The GCC toolchain
  5532. @section The GCC toolchain
  5533. @cindex GCC
  5534. @cindex ld-wrapper
  5535. @cindex linker wrapper
  5536. @cindex toolchain, for C development
  5537. @cindex toolchain, for Fortran development
  5538. If you need a complete toolchain for compiling and linking C or C++
  5539. source code, use the @code{gcc-toolchain} package. This package
  5540. provides a complete GCC toolchain for C/C++ development, including GCC
  5541. itself, the GNU C Library (headers and binaries, plus debugging symbols
  5542. in the @code{debug} output), Binutils, and a linker wrapper.
  5543. The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
  5544. passed to the linker, add corresponding @code{-rpath} arguments, and
  5545. invoke the actual linker with this new set of arguments. You can instruct the
  5546. wrapper to refuse to link against libraries not in the store by setting the
  5547. @env{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
  5548. The package @code{gfortran-toolchain} provides a complete GCC toolchain
  5549. for Fortran development. For other languages, please use
  5550. @samp{guix search gcc toolchain} (@pxref{guix-search,, Invoking guix package}).
  5551. @node Invoking guix git authenticate
  5552. @section Invoking @command{guix git authenticate}
  5553. The @command{guix git authenticate} command authenticates a Git checkout
  5554. following the same rule as for channels (@pxref{channel-authentication,
  5555. channel authentication}). That is, starting from a given commit, it
  5556. ensures that all subsequent commits are signed by an OpenPGP key whose
  5557. fingerprint appears in the @file{.guix-authorizations} file of its
  5558. parent commit(s).
  5559. You will find this command useful if you maintain a channel. But in
  5560. fact, this authentication mechanism is useful in a broader context, so
  5561. you might want to use it for Git repositories that have nothing to do
  5562. with Guix.
  5563. The general syntax is:
  5564. @example
  5565. guix git authenticate @var{commit} @var{signer} [@var{options}@dots{}]
  5566. @end example
  5567. By default, this command authenticates the Git checkout in the current
  5568. directory; it outputs nothing and exits with exit code zero on success
  5569. and non-zero on failure. @var{commit} above denotes the first commit
  5570. where authentication takes place, and @var{signer} is the OpenPGP
  5571. fingerprint of public key used to sign @var{commit}. Together, they
  5572. form a ``channel introduction'' (@pxref{channel-authentication, channel
  5573. introduction}). The options below allow you to fine-tune the process.
  5574. @table @code
  5575. @item --repository=@var{directory}
  5576. @itemx -r @var{directory}
  5577. Open the Git repository in @var{directory} instead of the current
  5578. directory.
  5579. @item --keyring=@var{reference}
  5580. @itemx -k @var{reference}
  5581. Load OpenPGP keyring from @var{reference}, the reference of a branch
  5582. such as @code{origin/keyring} or @code{my-keyring}. The branch must
  5583. contain OpenPGP public keys in @file{.key} files, either in binary form
  5584. or ``ASCII-armored''. By default the keyring is loaded from the branch
  5585. named @code{keyring}.
  5586. @item --stats
  5587. Display commit signing statistics upon completion.
  5588. @item --cache-key=@var{key}
  5589. Previously-authenticated commits are cached in a file under
  5590. @file{~/.cache/guix/authentication}. This option forces the cache to be
  5591. stored in file @var{key} in that directory.
  5592. @item --historical-authorizations=@var{file}
  5593. By default, any commit whose parent commit(s) lack the
  5594. @file{.guix-authorizations} file is considered inauthentic. In
  5595. contrast, this option considers the authorizations in @var{file} for any
  5596. commit that lacks @file{.guix-authorizations}. The format of @var{file}
  5597. is the same as that of @file{.guix-authorizations}
  5598. (@pxref{channel-authorizations, @file{.guix-authorizations} format}).
  5599. @end table
  5600. @c *********************************************************************
  5601. @node Programming Interface
  5602. @chapter Programming Interface
  5603. GNU Guix provides several Scheme programming interfaces (APIs) to
  5604. define, build, and query packages. The first interface allows users to
  5605. write high-level package definitions. These definitions refer to
  5606. familiar packaging concepts, such as the name and version of a package,
  5607. its build system, and its dependencies. These definitions can then be
  5608. turned into concrete build actions.
  5609. Build actions are performed by the Guix daemon, on behalf of users. In a
  5610. standard setup, the daemon has write access to the store---the
  5611. @file{/gnu/store} directory---whereas users do not. The recommended
  5612. setup also has the daemon perform builds in chroots, under specific
  5613. build users, to minimize interference with the rest of the system.
  5614. @cindex derivation
  5615. Lower-level APIs are available to interact with the daemon and the
  5616. store. To instruct the daemon to perform a build action, users actually
  5617. provide it with a @dfn{derivation}. A derivation is a low-level
  5618. representation of the build actions to be taken, and the environment in
  5619. which they should occur---derivations are to package definitions what
  5620. assembly is to C programs. The term ``derivation'' comes from the fact
  5621. that build results @emph{derive} from them.
  5622. This chapter describes all these APIs in turn, starting from high-level
  5623. package definitions.
  5624. @menu
  5625. * Package Modules:: Packages from the programmer's viewpoint.
  5626. * Defining Packages:: Defining new packages.
  5627. * Defining Package Variants:: Customizing packages.
  5628. * Build Systems:: Specifying how packages are built.
  5629. * Build Phases:: Phases of the build process of a package.
  5630. * Build Utilities:: Helpers for your package definitions and more.
  5631. * Search Paths:: Declaring search path environment variables.
  5632. * The Store:: Manipulating the package store.
  5633. * Derivations:: Low-level interface to package derivations.
  5634. * The Store Monad:: Purely functional interface to the store.
  5635. * G-Expressions:: Manipulating build expressions.
  5636. * Invoking guix repl:: Programming Guix in Guile
  5637. @end menu
  5638. @node Package Modules
  5639. @section Package Modules
  5640. From a programming viewpoint, the package definitions of the
  5641. GNU distribution are provided by Guile modules in the @code{(gnu packages
  5642. @dots{})} name space@footnote{Note that packages under the @code{(gnu
  5643. packages @dots{})} module name space are not necessarily ``GNU
  5644. packages''. This module naming scheme follows the usual Guile module
  5645. naming convention: @code{gnu} means that these modules are distributed
  5646. as part of the GNU system, and @code{packages} identifies modules that
  5647. define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
  5648. Reference Manual}). For instance, the @code{(gnu packages emacs)}
  5649. module exports a variable named @code{emacs}, which is bound to a
  5650. @code{<package>} object (@pxref{Defining Packages}).
  5651. The @code{(gnu packages @dots{})} module name space is
  5652. automatically scanned for packages by the command-line tools. For
  5653. instance, when running @code{guix install emacs}, all the @code{(gnu
  5654. packages @dots{})} modules are scanned until one that exports a package
  5655. object whose name is @code{emacs} is found. This package search
  5656. facility is implemented in the @code{(gnu packages)} module.
  5657. @cindex customization, of packages
  5658. @cindex package module search path
  5659. Users can store package definitions in modules with different
  5660. names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
  5661. name and module name must match. For instance, the @code{(my-packages
  5662. emacs)} module must be stored in a @file{my-packages/emacs.scm} file
  5663. relative to the load path specified with @option{--load-path} or
  5664. @env{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
  5665. guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
  5666. these package definitions visible to the user interfaces:
  5667. @enumerate
  5668. @item
  5669. By adding the directory containing your package modules to the search path
  5670. with the @code{-L} flag of @command{guix package} and other commands
  5671. (@pxref{Common Build Options}), or by setting the @env{GUIX_PACKAGE_PATH}
  5672. environment variable described below.
  5673. @item
  5674. By defining a @dfn{channel} and configuring @command{guix pull} so that it
  5675. pulls from it. A channel is essentially a Git repository containing package
  5676. modules. @xref{Channels}, for more information on how to define and use
  5677. channels.
  5678. @end enumerate
  5679. @env{GUIX_PACKAGE_PATH} works similarly to other search path variables:
  5680. @defvr {Environment Variable} GUIX_PACKAGE_PATH
  5681. This is a colon-separated list of directories to search for additional
  5682. package modules. Directories listed in this variable take precedence
  5683. over the own modules of the distribution.
  5684. @end defvr
  5685. The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
  5686. each package is built based solely on other packages in the
  5687. distribution. The root of this dependency graph is a small set of
  5688. @dfn{bootstrap binaries}, provided by the @code{(gnu packages
  5689. bootstrap)} module. For more information on bootstrapping,
  5690. @pxref{Bootstrapping}.
  5691. @node Defining Packages
  5692. @section Defining Packages
  5693. The high-level interface to package definitions is implemented in the
  5694. @code{(guix packages)} and @code{(guix build-system)} modules. As an
  5695. example, the package definition, or @dfn{recipe}, for the GNU Hello
  5696. package looks like this:
  5697. @lisp
  5698. (define-module (gnu packages hello)
  5699. #:use-module (guix packages)
  5700. #:use-module (guix download)
  5701. #:use-module (guix build-system gnu)
  5702. #:use-module (guix licenses)
  5703. #:use-module (gnu packages gawk))
  5704. (define-public hello
  5705. (package
  5706. (name "hello")
  5707. (version "2.10")
  5708. (source (origin
  5709. (method url-fetch)
  5710. (uri (string-append "mirror://gnu/hello/hello-" version
  5711. ".tar.gz"))
  5712. (sha256
  5713. (base32
  5714. "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
  5715. (build-system gnu-build-system)
  5716. (arguments '(#:configure-flags '("--enable-silent-rules")))
  5717. (inputs (list gawk))
  5718. (synopsis "Hello, GNU world: An example GNU package")
  5719. (description "Guess what GNU Hello prints!")
  5720. (home-page "https://www.gnu.org/software/hello/")
  5721. (license gpl3+)))
  5722. @end lisp
  5723. @noindent
  5724. Without being a Scheme expert, the reader may have guessed the meaning
  5725. of the various fields here. This expression binds the variable
  5726. @code{hello} to a @code{<package>} object, which is essentially a record
  5727. (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
  5728. This package object can be inspected using procedures found in the
  5729. @code{(guix packages)} module; for instance, @code{(package-name hello)}
  5730. returns---surprise!---@code{"hello"}.
  5731. With luck, you may be able to import part or all of the definition of
  5732. the package you are interested in from another repository, using the
  5733. @code{guix import} command (@pxref{Invoking guix import}).
  5734. In the example above, @code{hello} is defined in a module of its own,
  5735. @code{(gnu packages hello)}. Technically, this is not strictly
  5736. necessary, but it is convenient to do so: all the packages defined in
  5737. modules under @code{(gnu packages @dots{})} are automatically known to
  5738. the command-line tools (@pxref{Package Modules}).
  5739. There are a few points worth noting in the above package definition:
  5740. @itemize
  5741. @item
  5742. The @code{source} field of the package is an @code{<origin>} object
  5743. (@pxref{origin Reference}, for the complete reference).
  5744. Here, the @code{url-fetch} method from @code{(guix download)} is used,
  5745. meaning that the source is a file to be downloaded over FTP or HTTP.
  5746. The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
  5747. the GNU mirrors defined in @code{(guix download)}.
  5748. The @code{sha256} field specifies the expected SHA256 hash of the file
  5749. being downloaded. It is mandatory, and allows Guix to check the
  5750. integrity of the file. The @code{(base32 @dots{})} form introduces the
  5751. base32 representation of the hash. You can obtain this information with
  5752. @code{guix download} (@pxref{Invoking guix download}) and @code{guix
  5753. hash} (@pxref{Invoking guix hash}).
  5754. @cindex patches
  5755. When needed, the @code{origin} form can also have a @code{patches} field
  5756. listing patches to be applied, and a @code{snippet} field giving a
  5757. Scheme expression to modify the source code.
  5758. @item
  5759. @cindex GNU Build System
  5760. The @code{build-system} field specifies the procedure to build the
  5761. package (@pxref{Build Systems}). Here, @code{gnu-build-system}
  5762. represents the familiar GNU Build System, where packages may be
  5763. configured, built, and installed with the usual @code{./configure &&
  5764. make && make check && make install} command sequence.
  5765. When you start packaging non-trivial software, you may need tools to
  5766. manipulate those build phases, manipulate files, and so on. @xref{Build
  5767. Utilities}, for more on this.
  5768. @item
  5769. The @code{arguments} field specifies options for the build system
  5770. (@pxref{Build Systems}). Here it is interpreted by
  5771. @code{gnu-build-system} as a request run @file{configure} with the
  5772. @option{--enable-silent-rules} flag.
  5773. @cindex quote
  5774. @cindex quoting
  5775. @findex '
  5776. @findex quote
  5777. @cindex backquote (quasiquote)
  5778. @findex `
  5779. @findex quasiquote
  5780. @cindex comma (unquote)
  5781. @findex ,
  5782. @findex unquote
  5783. What about these quote (@code{'}) characters? They are Scheme syntax to
  5784. introduce a literal list; @code{'} is synonymous with @code{quote}.
  5785. Sometimes you'll also see @code{`} (a backquote, synonymous with
  5786. @code{quasiquote}) and @code{,} (a comma, synonymous with @code{unquote}).
  5787. @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
  5788. for details. Here the value of the @code{arguments} field is a list of
  5789. arguments passed to the build system down the road, as with @code{apply}
  5790. (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
  5791. Manual}).
  5792. The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
  5793. (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
  5794. @code{#:configure-flags} is a keyword used to pass a keyword argument
  5795. to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
  5796. Reference Manual}).
  5797. @item
  5798. The @code{inputs} field specifies inputs to the build process---i.e.,
  5799. build-time or run-time dependencies of the package. Here, we add
  5800. an input, a reference to the @code{gawk}
  5801. variable; @code{gawk} is itself bound to a @code{<package>} object.
  5802. Note that GCC, Coreutils, Bash, and other essential tools do not need to
  5803. be specified as inputs here. Instead, @code{gnu-build-system} takes care
  5804. of ensuring that they are present (@pxref{Build Systems}).
  5805. However, any other dependencies need to be specified in the
  5806. @code{inputs} field. Any dependency not specified here will simply be
  5807. unavailable to the build process, possibly leading to a build failure.
  5808. @end itemize
  5809. @xref{package Reference}, for a full description of possible fields.
  5810. Once a package definition is in place, the
  5811. package may actually be built using the @code{guix build} command-line
  5812. tool (@pxref{Invoking guix build}), troubleshooting any build failures
  5813. you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
  5814. package definition using the @command{guix edit} command
  5815. (@pxref{Invoking guix edit}).
  5816. @xref{Packaging Guidelines}, for
  5817. more information on how to test package definitions, and
  5818. @ref{Invoking guix lint}, for information on how to check a definition
  5819. for style conformance.
  5820. @vindex GUIX_PACKAGE_PATH
  5821. Lastly, @pxref{Channels}, for information
  5822. on how to extend the distribution by adding your own package definitions
  5823. in a ``channel''.
  5824. Finally, updating the package definition to a new upstream version
  5825. can be partly automated by the @command{guix refresh} command
  5826. (@pxref{Invoking guix refresh}).
  5827. Behind the scenes, a derivation corresponding to the @code{<package>}
  5828. object is first computed by the @code{package-derivation} procedure.
  5829. That derivation is stored in a @file{.drv} file under @file{/gnu/store}.
  5830. The build actions it prescribes may then be realized by using the
  5831. @code{build-derivations} procedure (@pxref{The Store}).
  5832. @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
  5833. Return the @code{<derivation>} object of @var{package} for @var{system}
  5834. (@pxref{Derivations}).
  5835. @var{package} must be a valid @code{<package>} object, and @var{system}
  5836. must be a string denoting the target system type---e.g.,
  5837. @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
  5838. must be a connection to the daemon, which operates on the store
  5839. (@pxref{The Store}).
  5840. @end deffn
  5841. @noindent
  5842. @cindex cross-compilation
  5843. Similarly, it is possible to compute a derivation that cross-builds a
  5844. package for some other system:
  5845. @deffn {Scheme Procedure} package-cross-derivation @var{store} @
  5846. @var{package} @var{target} [@var{system}]
  5847. Return the @code{<derivation>} object of @var{package} cross-built from
  5848. @var{system} to @var{target}.
  5849. @var{target} must be a valid GNU triplet denoting the target hardware
  5850. and operating system, such as @code{"aarch64-linux-gnu"}
  5851. (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
  5852. @end deffn
  5853. Once you have package definitions, you can easily define @emph{variants}
  5854. of those packages. @xref{Defining Package Variants}, for more on that.
  5855. @menu
  5856. * package Reference:: The package data type.
  5857. * origin Reference:: The origin data type.
  5858. @end menu
  5859. @node package Reference
  5860. @subsection @code{package} Reference
  5861. This section summarizes all the options available in @code{package}
  5862. declarations (@pxref{Defining Packages}).
  5863. @deftp {Data Type} package
  5864. This is the data type representing a package recipe.
  5865. @table @asis
  5866. @item @code{name}
  5867. The name of the package, as a string.
  5868. @item @code{version}
  5869. The version of the package, as a string. @xref{Version Numbers}, for
  5870. guidelines.
  5871. @item @code{source}
  5872. An object telling how the source code for the package should be
  5873. acquired. Most of the time, this is an @code{origin} object, which
  5874. denotes a file fetched from the Internet (@pxref{origin Reference}). It
  5875. can also be any other ``file-like'' object such as a @code{local-file},
  5876. which denotes a file from the local file system (@pxref{G-Expressions,
  5877. @code{local-file}}).
  5878. @item @code{build-system}
  5879. The build system that should be used to build the package (@pxref{Build
  5880. Systems}).
  5881. @item @code{arguments} (default: @code{'()})
  5882. The arguments that should be passed to the build system. This is a
  5883. list, typically containing sequential keyword-value pairs.
  5884. @item @code{inputs} (default: @code{'()})
  5885. @itemx @code{native-inputs} (default: @code{'()})
  5886. @itemx @code{propagated-inputs} (default: @code{'()})
  5887. @cindex inputs, of packages
  5888. These fields list dependencies of the package. Each element of these
  5889. lists is either a package, origin, or other ``file-like object''
  5890. (@pxref{G-Expressions}); to specify the output of that file-like object
  5891. that should be used, pass a two-element list where the second element is
  5892. the output (@pxref{Packages with Multiple Outputs}, for more on package
  5893. outputs). For example, the list below specifies three inputs:
  5894. @lisp
  5895. (list libffi libunistring
  5896. `(,glib "bin")) ;the "bin" output of GLib
  5897. @end lisp
  5898. In the example above, the @code{"out"} output of @code{libffi} and
  5899. @code{libunistring} is used.
  5900. @quotation Compatibility Note
  5901. Until version 1.3.0, input lists were a list of tuples,
  5902. where each tuple has a label for the input (a string) as its
  5903. first element, a package, origin, or derivation as its second element,
  5904. and optionally the name of the output thereof that should be used, which
  5905. defaults to @code{"out"}. For example, the list below is equivalent to
  5906. the one above, but using the @dfn{old input style}:
  5907. @lisp
  5908. ;; Old input style (deprecated).
  5909. `(("libffi" ,libffi)
  5910. ("libunistring" ,libunistring)
  5911. ("glib:bin" ,glib "bin")) ;the "bin" output of GLib
  5912. @end lisp
  5913. This style is now deprecated; it is still supported but support will be
  5914. removed in a future version. It should not be used for new package
  5915. definitions. @xref{Invoking guix style}, on how to migrate to the new
  5916. style.
  5917. @end quotation
  5918. @cindex cross compilation, package dependencies
  5919. The distinction between @code{native-inputs} and @code{inputs} is
  5920. necessary when considering cross-compilation. When cross-compiling,
  5921. dependencies listed in @code{inputs} are built for the @emph{target}
  5922. architecture; conversely, dependencies listed in @code{native-inputs}
  5923. are built for the architecture of the @emph{build} machine.
  5924. @code{native-inputs} is typically used to list tools needed at
  5925. build time, but not at run time, such as Autoconf, Automake, pkg-config,
  5926. Gettext, or Bison. @command{guix lint} can report likely mistakes in
  5927. this area (@pxref{Invoking guix lint}).
  5928. @anchor{package-propagated-inputs}
  5929. Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
  5930. specified packages will be automatically installed to profiles
  5931. (@pxref{Features, the role of profiles in Guix}) alongside the package
  5932. they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
  5933. package}}, for information on how @command{guix package} deals with
  5934. propagated inputs).
  5935. For example this is necessary when packaging a C/C++ library that needs
  5936. headers of another library to compile, or when a pkg-config file refers
  5937. to another one @i{via} its @code{Requires} field.
  5938. Another example where @code{propagated-inputs} is useful is for languages
  5939. that lack a facility to record the run-time search path akin to the
  5940. @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
  5941. more. When packaging libraries written in those languages, ensure they
  5942. can find library code they depend on at run time by listing run-time
  5943. dependencies in @code{propagated-inputs} rather than @code{inputs}.
  5944. @item @code{outputs} (default: @code{'("out")})
  5945. The list of output names of the package. @xref{Packages with Multiple
  5946. Outputs}, for typical uses of additional outputs.
  5947. @item @code{native-search-paths} (default: @code{'()})
  5948. @itemx @code{search-paths} (default: @code{'()})
  5949. A list of @code{search-path-specification} objects describing
  5950. search-path environment variables honored by the package. @xref{Search
  5951. Paths}, for more on search path specifications.
  5952. As for inputs, the distinction between @code{native-search-paths} and
  5953. @code{search-paths} only matters when cross-compiling. In a
  5954. cross-compilation context, @code{native-search-paths} applies
  5955. exclusively to native inputs whereas @code{search-paths} applies only to
  5956. host inputs.
  5957. Packages such as cross-compilers care about target inputs---for
  5958. instance, our (modified) GCC cross-compiler has
  5959. @env{CROSS_C_INCLUDE_PATH} in @code{search-paths}, which allows it to
  5960. pick @file{.h} files for the target system and @emph{not} those of
  5961. native inputs. For the majority of packages though, only
  5962. @code{native-search-paths} makes sense.
  5963. @item @code{replacement} (default: @code{#f})
  5964. This must be either @code{#f} or a package object that will be used as a
  5965. @dfn{replacement} for this package. @xref{Security Updates, grafts},
  5966. for details.
  5967. @item @code{synopsis}
  5968. A one-line description of the package.
  5969. @item @code{description}
  5970. A more elaborate description of the package, as a string in Texinfo
  5971. syntax.
  5972. @item @code{license}
  5973. @cindex license, of packages
  5974. The license of the package; a value from @code{(guix licenses)},
  5975. or a list of such values.
  5976. @item @code{home-page}
  5977. The URL to the home-page of the package, as a string.
  5978. @item @code{supported-systems} (default: @code{%supported-systems})
  5979. The list of systems supported by the package, as strings of the form
  5980. @code{architecture-kernel}, for example @code{"x86_64-linux"}.
  5981. @item @code{location} (default: source location of the @code{package} form)
  5982. The source location of the package. It is useful to override this when
  5983. inheriting from another package, in which case this field is not
  5984. automatically corrected.
  5985. @end table
  5986. @end deftp
  5987. @deffn {Scheme Syntax} this-package
  5988. When used in the @emph{lexical scope} of a package field definition, this
  5989. identifier resolves to the package being defined.
  5990. The example below shows how to add a package as a native input of itself when
  5991. cross-compiling:
  5992. @lisp
  5993. (package
  5994. (name "guile")
  5995. ;; ...
  5996. ;; When cross-compiled, Guile, for example, depends on
  5997. ;; a native version of itself. Add it here.
  5998. (native-inputs (if (%current-target-system)
  5999. (list this-package)
  6000. '())))
  6001. @end lisp
  6002. It is an error to refer to @code{this-package} outside a package definition.
  6003. @end deffn
  6004. The following helper procedures are provided to help deal with package
  6005. inputs.
  6006. @deffn {Scheme Procedure} lookup-package-input @var{package} @var{name}
  6007. @deffnx {Scheme Procedure} lookup-package-native-input @var{package} @var{name}
  6008. @deffnx {Scheme Procedure} lookup-package-propagated-input @var{package} @var{name}
  6009. @deffnx {Scheme Procedure} lookup-package-direct-input @var{package} @var{name}
  6010. Look up @var{name} among @var{package}'s inputs (or native, propagated,
  6011. or direct inputs). Return it if found, @code{#f} otherwise.
  6012. @var{name} is the name of a package depended on. Here's how you might
  6013. use it:
  6014. @lisp
  6015. (use-modules (guix packages) (gnu packages base))
  6016. (lookup-package-direct-input coreutils "gmp")
  6017. @result{} #<package gmp@@6.2.1 @dots{}>
  6018. @end lisp
  6019. In this example we obtain the @code{gmp} package that is among the
  6020. direct inputs of @code{coreutils}.
  6021. @end deffn
  6022. @cindex development inputs, of a package
  6023. @cindex implicit inputs, of a package
  6024. Sometimes you will want to obtain the list of inputs needed to
  6025. @emph{develop} a package---all the inputs that are visible when the
  6026. package is compiled. This is what the @code{package-development-inputs}
  6027. procedure returns.
  6028. @deffn {Scheme Procedure} package-development-inputs @var{package} @
  6029. [@var{system}] [#:target #f]
  6030. Return the list of inputs required by @var{package} for development
  6031. purposes on @var{system}. When @var{target} is true, return the inputs
  6032. needed to cross-compile @var{package} from @var{system} to
  6033. @var{triplet}, where @var{triplet} is a triplet such as
  6034. @code{"aarch64-linux-gnu"}.
  6035. Note that the result includes both explicit inputs and implicit
  6036. inputs---inputs automatically added by the build system (@pxref{Build
  6037. Systems}). Let us take the @code{hello} package to illustrate that:
  6038. @lisp
  6039. (use-modules (gnu packages base) (guix packages))
  6040. hello
  6041. @result{} #<package hello@@2.10 gnu/packages/base.scm:79 7f585d4f6790>
  6042. (package-direct-inputs hello)
  6043. @result{} ()
  6044. (package-development-inputs hello)
  6045. @result{} (("source" @dots{}) ("tar" #<package tar@@1.32 @dots{}>) @dots{})
  6046. @end lisp
  6047. In this example, @code{package-direct-inputs} returns the empty list,
  6048. because @code{hello} has zero explicit dependencies. Conversely,
  6049. @code{package-development-inputs} includes inputs implicitly added by
  6050. @code{gnu-build-system} that are required to build @code{hello}: tar,
  6051. gzip, GCC, libc, Bash, and more. To visualize it, @command{guix graph
  6052. hello} would show you explicit inputs, whereas @command{guix graph -t
  6053. bag hello} would include implicit inputs (@pxref{Invoking guix graph}).
  6054. @end deffn
  6055. Because packages are regular Scheme objects that capture a complete
  6056. dependency graph and associated build procedures, it is often useful to
  6057. write procedures that take a package and return a modified version
  6058. thereof according to some parameters. Below are a few examples.
  6059. @cindex tool chain, choosing a package's tool chain
  6060. @deffn {Scheme Procedure} package-with-c-toolchain @var{package} @var{toolchain}
  6061. Return a variant of @var{package} that uses @var{toolchain} instead of
  6062. the default GNU C/C++ toolchain. @var{toolchain} must be a list of
  6063. inputs (label/package tuples) providing equivalent functionality, such
  6064. as the @code{gcc-toolchain} package.
  6065. The example below returns a variant of the @code{hello} package built
  6066. with GCC@tie{}10.x and the rest of the GNU tool chain (Binutils and the
  6067. GNU C Library) instead of the default tool chain:
  6068. @lisp
  6069. (let ((toolchain (specification->package "gcc-toolchain@@10")))
  6070. (package-with-c-toolchain hello `(("toolchain" ,toolchain))))
  6071. @end lisp
  6072. The build tool chain is part of the @dfn{implicit inputs} of
  6073. packages---it's usually not listed as part of the various ``inputs''
  6074. fields and is instead pulled in by the build system. Consequently, this
  6075. procedure works by changing the build system of @var{package} so that it
  6076. pulls in @var{toolchain} instead of the defaults. @ref{Build Systems},
  6077. for more on build systems.
  6078. @end deffn
  6079. @node origin Reference
  6080. @subsection @code{origin} Reference
  6081. This section documents @dfn{origins}. An @code{origin} declaration
  6082. specifies data that must be ``produced''---downloaded, usually---and
  6083. whose content hash is known in advance. Origins are primarily used to
  6084. represent the source code of packages (@pxref{Defining Packages}). For
  6085. that reason, the @code{origin} form allows you to declare patches to
  6086. apply to the original source code as well as code snippets to modify it.
  6087. @deftp {Data Type} origin
  6088. This is the data type representing a source code origin.
  6089. @table @asis
  6090. @item @code{uri}
  6091. An object containing the URI of the source. The object type depends on
  6092. the @code{method} (see below). For example, when using the
  6093. @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
  6094. values are: a URL represented as a string, or a list thereof.
  6095. @cindex fixed-output derivations, for download
  6096. @item @code{method}
  6097. A monadic procedure that handles the given URI@. The procedure must
  6098. accept at least three arguments: the value of the @code{uri} field and
  6099. the hash algorithm and hash value specified by the @code{hash} field.
  6100. It must return a store item or a derivation in the store monad
  6101. (@pxref{The Store Monad}); most methods return a fixed-output derivation
  6102. (@pxref{Derivations}).
  6103. Commonly used methods include @code{url-fetch}, which fetches data from
  6104. a URL, and @code{git-fetch}, which fetches data from a Git repository
  6105. (see below).
  6106. @item @code{sha256}
  6107. A bytevector containing the SHA-256 hash of the source. This is
  6108. equivalent to providing a @code{content-hash} SHA256 object in the
  6109. @code{hash} field described below.
  6110. @item @code{hash}
  6111. The @code{content-hash} object of the source---see below for how to use
  6112. @code{content-hash}.
  6113. You can obtain this information using @code{guix download}
  6114. (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
  6115. guix hash}).
  6116. @item @code{file-name} (default: @code{#f})
  6117. The file name under which the source code should be saved. When this is
  6118. @code{#f}, a sensible default value will be used in most cases. In case
  6119. the source is fetched from a URL, the file name from the URL will be
  6120. used. For version control checkouts, it is recommended to provide the
  6121. file name explicitly because the default is not very descriptive.
  6122. @item @code{patches} (default: @code{'()})
  6123. A list of file names, origins, or file-like objects (@pxref{G-Expressions,
  6124. file-like objects}) pointing to patches to be applied to the source.
  6125. This list of patches must be unconditional. In particular, it cannot
  6126. depend on the value of @code{%current-system} or
  6127. @code{%current-target-system}.
  6128. @item @code{snippet} (default: @code{#f})
  6129. A G-expression (@pxref{G-Expressions}) or S-expression that will be run
  6130. in the source directory. This is a convenient way to modify the source,
  6131. sometimes more convenient than a patch.
  6132. @item @code{patch-flags} (default: @code{'("-p1")})
  6133. A list of command-line flags that should be passed to the @code{patch}
  6134. command.
  6135. @item @code{patch-inputs} (default: @code{#f})
  6136. Input packages or derivations to the patching process. When this is
  6137. @code{#f}, the usual set of inputs necessary for patching are provided,
  6138. such as GNU@tie{}Patch.
  6139. @item @code{modules} (default: @code{'()})
  6140. A list of Guile modules that should be loaded during the patching
  6141. process and while running the code in the @code{snippet} field.
  6142. @item @code{patch-guile} (default: @code{#f})
  6143. The Guile package that should be used in the patching process. When
  6144. this is @code{#f}, a sensible default is used.
  6145. @end table
  6146. @end deftp
  6147. @deftp {Data Type} content-hash @var{value} [@var{algorithm}]
  6148. Construct a content hash object for the given @var{algorithm}, and with
  6149. @var{value} as its hash value. When @var{algorithm} is omitted, assume
  6150. it is @code{sha256}.
  6151. @var{value} can be a literal string, in which case it is base32-decoded,
  6152. or it can be a bytevector.
  6153. The following forms are all equivalent:
  6154. @lisp
  6155. (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj")
  6156. (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"
  6157. sha256)
  6158. (content-hash (base32
  6159. "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"))
  6160. (content-hash (base64 "kkb+RPaP7uyMZmu4eXPVkM4BN8yhRd8BTHLslb6f/Rc=")
  6161. sha256)
  6162. @end lisp
  6163. Technically, @code{content-hash} is currently implemented as a macro.
  6164. It performs sanity checks at macro-expansion time, when possible, such
  6165. as ensuring that @var{value} has the right size for @var{algorithm}.
  6166. @end deftp
  6167. As we have seen above, how exactly the data an origin refers to is
  6168. retrieved is determined by its @code{method} field. The @code{(guix
  6169. download)} module provides the most common method, @code{url-fetch},
  6170. described below.
  6171. @deffn {Scheme Procedure} url-fetch @var{url} @var{hash-algo} @var{hash} @
  6172. [name] [#:executable? #f]
  6173. Return a fixed-output derivation that fetches data from @var{url} (a
  6174. string, or a list of strings denoting alternate URLs), which is expected
  6175. to have hash @var{hash} of type @var{hash-algo} (a symbol). By default,
  6176. the file name is the base name of URL; optionally, @var{name} can
  6177. specify a different file name. When @var{executable?} is true, make the
  6178. downloaded file executable.
  6179. When one of the URL starts with @code{mirror://}, then its host part is
  6180. interpreted as the name of a mirror scheme, taken from @file{%mirror-file}.
  6181. Alternatively, when URL starts with @code{file://}, return the
  6182. corresponding file name in the store.
  6183. @end deffn
  6184. Likewise, the @code{(guix git-download)} module defines the
  6185. @code{git-fetch} origin method, which fetches data from a Git version
  6186. control repository, and the @code{git-reference} data type to describe
  6187. the repository and revision to fetch.
  6188. @deffn {Scheme Procedure} git-fetch @var{ref} @var{hash-algo} @var{hash}
  6189. Return a fixed-output derivation that fetches @var{ref}, a
  6190. @code{<git-reference>} object. The output is expected to have recursive
  6191. hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
  6192. the file name, or a generic name if @code{#f}.
  6193. @end deffn
  6194. @deftp {Data Type} git-reference
  6195. This data type represents a Git reference for @code{git-fetch} to
  6196. retrieve.
  6197. @table @asis
  6198. @item @code{url}
  6199. The URL of the Git repository to clone.
  6200. @item @code{commit}
  6201. This string denotes either the commit to fetch (a hexadecimal string),
  6202. or the tag to fetch. You can also use a ``short'' commit ID or a
  6203. @command{git describe} style identifier such as
  6204. @code{v1.0.1-10-g58d7909c97}.
  6205. @item @code{recursive?} (default: @code{#f})
  6206. This Boolean indicates whether to recursively fetch Git sub-modules.
  6207. @end table
  6208. The example below denotes the @code{v2.10} tag of the GNU@tie{}Hello
  6209. repository:
  6210. @lisp
  6211. (git-reference
  6212. (url "https://git.savannah.gnu.org/git/hello.git")
  6213. (commit "v2.10"))
  6214. @end lisp
  6215. This is equivalent to the reference below, which explicitly names the
  6216. commit:
  6217. @lisp
  6218. (git-reference
  6219. (url "https://git.savannah.gnu.org/git/hello.git")
  6220. (commit "dc7dc56a00e48fe6f231a58f6537139fe2908fb9"))
  6221. @end lisp
  6222. @end deftp
  6223. For Mercurial repositories, the module @code{(guix hg-download)} defines
  6224. the @code{hg-fetch} origin method and @code{hg-reference} data type for
  6225. support of the Mercurial version control system.
  6226. @deffn {Scheme Procedure} hg-fetch @var{ref} @var{hash-algo} @var{hash} @
  6227. [name]
  6228. Return a fixed-output derivation that fetches @var{ref}, a
  6229. @code{<hg-reference>} object. The output is expected to have recursive
  6230. hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
  6231. the file name, or a generic name if @code{#false}.
  6232. @end deffn
  6233. @node Defining Package Variants
  6234. @section Defining Package Variants
  6235. @cindex customizing packages
  6236. @cindex variants, of packages
  6237. One of the nice things with Guix is that, given a package definition,
  6238. you can easily @emph{derive} variants of that package---for a different
  6239. upstream version, with different dependencies, different compilation
  6240. options, and so on. Some of these custom packages can be defined
  6241. straight from the command line (@pxref{Package Transformation Options}).
  6242. This section describes how to define package variants in code. This can
  6243. be useful in ``manifests'' (@pxref{profile-manifest,
  6244. @option{--manifest}}) and in your own package collection
  6245. (@pxref{Creating a Channel}), among others!
  6246. @cindex inherit, for package definitions
  6247. As discussed earlier, packages are first-class objects in the Scheme
  6248. language. The @code{(guix packages)} module provides the @code{package}
  6249. construct to define new package objects (@pxref{package Reference}).
  6250. The easiest way to define a package variant is using the @code{inherit}
  6251. keyword together with @code{package}. This allows you to inherit from a
  6252. package definition while overriding the fields you want.
  6253. For example, given the @code{hello} variable, which contains a
  6254. definition for the current version of GNU@tie{}Hello, here's how you
  6255. would define a variant for version 2.2 (released in 2006, it's
  6256. vintage!):
  6257. @lisp
  6258. (use-modules (gnu packages base)) ;for 'hello'
  6259. (define hello-2.2
  6260. (package
  6261. (inherit hello)
  6262. (version "2.2")
  6263. (source (origin
  6264. (method url-fetch)
  6265. (uri (string-append "mirror://gnu/hello/hello-" version
  6266. ".tar.gz"))
  6267. (sha256
  6268. (base32
  6269. "0lappv4slgb5spyqbh6yl5r013zv72yqg2pcl30mginf3wdqd8k9"))))))
  6270. @end lisp
  6271. The example above corresponds to what the @option{--with-source} package
  6272. transformation option does. Essentially @code{hello-2.2} preserves all
  6273. the fields of @code{hello}, except @code{version} and @code{source},
  6274. which it overrides. Note that the original @code{hello} variable is
  6275. still there, in the @code{(gnu packages base)} module, unchanged. When
  6276. you define a custom package like this, you are really @emph{adding} a
  6277. new package definition; the original one remains available.
  6278. You can just as well define variants with a different set of
  6279. dependencies than the original package. For example, the default
  6280. @code{gdb} package depends on @code{guile}, but since that is an
  6281. optional dependency, you can define a variant that removes that
  6282. dependency like so:
  6283. @lisp
  6284. (use-modules (gnu packages gdb)) ;for 'gdb'
  6285. (define gdb-sans-guile
  6286. (package
  6287. (inherit gdb)
  6288. (inputs (modify-inputs (package-inputs gdb)
  6289. (delete "guile")))))
  6290. @end lisp
  6291. The @code{modify-inputs} form above removes the @code{"guile"} package
  6292. from the @code{inputs} field of @code{gdb}. The @code{modify-inputs}
  6293. macro is a helper that can prove useful anytime you want to remove, add,
  6294. or replace package inputs.
  6295. @deffn {Scheme Syntax} modify-inputs @var{inputs} @var{clauses}
  6296. Modify the given package inputs, as returned by @code{package-inputs} & co.,
  6297. according to the given clauses. Each clause must have one of the
  6298. following forms:
  6299. @table @code
  6300. @item (delete @var{name}@dots{})
  6301. Delete from the inputs packages with the given @var{name}s (strings).
  6302. @item (append @var{package}@dots{})
  6303. Add @var{package}s to the end of the input list.
  6304. @item (prepend @var{package}@dots{})
  6305. Add @var{package}s to the front of the input list.
  6306. @end table
  6307. The example below removes the GMP and ACL inputs of Coreutils and adds
  6308. libcap to the back of the input list:
  6309. @lisp
  6310. (modify-inputs (package-inputs coreutils)
  6311. (delete "gmp" "acl")
  6312. (append libcap))
  6313. @end lisp
  6314. The example below replaces the @code{guile} package from the inputs of
  6315. @code{guile-redis} with @code{guile-2.2}:
  6316. @lisp
  6317. (modify-inputs (package-inputs guile-redis)
  6318. (replace "guile" guile-2.2))
  6319. @end lisp
  6320. The last type of clause is @code{prepend}, to add inputs to the front of
  6321. the list.
  6322. @end deffn
  6323. In some cases, you may find it useful to write functions
  6324. (``procedures'', in Scheme parlance) that return a package based on some
  6325. parameters. For example, consider the @code{luasocket} library for the
  6326. Lua programming language. We want to create @code{luasocket} packages
  6327. for major versions of Lua. One way to do that is to define a procedure
  6328. that takes a Lua package and returns a @code{luasocket} package that
  6329. depends on it:
  6330. @lisp
  6331. (define (make-lua-socket name lua)
  6332. ;; Return a luasocket package built with LUA.
  6333. (package
  6334. (name name)
  6335. (version "3.0")
  6336. ;; several fields omitted
  6337. (inputs (list lua))
  6338. (synopsis "Socket library for Lua")))
  6339. (define-public lua5.1-socket
  6340. (make-lua-socket "lua5.1-socket" lua-5.1))
  6341. (define-public lua5.2-socket
  6342. (make-lua-socket "lua5.2-socket" lua-5.2))
  6343. @end lisp
  6344. Here we have defined packages @code{lua5.1-socket} and
  6345. @code{lua5.2-socket} by calling @code{make-lua-socket} with different
  6346. arguments. @xref{Procedures,,, guile, GNU Guile Reference Manual}, for
  6347. more info on procedures. Having top-level public definitions for these
  6348. two packages means that they can be referred to from the command line
  6349. (@pxref{Package Modules}).
  6350. @cindex package transformations
  6351. These are pretty simple package variants. As a convenience, the
  6352. @code{(guix transformations)} module provides a high-level interface
  6353. that directly maps to the more sophisticated package transformation
  6354. options (@pxref{Package Transformation Options}):
  6355. @deffn {Scheme Procedure} options->transformation @var{opts}
  6356. Return a procedure that, when passed an object to build (package,
  6357. derivation, etc.), applies the transformations specified by @var{opts} and returns
  6358. the resulting objects. @var{opts} must be a list of symbol/string pairs such as:
  6359. @lisp
  6360. ((with-branch . "guile-gcrypt=master")
  6361. (without-tests . "libgcrypt"))
  6362. @end lisp
  6363. Each symbol names a transformation and the corresponding string is an argument
  6364. to that transformation.
  6365. @end deffn
  6366. For instance, a manifest equivalent to this command:
  6367. @example
  6368. guix build guix \
  6369. --with-branch=guile-gcrypt=master \
  6370. --with-debug-info=zlib
  6371. @end example
  6372. @noindent
  6373. ... would look like this:
  6374. @lisp
  6375. (use-modules (guix transformations))
  6376. (define transform
  6377. ;; The package transformation procedure.
  6378. (options->transformation
  6379. '((with-branch . "guile-gcrypt=master")
  6380. (with-debug-info . "zlib"))))
  6381. (packages->manifest
  6382. (list (transform (specification->package "guix"))))
  6383. @end lisp
  6384. @cindex input rewriting
  6385. @cindex dependency graph rewriting
  6386. The @code{options->transformation} procedure is convenient, but it's
  6387. perhaps also not as flexible as you may like. How is it implemented?
  6388. The astute reader probably noticed that most package transformation
  6389. options go beyond the superficial changes shown in the first examples of
  6390. this section: they involve @dfn{input rewriting}, whereby the dependency
  6391. graph of a package is rewritten by replacing specific inputs by others.
  6392. Dependency graph rewriting, for the purposes of swapping packages in the
  6393. graph, is what the @code{package-input-rewriting} procedure in
  6394. @code{(guix packages)} implements.
  6395. @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
  6396. [@var{rewrite-name}] [#:deep? #t]
  6397. Return a procedure that, when passed a package, replaces its direct and
  6398. indirect dependencies, including implicit inputs when @var{deep?} is
  6399. true, according to @var{replacements}. @var{replacements} is a list of
  6400. package pairs; the first element of each pair is the package to replace,
  6401. and the second one is the replacement.
  6402. Optionally, @var{rewrite-name} is a one-argument procedure that takes
  6403. the name of a package and returns its new name after rewrite.
  6404. @end deffn
  6405. @noindent
  6406. Consider this example:
  6407. @lisp
  6408. (define libressl-instead-of-openssl
  6409. ;; This is a procedure to replace OPENSSL by LIBRESSL,
  6410. ;; recursively.
  6411. (package-input-rewriting `((,openssl . ,libressl))))
  6412. (define git-with-libressl
  6413. (libressl-instead-of-openssl git))
  6414. @end lisp
  6415. @noindent
  6416. Here we first define a rewriting procedure that replaces @var{openssl}
  6417. with @var{libressl}. Then we use it to define a @dfn{variant} of the
  6418. @var{git} package that uses @var{libressl} instead of @var{openssl}.
  6419. This is exactly what the @option{--with-input} command-line option does
  6420. (@pxref{Package Transformation Options, @option{--with-input}}).
  6421. The following variant of @code{package-input-rewriting} can match packages to
  6422. be replaced by name rather than by identity.
  6423. @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements} [#:deep? #t]
  6424. Return a procedure that, given a package, applies the given
  6425. @var{replacements} to all the package graph, including implicit inputs
  6426. unless @var{deep?} is false. @var{replacements} is a list of
  6427. spec/procedures pair; each spec is a package specification such as
  6428. @code{"gcc"} or @code{"guile@@2"}, and each procedure takes a matching
  6429. package and returns a replacement for that package.
  6430. @end deffn
  6431. The example above could be rewritten this way:
  6432. @lisp
  6433. (define libressl-instead-of-openssl
  6434. ;; Replace all the packages called "openssl" with LibreSSL.
  6435. (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
  6436. @end lisp
  6437. The key difference here is that, this time, packages are matched by spec and
  6438. not by identity. In other words, any package in the graph that is called
  6439. @code{openssl} will be replaced.
  6440. A more generic procedure to rewrite a package dependency graph is
  6441. @code{package-mapping}: it supports arbitrary changes to nodes in the
  6442. graph.
  6443. @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}] [#:deep? #f]
  6444. Return a procedure that, given a package, applies @var{proc} to all the packages
  6445. depended on and returns the resulting package. The procedure stops recursion
  6446. when @var{cut?} returns true for a given package. When @var{deep?} is true, @var{proc} is
  6447. applied to implicit inputs as well.
  6448. @end deffn
  6449. @node Build Systems
  6450. @section Build Systems
  6451. @cindex build system
  6452. Each package definition specifies a @dfn{build system} and arguments for
  6453. that build system (@pxref{Defining Packages}). This @code{build-system}
  6454. field represents the build procedure of the package, as well as implicit
  6455. dependencies of that build procedure.
  6456. Build systems are @code{<build-system>} objects. The interface to
  6457. create and manipulate them is provided by the @code{(guix build-system)}
  6458. module, and actual build systems are exported by specific modules.
  6459. @cindex bag (low-level package representation)
  6460. Under the hood, build systems first compile package objects to
  6461. @dfn{bags}. A @dfn{bag} is like a package, but with less
  6462. ornamentation---in other words, a bag is a lower-level representation of
  6463. a package, which includes all the inputs of that package, including some
  6464. that were implicitly added by the build system. This intermediate
  6465. representation is then compiled to a derivation (@pxref{Derivations}).
  6466. The @code{package-with-c-toolchain} is an example of a way to change the
  6467. implicit inputs that a package's build system pulls in (@pxref{package
  6468. Reference, @code{package-with-c-toolchain}}).
  6469. Build systems accept an optional list of @dfn{arguments}. In package
  6470. definitions, these are passed @i{via} the @code{arguments} field
  6471. (@pxref{Defining Packages}). They are typically keyword arguments
  6472. (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
  6473. Guile Reference Manual}). The value of these arguments is usually
  6474. evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
  6475. by the daemon (@pxref{Derivations}).
  6476. The main build system is @code{gnu-build-system}, which implements the
  6477. standard build procedure for GNU and many other packages. It
  6478. is provided by the @code{(guix build-system gnu)} module.
  6479. @defvr {Scheme Variable} gnu-build-system
  6480. @code{gnu-build-system} represents the GNU Build System, and variants
  6481. thereof (@pxref{Configuration, configuration and makefile conventions,,
  6482. standards, GNU Coding Standards}).
  6483. @cindex build phases
  6484. In a nutshell, packages using it are configured, built, and installed with
  6485. the usual @code{./configure && make && make check && make install}
  6486. command sequence. In practice, a few additional steps are often needed.
  6487. All these steps are split up in separate @dfn{phases}.
  6488. @xref{Build Phases}, for more info on build phases and ways to customize
  6489. them.
  6490. In addition, this build system ensures that the ``standard'' environment
  6491. for GNU packages is available. This includes tools such as GCC, libc,
  6492. Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
  6493. build-system gnu)} module for a complete list). We call these the
  6494. @dfn{implicit inputs} of a package, because package definitions do not
  6495. have to mention them.
  6496. This build system supports a number of keyword arguments, which can be
  6497. passed @i{via} the @code{arguments} field of a package. Here are some
  6498. of the main parameters:
  6499. @table @code
  6500. @item #:phases
  6501. This argument specifies build-side code that evaluates to an alist of
  6502. build phases. @xref{Build Phases}, for more information.
  6503. @item #:configure-flags
  6504. This is a list of flags (strings) passed to the @command{configure}
  6505. script. @xref{Defining Packages}, for an example.
  6506. @item #:make-flags
  6507. This list of strings contains flags passed as arguments to
  6508. @command{make} invocations in the @code{build}, @code{check}, and
  6509. @code{install} phases.
  6510. @item #:out-of-source?
  6511. This Boolean, @code{#f} by default, indicates whether to run builds in a
  6512. build directory separate from the source tree.
  6513. When it is true, the @code{configure} phase creates a separate build
  6514. directory, changes to that directory, and runs the @code{configure}
  6515. script from there. This is useful for packages that require it, such as
  6516. @code{glibc}.
  6517. @item #:tests?
  6518. This Boolean, @code{#t} by default, indicates whether the @code{check}
  6519. phase should run the package's test suite.
  6520. @item #:test-target
  6521. This string, @code{"check"} by default, gives the name of the makefile
  6522. target used by the @code{check} phase.
  6523. @item #:parallel-build?
  6524. @itemx #:parallel-tests?
  6525. These Boolean values specify whether to build, respectively run the test
  6526. suite, in parallel, with the @code{-j} flag of @command{make}. When
  6527. they are true, @code{make} is passed @code{-j@var{n}}, where @var{n} is
  6528. the number specified as the @option{--cores} option of
  6529. @command{guix-daemon} or that of the @command{guix} client command
  6530. (@pxref{Common Build Options, @option{--cores}}).
  6531. @cindex RUNPATH, validation
  6532. @item #:validate-runpath?
  6533. This Boolean, @code{#t} by default, determines whether to ``validate''
  6534. the @code{RUNPATH} of ELF binaries (@code{.so} shared libraries as well
  6535. as executables) previously installed by the @code{install} phase.
  6536. This validation step consists in making sure that all the shared
  6537. libraries needed by an ELF binary, which are listed as
  6538. @code{DT_NEEDED} entries in its @code{PT_DYNAMIC} segment, appear in the
  6539. @code{DT_RUNPATH} entry of that binary. In other words, it ensures that
  6540. running or using those binaries will not result in a ``file not found''
  6541. error at run time. @xref{Options, @option{-rpath},, ld, The GNU
  6542. Linker}, for more information on @code{RUNPATH}.
  6543. @item #:substitutable?
  6544. This Boolean, @code{#t} by default, tells whether the package outputs
  6545. should be substitutable---i.e., whether users should be able to obtain
  6546. substitutes for them instead of building locally (@pxref{Substitutes}).
  6547. @item #:allowed-references
  6548. @itemx #:disallowed-references
  6549. When true, these arguments must be a list of dependencies that must not
  6550. appear among the references of the build results. If, upon build
  6551. completion, some of these references are retained, the build process
  6552. fails.
  6553. This is useful to ensure that a package does not erroneously keep a
  6554. reference to some of it build-time inputs, in cases where doing so
  6555. would, for example, unnecessarily increase its size (@pxref{Invoking
  6556. guix size}).
  6557. @end table
  6558. Most other build systems support these keyword arguments.
  6559. @end defvr
  6560. Other @code{<build-system>} objects are defined to support other
  6561. conventions and tools used by free software packages. They inherit most
  6562. of @code{gnu-build-system}, and differ mainly in the set of inputs
  6563. implicitly added to the build process, and in the list of phases
  6564. executed. Some of these build systems are listed below.
  6565. @defvr {Scheme Variable} ant-build-system
  6566. This variable is exported by @code{(guix build-system ant)}. It
  6567. implements the build procedure for Java packages that can be built with
  6568. @url{https://ant.apache.org/, Ant build tool}.
  6569. It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
  6570. provided by the @code{icedtea} package to the set of inputs. Different
  6571. packages can be specified with the @code{#:ant} and @code{#:jdk}
  6572. parameters, respectively.
  6573. When the original package does not provide a suitable Ant build file,
  6574. the parameter @code{#:jar-name} can be used to generate a minimal Ant
  6575. build file @file{build.xml} with tasks to build the specified jar
  6576. archive. In this case the parameter @code{#:source-dir} can be used to
  6577. specify the source sub-directory, defaulting to ``src''.
  6578. The @code{#:main-class} parameter can be used with the minimal ant
  6579. buildfile to specify the main class of the resulting jar. This makes the
  6580. jar file executable. The @code{#:test-include} parameter can be used to
  6581. specify the list of junit tests to run. It defaults to
  6582. @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
  6583. disable some tests. It defaults to @code{(list "**/Abstract*.java")},
  6584. because abstract classes cannot be run as tests.
  6585. The parameter @code{#:build-target} can be used to specify the Ant task
  6586. that should be run during the @code{build} phase. By default the
  6587. ``jar'' task will be run.
  6588. @end defvr
  6589. @defvr {Scheme Variable} android-ndk-build-system
  6590. @cindex Android distribution
  6591. @cindex Android NDK build system
  6592. This variable is exported by @code{(guix build-system android-ndk)}. It
  6593. implements a build procedure for Android NDK (native development kit)
  6594. packages using a Guix-specific build process.
  6595. The build system assumes that packages install their public interface
  6596. (header) files to the subdirectory @file{include} of the @code{out} output and
  6597. their libraries to the subdirectory @file{lib} the @code{out} output.
  6598. It's also assumed that the union of all the dependencies of a package
  6599. has no conflicting files.
  6600. For the time being, cross-compilation is not supported - so right now
  6601. the libraries and header files are assumed to be host tools.
  6602. @end defvr
  6603. @defvr {Scheme Variable} asdf-build-system/source
  6604. @defvrx {Scheme Variable} asdf-build-system/sbcl
  6605. @defvrx {Scheme Variable} asdf-build-system/ecl
  6606. These variables, exported by @code{(guix build-system asdf)}, implement
  6607. build procedures for Common Lisp packages using
  6608. @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
  6609. definition facility for Common Lisp programs and libraries.
  6610. The @code{asdf-build-system/source} system installs the packages in
  6611. source form, and can be loaded using any common lisp implementation, via
  6612. ASDF@. The others, such as @code{asdf-build-system/sbcl}, install binary
  6613. systems in the format which a particular implementation understands.
  6614. These build systems can also be used to produce executable programs, or
  6615. lisp images which contain a set of packages pre-loaded.
  6616. The build system uses naming conventions. For binary packages, the
  6617. package name should be prefixed with the lisp implementation, such as
  6618. @code{sbcl-} for @code{asdf-build-system/sbcl}.
  6619. Additionally, the corresponding source package should be labeled using
  6620. the same convention as python packages (see @ref{Python Modules}), using
  6621. the @code{cl-} prefix.
  6622. In order to create executable programs and images, the build-side
  6623. procedures @code{build-program} and @code{build-image} can be used.
  6624. They should be called in a build phase after the
  6625. @code{create-asdf-configuration} phase, so that the system which was
  6626. just built can be used within the resulting image. @code{build-program}
  6627. requires a list of Common Lisp expressions to be passed as the
  6628. @code{#:entry-program} argument.
  6629. By default, all the @file{.asd} files present in the sources are read to
  6630. find system definitions. The @code{#:asd-files} parameter can be used
  6631. to specify the list of @file{.asd} files to read. Furthermore, if the
  6632. package defines a system for its tests in a separate file, it will be
  6633. loaded before the tests are run if it is specified by the
  6634. @code{#:test-asd-file} parameter. If it is not set, the files
  6635. @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
  6636. and @code{test.asd} will be tried if they exist.
  6637. If for some reason the package must be named in a different way than the
  6638. naming conventions suggest, or if several systems must be compiled, the
  6639. @code{#:asd-systems} parameter can be used to specify the list of system
  6640. names.
  6641. @end defvr
  6642. @defvr {Scheme Variable} cargo-build-system
  6643. @cindex Rust programming language
  6644. @cindex Cargo (Rust build system)
  6645. This variable is exported by @code{(guix build-system cargo)}. It
  6646. supports builds of packages using Cargo, the build tool of the
  6647. @uref{https://www.rust-lang.org, Rust programming language}.
  6648. It adds @code{rustc} and @code{cargo} to the set of inputs.
  6649. A different Rust package can be specified with the @code{#:rust} parameter.
  6650. Regular cargo dependencies should be added to the package definition similarly
  6651. to other packages; those needed only at build time to native-inputs, others to
  6652. inputs. If you need to add source-only crates then you should add them to via
  6653. the @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
  6654. spec can be a package or a source definition. Note that the spec must
  6655. evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
  6656. file at its root, or it will be ignored. Similarly, cargo dev-dependencies
  6657. should be added to the package definition via the
  6658. @code{#:cargo-development-inputs} parameter.
  6659. In its @code{configure} phase, this build system will make any source inputs
  6660. specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
  6661. parameters available to cargo. It will also remove an included
  6662. @code{Cargo.lock} file to be recreated by @code{cargo} during the
  6663. @code{build} phase. The @code{package} phase will run @code{cargo package}
  6664. to create a source crate for future use. The @code{install} phase installs
  6665. the binaries defined by the crate. Unless @code{install-source? #f} is
  6666. defined it will also install a source crate repository of itself and unpacked
  6667. sources, to ease in future hacking on rust packages.
  6668. @end defvr
  6669. @defvr {Scheme Variable} chicken-build-system
  6670. This variable is exported by @code{(guix build-system chicken)}. It
  6671. builds @uref{https://call-cc.org/, CHICKEN Scheme} modules, also called
  6672. ``eggs'' or ``extensions''. CHICKEN generates C source code, which then
  6673. gets compiled by a C compiler, in this case GCC.
  6674. This build system adds @code{chicken} to the package inputs, as well as
  6675. the packages of @code{gnu-build-system}.
  6676. The build system can't (yet) deduce the egg's name automatically, so just like
  6677. with @code{go-build-system} and its @code{#:import-path}, you should define
  6678. @code{#:egg-name} in the package's @code{arguments} field.
  6679. For example, if you are packaging the @code{srfi-1} egg:
  6680. @lisp
  6681. (arguments '(#:egg-name "srfi-1"))
  6682. @end lisp
  6683. Egg dependencies must be defined in @code{propagated-inputs}, not @code{inputs}
  6684. because CHICKEN doesn't embed absolute references in compiled eggs.
  6685. Test dependencies should go to @code{native-inputs}, as usual.
  6686. @end defvr
  6687. @defvr {Scheme Variable} copy-build-system
  6688. This variable is exported by @code{(guix build-system copy)}. It
  6689. supports builds of simple packages that don't require much compiling,
  6690. mostly just moving files around.
  6691. It adds much of the @code{gnu-build-system} packages to the set of
  6692. inputs. Because of this, the @code{copy-build-system} does not require
  6693. all the boilerplate code often needed for the
  6694. @code{trivial-build-system}.
  6695. To further simplify the file installation process, an
  6696. @code{#:install-plan} argument is exposed to let the packager specify
  6697. which files go where. The install plan is a list of @code{(@var{source}
  6698. @var{target} [@var{filters}])}. @var{filters} are optional.
  6699. @itemize
  6700. @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
  6701. @itemize
  6702. @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
  6703. @item Otherwise install @var{source} as @var{target}.
  6704. @end itemize
  6705. @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
  6706. the trailing slash of @var{target} is implied with the same meaning
  6707. as above.
  6708. @itemize
  6709. @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
  6710. @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
  6711. @code{#:exclude-regexp}, only select files are installed depending on
  6712. the filters. Each filters is specified by a list of strings.
  6713. @itemize
  6714. @item With @code{#:include}, install all the files which the path suffix matches
  6715. at least one of the elements in the given list.
  6716. @item With @code{#:include-regexp}, install all the files which the
  6717. subpaths match at least one of the regular expressions in the given
  6718. list.
  6719. @item The @code{#:exclude} and @code{#:exclude-regexp} filters
  6720. are the complement of their inclusion counterpart. Without @code{#:include} flags,
  6721. install all files but those matching the exclusion filters.
  6722. If both inclusions and exclusions are specified, the exclusions are done
  6723. on top of the inclusions.
  6724. @end itemize
  6725. @end itemize
  6726. In all cases, the paths relative to @var{source} are preserved within
  6727. @var{target}.
  6728. @end itemize
  6729. Examples:
  6730. @itemize
  6731. @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
  6732. @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
  6733. @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
  6734. e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
  6735. @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
  6736. @file{share/my-app/sub/file}.
  6737. @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
  6738. @file{share/my-app/file}.
  6739. @end itemize
  6740. @end defvr
  6741. @cindex Clojure (programming language)
  6742. @cindex simple Clojure build system
  6743. @defvr {Scheme Variable} clojure-build-system
  6744. This variable is exported by @code{(guix build-system clojure)}. It implements
  6745. a simple build procedure for @uref{https://clojure.org/, Clojure} packages
  6746. using plain old @code{compile} in Clojure. Cross-compilation is not supported
  6747. yet.
  6748. It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
  6749. Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
  6750. @code{#:zip} parameters, respectively.
  6751. A list of source directories, test directories and jar names can be specified
  6752. with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
  6753. parameters, respectively. Compile directory and main class can be specified
  6754. with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
  6755. Other parameters are documented below.
  6756. This build system is an extension of @code{ant-build-system}, but with the
  6757. following phases changed:
  6758. @table @code
  6759. @item build
  6760. This phase calls @code{compile} in Clojure to compile source files and runs
  6761. @command{jar} to create jars from both source files and compiled files
  6762. according to the include list and exclude list specified in
  6763. @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
  6764. has priority over the include list. These lists consist of symbols
  6765. representing Clojure libraries or the special keyword @code{#:all} representing
  6766. all Clojure libraries found under the source directories. The parameter
  6767. @code{#:omit-source?} decides if source should be included into the jars.
  6768. @item check
  6769. This phase runs tests according to the include list and exclude list specified
  6770. in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
  6771. meanings are analogous to that of @code{#:aot-include} and
  6772. @code{#:aot-exclude}, except that the special keyword @code{#:all} now
  6773. stands for all Clojure libraries found under the test directories. The
  6774. parameter @code{#:tests?} decides if tests should be run.
  6775. @item install
  6776. This phase installs all jars built previously.
  6777. @end table
  6778. Apart from the above, this build system also contains an additional phase:
  6779. @table @code
  6780. @item install-doc
  6781. This phase installs all top-level files with base name matching
  6782. @code{%doc-regex}. A different regex can be specified with the
  6783. @code{#:doc-regex} parameter. All files (recursively) inside the documentation
  6784. directories specified in @code{#:doc-dirs} are installed as well.
  6785. @end table
  6786. @end defvr
  6787. @defvr {Scheme Variable} cmake-build-system
  6788. This variable is exported by @code{(guix build-system cmake)}. It
  6789. implements the build procedure for packages using the
  6790. @url{https://www.cmake.org, CMake build tool}.
  6791. It automatically adds the @code{cmake} package to the set of inputs.
  6792. Which package is used can be specified with the @code{#:cmake}
  6793. parameter.
  6794. The @code{#:configure-flags} parameter is taken as a list of flags
  6795. passed to the @command{cmake} command. The @code{#:build-type}
  6796. parameter specifies in abstract terms the flags passed to the compiler;
  6797. it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
  6798. debugging information''), which roughly means that code is compiled with
  6799. @code{-O2 -g}, as is the case for Autoconf-based packages by default.
  6800. @end defvr
  6801. @defvr {Scheme Variable} dune-build-system
  6802. This variable is exported by @code{(guix build-system dune)}. It
  6803. supports builds of packages using @uref{https://dune.build/, Dune}, a build
  6804. tool for the OCaml programming language. It is implemented as an extension
  6805. of the @code{ocaml-build-system} which is described below. As such, the
  6806. @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
  6807. system.
  6808. It automatically adds the @code{dune} package to the set of inputs.
  6809. Which package is used can be specified with the @code{#:dune}
  6810. parameter.
  6811. There is no @code{configure} phase because dune packages typically don't
  6812. need to be configured. The @code{#:build-flags} parameter is taken as a
  6813. list of flags passed to the @code{dune} command during the build.
  6814. The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
  6815. command instead of the more recent @code{dune} command while building
  6816. a package. Its default value is @code{#f}.
  6817. The @code{#:package} parameter can be passed to specify a package name, which
  6818. is useful when a package contains multiple packages and you want to build
  6819. only one of them. This is equivalent to passing the @code{-p} argument to
  6820. @code{dune}.
  6821. @end defvr
  6822. @defvr {Scheme Variable} go-build-system
  6823. This variable is exported by @code{(guix build-system go)}. It
  6824. implements a build procedure for Go packages using the standard
  6825. @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
  6826. Go build mechanisms}.
  6827. The user is expected to provide a value for the key @code{#:import-path}
  6828. and, in some cases, @code{#:unpack-path}. The
  6829. @url{https://golang.org/doc/code.html#ImportPaths, import path}
  6830. corresponds to the file system path expected by the package's build
  6831. scripts and any referring packages, and provides a unique way to
  6832. refer to a Go package. It is typically based on a combination of the
  6833. package source code's remote URI and file system hierarchy structure. In
  6834. some cases, you will need to unpack the package's source code to a
  6835. different directory structure than the one indicated by the import path,
  6836. and @code{#:unpack-path} should be used in such cases.
  6837. Packages that provide Go libraries should install their source code into
  6838. the built output. The key @code{#:install-source?}, which defaults to
  6839. @code{#t}, controls whether or not the source code is installed. It can
  6840. be set to @code{#f} for packages that only provide executable files.
  6841. Packages can be cross-built, and if a specific architecture or operating
  6842. system is desired then the keywords @code{#:goarch} and @code{#:goos}
  6843. can be used to force the package to be built for that architecture and
  6844. operating system. The combinations known to Go can be found
  6845. @url{"https://golang.org/doc/install/source#environment", in their
  6846. documentation}.
  6847. @end defvr
  6848. @defvr {Scheme Variable} glib-or-gtk-build-system
  6849. This variable is exported by @code{(guix build-system glib-or-gtk)}. It
  6850. is intended for use with packages making use of GLib or GTK+.
  6851. This build system adds the following two phases to the ones defined by
  6852. @code{gnu-build-system}:
  6853. @table @code
  6854. @item glib-or-gtk-wrap
  6855. The phase @code{glib-or-gtk-wrap} ensures that programs in
  6856. @file{bin/} are able to find GLib ``schemas'' and
  6857. @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
  6858. modules}. This is achieved by wrapping the programs in launch scripts
  6859. that appropriately set the @env{XDG_DATA_DIRS} and @env{GTK_PATH}
  6860. environment variables.
  6861. It is possible to exclude specific package outputs from that wrapping
  6862. process by listing their names in the
  6863. @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
  6864. when an output is known not to contain any GLib or GTK+ binaries, and
  6865. where wrapping would gratuitously add a dependency of that output on
  6866. GLib and GTK+.
  6867. @item glib-or-gtk-compile-schemas
  6868. The phase @code{glib-or-gtk-compile-schemas} makes sure that all
  6869. @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
  6870. GSettings schemas} of GLib are compiled. Compilation is performed by the
  6871. @command{glib-compile-schemas} program. It is provided by the package
  6872. @code{glib:bin} which is automatically imported by the build system.
  6873. The @code{glib} package providing @command{glib-compile-schemas} can be
  6874. specified with the @code{#:glib} parameter.
  6875. @end table
  6876. Both phases are executed after the @code{install} phase.
  6877. @end defvr
  6878. @defvr {Scheme Variable} guile-build-system
  6879. This build system is for Guile packages that consist exclusively of Scheme
  6880. code and that are so lean that they don't even have a makefile, let alone a
  6881. @file{configure} script. It compiles Scheme code using @command{guild
  6882. compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
  6883. installs the @file{.scm} and @file{.go} files in the right place. It also
  6884. installs documentation.
  6885. This build system supports cross-compilation by using the
  6886. @option{--target} option of @samp{guild compile}.
  6887. Packages built with @code{guile-build-system} must provide a Guile package in
  6888. their @code{native-inputs} field.
  6889. @end defvr
  6890. @defvr {Scheme Variable} julia-build-system
  6891. This variable is exported by @code{(guix build-system julia)}. It
  6892. implements the build procedure used by @uref{https://julialang.org/,
  6893. julia} packages, which essentially is similar to running @samp{julia -e
  6894. 'using Pkg; Pkg.add(package)'} in an environment where
  6895. @env{JULIA_LOAD_PATH} contains the paths to all Julia package inputs.
  6896. Tests are run by calling @code{/test/runtests.jl}.
  6897. The Julia package name and uuid is read from the file
  6898. @file{Project.toml}. These values can be overridden by passing the
  6899. argument @code{#:julia-package-name} (which must be correctly
  6900. capitalized) or @code{#:julia-package-uuid}.
  6901. Julia packages usually manage their binary dependencies via
  6902. @code{JLLWrappers.jl}, a Julia package that creates a module (named
  6903. after the wrapped library followed by @code{_jll.jl}.
  6904. To add the binary path @code{_jll.jl} packages, you need to patch the
  6905. files under @file{src/wrappers/}, replacing the call to the macro
  6906. @code{JLLWrappers.@@generate_wrapper_header}, adding as a second
  6907. argument containing the store path the binary.
  6908. As an example, in the MbedTLS Julia package, we add a build phase
  6909. (@pxref{Build Phases}) to insert the absolute file name of the wrapped
  6910. MbedTLS package:
  6911. @lisp
  6912. (add-after 'unpack 'override-binary-path
  6913. (lambda* (#:key inputs #:allow-other-keys)
  6914. (for-each (lambda (wrapper)
  6915. (substitute* wrapper
  6916. (("generate_wrapper_header.*")
  6917. (string-append
  6918. "generate_wrapper_header(\"MbedTLS\", \""
  6919. (assoc-ref inputs "mbedtls-apache") "\")\n"))))
  6920. ;; There's a Julia file for each platform, override them all.
  6921. (find-files "src/wrappers/" "\\.jl$"))))
  6922. @end lisp
  6923. Some older packages that aren't using @file{Project.toml} yet, will
  6924. require this file to be created, too. It is internally done if the
  6925. arguments @code{#:julia-package-name} and @code{#:julia-package-uuid}
  6926. are provided.
  6927. @end defvr
  6928. @defvr {Scheme Variable} maven-build-system
  6929. This variable is exported by @code{(guix build-system maven)}. It implements
  6930. a build procedure for @uref{https://maven.apache.org, Maven} packages. Maven
  6931. is a dependency and lifecycle management tool for Java. A user of Maven
  6932. specifies dependencies and plugins in a @file{pom.xml} file that Maven reads.
  6933. When Maven does not have one of the dependencies or plugins in its repository,
  6934. it will download them and use them to build the package.
  6935. The maven build system ensures that maven will not try to download any
  6936. dependency by running in offline mode. Maven will fail if a dependency is
  6937. missing. Before running Maven, the @file{pom.xml} (and subprojects) are
  6938. modified to specify the version of dependencies and plugins that match the
  6939. versions available in the guix build environment. Dependencies and plugins
  6940. must be installed in the fake maven repository at @file{lib/m2}, and are
  6941. symlinked into a proper repository before maven is run. Maven is instructed
  6942. to use that repository for the build and installs built artifacts there.
  6943. Changed files are copied to the @file{lib/m2} directory of the package output.
  6944. You can specify a @file{pom.xml} file with the @code{#:pom-file} argument,
  6945. or let the build system use the default @file{pom.xml} file in the sources.
  6946. In case you need to specify a dependency's version manually, you can use the
  6947. @code{#:local-packages} argument. It takes an association list where the key
  6948. is the groupId of the package and its value is an association list where the
  6949. key is the artifactId of the package and its value is the version you want to
  6950. override in the @file{pom.xml}.
  6951. Some packages use dependencies or plugins that are not useful at runtime nor
  6952. at build time in Guix. You can alter the @file{pom.xml} file to remove them
  6953. using the @code{#:exclude} argument. Its value is an association list where
  6954. the key is the groupId of the plugin or dependency you want to remove, and
  6955. the value is a list of artifactId you want to remove.
  6956. You can override the default @code{jdk} and @code{maven} packages with the
  6957. corresponding argument, @code{#:jdk} and @code{#:maven}.
  6958. The @code{#:maven-plugins} argument is a list of maven plugins used during
  6959. the build, with the same format as the @code{inputs} fields of the package
  6960. declaration. Its default value is @code{(default-maven-plugins)} which is
  6961. also exported.
  6962. @end defvr
  6963. @defvr {Scheme Variable} minetest-mod-build-system
  6964. This variable is exported by @code{(guix build-system minetest)}. It
  6965. implements a build procedure for @uref{https://www.minetest.net, Minetest}
  6966. mods, which consists of copying Lua code, images and other resources to
  6967. the location Minetest searches for mods. The build system also minimises
  6968. PNG images and verifies that Minetest can load the mod without errors.
  6969. @end defvr
  6970. @defvr {Scheme Variable} minify-build-system
  6971. This variable is exported by @code{(guix build-system minify)}. It
  6972. implements a minification procedure for simple JavaScript packages.
  6973. It adds @code{uglify-js} to the set of inputs and uses it to compress
  6974. all JavaScript files in the @file{src} directory. A different minifier
  6975. package can be specified with the @code{#:uglify-js} parameter, but it
  6976. is expected that the package writes the minified code to the standard
  6977. output.
  6978. When the input JavaScript files are not all located in the @file{src}
  6979. directory, the parameter @code{#:javascript-files} can be used to
  6980. specify a list of file names to feed to the minifier.
  6981. @end defvr
  6982. @defvr {Scheme Variable} ocaml-build-system
  6983. This variable is exported by @code{(guix build-system ocaml)}. It implements
  6984. a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
  6985. of choosing the correct set of commands to run for each package. OCaml
  6986. packages can expect many different commands to be run. This build system will
  6987. try some of them.
  6988. When the package has a @file{setup.ml} file present at the top-level, it will
  6989. run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
  6990. @code{ocaml setup.ml -install}. The build system will assume that this file
  6991. was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
  6992. care of setting the prefix and enabling tests if they are not disabled. You
  6993. can pass configure and build flags with the @code{#:configure-flags} and
  6994. @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
  6995. set of flags used to enable tests. The @code{#:use-make?} key can be used to
  6996. bypass this system in the build and install phases.
  6997. When the package has a @file{configure} file, it is assumed that it is a
  6998. hand-made configure script that requires a different argument format than
  6999. in the @code{gnu-build-system}. You can add more flags with the
  7000. @code{#:configure-flags} key.
  7001. When the package has a @file{Makefile} file (or @code{#:use-make?} is
  7002. @code{#t}), it will be used and more flags can be passed to the build and
  7003. install phases with the @code{#:make-flags} key.
  7004. Finally, some packages do not have these files and use a somewhat standard
  7005. location for its build system. In that case, the build system will run
  7006. @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
  7007. providing the path to the required findlib module. Additional flags can
  7008. be passed via the @code{#:build-flags} key. Install is taken care of by
  7009. @command{opam-installer}. In this case, the @code{opam} package must
  7010. be added to the @code{native-inputs} field of the package definition.
  7011. Note that most OCaml packages assume they will be installed in the same
  7012. directory as OCaml, which is not what we want in guix. In particular, they
  7013. will install @file{.so} files in their module's directory, which is usually
  7014. fine because it is in the OCaml compiler directory. In guix though, these
  7015. libraries cannot be found and we use @env{CAML_LD_LIBRARY_PATH}. This
  7016. variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
  7017. @file{.so} libraries should be installed.
  7018. @end defvr
  7019. @defvr {Scheme Variable} python-build-system
  7020. This variable is exported by @code{(guix build-system python)}. It
  7021. implements the more or less standard build procedure used by Python
  7022. packages, which consists in running @code{python setup.py build} and
  7023. then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
  7024. For packages that install stand-alone Python programs under @code{bin/},
  7025. it takes care of wrapping these programs so that their
  7026. @env{GUIX_PYTHONPATH} environment variable points to all the Python
  7027. libraries they depend on.
  7028. Which Python package is used to perform the build can be specified with
  7029. the @code{#:python} parameter. This is a useful way to force a package
  7030. to be built for a specific version of the Python interpreter, which
  7031. might be necessary if the package is only compatible with a single
  7032. interpreter version.
  7033. By default guix calls @code{setup.py} under control of
  7034. @code{setuptools}, much like @command{pip} does. Some packages are not
  7035. compatible with setuptools (and pip), thus you can disable this by
  7036. setting the @code{#:use-setuptools?} parameter to @code{#f}.
  7037. If a @code{"python"} output is available, the package is installed into it
  7038. instead of the default @code{"out"} output. This is useful for packages that
  7039. include a Python package as only a part of the software, and thus want to
  7040. combine the phases of @code{python-build-system} with another build system.
  7041. Python bindings are a common usecase.
  7042. @end defvr
  7043. @defvr {Scheme Variable} perl-build-system
  7044. This variable is exported by @code{(guix build-system perl)}. It
  7045. implements the standard build procedure for Perl packages, which either
  7046. consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
  7047. followed by @code{Build} and @code{Build install}; or in running
  7048. @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
  7049. @code{make} and @code{make install}, depending on which of
  7050. @code{Build.PL} or @code{Makefile.PL} is present in the package
  7051. distribution. Preference is given to the former if both @code{Build.PL}
  7052. and @code{Makefile.PL} exist in the package distribution. This
  7053. preference can be reversed by specifying @code{#t} for the
  7054. @code{#:make-maker?} parameter.
  7055. The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
  7056. passes flags specified by the @code{#:make-maker-flags} or
  7057. @code{#:module-build-flags} parameter, respectively.
  7058. Which Perl package is used can be specified with @code{#:perl}.
  7059. @end defvr
  7060. @defvr {Scheme Variable} renpy-build-system
  7061. This variable is exported by @code{(guix build-system renpy)}. It implements
  7062. the more or less standard build procedure used by Ren'py games, which consists
  7063. of loading @code{#:game} once, thereby creating bytecode for it.
  7064. It further creates a wrapper script in @code{bin/} and a desktop entry in
  7065. @code{share/applications}, both of which can be used to launch the game.
  7066. Which Ren'py package is used can be specified with @code{#:renpy}.
  7067. Games can also be installed in outputs other than ``out'' by using
  7068. @code{#:output}.
  7069. @end defvr
  7070. @defvr {Scheme Variable} qt-build-system
  7071. This variable is exported by @code{(guix build-system qt)}. It
  7072. is intended for use with applications using Qt or KDE.
  7073. This build system adds the following two phases to the ones defined by
  7074. @code{cmake-build-system}:
  7075. @table @code
  7076. @item check-setup
  7077. The phase @code{check-setup} prepares the environment for running
  7078. the checks as commonly used by Qt test programs.
  7079. For now this only sets some environment variables:
  7080. @code{QT_QPA_PLATFORM=offscreen},
  7081. @code{DBUS_FATAL_WARNINGS=0} and
  7082. @code{CTEST_OUTPUT_ON_FAILURE=1}.
  7083. This phase is added before the @code{check} phase.
  7084. It's a separate phase to ease adjusting if necessary.
  7085. @item qt-wrap
  7086. The phase @code{qt-wrap}
  7087. searches for Qt5 plugin paths, QML paths and some XDG in the inputs
  7088. and output. In case some path is found, all programs in the output's
  7089. @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
  7090. are wrapped in scripts defining the necessary environment variables.
  7091. It is possible to exclude specific package outputs from that wrapping process
  7092. by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
  7093. This is useful when an output is known not to contain any Qt binaries, and
  7094. where wrapping would gratuitously add a dependency of that output on Qt, KDE,
  7095. or such.
  7096. This phase is added after the @code{install} phase.
  7097. @end table
  7098. @end defvr
  7099. @defvr {Scheme Variable} r-build-system
  7100. This variable is exported by @code{(guix build-system r)}. It
  7101. implements the build procedure used by @uref{https://r-project.org, R}
  7102. packages, which essentially is little more than running @samp{R CMD
  7103. INSTALL --library=/gnu/store/@dots{}} in an environment where
  7104. @env{R_LIBS_SITE} contains the paths to all R package inputs. Tests are
  7105. run after installation using the R function
  7106. @code{tools::testInstalledPackage}.
  7107. @end defvr
  7108. @defvr {Scheme Variable} rakudo-build-system
  7109. This variable is exported by @code{(guix build-system rakudo)}. It
  7110. implements the build procedure used by @uref{https://rakudo.org/,
  7111. Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
  7112. package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
  7113. installs the binaries, library files and the resources, as well as wrap
  7114. the files under the @code{bin/} directory. Tests can be skipped by
  7115. passing @code{#f} to the @code{tests?} parameter.
  7116. Which rakudo package is used can be specified with @code{rakudo}.
  7117. Which perl6-tap-harness package used for the tests can be specified with
  7118. @code{#:prove6} or removed by passing @code{#f} to the
  7119. @code{with-prove6?} parameter.
  7120. Which perl6-zef package used for tests and installing can be specified
  7121. with @code{#:zef} or removed by passing @code{#f} to the
  7122. @code{with-zef?} parameter.
  7123. @end defvr
  7124. @defvr {Scheme Variable} texlive-build-system
  7125. This variable is exported by @code{(guix build-system texlive)}. It is
  7126. used to build TeX packages in batch mode with a specified engine. The
  7127. build system sets the @env{TEXINPUTS} variable to find all TeX source
  7128. files in the inputs.
  7129. By default it runs @code{luatex} on all files ending on @code{ins}. A
  7130. different engine and format can be specified with the
  7131. @code{#:tex-format} argument. Different build targets can be specified
  7132. with the @code{#:build-targets} argument, which expects a list of file
  7133. names. The build system adds only @code{texlive-bin} and
  7134. @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
  7135. inputs. Both can be overridden with the arguments @code{#:texlive-bin}
  7136. and @code{#:texlive-latex-base}, respectively.
  7137. The @code{#:tex-directory} parameter tells the build system where to
  7138. install the built files under the texmf tree.
  7139. @end defvr
  7140. @defvr {Scheme Variable} ruby-build-system
  7141. This variable is exported by @code{(guix build-system ruby)}. It
  7142. implements the RubyGems build procedure used by Ruby packages, which
  7143. involves running @code{gem build} followed by @code{gem install}.
  7144. The @code{source} field of a package that uses this build system
  7145. typically references a gem archive, since this is the format that Ruby
  7146. developers use when releasing their software. The build system unpacks
  7147. the gem archive, potentially patches the source, runs the test suite,
  7148. repackages the gem, and installs it. Additionally, directories and
  7149. tarballs may be referenced to allow building unreleased gems from Git or
  7150. a traditional source release tarball.
  7151. Which Ruby package is used can be specified with the @code{#:ruby}
  7152. parameter. A list of additional flags to be passed to the @command{gem}
  7153. command can be specified with the @code{#:gem-flags} parameter.
  7154. @end defvr
  7155. @defvr {Scheme Variable} waf-build-system
  7156. This variable is exported by @code{(guix build-system waf)}. It
  7157. implements a build procedure around the @code{waf} script. The common
  7158. phases---@code{configure}, @code{build}, and @code{install}---are
  7159. implemented by passing their names as arguments to the @code{waf}
  7160. script.
  7161. The @code{waf} script is executed by the Python interpreter. Which
  7162. Python package is used to run the script can be specified with the
  7163. @code{#:python} parameter.
  7164. @end defvr
  7165. @defvr {Scheme Variable} scons-build-system
  7166. This variable is exported by @code{(guix build-system scons)}. It
  7167. implements the build procedure used by the SCons software construction
  7168. tool. This build system runs @code{scons} to build the package,
  7169. @code{scons test} to run tests, and then @code{scons install} to install
  7170. the package.
  7171. Additional flags to be passed to @code{scons} can be specified with the
  7172. @code{#:scons-flags} parameter. The default build and install targets
  7173. can be overridden with @code{#:build-targets} and
  7174. @code{#:install-targets} respectively. The version of Python used to
  7175. run SCons can be specified by selecting the appropriate SCons package
  7176. with the @code{#:scons} parameter.
  7177. @end defvr
  7178. @defvr {Scheme Variable} haskell-build-system
  7179. This variable is exported by @code{(guix build-system haskell)}. It
  7180. implements the Cabal build procedure used by Haskell packages, which
  7181. involves running @code{runhaskell Setup.hs configure
  7182. --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
  7183. Instead of installing the package by running @code{runhaskell Setup.hs
  7184. install}, to avoid trying to register libraries in the read-only
  7185. compiler store directory, the build system uses @code{runhaskell
  7186. Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
  7187. addition, the build system generates the package documentation by
  7188. running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
  7189. is passed. Optional Haddock parameters can be passed with the help of
  7190. the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
  7191. not found, the build system looks for @code{Setup.lhs} instead.
  7192. Which Haskell compiler is used can be specified with the @code{#:haskell}
  7193. parameter which defaults to @code{ghc}.
  7194. @end defvr
  7195. @defvr {Scheme Variable} dub-build-system
  7196. This variable is exported by @code{(guix build-system dub)}. It
  7197. implements the Dub build procedure used by D packages, which
  7198. involves running @code{dub build} and @code{dub run}.
  7199. Installation is done by copying the files manually.
  7200. Which D compiler is used can be specified with the @code{#:ldc}
  7201. parameter which defaults to @code{ldc}.
  7202. @end defvr
  7203. @anchor{emacs-build-system}
  7204. @defvr {Scheme Variable} emacs-build-system
  7205. This variable is exported by @code{(guix build-system emacs)}. It
  7206. implements an installation procedure similar to the packaging system
  7207. of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
  7208. It first creates the @code{@code{package}-autoloads.el} file, then it
  7209. byte compiles all Emacs Lisp files. Differently from the Emacs
  7210. packaging system, the Info documentation files are moved to the standard
  7211. documentation directory and the @file{dir} file is deleted. The Elisp
  7212. package files are installed directly under @file{share/emacs/site-lisp}.
  7213. @end defvr
  7214. @defvr {Scheme Variable} font-build-system
  7215. This variable is exported by @code{(guix build-system font)}. It
  7216. implements an installation procedure for font packages where upstream
  7217. provides pre-compiled TrueType, OpenType, etc.@: font files that merely
  7218. need to be copied into place. It copies font files to standard
  7219. locations in the output directory.
  7220. @end defvr
  7221. @defvr {Scheme Variable} meson-build-system
  7222. This variable is exported by @code{(guix build-system meson)}. It
  7223. implements the build procedure for packages that use
  7224. @url{https://mesonbuild.com, Meson} as their build system.
  7225. It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
  7226. of inputs, and they can be changed with the parameters @code{#:meson}
  7227. and @code{#:ninja} if needed.
  7228. This build system is an extension of @code{gnu-build-system}, but with the
  7229. following phases changed to some specific for Meson:
  7230. @table @code
  7231. @item configure
  7232. The phase runs @code{meson} with the flags specified in
  7233. @code{#:configure-flags}. The flag @option{--buildtype} is always set to
  7234. @code{debugoptimized} unless something else is specified in
  7235. @code{#:build-type}.
  7236. @item build
  7237. The phase runs @code{ninja} to build the package in parallel by default, but
  7238. this can be changed with @code{#:parallel-build?}.
  7239. @item check
  7240. The phase runs @samp{meson test} with a base set of options that cannot
  7241. be overridden. This base set of options can be extended via the
  7242. @code{#:test-options} argument, for example to select or skip a specific
  7243. test suite.
  7244. @item install
  7245. The phase runs @code{ninja install} and can not be changed.
  7246. @end table
  7247. Apart from that, the build system also adds the following phases:
  7248. @table @code
  7249. @item fix-runpath
  7250. This phase ensures that all binaries can find the libraries they need.
  7251. It searches for required libraries in subdirectories of the package
  7252. being built, and adds those to @code{RUNPATH} where needed. It also
  7253. removes references to libraries left over from the build phase by
  7254. @code{meson}, such as test dependencies, that aren't actually required
  7255. for the program to run.
  7256. @item glib-or-gtk-wrap
  7257. This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
  7258. is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
  7259. @item glib-or-gtk-compile-schemas
  7260. This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
  7261. is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
  7262. @end table
  7263. @end defvr
  7264. @defvr {Scheme Variable} linux-module-build-system
  7265. @code{linux-module-build-system} allows building Linux kernel modules.
  7266. @cindex build phases
  7267. This build system is an extension of @code{gnu-build-system}, but with the
  7268. following phases changed:
  7269. @table @code
  7270. @item configure
  7271. This phase configures the environment so that the Linux kernel's Makefile
  7272. can be used to build the external kernel module.
  7273. @item build
  7274. This phase uses the Linux kernel's Makefile in order to build the external
  7275. kernel module.
  7276. @item install
  7277. This phase uses the Linux kernel's Makefile in order to install the external
  7278. kernel module.
  7279. @end table
  7280. It is possible and useful to specify the Linux kernel to use for building
  7281. the module (in the @code{arguments} form of a package using the
  7282. @code{linux-module-build-system}, use the key @code{#:linux} to specify it).
  7283. @end defvr
  7284. @defvr {Scheme Variable} node-build-system
  7285. This variable is exported by @code{(guix build-system node)}. It
  7286. implements the build procedure used by @uref{https://nodejs.org,
  7287. Node.js}, which implements an approximation of the @code{npm install}
  7288. command, followed by an @code{npm test} command.
  7289. Which Node.js package is used to interpret the @code{npm} commands can
  7290. be specified with the @code{#:node} parameter which defaults to
  7291. @code{node}.
  7292. @end defvr
  7293. Lastly, for packages that do not need anything as sophisticated, a
  7294. ``trivial'' build system is provided. It is trivial in the sense that
  7295. it provides basically no support: it does not pull any implicit inputs,
  7296. and does not have a notion of build phases.
  7297. @defvr {Scheme Variable} trivial-build-system
  7298. This variable is exported by @code{(guix build-system trivial)}.
  7299. This build system requires a @code{#:builder} argument. This argument
  7300. must be a Scheme expression that builds the package output(s)---as
  7301. with @code{build-expression->derivation} (@pxref{Derivations,
  7302. @code{build-expression->derivation}}).
  7303. @end defvr
  7304. @node Build Phases
  7305. @section Build Phases
  7306. @cindex build phases, for packages
  7307. Almost all package build systems implement a notion @dfn{build phases}:
  7308. a sequence of actions that the build system executes, when you build the
  7309. package, leading to the installed byproducts in the store. A notable
  7310. exception is the ``bare-bones'' @code{trivial-build-system}
  7311. (@pxref{Build Systems}).
  7312. As discussed in the previous section, those build systems provide a
  7313. standard list of phases. For @code{gnu-build-system}, the main build
  7314. phases are the following:
  7315. @table @code
  7316. @item set-paths
  7317. Define search path environment variables for all the input packages,
  7318. including @env{PATH} (@pxref{Search Paths}).
  7319. @item unpack
  7320. Unpack the source tarball, and change the current directory to the
  7321. extracted source tree. If the source is actually a directory, copy it
  7322. to the build tree, and enter that directory.
  7323. @item patch-source-shebangs
  7324. Patch shebangs encountered in source files so they refer to the right
  7325. store file names. For instance, this changes @code{#!/bin/sh} to
  7326. @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
  7327. @item configure
  7328. Run the @file{configure} script with a number of default options, such
  7329. as @option{--prefix=/gnu/store/@dots{}}, as well as the options specified
  7330. by the @code{#:configure-flags} argument.
  7331. @item build
  7332. Run @code{make} with the list of flags specified with
  7333. @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
  7334. (the default), build with @code{make -j}.
  7335. @item check
  7336. Run @code{make check}, or some other target specified with
  7337. @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
  7338. @code{#:parallel-tests?} argument is true (the default), run @code{make
  7339. check -j}.
  7340. @item install
  7341. Run @code{make install} with the flags listed in @code{#:make-flags}.
  7342. @item patch-shebangs
  7343. Patch shebangs on the installed executable files.
  7344. @item strip
  7345. Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
  7346. is false), copying them to the @code{debug} output when available
  7347. (@pxref{Installing Debugging Files}).
  7348. @end table
  7349. Other build systems have similar phases, with some variations. For
  7350. example, @code{cmake-build-system} has same-named phases but its
  7351. @code{configure} phases runs @code{cmake} instead of @code{./configure}.
  7352. Others, such as @code{python-build-system}, have a wholly different list
  7353. of standard phases. All this code runs on the @dfn{build side}: it is
  7354. evaluated when you actually build the package, in a dedicated build
  7355. process spawned by the build daemon (@pxref{Invoking guix-daemon}).
  7356. Build phases are represented as association lists or ``alists''
  7357. (@pxref{Association Lists,,, guile, GNU Guile Reference Manual}) where
  7358. each key is a symbol for the name of the phase and the associated value
  7359. is a procedure that accepts an arbitrary number of arguments. By
  7360. convention, those procedures receive information about the build in the
  7361. form of @dfn{keyword parameters}, which they can use or ignore.
  7362. @vindex %standard-phases
  7363. For example, here is how @code{(guix build gnu-build-system)} defines
  7364. @code{%standard-phases}, the variable holding its alist of build
  7365. phases@footnote{We present a simplified view of those build phases, but
  7366. do take a look at @code{(guix build gnu-build-system)} to see all the
  7367. details!}:
  7368. @lisp
  7369. ;; The build phases of 'gnu-build-system'.
  7370. (define* (unpack #:key source #:allow-other-keys)
  7371. ;; Extract the source tarball.
  7372. (invoke "tar" "xvf" source))
  7373. (define* (configure #:key outputs #:allow-other-keys)
  7374. ;; Run the 'configure' script. Install to output "out".
  7375. (let ((out (assoc-ref outputs "out")))
  7376. (invoke "./configure"
  7377. (string-append "--prefix=" out))))
  7378. (define* (build #:allow-other-keys)
  7379. ;; Compile.
  7380. (invoke "make"))
  7381. (define* (check #:key (test-target "check") (tests? #true)
  7382. #:allow-other-keys)
  7383. ;; Run the test suite.
  7384. (if tests?
  7385. (invoke "make" test-target)
  7386. (display "test suite not run\n")))
  7387. (define* (install #:allow-other-keys)
  7388. ;; Install files to the prefix 'configure' specified.
  7389. (invoke "make" "install"))
  7390. (define %standard-phases
  7391. ;; The list of standard phases (quite a few are omitted
  7392. ;; for brevity). Each element is a symbol/procedure pair.
  7393. (list (cons 'unpack unpack)
  7394. (cons 'configure configure)
  7395. (cons 'build build)
  7396. (cons 'check check)
  7397. (cons 'install install)))
  7398. @end lisp
  7399. This shows how @code{%standard-phases} is defined as a list of
  7400. symbol/procedure pairs (@pxref{Pairs,,, guile, GNU Guile Reference
  7401. Manual}). The first pair associates the @code{unpack} procedure with
  7402. the @code{unpack} symbol---a name; the second pair defines the
  7403. @code{configure} phase similarly, and so on. When building a package
  7404. that uses @code{gnu-build-system} with its default list of phases, those
  7405. phases are executed sequentially. You can see the name of each phase
  7406. started and completed in the build log of packages that you build.
  7407. Let's now look at the procedures themselves. Each one is defined with
  7408. @code{define*}: @code{#:key} lists keyword parameters the procedure
  7409. accepts, possibly with a default value, and @code{#:allow-other-keys}
  7410. specifies that other keyword parameters are ignored (@pxref{Optional
  7411. Arguments,,, guile, GNU Guile Reference Manual}).
  7412. The @code{unpack} procedure honors the @code{source} parameter, which
  7413. the build system uses to pass the file name of the source tarball (or
  7414. version control checkout), and it ignores other parameters. The
  7415. @code{configure} phase only cares about the @code{outputs} parameter, an
  7416. alist mapping package output names to their store file name
  7417. (@pxref{Packages with Multiple Outputs}). It extracts the file name of
  7418. for @code{out}, the default output, and passes it to
  7419. @command{./configure} as the installation prefix, meaning that
  7420. @command{make install} will eventually copy all the files in that
  7421. directory (@pxref{Configuration, configuration and makefile
  7422. conventions,, standards, GNU Coding Standards}). @code{build} and
  7423. @code{install} ignore all their arguments. @code{check} honors the
  7424. @code{test-target} argument, which specifies the name of the Makefile
  7425. target to run tests; it prints a message and skips tests when
  7426. @code{tests?} is false.
  7427. @cindex build phases, customizing
  7428. The list of phases used for a particular package can be changed with the
  7429. @code{#:phases} parameter of the build system. Changing the set of
  7430. build phases boils down to building a new alist of phases based on the
  7431. @code{%standard-phases} alist described above. This can be done with
  7432. standard alist procedures such as @code{alist-delete} (@pxref{SRFI-1
  7433. Association Lists,,, guile, GNU Guile Reference Manual}); however, it is
  7434. more convenient to do so with @code{modify-phases} (@pxref{Build
  7435. Utilities, @code{modify-phases}}).
  7436. Here is an example of a package definition that removes the
  7437. @code{configure} phase of @code{%standard-phases} and inserts a new
  7438. phase before the @code{build} phase, called
  7439. @code{set-prefix-in-makefile}:
  7440. @lisp
  7441. (define-public example
  7442. (package
  7443. (name "example")
  7444. ;; other fields omitted
  7445. (build-system gnu-build-system)
  7446. (arguments
  7447. '(#:phases (modify-phases %standard-phases
  7448. (delete 'configure)
  7449. (add-before 'build 'set-prefix-in-makefile
  7450. (lambda* (#:key outputs #:allow-other-keys)
  7451. ;; Modify the makefile so that its
  7452. ;; 'PREFIX' variable points to "out".
  7453. (let ((out (assoc-ref outputs "out")))
  7454. (substitute* "Makefile"
  7455. (("PREFIX =.*")
  7456. (string-append "PREFIX = "
  7457. out "\n")))
  7458. #true))))))))
  7459. @end lisp
  7460. The new phase that is inserted is written as an anonymous procedure,
  7461. introduced with @code{lambda*}; it honors the @code{outputs} parameter
  7462. we have seen before. @xref{Build Utilities}, for more about the helpers
  7463. used by this phase, and for more examples of @code{modify-phases}.
  7464. @cindex code staging
  7465. @cindex staging, of code
  7466. Keep in mind that build phases are code evaluated at the time the
  7467. package is actually built. This explains why the whole
  7468. @code{modify-phases} expression above is quoted (it comes after the
  7469. @code{'} or apostrophe): it is @dfn{staged} for later execution.
  7470. @xref{G-Expressions}, for an explanation of code staging and the
  7471. @dfn{code strata} involved.
  7472. @node Build Utilities
  7473. @section Build Utilities
  7474. As soon as you start writing non-trivial package definitions
  7475. (@pxref{Defining Packages}) or other build actions
  7476. (@pxref{G-Expressions}), you will likely start looking for helpers for
  7477. ``shell-like'' actions---creating directories, copying and deleting
  7478. files recursively, manipulating build phases, and so on. The
  7479. @code{(guix build utils)} module provides such utility procedures.
  7480. Most build systems load @code{(guix build utils)} (@pxref{Build
  7481. Systems}). Thus, when writing custom build phases for your package
  7482. definitions, you can usually assume those procedures are in scope.
  7483. When writing G-expressions, you can import @code{(guix build utils)} on
  7484. the ``build side'' using @code{with-imported-modules} and then put it in
  7485. scope with the @code{use-modules} form (@pxref{Using Guile Modules,,,
  7486. guile, GNU Guile Reference Manual}):
  7487. @lisp
  7488. (with-imported-modules '((guix build utils)) ;import it
  7489. (computed-file "empty-tree"
  7490. #~(begin
  7491. ;; Put it in scope.
  7492. (use-modules (guix build utils))
  7493. ;; Happily use its 'mkdir-p' procedure.
  7494. (mkdir-p (string-append #$output "/a/b/c")))))
  7495. @end lisp
  7496. The remainder of this section is the reference for most of the utility
  7497. procedures provided by @code{(guix build utils)}.
  7498. @c TODO Document what's missing.
  7499. @subsection Dealing with Store File Names
  7500. This section documents procedures that deal with store file names.
  7501. @deffn {Scheme Procedure} %store-directory
  7502. Return the directory name of the store.
  7503. @end deffn
  7504. @deffn {Scheme Procedure} store-file-name? @var{file}
  7505. Return true if @var{file} is in the store.
  7506. @end deffn
  7507. @deffn {Scheme Procedure} strip-store-file-name @var{file}
  7508. Strip the @file{/gnu/store} and hash from @var{file}, a store file name.
  7509. The result is typically a @code{"@var{package}-@var{version}"} string.
  7510. @end deffn
  7511. @deffn {Scheme Procedure} package-name->name+version @var{name}
  7512. Given @var{name}, a package name like @code{"foo-0.9.1b"}, return two
  7513. values: @code{"foo"} and @code{"0.9.1b"}. When the version part is
  7514. unavailable, @var{name} and @code{#f} are returned. The first hyphen
  7515. followed by a digit is considered to introduce the version part.
  7516. @end deffn
  7517. @subsection File Types
  7518. The procedures below deal with files and file types.
  7519. @deffn {Scheme Procedure} directory-exists? @var{dir}
  7520. Return @code{#t} if @var{dir} exists and is a directory.
  7521. @end deffn
  7522. @deffn {Scheme Procedure} executable-file? @var{file}
  7523. Return @code{#t} if @var{file} exists and is executable.
  7524. @end deffn
  7525. @deffn {Scheme Procedure} symbolic-link? @var{file}
  7526. Return @code{#t} if @var{file} is a symbolic link (aka. a ``symlink'').
  7527. @end deffn
  7528. @deffn {Scheme Procedure} elf-file? @var{file}
  7529. @deffnx {Scheme Procedure} ar-file? @var{file}
  7530. @deffnx {Scheme Procedure} gzip-file? @var{file}
  7531. Return @code{#t} if @var{file} is, respectively, an ELF file, an
  7532. @code{ar} archive (such as a @file{.a} static library), or a gzip file.
  7533. @end deffn
  7534. @deffn {Scheme Procedure} reset-gzip-timestamp @var{file} [#:keep-mtime? #t]
  7535. If @var{file} is a gzip file, reset its embedded timestamp (as with
  7536. @command{gzip --no-name}) and return true. Otherwise return @code{#f}.
  7537. When @var{keep-mtime?} is true, preserve @var{file}'s modification time.
  7538. @end deffn
  7539. @subsection File Manipulation
  7540. The following procedures and macros help create, modify, and delete
  7541. files. They provide functionality comparable to common shell utilities
  7542. such as @command{mkdir -p}, @command{cp -r}, @command{rm -r}, and
  7543. @command{sed}. They complement Guile's extensive, but low-level, file
  7544. system interface (@pxref{POSIX,,, guile, GNU Guile Reference Manual}).
  7545. @deffn {Scheme Syntax} with-directory-excursion @var{directory} @var{body}@dots{}
  7546. Run @var{body} with @var{directory} as the process's current directory.
  7547. Essentially, this macro changes the current directory to @var{directory}
  7548. before evaluating @var{body}, using @code{chdir} (@pxref{Processes,,,
  7549. guile, GNU Guile Reference Manual}). It changes back to the initial
  7550. directory when the dynamic extent of @var{body} is left, be it @i{via}
  7551. normal procedure return or @i{via} a non-local exit such as an
  7552. exception.
  7553. @end deffn
  7554. @deffn {Scheme Procedure} mkdir-p @var{dir}
  7555. Create directory @var{dir} and all its ancestors.
  7556. @end deffn
  7557. @deffn {Scheme Procedure} install-file @var{file} @var{directory}
  7558. Create @var{directory} if it does not exist and copy @var{file} in there
  7559. under the same name.
  7560. @end deffn
  7561. @deffn {Scheme Procedure} make-file-writable @var{file}
  7562. Make @var{file} writable for its owner.
  7563. @end deffn
  7564. @deffn {Scheme Procedure} copy-recursively @var{source} @var{destination} @
  7565. [#:log (current-output-port)] [#:follow-symlinks? #f] @
  7566. [#:copy-file copy-file] [#:keep-mtime? #f] [#:keep-permissions? #t]
  7567. Copy @var{source} directory to @var{destination}. Follow symlinks if
  7568. @var{follow-symlinks?} is true; otherwise, just preserve them. Call
  7569. @var{copy-file} to copy regular files. When @var{keep-mtime?} is true,
  7570. keep the modification time of the files in @var{source} on those of
  7571. @var{destination}. When @var{keep-permissions?} is true, preserve file
  7572. permissions. Write verbose output to the @var{log} port.
  7573. @end deffn
  7574. @deffn {Scheme Procedure} delete-file-recursively @var{dir} @
  7575. [#:follow-mounts? #f]
  7576. Delete @var{dir} recursively, like @command{rm -rf}, without following
  7577. symlinks. Don't follow mount points either, unless @var{follow-mounts?}
  7578. is true. Report but ignore errors.
  7579. @end deffn
  7580. @deffn {Scheme Syntax} substitute* @var{file} @
  7581. ((@var{regexp} @var{match-var}@dots{}) @var{body}@dots{}) @dots{}
  7582. Substitute @var{regexp} in @var{file} by the string returned by
  7583. @var{body}. @var{body} is evaluated with each @var{match-var} bound to
  7584. the corresponding positional regexp sub-expression. For example:
  7585. @lisp
  7586. (substitute* file
  7587. (("hello")
  7588. "good morning\n")
  7589. (("foo([a-z]+)bar(.*)$" all letters end)
  7590. (string-append "baz" letters end)))
  7591. @end lisp
  7592. Here, anytime a line of @var{file} contains @code{hello}, it is replaced
  7593. by @code{good morning}. Anytime a line of @var{file} matches the second
  7594. regexp, @code{all} is bound to the complete match, @code{letters} is bound
  7595. to the first sub-expression, and @code{end} is bound to the last one.
  7596. When one of the @var{match-var} is @code{_}, no variable is bound to the
  7597. corresponding match substring.
  7598. Alternatively, @var{file} may be a list of file names, in which case
  7599. they are all subject to the substitutions.
  7600. Be careful about using @code{$} to match the end of a line; by itself it
  7601. won't match the terminating newline of a line.
  7602. @end deffn
  7603. @subsection File Search
  7604. @cindex file, searching
  7605. This section documents procedures to search and filter files.
  7606. @deffn {Scheme Procedure} file-name-predicate @var{regexp}
  7607. Return a predicate that returns true when passed a file name whose base
  7608. name matches @var{regexp}.
  7609. @end deffn
  7610. @deffn {Scheme Procedure} find-files @var{dir} [@var{pred}] @
  7611. [#:stat lstat] [#:directories? #f] [#:fail-on-error? #f]
  7612. Return the lexicographically sorted list of files under @var{dir} for
  7613. which @var{pred} returns true. @var{pred} is passed two arguments: the
  7614. absolute file name, and its stat buffer; the default predicate always
  7615. returns true. @var{pred} can also be a regular expression, in which
  7616. case it is equivalent to @code{(file-name-predicate @var{pred})}.
  7617. @var{stat} is used to obtain file information; using @code{lstat} means
  7618. that symlinks are not followed. If @var{directories?} is true, then
  7619. directories will also be included. If @var{fail-on-error?} is true,
  7620. raise an exception upon error.
  7621. @end deffn
  7622. Here are a few examples where we assume that the current directory is
  7623. the root of the Guix source tree:
  7624. @lisp
  7625. ;; List all the regular files in the current directory.
  7626. (find-files ".")
  7627. @result{} ("./.dir-locals.el" "./.gitignore" @dots{})
  7628. ;; List all the .scm files under gnu/services.
  7629. (find-files "gnu/services" "\\.scm$")
  7630. @result{} ("gnu/services/admin.scm" "gnu/services/audio.scm" @dots{})
  7631. ;; List ar files in the current directory.
  7632. (find-files "." (lambda (file stat) (ar-file? file)))
  7633. @result{} ("./libformat.a" "./libstore.a" @dots{})
  7634. @end lisp
  7635. @deffn {Scheme Procedure} which @var{program}
  7636. Return the complete file name for @var{program} as found in
  7637. @code{$PATH}, or @code{#f} if @var{program} could not be found.
  7638. @end deffn
  7639. @deffn {Scheme Procedure} search-input-file @var{inputs} @var{name}
  7640. @deffnx {Scheme Procedure} search-input-directory @var{inputs} @var{name}
  7641. Return the complete file name for @var{name} as found in @var{inputs};
  7642. @code{search-input-file} searches for a regular file and
  7643. @code{search-input-directory} searches for a directory. If @var{name}
  7644. could not be found, an exception is raised.
  7645. Here, @var{inputs} must be an association list like @code{inputs} and
  7646. @code{native-inputs} as available to build phases (@pxref{Build
  7647. Phases}).
  7648. @end deffn
  7649. Here is a (simplified) example of how @code{search-input-file} is used
  7650. in a build phase of the @code{wireguard-tools} package:
  7651. @lisp
  7652. (add-after 'install 'wrap-wg-quick
  7653. (lambda* (#:key inputs outputs #:allow-other-keys)
  7654. (let ((coreutils (string-append (assoc-ref inputs "coreutils")
  7655. "/bin")))
  7656. (wrap-program (search-input-file outputs "bin/wg-quick")
  7657. #:sh (search-input-file inputs "bin/bash")
  7658. `("PATH" ":" prefix ,(list coreutils))))))
  7659. @end lisp
  7660. @subsection Program Invocation
  7661. @cindex program invocation, from Scheme
  7662. @cindex invoking programs, from Scheme
  7663. You'll find handy procedures to spawn processes in this module,
  7664. essentially convenient wrappers around Guile's @code{system*}
  7665. (@pxref{Processes, @code{system*},, guile, GNU Guile Reference Manual}).
  7666. @deffn {Scheme Procedure} invoke @var{program} @var{args}@dots{}
  7667. Invoke @var{program} with the given @var{args}. Raise an
  7668. @code{&invoke-error} exception if the exit code is non-zero; otherwise
  7669. return @code{#t}.
  7670. The advantage compared to @code{system*} is that you do not need to
  7671. check the return value. This reduces boilerplate in shell-script-like
  7672. snippets for instance in package build phases.
  7673. @end deffn
  7674. @deffn {Scheme Procedure} invoke-error? @var{c}
  7675. Return true if @var{c} is an @code{&invoke-error} condition.
  7676. @end deffn
  7677. @deffn {Scheme Procedure} invoke-error-program @var{c}
  7678. @deffnx {Scheme Procedure} invoke-error-arguments @var{c}
  7679. @deffnx {Scheme Procedure} invoke-error-exit-status @var{c}
  7680. @deffnx {Scheme Procedure} invoke-error-term-signal @var{c}
  7681. @deffnx {Scheme Procedure} invoke-error-stop-signal @var{c}
  7682. Access specific fields of @var{c}, an @code{&invoke-error} condition.
  7683. @end deffn
  7684. @deffn {Scheme Procedure} report-invoke-error @var{c} [@var{port}]
  7685. Report to @var{port} (by default the current error port) about @var{c},
  7686. an @code{&invoke-error} condition, in a human-friendly way.
  7687. Typical usage would look like this:
  7688. @lisp
  7689. (use-modules (srfi srfi-34) ;for 'guard'
  7690. (guix build utils))
  7691. (guard (c ((invoke-error? c)
  7692. (report-invoke-error c)))
  7693. (invoke "date" "--imaginary-option"))
  7694. @print{} command "date" "--imaginary-option" failed with status 1
  7695. @end lisp
  7696. @end deffn
  7697. @deffn {Scheme Procedure} invoke/quiet @var{program} @var{args}@dots{}
  7698. Invoke @var{program} with @var{args} and capture @var{program}'s
  7699. standard output and standard error. If @var{program} succeeds, print
  7700. nothing and return the unspecified value; otherwise, raise a
  7701. @code{&message} error condition that includes the status code and the
  7702. output of @var{program}.
  7703. Here's an example:
  7704. @lisp
  7705. (use-modules (srfi srfi-34) ;for 'guard'
  7706. (srfi srfi-35) ;for 'message-condition?'
  7707. (guix build utils))
  7708. (guard (c ((message-condition? c)
  7709. (display (condition-message c))))
  7710. (invoke/quiet "date") ;all is fine
  7711. (invoke/quiet "date" "--imaginary-option"))
  7712. @print{} 'date --imaginary-option' exited with status 1; output follows:
  7713. date: unrecognized option '--imaginary-option'
  7714. Try 'date --help' for more information.
  7715. @end lisp
  7716. @end deffn
  7717. @subsection Build Phases
  7718. @cindex build phases
  7719. The @code{(guix build utils)} also contains tools to manipulate build
  7720. phases as used by build systems (@pxref{Build Systems}). Build phases
  7721. are represented as association lists or ``alists'' (@pxref{Association
  7722. Lists,,, guile, GNU Guile Reference Manual}) where each key is a symbol
  7723. naming the phase and the associated value is a procedure (@pxref{Build
  7724. Phases}).
  7725. Guile core and the @code{(srfi srfi-1)} module both provide tools to
  7726. manipulate alists. The @code{(guix build utils)} module complements
  7727. those with tools written with build phases in mind.
  7728. @cindex build phases, modifying
  7729. @deffn {Scheme Syntax} modify-phases @var{phases} @var{clause}@dots{}
  7730. Modify @var{phases} sequentially as per each @var{clause}, which may
  7731. have one of the following forms:
  7732. @lisp
  7733. (delete @var{old-phase-name})
  7734. (replace @var{old-phase-name} @var{new-phase})
  7735. (add-before @var{old-phase-name} @var{new-phase-name} @var{new-phase})
  7736. (add-after @var{old-phase-name} @var{new-phase-name} @var{new-phase})
  7737. @end lisp
  7738. Where every @var{phase-name} above is an expression evaluating to a
  7739. symbol, and @var{new-phase} an expression evaluating to a procedure.
  7740. @end deffn
  7741. The example below is taken from the definition of the @code{grep}
  7742. package. It adds a phase to run after the @code{install} phase, called
  7743. @code{fix-egrep-and-fgrep}. That phase is a procedure (@code{lambda*}
  7744. is for anonymous procedures) that takes a @code{#:outputs} keyword
  7745. argument and ignores extra keyword arguments (@pxref{Optional
  7746. Arguments,,, guile, GNU Guile Reference Manual}, for more on
  7747. @code{lambda*} and optional and keyword arguments.) The phase uses
  7748. @code{substitute*} to modify the installed @file{egrep} and @file{fgrep}
  7749. scripts so that they refer to @code{grep} by its absolute file name:
  7750. @lisp
  7751. (modify-phases %standard-phases
  7752. (add-after 'install 'fix-egrep-and-fgrep
  7753. ;; Patch 'egrep' and 'fgrep' to execute 'grep' via its
  7754. ;; absolute file name instead of searching for it in $PATH.
  7755. (lambda* (#:key outputs #:allow-other-keys)
  7756. (let* ((out (assoc-ref outputs "out"))
  7757. (bin (string-append out "/bin")))
  7758. (substitute* (list (string-append bin "/egrep")
  7759. (string-append bin "/fgrep"))
  7760. (("^exec grep")
  7761. (string-append "exec " bin "/grep")))))))
  7762. @end lisp
  7763. In the example below, phases are modified in two ways: the standard
  7764. @code{configure} phase is deleted, presumably because the package does
  7765. not have a @file{configure} script or anything similar, and the default
  7766. @code{install} phase is replaced by one that manually copies the
  7767. executable files to be installed:
  7768. @lisp
  7769. (modify-phases %standard-phases
  7770. (delete 'configure) ;no 'configure' script
  7771. (replace 'install
  7772. (lambda* (#:key outputs #:allow-other-keys)
  7773. ;; The package's Makefile doesn't provide an "install"
  7774. ;; rule so do it by ourselves.
  7775. (let ((bin (string-append (assoc-ref outputs "out")
  7776. "/bin")))
  7777. (install-file "footswitch" bin)
  7778. (install-file "scythe" bin)))))
  7779. @end lisp
  7780. @c TODO: Add more examples.
  7781. @subsection Wrappers
  7782. @cindex program wrappers
  7783. @cindex wrapping programs
  7784. It is not unusual for a command to require certain environment variables
  7785. to be set for proper functioning, typically search paths (@pxref{Search
  7786. Paths}). Failing to do that, the command might fail to find files or
  7787. other commands it relies on, or it might pick the ``wrong''
  7788. ones---depending on the environment in which it runs. Examples include:
  7789. @itemize
  7790. @item
  7791. a shell script that assumes all the commands it uses are in @env{PATH};
  7792. @item
  7793. a Guile program that assumes all its modules are in @env{GUILE_LOAD_PATH}
  7794. and @env{GUILE_LOAD_COMPILED_PATH};
  7795. @item
  7796. a Qt application that expects to find certain plugins in
  7797. @env{QT_PLUGIN_PATH}.
  7798. @end itemize
  7799. For a package writer, the goal is to make sure commands always work the
  7800. same rather than depend on some external settings. One way to achieve
  7801. that is to @dfn{wrap} commands in a thin script that sets those
  7802. environment variables, thereby ensuring that those run-time dependencies
  7803. are always found. The wrapper would be used to set @env{PATH},
  7804. @env{GUILE_LOAD_PATH}, or @env{QT_PLUGIN_PATH} in the examples above.
  7805. To ease that task, the @code{(guix build utils)} module provides a
  7806. couple of helpers to wrap commands.
  7807. @deffn {Scheme Procedure} wrap-program @var{program} @
  7808. [#:sh @var{sh}] [#:rest @var{variables}]
  7809. Make a wrapper for @var{program}. @var{variables} should look like this:
  7810. @lisp
  7811. '(@var{variable} @var{delimiter} @var{position} @var{list-of-directories})
  7812. @end lisp
  7813. where @var{delimiter} is optional. @code{:} will be used if
  7814. @var{delimiter} is not given.
  7815. For example, this call:
  7816. @lisp
  7817. (wrap-program "foo"
  7818. '("PATH" ":" = ("/gnu/.../bar/bin"))
  7819. '("CERT_PATH" suffix ("/gnu/.../baz/certs"
  7820. "/qux/certs")))
  7821. @end lisp
  7822. will copy @file{foo} to @file{.foo-real} and create the file @file{foo}
  7823. with the following contents:
  7824. @example
  7825. #!location/of/bin/bash
  7826. export PATH="/gnu/.../bar/bin"
  7827. export CERT_PATH="$CERT_PATH$@{CERT_PATH:+:@}/gnu/.../baz/certs:/qux/certs"
  7828. exec -a $0 location/of/.foo-real "$@@"
  7829. @end example
  7830. If @var{program} has previously been wrapped by @code{wrap-program}, the
  7831. wrapper is extended with definitions for @var{variables}. If it is not,
  7832. @var{sh} will be used as the interpreter.
  7833. @end deffn
  7834. @deffn {Scheme Procedure} wrap-script @var{program} @
  7835. [#:guile @var{guile}] [#:rest @var{variables}]
  7836. Wrap the script @var{program} such that @var{variables} are set first.
  7837. The format of @var{variables} is the same as in the @code{wrap-program}
  7838. procedure. This procedure differs from @code{wrap-program} in that it
  7839. does not create a separate shell script. Instead, @var{program} is
  7840. modified directly by prepending a Guile script, which is interpreted as
  7841. a comment in the script's language.
  7842. Special encoding comments as supported by Python are recreated on the
  7843. second line.
  7844. Note that this procedure can only be used once per file as Guile scripts are
  7845. not supported.
  7846. @end deffn
  7847. @node Search Paths
  7848. @section Search Paths
  7849. @cindex search path
  7850. Many programs and libraries look for input data in a @dfn{search path},
  7851. a list of directories: shells like Bash look for executables in the
  7852. command search path, a C compiler looks for @file{.h} files in its
  7853. header search path, the Python interpreter looks for @file{.py}
  7854. files in its search path, the spell checker has a search path for
  7855. dictionaries, and so on.
  7856. Search paths can usually be defined or overridden @i{via} environment
  7857. variables (@pxref{Environment Variables,,, libc, The GNU C Library
  7858. Reference Manual}). For example, the search paths mentioned above can
  7859. be changed by defining the @env{PATH}, @env{C_INCLUDE_PATH},
  7860. @env{PYTHONPATH} (or @env{GUIX_PYTHONPATH}), and @env{DICPATH}
  7861. environment variables---you know, all these something-PATH variables
  7862. that you need to get right or things ``won't be found''.
  7863. You may have noticed from the command line that Guix ``knows'' which
  7864. search path environment variables should be defined, and how. When you
  7865. install packages in your default profile, the file
  7866. @file{~/.guix-profile/etc/profile} is created, which you can ``source''
  7867. from the shell to set those variables. Likewise, if you ask
  7868. @command{guix shell} to create an environment containing Python and
  7869. NumPy, a Python library, and if you pass it the @option{--search-paths}
  7870. option, it will tell you about @env{PATH} and @env{GUIX_PYTHONPATH}
  7871. (@pxref{Invoking guix shell}):
  7872. @example
  7873. $ guix shell python python-numpy --pure --search-paths
  7874. export PATH="/gnu/store/@dots{}-profile/bin"
  7875. export GUIX_PYTHONPATH="/gnu/store/@dots{}-profile/lib/python3.9/site-packages"
  7876. @end example
  7877. When you omit @option{--search-paths}, it defines these environment
  7878. variables right away, such that Python can readily find NumPy:
  7879. @example
  7880. $ guix shell python python-numpy -- python3
  7881. Python 3.9.6 (default, Jan 1 1970, 00:00:01)
  7882. [GCC 10.3.0] on linux
  7883. Type "help", "copyright", "credits" or "license" for more information.
  7884. >>> import numpy
  7885. >>> numpy.version.version
  7886. '1.20.3'
  7887. @end example
  7888. For this to work, the definition of the @code{python} package
  7889. @emph{declares} the search path it cares about and its associated
  7890. environment variable, @env{GUIX_PYTHONPATH}. It looks like this:
  7891. @lisp
  7892. (package
  7893. (name "python")
  7894. (version "3.9.9")
  7895. ;; some fields omitted...
  7896. (native-search-paths
  7897. (list (search-path-specification
  7898. (variable "GUIX_PYTHONPATH")
  7899. (files (list "lib/python/3.9/site-packages"))))))
  7900. @end lisp
  7901. What this @code{native-search-paths} field says is that, when the
  7902. @code{python} package is used, the @env{GUIX_PYTHONPATH} environment
  7903. variable must be defined to include all the
  7904. @file{lib/python/3.9/site-packages} sub-directories encountered in its
  7905. environment. (The @code{native-} bit means that, if we are in a
  7906. cross-compilation environment, only native inputs may be added to the
  7907. search path; @pxref{package Reference, @code{search-paths}}.)
  7908. In the NumPy example above, the profile where
  7909. @code{python} appears contains exactly one such sub-directory, and
  7910. @env{GUIX_PYTHONPATH} is set to that. When there are several
  7911. @file{lib/python/3.9/site-packages}---this is the case in package build
  7912. environments---they are all added to @env{GUIX_PYTHONPATH}, separated by
  7913. colons (@code{:}).
  7914. @quotation Note
  7915. Notice that @env{GUIX_PYTHONPATH} is specified as part of the definition
  7916. of the @code{python} package, and @emph{not} as part of that of
  7917. @code{python-numpy}. This is because this environment variable
  7918. ``belongs'' to Python, not NumPy: Python actually reads the value of
  7919. that variable and honors it.
  7920. Corollary: if you create a profile that does not contain @code{python},
  7921. @code{GUIX_PYTHONPATH} will @emph{not} be defined, even if it contains
  7922. packages that provide @file{.py} files:
  7923. @example
  7924. $ guix shell python-numpy --search-paths --pure
  7925. export PATH="/gnu/store/@dots{}-profile/bin"
  7926. @end example
  7927. This makes a lot of sense if we look at this profile in isolation: no
  7928. software in this profile would read @env{GUIX_PYTHONPATH}.
  7929. @end quotation
  7930. Of course, there are many variations on that theme: some packages honor
  7931. more than one search path, some use separators other than colon, some
  7932. accumulate several directories in their search path, and so on. A more
  7933. complex example is the search path of libxml2: the value of the
  7934. @env{XML_CATALOG_FILES} environment variable is space-separated, it must
  7935. contain a list of @file{catalog.xml} files (not directories), which are
  7936. to be found in @file{xml} sub-directories---nothing less. The search
  7937. path specification looks like this:
  7938. @lisp
  7939. (package
  7940. (name "libxml2")
  7941. ;; some fields omitted
  7942. (native-search-paths
  7943. (list (search-path-specification
  7944. (variable "XML_CATALOG_FILES")
  7945. (separator " ")
  7946. (files '("xml"))
  7947. (file-pattern "^catalog\\.xml$")
  7948. (file-type 'regular)))))
  7949. @end lisp
  7950. Worry not, search path specifications are usually not this tricky.
  7951. The @code{(guix search-paths)} module defines the data type of search
  7952. path specifications and a number of helper procedures. Below is the
  7953. reference of search path specifications.
  7954. @deftp {Data Type} search-path-specification
  7955. The data type for search path specifications.
  7956. @table @asis
  7957. @item @code{variable}
  7958. The name of the environment variable for this search path (a string).
  7959. @item @code{files}
  7960. The list of sub-directories (strings) that should be added to the search
  7961. path.
  7962. @item @code{separator} (default: @code{":"})
  7963. The string used to separate search path components.
  7964. As a special case, a @code{separator} value of @code{#f} specifies a
  7965. ``single-component search path''---in other words, a search path that
  7966. cannot contain more than one element. This is useful in some cases,
  7967. such as the @code{SSL_CERT_DIR} variable (honored by OpenSSL, cURL, and
  7968. a few other packages) or the @code{ASPELL_DICT_DIR} variable (honored by
  7969. the GNU Aspell spell checker), both of which must point to a single
  7970. directory.
  7971. @item @code{file-type} (default: @code{'directory})
  7972. The type of file being matched---@code{'directory} or @code{'regular},
  7973. though it can be any symbol returned by @code{stat:type} (@pxref{File
  7974. System, @code{stat},, guile, GNU Guile Reference Manual}).
  7975. In the libxml2 example above, we would match regular files; in the
  7976. Python example, we would match directories.
  7977. @item @code{file-pattern} (default: @code{#f})
  7978. This must be either @code{#f} or a regular expression specifying
  7979. files to be matched @emph{within} the sub-directories specified by the
  7980. @code{files} field.
  7981. Again, the libxml2 example shows a situation where this is needed.
  7982. @end table
  7983. @end deftp
  7984. How do you turn search path specifications on one hand and a bunch of
  7985. directories on the other hand in a set of environment variable
  7986. definitions? That's the job of @code{evaluate-search-paths}.
  7987. @deffn {Scheme Procedure} evaluate-search-paths @var{search-paths} @
  7988. @var{directories} [@var{getenv}]
  7989. Evaluate @var{search-paths}, a list of search-path specifications, for
  7990. @var{directories}, a list of directory names, and return a list of
  7991. specification/value pairs. Use @var{getenv} to determine the current
  7992. settings and report only settings not already effective.
  7993. @end deffn
  7994. The @code{(guix profiles)} provides a higher-level helper procedure,
  7995. @code{load-profile}, that sets the environment variables of a profile.
  7996. @node The Store
  7997. @section The Store
  7998. @cindex store
  7999. @cindex store items
  8000. @cindex store paths
  8001. Conceptually, the @dfn{store} is the place where derivations that have
  8002. been built successfully are stored---by default, @file{/gnu/store}.
  8003. Sub-directories in the store are referred to as @dfn{store items} or
  8004. sometimes @dfn{store paths}. The store has an associated database that
  8005. contains information such as the store paths referred to by each store
  8006. path, and the list of @emph{valid} store items---results of successful
  8007. builds. This database resides in @file{@var{localstatedir}/guix/db},
  8008. where @var{localstatedir} is the state directory specified @i{via}
  8009. @option{--localstatedir} at configure time, usually @file{/var}.
  8010. The store is @emph{always} accessed by the daemon on behalf of its clients
  8011. (@pxref{Invoking guix-daemon}). To manipulate the store, clients
  8012. connect to the daemon over a Unix-domain socket, send requests to it,
  8013. and read the result---these are remote procedure calls, or RPCs.
  8014. @quotation Note
  8015. Users must @emph{never} modify files under @file{/gnu/store} directly.
  8016. This would lead to inconsistencies and break the immutability
  8017. assumptions of Guix's functional model (@pxref{Introduction}).
  8018. @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
  8019. how to check the integrity of the store and attempt recovery from
  8020. accidental modifications.
  8021. @end quotation
  8022. The @code{(guix store)} module provides procedures to connect to the
  8023. daemon, and to perform RPCs. These are described below. By default,
  8024. @code{open-connection}, and thus all the @command{guix} commands,
  8025. connect to the local daemon or to the URI specified by the
  8026. @env{GUIX_DAEMON_SOCKET} environment variable.
  8027. @defvr {Environment Variable} GUIX_DAEMON_SOCKET
  8028. When set, the value of this variable should be a file name or a URI
  8029. designating the daemon endpoint. When it is a file name, it denotes a
  8030. Unix-domain socket to connect to. In addition to file names, the
  8031. supported URI schemes are:
  8032. @table @code
  8033. @item file
  8034. @itemx unix
  8035. These are for Unix-domain sockets.
  8036. @code{file:///var/guix/daemon-socket/socket} is equivalent to
  8037. @file{/var/guix/daemon-socket/socket}.
  8038. @item guix
  8039. @cindex daemon, remote access
  8040. @cindex remote access to the daemon
  8041. @cindex daemon, cluster setup
  8042. @cindex clusters, daemon setup
  8043. These URIs denote connections over TCP/IP, without encryption nor
  8044. authentication of the remote host. The URI must specify the host name
  8045. and optionally a port number (by default port 44146 is used):
  8046. @example
  8047. guix://master.guix.example.org:1234
  8048. @end example
  8049. This setup is suitable on local networks, such as clusters, where only
  8050. trusted nodes may connect to the build daemon at
  8051. @code{master.guix.example.org}.
  8052. The @option{--listen} option of @command{guix-daemon} can be used to
  8053. instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
  8054. @option{--listen}}).
  8055. @item ssh
  8056. @cindex SSH access to build daemons
  8057. These URIs allow you to connect to a remote daemon over SSH@. This
  8058. feature requires Guile-SSH (@pxref{Requirements}) and a working
  8059. @command{guile} binary in @env{PATH} on the destination machine. It
  8060. supports public key and GSSAPI authentication. A typical URL might look
  8061. like this:
  8062. @example
  8063. ssh://charlie@@guix.example.org:22
  8064. @end example
  8065. As for @command{guix copy}, the usual OpenSSH client configuration files
  8066. are honored (@pxref{Invoking guix copy}).
  8067. @end table
  8068. Additional URI schemes may be supported in the future.
  8069. @c XXX: Remove this note when the protocol incurs fewer round trips
  8070. @c and when (guix derivations) no longer relies on file system access.
  8071. @quotation Note
  8072. The ability to connect to remote build daemons is considered
  8073. experimental as of @value{VERSION}. Please get in touch with us to
  8074. share any problems or suggestions you may have (@pxref{Contributing}).
  8075. @end quotation
  8076. @end defvr
  8077. @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
  8078. Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
  8079. @var{reserve-space?} is true, instruct it to reserve a little bit of
  8080. extra space on the file system so that the garbage collector can still
  8081. operate should the disk become full. Return a server object.
  8082. @var{file} defaults to @code{%default-socket-path}, which is the normal
  8083. location given the options that were passed to @command{configure}.
  8084. @end deffn
  8085. @deffn {Scheme Procedure} close-connection @var{server}
  8086. Close the connection to @var{server}.
  8087. @end deffn
  8088. @defvr {Scheme Variable} current-build-output-port
  8089. This variable is bound to a SRFI-39 parameter, which refers to the port
  8090. where build and error logs sent by the daemon should be written.
  8091. @end defvr
  8092. Procedures that make RPCs all take a server object as their first
  8093. argument.
  8094. @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
  8095. @cindex invalid store items
  8096. Return @code{#t} when @var{path} designates a valid store item and
  8097. @code{#f} otherwise (an invalid item may exist on disk but still be
  8098. invalid, for instance because it is the result of an aborted or failed
  8099. build).
  8100. A @code{&store-protocol-error} condition is raised if @var{path} is not
  8101. prefixed by the store directory (@file{/gnu/store}).
  8102. @end deffn
  8103. @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
  8104. Add @var{text} under file @var{name} in the store, and return its store
  8105. path. @var{references} is the list of store paths referred to by the
  8106. resulting store path.
  8107. @end deffn
  8108. @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
  8109. [@var{mode}]
  8110. Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
  8111. file names, or derivation/output pairs, using the specified
  8112. @var{mode}---@code{(build-mode normal)} by default.
  8113. @end deffn
  8114. Note that the @code{(guix monads)} module provides a monad as well as
  8115. monadic versions of the above procedures, with the goal of making it
  8116. more convenient to work with code that accesses the store (@pxref{The
  8117. Store Monad}).
  8118. @c FIXME
  8119. @i{This section is currently incomplete.}
  8120. @node Derivations
  8121. @section Derivations
  8122. @cindex derivations
  8123. Low-level build actions and the environment in which they are performed
  8124. are represented by @dfn{derivations}. A derivation contains the
  8125. following pieces of information:
  8126. @itemize
  8127. @item
  8128. The outputs of the derivation---derivations produce at least one file or
  8129. directory in the store, but may produce more.
  8130. @item
  8131. @cindex build-time dependencies
  8132. @cindex dependencies, build-time
  8133. The inputs of the derivations---i.e., its build-time dependencies---which may
  8134. be other derivations or plain files in the store (patches, build scripts,
  8135. etc.).
  8136. @item
  8137. The system type targeted by the derivation---e.g., @code{x86_64-linux}.
  8138. @item
  8139. The file name of a build script in the store, along with the arguments
  8140. to be passed.
  8141. @item
  8142. A list of environment variables to be defined.
  8143. @end itemize
  8144. @cindex derivation path
  8145. Derivations allow clients of the daemon to communicate build actions to
  8146. the store. They exist in two forms: as an in-memory representation,
  8147. both on the client- and daemon-side, and as files in the store whose
  8148. name end in @file{.drv}---these files are referred to as @dfn{derivation
  8149. paths}. Derivations paths can be passed to the @code{build-derivations}
  8150. procedure to perform the build actions they prescribe (@pxref{The
  8151. Store}).
  8152. @cindex fixed-output derivations
  8153. Operations such as file downloads and version-control checkouts for
  8154. which the expected content hash is known in advance are modeled as
  8155. @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
  8156. of a fixed-output derivation are independent of its inputs---e.g., a
  8157. source code download produces the same result regardless of the download
  8158. method and tools being used.
  8159. @cindex references
  8160. @cindex run-time dependencies
  8161. @cindex dependencies, run-time
  8162. The outputs of derivations---i.e., the build results---have a set of
  8163. @dfn{references}, as reported by the @code{references} RPC or the
  8164. @command{guix gc --references} command (@pxref{Invoking guix gc}). References
  8165. are the set of run-time dependencies of the build results. References are a
  8166. subset of the inputs of the derivation; this subset is automatically computed
  8167. by the build daemon by scanning all the files in the outputs.
  8168. The @code{(guix derivations)} module provides a representation of
  8169. derivations as Scheme objects, along with procedures to create and
  8170. otherwise manipulate derivations. The lowest-level primitive to create
  8171. a derivation is the @code{derivation} procedure:
  8172. @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
  8173. @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
  8174. [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
  8175. [#:system (%current-system)] [#:references-graphs #f] @
  8176. [#:allowed-references #f] [#:disallowed-references #f] @
  8177. [#:leaked-env-vars #f] [#:local-build? #f] @
  8178. [#:substitutable? #t] [#:properties '()]
  8179. Build a derivation with the given arguments, and return the resulting
  8180. @code{<derivation>} object.
  8181. When @var{hash} and @var{hash-algo} are given, a
  8182. @dfn{fixed-output derivation} is created---i.e., one whose result is
  8183. known in advance, such as a file download. If, in addition,
  8184. @var{recursive?} is true, then that fixed output may be an executable
  8185. file or a directory and @var{hash} must be the hash of an archive
  8186. containing this output.
  8187. When @var{references-graphs} is true, it must be a list of file
  8188. name/store path pairs. In that case, the reference graph of each store
  8189. path is exported in the build environment in the corresponding file, in
  8190. a simple text format.
  8191. When @var{allowed-references} is true, it must be a list of store items
  8192. or outputs that the derivation's output may refer to. Likewise,
  8193. @var{disallowed-references}, if true, must be a list of things the
  8194. outputs may @emph{not} refer to.
  8195. When @var{leaked-env-vars} is true, it must be a list of strings
  8196. denoting environment variables that are allowed to ``leak'' from the
  8197. daemon's environment to the build environment. This is only applicable
  8198. to fixed-output derivations---i.e., when @var{hash} is true. The main
  8199. use is to allow variables such as @code{http_proxy} to be passed to
  8200. derivations that download files.
  8201. When @var{local-build?} is true, declare that the derivation is not a
  8202. good candidate for offloading and should rather be built locally
  8203. (@pxref{Daemon Offload Setup}). This is the case for small derivations
  8204. where the costs of data transfers would outweigh the benefits.
  8205. When @var{substitutable?} is false, declare that substitutes of the
  8206. derivation's output should not be used (@pxref{Substitutes}). This is
  8207. useful, for instance, when building packages that capture details of the
  8208. host CPU instruction set.
  8209. @var{properties} must be an association list describing ``properties'' of the
  8210. derivation. It is kept as-is, uninterpreted, in the derivation.
  8211. @end deffn
  8212. @noindent
  8213. Here's an example with a shell script as its builder, assuming
  8214. @var{store} is an open connection to the daemon, and @var{bash} points
  8215. to a Bash executable in the store:
  8216. @lisp
  8217. (use-modules (guix utils)
  8218. (guix store)
  8219. (guix derivations))
  8220. (let ((builder ; add the Bash script to the store
  8221. (add-text-to-store store "my-builder.sh"
  8222. "echo hello world > $out\n" '())))
  8223. (derivation store "foo"
  8224. bash `("-e" ,builder)
  8225. #:inputs `((,bash) (,builder))
  8226. #:env-vars '(("HOME" . "/homeless"))))
  8227. @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
  8228. @end lisp
  8229. As can be guessed, this primitive is cumbersome to use directly. A
  8230. better approach is to write build scripts in Scheme, of course! The
  8231. best course of action for that is to write the build code as a
  8232. ``G-expression'', and to pass it to @code{gexp->derivation}. For more
  8233. information, @pxref{G-Expressions}.
  8234. Once upon a time, @code{gexp->derivation} did not exist and constructing
  8235. derivations with build code written in Scheme was achieved with
  8236. @code{build-expression->derivation}, documented below. This procedure
  8237. is now deprecated in favor of the much nicer @code{gexp->derivation}.
  8238. @deffn {Scheme Procedure} build-expression->derivation @var{store} @
  8239. @var{name} @var{exp} @
  8240. [#:system (%current-system)] [#:inputs '()] @
  8241. [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
  8242. [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
  8243. [#:references-graphs #f] [#:allowed-references #f] @
  8244. [#:disallowed-references #f] @
  8245. [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
  8246. Return a derivation that executes Scheme expression @var{exp} as a
  8247. builder for derivation @var{name}. @var{inputs} must be a list of
  8248. @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
  8249. @code{"out"} is assumed. @var{modules} is a list of names of Guile
  8250. modules from the current search path to be copied in the store,
  8251. compiled, and made available in the load path during the execution of
  8252. @var{exp}---e.g., @code{((guix build utils) (guix build
  8253. gnu-build-system))}.
  8254. @var{exp} is evaluated in an environment where @code{%outputs} is bound
  8255. to a list of output/path pairs, and where @code{%build-inputs} is bound
  8256. to a list of string/output-path pairs made from @var{inputs}.
  8257. Optionally, @var{env-vars} is a list of string pairs specifying the name
  8258. and value of environment variables visible to the builder. The builder
  8259. terminates by passing the result of @var{exp} to @code{exit}; thus, when
  8260. @var{exp} returns @code{#f}, the build is considered to have failed.
  8261. @var{exp} is built using @var{guile-for-build} (a derivation). When
  8262. @var{guile-for-build} is omitted or is @code{#f}, the value of the
  8263. @code{%guile-for-build} fluid is used instead.
  8264. See the @code{derivation} procedure for the meaning of
  8265. @var{references-graphs}, @var{allowed-references},
  8266. @var{disallowed-references}, @var{local-build?}, and
  8267. @var{substitutable?}.
  8268. @end deffn
  8269. @noindent
  8270. Here's an example of a single-output derivation that creates a directory
  8271. containing one file:
  8272. @lisp
  8273. (let ((builder '(let ((out (assoc-ref %outputs "out")))
  8274. (mkdir out) ; create /gnu/store/@dots{}-goo
  8275. (call-with-output-file (string-append out "/test")
  8276. (lambda (p)
  8277. (display '(hello guix) p))))))
  8278. (build-expression->derivation store "goo" builder))
  8279. @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
  8280. @end lisp
  8281. @node The Store Monad
  8282. @section The Store Monad
  8283. @cindex monad
  8284. The procedures that operate on the store described in the previous
  8285. sections all take an open connection to the build daemon as their first
  8286. argument. Although the underlying model is functional, they either have
  8287. side effects or depend on the current state of the store.
  8288. The former is inconvenient: the connection to the build daemon has to be
  8289. carried around in all those functions, making it impossible to compose
  8290. functions that do not take that parameter with functions that do. The
  8291. latter can be problematic: since store operations have side effects
  8292. and/or depend on external state, they have to be properly sequenced.
  8293. @cindex monadic values
  8294. @cindex monadic functions
  8295. This is where the @code{(guix monads)} module comes in. This module
  8296. provides a framework for working with @dfn{monads}, and a particularly
  8297. useful monad for our uses, the @dfn{store monad}. Monads are a
  8298. construct that allows two things: associating ``context'' with values
  8299. (in our case, the context is the store), and building sequences of
  8300. computations (here computations include accesses to the store). Values
  8301. in a monad---values that carry this additional context---are called
  8302. @dfn{monadic values}; procedures that return such values are called
  8303. @dfn{monadic procedures}.
  8304. Consider this ``normal'' procedure:
  8305. @lisp
  8306. (define (sh-symlink store)
  8307. ;; Return a derivation that symlinks the 'bash' executable.
  8308. (let* ((drv (package-derivation store bash))
  8309. (out (derivation->output-path drv))
  8310. (sh (string-append out "/bin/bash")))
  8311. (build-expression->derivation store "sh"
  8312. `(symlink ,sh %output))))
  8313. @end lisp
  8314. Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
  8315. as a monadic function:
  8316. @lisp
  8317. (define (sh-symlink)
  8318. ;; Same, but return a monadic value.
  8319. (mlet %store-monad ((drv (package->derivation bash)))
  8320. (gexp->derivation "sh"
  8321. #~(symlink (string-append #$drv "/bin/bash")
  8322. #$output))))
  8323. @end lisp
  8324. There are several things to note in the second version: the @code{store}
  8325. parameter is now implicit and is ``threaded'' in the calls to the
  8326. @code{package->derivation} and @code{gexp->derivation} monadic
  8327. procedures, and the monadic value returned by @code{package->derivation}
  8328. is @dfn{bound} using @code{mlet} instead of plain @code{let}.
  8329. As it turns out, the call to @code{package->derivation} can even be
  8330. omitted since it will take place implicitly, as we will see later
  8331. (@pxref{G-Expressions}):
  8332. @lisp
  8333. (define (sh-symlink)
  8334. (gexp->derivation "sh"
  8335. #~(symlink (string-append #$bash "/bin/bash")
  8336. #$output)))
  8337. @end lisp
  8338. @c See
  8339. @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
  8340. @c for the funny quote.
  8341. Calling the monadic @code{sh-symlink} has no effect. As someone once
  8342. said, ``you exit a monad like you exit a building on fire: by running''.
  8343. So, to exit the monad and get the desired effect, one must use
  8344. @code{run-with-store}:
  8345. @lisp
  8346. (run-with-store (open-connection) (sh-symlink))
  8347. @result{} /gnu/store/...-sh-symlink
  8348. @end lisp
  8349. Note that the @code{(guix monad-repl)} module extends the Guile REPL with
  8350. new ``meta-commands'' to make it easier to deal with monadic procedures:
  8351. @code{run-in-store}, and @code{enter-store-monad}. The former is used
  8352. to ``run'' a single monadic value through the store:
  8353. @example
  8354. scheme@@(guile-user)> ,run-in-store (package->derivation hello)
  8355. $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
  8356. @end example
  8357. The latter enters a recursive REPL, where all the return values are
  8358. automatically run through the store:
  8359. @example
  8360. scheme@@(guile-user)> ,enter-store-monad
  8361. store-monad@@(guile-user) [1]> (package->derivation hello)
  8362. $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
  8363. store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
  8364. $3 = "/gnu/store/@dots{}-foo"
  8365. store-monad@@(guile-user) [1]> ,q
  8366. scheme@@(guile-user)>
  8367. @end example
  8368. @noindent
  8369. Note that non-monadic values cannot be returned in the
  8370. @code{store-monad} REPL.
  8371. The main syntactic forms to deal with monads in general are provided by
  8372. the @code{(guix monads)} module and are described below.
  8373. @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
  8374. Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
  8375. in @var{monad}.
  8376. @end deffn
  8377. @deffn {Scheme Syntax} return @var{val}
  8378. Return a monadic value that encapsulates @var{val}.
  8379. @end deffn
  8380. @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
  8381. @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
  8382. procedures @var{mproc}@dots{}@footnote{This operation is commonly
  8383. referred to as ``bind'', but that name denotes an unrelated procedure in
  8384. Guile. Thus we use this somewhat cryptic symbol inherited from the
  8385. Haskell language.}. There can be one @var{mproc} or several of them, as
  8386. in this example:
  8387. @lisp
  8388. (run-with-state
  8389. (with-monad %state-monad
  8390. (>>= (return 1)
  8391. (lambda (x) (return (+ 1 x)))
  8392. (lambda (x) (return (* 2 x)))))
  8393. 'some-state)
  8394. @result{} 4
  8395. @result{} some-state
  8396. @end lisp
  8397. @end deffn
  8398. @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
  8399. @var{body} ...
  8400. @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
  8401. @var{body} ...
  8402. Bind the variables @var{var} to the monadic values @var{mval} in
  8403. @var{body}, which is a sequence of expressions. As with the bind
  8404. operator, this can be thought of as ``unpacking'' the raw, non-monadic
  8405. value ``contained'' in @var{mval} and making @var{var} refer to that
  8406. raw, non-monadic value within the scope of the @var{body}. The form
  8407. (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
  8408. @var{val}, as per @code{let}. The binding operations occur in sequence
  8409. from left to right. The last expression of @var{body} must be a monadic
  8410. expression, and its result will become the result of the @code{mlet} or
  8411. @code{mlet*} when run in the @var{monad}.
  8412. @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
  8413. (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
  8414. @end deffn
  8415. @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
  8416. Bind @var{mexp} and the following monadic expressions in sequence,
  8417. returning the result of the last expression. Every expression in the
  8418. sequence must be a monadic expression.
  8419. This is akin to @code{mlet}, except that the return values of the
  8420. monadic expressions are ignored. In that sense, it is analogous to
  8421. @code{begin}, but applied to monadic expressions.
  8422. @end deffn
  8423. @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
  8424. When @var{condition} is true, evaluate the sequence of monadic
  8425. expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
  8426. @var{condition} is false, return @code{*unspecified*} in the current
  8427. monad. Every expression in the sequence must be a monadic expression.
  8428. @end deffn
  8429. @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
  8430. When @var{condition} is false, evaluate the sequence of monadic
  8431. expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
  8432. @var{condition} is true, return @code{*unspecified*} in the current
  8433. monad. Every expression in the sequence must be a monadic expression.
  8434. @end deffn
  8435. @cindex state monad
  8436. The @code{(guix monads)} module provides the @dfn{state monad}, which
  8437. allows an additional value---the state---to be @emph{threaded} through
  8438. monadic procedure calls.
  8439. @defvr {Scheme Variable} %state-monad
  8440. The state monad. Procedures in the state monad can access and change
  8441. the state that is threaded.
  8442. Consider the example below. The @code{square} procedure returns a value
  8443. in the state monad. It returns the square of its argument, but also
  8444. increments the current state value:
  8445. @lisp
  8446. (define (square x)
  8447. (mlet %state-monad ((count (current-state)))
  8448. (mbegin %state-monad
  8449. (set-current-state (+ 1 count))
  8450. (return (* x x)))))
  8451. (run-with-state (sequence %state-monad (map square (iota 3))) 0)
  8452. @result{} (0 1 4)
  8453. @result{} 3
  8454. @end lisp
  8455. When ``run'' through @code{%state-monad}, we obtain that additional state
  8456. value, which is the number of @code{square} calls.
  8457. @end defvr
  8458. @deffn {Monadic Procedure} current-state
  8459. Return the current state as a monadic value.
  8460. @end deffn
  8461. @deffn {Monadic Procedure} set-current-state @var{value}
  8462. Set the current state to @var{value} and return the previous state as a
  8463. monadic value.
  8464. @end deffn
  8465. @deffn {Monadic Procedure} state-push @var{value}
  8466. Push @var{value} to the current state, which is assumed to be a list,
  8467. and return the previous state as a monadic value.
  8468. @end deffn
  8469. @deffn {Monadic Procedure} state-pop
  8470. Pop a value from the current state and return it as a monadic value.
  8471. The state is assumed to be a list.
  8472. @end deffn
  8473. @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
  8474. Run monadic value @var{mval} starting with @var{state} as the initial
  8475. state. Return two values: the resulting value, and the resulting state.
  8476. @end deffn
  8477. The main interface to the store monad, provided by the @code{(guix
  8478. store)} module, is as follows.
  8479. @defvr {Scheme Variable} %store-monad
  8480. The store monad---an alias for @code{%state-monad}.
  8481. Values in the store monad encapsulate accesses to the store. When its
  8482. effect is needed, a value of the store monad must be ``evaluated'' by
  8483. passing it to the @code{run-with-store} procedure (see below).
  8484. @end defvr
  8485. @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
  8486. Run @var{mval}, a monadic value in the store monad, in @var{store}, an
  8487. open store connection.
  8488. @end deffn
  8489. @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
  8490. Return as a monadic value the absolute file name in the store of the file
  8491. containing @var{text}, a string. @var{references} is a list of store items that the
  8492. resulting text file refers to; it defaults to the empty list.
  8493. @end deffn
  8494. @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
  8495. Return as a monadic value the absolute file name in the store of the file
  8496. containing @var{data}, a bytevector. @var{references} is a list of store
  8497. items that the resulting binary file refers to; it defaults to the empty list.
  8498. @end deffn
  8499. @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
  8500. [#:recursive? #t] [#:select? (const #t)]
  8501. Return the name of @var{file} once interned in the store. Use
  8502. @var{name} as its store name, or the basename of @var{file} if
  8503. @var{name} is omitted.
  8504. When @var{recursive?} is true, the contents of @var{file} are added
  8505. recursively; if @var{file} designates a flat file and @var{recursive?}
  8506. is true, its contents are added, and its permission bits are kept.
  8507. When @var{recursive?} is true, call @code{(@var{select?} @var{file}
  8508. @var{stat})} for each directory entry, where @var{file} is the entry's
  8509. absolute file name and @var{stat} is the result of @code{lstat}; exclude
  8510. entries for which @var{select?} does not return true.
  8511. The example below adds a file to the store, under two different names:
  8512. @lisp
  8513. (run-with-store (open-connection)
  8514. (mlet %store-monad ((a (interned-file "README"))
  8515. (b (interned-file "README" "LEGU-MIN")))
  8516. (return (list a b))))
  8517. @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
  8518. @end lisp
  8519. @end deffn
  8520. The @code{(guix packages)} module exports the following package-related
  8521. monadic procedures:
  8522. @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
  8523. [#:system (%current-system)] [#:target #f] @
  8524. [#:output "out"]
  8525. Return as a monadic
  8526. value in the absolute file name of @var{file} within the @var{output}
  8527. directory of @var{package}. When @var{file} is omitted, return the name
  8528. of the @var{output} directory of @var{package}. When @var{target} is
  8529. true, use it as a cross-compilation target triplet.
  8530. Note that this procedure does @emph{not} build @var{package}. Thus, the
  8531. result might or might not designate an existing file. We recommend not
  8532. using this procedure unless you know what you are doing.
  8533. @end deffn
  8534. @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
  8535. @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
  8536. @var{target} [@var{system}]
  8537. Monadic version of @code{package-derivation} and
  8538. @code{package-cross-derivation} (@pxref{Defining Packages}).
  8539. @end deffn
  8540. @node G-Expressions
  8541. @section G-Expressions
  8542. @cindex G-expression
  8543. @cindex build code quoting
  8544. So we have ``derivations'', which represent a sequence of build actions
  8545. to be performed to produce an item in the store (@pxref{Derivations}).
  8546. These build actions are performed when asking the daemon to actually
  8547. build the derivations; they are run by the daemon in a container
  8548. (@pxref{Invoking guix-daemon}).
  8549. @cindex code staging
  8550. @cindex staging, of code
  8551. @cindex strata of code
  8552. It should come as no surprise that we like to write these build actions
  8553. in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
  8554. code@footnote{The term @dfn{stratum} in this context was coined by
  8555. Manuel Serrano et al.@: in the context of their work on Hop. Oleg
  8556. Kiselyov, who has written insightful
  8557. @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
  8558. on this topic}, refers to this kind of code generation as
  8559. @dfn{staging}.}: the ``host code''---code that defines packages, talks
  8560. to the daemon, etc.---and the ``build code''---code that actually
  8561. performs build actions, such as making directories, invoking
  8562. @command{make}, and so on (@pxref{Build Phases}).
  8563. To describe a derivation and its build actions, one typically needs to
  8564. embed build code inside host code. It boils down to manipulating build
  8565. code as data, and the homoiconicity of Scheme---code has a direct
  8566. representation as data---comes in handy for that. But we need more than
  8567. the normal @code{quasiquote} mechanism in Scheme to construct build
  8568. expressions.
  8569. The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
  8570. S-expressions adapted to build expressions. G-expressions, or
  8571. @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
  8572. @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
  8573. @code{#$}, and @code{#$@@}), which are comparable to
  8574. @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
  8575. respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
  8576. GNU Guile Reference Manual}). However, there are major differences:
  8577. @itemize
  8578. @item
  8579. Gexps are meant to be written to a file and run or manipulated by other
  8580. processes.
  8581. @item
  8582. When a high-level object such as a package or derivation is unquoted
  8583. inside a gexp, the result is as if its output file name had been
  8584. introduced.
  8585. @item
  8586. Gexps carry information about the packages or derivations they refer to,
  8587. and these dependencies are automatically added as inputs to the build
  8588. processes that use them.
  8589. @end itemize
  8590. @cindex lowering, of high-level objects in gexps
  8591. This mechanism is not limited to package and derivation
  8592. objects: @dfn{compilers} able to ``lower'' other high-level objects to
  8593. derivations or files in the store can be defined,
  8594. such that these objects can also be inserted
  8595. into gexps. For example, a useful type of high-level objects that can be
  8596. inserted in a gexp is ``file-like objects'', which make it easy to
  8597. add files to the store and to refer to them in
  8598. derivations and such (see @code{local-file} and @code{plain-file}
  8599. below).
  8600. To illustrate the idea, here is an example of a gexp:
  8601. @lisp
  8602. (define build-exp
  8603. #~(begin
  8604. (mkdir #$output)
  8605. (chdir #$output)
  8606. (symlink (string-append #$coreutils "/bin/ls")
  8607. "list-files")))
  8608. @end lisp
  8609. This gexp can be passed to @code{gexp->derivation}; we obtain a
  8610. derivation that builds a directory containing exactly one symlink to
  8611. @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
  8612. @lisp
  8613. (gexp->derivation "the-thing" build-exp)
  8614. @end lisp
  8615. As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
  8616. substituted to the reference to the @var{coreutils} package in the
  8617. actual build code, and @var{coreutils} is automatically made an input to
  8618. the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
  8619. output)}) is replaced by a string containing the directory name of the
  8620. output of the derivation.
  8621. @cindex cross compilation
  8622. In a cross-compilation context, it is useful to distinguish between
  8623. references to the @emph{native} build of a package---that can run on the
  8624. host---versus references to cross builds of a package. To that end, the
  8625. @code{#+} plays the same role as @code{#$}, but is a reference to a
  8626. native package build:
  8627. @lisp
  8628. (gexp->derivation "vi"
  8629. #~(begin
  8630. (mkdir #$output)
  8631. (mkdir (string-append #$output "/bin"))
  8632. (system* (string-append #+coreutils "/bin/ln")
  8633. "-s"
  8634. (string-append #$emacs "/bin/emacs")
  8635. (string-append #$output "/bin/vi")))
  8636. #:target "aarch64-linux-gnu")
  8637. @end lisp
  8638. @noindent
  8639. In the example above, the native build of @var{coreutils} is used, so
  8640. that @command{ln} can actually run on the host; but then the
  8641. cross-compiled build of @var{emacs} is referenced.
  8642. @cindex imported modules, for gexps
  8643. @findex with-imported-modules
  8644. Another gexp feature is @dfn{imported modules}: sometimes you want to be
  8645. able to use certain Guile modules from the ``host environment'' in the
  8646. gexp, so those modules should be imported in the ``build environment''.
  8647. The @code{with-imported-modules} form allows you to express that:
  8648. @lisp
  8649. (let ((build (with-imported-modules '((guix build utils))
  8650. #~(begin
  8651. (use-modules (guix build utils))
  8652. (mkdir-p (string-append #$output "/bin"))))))
  8653. (gexp->derivation "empty-dir"
  8654. #~(begin
  8655. #$build
  8656. (display "success!\n")
  8657. #t)))
  8658. @end lisp
  8659. @noindent
  8660. In this example, the @code{(guix build utils)} module is automatically
  8661. pulled into the isolated build environment of our gexp, such that
  8662. @code{(use-modules (guix build utils))} works as expected.
  8663. @cindex module closure
  8664. @findex source-module-closure
  8665. Usually you want the @emph{closure} of the module to be imported---i.e.,
  8666. the module itself and all the modules it depends on---rather than just
  8667. the module; failing to do that, attempts to use the module will fail
  8668. because of missing dependent modules. The @code{source-module-closure}
  8669. procedure computes the closure of a module by looking at its source file
  8670. headers, which comes in handy in this case:
  8671. @lisp
  8672. (use-modules (guix modules)) ;for 'source-module-closure'
  8673. (with-imported-modules (source-module-closure
  8674. '((guix build utils)
  8675. (gnu build image)))
  8676. (gexp->derivation "something-with-vms"
  8677. #~(begin
  8678. (use-modules (guix build utils)
  8679. (gnu build image))
  8680. @dots{})))
  8681. @end lisp
  8682. @cindex extensions, for gexps
  8683. @findex with-extensions
  8684. In the same vein, sometimes you want to import not just pure-Scheme
  8685. modules, but also ``extensions'' such as Guile bindings to C libraries
  8686. or other ``full-blown'' packages. Say you need the @code{guile-json}
  8687. package available on the build side, here's how you would do it:
  8688. @lisp
  8689. (use-modules (gnu packages guile)) ;for 'guile-json'
  8690. (with-extensions (list guile-json)
  8691. (gexp->derivation "something-with-json"
  8692. #~(begin
  8693. (use-modules (json))
  8694. @dots{})))
  8695. @end lisp
  8696. The syntactic form to construct gexps is summarized below.
  8697. @deffn {Scheme Syntax} #~@var{exp}
  8698. @deffnx {Scheme Syntax} (gexp @var{exp})
  8699. Return a G-expression containing @var{exp}. @var{exp} may contain one
  8700. or more of the following forms:
  8701. @table @code
  8702. @item #$@var{obj}
  8703. @itemx (ungexp @var{obj})
  8704. Introduce a reference to @var{obj}. @var{obj} may have one of the
  8705. supported types, for example a package or a
  8706. derivation, in which case the @code{ungexp} form is replaced by its
  8707. output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
  8708. If @var{obj} is a list, it is traversed and references to supported
  8709. objects are substituted similarly.
  8710. If @var{obj} is another gexp, its contents are inserted and its
  8711. dependencies are added to those of the containing gexp.
  8712. If @var{obj} is another kind of object, it is inserted as is.
  8713. @item #$@var{obj}:@var{output}
  8714. @itemx (ungexp @var{obj} @var{output})
  8715. This is like the form above, but referring explicitly to the
  8716. @var{output} of @var{obj}---this is useful when @var{obj} produces
  8717. multiple outputs (@pxref{Packages with Multiple Outputs}).
  8718. @item #+@var{obj}
  8719. @itemx #+@var{obj}:output
  8720. @itemx (ungexp-native @var{obj})
  8721. @itemx (ungexp-native @var{obj} @var{output})
  8722. Same as @code{ungexp}, but produces a reference to the @emph{native}
  8723. build of @var{obj} when used in a cross compilation context.
  8724. @item #$output[:@var{output}]
  8725. @itemx (ungexp output [@var{output}])
  8726. Insert a reference to derivation output @var{output}, or to the main
  8727. output when @var{output} is omitted.
  8728. This only makes sense for gexps passed to @code{gexp->derivation}.
  8729. @item #$@@@var{lst}
  8730. @itemx (ungexp-splicing @var{lst})
  8731. Like the above, but splices the contents of @var{lst} inside the
  8732. containing list.
  8733. @item #+@@@var{lst}
  8734. @itemx (ungexp-native-splicing @var{lst})
  8735. Like the above, but refers to native builds of the objects listed in
  8736. @var{lst}.
  8737. @end table
  8738. G-expressions created by @code{gexp} or @code{#~} are run-time objects
  8739. of the @code{gexp?} type (see below).
  8740. @end deffn
  8741. @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
  8742. Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
  8743. in their execution environment.
  8744. Each item in @var{modules} can be the name of a module, such as
  8745. @code{(guix build utils)}, or it can be a module name, followed by an
  8746. arrow, followed by a file-like object:
  8747. @lisp
  8748. `((guix build utils)
  8749. (guix gcrypt)
  8750. ((guix config) => ,(scheme-file "config.scm"
  8751. #~(define-module @dots{}))))
  8752. @end lisp
  8753. @noindent
  8754. In the example above, the first two modules are taken from the search
  8755. path, and the last one is created from the given file-like object.
  8756. This form has @emph{lexical} scope: it has an effect on the gexps
  8757. directly defined in @var{body}@dots{}, but not on those defined, say, in
  8758. procedures called from @var{body}@dots{}.
  8759. @end deffn
  8760. @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
  8761. Mark the gexps defined in @var{body}@dots{} as requiring
  8762. @var{extensions} in their build and execution environment.
  8763. @var{extensions} is typically a list of package objects such as those
  8764. defined in the @code{(gnu packages guile)} module.
  8765. Concretely, the packages listed in @var{extensions} are added to the
  8766. load path while compiling imported modules in @var{body}@dots{}; they
  8767. are also added to the load path of the gexp returned by
  8768. @var{body}@dots{}.
  8769. @end deffn
  8770. @deffn {Scheme Procedure} gexp? @var{obj}
  8771. Return @code{#t} if @var{obj} is a G-expression.
  8772. @end deffn
  8773. G-expressions are meant to be written to disk, either as code building
  8774. some derivation, or as plain files in the store. The monadic procedures
  8775. below allow you to do that (@pxref{The Store Monad}, for more
  8776. information about monads).
  8777. @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
  8778. [#:system (%current-system)] [#:target #f] [#:graft? #t] @
  8779. [#:hash #f] [#:hash-algo #f] @
  8780. [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
  8781. [#:module-path @code{%load-path}] @
  8782. [#:effective-version "2.2"] @
  8783. [#:references-graphs #f] [#:allowed-references #f] @
  8784. [#:disallowed-references #f] @
  8785. [#:leaked-env-vars #f] @
  8786. [#:script-name (string-append @var{name} "-builder")] @
  8787. [#:deprecation-warnings #f] @
  8788. [#:local-build? #f] [#:substitutable? #t] @
  8789. [#:properties '()] [#:guile-for-build #f]
  8790. Return a derivation @var{name} that runs @var{exp} (a gexp) with
  8791. @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
  8792. stored in a file called @var{script-name}. When @var{target} is true,
  8793. it is used as the cross-compilation target triplet for packages referred
  8794. to by @var{exp}.
  8795. @var{modules} is deprecated in favor of @code{with-imported-modules}.
  8796. Its meaning is to
  8797. make @var{modules} available in the evaluation context of @var{exp};
  8798. @var{modules} is a list of names of Guile modules searched in
  8799. @var{module-path} to be copied in the store, compiled, and made available in
  8800. the load path during the execution of @var{exp}---e.g., @code{((guix
  8801. build utils) (guix build gnu-build-system))}.
  8802. @var{effective-version} determines the string to use when adding extensions of
  8803. @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
  8804. @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
  8805. applicable.
  8806. When @var{references-graphs} is true, it must be a list of tuples of one of the
  8807. following forms:
  8808. @example
  8809. (@var{file-name} @var{package})
  8810. (@var{file-name} @var{package} @var{output})
  8811. (@var{file-name} @var{derivation})
  8812. (@var{file-name} @var{derivation} @var{output})
  8813. (@var{file-name} @var{store-item})
  8814. @end example
  8815. The right-hand-side of each element of @var{references-graphs} is automatically made
  8816. an input of the build process of @var{exp}. In the build environment, each
  8817. @var{file-name} contains the reference graph of the corresponding item, in a simple
  8818. text format.
  8819. @var{allowed-references} must be either @code{#f} or a list of output names and packages.
  8820. In the latter case, the list denotes store items that the result is allowed to
  8821. refer to. Any reference to another store item will lead to a build error.
  8822. Similarly for @var{disallowed-references}, which can list items that must not be
  8823. referenced by the outputs.
  8824. @var{deprecation-warnings} determines whether to show deprecation warnings while
  8825. compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
  8826. The other arguments are as for @code{derivation} (@pxref{Derivations}).
  8827. @end deffn
  8828. @cindex file-like objects
  8829. The @code{local-file}, @code{plain-file}, @code{computed-file},
  8830. @code{program-file}, and @code{scheme-file} procedures below return
  8831. @dfn{file-like objects}. That is, when unquoted in a G-expression,
  8832. these objects lead to a file in the store. Consider this G-expression:
  8833. @lisp
  8834. #~(system* #$(file-append glibc "/sbin/nscd") "-f"
  8835. #$(local-file "/tmp/my-nscd.conf"))
  8836. @end lisp
  8837. The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
  8838. to the store. Once expanded, for instance @i{via}
  8839. @code{gexp->derivation}, the G-expression refers to that copy under
  8840. @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
  8841. does not have any effect on what the G-expression does.
  8842. @code{plain-file} can be used similarly; it differs in that the file
  8843. content is directly passed as a string.
  8844. @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
  8845. [#:recursive? #f] [#:select? (const #t)]
  8846. Return an object representing local file @var{file} to add to the store;
  8847. this object can be used in a gexp. If @var{file} is a literal string
  8848. denoting a relative file name, it is looked up relative to the source
  8849. file where it appears; if @var{file} is not a literal string, it is
  8850. looked up relative to the current working directory at run time.
  8851. @var{file} will be added to the store under @var{name}--by default the
  8852. base name of @var{file}.
  8853. When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
  8854. designates a flat file and @var{recursive?} is true, its contents are added, and its
  8855. permission bits are kept.
  8856. When @var{recursive?} is true, call @code{(@var{select?} @var{file}
  8857. @var{stat})} for each directory entry, where @var{file} is the entry's
  8858. absolute file name and @var{stat} is the result of @code{lstat}; exclude
  8859. entries for which @var{select?} does not return true.
  8860. This is the declarative counterpart of the @code{interned-file} monadic
  8861. procedure (@pxref{The Store Monad, @code{interned-file}}).
  8862. @end deffn
  8863. @deffn {Scheme Procedure} plain-file @var{name} @var{content}
  8864. Return an object representing a text file called @var{name} with the given
  8865. @var{content} (a string or a bytevector) to be added to the store.
  8866. This is the declarative counterpart of @code{text-file}.
  8867. @end deffn
  8868. @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
  8869. [#:local-build? #t]
  8870. [#:options '()]
  8871. Return an object representing the store item @var{name}, a file or
  8872. directory computed by @var{gexp}. When @var{local-build?} is true (the
  8873. default), the derivation is built locally. @var{options} is a list of
  8874. additional arguments to pass to @code{gexp->derivation}.
  8875. This is the declarative counterpart of @code{gexp->derivation}.
  8876. @end deffn
  8877. @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
  8878. [#:guile (default-guile)] [#:module-path %load-path] @
  8879. [#:system (%current-system)] [#:target #f]
  8880. Return an executable script @var{name} that runs @var{exp} using
  8881. @var{guile}, with @var{exp}'s imported modules in its search path.
  8882. Look up @var{exp}'s modules in @var{module-path}.
  8883. The example below builds a script that simply invokes the @command{ls}
  8884. command:
  8885. @lisp
  8886. (use-modules (guix gexp) (gnu packages base))
  8887. (gexp->script "list-files"
  8888. #~(execl #$(file-append coreutils "/bin/ls")
  8889. "ls"))
  8890. @end lisp
  8891. When ``running'' it through the store (@pxref{The Store Monad,
  8892. @code{run-with-store}}), we obtain a derivation that produces an
  8893. executable file @file{/gnu/store/@dots{}-list-files} along these lines:
  8894. @example
  8895. #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
  8896. !#
  8897. (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
  8898. @end example
  8899. @end deffn
  8900. @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
  8901. [#:guile #f] [#:module-path %load-path]
  8902. Return an object representing the executable store item @var{name} that
  8903. runs @var{gexp}. @var{guile} is the Guile package used to execute that
  8904. script. Imported modules of @var{gexp} are looked up in @var{module-path}.
  8905. This is the declarative counterpart of @code{gexp->script}.
  8906. @end deffn
  8907. @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
  8908. [#:set-load-path? #t] [#:module-path %load-path] @
  8909. [#:splice? #f] @
  8910. [#:guile (default-guile)]
  8911. Return a derivation that builds a file @var{name} containing @var{exp}.
  8912. When @var{splice?} is true, @var{exp} is considered to be a list of
  8913. expressions that will be spliced in the resulting file.
  8914. When @var{set-load-path?} is true, emit code in the resulting file to
  8915. set @code{%load-path} and @code{%load-compiled-path} to honor
  8916. @var{exp}'s imported modules. Look up @var{exp}'s modules in
  8917. @var{module-path}.
  8918. The resulting file holds references to all the dependencies of @var{exp}
  8919. or a subset thereof.
  8920. @end deffn
  8921. @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} @
  8922. [#:splice? #f] [#:set-load-path? #t]
  8923. Return an object representing the Scheme file @var{name} that contains
  8924. @var{exp}.
  8925. This is the declarative counterpart of @code{gexp->file}.
  8926. @end deffn
  8927. @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
  8928. Return as a monadic value a derivation that builds a text file
  8929. containing all of @var{text}. @var{text} may list, in addition to
  8930. strings, objects of any type that can be used in a gexp: packages,
  8931. derivations, local file objects, etc. The resulting store file holds
  8932. references to all these.
  8933. This variant should be preferred over @code{text-file} anytime the file
  8934. to create will reference items from the store. This is typically the
  8935. case when building a configuration file that embeds store file names,
  8936. like this:
  8937. @lisp
  8938. (define (profile.sh)
  8939. ;; Return the name of a shell script in the store that
  8940. ;; initializes the 'PATH' environment variable.
  8941. (text-file* "profile.sh"
  8942. "export PATH=" coreutils "/bin:"
  8943. grep "/bin:" sed "/bin\n"))
  8944. @end lisp
  8945. In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
  8946. will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
  8947. preventing them from being garbage-collected during its lifetime.
  8948. @end deffn
  8949. @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
  8950. Return an object representing store file @var{name} containing
  8951. @var{text}. @var{text} is a sequence of strings and file-like objects,
  8952. as in:
  8953. @lisp
  8954. (mixed-text-file "profile"
  8955. "export PATH=" coreutils "/bin:" grep "/bin")
  8956. @end lisp
  8957. This is the declarative counterpart of @code{text-file*}.
  8958. @end deffn
  8959. @deffn {Scheme Procedure} file-union @var{name} @var{files}
  8960. Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
  8961. Each item in @var{files} must be a two-element list where the first element is the
  8962. file name to use in the new directory, and the second element is a gexp
  8963. denoting the target file. Here's an example:
  8964. @lisp
  8965. (file-union "etc"
  8966. `(("hosts" ,(plain-file "hosts"
  8967. "127.0.0.1 localhost"))
  8968. ("bashrc" ,(plain-file "bashrc"
  8969. "alias ls='ls --color=auto'"))))
  8970. @end lisp
  8971. This yields an @code{etc} directory containing these two files.
  8972. @end deffn
  8973. @deffn {Scheme Procedure} directory-union @var{name} @var{things}
  8974. Return a directory that is the union of @var{things}, where @var{things} is a list of
  8975. file-like objects denoting directories. For example:
  8976. @lisp
  8977. (directory-union "guile+emacs" (list guile emacs))
  8978. @end lisp
  8979. yields a directory that is the union of the @code{guile} and @code{emacs} packages.
  8980. @end deffn
  8981. @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
  8982. Return a file-like object that expands to the concatenation of @var{obj}
  8983. and @var{suffix}, where @var{obj} is a lowerable object and each
  8984. @var{suffix} is a string.
  8985. As an example, consider this gexp:
  8986. @lisp
  8987. (gexp->script "run-uname"
  8988. #~(system* #$(file-append coreutils
  8989. "/bin/uname")))
  8990. @end lisp
  8991. The same effect could be achieved with:
  8992. @lisp
  8993. (gexp->script "run-uname"
  8994. #~(system* (string-append #$coreutils
  8995. "/bin/uname")))
  8996. @end lisp
  8997. There is one difference though: in the @code{file-append} case, the
  8998. resulting script contains the absolute file name as a string, whereas in
  8999. the second case, the resulting script contains a @code{(string-append
  9000. @dots{})} expression to construct the file name @emph{at run time}.
  9001. @end deffn
  9002. @deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{}
  9003. @deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{}
  9004. Bind @var{system} to the currently targeted system---e.g.,
  9005. @code{"x86_64-linux"}---within @var{body}.
  9006. In the second case, additionally bind @var{target} to the current
  9007. cross-compilation target---a GNU triplet such as
  9008. @code{"arm-linux-gnueabihf"}---or @code{#f} if we are not
  9009. cross-compiling.
  9010. @code{let-system} is useful in the occasional case where the object
  9011. spliced into the gexp depends on the target system, as in this example:
  9012. @lisp
  9013. #~(system*
  9014. #+(let-system system
  9015. (cond ((string-prefix? "armhf-" system)
  9016. (file-append qemu "/bin/qemu-system-arm"))
  9017. ((string-prefix? "x86_64-" system)
  9018. (file-append qemu "/bin/qemu-system-x86_64"))
  9019. (else
  9020. (error "dunno!"))))
  9021. "-net" "user" #$image)
  9022. @end lisp
  9023. @end deffn
  9024. @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
  9025. This macro is similar to the @code{parameterize} form for
  9026. dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
  9027. Guile Reference Manual}). The key difference is that it takes effect
  9028. when the file-like object returned by @var{exp} is lowered to a
  9029. derivation or store item.
  9030. A typical use of @code{with-parameters} is to force the system in effect
  9031. for a given object:
  9032. @lisp
  9033. (with-parameters ((%current-system "i686-linux"))
  9034. coreutils)
  9035. @end lisp
  9036. The example above returns an object that corresponds to the i686 build
  9037. of Coreutils, regardless of the current value of @code{%current-system}.
  9038. @end deffn
  9039. Of course, in addition to gexps embedded in ``host'' code, there are
  9040. also modules containing build tools. To make it clear that they are
  9041. meant to be used in the build stratum, these modules are kept in the
  9042. @code{(guix build @dots{})} name space.
  9043. @cindex lowering, of high-level objects in gexps
  9044. Internally, high-level objects are @dfn{lowered}, using their compiler,
  9045. to either derivations or store items. For instance, lowering a package
  9046. yields a derivation, and lowering a @code{plain-file} yields a store
  9047. item. This is achieved using the @code{lower-object} monadic procedure.
  9048. @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
  9049. [#:target #f]
  9050. Return as a value in @code{%store-monad} the derivation or store item
  9051. corresponding to @var{obj} for @var{system}, cross-compiling for
  9052. @var{target} if @var{target} is true. @var{obj} must be an object that
  9053. has an associated gexp compiler, such as a @code{<package>}.
  9054. @end deffn
  9055. @deffn {Procedure} gexp->approximate-sexp @var{gexp}
  9056. Sometimes, it may be useful to convert a G-exp into a S-exp. For
  9057. example, some linters (@pxref{Invoking guix lint}) peek into the build
  9058. phases of a package to detect potential problems. This conversion can
  9059. be achieved with this procedure. However, some information can be lost
  9060. in the process. More specifically, lowerable objects will be silently
  9061. replaced with some arbitrary object -- currently the list
  9062. @code{(*approximate*)}, but this may change.
  9063. @end deffn
  9064. @node Invoking guix repl
  9065. @section Invoking @command{guix repl}
  9066. @cindex REPL, read-eval-print loop, script
  9067. The @command{guix repl} command makes it easier to program Guix in Guile
  9068. by launching a Guile @dfn{read-eval-print loop} (REPL) for interactive
  9069. programming (@pxref{Using Guile Interactively,,, guile,
  9070. GNU Guile Reference Manual}), or by running Guile scripts
  9071. (@pxref{Running Guile Scripts,,, guile,
  9072. GNU Guile Reference Manual}).
  9073. Compared to just launching the @command{guile}
  9074. command, @command{guix repl} guarantees that all the Guix modules and all its
  9075. dependencies are available in the search path.
  9076. The general syntax is:
  9077. @example
  9078. guix repl @var{options} [@var{file} @var{args}]
  9079. @end example
  9080. When a @var{file} argument is provided, @var{file} is
  9081. executed as a Guile scripts:
  9082. @example
  9083. guix repl my-script.scm
  9084. @end example
  9085. To pass arguments to the script, use @code{--} to prevent them from
  9086. being interpreted as arguments to @command{guix repl} itself:
  9087. @example
  9088. guix repl -- my-script.scm --input=foo.txt
  9089. @end example
  9090. To make a script executable directly from the shell, using the guix
  9091. executable that is on the user's search path, add the following two
  9092. lines at the top of the script:
  9093. @example
  9094. @code{#!/usr/bin/env -S guix repl --}
  9095. @code{!#}
  9096. @end example
  9097. Without a file name argument, a Guile REPL is started:
  9098. @example
  9099. $ guix repl
  9100. scheme@@(guile-user)> ,use (gnu packages base)
  9101. scheme@@(guile-user)> coreutils
  9102. $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
  9103. @end example
  9104. @cindex inferiors
  9105. In addition, @command{guix repl} implements a simple machine-readable REPL
  9106. protocol for use by @code{(guix inferior)}, a facility to interact with
  9107. @dfn{inferiors}, separate processes running a potentially different revision
  9108. of Guix.
  9109. The available options are as follows:
  9110. @table @code
  9111. @item --type=@var{type}
  9112. @itemx -t @var{type}
  9113. Start a REPL of the given @var{TYPE}, which can be one of the following:
  9114. @table @code
  9115. @item guile
  9116. This is default, and it spawns a standard full-featured Guile REPL.
  9117. @item machine
  9118. Spawn a REPL that uses the machine-readable protocol. This is the protocol
  9119. that the @code{(guix inferior)} module speaks.
  9120. @end table
  9121. @item --listen=@var{endpoint}
  9122. By default, @command{guix repl} reads from standard input and writes to
  9123. standard output. When this option is passed, it will instead listen for
  9124. connections on @var{endpoint}. Here are examples of valid options:
  9125. @table @code
  9126. @item --listen=tcp:37146
  9127. Accept connections on localhost on port 37146.
  9128. @item --listen=unix:/tmp/socket
  9129. Accept connections on the Unix-domain socket @file{/tmp/socket}.
  9130. @end table
  9131. @item --load-path=@var{directory}
  9132. @itemx -L @var{directory}
  9133. Add @var{directory} to the front of the package module search path
  9134. (@pxref{Package Modules}).
  9135. This allows users to define their own packages and make them visible to
  9136. the script or REPL.
  9137. @item -q
  9138. Inhibit loading of the @file{~/.guile} file. By default, that
  9139. configuration file is loaded when spawning a @code{guile} REPL.
  9140. @end table
  9141. @c *********************************************************************
  9142. @node Utilities
  9143. @chapter Utilities
  9144. This section describes Guix command-line utilities. Some of them are
  9145. primarily targeted at developers and users who write new package
  9146. definitions, while others are more generally useful. They complement
  9147. the Scheme programming interface of Guix in a convenient way.
  9148. @menu
  9149. * Invoking guix build:: Building packages from the command line.
  9150. * Invoking guix edit:: Editing package definitions.
  9151. * Invoking guix download:: Downloading a file and printing its hash.
  9152. * Invoking guix hash:: Computing the cryptographic hash of a file.
  9153. * Invoking guix import:: Importing package definitions.
  9154. * Invoking guix refresh:: Updating package definitions.
  9155. * Invoking guix style:: Styling package definitions.
  9156. * Invoking guix lint:: Finding errors in package definitions.
  9157. * Invoking guix size:: Profiling disk usage.
  9158. * Invoking guix graph:: Visualizing the graph of packages.
  9159. * Invoking guix publish:: Sharing substitutes.
  9160. * Invoking guix challenge:: Challenging substitute servers.
  9161. * Invoking guix copy:: Copying to and from a remote store.
  9162. * Invoking guix container:: Process isolation.
  9163. * Invoking guix weather:: Assessing substitute availability.
  9164. * Invoking guix processes:: Listing client processes.
  9165. @end menu
  9166. @node Invoking guix build
  9167. @section Invoking @command{guix build}
  9168. @cindex package building
  9169. @cindex @command{guix build}
  9170. The @command{guix build} command builds packages or derivations and
  9171. their dependencies, and prints the resulting store paths. Note that it
  9172. does not modify the user's profile---this is the job of the
  9173. @command{guix package} command (@pxref{Invoking guix package}). Thus,
  9174. it is mainly useful for distribution developers.
  9175. The general syntax is:
  9176. @example
  9177. guix build @var{options} @var{package-or-derivation}@dots{}
  9178. @end example
  9179. As an example, the following command builds the latest versions of Emacs
  9180. and of Guile, displays their build logs, and finally displays the
  9181. resulting directories:
  9182. @example
  9183. guix build emacs guile
  9184. @end example
  9185. Similarly, the following command builds all the available packages:
  9186. @example
  9187. guix build --quiet --keep-going \
  9188. $(guix package -A | awk '@{ print $1 "@@" $2 @}')
  9189. @end example
  9190. @var{package-or-derivation} may be either the name of a package found in
  9191. the software distribution such as @code{coreutils} or
  9192. @code{coreutils@@8.20}, or a derivation such as
  9193. @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
  9194. package with the corresponding name (and optionally version) is searched
  9195. for among the GNU distribution modules (@pxref{Package Modules}).
  9196. Alternatively, the @option{--expression} option may be used to specify a
  9197. Scheme expression that evaluates to a package; this is useful when
  9198. disambiguating among several same-named packages or package variants is
  9199. needed.
  9200. There may be zero or more @var{options}. The available options are
  9201. described in the subsections below.
  9202. @menu
  9203. * Common Build Options:: Build options for most commands.
  9204. * Package Transformation Options:: Creating variants of packages.
  9205. * Additional Build Options:: Options specific to 'guix build'.
  9206. * Debugging Build Failures:: Real life packaging experience.
  9207. @end menu
  9208. @node Common Build Options
  9209. @subsection Common Build Options
  9210. A number of options that control the build process are common to
  9211. @command{guix build} and other commands that can spawn builds, such as
  9212. @command{guix package} or @command{guix archive}. These are the
  9213. following:
  9214. @table @code
  9215. @item --load-path=@var{directory}
  9216. @itemx -L @var{directory}
  9217. Add @var{directory} to the front of the package module search path
  9218. (@pxref{Package Modules}).
  9219. This allows users to define their own packages and make them visible to
  9220. the command-line tools.
  9221. @item --keep-failed
  9222. @itemx -K
  9223. Keep the build tree of failed builds. Thus, if a build fails, its build
  9224. tree is kept under @file{/tmp}, in a directory whose name is shown at
  9225. the end of the build log. This is useful when debugging build issues.
  9226. @xref{Debugging Build Failures}, for tips and tricks on how to debug
  9227. build issues.
  9228. This option implies @option{--no-offload}, and it has no effect when
  9229. connecting to a remote daemon with a @code{guix://} URI (@pxref{The
  9230. Store, the @env{GUIX_DAEMON_SOCKET} variable}).
  9231. @item --keep-going
  9232. @itemx -k
  9233. Keep going when some of the derivations fail to build; return only once
  9234. all the builds have either completed or failed.
  9235. The default behavior is to stop as soon as one of the specified
  9236. derivations has failed.
  9237. @item --dry-run
  9238. @itemx -n
  9239. Do not build the derivations.
  9240. @anchor{fallback-option}
  9241. @item --fallback
  9242. When substituting a pre-built binary fails, fall back to building
  9243. packages locally (@pxref{Substitution Failure}).
  9244. @item --substitute-urls=@var{urls}
  9245. @anchor{client-substitute-urls}
  9246. Consider @var{urls} the whitespace-separated list of substitute source
  9247. URLs, overriding the default list of URLs of @command{guix-daemon}
  9248. (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
  9249. This means that substitutes may be downloaded from @var{urls}, provided
  9250. they are signed by a key authorized by the system administrator
  9251. (@pxref{Substitutes}).
  9252. When @var{urls} is the empty string, substitutes are effectively
  9253. disabled.
  9254. @item --no-substitutes
  9255. Do not use substitutes for build products. That is, always build things
  9256. locally instead of allowing downloads of pre-built binaries
  9257. (@pxref{Substitutes}).
  9258. @item --no-grafts
  9259. Do not ``graft'' packages. In practice, this means that package updates
  9260. available as grafts are not applied. @xref{Security Updates}, for more
  9261. information on grafts.
  9262. @item --rounds=@var{n}
  9263. Build each derivation @var{n} times in a row, and raise an error if
  9264. consecutive build results are not bit-for-bit identical.
  9265. This is a useful way to detect non-deterministic builds processes.
  9266. Non-deterministic build processes are a problem because they make it
  9267. practically impossible for users to @emph{verify} whether third-party
  9268. binaries are genuine. @xref{Invoking guix challenge}, for more.
  9269. When used in conjunction with @option{--keep-failed}, the differing
  9270. output is kept in the store, under @file{/gnu/store/@dots{}-check}.
  9271. This makes it easy to look for differences between the two results.
  9272. @item --no-offload
  9273. Do not use offload builds to other machines (@pxref{Daemon Offload
  9274. Setup}). That is, always build things locally instead of offloading
  9275. builds to remote machines.
  9276. @item --max-silent-time=@var{seconds}
  9277. When the build or substitution process remains silent for more than
  9278. @var{seconds}, terminate it and report a build failure.
  9279. By default, the daemon's setting is honored (@pxref{Invoking
  9280. guix-daemon, @option{--max-silent-time}}).
  9281. @item --timeout=@var{seconds}
  9282. Likewise, when the build or substitution process lasts for more than
  9283. @var{seconds}, terminate it and report a build failure.
  9284. By default, the daemon's setting is honored (@pxref{Invoking
  9285. guix-daemon, @option{--timeout}}).
  9286. @c Note: This option is actually not part of %standard-build-options but
  9287. @c most programs honor it.
  9288. @cindex verbosity, of the command-line tools
  9289. @cindex build logs, verbosity
  9290. @item -v @var{level}
  9291. @itemx --verbosity=@var{level}
  9292. Use the given verbosity @var{level}, an integer. Choosing 0 means that
  9293. no output is produced, 1 is for quiet output; 2 is similar to 1 but it
  9294. additionally displays download URLs; 3 shows all the build log output on
  9295. standard error.
  9296. @item --cores=@var{n}
  9297. @itemx -c @var{n}
  9298. Allow the use of up to @var{n} CPU cores for the build. The special
  9299. value @code{0} means to use as many CPU cores as available.
  9300. @item --max-jobs=@var{n}
  9301. @itemx -M @var{n}
  9302. Allow at most @var{n} build jobs in parallel. @xref{Invoking
  9303. guix-daemon, @option{--max-jobs}}, for details about this option and the
  9304. equivalent @command{guix-daemon} option.
  9305. @item --debug=@var{level}
  9306. Produce debugging output coming from the build daemon. @var{level} must be an
  9307. integer between 0 and 5; higher means more verbose output. Setting a level of
  9308. 4 or more may be helpful when debugging setup issues with the build daemon.
  9309. @end table
  9310. Behind the scenes, @command{guix build} is essentially an interface to
  9311. the @code{package-derivation} procedure of the @code{(guix packages)}
  9312. module, and to the @code{build-derivations} procedure of the @code{(guix
  9313. derivations)} module.
  9314. In addition to options explicitly passed on the command line,
  9315. @command{guix build} and other @command{guix} commands that support
  9316. building honor the @env{GUIX_BUILD_OPTIONS} environment variable.
  9317. @defvr {Environment Variable} GUIX_BUILD_OPTIONS
  9318. Users can define this variable to a list of command line options that
  9319. will automatically be used by @command{guix build} and other
  9320. @command{guix} commands that can perform builds, as in the example
  9321. below:
  9322. @example
  9323. $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
  9324. @end example
  9325. These options are parsed independently, and the result is appended to
  9326. the parsed command-line options.
  9327. @end defvr
  9328. @node Package Transformation Options
  9329. @subsection Package Transformation Options
  9330. @cindex package variants
  9331. Another set of command-line options supported by @command{guix build}
  9332. and also @command{guix package} are @dfn{package transformation
  9333. options}. These are options that make it possible to define @dfn{package
  9334. variants}---for instance, packages built from different source code.
  9335. This is a convenient way to create customized packages on the fly
  9336. without having to type in the definitions of package variants
  9337. (@pxref{Defining Packages}).
  9338. Package transformation options are preserved across upgrades:
  9339. @command{guix upgrade} attempts to apply transformation options
  9340. initially used when creating the profile to the upgraded packages.
  9341. The available options are listed below. Most commands support them and
  9342. also support a @option{--help-transform} option that lists all the
  9343. available options and a synopsis (these options are not shown in the
  9344. @option{--help} output for brevity).
  9345. @table @code
  9346. @cindex performance, tuning code
  9347. @cindex optimization, of package code
  9348. @cindex tuning, of package code
  9349. @cindex SIMD support
  9350. @cindex tunable packages
  9351. @cindex package multi-versioning
  9352. @item --tune[=@var{cpu}]
  9353. Use versions of the packages marked as ``tunable'' optimized for
  9354. @var{cpu}. When @var{cpu} is @code{native}, or when it is omitted, tune
  9355. for the CPU on which the @command{guix} command is running.
  9356. Valid @var{cpu} names are those recognized by the underlying compiler,
  9357. by default the GNU Compiler Collection. On x86_64 processors, this
  9358. includes CPU names such as @code{nehalem}, @code{haswell}, and
  9359. @code{skylake} (@pxref{x86 Options, @code{-march},, gcc, Using the GNU
  9360. Compiler Collection (GCC)}).
  9361. As new generations of CPUs come out, they augment the standard
  9362. instruction set architecture (ISA) with additional instructions, in
  9363. particular instructions for single-instruction/multiple-data (SIMD)
  9364. parallel processing. For example, while Core2 and Skylake CPUs both
  9365. implement the x86_64 ISA, only the latter supports AVX2 SIMD
  9366. instructions.
  9367. The primary gain one can expect from @option{--tune} is for programs
  9368. that can make use of those SIMD capabilities @emph{and} that do not
  9369. already have a mechanism to select the right optimized code at run time.
  9370. Packages that have the @code{tunable?} property set are considered
  9371. @dfn{tunable packages} by the @option{--tune} option; a package
  9372. definition with the property set looks like this:
  9373. @lisp
  9374. (package
  9375. (name "hello-simd")
  9376. ;; ...
  9377. ;; This package may benefit from SIMD extensions so
  9378. ;; mark it as "tunable".
  9379. (properties '((tunable? . #t))))
  9380. @end lisp
  9381. Other packages are not considered tunable. This allows Guix to use
  9382. generic binaries in the cases where tuning for a specific CPU is
  9383. unlikely to provide any gain.
  9384. Tuned packages are built with @code{-march=@var{CPU}}; under the hood,
  9385. the @option{-march} option is passed to the actual wrapper by a compiler
  9386. wrapper. Since the build machine may not be able to run code for the
  9387. target CPU micro-architecture, the test suite is not run when building a
  9388. tuned package.
  9389. To reduce rebuilds to the minimum, tuned packages are @emph{grafted}
  9390. onto packages that depend on them (@pxref{Security Updates, grafts}).
  9391. Thus, using @option{--no-grafts} cancels the effect of @option{--tune}.
  9392. We call this technique @dfn{package multi-versioning}: several variants
  9393. of tunable packages may be built, one for each CPU variant. It is the
  9394. coarse-grain counterpart of @dfn{function multi-versioning} as
  9395. implemented by the GNU tool chain (@pxref{Function Multiversioning,,,
  9396. gcc, Using the GNU Compiler Collection (GCC)}).
  9397. @item --with-source=@var{source}
  9398. @itemx --with-source=@var{package}=@var{source}
  9399. @itemx --with-source=@var{package}@@@var{version}=@var{source}
  9400. Use @var{source} as the source of @var{package}, and @var{version} as
  9401. its version number.
  9402. @var{source} must be a file name or a URL, as for @command{guix
  9403. download} (@pxref{Invoking guix download}).
  9404. When @var{package} is omitted,
  9405. it is taken to be the package name specified on the
  9406. command line that matches the base of @var{source}---e.g.,
  9407. if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
  9408. package is @code{guile}.
  9409. Likewise, when @var{version} is omitted, the version string is inferred from
  9410. @var{source}; in the previous example, it is @code{2.0.10}.
  9411. This option allows users to try out versions of packages other than the
  9412. one provided by the distribution. The example below downloads
  9413. @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
  9414. the @code{ed} package:
  9415. @example
  9416. guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
  9417. @end example
  9418. As a developer, @option{--with-source} makes it easy to test release
  9419. candidates:
  9420. @example
  9421. guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
  9422. @end example
  9423. @dots{} or to build from a checkout in a pristine environment:
  9424. @example
  9425. $ git clone git://git.sv.gnu.org/guix.git
  9426. $ guix build guix --with-source=guix@@1.0=./guix
  9427. @end example
  9428. @item --with-input=@var{package}=@var{replacement}
  9429. Replace dependency on @var{package} by a dependency on
  9430. @var{replacement}. @var{package} must be a package name, and
  9431. @var{replacement} must be a package specification such as @code{guile}
  9432. or @code{guile@@1.8}.
  9433. For instance, the following command builds Guix, but replaces its
  9434. dependency on the current stable version of Guile with a dependency on
  9435. the legacy version of Guile, @code{guile@@2.0}:
  9436. @example
  9437. guix build --with-input=guile=guile@@2.0 guix
  9438. @end example
  9439. This is a recursive, deep replacement. So in this example, both
  9440. @code{guix} and its dependency @code{guile-json} (which also depends on
  9441. @code{guile}) get rebuilt against @code{guile@@2.0}.
  9442. This is implemented using the @code{package-input-rewriting} Scheme
  9443. procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
  9444. @item --with-graft=@var{package}=@var{replacement}
  9445. This is similar to @option{--with-input} but with an important difference:
  9446. instead of rebuilding the whole dependency chain, @var{replacement} is
  9447. built and then @dfn{grafted} onto the binaries that were initially
  9448. referring to @var{package}. @xref{Security Updates}, for more
  9449. information on grafts.
  9450. For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
  9451. and all its dependencies, replacing references to the version of GnuTLS
  9452. they currently refer to:
  9453. @example
  9454. guix build --with-graft=gnutls=gnutls@@3.5.4 wget
  9455. @end example
  9456. This has the advantage of being much faster than rebuilding everything.
  9457. But there is a caveat: it works if and only if @var{package} and
  9458. @var{replacement} are strictly compatible---for example, if they provide
  9459. a library, the application binary interface (ABI) of those libraries
  9460. must be compatible. If @var{replacement} is somehow incompatible with
  9461. @var{package}, then the resulting package may be unusable. Use with
  9462. care!
  9463. @cindex debugging info, rebuilding
  9464. @item --with-debug-info=@var{package}
  9465. Build @var{package} in a way that preserves its debugging info and graft
  9466. it onto packages that depend on it. This is useful if @var{package}
  9467. does not already provide debugging info as a @code{debug} output
  9468. (@pxref{Installing Debugging Files}).
  9469. For example, suppose you're experiencing a crash in Inkscape and would
  9470. like to see what's up in GLib, a library deep down in Inkscape's
  9471. dependency graph. GLib lacks a @code{debug} output, so debugging is
  9472. tough. Fortunately, you rebuild GLib with debugging info and tack it on
  9473. Inkscape:
  9474. @example
  9475. guix install inkscape --with-debug-info=glib
  9476. @end example
  9477. Only GLib needs to be recompiled so this takes a reasonable amount of
  9478. time. @xref{Installing Debugging Files}, for more info.
  9479. @quotation Note
  9480. Under the hood, this option works by passing the @samp{#:strip-binaries?
  9481. #f} to the build system of the package of interest (@pxref{Build
  9482. Systems}). Most build systems support that option but some do not. In
  9483. that case, an error is raised.
  9484. Likewise, if a C/C++ package is built without @code{-g} (which is rarely
  9485. the case), debugging info will remain unavailable even when
  9486. @code{#:strip-binaries?} is false.
  9487. @end quotation
  9488. @cindex tool chain, changing the build tool chain of a package
  9489. @item --with-c-toolchain=@var{package}=@var{toolchain}
  9490. This option changes the compilation of @var{package} and everything that
  9491. depends on it so that they get built with @var{toolchain} instead of the
  9492. default GNU tool chain for C/C++.
  9493. Consider this example:
  9494. @example
  9495. guix build octave-cli \
  9496. --with-c-toolchain=fftw=gcc-toolchain@@10 \
  9497. --with-c-toolchain=fftwf=gcc-toolchain@@10
  9498. @end example
  9499. The command above builds a variant of the @code{fftw} and @code{fftwf}
  9500. packages using version 10 of @code{gcc-toolchain} instead of the default
  9501. tool chain, and then builds a variant of the GNU@tie{}Octave
  9502. command-line interface using them. GNU@tie{}Octave itself is also built
  9503. with @code{gcc-toolchain@@10}.
  9504. This other example builds the Hardware Locality (@code{hwloc}) library
  9505. and its dependents up to @code{intel-mpi-benchmarks} with the Clang C
  9506. compiler:
  9507. @example
  9508. guix build --with-c-toolchain=hwloc=clang-toolchain \
  9509. intel-mpi-benchmarks
  9510. @end example
  9511. @quotation Note
  9512. There can be application binary interface (ABI) incompatibilities among
  9513. tool chains. This is particularly true of the C++ standard library and
  9514. run-time support libraries such as that of OpenMP@. By rebuilding all
  9515. dependents with the same tool chain, @option{--with-c-toolchain} minimizes
  9516. the risks of incompatibility but cannot entirely eliminate them. Choose
  9517. @var{package} wisely.
  9518. @end quotation
  9519. @item --with-git-url=@var{package}=@var{url}
  9520. @cindex Git, using the latest commit
  9521. @cindex latest commit, building
  9522. Build @var{package} from the latest commit of the @code{master} branch of the
  9523. Git repository at @var{url}. Git sub-modules of the repository are fetched,
  9524. recursively.
  9525. For example, the following command builds the NumPy Python library against the
  9526. latest commit of the master branch of Python itself:
  9527. @example
  9528. guix build python-numpy \
  9529. --with-git-url=python=https://github.com/python/cpython
  9530. @end example
  9531. This option can also be combined with @option{--with-branch} or
  9532. @option{--with-commit} (see below).
  9533. @cindex continuous integration
  9534. Obviously, since it uses the latest commit of the given branch, the result of
  9535. such a command varies over time. Nevertheless it is a convenient way to
  9536. rebuild entire software stacks against the latest commit of one or more
  9537. packages. This is particularly useful in the context of continuous
  9538. integration (CI).
  9539. Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
  9540. consecutive accesses to the same repository. You may want to clean it up once
  9541. in a while to save disk space.
  9542. @item --with-branch=@var{package}=@var{branch}
  9543. Build @var{package} from the latest commit of @var{branch}. If the
  9544. @code{source} field of @var{package} is an origin with the @code{git-fetch}
  9545. method (@pxref{origin Reference}) or a @code{git-checkout} object, the
  9546. repository URL is taken from that @code{source}. Otherwise you have to use
  9547. @option{--with-git-url} to specify the URL of the Git repository.
  9548. For instance, the following command builds @code{guile-sqlite3} from the
  9549. latest commit of its @code{master} branch, and then builds @code{guix} (which
  9550. depends on it) and @code{cuirass} (which depends on @code{guix}) against this
  9551. specific @code{guile-sqlite3} build:
  9552. @example
  9553. guix build --with-branch=guile-sqlite3=master cuirass
  9554. @end example
  9555. @item --with-commit=@var{package}=@var{commit}
  9556. This is similar to @option{--with-branch}, except that it builds from
  9557. @var{commit} rather than the tip of a branch. @var{commit} must be a valid
  9558. Git commit SHA1 identifier, a tag, or a @command{git describe} style
  9559. identifier such as @code{1.0-3-gabc123}.
  9560. @item --with-patch=@var{package}=@var{file}
  9561. Add @var{file} to the list of patches applied to @var{package}, where
  9562. @var{package} is a spec such as @code{python@@3.8} or @code{glibc}.
  9563. @var{file} must contain a patch; it is applied with the flags specified
  9564. in the @code{origin} of @var{package} (@pxref{origin Reference}), which
  9565. by default includes @code{-p1} (@pxref{patch Directories,,, diffutils,
  9566. Comparing and Merging Files}).
  9567. As an example, the command below rebuilds Coreutils with the GNU C
  9568. Library (glibc) patched with the given patch:
  9569. @example
  9570. guix build coreutils --with-patch=glibc=./glibc-frob.patch
  9571. @end example
  9572. In this example, glibc itself as well as everything that leads to
  9573. Coreutils in the dependency graph is rebuilt.
  9574. @cindex upstream, latest version
  9575. @item --with-latest=@var{package}
  9576. So you like living on the bleeding edge? This option is for you! It
  9577. replaces occurrences of @var{package} in the dependency graph with its
  9578. latest upstream version, as reported by @command{guix refresh}
  9579. (@pxref{Invoking guix refresh}).
  9580. It does so by determining the latest upstream release of @var{package}
  9581. (if possible), downloading it, and authenticating it @emph{if} it comes
  9582. with an OpenPGP signature.
  9583. As an example, the command below builds Guix against the latest version
  9584. of Guile-JSON:
  9585. @example
  9586. guix build guix --with-latest=guile-json
  9587. @end example
  9588. There are limitations. First, in cases where the tool cannot or does
  9589. not know how to authenticate source code, you are at risk of running
  9590. malicious code; a warning is emitted in this case. Second, this option
  9591. simply changes the source used in the existing package definitions,
  9592. which is not always sufficient: there might be additional dependencies
  9593. that need to be added, patches to apply, and more generally the quality
  9594. assurance work that Guix developers normally do will be missing.
  9595. You've been warned! In all the other cases, it's a snappy way to stay
  9596. on top. We encourage you to submit patches updating the actual package
  9597. definitions once you have successfully tested an upgrade
  9598. (@pxref{Contributing}).
  9599. @cindex test suite, skipping
  9600. @item --without-tests=@var{package}
  9601. Build @var{package} without running its tests. This can be useful in
  9602. situations where you want to skip the lengthy test suite of a
  9603. intermediate package, or if a package's test suite fails in a
  9604. non-deterministic fashion. It should be used with care because running
  9605. the test suite is a good way to ensure a package is working as intended.
  9606. Turning off tests leads to a different store item. Consequently, when
  9607. using this option, anything that depends on @var{package} must be
  9608. rebuilt, as in this example:
  9609. @example
  9610. guix install --without-tests=python python-notebook
  9611. @end example
  9612. The command above installs @code{python-notebook} on top of
  9613. @code{python} built without running its test suite. To do so, it also
  9614. rebuilds everything that depends on @code{python}, including
  9615. @code{python-notebook} itself.
  9616. Internally, @option{--without-tests} relies on changing the
  9617. @code{#:tests?} option of a package's @code{check} phase (@pxref{Build
  9618. Systems}). Note that some packages use a customized @code{check} phase
  9619. that does not respect a @code{#:tests? #f} setting. Therefore,
  9620. @option{--without-tests} has no effect on these packages.
  9621. @end table
  9622. Wondering how to achieve the same effect using Scheme code, for example
  9623. in your manifest, or how to write your own package transformation?
  9624. @xref{Defining Package Variants}, for an overview of the programming
  9625. interfaces available.
  9626. @node Additional Build Options
  9627. @subsection Additional Build Options
  9628. The command-line options presented below are specific to @command{guix
  9629. build}.
  9630. @table @code
  9631. @item --quiet
  9632. @itemx -q
  9633. Build quietly, without displaying the build log; this is equivalent to
  9634. @option{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
  9635. (or similar) and can always be retrieved using the @option{--log-file} option.
  9636. @item --file=@var{file}
  9637. @itemx -f @var{file}
  9638. Build the package, derivation, or other file-like object that the code within
  9639. @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
  9640. As an example, @var{file} might contain a package definition like this
  9641. (@pxref{Defining Packages}):
  9642. @lisp
  9643. @include package-hello.scm
  9644. @end lisp
  9645. The @var{file} may also contain a JSON representation of one or more
  9646. package definitions. Running @code{guix build -f} on @file{hello.json}
  9647. with the following contents would result in building the packages
  9648. @code{myhello} and @code{greeter}:
  9649. @example
  9650. @verbatiminclude package-hello.json
  9651. @end example
  9652. @item --manifest=@var{manifest}
  9653. @itemx -m @var{manifest}
  9654. Build all packages listed in the given @var{manifest}
  9655. (@pxref{profile-manifest, @option{--manifest}}).
  9656. @item --expression=@var{expr}
  9657. @itemx -e @var{expr}
  9658. Build the package or derivation @var{expr} evaluates to.
  9659. For example, @var{expr} may be @code{(@@ (gnu packages guile)
  9660. guile-1.8)}, which unambiguously designates this specific variant of
  9661. version 1.8 of Guile.
  9662. Alternatively, @var{expr} may be a G-expression, in which case it is used
  9663. as a build program passed to @code{gexp->derivation}
  9664. (@pxref{G-Expressions}).
  9665. Lastly, @var{expr} may refer to a zero-argument monadic procedure
  9666. (@pxref{The Store Monad}). The procedure must return a derivation as a
  9667. monadic value, which is then passed through @code{run-with-store}.
  9668. @item --source
  9669. @itemx -S
  9670. Build the source derivations of the packages, rather than the packages
  9671. themselves.
  9672. For instance, @code{guix build -S gcc} returns something like
  9673. @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
  9674. source tarball.
  9675. The returned source tarball is the result of applying any patches and
  9676. code snippets specified in the package @code{origin} (@pxref{Defining
  9677. Packages}).
  9678. @cindex source, verification
  9679. As with other derivations, the result of building a source derivation
  9680. can be verified using the @option{--check} option (@pxref{build-check}).
  9681. This is useful to validate that a (potentially already built or
  9682. substituted, thus cached) package source matches against its declared
  9683. hash.
  9684. Note that @command{guix build -S} compiles the sources only of the
  9685. specified packages. They do not include the sources of statically
  9686. linked dependencies and by themselves are insufficient for reproducing
  9687. the packages.
  9688. @item --sources
  9689. Fetch and return the source of @var{package-or-derivation} and all their
  9690. dependencies, recursively. This is a handy way to obtain a local copy
  9691. of all the source code needed to build @var{packages}, allowing you to
  9692. eventually build them even without network access. It is an extension
  9693. of the @option{--source} option and can accept one of the following
  9694. optional argument values:
  9695. @table @code
  9696. @item package
  9697. This value causes the @option{--sources} option to behave in the same way
  9698. as the @option{--source} option.
  9699. @item all
  9700. Build the source derivations of all packages, including any source that
  9701. might be listed as @code{inputs}. This is the default value.
  9702. @example
  9703. $ guix build --sources tzdata
  9704. The following derivations will be built:
  9705. /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
  9706. /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
  9707. @end example
  9708. @item transitive
  9709. Build the source derivations of all packages, as well of all transitive
  9710. inputs to the packages. This can be used e.g.@: to
  9711. prefetch package source for later offline building.
  9712. @example
  9713. $ guix build --sources=transitive tzdata
  9714. The following derivations will be built:
  9715. /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
  9716. /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
  9717. /gnu/store/@dots{}-grep-2.21.tar.xz.drv
  9718. /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
  9719. /gnu/store/@dots{}-make-4.1.tar.xz.drv
  9720. /gnu/store/@dots{}-bash-4.3.tar.xz.drv
  9721. @dots{}
  9722. @end example
  9723. @end table
  9724. @item --system=@var{system}
  9725. @itemx -s @var{system}
  9726. Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
  9727. the system type of the build host. The @command{guix build} command allows
  9728. you to repeat this option several times, in which case it builds for all the
  9729. specified systems; other commands ignore extraneous @option{-s} options.
  9730. @quotation Note
  9731. The @option{--system} flag is for @emph{native} compilation and must not
  9732. be confused with cross-compilation. See @option{--target} below for
  9733. information on cross-compilation.
  9734. @end quotation
  9735. An example use of this is on Linux-based systems, which can emulate
  9736. different personalities. For instance, passing
  9737. @option{--system=i686-linux} on an @code{x86_64-linux} system or
  9738. @option{--system=armhf-linux} on an @code{aarch64-linux} system allows
  9739. you to build packages in a complete 32-bit environment.
  9740. @quotation Note
  9741. Building for an @code{armhf-linux} system is unconditionally enabled on
  9742. @code{aarch64-linux} machines, although certain aarch64 chipsets do not
  9743. allow for this functionality, notably the ThunderX.
  9744. @end quotation
  9745. Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
  9746. is enabled (@pxref{Virtualization Services,
  9747. @code{qemu-binfmt-service-type}}), you can build for any system for
  9748. which a QEMU @code{binfmt_misc} handler is installed.
  9749. Builds for a system other than that of the machine you are using can
  9750. also be offloaded to a remote machine of the right architecture.
  9751. @xref{Daemon Offload Setup}, for more information on offloading.
  9752. @item --target=@var{triplet}
  9753. @cindex cross-compilation
  9754. Cross-build for @var{triplet}, which must be a valid GNU triplet, such
  9755. as @code{"aarch64-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
  9756. configuration triplets,, autoconf, Autoconf}).
  9757. @anchor{build-check}
  9758. @item --check
  9759. @cindex determinism, checking
  9760. @cindex reproducibility, checking
  9761. Rebuild @var{package-or-derivation}, which are already available in the
  9762. store, and raise an error if the build results are not bit-for-bit
  9763. identical.
  9764. This mechanism allows you to check whether previously installed
  9765. substitutes are genuine (@pxref{Substitutes}), or whether the build result
  9766. of a package is deterministic. @xref{Invoking guix challenge}, for more
  9767. background information and tools.
  9768. When used in conjunction with @option{--keep-failed}, the differing
  9769. output is kept in the store, under @file{/gnu/store/@dots{}-check}.
  9770. This makes it easy to look for differences between the two results.
  9771. @item --repair
  9772. @cindex repairing store items
  9773. @cindex corruption, recovering from
  9774. Attempt to repair the specified store items, if they are corrupt, by
  9775. re-downloading or rebuilding them.
  9776. This operation is not atomic and thus restricted to @code{root}.
  9777. @item --derivations
  9778. @itemx -d
  9779. Return the derivation paths, not the output paths, of the given
  9780. packages.
  9781. @item --root=@var{file}
  9782. @itemx -r @var{file}
  9783. @cindex GC roots, adding
  9784. @cindex garbage collector roots, adding
  9785. Make @var{file} a symlink to the result, and register it as a garbage
  9786. collector root.
  9787. Consequently, the results of this @command{guix build} invocation are
  9788. protected from garbage collection until @var{file} is removed. When
  9789. that option is omitted, build results are eligible for garbage
  9790. collection as soon as the build completes. @xref{Invoking guix gc}, for
  9791. more on GC roots.
  9792. @item --log-file
  9793. @cindex build logs, access
  9794. Return the build log file names or URLs for the given
  9795. @var{package-or-derivation}, or raise an error if build logs are
  9796. missing.
  9797. This works regardless of how packages or derivations are specified. For
  9798. instance, the following invocations are equivalent:
  9799. @example
  9800. guix build --log-file $(guix build -d guile)
  9801. guix build --log-file $(guix build guile)
  9802. guix build --log-file guile
  9803. guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
  9804. @end example
  9805. If a log is unavailable locally, and unless @option{--no-substitutes} is
  9806. passed, the command looks for a corresponding log on one of the
  9807. substitute servers (as specified with @option{--substitute-urls}).
  9808. So for instance, imagine you want to see the build log of GDB on MIPS,
  9809. but you are actually on an @code{x86_64} machine:
  9810. @example
  9811. $ guix build --log-file gdb -s aarch64-linux
  9812. https://@value{SUBSTITUTE-SERVER-1}/log/@dots{}-gdb-7.10
  9813. @end example
  9814. You can freely access a huge library of build logs!
  9815. @end table
  9816. @node Debugging Build Failures
  9817. @subsection Debugging Build Failures
  9818. @cindex build failures, debugging
  9819. When defining a new package (@pxref{Defining Packages}), you will
  9820. probably find yourself spending some time debugging and tweaking the
  9821. build until it succeeds. To do that, you need to operate the build
  9822. commands yourself in an environment as close as possible to the one the
  9823. build daemon uses.
  9824. To that end, the first thing to do is to use the @option{--keep-failed}
  9825. or @option{-K} option of @command{guix build}, which will keep the
  9826. failed build tree in @file{/tmp} or whatever directory you specified as
  9827. @env{TMPDIR} (@pxref{Common Build Options, @option{--keep-failed}}).
  9828. From there on, you can @command{cd} to the failed build tree and source
  9829. the @file{environment-variables} file, which contains all the
  9830. environment variable definitions that were in place when the build
  9831. failed. So let's say you're debugging a build failure in package
  9832. @code{foo}; a typical session would look like this:
  9833. @example
  9834. $ guix build foo -K
  9835. @dots{} @i{build fails}
  9836. $ cd /tmp/guix-build-foo.drv-0
  9837. $ source ./environment-variables
  9838. $ cd foo-1.2
  9839. @end example
  9840. Now, you can invoke commands as if you were the daemon (almost) and
  9841. troubleshoot your build process.
  9842. Sometimes it happens that, for example, a package's tests pass when you
  9843. run them manually but they fail when the daemon runs them. This can
  9844. happen because the daemon runs builds in containers where, unlike in our
  9845. environment above, network access is missing, @file{/bin/sh} does not
  9846. exist, etc. (@pxref{Build Environment Setup}).
  9847. In such cases, you may need to run inspect the build process from within
  9848. a container similar to the one the build daemon creates:
  9849. @example
  9850. $ guix build -K foo
  9851. @dots{}
  9852. $ cd /tmp/guix-build-foo.drv-0
  9853. $ guix shell --no-grafts -C -D foo strace gdb
  9854. [env]# source ./environment-variables
  9855. [env]# cd foo-1.2
  9856. @end example
  9857. Here, @command{guix shell -C} creates a container and spawns a new
  9858. shell in it (@pxref{Invoking guix shell}). The @command{strace gdb}
  9859. part adds the @command{strace} and @command{gdb} commands to
  9860. the container, which you may find handy while debugging. The
  9861. @option{--no-grafts} option makes sure we get the exact same
  9862. environment, with ungrafted packages (@pxref{Security Updates}, for more
  9863. info on grafts).
  9864. To get closer to a container like that used by the build daemon, we can
  9865. remove @file{/bin/sh}:
  9866. @example
  9867. [env]# rm /bin/sh
  9868. @end example
  9869. (Don't worry, this is harmless: this is all happening in the throw-away
  9870. container created by @command{guix shell}.)
  9871. The @command{strace} command is probably not in the search path, but we
  9872. can run:
  9873. @example
  9874. [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
  9875. @end example
  9876. In this way, not only you will have reproduced the environment variables
  9877. the daemon uses, you will also be running the build process in a container
  9878. similar to the one the daemon uses.
  9879. @node Invoking guix edit
  9880. @section Invoking @command{guix edit}
  9881. @cindex @command{guix edit}
  9882. @cindex package definition, editing
  9883. So many packages, so many source files! The @command{guix edit} command
  9884. facilitates the life of users and packagers by pointing their editor at
  9885. the source file containing the definition of the specified packages.
  9886. For instance:
  9887. @example
  9888. guix edit gcc@@4.9 vim
  9889. @end example
  9890. @noindent
  9891. launches the program specified in the @env{VISUAL} or in the
  9892. @env{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
  9893. and that of Vim.
  9894. If you are using a Guix Git checkout (@pxref{Building from Git}), or
  9895. have created your own packages on @env{GUIX_PACKAGE_PATH}
  9896. (@pxref{Package Modules}), you will be able to edit the package
  9897. recipes. In other cases, you will be able to examine the read-only recipes
  9898. for packages currently in the store.
  9899. Instead of @env{GUIX_PACKAGE_PATH}, the command-line option
  9900. @option{--load-path=@var{directory}} (or in short @option{-L
  9901. @var{directory}}) allows you to add @var{directory} to the front of the
  9902. package module search path and so make your own packages visible.
  9903. @node Invoking guix download
  9904. @section Invoking @command{guix download}
  9905. @cindex @command{guix download}
  9906. @cindex downloading package sources
  9907. When writing a package definition, developers typically need to download
  9908. a source tarball, compute its SHA256 hash, and write that
  9909. hash in the package definition (@pxref{Defining Packages}). The
  9910. @command{guix download} tool helps with this task: it downloads a file
  9911. from the given URI, adds it to the store, and prints both its file name
  9912. in the store and its SHA256 hash.
  9913. The fact that the downloaded file is added to the store saves bandwidth:
  9914. when the developer eventually tries to build the newly defined package
  9915. with @command{guix build}, the source tarball will not have to be
  9916. downloaded again because it is already in the store. It is also a
  9917. convenient way to temporarily stash files, which may be deleted
  9918. eventually (@pxref{Invoking guix gc}).
  9919. The @command{guix download} command supports the same URIs as used in
  9920. package definitions. In particular, it supports @code{mirror://} URIs.
  9921. @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
  9922. Guile bindings for GnuTLS are available in the user's environment; when
  9923. they are not available, an error is raised. @xref{Guile Preparations,
  9924. how to install the GnuTLS bindings for Guile,, gnutls-guile,
  9925. GnuTLS-Guile}, for more information.
  9926. @command{guix download} verifies HTTPS server certificates by loading
  9927. the certificates of X.509 authorities from the directory pointed to by
  9928. the @env{SSL_CERT_DIR} environment variable (@pxref{X.509
  9929. Certificates}), unless @option{--no-check-certificate} is used.
  9930. The following options are available:
  9931. @table @code
  9932. @item --hash=@var{algorithm}
  9933. @itemx -H @var{algorithm}
  9934. Compute a hash using the specified @var{algorithm}. @xref{Invoking guix
  9935. hash}, for more information.
  9936. @item --format=@var{fmt}
  9937. @itemx -f @var{fmt}
  9938. Write the hash in the format specified by @var{fmt}. For more
  9939. information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
  9940. @item --no-check-certificate
  9941. Do not validate the X.509 certificates of HTTPS servers.
  9942. When using this option, you have @emph{absolutely no guarantee} that you
  9943. are communicating with the authentic server responsible for the given
  9944. URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
  9945. @item --output=@var{file}
  9946. @itemx -o @var{file}
  9947. Save the downloaded file to @var{file} instead of adding it to the
  9948. store.
  9949. @end table
  9950. @node Invoking guix hash
  9951. @section Invoking @command{guix hash}
  9952. @cindex @command{guix hash}
  9953. The @command{guix hash} command computes the hash of a file.
  9954. It is primarily a convenience tool for anyone contributing to the
  9955. distribution: it computes the cryptographic hash of one or more files, which can be
  9956. used in the definition of a package (@pxref{Defining Packages}).
  9957. The general syntax is:
  9958. @example
  9959. guix hash @var{option} @var{file} ...
  9960. @end example
  9961. When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
  9962. hash of data read from standard input. @command{guix hash} has the
  9963. following options:
  9964. @table @code
  9965. @item --hash=@var{algorithm}
  9966. @itemx -H @var{algorithm}
  9967. Compute a hash using the specified @var{algorithm}, @code{sha256} by
  9968. default.
  9969. @var{algorithm} must be the name of a cryptographic hash algorithm
  9970. supported by Libgcrypt @i{via} Guile-Gcrypt---e.g., @code{sha512} or
  9971. @code{sha3-256} (@pxref{Hash Functions,,, guile-gcrypt, Guile-Gcrypt
  9972. Reference Manual}).
  9973. @item --format=@var{fmt}
  9974. @itemx -f @var{fmt}
  9975. Write the hash in the format specified by @var{fmt}.
  9976. Supported formats: @code{base64}, @code{nix-base32}, @code{base32}, @code{base16}
  9977. (@code{hex} and @code{hexadecimal} can be used as well).
  9978. If the @option{--format} option is not specified, @command{guix hash}
  9979. will output the hash in @code{nix-base32}. This representation is used
  9980. in the definitions of packages.
  9981. @item --recursive
  9982. @itemx -r
  9983. The @option{--recursive} option is deprecated in favor of
  9984. @option{--serializer=nar} (see below); @option{-r} remains accepted as a
  9985. convenient shorthand.
  9986. @item --serializer=@var{type}
  9987. @itemx -S @var{type}
  9988. Compute the hash on @var{file} using @var{type} serialization.
  9989. @var{type} may be one of the following:
  9990. @table @code
  9991. @item none
  9992. This is the default: it computes the hash of a file's contents.
  9993. @item nar
  9994. Compute the hash of a ``normalized archive'' (or ``nar'') containing
  9995. @var{file}, including its children if it is a directory. Some of the
  9996. metadata of @var{file} is part of the archive; for instance, when
  9997. @var{file} is a regular file, the hash is different depending on whether
  9998. @var{file} is executable or not. Metadata such as time stamps have no
  9999. impact on the hash (@pxref{Invoking guix archive}, for more info on the
  10000. nar format).
  10001. @c FIXME: Replace xref above with xref to an ``Archive'' section when
  10002. @c it exists.
  10003. @item git
  10004. Compute the hash of the file or directory as a Git ``tree'', following
  10005. the same method as the Git version control system.
  10006. @end table
  10007. @item --exclude-vcs
  10008. @itemx -x
  10009. When combined with @option{--recursive}, exclude version control system
  10010. directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.).
  10011. @vindex git-fetch
  10012. As an example, here is how you would compute the hash of a Git checkout,
  10013. which is useful when using the @code{git-fetch} method (@pxref{origin
  10014. Reference}):
  10015. @example
  10016. $ git clone http://example.org/foo.git
  10017. $ cd foo
  10018. $ guix hash -x --serializer=nar .
  10019. @end example
  10020. @end table
  10021. @node Invoking guix import
  10022. @section Invoking @command{guix import}
  10023. @cindex importing packages
  10024. @cindex package import
  10025. @cindex package conversion
  10026. @cindex Invoking @command{guix import}
  10027. The @command{guix import} command is useful for people who would like to
  10028. add a package to the distribution with as little work as
  10029. possible---a legitimate demand. The command knows of a few
  10030. repositories from which it can ``import'' package metadata. The result
  10031. is a package definition, or a template thereof, in the format we know
  10032. (@pxref{Defining Packages}).
  10033. The general syntax is:
  10034. @example
  10035. guix import @var{importer} @var{options}@dots{}
  10036. @end example
  10037. @var{importer} specifies the source from which to import package
  10038. metadata, and @var{options} specifies a package identifier and other
  10039. options specific to @var{importer}.
  10040. Some of the importers rely on the ability to run the @command{gpgv} command.
  10041. For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
  10042. gnupg} if needed.
  10043. Currently, the available ``importers'' are:
  10044. @table @code
  10045. @item gnu
  10046. Import metadata for the given GNU package. This provides a template
  10047. for the latest version of that GNU package, including the hash of its
  10048. source tarball, and its canonical synopsis and description.
  10049. Additional information such as the package dependencies and its
  10050. license needs to be figured out manually.
  10051. For example, the following command returns a package definition for
  10052. GNU@tie{}Hello:
  10053. @example
  10054. guix import gnu hello
  10055. @end example
  10056. Specific command-line options are:
  10057. @table @code
  10058. @item --key-download=@var{policy}
  10059. As for @command{guix refresh}, specify the policy to handle missing
  10060. OpenPGP keys when verifying the package signature. @xref{Invoking guix
  10061. refresh, @option{--key-download}}.
  10062. @end table
  10063. @item pypi
  10064. @cindex pypi
  10065. Import metadata from the @uref{https://pypi.python.org/, Python Package
  10066. Index}. Information is taken from the JSON-formatted description
  10067. available at @code{pypi.python.org} and usually includes all the relevant
  10068. information, including package dependencies. For maximum efficiency, it
  10069. is recommended to install the @command{unzip} utility, so that the
  10070. importer can unzip Python wheels and gather data from them.
  10071. The command below imports metadata for the latest version of the
  10072. @code{itsdangerous} Python package:
  10073. @example
  10074. guix import pypi itsdangerous
  10075. @end example
  10076. You can also ask for a specific version:
  10077. @example
  10078. guix import pypi itsdangerous@@1.1.0
  10079. @end example
  10080. @table @code
  10081. @item --recursive
  10082. @itemx -r
  10083. Traverse the dependency graph of the given upstream package recursively
  10084. and generate package expressions for all those packages that are not yet
  10085. in Guix.
  10086. @end table
  10087. @item gem
  10088. @cindex gem
  10089. Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
  10090. is taken from the JSON-formatted description available at
  10091. @code{rubygems.org} and includes most relevant information, including
  10092. runtime dependencies. There are some caveats, however. The metadata
  10093. doesn't distinguish between synopses and descriptions, so the same string
  10094. is used for both fields. Additionally, the details of non-Ruby
  10095. dependencies required to build native extensions is unavailable and left
  10096. as an exercise to the packager.
  10097. The command below imports metadata for the @code{rails} Ruby package:
  10098. @example
  10099. guix import gem rails
  10100. @end example
  10101. @table @code
  10102. @item --recursive
  10103. @itemx -r
  10104. Traverse the dependency graph of the given upstream package recursively
  10105. and generate package expressions for all those packages that are not yet
  10106. in Guix.
  10107. @end table
  10108. @item minetest
  10109. @cindex minetest
  10110. @cindex ContentDB
  10111. Import metadata from @uref{https://content.minetest.net, ContentDB}.
  10112. Information is taken from the JSON-formatted metadata provided through
  10113. @uref{https://content.minetest.net/help/api/, ContentDB's API} and
  10114. includes most relevant information, including dependencies. There are
  10115. some caveats, however. The license information is often incomplete.
  10116. The commit hash is sometimes missing. The descriptions are in the
  10117. Markdown format, but Guix uses Texinfo instead. Texture packs and
  10118. subgames are unsupported.
  10119. The command below imports metadata for the Mesecons mod by Jeija:
  10120. @example
  10121. guix import minetest Jeija/mesecons
  10122. @end example
  10123. The author name can also be left out:
  10124. @example
  10125. guix import minetest mesecons
  10126. @end example
  10127. @table @code
  10128. @item --recursive
  10129. @itemx -r
  10130. Traverse the dependency graph of the given upstream package recursively
  10131. and generate package expressions for all those packages that are not yet
  10132. in Guix.
  10133. @end table
  10134. @item cpan
  10135. @cindex CPAN
  10136. Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
  10137. Information is taken from the JSON-formatted metadata provided through
  10138. @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
  10139. relevant information, such as module dependencies. License information
  10140. should be checked closely. If Perl is available in the store, then the
  10141. @code{corelist} utility will be used to filter core modules out of the
  10142. list of dependencies.
  10143. The command command below imports metadata for the Acme::Boolean Perl
  10144. module:
  10145. @example
  10146. guix import cpan Acme::Boolean
  10147. @end example
  10148. @item cran
  10149. @cindex CRAN
  10150. @cindex Bioconductor
  10151. Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
  10152. central repository for the @uref{https://r-project.org, GNU@tie{}R
  10153. statistical and graphical environment}.
  10154. Information is extracted from the @file{DESCRIPTION} file of the package.
  10155. The command command below imports metadata for the Cairo R package:
  10156. @example
  10157. guix import cran Cairo
  10158. @end example
  10159. You can also ask for a specific version:
  10160. @example
  10161. guix import cran rasterVis@@0.50.3
  10162. @end example
  10163. When @option{--recursive} is added, the importer will traverse the
  10164. dependency graph of the given upstream package recursively and generate
  10165. package expressions for all those packages that are not yet in Guix.
  10166. When @option{--style=specification} is added, the importer will generate
  10167. package definitions whose inputs are package specifications instead of
  10168. references to package variables. This is useful when generated package
  10169. definitions are to be appended to existing user modules, as the list of
  10170. used package modules need not be changed. The default is
  10171. @option{--style=variable}.
  10172. When @option{--archive=bioconductor} is added, metadata is imported from
  10173. @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
  10174. packages for the analysis and comprehension of high-throughput
  10175. genomic data in bioinformatics.
  10176. Information is extracted from the @file{DESCRIPTION} file contained in the
  10177. package archive.
  10178. The command below imports metadata for the GenomicRanges R package:
  10179. @example
  10180. guix import cran --archive=bioconductor GenomicRanges
  10181. @end example
  10182. Finally, you can also import R packages that have not yet been published on
  10183. CRAN or Bioconductor as long as they are in a git repository. Use
  10184. @option{--archive=git} followed by the URL of the git repository:
  10185. @example
  10186. guix import cran --archive=git https://github.com/immunogenomics/harmony
  10187. @end example
  10188. @item texlive
  10189. @cindex TeX Live
  10190. @cindex CTAN
  10191. Import TeX package information from the TeX Live package database for
  10192. TeX packages that are part of the @uref{https://www.tug.org/texlive/,
  10193. TeX Live distribution}.
  10194. Information about the package is obtained from the TeX Live package
  10195. database, a plain text file that is included in the @code{texlive-bin}
  10196. package. The source code is downloaded from possibly multiple locations
  10197. in the SVN repository of the Tex Live project.
  10198. The command command below imports metadata for the @code{fontspec}
  10199. TeX package:
  10200. @example
  10201. guix import texlive fontspec
  10202. @end example
  10203. @item json
  10204. @cindex JSON, import
  10205. Import package metadata from a local JSON file. Consider the following
  10206. example package definition in JSON format:
  10207. @example
  10208. @{
  10209. "name": "hello",
  10210. "version": "2.10",
  10211. "source": "mirror://gnu/hello/hello-2.10.tar.gz",
  10212. "build-system": "gnu",
  10213. "home-page": "https://www.gnu.org/software/hello/",
  10214. "synopsis": "Hello, GNU world: An example GNU package",
  10215. "description": "GNU Hello prints a greeting.",
  10216. "license": "GPL-3.0+",
  10217. "native-inputs": ["gettext"]
  10218. @}
  10219. @end example
  10220. The field names are the same as for the @code{<package>} record
  10221. (@xref{Defining Packages}). References to other packages are provided
  10222. as JSON lists of quoted package specification strings such as
  10223. @code{guile} or @code{guile@@2.0}.
  10224. The importer also supports a more explicit source definition using the
  10225. common fields for @code{<origin>} records:
  10226. @example
  10227. @{
  10228. @dots{}
  10229. "source": @{
  10230. "method": "url-fetch",
  10231. "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
  10232. "sha256": @{
  10233. "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
  10234. @}
  10235. @}
  10236. @dots{}
  10237. @}
  10238. @end example
  10239. The command below reads metadata from the JSON file @code{hello.json}
  10240. and outputs a package expression:
  10241. @example
  10242. guix import json hello.json
  10243. @end example
  10244. @item hackage
  10245. @cindex hackage
  10246. Import metadata from the Haskell community's central package archive
  10247. @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
  10248. Cabal files and includes all the relevant information, including package
  10249. dependencies.
  10250. Specific command-line options are:
  10251. @table @code
  10252. @item --stdin
  10253. @itemx -s
  10254. Read a Cabal file from standard input.
  10255. @item --no-test-dependencies
  10256. @itemx -t
  10257. Do not include dependencies required only by the test suites.
  10258. @item --cabal-environment=@var{alist}
  10259. @itemx -e @var{alist}
  10260. @var{alist} is a Scheme alist defining the environment in which the
  10261. Cabal conditionals are evaluated. The accepted keys are: @code{os},
  10262. @code{arch}, @code{impl} and a string representing the name of a flag.
  10263. The value associated with a flag has to be either the symbol
  10264. @code{true} or @code{false}. The value associated with other keys
  10265. has to conform to the Cabal file format definition. The default value
  10266. associated with the keys @code{os}, @code{arch} and @code{impl} is
  10267. @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
  10268. @item --recursive
  10269. @itemx -r
  10270. Traverse the dependency graph of the given upstream package recursively
  10271. and generate package expressions for all those packages that are not yet
  10272. in Guix.
  10273. @end table
  10274. The command below imports metadata for the latest version of the
  10275. HTTP Haskell package without including test dependencies and
  10276. specifying the value of the flag @samp{network-uri} as @code{false}:
  10277. @example
  10278. guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
  10279. @end example
  10280. A specific package version may optionally be specified by following the
  10281. package name by an at-sign and a version number as in the following example:
  10282. @example
  10283. guix import hackage mtl@@2.1.3.1
  10284. @end example
  10285. @item stackage
  10286. @cindex stackage
  10287. The @code{stackage} importer is a wrapper around the @code{hackage} one.
  10288. It takes a package name, looks up the package version included in a
  10289. long-term support (LTS) @uref{https://www.stackage.org, Stackage}
  10290. release and uses the @code{hackage} importer to retrieve its metadata.
  10291. Note that it is up to you to select an LTS release compatible with the
  10292. GHC compiler used by Guix.
  10293. Specific command-line options are:
  10294. @table @code
  10295. @item --no-test-dependencies
  10296. @itemx -t
  10297. Do not include dependencies required only by the test suites.
  10298. @item --lts-version=@var{version}
  10299. @itemx -l @var{version}
  10300. @var{version} is the desired LTS release version. If omitted the latest
  10301. release is used.
  10302. @item --recursive
  10303. @itemx -r
  10304. Traverse the dependency graph of the given upstream package recursively
  10305. and generate package expressions for all those packages that are not yet
  10306. in Guix.
  10307. @end table
  10308. The command below imports metadata for the HTTP Haskell package
  10309. included in the LTS Stackage release version 7.18:
  10310. @example
  10311. guix import stackage --lts-version=7.18 HTTP
  10312. @end example
  10313. @item elpa
  10314. @cindex elpa
  10315. Import metadata from an Emacs Lisp Package Archive (ELPA) package
  10316. repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
  10317. Specific command-line options are:
  10318. @table @code
  10319. @item --archive=@var{repo}
  10320. @itemx -a @var{repo}
  10321. @var{repo} identifies the archive repository from which to retrieve the
  10322. information. Currently the supported repositories and their identifiers
  10323. are:
  10324. @itemize -
  10325. @item
  10326. @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
  10327. identifier. This is the default.
  10328. Packages from @code{elpa.gnu.org} are signed with one of the keys
  10329. contained in the GnuPG keyring at
  10330. @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
  10331. @code{emacs} package (@pxref{Package Installation, ELPA package
  10332. signatures,, emacs, The GNU Emacs Manual}).
  10333. @item
  10334. @uref{https://elpa.nongnu.org/nongnu/, NonGNU}, selected by the
  10335. @code{nongnu} identifier.
  10336. @item
  10337. @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
  10338. @code{melpa-stable} identifier.
  10339. @item
  10340. @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
  10341. identifier.
  10342. @end itemize
  10343. @item --recursive
  10344. @itemx -r
  10345. Traverse the dependency graph of the given upstream package recursively
  10346. and generate package expressions for all those packages that are not yet
  10347. in Guix.
  10348. @end table
  10349. @item crate
  10350. @cindex crate
  10351. Import metadata from the crates.io Rust package repository
  10352. @uref{https://crates.io, crates.io}, as in this example:
  10353. @example
  10354. guix import crate blake2-rfc
  10355. @end example
  10356. The crate importer also allows you to specify a version string:
  10357. @example
  10358. guix import crate constant-time-eq@@0.1.0
  10359. @end example
  10360. Additional options include:
  10361. @table @code
  10362. @item --recursive
  10363. @itemx -r
  10364. Traverse the dependency graph of the given upstream package recursively
  10365. and generate package expressions for all those packages that are not yet
  10366. in Guix.
  10367. @end table
  10368. @item opam
  10369. @cindex OPAM
  10370. @cindex OCaml
  10371. Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
  10372. repository used by the OCaml community.
  10373. Additional options include:
  10374. @table @code
  10375. @item --recursive
  10376. @itemx -r
  10377. Traverse the dependency graph of the given upstream package recursively
  10378. and generate package expressions for all those packages that are not yet
  10379. in Guix.
  10380. @item --repo
  10381. By default, packages are searched in the official OPAM repository. This
  10382. option, which can be used more than once, lets you add other repositories
  10383. which will be searched for packages. It accepts as valid arguments:
  10384. @itemize
  10385. @item the name of a known repository - can be one of @code{opam},
  10386. @code{coq} (equivalent to @code{coq-released}),
  10387. @code{coq-core-dev}, @code{coq-extra-dev} or @code{grew}.
  10388. @item the URL of a repository as expected by the
  10389. @code{opam repository add} command (for instance, the URL equivalent
  10390. of the above @code{opam} name would be
  10391. @uref{https://opam.ocaml.org}).
  10392. @item the path to a local copy of a repository (a directory containing a
  10393. @file{packages/} sub-directory).
  10394. @end itemize
  10395. Repositories are assumed to be passed to this option by order of
  10396. preference. The additional repositories will not replace the default
  10397. @code{opam} repository, which is always kept as a fallback.
  10398. Also, please note that versions are not compared across repositories.
  10399. The first repository (from left to right) that has at least one version
  10400. of a given package will prevail over any others, and the version
  10401. imported will be the latest one found @emph{in this repository only}.
  10402. @end table
  10403. @item go
  10404. @cindex go
  10405. Import metadata for a Go module using
  10406. @uref{https://proxy.golang.org, proxy.golang.org}.
  10407. @example
  10408. guix import go gopkg.in/yaml.v2
  10409. @end example
  10410. It is possible to use a package specification with a @code{@@VERSION}
  10411. suffix to import a specific version.
  10412. Additional options include:
  10413. @table @code
  10414. @item --recursive
  10415. @itemx -r
  10416. Traverse the dependency graph of the given upstream package recursively
  10417. and generate package expressions for all those packages that are not yet
  10418. in Guix.
  10419. @item --pin-versions
  10420. When using this option, the importer preserves the exact versions of the
  10421. Go modules dependencies instead of using their latest available
  10422. versions. This can be useful when attempting to import packages that
  10423. recursively depend on former versions of themselves to build. When
  10424. using this mode, the symbol of the package is made by appending the
  10425. version to its name, so that multiple versions of the same package can
  10426. coexist.
  10427. @end table
  10428. @item egg
  10429. @cindex egg
  10430. Import metadata for @uref{https://wiki.call-cc.org/eggs, CHICKEN eggs}.
  10431. The information is taken from @file{PACKAGE.egg} files found in the
  10432. @uref{git://code.call-cc.org/eggs-5-all, eggs-5-all} Git
  10433. repository. However, it does not provide all the information that we
  10434. need, there is no ``description'' field, and the licenses used are not
  10435. always precise (BSD is often used instead of BSD-N).
  10436. @example
  10437. guix import egg sourcehut
  10438. @end example
  10439. You can also ask for a specific version:
  10440. @example
  10441. guix import egg arrays@@1.0
  10442. @end example
  10443. Additional options include:
  10444. @table @code
  10445. @item --recursive
  10446. @itemx -r
  10447. Traverse the dependency graph of the given upstream package recursively
  10448. and generate package expressions for all those packages that are not yet
  10449. in Guix.
  10450. @end table
  10451. @end table
  10452. The structure of the @command{guix import} code is modular. It would be
  10453. useful to have more importers for other package formats, and your help
  10454. is welcome here (@pxref{Contributing}).
  10455. @node Invoking guix refresh
  10456. @section Invoking @command{guix refresh}
  10457. @cindex @command {guix refresh}
  10458. The primary audience of the @command{guix refresh} command is packagers.
  10459. As a user, you may be interested in the @option{--with-latest} option,
  10460. which can bring you package update superpowers built upon @command{guix
  10461. refresh} (@pxref{Package Transformation Options,
  10462. @option{--with-latest}}). By default, @command{guix refresh} reports
  10463. any packages provided by the distribution that are outdated compared to
  10464. the latest upstream version, like this:
  10465. @example
  10466. $ guix refresh
  10467. gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
  10468. gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
  10469. @end example
  10470. Alternatively, one can specify packages to consider, in which case a
  10471. warning is emitted for packages that lack an updater:
  10472. @example
  10473. $ guix refresh coreutils guile guile-ssh
  10474. gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
  10475. gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
  10476. @end example
  10477. @command{guix refresh} browses the upstream repository of each package and determines
  10478. the highest version number of the releases therein. The command
  10479. knows how to update specific types of packages: GNU packages, ELPA
  10480. packages, etc.---see the documentation for @option{--type} below. There
  10481. are many packages, though, for which it lacks a method to determine
  10482. whether a new upstream release is available. However, the mechanism is
  10483. extensible, so feel free to get in touch with us to add a new method!
  10484. @table @code
  10485. @item --recursive
  10486. Consider the packages specified, and all the packages upon which they depend.
  10487. @example
  10488. $ guix refresh --recursive coreutils
  10489. gnu/packages/acl.scm:40:13: acl would be upgraded from 2.2.53 to 2.3.1
  10490. gnu/packages/m4.scm:30:12: 1.4.18 is already the latest version of m4
  10491. gnu/packages/xml.scm:68:2: warning: no updater for expat
  10492. gnu/packages/multiprecision.scm:40:12: 6.1.2 is already the latest version of gmp
  10493. @dots{}
  10494. @end example
  10495. @end table
  10496. Sometimes the upstream name differs from the package name used in Guix,
  10497. and @command{guix refresh} needs a little help. Most updaters honor the
  10498. @code{upstream-name} property in package definitions, which can be used
  10499. to that effect:
  10500. @lisp
  10501. (define-public network-manager
  10502. (package
  10503. (name "network-manager")
  10504. ;; @dots{}
  10505. (properties '((upstream-name . "NetworkManager")))))
  10506. @end lisp
  10507. When passed @option{--update}, it modifies distribution source files to
  10508. update the version numbers and source tarball hashes of those package
  10509. recipes (@pxref{Defining Packages}). This is achieved by downloading
  10510. each package's latest source tarball and its associated OpenPGP
  10511. signature, authenticating the downloaded tarball against its signature
  10512. using @command{gpgv}, and finally computing its hash---note that GnuPG must be
  10513. installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
  10514. When the public
  10515. key used to sign the tarball is missing from the user's keyring, an
  10516. attempt is made to automatically retrieve it from a public key server;
  10517. when this is successful, the key is added to the user's keyring; otherwise,
  10518. @command{guix refresh} reports an error.
  10519. The following options are supported:
  10520. @table @code
  10521. @item --expression=@var{expr}
  10522. @itemx -e @var{expr}
  10523. Consider the package @var{expr} evaluates to.
  10524. This is useful to precisely refer to a package, as in this example:
  10525. @example
  10526. guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
  10527. @end example
  10528. This command lists the dependents of the ``final'' libc (essentially all
  10529. the packages).
  10530. @item --update
  10531. @itemx -u
  10532. Update distribution source files (package recipes) in place. This is
  10533. usually run from a checkout of the Guix source tree (@pxref{Running
  10534. Guix Before It Is Installed}):
  10535. @example
  10536. $ ./pre-inst-env guix refresh -s non-core -u
  10537. @end example
  10538. @xref{Defining Packages}, for more information on package definitions.
  10539. @item --select=[@var{subset}]
  10540. @itemx -s @var{subset}
  10541. Select all the packages in @var{subset}, one of @code{core} or
  10542. @code{non-core}.
  10543. The @code{core} subset refers to all the packages at the core of the
  10544. distribution---i.e., packages that are used to build ``everything
  10545. else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
  10546. changing one of these packages in the distribution entails a rebuild of
  10547. all the others. Thus, such updates are an inconvenience to users in
  10548. terms of build time or bandwidth used to achieve the upgrade.
  10549. The @code{non-core} subset refers to the remaining packages. It is
  10550. typically useful in cases where an update of the core packages would be
  10551. inconvenient.
  10552. @item --manifest=@var{file}
  10553. @itemx -m @var{file}
  10554. Select all the packages from the manifest in @var{file}. This is useful to
  10555. check if any packages of the user manifest can be updated.
  10556. @item --type=@var{updater}
  10557. @itemx -t @var{updater}
  10558. Select only packages handled by @var{updater} (may be a comma-separated
  10559. list of updaters). Currently, @var{updater} may be one of:
  10560. @table @code
  10561. @item gnu
  10562. the updater for GNU packages;
  10563. @item savannah
  10564. the updater for packages hosted at @uref{https://savannah.gnu.org, Savannah};
  10565. @item sourceforge
  10566. the updater for packages hosted at @uref{https://sourceforge.net, SourceForge};
  10567. @item gnome
  10568. the updater for GNOME packages;
  10569. @item kde
  10570. the updater for KDE packages;
  10571. @item xorg
  10572. the updater for X.org packages;
  10573. @item kernel.org
  10574. the updater for packages hosted on kernel.org;
  10575. @item egg
  10576. the updater for @uref{https://wiki.call-cc.org/eggs/, Egg} packages;
  10577. @item elpa
  10578. the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
  10579. @item cran
  10580. the updater for @uref{https://cran.r-project.org/, CRAN} packages;
  10581. @item bioconductor
  10582. the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
  10583. @item cpan
  10584. the updater for @uref{https://www.cpan.org/, CPAN} packages;
  10585. @item pypi
  10586. the updater for @uref{https://pypi.python.org, PyPI} packages.
  10587. @item gem
  10588. the updater for @uref{https://rubygems.org, RubyGems} packages.
  10589. @item github
  10590. the updater for @uref{https://github.com, GitHub} packages.
  10591. @item hackage
  10592. the updater for @uref{https://hackage.haskell.org, Hackage} packages.
  10593. @item stackage
  10594. the updater for @uref{https://www.stackage.org, Stackage} packages.
  10595. @item crate
  10596. the updater for @uref{https://crates.io, Crates} packages.
  10597. @item launchpad
  10598. the updater for @uref{https://launchpad.net, Launchpad} packages.
  10599. @item generic-html
  10600. a generic updater that crawls the HTML page where the source tarball of
  10601. the package is hosted, when applicable.
  10602. @item generic-git
  10603. a generic updater for packages hosted on Git repositories. It tries to
  10604. be smart about parsing Git tag names, but if it is not able to parse the
  10605. tag name and compare tags correctly, users can define the following
  10606. properties for a package.
  10607. @itemize
  10608. @item @code{release-tag-prefix}: a regular expression for matching a prefix of
  10609. the tag name.
  10610. @item @code{release-tag-suffix}: a regular expression for matching a suffix of
  10611. the tag name.
  10612. @item @code{release-tag-version-delimiter}: a string used as the delimiter in
  10613. the tag name for separating the numbers of the version.
  10614. @item @code{accept-pre-releases}: by default, the updater will ignore
  10615. pre-releases; to make it also look for pre-releases, set the this
  10616. property to @code{#t}.
  10617. @end itemize
  10618. @lisp
  10619. (package
  10620. (name "foo")
  10621. ;; ...
  10622. (properties
  10623. '((release-tag-prefix . "^release0-")
  10624. (release-tag-suffix . "[a-z]?$")
  10625. (release-tag-version-delimiter . ":"))))
  10626. @end lisp
  10627. @end table
  10628. For instance, the following command only checks for updates of Emacs
  10629. packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
  10630. @example
  10631. $ guix refresh --type=elpa,cran
  10632. gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
  10633. gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
  10634. @end example
  10635. @item --list-updaters
  10636. @itemx -L
  10637. List available updaters and exit (see @option{--type} above).
  10638. For each updater, display the fraction of packages it covers; at the
  10639. end, display the fraction of packages covered by all these updaters.
  10640. @end table
  10641. In addition, @command{guix refresh} can be passed one or more package
  10642. names, as in this example:
  10643. @example
  10644. $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
  10645. @end example
  10646. @noindent
  10647. The command above specifically updates the @code{emacs} and
  10648. @code{idutils} packages. The @option{--select} option would have no
  10649. effect in this case. You might also want to update definitions that
  10650. correspond to the packages installed in your profile:
  10651. @example
  10652. $ ./pre-inst-env guix refresh -u \
  10653. $(guix package --list-installed | cut -f1)
  10654. @end example
  10655. When considering whether to upgrade a package, it is sometimes
  10656. convenient to know which packages would be affected by the upgrade and
  10657. should be checked for compatibility. For this the following option may
  10658. be used when passing @command{guix refresh} one or more package names:
  10659. @table @code
  10660. @item --list-dependent
  10661. @itemx -l
  10662. List top-level dependent packages that would need to be rebuilt as a
  10663. result of upgrading one or more packages.
  10664. @xref{Invoking guix graph, the @code{reverse-package} type of
  10665. @command{guix graph}}, for information on how to visualize the list of
  10666. dependents of a package.
  10667. @end table
  10668. Be aware that the @option{--list-dependent} option only
  10669. @emph{approximates} the rebuilds that would be required as a result of
  10670. an upgrade. More rebuilds might be required under some circumstances.
  10671. @example
  10672. $ guix refresh --list-dependent flex
  10673. Building the following 120 packages would ensure 213 dependent packages are rebuilt:
  10674. hop@@2.4.0 emacs-geiser@@0.13 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
  10675. @end example
  10676. The command above lists a set of packages that could be built to check
  10677. for compatibility with an upgraded @code{flex} package.
  10678. @table @code
  10679. @item --list-transitive
  10680. List all the packages which one or more packages depend upon.
  10681. @example
  10682. $ guix refresh --list-transitive flex
  10683. flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
  10684. bison@@3.0.5 indent@@2.2.10 tar@@1.30 gzip@@1.9 bzip2@@1.0.6 xz@@5.2.4 file@@5.33 @dots{}
  10685. @end example
  10686. @end table
  10687. The command above lists a set of packages which, when changed, would cause
  10688. @code{flex} to be rebuilt.
  10689. The following options can be used to customize GnuPG operation:
  10690. @table @code
  10691. @item --gpg=@var{command}
  10692. Use @var{command} as the GnuPG 2.x command. @var{command} is searched
  10693. for in @code{$PATH}.
  10694. @item --keyring=@var{file}
  10695. Use @var{file} as the keyring for upstream keys. @var{file} must be in the
  10696. @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
  10697. and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
  10698. (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
  10699. information on a tool to manipulate keybox files).
  10700. When this option is omitted, @command{guix refresh} uses
  10701. @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
  10702. signing keys. OpenPGP signatures are checked against keys from this keyring;
  10703. missing keys are downloaded to this keyring as well (see
  10704. @option{--key-download} below).
  10705. You can export keys from your default GPG keyring into a keybox file using
  10706. commands like this one:
  10707. @example
  10708. gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
  10709. @end example
  10710. Likewise, you can fetch keys to a specific keybox file like this:
  10711. @example
  10712. gpg --no-default-keyring --keyring mykeyring.kbx \
  10713. --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
  10714. @end example
  10715. @xref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
  10716. Privacy Guard}, for more information on GPG's @option{--keyring} option.
  10717. @item --key-download=@var{policy}
  10718. Handle missing OpenPGP keys according to @var{policy}, which may be one
  10719. of:
  10720. @table @code
  10721. @item always
  10722. Always download missing OpenPGP keys from the key server, and add them
  10723. to the user's GnuPG keyring.
  10724. @item never
  10725. Never try to download missing OpenPGP keys. Instead just bail out.
  10726. @item interactive
  10727. When a package signed with an unknown OpenPGP key is encountered, ask
  10728. the user whether to download it or not. This is the default behavior.
  10729. @end table
  10730. @item --key-server=@var{host}
  10731. Use @var{host} as the OpenPGP key server when importing a public key.
  10732. @item --load-path=@var{directory}
  10733. Add @var{directory} to the front of the package module search path
  10734. (@pxref{Package Modules}).
  10735. This allows users to define their own packages and make them visible to
  10736. the command-line tools.
  10737. @end table
  10738. The @code{github} updater uses the
  10739. @uref{https://developer.github.com/v3/, GitHub API} to query for new
  10740. releases. When used repeatedly e.g.@: when refreshing all packages,
  10741. GitHub will eventually refuse to answer any further API requests. By
  10742. default 60 API requests per hour are allowed, and a full refresh on all
  10743. GitHub packages in Guix requires more than this. Authentication with
  10744. GitHub through the use of an API token alleviates these limits. To use
  10745. an API token, set the environment variable @env{GUIX_GITHUB_TOKEN} to a
  10746. token procured from @uref{https://github.com/settings/tokens} or
  10747. otherwise.
  10748. @node Invoking guix style
  10749. @section Invoking @command{guix style}
  10750. The @command{guix style} command helps packagers style their package
  10751. definitions according to the latest fashionable trends. The command
  10752. currently provides the following styling rules:
  10753. @itemize
  10754. @item
  10755. formatting package definitions according to the project's conventions
  10756. (@pxref{Formatting Code});
  10757. @item
  10758. rewriting package inputs to the ``new style'', as explained below.
  10759. @end itemize
  10760. The way package inputs are written is going through a transition
  10761. (@pxref{package Reference}, for more on package inputs). Until version
  10762. 1.3.0, package inputs were written using the ``old style'', where each
  10763. input was given an explicit label, most of the time the package name:
  10764. @lisp
  10765. (package
  10766. ;; @dots{}
  10767. ;; The "old style" (deprecated).
  10768. (inputs `(("libunistring" ,libunistring)
  10769. ("libffi" ,libffi))))
  10770. @end lisp
  10771. Today, the old style is deprecated and the preferred style looks like
  10772. this:
  10773. @lisp
  10774. (package
  10775. ;; @dots{}
  10776. ;; The "new style".
  10777. (inputs (list libunistring libffi)))
  10778. @end lisp
  10779. Likewise, uses of @code{alist-delete} and friends to manipulate inputs
  10780. is now deprecated in favor of @code{modify-inputs} (@pxref{Defining
  10781. Package Variants}, for more info on @code{modify-inputs}).
  10782. In the vast majority of cases, this is a purely mechanical change on the
  10783. surface syntax that does not even incur a package rebuild. Running
  10784. @command{guix style -S inputs} can do that for you, whether you're working on
  10785. packages in Guix proper or in an external channel.
  10786. The general syntax is:
  10787. @example
  10788. guix style [@var{options}] @var{package}@dots{}
  10789. @end example
  10790. This causes @command{guix style} to analyze and rewrite the definition
  10791. of @var{package}@dots{} or, when @var{package} is omitted, of @emph{all}
  10792. the packages. The @option{--styling} or @option{-S} option allows you
  10793. to select the style rule, the default rule being @code{format}---see
  10794. below.
  10795. The available options are listed below.
  10796. @table @code
  10797. @item --dry-run
  10798. @itemx -n
  10799. Show source file locations that would be edited but do not modify them.
  10800. @item --styling=@var{rule}
  10801. @itemx -S @var{rule}
  10802. Apply @var{rule}, one of the following styling rules:
  10803. @table @code
  10804. @item format
  10805. Format the given package definition(s)---this is the default styling
  10806. rule. For example, a packager running Guix on a checkout
  10807. (@pxref{Running Guix Before It Is Installed}) might want to reformat the
  10808. definition of the Coreutils package like so:
  10809. @example
  10810. ./pre-inst-env guix style coreutils
  10811. @end example
  10812. @item inputs
  10813. Rewrite package inputs to the ``new style'', as described above. This
  10814. is how you would rewrite inputs of package @code{whatnot} in your own
  10815. channel:
  10816. @example
  10817. guix style -L ~/my/channel -S inputs whatnot
  10818. @end example
  10819. Rewriting is done in a conservative way: preserving comments and bailing
  10820. out if it cannot make sense of the code that appears in an inputs field.
  10821. The @option{--input-simplification} option described below provides
  10822. fine-grain control over when inputs should be simplified.
  10823. @end table
  10824. @item --load-path=@var{directory}
  10825. @itemx -L @var{directory}
  10826. Add @var{directory} to the front of the package module search path
  10827. (@pxref{Package Modules}).
  10828. @item --expression=@var{expr}
  10829. @itemx -e @var{expr}
  10830. Style the package @var{expr} evaluates to.
  10831. For example, running:
  10832. @example
  10833. guix style -e '(@@ (gnu packages gcc) gcc-5)'
  10834. @end example
  10835. styles the @code{gcc-5} package definition.
  10836. @item --input-simplification=@var{policy}
  10837. When using the @code{inputs} styling rule, with @samp{-S inputs}, this
  10838. option specifies the package input simplification policy for cases where
  10839. an input label does not match the corresponding package name.
  10840. @var{policy} may be one of the following:
  10841. @table @code
  10842. @item silent
  10843. Simplify inputs only when the change is ``silent'', meaning that the
  10844. package does not need to be rebuilt (its derivation is unchanged).
  10845. @item safe
  10846. Simplify inputs only when that is ``safe'' to do: the package might need
  10847. to be rebuilt, but the change is known to have no observable effect.
  10848. @item always
  10849. Simplify inputs even when input labels do not match package names, and
  10850. even if that might have an observable effect.
  10851. @end table
  10852. The default is @code{silent}, meaning that input simplifications do not
  10853. trigger any package rebuild.
  10854. @end table
  10855. @node Invoking guix lint
  10856. @section Invoking @command{guix lint}
  10857. @cindex @command{guix lint}
  10858. @cindex package, checking for errors
  10859. The @command{guix lint} command is meant to help package developers avoid
  10860. common errors and use a consistent style. It runs a number of checks on
  10861. a given set of packages in order to find common mistakes in their
  10862. definitions. Available @dfn{checkers} include (see
  10863. @option{--list-checkers} for a complete list):
  10864. @table @code
  10865. @item synopsis
  10866. @itemx description
  10867. Validate certain typographical and stylistic rules about package
  10868. descriptions and synopses.
  10869. @item inputs-should-be-native
  10870. Identify inputs that should most likely be native inputs.
  10871. @item source
  10872. @itemx home-page
  10873. @itemx mirror-url
  10874. @itemx github-url
  10875. @itemx source-file-name
  10876. Probe @code{home-page} and @code{source} URLs and report those that are
  10877. invalid. Suggest a @code{mirror://} URL when applicable. If the
  10878. @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
  10879. URL@. Check that the source file name is meaningful, e.g.@: is not just a
  10880. version number or ``git-checkout'', without a declared @code{file-name}
  10881. (@pxref{origin Reference}).
  10882. @item source-unstable-tarball
  10883. Parse the @code{source} URL to determine if a tarball from GitHub is
  10884. autogenerated or if it is a release tarball. Unfortunately GitHub's
  10885. autogenerated tarballs are sometimes regenerated.
  10886. @item derivation
  10887. Check that the derivation of the given packages can be successfully
  10888. computed for all the supported systems (@pxref{Derivations}).
  10889. @item profile-collisions
  10890. Check whether installing the given packages in a profile would lead to
  10891. collisions. Collisions occur when several packages with the same name
  10892. but a different version or a different store file name are propagated.
  10893. @xref{package Reference, @code{propagated-inputs}}, for more information
  10894. on propagated inputs.
  10895. @item archival
  10896. @cindex Software Heritage, source code archive
  10897. @cindex archival of source code, Software Heritage
  10898. Checks whether the package's source code is archived at
  10899. @uref{https://www.softwareheritage.org, Software Heritage}.
  10900. When the source code that is not archived comes from a version-control system
  10901. (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
  10902. ``save'' request so that it eventually archives it. This ensures that the
  10903. source will remain available in the long term, and that Guix can fall back to
  10904. Software Heritage should the source code disappear from its original host.
  10905. The status of recent ``save'' requests can be
  10906. @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
  10907. When source code is a tarball obtained with @code{url-fetch}, simply print a
  10908. message when it is not archived. As of this writing, Software Heritage does
  10909. not allow requests to save arbitrary tarballs; we are working on ways to
  10910. ensure that non-VCS source code is also archived.
  10911. Software Heritage
  10912. @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
  10913. request rate per IP address}. When the limit is reached, @command{guix lint}
  10914. prints a message and the @code{archival} checker stops doing anything until
  10915. that limit has been reset.
  10916. @item cve
  10917. @cindex security vulnerabilities
  10918. @cindex CVE, Common Vulnerabilities and Exposures
  10919. Report known vulnerabilities found in the Common Vulnerabilities and
  10920. Exposures (CVE) databases of the current and past year
  10921. @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
  10922. NIST}.
  10923. To view information about a particular vulnerability, visit pages such as:
  10924. @itemize
  10925. @item
  10926. @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
  10927. @item
  10928. @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
  10929. @end itemize
  10930. @noindent
  10931. where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
  10932. @code{CVE-2015-7554}.
  10933. Package developers can specify in package recipes the
  10934. @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
  10935. name and version of the package when they differ from the name or version
  10936. that Guix uses, as in this example:
  10937. @lisp
  10938. (package
  10939. (name "grub")
  10940. ;; @dots{}
  10941. ;; CPE calls this package "grub2".
  10942. (properties '((cpe-name . "grub2")
  10943. (cpe-version . "2.3"))))
  10944. @end lisp
  10945. @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
  10946. Some entries in the CVE database do not specify which version of a
  10947. package they apply to, and would thus ``stick around'' forever. Package
  10948. developers who found CVE alerts and verified they can be ignored can
  10949. declare them as in this example:
  10950. @lisp
  10951. (package
  10952. (name "t1lib")
  10953. ;; @dots{}
  10954. ;; These CVEs no longer apply and can be safely ignored.
  10955. (properties `((lint-hidden-cve . ("CVE-2011-0433"
  10956. "CVE-2011-1553"
  10957. "CVE-2011-1554"
  10958. "CVE-2011-5244")))))
  10959. @end lisp
  10960. @item formatting
  10961. Warn about obvious source code formatting issues: trailing white space,
  10962. use of tabulations, etc.
  10963. @item input-labels
  10964. Report old-style input labels that do not match the name of the
  10965. corresponding package. This aims to help migrate from the ``old input
  10966. style''. @xref{package Reference}, for more information on package
  10967. inputs and input styles. @xref{Invoking guix style}, on how to migrate
  10968. to the new style.
  10969. @end table
  10970. The general syntax is:
  10971. @example
  10972. guix lint @var{options} @var{package}@dots{}
  10973. @end example
  10974. If no package is given on the command line, then all packages are checked.
  10975. The @var{options} may be zero or more of the following:
  10976. @table @code
  10977. @item --list-checkers
  10978. @itemx -l
  10979. List and describe all the available checkers that will be run on packages
  10980. and exit.
  10981. @item --checkers
  10982. @itemx -c
  10983. Only enable the checkers specified in a comma-separated list using the
  10984. names returned by @option{--list-checkers}.
  10985. @item --exclude
  10986. @itemx -x
  10987. Only disable the checkers specified in a comma-separated list using the
  10988. names returned by @option{--list-checkers}.
  10989. @item --no-network
  10990. @itemx -n
  10991. Only enable the checkers that do not depend on Internet access.
  10992. @item --load-path=@var{directory}
  10993. @itemx -L @var{directory}
  10994. Add @var{directory} to the front of the package module search path
  10995. (@pxref{Package Modules}).
  10996. This allows users to define their own packages and make them visible to
  10997. the command-line tools.
  10998. @end table
  10999. @node Invoking guix size
  11000. @section Invoking @command{guix size}
  11001. @cindex size
  11002. @cindex package size
  11003. @cindex closure
  11004. @cindex @command{guix size}
  11005. The @command{guix size} command helps package developers profile the
  11006. disk usage of packages. It is easy to overlook the impact of an
  11007. additional dependency added to a package, or the impact of using a
  11008. single output for a package that could easily be split (@pxref{Packages
  11009. with Multiple Outputs}). Such are the typical issues that
  11010. @command{guix size} can highlight.
  11011. The command can be passed one or more package specifications
  11012. such as @code{gcc@@4.8}
  11013. or @code{guile:debug}, or a file name in the store. Consider this
  11014. example:
  11015. @example
  11016. $ guix size coreutils
  11017. store item total self
  11018. /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
  11019. /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
  11020. /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
  11021. /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
  11022. /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
  11023. /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
  11024. /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
  11025. /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
  11026. total: 78.9 MiB
  11027. @end example
  11028. @cindex closure
  11029. The store items listed here constitute the @dfn{transitive closure} of
  11030. Coreutils---i.e., Coreutils and all its dependencies, recursively---as
  11031. would be returned by:
  11032. @example
  11033. $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
  11034. @end example
  11035. Here the output shows three columns next to store items. The first column,
  11036. labeled ``total'', shows the size in mebibytes (MiB) of the closure of
  11037. the store item---that is, its own size plus the size of all its
  11038. dependencies. The next column, labeled ``self'', shows the size of the
  11039. item itself. The last column shows the ratio of the size of the item
  11040. itself to the space occupied by all the items listed here.
  11041. In this example, we see that the closure of Coreutils weighs in at
  11042. 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
  11043. libraries. (That libc and GCC's libraries represent a large fraction of
  11044. the closure is not a problem @i{per se} because they are always available
  11045. on the system anyway.)
  11046. Since the command also accepts store file names, assessing the size of
  11047. a build result is straightforward:
  11048. @example
  11049. guix size $(guix system build config.scm)
  11050. @end example
  11051. When the package(s) passed to @command{guix size} are available in the
  11052. store@footnote{More precisely, @command{guix size} looks for the
  11053. @emph{ungrafted} variant of the given package(s), as returned by
  11054. @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
  11055. for information on grafts.}, @command{guix size} queries the daemon to determine its
  11056. dependencies, and measures its size in the store, similar to @command{du
  11057. -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
  11058. Coreutils}).
  11059. When the given packages are @emph{not} in the store, @command{guix size}
  11060. reports information based on the available substitutes
  11061. (@pxref{Substitutes}). This makes it possible it to profile disk usage of
  11062. store items that are not even on disk, only available remotely.
  11063. You can also specify several package names:
  11064. @example
  11065. $ guix size coreutils grep sed bash
  11066. store item total self
  11067. /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
  11068. /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
  11069. /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
  11070. /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
  11071. @dots{}
  11072. total: 102.3 MiB
  11073. @end example
  11074. @noindent
  11075. In this example we see that the combination of the four packages takes
  11076. 102.3@tie{}MiB in total, which is much less than the sum of each closure
  11077. since they have a lot of dependencies in common.
  11078. When looking at the profile returned by @command{guix size}, you may
  11079. find yourself wondering why a given package shows up in the profile at
  11080. all. To understand it, you can use @command{guix graph --path -t
  11081. references} to display the shortest path between the two packages
  11082. (@pxref{Invoking guix graph}).
  11083. The available options are:
  11084. @table @option
  11085. @item --substitute-urls=@var{urls}
  11086. Use substitute information from @var{urls}.
  11087. @xref{client-substitute-urls, the same option for @code{guix build}}.
  11088. @item --sort=@var{key}
  11089. Sort lines according to @var{key}, one of the following options:
  11090. @table @code
  11091. @item self
  11092. the size of each item (the default);
  11093. @item closure
  11094. the total size of the item's closure.
  11095. @end table
  11096. @item --map-file=@var{file}
  11097. Write a graphical map of disk usage in PNG format to @var{file}.
  11098. For the example above, the map looks like this:
  11099. @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
  11100. produced by @command{guix size}}
  11101. This option requires that
  11102. @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
  11103. installed and visible in Guile's module search path. When that is not
  11104. the case, @command{guix size} fails as it tries to load it.
  11105. @item --system=@var{system}
  11106. @itemx -s @var{system}
  11107. Consider packages for @var{system}---e.g., @code{x86_64-linux}.
  11108. @item --load-path=@var{directory}
  11109. @itemx -L @var{directory}
  11110. Add @var{directory} to the front of the package module search path
  11111. (@pxref{Package Modules}).
  11112. This allows users to define their own packages and make them visible to
  11113. the command-line tools.
  11114. @end table
  11115. @node Invoking guix graph
  11116. @section Invoking @command{guix graph}
  11117. @cindex DAG
  11118. @cindex @command{guix graph}
  11119. @cindex package dependencies
  11120. Packages and their dependencies form a @dfn{graph}, specifically a
  11121. directed acyclic graph (DAG). It can quickly become difficult to have a
  11122. mental model of the package DAG, so the @command{guix graph} command
  11123. provides a visual representation of the DAG@. By default,
  11124. @command{guix graph} emits a DAG representation in the input format of
  11125. @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
  11126. directly to the @command{dot} command of Graphviz. It can also emit an
  11127. HTML page with embedded JavaScript code to display a ``chord diagram''
  11128. in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
  11129. emit Cypher queries to construct a graph in a graph database supporting
  11130. the @uref{https://www.opencypher.org/, openCypher} query language. With
  11131. @option{--path}, it simply displays the shortest path between two
  11132. packages. The general syntax is:
  11133. @example
  11134. guix graph @var{options} @var{package}@dots{}
  11135. @end example
  11136. For example, the following command generates a PDF file representing the
  11137. package DAG for the GNU@tie{}Core Utilities, showing its build-time
  11138. dependencies:
  11139. @example
  11140. guix graph coreutils | dot -Tpdf > dag.pdf
  11141. @end example
  11142. The output looks like this:
  11143. @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
  11144. Nice little graph, no?
  11145. You may find it more pleasant to navigate the graph interactively with
  11146. @command{xdot} (from the @code{xdot} package):
  11147. @example
  11148. guix graph coreutils | xdot -
  11149. @end example
  11150. But there is more than one graph! The one above is concise: it is the
  11151. graph of package objects, omitting implicit inputs such as GCC, libc,
  11152. grep, etc. It is often useful to have such a concise graph, but
  11153. sometimes one may want to see more details. @command{guix graph} supports
  11154. several types of graphs, allowing you to choose the level of detail:
  11155. @table @code
  11156. @item package
  11157. This is the default type used in the example above. It shows the DAG of
  11158. package objects, excluding implicit dependencies. It is concise, but
  11159. filters out many details.
  11160. @item reverse-package
  11161. This shows the @emph{reverse} DAG of packages. For example:
  11162. @example
  11163. guix graph --type=reverse-package ocaml
  11164. @end example
  11165. ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
  11166. you are also interested in cases where OCaml is an implicit dependency, see
  11167. @code{reverse-bag} below).
  11168. Note that for core packages this can yield huge graphs. If all you want
  11169. is to know the number of packages that depend on a given package, use
  11170. @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
  11171. @option{--list-dependent}}).
  11172. @item bag-emerged
  11173. This is the package DAG, @emph{including} implicit inputs.
  11174. For instance, the following command:
  11175. @example
  11176. guix graph --type=bag-emerged coreutils
  11177. @end example
  11178. ...@: yields this bigger graph:
  11179. @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
  11180. At the bottom of the graph, we see all the implicit inputs of
  11181. @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
  11182. Now, note that the dependencies of these implicit inputs---that is, the
  11183. @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
  11184. here, for conciseness.
  11185. @item bag
  11186. Similar to @code{bag-emerged}, but this time including all the bootstrap
  11187. dependencies.
  11188. @item bag-with-origins
  11189. Similar to @code{bag}, but also showing origins and their dependencies.
  11190. @item reverse-bag
  11191. This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
  11192. it also takes implicit dependencies into account. For example:
  11193. @example
  11194. guix graph -t reverse-bag dune
  11195. @end example
  11196. @noindent
  11197. ...@: yields the graph of all packages that depend on Dune, directly or
  11198. indirectly. Since Dune is an @emph{implicit} dependency of many packages
  11199. @i{via} @code{dune-build-system}, this shows a large number of packages,
  11200. whereas @code{reverse-package} would show very few if any.
  11201. @item derivation
  11202. This is the most detailed representation: It shows the DAG of
  11203. derivations (@pxref{Derivations}) and plain store items. Compared to
  11204. the above representation, many additional nodes are visible, including
  11205. build scripts, patches, Guile modules, etc.
  11206. For this type of graph, it is also possible to pass a @file{.drv} file
  11207. name instead of a package name, as in:
  11208. @example
  11209. guix graph -t derivation $(guix system build -d my-config.scm)
  11210. @end example
  11211. @item module
  11212. This is the graph of @dfn{package modules} (@pxref{Package Modules}).
  11213. For example, the following command shows the graph for the package
  11214. module that defines the @code{guile} package:
  11215. @example
  11216. guix graph -t module guile | xdot -
  11217. @end example
  11218. @end table
  11219. All the types above correspond to @emph{build-time dependencies}. The
  11220. following graph type represents the @emph{run-time dependencies}:
  11221. @table @code
  11222. @item references
  11223. This is the graph of @dfn{references} of a package output, as returned
  11224. by @command{guix gc --references} (@pxref{Invoking guix gc}).
  11225. If the given package output is not available in the store, @command{guix
  11226. graph} attempts to obtain dependency information from substitutes.
  11227. Here you can also pass a store file name instead of a package name. For
  11228. example, the command below produces the reference graph of your profile
  11229. (which can be big!):
  11230. @example
  11231. guix graph -t references $(readlink -f ~/.guix-profile)
  11232. @end example
  11233. @item referrers
  11234. This is the graph of the @dfn{referrers} of a store item, as returned by
  11235. @command{guix gc --referrers} (@pxref{Invoking guix gc}).
  11236. This relies exclusively on local information from your store. For
  11237. instance, let us suppose that the current Inkscape is available in 10
  11238. profiles on your machine; @command{guix graph -t referrers inkscape}
  11239. will show a graph rooted at Inkscape and with those 10 profiles linked
  11240. to it.
  11241. It can help determine what is preventing a store item from being garbage
  11242. collected.
  11243. @end table
  11244. @cindex shortest path, between packages
  11245. Often, the graph of the package you are interested in does not fit on
  11246. your screen, and anyway all you want to know is @emph{why} that package
  11247. actually depends on some seemingly unrelated package. The
  11248. @option{--path} option instructs @command{guix graph} to display the
  11249. shortest path between two packages (or derivations, or store items,
  11250. etc.):
  11251. @example
  11252. $ guix graph --path emacs libunistring
  11253. emacs@@26.3
  11254. mailutils@@3.9
  11255. libunistring@@0.9.10
  11256. $ guix graph --path -t derivation emacs libunistring
  11257. /gnu/store/@dots{}-emacs-26.3.drv
  11258. /gnu/store/@dots{}-mailutils-3.9.drv
  11259. /gnu/store/@dots{}-libunistring-0.9.10.drv
  11260. $ guix graph --path -t references emacs libunistring
  11261. /gnu/store/@dots{}-emacs-26.3
  11262. /gnu/store/@dots{}-libidn2-2.2.0
  11263. /gnu/store/@dots{}-libunistring-0.9.10
  11264. @end example
  11265. Sometimes you still want to visualize the graph but would like to trim
  11266. it so it can actually be displayed. One way to do it is via the
  11267. @option{--max-depth} (or @option{-M}) option, which lets you specify the
  11268. maximum depth of the graph. In the example below, we visualize only
  11269. @code{libreoffice} and the nodes whose distance to @code{libreoffice} is
  11270. at most 2:
  11271. @example
  11272. guix graph -M 2 libreoffice | xdot -f fdp -
  11273. @end example
  11274. Mind you, that's still a big ball of spaghetti, but at least
  11275. @command{dot} can render it quickly and it can be browsed somewhat.
  11276. The available options are the following:
  11277. @table @option
  11278. @item --type=@var{type}
  11279. @itemx -t @var{type}
  11280. Produce a graph output of @var{type}, where @var{type} must be one of
  11281. the values listed above.
  11282. @item --list-types
  11283. List the supported graph types.
  11284. @item --backend=@var{backend}
  11285. @itemx -b @var{backend}
  11286. Produce a graph using the selected @var{backend}.
  11287. @item --list-backends
  11288. List the supported graph backends.
  11289. Currently, the available backends are Graphviz and d3.js.
  11290. @item --path
  11291. Display the shortest path between two nodes of the type specified by
  11292. @option{--type}. The example below shows the shortest path between
  11293. @code{libreoffice} and @code{llvm} according to the references of
  11294. @code{libreoffice}:
  11295. @example
  11296. $ guix graph --path -t references libreoffice llvm
  11297. /gnu/store/@dots{}-libreoffice-6.4.2.2
  11298. /gnu/store/@dots{}-libepoxy-1.5.4
  11299. /gnu/store/@dots{}-mesa-19.3.4
  11300. /gnu/store/@dots{}-llvm-9.0.1
  11301. @end example
  11302. @item --expression=@var{expr}
  11303. @itemx -e @var{expr}
  11304. Consider the package @var{expr} evaluates to.
  11305. This is useful to precisely refer to a package, as in this example:
  11306. @example
  11307. guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
  11308. @end example
  11309. @item --system=@var{system}
  11310. @itemx -s @var{system}
  11311. Display the graph for @var{system}---e.g., @code{i686-linux}.
  11312. The package dependency graph is largely architecture-independent, but there
  11313. are some architecture-dependent bits that this option allows you to visualize.
  11314. @item --load-path=@var{directory}
  11315. @itemx -L @var{directory}
  11316. Add @var{directory} to the front of the package module search path
  11317. (@pxref{Package Modules}).
  11318. This allows users to define their own packages and make them visible to
  11319. the command-line tools.
  11320. @end table
  11321. On top of that, @command{guix graph} supports all the usual package
  11322. transformation options (@pxref{Package Transformation Options}). This
  11323. makes it easy to view the effect of a graph-rewriting transformation
  11324. such as @option{--with-input}. For example, the command below outputs
  11325. the graph of @code{git} once @code{openssl} has been replaced by
  11326. @code{libressl} everywhere in the graph:
  11327. @example
  11328. guix graph git --with-input=openssl=libressl
  11329. @end example
  11330. So many possibilities, so much fun!
  11331. @node Invoking guix publish
  11332. @section Invoking @command{guix publish}
  11333. @cindex @command{guix publish}
  11334. The purpose of @command{guix publish} is to enable users to easily share
  11335. their store with others, who can then use it as a substitute server
  11336. (@pxref{Substitutes}).
  11337. When @command{guix publish} runs, it spawns an HTTP server which allows
  11338. anyone with network access to obtain substitutes from it. This means
  11339. that any machine running Guix can also act as if it were a build farm,
  11340. since the HTTP interface is compatible with Cuirass, the software behind
  11341. the @code{@value{SUBSTITUTE-SERVER-1}} build farm.
  11342. For security, each substitute is signed, allowing recipients to check
  11343. their authenticity and integrity (@pxref{Substitutes}). Because
  11344. @command{guix publish} uses the signing key of the system, which is only
  11345. readable by the system administrator, it must be started as root; the
  11346. @option{--user} option makes it drop root privileges early on.
  11347. The signing key pair must be generated before @command{guix publish} is
  11348. launched, using @command{guix archive --generate-key} (@pxref{Invoking
  11349. guix archive}).
  11350. When the @option{--advertise} option is passed, the server advertises
  11351. its availability on the local network using multicast DNS (mDNS) and DNS
  11352. service discovery (DNS-SD), currently @i{via} Guile-Avahi (@pxref{Top,,,
  11353. guile-avahi, Using Avahi in Guile Scheme Programs}).
  11354. The general syntax is:
  11355. @example
  11356. guix publish @var{options}@dots{}
  11357. @end example
  11358. Running @command{guix publish} without any additional arguments will
  11359. spawn an HTTP server on port 8080:
  11360. @example
  11361. guix publish
  11362. @end example
  11363. Once a publishing server has been authorized, the daemon may download
  11364. substitutes from it. @xref{Getting Substitutes from Other Servers}.
  11365. By default, @command{guix publish} compresses archives on the fly as it
  11366. serves them. This ``on-the-fly'' mode is convenient in that it requires
  11367. no setup and is immediately available. However, when serving lots of
  11368. clients, we recommend using the @option{--cache} option, which enables
  11369. caching of the archives before they are sent to clients---see below for
  11370. details. The @command{guix weather} command provides a handy way to
  11371. check what a server provides (@pxref{Invoking guix weather}).
  11372. As a bonus, @command{guix publish} also serves as a content-addressed
  11373. mirror for source files referenced in @code{origin} records
  11374. (@pxref{origin Reference}). For instance, assuming @command{guix
  11375. publish} is running on @code{example.org}, the following URL returns the
  11376. raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
  11377. (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
  11378. @example
  11379. http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
  11380. @end example
  11381. Obviously, these URLs only work for files that are in the store; in
  11382. other cases, they return 404 (``Not Found'').
  11383. @cindex build logs, publication
  11384. Build logs are available from @code{/log} URLs like:
  11385. @example
  11386. http://example.org/log/gwspk@dots{}-guile-2.2.3
  11387. @end example
  11388. @noindent
  11389. When @command{guix-daemon} is configured to save compressed build logs,
  11390. as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
  11391. URLs return the compressed log as-is, with an appropriate
  11392. @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
  11393. running @command{guix-daemon} with @option{--log-compression=gzip} since
  11394. Web browsers can automatically decompress it, which is not the case with
  11395. Bzip2 compression.
  11396. The following options are available:
  11397. @table @code
  11398. @item --port=@var{port}
  11399. @itemx -p @var{port}
  11400. Listen for HTTP requests on @var{port}.
  11401. @item --listen=@var{host}
  11402. Listen on the network interface for @var{host}. The default is to
  11403. accept connections from any interface.
  11404. @item --user=@var{user}
  11405. @itemx -u @var{user}
  11406. Change privileges to @var{user} as soon as possible---i.e., once the
  11407. server socket is open and the signing key has been read.
  11408. @item --compression[=@var{method}[:@var{level}]]
  11409. @itemx -C [@var{method}[:@var{level}]]
  11410. Compress data using the given @var{method} and @var{level}. @var{method} is
  11411. one of @code{lzip}, @code{zstd}, and @code{gzip}; when @var{method} is
  11412. omitted, @code{gzip} is used.
  11413. When @var{level} is zero, disable compression. The range 1 to 9 corresponds
  11414. to different compression levels: 1 is the fastest, and 9 is the best
  11415. (CPU-intensive). The default is 3.
  11416. Usually, @code{lzip} compresses noticeably better than @code{gzip} for a
  11417. small increase in CPU usage; see
  11418. @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip
  11419. Web page}. However, @code{lzip} achieves low decompression throughput
  11420. (on the order of 50@tie{}MiB/s on modern hardware), which can be a
  11421. bottleneck for someone who downloads over a fast network connection.
  11422. The compression ratio of @code{zstd} is between that of @code{lzip} and
  11423. that of @code{gzip}; its main advantage is a
  11424. @uref{https://facebook.github.io/zstd/,high decompression speed}.
  11425. Unless @option{--cache} is used, compression occurs on the fly and
  11426. the compressed streams are not
  11427. cached. Thus, to reduce load on the machine that runs @command{guix
  11428. publish}, it may be a good idea to choose a low compression level, to
  11429. run @command{guix publish} behind a caching proxy, or to use
  11430. @option{--cache}. Using @option{--cache} has the advantage that it
  11431. allows @command{guix publish} to add @code{Content-Length} HTTP header
  11432. to its responses.
  11433. This option can be repeated, in which case every substitute gets compressed
  11434. using all the selected methods, and all of them are advertised. This is
  11435. useful when users may not support all the compression methods: they can select
  11436. the one they support.
  11437. @item --cache=@var{directory}
  11438. @itemx -c @var{directory}
  11439. Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
  11440. and only serve archives that are in cache.
  11441. When this option is omitted, archives and meta-data are created
  11442. on-the-fly. This can reduce the available bandwidth, especially when
  11443. compression is enabled, since this may become CPU-bound. Another
  11444. drawback of the default mode is that the length of archives is not known
  11445. in advance, so @command{guix publish} does not add a
  11446. @code{Content-Length} HTTP header to its responses, which in turn
  11447. prevents clients from knowing the amount of data being downloaded.
  11448. Conversely, when @option{--cache} is used, the first request for a store
  11449. item (@i{via} a @code{.narinfo} URL) triggers a
  11450. background process to @dfn{bake} the archive---computing its
  11451. @code{.narinfo} and compressing the archive, if needed. Once the
  11452. archive is cached in @var{directory}, subsequent requests succeed and
  11453. are served directly from the cache, which guarantees that clients get
  11454. the best possible bandwidth.
  11455. That first @code{.narinfo} request nonetheless returns 200, provided the
  11456. requested store item is ``small enough'', below the cache bypass
  11457. threshold---see @option{--cache-bypass-threshold} below. That way,
  11458. clients do not have to wait until the archive is baked. For larger
  11459. store items, the first @code{.narinfo} request returns 404, meaning that
  11460. clients have to wait until the archive is baked.
  11461. The ``baking'' process is performed by worker threads. By default, one
  11462. thread per CPU core is created, but this can be customized. See
  11463. @option{--workers} below.
  11464. When @option{--ttl} is used, cached entries are automatically deleted
  11465. when they have expired.
  11466. @item --workers=@var{N}
  11467. When @option{--cache} is used, request the allocation of @var{N} worker
  11468. threads to ``bake'' archives.
  11469. @item --ttl=@var{ttl}
  11470. Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
  11471. (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
  11472. days, @code{1m} means 1 month, and so on.
  11473. This allows the user's Guix to keep substitute information in cache for
  11474. @var{ttl}. However, note that @code{guix publish} does not itself
  11475. guarantee that the store items it provides will indeed remain available
  11476. for as long as @var{ttl}.
  11477. Additionally, when @option{--cache} is used, cached entries that have
  11478. not been accessed for @var{ttl} and that no longer have a corresponding
  11479. item in the store, may be deleted.
  11480. @item --negative-ttl=@var{ttl}
  11481. Similarly produce @code{Cache-Control} HTTP headers to advertise the
  11482. time-to-live (TTL) of @emph{negative} lookups---missing store items, for
  11483. which the HTTP 404 code is returned. By default, no negative TTL is
  11484. advertised.
  11485. This parameter can help adjust server load and substitute latency by
  11486. instructing cooperating clients to be more or less patient when a store
  11487. item is missing.
  11488. @item --cache-bypass-threshold=@var{size}
  11489. When used in conjunction with @option{--cache}, store items smaller than
  11490. @var{size} are immediately available, even when they are not yet in
  11491. cache. @var{size} is a size in bytes, or it can be suffixed by @code{M}
  11492. for megabytes and so on. The default is @code{10M}.
  11493. ``Cache bypass'' allows you to reduce the publication delay for clients
  11494. at the expense of possibly additional I/O and CPU use on the server
  11495. side: depending on the client access patterns, those store items can end
  11496. up being baked several times until a copy is available in cache.
  11497. Increasing the threshold may be useful for sites that have few users, or
  11498. to guarantee that users get substitutes even for store items that are
  11499. not popular.
  11500. @item --nar-path=@var{path}
  11501. Use @var{path} as the prefix for the URLs of ``nar'' files
  11502. (@pxref{Invoking guix archive, normalized archives}).
  11503. By default, nars are served at a URL such as
  11504. @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
  11505. change the @code{/nar} part to @var{path}.
  11506. @item --public-key=@var{file}
  11507. @itemx --private-key=@var{file}
  11508. Use the specific @var{file}s as the public/private key pair used to sign
  11509. the store items being published.
  11510. The files must correspond to the same key pair (the private key is used
  11511. for signing and the public key is merely advertised in the signature
  11512. metadata). They must contain keys in the canonical s-expression format
  11513. as produced by @command{guix archive --generate-key} (@pxref{Invoking
  11514. guix archive}). By default, @file{/etc/guix/signing-key.pub} and
  11515. @file{/etc/guix/signing-key.sec} are used.
  11516. @item --repl[=@var{port}]
  11517. @itemx -r [@var{port}]
  11518. Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
  11519. Reference Manual}) on @var{port} (37146 by default). This is used
  11520. primarily for debugging a running @command{guix publish} server.
  11521. @end table
  11522. Enabling @command{guix publish} on Guix System is a one-liner: just
  11523. instantiate a @code{guix-publish-service-type} service in the @code{services} field
  11524. of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
  11525. @code{guix-publish-service-type}}).
  11526. If you are instead running Guix on a ``foreign distro'', follow these
  11527. instructions:
  11528. @itemize
  11529. @item
  11530. If your host distro uses the systemd init system:
  11531. @example
  11532. # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
  11533. /etc/systemd/system/
  11534. # systemctl start guix-publish && systemctl enable guix-publish
  11535. @end example
  11536. @item
  11537. If your host distro uses the Upstart init system:
  11538. @example
  11539. # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
  11540. # start guix-publish
  11541. @end example
  11542. @item
  11543. Otherwise, proceed similarly with your distro's init system.
  11544. @end itemize
  11545. @node Invoking guix challenge
  11546. @section Invoking @command{guix challenge}
  11547. @cindex reproducible builds
  11548. @cindex verifiable builds
  11549. @cindex @command{guix challenge}
  11550. @cindex challenge
  11551. Do the binaries provided by this server really correspond to the source
  11552. code it claims to build? Is a package build process deterministic?
  11553. These are the questions the @command{guix challenge} command attempts to
  11554. answer.
  11555. The former is obviously an important question: Before using a substitute
  11556. server (@pxref{Substitutes}), one had better @emph{verify} that it
  11557. provides the right binaries, and thus @emph{challenge} it. The latter
  11558. is what enables the former: If package builds are deterministic, then
  11559. independent builds of the package should yield the exact same result,
  11560. bit for bit; if a server provides a binary different from the one
  11561. obtained locally, it may be either corrupt or malicious.
  11562. We know that the hash that shows up in @file{/gnu/store} file names is
  11563. the hash of all the inputs of the process that built the file or
  11564. directory---compilers, libraries, build scripts,
  11565. etc. (@pxref{Introduction}). Assuming deterministic build processes,
  11566. one store file name should map to exactly one build output.
  11567. @command{guix challenge} checks whether there is, indeed, a single
  11568. mapping by comparing the build outputs of several independent builds of
  11569. any given store item.
  11570. The command output looks like this:
  11571. @smallexample
  11572. $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER-1} https://guix.example.org"
  11573. updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER-1}'... 100.0%
  11574. updating list of substitutes from 'https://guix.example.org'... 100.0%
  11575. /gnu/store/@dots{}-openssl-1.0.2d contents differ:
  11576. local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
  11577. https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
  11578. https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
  11579. differing files:
  11580. /lib/libcrypto.so.1.1
  11581. /lib/libssl.so.1.1
  11582. /gnu/store/@dots{}-git-2.5.0 contents differ:
  11583. local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
  11584. https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
  11585. https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
  11586. differing file:
  11587. /libexec/git-core/git-fsck
  11588. /gnu/store/@dots{}-pius-2.1.1 contents differ:
  11589. local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
  11590. https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
  11591. https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
  11592. differing file:
  11593. /share/man/man1/pius.1.gz
  11594. @dots{}
  11595. 6,406 store items were analyzed:
  11596. - 4,749 (74.1%) were identical
  11597. - 525 (8.2%) differed
  11598. - 1,132 (17.7%) were inconclusive
  11599. @end smallexample
  11600. @noindent
  11601. In this example, @command{guix challenge} first scans the store to
  11602. determine the set of locally-built derivations---as opposed to store
  11603. items that were downloaded from a substitute server---and then queries
  11604. all the substitute servers. It then reports those store items for which
  11605. the servers obtained a result different from the local build.
  11606. @cindex non-determinism, in package builds
  11607. As an example, @code{guix.example.org} always gets a different answer.
  11608. Conversely, @code{@value{SUBSTITUTE-SERVER-1}} agrees with local builds, except in the
  11609. case of Git. This might indicate that the build process of Git is
  11610. non-deterministic, meaning that its output varies as a function of
  11611. various things that Guix does not fully control, in spite of building
  11612. packages in isolated environments (@pxref{Features}). Most common
  11613. sources of non-determinism include the addition of timestamps in build
  11614. results, the inclusion of random numbers, and directory listings sorted
  11615. by inode number. See @uref{https://reproducible-builds.org/docs/}, for
  11616. more information.
  11617. To find out what is wrong with this Git binary, the easiest approach is
  11618. to run:
  11619. @example
  11620. guix challenge git \
  11621. --diff=diffoscope \
  11622. --substitute-urls="https://@value{SUBSTITUTE-SERVER-1} https://guix.example.org"
  11623. @end example
  11624. This automatically invokes @command{diffoscope}, which displays detailed
  11625. information about files that differ.
  11626. Alternatively, we can do something along these lines (@pxref{Invoking guix
  11627. archive}):
  11628. @example
  11629. $ wget -q -O - https://@value{SUBSTITUTE-SERVER-1}/nar/lzip/@dots{}-git-2.5.0 \
  11630. | lzip -d | guix archive -x /tmp/git
  11631. $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
  11632. @end example
  11633. This command shows the difference between the files resulting from the
  11634. local build, and the files resulting from the build on
  11635. @code{@value{SUBSTITUTE-SERVER-1}} (@pxref{Overview, Comparing and Merging Files,,
  11636. diffutils, Comparing and Merging Files}). The @command{diff} command
  11637. works great for text files. When binary files differ, a better option
  11638. is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
  11639. visualize differences for all kinds of files.
  11640. Once you have done that work, you can tell whether the differences are due
  11641. to a non-deterministic build process or to a malicious server. We try
  11642. hard to remove sources of non-determinism in packages to make it easier
  11643. to verify substitutes, but of course, this is a process that
  11644. involves not just Guix, but a large part of the free software community.
  11645. In the meantime, @command{guix challenge} is one tool to help address
  11646. the problem.
  11647. If you are writing packages for Guix, you are encouraged to check
  11648. whether @code{@value{SUBSTITUTE-SERVER-1}} and other substitute servers obtain the
  11649. same build result as you did with:
  11650. @example
  11651. $ guix challenge @var{package}
  11652. @end example
  11653. @noindent
  11654. where @var{package} is a package specification such as
  11655. @code{guile@@2.0} or @code{glibc:debug}.
  11656. The general syntax is:
  11657. @example
  11658. guix challenge @var{options} [@var{packages}@dots{}]
  11659. @end example
  11660. When a difference is found between the hash of a locally-built item and
  11661. that of a server-provided substitute, or among substitutes provided by
  11662. different servers, the command displays it as in the example above and
  11663. its exit code is 2 (other non-zero exit codes denote other kinds of
  11664. errors).
  11665. The one option that matters is:
  11666. @table @code
  11667. @item --substitute-urls=@var{urls}
  11668. Consider @var{urls} the whitespace-separated list of substitute source
  11669. URLs to compare to.
  11670. @item --diff=@var{mode}
  11671. Upon mismatches, show differences according to @var{mode}, one of:
  11672. @table @asis
  11673. @item @code{simple} (the default)
  11674. Show the list of files that differ.
  11675. @item @code{diffoscope}
  11676. @itemx @var{command}
  11677. Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
  11678. two directories whose contents do not match.
  11679. When @var{command} is an absolute file name, run @var{command} instead
  11680. of Diffoscope.
  11681. @item @code{none}
  11682. Do not show further details about the differences.
  11683. @end table
  11684. Thus, unless @option{--diff=none} is passed, @command{guix challenge}
  11685. downloads the store items from the given substitute servers so that it
  11686. can compare them.
  11687. @item --verbose
  11688. @itemx -v
  11689. Show details about matches (identical contents) in addition to
  11690. information about mismatches.
  11691. @end table
  11692. @node Invoking guix copy
  11693. @section Invoking @command{guix copy}
  11694. @cindex copy, of store items, over SSH
  11695. @cindex SSH, copy of store items
  11696. @cindex sharing store items across machines
  11697. @cindex transferring store items across machines
  11698. The @command{guix copy} command copies items from the store of one
  11699. machine to that of another machine over a secure shell (SSH)
  11700. connection@footnote{This command is available only when Guile-SSH was
  11701. found. @xref{Requirements}, for details.}. For example, the following
  11702. command copies the @code{coreutils} package, the user's profile, and all
  11703. their dependencies over to @var{host}, logged in as @var{user}:
  11704. @example
  11705. guix copy --to=@var{user}@@@var{host} \
  11706. coreutils $(readlink -f ~/.guix-profile)
  11707. @end example
  11708. If some of the items to be copied are already present on @var{host},
  11709. they are not actually sent.
  11710. The command below retrieves @code{libreoffice} and @code{gimp} from
  11711. @var{host}, assuming they are available there:
  11712. @example
  11713. guix copy --from=@var{host} libreoffice gimp
  11714. @end example
  11715. The SSH connection is established using the Guile-SSH client, which is
  11716. compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
  11717. @file{~/.ssh/config}, and uses the SSH agent for authentication.
  11718. The key used to sign items that are sent must be accepted by the remote
  11719. machine. Likewise, the key used by the remote machine to sign items you
  11720. are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
  11721. own daemon. @xref{Invoking guix archive}, for more information about
  11722. store item authentication.
  11723. The general syntax is:
  11724. @example
  11725. guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
  11726. @end example
  11727. You must always specify one of the following options:
  11728. @table @code
  11729. @item --to=@var{spec}
  11730. @itemx --from=@var{spec}
  11731. Specify the host to send to or receive from. @var{spec} must be an SSH
  11732. spec such as @code{example.org}, @code{charlie@@example.org}, or
  11733. @code{charlie@@example.org:2222}.
  11734. @end table
  11735. The @var{items} can be either package names, such as @code{gimp}, or
  11736. store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
  11737. When specifying the name of a package to send, it is first built if
  11738. needed, unless @option{--dry-run} was specified. Common build options
  11739. are supported (@pxref{Common Build Options}).
  11740. @node Invoking guix container
  11741. @section Invoking @command{guix container}
  11742. @cindex container
  11743. @cindex @command{guix container}
  11744. @quotation Note
  11745. As of version @value{VERSION}, this tool is experimental. The interface
  11746. is subject to radical change in the future.
  11747. @end quotation
  11748. The purpose of @command{guix container} is to manipulate processes
  11749. running within an isolated environment, commonly known as a
  11750. ``container'', typically created by the @command{guix shell}
  11751. (@pxref{Invoking guix shell}) and @command{guix system container}
  11752. (@pxref{Invoking guix system}) commands.
  11753. The general syntax is:
  11754. @example
  11755. guix container @var{action} @var{options}@dots{}
  11756. @end example
  11757. @var{action} specifies the operation to perform with a container, and
  11758. @var{options} specifies the context-specific arguments for the action.
  11759. The following actions are available:
  11760. @table @code
  11761. @item exec
  11762. Execute a command within the context of a running container.
  11763. The syntax is:
  11764. @example
  11765. guix container exec @var{pid} @var{program} @var{arguments}@dots{}
  11766. @end example
  11767. @var{pid} specifies the process ID of the running container.
  11768. @var{program} specifies an executable file name within the root file
  11769. system of the container. @var{arguments} are the additional options that
  11770. will be passed to @var{program}.
  11771. The following command launches an interactive login shell inside a
  11772. Guix system container, started by @command{guix system container}, and whose
  11773. process ID is 9001:
  11774. @example
  11775. guix container exec 9001 /run/current-system/profile/bin/bash --login
  11776. @end example
  11777. Note that the @var{pid} cannot be the parent process of a container. It
  11778. must be PID 1 of the container or one of its child processes.
  11779. @end table
  11780. @node Invoking guix weather
  11781. @section Invoking @command{guix weather}
  11782. Occasionally you're grumpy because substitutes are lacking and you end
  11783. up building packages by yourself (@pxref{Substitutes}). The
  11784. @command{guix weather} command reports on substitute availability on the
  11785. specified servers so you can have an idea of whether you'll be grumpy
  11786. today. It can sometimes be useful info as a user, but it is primarily
  11787. useful to people running @command{guix publish} (@pxref{Invoking guix
  11788. publish}).
  11789. @cindex statistics, for substitutes
  11790. @cindex availability of substitutes
  11791. @cindex substitute availability
  11792. @cindex weather, substitute availability
  11793. Here's a sample run:
  11794. @example
  11795. $ guix weather --substitute-urls=https://guix.example.org
  11796. computing 5,872 package derivations for x86_64-linux...
  11797. looking for 6,128 store items on https://guix.example.org..
  11798. updating list of substitutes from 'https://guix.example.org'... 100.0%
  11799. https://guix.example.org
  11800. 43.4% substitutes available (2,658 out of 6,128)
  11801. 7,032.5 MiB of nars (compressed)
  11802. 19,824.2 MiB on disk (uncompressed)
  11803. 0.030 seconds per request (182.9 seconds in total)
  11804. 33.5 requests per second
  11805. 9.8% (342 out of 3,470) of the missing items are queued
  11806. 867 queued builds
  11807. x86_64-linux: 518 (59.7%)
  11808. i686-linux: 221 (25.5%)
  11809. aarch64-linux: 128 (14.8%)
  11810. build rate: 23.41 builds per hour
  11811. x86_64-linux: 11.16 builds per hour
  11812. i686-linux: 6.03 builds per hour
  11813. aarch64-linux: 6.41 builds per hour
  11814. @end example
  11815. @cindex continuous integration, statistics
  11816. As you can see, it reports the fraction of all the packages for which
  11817. substitutes are available on the server---regardless of whether
  11818. substitutes are enabled, and regardless of whether this server's signing
  11819. key is authorized. It also reports the size of the compressed archives
  11820. (``nars'') provided by the server, the size the corresponding store
  11821. items occupy in the store (assuming deduplication is turned off), and
  11822. the server's throughput. The second part gives continuous integration
  11823. (CI) statistics, if the server supports it. In addition, using the
  11824. @option{--coverage} option, @command{guix weather} can list ``important''
  11825. package substitutes missing on the server (see below).
  11826. To achieve that, @command{guix weather} queries over HTTP(S) meta-data
  11827. (@dfn{narinfos}) for all the relevant store items. Like @command{guix
  11828. challenge}, it ignores signatures on those substitutes, which is
  11829. innocuous since the command only gathers statistics and cannot install
  11830. those substitutes.
  11831. The general syntax is:
  11832. @example
  11833. guix weather @var{options}@dots{} [@var{packages}@dots{}]
  11834. @end example
  11835. When @var{packages} is omitted, @command{guix weather} checks the availability
  11836. of substitutes for @emph{all} the packages, or for those specified with
  11837. @option{--manifest}; otherwise it only considers the specified packages. It
  11838. is also possible to query specific system types with @option{--system}.
  11839. @command{guix weather} exits with a non-zero code when the fraction of
  11840. available substitutes is below 100%.
  11841. The available options are listed below.
  11842. @table @code
  11843. @item --substitute-urls=@var{urls}
  11844. @var{urls} is the space-separated list of substitute server URLs to
  11845. query. When this option is omitted, the default set of substitute
  11846. servers is queried.
  11847. @item --system=@var{system}
  11848. @itemx -s @var{system}
  11849. Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
  11850. option can be repeated, in which case @command{guix weather} will query
  11851. substitutes for several system types.
  11852. @item --manifest=@var{file}
  11853. Instead of querying substitutes for all the packages, only ask for those
  11854. specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
  11855. with the @code{-m} option of @command{guix package} (@pxref{Invoking
  11856. guix package}).
  11857. This option can be repeated several times, in which case the manifests
  11858. are concatenated.
  11859. @item --coverage[=@var{count}]
  11860. @itemx -c [@var{count}]
  11861. Report on substitute coverage for packages: list packages with at least
  11862. @var{count} dependents (zero by default) for which substitutes are
  11863. unavailable. Dependent packages themselves are not listed: if @var{b} depends
  11864. on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
  11865. @var{b} usually lacks substitutes as well. The result looks like this:
  11866. @example
  11867. $ guix weather --substitute-urls=@value{SUBSTITUTE-URLS} -c 10
  11868. computing 8,983 package derivations for x86_64-linux...
  11869. looking for 9,343 store items on @value{SUBSTITUTE-URLS}...
  11870. updating substitutes from '@value{SUBSTITUTE-URLS}'... 100.0%
  11871. @value{SUBSTITUTE-URLS}
  11872. 64.7% substitutes available (6,047 out of 9,343)
  11873. @dots{}
  11874. 2502 packages are missing from '@value{SUBSTITUTE-URLS}' for 'x86_64-linux', among which:
  11875. 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
  11876. 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
  11877. 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
  11878. @dots{}
  11879. @end example
  11880. What this example shows is that @code{kcoreaddons} and presumably the 58
  11881. packages that depend on it have no substitutes at
  11882. @code{@value{SUBSTITUTE-SERVER-1}}; likewise for @code{qgpgme} and the 46
  11883. packages that depend on it.
  11884. If you are a Guix developer, or if you are taking care of this build farm,
  11885. you'll probably want to have a closer look at these packages: they may simply
  11886. fail to build.
  11887. @item --display-missing
  11888. Display the list of store items for which substitutes are missing.
  11889. @end table
  11890. @node Invoking guix processes
  11891. @section Invoking @command{guix processes}
  11892. The @command{guix processes} command can be useful to developers and system
  11893. administrators, especially on multi-user machines and on build farms: it lists
  11894. the current sessions (connections to the daemon), as well as information about
  11895. the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
  11896. started with @option{--listen} specifying a TCP endpoint, are @emph{not}
  11897. listed.}. Here's an example of the information it returns:
  11898. @example
  11899. $ sudo guix processes
  11900. SessionPID: 19002
  11901. ClientPID: 19090
  11902. ClientCommand: guix shell python
  11903. SessionPID: 19402
  11904. ClientPID: 19367
  11905. ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
  11906. SessionPID: 19444
  11907. ClientPID: 19419
  11908. ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
  11909. LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
  11910. LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
  11911. LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
  11912. ChildPID: 20495
  11913. ChildCommand: guix offload x86_64-linux 7200 1 28800
  11914. ChildPID: 27733
  11915. ChildCommand: guix offload x86_64-linux 7200 1 28800
  11916. ChildPID: 27793
  11917. ChildCommand: guix offload x86_64-linux 7200 1 28800
  11918. @end example
  11919. In this example we see that @command{guix-daemon} has three clients:
  11920. @command{guix environment}, @command{guix publish}, and the Cuirass continuous
  11921. integration tool; their process identifier (PID) is given by the
  11922. @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
  11923. @command{guix-daemon} sub-process of this particular session.
  11924. The @code{LockHeld} fields show which store items are currently locked
  11925. by this session, which corresponds to store items being built or
  11926. substituted (the @code{LockHeld} field is not displayed when
  11927. @command{guix processes} is not running as root). Last, by looking at
  11928. the @code{ChildPID} and @code{ChildCommand} fields, we understand that
  11929. these three builds are being offloaded (@pxref{Daemon Offload Setup}).
  11930. The output is in Recutils format so we can use the handy @command{recsel}
  11931. command to select sessions of interest (@pxref{Selection Expressions,,,
  11932. recutils, GNU recutils manual}). As an example, the command shows the command
  11933. line and PID of the client that triggered the build of a Perl package:
  11934. @example
  11935. $ sudo guix processes | \
  11936. recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
  11937. ClientPID: 19419
  11938. ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
  11939. @end example
  11940. Additional options are listed below.
  11941. @table @code
  11942. @item --format=@var{format}
  11943. @itemx -f @var{format}
  11944. Produce output in the specified @var{format}, one of:
  11945. @table @code
  11946. @item recutils
  11947. The default option. It outputs a set of Session recutils records
  11948. that include each @code{ChildProcess} as a field.
  11949. @item normalized
  11950. Normalize the output records into record sets (@pxref{Record Sets,,,
  11951. recutils, GNU recutils manual}). Normalizing into record sets allows
  11952. joins across record types. The example below lists the PID of each
  11953. @code{ChildProcess} and the associated PID for @code{Session} that
  11954. spawned the @code{ChildProcess} where the @code{Session} was started
  11955. using @command{guix build}.
  11956. @example
  11957. $ guix processes --format=normalized | \
  11958. recsel \
  11959. -j Session \
  11960. -t ChildProcess \
  11961. -p Session.PID,PID \
  11962. -e 'Session.ClientCommand ~ "guix build"'
  11963. PID: 4435
  11964. Session_PID: 4278
  11965. PID: 4554
  11966. Session_PID: 4278
  11967. PID: 4646
  11968. Session_PID: 4278
  11969. @end example
  11970. @end table
  11971. @end table
  11972. @node System Configuration
  11973. @chapter System Configuration
  11974. @cindex system configuration
  11975. Guix System supports a consistent whole-system configuration
  11976. mechanism. By that we mean that all aspects of the global system
  11977. configuration---such as the available system services, timezone and
  11978. locale settings, user accounts---are declared in a single place. Such
  11979. a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
  11980. One of the advantages of putting all the system configuration under the
  11981. control of Guix is that it supports transactional system upgrades, and
  11982. makes it possible to roll back to a previous system instantiation,
  11983. should something go wrong with the new one (@pxref{Features}). Another
  11984. advantage is that it makes it easy to replicate the exact same configuration
  11985. across different machines, or at different points in time, without
  11986. having to resort to additional administration tools layered on top of
  11987. the own tools of the system.
  11988. @c Yes, we're talking of Puppet, Chef, & co. here. ↑
  11989. This section describes this mechanism. First we focus on the system
  11990. administrator's viewpoint---explaining how the system is configured and
  11991. instantiated. Then we show how this mechanism can be extended, for
  11992. instance to support new system services.
  11993. @menu
  11994. * Using the Configuration System:: Customizing your GNU system.
  11995. * operating-system Reference:: Detail of operating-system declarations.
  11996. * File Systems:: Configuring file system mounts.
  11997. * Mapped Devices:: Block device extra processing.
  11998. * Swap Space:: Backing RAM with disk space.
  11999. * User Accounts:: Specifying user accounts.
  12000. * Keyboard Layout:: How the system interprets key strokes.
  12001. * Locales:: Language and cultural convention settings.
  12002. * Services:: Specifying system services.
  12003. * Setuid Programs:: Programs running with root privileges.
  12004. * X.509 Certificates:: Authenticating HTTPS servers.
  12005. * Name Service Switch:: Configuring libc's name service switch.
  12006. * Initial RAM Disk:: Linux-Libre bootstrapping.
  12007. * Bootloader Configuration:: Configuring the boot loader.
  12008. * Invoking guix system:: Instantiating a system configuration.
  12009. * Invoking guix deploy:: Deploying a system configuration to a remote host.
  12010. * Running Guix in a VM:: How to run Guix System in a virtual machine.
  12011. * Defining Services:: Adding new service definitions.
  12012. @end menu
  12013. @node Using the Configuration System
  12014. @section Using the Configuration System
  12015. The operating system is configured by providing an
  12016. @code{operating-system} declaration in a file that can then be passed to
  12017. the @command{guix system} command (@pxref{Invoking guix system}). A
  12018. simple setup, with the default system services, the default Linux-Libre
  12019. kernel, initial RAM disk, and boot loader looks like this:
  12020. @findex operating-system
  12021. @lisp
  12022. @include os-config-bare-bones.texi
  12023. @end lisp
  12024. This example should be self-describing. Some of the fields defined
  12025. above, such as @code{host-name} and @code{bootloader}, are mandatory.
  12026. Others, such as @code{packages} and @code{services}, can be omitted, in
  12027. which case they get a default value.
  12028. Below we discuss the effect of some of the most important fields
  12029. (@pxref{operating-system Reference}, for details about all the available
  12030. fields), and how to @dfn{instantiate} the operating system using
  12031. @command{guix system}.
  12032. @unnumberedsubsec Bootloader
  12033. @cindex legacy boot, on Intel machines
  12034. @cindex BIOS boot, on Intel machines
  12035. @cindex UEFI boot
  12036. @cindex EFI boot
  12037. The @code{bootloader} field describes the method that will be used to boot
  12038. your system. Machines based on Intel processors can boot in ``legacy'' BIOS
  12039. mode, as in the example above. However, more recent machines rely instead on
  12040. the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
  12041. the @code{bootloader} field should contain something along these lines:
  12042. @lisp
  12043. (bootloader-configuration
  12044. (bootloader grub-efi-bootloader)
  12045. (targets '("/boot/efi")))
  12046. @end lisp
  12047. @xref{Bootloader Configuration}, for more information on the available
  12048. configuration options.
  12049. @unnumberedsubsec Globally-Visible Packages
  12050. @vindex %base-packages
  12051. The @code{packages} field lists packages that will be globally visible
  12052. on the system, for all user accounts---i.e., in every user's @env{PATH}
  12053. environment variable---in addition to the per-user profiles
  12054. (@pxref{Invoking guix package}). The @code{%base-packages} variable
  12055. provides all the tools one would expect for basic user and administrator
  12056. tasks---including the GNU Core Utilities, the GNU Networking Utilities,
  12057. the @command{mg} lightweight text editor, @command{find}, @command{grep},
  12058. etc. The example above adds GNU@tie{}Screen to those,
  12059. taken from the @code{(gnu packages screen)}
  12060. module (@pxref{Package Modules}). The
  12061. @code{(list package output)} syntax can be used to add a specific output
  12062. of a package:
  12063. @lisp
  12064. (use-modules (gnu packages))
  12065. (use-modules (gnu packages dns))
  12066. (operating-system
  12067. ;; ...
  12068. (packages (cons (list isc-bind "utils")
  12069. %base-packages)))
  12070. @end lisp
  12071. @findex specification->package
  12072. Referring to packages by variable name, like @code{isc-bind} above, has
  12073. the advantage of being unambiguous; it also allows typos and such to be
  12074. diagnosed right away as ``unbound variables''. The downside is that one
  12075. needs to know which module defines which package, and to augment the
  12076. @code{use-package-modules} line accordingly. To avoid that, one can use
  12077. the @code{specification->package} procedure of the @code{(gnu packages)}
  12078. module, which returns the best package for a given name or name and
  12079. version:
  12080. @lisp
  12081. (use-modules (gnu packages))
  12082. (operating-system
  12083. ;; ...
  12084. (packages (append (map specification->package
  12085. '("tcpdump" "htop" "gnupg@@2.0"))
  12086. %base-packages)))
  12087. @end lisp
  12088. @unnumberedsubsec System Services
  12089. @cindex services
  12090. @vindex %base-services
  12091. The @code{services} field lists @dfn{system services} to be made
  12092. available when the system starts (@pxref{Services}).
  12093. The @code{operating-system} declaration above specifies that, in
  12094. addition to the basic services, we want the OpenSSH secure shell
  12095. daemon listening on port 2222 (@pxref{Networking Services,
  12096. @code{openssh-service-type}}). Under the hood,
  12097. @code{openssh-service-type} arranges so that @command{sshd} is started with the
  12098. right command-line options, possibly with supporting configuration files
  12099. generated as needed (@pxref{Defining Services}).
  12100. @cindex customization, of services
  12101. @findex modify-services
  12102. Occasionally, instead of using the base services as is, you will want to
  12103. customize them. To do this, use @code{modify-services} (@pxref{Service
  12104. Reference, @code{modify-services}}) to modify the list.
  12105. @anchor{auto-login to TTY} For example, suppose you want to modify
  12106. @code{guix-daemon} and Mingetty (the console log-in) in the
  12107. @code{%base-services} list (@pxref{Base Services,
  12108. @code{%base-services}}). To do that, you can write the following in
  12109. your operating system declaration:
  12110. @lisp
  12111. (define %my-services
  12112. ;; My very own list of services.
  12113. (modify-services %base-services
  12114. (guix-service-type config =>
  12115. (guix-configuration
  12116. (inherit config)
  12117. ;; Fetch substitutes from example.org.
  12118. (substitute-urls
  12119. (list "https://example.org/guix"
  12120. "https://ci.guix.gnu.org"))))
  12121. (mingetty-service-type config =>
  12122. (mingetty-configuration
  12123. (inherit config)
  12124. ;; Automatically log in as "guest".
  12125. (auto-login "guest")))))
  12126. (operating-system
  12127. ;; @dots{}
  12128. (services %my-services))
  12129. @end lisp
  12130. This changes the configuration---i.e., the service parameters---of the
  12131. @code{guix-service-type} instance, and that of all the
  12132. @code{mingetty-service-type} instances in the @code{%base-services} list
  12133. (@pxref{Auto-Login to a Specific TTY, see the cookbook for how to
  12134. auto-login one user to a specific TTY,, guix-cookbook, GNU Guix Cookbook})).
  12135. Observe how this is accomplished: first, we arrange for the original
  12136. configuration to be bound to the identifier @code{config} in the
  12137. @var{body}, and then we write the @var{body} so that it evaluates to the
  12138. desired configuration. In particular, notice how we use @code{inherit}
  12139. to create a new configuration which has the same values as the old
  12140. configuration, but with a few modifications.
  12141. @cindex encrypted disk
  12142. The configuration for a typical ``desktop'' usage, with an encrypted
  12143. root partition, a swap file on the root partition, the X11 display
  12144. server, GNOME and Xfce (users can choose which of these desktop
  12145. environments to use at the log-in screen by pressing @kbd{F1}), network
  12146. management, power management, and more, would look like this:
  12147. @lisp
  12148. @include os-config-desktop.texi
  12149. @end lisp
  12150. A graphical system with a choice of lightweight window managers
  12151. instead of full-blown desktop environments would look like this:
  12152. @lisp
  12153. @include os-config-lightweight-desktop.texi
  12154. @end lisp
  12155. This example refers to the @file{/boot/efi} file system by its UUID,
  12156. @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
  12157. as returned by the @command{blkid} command.
  12158. @xref{Desktop Services}, for the exact list of services provided by
  12159. @code{%desktop-services}. @xref{X.509 Certificates}, for background
  12160. information about the @code{nss-certs} package that is used here.
  12161. Again, @code{%desktop-services} is just a list of service objects. If
  12162. you want to remove services from there, you can do so using the
  12163. procedures for list filtering (@pxref{SRFI-1 Filtering and
  12164. Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
  12165. following expression returns a list that contains all the services in
  12166. @code{%desktop-services} minus the Avahi service:
  12167. @lisp
  12168. (remove (lambda (service)
  12169. (eq? (service-kind service) avahi-service-type))
  12170. %desktop-services)
  12171. @end lisp
  12172. Alternatively, the @code{modify-services} macro can be used:
  12173. @lisp
  12174. (modify-services %desktop-services
  12175. (delete avahi-service-type))
  12176. @end lisp
  12177. @unnumberedsubsec Instantiating the System
  12178. Assuming the @code{operating-system} declaration
  12179. is stored in the @file{my-system-config.scm}
  12180. file, the @command{guix system reconfigure my-system-config.scm} command
  12181. instantiates that configuration, and makes it the default GRUB boot
  12182. entry (@pxref{Invoking guix system}).
  12183. The normal way to change the system configuration is by updating this
  12184. file and re-running @command{guix system reconfigure}. One should never
  12185. have to touch files in @file{/etc} or to run commands that modify the
  12186. system state such as @command{useradd} or @command{grub-install}. In
  12187. fact, you must avoid that since that would not only void your warranty
  12188. but also prevent you from rolling back to previous versions of your
  12189. system, should you ever need to.
  12190. @cindex roll-back, of the operating system
  12191. Speaking of roll-back, each time you run @command{guix system
  12192. reconfigure}, a new @dfn{generation} of the system is created---without
  12193. modifying or deleting previous generations. Old system generations get
  12194. an entry in the bootloader boot menu, allowing you to boot them in case
  12195. something went wrong with the latest generation. Reassuring, no? The
  12196. @command{guix system list-generations} command lists the system
  12197. generations available on disk. It is also possible to roll back the
  12198. system via the commands @command{guix system roll-back} and
  12199. @command{guix system switch-generation}.
  12200. Although the @command{guix system reconfigure} command will not modify
  12201. previous generations, you must take care when the current generation is not
  12202. the latest (e.g., after invoking @command{guix system roll-back}), since
  12203. the operation might overwrite a later generation (@pxref{Invoking guix
  12204. system}).
  12205. @unnumberedsubsec The Programming Interface
  12206. At the Scheme level, the bulk of an @code{operating-system} declaration
  12207. is instantiated with the following monadic procedure (@pxref{The Store
  12208. Monad}):
  12209. @deffn {Monadic Procedure} operating-system-derivation os
  12210. Return a derivation that builds @var{os}, an @code{operating-system}
  12211. object (@pxref{Derivations}).
  12212. The output of the derivation is a single directory that refers to all
  12213. the packages, configuration files, and other supporting files needed to
  12214. instantiate @var{os}.
  12215. @end deffn
  12216. This procedure is provided by the @code{(gnu system)} module. Along
  12217. with @code{(gnu services)} (@pxref{Services}), this module contains the
  12218. guts of Guix System. Make sure to visit it!
  12219. @node operating-system Reference
  12220. @section @code{operating-system} Reference
  12221. This section summarizes all the options available in
  12222. @code{operating-system} declarations (@pxref{Using the Configuration
  12223. System}).
  12224. @deftp {Data Type} operating-system
  12225. This is the data type representing an operating system configuration.
  12226. By that, we mean all the global system configuration, not per-user
  12227. configuration (@pxref{Using the Configuration System}).
  12228. @table @asis
  12229. @item @code{kernel} (default: @code{linux-libre})
  12230. The package object of the operating system kernel to
  12231. use@footnote{Currently only the Linux-libre kernel is fully supported.
  12232. Using GNU@tie{}mach with the GNU@tie{}Hurd is experimental and only
  12233. available when building a virtual machine disk image.}.
  12234. @cindex hurd
  12235. @item @code{hurd} (default: @code{#f})
  12236. The package object of the Hurd to be started by the kernel. When this
  12237. field is set, produce a GNU/Hurd operating system. In that case,
  12238. @code{kernel} must also be set to the @code{gnumach} package---the
  12239. microkernel the Hurd runs on.
  12240. @quotation Warning
  12241. This feature is experimental and only supported for disk images.
  12242. @end quotation
  12243. @item @code{kernel-loadable-modules} (default: '())
  12244. A list of objects (usually packages) to collect loadable kernel modules
  12245. from--e.g. @code{(list ddcci-driver-linux)}.
  12246. @item @code{kernel-arguments} (default: @code{%default-kernel-arguments})
  12247. List of strings or gexps representing additional arguments to pass on
  12248. the command-line of the kernel---e.g., @code{("console=ttyS0")}.
  12249. @item @code{bootloader}
  12250. The system bootloader configuration object. @xref{Bootloader Configuration}.
  12251. @item @code{label}
  12252. This is the label (a string) as it appears in the bootloader's menu entry.
  12253. The default label includes the kernel name and version.
  12254. @item @code{keyboard-layout} (default: @code{#f})
  12255. This field specifies the keyboard layout to use in the console. It can be
  12256. either @code{#f}, in which case the default keyboard layout is used (usually
  12257. US English), or a @code{<keyboard-layout>} record. @xref{Keyboard Layout},
  12258. for more information.
  12259. This keyboard layout is in effect as soon as the kernel has booted. For
  12260. instance, it is the keyboard layout in effect when you type a passphrase if
  12261. your root file system is on a @code{luks-device-mapping} mapped device
  12262. (@pxref{Mapped Devices}).
  12263. @quotation Note
  12264. This does @emph{not} specify the keyboard layout used by the bootloader, nor
  12265. that used by the graphical display server. @xref{Bootloader Configuration},
  12266. for information on how to specify the bootloader's keyboard layout. @xref{X
  12267. Window}, for information on how to specify the keyboard layout used by the X
  12268. Window System.
  12269. @end quotation
  12270. @item @code{initrd-modules} (default: @code{%base-initrd-modules})
  12271. @cindex initrd
  12272. @cindex initial RAM disk
  12273. The list of Linux kernel modules that need to be available in the
  12274. initial RAM disk. @xref{Initial RAM Disk}.
  12275. @item @code{initrd} (default: @code{base-initrd})
  12276. A procedure that returns an initial RAM disk for the Linux
  12277. kernel. This field is provided to support low-level customization and
  12278. should rarely be needed for casual use. @xref{Initial RAM Disk}.
  12279. @item @code{firmware} (default: @code{%base-firmware})
  12280. @cindex firmware
  12281. List of firmware packages loadable by the operating system kernel.
  12282. The default includes firmware needed for Atheros- and Broadcom-based
  12283. WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
  12284. respectively). @xref{Hardware Considerations}, for more info on
  12285. supported hardware.
  12286. @item @code{host-name}
  12287. The host name.
  12288. @item @code{hosts-file}
  12289. @cindex hosts file
  12290. A file-like object (@pxref{G-Expressions, file-like objects}) for use as
  12291. @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
  12292. Reference Manual}). The default is a file with entries for
  12293. @code{localhost} and @var{host-name}.
  12294. @item @code{mapped-devices} (default: @code{'()})
  12295. A list of mapped devices. @xref{Mapped Devices}.
  12296. @item @code{file-systems}
  12297. A list of file systems. @xref{File Systems}.
  12298. @item @code{swap-devices} (default: @code{'()})
  12299. @cindex swap devices
  12300. A list of swap spaces. @xref{Swap Space}.
  12301. @item @code{users} (default: @code{%base-user-accounts})
  12302. @itemx @code{groups} (default: @code{%base-groups})
  12303. List of user accounts and groups. @xref{User Accounts}.
  12304. If the @code{users} list lacks a user account with UID@tie{}0, a
  12305. ``root'' account with UID@tie{}0 is automatically added.
  12306. @item @code{skeletons} (default: @code{(default-skeletons)})
  12307. A list of target file name/file-like object tuples (@pxref{G-Expressions,
  12308. file-like objects}). These are the skeleton files that will be added to
  12309. the home directory of newly-created user accounts.
  12310. For instance, a valid value may look like this:
  12311. @lisp
  12312. `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
  12313. (".guile" ,(plain-file "guile"
  12314. "(use-modules (ice-9 readline))
  12315. (activate-readline)")))
  12316. @end lisp
  12317. @item @code{issue} (default: @code{%default-issue})
  12318. A string denoting the contents of the @file{/etc/issue} file, which is
  12319. displayed when users log in on a text console.
  12320. @item @code{packages} (default: @code{%base-packages})
  12321. A list of packages to be installed in the global profile, which is accessible
  12322. at @file{/run/current-system/profile}. Each element is either a package
  12323. variable or a package/output tuple. Here's a simple example of both:
  12324. @lisp
  12325. (cons* git ; the default "out" output
  12326. (list git "send-email") ; another output of git
  12327. %base-packages) ; the default set
  12328. @end lisp
  12329. The default set includes core utilities and it is good practice to
  12330. install non-core utilities in user profiles (@pxref{Invoking guix
  12331. package}).
  12332. @item @code{timezone}
  12333. A timezone identifying string---e.g., @code{"Europe/Paris"}.
  12334. You can run the @command{tzselect} command to find out which timezone
  12335. string corresponds to your region. Choosing an invalid timezone name
  12336. causes @command{guix system} to fail.
  12337. @item @code{locale} (default: @code{"en_US.utf8"})
  12338. The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
  12339. Library Reference Manual}). @xref{Locales}, for more information.
  12340. @item @code{locale-definitions} (default: @code{%default-locale-definitions})
  12341. The list of locale definitions to be compiled and that may be used at
  12342. run time. @xref{Locales}.
  12343. @item @code{locale-libcs} (default: @code{(list @var{glibc})})
  12344. The list of GNU@tie{}libc packages whose locale data and tools are used
  12345. to build the locale definitions. @xref{Locales}, for compatibility
  12346. considerations that justify this option.
  12347. @item @code{name-service-switch} (default: @code{%default-nss})
  12348. Configuration of the libc name service switch (NSS)---a
  12349. @code{<name-service-switch>} object. @xref{Name Service Switch}, for
  12350. details.
  12351. @item @code{services} (default: @code{%base-services})
  12352. A list of service objects denoting system services. @xref{Services}.
  12353. @cindex essential services
  12354. @item @code{essential-services} (default: ...)
  12355. The list of ``essential services''---i.e., things like instances of
  12356. @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
  12357. Reference}), which are derived from the operating system definition itself.
  12358. As a user you should @emph{never} need to touch this field.
  12359. @item @code{pam-services} (default: @code{(base-pam-services)})
  12360. @cindex PAM
  12361. @cindex pluggable authentication modules
  12362. Linux @dfn{pluggable authentication module} (PAM) services.
  12363. @c FIXME: Add xref to PAM services section.
  12364. @item @code{setuid-programs} (default: @code{%setuid-programs})
  12365. List of @code{<setuid-program>}. @xref{Setuid Programs}, for more
  12366. information.
  12367. @item @code{sudoers-file} (default: @code{%sudoers-specification})
  12368. @cindex sudoers file
  12369. The contents of the @file{/etc/sudoers} file as a file-like object
  12370. (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
  12371. This file specifies which users can use the @command{sudo} command, what
  12372. they are allowed to do, and what privileges they may gain. The default
  12373. is that only @code{root} and members of the @code{wheel} group may use
  12374. @code{sudo}.
  12375. @end table
  12376. @deffn {Scheme Syntax} this-operating-system
  12377. When used in the @emph{lexical scope} of an operating system field definition,
  12378. this identifier resolves to the operating system being defined.
  12379. The example below shows how to refer to the operating system being defined in
  12380. the definition of the @code{label} field:
  12381. @lisp
  12382. (use-modules (gnu) (guix))
  12383. (operating-system
  12384. ;; ...
  12385. (label (package-full-name
  12386. (operating-system-kernel this-operating-system))))
  12387. @end lisp
  12388. It is an error to refer to @code{this-operating-system} outside an operating
  12389. system definition.
  12390. @end deffn
  12391. @end deftp
  12392. @node File Systems
  12393. @section File Systems
  12394. The list of file systems to be mounted is specified in the
  12395. @code{file-systems} field of the operating system declaration
  12396. (@pxref{Using the Configuration System}). Each file system is declared
  12397. using the @code{file-system} form, like this:
  12398. @lisp
  12399. (file-system
  12400. (mount-point "/home")
  12401. (device "/dev/sda3")
  12402. (type "ext4"))
  12403. @end lisp
  12404. As usual, some of the fields are mandatory---those shown in the example
  12405. above---while others can be omitted. These are described below.
  12406. @deftp {Data Type} file-system
  12407. Objects of this type represent file systems to be mounted. They
  12408. contain the following members:
  12409. @table @asis
  12410. @item @code{type}
  12411. This is a string specifying the type of the file system---e.g.,
  12412. @code{"ext4"}.
  12413. @item @code{mount-point}
  12414. This designates the place where the file system is to be mounted.
  12415. @item @code{device}
  12416. This names the ``source'' of the file system. It can be one of three
  12417. things: a file system label, a file system UUID, or the name of a
  12418. @file{/dev} node. Labels and UUIDs offer a way to refer to file
  12419. systems without having to hard-code their actual device
  12420. name@footnote{Note that, while it is tempting to use
  12421. @file{/dev/disk/by-uuid} and similar device names to achieve the same
  12422. result, this is not recommended: These special device nodes are created
  12423. by the udev daemon and may be unavailable at the time the device is
  12424. mounted.}.
  12425. @findex file-system-label
  12426. File system labels are created using the @code{file-system-label}
  12427. procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
  12428. plain strings. Here's an example of a file system referred to by its
  12429. label, as shown by the @command{e2label} command:
  12430. @lisp
  12431. (file-system
  12432. (mount-point "/home")
  12433. (type "ext4")
  12434. (device (file-system-label "my-home")))
  12435. @end lisp
  12436. @findex uuid
  12437. UUIDs are converted from their string representation (as shown by the
  12438. @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
  12439. @code{uuid} form expects 16-byte UUIDs as defined in
  12440. @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
  12441. form of UUID used by the ext2 family of file systems and others, but it
  12442. is different from ``UUIDs'' found in FAT file systems, for instance.},
  12443. like this:
  12444. @lisp
  12445. (file-system
  12446. (mount-point "/home")
  12447. (type "ext4")
  12448. (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
  12449. @end lisp
  12450. When the source of a file system is a mapped device (@pxref{Mapped
  12451. Devices}), its @code{device} field @emph{must} refer to the mapped
  12452. device name---e.g., @file{"/dev/mapper/root-partition"}.
  12453. This is required so that
  12454. the system knows that mounting the file system depends on having the
  12455. corresponding device mapping established.
  12456. @item @code{flags} (default: @code{'()})
  12457. This is a list of symbols denoting mount flags. Recognized flags
  12458. include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
  12459. access to special files), @code{no-suid} (ignore setuid and setgid
  12460. bits), @code{no-atime} (do not update file access times),
  12461. @code{strict-atime} (update file access time), @code{lazy-time} (only
  12462. update time on the in-memory version of the file inode), and
  12463. @code{no-exec} (disallow program execution).
  12464. @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
  12465. Manual}, for more information on these flags.
  12466. @item @code{options} (default: @code{#f})
  12467. This is either @code{#f}, or a string denoting mount options passed to
  12468. the file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C
  12469. Library Reference Manual}, for details and run @command{man 8 mount} for
  12470. options for various file systems. Note that the
  12471. @code{file-system-options->alist} and @code{alist->file-system-options}
  12472. procedures from @code{(gnu system file-systems)} can be used to convert
  12473. file system options given as an association list to the string
  12474. representation, and vice-versa.
  12475. @item @code{mount?} (default: @code{#t})
  12476. This value indicates whether to automatically mount the file system when
  12477. the system is brought up. When set to @code{#f}, the file system gets
  12478. an entry in @file{/etc/fstab} (read by the @command{mount} command) but
  12479. is not automatically mounted.
  12480. @item @code{needed-for-boot?} (default: @code{#f})
  12481. This Boolean value indicates whether the file system is needed when
  12482. booting. If that is true, then the file system is mounted when the
  12483. initial RAM disk (initrd) is loaded. This is always the case, for
  12484. instance, for the root file system.
  12485. @item @code{check?} (default: @code{#t})
  12486. This Boolean indicates whether the file system should be checked for
  12487. errors before being mounted. How and when this happens can be further
  12488. adjusted with the following options.
  12489. @item @code{skip-check-if-clean?} (default: @code{#t})
  12490. When true, this Boolean indicates that a file system check triggered
  12491. by @code{check?} may exit early if the file system is marked as
  12492. ``clean'', meaning that it was previously correctly unmounted and
  12493. should not contain errors.
  12494. Setting this to false will always force a full consistency check when
  12495. @code{check?} is true. This may take a very long time and is not
  12496. recommended on healthy systems---in fact, it may reduce reliability!
  12497. Conversely, some primitive file systems like @code{fat} do not keep
  12498. track of clean shutdowns and will perform a full scan regardless of the
  12499. value of this option.
  12500. @item @code{repair} (default: @code{'preen})
  12501. When @code{check?} finds errors, it can (try to) repair them and
  12502. continue booting. This option controls when and how to do so.
  12503. If false, try not to modify the file system at all. Checking certain
  12504. file systems like @code{jfs} may still write to the device to replay
  12505. the journal. No repairs will be attempted.
  12506. If @code{#t}, try to repair any errors found and assume ``yes'' to
  12507. all questions. This will fix the most errors, but may be risky.
  12508. If @code{'preen}, repair only errors that are safe to fix without
  12509. human interaction. What that means is left up to the developers of
  12510. each file system and may be equivalent to ``none'' or ``all''.
  12511. @item @code{create-mount-point?} (default: @code{#f})
  12512. When true, the mount point is created if it does not exist yet.
  12513. @item @code{mount-may-fail?} (default: @code{#f})
  12514. When true, this indicates that mounting this file system can fail but
  12515. that should not be considered an error. This is useful in unusual
  12516. cases; an example of this is @code{efivarfs}, a file system that can
  12517. only be mounted on EFI/UEFI systems.
  12518. @item @code{dependencies} (default: @code{'()})
  12519. This is a list of @code{<file-system>} or @code{<mapped-device>} objects
  12520. representing file systems that must be mounted or mapped devices that
  12521. must be opened before (and unmounted or closed after) this one.
  12522. As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
  12523. a dependency of @file{/sys/fs/cgroup/cpu} and
  12524. @file{/sys/fs/cgroup/memory}.
  12525. Another example is a file system that depends on a mapped device, for
  12526. example for an encrypted partition (@pxref{Mapped Devices}).
  12527. @end table
  12528. @end deftp
  12529. @deffn {Scheme Procedure} file-system-label @var{str}
  12530. This procedure returns an opaque file system label from @var{str}, a
  12531. string:
  12532. @lisp
  12533. (file-system-label "home")
  12534. @result{} #<file-system-label "home">
  12535. @end lisp
  12536. File system labels are used to refer to file systems by label rather
  12537. than by device name. See above for examples.
  12538. @end deffn
  12539. The @code{(gnu system file-systems)} exports the following useful
  12540. variables.
  12541. @defvr {Scheme Variable} %base-file-systems
  12542. These are essential file systems that are required on normal systems,
  12543. such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
  12544. below). Operating system declarations should always contain at least
  12545. these.
  12546. @end defvr
  12547. @defvr {Scheme Variable} %pseudo-terminal-file-system
  12548. This is the file system to be mounted as @file{/dev/pts}. It supports
  12549. @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
  12550. functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
  12551. Manual}). Pseudo-terminals are used by terminal emulators such as
  12552. @command{xterm}.
  12553. @end defvr
  12554. @defvr {Scheme Variable} %shared-memory-file-system
  12555. This file system is mounted as @file{/dev/shm} and is used to support
  12556. memory sharing across processes (@pxref{Memory-mapped I/O,
  12557. @code{shm_open},, libc, The GNU C Library Reference Manual}).
  12558. @end defvr
  12559. @defvr {Scheme Variable} %immutable-store
  12560. This file system performs a read-only ``bind mount'' of
  12561. @file{/gnu/store}, making it read-only for all the users including
  12562. @code{root}. This prevents against accidental modification by software
  12563. running as @code{root} or by system administrators.
  12564. The daemon itself is still able to write to the store: it remounts it
  12565. read-write in its own ``name space.''
  12566. @end defvr
  12567. @defvr {Scheme Variable} %binary-format-file-system
  12568. The @code{binfmt_misc} file system, which allows handling of arbitrary
  12569. executable file types to be delegated to user space. This requires the
  12570. @code{binfmt.ko} kernel module to be loaded.
  12571. @end defvr
  12572. @defvr {Scheme Variable} %fuse-control-file-system
  12573. The @code{fusectl} file system, which allows unprivileged users to mount
  12574. and unmount user-space FUSE file systems. This requires the
  12575. @code{fuse.ko} kernel module to be loaded.
  12576. @end defvr
  12577. The @code{(gnu system uuid)} module provides tools to deal with file
  12578. system ``unique identifiers'' (UUIDs).
  12579. @deffn {Scheme Procedure} uuid @var{str} [@var{type}]
  12580. Return an opaque UUID (unique identifier) object of the given @var{type}
  12581. (a symbol) by parsing @var{str} (a string):
  12582. @lisp
  12583. (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")
  12584. @result{} #<<uuid> type: dce bv: @dots{}>
  12585. (uuid "1234-ABCD" 'fat)
  12586. @result{} #<<uuid> type: fat bv: @dots{}>
  12587. @end lisp
  12588. @var{type} may be one of @code{dce}, @code{iso9660}, @code{fat},
  12589. @code{ntfs}, or one of the commonly found synonyms for these.
  12590. UUIDs are another way to unambiguously refer to file systems in
  12591. operating system configuration. See the examples above.
  12592. @end deffn
  12593. @node Btrfs file system
  12594. @subsection Btrfs file system
  12595. The Btrfs has special features, such as subvolumes, that merit being
  12596. explained in more details. The following section attempts to cover
  12597. basic as well as complex uses of a Btrfs file system with the Guix
  12598. System.
  12599. In its simplest usage, a Btrfs file system can be described, for
  12600. example, by:
  12601. @lisp
  12602. (file-system
  12603. (mount-point "/home")
  12604. (type "btrfs")
  12605. (device (file-system-label "my-home")))
  12606. @end lisp
  12607. The example below is more complex, as it makes use of a Btrfs
  12608. subvolume, named @code{rootfs}. The parent Btrfs file system is labeled
  12609. @code{my-btrfs-pool}, and is located on an encrypted device (hence the
  12610. dependency on @code{mapped-devices}):
  12611. @lisp
  12612. (file-system
  12613. (device (file-system-label "my-btrfs-pool"))
  12614. (mount-point "/")
  12615. (type "btrfs")
  12616. (options "subvol=rootfs")
  12617. (dependencies mapped-devices))
  12618. @end lisp
  12619. Some bootloaders, for example GRUB, only mount a Btrfs partition at its
  12620. top level during the early boot, and rely on their configuration to
  12621. refer to the correct subvolume path within that top level. The
  12622. bootloaders operating in this way typically produce their configuration
  12623. on a running system where the Btrfs partitions are already mounted and
  12624. where the subvolume information is readily available. As an example,
  12625. @command{grub-mkconfig}, the configuration generator command shipped
  12626. with GRUB, reads @file{/proc/self/mountinfo} to determine the top-level
  12627. path of a subvolume.
  12628. The Guix System produces a bootloader configuration using the operating
  12629. system configuration as its sole input; it is therefore necessary to
  12630. extract the subvolume name on which @file{/gnu/store} lives (if any)
  12631. from that operating system configuration. To better illustrate,
  12632. consider a subvolume named 'rootfs' which contains the root file system
  12633. data. In such situation, the GRUB bootloader would only see the top
  12634. level of the root Btrfs partition, e.g.:
  12635. @example
  12636. / (top level)
  12637. ├── rootfs (subvolume directory)
  12638. ├── gnu (normal directory)
  12639. ├── store (normal directory)
  12640. [...]
  12641. @end example
  12642. Thus, the subvolume name must be prepended to the @file{/gnu/store} path
  12643. of the kernel, initrd binaries and any other files referred to in the
  12644. GRUB configuration that must be found during the early boot.
  12645. The next example shows a nested hierarchy of subvolumes and
  12646. directories:
  12647. @example
  12648. / (top level)
  12649. ├── rootfs (subvolume)
  12650. ├── gnu (normal directory)
  12651. ├── store (subvolume)
  12652. [...]
  12653. @end example
  12654. This scenario would work without mounting the 'store' subvolume.
  12655. Mounting 'rootfs' is sufficient, since the subvolume name matches its
  12656. intended mount point in the file system hierarchy. Alternatively, the
  12657. 'store' subvolume could be referred to by setting the @code{subvol}
  12658. option to either @code{/rootfs/gnu/store} or @code{rootfs/gnu/store}.
  12659. Finally, a more contrived example of nested subvolumes:
  12660. @example
  12661. / (top level)
  12662. ├── root-snapshots (subvolume)
  12663. ├── root-current (subvolume)
  12664. ├── guix-store (subvolume)
  12665. [...]
  12666. @end example
  12667. Here, the 'guix-store' subvolume doesn't match its intended mount point,
  12668. so it is necessary to mount it. The subvolume must be fully specified,
  12669. by passing its file name to the @code{subvol} option. To illustrate,
  12670. the 'guix-store' subvolume could be mounted on @file{/gnu/store} by using
  12671. a file system declaration such as:
  12672. @lisp
  12673. (file-system
  12674. (device (file-system-label "btrfs-pool-1"))
  12675. (mount-point "/gnu/store")
  12676. (type "btrfs")
  12677. (options "subvol=root-snapshots/root-current/guix-store,\
  12678. compress-force=zstd,space_cache=v2"))
  12679. @end lisp
  12680. @node Mapped Devices
  12681. @section Mapped Devices
  12682. @cindex device mapping
  12683. @cindex mapped devices
  12684. The Linux kernel has a notion of @dfn{device mapping}: a block device,
  12685. such as a hard disk partition, can be @dfn{mapped} into another device,
  12686. usually in @code{/dev/mapper/},
  12687. with additional processing over the data that flows through
  12688. it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
  12689. concept of a ``mapped device'' and that of a file system: both boil down
  12690. to @emph{translating} input/output operations made on a file to
  12691. operations on its backing store. Thus, the Hurd implements mapped
  12692. devices, like file systems, using the generic @dfn{translator} mechanism
  12693. (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
  12694. typical example is encryption device mapping: all writes to the mapped
  12695. device are encrypted, and all reads are deciphered, transparently.
  12696. Guix extends this notion by considering any device or set of devices that
  12697. are @dfn{transformed} in some way to create a new device; for instance,
  12698. RAID devices are obtained by @dfn{assembling} several other devices, such
  12699. as hard disks or partitions, into a new one that behaves as one partition.
  12700. Mapped devices are declared using the @code{mapped-device} form,
  12701. defined as follows; for examples, see below.
  12702. @deftp {Data Type} mapped-device
  12703. Objects of this type represent device mappings that will be made when
  12704. the system boots up.
  12705. @table @code
  12706. @item source
  12707. This is either a string specifying the name of the block device to be mapped,
  12708. such as @code{"/dev/sda3"}, or a list of such strings when several devices
  12709. need to be assembled for creating a new one. In case of LVM this is a
  12710. string specifying name of the volume group to be mapped.
  12711. @item target
  12712. This string specifies the name of the resulting mapped device. For
  12713. kernel mappers such as encrypted devices of type @code{luks-device-mapping},
  12714. specifying @code{"my-partition"} leads to the creation of
  12715. the @code{"/dev/mapper/my-partition"} device.
  12716. For RAID devices of type @code{raid-device-mapping}, the full device name
  12717. such as @code{"/dev/md0"} needs to be given.
  12718. LVM logical volumes of type @code{lvm-device-mapping} need to
  12719. be specified as @code{"VGNAME-LVNAME"}.
  12720. @item targets
  12721. This list of strings specifies names of the resulting mapped devices in case
  12722. there are several. The format is identical to @var{target}.
  12723. @item type
  12724. This must be a @code{mapped-device-kind} object, which specifies how
  12725. @var{source} is mapped to @var{target}.
  12726. @end table
  12727. @end deftp
  12728. @defvr {Scheme Variable} luks-device-mapping
  12729. This defines LUKS block device encryption using the @command{cryptsetup}
  12730. command from the package with the same name. It relies on the
  12731. @code{dm-crypt} Linux kernel module.
  12732. @end defvr
  12733. @defvr {Scheme Variable} raid-device-mapping
  12734. This defines a RAID device, which is assembled using the @code{mdadm}
  12735. command from the package with the same name. It requires a Linux kernel
  12736. module for the appropriate RAID level to be loaded, such as @code{raid456}
  12737. for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
  12738. @end defvr
  12739. @cindex LVM, logical volume manager
  12740. @defvr {Scheme Variable} lvm-device-mapping
  12741. This defines one or more logical volumes for the Linux
  12742. @uref{https://www.sourceware.org/lvm2/, Logical Volume Manager (LVM)}.
  12743. The volume group is activated by the @command{vgchange} command from the
  12744. @code{lvm2} package.
  12745. @end defvr
  12746. @cindex disk encryption
  12747. @cindex LUKS
  12748. The following example specifies a mapping from @file{/dev/sda3} to
  12749. @file{/dev/mapper/home} using LUKS---the
  12750. @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
  12751. standard mechanism for disk encryption.
  12752. The @file{/dev/mapper/home}
  12753. device can then be used as the @code{device} of a @code{file-system}
  12754. declaration (@pxref{File Systems}).
  12755. @lisp
  12756. (mapped-device
  12757. (source "/dev/sda3")
  12758. (target "home")
  12759. (type luks-device-mapping))
  12760. @end lisp
  12761. Alternatively, to become independent of device numbering, one may obtain
  12762. the LUKS UUID (@dfn{unique identifier}) of the source device by a
  12763. command like:
  12764. @example
  12765. cryptsetup luksUUID /dev/sda3
  12766. @end example
  12767. and use it as follows:
  12768. @lisp
  12769. (mapped-device
  12770. (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
  12771. (target "home")
  12772. (type luks-device-mapping))
  12773. @end lisp
  12774. @cindex swap encryption
  12775. It is also desirable to encrypt swap space, since swap space may contain
  12776. sensitive data. One way to accomplish that is to use a swap file in a
  12777. file system on a device mapped via LUKS encryption. In this way, the
  12778. swap file is encrypted because the entire device is encrypted.
  12779. @xref{Swap Space}, or @xref{Preparing for Installation,,Disk
  12780. Partitioning}, for an example.
  12781. A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
  12782. may be declared as follows:
  12783. @lisp
  12784. (mapped-device
  12785. (source (list "/dev/sda1" "/dev/sdb1"))
  12786. (target "/dev/md0")
  12787. (type raid-device-mapping))
  12788. @end lisp
  12789. The @file{/dev/md0} device can then be used as the @code{device} of a
  12790. @code{file-system} declaration (@pxref{File Systems}).
  12791. Note that the RAID level need not be given; it is chosen during the
  12792. initial creation and formatting of the RAID device and is determined
  12793. automatically later.
  12794. LVM logical volumes ``alpha'' and ``beta'' from volume group ``vg0'' can
  12795. be declared as follows:
  12796. @lisp
  12797. (mapped-device
  12798. (source "vg0")
  12799. (targets (list "vg0-alpha" "vg0-beta"))
  12800. (type lvm-device-mapping))
  12801. @end lisp
  12802. Devices @file{/dev/mapper/vg0-alpha} and @file{/dev/mapper/vg0-beta} can
  12803. then be used as the @code{device} of a @code{file-system} declaration
  12804. (@pxref{File Systems}).
  12805. @node Swap Space
  12806. @section Swap Space
  12807. @cindex swap space
  12808. Swap space, as it is commonly called, is a disk area specifically
  12809. designated for paging: the process in charge of memory management
  12810. (the Linux kernel or Hurd's default pager) can decide that some memory
  12811. pages stored in RAM which belong to a running program but are unused
  12812. should be stored on disk instead. It unloads those from the RAM,
  12813. freeing up precious fast memory, and writes them to the swap space. If
  12814. the program tries to access that very page, the memory management
  12815. process loads it back into memory for the program to use.
  12816. A common misconception about swap is that it is only useful when small
  12817. amounts of RAM are available to the system. However, it should be noted
  12818. that kernels often use all available RAM for disk access caching to make
  12819. I/O faster, and thus paging out unused portions of program memory will
  12820. expand the RAM available for such caching.
  12821. For a more detailed description of how memory is managed from the
  12822. viewpoint of a monolithic kernel, @xref{Memory
  12823. Concepts,,, libc, The GNU C Library Reference Manual}.
  12824. The Linux kernel has support for swap partitions and swap files: the
  12825. former uses a whole disk partition for paging, whereas the second uses a
  12826. file on a file system for that (the file system driver needs to support
  12827. it). On a comparable setup, both have the same performance, so one
  12828. should consider ease of use when deciding between them. Partitions are
  12829. ``simpler'' and do not need file system support, but need to be
  12830. allocated at disk formatting time (logical volumes notwithstanding),
  12831. whereas files can be allocated and deallocated at any time.
  12832. Note that swap space is not zeroed on shutdown, so sensitive data (such
  12833. as passwords) may linger on it if it was paged out. As such, you should
  12834. consider having your swap reside on an encrypted device (@pxref{Mapped
  12835. Devices}).
  12836. @deftp {Data Type} swap-space
  12837. Objects of this type represent swap spaces. They contain the following
  12838. members:
  12839. @table @asis
  12840. @item @code{target}
  12841. The device or file to use, either a UUID, a @code{file-system-label} or
  12842. a string, as in the definition of a @code{file-system} (@pxref{File
  12843. Systems}).
  12844. @item @code{dependencies} (default: @code{'()})
  12845. A list of @code{file-system} or @code{mapped-device} objects, upon which
  12846. the availability of the space depends. Note that just like for
  12847. @code{file-system} objects, dependencies which are needed for boot and
  12848. mounted in early userspace are not managed by the Shepherd, and so
  12849. automatically filtered out for you.
  12850. @item @code{priority} (default: @code{#f})
  12851. Only supported by the Linux kernel. Either @code{#f} to disable swap
  12852. priority, or an integer between 0 and 32767. The kernel will first use
  12853. swap spaces of higher priority when paging, and use same priority spaces
  12854. on a round-robin basis. The kernel will use swap spaces without a set
  12855. priority after prioritized spaces, and in the order that they appeared in
  12856. (not round-robin).
  12857. @item @code{discard?} (default: @code{#f})
  12858. Only supported by the Linux kernel. When true, the kernel will notify
  12859. the disk controller of discarded pages, for example with the TRIM
  12860. operation on Solid State Drives.
  12861. @end table
  12862. @end deftp
  12863. Here are some examples:
  12864. @lisp
  12865. (swap-space (target (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
  12866. @end lisp
  12867. Use the swap partition with the given UUID@. You can learn the UUID of a
  12868. Linux swap partition by running @command{swaplabel @var{device}}, where
  12869. @var{device} is the @file{/dev} file name of that partition.
  12870. @lisp
  12871. (swap-space
  12872. (target (file-system-label "swap"))
  12873. (dependencies mapped-devices))
  12874. @end lisp
  12875. Use the partition with label @code{swap}, which can be found after all
  12876. the @var{mapped-devices} mapped devices have been opened. Again, the
  12877. @command{swaplabel} command allows you to view and change the label of a
  12878. Linux swap partition.
  12879. Here's a more involved example with the corresponding @code{file-systems} part
  12880. of an @code{operating-system} declaration.
  12881. @lisp
  12882. (file-systems
  12883. (list (file-system
  12884. (device (file-system-label "root"))
  12885. (mount-point "/")
  12886. (type "ext4"))
  12887. (file-system
  12888. (device (file-system-label "btrfs"))
  12889. (mount-point "/btrfs")
  12890. (type "btrfs"))))
  12891. (swap-devices
  12892. (list
  12893. (swap-space
  12894. (target "/btrfs/swapfile")
  12895. (dependencies (filter (file-system-mount-point-predicate "/btrfs")
  12896. file-systems)))))
  12897. @end lisp
  12898. Use the file @file{/btrfs/swapfile} as swap space, which depends on the
  12899. file system mounted at @file{/btrfs}. Note how we use Guile's filter to
  12900. select the file system in an elegant fashion!
  12901. @node User Accounts
  12902. @section User Accounts
  12903. @cindex users
  12904. @cindex accounts
  12905. @cindex user accounts
  12906. User accounts and groups are entirely managed through the
  12907. @code{operating-system} declaration. They are specified with the
  12908. @code{user-account} and @code{user-group} forms:
  12909. @lisp
  12910. (user-account
  12911. (name "alice")
  12912. (group "users")
  12913. (supplementary-groups '("wheel" ;allow use of sudo, etc.
  12914. "audio" ;sound card
  12915. "video" ;video devices such as webcams
  12916. "cdrom")) ;the good ol' CD-ROM
  12917. (comment "Bob's sister"))
  12918. @end lisp
  12919. Here's a user account that uses a different shell and a custom home
  12920. directory (the default would be @file{"/home/bob"}):
  12921. @lisp
  12922. (user-account
  12923. (name "bob")
  12924. (group "users")
  12925. (comment "Alice's bro")
  12926. (shell (file-append zsh "/bin/zsh"))
  12927. (home-directory "/home/robert"))
  12928. @end lisp
  12929. When booting or upon completion of @command{guix system reconfigure},
  12930. the system ensures that only the user accounts and groups specified in
  12931. the @code{operating-system} declaration exist, and with the specified
  12932. properties. Thus, account or group creations or modifications made by
  12933. directly invoking commands such as @command{useradd} are lost upon
  12934. reconfiguration or reboot. This ensures that the system remains exactly
  12935. as declared.
  12936. @deftp {Data Type} user-account
  12937. Objects of this type represent user accounts. The following members may
  12938. be specified:
  12939. @table @asis
  12940. @item @code{name}
  12941. The name of the user account.
  12942. @item @code{group}
  12943. @cindex groups
  12944. This is the name (a string) or identifier (a number) of the user group
  12945. this account belongs to.
  12946. @item @code{supplementary-groups} (default: @code{'()})
  12947. Optionally, this can be defined as a list of group names that this
  12948. account belongs to.
  12949. @item @code{uid} (default: @code{#f})
  12950. This is the user ID for this account (a number), or @code{#f}. In the
  12951. latter case, a number is automatically chosen by the system when the
  12952. account is created.
  12953. @item @code{comment} (default: @code{""})
  12954. A comment about the account, such as the account owner's full name.
  12955. Note that, for non-system accounts, users are free to change their real
  12956. name as it appears in @file{/etc/passwd} using the @command{chfn}
  12957. command. When they do, their choice prevails over the system
  12958. administrator's choice; reconfiguring does @emph{not} change their name.
  12959. @item @code{home-directory}
  12960. This is the name of the home directory for the account.
  12961. @item @code{create-home-directory?} (default: @code{#t})
  12962. Indicates whether the home directory of this account should be created
  12963. if it does not exist yet.
  12964. @item @code{shell} (default: Bash)
  12965. This is a G-expression denoting the file name of a program to be used as
  12966. the shell (@pxref{G-Expressions}). For example, you would refer to the
  12967. Bash executable like this:
  12968. @lisp
  12969. (file-append bash "/bin/bash")
  12970. @end lisp
  12971. @noindent
  12972. ... and to the Zsh executable like that:
  12973. @lisp
  12974. (file-append zsh "/bin/zsh")
  12975. @end lisp
  12976. @item @code{system?} (default: @code{#f})
  12977. This Boolean value indicates whether the account is a ``system''
  12978. account. System accounts are sometimes treated specially; for instance,
  12979. graphical login managers do not list them.
  12980. @anchor{user-account-password}
  12981. @cindex password, for user accounts
  12982. @item @code{password} (default: @code{#f})
  12983. You would normally leave this field to @code{#f}, initialize user
  12984. passwords as @code{root} with the @command{passwd} command, and then let
  12985. users change it with @command{passwd}. Passwords set with
  12986. @command{passwd} are of course preserved across reboot and
  12987. reconfiguration.
  12988. If you @emph{do} want to set an initial password for an account, then
  12989. this field must contain the encrypted password, as a string. You can use the
  12990. @code{crypt} procedure for this purpose:
  12991. @lisp
  12992. (user-account
  12993. (name "charlie")
  12994. (group "users")
  12995. ;; Specify a SHA-512-hashed initial password.
  12996. (password (crypt "InitialPassword!" "$6$abc")))
  12997. @end lisp
  12998. @quotation Note
  12999. The hash of this initial password will be available in a file in
  13000. @file{/gnu/store}, readable by all the users, so this method must be used with
  13001. care.
  13002. @end quotation
  13003. @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
  13004. more information on password encryption, and @ref{Encryption,,, guile, GNU
  13005. Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
  13006. @end table
  13007. @end deftp
  13008. @cindex groups
  13009. User group declarations are even simpler:
  13010. @lisp
  13011. (user-group (name "students"))
  13012. @end lisp
  13013. @deftp {Data Type} user-group
  13014. This type is for, well, user groups. There are just a few fields:
  13015. @table @asis
  13016. @item @code{name}
  13017. The name of the group.
  13018. @item @code{id} (default: @code{#f})
  13019. The group identifier (a number). If @code{#f}, a new number is
  13020. automatically allocated when the group is created.
  13021. @item @code{system?} (default: @code{#f})
  13022. This Boolean value indicates whether the group is a ``system'' group.
  13023. System groups have low numerical IDs.
  13024. @item @code{password} (default: @code{#f})
  13025. What, user groups can have a password? Well, apparently yes. Unless
  13026. @code{#f}, this field specifies the password of the group.
  13027. @end table
  13028. @end deftp
  13029. For convenience, a variable lists all the basic user groups one may
  13030. expect:
  13031. @defvr {Scheme Variable} %base-groups
  13032. This is the list of basic user groups that users and/or packages expect
  13033. to be present on the system. This includes groups such as ``root'',
  13034. ``wheel'', and ``users'', as well as groups used to control access to
  13035. specific devices such as ``audio'', ``disk'', and ``cdrom''.
  13036. @end defvr
  13037. @defvr {Scheme Variable} %base-user-accounts
  13038. This is the list of basic system accounts that programs may expect to
  13039. find on a GNU/Linux system, such as the ``nobody'' account.
  13040. Note that the ``root'' account is not included here. It is a
  13041. special-case and is automatically added whether or not it is specified.
  13042. @end defvr
  13043. @node Keyboard Layout
  13044. @section Keyboard Layout
  13045. @cindex keyboard layout
  13046. @cindex keymap
  13047. To specify what each key of your keyboard does, you need to tell the operating
  13048. system what @dfn{keyboard layout} you want to use. The default, when nothing
  13049. is specified, is the US English QWERTY layout for 105-key PC keyboards.
  13050. However, German speakers will usually prefer the German QWERTZ layout, French
  13051. speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
  13052. or bépo, and they might even want to further customize the effect of some of
  13053. the keys. This section explains how to get that done.
  13054. @cindex keyboard layout, definition
  13055. There are three components that will want to know about your keyboard layout:
  13056. @itemize
  13057. @item
  13058. The @emph{bootloader} may want to know what keyboard layout you want to use
  13059. (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
  13060. you want, for instance, to make sure that you can type the passphrase of your
  13061. encrypted root partition using the right layout.
  13062. @item
  13063. The @emph{operating system kernel}, Linux, will need that so that the console
  13064. is properly configured (@pxref{operating-system Reference,
  13065. @code{keyboard-layout}}).
  13066. @item
  13067. The @emph{graphical display server}, usually Xorg, also has its own idea of
  13068. the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
  13069. @end itemize
  13070. Guix allows you to configure all three separately but, fortunately, it allows
  13071. you to share the same keyboard layout for all three components.
  13072. @cindex XKB, keyboard layouts
  13073. Keyboard layouts are represented by records created by the
  13074. @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
  13075. the X Keyboard extension (XKB), each layout has four attributes: a name (often
  13076. a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
  13077. optional variant name, an optional keyboard model name, and a possibly empty
  13078. list of additional options. In most cases the layout name is all you care
  13079. about.
  13080. @deffn {Scheme Procedure} keyboard-layout @var{name} [@var{variant}] @
  13081. [#:model] [#:options '()]
  13082. Return a new keyboard layout with the given @var{name} and @var{variant}.
  13083. @var{name} must be a string such as @code{"fr"}; @var{variant} must be a
  13084. string such as @code{"bepo"} or @code{"nodeadkeys"}. See the
  13085. @code{xkeyboard-config} package for valid options.
  13086. @end deffn
  13087. Here are a few examples:
  13088. @lisp
  13089. ;; The German QWERTZ layout. Here we assume a standard
  13090. ;; "pc105" keyboard model.
  13091. (keyboard-layout "de")
  13092. ;; The bépo variant of the French layout.
  13093. (keyboard-layout "fr" "bepo")
  13094. ;; The Catalan layout.
  13095. (keyboard-layout "es" "cat")
  13096. ;; Arabic layout with "Alt-Shift" to switch to US layout.
  13097. (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
  13098. ;; The Latin American Spanish layout. In addition, the
  13099. ;; "Caps Lock" key is used as an additional "Ctrl" key,
  13100. ;; and the "Menu" key is used as a "Compose" key to enter
  13101. ;; accented letters.
  13102. (keyboard-layout "latam"
  13103. #:options '("ctrl:nocaps" "compose:menu"))
  13104. ;; The Russian layout for a ThinkPad keyboard.
  13105. (keyboard-layout "ru" #:model "thinkpad")
  13106. ;; The "US international" layout, which is the US layout plus
  13107. ;; dead keys to enter accented characters. This is for an
  13108. ;; Apple MacBook keyboard.
  13109. (keyboard-layout "us" "intl" #:model "macbook78")
  13110. @end lisp
  13111. See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
  13112. for a complete list of supported layouts, variants, and models.
  13113. @cindex keyboard layout, configuration
  13114. Let's say you want your system to use the Turkish keyboard layout throughout
  13115. your system---bootloader, console, and Xorg. Here's what your system
  13116. configuration would look like:
  13117. @findex set-xorg-configuration
  13118. @lisp
  13119. ;; Using the Turkish layout for the bootloader, the console,
  13120. ;; and for Xorg.
  13121. (operating-system
  13122. ;; ...
  13123. (keyboard-layout (keyboard-layout "tr")) ;for the console
  13124. (bootloader (bootloader-configuration
  13125. (bootloader grub-efi-bootloader)
  13126. (targets '("/boot/efi"))
  13127. (keyboard-layout keyboard-layout))) ;for GRUB
  13128. (services (cons (set-xorg-configuration
  13129. (xorg-configuration ;for Xorg
  13130. (keyboard-layout keyboard-layout)))
  13131. %desktop-services)))
  13132. @end lisp
  13133. In the example above, for GRUB and for Xorg, we just refer to the
  13134. @code{keyboard-layout} field defined above, but we could just as well refer to
  13135. a different layout. The @code{set-xorg-configuration} procedure communicates
  13136. the desired Xorg configuration to the graphical log-in manager, by default
  13137. GDM.
  13138. We've discussed how to specify the @emph{default} keyboard layout of your
  13139. system when it starts, but you can also adjust it at run time:
  13140. @itemize
  13141. @item
  13142. If you're using GNOME, its settings panel has a ``Region & Language'' entry
  13143. where you can select one or more keyboard layouts.
  13144. @item
  13145. Under Xorg, the @command{setxkbmap} command (from the same-named package)
  13146. allows you to change the current layout. For example, this is how you would
  13147. change the layout to US Dvorak:
  13148. @example
  13149. setxkbmap us dvorak
  13150. @end example
  13151. @item
  13152. The @code{loadkeys} command changes the keyboard layout in effect in the Linux
  13153. console. However, note that @code{loadkeys} does @emph{not} use the XKB
  13154. keyboard layout categorization described above. The command below loads the
  13155. French bépo layout:
  13156. @example
  13157. loadkeys fr-bepo
  13158. @end example
  13159. @end itemize
  13160. @node Locales
  13161. @section Locales
  13162. @cindex locale
  13163. A @dfn{locale} defines cultural conventions for a particular language
  13164. and region of the world (@pxref{Locales,,, libc, The GNU C Library
  13165. Reference Manual}). Each locale has a name that typically has the form
  13166. @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
  13167. @code{fr_LU.utf8} designates the locale for the French language, with
  13168. cultural conventions from Luxembourg, and using the UTF-8 encoding.
  13169. @cindex locale definition
  13170. Usually, you will want to specify the default locale for the machine
  13171. using the @code{locale} field of the @code{operating-system} declaration
  13172. (@pxref{operating-system Reference, @code{locale}}).
  13173. The selected locale is automatically added to the @dfn{locale
  13174. definitions} known to the system if needed, with its codeset inferred
  13175. from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
  13176. @code{UTF-8} codeset. Additional locale definitions can be specified in
  13177. the @code{locale-definitions} slot of @code{operating-system}---this is
  13178. useful, for instance, if the codeset could not be inferred from the
  13179. locale name. The default set of locale definitions includes some widely
  13180. used locales, but not all the available locales, in order to save space.
  13181. For instance, to add the North Frisian locale for Germany, the value of
  13182. that field may be:
  13183. @lisp
  13184. (cons (locale-definition
  13185. (name "fy_DE.utf8") (source "fy_DE"))
  13186. %default-locale-definitions)
  13187. @end lisp
  13188. Likewise, to save space, one might want @code{locale-definitions} to
  13189. list only the locales that are actually used, as in:
  13190. @lisp
  13191. (list (locale-definition
  13192. (name "ja_JP.eucjp") (source "ja_JP")
  13193. (charset "EUC-JP")))
  13194. @end lisp
  13195. @vindex LOCPATH
  13196. The compiled locale definitions are available at
  13197. @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
  13198. version, which is the default location where the GNU@tie{}libc provided
  13199. by Guix looks for locale data. This can be overridden using the
  13200. @env{LOCPATH} environment variable (@pxref{locales-and-locpath,
  13201. @env{LOCPATH} and locale packages}).
  13202. The @code{locale-definition} form is provided by the @code{(gnu system
  13203. locale)} module. Details are given below.
  13204. @deftp {Data Type} locale-definition
  13205. This is the data type of a locale definition.
  13206. @table @asis
  13207. @item @code{name}
  13208. The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
  13209. Reference Manual}, for more information on locale names.
  13210. @item @code{source}
  13211. The name of the source for that locale. This is typically the
  13212. @code{@var{language}_@var{territory}} part of the locale name.
  13213. @item @code{charset} (default: @code{"UTF-8"})
  13214. The ``character set'' or ``code set'' for that locale,
  13215. @uref{https://www.iana.org/assignments/character-sets, as defined by
  13216. IANA}.
  13217. @end table
  13218. @end deftp
  13219. @defvr {Scheme Variable} %default-locale-definitions
  13220. A list of commonly used UTF-8 locales, used as the default
  13221. value of the @code{locale-definitions} field of @code{operating-system}
  13222. declarations.
  13223. @cindex locale name
  13224. @cindex normalized codeset in locale names
  13225. These locale definitions use the @dfn{normalized codeset} for the part
  13226. that follows the dot in the name (@pxref{Using gettextized software,
  13227. normalized codeset,, libc, The GNU C Library Reference Manual}). So for
  13228. instance it has @code{uk_UA.utf8} but @emph{not}, say,
  13229. @code{uk_UA.UTF-8}.
  13230. @end defvr
  13231. @subsection Locale Data Compatibility Considerations
  13232. @cindex incompatibility, of locale data
  13233. @code{operating-system} declarations provide a @code{locale-libcs} field
  13234. to specify the GNU@tie{}libc packages that are used to compile locale
  13235. declarations (@pxref{operating-system Reference}). ``Why would I
  13236. care?'', you may ask. Well, it turns out that the binary format of
  13237. locale data is occasionally incompatible from one libc version to
  13238. another.
  13239. @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
  13240. @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
  13241. For instance, a program linked against libc version 2.21 is unable to
  13242. read locale data produced with libc 2.22; worse, that program
  13243. @emph{aborts} instead of simply ignoring the incompatible locale
  13244. data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
  13245. the incompatible locale data, which is already an improvement.}.
  13246. Similarly, a program linked against libc 2.22 can read most, but not
  13247. all, of the locale data from libc 2.21 (specifically, @env{LC_COLLATE}
  13248. data is incompatible); thus calls to @code{setlocale} may fail, but
  13249. programs will not abort.
  13250. The ``problem'' with Guix is that users have a lot of freedom: They can
  13251. choose whether and when to upgrade software in their profiles, and might
  13252. be using a libc version different from the one the system administrator
  13253. used to build the system-wide locale data.
  13254. Fortunately, unprivileged users can also install their own locale data
  13255. and define @env{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
  13256. @env{GUIX_LOCPATH} and locale packages}).
  13257. Still, it is best if the system-wide locale data at
  13258. @file{/run/current-system/locale} is built for all the libc versions
  13259. actually in use on the system, so that all the programs can access
  13260. it---this is especially crucial on a multi-user system. To do that, the
  13261. administrator can specify several libc packages in the
  13262. @code{locale-libcs} field of @code{operating-system}:
  13263. @lisp
  13264. (use-package-modules base)
  13265. (operating-system
  13266. ;; @dots{}
  13267. (locale-libcs (list glibc-2.21 (canonical-package glibc))))
  13268. @end lisp
  13269. This example would lead to a system containing locale definitions for
  13270. both libc 2.21 and the current version of libc in
  13271. @file{/run/current-system/locale}.
  13272. @node Services
  13273. @section Services
  13274. @cindex system services
  13275. An important part of preparing an @code{operating-system} declaration is
  13276. listing @dfn{system services} and their configuration (@pxref{Using the
  13277. Configuration System}). System services are typically daemons launched
  13278. when the system boots, or other actions needed at that time---e.g.,
  13279. configuring network access.
  13280. Guix has a broad definition of ``service'' (@pxref{Service
  13281. Composition}), but many services are managed by the GNU@tie{}Shepherd
  13282. (@pxref{Shepherd Services}). On a running system, the @command{herd}
  13283. command allows you to list the available services, show their status,
  13284. start and stop them, or do other specific operations (@pxref{Jump
  13285. Start,,, shepherd, The GNU Shepherd Manual}). For example:
  13286. @example
  13287. # herd status
  13288. @end example
  13289. The above command, run as @code{root}, lists the currently defined
  13290. services. The @command{herd doc} command shows a synopsis of the given
  13291. service and its associated actions:
  13292. @example
  13293. # herd doc nscd
  13294. Run libc's name service cache daemon (nscd).
  13295. # herd doc nscd action invalidate
  13296. invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
  13297. @end example
  13298. The @command{start}, @command{stop}, and @command{restart} sub-commands
  13299. have the effect you would expect. For instance, the commands below stop
  13300. the nscd service and restart the Xorg display server:
  13301. @example
  13302. # herd stop nscd
  13303. Service nscd has been stopped.
  13304. # herd restart xorg-server
  13305. Service xorg-server has been stopped.
  13306. Service xorg-server has been started.
  13307. @end example
  13308. The following sections document the available services, starting with
  13309. the core services, that may be used in an @code{operating-system}
  13310. declaration.
  13311. @menu
  13312. * Base Services:: Essential system services.
  13313. * Scheduled Job Execution:: The mcron service.
  13314. * Log Rotation:: The rottlog service.
  13315. * Networking Setup:: Setting up network interfaces.
  13316. * Networking Services:: Firewall, SSH daemon, etc.
  13317. * Unattended Upgrades:: Automated system upgrades.
  13318. * X Window:: Graphical display.
  13319. * Printing Services:: Local and remote printer support.
  13320. * Desktop Services:: D-Bus and desktop services.
  13321. * Sound Services:: ALSA and Pulseaudio services.
  13322. * Database Services:: SQL databases, key-value stores, etc.
  13323. * Mail Services:: IMAP, POP3, SMTP, and all that.
  13324. * Messaging Services:: Messaging services.
  13325. * Telephony Services:: Telephony services.
  13326. * File-Sharing Services:: File-sharing services.
  13327. * Monitoring Services:: Monitoring services.
  13328. * Kerberos Services:: Kerberos services.
  13329. * LDAP Services:: LDAP services.
  13330. * Web Services:: Web servers.
  13331. * Certificate Services:: TLS certificates via Let's Encrypt.
  13332. * DNS Services:: DNS daemons.
  13333. * VPN Services:: VPN daemons.
  13334. * Network File System:: NFS related services.
  13335. * Continuous Integration:: Cuirass and Laminar services.
  13336. * Power Management Services:: Extending battery life.
  13337. * Audio Services:: The MPD.
  13338. * Virtualization Services:: Virtualization services.
  13339. * Version Control Services:: Providing remote access to Git repositories.
  13340. * Game Services:: Game servers.
  13341. * PAM Mount Service:: Service to mount volumes when logging in.
  13342. * Guix Services:: Services relating specifically to Guix.
  13343. * Linux Services:: Services tied to the Linux kernel.
  13344. * Hurd Services:: Services specific for a Hurd System.
  13345. * Miscellaneous Services:: Other services.
  13346. @end menu
  13347. @node Base Services
  13348. @subsection Base Services
  13349. The @code{(gnu services base)} module provides definitions for the basic
  13350. services that one expects from the system. The services exported by
  13351. this module are listed below.
  13352. @defvr {Scheme Variable} %base-services
  13353. This variable contains a list of basic services (@pxref{Service Types
  13354. and Services}, for more information on service objects) one would
  13355. expect from the system: a login service (mingetty) on each tty, syslogd,
  13356. the libc name service cache daemon (nscd), the udev device manager, and
  13357. more.
  13358. This is the default value of the @code{services} field of
  13359. @code{operating-system} declarations. Usually, when customizing a
  13360. system, you will want to append services to @code{%base-services}, like
  13361. this:
  13362. @lisp
  13363. (append (list (service avahi-service-type)
  13364. (service openssh-service-type))
  13365. %base-services)
  13366. @end lisp
  13367. @end defvr
  13368. @defvr {Scheme Variable} special-files-service-type
  13369. This is the service that sets up ``special files'' such as
  13370. @file{/bin/sh}; an instance of it is part of @code{%base-services}.
  13371. The value associated with @code{special-files-service-type} services
  13372. must be a list of tuples where the first element is the ``special file''
  13373. and the second element is its target. By default it is:
  13374. @cindex @file{/bin/sh}
  13375. @cindex @file{sh}, in @file{/bin}
  13376. @lisp
  13377. `(("/bin/sh" ,(file-append bash "/bin/sh")))
  13378. @end lisp
  13379. @cindex @file{/usr/bin/env}
  13380. @cindex @file{env}, in @file{/usr/bin}
  13381. If you want to add, say, @code{/usr/bin/env} to your system, you can
  13382. change it to:
  13383. @lisp
  13384. `(("/bin/sh" ,(file-append bash "/bin/sh"))
  13385. ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
  13386. @end lisp
  13387. Since this is part of @code{%base-services}, you can use
  13388. @code{modify-services} to customize the set of special files
  13389. (@pxref{Service Reference, @code{modify-services}}). But the simple way
  13390. to add a special file is @i{via} the @code{extra-special-file} procedure
  13391. (see below).
  13392. @end defvr
  13393. @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
  13394. Use @var{target} as the ``special file'' @var{file}.
  13395. For example, adding the following lines to the @code{services} field of
  13396. your operating system declaration leads to a @file{/usr/bin/env}
  13397. symlink:
  13398. @lisp
  13399. (extra-special-file "/usr/bin/env"
  13400. (file-append coreutils "/bin/env"))
  13401. @end lisp
  13402. @end deffn
  13403. @deffn {Scheme Procedure} host-name-service @var{name}
  13404. Return a service that sets the host name to @var{name}.
  13405. @end deffn
  13406. @defvr {Scheme Variable} console-font-service-type
  13407. Install the given fonts on the specified ttys (fonts are per
  13408. virtual console on the kernel Linux). The value of this service is a list of
  13409. tty/font pairs. The font can be the name of a font provided by the @code{kbd}
  13410. package or any valid argument to @command{setfont}, as in this example:
  13411. @lisp
  13412. `(("tty1" . "LatGrkCyr-8x16")
  13413. ("tty2" . ,(file-append
  13414. font-tamzen
  13415. "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
  13416. ("tty3" . ,(file-append
  13417. font-terminus
  13418. "/share/consolefonts/ter-132n"))) ; for HDPI
  13419. @end lisp
  13420. @end defvr
  13421. @deffn {Scheme Procedure} login-service @var{config}
  13422. Return a service to run login according to @var{config}, a
  13423. @code{<login-configuration>} object, which specifies the message of the day,
  13424. among other things.
  13425. @end deffn
  13426. @deftp {Data Type} login-configuration
  13427. This is the data type representing the configuration of login.
  13428. @table @asis
  13429. @item @code{motd}
  13430. @cindex message of the day
  13431. A file-like object containing the ``message of the day''.
  13432. @item @code{allow-empty-passwords?} (default: @code{#t})
  13433. Allow empty passwords by default so that first-time users can log in when
  13434. the 'root' account has just been created.
  13435. @end table
  13436. @end deftp
  13437. @deffn {Scheme Procedure} mingetty-service @var{config}
  13438. Return a service to run mingetty according to @var{config}, a
  13439. @code{<mingetty-configuration>} object, which specifies the tty to run, among
  13440. other things.
  13441. @end deffn
  13442. @deftp {Data Type} mingetty-configuration
  13443. This is the data type representing the configuration of Mingetty, which
  13444. provides the default implementation of virtual console log-in.
  13445. @table @asis
  13446. @item @code{tty}
  13447. The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
  13448. @item @code{auto-login} (default: @code{#f})
  13449. When true, this field must be a string denoting the user name under
  13450. which the system automatically logs in. When it is @code{#f}, a
  13451. user name and password must be entered to log in.
  13452. @item @code{login-program} (default: @code{#f})
  13453. This must be either @code{#f}, in which case the default log-in program
  13454. is used (@command{login} from the Shadow tool suite), or a gexp denoting
  13455. the name of the log-in program.
  13456. @item @code{login-pause?} (default: @code{#f})
  13457. When set to @code{#t} in conjunction with @var{auto-login}, the user
  13458. will have to press a key before the log-in shell is launched.
  13459. @item @code{clear-on-logout?} (default: @code{#t})
  13460. When set to @code{#t}, the screen will be cleared after logout.
  13461. @item @code{mingetty} (default: @var{mingetty})
  13462. The Mingetty package to use.
  13463. @end table
  13464. @end deftp
  13465. @deffn {Scheme Procedure} agetty-service @var{config}
  13466. Return a service to run agetty according to @var{config}, an
  13467. @code{<agetty-configuration>} object, which specifies the tty to run,
  13468. among other things.
  13469. @end deffn
  13470. @deftp {Data Type} agetty-configuration
  13471. This is the data type representing the configuration of agetty, which
  13472. implements virtual and serial console log-in. See the @code{agetty(8)}
  13473. man page for more information.
  13474. @table @asis
  13475. @item @code{tty}
  13476. The name of the console this agetty runs on, as a string---e.g.,
  13477. @code{"ttyS0"}. This argument is optional, it will default to
  13478. a reasonable default serial port used by the kernel Linux.
  13479. For this, if there is a value for an option @code{agetty.tty} in the kernel
  13480. command line, agetty will extract the device name of the serial port
  13481. from it and use that.
  13482. If not and if there is a value for an option @code{console} with a tty in
  13483. the Linux command line, agetty will extract the device name of the
  13484. serial port from it and use that.
  13485. In both cases, agetty will leave the other serial device settings
  13486. (baud rate etc.)@: alone---in the hope that Linux pinned them to the
  13487. correct values.
  13488. @item @code{baud-rate} (default: @code{#f})
  13489. A string containing a comma-separated list of one or more baud rates, in
  13490. descending order.
  13491. @item @code{term} (default: @code{#f})
  13492. A string containing the value used for the @env{TERM} environment
  13493. variable.
  13494. @item @code{eight-bits?} (default: @code{#f})
  13495. When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
  13496. disabled.
  13497. @item @code{auto-login} (default: @code{#f})
  13498. When passed a login name, as a string, the specified user will be logged
  13499. in automatically without prompting for their login name or password.
  13500. @item @code{no-reset?} (default: @code{#f})
  13501. When @code{#t}, don't reset terminal cflags (control modes).
  13502. @item @code{host} (default: @code{#f})
  13503. This accepts a string containing the ``login_host'', which will be written
  13504. into the @file{/var/run/utmpx} file.
  13505. @item @code{remote?} (default: @code{#f})
  13506. When set to @code{#t} in conjunction with @var{host}, this will add an
  13507. @code{-r} fakehost option to the command line of the login program
  13508. specified in @var{login-program}.
  13509. @item @code{flow-control?} (default: @code{#f})
  13510. When set to @code{#t}, enable hardware (RTS/CTS) flow control.
  13511. @item @code{no-issue?} (default: @code{#f})
  13512. When set to @code{#t}, the contents of the @file{/etc/issue} file will
  13513. not be displayed before presenting the login prompt.
  13514. @item @code{init-string} (default: @code{#f})
  13515. This accepts a string that will be sent to the tty or modem before
  13516. sending anything else. It can be used to initialize a modem.
  13517. @item @code{no-clear?} (default: @code{#f})
  13518. When set to @code{#t}, agetty will not clear the screen before showing
  13519. the login prompt.
  13520. @item @code{login-program} (default: (file-append shadow "/bin/login"))
  13521. This must be either a gexp denoting the name of a log-in program, or
  13522. unset, in which case the default value is the @command{login} from the
  13523. Shadow tool suite.
  13524. @item @code{local-line} (default: @code{#f})
  13525. Control the CLOCAL line flag. This accepts one of three symbols as
  13526. arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
  13527. the default value chosen by agetty is @code{'auto}.
  13528. @item @code{extract-baud?} (default: @code{#f})
  13529. When set to @code{#t}, instruct agetty to try to extract the baud rate
  13530. from the status messages produced by certain types of modems.
  13531. @item @code{skip-login?} (default: @code{#f})
  13532. When set to @code{#t}, do not prompt the user for a login name. This
  13533. can be used with @var{login-program} field to use non-standard login
  13534. systems.
  13535. @item @code{no-newline?} (default: @code{#f})
  13536. When set to @code{#t}, do not print a newline before printing the
  13537. @file{/etc/issue} file.
  13538. @c Is this dangerous only when used with login-program, or always?
  13539. @item @code{login-options} (default: @code{#f})
  13540. This option accepts a string containing options that are passed to the
  13541. login program. When used with the @var{login-program}, be aware that a
  13542. malicious user could try to enter a login name containing embedded
  13543. options that could be parsed by the login program.
  13544. @item @code{login-pause} (default: @code{#f})
  13545. When set to @code{#t}, wait for any key before showing the login prompt.
  13546. This can be used in conjunction with @var{auto-login} to save memory by
  13547. lazily spawning shells.
  13548. @item @code{chroot} (default: @code{#f})
  13549. Change root to the specified directory. This option accepts a directory
  13550. path as a string.
  13551. @item @code{hangup?} (default: @code{#f})
  13552. Use the Linux system call @code{vhangup} to do a virtual hangup of the
  13553. specified terminal.
  13554. @item @code{keep-baud?} (default: @code{#f})
  13555. When set to @code{#t}, try to keep the existing baud rate. The baud
  13556. rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
  13557. character.
  13558. @item @code{timeout} (default: @code{#f})
  13559. When set to an integer value, terminate if no user name could be read
  13560. within @var{timeout} seconds.
  13561. @item @code{detect-case?} (default: @code{#f})
  13562. When set to @code{#t}, turn on support for detecting an uppercase-only
  13563. terminal. This setting will detect a login name containing only
  13564. uppercase letters as indicating an uppercase-only terminal and turn on
  13565. some upper-to-lower case conversions. Note that this will not support
  13566. Unicode characters.
  13567. @item @code{wait-cr?} (default: @code{#f})
  13568. When set to @code{#t}, wait for the user or modem to send a
  13569. carriage-return or linefeed character before displaying
  13570. @file{/etc/issue} or login prompt. This is typically used with the
  13571. @var{init-string} option.
  13572. @item @code{no-hints?} (default: @code{#f})
  13573. When set to @code{#t}, do not print hints about Num, Caps, and Scroll
  13574. locks.
  13575. @item @code{no-hostname?} (default: @code{#f})
  13576. By default, the hostname is printed. When this option is set to
  13577. @code{#t}, no hostname will be shown at all.
  13578. @item @code{long-hostname?} (default: @code{#f})
  13579. By default, the hostname is only printed until the first dot. When this
  13580. option is set to @code{#t}, the fully qualified hostname by
  13581. @code{gethostname} or @code{getaddrinfo} is shown.
  13582. @item @code{erase-characters} (default: @code{#f})
  13583. This option accepts a string of additional characters that should be
  13584. interpreted as backspace when the user types their login name.
  13585. @item @code{kill-characters} (default: @code{#f})
  13586. This option accepts a string that should be interpreted to mean ``ignore
  13587. all previous characters'' (also called a ``kill'' character) when the user
  13588. types their login name.
  13589. @item @code{chdir} (default: @code{#f})
  13590. This option accepts, as a string, a directory path that will be changed
  13591. to before login.
  13592. @item @code{delay} (default: @code{#f})
  13593. This options accepts, as an integer, the number of seconds to sleep
  13594. before opening the tty and displaying the login prompt.
  13595. @item @code{nice} (default: @code{#f})
  13596. This option accepts, as an integer, the nice value with which to run the
  13597. @command{login} program.
  13598. @item @code{extra-options} (default: @code{'()})
  13599. This option provides an ``escape hatch'' for the user to provide arbitrary
  13600. command-line arguments to @command{agetty} as a list of strings.
  13601. @item @code{shepherd-requirement} (default: @code{'()})
  13602. The option can be used to provides extra shepherd requirements (for example
  13603. @code{'syslogd}) to the respective @code{'term-}* shepherd service.
  13604. @end table
  13605. @end deftp
  13606. @deffn {Scheme Procedure} kmscon-service-type @var{config}
  13607. Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
  13608. according to @var{config}, a @code{<kmscon-configuration>} object, which
  13609. specifies the tty to run, among other things.
  13610. @end deffn
  13611. @deftp {Data Type} kmscon-configuration
  13612. This is the data type representing the configuration of Kmscon, which
  13613. implements virtual console log-in.
  13614. @table @asis
  13615. @item @code{virtual-terminal}
  13616. The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
  13617. @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
  13618. A gexp denoting the name of the log-in program. The default log-in program is
  13619. @command{login} from the Shadow tool suite.
  13620. @item @code{login-arguments} (default: @code{'("-p")})
  13621. A list of arguments to pass to @command{login}.
  13622. @item @code{auto-login} (default: @code{#f})
  13623. When passed a login name, as a string, the specified user will be logged
  13624. in automatically without prompting for their login name or password.
  13625. @item @code{hardware-acceleration?} (default: #f)
  13626. Whether to use hardware acceleration.
  13627. @item @code{font-engine} (default: @code{"pango"})
  13628. Font engine used in Kmscon.
  13629. @item @code{font-size} (default: @code{12})
  13630. Font size used in Kmscon.
  13631. @item @code{keyboard-layout} (default: @code{#f})
  13632. If this is @code{#f}, Kmscon uses the default keyboard layout---usually US
  13633. English (``qwerty'') for a 105-key PC keyboard.
  13634. Otherwise this must be a @code{keyboard-layout} object specifying the
  13635. keyboard layout. @xref{Keyboard Layout}, for more information on how to
  13636. specify the keyboard layout.
  13637. @item @code{kmscon} (default: @var{kmscon})
  13638. The Kmscon package to use.
  13639. @end table
  13640. @end deftp
  13641. @cindex name service cache daemon
  13642. @cindex nscd
  13643. @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
  13644. [#:name-services '()]
  13645. Return a service that runs the libc name service cache daemon (nscd) with the
  13646. given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
  13647. Service Switch}, for an example.
  13648. For convenience, the Shepherd service for nscd provides the following actions:
  13649. @table @code
  13650. @item invalidate
  13651. @cindex cache invalidation, nscd
  13652. @cindex nscd, cache invalidation
  13653. This invalidate the given cache. For instance, running:
  13654. @example
  13655. herd invalidate nscd hosts
  13656. @end example
  13657. @noindent
  13658. invalidates the host name lookup cache of nscd.
  13659. @item statistics
  13660. Running @command{herd statistics nscd} displays information about nscd usage
  13661. and caches.
  13662. @end table
  13663. @end deffn
  13664. @defvr {Scheme Variable} %nscd-default-configuration
  13665. This is the default @code{<nscd-configuration>} value (see below) used
  13666. by @code{nscd-service}. It uses the caches defined by
  13667. @code{%nscd-default-caches}; see below.
  13668. @end defvr
  13669. @deftp {Data Type} nscd-configuration
  13670. This is the data type representing the name service cache daemon (nscd)
  13671. configuration.
  13672. @table @asis
  13673. @item @code{name-services} (default: @code{'()})
  13674. List of packages denoting @dfn{name services} that must be visible to
  13675. the nscd---e.g., @code{(list @var{nss-mdns})}.
  13676. @item @code{glibc} (default: @var{glibc})
  13677. Package object denoting the GNU C Library providing the @command{nscd}
  13678. command.
  13679. @item @code{log-file} (default: @code{"/var/log/nscd.log"})
  13680. Name of the nscd log file. This is where debugging output goes when
  13681. @code{debug-level} is strictly positive.
  13682. @item @code{debug-level} (default: @code{0})
  13683. Integer denoting the debugging levels. Higher numbers mean that more
  13684. debugging output is logged.
  13685. @item @code{caches} (default: @code{%nscd-default-caches})
  13686. List of @code{<nscd-cache>} objects denoting things to be cached; see
  13687. below.
  13688. @end table
  13689. @end deftp
  13690. @deftp {Data Type} nscd-cache
  13691. Data type representing a cache database of nscd and its parameters.
  13692. @table @asis
  13693. @item @code{database}
  13694. This is a symbol representing the name of the database to be cached.
  13695. Valid values are @code{passwd}, @code{group}, @code{hosts}, and
  13696. @code{services}, which designate the corresponding NSS database
  13697. (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
  13698. @item @code{positive-time-to-live}
  13699. @itemx @code{negative-time-to-live} (default: @code{20})
  13700. A number representing the number of seconds during which a positive or
  13701. negative lookup result remains in cache.
  13702. @item @code{check-files?} (default: @code{#t})
  13703. Whether to check for updates of the files corresponding to
  13704. @var{database}.
  13705. For instance, when @var{database} is @code{hosts}, setting this flag
  13706. instructs nscd to check for updates in @file{/etc/hosts} and to take
  13707. them into account.
  13708. @item @code{persistent?} (default: @code{#t})
  13709. Whether the cache should be stored persistently on disk.
  13710. @item @code{shared?} (default: @code{#t})
  13711. Whether the cache should be shared among users.
  13712. @item @code{max-database-size} (default: 32@tie{}MiB)
  13713. Maximum size in bytes of the database cache.
  13714. @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
  13715. @c settings, so leave them out.
  13716. @end table
  13717. @end deftp
  13718. @defvr {Scheme Variable} %nscd-default-caches
  13719. List of @code{<nscd-cache>} objects used by default by
  13720. @code{nscd-configuration} (see above).
  13721. It enables persistent and aggressive caching of service and host name
  13722. lookups. The latter provides better host name lookup performance,
  13723. resilience in the face of unreliable name servers, and also better
  13724. privacy---often the result of host name lookups is in local cache, so
  13725. external name servers do not even need to be queried.
  13726. @end defvr
  13727. @anchor{syslog-configuration-type}
  13728. @cindex syslog
  13729. @cindex logging
  13730. @deftp {Data Type} syslog-configuration
  13731. This data type represents the configuration of the syslog daemon.
  13732. @table @asis
  13733. @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
  13734. The syslog daemon to use.
  13735. @item @code{config-file} (default: @code{%default-syslog.conf})
  13736. The syslog configuration file to use.
  13737. @end table
  13738. @end deftp
  13739. @anchor{syslog-service}
  13740. @cindex syslog
  13741. @deffn {Scheme Procedure} syslog-service @var{config}
  13742. Return a service that runs a syslog daemon according to @var{config}.
  13743. @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
  13744. information on the configuration file syntax.
  13745. @end deffn
  13746. @defvr {Scheme Variable} guix-service-type
  13747. This is the type of the service that runs the build daemon,
  13748. @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
  13749. @code{guix-configuration} record as described below.
  13750. @end defvr
  13751. @anchor{guix-configuration-type}
  13752. @deftp {Data Type} guix-configuration
  13753. This data type represents the configuration of the Guix build daemon.
  13754. @xref{Invoking guix-daemon}, for more information.
  13755. @table @asis
  13756. @item @code{guix} (default: @var{guix})
  13757. The Guix package to use.
  13758. @item @code{build-group} (default: @code{"guixbuild"})
  13759. Name of the group for build user accounts.
  13760. @item @code{build-accounts} (default: @code{10})
  13761. Number of build user accounts to create.
  13762. @item @code{authorize-key?} (default: @code{#t})
  13763. @cindex substitutes, authorization thereof
  13764. Whether to authorize the substitute keys listed in
  13765. @code{authorized-keys}---by default that of
  13766. @code{@value{SUBSTITUTE-SERVER-1}} and
  13767. @code{@value{SUBSTITUTE-SERVER-2}}
  13768. (@pxref{Substitutes}).
  13769. When @code{authorize-key?} is true, @file{/etc/guix/acl} cannot be
  13770. changed by invoking @command{guix archive --authorize}. You must
  13771. instead adjust @code{guix-configuration} as you wish and reconfigure the
  13772. system. This ensures that your operating system configuration file is
  13773. self-contained.
  13774. @quotation Note
  13775. When booting or reconfiguring to a system where @code{authorize-key?}
  13776. is true, the existing @file{/etc/guix/acl} file is backed up as
  13777. @file{/etc/guix/acl.bak} if it was determined to be a manually modified
  13778. file. This is to facilitate migration from earlier versions, which
  13779. allowed for in-place modifications to @file{/etc/guix/acl}.
  13780. @end quotation
  13781. @vindex %default-authorized-guix-keys
  13782. @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
  13783. The list of authorized key files for archive imports, as a list of
  13784. string-valued gexps (@pxref{Invoking guix archive}). By default, it
  13785. contains that of @code{@value{SUBSTITUTE-SERVER-1}} and
  13786. @code{@value{SUBSTITUTE-SERVER-2}} (@pxref{Substitutes}). See
  13787. @code{substitute-urls} below for an example on how to change it.
  13788. @item @code{use-substitutes?} (default: @code{#t})
  13789. Whether to use substitutes.
  13790. @item @code{substitute-urls} (default: @code{%default-substitute-urls})
  13791. The list of URLs where to look for substitutes by default.
  13792. Suppose you would like to fetch substitutes from @code{guix.example.org}
  13793. in addition to @code{@value{SUBSTITUTE-SERVER-1}}. You will need to do
  13794. two things: (1) add @code{guix.example.org} to @code{substitute-urls},
  13795. and (2) authorize its signing key, having done appropriate checks
  13796. (@pxref{Substitute Server Authorization}). The configuration below does
  13797. exactly that:
  13798. @lisp
  13799. (guix-configuration
  13800. (substitute-urls
  13801. (append (list "https://guix.example.org")
  13802. %default-substitute-urls))
  13803. (authorized-keys
  13804. (append (list (local-file "./guix.example.org-key.pub"))
  13805. %default-authorized-guix-keys)))
  13806. @end lisp
  13807. This example assumes that the file @file{./guix.example.org-key.pub}
  13808. contains the public key that @code{guix.example.org} uses to sign
  13809. substitutes.
  13810. @item @code{generate-substitute-key?} (default: @code{#t})
  13811. Whether to generate a @dfn{substitute key pair} under
  13812. @file{/etc/guix/signing-key.pub} and @file{/etc/guix/signing-key.sec} if
  13813. there is not already one.
  13814. This key pair is used when exporting store items, for instance with
  13815. @command{guix publish} (@pxref{Invoking guix publish}) or @command{guix
  13816. archive} (@pxref{Invoking guix archive}). Generating a key pair takes a
  13817. few seconds when enough entropy is available and is only done once; you
  13818. might want to turn it off for instance in a virtual machine that does
  13819. not need it and where the extra boot time is a problem.
  13820. @item @code{max-silent-time} (default: @code{0})
  13821. @itemx @code{timeout} (default: @code{0})
  13822. The number of seconds of silence and the number of seconds of activity,
  13823. respectively, after which a build process times out. A value of zero
  13824. disables the timeout.
  13825. @item @code{log-compression} (default: @code{'gzip})
  13826. The type of compression used for build logs---one of @code{gzip},
  13827. @code{bzip2}, or @code{none}.
  13828. @item @code{discover?} (default: @code{#f})
  13829. Whether to discover substitute servers on the local network using mDNS
  13830. and DNS-SD.
  13831. @item @code{extra-options} (default: @code{'()})
  13832. List of extra command-line options for @command{guix-daemon}.
  13833. @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
  13834. File where @command{guix-daemon}'s standard output and standard error
  13835. are written.
  13836. @cindex HTTP proxy, for @code{guix-daemon}
  13837. @cindex proxy, for @code{guix-daemon} HTTP access
  13838. @item @code{http-proxy} (default: @code{#f})
  13839. The URL of the HTTP and HTTPS proxy used for downloading fixed-output
  13840. derivations and substitutes.
  13841. It is also possible to change the daemon's proxy at run time through the
  13842. @code{set-http-proxy} action, which restarts it:
  13843. @example
  13844. herd set-http-proxy guix-daemon http://localhost:8118
  13845. @end example
  13846. To clear the proxy settings, run:
  13847. @example
  13848. herd set-http-proxy guix-daemon
  13849. @end example
  13850. @item @code{tmpdir} (default: @code{#f})
  13851. A directory path where the @command{guix-daemon} will perform builds.
  13852. @end table
  13853. @end deftp
  13854. @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
  13855. Run @var{udev}, which populates the @file{/dev} directory dynamically.
  13856. udev rules can be provided as a list of files through the @var{rules}
  13857. variable. The procedures @code{udev-rule}, @code{udev-rules-service}
  13858. and @code{file->udev-rule} from @code{(gnu services base)} simplify the
  13859. creation of such rule files.
  13860. The @command{herd rules udev} command, as root, returns the name of the
  13861. directory containing all the active udev rules.
  13862. @end deffn
  13863. @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
  13864. Return a udev-rule file named @var{file-name} containing the rules
  13865. defined by the @var{contents} literal.
  13866. In the following example, a rule for a USB device is defined to be
  13867. stored in the file @file{90-usb-thing.rules}. The rule runs a script
  13868. upon detecting a USB device with a given product identifier.
  13869. @lisp
  13870. (define %example-udev-rule
  13871. (udev-rule
  13872. "90-usb-thing.rules"
  13873. (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
  13874. "ATTR@{product@}==\"Example\", "
  13875. "RUN+=\"/path/to/script\"")))
  13876. @end lisp
  13877. @end deffn
  13878. @deffn {Scheme Procedure} udev-rules-service [@var{name} @var{rules}] @
  13879. [#:groups @var{groups}]
  13880. Return a service that extends @code{udev-service-type } with @var{rules}
  13881. and @code{account-service-type} with @var{groups} as system groups.
  13882. This works by creating a singleton service type
  13883. @code{@var{name}-udev-rules}, of which the returned service is an
  13884. instance.
  13885. Here we show how it can be used to extend @code{udev-service-type} with the
  13886. previously defined rule @code{%example-udev-rule}.
  13887. @lisp
  13888. (operating-system
  13889. ;; @dots{}
  13890. (services
  13891. (cons (udev-rules-service 'usb-thing %example-udev-rule)
  13892. %desktop-services)))
  13893. @end lisp
  13894. @end deffn
  13895. @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
  13896. Return a udev file named @var{file-name} containing the rules defined
  13897. within @var{file}, a file-like object.
  13898. The following example showcases how we can use an existing rule file.
  13899. @lisp
  13900. (use-modules (guix download) ;for url-fetch
  13901. (guix packages) ;for origin
  13902. @dots{})
  13903. (define %android-udev-rules
  13904. (file->udev-rule
  13905. "51-android-udev.rules"
  13906. (let ((version "20170910"))
  13907. (origin
  13908. (method url-fetch)
  13909. (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
  13910. "android-udev-rules/" version "/51-android.rules"))
  13911. (sha256
  13912. (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
  13913. @end lisp
  13914. @end deffn
  13915. Additionally, Guix package definitions can be included in @var{rules} in
  13916. order to extend the udev rules with the definitions found under their
  13917. @file{lib/udev/rules.d} sub-directory. In lieu of the previous
  13918. @var{file->udev-rule} example, we could have used the
  13919. @var{android-udev-rules} package which exists in Guix in the @code{(gnu
  13920. packages android)} module.
  13921. The following example shows how to use the @var{android-udev-rules}
  13922. package so that the Android tool @command{adb} can detect devices
  13923. without root privileges. It also details how to create the
  13924. @code{adbusers} group, which is required for the proper functioning of
  13925. the rules defined within the @code{android-udev-rules} package. To
  13926. create such a group, we must define it both as part of the
  13927. @code{supplementary-groups} of our @code{user-account} declaration, as
  13928. well as in the @var{groups} of the @code{udev-rules-service} procedure.
  13929. @lisp
  13930. (use-modules (gnu packages android) ;for android-udev-rules
  13931. (gnu system shadow) ;for user-group
  13932. @dots{})
  13933. (operating-system
  13934. ;; @dots{}
  13935. (users (cons (user-account
  13936. ;; @dots{}
  13937. (supplementary-groups
  13938. '("adbusers" ;for adb
  13939. "wheel" "netdev" "audio" "video")))))
  13940. ;; @dots{}
  13941. (services
  13942. (cons (udev-rules-service 'android android-udev-rules
  13943. #:groups '("adbusers"))
  13944. %desktop-services)))
  13945. @end lisp
  13946. @defvr {Scheme Variable} urandom-seed-service-type
  13947. Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
  13948. when rebooting. It also tries to seed @file{/dev/urandom} from
  13949. @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
  13950. readable.
  13951. @end defvr
  13952. @defvr {Scheme Variable} %random-seed-file
  13953. This is the name of the file where some random bytes are saved by
  13954. @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
  13955. It defaults to @file{/var/lib/random-seed}.
  13956. @end defvr
  13957. @cindex mouse
  13958. @cindex gpm
  13959. @defvr {Scheme Variable} gpm-service-type
  13960. This is the type of the service that runs GPM, the @dfn{general-purpose
  13961. mouse daemon}, which provides mouse support to the Linux console. GPM
  13962. allows users to use the mouse in the console, notably to select, copy,
  13963. and paste text.
  13964. The value for services of this type must be a @code{gpm-configuration}
  13965. (see below). This service is not part of @code{%base-services}.
  13966. @end defvr
  13967. @deftp {Data Type} gpm-configuration
  13968. Data type representing the configuration of GPM.
  13969. @table @asis
  13970. @item @code{options} (default: @code{%default-gpm-options})
  13971. Command-line options passed to @command{gpm}. The default set of
  13972. options instruct @command{gpm} to listen to mouse events on
  13973. @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
  13974. more information.
  13975. @item @code{gpm} (default: @code{gpm})
  13976. The GPM package to use.
  13977. @end table
  13978. @end deftp
  13979. @anchor{guix-publish-service-type}
  13980. @deffn {Scheme Variable} guix-publish-service-type
  13981. This is the service type for @command{guix publish} (@pxref{Invoking
  13982. guix publish}). Its value must be a @code{guix-publish-configuration}
  13983. object, as described below.
  13984. This assumes that @file{/etc/guix} already contains a signing key pair as
  13985. created by @command{guix archive --generate-key} (@pxref{Invoking guix
  13986. archive}). If that is not the case, the service will fail to start.
  13987. @end deffn
  13988. @deftp {Data Type} guix-publish-configuration
  13989. Data type representing the configuration of the @code{guix publish}
  13990. service.
  13991. @table @asis
  13992. @item @code{guix} (default: @code{guix})
  13993. The Guix package to use.
  13994. @item @code{port} (default: @code{80})
  13995. The TCP port to listen for connections.
  13996. @item @code{host} (default: @code{"localhost"})
  13997. The host (and thus, network interface) to listen to. Use
  13998. @code{"0.0.0.0"} to listen on all the network interfaces.
  13999. @item @code{advertise?} (default: @code{#f})
  14000. When true, advertise the service on the local network @i{via} the DNS-SD
  14001. protocol, using Avahi.
  14002. This allows neighboring Guix devices with discovery on (see
  14003. @code{guix-configuration} above) to discover this @command{guix publish}
  14004. instance and to automatically download substitutes from it.
  14005. @item @code{compression} (default: @code{'(("gzip" 3) ("zstd" 3))})
  14006. This is a list of compression method/level tuple used when compressing
  14007. substitutes. For example, to compress all substitutes with @emph{both} lzip
  14008. at level 7 and gzip at level 9, write:
  14009. @lisp
  14010. '(("lzip" 7) ("gzip" 9))
  14011. @end lisp
  14012. Level 9 achieves the best compression ratio at the expense of increased CPU
  14013. usage, whereas level 1 achieves fast compression. @xref{Invoking guix
  14014. publish}, for more information on the available compression methods and
  14015. the tradeoffs involved.
  14016. An empty list disables compression altogether.
  14017. @item @code{nar-path} (default: @code{"nar"})
  14018. The URL path at which ``nars'' can be fetched. @xref{Invoking guix
  14019. publish, @option{--nar-path}}, for details.
  14020. @item @code{cache} (default: @code{#f})
  14021. When it is @code{#f}, disable caching and instead generate archives on
  14022. demand. Otherwise, this should be the name of a directory---e.g.,
  14023. @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
  14024. archives and meta-data ready to be sent. @xref{Invoking guix publish,
  14025. @option{--cache}}, for more information on the tradeoffs involved.
  14026. @item @code{workers} (default: @code{#f})
  14027. When it is an integer, this is the number of worker threads used for
  14028. caching; when @code{#f}, the number of processors is used.
  14029. @xref{Invoking guix publish, @option{--workers}}, for more information.
  14030. @item @code{cache-bypass-threshold} (default: 10 MiB)
  14031. When @code{cache} is true, this is the maximum size in bytes of a store
  14032. item for which @command{guix publish} may bypass its cache in case of a
  14033. cache miss. @xref{Invoking guix publish,
  14034. @option{--cache-bypass-threshold}}, for more information.
  14035. @item @code{ttl} (default: @code{#f})
  14036. When it is an integer, this denotes the @dfn{time-to-live} in seconds
  14037. of the published archives. @xref{Invoking guix publish, @option{--ttl}},
  14038. for more information.
  14039. @item @code{negative-ttl} (default: @code{#f})
  14040. When it is an integer, this denotes the @dfn{time-to-live} in
  14041. seconds for the negative lookups. @xref{Invoking guix publish,
  14042. @option{--negative-ttl}}, for more information.
  14043. @end table
  14044. @end deftp
  14045. @anchor{rngd-service}
  14046. @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
  14047. [#:device "/dev/hwrng"]
  14048. Return a service that runs the @command{rngd} program from @var{rng-tools}
  14049. to add @var{device} to the kernel's entropy pool. The service will fail if
  14050. @var{device} does not exist.
  14051. @end deffn
  14052. @anchor{pam-limits-service}
  14053. @cindex session limits
  14054. @cindex ulimit
  14055. @cindex priority
  14056. @cindex realtime
  14057. @cindex jackd
  14058. @cindex nofile
  14059. @cindex open file descriptors
  14060. @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
  14061. Return a service that installs a configuration file for the
  14062. @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
  14063. @code{pam_limits} module}. The procedure optionally takes a list of
  14064. @code{pam-limits-entry} values, which can be used to specify
  14065. @code{ulimit} limits and @code{nice} priority limits to user sessions.
  14066. The following limits definition sets two hard and soft limits for all
  14067. login sessions of users in the @code{realtime} group:
  14068. @lisp
  14069. (pam-limits-service
  14070. (list
  14071. (pam-limits-entry "@@realtime" 'both 'rtprio 99)
  14072. (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
  14073. @end lisp
  14074. The first entry increases the maximum realtime priority for
  14075. non-privileged processes; the second entry lifts any restriction of the
  14076. maximum address space that can be locked in memory. These settings are
  14077. commonly used for real-time audio systems.
  14078. Another useful example is raising the maximum number of open file
  14079. descriptors that can be used:
  14080. @lisp
  14081. (pam-limits-service
  14082. (list
  14083. (pam-limits-entry "*" 'both 'nofile 100000)))
  14084. @end lisp
  14085. In the above example, the asterisk means the limit should apply to any
  14086. user. It is important to ensure the chosen value doesn't exceed the
  14087. maximum system value visible in the @file{/proc/sys/fs/file-max} file,
  14088. else the users would be prevented from login in. For more information
  14089. about the Pluggable Authentication Module (PAM) limits, refer to the
  14090. @samp{pam_limits} man page from the @code{linux-pam} package.
  14091. @end deffn
  14092. @node Scheduled Job Execution
  14093. @subsection Scheduled Job Execution
  14094. @cindex cron
  14095. @cindex mcron
  14096. @cindex scheduling jobs
  14097. The @code{(gnu services mcron)} module provides an interface to
  14098. GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
  14099. mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
  14100. Unix @command{cron} daemon; the main difference is that it is
  14101. implemented in Guile Scheme, which provides a lot of flexibility when
  14102. specifying the scheduling of jobs and their actions.
  14103. The example below defines an operating system that runs the
  14104. @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
  14105. and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
  14106. well as the @command{mkid} command on behalf of an unprivileged user
  14107. (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
  14108. gexps to introduce job definitions that are passed to mcron
  14109. (@pxref{G-Expressions}).
  14110. @lisp
  14111. (use-modules (guix) (gnu) (gnu services mcron))
  14112. (use-package-modules base idutils)
  14113. (define updatedb-job
  14114. ;; Run 'updatedb' at 3AM every day. Here we write the
  14115. ;; job's action as a Scheme procedure.
  14116. #~(job '(next-hour '(3))
  14117. (lambda ()
  14118. (execl (string-append #$findutils "/bin/updatedb")
  14119. "updatedb"
  14120. "--prunepaths=/tmp /var/tmp /gnu/store"))
  14121. "updatedb"))
  14122. (define garbage-collector-job
  14123. ;; Collect garbage 5 minutes after midnight every day.
  14124. ;; The job's action is a shell command.
  14125. #~(job "5 0 * * *" ;Vixie cron syntax
  14126. "guix gc -F 1G"))
  14127. (define idutils-job
  14128. ;; Update the index database as user "charlie" at 12:15PM
  14129. ;; and 19:15PM. This runs from the user's home directory.
  14130. #~(job '(next-minute-from (next-hour '(12 19)) '(15))
  14131. (string-append #$idutils "/bin/mkid src")
  14132. #:user "charlie"))
  14133. (operating-system
  14134. ;; @dots{}
  14135. ;; %BASE-SERVICES already includes an instance of
  14136. ;; 'mcron-service-type', which we extend with additional
  14137. ;; jobs using 'simple-service'.
  14138. (services (cons (simple-service 'my-cron-jobs
  14139. mcron-service-type
  14140. (list garbage-collector-job
  14141. updatedb-job
  14142. idutils-job))
  14143. %base-services)))
  14144. @end lisp
  14145. @quotation Tip
  14146. When providing the action of a job specification as a procedure, you
  14147. should provide an explicit name for the job via the optional 3rd
  14148. argument as done in the @code{updatedb-job} example above. Otherwise,
  14149. the job would appear as ``Lambda function'' in the output of
  14150. @command{herd schedule mcron}, which is not nearly descriptive enough!
  14151. @end quotation
  14152. For more complex jobs defined in Scheme where you need control over the top
  14153. level, for instance to introduce a @code{use-modules} form, you can move your
  14154. code to a separate program using the @code{program-file} procedure of the
  14155. @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
  14156. illustrates that.
  14157. @lisp
  14158. (define %battery-alert-job
  14159. ;; Beep when the battery percentage falls below %MIN-LEVEL.
  14160. #~(job
  14161. '(next-minute (range 0 60 1))
  14162. #$(program-file
  14163. "battery-alert.scm"
  14164. (with-imported-modules (source-module-closure
  14165. '((guix build utils)))
  14166. #~(begin
  14167. (use-modules (guix build utils)
  14168. (ice-9 popen)
  14169. (ice-9 regex)
  14170. (ice-9 textual-ports)
  14171. (srfi srfi-2))
  14172. (define %min-level 20)
  14173. (setenv "LC_ALL" "C") ;ensure English output
  14174. (and-let* ((input-pipe (open-pipe*
  14175. OPEN_READ
  14176. #$(file-append acpi "/bin/acpi")))
  14177. (output (get-string-all input-pipe))
  14178. (m (string-match "Discharging, ([0-9]+)%" output))
  14179. (level (string->number (match:substring m 1)))
  14180. ((< level %min-level)))
  14181. (format #t "warning: Battery level is low (~a%)~%" level)
  14182. (invoke #$(file-append beep "/bin/beep") "-r5")))))))
  14183. @end lisp
  14184. @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
  14185. for more information on mcron job specifications. Below is the
  14186. reference of the mcron service.
  14187. On a running system, you can use the @code{schedule} action of the service to
  14188. visualize the mcron jobs that will be executed next:
  14189. @example
  14190. # herd schedule mcron
  14191. @end example
  14192. @noindent
  14193. The example above lists the next five tasks that will be executed, but you can
  14194. also specify the number of tasks to display:
  14195. @example
  14196. # herd schedule mcron 10
  14197. @end example
  14198. @defvr {Scheme Variable} mcron-service-type
  14199. This is the type of the @code{mcron} service, whose value is an
  14200. @code{mcron-configuration} object.
  14201. This service type can be the target of a service extension that provides
  14202. additional job specifications (@pxref{Service Composition}). In other
  14203. words, it is possible to define services that provide additional mcron
  14204. jobs to run.
  14205. @end defvr
  14206. @deftp {Data Type} mcron-configuration
  14207. Data type representing the configuration of mcron.
  14208. @table @asis
  14209. @item @code{mcron} (default: @var{mcron})
  14210. The mcron package to use.
  14211. @item @code{jobs}
  14212. This is a list of gexps (@pxref{G-Expressions}), where each gexp
  14213. corresponds to an mcron job specification (@pxref{Syntax, mcron job
  14214. specifications,, mcron, GNU@tie{}mcron}).
  14215. @end table
  14216. @end deftp
  14217. @node Log Rotation
  14218. @subsection Log Rotation
  14219. @cindex rottlog
  14220. @cindex log rotation
  14221. @cindex logging
  14222. Log files such as those found in @file{/var/log} tend to grow endlessly,
  14223. so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
  14224. their contents in separate files, possibly compressed. The @code{(gnu
  14225. services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
  14226. log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
  14227. This service is part of @code{%base-services}, and thus enabled by
  14228. default, with the default settings, for commonly encountered log files.
  14229. The example below shows how to extend it with an additional
  14230. @dfn{rotation}, should you need to do that (usually, services that
  14231. produce log files already take care of that):
  14232. @lisp
  14233. (use-modules (guix) (gnu))
  14234. (use-service-modules admin)
  14235. (define my-log-files
  14236. ;; Log files that I want to rotate.
  14237. '("/var/log/something.log" "/var/log/another.log"))
  14238. (operating-system
  14239. ;; @dots{}
  14240. (services (cons (simple-service 'rotate-my-stuff
  14241. rottlog-service-type
  14242. (list (log-rotation
  14243. (frequency 'daily)
  14244. (files my-log-files))))
  14245. %base-services)))
  14246. @end lisp
  14247. @defvr {Scheme Variable} rottlog-service-type
  14248. This is the type of the Rottlog service, whose value is a
  14249. @code{rottlog-configuration} object.
  14250. Other services can extend this one with new @code{log-rotation} objects
  14251. (see below), thereby augmenting the set of files to be rotated.
  14252. This service type can define mcron jobs (@pxref{Scheduled Job
  14253. Execution}) to run the rottlog service.
  14254. @end defvr
  14255. @deftp {Data Type} rottlog-configuration
  14256. Data type representing the configuration of rottlog.
  14257. @table @asis
  14258. @item @code{rottlog} (default: @code{rottlog})
  14259. The Rottlog package to use.
  14260. @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
  14261. The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
  14262. rottlog, GNU Rot[t]log Manual}).
  14263. @item @code{rotations} (default: @code{%default-rotations})
  14264. A list of @code{log-rotation} objects as defined below.
  14265. @item @code{jobs}
  14266. This is a list of gexps where each gexp corresponds to an mcron job
  14267. specification (@pxref{Scheduled Job Execution}).
  14268. @end table
  14269. @end deftp
  14270. @deftp {Data Type} log-rotation
  14271. Data type representing the rotation of a group of log files.
  14272. Taking an example from the Rottlog manual (@pxref{Period Related File
  14273. Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
  14274. defined like this:
  14275. @lisp
  14276. (log-rotation
  14277. (frequency 'daily)
  14278. (files '("/var/log/apache/*"))
  14279. (options '("storedir apache-archives"
  14280. "rotate 6"
  14281. "notifempty"
  14282. "nocompress")))
  14283. @end lisp
  14284. The list of fields is as follows:
  14285. @table @asis
  14286. @item @code{frequency} (default: @code{'weekly})
  14287. The log rotation frequency, a symbol.
  14288. @item @code{files}
  14289. The list of files or file glob patterns to rotate.
  14290. @item @code{options} (default: @code{'()})
  14291. The list of rottlog options for this rotation (@pxref{Configuration
  14292. parameters,,, rottlog, GNU Rot[t]lg Manual}).
  14293. @item @code{post-rotate} (default: @code{#f})
  14294. Either @code{#f} or a gexp to execute once the rotation has completed.
  14295. @end table
  14296. @end deftp
  14297. @defvr {Scheme Variable} %default-rotations
  14298. Specifies weekly rotation of @code{%rotated-files} and of
  14299. @file{/var/log/guix-daemon.log}.
  14300. @end defvr
  14301. @defvr {Scheme Variable} %rotated-files
  14302. The list of syslog-controlled files to be rotated. By default it is:
  14303. @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
  14304. "/var/log/maillog")}.
  14305. @end defvr
  14306. Some log files just need to be deleted periodically once they are old,
  14307. without any other criterion and without any archival step. This is the
  14308. case of build logs stored by @command{guix-daemon} under
  14309. @file{/var/log/guix/drvs} (@pxref{Invoking guix-daemon}). The
  14310. @code{log-cleanup} service addresses this use case. For example,
  14311. @code{%base-services} (@pxref{Base Services}) includes the following:
  14312. @lisp
  14313. ;; Periodically delete old build logs.
  14314. (service log-cleanup-service-type
  14315. (log-cleanup-configuration
  14316. (directory "/var/log/guix/drvs")))
  14317. @end lisp
  14318. That ensures build logs do not accumulate endlessly.
  14319. @defvr {Scheme Variable} log-cleanup-service-type
  14320. This is the type of the service to delete old logs. Its value must be a
  14321. @code{log-cleanup-configuration} record as described below.
  14322. @end defvr
  14323. @deftp {Data Type} log-cleanup-configuration
  14324. Data type representing the log cleanup configuration
  14325. @table @asis
  14326. @item @code{directory}
  14327. Name of the directory containing log files.
  14328. @item @code{expiry} (default: @code{(* 6 30 24 3600)})
  14329. Age in seconds after which a file is subject to deletion (six months by
  14330. default).
  14331. @item @code{schedule} (default: @code{"30 12 01,08,15,22 * *"})
  14332. String or gexp denoting the corresponding mcron job schedule
  14333. (@pxref{Scheduled Job Execution}).
  14334. @end table
  14335. @end deftp
  14336. @node Networking Setup
  14337. @subsection Networking Setup
  14338. The @code{(gnu services networking)} module provides services to
  14339. configure network interfaces and set up networking on your machine.
  14340. Those services provide different ways for you to set up your machine: by
  14341. declaring a static network configuration, by running a Dynamic Host
  14342. Configuration Protocol (DHCP) client, or by running daemons such as
  14343. NetworkManager and Connman that automate the whole process,
  14344. automatically adapt to connectivity changes, and provide a high-level
  14345. user interface.
  14346. On a laptop, NetworkManager and Connman are by far the most convenient
  14347. options, which is why the default desktop services include
  14348. NetworkManager (@pxref{Desktop Services, @code{%desktop-services}}).
  14349. For a server, or for a virtual machine or a container, static network
  14350. configuration or a simple DHCP client are often more appropriate.
  14351. This section describes the various network setup services available,
  14352. starting with static network configuration.
  14353. @defvr {Scheme Variable} static-networking-service-type
  14354. This is the type for statically-configured network interfaces. Its
  14355. value must be a list of @code{static-networking} records. Each of them
  14356. declares a set of @dfn{addresses}, @dfn{routes}, and @dfn{links}, as
  14357. show below.
  14358. @cindex network interface controller (NIC)
  14359. @cindex NIC, networking interface controller
  14360. Here is the simplest configuration, with only one network interface
  14361. controller (NIC) and only IPv4 connectivity:
  14362. @lisp
  14363. ;; Static networking for one NIC, IPv4-only.
  14364. (service static-networking-service-type
  14365. (list (static-networking
  14366. (addresses
  14367. (list (network-address
  14368. (device "eno1")
  14369. (value "10.0.2.15/24"))))
  14370. (routes
  14371. (list (network-route
  14372. (destination "default")
  14373. (gateway "10.0.2.2"))))
  14374. (name-servers '("10.0.2.3")))))
  14375. @end lisp
  14376. The snippet above can be added to the @code{services} field of your
  14377. operating system configuration (@pxref{Using the Configuration System}).
  14378. It will configure your machine to have 10.0.2.15 as its IP address, with
  14379. a 24-bit netmask for the local network---meaning that any 10.0.2.@var{x}
  14380. address is on the local area network (LAN). Traffic to addresses
  14381. outside the local network is routed @i{via} 10.0.2.2. Host names are
  14382. resolved by sending domain name system (DNS) queries to 10.0.2.3.
  14383. @end defvr
  14384. @deftp {Data Type} static-networking
  14385. This is the data type representing a static network configuration.
  14386. As an example, here is how you would declare the configuration of a
  14387. machine with a single network interface controller (NIC) available as
  14388. @code{eno1}, and with one IPv4 and one IPv6 address:
  14389. @lisp
  14390. ;; Network configuration for one NIC, IPv4 + IPv6.
  14391. (static-networking
  14392. (addresses (list (network-address
  14393. (device "eno1")
  14394. (value "10.0.2.15/24"))
  14395. (network-address
  14396. (device "eno1")
  14397. (value "2001:123:4567:101::1/64"))))
  14398. (routes (list (network-route
  14399. (destination "default")
  14400. (gateway "10.0.2.2"))
  14401. (network-route
  14402. (destination "default")
  14403. (gateway "2020:321:4567:42::1"))))
  14404. (name-servers '("10.0.2.3")))
  14405. @end lisp
  14406. If you are familiar with the @command{ip} command of the
  14407. @uref{https://wiki.linuxfoundation.org/networking/iproute2,
  14408. @code{iproute2} package} found on Linux-based systems, the declaration
  14409. above is equivalent to typing:
  14410. @example
  14411. ip address add 10.0.2.15/24 dev eno1
  14412. ip address add 2001:123:4567:101::1/64 dev eno1
  14413. ip route add default via inet 10.0.2.2
  14414. ip route add default via inet6 2020:321:4567:42::1
  14415. @end example
  14416. Run @command{man 8 ip} for more info. Venerable GNU/Linux users will
  14417. certainly know how to do it with @command{ifconfig} and @command{route},
  14418. but we'll spare you that.
  14419. The available fields of this data type are as follows:
  14420. @table @asis
  14421. @item @code{addresses}
  14422. @itemx @code{links} (default: @code{'()})
  14423. @itemx @code{routes} (default: @code{'()})
  14424. The list of @code{network-address}, @code{network-link}, and
  14425. @code{network-route} records for this network (see below).
  14426. @item @code{name-servers} (default: @code{'()})
  14427. The list of IP addresses (strings) of domain name servers. These IP
  14428. addresses go to @file{/etc/resolv.conf}.
  14429. @item @code{provision} (default: @code{'(networking)})
  14430. If true, this should be a list of symbols for the Shepherd service
  14431. corresponding to this network configuration.
  14432. @item @code{requirement} (default @code{'()})
  14433. The list of Shepherd services depended on.
  14434. @end table
  14435. @end deftp
  14436. @deftp {Data Type} network-address
  14437. This is the data type representing the IP address of a network
  14438. interface.
  14439. @table @code
  14440. @item device
  14441. The name of the network interface for this address---e.g.,
  14442. @code{"eno1"}.
  14443. @item value
  14444. The actual IP address and network mask, in
  14445. @uref{https://en.wikipedia.org/wiki/CIDR#CIDR_notation, @acronym{CIDR,
  14446. Classless Inter-Domain Routing} notation}, as a string.
  14447. For example, @code{"10.0.2.15/24"} denotes IPv4 address 10.0.2.15 on a
  14448. 24-bit sub-network---all 10.0.2.@var{x} addresses are on the same local
  14449. network.
  14450. @item ipv6?
  14451. Whether @code{value} denotes an IPv6 address. By default this is
  14452. automatically determined.
  14453. @end table
  14454. @end deftp
  14455. @deftp {Data Type} network-route
  14456. This is the data type representing a network route.
  14457. @table @asis
  14458. @item @code{destination}
  14459. The route destination (a string), either an IP address or
  14460. @code{"default"} to denote the default route.
  14461. @item @code{source} (default: @code{#f})
  14462. The route source.
  14463. @item @code{device} (default: @code{#f})
  14464. The device used for this route---e.g., @code{"eno2"}.
  14465. @item @code{ipv6?} (default: auto)
  14466. Whether this is an IPv6 route. By default this is automatically
  14467. determined based on @code{destination} or @code{gateway}.
  14468. @item @code{gateway} (default: @code{#f})
  14469. IP address (a string) through which traffic is routed.
  14470. @end table
  14471. @end deftp
  14472. @deftp {Data Type} network-link
  14473. Data type for a network link (@pxref{Link,,, guile-netlink,
  14474. Guile-Netlink Manual}).
  14475. @table @code
  14476. @item name
  14477. The name of the link---e.g., @code{"v0p0"}.
  14478. @item type
  14479. A symbol denoting the type of the link---e.g., @code{'veth}.
  14480. @item arguments
  14481. List of arguments for this type of link.
  14482. @end table
  14483. @end deftp
  14484. @cindex loopback device
  14485. @defvr {Scheme Variable} %loopback-static-networking
  14486. This is the @code{static-networking} record representing the ``loopback
  14487. device'', @code{lo}, for IP addresses 127.0.0.1 and ::1, and providing
  14488. the @code{loopback} Shepherd service.
  14489. @end defvr
  14490. @cindex networking, with QEMU
  14491. @cindex QEMU, networking
  14492. @defvr {Scheme Variable} %qemu-static-networking
  14493. This is the @code{static-networking} record representing network setup
  14494. when using QEMU's user-mode network stack on @code{eth0} (@pxref{Using
  14495. the user mode network stack,,, QEMU, QEMU Documentation}).
  14496. @end defvr
  14497. @cindex DHCP, networking service
  14498. @defvr {Scheme Variable} dhcp-client-service-type
  14499. This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
  14500. Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
  14501. is the DHCP client package to use, @code{isc-dhcp} by default.
  14502. @end defvr
  14503. @cindex NetworkManager
  14504. @defvr {Scheme Variable} network-manager-service-type
  14505. This is the service type for the
  14506. @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
  14507. service. The value for this service type is a
  14508. @code{network-manager-configuration} record.
  14509. This service is part of @code{%desktop-services} (@pxref{Desktop
  14510. Services}).
  14511. @end defvr
  14512. @deftp {Data Type} network-manager-configuration
  14513. Data type representing the configuration of NetworkManager.
  14514. @table @asis
  14515. @item @code{network-manager} (default: @code{network-manager})
  14516. The NetworkManager package to use.
  14517. @item @code{dns} (default: @code{"default"})
  14518. Processing mode for DNS, which affects how NetworkManager uses the
  14519. @code{resolv.conf} configuration file.
  14520. @table @samp
  14521. @item default
  14522. NetworkManager will update @code{resolv.conf} to reflect the nameservers
  14523. provided by currently active connections.
  14524. @item dnsmasq
  14525. NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
  14526. @dfn{conditional forwarding} configuration if you are connected to a VPN, and
  14527. then update @code{resolv.conf} to point to the local nameserver.
  14528. With this setting, you can share your network connection. For example when
  14529. you want to share your network connection to another laptop @i{via} an
  14530. Ethernet cable, you can open @command{nm-connection-editor} and configure the
  14531. Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
  14532. and reestablish the connection (or reboot).
  14533. You can also set up a @dfn{host-to-guest connection} to QEMU VMs
  14534. (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
  14535. e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
  14536. browser on your host system, or connect to the VM @i{via} SSH
  14537. (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
  14538. host-to-guest connection, run this command once:
  14539. @example
  14540. nmcli connection add type tun \
  14541. connection.interface-name tap0 \
  14542. tun.mode tap tun.owner $(id -u) \
  14543. ipv4.method shared \
  14544. ipv4.addresses 172.28.112.1/24
  14545. @end example
  14546. Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
  14547. @option{-nic tap,ifname=tap0,script=no,downscript=no} to
  14548. @command{qemu-system-...}.
  14549. @item none
  14550. NetworkManager will not modify @code{resolv.conf}.
  14551. @end table
  14552. @item @code{vpn-plugins} (default: @code{'()})
  14553. This is the list of available plugins for virtual private networks
  14554. (VPNs). An example of this is the @code{network-manager-openvpn}
  14555. package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
  14556. @end table
  14557. @end deftp
  14558. @cindex Connman
  14559. @deffn {Scheme Variable} connman-service-type
  14560. This is the service type to run @url{https://01.org/connman,Connman},
  14561. a network connection manager.
  14562. Its value must be an
  14563. @code{connman-configuration} record as in this example:
  14564. @lisp
  14565. (service connman-service-type
  14566. (connman-configuration
  14567. (disable-vpn? #t)))
  14568. @end lisp
  14569. See below for details about @code{connman-configuration}.
  14570. @end deffn
  14571. @deftp {Data Type} connman-configuration
  14572. Data Type representing the configuration of connman.
  14573. @table @asis
  14574. @item @code{connman} (default: @var{connman})
  14575. The connman package to use.
  14576. @item @code{disable-vpn?} (default: @code{#f})
  14577. When true, disable connman's vpn plugin.
  14578. @end table
  14579. @end deftp
  14580. @cindex WPA Supplicant
  14581. @defvr {Scheme Variable} wpa-supplicant-service-type
  14582. This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
  14583. supplicant}, an authentication daemon required to authenticate against
  14584. encrypted WiFi or ethernet networks.
  14585. @end defvr
  14586. @deftp {Data Type} wpa-supplicant-configuration
  14587. Data type representing the configuration of WPA Supplicant.
  14588. It takes the following parameters:
  14589. @table @asis
  14590. @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
  14591. The WPA Supplicant package to use.
  14592. @item @code{requirement} (default: @code{'(user-processes loopback syslogd)}
  14593. List of services that should be started before WPA Supplicant starts.
  14594. @item @code{dbus?} (default: @code{#t})
  14595. Whether to listen for requests on D-Bus.
  14596. @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
  14597. Where to store the PID file.
  14598. @item @code{interface} (default: @code{#f})
  14599. If this is set, it must specify the name of a network interface that
  14600. WPA supplicant will control.
  14601. @item @code{config-file} (default: @code{#f})
  14602. Optional configuration file to use.
  14603. @item @code{extra-options} (default: @code{'()})
  14604. List of additional command-line arguments to pass to the daemon.
  14605. @end table
  14606. @end deftp
  14607. @cindex wicd
  14608. @cindex wireless
  14609. @cindex WiFi
  14610. @cindex network management
  14611. @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
  14612. Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
  14613. management daemon that aims to simplify wired and wireless networking.
  14614. This service adds the @var{wicd} package to the global profile, providing
  14615. several commands to interact with the daemon and configure networking:
  14616. @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
  14617. and @command{wicd-curses} user interfaces.
  14618. @end deffn
  14619. @cindex ModemManager
  14620. Some networking devices such as modems require special care, and this is
  14621. what the services below focus on.
  14622. @defvr {Scheme Variable} modem-manager-service-type
  14623. This is the service type for the
  14624. @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
  14625. service. The value for this service type is a
  14626. @code{modem-manager-configuration} record.
  14627. This service is part of @code{%desktop-services} (@pxref{Desktop
  14628. Services}).
  14629. @end defvr
  14630. @deftp {Data Type} modem-manager-configuration
  14631. Data type representing the configuration of ModemManager.
  14632. @table @asis
  14633. @item @code{modem-manager} (default: @code{modem-manager})
  14634. The ModemManager package to use.
  14635. @end table
  14636. @end deftp
  14637. @cindex USB_ModeSwitch
  14638. @cindex Modeswitching
  14639. @defvr {Scheme Variable} usb-modeswitch-service-type
  14640. This is the service type for the
  14641. @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch}
  14642. service. The value for this service type is
  14643. a @code{usb-modeswitch-configuration} record.
  14644. When plugged in, some USB modems (and other USB devices) initially present
  14645. themselves as a read-only storage medium and not as a modem. They need to be
  14646. @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
  14647. installs udev rules to automatically modeswitch these devices when they are
  14648. plugged in.
  14649. This service is part of @code{%desktop-services} (@pxref{Desktop
  14650. Services}).
  14651. @end defvr
  14652. @deftp {Data Type} usb-modeswitch-configuration
  14653. Data type representing the configuration of USB_ModeSwitch.
  14654. @table @asis
  14655. @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
  14656. The USB_ModeSwitch package providing the binaries for modeswitching.
  14657. @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
  14658. The package providing the device data and udev rules file used by
  14659. USB_ModeSwitch.
  14660. @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
  14661. Which config file to use for the USB_ModeSwitch dispatcher. By default the
  14662. config file shipped with USB_ModeSwitch is used which disables logging to
  14663. @file{/var/log} among other default settings. If set to @code{#f}, no config
  14664. file is used.
  14665. @end table
  14666. @end deftp
  14667. @node Networking Services
  14668. @subsection Networking Services
  14669. The @code{(gnu services networking)} module discussed in the previous
  14670. section provides services for more advanced setups: providing a DHCP
  14671. service for others to use, filtering packets with iptables or nftables,
  14672. running a WiFi access point with @command{hostapd}, running the
  14673. @command{inetd} ``superdaemon'', and more. This section describes
  14674. those.
  14675. @deffn {Scheme Procedure} dhcpd-service-type
  14676. This type defines a service that runs a DHCP daemon. To create a
  14677. service of this type, you must supply a @code{<dhcpd-configuration>}.
  14678. For example:
  14679. @lisp
  14680. (service dhcpd-service-type
  14681. (dhcpd-configuration
  14682. (config-file (local-file "my-dhcpd.conf"))
  14683. (interfaces '("enp0s25"))))
  14684. @end lisp
  14685. @end deffn
  14686. @deftp {Data Type} dhcpd-configuration
  14687. @table @asis
  14688. @item @code{package} (default: @code{isc-dhcp})
  14689. The package that provides the DHCP daemon. This package is expected to
  14690. provide the daemon at @file{sbin/dhcpd} relative to its output
  14691. directory. The default package is the
  14692. @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
  14693. @item @code{config-file} (default: @code{#f})
  14694. The configuration file to use. This is required. It will be passed to
  14695. @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
  14696. object (@pxref{G-Expressions, file-like objects}). See @code{man
  14697. dhcpd.conf} for details on the configuration file syntax.
  14698. @item @code{version} (default: @code{"4"})
  14699. The DHCP version to use. The ISC DHCP server supports the values ``4'',
  14700. ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
  14701. options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
  14702. details.
  14703. @item @code{run-directory} (default: @code{"/run/dhcpd"})
  14704. The run directory to use. At service activation time, this directory
  14705. will be created if it does not exist.
  14706. @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
  14707. The PID file to use. This corresponds to the @code{-pf} option of
  14708. @code{dhcpd}. See @code{man dhcpd} for details.
  14709. @item @code{interfaces} (default: @code{'()})
  14710. The names of the network interfaces on which dhcpd should listen for
  14711. broadcasts. If this list is not empty, then its elements (which must be
  14712. strings) will be appended to the @code{dhcpd} invocation when starting
  14713. the daemon. It may not be necessary to explicitly specify any
  14714. interfaces here; see @code{man dhcpd} for details.
  14715. @end table
  14716. @end deftp
  14717. @cindex hostapd service, for Wi-Fi access points
  14718. @cindex Wi-Fi access points, hostapd service
  14719. @defvr {Scheme Variable} hostapd-service-type
  14720. This is the service type to run the @uref{https://w1.fi/hostapd/,
  14721. hostapd} daemon to set up WiFi (IEEE 802.11) access points and
  14722. authentication servers. Its associated value must be a
  14723. @code{hostapd-configuration} as shown below:
  14724. @lisp
  14725. ;; Use wlan1 to run the access point for "My Network".
  14726. (service hostapd-service-type
  14727. (hostapd-configuration
  14728. (interface "wlan1")
  14729. (ssid "My Network")
  14730. (channel 12)))
  14731. @end lisp
  14732. @end defvr
  14733. @deftp {Data Type} hostapd-configuration
  14734. This data type represents the configuration of the hostapd service, with
  14735. the following fields:
  14736. @table @asis
  14737. @item @code{package} (default: @code{hostapd})
  14738. The hostapd package to use.
  14739. @item @code{interface} (default: @code{"wlan0"})
  14740. The network interface to run the WiFi access point.
  14741. @item @code{ssid}
  14742. The SSID (@dfn{service set identifier}), a string that identifies this
  14743. network.
  14744. @item @code{broadcast-ssid?} (default: @code{#t})
  14745. Whether to broadcast this SSID.
  14746. @item @code{channel} (default: @code{1})
  14747. The WiFi channel to use.
  14748. @item @code{driver} (default: @code{"nl80211"})
  14749. The driver interface type. @code{"nl80211"} is used with all Linux
  14750. mac80211 drivers. Use @code{"none"} if building hostapd as a standalone
  14751. RADIUS server that does # not control any wireless/wired driver.
  14752. @item @code{extra-settings} (default: @code{""})
  14753. Extra settings to append as-is to the hostapd configuration file. See
  14754. @uref{https://w1.fi/cgit/hostap/plain/hostapd/hostapd.conf} for the
  14755. configuration file reference.
  14756. @end table
  14757. @end deftp
  14758. @defvr {Scheme Variable} simulated-wifi-service-type
  14759. This is the type of a service to simulate WiFi networking, which can be
  14760. useful in virtual machines for testing purposes. The service loads the
  14761. Linux kernel
  14762. @uref{https://www.kernel.org/doc/html/latest/networking/mac80211_hwsim/mac80211_hwsim.html,
  14763. @code{mac80211_hwsim} module} and starts hostapd to create a pseudo WiFi
  14764. network that can be seen on @code{wlan0}, by default.
  14765. The service's value is a @code{hostapd-configuration} record.
  14766. @end defvr
  14767. @cindex iptables
  14768. @defvr {Scheme Variable} iptables-service-type
  14769. This is the service type to set up an iptables configuration. iptables is a
  14770. packet filtering framework supported by the Linux kernel. This service
  14771. supports configuring iptables for both IPv4 and IPv6. A simple example
  14772. configuration rejecting all incoming connections except those to the ssh port
  14773. 22 is shown below.
  14774. @lisp
  14775. (service iptables-service-type
  14776. (iptables-configuration
  14777. (ipv4-rules (plain-file "iptables.rules" "*filter
  14778. :INPUT ACCEPT
  14779. :FORWARD ACCEPT
  14780. :OUTPUT ACCEPT
  14781. -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
  14782. -A INPUT -p tcp --dport 22 -j ACCEPT
  14783. -A INPUT -j REJECT --reject-with icmp-port-unreachable
  14784. COMMIT
  14785. "))
  14786. (ipv6-rules (plain-file "ip6tables.rules" "*filter
  14787. :INPUT ACCEPT
  14788. :FORWARD ACCEPT
  14789. :OUTPUT ACCEPT
  14790. -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
  14791. -A INPUT -p tcp --dport 22 -j ACCEPT
  14792. -A INPUT -j REJECT --reject-with icmp6-port-unreachable
  14793. COMMIT
  14794. "))))
  14795. @end lisp
  14796. @end defvr
  14797. @deftp {Data Type} iptables-configuration
  14798. The data type representing the configuration of iptables.
  14799. @table @asis
  14800. @item @code{iptables} (default: @code{iptables})
  14801. The iptables package that provides @code{iptables-restore} and
  14802. @code{ip6tables-restore}.
  14803. @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
  14804. The iptables rules to use. It will be passed to @code{iptables-restore}.
  14805. This may be any ``file-like'' object (@pxref{G-Expressions, file-like
  14806. objects}).
  14807. @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
  14808. The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
  14809. This may be any ``file-like'' object (@pxref{G-Expressions, file-like
  14810. objects}).
  14811. @end table
  14812. @end deftp
  14813. @cindex nftables
  14814. @defvr {Scheme Variable} nftables-service-type
  14815. This is the service type to set up a nftables configuration. nftables is a
  14816. netfilter project that aims to replace the existing iptables, ip6tables,
  14817. arptables and ebtables framework. It provides a new packet filtering
  14818. framework, a new user-space utility @command{nft}, and a compatibility layer
  14819. for iptables. This service comes with a default ruleset
  14820. @code{%default-nftables-ruleset} that rejecting all incoming connections
  14821. except those to the ssh port 22. To use it, simply write:
  14822. @lisp
  14823. (service nftables-service-type)
  14824. @end lisp
  14825. @end defvr
  14826. @deftp {Data Type} nftables-configuration
  14827. The data type representing the configuration of nftables.
  14828. @table @asis
  14829. @item @code{package} (default: @code{nftables})
  14830. The nftables package that provides @command{nft}.
  14831. @item @code{ruleset} (default: @code{%default-nftables-ruleset})
  14832. The nftables ruleset to use. This may be any ``file-like'' object
  14833. (@pxref{G-Expressions, file-like objects}).
  14834. @end table
  14835. @end deftp
  14836. @cindex NTP (Network Time Protocol), service
  14837. @cindex ntpd, service for the Network Time Protocol daemon
  14838. @cindex real time clock
  14839. @defvr {Scheme Variable} ntp-service-type
  14840. This is the type of the service running the @uref{https://www.ntp.org,
  14841. Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
  14842. system clock synchronized with that of the specified NTP servers.
  14843. The value of this service is an @code{ntpd-configuration} object, as described
  14844. below.
  14845. @end defvr
  14846. @deftp {Data Type} ntp-configuration
  14847. This is the data type for the NTP service configuration.
  14848. @table @asis
  14849. @item @code{servers} (default: @code{%ntp-servers})
  14850. This is the list of servers (@code{<ntp-server>} records) with which
  14851. @command{ntpd} will be synchronized. See the @code{ntp-server} data type
  14852. definition below.
  14853. @item @code{allow-large-adjustment?} (default: @code{#t})
  14854. This determines whether @command{ntpd} is allowed to make an initial
  14855. adjustment of more than 1,000 seconds.
  14856. @item @code{ntp} (default: @code{ntp})
  14857. The NTP package to use.
  14858. @end table
  14859. @end deftp
  14860. @defvr {Scheme Variable} %ntp-servers
  14861. List of host names used as the default NTP servers. These are servers of the
  14862. @uref{https://www.ntppool.org/en/, NTP Pool Project}.
  14863. @end defvr
  14864. @deftp {Data Type} ntp-server
  14865. The data type representing the configuration of a NTP server.
  14866. @table @asis
  14867. @item @code{type} (default: @code{'server})
  14868. The type of the NTP server, given as a symbol. One of @code{'pool},
  14869. @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
  14870. @item @code{address}
  14871. The address of the server, as a string.
  14872. @item @code{options}
  14873. NTPD options to use with that specific server, given as a list of option names
  14874. and/or of option names and values tuples. The following example define a server
  14875. to use with the options @option{iburst} and @option{prefer}, as well as
  14876. @option{version} 3 and a @option{maxpoll} time of 16 seconds.
  14877. @example
  14878. (ntp-server
  14879. (type 'server)
  14880. (address "some.ntp.server.org")
  14881. (options `(iburst (version 3) (maxpoll 16) prefer))))
  14882. @end example
  14883. @end table
  14884. @end deftp
  14885. @cindex OpenNTPD
  14886. @deffn {Scheme Procedure} openntpd-service-type
  14887. Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
  14888. by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
  14889. clock synchronized with that of the given servers.
  14890. @lisp
  14891. (service
  14892. openntpd-service-type
  14893. (openntpd-configuration
  14894. (listen-on '("127.0.0.1" "::1"))
  14895. (sensor '("udcf0 correction 70000"))
  14896. (constraint-from '("www.gnu.org"))
  14897. (constraints-from '("https://www.google.com/"))))
  14898. @end lisp
  14899. @end deffn
  14900. @defvr {Scheme Variable} %openntpd-servers
  14901. This variable is a list of the server addresses defined in
  14902. @code{%ntp-servers}.
  14903. @end defvr
  14904. @deftp {Data Type} openntpd-configuration
  14905. @table @asis
  14906. @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
  14907. The openntpd executable to use.
  14908. @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
  14909. A list of local IP addresses or hostnames the ntpd daemon should listen on.
  14910. @item @code{query-from} (default: @code{'()})
  14911. A list of local IP address the ntpd daemon should use for outgoing queries.
  14912. @item @code{sensor} (default: @code{'()})
  14913. Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
  14914. will listen to each sensor that actually exists and ignore non-existent ones.
  14915. See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
  14916. information.
  14917. @item @code{server} (default: @code{'()})
  14918. Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
  14919. @item @code{servers} (default: @code{%openntp-servers})
  14920. Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
  14921. @item @code{constraint-from} (default: @code{'()})
  14922. @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
  14923. This time information is not used for precision but acts as an authenticated
  14924. constraint, thereby reducing the impact of unauthenticated NTP
  14925. man-in-the-middle attacks.
  14926. Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
  14927. a constraint.
  14928. @item @code{constraints-from} (default: @code{'()})
  14929. As with constraint from, specify a list of URLs, IP addresses or hostnames of
  14930. HTTPS servers to provide a constraint. Should the hostname resolve to multiple
  14931. IP addresses, @code{ntpd} will calculate a median constraint from all of them.
  14932. @end table
  14933. @end deftp
  14934. @cindex inetd
  14935. @deffn {Scheme variable} inetd-service-type
  14936. This service runs the @command{inetd} (@pxref{inetd invocation,,,
  14937. inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
  14938. connections on internet sockets, and lazily starts the specified server
  14939. program when a connection is made on one of these sockets.
  14940. The value of this service is an @code{inetd-configuration} object. The
  14941. following example configures the @command{inetd} daemon to provide the
  14942. built-in @command{echo} service, as well as an smtp service which
  14943. forwards smtp traffic over ssh to a server @code{smtp-server} behind a
  14944. gateway @code{hostname}:
  14945. @lisp
  14946. (service
  14947. inetd-service-type
  14948. (inetd-configuration
  14949. (entries (list
  14950. (inetd-entry
  14951. (name "echo")
  14952. (socket-type 'stream)
  14953. (protocol "tcp")
  14954. (wait? #f)
  14955. (user "root"))
  14956. (inetd-entry
  14957. (node "127.0.0.1")
  14958. (name "smtp")
  14959. (socket-type 'stream)
  14960. (protocol "tcp")
  14961. (wait? #f)
  14962. (user "root")
  14963. (program (file-append openssh "/bin/ssh"))
  14964. (arguments
  14965. '("ssh" "-qT" "-i" "/path/to/ssh_key"
  14966. "-W" "smtp-server:25" "user@@hostname")))))))
  14967. @end lisp
  14968. See below for more details about @code{inetd-configuration}.
  14969. @end deffn
  14970. @deftp {Data Type} inetd-configuration
  14971. Data type representing the configuration of @command{inetd}.
  14972. @table @asis
  14973. @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
  14974. The @command{inetd} executable to use.
  14975. @item @code{entries} (default: @code{'()})
  14976. A list of @command{inetd} service entries. Each entry should be created
  14977. by the @code{inetd-entry} constructor.
  14978. @end table
  14979. @end deftp
  14980. @deftp {Data Type} inetd-entry
  14981. Data type representing an entry in the @command{inetd} configuration.
  14982. Each entry corresponds to a socket where @command{inetd} will listen for
  14983. requests.
  14984. @table @asis
  14985. @item @code{node} (default: @code{#f})
  14986. Optional string, a comma-separated list of local addresses
  14987. @command{inetd} should use when listening for this service.
  14988. @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
  14989. description of all options.
  14990. @item @code{name}
  14991. A string, the name must correspond to an entry in @code{/etc/services}.
  14992. @item @code{socket-type}
  14993. One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
  14994. @code{'seqpacket}.
  14995. @item @code{protocol}
  14996. A string, must correspond to an entry in @code{/etc/protocols}.
  14997. @item @code{wait?} (default: @code{#t})
  14998. Whether @command{inetd} should wait for the server to exit before
  14999. listening to new service requests.
  15000. @item @code{user}
  15001. A string containing the user (and, optionally, group) name of the user
  15002. as whom the server should run. The group name can be specified in a
  15003. suffix, separated by a colon or period, i.e.@: @code{"user"},
  15004. @code{"user:group"} or @code{"user.group"}.
  15005. @item @code{program} (default: @code{"internal"})
  15006. The server program which will serve the requests, or @code{"internal"}
  15007. if @command{inetd} should use a built-in service.
  15008. @item @code{arguments} (default: @code{'()})
  15009. A list strings or file-like objects, which are the server program's
  15010. arguments, starting with the zeroth argument, i.e.@: the name of the
  15011. program itself. For @command{inetd}'s internal services, this entry
  15012. must be @code{'()} or @code{'("internal")}.
  15013. @end table
  15014. @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
  15015. detailed discussion of each configuration field.
  15016. @end deftp
  15017. @cindex opendht, distributed hash table network service
  15018. @cindex dhtproxy, for use with jami
  15019. @defvr {Scheme Variable} opendht-service-type
  15020. This is the type of the service running a @uref{https://opendht.net,
  15021. OpenDHT} node, @command{dhtnode}. The daemon can be used to host your
  15022. own proxy service to the distributed hash table (DHT), for example to
  15023. connect to with Jami, among other applications.
  15024. @quotation Important
  15025. When using the OpenDHT proxy server, the IP addresses it ``sees'' from
  15026. the clients should be addresses reachable from other peers. In practice
  15027. this means that a publicly reachable address is best suited for a proxy
  15028. server, outside of your private network. For example, hosting the proxy
  15029. server on a IPv4 private local network and exposing it via port
  15030. forwarding could work for external peers, but peers local to the proxy
  15031. would have their private addresses shared with the external peers,
  15032. leading to connectivity problems.
  15033. @end quotation
  15034. The value of this service is a @code{opendht-configuration} object, as
  15035. described below.
  15036. @end defvr
  15037. @deftp {Data Type} opendht-configuration
  15038. This is the data type for the OpenDHT service configuration.
  15039. @c The fields documentation has been auto-generated using the
  15040. @c configuration->documentation procedure from
  15041. @c (gnu services configuration).
  15042. Available @code{opendht-configuration} fields are:
  15043. @deftypevr {@code{opendht-configuration} parameter} package opendht
  15044. The @code{opendht} package to use.
  15045. @end deftypevr
  15046. @deftypevr {@code{opendht-configuration} parameter} boolean peer-discovery?
  15047. Whether to enable the multicast local peer discovery mechanism.
  15048. Defaults to @samp{#f}.
  15049. @end deftypevr
  15050. @deftypevr {@code{opendht-configuration} parameter} boolean enable-logging?
  15051. Whether to enable logging messages to syslog. It is disabled by default
  15052. as it is rather verbose.
  15053. Defaults to @samp{#f}.
  15054. @end deftypevr
  15055. @deftypevr {@code{opendht-configuration} parameter} boolean debug?
  15056. Whether to enable debug-level logging messages. This has no effect if
  15057. logging is disabled.
  15058. Defaults to @samp{#f}.
  15059. @end deftypevr
  15060. @deftypevr {@code{opendht-configuration} parameter} maybe-string bootstrap-host
  15061. The node host name that is used to make the first connection to the
  15062. network. A specific port value can be provided by appending the
  15063. @code{:PORT} suffix. By default, it uses the Jami bootstrap nodes, but
  15064. any host can be specified here. It's also possible to disable
  15065. bootsrapping by setting this to the @code{'disabled} symbol.
  15066. Defaults to @samp{"bootstrap.jami.net:4222"}.
  15067. @end deftypevr
  15068. @deftypevr {@code{opendht-configuration} parameter} maybe-number port
  15069. The UDP port to bind to. When set to @code{'disabled}, an available
  15070. port is automatically selected.
  15071. Defaults to @samp{4222}.
  15072. @end deftypevr
  15073. @deftypevr {@code{opendht-configuration} parameter} maybe-number proxy-server-port
  15074. Spawn a proxy server listening on the specified port.
  15075. Defaults to @samp{disabled}.
  15076. @end deftypevr
  15077. @deftypevr {@code{opendht-configuration} parameter} maybe-number proxy-server-port-tls
  15078. Spawn a proxy server listening to TLS connections on the specified port.
  15079. Defaults to @samp{disabled}.
  15080. @end deftypevr
  15081. @end deftp
  15082. @cindex Tor
  15083. @defvr {Scheme Variable} tor-service-type
  15084. This is the type for a service that runs the @uref{https://torproject.org,
  15085. Tor} anonymous networking daemon. The service is configured using a
  15086. @code{<tor-configuration>} record. By default, the Tor daemon runs as the
  15087. @code{tor} unprivileged user, which is a member of the @code{tor} group.
  15088. @end defvr
  15089. @deftp {Data Type} tor-configuration
  15090. @table @asis
  15091. @item @code{tor} (default: @code{tor})
  15092. The package that provides the Tor daemon. This package is expected to provide
  15093. the daemon at @file{bin/tor} relative to its output directory. The default
  15094. package is the @uref{https://www.torproject.org, Tor Project's}
  15095. implementation.
  15096. @item @code{config-file} (default: @code{(plain-file "empty" "")})
  15097. The configuration file to use. It will be appended to a default configuration
  15098. file, and the final configuration file will be passed to @code{tor} via its
  15099. @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
  15100. file-like objects}). See @code{man tor} for details on the configuration file
  15101. syntax.
  15102. @item @code{hidden-services} (default: @code{'()})
  15103. The list of @code{<hidden-service>} records to use. For any hidden service
  15104. you include in this list, appropriate configuration to enable the hidden
  15105. service will be automatically added to the default configuration file. You
  15106. may conveniently create @code{<hidden-service>} records using the
  15107. @code{tor-hidden-service} procedure described below.
  15108. @item @code{socks-socket-type} (default: @code{'tcp})
  15109. The default socket type that Tor should use for its SOCKS socket. This must
  15110. be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
  15111. Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
  15112. If it is @code{'unix}, then Tor will listen on the UNIX domain socket
  15113. @file{/var/run/tor/socks-sock}, which will be made writable by members of the
  15114. @code{tor} group.
  15115. If you want to customize the SOCKS socket in more detail, leave
  15116. @code{socks-socket-type} at its default value of @code{'tcp} and use
  15117. @code{config-file} to override the default by providing your own
  15118. @code{SocksPort} option.
  15119. @item @code{control-socket?} (default: @code{#f})
  15120. Whether or not to provide a ``control socket'' by which Tor can be
  15121. controlled to, for instance, dynamically instantiate tor onion services.
  15122. If @code{#t}, Tor will listen for control commands on the UNIX domain socket
  15123. @file{/var/run/tor/control-sock}, which will be made writable by members of the
  15124. @code{tor} group.
  15125. @end table
  15126. @end deftp
  15127. @cindex hidden service
  15128. @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
  15129. Define a new Tor @dfn{hidden service} called @var{name} and implementing
  15130. @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
  15131. @example
  15132. '((22 "127.0.0.1:22")
  15133. (80 "127.0.0.1:8080"))
  15134. @end example
  15135. In this example, port 22 of the hidden service is mapped to local port 22, and
  15136. port 80 is mapped to local port 8080.
  15137. This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
  15138. the @file{hostname} file contains the @code{.onion} host name for the hidden
  15139. service.
  15140. See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
  15141. project's documentation} for more information.
  15142. @end deffn
  15143. The @code{(gnu services rsync)} module provides the following services:
  15144. You might want an rsync daemon if you have files that you want available
  15145. so anyone (or just yourself) can download existing files or upload new
  15146. files.
  15147. @deffn {Scheme Variable} rsync-service-type
  15148. This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
  15149. The value for this service type is a
  15150. @command{rsync-configuration} record as in this example:
  15151. @lisp
  15152. ;; Export two directories over rsync. By default rsync listens on
  15153. ;; all the network interfaces.
  15154. (service rsync-service-type
  15155. (rsync-configuration
  15156. (modules (list (rsync-module
  15157. (name "music")
  15158. (file-name "/srv/zik")
  15159. (read-only? #f))
  15160. (rsync-module
  15161. (name "movies")
  15162. (file-name "/home/charlie/movies"))))))
  15163. @end lisp
  15164. See below for details about @code{rsync-configuration}.
  15165. @end deffn
  15166. @deftp {Data Type} rsync-configuration
  15167. Data type representing the configuration for @code{rsync-service}.
  15168. @table @asis
  15169. @item @code{package} (default: @var{rsync})
  15170. @code{rsync} package to use.
  15171. @item @code{address} (default: @code{#f})
  15172. IP address on which @command{rsync} listens for incoming connections.
  15173. If unspecified, it defaults to listening on all available addresses.
  15174. @item @code{port-number} (default: @code{873})
  15175. TCP port on which @command{rsync} listens for incoming connections. If port
  15176. is less than @code{1024} @command{rsync} needs to be started as the
  15177. @code{root} user and group.
  15178. @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
  15179. Name of the file where @command{rsync} writes its PID.
  15180. @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
  15181. Name of the file where @command{rsync} writes its lock file.
  15182. @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
  15183. Name of the file where @command{rsync} writes its log file.
  15184. @item @code{user} (default: @code{"root"})
  15185. Owner of the @code{rsync} process.
  15186. @item @code{group} (default: @code{"root"})
  15187. Group of the @code{rsync} process.
  15188. @item @code{uid} (default: @code{"rsyncd"})
  15189. User name or user ID that file transfers to and from that module should take
  15190. place as when the daemon was run as @code{root}.
  15191. @item @code{gid} (default: @code{"rsyncd"})
  15192. Group name or group ID that will be used when accessing the module.
  15193. @item @code{modules} (default: @code{%default-modules})
  15194. List of ``modules''---i.e., directories exported over rsync. Each
  15195. element must be a @code{rsync-module} record, as described below.
  15196. @end table
  15197. @end deftp
  15198. @deftp {Data Type} rsync-module
  15199. This is the data type for rsync ``modules''. A module is a directory
  15200. exported over the rsync protocol. The available fields are as follows:
  15201. @table @asis
  15202. @item @code{name}
  15203. The module name. This is the name that shows up in URLs. For example,
  15204. if the module is called @code{music}, the corresponding URL will be
  15205. @code{rsync://host.example.org/music}.
  15206. @item @code{file-name}
  15207. Name of the directory being exported.
  15208. @item @code{comment} (default: @code{""})
  15209. Comment associated with the module. Client user interfaces may display
  15210. it when they obtain the list of available modules.
  15211. @item @code{read-only?} (default: @code{#t})
  15212. Whether or not client will be able to upload files. If this is false,
  15213. the uploads will be authorized if permissions on the daemon side permit
  15214. it.
  15215. @item @code{chroot?} (default: @code{#t})
  15216. When this is true, the rsync daemon changes root to the module's
  15217. directory before starting file transfers with the client. This improves
  15218. security, but requires rsync to run as root.
  15219. @item @code{timeout} (default: @code{300})
  15220. Idle time in seconds after which the daemon closes a connection with the
  15221. client.
  15222. @end table
  15223. @end deftp
  15224. The @code{(gnu services syncthing)} module provides the following services:
  15225. @cindex syncthing
  15226. You might want a syncthing daemon if you have files between two or more
  15227. computers and want to sync them in real time, safely protected from
  15228. prying eyes.
  15229. @deffn {Scheme Variable} syncthing-service-type
  15230. This is the service type for the @uref{https://syncthing.net/,
  15231. syncthing} daemon, The value for this service type is a
  15232. @command{syncthing-configuration} record as in this example:
  15233. @lisp
  15234. (service syncthing-service-type
  15235. (syncthing-configuration (user "alice")))
  15236. @end lisp
  15237. See below for details about @code{syncthing-configuration}.
  15238. @deftp {Data Type} syncthing-configuration
  15239. Data type representing the configuration for @code{syncthing-service-type}.
  15240. @table @asis
  15241. @item @code{syncthing} (default: @var{syncthing})
  15242. @code{syncthing} package to use.
  15243. @item @code{arguments} (default: @var{'()})
  15244. List of command-line arguments passing to @code{syncthing} binary.
  15245. @item @code{logflags} (default: @var{0})
  15246. Sum of logging flags, see
  15247. @uref{https://docs.syncthing.net/users/syncthing.html#cmdoption-logflags, Syncthing documentation logflags}.
  15248. @item @code{user} (default: @var{#f})
  15249. The user as which the Syncthing service is to be run.
  15250. This assumes that the specified user exists.
  15251. @item @code{group} (default: @var{"users"})
  15252. The group as which the Syncthing service is to be run.
  15253. This assumes that the specified group exists.
  15254. @item @code{home} (default: @var{#f})
  15255. Common configuration and data directory. The default configuration
  15256. directory is @file{$HOME} of the specified Syncthing @code{user}.
  15257. @end table
  15258. @end deftp
  15259. @end deffn
  15260. Furthermore, @code{(gnu services ssh)} provides the following services.
  15261. @cindex SSH
  15262. @cindex SSH server
  15263. @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
  15264. [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
  15265. [#:allow-empty-passwords? #f] [#:root-login? #f] @
  15266. [#:syslog-output? #t] [#:x11-forwarding? #t] @
  15267. [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
  15268. [#:public-key-authentication? #t] [#:initialize? #t]
  15269. Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
  15270. @var{host-key} must designate a file containing the host key, and readable
  15271. only by root.
  15272. When @var{daemonic?} is true, @command{lshd} will detach from the
  15273. controlling terminal and log its output to syslogd, unless one sets
  15274. @var{syslog-output?} to false. Obviously, it also makes lsh-service
  15275. depend on existence of syslogd service. When @var{pid-file?} is true,
  15276. @command{lshd} writes its PID to the file called @var{pid-file}.
  15277. When @var{initialize?} is true, automatically create the seed and host key
  15278. upon service activation if they do not exist yet. This may take long and
  15279. require interaction.
  15280. When @var{initialize?} is false, it is up to the user to initialize the
  15281. randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
  15282. a key pair with the private key stored in file @var{host-key} (@pxref{lshd
  15283. basics,,, lsh, LSH Manual}).
  15284. When @var{interfaces} is empty, lshd listens for connections on all the
  15285. network interfaces; otherwise, @var{interfaces} must be a list of host names
  15286. or addresses.
  15287. @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
  15288. passwords, and @var{root-login?} specifies whether to accept log-ins as
  15289. root.
  15290. The other options should be self-descriptive.
  15291. @end deffn
  15292. @cindex SSH
  15293. @cindex SSH server
  15294. @deffn {Scheme Variable} openssh-service-type
  15295. This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
  15296. shell daemon, @command{sshd}. Its value must be an
  15297. @code{openssh-configuration} record as in this example:
  15298. @lisp
  15299. (service openssh-service-type
  15300. (openssh-configuration
  15301. (x11-forwarding? #t)
  15302. (permit-root-login 'prohibit-password)
  15303. (authorized-keys
  15304. `(("alice" ,(local-file "alice.pub"))
  15305. ("bob" ,(local-file "bob.pub"))))))
  15306. @end lisp
  15307. See below for details about @code{openssh-configuration}.
  15308. This service can be extended with extra authorized keys, as in this
  15309. example:
  15310. @lisp
  15311. (service-extension openssh-service-type
  15312. (const `(("charlie"
  15313. ,(local-file "charlie.pub")))))
  15314. @end lisp
  15315. @end deffn
  15316. @deftp {Data Type} openssh-configuration
  15317. This is the configuration record for OpenSSH's @command{sshd}.
  15318. @table @asis
  15319. @item @code{openssh} (default @var{openssh})
  15320. The OpenSSH package to use.
  15321. @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
  15322. Name of the file where @command{sshd} writes its PID.
  15323. @item @code{port-number} (default: @code{22})
  15324. TCP port on which @command{sshd} listens for incoming connections.
  15325. @item @code{max-connections} (default: @code{200})
  15326. Hard limit on the maximum number of simultaneous client connections,
  15327. enforced by the inetd-style Shepherd service (@pxref{Service De- and
  15328. Constructors, @code{make-inetd-constructor},, shepherd, The GNU Shepherd
  15329. Manual}).
  15330. @item @code{permit-root-login} (default: @code{#f})
  15331. This field determines whether and when to allow logins as root. If
  15332. @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
  15333. If it's the symbol @code{'prohibit-password}, then root logins are
  15334. permitted but not with password-based authentication.
  15335. @item @code{allow-empty-passwords?} (default: @code{#f})
  15336. When true, users with empty passwords may log in. When false, they may
  15337. not.
  15338. @item @code{password-authentication?} (default: @code{#t})
  15339. When true, users may log in with their password. When false, they have
  15340. other authentication methods.
  15341. @item @code{public-key-authentication?} (default: @code{#t})
  15342. When true, users may log in using public key authentication. When
  15343. false, users have to use other authentication method.
  15344. Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
  15345. This is used only by protocol version 2.
  15346. @item @code{x11-forwarding?} (default: @code{#f})
  15347. When true, forwarding of X11 graphical client connections is
  15348. enabled---in other words, @command{ssh} options @option{-X} and
  15349. @option{-Y} will work.
  15350. @item @code{allow-agent-forwarding?} (default: @code{#t})
  15351. Whether to allow agent forwarding.
  15352. @item @code{allow-tcp-forwarding?} (default: @code{#t})
  15353. Whether to allow TCP forwarding.
  15354. @item @code{gateway-ports?} (default: @code{#f})
  15355. Whether to allow gateway ports.
  15356. @item @code{challenge-response-authentication?} (default: @code{#f})
  15357. Specifies whether challenge response authentication is allowed (e.g.@: via
  15358. PAM).
  15359. @item @code{use-pam?} (default: @code{#t})
  15360. Enables the Pluggable Authentication Module interface. If set to
  15361. @code{#t}, this will enable PAM authentication using
  15362. @code{challenge-response-authentication?} and
  15363. @code{password-authentication?}, in addition to PAM account and session
  15364. module processing for all authentication types.
  15365. Because PAM challenge response authentication usually serves an
  15366. equivalent role to password authentication, you should disable either
  15367. @code{challenge-response-authentication?} or
  15368. @code{password-authentication?}.
  15369. @item @code{print-last-log?} (default: @code{#t})
  15370. Specifies whether @command{sshd} should print the date and time of the
  15371. last user login when a user logs in interactively.
  15372. @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
  15373. Configures external subsystems (e.g.@: file transfer daemon).
  15374. This is a list of two-element lists, each of which containing the
  15375. subsystem name and a command (with optional arguments) to execute upon
  15376. subsystem request.
  15377. The command @command{internal-sftp} implements an in-process SFTP
  15378. server. Alternatively, one can specify the @command{sftp-server} command:
  15379. @lisp
  15380. (service openssh-service-type
  15381. (openssh-configuration
  15382. (subsystems
  15383. `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
  15384. @end lisp
  15385. @item @code{accepted-environment} (default: @code{'()})
  15386. List of strings describing which environment variables may be exported.
  15387. Each string gets on its own line. See the @code{AcceptEnv} option in
  15388. @code{man sshd_config}.
  15389. This example allows ssh-clients to export the @env{COLORTERM} variable.
  15390. It is set by terminal emulators, which support colors. You can use it in
  15391. your shell's resource file to enable colors for the prompt and commands
  15392. if this variable is set.
  15393. @lisp
  15394. (service openssh-service-type
  15395. (openssh-configuration
  15396. (accepted-environment '("COLORTERM"))))
  15397. @end lisp
  15398. @item @code{authorized-keys} (default: @code{'()})
  15399. @cindex authorized keys, SSH
  15400. @cindex SSH authorized keys
  15401. This is the list of authorized keys. Each element of the list is a user
  15402. name followed by one or more file-like objects that represent SSH public
  15403. keys. For example:
  15404. @lisp
  15405. (openssh-configuration
  15406. (authorized-keys
  15407. `(("rekado" ,(local-file "rekado.pub"))
  15408. ("chris" ,(local-file "chris.pub"))
  15409. ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
  15410. @end lisp
  15411. @noindent
  15412. registers the specified public keys for user accounts @code{rekado},
  15413. @code{chris}, and @code{root}.
  15414. Additional authorized keys can be specified @i{via}
  15415. @code{service-extension}.
  15416. Note that this does @emph{not} interfere with the use of
  15417. @file{~/.ssh/authorized_keys}.
  15418. @item @code{generate-host-keys?} (default: @code{#t})
  15419. Whether to generate host key pairs with @command{ssh-keygen -A} under
  15420. @file{/etc/ssh} if there are none.
  15421. Generating key pairs takes a few seconds when enough entropy is
  15422. available and is only done once. You might want to turn it off for
  15423. instance in a virtual machine that does not need it because host keys
  15424. are provided in some other way, and where the extra boot time is a
  15425. problem.
  15426. @item @code{log-level} (default: @code{'info})
  15427. This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
  15428. @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
  15429. page for @file{sshd_config} for the full list of level names.
  15430. @item @code{extra-content} (default: @code{""})
  15431. This field can be used to append arbitrary text to the configuration file. It
  15432. is especially useful for elaborate configurations that cannot be expressed
  15433. otherwise. This configuration, for example, would generally disable root
  15434. logins, but permit them from one specific IP address:
  15435. @lisp
  15436. (openssh-configuration
  15437. (extra-content "\
  15438. Match Address 192.168.0.1
  15439. PermitRootLogin yes"))
  15440. @end lisp
  15441. @end table
  15442. @end deftp
  15443. @deffn {Scheme Procedure} dropbear-service [@var{config}]
  15444. Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
  15445. daemon} with the given @var{config}, a @code{<dropbear-configuration>}
  15446. object.
  15447. For example, to specify a Dropbear service listening on port 1234, add
  15448. this call to the operating system's @code{services} field:
  15449. @lisp
  15450. (dropbear-service (dropbear-configuration
  15451. (port-number 1234)))
  15452. @end lisp
  15453. @end deffn
  15454. @deftp {Data Type} dropbear-configuration
  15455. This data type represents the configuration of a Dropbear SSH daemon.
  15456. @table @asis
  15457. @item @code{dropbear} (default: @var{dropbear})
  15458. The Dropbear package to use.
  15459. @item @code{port-number} (default: 22)
  15460. The TCP port where the daemon waits for incoming connections.
  15461. @item @code{syslog-output?} (default: @code{#t})
  15462. Whether to enable syslog output.
  15463. @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
  15464. File name of the daemon's PID file.
  15465. @item @code{root-login?} (default: @code{#f})
  15466. Whether to allow @code{root} logins.
  15467. @item @code{allow-empty-passwords?} (default: @code{#f})
  15468. Whether to allow empty passwords.
  15469. @item @code{password-authentication?} (default: @code{#t})
  15470. Whether to enable password-based authentication.
  15471. @end table
  15472. @end deftp
  15473. @cindex AutoSSH
  15474. @deffn {Scheme Variable} autossh-service-type
  15475. This is the type for the @uref{https://www.harding.motd.ca/autossh,
  15476. AutoSSH} program that runs a copy of @command{ssh} and monitors it,
  15477. restarting it as necessary should it die or stop passing traffic.
  15478. AutoSSH can be run manually from the command-line by passing arguments
  15479. to the binary @command{autossh} from the package @code{autossh}, but it
  15480. can also be run as a Guix service. This latter use case is documented
  15481. here.
  15482. AutoSSH can be used to forward local traffic to a remote machine using
  15483. an SSH tunnel, and it respects the @file{~/.ssh/config} of the user it
  15484. is run as.
  15485. For example, to specify a service running autossh as the user
  15486. @code{pino} and forwarding all local connections to port @code{8081} to
  15487. @code{remote:8081} using an SSH tunnel, add this call to the operating
  15488. system's @code{services} field:
  15489. @lisp
  15490. (service autossh-service-type
  15491. (autossh-configuration
  15492. (user "pino")
  15493. (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
  15494. @end lisp
  15495. @end deffn
  15496. @deftp {Data Type} autossh-configuration
  15497. This data type represents the configuration of an AutoSSH service.
  15498. @table @asis
  15499. @item @code{user} (default @code{"autossh"})
  15500. The user as which the AutoSSH service is to be run.
  15501. This assumes that the specified user exists.
  15502. @item @code{poll} (default @code{600})
  15503. Specifies the connection poll time in seconds.
  15504. @item @code{first-poll} (default @code{#f})
  15505. Specifies how many seconds AutoSSH waits before the first connection
  15506. test. After this first test, polling is resumed at the pace defined in
  15507. @code{poll}. When set to @code{#f}, the first poll is not treated
  15508. specially and will also use the connection poll specified in
  15509. @code{poll}.
  15510. @item @code{gate-time} (default @code{30})
  15511. Specifies how many seconds an SSH connection must be active before it is
  15512. considered successful.
  15513. @item @code{log-level} (default @code{1})
  15514. The log level, corresponding to the levels used by syslog---so @code{0}
  15515. is the most silent while @code{7} is the chattiest.
  15516. @item @code{max-start} (default @code{#f})
  15517. The maximum number of times SSH may be (re)started before AutoSSH exits.
  15518. When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
  15519. @item @code{message} (default @code{""})
  15520. The message to append to the echo message sent when testing connections.
  15521. @item @code{port} (default @code{"0"})
  15522. The ports used for monitoring the connection. When set to @code{"0"},
  15523. monitoring is disabled. When set to @code{"@var{n}"} where @var{n} is
  15524. a positive integer, ports @var{n} and @var{n}+1 are used for
  15525. monitoring the connection, such that port @var{n} is the base
  15526. monitoring port and @code{n+1} is the echo port. When set to
  15527. @code{"@var{n}:@var{m}"} where @var{n} and @var{m} are positive
  15528. integers, the ports @var{n} and @var{m} are used for monitoring the
  15529. connection, such that port @var{n} is the base monitoring port and
  15530. @var{m} is the echo port.
  15531. @item @code{ssh-options} (default @code{'()})
  15532. The list of command-line arguments to pass to @command{ssh} when it is
  15533. run. Options @option{-f} and @option{-M} are reserved for AutoSSH and
  15534. may cause undefined behaviour.
  15535. @end table
  15536. @end deftp
  15537. @cindex WebSSH
  15538. @deffn {Scheme Variable} webssh-service-type
  15539. This is the type for the @uref{https://webssh.huashengdun.org/, WebSSH}
  15540. program that runs a web SSH client. WebSSH can be run manually from the
  15541. command-line by passing arguments to the binary @command{wssh} from the
  15542. package @code{webssh}, but it can also be run as a Guix service. This
  15543. latter use case is documented here.
  15544. For example, to specify a service running WebSSH on loopback interface
  15545. on port @code{8888} with reject policy with a list of allowed to
  15546. connection hosts, and NGINX as a reverse-proxy to this service listening
  15547. for HTTPS connection, add this call to the operating system's
  15548. @code{services} field:
  15549. @lisp
  15550. (service webssh-service-type
  15551. (webssh-configuration (address "127.0.0.1")
  15552. (port 8888)
  15553. (policy 'reject)
  15554. (known-hosts '("localhost ecdsa-sha2-nistp256 AAAA…"
  15555. "127.0.0.1 ecdsa-sha2-nistp256 AAAA…"))))
  15556. (service nginx-service-type
  15557. (nginx-configuration
  15558. (server-blocks
  15559. (list
  15560. (nginx-server-configuration
  15561. (inherit %webssh-configuration-nginx)
  15562. (server-name '("webssh.example.com"))
  15563. (listen '("443 ssl"))
  15564. (ssl-certificate (letsencrypt-certificate "webssh.example.com"))
  15565. (ssl-certificate-key (letsencrypt-key "webssh.example.com"))
  15566. (locations
  15567. (cons (nginx-location-configuration
  15568. (uri "/.well-known")
  15569. (body '("root /var/www;")))
  15570. (nginx-server-configuration-locations %webssh-configuration-nginx))))))))
  15571. @end lisp
  15572. @end deffn
  15573. @deftp {Data Type} webssh-configuration
  15574. Data type representing the configuration for @code{webssh-service}.
  15575. @table @asis
  15576. @item @code{package} (default: @var{webssh})
  15577. @code{webssh} package to use.
  15578. @item @code{user-name} (default: @var{"webssh"})
  15579. User name or user ID that file transfers to and from that module should take
  15580. place.
  15581. @item @code{group-name} (default: @var{"webssh"})
  15582. Group name or group ID that will be used when accessing the module.
  15583. @item @code{address} (default: @var{#f})
  15584. IP address on which @command{webssh} listens for incoming connections.
  15585. @item @code{port} (default: @var{8888})
  15586. TCP port on which @command{webssh} listens for incoming connections.
  15587. @item @code{policy} (default: @var{#f})
  15588. Connection policy. @var{reject} policy requires to specify @var{known-hosts}.
  15589. @item @code{known-hosts} (default: @var{'()})
  15590. List of hosts which allowed for SSH connection from @command{webssh}.
  15591. @item @code{log-file} (default: @file{"/var/log/webssh.log"})
  15592. Name of the file where @command{webssh} writes its log file.
  15593. @item @code{log-level} (default: @var{#f})
  15594. Logging level.
  15595. @end table
  15596. @end deftp
  15597. @defvr {Scheme Variable} %facebook-host-aliases
  15598. This variable contains a string for use in @file{/etc/hosts}
  15599. (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
  15600. line contains a entry that maps a known server name of the Facebook
  15601. on-line service---e.g., @code{www.facebook.com}---to the local
  15602. host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
  15603. This variable is typically used in the @code{hosts-file} field of an
  15604. @code{operating-system} declaration (@pxref{operating-system Reference,
  15605. @file{/etc/hosts}}):
  15606. @lisp
  15607. (use-modules (gnu) (guix))
  15608. (operating-system
  15609. (host-name "mymachine")
  15610. ;; ...
  15611. (hosts-file
  15612. ;; Create a /etc/hosts file with aliases for "localhost"
  15613. ;; and "mymachine", as well as for Facebook servers.
  15614. (plain-file "hosts"
  15615. (string-append (local-host-aliases host-name)
  15616. %facebook-host-aliases))))
  15617. @end lisp
  15618. This mechanism can prevent programs running locally, such as Web
  15619. browsers, from accessing Facebook.
  15620. @end defvr
  15621. The @code{(gnu services avahi)} provides the following definition.
  15622. @defvr {Scheme Variable} avahi-service-type
  15623. This is the service that runs @command{avahi-daemon}, a system-wide
  15624. mDNS/DNS-SD responder that allows for service discovery and
  15625. ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
  15626. Its value must be an @code{avahi-configuration} record---see below.
  15627. This service extends the name service cache daemon (nscd) so that it can
  15628. resolve @code{.local} host names using
  15629. @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
  15630. Service Switch}, for information on host name resolution.
  15631. Additionally, add the @var{avahi} package to the system profile so that
  15632. commands such as @command{avahi-browse} are directly usable.
  15633. @end defvr
  15634. @deftp {Data Type} avahi-configuration
  15635. Data type representation the configuration for Avahi.
  15636. @table @asis
  15637. @item @code{host-name} (default: @code{#f})
  15638. If different from @code{#f}, use that as the host name to
  15639. publish for this machine; otherwise, use the machine's actual host name.
  15640. @item @code{publish?} (default: @code{#t})
  15641. When true, allow host names and services to be published (broadcast) over the
  15642. network.
  15643. @item @code{publish-workstation?} (default: @code{#t})
  15644. When true, @command{avahi-daemon} publishes the machine's host name and IP
  15645. address via mDNS on the local network. To view the host names published on
  15646. your local network, you can run:
  15647. @example
  15648. avahi-browse _workstation._tcp
  15649. @end example
  15650. @item @code{wide-area?} (default: @code{#f})
  15651. When true, DNS-SD over unicast DNS is enabled.
  15652. @item @code{ipv4?} (default: @code{#t})
  15653. @itemx @code{ipv6?} (default: @code{#t})
  15654. These fields determine whether to use IPv4/IPv6 sockets.
  15655. @item @code{domains-to-browse} (default: @code{'()})
  15656. This is a list of domains to browse.
  15657. @end table
  15658. @end deftp
  15659. @deffn {Scheme Variable} openvswitch-service-type
  15660. This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
  15661. service, whose value should be an @code{openvswitch-configuration}
  15662. object.
  15663. @end deffn
  15664. @deftp {Data Type} openvswitch-configuration
  15665. Data type representing the configuration of Open vSwitch, a multilayer
  15666. virtual switch which is designed to enable massive network automation
  15667. through programmatic extension.
  15668. @table @asis
  15669. @item @code{package} (default: @var{openvswitch})
  15670. Package object of the Open vSwitch.
  15671. @end table
  15672. @end deftp
  15673. @defvr {Scheme Variable} pagekite-service-type
  15674. This is the service type for the @uref{https://pagekite.net, PageKite} service,
  15675. a tunneling solution for making localhost servers publicly visible, even from
  15676. behind restrictive firewalls or NAT without forwarded ports. The value for
  15677. this service type is a @code{pagekite-configuration} record.
  15678. Here's an example exposing the local HTTP and SSH daemons:
  15679. @lisp
  15680. (service pagekite-service-type
  15681. (pagekite-configuration
  15682. (kites '("http:@@kitename:localhost:80:@@kitesecret"
  15683. "raw/22:@@kitename:localhost:22:@@kitesecret"))
  15684. (extra-file "/etc/pagekite.rc")))
  15685. @end lisp
  15686. @end defvr
  15687. @deftp {Data Type} pagekite-configuration
  15688. Data type representing the configuration of PageKite.
  15689. @table @asis
  15690. @item @code{package} (default: @var{pagekite})
  15691. Package object of PageKite.
  15692. @item @code{kitename} (default: @code{#f})
  15693. PageKite name for authenticating to the frontend server.
  15694. @item @code{kitesecret} (default: @code{#f})
  15695. Shared secret for authenticating to the frontend server. You should probably
  15696. put this inside @code{extra-file} instead.
  15697. @item @code{frontend} (default: @code{#f})
  15698. Connect to the named PageKite frontend server instead of the
  15699. @uref{https://pagekite.net,,pagekite.net} service.
  15700. @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
  15701. List of service kites to use. Exposes HTTP on port 80 by default. The format
  15702. is @code{proto:kitename:host:port:secret}.
  15703. @item @code{extra-file} (default: @code{#f})
  15704. Extra configuration file to read, which you are expected to create manually.
  15705. Use this to add additional options and manage shared secrets out-of-band.
  15706. @end table
  15707. @end deftp
  15708. @defvr {Scheme Variable} yggdrasil-service-type
  15709. The service type for connecting to the @uref{https://yggdrasil-network.github.io/,
  15710. Yggdrasil network}, an early-stage implementation of a fully end-to-end
  15711. encrypted IPv6 network.
  15712. @quotation
  15713. Yggdrasil provides name-independent routing with cryptographically generated
  15714. addresses. Static addressing means you can keep the same address as long as
  15715. you want, even if you move to a new location, or generate a new address (by
  15716. generating new keys) whenever you want.
  15717. @uref{https://yggdrasil-network.github.io/2018/07/28/addressing.html}
  15718. @end quotation
  15719. Pass it a value of @code{yggdrasil-configuration} to connect it to public
  15720. peers and/or local peers.
  15721. Here is an example using public peers and a static address. The static
  15722. signing and encryption keys are defined in @file{/etc/yggdrasil-private.conf}
  15723. (the default value for @code{config-file}).
  15724. @lisp
  15725. ;; part of the operating-system declaration
  15726. (service yggdrasil-service-type
  15727. (yggdrasil-configuration
  15728. (autoconf? #f) ;; use only the public peers
  15729. (json-config
  15730. ;; choose one from
  15731. ;; https://github.com/yggdrasil-network/public-peers
  15732. '((peers . #("tcp://1.2.3.4:1337"))))
  15733. ;; /etc/yggdrasil-private.conf is the default value for config-file
  15734. ))
  15735. @end lisp
  15736. @example
  15737. # sample content for /etc/yggdrasil-private.conf
  15738. @{
  15739. # Your public key. Your peers may ask you for this to put
  15740. # into their AllowedPublicKeys configuration.
  15741. PublicKey: 64277...
  15742. # Your private key. DO NOT share this with anyone!
  15743. PrivateKey: 5c750...
  15744. @}
  15745. @end example
  15746. @end defvr
  15747. @deftp {Data Type} yggdrasil-configuration
  15748. Data type representing the configuration of Yggdrasil.
  15749. @table @asis
  15750. @item @code{package} (default: @code{yggdrasil})
  15751. Package object of Yggdrasil.
  15752. @item @code{json-config} (default: @code{'()})
  15753. Contents of @file{/etc/yggdrasil.conf}. Will be merged with
  15754. @file{/etc/yggdrasil-private.conf}. Note that these settings are stored in
  15755. the Guix store, which is readable to all users. @strong{Do not store your
  15756. private keys in it}. See the output of @code{yggdrasil -genconf} for a
  15757. quick overview of valid keys and their default values.
  15758. @item @code{autoconf?} (default: @code{#f})
  15759. Whether to use automatic mode. Enabling it makes Yggdrasil use adynamic IP
  15760. and peer with IPv6 neighbors.
  15761. @item @code{log-level} (default: @code{'info})
  15762. How much detail to include in logs. Use @code{'debug} for more detail.
  15763. @item @code{log-to} (default: @code{'stdout})
  15764. Where to send logs. By default, the service logs standard output to
  15765. @file{/var/log/yggdrasil.log}. The alternative is @code{'syslog}, which
  15766. sends output to the running syslog service.
  15767. @item @code{config-file} (default: @code{"/etc/yggdrasil-private.conf"})
  15768. What HJSON file to load sensitive data from. This is where private keys
  15769. should be stored, which are necessary to specify if you don't want a
  15770. randomized address after each restart. Use @code{#f} to disable. Options
  15771. defined in this file take precedence over @code{json-config}. Use the output
  15772. of @code{yggdrasil -genconf} as a starting point. To configure a static
  15773. address, delete everything except these options:
  15774. @itemize
  15775. @item @code{EncryptionPublicKey}
  15776. @item @code{EncryptionPrivateKey}
  15777. @item @code{SigningPublicKey}
  15778. @item @code{SigningPrivateKey}
  15779. @end itemize
  15780. @end table
  15781. @end deftp
  15782. @cindex IPFS
  15783. @defvr {Scheme Variable} ipfs-service-type
  15784. The service type for connecting to the @uref{https://ipfs.io,IPFS network},
  15785. a global, versioned, peer-to-peer file system. Pass it a
  15786. @code{ipfs-configuration} to change the ports used for the gateway and API.
  15787. Here's an example configuration, using some non-standard ports:
  15788. @lisp
  15789. (service ipfs-service-type
  15790. (ipfs-configuration
  15791. (gateway "/ip4/127.0.0.1/tcp/8880")
  15792. (api "/ip4/127.0.0.1/tcp/8881")))
  15793. @end lisp
  15794. @end defvr
  15795. @deftp {Data Type} ipfs-configuration
  15796. Data type representing the configuration of IPFS.
  15797. @table @asis
  15798. @item @code{package} (default: @code{go-ipfs})
  15799. Package object of IPFS.
  15800. @item @code{gateway} (default: @code{"/ip4/127.0.0.1/tcp/8082"})
  15801. Address of the gateway, in ‘multiaddress’ format.
  15802. @item @code{api} (default: @code{"/ip4/127.0.0.1/tcp/5001"})
  15803. Address of the API endpoint, in ‘multiaddress’ format.
  15804. @end table
  15805. @end deftp
  15806. @cindex keepalived
  15807. @deffn {Scheme Variable} keepalived-service-type
  15808. This is the type for the @uref{https://www.keepalived.org/, Keepalived}
  15809. routing software, @command{keepalived}. Its value must be an
  15810. @code{keepalived-configuration} record as in this example for master
  15811. machine:
  15812. @lisp
  15813. (service keepalived-service-type
  15814. (keepalived-configuration
  15815. (config-file (local-file "keepalived-master.conf"))))
  15816. @end lisp
  15817. where @file{keepalived-master.conf}:
  15818. @example
  15819. vrrp_instance my-group @{
  15820. state MASTER
  15821. interface enp9s0
  15822. virtual_router_id 100
  15823. priority 100
  15824. unicast_peer @{ 10.0.0.2 @}
  15825. virtual_ipaddress @{
  15826. 10.0.0.4/24
  15827. @}
  15828. @}
  15829. @end example
  15830. and for backup machine:
  15831. @lisp
  15832. (service keepalived-service-type
  15833. (keepalived-configuration
  15834. (config-file (local-file "keepalived-backup.conf"))))
  15835. @end lisp
  15836. where @file{keepalived-backup.conf}:
  15837. @example
  15838. vrrp_instance my-group @{
  15839. state BACKUP
  15840. interface enp9s0
  15841. virtual_router_id 100
  15842. priority 99
  15843. unicast_peer @{ 10.0.0.3 @}
  15844. virtual_ipaddress @{
  15845. 10.0.0.4/24
  15846. @}
  15847. @}
  15848. @end example
  15849. @end deffn
  15850. @node Unattended Upgrades
  15851. @subsection Unattended Upgrades
  15852. @cindex unattended upgrades
  15853. @cindex upgrades, unattended
  15854. Guix provides a service to perform @emph{unattended upgrades}:
  15855. periodically, the system automatically reconfigures itself from the
  15856. latest Guix. Guix System has several properties that make unattended
  15857. upgrades safe:
  15858. @itemize
  15859. @item
  15860. upgrades are transactional (either the upgrade succeeds or it fails, but
  15861. you cannot end up with an ``in-between'' system state);
  15862. @item
  15863. the upgrade log is kept---you can view it with @command{guix system
  15864. list-generations}---and you can roll back to any previous generation,
  15865. should the upgraded system fail to behave as intended;
  15866. @item
  15867. channel code is authenticated so you know you can only run genuine code
  15868. (@pxref{Channels});
  15869. @item
  15870. @command{guix system reconfigure} prevents downgrades, which makes it
  15871. immune to @dfn{downgrade attacks}.
  15872. @end itemize
  15873. To set up unattended upgrades, add an instance of
  15874. @code{unattended-upgrade-service-type} like the one below to the list of
  15875. your operating system services:
  15876. @lisp
  15877. (service unattended-upgrade-service-type)
  15878. @end lisp
  15879. The defaults above set up weekly upgrades: every Sunday at midnight.
  15880. You do not need to provide the operating system configuration file: it
  15881. uses @file{/run/current-system/configuration.scm}, which ensures it
  15882. always uses your latest configuration---@pxref{provenance-service-type},
  15883. for more information about this file.
  15884. There are several things that can be configured, in particular the
  15885. periodicity and services (daemons) to be restarted upon completion.
  15886. When the upgrade is successful, the service takes care of deleting
  15887. system generations older that some threshold, as per @command{guix
  15888. system delete-generations}. See the reference below for details.
  15889. To ensure that upgrades are actually happening, you can run
  15890. @command{guix system describe}. To investigate upgrade failures, visit
  15891. the unattended upgrade log file (see below).
  15892. @defvr {Scheme Variable} unattended-upgrade-service-type
  15893. This is the service type for unattended upgrades. It sets up an mcron
  15894. job (@pxref{Scheduled Job Execution}) that runs @command{guix system
  15895. reconfigure} from the latest version of the specified channels.
  15896. Its value must be a @code{unattended-upgrade-configuration} record (see
  15897. below).
  15898. @end defvr
  15899. @deftp {Data Type} unattended-upgrade-configuration
  15900. This data type represents the configuration of the unattended upgrade
  15901. service. The following fields are available:
  15902. @table @asis
  15903. @item @code{schedule} (default: @code{"30 01 * * 0"})
  15904. This is the schedule of upgrades, expressed as a gexp containing an
  15905. mcron job schedule (@pxref{Guile Syntax, mcron job specifications,,
  15906. mcron, GNU@tie{}mcron}).
  15907. @item @code{channels} (default: @code{#~%default-channels})
  15908. This gexp specifies the channels to use for the upgrade
  15909. (@pxref{Channels}). By default, the tip of the official @code{guix}
  15910. channel is used.
  15911. @item @code{operating-system-file} (default: @code{"/run/current-system/configuration.scm"})
  15912. This field specifies the operating system configuration file to use.
  15913. The default is to reuse the config file of the current configuration.
  15914. There are cases, though, where referring to
  15915. @file{/run/current-system/configuration.scm} is not enough, for instance
  15916. because that file refers to extra files (SSH public keys, extra
  15917. configuration files, etc.) @i{via} @code{local-file} and similar
  15918. constructs. For those cases, we recommend something along these lines:
  15919. @lisp
  15920. (unattended-upgrade-configuration
  15921. (operating-system-file
  15922. (file-append (local-file "." "config-dir" #:recursive? #t)
  15923. "/config.scm")))
  15924. @end lisp
  15925. The effect here is to import all of the current directory into the
  15926. store, and to refer to @file{config.scm} within that directory.
  15927. Therefore, uses of @code{local-file} within @file{config.scm} will work
  15928. as expected. @xref{G-Expressions}, for information about
  15929. @code{local-file} and @code{file-append}.
  15930. @item @code{services-to-restart} (default: @code{'(mcron)})
  15931. This field specifies the Shepherd services to restart when the upgrade
  15932. completes.
  15933. Those services are restarted right away upon completion, as with
  15934. @command{herd restart}, which ensures that the latest version is
  15935. running---remember that by default @command{guix system reconfigure}
  15936. only restarts services that are not currently running, which is
  15937. conservative: it minimizes disruption but leaves outdated services
  15938. running.
  15939. Use @command{herd status} to find out candidates for restarting.
  15940. @xref{Services}, for general information about services. Common
  15941. services to restart would include @code{ntpd} and @code{ssh-daemon}.
  15942. By default, the @code{mcron} service is restarted. This ensures that
  15943. the latest version of the unattended upgrade job will be used next time.
  15944. @item @code{system-expiration} (default: @code{(* 3 30 24 3600)})
  15945. This is the expiration time in seconds for system generations. System
  15946. generations older that this amount of time are deleted with
  15947. @command{guix system delete-generations} when an upgrade completes.
  15948. @quotation Note
  15949. The unattended upgrade service does not run the garbage collector. You
  15950. will probably want to set up your own mcron job to run @command{guix gc}
  15951. periodically.
  15952. @end quotation
  15953. @item @code{maximum-duration} (default: @code{3600})
  15954. Maximum duration in seconds for the upgrade; past that time, the upgrade
  15955. aborts.
  15956. This is primarily useful to ensure the upgrade does not end up
  15957. rebuilding or re-downloading ``the world''.
  15958. @item @code{log-file} (default: @code{"/var/log/unattended-upgrade.log"})
  15959. File where unattended upgrades are logged.
  15960. @end table
  15961. @end deftp
  15962. @node X Window
  15963. @subsection X Window
  15964. @cindex X11
  15965. @cindex X Window System
  15966. @cindex login manager
  15967. Support for the X Window graphical display system---specifically
  15968. Xorg---is provided by the @code{(gnu services xorg)} module. Note that
  15969. there is no @code{xorg-service} procedure. Instead, the X server is
  15970. started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
  15971. @cindex GDM
  15972. @cindex GNOME, login manager
  15973. GDM of course allows users to log in into window managers and desktop
  15974. environments other than GNOME; for those using GNOME, GDM is required for
  15975. features such as automatic screen locking.
  15976. @cindex window manager
  15977. To use X11, you must install at least one @dfn{window manager}---for
  15978. example the @code{windowmaker} or @code{openbox} packages---preferably
  15979. by adding it to the @code{packages} field of your operating system
  15980. definition (@pxref{operating-system Reference, system-wide packages}).
  15981. @anchor{wayland-gdm}
  15982. GDM also supports Wayland: it can itself use Wayland instead of X11 for
  15983. its user interface, and it can also start Wayland sessions. The former is
  15984. required for the latter, to enable, set @code{wayland?} to @code{#t} in
  15985. @code{gdm-configuration}.
  15986. @defvr {Scheme Variable} gdm-service-type
  15987. This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
  15988. Desktop Manager} (GDM), a program that manages graphical display servers and
  15989. handles graphical user logins. Its value must be a @code{gdm-configuration}
  15990. (see below).
  15991. @cindex session types
  15992. GDM looks for @dfn{session types} described by the @file{.desktop} files in
  15993. @file{/run/current-system/profile/share/xsessions} (for X11 sessions) and
  15994. @file{/run/current-system/profile/share/wayland-sessions} (for Wayland
  15995. sessions) and allows users to choose a session from the log-in screen.
  15996. Packages such as @code{gnome}, @code{xfce}, @code{i3} and @code{sway} provide
  15997. @file{.desktop} files; adding them to the system-wide set of packages
  15998. automatically makes them available at the log-in screen.
  15999. In addition, @file{~/.xsession} files are honored. When available,
  16000. @file{~/.xsession} must be an executable that starts a window manager
  16001. and/or other X clients.
  16002. @end defvr
  16003. @deftp {Data Type} gdm-configuration
  16004. @table @asis
  16005. @item @code{auto-login?} (default: @code{#f})
  16006. @itemx @code{default-user} (default: @code{#f})
  16007. When @code{auto-login?} is false, GDM presents a log-in screen.
  16008. When @code{auto-login?} is true, GDM logs in directly as
  16009. @code{default-user}.
  16010. @item @code{debug?} (default: @code{#f})
  16011. When true, GDM writes debug messages to its log.
  16012. @item @code{gnome-shell-assets} (default: ...)
  16013. List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
  16014. @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
  16015. Configuration of the Xorg graphical server.
  16016. @item @code{xsession} (default: @code{(xinitrc)})
  16017. Script to run before starting a X session.
  16018. @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
  16019. File name of the @code{dbus-daemon} executable.
  16020. @item @code{gdm} (default: @code{gdm})
  16021. The GDM package to use.
  16022. @item @code{wayland?} (default: @code{#f})
  16023. When true, enables Wayland in GDM, necessary to use Wayland sessions.
  16024. @item @code{wayland-session} (default: @code{gdm-wayland-session-wrapper})
  16025. The Wayland session wrapper to use, needed to setup the
  16026. environment.
  16027. @end table
  16028. @end deftp
  16029. @defvr {Scheme Variable} slim-service-type
  16030. This is the type for the SLiM graphical login manager for X11.
  16031. Like GDM, SLiM looks for session types described by @file{.desktop} files and
  16032. allows users to choose a session from the log-in screen using @kbd{F1}. It
  16033. also honors @file{~/.xsession} files.
  16034. Unlike GDM, SLiM does not spawn the user session on a different VT after
  16035. logging in, which means that you can only start one graphical session. If you
  16036. want to be able to run multiple graphical sessions at the same time you have
  16037. to add multiple SLiM services to your system services. The following example
  16038. shows how to replace the default GDM service with two SLiM services on tty7
  16039. and tty8.
  16040. @lisp
  16041. (use-modules (gnu services)
  16042. (gnu services desktop)
  16043. (gnu services xorg))
  16044. (operating-system
  16045. ;; ...
  16046. (services (cons* (service slim-service-type (slim-configuration
  16047. (display ":0")
  16048. (vt "vt7")))
  16049. (service slim-service-type (slim-configuration
  16050. (display ":1")
  16051. (vt "vt8")))
  16052. (modify-services %desktop-services
  16053. (delete gdm-service-type)))))
  16054. @end lisp
  16055. @end defvr
  16056. @deftp {Data Type} slim-configuration
  16057. Data type representing the configuration of @code{slim-service-type}.
  16058. @table @asis
  16059. @item @code{allow-empty-passwords?} (default: @code{#t})
  16060. Whether to allow logins with empty passwords.
  16061. @item @code{gnupg?} (default: @code{#f})
  16062. If enabled, @code{pam-gnupg} will attempt to automatically unlock the
  16063. user's GPG keys with the login password via @code{gpg-agent}. The
  16064. keygrips of all keys to be unlocked should be written to
  16065. @file{~/.pam-gnupg}, and can be queried with @code{gpg -K
  16066. --with-keygrip}. Presetting passphrases must be enabled by adding
  16067. @code{allow-preset-passphrase} in @file{~/.gnupg/gpg-agent.conf}.
  16068. @item @code{auto-login?} (default: @code{#f})
  16069. @itemx @code{default-user} (default: @code{""})
  16070. When @code{auto-login?} is false, SLiM presents a log-in screen.
  16071. When @code{auto-login?} is true, SLiM logs in directly as
  16072. @code{default-user}.
  16073. @item @code{theme} (default: @code{%default-slim-theme})
  16074. @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
  16075. The graphical theme to use and its name.
  16076. @item @code{auto-login-session} (default: @code{#f})
  16077. If true, this must be the name of the executable to start as the default
  16078. session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
  16079. If false, a session described by one of the available @file{.desktop}
  16080. files in @code{/run/current-system/profile} and @code{~/.guix-profile}
  16081. will be used.
  16082. @quotation Note
  16083. You must install at least one window manager in the system profile or in
  16084. your user profile. Failing to do that, if @code{auto-login-session} is
  16085. false, you will be unable to log in.
  16086. @end quotation
  16087. @item @code{xorg-configuration} (default @code{(xorg-configuration)})
  16088. Configuration of the Xorg graphical server.
  16089. @item @code{display} (default @code{":0"})
  16090. The display on which to start the Xorg graphical server.
  16091. @item @code{vt} (default @code{"vt7"})
  16092. The VT on which to start the Xorg graphical server.
  16093. @item @code{xauth} (default: @code{xauth})
  16094. The XAuth package to use.
  16095. @item @code{shepherd} (default: @code{shepherd})
  16096. The Shepherd package used when invoking @command{halt} and
  16097. @command{reboot}.
  16098. @item @code{sessreg} (default: @code{sessreg})
  16099. The sessreg package used in order to register the session.
  16100. @item @code{slim} (default: @code{slim})
  16101. The SLiM package to use.
  16102. @end table
  16103. @end deftp
  16104. @defvr {Scheme Variable} %default-theme
  16105. @defvrx {Scheme Variable} %default-theme-name
  16106. The default SLiM theme and its name.
  16107. @end defvr
  16108. @deftp {Data Type} sddm-configuration
  16109. This is the data type representing the SDDM service configuration.
  16110. @table @asis
  16111. @item @code{display-server} (default: "x11")
  16112. Select display server to use for the greeter. Valid values are
  16113. @samp{"x11"} or @samp{"wayland"}.
  16114. @item @code{numlock} (default: "on")
  16115. Valid values are @samp{"on"}, @samp{"off"} or @samp{"none"}.
  16116. @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
  16117. Command to run when halting.
  16118. @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
  16119. Command to run when rebooting.
  16120. @item @code{theme} (default "maldives")
  16121. Theme to use. Default themes provided by SDDM are @samp{"elarun"},
  16122. @samp{"maldives"} or @samp{"maya"}.
  16123. @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
  16124. Directory to look for themes.
  16125. @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
  16126. Directory to look for faces.
  16127. @item @code{default-path} (default "/run/current-system/profile/bin")
  16128. Default PATH to use.
  16129. @item @code{minimum-uid} (default: 1000)
  16130. Minimum UID displayed in SDDM and allowed for log-in.
  16131. @item @code{maximum-uid} (default: 2000)
  16132. Maximum UID to display in SDDM.
  16133. @item @code{remember-last-user?} (default #t)
  16134. Remember last user.
  16135. @item @code{remember-last-session?} (default #t)
  16136. Remember last session.
  16137. @item @code{hide-users} (default "")
  16138. Usernames to hide from SDDM greeter.
  16139. @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
  16140. Users with shells listed will be hidden from the SDDM greeter.
  16141. @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
  16142. Script to run before starting a wayland session.
  16143. @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
  16144. Directory to look for desktop files starting wayland sessions.
  16145. @item @code{xorg-configuration} (default @code{(xorg-configuration)})
  16146. Configuration of the Xorg graphical server.
  16147. @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
  16148. Path to xauth.
  16149. @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
  16150. Path to Xephyr.
  16151. @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
  16152. Script to run after starting xorg-server.
  16153. @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
  16154. Script to run before stopping xorg-server.
  16155. @item @code{xsession-command} (default: @code{xinitrc})
  16156. Script to run before starting a X session.
  16157. @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
  16158. Directory to look for desktop files starting X sessions.
  16159. @item @code{minimum-vt} (default: 7)
  16160. Minimum VT to use.
  16161. @item @code{auto-login-user} (default "")
  16162. User to use for auto-login.
  16163. @item @code{auto-login-session} (default "")
  16164. Desktop file to use for auto-login.
  16165. @item @code{relogin?} (default #f)
  16166. Relogin after logout.
  16167. @end table
  16168. @end deftp
  16169. @cindex login manager
  16170. @cindex X11 login
  16171. @defvr {Scheme Variable} sddm-service-type
  16172. This is the type of the service to run the
  16173. @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
  16174. must be a @code{sddm-configuration} record (see below).
  16175. Here's an example use:
  16176. @lisp
  16177. (service sddm-service-type
  16178. (sddm-configuration
  16179. (auto-login-user "alice")
  16180. (auto-login-session "xfce.desktop")))
  16181. @end lisp
  16182. @end defvr
  16183. @deftp {Data Type} sddm-configuration
  16184. This data type represents the configuration of the SDDM login manager.
  16185. The available fields are:
  16186. @table @asis
  16187. @item @code{sddm} (default: @code{sddm})
  16188. The SDDM package to use.
  16189. @item @code{display-server} (default: @code{"x11"})
  16190. This must be either @code{"x11"} or @code{"wayland"}.
  16191. @c FIXME: Add more fields.
  16192. @item @code{auto-login-user} (default: @code{""})
  16193. If non-empty, this is the user account under which to log in
  16194. automatically.
  16195. @item @code{auto-login-session} (default: @code{""})
  16196. If non-empty, this is the @file{.desktop} file name to use as the
  16197. auto-login session.
  16198. @end table
  16199. @end deftp
  16200. @cindex Xorg, configuration
  16201. @deftp {Data Type} xorg-configuration
  16202. This data type represents the configuration of the Xorg graphical display
  16203. server. Note that there is no Xorg service; instead, the X server is started
  16204. by a ``display manager'' such as GDM, SDDM, and SLiM@. Thus, the configuration
  16205. of these display managers aggregates an @code{xorg-configuration} record.
  16206. @table @asis
  16207. @item @code{modules} (default: @code{%default-xorg-modules})
  16208. This is a list of @dfn{module packages} loaded by the Xorg
  16209. server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
  16210. @item @code{fonts} (default: @code{%default-xorg-fonts})
  16211. This is a list of font directories to add to the server's @dfn{font path}.
  16212. @item @code{drivers} (default: @code{'()})
  16213. This must be either the empty list, in which case Xorg chooses a graphics
  16214. driver automatically, or a list of driver names that will be tried in this
  16215. order---e.g., @code{("modesetting" "vesa")}.
  16216. @item @code{resolutions} (default: @code{'()})
  16217. When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
  16218. resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
  16219. 768) (640 480))}.
  16220. @cindex keyboard layout, for Xorg
  16221. @cindex keymap, for Xorg
  16222. @item @code{keyboard-layout} (default: @code{#f})
  16223. If this is @code{#f}, Xorg uses the default keyboard layout---usually US
  16224. English (``qwerty'') for a 105-key PC keyboard.
  16225. Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
  16226. layout in use when Xorg is running. @xref{Keyboard Layout}, for more
  16227. information on how to specify the keyboard layout.
  16228. @item @code{extra-config} (default: @code{'()})
  16229. This is a list of strings or objects appended to the configuration file. It
  16230. is used to pass extra text to be added verbatim to the configuration file.
  16231. @item @code{server} (default: @code{xorg-server})
  16232. This is the package providing the Xorg server.
  16233. @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
  16234. This is the list of command-line arguments to pass to the X server. The
  16235. default is @code{-nolisten tcp}.
  16236. @end table
  16237. @end deftp
  16238. @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
  16239. [@var{login-manager-service-type}]
  16240. Tell the log-in manager (of type @var{login-manager-service-type}) to use
  16241. @var{config}, an @code{<xorg-configuration>} record.
  16242. Since the Xorg configuration is embedded in the log-in manager's
  16243. configuration---e.g., @code{gdm-configuration}---this procedure provides a
  16244. shorthand to set the Xorg configuration.
  16245. @end deffn
  16246. @deffn {Scheme Procedure} xorg-start-command [@var{config}]
  16247. Return a @code{startx} script in which the modules, fonts, etc. specified
  16248. in @var{config}, are available. The result should be used in place of
  16249. @code{startx}.
  16250. Usually the X server is started by a login manager.
  16251. @end deffn
  16252. @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
  16253. Add @var{package}, a package for a screen locker or screen saver whose
  16254. command is @var{program}, to the set of setuid programs and add a PAM entry
  16255. for it. For example:
  16256. @lisp
  16257. (screen-locker-service xlockmore "xlock")
  16258. @end lisp
  16259. makes the good ol' XlockMore usable.
  16260. @end deffn
  16261. @node Printing Services
  16262. @subsection Printing Services
  16263. @cindex printer support with CUPS
  16264. The @code{(gnu services cups)} module provides a Guix service definition
  16265. for the CUPS printing service. To add printer support to a Guix
  16266. system, add a @code{cups-service} to the operating system definition:
  16267. @deffn {Scheme Variable} cups-service-type
  16268. The service type for the CUPS print server. Its value should be a valid
  16269. CUPS configuration (see below). To use the default settings, simply
  16270. write:
  16271. @lisp
  16272. (service cups-service-type)
  16273. @end lisp
  16274. @end deffn
  16275. The CUPS configuration controls the basic things about your CUPS
  16276. installation: what interfaces it listens on, what to do if a print job
  16277. fails, how much logging to do, and so on. To actually add a printer,
  16278. you have to visit the @url{http://localhost:631} URL, or use a tool such
  16279. as GNOME's printer configuration services. By default, configuring a
  16280. CUPS service will generate a self-signed certificate if needed, for
  16281. secure connections to the print server.
  16282. Suppose you want to enable the Web interface of CUPS and also add
  16283. support for Epson printers @i{via} the @code{epson-inkjet-printer-escpr}
  16284. package and for HP printers @i{via} the @code{hplip-minimal} package.
  16285. You can do that directly, like this (you need to use the
  16286. @code{(gnu packages cups)} module):
  16287. @lisp
  16288. (service cups-service-type
  16289. (cups-configuration
  16290. (web-interface? #t)
  16291. (extensions
  16292. (list cups-filters epson-inkjet-printer-escpr hplip-minimal))))
  16293. @end lisp
  16294. Note: If you wish to use the Qt5 based GUI which comes with the hplip
  16295. package then it is suggested that you install the @code{hplip} package,
  16296. either in your OS configuration file or as your user.
  16297. The available configuration parameters follow. Each parameter
  16298. definition is preceded by its type; for example, @samp{string-list foo}
  16299. indicates that the @code{foo} parameter should be specified as a list of
  16300. strings. There is also a way to specify the configuration as a string,
  16301. if you have an old @code{cupsd.conf} file that you want to port over
  16302. from some other system; see the end for more details.
  16303. @c The following documentation was initially generated by
  16304. @c (generate-documentation) in (gnu services cups). Manually maintained
  16305. @c documentation is better, so we shouldn't hesitate to edit below as
  16306. @c needed. However if the change you want to make to this documentation
  16307. @c can be done in an automated way, it's probably easier to change
  16308. @c (generate-documentation) than to make it below and have to deal with
  16309. @c the churn as CUPS updates.
  16310. Available @code{cups-configuration} fields are:
  16311. @deftypevr {@code{cups-configuration} parameter} package cups
  16312. The CUPS package.
  16313. @end deftypevr
  16314. @deftypevr {@code{cups-configuration} parameter} package-list extensions (default: @code{(list brlaser cups-filters epson-inkjet-printer-escpr foomatic-filters hplip-minimal splix)})
  16315. Drivers and other extensions to the CUPS package.
  16316. @end deftypevr
  16317. @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
  16318. Configuration of where to write logs, what directories to use for print
  16319. spools, and related privileged configuration parameters.
  16320. Available @code{files-configuration} fields are:
  16321. @deftypevr {@code{files-configuration} parameter} log-location access-log
  16322. Defines the access log filename. Specifying a blank filename disables
  16323. access log generation. The value @code{stderr} causes log entries to be
  16324. sent to the standard error file when the scheduler is running in the
  16325. foreground, or to the system log daemon when run in the background. The
  16326. value @code{syslog} causes log entries to be sent to the system log
  16327. daemon. The server name may be included in filenames using the string
  16328. @code{%s}, as in @code{/var/log/cups/%s-access_log}.
  16329. Defaults to @samp{"/var/log/cups/access_log"}.
  16330. @end deftypevr
  16331. @deftypevr {@code{files-configuration} parameter} file-name cache-dir
  16332. Where CUPS should cache data.
  16333. Defaults to @samp{"/var/cache/cups"}.
  16334. @end deftypevr
  16335. @deftypevr {@code{files-configuration} parameter} string config-file-perm
  16336. Specifies the permissions for all configuration files that the scheduler
  16337. writes.
  16338. Note that the permissions for the printers.conf file are currently
  16339. masked to only allow access from the scheduler user (typically root).
  16340. This is done because printer device URIs sometimes contain sensitive
  16341. authentication information that should not be generally known on the
  16342. system. There is no way to disable this security feature.
  16343. Defaults to @samp{"0640"}.
  16344. @end deftypevr
  16345. @deftypevr {@code{files-configuration} parameter} log-location error-log
  16346. Defines the error log filename. Specifying a blank filename disables
  16347. error log generation. The value @code{stderr} causes log entries to be
  16348. sent to the standard error file when the scheduler is running in the
  16349. foreground, or to the system log daemon when run in the background. The
  16350. value @code{syslog} causes log entries to be sent to the system log
  16351. daemon. The server name may be included in filenames using the string
  16352. @code{%s}, as in @code{/var/log/cups/%s-error_log}.
  16353. Defaults to @samp{"/var/log/cups/error_log"}.
  16354. @end deftypevr
  16355. @deftypevr {@code{files-configuration} parameter} string fatal-errors
  16356. Specifies which errors are fatal, causing the scheduler to exit. The
  16357. kind strings are:
  16358. @table @code
  16359. @item none
  16360. No errors are fatal.
  16361. @item all
  16362. All of the errors below are fatal.
  16363. @item browse
  16364. Browsing initialization errors are fatal, for example failed connections
  16365. to the DNS-SD daemon.
  16366. @item config
  16367. Configuration file syntax errors are fatal.
  16368. @item listen
  16369. Listen or Port errors are fatal, except for IPv6 failures on the
  16370. loopback or @code{any} addresses.
  16371. @item log
  16372. Log file creation or write errors are fatal.
  16373. @item permissions
  16374. Bad startup file permissions are fatal, for example shared TLS
  16375. certificate and key files with world-read permissions.
  16376. @end table
  16377. Defaults to @samp{"all -browse"}.
  16378. @end deftypevr
  16379. @deftypevr {@code{files-configuration} parameter} boolean file-device?
  16380. Specifies whether the file pseudo-device can be used for new printer
  16381. queues. The URI @uref{file:///dev/null} is always allowed.
  16382. Defaults to @samp{#f}.
  16383. @end deftypevr
  16384. @deftypevr {@code{files-configuration} parameter} string group
  16385. Specifies the group name or ID that will be used when executing external
  16386. programs.
  16387. Defaults to @samp{"lp"}.
  16388. @end deftypevr
  16389. @deftypevr {@code{files-configuration} parameter} string log-file-group
  16390. Specifies the group name or ID that will be used for log files.
  16391. Defaults to @samp{"lpadmin"}.
  16392. @end deftypevr
  16393. @deftypevr {@code{files-configuration} parameter} string log-file-perm
  16394. Specifies the permissions for all log files that the scheduler writes.
  16395. Defaults to @samp{"0644"}.
  16396. @end deftypevr
  16397. @deftypevr {@code{files-configuration} parameter} log-location page-log
  16398. Defines the page log filename. Specifying a blank filename disables
  16399. page log generation. The value @code{stderr} causes log entries to be
  16400. sent to the standard error file when the scheduler is running in the
  16401. foreground, or to the system log daemon when run in the background. The
  16402. value @code{syslog} causes log entries to be sent to the system log
  16403. daemon. The server name may be included in filenames using the string
  16404. @code{%s}, as in @code{/var/log/cups/%s-page_log}.
  16405. Defaults to @samp{"/var/log/cups/page_log"}.
  16406. @end deftypevr
  16407. @deftypevr {@code{files-configuration} parameter} string remote-root
  16408. Specifies the username that is associated with unauthenticated accesses
  16409. by clients claiming to be the root user. The default is @code{remroot}.
  16410. Defaults to @samp{"remroot"}.
  16411. @end deftypevr
  16412. @deftypevr {@code{files-configuration} parameter} file-name request-root
  16413. Specifies the directory that contains print jobs and other HTTP request
  16414. data.
  16415. Defaults to @samp{"/var/spool/cups"}.
  16416. @end deftypevr
  16417. @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
  16418. Specifies the level of security sandboxing that is applied to print
  16419. filters, backends, and other child processes of the scheduler; either
  16420. @code{relaxed} or @code{strict}. This directive is currently only
  16421. used/supported on macOS.
  16422. Defaults to @samp{strict}.
  16423. @end deftypevr
  16424. @deftypevr {@code{files-configuration} parameter} file-name server-keychain
  16425. Specifies the location of TLS certificates and private keys. CUPS will
  16426. look for public and private keys in this directory: @file{.crt} files
  16427. for PEM-encoded certificates and corresponding @file{.key} files for
  16428. PEM-encoded private keys.
  16429. Defaults to @samp{"/etc/cups/ssl"}.
  16430. @end deftypevr
  16431. @deftypevr {@code{files-configuration} parameter} file-name server-root
  16432. Specifies the directory containing the server configuration files.
  16433. Defaults to @samp{"/etc/cups"}.
  16434. @end deftypevr
  16435. @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
  16436. Specifies whether the scheduler calls fsync(2) after writing
  16437. configuration or state files.
  16438. Defaults to @samp{#f}.
  16439. @end deftypevr
  16440. @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
  16441. Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
  16442. @end deftypevr
  16443. @deftypevr {@code{files-configuration} parameter} file-name temp-dir
  16444. Specifies the directory where temporary files are stored.
  16445. Defaults to @samp{"/var/spool/cups/tmp"}.
  16446. @end deftypevr
  16447. @deftypevr {@code{files-configuration} parameter} string user
  16448. Specifies the user name or ID that is used when running external
  16449. programs.
  16450. Defaults to @samp{"lp"}.
  16451. @end deftypevr
  16452. @deftypevr {@code{files-configuration} parameter} string set-env
  16453. Set the specified environment variable to be passed to child processes.
  16454. Defaults to @samp{"variable value"}.
  16455. @end deftypevr
  16456. @end deftypevr
  16457. @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
  16458. Specifies the logging level for the AccessLog file. The @code{config}
  16459. level logs when printers and classes are added, deleted, or modified and
  16460. when configuration files are accessed or updated. The @code{actions}
  16461. level logs when print jobs are submitted, held, released, modified, or
  16462. canceled, and any of the conditions for @code{config}. The @code{all}
  16463. level logs all requests.
  16464. Defaults to @samp{actions}.
  16465. @end deftypevr
  16466. @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
  16467. Specifies whether to purge job history data automatically when it is no
  16468. longer required for quotas.
  16469. Defaults to @samp{#f}.
  16470. @end deftypevr
  16471. @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
  16472. Specifies a list of DNS-SD sub-types to advertise for each shared printer.
  16473. For example, @samp{"_cups" "_print"} will tell network clients that both
  16474. CUPS sharing and IPP Everywhere are supported.
  16475. Defaults to @samp{"_cups"}.
  16476. @end deftypevr
  16477. @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
  16478. Specifies which protocols to use for local printer sharing.
  16479. Defaults to @samp{dnssd}.
  16480. @end deftypevr
  16481. @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
  16482. Specifies whether the CUPS web interface is advertised.
  16483. Defaults to @samp{#f}.
  16484. @end deftypevr
  16485. @deftypevr {@code{cups-configuration} parameter} boolean browsing?
  16486. Specifies whether shared printers are advertised.
  16487. Defaults to @samp{#f}.
  16488. @end deftypevr
  16489. @deftypevr {@code{cups-configuration} parameter} string classification
  16490. Specifies the security classification of the server. Any valid banner
  16491. name can be used, including @samp{"classified"}, @samp{"confidential"},
  16492. @samp{"secret"}, @samp{"topsecret"}, and @samp{"unclassified"}, or the
  16493. banner can be omitted to disable secure printing functions.
  16494. Defaults to @samp{""}.
  16495. @end deftypevr
  16496. @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
  16497. Specifies whether users may override the classification (cover page) of
  16498. individual print jobs using the @code{job-sheets} option.
  16499. Defaults to @samp{#f}.
  16500. @end deftypevr
  16501. @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
  16502. Specifies the default type of authentication to use.
  16503. Defaults to @samp{Basic}.
  16504. @end deftypevr
  16505. @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
  16506. Specifies whether encryption will be used for authenticated requests.
  16507. Defaults to @samp{Required}.
  16508. @end deftypevr
  16509. @deftypevr {@code{cups-configuration} parameter} string default-language
  16510. Specifies the default language to use for text and web content.
  16511. Defaults to @samp{"en"}.
  16512. @end deftypevr
  16513. @deftypevr {@code{cups-configuration} parameter} string default-paper-size
  16514. Specifies the default paper size for new print queues. @samp{"Auto"}
  16515. uses a locale-specific default, while @samp{"None"} specifies there is
  16516. no default paper size. Specific size names are typically
  16517. @samp{"Letter"} or @samp{"A4"}.
  16518. Defaults to @samp{"Auto"}.
  16519. @end deftypevr
  16520. @deftypevr {@code{cups-configuration} parameter} string default-policy
  16521. Specifies the default access policy to use.
  16522. Defaults to @samp{"default"}.
  16523. @end deftypevr
  16524. @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
  16525. Specifies whether local printers are shared by default.
  16526. Defaults to @samp{#t}.
  16527. @end deftypevr
  16528. @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
  16529. Specifies the delay for updating of configuration and state files, in
  16530. seconds. A value of 0 causes the update to happen as soon as possible,
  16531. typically within a few milliseconds.
  16532. Defaults to @samp{30}.
  16533. @end deftypevr
  16534. @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
  16535. Specifies what to do when an error occurs. Possible values are
  16536. @code{abort-job}, which will discard the failed print job;
  16537. @code{retry-job}, which will retry the job at a later time;
  16538. @code{retry-current-job}, which retries the failed job immediately; and
  16539. @code{stop-printer}, which stops the printer.
  16540. Defaults to @samp{stop-printer}.
  16541. @end deftypevr
  16542. @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
  16543. Specifies the maximum cost of filters that are run concurrently, which
  16544. can be used to minimize disk, memory, and CPU resource problems. A
  16545. limit of 0 disables filter limiting. An average print to a
  16546. non-PostScript printer needs a filter limit of about 200. A PostScript
  16547. printer needs about half that (100). Setting the limit below these
  16548. thresholds will effectively limit the scheduler to printing a single job
  16549. at any time.
  16550. Defaults to @samp{0}.
  16551. @end deftypevr
  16552. @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
  16553. Specifies the scheduling priority of filters that are run to print a
  16554. job. The nice value ranges from 0, the highest priority, to 19, the
  16555. lowest priority.
  16556. Defaults to @samp{0}.
  16557. @end deftypevr
  16558. @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
  16559. Specifies whether to do reverse lookups on connecting clients. The
  16560. @code{double} setting causes @code{cupsd} to verify that the hostname
  16561. resolved from the address matches one of the addresses returned for that
  16562. hostname. Double lookups also prevent clients with unregistered
  16563. addresses from connecting to your server. Only set this option to
  16564. @code{#t} or @code{double} if absolutely required.
  16565. Defaults to @samp{#f}.
  16566. @end deftypevr
  16567. @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
  16568. Specifies the number of seconds to wait before killing the filters and
  16569. backend associated with a canceled or held job.
  16570. Defaults to @samp{30}.
  16571. @end deftypevr
  16572. @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
  16573. Specifies the interval between retries of jobs in seconds. This is
  16574. typically used for fax queues but can also be used with normal print
  16575. queues whose error policy is @code{retry-job} or
  16576. @code{retry-current-job}.
  16577. Defaults to @samp{30}.
  16578. @end deftypevr
  16579. @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
  16580. Specifies the number of retries that are done for jobs. This is
  16581. typically used for fax queues but can also be used with normal print
  16582. queues whose error policy is @code{retry-job} or
  16583. @code{retry-current-job}.
  16584. Defaults to @samp{5}.
  16585. @end deftypevr
  16586. @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
  16587. Specifies whether to support HTTP keep-alive connections.
  16588. Defaults to @samp{#t}.
  16589. @end deftypevr
  16590. @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
  16591. Specifies the maximum size of print files, IPP requests, and HTML form
  16592. data. A limit of 0 disables the limit check.
  16593. Defaults to @samp{0}.
  16594. @end deftypevr
  16595. @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
  16596. Listens on the specified interfaces for connections. Valid values are
  16597. of the form @var{address}:@var{port}, where @var{address} is either an
  16598. IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
  16599. indicate all addresses. Values can also be file names of local UNIX
  16600. domain sockets. The Listen directive is similar to the Port directive
  16601. but allows you to restrict access to specific interfaces or networks.
  16602. @end deftypevr
  16603. @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
  16604. Specifies the number of pending connections that will be allowed. This
  16605. normally only affects very busy servers that have reached the MaxClients
  16606. limit, but can also be triggered by large numbers of simultaneous
  16607. connections. When the limit is reached, the operating system will
  16608. refuse additional connections until the scheduler can accept the pending
  16609. ones.
  16610. Defaults to @samp{128}.
  16611. @end deftypevr
  16612. @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
  16613. Specifies a set of additional access controls.
  16614. Available @code{location-access-controls} fields are:
  16615. @deftypevr {@code{location-access-controls} parameter} file-name path
  16616. Specifies the URI path to which the access control applies.
  16617. @end deftypevr
  16618. @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
  16619. Access controls for all access to this path, in the same format as the
  16620. @code{access-controls} of @code{operation-access-control}.
  16621. Defaults to @samp{()}.
  16622. @end deftypevr
  16623. @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
  16624. Access controls for method-specific access to this path.
  16625. Defaults to @samp{()}.
  16626. Available @code{method-access-controls} fields are:
  16627. @deftypevr {@code{method-access-controls} parameter} boolean reverse?
  16628. If @code{#t}, apply access controls to all methods except the listed
  16629. methods. Otherwise apply to only the listed methods.
  16630. Defaults to @samp{#f}.
  16631. @end deftypevr
  16632. @deftypevr {@code{method-access-controls} parameter} method-list methods
  16633. Methods to which this access control applies.
  16634. Defaults to @samp{()}.
  16635. @end deftypevr
  16636. @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
  16637. Access control directives, as a list of strings. Each string should be
  16638. one directive, such as @samp{"Order allow,deny"}.
  16639. Defaults to @samp{()}.
  16640. @end deftypevr
  16641. @end deftypevr
  16642. @end deftypevr
  16643. @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
  16644. Specifies the number of debugging messages that are retained for logging
  16645. if an error occurs in a print job. Debug messages are logged regardless
  16646. of the LogLevel setting.
  16647. Defaults to @samp{100}.
  16648. @end deftypevr
  16649. @deftypevr {@code{cups-configuration} parameter} log-level log-level
  16650. Specifies the level of logging for the ErrorLog file. The value
  16651. @code{none} stops all logging while @code{debug2} logs everything.
  16652. Defaults to @samp{info}.
  16653. @end deftypevr
  16654. @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
  16655. Specifies the format of the date and time in the log files. The value
  16656. @code{standard} logs whole seconds while @code{usecs} logs microseconds.
  16657. Defaults to @samp{standard}.
  16658. @end deftypevr
  16659. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
  16660. Specifies the maximum number of simultaneous clients that are allowed by
  16661. the scheduler.
  16662. Defaults to @samp{100}.
  16663. @end deftypevr
  16664. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
  16665. Specifies the maximum number of simultaneous clients that are allowed
  16666. from a single address.
  16667. Defaults to @samp{100}.
  16668. @end deftypevr
  16669. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
  16670. Specifies the maximum number of copies that a user can print of each
  16671. job.
  16672. Defaults to @samp{9999}.
  16673. @end deftypevr
  16674. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
  16675. Specifies the maximum time a job may remain in the @code{indefinite}
  16676. hold state before it is canceled. A value of 0 disables cancellation of
  16677. held jobs.
  16678. Defaults to @samp{0}.
  16679. @end deftypevr
  16680. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
  16681. Specifies the maximum number of simultaneous jobs that are allowed. Set
  16682. to 0 to allow an unlimited number of jobs.
  16683. Defaults to @samp{500}.
  16684. @end deftypevr
  16685. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
  16686. Specifies the maximum number of simultaneous jobs that are allowed per
  16687. printer. A value of 0 allows up to MaxJobs jobs per printer.
  16688. Defaults to @samp{0}.
  16689. @end deftypevr
  16690. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
  16691. Specifies the maximum number of simultaneous jobs that are allowed per
  16692. user. A value of 0 allows up to MaxJobs jobs per user.
  16693. Defaults to @samp{0}.
  16694. @end deftypevr
  16695. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
  16696. Specifies the maximum time a job may take to print before it is
  16697. canceled, in seconds. Set to 0 to disable cancellation of ``stuck'' jobs.
  16698. Defaults to @samp{10800}.
  16699. @end deftypevr
  16700. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
  16701. Specifies the maximum size of the log files before they are rotated, in
  16702. bytes. The value 0 disables log rotation.
  16703. Defaults to @samp{1048576}.
  16704. @end deftypevr
  16705. @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
  16706. Specifies the maximum amount of time to allow between files in a
  16707. multiple file print job, in seconds.
  16708. Defaults to @samp{900}.
  16709. @end deftypevr
  16710. @deftypevr {@code{cups-configuration} parameter} string page-log-format
  16711. Specifies the format of PageLog lines. Sequences beginning with percent
  16712. (@samp{%}) characters are replaced with the corresponding information,
  16713. while all other characters are copied literally. The following percent
  16714. sequences are recognized:
  16715. @table @samp
  16716. @item %%
  16717. insert a single percent character
  16718. @item %@{name@}
  16719. insert the value of the specified IPP attribute
  16720. @item %C
  16721. insert the number of copies for the current page
  16722. @item %P
  16723. insert the current page number
  16724. @item %T
  16725. insert the current date and time in common log format
  16726. @item %j
  16727. insert the job ID
  16728. @item %p
  16729. insert the printer name
  16730. @item %u
  16731. insert the username
  16732. @end table
  16733. A value of the empty string disables page logging. The string @code{%p
  16734. %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
  16735. %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
  16736. standard items.
  16737. Defaults to @samp{""}.
  16738. @end deftypevr
  16739. @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
  16740. Passes the specified environment variable(s) to child processes; a list
  16741. of strings.
  16742. Defaults to @samp{()}.
  16743. @end deftypevr
  16744. @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
  16745. Specifies named access control policies.
  16746. Available @code{policy-configuration} fields are:
  16747. @deftypevr {@code{policy-configuration} parameter} string name
  16748. Name of the policy.
  16749. @end deftypevr
  16750. @deftypevr {@code{policy-configuration} parameter} string job-private-access
  16751. Specifies an access list for a job's private values. @code{@@ACL} maps
  16752. to the printer's requesting-user-name-allowed or
  16753. requesting-user-name-denied values. @code{@@OWNER} maps to the job's
  16754. owner. @code{@@SYSTEM} maps to the groups listed for the
  16755. @code{system-group} field of the @code{files-configuration},
  16756. which is reified into the @code{cups-files.conf(5)} file. Other
  16757. possible elements of the access list include specific user names, and
  16758. @code{@@@var{group}} to indicate members of a specific group. The
  16759. access list may also be simply @code{all} or @code{default}.
  16760. Defaults to @samp{"@@OWNER @@SYSTEM"}.
  16761. @end deftypevr
  16762. @deftypevr {@code{policy-configuration} parameter} string job-private-values
  16763. Specifies the list of job values to make private, or @code{all},
  16764. @code{default}, or @code{none}.
  16765. Defaults to @samp{"job-name job-originating-host-name
  16766. job-originating-user-name phone"}.
  16767. @end deftypevr
  16768. @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
  16769. Specifies an access list for a subscription's private values.
  16770. @code{@@ACL} maps to the printer's requesting-user-name-allowed or
  16771. requesting-user-name-denied values. @code{@@OWNER} maps to the job's
  16772. owner. @code{@@SYSTEM} maps to the groups listed for the
  16773. @code{system-group} field of the @code{files-configuration},
  16774. which is reified into the @code{cups-files.conf(5)} file. Other
  16775. possible elements of the access list include specific user names, and
  16776. @code{@@@var{group}} to indicate members of a specific group. The
  16777. access list may also be simply @code{all} or @code{default}.
  16778. Defaults to @samp{"@@OWNER @@SYSTEM"}.
  16779. @end deftypevr
  16780. @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
  16781. Specifies the list of job values to make private, or @code{all},
  16782. @code{default}, or @code{none}.
  16783. Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
  16784. notify-subscriber-user-name notify-user-data"}.
  16785. @end deftypevr
  16786. @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
  16787. Access control by IPP operation.
  16788. Defaults to @samp{()}.
  16789. @end deftypevr
  16790. @end deftypevr
  16791. @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
  16792. Specifies whether job files (documents) are preserved after a job is
  16793. printed. If a numeric value is specified, job files are preserved for
  16794. the indicated number of seconds after printing. Otherwise a boolean
  16795. value applies indefinitely.
  16796. Defaults to @samp{86400}.
  16797. @end deftypevr
  16798. @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
  16799. Specifies whether the job history is preserved after a job is printed.
  16800. If a numeric value is specified, the job history is preserved for the
  16801. indicated number of seconds after printing. If @code{#t}, the job
  16802. history is preserved until the MaxJobs limit is reached.
  16803. Defaults to @samp{#t}.
  16804. @end deftypevr
  16805. @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
  16806. Specifies the amount of time to wait for job completion before
  16807. restarting the scheduler.
  16808. Defaults to @samp{30}.
  16809. @end deftypevr
  16810. @deftypevr {@code{cups-configuration} parameter} string rip-cache
  16811. Specifies the maximum amount of memory to use when converting documents
  16812. into bitmaps for a printer.
  16813. Defaults to @samp{"128m"}.
  16814. @end deftypevr
  16815. @deftypevr {@code{cups-configuration} parameter} string server-admin
  16816. Specifies the email address of the server administrator.
  16817. Defaults to @samp{"root@@localhost.localdomain"}.
  16818. @end deftypevr
  16819. @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
  16820. The ServerAlias directive is used for HTTP Host header validation when
  16821. clients connect to the scheduler from external interfaces. Using the
  16822. special name @code{*} can expose your system to known browser-based DNS
  16823. rebinding attacks, even when accessing sites through a firewall. If the
  16824. auto-discovery of alternate names does not work, we recommend listing
  16825. each alternate name with a ServerAlias directive instead of using
  16826. @code{*}.
  16827. Defaults to @samp{*}.
  16828. @end deftypevr
  16829. @deftypevr {@code{cups-configuration} parameter} string server-name
  16830. Specifies the fully-qualified host name of the server.
  16831. Defaults to @samp{"localhost"}.
  16832. @end deftypevr
  16833. @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
  16834. Specifies what information is included in the Server header of HTTP
  16835. responses. @code{None} disables the Server header. @code{ProductOnly}
  16836. reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
  16837. reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
  16838. @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
  16839. the output of the @code{uname} command. @code{Full} reports @code{CUPS
  16840. 2.0.0 (@var{uname}) IPP/2.0}.
  16841. Defaults to @samp{Minimal}.
  16842. @end deftypevr
  16843. @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
  16844. Listens on the specified interfaces for encrypted connections. Valid
  16845. values are of the form @var{address}:@var{port}, where @var{address} is
  16846. either an IPv6 address enclosed in brackets, an IPv4 address, or
  16847. @code{*} to indicate all addresses.
  16848. Defaults to @samp{()}.
  16849. @end deftypevr
  16850. @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
  16851. Sets encryption options. By default, CUPS only supports encryption
  16852. using TLS v1.0 or higher using known secure cipher suites. Security is
  16853. reduced when @code{Allow} options are used, and enhanced when @code{Deny}
  16854. options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
  16855. suites, which are required for some older clients. The @code{AllowSSL3} option
  16856. enables SSL v3.0, which is required for some older clients that do not support
  16857. TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
  16858. @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
  16859. protocol version to TLS v1.1.
  16860. Defaults to @samp{()}.
  16861. @end deftypevr
  16862. @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
  16863. Specifies whether the scheduler requires clients to strictly adhere to
  16864. the IPP specifications.
  16865. Defaults to @samp{#f}.
  16866. @end deftypevr
  16867. @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
  16868. Specifies the HTTP request timeout, in seconds.
  16869. Defaults to @samp{900}.
  16870. @end deftypevr
  16871. @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
  16872. Specifies whether the web interface is enabled.
  16873. Defaults to @samp{#f}.
  16874. @end deftypevr
  16875. At this point you're probably thinking ``oh dear, Guix manual, I like
  16876. you but you can stop already with the configuration options''. Indeed.
  16877. However, one more point: it could be that you have an existing
  16878. @code{cupsd.conf} that you want to use. In that case, you can pass an
  16879. @code{opaque-cups-configuration} as the configuration of a
  16880. @code{cups-service-type}.
  16881. Available @code{opaque-cups-configuration} fields are:
  16882. @deftypevr {@code{opaque-cups-configuration} parameter} package cups
  16883. The CUPS package.
  16884. @end deftypevr
  16885. @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
  16886. The contents of the @code{cupsd.conf}, as a string.
  16887. @end deftypevr
  16888. @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
  16889. The contents of the @code{cups-files.conf} file, as a string.
  16890. @end deftypevr
  16891. For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
  16892. strings of the same name, you could instantiate a CUPS service like
  16893. this:
  16894. @lisp
  16895. (service cups-service-type
  16896. (opaque-cups-configuration
  16897. (cupsd.conf cupsd.conf)
  16898. (cups-files.conf cups-files.conf)))
  16899. @end lisp
  16900. @node Desktop Services
  16901. @subsection Desktop Services
  16902. The @code{(gnu services desktop)} module provides services that are
  16903. usually useful in the context of a ``desktop'' setup---that is, on a
  16904. machine running a graphical display server, possibly with graphical user
  16905. interfaces, etc. It also defines services that provide specific desktop
  16906. environments like GNOME, Xfce or MATE.
  16907. To simplify things, the module defines a variable containing the set of
  16908. services that users typically expect on a machine with a graphical
  16909. environment and networking:
  16910. @defvr {Scheme Variable} %desktop-services
  16911. This is a list of services that builds upon @code{%base-services} and
  16912. adds or adjusts services for a typical ``desktop'' setup.
  16913. In particular, it adds a graphical login manager (@pxref{X Window,
  16914. @code{gdm-service-type}}), screen lockers, a network management tool
  16915. (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
  16916. support (@pxref{Networking Services, @code{modem-manager-service-type}}),
  16917. energy and color management services, the @code{elogind} login and seat
  16918. manager, the Polkit privilege service, the GeoClue location service, the
  16919. AccountsService daemon that allows authorized users change system passwords,
  16920. an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
  16921. name service switch service configured to be able to use @code{nss-mdns}
  16922. (@pxref{Name Service Switch, mDNS}).
  16923. @end defvr
  16924. The @code{%desktop-services} variable can be used as the @code{services}
  16925. field of an @code{operating-system} declaration (@pxref{operating-system
  16926. Reference, @code{services}}).
  16927. Additionally, the @code{gnome-desktop-service-type},
  16928. @code{xfce-desktop-service}, @code{mate-desktop-service-type},
  16929. @code{lxqt-desktop-service-type} and @code{enlightenment-desktop-service-type}
  16930. procedures can add GNOME, Xfce, MATE and/or Enlightenment to a system. To
  16931. ``add GNOME'' means that system-level services like the backlight adjustment
  16932. helpers and the power management utilities are added to the system, extending
  16933. @code{polkit} and @code{dbus} appropriately, allowing GNOME to operate with
  16934. elevated privileges on a limited number of special-purpose system interfaces.
  16935. Additionally, adding a service made by @code{gnome-desktop-service-type} adds
  16936. the GNOME metapackage to the system profile. Likewise, adding the Xfce
  16937. service not only adds the @code{xfce} metapackage to the system profile, but
  16938. it also gives the Thunar file manager the ability to open a ``root-mode'' file
  16939. management window, if the user authenticates using the administrator's
  16940. password via the standard polkit graphical interface. To ``add MATE'' means
  16941. that @code{polkit} and @code{dbus} are extended appropriately, allowing MATE
  16942. to operate with elevated privileges on a limited number of special-purpose
  16943. system interfaces. Additionally, adding a service of type
  16944. @code{mate-desktop-service-type} adds the MATE metapackage to the system
  16945. profile. ``Adding Enlightenment'' means that @code{dbus} is extended
  16946. appropriately, and several of Enlightenment's binaries are set as setuid,
  16947. allowing Enlightenment's screen locker and other functionality to work as
  16948. expected.
  16949. The desktop environments in Guix use the Xorg display server by
  16950. default. If you'd like to use the newer display server protocol
  16951. called Wayland, you need to enable Wayland support in GDM
  16952. (@pxref{wayland-gdm}). Another solution is to use the
  16953. @code{sddm-service} instead of GDM as the graphical login manager.
  16954. You should then select the ``GNOME (Wayland)'' session in SDDM@.
  16955. Alternatively you can also try starting GNOME on Wayland manually from a
  16956. TTY with the command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
  16957. gnome-session``. Currently only GNOME has support for Wayland.
  16958. @defvr {Scheme Variable} gnome-desktop-service-type
  16959. This is the type of the service that adds the @uref{https://www.gnome.org,
  16960. GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
  16961. object (see below).
  16962. This service adds the @code{gnome} package to the system profile, and extends
  16963. polkit with the actions from @code{gnome-settings-daemon}.
  16964. @end defvr
  16965. @deftp {Data Type} gnome-desktop-configuration
  16966. Configuration record for the GNOME desktop environment.
  16967. @table @asis
  16968. @item @code{gnome} (default: @code{gnome})
  16969. The GNOME package to use.
  16970. @end table
  16971. @end deftp
  16972. @defvr {Scheme Variable} xfce-desktop-service-type
  16973. This is the type of a service to run the @uref{Xfce, https://xfce.org/}
  16974. desktop environment. Its value is an @code{xfce-desktop-configuration} object
  16975. (see below).
  16976. This service adds the @code{xfce} package to the system profile, and
  16977. extends polkit with the ability for @code{thunar} to manipulate the file
  16978. system as root from within a user session, after the user has authenticated
  16979. with the administrator's password.
  16980. Note that @code{xfce4-panel} and its plugin packages should be installed in
  16981. the same profile to ensure compatibility. When using this service, you should
  16982. add extra plugins (@code{xfce4-whiskermenu-plugin},
  16983. @code{xfce4-weather-plugin}, etc.) to the @code{packages} field of your
  16984. @code{operating-system}.
  16985. @end defvr
  16986. @deftp {Data Type} xfce-desktop-configuration
  16987. Configuration record for the Xfce desktop environment.
  16988. @table @asis
  16989. @item @code{xfce} (default: @code{xfce})
  16990. The Xfce package to use.
  16991. @end table
  16992. @end deftp
  16993. @deffn {Scheme Variable} mate-desktop-service-type
  16994. This is the type of the service that runs the @uref{https://mate-desktop.org/,
  16995. MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
  16996. object (see below).
  16997. This service adds the @code{mate} package to the system
  16998. profile, and extends polkit with the actions from
  16999. @code{mate-settings-daemon}.
  17000. @end deffn
  17001. @deftp {Data Type} mate-desktop-configuration
  17002. Configuration record for the MATE desktop environment.
  17003. @table @asis
  17004. @item @code{mate} (default: @code{mate})
  17005. The MATE package to use.
  17006. @end table
  17007. @end deftp
  17008. @deffn {Scheme Variable} lxqt-desktop-service-type
  17009. This is the type of the service that runs the @uref{https://lxqt-project.org,
  17010. LXQt desktop environment}. Its value is a @code{lxqt-desktop-configuration}
  17011. object (see below).
  17012. This service adds the @code{lxqt} package to the system
  17013. profile.
  17014. @end deffn
  17015. @deftp {Data Type} lxqt-desktop-configuration
  17016. Configuration record for the LXQt desktop environment.
  17017. @table @asis
  17018. @item @code{lxqt} (default: @code{lxqt})
  17019. The LXQT package to use.
  17020. @end table
  17021. @end deftp
  17022. @deffn {Scheme Variable} enlightenment-desktop-service-type
  17023. Return a service that adds the @code{enlightenment} package to the system
  17024. profile, and extends dbus with actions from @code{efl}.
  17025. @end deffn
  17026. @deftp {Data Type} enlightenment-desktop-service-configuration
  17027. @table @asis
  17028. @item @code{enlightenment} (default: @code{enlightenment})
  17029. The enlightenment package to use.
  17030. @end table
  17031. @end deftp
  17032. Because the GNOME, Xfce and MATE desktop services pull in so many packages,
  17033. the default @code{%desktop-services} variable doesn't include any of
  17034. them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
  17035. @code{%desktop-services} in the @code{services} field of your
  17036. @code{operating-system}:
  17037. @lisp
  17038. (use-modules (gnu))
  17039. (use-service-modules desktop)
  17040. (operating-system
  17041. ...
  17042. ;; cons* adds items to the list given as its last argument.
  17043. (services (cons* (service gnome-desktop-service-type)
  17044. (service xfce-desktop-service)
  17045. %desktop-services))
  17046. ...)
  17047. @end lisp
  17048. These desktop environments will then be available as options in the
  17049. graphical login window.
  17050. The actual service definitions included in @code{%desktop-services} and
  17051. provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
  17052. are described below.
  17053. @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
  17054. Return a service that runs the ``system bus'', using @var{dbus}, with
  17055. support for @var{services}.
  17056. @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
  17057. facility. Its system bus is used to allow system services to communicate
  17058. and to be notified of system-wide events.
  17059. @var{services} must be a list of packages that provide an
  17060. @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
  17061. and policy files. For example, to allow avahi-daemon to use the system bus,
  17062. @var{services} must be equal to @code{(list avahi)}.
  17063. @end deffn
  17064. @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
  17065. Return a service that runs the @code{elogind} login and
  17066. seat management daemon. @uref{https://github.com/elogind/elogind,
  17067. Elogind} exposes a D-Bus interface that can be used to know which users
  17068. are logged in, know what kind of sessions they have open, suspend the
  17069. system, inhibit system suspend, reboot the system, and other tasks.
  17070. Elogind handles most system-level power events for a computer, for
  17071. example suspending the system when a lid is closed, or shutting it down
  17072. when the power button is pressed.
  17073. The @var{config} keyword argument specifies the configuration for
  17074. elogind, and should be the result of an @code{(elogind-configuration
  17075. (@var{parameter} @var{value})...)} invocation. Available parameters and
  17076. their default values are:
  17077. @table @code
  17078. @item kill-user-processes?
  17079. @code{#f}
  17080. @item kill-only-users
  17081. @code{()}
  17082. @item kill-exclude-users
  17083. @code{("root")}
  17084. @item inhibit-delay-max-seconds
  17085. @code{5}
  17086. @item handle-power-key
  17087. @code{poweroff}
  17088. @item handle-suspend-key
  17089. @code{suspend}
  17090. @item handle-hibernate-key
  17091. @code{hibernate}
  17092. @item handle-lid-switch
  17093. @code{suspend}
  17094. @item handle-lid-switch-docked
  17095. @code{ignore}
  17096. @item handle-lid-switch-external-power
  17097. @code{ignore}
  17098. @item power-key-ignore-inhibited?
  17099. @code{#f}
  17100. @item suspend-key-ignore-inhibited?
  17101. @code{#f}
  17102. @item hibernate-key-ignore-inhibited?
  17103. @code{#f}
  17104. @item lid-switch-ignore-inhibited?
  17105. @code{#t}
  17106. @item holdoff-timeout-seconds
  17107. @code{30}
  17108. @item idle-action
  17109. @code{ignore}
  17110. @item idle-action-seconds
  17111. @code{(* 30 60)}
  17112. @item runtime-directory-size-percent
  17113. @code{10}
  17114. @item runtime-directory-size
  17115. @code{#f}
  17116. @item remove-ipc?
  17117. @code{#t}
  17118. @item suspend-state
  17119. @code{("mem" "standby" "freeze")}
  17120. @item suspend-mode
  17121. @code{()}
  17122. @item hibernate-state
  17123. @code{("disk")}
  17124. @item hibernate-mode
  17125. @code{("platform" "shutdown")}
  17126. @item hybrid-sleep-state
  17127. @code{("disk")}
  17128. @item hybrid-sleep-mode
  17129. @code{("suspend" "platform" "shutdown")}
  17130. @end table
  17131. @end deffn
  17132. @deffn {Scheme Procedure} accountsservice-service @
  17133. [#:accountsservice @var{accountsservice}]
  17134. Return a service that runs AccountsService, a system service that can
  17135. list available accounts, change their passwords, and so on.
  17136. AccountsService integrates with PolicyKit to enable unprivileged users
  17137. to acquire the capability to modify their system configuration.
  17138. @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
  17139. accountsservice web site} for more information.
  17140. The @var{accountsservice} keyword argument is the @code{accountsservice}
  17141. package to expose as a service.
  17142. @end deffn
  17143. @deffn {Scheme Procedure} polkit-service @
  17144. [#:polkit @var{polkit}]
  17145. Return a service that runs the
  17146. @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
  17147. management service}, which allows system administrators to grant access to
  17148. privileged operations in a structured way. By querying the Polkit service, a
  17149. privileged system component can know when it should grant additional
  17150. capabilities to ordinary users. For example, an ordinary user can be granted
  17151. the capability to suspend the system if the user is logged in locally.
  17152. @end deffn
  17153. @defvr {Scheme Variable} polkit-wheel-service
  17154. Service that adds the @code{wheel} group as admins to the Polkit
  17155. service. This makes it so that users in the @code{wheel} group are queried
  17156. for their own passwords when performing administrative actions instead of
  17157. @code{root}'s, similar to the behaviour used by @code{sudo}.
  17158. @end defvr
  17159. @defvr {Scheme Variable} upower-service-type
  17160. Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
  17161. system-wide monitor for power consumption and battery levels, with the given
  17162. configuration settings.
  17163. It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
  17164. notably used by GNOME.
  17165. @end defvr
  17166. @deftp {Data Type} upower-configuration
  17167. Data type representation the configuration for UPower.
  17168. @table @asis
  17169. @item @code{upower} (default: @var{upower})
  17170. Package to use for @code{upower}.
  17171. @item @code{watts-up-pro?} (default: @code{#f})
  17172. Enable the Watts Up Pro device.
  17173. @item @code{poll-batteries?} (default: @code{#t})
  17174. Enable polling the kernel for battery level changes.
  17175. @item @code{ignore-lid?} (default: @code{#f})
  17176. Ignore the lid state, this can be useful if it's incorrect on a device.
  17177. @item @code{use-percentage-for-policy?} (default: @code{#f})
  17178. Whether battery percentage based policy should be used. The default is to use
  17179. the time left, change to @code{#t} to use the percentage.
  17180. @item @code{percentage-low} (default: @code{10})
  17181. When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
  17182. at which the battery is considered low.
  17183. @item @code{percentage-critical} (default: @code{3})
  17184. When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
  17185. at which the battery is considered critical.
  17186. @item @code{percentage-action} (default: @code{2})
  17187. When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
  17188. at which action will be taken.
  17189. @item @code{time-low} (default: @code{1200})
  17190. When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
  17191. seconds at which the battery is considered low.
  17192. @item @code{time-critical} (default: @code{300})
  17193. When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
  17194. seconds at which the battery is considered critical.
  17195. @item @code{time-action} (default: @code{120})
  17196. When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
  17197. seconds at which action will be taken.
  17198. @item @code{critical-power-action} (default: @code{'hybrid-sleep})
  17199. The action taken when @code{percentage-action} or @code{time-action} is
  17200. reached (depending on the configuration of @code{use-percentage-for-policy?}).
  17201. Possible values are:
  17202. @itemize @bullet
  17203. @item
  17204. @code{'power-off}
  17205. @item
  17206. @code{'hibernate}
  17207. @item
  17208. @code{'hybrid-sleep}.
  17209. @end itemize
  17210. @end table
  17211. @end deftp
  17212. @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
  17213. Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
  17214. UDisks}, a @dfn{disk management} daemon that provides user interfaces
  17215. with notifications and ways to mount/unmount disks. Programs that talk
  17216. to UDisks include the @command{udisksctl} command, part of UDisks, and
  17217. GNOME Disks. Note that Udisks relies on the @command{mount} command, so
  17218. it will only be able to use the file-system utilities installed in the
  17219. system profile. For example if you want to be able to mount NTFS
  17220. file-systems in read and write fashion, you'll need to have
  17221. @code{ntfs-3g} installed system-wide.
  17222. @end deffn
  17223. @deffn {Scheme Variable} colord-service-type
  17224. This is the type of the service that runs @command{colord}, a system
  17225. service with a D-Bus
  17226. interface to manage the color profiles of input and output devices such as
  17227. screens and scanners. It is notably used by the GNOME Color Manager graphical
  17228. tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
  17229. site} for more information.
  17230. @end deffn
  17231. @cindex scanner access
  17232. @defvr {Scheme Variable} sane-service-type
  17233. This service provides access to scanners @i{via}
  17234. @uref{http://www.sane-project.org, SANE} by installing the necessary
  17235. udev rules. It is included in @code{%desktop-services} (@pxref{Desktop
  17236. Services}) and relies by default on @code{sane-backends-minimal} package
  17237. (see below) for hardware support.
  17238. @end defvr
  17239. @defvr {Scheme Variable} sane-backends-minimal
  17240. The default package which the @code{sane-service-type} installs. It
  17241. supports many recent scanners.
  17242. @end defvr
  17243. @defvr {Scheme Variable} sane-backends
  17244. This package includes support for all scanners that
  17245. @code{sane-backends-minimal} supports, plus older Hewlett-Packard
  17246. scanners supported by @code{hplip} package. In order to use this on
  17247. a system which relies on @code{%desktop-services}, you may use
  17248. @code{modify-services} (@pxref{Service Reference,
  17249. @code{modify-services}}) as illustrated below:
  17250. @lisp
  17251. (use-modules (gnu))
  17252. (use-service-modules
  17253. @dots{}
  17254. desktop)
  17255. (use-package-modules
  17256. @dots{}
  17257. scanner)
  17258. (define %my-desktop-services
  17259. ;; List of desktop services that supports a broader range of scanners.
  17260. (modify-services %desktop-services
  17261. (sane-service-type _ => sane-backends)))
  17262. (operating-system
  17263. @dots{}
  17264. (services %my-desktop-services))
  17265. @end lisp
  17266. @end defvr
  17267. @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
  17268. Return a configuration allowing an application to access GeoClue
  17269. location data. @var{name} is the Desktop ID of the application, without
  17270. the @code{.desktop} part. If @var{allowed?} is true, the application
  17271. will have access to location information by default. The boolean
  17272. @var{system?} value indicates whether an application is a system component
  17273. or not. Finally @var{users} is a list of UIDs of all users for which
  17274. this application is allowed location info access. An empty users list
  17275. means that all users are allowed.
  17276. @end deffn
  17277. @defvr {Scheme Variable} %standard-geoclue-applications
  17278. The standard list of well-known GeoClue application configurations,
  17279. granting authority to the GNOME date-and-time utility to ask for the
  17280. current location in order to set the time zone, and allowing the
  17281. IceCat and Epiphany web browsers to request location information.
  17282. IceCat and Epiphany both query the user before allowing a web page to
  17283. know the user's location.
  17284. @end defvr
  17285. @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
  17286. [#:whitelist '()] @
  17287. [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
  17288. [#:submit-data? #f]
  17289. [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
  17290. [#:submission-nick "geoclue"] @
  17291. [#:applications %standard-geoclue-applications]
  17292. Return a service that runs the GeoClue location service. This service
  17293. provides a D-Bus interface to allow applications to request access to a
  17294. user's physical location, and optionally to add information to online
  17295. location databases. See
  17296. @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
  17297. web site} for more information.
  17298. @end deffn
  17299. @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
  17300. [@w{#:auto-enable? #f}]
  17301. Return a service that runs the @command{bluetoothd} daemon, which
  17302. manages all the Bluetooth devices and provides a number of D-Bus
  17303. interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
  17304. powered automatically at boot, which can be useful when using a
  17305. bluetooth keyboard or mouse.
  17306. Users need to be in the @code{lp} group to access the D-Bus service.
  17307. @end deffn
  17308. @deffn {Scheme Variable} bluetooth-service-type
  17309. This is the type for the @uref{https://bluez.org/, Linux Bluetooth Protocol
  17310. Stack} (BlueZ) system, which generates the @file{/etc/bluetooth/main.conf}
  17311. configuration file. The value for this type is a @command{bluetooth-configuration}
  17312. record as in this example:
  17313. @lisp
  17314. (service bluetooth-service-type)
  17315. @end lisp
  17316. See below for details about @code{bluetooth-configuration}.
  17317. @end deffn
  17318. @deftp {Data Type} bluetooth-configuration
  17319. Data type representing the configuration for @code{bluetooth-service}.
  17320. @table @asis
  17321. @item @code{bluez} (default: @code{bluez})
  17322. @code{bluez} package to use.
  17323. @item @code{name} (default: @code{"BlueZ"})
  17324. Default adapter name.
  17325. @item @code{class} (default: @code{#x000000})
  17326. Default device class. Only the major and minor device class bits are considered.
  17327. @item @code{discoverable-timeout} (default: @code{180})
  17328. How long to stay in discoverable mode before going back to non-discoverable. The
  17329. value is in seconds.
  17330. @item @code{always-pairable?} (default: @code{#f})
  17331. Always allow pairing even if there are no agents registered.
  17332. @item @code{pairable-timeout} (default: @code{0})
  17333. How long to stay in pairable mode before going back to non-discoverable. The
  17334. value is in seconds.
  17335. @item @code{device-id} (default: @code{#f})
  17336. Use vendor id source (assigner), vendor, product and version information for
  17337. DID profile support. The values are separated by ":" and @var{assigner}, @var{VID},
  17338. @var{PID} and @var{version}.
  17339. Possible values are:
  17340. @itemize @bullet
  17341. @item
  17342. @code{#f} to disable it,
  17343. @item
  17344. @code{"assigner:1234:5678:abcd"}, where @var{assigner} is either @code{usb} (default)
  17345. or @code{bluetooth}.
  17346. @end itemize
  17347. @item @code{reverse-service-discovery?} (default: @code{#t})
  17348. Do reverse service discovery for previously unknown devices that connect to
  17349. us. For BR/EDR this option is really only needed for qualification since the
  17350. BITE tester doesn't like us doing reverse SDP for some test cases, for LE
  17351. this disables the GATT client functionally so it can be used in system which
  17352. can only operate as peripheral.
  17353. @item @code{name-resolving?} (default: @code{#t})
  17354. Enable name resolving after inquiry. Set it to @code{#f} if you don't need
  17355. remote devices name and want shorter discovery cycle.
  17356. @item @code{debug-keys?} (default: @code{#f})
  17357. Enable runtime persistency of debug link keys. Default is false which makes
  17358. debug link keys valid only for the duration of the connection that they were
  17359. created for.
  17360. @item @code{controller-mode} (default: @code{'dual})
  17361. Restricts all controllers to the specified transport. @code{'dual} means both
  17362. BR/EDR and LE are enabled (if supported by the hardware).
  17363. Possible values are:
  17364. @itemize @bullet
  17365. @item
  17366. @code{'dual}
  17367. @item
  17368. @code{'bredr}
  17369. @item
  17370. @code{'le}
  17371. @end itemize
  17372. @item @code{multi-profile} (default: @code{'off})
  17373. Enables Multi Profile Specification support. This allows to specify if system
  17374. supports only Multiple Profiles Single Device (MPSD) configuration or both
  17375. Multiple Profiles Single Device (MPSD) and Multiple Profiles Multiple Devices
  17376. (MPMD) configurations.
  17377. Possible values are:
  17378. @itemize @bullet
  17379. @item
  17380. @code{'off}
  17381. @item
  17382. @code{'single}
  17383. @item
  17384. @code{'multiple}
  17385. @end itemize
  17386. @item @code{fast-connectable?} (default: @code{#f})
  17387. Permanently enables the Fast Connectable setting for adapters that support
  17388. it. When enabled other devices can connect faster to us, however the
  17389. tradeoff is increased power consumptions. This feature will fully work only
  17390. on kernel version 4.1 and newer.
  17391. @item @code{privacy} (default: @code{'off})
  17392. Default privacy settings.
  17393. @itemize @bullet
  17394. @item
  17395. @code{'off}: Disable local privacy
  17396. @item
  17397. @code{'network/on}: A device will only accept advertising packets from peer
  17398. devices that contain private addresses. It may not be compatible with some
  17399. legacy devices since it requires the use of RPA(s) all the time
  17400. @item
  17401. @code{'device}: A device in device privacy mode is only concerned about the
  17402. privacy of the device and will accept advertising packets from peer devices
  17403. that contain their Identity Address as well as ones that contain a private
  17404. address, even if the peer device has distributed its IRK in the past
  17405. @end itemize
  17406. and additionally, if @var{controller-mode} is set to @code{'dual}:
  17407. @itemize @bullet
  17408. @item
  17409. @code{'limited-network}: Apply Limited Discoverable Mode to advertising, which
  17410. follows the same policy as to BR/EDR that publishes the identity address when
  17411. discoverable, and Network Privacy Mode for scanning
  17412. @item
  17413. @code{'limited-device}: Apply Limited Discoverable Mode to advertising, which
  17414. follows the same policy as to BR/EDR that publishes the identity address when
  17415. discoverable, and Device Privacy Mode for scanning.
  17416. @end itemize
  17417. @item @code{just-works-repairing} (default: @code{'never})
  17418. Specify the policy to the JUST-WORKS repairing initiated by peer.
  17419. Possible values:
  17420. @itemize @bullet
  17421. @item
  17422. @code{'never}
  17423. @item
  17424. @code{'confirm}
  17425. @item
  17426. @code{'always}
  17427. @end itemize
  17428. @item @code{temporary-timeout} (default: @code{30})
  17429. How long to keep temporary devices around. The value is in seconds. @code{0}
  17430. disables the timer completely.
  17431. @item @code{refresh-discovery?} (default: @code{#t})
  17432. Enables the device to issue an SDP request to update known services when
  17433. profile is connected.
  17434. @item @code{experimental} (default: @code{#f})
  17435. Enables experimental features and interfaces, alternatively a list of UUIDs
  17436. can be given.
  17437. Possible values:
  17438. @itemize @bullet
  17439. @item
  17440. @code{#t}
  17441. @item
  17442. @code{#f}
  17443. @item
  17444. @code{(list (uuid <uuid-1>) (uuid <uuid-2>) ...)}.
  17445. @end itemize
  17446. List of possible UUIDs:
  17447. @itemize @bullet
  17448. @item
  17449. @code{d4992530-b9ec-469f-ab01-6c481c47da1c}: BlueZ Experimental Debug,
  17450. @item
  17451. @code{671b10b5-42c0-4696-9227-eb28d1b049d6}: BlueZ Experimental Simultaneous Central and Peripheral,
  17452. @item
  17453. @code{"15c0a148-c273-11ea-b3de-0242ac130004}: BlueZ Experimental LL privacy,
  17454. @item
  17455. @code{330859bc-7506-492d-9370-9a6f0614037f}: BlueZ Experimental Bluetooth Quality Report,
  17456. @item
  17457. @code{a6695ace-ee7f-4fb9-881a-5fac66c629af}: BlueZ Experimental Offload Codecs.
  17458. @end itemize
  17459. @item @code{remote-name-request-retry-delay} (default: @code{300})
  17460. The duration to avoid retrying to resolve a peer's name, if the previous
  17461. try failed.
  17462. @item @code{page-scan-type} (default: @code{#f})
  17463. BR/EDR Page scan activity type.
  17464. @item @code{page-scan-interval} (default: @code{#f})
  17465. BR/EDR Page scan activity interval.
  17466. @item @code{page-scan-window} (default: @code{#f})
  17467. BR/EDR Page scan activity window.
  17468. @item @code{inquiry-scan-type} (default: @code{#f})
  17469. BR/EDR Inquiry scan activity type.
  17470. @item @code{inquiry-scan-interval} (default: @code{#f})
  17471. BR/EDR Inquiry scan activity interval.
  17472. @item @code{inquiry-scan-window} (default: @code{#f})
  17473. BR/EDR Inquiry scan activity window.
  17474. @item @code{link-supervision-timeout} (default: @code{#f})
  17475. BR/EDR Link supervision timeout.
  17476. @item @code{page-timeout} (default: @code{#f})
  17477. BR/EDR Page timeout.
  17478. @item @code{min-sniff-interval} (default: @code{#f})
  17479. BR/EDR minimum sniff interval.
  17480. @item @code{max-sniff-interval} (default: @code{#f})
  17481. BR/EDR maximum sniff interval.
  17482. @item @code{min-advertisement-interval} (default: @code{#f})
  17483. LE minimum advertisement interval (used for legacy advertisement only).
  17484. @item @code{max-advertisement-interval} (default: @code{#f})
  17485. LE maximum advertisement interval (used for legacy advertisement only).
  17486. @item @code{multi-advertisement-rotation-interval} (default: @code{#f})
  17487. LE multiple advertisement rotation interval.
  17488. @item @code{scan-interval-auto-connect} (default: @code{#f})
  17489. LE scanning interval used for passive scanning supporting auto connect.
  17490. @item @code{scan-window-auto-connect} (default: @code{#f})
  17491. LE scanning window used for passive scanning supporting auto connect.
  17492. @item @code{scan-interval-suspend} (default: @code{#f})
  17493. LE scanning interval used for active scanning supporting wake from suspend.
  17494. @item @code{scan-window-suspend} (default: @code{#f})
  17495. LE scanning window used for active scanning supporting wake from suspend.
  17496. @item @code{scan-interval-discovery} (default: @code{#f})
  17497. LE scanning interval used for active scanning supporting discovery.
  17498. @item @code{scan-window-discovery} (default: @code{#f})
  17499. LE scanning window used for active scanning supporting discovery.
  17500. @item @code{scan-interval-adv-monitor} (default: @code{#f})
  17501. LE scanning interval used for passive scanning supporting the advertisement monitor APIs.
  17502. @item @code{scan-window-adv-monitor} (default: @code{#f})
  17503. LE scanning window used for passive scanning supporting the advertisement monitor APIs.
  17504. @item @code{scan-interval-connect} (default: @code{#f})
  17505. LE scanning interval used for connection establishment.
  17506. @item @code{scan-window-connect} (default: @code{#f})
  17507. LE scanning window used for connection establishment.
  17508. @item @code{min-connection-interval} (default: @code{#f})
  17509. LE default minimum connection interval. This value is superceeded by any specific
  17510. value provided via the Load Connection Parameters interface.
  17511. @item @code{max-connection-interval} (default: @code{#f})
  17512. LE default maximum connection interval. This value is superceeded by any specific
  17513. value provided via the Load Connection Parameters interface.
  17514. @item @code{connection-latency} (default: @code{#f})
  17515. LE default connection latency. This value is superceeded by any specific
  17516. value provided via the Load Connection Parameters interface.
  17517. @item @code{connection-supervision-timeout} (default: @code{#f})
  17518. LE default connection supervision timeout. This value is superceeded by any specific
  17519. value provided via the Load Connection Parameters interface.
  17520. @item @code{autoconnect-timeout} (default: @code{#f})
  17521. LE default autoconnect timeout. This value is superceeded by any specific
  17522. value provided via the Load Connection Parameters interface.
  17523. @item @code{adv-mon-allowlist-scan-duration} (default: @code{300})
  17524. Allowlist scan duration during interleaving scan. Only used when scanning for ADV
  17525. monitors. The units are msec.
  17526. @item @code{adv-mon-no-filter-scan-duration} (default: @code{500})
  17527. No filter scan duration during interleaving scan. Only used when scanning for ADV
  17528. monitors. The units are msec.
  17529. @item @code{enable-adv-mon-interleave-scan?} (default: @code{#t})
  17530. Enable/Disable Advertisement Monitor interleave scan for power saving.
  17531. @item @code{cache} (default: @code{'always})
  17532. GATT attribute cache.
  17533. Possible values are:
  17534. @itemize @bullet
  17535. @item
  17536. @code{'always}: Always cache attributes even for devices not paired, this is
  17537. recommended as it is best for interoperability, with more consistent
  17538. reconnection times and enables proper tracking of notifications for all
  17539. devices
  17540. @item
  17541. @code{'yes}: Only cache attributes of paired devices
  17542. @item
  17543. @code{'no}: Never cache attributes.
  17544. @end itemize
  17545. @item @code{key-size} (default: @code{0})
  17546. Minimum required Encryption Key Size for accessing secured characteristics.
  17547. Possible values are:
  17548. @itemize @bullet
  17549. @item
  17550. @code{0}: Don't care
  17551. @item
  17552. @code{7 <= N <= 16}
  17553. @end itemize
  17554. @item @code{exchange-mtu} (default: @code{517})
  17555. Exchange MTU size. Possible values are:
  17556. @itemize @bullet
  17557. @item
  17558. @code{23 <= N <= 517}
  17559. @end itemize
  17560. @item @code{att-channels} (default: @code{3})
  17561. Number of ATT channels. Possible values are:
  17562. @itemize @bullet
  17563. @item
  17564. @code{1}: Disables EATT
  17565. @item
  17566. @code{2 <= N <= 5}
  17567. @end itemize
  17568. @item @code{session-mode} (default: @code{'basic})
  17569. AVDTP L2CAP signalling channel mode.
  17570. Possible values are:
  17571. @itemize @bullet
  17572. @item
  17573. @code{'basic}: Use L2CAP basic mode
  17574. @item
  17575. @code{'ertm}: Use L2CAP enhanced retransmission mode.
  17576. @end itemize
  17577. @item @code{stream-mode} (default: @code{'basic})
  17578. AVDTP L2CAP transport channel mode.
  17579. Possible values are:
  17580. @itemize @bullet
  17581. @item
  17582. @code{'basic}: Use L2CAP basic mode
  17583. @item
  17584. @code{'streaming}: Use L2CAP streaming mode.
  17585. @end itemize
  17586. @item @code{reconnect-uuids} (default: @code{'()})
  17587. The ReconnectUUIDs defines the set of remote services that should try
  17588. to be reconnected to in case of a link loss (link supervision
  17589. timeout). The policy plugin should contain a sane set of values by
  17590. default, but this list can be overridden here. By setting the list to
  17591. empty the reconnection feature gets disabled.
  17592. Possible values:
  17593. @itemize @bullet
  17594. @item
  17595. @code{'()}
  17596. @item
  17597. @code{(list (uuid <uuid-1>) (uuid <uuid-2>) ...)}.
  17598. @end itemize
  17599. @item @code{reconnect-attempts} (default: @code{7})
  17600. Defines the number of attempts to reconnect after a link lost. Setting
  17601. the value to 0 disables reconnecting feature.
  17602. @item @code{reconnect-intervals} (default: @code{'(1 2 4 8 16 32 64)})
  17603. Defines a list of intervals in seconds to use in between attempts. If
  17604. the number of attempts defined in @var{reconnect-attempts} is bigger than
  17605. the list of intervals the last interval is repeated until the last attempt.
  17606. @item @code{auto-enable?} (default: @code{#f})
  17607. Defines option to enable all controllers when they are found. This includes
  17608. adapters present on start as well as adapters that are plugged in later on.
  17609. @item @code{resume-delay} (default: @code{2})
  17610. Audio devices that were disconnected due to suspend will be reconnected on
  17611. resume. @var{resume-delay} determines the delay between when the controller
  17612. resumes from suspend and a connection attempt is made. A longer delay is
  17613. better for better co-existence with Wi-Fi. The value is in seconds.
  17614. @item @code{rssi-sampling-period} (default: @code{#xFF})
  17615. Default RSSI Sampling Period. This is used when a client registers an
  17616. advertisement monitor and leaves the RSSISamplingPeriod unset.
  17617. Possible values are:
  17618. @itemize @bullet
  17619. @item
  17620. @code{#x0}: Report all advertisements
  17621. @item
  17622. @code{N = #xXX}: Report advertisements every N x 100 msec (range: #x01 to #xFE)
  17623. @item
  17624. @code{#xFF}: Report only one advertisement per device during monitoring period.
  17625. @end itemize
  17626. @end table
  17627. @end deftp
  17628. @defvr {Scheme Variable} gnome-keyring-service-type
  17629. This is the type of the service that adds the
  17630. @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
  17631. value is a @code{gnome-keyring-configuration} object (see below).
  17632. This service adds the @code{gnome-keyring} package to the system profile
  17633. and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
  17634. a user's login keyring when they log in or setting its password with passwd.
  17635. @end defvr
  17636. @deftp {Data Type} gnome-keyring-configuration
  17637. Configuration record for the GNOME Keyring service.
  17638. @table @asis
  17639. @item @code{keyring} (default: @code{gnome-keyring})
  17640. The GNOME keyring package to use.
  17641. @item @code{pam-services}
  17642. A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
  17643. services to extend, where @var{service} is the name of an existing
  17644. service to extend and @var{kind} is one of @code{login} or
  17645. @code{passwd}.
  17646. If @code{login} is given, it adds an optional
  17647. @code{pam_gnome_keyring.so} to the auth block without arguments and to
  17648. the session block with @code{auto_start}. If @code{passwd} is given, it
  17649. adds an optional @code{pam_gnome_keyring.so} to the password block
  17650. without arguments.
  17651. By default, this field contains ``gdm-password'' with the value @code{login}
  17652. and ``passwd'' is with the value @code{passwd}.
  17653. @end table
  17654. @end deftp
  17655. @node Sound Services
  17656. @subsection Sound Services
  17657. @cindex sound support
  17658. @cindex ALSA
  17659. @cindex PulseAudio, sound support
  17660. The @code{(gnu services sound)} module provides a service to configure the
  17661. Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
  17662. preferred ALSA output driver.
  17663. @deffn {Scheme Variable} alsa-service-type
  17664. This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
  17665. Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
  17666. configuration file. The value for this type is a @command{alsa-configuration}
  17667. record as in this example:
  17668. @lisp
  17669. (service alsa-service-type)
  17670. @end lisp
  17671. See below for details about @code{alsa-configuration}.
  17672. @end deffn
  17673. @deftp {Data Type} alsa-configuration
  17674. Data type representing the configuration for @code{alsa-service}.
  17675. @table @asis
  17676. @item @code{alsa-plugins} (default: @var{alsa-plugins})
  17677. @code{alsa-plugins} package to use.
  17678. @item @code{pulseaudio?} (default: @var{#t})
  17679. Whether ALSA applications should transparently be made to use the
  17680. @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
  17681. Using PulseAudio allows you to run several sound-producing applications
  17682. at the same time and to individual control them @i{via}
  17683. @command{pavucontrol}, among other things.
  17684. @item @code{extra-options} (default: @var{""})
  17685. String to append to the @file{/etc/asound.conf} file.
  17686. @end table
  17687. @end deftp
  17688. Individual users who want to override the system configuration of ALSA can do
  17689. it with the @file{~/.asoundrc} file:
  17690. @example
  17691. # In guix, we have to specify the absolute path for plugins.
  17692. pcm_type.jack @{
  17693. lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
  17694. @}
  17695. # Routing ALSA to jack:
  17696. # <http://jackaudio.org/faq/routing_alsa.html>.
  17697. pcm.rawjack @{
  17698. type jack
  17699. playback_ports @{
  17700. 0 system:playback_1
  17701. 1 system:playback_2
  17702. @}
  17703. capture_ports @{
  17704. 0 system:capture_1
  17705. 1 system:capture_2
  17706. @}
  17707. @}
  17708. pcm.!default @{
  17709. type plug
  17710. slave @{
  17711. pcm "rawjack"
  17712. @}
  17713. @}
  17714. @end example
  17715. See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
  17716. details.
  17717. @deffn {Scheme Variable} pulseaudio-service-type
  17718. This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
  17719. sound server. It exists to allow system overrides of the default settings
  17720. via @code{pulseaudio-configuration}, see below.
  17721. @quotation Warning
  17722. This service overrides per-user configuration files. If you want
  17723. PulseAudio to honor configuration files in @file{~/.config/pulse} you
  17724. have to unset the environment variables @env{PULSE_CONFIG} and
  17725. @env{PULSE_CLIENTCONFIG} in your @file{~/.bash_profile}.
  17726. @end quotation
  17727. @quotation Warning
  17728. This service on its own does not ensure, that the @code{pulseaudio} package
  17729. exists on your machine. It merely adds configuration files for it, as
  17730. detailed below. In the (admittedly unlikely) case, that you find yourself
  17731. without a @code{pulseaudio} package, consider enabling it through the
  17732. @code{alsa-service-type} above.
  17733. @end quotation
  17734. @end deffn
  17735. @deftp {Data Type} pulseaudio-configuration
  17736. Data type representing the configuration for @code{pulseaudio-service}.
  17737. @table @asis
  17738. @item @code{client-conf} (default: @code{'()})
  17739. List of settings to set in @file{client.conf}.
  17740. Accepts a list of strings or symbol-value pairs. A string will be
  17741. inserted as-is with a newline added. A pair will be formatted as
  17742. ``key = value'', again with a newline added.
  17743. @item @code{daemon-conf} (default: @code{'((flat-volumes . no))})
  17744. List of settings to set in @file{daemon.conf}, formatted just like
  17745. @var{client-conf}.
  17746. @item @code{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
  17747. Script file to use as @file{default.pa}. In case the
  17748. @code{extra-script-files} field below is used, an @code{.include}
  17749. directive pointing to @file{/etc/pulse/default.pa.d} is appended to the
  17750. provided script.
  17751. @item @code{extra-script-files} (default: @code{'())})
  17752. A list of file-like objects defining extra PulseAudio scripts to run at
  17753. the initialization of the @command{pulseaudio} daemon, after the main
  17754. @code{script-file}. The scripts are deployed to the
  17755. @file{/etc/pulse/default.pa.d} directory; they should have the
  17756. @samp{.pa} file name extension. For a reference of the available
  17757. commands, refer to @command{man pulse-cli-syntax}.
  17758. @item @code{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
  17759. Script file to use as @file{system.pa}.
  17760. @end table
  17761. The example below sets the default PulseAudio card profile, the default
  17762. sink and the default source to use for a old SoundBlaster Audigy sound
  17763. card:
  17764. @lisp
  17765. (pulseaudio-configuration
  17766. (extra-script-files
  17767. (list (plain-file "audigy.pa"
  17768. (string-append "\
  17769. set-card-profile alsa_card.pci-0000_01_01.0 \
  17770. output:analog-surround-40+input:analog-mono
  17771. set-default-source alsa_input.pci-0000_01_01.0.analog-mono
  17772. set-default-sink alsa_output.pci-0000_01_01.0.analog-surround-40\n")))))
  17773. @end lisp
  17774. Note that @code{pulseaudio-service-type} is part of
  17775. @code{%desktop-services}; if your operating system declaration was
  17776. derived from one of the desktop templates, you'll want to adjust the
  17777. above example to modify the existing @code{pulseaudio-service-type} via
  17778. @code{modify-services} (@pxref{Service Reference,
  17779. @code{modify-services}}), instead of defining a new one.
  17780. @end deftp
  17781. @deffn {Scheme Variable} ladspa-service-type
  17782. This service sets the @var{LADSPA_PATH} variable, so that programs, which
  17783. respect it, e.g. PulseAudio, can load LADSPA plugins.
  17784. The following example will setup the service to enable modules from the
  17785. @code{swh-plugins} package:
  17786. @lisp
  17787. (service ladspa-service-type
  17788. (ladspa-configuration (plugins (list swh-plugins))))
  17789. @end lisp
  17790. See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
  17791. details.
  17792. @end deffn
  17793. @node Database Services
  17794. @subsection Database Services
  17795. @cindex database
  17796. @cindex SQL
  17797. The @code{(gnu services databases)} module provides the following services.
  17798. @subsubheading PostgreSQL
  17799. The following example describes a PostgreSQL service with the default
  17800. configuration.
  17801. @lisp
  17802. (service postgresql-service-type
  17803. (postgresql-configuration
  17804. (postgresql postgresql-10)))
  17805. @end lisp
  17806. If the services fails to start, it may be due to an incompatible
  17807. cluster already present in @var{data-directory}. Adjust it (or, if you
  17808. don't need the cluster anymore, delete @var{data-directory}), then
  17809. restart the service.
  17810. Peer authentication is used by default and the @code{postgres} user
  17811. account has no shell, which prevents the direct execution of @code{psql}
  17812. commands as this user. To use @code{psql}, you can temporarily log in
  17813. as @code{postgres} using a shell, create a PostgreSQL superuser with the
  17814. same name as one of the system users and then create the associated
  17815. database.
  17816. @example
  17817. sudo -u postgres -s /bin/sh
  17818. createuser --interactive
  17819. createdb $MY_USER_LOGIN # Replace appropriately.
  17820. @end example
  17821. @deftp {Data Type} postgresql-configuration
  17822. Data type representing the configuration for the
  17823. @code{postgresql-service-type}.
  17824. @table @asis
  17825. @item @code{postgresql}
  17826. PostgreSQL package to use for the service.
  17827. @item @code{port} (default: @code{5432})
  17828. Port on which PostgreSQL should listen.
  17829. @item @code{locale} (default: @code{"en_US.utf8"})
  17830. Locale to use as the default when creating the database cluster.
  17831. @item @code{config-file} (default: @code{(postgresql-config-file)})
  17832. The configuration file to use when running PostgreSQL@. The default
  17833. behaviour uses the postgresql-config-file record with the default values
  17834. for the fields.
  17835. @item @code{log-directory} (default: @code{"/var/log/postgresql"})
  17836. The directory where @command{pg_ctl} output will be written in a file
  17837. named @code{"pg_ctl.log"}. This file can be useful to debug PostgreSQL
  17838. configuration errors for instance.
  17839. @item @code{data-directory} (default: @code{"/var/lib/postgresql/data"})
  17840. Directory in which to store the data.
  17841. @item @code{extension-packages} (default: @code{'()})
  17842. @cindex postgresql extension-packages
  17843. Additional extensions are loaded from packages listed in
  17844. @var{extension-packages}. Extensions are available at runtime. For instance,
  17845. to create a geographic database using the @code{postgis} extension, a user can
  17846. configure the postgresql-service as in this example:
  17847. @cindex postgis
  17848. @lisp
  17849. (use-package-modules databases geo)
  17850. (operating-system
  17851. ...
  17852. ;; postgresql is required to run `psql' but postgis is not required for
  17853. ;; proper operation.
  17854. (packages (cons* postgresql %base-packages))
  17855. (services
  17856. (cons*
  17857. (service postgresql-service-type
  17858. (postgresql-configuration
  17859. (postgresql postgresql-10)
  17860. (extension-packages (list postgis))))
  17861. %base-services)))
  17862. @end lisp
  17863. Then the extension becomes visible and you can initialise an empty geographic
  17864. database in this way:
  17865. @example
  17866. psql -U postgres
  17867. > create database postgistest;
  17868. > \connect postgistest;
  17869. > create extension postgis;
  17870. > create extension postgis_topology;
  17871. @end example
  17872. There is no need to add this field for contrib extensions such as hstore or
  17873. dblink as they are already loadable by postgresql. This field is only
  17874. required to add extensions provided by other packages.
  17875. @end table
  17876. @end deftp
  17877. @deftp {Data Type} postgresql-config-file
  17878. Data type representing the PostgreSQL configuration file. As shown in
  17879. the following example, this can be used to customize the configuration
  17880. of PostgreSQL@. Note that you can use any G-expression or filename in
  17881. place of this record, if you already have a configuration file you'd
  17882. like to use for example.
  17883. @lisp
  17884. (service postgresql-service-type
  17885. (postgresql-configuration
  17886. (config-file
  17887. (postgresql-config-file
  17888. (log-destination "stderr")
  17889. (hba-file
  17890. (plain-file "pg_hba.conf"
  17891. "
  17892. local all all trust
  17893. host all all 127.0.0.1/32 md5
  17894. host all all ::1/128 md5"))
  17895. (extra-config
  17896. '(("session_preload_libraries" "auto_explain")
  17897. ("random_page_cost" 2)
  17898. ("auto_explain.log_min_duration" "100 ms")
  17899. ("work_mem" "500 MB")
  17900. ("logging_collector" #t)
  17901. ("log_directory" "/var/log/postgresql")))))))
  17902. @end lisp
  17903. @table @asis
  17904. @item @code{log-destination} (default: @code{"syslog"})
  17905. The logging method to use for PostgreSQL@. Multiple values are accepted,
  17906. separated by commas.
  17907. @item @code{hba-file} (default: @code{%default-postgres-hba})
  17908. Filename or G-expression for the host-based authentication
  17909. configuration.
  17910. @item @code{ident-file} (default: @code{%default-postgres-ident})
  17911. Filename or G-expression for the user name mapping configuration.
  17912. @item @code{socket-directory} (default: @code{"/var/run/postgresql"})
  17913. Specifies the directory of the Unix-domain socket(s) on which PostgreSQL
  17914. is to listen for connections from client applications. If set to
  17915. @code{""} PostgreSQL does not listen on any Unix-domain sockets, in
  17916. which case only TCP/IP sockets can be used to connect to the server.
  17917. By default, the @code{#false} value means the PostgreSQL default value
  17918. will be used, which is currently @samp{/tmp}.
  17919. @item @code{extra-config} (default: @code{'()})
  17920. List of additional keys and values to include in the PostgreSQL config
  17921. file. Each entry in the list should be a list where the first element
  17922. is the key, and the remaining elements are the values.
  17923. The values can be numbers, booleans or strings and will be mapped to
  17924. PostgreSQL parameters types @code{Boolean}, @code{String},
  17925. @code{Numeric}, @code{Numeric with Unit} and @code{Enumerated} described
  17926. @uref{https://www.postgresql.org/docs/current/config-setting.html,
  17927. here}.
  17928. @end table
  17929. @end deftp
  17930. @deffn {Scheme Variable} postgresql-role-service-type
  17931. This service allows to create PostgreSQL roles and databases after
  17932. PostgreSQL service start. Here is an example of its use.
  17933. @lisp
  17934. (service postgresql-role-service-type
  17935. (postgresql-role-configuration
  17936. (roles
  17937. (list (postgresql-role
  17938. (name "test")
  17939. (create-database? #t))))))
  17940. @end lisp
  17941. This service can be extended with extra roles, as in this
  17942. example:
  17943. @lisp
  17944. (service-extension postgresql-role-service-type
  17945. (const (postgresql-role
  17946. (name "alice")
  17947. (create-database? #t))))
  17948. @end lisp
  17949. @end deffn
  17950. @deftp {Data Type} postgresql-role
  17951. PostgreSQL manages database access permissions using the concept of
  17952. roles. A role can be thought of as either a database user, or a group
  17953. of database users, depending on how the role is set up. Roles can own
  17954. database objects (for example, tables) and can assign privileges on
  17955. those objects to other roles to control who has access to which objects.
  17956. @table @asis
  17957. @item @code{name}
  17958. The role name.
  17959. @item @code{permissions} (default: @code{'(createdb login)})
  17960. The role permissions list. Supported permissions are @code{bypassrls},
  17961. @code{createdb}, @code{createrole}, @code{login}, @code{replication} and
  17962. @code{superuser}.
  17963. @item @code{create-database?} (default: @code{#f})
  17964. Whether to create a database with the same name as the role.
  17965. @end table
  17966. @end deftp
  17967. @deftp {Data Type} postgresql-role-configuration
  17968. Data type representing the configuration of
  17969. @var{postgresql-role-service-type}.
  17970. @table @asis
  17971. @item @code{host} (default: @code{"/var/run/postgresql"})
  17972. The PostgreSQL host to connect to.
  17973. @item @code{log} (default: @code{"/var/log/postgresql_roles.log"})
  17974. File name of the log file.
  17975. @item @code{roles} (default: @code{'()})
  17976. The initial PostgreSQL roles to create.
  17977. @end table
  17978. @end deftp
  17979. @subsubheading MariaDB/MySQL
  17980. @defvr {Scheme Variable} mysql-service-type
  17981. This is the service type for a MySQL or MariaDB database server. Its value
  17982. is a @code{mysql-configuration} object that specifies which package to use,
  17983. as well as various settings for the @command{mysqld} daemon.
  17984. @end defvr
  17985. @deftp {Data Type} mysql-configuration
  17986. Data type representing the configuration of @var{mysql-service-type}.
  17987. @table @asis
  17988. @item @code{mysql} (default: @var{mariadb})
  17989. Package object of the MySQL database server, can be either @var{mariadb}
  17990. or @var{mysql}.
  17991. For MySQL, a temporary root password will be displayed at activation time.
  17992. For MariaDB, the root password is empty.
  17993. @item @code{bind-address} (default: @code{"127.0.0.1"})
  17994. The IP on which to listen for network connections. Use @code{"0.0.0.0"}
  17995. to bind to all available network interfaces.
  17996. @item @code{port} (default: @code{3306})
  17997. TCP port on which the database server listens for incoming connections.
  17998. @item @code{socket} (default: @code{"/run/mysqld/mysqld.sock"})
  17999. Socket file to use for local (non-network) connections.
  18000. @item @code{extra-content} (default: @code{""})
  18001. Additional settings for the @file{my.cnf} configuration file.
  18002. @item @code{extra-environment} (default: @code{#~'()})
  18003. List of environment variables passed to the @command{mysqld} process.
  18004. @item @code{auto-upgrade?} (default: @code{#t})
  18005. Whether to automatically run @command{mysql_upgrade} after starting the
  18006. service. This is necessary to upgrade the @dfn{system schema} after
  18007. ``major'' updates (such as switching from MariaDB 10.4 to 10.5), but can
  18008. be disabled if you would rather do that manually.
  18009. @end table
  18010. @end deftp
  18011. @subsubheading Memcached
  18012. @defvr {Scheme Variable} memcached-service-type
  18013. This is the service type for the @uref{https://memcached.org/,
  18014. Memcached} service, which provides a distributed in memory cache. The
  18015. value for the service type is a @code{memcached-configuration} object.
  18016. @end defvr
  18017. @lisp
  18018. (service memcached-service-type)
  18019. @end lisp
  18020. @deftp {Data Type} memcached-configuration
  18021. Data type representing the configuration of memcached.
  18022. @table @asis
  18023. @item @code{memcached} (default: @code{memcached})
  18024. The Memcached package to use.
  18025. @item @code{interfaces} (default: @code{'("0.0.0.0")})
  18026. Network interfaces on which to listen.
  18027. @item @code{tcp-port} (default: @code{11211})
  18028. Port on which to accept connections.
  18029. @item @code{udp-port} (default: @code{11211})
  18030. Port on which to accept UDP connections on, a value of 0 will disable
  18031. listening on a UDP socket.
  18032. @item @code{additional-options} (default: @code{'()})
  18033. Additional command line options to pass to @code{memcached}.
  18034. @end table
  18035. @end deftp
  18036. @subsubheading Redis
  18037. @defvr {Scheme Variable} redis-service-type
  18038. This is the service type for the @uref{https://redis.io/, Redis}
  18039. key/value store, whose value is a @code{redis-configuration} object.
  18040. @end defvr
  18041. @deftp {Data Type} redis-configuration
  18042. Data type representing the configuration of redis.
  18043. @table @asis
  18044. @item @code{redis} (default: @code{redis})
  18045. The Redis package to use.
  18046. @item @code{bind} (default: @code{"127.0.0.1"})
  18047. Network interface on which to listen.
  18048. @item @code{port} (default: @code{6379})
  18049. Port on which to accept connections on, a value of 0 will disable
  18050. listening on a TCP socket.
  18051. @item @code{working-directory} (default: @code{"/var/lib/redis"})
  18052. Directory in which to store the database and related files.
  18053. @end table
  18054. @end deftp
  18055. @node Mail Services
  18056. @subsection Mail Services
  18057. @cindex mail
  18058. @cindex email
  18059. The @code{(gnu services mail)} module provides Guix service definitions
  18060. for email services: IMAP, POP3, and LMTP servers, as well as mail
  18061. transport agents (MTAs). Lots of acronyms! These services are detailed
  18062. in the subsections below.
  18063. @subsubheading Dovecot Service
  18064. @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
  18065. Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
  18066. @end deffn
  18067. By default, Dovecot does not need much configuration; the default
  18068. configuration object created by @code{(dovecot-configuration)} will
  18069. suffice if your mail is delivered to @code{~/Maildir}. A self-signed
  18070. certificate will be generated for TLS-protected connections, though
  18071. Dovecot will also listen on cleartext ports by default. There are a
  18072. number of options, though, which mail administrators might need to change,
  18073. and as is the case with other services, Guix allows the system
  18074. administrator to specify these parameters via a uniform Scheme interface.
  18075. For example, to specify that mail is located at @code{maildir~/.mail},
  18076. one would instantiate the Dovecot service like this:
  18077. @lisp
  18078. (dovecot-service #:config
  18079. (dovecot-configuration
  18080. (mail-location "maildir:~/.mail")))
  18081. @end lisp
  18082. The available configuration parameters follow. Each parameter
  18083. definition is preceded by its type; for example, @samp{string-list foo}
  18084. indicates that the @code{foo} parameter should be specified as a list of
  18085. strings. There is also a way to specify the configuration as a string,
  18086. if you have an old @code{dovecot.conf} file that you want to port over
  18087. from some other system; see the end for more details.
  18088. @c The following documentation was initially generated by
  18089. @c (generate-documentation) in (gnu services mail). Manually maintained
  18090. @c documentation is better, so we shouldn't hesitate to edit below as
  18091. @c needed. However if the change you want to make to this documentation
  18092. @c can be done in an automated way, it's probably easier to change
  18093. @c (generate-documentation) than to make it below and have to deal with
  18094. @c the churn as dovecot updates.
  18095. Available @code{dovecot-configuration} fields are:
  18096. @deftypevr {@code{dovecot-configuration} parameter} package dovecot
  18097. The dovecot package.
  18098. @end deftypevr
  18099. @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
  18100. A list of IPs or hosts where to listen for connections. @samp{*}
  18101. listens on all IPv4 interfaces, @samp{::} listens on all IPv6
  18102. interfaces. If you want to specify non-default ports or anything more
  18103. complex, customize the address and port fields of the
  18104. @samp{inet-listener} of the specific services you are interested in.
  18105. @end deftypevr
  18106. @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
  18107. List of protocols we want to serve. Available protocols include
  18108. @samp{imap}, @samp{pop3}, and @samp{lmtp}.
  18109. Available @code{protocol-configuration} fields are:
  18110. @deftypevr {@code{protocol-configuration} parameter} string name
  18111. The name of the protocol.
  18112. @end deftypevr
  18113. @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
  18114. UNIX socket path to the master authentication server to find users.
  18115. This is used by imap (for shared users) and lda.
  18116. It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
  18117. @end deftypevr
  18118. @deftypevr {@code{protocol-configuration} parameter} boolean imap-metadata?
  18119. Whether to enable the @code{IMAP METADATA} extension as defined in
  18120. @uref{https://tools.ietf.org/html/rfc5464,RFC@tie{}5464}, which provides
  18121. a means for clients to set and retrieve per-mailbox, per-user metadata
  18122. and annotations over IMAP.
  18123. If this is @samp{#t}, you must also specify a dictionary @i{via} the
  18124. @code{mail-attribute-dict} setting.
  18125. Defaults to @samp{#f}.
  18126. @end deftypevr
  18127. @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list managesieve-notify-capabilities
  18128. Which NOTIFY capabilities to report to clients that first connect to
  18129. the ManageSieve service, before authentication. These may differ from the
  18130. capabilities offered to authenticated users. If this field is left empty,
  18131. report what the Sieve interpreter supports by default.
  18132. Defaults to @samp{()}.
  18133. @end deftypevr
  18134. @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list managesieve-sieve-capability
  18135. Which SIEVE capabilities to report to clients that first connect to
  18136. the ManageSieve service, before authentication. These may differ from the
  18137. capabilities offered to authenticated users. If this field is left empty,
  18138. report what the Sieve interpreter supports by default.
  18139. Defaults to @samp{()}.
  18140. @end deftypevr
  18141. @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
  18142. Space separated list of plugins to load.
  18143. @end deftypevr
  18144. @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
  18145. Maximum number of IMAP connections allowed for a user from each IP
  18146. address. NOTE: The username is compared case-sensitively.
  18147. Defaults to @samp{10}.
  18148. @end deftypevr
  18149. @end deftypevr
  18150. @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
  18151. List of services to enable. Available services include @samp{imap},
  18152. @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
  18153. @samp{lmtp}.
  18154. Available @code{service-configuration} fields are:
  18155. @deftypevr {@code{service-configuration} parameter} string kind
  18156. The service kind. Valid values include @code{director},
  18157. @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
  18158. @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
  18159. @code{tcpwrap}, @code{quota-warning}, or anything else.
  18160. @end deftypevr
  18161. @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
  18162. Listeners for the service. A listener is either a
  18163. @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
  18164. an @code{inet-listener-configuration}.
  18165. Defaults to @samp{()}.
  18166. Available @code{unix-listener-configuration} fields are:
  18167. @deftypevr {@code{unix-listener-configuration} parameter} string path
  18168. Path to the file, relative to @code{base-dir} field. This is also used as
  18169. the section name.
  18170. @end deftypevr
  18171. @deftypevr {@code{unix-listener-configuration} parameter} string mode
  18172. The access mode for the socket.
  18173. Defaults to @samp{"0600"}.
  18174. @end deftypevr
  18175. @deftypevr {@code{unix-listener-configuration} parameter} string user
  18176. The user to own the socket.
  18177. Defaults to @samp{""}.
  18178. @end deftypevr
  18179. @deftypevr {@code{unix-listener-configuration} parameter} string group
  18180. The group to own the socket.
  18181. Defaults to @samp{""}.
  18182. @end deftypevr
  18183. Available @code{fifo-listener-configuration} fields are:
  18184. @deftypevr {@code{fifo-listener-configuration} parameter} string path
  18185. Path to the file, relative to @code{base-dir} field. This is also used as
  18186. the section name.
  18187. @end deftypevr
  18188. @deftypevr {@code{fifo-listener-configuration} parameter} string mode
  18189. The access mode for the socket.
  18190. Defaults to @samp{"0600"}.
  18191. @end deftypevr
  18192. @deftypevr {@code{fifo-listener-configuration} parameter} string user
  18193. The user to own the socket.
  18194. Defaults to @samp{""}.
  18195. @end deftypevr
  18196. @deftypevr {@code{fifo-listener-configuration} parameter} string group
  18197. The group to own the socket.
  18198. Defaults to @samp{""}.
  18199. @end deftypevr
  18200. Available @code{inet-listener-configuration} fields are:
  18201. @deftypevr {@code{inet-listener-configuration} parameter} string protocol
  18202. The protocol to listen for.
  18203. @end deftypevr
  18204. @deftypevr {@code{inet-listener-configuration} parameter} string address
  18205. The address on which to listen, or empty for all addresses.
  18206. Defaults to @samp{""}.
  18207. @end deftypevr
  18208. @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
  18209. The port on which to listen.
  18210. @end deftypevr
  18211. @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
  18212. Whether to use SSL for this service; @samp{yes}, @samp{no}, or
  18213. @samp{required}.
  18214. Defaults to @samp{#t}.
  18215. @end deftypevr
  18216. @end deftypevr
  18217. @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
  18218. Maximum number of simultaneous client connections per process. Once
  18219. this number of connections is received, the next incoming connection
  18220. will prompt Dovecot to spawn another process. If set to 0,
  18221. @code{default-client-limit} is used instead.
  18222. Defaults to @samp{0}.
  18223. @end deftypevr
  18224. @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
  18225. Number of connections to handle before starting a new process.
  18226. Typically the only useful values are 0 (unlimited) or 1. 1 is more
  18227. secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
  18228. Defaults to @samp{1}.
  18229. @end deftypevr
  18230. @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
  18231. Maximum number of processes that can exist for this service. If set to
  18232. 0, @code{default-process-limit} is used instead.
  18233. Defaults to @samp{0}.
  18234. @end deftypevr
  18235. @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
  18236. Number of processes to always keep waiting for more connections.
  18237. Defaults to @samp{0}.
  18238. @end deftypevr
  18239. @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
  18240. If you set @samp{service-count 0}, you probably need to grow
  18241. this.
  18242. Defaults to @samp{256000000}.
  18243. @end deftypevr
  18244. @end deftypevr
  18245. @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
  18246. Dict configuration, as created by the @code{dict-configuration}
  18247. constructor.
  18248. Available @code{dict-configuration} fields are:
  18249. @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
  18250. A list of key-value pairs that this dict should hold.
  18251. Defaults to @samp{()}.
  18252. @end deftypevr
  18253. @end deftypevr
  18254. @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
  18255. A list of passdb configurations, each one created by the
  18256. @code{passdb-configuration} constructor.
  18257. Available @code{passdb-configuration} fields are:
  18258. @deftypevr {@code{passdb-configuration} parameter} string driver
  18259. The driver that the passdb should use. Valid values include
  18260. @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
  18261. @samp{static}.
  18262. Defaults to @samp{"pam"}.
  18263. @end deftypevr
  18264. @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
  18265. Space separated list of arguments to the passdb driver.
  18266. Defaults to @samp{""}.
  18267. @end deftypevr
  18268. @end deftypevr
  18269. @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
  18270. List of userdb configurations, each one created by the
  18271. @code{userdb-configuration} constructor.
  18272. Available @code{userdb-configuration} fields are:
  18273. @deftypevr {@code{userdb-configuration} parameter} string driver
  18274. The driver that the userdb should use. Valid values include
  18275. @samp{passwd} and @samp{static}.
  18276. Defaults to @samp{"passwd"}.
  18277. @end deftypevr
  18278. @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
  18279. Space separated list of arguments to the userdb driver.
  18280. Defaults to @samp{""}.
  18281. @end deftypevr
  18282. @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
  18283. Override fields from passwd.
  18284. Defaults to @samp{()}.
  18285. @end deftypevr
  18286. @end deftypevr
  18287. @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
  18288. Plug-in configuration, created by the @code{plugin-configuration}
  18289. constructor.
  18290. @end deftypevr
  18291. @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
  18292. List of namespaces. Each item in the list is created by the
  18293. @code{namespace-configuration} constructor.
  18294. Available @code{namespace-configuration} fields are:
  18295. @deftypevr {@code{namespace-configuration} parameter} string name
  18296. Name for this namespace.
  18297. @end deftypevr
  18298. @deftypevr {@code{namespace-configuration} parameter} string type
  18299. Namespace type: @samp{private}, @samp{shared} or @samp{public}.
  18300. Defaults to @samp{"private"}.
  18301. @end deftypevr
  18302. @deftypevr {@code{namespace-configuration} parameter} string separator
  18303. Hierarchy separator to use. You should use the same separator for
  18304. all namespaces or some clients get confused. @samp{/} is usually a good
  18305. one. The default however depends on the underlying mail storage
  18306. format.
  18307. Defaults to @samp{""}.
  18308. @end deftypevr
  18309. @deftypevr {@code{namespace-configuration} parameter} string prefix
  18310. Prefix required to access this namespace. This needs to be
  18311. different for all namespaces. For example @samp{Public/}.
  18312. Defaults to @samp{""}.
  18313. @end deftypevr
  18314. @deftypevr {@code{namespace-configuration} parameter} string location
  18315. Physical location of the mailbox. This is in the same format as
  18316. mail_location, which is also the default for it.
  18317. Defaults to @samp{""}.
  18318. @end deftypevr
  18319. @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
  18320. There can be only one INBOX, and this setting defines which
  18321. namespace has it.
  18322. Defaults to @samp{#f}.
  18323. @end deftypevr
  18324. @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
  18325. If namespace is hidden, it's not advertised to clients via NAMESPACE
  18326. extension. You'll most likely also want to set @samp{list? #f}. This is mostly
  18327. useful when converting from another server with different namespaces
  18328. which you want to deprecate but still keep working. For example you can
  18329. create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
  18330. and @samp{mail/}.
  18331. Defaults to @samp{#f}.
  18332. @end deftypevr
  18333. @deftypevr {@code{namespace-configuration} parameter} boolean list?
  18334. Show the mailboxes under this namespace with the LIST command. This
  18335. makes the namespace visible for clients that do not support the NAMESPACE
  18336. extension. The special @code{children} value lists child mailboxes, but
  18337. hides the namespace prefix.
  18338. Defaults to @samp{#t}.
  18339. @end deftypevr
  18340. @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
  18341. Namespace handles its own subscriptions. If set to @code{#f}, the
  18342. parent namespace handles them. The empty prefix should always have this
  18343. as @code{#t}).
  18344. Defaults to @samp{#t}.
  18345. @end deftypevr
  18346. @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
  18347. List of predefined mailboxes in this namespace.
  18348. Defaults to @samp{()}.
  18349. Available @code{mailbox-configuration} fields are:
  18350. @deftypevr {@code{mailbox-configuration} parameter} string name
  18351. Name for this mailbox.
  18352. @end deftypevr
  18353. @deftypevr {@code{mailbox-configuration} parameter} string auto
  18354. @samp{create} will automatically create this mailbox.
  18355. @samp{subscribe} will both create and subscribe to the mailbox.
  18356. Defaults to @samp{"no"}.
  18357. @end deftypevr
  18358. @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
  18359. List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
  18360. Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
  18361. @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
  18362. Defaults to @samp{()}.
  18363. @end deftypevr
  18364. @end deftypevr
  18365. @end deftypevr
  18366. @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
  18367. Base directory where to store runtime data.
  18368. Defaults to @samp{"/var/run/dovecot/"}.
  18369. @end deftypevr
  18370. @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
  18371. Greeting message for clients.
  18372. Defaults to @samp{"Dovecot ready."}.
  18373. @end deftypevr
  18374. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
  18375. List of trusted network ranges. Connections from these IPs are
  18376. allowed to override their IP addresses and ports (for logging and for
  18377. authentication checks). @samp{disable-plaintext-auth} is also ignored
  18378. for these networks. Typically you would specify your IMAP proxy servers
  18379. here.
  18380. Defaults to @samp{()}.
  18381. @end deftypevr
  18382. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
  18383. List of login access check sockets (e.g.@: tcpwrap).
  18384. Defaults to @samp{()}.
  18385. @end deftypevr
  18386. @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
  18387. Show more verbose process titles (in ps). Currently shows user name
  18388. and IP address. Useful for seeing who is actually using the IMAP
  18389. processes (e.g.@: shared mailboxes or if the same uid is used for multiple
  18390. accounts).
  18391. Defaults to @samp{#f}.
  18392. @end deftypevr
  18393. @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
  18394. Should all processes be killed when Dovecot master process shuts down.
  18395. Setting this to @code{#f} means that Dovecot can be upgraded without
  18396. forcing existing client connections to close (although that could also
  18397. be a problem if the upgrade is e.g.@: due to a security fix).
  18398. Defaults to @samp{#t}.
  18399. @end deftypevr
  18400. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
  18401. If non-zero, run mail commands via this many connections to doveadm
  18402. server, instead of running them directly in the same process.
  18403. Defaults to @samp{0}.
  18404. @end deftypevr
  18405. @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
  18406. UNIX socket or host:port used for connecting to doveadm server.
  18407. Defaults to @samp{"doveadm-server"}.
  18408. @end deftypevr
  18409. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
  18410. List of environment variables that are preserved on Dovecot startup
  18411. and passed down to all of its child processes. You can also give
  18412. key=value pairs to always set specific settings.
  18413. @end deftypevr
  18414. @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
  18415. Disable LOGIN command and all other plaintext authentications unless
  18416. SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
  18417. matches the local IP (i.e.@: you're connecting from the same computer),
  18418. the connection is considered secure and plaintext authentication is
  18419. allowed. See also ssl=required setting.
  18420. Defaults to @samp{#t}.
  18421. @end deftypevr
  18422. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
  18423. Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
  18424. Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
  18425. for caching to be used.
  18426. Defaults to @samp{0}.
  18427. @end deftypevr
  18428. @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
  18429. Time to live for cached data. After TTL expires the cached record
  18430. is no longer used, *except* if the main database lookup returns internal
  18431. failure. We also try to handle password changes automatically: If
  18432. user's previous authentication was successful, but this one wasn't, the
  18433. cache isn't used. For now this works only with plaintext
  18434. authentication.
  18435. Defaults to @samp{"1 hour"}.
  18436. @end deftypevr
  18437. @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
  18438. TTL for negative hits (user not found, password mismatch).
  18439. 0 disables caching them completely.
  18440. Defaults to @samp{"1 hour"}.
  18441. @end deftypevr
  18442. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
  18443. List of realms for SASL authentication mechanisms that need them.
  18444. You can leave it empty if you don't want to support multiple realms.
  18445. Many clients simply use the first one listed here, so keep the default
  18446. realm first.
  18447. Defaults to @samp{()}.
  18448. @end deftypevr
  18449. @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
  18450. Default realm/domain to use if none was specified. This is used for
  18451. both SASL realms and appending @@domain to username in plaintext
  18452. logins.
  18453. Defaults to @samp{""}.
  18454. @end deftypevr
  18455. @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
  18456. List of allowed characters in username. If the user-given username
  18457. contains a character not listed in here, the login automatically fails.
  18458. This is just an extra check to make sure user can't exploit any
  18459. potential quote escaping vulnerabilities with SQL/LDAP databases. If
  18460. you want to allow all characters, set this value to empty.
  18461. Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
  18462. @end deftypevr
  18463. @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
  18464. Username character translations before it's looked up from
  18465. databases. The value contains series of from -> to characters. For
  18466. example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
  18467. translated to @samp{@@}.
  18468. Defaults to @samp{""}.
  18469. @end deftypevr
  18470. @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
  18471. Username formatting before it's looked up from databases. You can
  18472. use the standard variables here, e.g.@: %Lu would lowercase the username,
  18473. %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
  18474. change the @samp{@@} into @samp{-AT-}. This translation is done after
  18475. @samp{auth-username-translation} changes.
  18476. Defaults to @samp{"%Lu"}.
  18477. @end deftypevr
  18478. @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
  18479. If you want to allow master users to log in by specifying the master
  18480. username within the normal username string (i.e.@: not using SASL
  18481. mechanism's support for it), you can specify the separator character
  18482. here. The format is then <username><separator><master username>.
  18483. UW-IMAP uses @samp{*} as the separator, so that could be a good
  18484. choice.
  18485. Defaults to @samp{""}.
  18486. @end deftypevr
  18487. @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
  18488. Username to use for users logging in with ANONYMOUS SASL
  18489. mechanism.
  18490. Defaults to @samp{"anonymous"}.
  18491. @end deftypevr
  18492. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
  18493. Maximum number of dovecot-auth worker processes. They're used to
  18494. execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
  18495. They're automatically created and destroyed as needed.
  18496. Defaults to @samp{30}.
  18497. @end deftypevr
  18498. @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
  18499. Host name to use in GSSAPI principal names. The default is to use
  18500. the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
  18501. allow all keytab entries.
  18502. Defaults to @samp{""}.
  18503. @end deftypevr
  18504. @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
  18505. Kerberos keytab to use for the GSSAPI mechanism. Will use the
  18506. system default (usually @file{/etc/krb5.keytab}) if not specified. You may
  18507. need to change the auth service to run as root to be able to read this
  18508. file.
  18509. Defaults to @samp{""}.
  18510. @end deftypevr
  18511. @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
  18512. Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
  18513. and @samp{ntlm-auth} helper.
  18514. <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
  18515. Defaults to @samp{#f}.
  18516. @end deftypevr
  18517. @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
  18518. Path for Samba's @samp{ntlm-auth} helper binary.
  18519. Defaults to @samp{"/usr/bin/ntlm_auth"}.
  18520. @end deftypevr
  18521. @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
  18522. Time to delay before replying to failed authentications.
  18523. Defaults to @samp{"2 secs"}.
  18524. @end deftypevr
  18525. @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
  18526. Require a valid SSL client certificate or the authentication
  18527. fails.
  18528. Defaults to @samp{#f}.
  18529. @end deftypevr
  18530. @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
  18531. Take the username from client's SSL certificate, using
  18532. @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
  18533. CommonName.
  18534. Defaults to @samp{#f}.
  18535. @end deftypevr
  18536. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
  18537. List of wanted authentication mechanisms. Supported mechanisms are:
  18538. @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
  18539. @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
  18540. @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
  18541. @samp{disable-plaintext-auth} setting.
  18542. @end deftypevr
  18543. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
  18544. List of IPs or hostnames to all director servers, including ourself.
  18545. Ports can be specified as ip:port. The default port is the same as what
  18546. director service's @samp{inet-listener} is using.
  18547. Defaults to @samp{()}.
  18548. @end deftypevr
  18549. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
  18550. List of IPs or hostnames to all backend mail servers. Ranges are
  18551. allowed too, like 10.0.0.10-10.0.0.30.
  18552. Defaults to @samp{()}.
  18553. @end deftypevr
  18554. @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
  18555. How long to redirect users to a specific server after it no longer
  18556. has any connections.
  18557. Defaults to @samp{"15 min"}.
  18558. @end deftypevr
  18559. @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
  18560. How the username is translated before being hashed. Useful values
  18561. include %Ln if user can log in with or without @@domain, %Ld if mailboxes
  18562. are shared within domain.
  18563. Defaults to @samp{"%Lu"}.
  18564. @end deftypevr
  18565. @deftypevr {@code{dovecot-configuration} parameter} string log-path
  18566. Log file to use for error messages. @samp{syslog} logs to syslog,
  18567. @samp{/dev/stderr} logs to stderr.
  18568. Defaults to @samp{"syslog"}.
  18569. @end deftypevr
  18570. @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
  18571. Log file to use for informational messages. Defaults to
  18572. @samp{log-path}.
  18573. Defaults to @samp{""}.
  18574. @end deftypevr
  18575. @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
  18576. Log file to use for debug messages. Defaults to
  18577. @samp{info-log-path}.
  18578. Defaults to @samp{""}.
  18579. @end deftypevr
  18580. @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
  18581. Syslog facility to use if you're logging to syslog. Usually if you
  18582. don't want to use @samp{mail}, you'll use local0..local7. Also other
  18583. standard facilities are supported.
  18584. Defaults to @samp{"mail"}.
  18585. @end deftypevr
  18586. @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
  18587. Log unsuccessful authentication attempts and the reasons why they
  18588. failed.
  18589. Defaults to @samp{#f}.
  18590. @end deftypevr
  18591. @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
  18592. In case of password mismatches, log the attempted password. Valid
  18593. values are no, plain and sha1. sha1 can be useful for detecting brute
  18594. force password attempts vs. user simply trying the same password over
  18595. and over again. You can also truncate the value to n chars by appending
  18596. ":n" (e.g.@: sha1:6).
  18597. Defaults to @samp{"no"}.
  18598. @end deftypevr
  18599. @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
  18600. Even more verbose logging for debugging purposes. Shows for example
  18601. SQL queries.
  18602. Defaults to @samp{#f}.
  18603. @end deftypevr
  18604. @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
  18605. In case of password mismatches, log the passwords and used scheme so
  18606. the problem can be debugged. Enabling this also enables
  18607. @samp{auth-debug}.
  18608. Defaults to @samp{#f}.
  18609. @end deftypevr
  18610. @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
  18611. Enable mail process debugging. This can help you figure out why
  18612. Dovecot isn't finding your mails.
  18613. Defaults to @samp{#f}.
  18614. @end deftypevr
  18615. @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
  18616. Show protocol level SSL errors.
  18617. Defaults to @samp{#f}.
  18618. @end deftypevr
  18619. @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
  18620. Prefix for each line written to log file. % codes are in
  18621. strftime(3) format.
  18622. Defaults to @samp{"\"%b %d %H:%M:%S \""}.
  18623. @end deftypevr
  18624. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
  18625. List of elements we want to log. The elements which have a
  18626. non-empty variable value are joined together to form a comma-separated
  18627. string.
  18628. @end deftypevr
  18629. @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
  18630. Login log format. %s contains @samp{login-log-format-elements}
  18631. string, %$ contains the data we want to log.
  18632. Defaults to @samp{"%$: %s"}.
  18633. @end deftypevr
  18634. @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
  18635. Log prefix for mail processes. See doc/wiki/Variables.txt for list
  18636. of possible variables you can use.
  18637. Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
  18638. @end deftypevr
  18639. @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
  18640. Format to use for logging mail deliveries. You can use variables:
  18641. @table @code
  18642. @item %$
  18643. Delivery status message (e.g.@: @samp{saved to INBOX})
  18644. @item %m
  18645. Message-ID
  18646. @item %s
  18647. Subject
  18648. @item %f
  18649. From address
  18650. @item %p
  18651. Physical size
  18652. @item %w
  18653. Virtual size.
  18654. @end table
  18655. Defaults to @samp{"msgid=%m: %$"}.
  18656. @end deftypevr
  18657. @deftypevr {@code{dovecot-configuration} parameter} string mail-location
  18658. Location for users' mailboxes. The default is empty, which means
  18659. that Dovecot tries to find the mailboxes automatically. This won't work
  18660. if the user doesn't yet have any mail, so you should explicitly tell
  18661. Dovecot the full location.
  18662. If you're using mbox, giving a path to the INBOX
  18663. file (e.g.@: @file{/var/mail/%u}) isn't enough. You'll also need to tell Dovecot
  18664. where the other mailboxes are kept. This is called the @emph{root mail
  18665. directory}, and it must be the first path given in the
  18666. @samp{mail-location} setting.
  18667. There are a few special variables you can use, e.g.:
  18668. @table @samp
  18669. @item %u
  18670. username
  18671. @item %n
  18672. user part in user@@domain, same as %u if there's no domain
  18673. @item %d
  18674. domain part in user@@domain, empty if there's no domain
  18675. @item %h
  18676. home director
  18677. @end table
  18678. See doc/wiki/Variables.txt for full list. Some examples:
  18679. @table @samp
  18680. @item maildir:~/Maildir
  18681. @item mbox:~/mail:INBOX=/var/mail/%u
  18682. @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
  18683. @end table
  18684. Defaults to @samp{""}.
  18685. @end deftypevr
  18686. @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
  18687. System user and group used to access mails. If you use multiple,
  18688. userdb can override these by returning uid or gid fields. You can use
  18689. either numbers or names. <doc/wiki/UserIds.txt>.
  18690. Defaults to @samp{""}.
  18691. @end deftypevr
  18692. @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
  18693. Defaults to @samp{""}.
  18694. @end deftypevr
  18695. @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
  18696. Group to enable temporarily for privileged operations. Currently
  18697. this is used only with INBOX when either its initial creation or
  18698. dotlocking fails. Typically this is set to @samp{"mail"} to give access to
  18699. @file{/var/mail}.
  18700. Defaults to @samp{""}.
  18701. @end deftypevr
  18702. @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
  18703. Grant access to these supplementary groups for mail processes.
  18704. Typically these are used to set up access to shared mailboxes. Note
  18705. that it may be dangerous to set these if users can create symlinks
  18706. (e.g.@: if @samp{mail} group is set here, @code{ln -s /var/mail ~/mail/var}
  18707. could allow a user to delete others' mailboxes, or @code{ln -s
  18708. /secret/shared/box ~/mail/mybox} would allow reading it). Defaults to
  18709. @samp{""}.
  18710. @end deftypevr
  18711. @deftypevr {@code{dovecot-configuration} parameter} string mail-attribute-dict
  18712. The location of a dictionary used to store @code{IMAP METADATA}
  18713. as defined by @uref{https://tools.ietf.org/html/rfc5464, RFC@tie{}5464}.
  18714. The IMAP METADATA commands are available only if the ``imap''
  18715. protocol configuration's @code{imap-metadata?} field is @samp{#t}.
  18716. Defaults to @samp{""}.
  18717. @end deftypevr
  18718. @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
  18719. Allow full file system access to clients. There's no access checks
  18720. other than what the operating system does for the active UID/GID@. It
  18721. works with both maildir and mboxes, allowing you to prefix mailboxes
  18722. names with e.g.@: @file{/path/} or @file{~user/}.
  18723. Defaults to @samp{#f}.
  18724. @end deftypevr
  18725. @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
  18726. Don't use @code{mmap()} at all. This is required if you store indexes to
  18727. shared file systems (NFS or clustered file system).
  18728. Defaults to @samp{#f}.
  18729. @end deftypevr
  18730. @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
  18731. Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
  18732. supports @samp{O_EXCL} since version 3, so this should be safe to use
  18733. nowadays by default.
  18734. Defaults to @samp{#t}.
  18735. @end deftypevr
  18736. @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
  18737. When to use fsync() or fdatasync() calls:
  18738. @table @code
  18739. @item optimized
  18740. Whenever necessary to avoid losing important data
  18741. @item always
  18742. Useful with e.g.@: NFS when @code{write()}s are delayed
  18743. @item never
  18744. Never use it (best performance, but crashes can lose data).
  18745. @end table
  18746. Defaults to @samp{"optimized"}.
  18747. @end deftypevr
  18748. @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
  18749. Mail storage exists in NFS@. Set this to yes to make Dovecot flush
  18750. NFS caches whenever needed. If you're using only a single mail server
  18751. this isn't needed.
  18752. Defaults to @samp{#f}.
  18753. @end deftypevr
  18754. @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
  18755. Mail index files also exist in NFS@. Setting this to yes requires
  18756. @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
  18757. Defaults to @samp{#f}.
  18758. @end deftypevr
  18759. @deftypevr {@code{dovecot-configuration} parameter} string lock-method
  18760. Locking method for index files. Alternatives are fcntl, flock and
  18761. dotlock. Dotlocking uses some tricks which may create more disk I/O
  18762. than other locking methods. NFS users: flock doesn't work, remember to
  18763. change @samp{mmap-disable}.
  18764. Defaults to @samp{"fcntl"}.
  18765. @end deftypevr
  18766. @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
  18767. Directory in which LDA/LMTP temporarily stores incoming mails >128
  18768. kB.
  18769. Defaults to @samp{"/tmp"}.
  18770. @end deftypevr
  18771. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
  18772. Valid UID range for users. This is mostly to make sure that users can't
  18773. log in as daemons or other system users. Note that denying root logins is
  18774. hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
  18775. is set to 0.
  18776. Defaults to @samp{500}.
  18777. @end deftypevr
  18778. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
  18779. Defaults to @samp{0}.
  18780. @end deftypevr
  18781. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
  18782. Valid GID range for users. Users having non-valid GID as primary group ID
  18783. aren't allowed to log in. If user belongs to supplementary groups with
  18784. non-valid GIDs, those groups are not set.
  18785. Defaults to @samp{1}.
  18786. @end deftypevr
  18787. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
  18788. Defaults to @samp{0}.
  18789. @end deftypevr
  18790. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
  18791. Maximum allowed length for mail keyword name. It's only forced when
  18792. trying to create new keywords.
  18793. Defaults to @samp{50}.
  18794. @end deftypevr
  18795. @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
  18796. List of directories under which chrooting is allowed for mail
  18797. processes (i.e.@: @file{/var/mail} will allow chrooting to @file{/var/mail/foo/bar}
  18798. too). This setting doesn't affect @samp{login-chroot}
  18799. @samp{mail-chroot} or auth chroot settings. If this setting is empty,
  18800. @samp{/./} in home dirs are ignored. WARNING: Never add directories here
  18801. which local users can modify, that may lead to root exploit. Usually
  18802. this should be done only if you don't allow shell access for users.
  18803. <doc/wiki/Chrooting.txt>.
  18804. Defaults to @samp{()}.
  18805. @end deftypevr
  18806. @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
  18807. Default chroot directory for mail processes. This can be overridden
  18808. for specific users in user database by giving @samp{/./} in user's home
  18809. directory (e.g.@: @samp{/home/./user} chroots into @file{/home}). Note that usually
  18810. there is no real need to do chrooting, Dovecot doesn't allow users to
  18811. access files outside their mail directory anyway. If your home
  18812. directories are prefixed with the chroot directory, append @samp{/.} to
  18813. @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
  18814. Defaults to @samp{""}.
  18815. @end deftypevr
  18816. @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
  18817. UNIX socket path to master authentication server to find users.
  18818. This is used by imap (for shared users) and lda.
  18819. Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
  18820. @end deftypevr
  18821. @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
  18822. Directory where to look up mail plugins.
  18823. Defaults to @samp{"/usr/lib/dovecot"}.
  18824. @end deftypevr
  18825. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
  18826. List of plugins to load for all services. Plugins specific to IMAP,
  18827. LDA, etc.@: are added to this list in their own .conf files.
  18828. Defaults to @samp{()}.
  18829. @end deftypevr
  18830. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
  18831. The minimum number of mails in a mailbox before updates are done to
  18832. cache file. This allows optimizing Dovecot's behavior to do less disk
  18833. writes at the cost of more disk reads.
  18834. Defaults to @samp{0}.
  18835. @end deftypevr
  18836. @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
  18837. When IDLE command is running, mailbox is checked once in a while to
  18838. see if there are any new mails or other changes. This setting defines
  18839. the minimum time to wait between those checks. Dovecot can also use
  18840. dnotify, inotify and kqueue to find out immediately when changes
  18841. occur.
  18842. Defaults to @samp{"30 secs"}.
  18843. @end deftypevr
  18844. @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
  18845. Save mails with CR+LF instead of plain LF@. This makes sending those
  18846. mails take less CPU, especially with sendfile() syscall with Linux and
  18847. FreeBSD@. But it also creates a bit more disk I/O which may just make it
  18848. slower. Also note that if other software reads the mboxes/maildirs,
  18849. they may handle the extra CRs wrong and cause problems.
  18850. Defaults to @samp{#f}.
  18851. @end deftypevr
  18852. @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
  18853. By default LIST command returns all entries in maildir beginning
  18854. with a dot. Enabling this option makes Dovecot return only entries
  18855. which are directories. This is done by stat()ing each entry, so it
  18856. causes more disk I/O.
  18857. (For systems setting struct @samp{dirent->d_type} this check is free
  18858. and it's done always regardless of this setting).
  18859. Defaults to @samp{#f}.
  18860. @end deftypevr
  18861. @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
  18862. When copying a message, do it with hard links whenever possible.
  18863. This makes the performance much better, and it's unlikely to have any
  18864. side effects.
  18865. Defaults to @samp{#t}.
  18866. @end deftypevr
  18867. @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
  18868. Assume Dovecot is the only MUA accessing Maildir: Scan cur/
  18869. directory only when its mtime changes unexpectedly or when we can't find
  18870. the mail otherwise.
  18871. Defaults to @samp{#f}.
  18872. @end deftypevr
  18873. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
  18874. Which locking methods to use for locking mbox. There are four
  18875. available:
  18876. @table @code
  18877. @item dotlock
  18878. Create <mailbox>.lock file. This is the oldest and most NFS-safe
  18879. solution. If you want to use /var/mail/ like directory, the users will
  18880. need write access to that directory.
  18881. @item dotlock-try
  18882. Same as dotlock, but if it fails because of permissions or because there
  18883. isn't enough disk space, just skip it.
  18884. @item fcntl
  18885. Use this if possible. Works with NFS too if lockd is used.
  18886. @item flock
  18887. May not exist in all systems. Doesn't work with NFS.
  18888. @item lockf
  18889. May not exist in all systems. Doesn't work with NFS.
  18890. @end table
  18891. You can use multiple locking methods; if you do the order they're declared
  18892. in is important to avoid deadlocks if other MTAs/MUAs are using multiple
  18893. locking methods as well. Some operating systems don't allow using some of
  18894. them simultaneously.
  18895. @end deftypevr
  18896. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
  18897. @end deftypevr
  18898. @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
  18899. Maximum time to wait for lock (all of them) before aborting.
  18900. Defaults to @samp{"5 mins"}.
  18901. @end deftypevr
  18902. @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
  18903. If dotlock exists but the mailbox isn't modified in any way,
  18904. override the lock file after this much time.
  18905. Defaults to @samp{"2 mins"}.
  18906. @end deftypevr
  18907. @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
  18908. When mbox changes unexpectedly we have to fully read it to find out
  18909. what changed. If the mbox is large this can take a long time. Since
  18910. the change is usually just a newly appended mail, it'd be faster to
  18911. simply read the new mails. If this setting is enabled, Dovecot does
  18912. this but still safely fallbacks to re-reading the whole mbox file
  18913. whenever something in mbox isn't how it's expected to be. The only real
  18914. downside to this setting is that if some other MUA changes message
  18915. flags, Dovecot doesn't notice it immediately. Note that a full sync is
  18916. done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
  18917. Defaults to @samp{#t}.
  18918. @end deftypevr
  18919. @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
  18920. Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
  18921. EXAMINE, EXPUNGE or CHECK commands. If this is set,
  18922. @samp{mbox-dirty-syncs} is ignored.
  18923. Defaults to @samp{#f}.
  18924. @end deftypevr
  18925. @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
  18926. Delay writing mbox headers until doing a full write sync (EXPUNGE
  18927. and CHECK commands and when closing the mailbox). This is especially
  18928. useful for POP3 where clients often delete all mails. The downside is
  18929. that our changes aren't immediately visible to other MUAs.
  18930. Defaults to @samp{#t}.
  18931. @end deftypevr
  18932. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
  18933. If mbox size is smaller than this (e.g.@: 100k), don't write index
  18934. files. If an index file already exists it's still read, just not
  18935. updated.
  18936. Defaults to @samp{0}.
  18937. @end deftypevr
  18938. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
  18939. Maximum dbox file size until it's rotated.
  18940. Defaults to @samp{10000000}.
  18941. @end deftypevr
  18942. @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
  18943. Maximum dbox file age until it's rotated. Typically in days. Day
  18944. begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
  18945. disabled.
  18946. Defaults to @samp{"1d"}.
  18947. @end deftypevr
  18948. @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
  18949. When creating new mdbox files, immediately preallocate their size to
  18950. @samp{mdbox-rotate-size}. This setting currently works only in Linux
  18951. with some file systems (ext4, xfs).
  18952. Defaults to @samp{#f}.
  18953. @end deftypevr
  18954. @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
  18955. sdbox and mdbox support saving mail attachments to external files,
  18956. which also allows single instance storage for them. Other backends
  18957. don't support this for now.
  18958. WARNING: This feature hasn't been tested much yet. Use at your own risk.
  18959. Directory root where to store mail attachments. Disabled, if empty.
  18960. Defaults to @samp{""}.
  18961. @end deftypevr
  18962. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
  18963. Attachments smaller than this aren't saved externally. It's also
  18964. possible to write a plugin to disable saving specific attachments
  18965. externally.
  18966. Defaults to @samp{128000}.
  18967. @end deftypevr
  18968. @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
  18969. File system backend to use for saving attachments:
  18970. @table @code
  18971. @item posix
  18972. No SiS done by Dovecot (but this might help FS's own deduplication)
  18973. @item sis posix
  18974. SiS with immediate byte-by-byte comparison during saving
  18975. @item sis-queue posix
  18976. SiS with delayed comparison and deduplication.
  18977. @end table
  18978. Defaults to @samp{"sis posix"}.
  18979. @end deftypevr
  18980. @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
  18981. Hash format to use in attachment filenames. You can add any text and
  18982. variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
  18983. @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
  18984. truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
  18985. Defaults to @samp{"%@{sha1@}"}.
  18986. @end deftypevr
  18987. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
  18988. Defaults to @samp{100}.
  18989. @end deftypevr
  18990. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
  18991. Defaults to @samp{1000}.
  18992. @end deftypevr
  18993. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
  18994. Default VSZ (virtual memory size) limit for service processes.
  18995. This is mainly intended to catch and kill processes that leak memory
  18996. before they eat up everything.
  18997. Defaults to @samp{256000000}.
  18998. @end deftypevr
  18999. @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
  19000. Login user is internally used by login processes. This is the most
  19001. untrusted user in Dovecot system. It shouldn't have access to anything
  19002. at all.
  19003. Defaults to @samp{"dovenull"}.
  19004. @end deftypevr
  19005. @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
  19006. Internal user is used by unprivileged processes. It should be
  19007. separate from login user, so that login processes can't disturb other
  19008. processes.
  19009. Defaults to @samp{"dovecot"}.
  19010. @end deftypevr
  19011. @deftypevr {@code{dovecot-configuration} parameter} string ssl?
  19012. SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
  19013. Defaults to @samp{"required"}.
  19014. @end deftypevr
  19015. @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
  19016. PEM encoded X.509 SSL/TLS certificate (public key).
  19017. Defaults to @samp{"</etc/dovecot/default.pem"}.
  19018. @end deftypevr
  19019. @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
  19020. PEM encoded SSL/TLS private key. The key is opened before
  19021. dropping root privileges, so keep the key file unreadable by anyone but
  19022. root.
  19023. Defaults to @samp{"</etc/dovecot/private/default.pem"}.
  19024. @end deftypevr
  19025. @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
  19026. If key file is password protected, give the password here.
  19027. Alternatively give it when starting dovecot with -p parameter. Since
  19028. this file is often world-readable, you may want to place this setting
  19029. instead to a different.
  19030. Defaults to @samp{""}.
  19031. @end deftypevr
  19032. @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
  19033. PEM encoded trusted certificate authority. Set this only if you
  19034. intend to use @samp{ssl-verify-client-cert? #t}. The file should
  19035. contain the CA certificate(s) followed by the matching
  19036. CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
  19037. Defaults to @samp{""}.
  19038. @end deftypevr
  19039. @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
  19040. Require that CRL check succeeds for client certificates.
  19041. Defaults to @samp{#t}.
  19042. @end deftypevr
  19043. @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
  19044. Request client to send a certificate. If you also want to require
  19045. it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
  19046. Defaults to @samp{#f}.
  19047. @end deftypevr
  19048. @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
  19049. Which field from certificate to use for username. commonName and
  19050. x500UniqueIdentifier are the usual choices. You'll also need to set
  19051. @samp{auth-ssl-username-from-cert? #t}.
  19052. Defaults to @samp{"commonName"}.
  19053. @end deftypevr
  19054. @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
  19055. Minimum SSL protocol version to accept.
  19056. Defaults to @samp{"TLSv1"}.
  19057. @end deftypevr
  19058. @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
  19059. SSL ciphers to use.
  19060. Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
  19061. @end deftypevr
  19062. @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
  19063. SSL crypto device to use, for valid values run "openssl engine".
  19064. Defaults to @samp{""}.
  19065. @end deftypevr
  19066. @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
  19067. Address to use when sending rejection mails.
  19068. %d expands to recipient domain.
  19069. Defaults to @samp{"postmaster@@%d"}.
  19070. @end deftypevr
  19071. @deftypevr {@code{dovecot-configuration} parameter} string hostname
  19072. Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
  19073. and in LMTP replies. Default is the system's real hostname@@domain.
  19074. Defaults to @samp{""}.
  19075. @end deftypevr
  19076. @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
  19077. If user is over quota, return with temporary failure instead of
  19078. bouncing the mail.
  19079. Defaults to @samp{#f}.
  19080. @end deftypevr
  19081. @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
  19082. Binary to use for sending mails.
  19083. Defaults to @samp{"/usr/sbin/sendmail"}.
  19084. @end deftypevr
  19085. @deftypevr {@code{dovecot-configuration} parameter} string submission-host
  19086. If non-empty, send mails via this SMTP host[:port] instead of
  19087. sendmail.
  19088. Defaults to @samp{""}.
  19089. @end deftypevr
  19090. @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
  19091. Subject: header to use for rejection mails. You can use the same
  19092. variables as for @samp{rejection-reason} below.
  19093. Defaults to @samp{"Rejected: %s"}.
  19094. @end deftypevr
  19095. @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
  19096. Human readable error message for rejection mails. You can use
  19097. variables:
  19098. @table @code
  19099. @item %n
  19100. CRLF
  19101. @item %r
  19102. reason
  19103. @item %s
  19104. original subject
  19105. @item %t
  19106. recipient
  19107. @end table
  19108. Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
  19109. @end deftypevr
  19110. @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
  19111. Delimiter character between local-part and detail in email
  19112. address.
  19113. Defaults to @samp{"+"}.
  19114. @end deftypevr
  19115. @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
  19116. Header where the original recipient address (SMTP's RCPT TO:
  19117. address) is taken from if not available elsewhere. With dovecot-lda -a
  19118. parameter overrides this. A commonly used header for this is
  19119. X-Original-To.
  19120. Defaults to @samp{""}.
  19121. @end deftypevr
  19122. @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
  19123. Should saving a mail to a nonexistent mailbox automatically create
  19124. it?.
  19125. Defaults to @samp{#f}.
  19126. @end deftypevr
  19127. @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
  19128. Should automatically created mailboxes be also automatically
  19129. subscribed?.
  19130. Defaults to @samp{#f}.
  19131. @end deftypevr
  19132. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
  19133. Maximum IMAP command line length. Some clients generate very long
  19134. command lines with huge mailboxes, so you may need to raise this if you
  19135. get "Too long argument" or "IMAP command line too large" errors
  19136. often.
  19137. Defaults to @samp{64000}.
  19138. @end deftypevr
  19139. @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
  19140. IMAP logout format string:
  19141. @table @code
  19142. @item %i
  19143. total number of bytes read from client
  19144. @item %o
  19145. total number of bytes sent to client.
  19146. @end table
  19147. See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
  19148. Defaults to @samp{"in=%i out=%o deleted=%@{deleted@} expunged=%@{expunged@} trashed=%@{trashed@} hdr_count=%@{fetch_hdr_count@} hdr_bytes=%@{fetch_hdr_bytes@} body_count=%@{fetch_body_count@} body_bytes=%@{fetch_body_bytes@}"}.
  19149. @end deftypevr
  19150. @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
  19151. Override the IMAP CAPABILITY response. If the value begins with '+',
  19152. add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
  19153. Defaults to @samp{""}.
  19154. @end deftypevr
  19155. @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
  19156. How long to wait between "OK Still here" notifications when client
  19157. is IDLEing.
  19158. Defaults to @samp{"2 mins"}.
  19159. @end deftypevr
  19160. @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
  19161. ID field names and values to send to clients. Using * as the value
  19162. makes Dovecot use the default value. The following fields have default
  19163. values currently: name, version, os, os-version, support-url,
  19164. support-email.
  19165. Defaults to @samp{""}.
  19166. @end deftypevr
  19167. @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
  19168. ID fields sent by client to log. * means everything.
  19169. Defaults to @samp{""}.
  19170. @end deftypevr
  19171. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
  19172. Workarounds for various client bugs:
  19173. @table @code
  19174. @item delay-newmail
  19175. Send EXISTS/RECENT new mail notifications only when replying to NOOP and
  19176. CHECK commands. Some clients ignore them otherwise, for example OSX
  19177. Mail (<v2.1). Outlook Express breaks more badly though, without this it
  19178. may show user "Message no longer in server" errors. Note that OE6
  19179. still breaks even with this workaround if synchronization is set to
  19180. "Headers Only".
  19181. @item tb-extra-mailbox-sep
  19182. Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
  19183. adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
  19184. ignore the extra @samp{/} instead of treating it as invalid mailbox name.
  19185. @item tb-lsub-flags
  19186. Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
  19187. This makes Thunderbird realize they aren't selectable and show them
  19188. greyed out, instead of only later giving "not selectable" popup error.
  19189. @end table
  19190. Defaults to @samp{()}.
  19191. @end deftypevr
  19192. @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
  19193. Host allowed in URLAUTH URLs sent by client. "*" allows all.
  19194. Defaults to @samp{""}.
  19195. @end deftypevr
  19196. Whew! Lots of configuration options. The nice thing about it though is
  19197. that Guix has a complete interface to Dovecot's configuration
  19198. language. This allows not only a nice way to declare configurations,
  19199. but also offers reflective capabilities as well: users can write code to
  19200. inspect and transform configurations from within Scheme.
  19201. However, it could be that you just want to get a @code{dovecot.conf} up
  19202. and running. In that case, you can pass an
  19203. @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
  19204. @code{dovecot-service}. As its name indicates, an opaque configuration
  19205. does not have easy reflective capabilities.
  19206. Available @code{opaque-dovecot-configuration} fields are:
  19207. @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
  19208. The dovecot package.
  19209. @end deftypevr
  19210. @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
  19211. The contents of the @code{dovecot.conf}, as a string.
  19212. @end deftypevr
  19213. For example, if your @code{dovecot.conf} is just the empty string, you
  19214. could instantiate a dovecot service like this:
  19215. @lisp
  19216. (dovecot-service #:config
  19217. (opaque-dovecot-configuration
  19218. (string "")))
  19219. @end lisp
  19220. @subsubheading OpenSMTPD Service
  19221. @deffn {Scheme Variable} opensmtpd-service-type
  19222. This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
  19223. service, whose value should be an @code{opensmtpd-configuration} object
  19224. as in this example:
  19225. @lisp
  19226. (service opensmtpd-service-type
  19227. (opensmtpd-configuration
  19228. (config-file (local-file "./my-smtpd.conf"))))
  19229. @end lisp
  19230. @end deffn
  19231. @deftp {Data Type} opensmtpd-configuration
  19232. Data type representing the configuration of opensmtpd.
  19233. @table @asis
  19234. @item @code{package} (default: @var{opensmtpd})
  19235. Package object of the OpenSMTPD SMTP server.
  19236. @item @code{config-file} (default: @code{%default-opensmtpd-config-file})
  19237. File-like object of the OpenSMTPD configuration file to use. By default
  19238. it listens on the loopback network interface, and allows for mail from
  19239. users and daemons on the local machine, as well as permitting email to
  19240. remote servers. Run @command{man smtpd.conf} for more information.
  19241. @end table
  19242. @end deftp
  19243. @subsubheading Exim Service
  19244. @cindex mail transfer agent (MTA)
  19245. @cindex MTA (mail transfer agent)
  19246. @cindex SMTP
  19247. @deffn {Scheme Variable} exim-service-type
  19248. This is the type of the @uref{https://exim.org, Exim} mail transfer
  19249. agent (MTA), whose value should be an @code{exim-configuration} object
  19250. as in this example:
  19251. @lisp
  19252. (service exim-service-type
  19253. (exim-configuration
  19254. (config-file (local-file "./my-exim.conf"))))
  19255. @end lisp
  19256. @end deffn
  19257. In order to use an @code{exim-service-type} service you must also have a
  19258. @code{mail-aliases-service-type} service present in your
  19259. @code{operating-system} (even if it has no aliases).
  19260. @deftp {Data Type} exim-configuration
  19261. Data type representing the configuration of exim.
  19262. @table @asis
  19263. @item @code{package} (default: @var{exim})
  19264. Package object of the Exim server.
  19265. @item @code{config-file} (default: @code{#f})
  19266. File-like object of the Exim configuration file to use. If its value is
  19267. @code{#f} then use the default configuration file from the package
  19268. provided in @code{package}. The resulting configuration file is loaded
  19269. after setting the @code{exim_user} and @code{exim_group} configuration
  19270. variables.
  19271. @end table
  19272. @end deftp
  19273. @subsubheading Getmail service
  19274. @cindex IMAP
  19275. @cindex POP
  19276. @deffn {Scheme Variable} getmail-service-type
  19277. This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
  19278. mail retriever, whose value should be an @code{getmail-configuration}.
  19279. @end deffn
  19280. Available @code{getmail-configuration} fields are:
  19281. @deftypevr {@code{getmail-configuration} parameter} symbol name
  19282. A symbol to identify the getmail service.
  19283. Defaults to @samp{"unset"}.
  19284. @end deftypevr
  19285. @deftypevr {@code{getmail-configuration} parameter} package package
  19286. The getmail package to use.
  19287. @end deftypevr
  19288. @deftypevr {@code{getmail-configuration} parameter} string user
  19289. The user to run getmail as.
  19290. Defaults to @samp{"getmail"}.
  19291. @end deftypevr
  19292. @deftypevr {@code{getmail-configuration} parameter} string group
  19293. The group to run getmail as.
  19294. Defaults to @samp{"getmail"}.
  19295. @end deftypevr
  19296. @deftypevr {@code{getmail-configuration} parameter} string directory
  19297. The getmail directory to use.
  19298. Defaults to @samp{"/var/lib/getmail/default"}.
  19299. @end deftypevr
  19300. @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
  19301. The getmail configuration file to use.
  19302. Available @code{getmail-configuration-file} fields are:
  19303. @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
  19304. What mail account to retrieve mail from, and how to access that account.
  19305. Available @code{getmail-retriever-configuration} fields are:
  19306. @deftypevr {@code{getmail-retriever-configuration} parameter} string type
  19307. The type of mail retriever to use. Valid values include @samp{passwd}
  19308. and @samp{static}.
  19309. Defaults to @samp{"SimpleIMAPSSLRetriever"}.
  19310. @end deftypevr
  19311. @deftypevr {@code{getmail-retriever-configuration} parameter} string server
  19312. Username to login to the mail server with.
  19313. Defaults to @samp{unset}.
  19314. @end deftypevr
  19315. @deftypevr {@code{getmail-retriever-configuration} parameter} string username
  19316. Username to login to the mail server with.
  19317. Defaults to @samp{unset}.
  19318. @end deftypevr
  19319. @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
  19320. Port number to connect to.
  19321. Defaults to @samp{#f}.
  19322. @end deftypevr
  19323. @deftypevr {@code{getmail-retriever-configuration} parameter} string password
  19324. Override fields from passwd.
  19325. Defaults to @samp{""}.
  19326. @end deftypevr
  19327. @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
  19328. Override fields from passwd.
  19329. Defaults to @samp{()}.
  19330. @end deftypevr
  19331. @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
  19332. PEM-formatted key file to use for the TLS negotiation.
  19333. Defaults to @samp{""}.
  19334. @end deftypevr
  19335. @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
  19336. PEM-formatted certificate file to use for the TLS negotiation.
  19337. Defaults to @samp{""}.
  19338. @end deftypevr
  19339. @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
  19340. CA certificates to use.
  19341. Defaults to @samp{""}.
  19342. @end deftypevr
  19343. @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
  19344. Extra retriever parameters.
  19345. Defaults to @samp{()}.
  19346. @end deftypevr
  19347. @end deftypevr
  19348. @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
  19349. What to do with retrieved messages.
  19350. Available @code{getmail-destination-configuration} fields are:
  19351. @deftypevr {@code{getmail-destination-configuration} parameter} string type
  19352. The type of mail destination. Valid values include @samp{Maildir},
  19353. @samp{Mboxrd} and @samp{MDA_external}.
  19354. Defaults to @samp{unset}.
  19355. @end deftypevr
  19356. @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
  19357. The path option for the mail destination. The behaviour depends on the
  19358. chosen type.
  19359. Defaults to @samp{""}.
  19360. @end deftypevr
  19361. @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
  19362. Extra destination parameters
  19363. Defaults to @samp{()}.
  19364. @end deftypevr
  19365. @end deftypevr
  19366. @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
  19367. Configure getmail.
  19368. Available @code{getmail-options-configuration} fields are:
  19369. @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
  19370. If set to @samp{0}, getmail will only print warnings and errors. A
  19371. value of @samp{1} means that messages will be printed about retrieving
  19372. and deleting messages. If set to @samp{2}, getmail will print messages
  19373. about each of its actions.
  19374. Defaults to @samp{1}.
  19375. @end deftypevr
  19376. @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
  19377. If true, getmail will retrieve all available messages. Otherwise it
  19378. will only retrieve messages it hasn't seen previously.
  19379. Defaults to @samp{#t}.
  19380. @end deftypevr
  19381. @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
  19382. If set to true, messages will be deleted from the server after
  19383. retrieving and successfully delivering them. Otherwise, messages will
  19384. be left on the server.
  19385. Defaults to @samp{#f}.
  19386. @end deftypevr
  19387. @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
  19388. Getmail will delete messages this number of days after seeing them, if
  19389. they have been delivered. This means messages will be left on the
  19390. server this number of days after delivering them. A value of @samp{0}
  19391. disabled this feature.
  19392. Defaults to @samp{0}.
  19393. @end deftypevr
  19394. @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
  19395. Delete messages larger than this of bytes after retrieving them, even if
  19396. the delete and delete-after options are disabled. A value of @samp{0}
  19397. disables this feature.
  19398. Defaults to @samp{0}.
  19399. @end deftypevr
  19400. @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
  19401. Retrieve messages totalling up to this number of bytes before closing
  19402. the session with the server. A value of @samp{0} disables this feature.
  19403. Defaults to @samp{0}.
  19404. @end deftypevr
  19405. @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
  19406. Don't retrieve messages larger than this number of bytes. A value of
  19407. @samp{0} disables this feature.
  19408. Defaults to @samp{0}.
  19409. @end deftypevr
  19410. @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
  19411. If true, getmail will add a Delivered-To header to messages.
  19412. Defaults to @samp{#t}.
  19413. @end deftypevr
  19414. @deftypevr {@code{getmail-options-configuration} parameter} boolean received
  19415. If set, getmail adds a Received header to the messages.
  19416. Defaults to @samp{#t}.
  19417. @end deftypevr
  19418. @deftypevr {@code{getmail-options-configuration} parameter} string message-log
  19419. Getmail will record a log of its actions to the named file. A value of
  19420. @samp{""} disables this feature.
  19421. Defaults to @samp{""}.
  19422. @end deftypevr
  19423. @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
  19424. If true, getmail will record a log of its actions using the system
  19425. logger.
  19426. Defaults to @samp{#f}.
  19427. @end deftypevr
  19428. @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
  19429. If true, getmail will log information about messages not retrieved and
  19430. the reason for not retrieving them, as well as starting and ending
  19431. information lines.
  19432. Defaults to @samp{#f}.
  19433. @end deftypevr
  19434. @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
  19435. Extra options to include.
  19436. Defaults to @samp{()}.
  19437. @end deftypevr
  19438. @end deftypevr
  19439. @end deftypevr
  19440. @deftypevr {@code{getmail-configuration} parameter} list idle
  19441. A list of mailboxes that getmail should wait on the server for new mail
  19442. notifications. This depends on the server supporting the IDLE
  19443. extension.
  19444. Defaults to @samp{()}.
  19445. @end deftypevr
  19446. @deftypevr {@code{getmail-configuration} parameter} list environment-variables
  19447. Environment variables to set for getmail.
  19448. Defaults to @samp{()}.
  19449. @end deftypevr
  19450. @subsubheading Mail Aliases Service
  19451. @cindex email aliases
  19452. @cindex aliases, for email addresses
  19453. @deffn {Scheme Variable} mail-aliases-service-type
  19454. This is the type of the service which provides @code{/etc/aliases},
  19455. specifying how to deliver mail to users on this system.
  19456. @lisp
  19457. (service mail-aliases-service-type
  19458. '(("postmaster" "bob")
  19459. ("bob" "bob@@example.com" "bob@@example2.com")))
  19460. @end lisp
  19461. @end deffn
  19462. The configuration for a @code{mail-aliases-service-type} service is an
  19463. association list denoting how to deliver mail that comes to this
  19464. system. Each entry is of the form @code{(alias addresses ...)}, with
  19465. @code{alias} specifying the local alias and @code{addresses} specifying
  19466. where to deliver this user's mail.
  19467. The aliases aren't required to exist as users on the local system. In
  19468. the above example, there doesn't need to be a @code{postmaster} entry in
  19469. the @code{operating-system}'s @code{user-accounts} in order to deliver
  19470. the @code{postmaster} mail to @code{bob} (which subsequently would
  19471. deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
  19472. @subsubheading GNU Mailutils IMAP4 Daemon
  19473. @cindex GNU Mailutils IMAP4 Daemon
  19474. @deffn {Scheme Variable} imap4d-service-type
  19475. This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
  19476. mailutils, GNU Mailutils Manual}), whose value should be an
  19477. @code{imap4d-configuration} object as in this example:
  19478. @lisp
  19479. (service imap4d-service-type
  19480. (imap4d-configuration
  19481. (config-file (local-file "imap4d.conf"))))
  19482. @end lisp
  19483. @end deffn
  19484. @deftp {Data Type} imap4d-configuration
  19485. Data type representing the configuration of @command{imap4d}.
  19486. @table @asis
  19487. @item @code{package} (default: @code{mailutils})
  19488. The package that provides @command{imap4d}.
  19489. @item @code{config-file} (default: @code{%default-imap4d-config-file})
  19490. File-like object of the configuration file to use, by default it will listen
  19491. on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
  19492. Mailutils Manual}, for details.
  19493. @end table
  19494. @end deftp
  19495. @subsubheading Radicale Service
  19496. @cindex CalDAV
  19497. @cindex CardDAV
  19498. @deffn {Scheme Variable} radicale-service-type
  19499. This is the type of the @uref{https://radicale.org, Radicale} CalDAV/CardDAV
  19500. server whose value should be a @code{radicale-configuration}.
  19501. @end deffn
  19502. @deftp {Data Type} radicale-configuration
  19503. Data type representing the configuration of @command{radicale}.
  19504. @table @asis
  19505. @item @code{package} (default: @code{radicale})
  19506. The package that provides @command{radicale}.
  19507. @item @code{config-file} (default: @code{%default-radicale-config-file})
  19508. File-like object of the configuration file to use, by default it will listen
  19509. on TCP port 5232 of @code{localhost} and use the @code{htpasswd} file at
  19510. @file{/var/lib/radicale/users} with no (@code{plain}) encryption.
  19511. @end table
  19512. @end deftp
  19513. @node Messaging Services
  19514. @subsection Messaging Services
  19515. @cindex messaging
  19516. @cindex jabber
  19517. @cindex XMPP
  19518. The @code{(gnu services messaging)} module provides Guix service
  19519. definitions for messaging services. Currently it provides the following
  19520. services:
  19521. @subsubheading Prosody Service
  19522. @deffn {Scheme Variable} prosody-service-type
  19523. This is the type for the @uref{https://prosody.im, Prosody XMPP
  19524. communication server}. Its value must be a @code{prosody-configuration}
  19525. record as in this example:
  19526. @lisp
  19527. (service prosody-service-type
  19528. (prosody-configuration
  19529. (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
  19530. (int-components
  19531. (list
  19532. (int-component-configuration
  19533. (hostname "conference.example.net")
  19534. (plugin "muc")
  19535. (mod-muc (mod-muc-configuration)))))
  19536. (virtualhosts
  19537. (list
  19538. (virtualhost-configuration
  19539. (domain "example.net"))))))
  19540. @end lisp
  19541. See below for details about @code{prosody-configuration}.
  19542. @end deffn
  19543. By default, Prosody does not need much configuration. Only one
  19544. @code{virtualhosts} field is needed: it specifies the domain you wish
  19545. Prosody to serve.
  19546. You can perform various sanity checks on the generated configuration
  19547. with the @code{prosodyctl check} command.
  19548. Prosodyctl will also help you to import certificates from the
  19549. @code{letsencrypt} directory so that the @code{prosody} user can access
  19550. them. See @url{https://prosody.im/doc/letsencrypt}.
  19551. @example
  19552. prosodyctl --root cert import /etc/letsencrypt/live
  19553. @end example
  19554. The available configuration parameters follow. Each parameter
  19555. definition is preceded by its type; for example, @samp{string-list foo}
  19556. indicates that the @code{foo} parameter should be specified as a list of
  19557. strings. Types starting with @code{maybe-} denote parameters that won't
  19558. show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
  19559. There is also a way to specify the configuration as a string, if you
  19560. have an old @code{prosody.cfg.lua} file that you want to port over from
  19561. some other system; see the end for more details.
  19562. The @code{file-object} type designates either a file-like object
  19563. (@pxref{G-Expressions, file-like objects}) or a file name.
  19564. @c The following documentation was initially generated by
  19565. @c (generate-documentation) in (gnu services messaging). Manually maintained
  19566. @c documentation is better, so we shouldn't hesitate to edit below as
  19567. @c needed. However if the change you want to make to this documentation
  19568. @c can be done in an automated way, it's probably easier to change
  19569. @c (generate-documentation) than to make it below and have to deal with
  19570. @c the churn as Prosody updates.
  19571. Available @code{prosody-configuration} fields are:
  19572. @deftypevr {@code{prosody-configuration} parameter} package prosody
  19573. The Prosody package.
  19574. @end deftypevr
  19575. @deftypevr {@code{prosody-configuration} parameter} file-name data-path
  19576. Location of the Prosody data storage directory. See
  19577. @url{https://prosody.im/doc/configure}.
  19578. Defaults to @samp{"/var/lib/prosody"}.
  19579. @end deftypevr
  19580. @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
  19581. Additional plugin directories. They are searched in all the specified
  19582. paths in order. See @url{https://prosody.im/doc/plugins_directory}.
  19583. Defaults to @samp{()}.
  19584. @end deftypevr
  19585. @deftypevr {@code{prosody-configuration} parameter} file-name certificates
  19586. Every virtual host and component needs a certificate so that clients and
  19587. servers can securely verify its identity. Prosody will automatically load
  19588. certificates/keys from the directory specified here.
  19589. Defaults to @samp{"/etc/prosody/certs"}.
  19590. @end deftypevr
  19591. @deftypevr {@code{prosody-configuration} parameter} string-list admins
  19592. This is a list of accounts that are admins for the server. Note that you
  19593. must create the accounts separately. See @url{https://prosody.im/doc/admins} and
  19594. @url{https://prosody.im/doc/creating_accounts}.
  19595. Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
  19596. Defaults to @samp{()}.
  19597. @end deftypevr
  19598. @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
  19599. Enable use of libevent for better performance under high load. See
  19600. @url{https://prosody.im/doc/libevent}.
  19601. Defaults to @samp{#f}.
  19602. @end deftypevr
  19603. @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
  19604. This is the list of modules Prosody will load on startup. It looks for
  19605. @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
  19606. Documentation on modules can be found at:
  19607. @url{https://prosody.im/doc/modules}.
  19608. Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
  19609. @end deftypevr
  19610. @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
  19611. @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
  19612. should you want to disable them then add them to this list.
  19613. Defaults to @samp{()}.
  19614. @end deftypevr
  19615. @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
  19616. Path to a text file where the shared groups are defined. If this path is
  19617. empty then @samp{mod_groups} does nothing. See
  19618. @url{https://prosody.im/doc/modules/mod_groups}.
  19619. Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
  19620. @end deftypevr
  19621. @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
  19622. Disable account creation by default, for security. See
  19623. @url{https://prosody.im/doc/creating_accounts}.
  19624. Defaults to @samp{#f}.
  19625. @end deftypevr
  19626. @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
  19627. These are the SSL/TLS-related settings. Most of them are disabled so to
  19628. use Prosody's defaults. If you do not completely understand these options, do
  19629. not add them to your config, it is easy to lower the security of your server
  19630. using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
  19631. Available @code{ssl-configuration} fields are:
  19632. @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
  19633. This determines what handshake to use.
  19634. @end deftypevr
  19635. @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
  19636. Path to your private key file.
  19637. @end deftypevr
  19638. @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
  19639. Path to your certificate file.
  19640. @end deftypevr
  19641. @deftypevr {@code{ssl-configuration} parameter} file-object capath
  19642. Path to directory containing root certificates that you wish Prosody to
  19643. trust when verifying the certificates of remote servers.
  19644. Defaults to @samp{"/etc/ssl/certs"}.
  19645. @end deftypevr
  19646. @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
  19647. Path to a file containing root certificates that you wish Prosody to trust.
  19648. Similar to @code{capath} but with all certificates concatenated together.
  19649. @end deftypevr
  19650. @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
  19651. A list of verification options (these mostly map to OpenSSL's
  19652. @code{set_verify()} flags).
  19653. @end deftypevr
  19654. @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
  19655. A list of general options relating to SSL/TLS@. These map to OpenSSL's
  19656. @code{set_options()}. For a full list of options available in LuaSec, see the
  19657. LuaSec source.
  19658. @end deftypevr
  19659. @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
  19660. How long a chain of certificate authorities to check when looking for a
  19661. trusted root certificate.
  19662. @end deftypevr
  19663. @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
  19664. An OpenSSL cipher string. This selects what ciphers Prosody will offer to
  19665. clients, and in what order.
  19666. @end deftypevr
  19667. @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
  19668. A path to a file containing parameters for Diffie-Hellman key exchange. You
  19669. can create such a file with:
  19670. @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
  19671. @end deftypevr
  19672. @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
  19673. Curve for Elliptic curve Diffie-Hellman. Prosody's default is
  19674. @samp{"secp384r1"}.
  19675. @end deftypevr
  19676. @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
  19677. A list of ``extra'' verification options.
  19678. @end deftypevr
  19679. @deftypevr {@code{ssl-configuration} parameter} maybe-string password
  19680. Password for encrypted private keys.
  19681. @end deftypevr
  19682. @end deftypevr
  19683. @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
  19684. Whether to force all client-to-server connections to be encrypted or not.
  19685. See @url{https://prosody.im/doc/modules/mod_tls}.
  19686. Defaults to @samp{#f}.
  19687. @end deftypevr
  19688. @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
  19689. Set of mechanisms that will never be offered. See
  19690. @url{https://prosody.im/doc/modules/mod_saslauth}.
  19691. Defaults to @samp{("DIGEST-MD5")}.
  19692. @end deftypevr
  19693. @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
  19694. Whether to force all server-to-server connections to be encrypted or not.
  19695. See @url{https://prosody.im/doc/modules/mod_tls}.
  19696. Defaults to @samp{#f}.
  19697. @end deftypevr
  19698. @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
  19699. Whether to require encryption and certificate authentication. This
  19700. provides ideal security, but requires servers you communicate with to support
  19701. encryption AND present valid, trusted certificates. See
  19702. @url{https://prosody.im/doc/s2s#security}.
  19703. Defaults to @samp{#f}.
  19704. @end deftypevr
  19705. @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
  19706. Many servers don't support encryption or have invalid or self-signed
  19707. certificates. You can list domains here that will not be required to
  19708. authenticate using certificates. They will be authenticated using DNS@. See
  19709. @url{https://prosody.im/doc/s2s#security}.
  19710. Defaults to @samp{()}.
  19711. @end deftypevr
  19712. @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
  19713. Even if you leave @code{s2s-secure-auth?} disabled, you can still require
  19714. valid certificates for some domains by specifying a list here. See
  19715. @url{https://prosody.im/doc/s2s#security}.
  19716. Defaults to @samp{()}.
  19717. @end deftypevr
  19718. @deftypevr {@code{prosody-configuration} parameter} string authentication
  19719. Select the authentication backend to use. The default provider stores
  19720. passwords in plaintext and uses Prosody's configured data storage to store the
  19721. authentication data. If you do not trust your server please see
  19722. @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
  19723. about using the hashed backend. See also
  19724. @url{https://prosody.im/doc/authentication}
  19725. Defaults to @samp{"internal_plain"}.
  19726. @end deftypevr
  19727. @deftypevr {@code{prosody-configuration} parameter} maybe-string log
  19728. Set logging options. Advanced logging configuration is not yet supported
  19729. by the Prosody service. See @url{https://prosody.im/doc/logging}.
  19730. Defaults to @samp{"*syslog"}.
  19731. @end deftypevr
  19732. @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
  19733. File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
  19734. Defaults to @samp{"/var/run/prosody/prosody.pid"}.
  19735. @end deftypevr
  19736. @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
  19737. Maximum allowed size of the HTTP body (in bytes).
  19738. @end deftypevr
  19739. @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
  19740. Some modules expose their own URL in various ways. This URL is built
  19741. from the protocol, host and port used. If Prosody sits behind a proxy, the
  19742. public URL will be @code{http-external-url} instead. See
  19743. @url{https://prosody.im/doc/http#external_url}.
  19744. @end deftypevr
  19745. @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
  19746. A host in Prosody is a domain on which user accounts can be created. For
  19747. example if you want your users to have addresses like
  19748. @samp{"john.smith@@example.com"} then you need to add a host
  19749. @samp{"example.com"}. All options in this list will apply only to this host.
  19750. Note: the name @emph{virtual} host is used in configuration to avoid confusion with
  19751. the actual physical host that Prosody is installed on. A single Prosody
  19752. instance can serve many domains, each one defined as a VirtualHost entry in
  19753. Prosody's configuration. Conversely a server that hosts a single domain would
  19754. have just one VirtualHost entry.
  19755. See @url{https://prosody.im/doc/configure#virtual_host_settings}.
  19756. Available @code{virtualhost-configuration} fields are:
  19757. all these @code{prosody-configuration} fields: @code{admins}, @code{use-libevent?}, @code{modules-enabled}, @code{modules-disabled}, @code{groups-file}, @code{allow-registration?}, @code{ssl}, @code{c2s-require-encryption?}, @code{disable-sasl-mechanisms}, @code{s2s-require-encryption?}, @code{s2s-secure-auth?}, @code{s2s-insecure-domains}, @code{s2s-secure-domains}, @code{authentication}, @code{log}, @code{http-max-content-size}, @code{http-external-url}, @code{raw-content}, plus:
  19758. @deftypevr {@code{virtualhost-configuration} parameter} string domain
  19759. Domain you wish Prosody to serve.
  19760. @end deftypevr
  19761. @end deftypevr
  19762. @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
  19763. Components are extra services on a server which are available to clients,
  19764. usually on a subdomain of the main server (such as
  19765. @samp{"mycomponent.example.com"}). Example components might be chatroom
  19766. servers, user directories, or gateways to other protocols.
  19767. Internal components are implemented with Prosody-specific plugins. To add an
  19768. internal component, you simply fill the hostname field, and the plugin you wish
  19769. to use for the component.
  19770. See @url{https://prosody.im/doc/components}.
  19771. Defaults to @samp{()}.
  19772. Available @code{int-component-configuration} fields are:
  19773. all these @code{prosody-configuration} fields: @code{admins}, @code{use-libevent?}, @code{modules-enabled}, @code{modules-disabled}, @code{groups-file}, @code{allow-registration?}, @code{ssl}, @code{c2s-require-encryption?}, @code{disable-sasl-mechanisms}, @code{s2s-require-encryption?}, @code{s2s-secure-auth?}, @code{s2s-insecure-domains}, @code{s2s-secure-domains}, @code{authentication}, @code{log}, @code{http-max-content-size}, @code{http-external-url}, @code{raw-content}, plus:
  19774. @deftypevr {@code{int-component-configuration} parameter} string hostname
  19775. Hostname of the component.
  19776. @end deftypevr
  19777. @deftypevr {@code{int-component-configuration} parameter} string plugin
  19778. Plugin you wish to use for the component.
  19779. @end deftypevr
  19780. @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
  19781. Multi-user chat (MUC) is Prosody's module for allowing you to create
  19782. hosted chatrooms/conferences for XMPP users.
  19783. General information on setting up and using multi-user chatrooms can be found
  19784. in the ``Chatrooms'' documentation (@url{https://prosody.im/doc/chatrooms}),
  19785. which you should read if you are new to XMPP chatrooms.
  19786. See also @url{https://prosody.im/doc/modules/mod_muc}.
  19787. Available @code{mod-muc-configuration} fields are:
  19788. @deftypevr {@code{mod-muc-configuration} parameter} string name
  19789. The name to return in service discovery responses.
  19790. Defaults to @samp{"Prosody Chatrooms"}.
  19791. @end deftypevr
  19792. @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
  19793. If @samp{#t}, this will only allow admins to create new chatrooms.
  19794. Otherwise anyone can create a room. The value @samp{"local"} restricts room
  19795. creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
  19796. can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
  19797. restricts to service administrators only.
  19798. Defaults to @samp{#f}.
  19799. @end deftypevr
  19800. @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
  19801. Maximum number of history messages that will be sent to the member that has
  19802. just joined the room.
  19803. Defaults to @samp{20}.
  19804. @end deftypevr
  19805. @end deftypevr
  19806. @end deftypevr
  19807. @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
  19808. External components use XEP-0114, which most standalone components
  19809. support. To add an external component, you simply fill the hostname field. See
  19810. @url{https://prosody.im/doc/components}.
  19811. Defaults to @samp{()}.
  19812. Available @code{ext-component-configuration} fields are:
  19813. all these @code{prosody-configuration} fields: @code{admins}, @code{use-libevent?}, @code{modules-enabled}, @code{modules-disabled}, @code{groups-file}, @code{allow-registration?}, @code{ssl}, @code{c2s-require-encryption?}, @code{disable-sasl-mechanisms}, @code{s2s-require-encryption?}, @code{s2s-secure-auth?}, @code{s2s-insecure-domains}, @code{s2s-secure-domains}, @code{authentication}, @code{log}, @code{http-max-content-size}, @code{http-external-url}, @code{raw-content}, plus:
  19814. @deftypevr {@code{ext-component-configuration} parameter} string component-secret
  19815. Password which the component will use to log in.
  19816. @end deftypevr
  19817. @deftypevr {@code{ext-component-configuration} parameter} string hostname
  19818. Hostname of the component.
  19819. @end deftypevr
  19820. @end deftypevr
  19821. @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
  19822. Port(s) Prosody listens on for component connections.
  19823. Defaults to @samp{(5347)}.
  19824. @end deftypevr
  19825. @deftypevr {@code{prosody-configuration} parameter} string component-interface
  19826. Interface Prosody listens on for component connections.
  19827. Defaults to @samp{"127.0.0.1"}.
  19828. @end deftypevr
  19829. @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
  19830. Raw content that will be added to the configuration file.
  19831. @end deftypevr
  19832. It could be that you just want to get a @code{prosody.cfg.lua}
  19833. up and running. In that case, you can pass an
  19834. @code{opaque-prosody-configuration} record as the value of
  19835. @code{prosody-service-type}. As its name indicates, an opaque configuration
  19836. does not have easy reflective capabilities.
  19837. Available @code{opaque-prosody-configuration} fields are:
  19838. @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
  19839. The prosody package.
  19840. @end deftypevr
  19841. @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
  19842. The contents of the @code{prosody.cfg.lua} to use.
  19843. @end deftypevr
  19844. For example, if your @code{prosody.cfg.lua} is just the empty
  19845. string, you could instantiate a prosody service like this:
  19846. @lisp
  19847. (service prosody-service-type
  19848. (opaque-prosody-configuration
  19849. (prosody.cfg.lua "")))
  19850. @end lisp
  19851. @c end of Prosody auto-generated documentation
  19852. @subsubheading BitlBee Service
  19853. @cindex IRC (Internet Relay Chat)
  19854. @cindex IRC gateway
  19855. @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
  19856. interface to a variety of messaging protocols such as XMPP.
  19857. @defvr {Scheme Variable} bitlbee-service-type
  19858. This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
  19859. gateway daemon. Its value is a @code{bitlbee-configuration} (see
  19860. below).
  19861. To have BitlBee listen on port 6667 on localhost, add this line to your
  19862. services:
  19863. @lisp
  19864. (service bitlbee-service-type)
  19865. @end lisp
  19866. @end defvr
  19867. @deftp {Data Type} bitlbee-configuration
  19868. This is the configuration for BitlBee, with the following fields:
  19869. @table @asis
  19870. @item @code{interface} (default: @code{"127.0.0.1"})
  19871. @itemx @code{port} (default: @code{6667})
  19872. Listen on the network interface corresponding to the IP address
  19873. specified in @var{interface}, on @var{port}.
  19874. When @var{interface} is @code{127.0.0.1}, only local clients can
  19875. connect; when it is @code{0.0.0.0}, connections can come from any
  19876. networking interface.
  19877. @item @code{bitlbee} (default: @code{bitlbee})
  19878. The BitlBee package to use.
  19879. @item @code{plugins} (default: @code{'()})
  19880. List of plugin packages to use---e.g., @code{bitlbee-discord}.
  19881. @item @code{extra-settings} (default: @code{""})
  19882. Configuration snippet added as-is to the BitlBee configuration file.
  19883. @end table
  19884. @end deftp
  19885. @subsubheading Quassel Service
  19886. @cindex IRC (Internet Relay Chat)
  19887. @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
  19888. meaning that one or more clients can attach to and detach from the
  19889. central core.
  19890. @defvr {Scheme Variable} quassel-service-type
  19891. This is the service type for the @url{https://quassel-irc.org/,Quassel}
  19892. IRC backend daemon. Its value is a @code{quassel-configuration}
  19893. (see below).
  19894. @end defvr
  19895. @deftp {Data Type} quassel-configuration
  19896. This is the configuration for Quassel, with the following fields:
  19897. @table @asis
  19898. @item @code{quassel} (default: @code{quassel})
  19899. The Quassel package to use.
  19900. @item @code{interface} (default: @code{"::,0.0.0.0"})
  19901. @item @code{port} (default: @code{4242})
  19902. Listen on the network interface(s) corresponding to the IPv4 or IPv6
  19903. interfaces specified in the comma delimited @var{interface}, on
  19904. @var{port}.
  19905. @item @code{loglevel} (default: @code{"Info"})
  19906. The level of logging desired. Accepted values are Debug, Info, Warning
  19907. and Error.
  19908. @end table
  19909. @end deftp
  19910. @node Telephony Services
  19911. @subsection Telephony Services
  19912. @cindex telephony, services
  19913. The @code{(gnu services telephony)} module contains Guix service
  19914. definitions for telephony services. Currently it provides the following
  19915. services:
  19916. @subsubheading Jami
  19917. @cindex jami, service
  19918. This section describes how to configure a Jami server that can be used
  19919. to host video (or audio) conferences, among other uses. The following
  19920. example demonstrates how to specify Jami account archives (backups) to
  19921. be provisioned automatically:
  19922. @lisp
  19923. (service jami-service-type
  19924. (jami-configuration
  19925. (accounts
  19926. (list (jami-account
  19927. (archive "/etc/jami/unencrypted-account-1.gz"))
  19928. (jami-account
  19929. (archive "/etc/jami/unencrypted-account-2.gz"))))))
  19930. @end lisp
  19931. When the accounts field is specified, the Jami account files of the
  19932. service found under @file{/var/lib/jami} are recreated every time the
  19933. service starts.
  19934. Jami accounts and their corresponding backup archives can be generated
  19935. using the @code{jami} or @code{jami-gnome} Jami clients. The accounts
  19936. should not be password-protected, but it is wise to ensure their files
  19937. are only readable by @samp{root}.
  19938. The next example shows how to declare that only some contacts should be
  19939. allowed to communicate with a given account:
  19940. @lisp
  19941. (service jami-service-type
  19942. (jami-configuration
  19943. (accounts
  19944. (list (jami-account
  19945. (archive "/etc/jami/unencrypted-account-1.gz")
  19946. (peer-discovery? #t)
  19947. (rendezvous-point? #t)
  19948. (allowed-contacts
  19949. '("1dbcb0f5f37324228235564b79f2b9737e9a008f"
  19950. "2dbcb0f5f37324228235564b79f2b9737e9a008f")))))))
  19951. @end lisp
  19952. In this mode, only the declared @code{allowed-contacts} can initiate
  19953. communication with the Jami account. This can be used, for example,
  19954. with rendezvous point accounts to create a private video conferencing
  19955. space.
  19956. To put the system administrator in full control of the conferences
  19957. hosted on their system, the Jami service supports the following actions:
  19958. @example sh
  19959. # herd doc jami list-actions
  19960. (list-accounts
  19961. list-account-details
  19962. list-banned-contacts
  19963. list-contacts
  19964. list-moderators
  19965. add-moderator
  19966. ban-contact
  19967. enable-account
  19968. disable-account)
  19969. @end example
  19970. The above actions aim to provide the most valuable actions for
  19971. moderation purposes, not to cover the whole Jami API. Users wanting to
  19972. interact with the Jami daemon from Guile may be interested in
  19973. experimenting with the @code{(gnu build jami-service)} module, which
  19974. powers the above Shepherd actions.
  19975. @c TODO: This should be auto-generated from the doc already defined on
  19976. @c the shepherd-actions themselves in (gnu services telephony).
  19977. The @code{add-moderator} and @code{ban-contact} actions accept a contact
  19978. @emph{fingerprint} (40 characters long hash) as first argument and an
  19979. account fingerprint or username as second argument:
  19980. @example sh
  19981. # herd add-moderator jami 1dbcb0f5f37324228235564b79f2b9737e9a008f \
  19982. f3345f2775ddfe07a4b0d95daea111d15fbc1199
  19983. # herd list-moderators jami
  19984. Moderators for account f3345f2775ddfe07a4b0d95daea111d15fbc1199:
  19985. - 1dbcb0f5f37324228235564b79f2b9737e9a008f
  19986. @end example
  19987. In the case of @code{ban-contact}, the second username argument is
  19988. optional; when omitted, the account is banned from all Jami accounts:
  19989. @example sh
  19990. # herd ban-contact jami 1dbcb0f5f37324228235564b79f2b9737e9a008f
  19991. # herd list-banned-contacts jami
  19992. Banned contacts for account f3345f2775ddfe07a4b0d95daea111d15fbc1199:
  19993. - 1dbcb0f5f37324228235564b79f2b9737e9a008f
  19994. @end example
  19995. Banned contacts are also stripped from their moderation privileges.
  19996. The @code{disable-account} action allows to completely disconnect an
  19997. account from the network, making it unreachable, while
  19998. @code{enable-account} does the inverse. They accept a single account
  19999. username or fingerprint as first argument:
  20000. @example sh
  20001. # herd disable-account jami f3345f2775ddfe07a4b0d95daea111d15fbc1199
  20002. # herd list-accounts jami
  20003. The following Jami accounts are available:
  20004. - f3345f2775ddfe07a4b0d95daea111d15fbc1199 (dummy) [disabled]
  20005. @end example
  20006. The @code{list-account-details} action prints the detailed parameters of
  20007. each accounts in the Recutils format, which means the @command{recsel}
  20008. command can be used to select accounts of interest (@pxref{Selection
  20009. Expressions,,,recutils, GNU recutils manual}). Note that period
  20010. characters (@samp{.}) found in the account parameter keys are mapped to
  20011. underscores (@samp{_}) in the output, to meet the requirements of the
  20012. Recutils format. The following example shows how to print the account
  20013. fingerprints for all accounts operating in the rendezvous point mode:
  20014. @example sh
  20015. # herd list-account-details jami | \
  20016. recsel -p Account.username -e 'Account.rendezVous ~ "true"'
  20017. Account_username: f3345f2775ddfe07a4b0d95daea111d15fbc1199
  20018. @end example
  20019. The remaining actions should be self-explanatory.
  20020. The complete set of available configuration options is detailed below.
  20021. @c TODO: Ideally, the following fragments would be auto-generated at
  20022. @c build time, so that they needn't be manually duplicated.
  20023. @c Auto-generated via (configuration->documentation 'jami-configuration)
  20024. @deftp {Data Type} jami-configuration
  20025. Available @code{jami-configuration} fields are:
  20026. @table @asis
  20027. @item @code{jamid} (default: @code{libjami}) (type: package)
  20028. The Jami daemon package to use.
  20029. @item @code{dbus} (default: @code{dbus}) (type: package)
  20030. The D-Bus package to use to start the required D-Bus session.
  20031. @item @code{nss-certs} (default: @code{nss-certs}) (type: package)
  20032. The nss-certs package to use to provide TLS certificates.
  20033. @item @code{enable-logging?} (default: @code{#t}) (type: boolean)
  20034. Whether to enable logging to syslog.
  20035. @item @code{debug?} (default: @code{#f}) (type: boolean)
  20036. Whether to enable debug level messages.
  20037. @item @code{auto-answer?} (default: @code{#f}) (type: boolean)
  20038. Whether to force automatic answer to incoming calls.
  20039. @item @code{accounts} (default: @code{disabled}) (type: maybe-jami-account-list)
  20040. A list of Jami accounts to be (re-)provisioned every time the Jami
  20041. daemon service starts. When providing this field, the account
  20042. directories under @file{/var/lib/jami/} are recreated every time the
  20043. service starts, ensuring a consistent state.
  20044. @end table
  20045. @end deftp
  20046. @c Auto-generated via (configuration->documentation 'jami-account)
  20047. @deftp {Data Type} jami-account
  20048. Available @code{jami-account} fields are:
  20049. @table @asis
  20050. @item @code{archive} (type: string-or-computed-file)
  20051. The account archive (backup) file name of the account. This is used to
  20052. provision the account when the service starts. The account archive
  20053. should @emph{not} be encrypted. It is highly recommended to make it
  20054. readable only to the @samp{root} user (i.e., not in the store), to guard
  20055. against leaking the secret key material of the Jami account it contains.
  20056. @item @code{allowed-contacts} (default: @code{disabled}) (type: maybe-account-fingerprint-list)
  20057. The list of allowed contacts for the account, entered as their 40
  20058. characters long fingerprint. Messages or calls from accounts not in
  20059. that list will be rejected. When unspecified, the configuration of the
  20060. account archive is used as-is with respect to contacts and public
  20061. inbound calls/messaging allowance, which typically defaults to allow any
  20062. contact to communicate with the account.
  20063. @item @code{moderators} (default: @code{disabled}) (type: maybe-account-fingerprint-list)
  20064. The list of contacts that should have moderation privileges (to ban,
  20065. mute, etc. other users) in rendezvous conferences, entered as their 40
  20066. characters long fingerprint. When unspecified, the configuration of the
  20067. account archive is used as-is with respect to moderation, which
  20068. typically defaults to allow anyone to moderate.
  20069. @item @code{rendezvous-point?} (default: @code{disabled}) (type: maybe-boolean)
  20070. Whether the account should operate in the rendezvous mode. In this
  20071. mode, all the incoming audio/video calls are mixed into a conference.
  20072. When left unspecified, the value from the account archive prevails.
  20073. @item @code{peer-discovery?} (default: @code{disabled}) (type: maybe-boolean)
  20074. Whether peer discovery should be enabled. Peer discovery is used to
  20075. discover other OpenDHT nodes on the local network, which can be useful
  20076. to maintain communication between devices on such network even when the
  20077. connection to the the Internet has been lost. When left unspecified,
  20078. the value from the account archive prevails.
  20079. @item @code{bootstrap-hostnames} (default: @code{disabled}) (type: maybe-string-list)
  20080. A list of hostnames or IPs pointing to OpenDHT nodes, that should be
  20081. used to initially join the OpenDHT network. When left unspecified, the
  20082. value from the account archive prevails.
  20083. @item @code{name-server-uri} (default: @code{disabled}) (type: maybe-string)
  20084. The URI of the name server to use, that can be used to retrieve the
  20085. account fingerprint for a registered username.
  20086. @end table
  20087. @end deftp
  20088. @subsubheading Murmur (VoIP server)
  20089. @cindex Murmur (VoIP server)
  20090. @cindex VoIP server
  20091. This section describes how to set up and run a Murmur server. Murmur is
  20092. the server of the @uref{https://mumble.info, Mumble} voice-over-IP
  20093. (VoIP) suite.
  20094. @deftp {Data Type} murmur-configuration
  20095. The service type for the Murmur server. An example configuration can
  20096. look like this:
  20097. @lisp
  20098. (service murmur-service-type
  20099. (murmur-configuration
  20100. (welcome-text
  20101. "Welcome to this Mumble server running on Guix!")
  20102. (cert-required? #t) ;disallow text password logins
  20103. (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
  20104. (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
  20105. @end lisp
  20106. After reconfiguring your system, you can manually set the murmur @code{SuperUser}
  20107. password with the command that is printed during the activation phase.
  20108. It is recommended to register a normal Mumble user account
  20109. and grant it admin or moderator rights.
  20110. You can use the @code{mumble} client to
  20111. login as new normal user, register yourself, and log out.
  20112. For the next step login with the name @code{SuperUser} use
  20113. the @code{SuperUser} password that you set previously,
  20114. and grant your newly registered mumble user administrator or moderator
  20115. rights and create some channels.
  20116. Available @code{murmur-configuration} fields are:
  20117. @table @asis
  20118. @item @code{package} (default: @code{mumble})
  20119. Package that contains @code{bin/murmurd}.
  20120. @item @code{user} (default: @code{"murmur"})
  20121. User who will run the Murmur server.
  20122. @item @code{group} (default: @code{"murmur"})
  20123. Group of the user who will run the murmur server.
  20124. @item @code{port} (default: @code{64738})
  20125. Port on which the server will listen.
  20126. @item @code{welcome-text} (default: @code{""})
  20127. Welcome text sent to clients when they connect.
  20128. @item @code{server-password} (default: @code{""})
  20129. Password the clients have to enter in order to connect.
  20130. @item @code{max-users} (default: @code{100})
  20131. Maximum of users that can be connected to the server at once.
  20132. @item @code{max-user-bandwidth} (default: @code{#f})
  20133. Maximum voice traffic a user can send per second.
  20134. @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
  20135. File name of the sqlite database.
  20136. The service's user will become the owner of the directory.
  20137. @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
  20138. File name of the log file.
  20139. The service's user will become the owner of the directory.
  20140. @item @code{autoban-attempts} (default: @code{10})
  20141. Maximum number of logins a user can make in @code{autoban-timeframe}
  20142. without getting auto banned for @code{autoban-time}.
  20143. @item @code{autoban-timeframe} (default: @code{120})
  20144. Timeframe for autoban in seconds.
  20145. @item @code{autoban-time} (default: @code{300})
  20146. Amount of time in seconds for which a client gets banned
  20147. when violating the autoban limits.
  20148. @item @code{opus-threshold} (default: @code{100})
  20149. Percentage of clients that need to support opus
  20150. before switching over to opus audio codec.
  20151. @item @code{channel-nesting-limit} (default: @code{10})
  20152. How deep channels can be nested at maximum.
  20153. @item @code{channelname-regex} (default: @code{#f})
  20154. A string in form of a Qt regular expression that channel names must conform to.
  20155. @item @code{username-regex} (default: @code{#f})
  20156. A string in form of a Qt regular expression that user names must conform to.
  20157. @item @code{text-message-length} (default: @code{5000})
  20158. Maximum size in bytes that a user can send in one text chat message.
  20159. @item @code{image-message-length} (default: @code{(* 128 1024)})
  20160. Maximum size in bytes that a user can send in one image message.
  20161. @item @code{cert-required?} (default: @code{#f})
  20162. If it is set to @code{#t} clients that use weak password authentication
  20163. will not be accepted. Users must have completed the certificate wizard to join.
  20164. @item @code{remember-channel?} (default: @code{#f})
  20165. Should murmur remember the last channel each user was in when they disconnected
  20166. and put them into the remembered channel when they rejoin.
  20167. @item @code{allow-html?} (default: @code{#f})
  20168. Should html be allowed in text messages, user comments, and channel descriptions.
  20169. @item @code{allow-ping?} (default: @code{#f})
  20170. Setting to true exposes the current user count, the maximum user count, and
  20171. the server's maximum bandwidth per client to unauthenticated users. In the
  20172. Mumble client, this information is shown in the Connect dialog.
  20173. Disabling this setting will prevent public listing of the server.
  20174. @item @code{bonjour?} (default: @code{#f})
  20175. Should the server advertise itself in the local network through the bonjour protocol.
  20176. @item @code{send-version?} (default: @code{#f})
  20177. Should the murmur server version be exposed in ping requests.
  20178. @item @code{log-days} (default: @code{31})
  20179. Murmur also stores logs in the database, which are accessible via RPC.
  20180. The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
  20181. or -1 to disable logging to the database.
  20182. @item @code{obfuscate-ips?} (default: @code{#t})
  20183. Should logged ips be obfuscated to protect the privacy of users.
  20184. @item @code{ssl-cert} (default: @code{#f})
  20185. File name of the SSL/TLS certificate used for encrypted connections.
  20186. @lisp
  20187. (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
  20188. @end lisp
  20189. @item @code{ssl-key} (default: @code{#f})
  20190. Filepath to the ssl private key used for encrypted connections.
  20191. @lisp
  20192. (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
  20193. @end lisp
  20194. @item @code{ssl-dh-params} (default: @code{#f})
  20195. File name of a PEM-encoded file with Diffie-Hellman parameters
  20196. for the SSL/TLS encryption. Alternatively you set it to
  20197. @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
  20198. or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
  20199. @item @code{ssl-ciphers} (default: @code{#f})
  20200. The @code{ssl-ciphers} option chooses the cipher suites to make available for use
  20201. in SSL/TLS.
  20202. This option is specified using
  20203. @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
  20204. OpenSSL cipher list notation}.
  20205. It is recommended that you try your cipher string using 'openssl ciphers <string>'
  20206. before setting it here, to get a feel for which cipher suites you will get.
  20207. After setting this option, it is recommend that you inspect your Murmur log
  20208. to ensure that Murmur is using the cipher suites that you expected it to.
  20209. Note: Changing this option may impact the backwards compatibility of your
  20210. Murmur server, and can remove the ability for older Mumble clients to be able
  20211. to connect to it.
  20212. @item @code{public-registration} (default: @code{#f})
  20213. Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
  20214. You can optionally register your server in the public server list that the
  20215. @code{mumble} client shows on startup.
  20216. You cannot register your server if you have set a @code{server-password},
  20217. or set @code{allow-ping} to @code{#f}.
  20218. It might take a few hours until it shows up in the public list.
  20219. @item @code{file} (default: @code{#f})
  20220. Optional alternative override for this configuration.
  20221. @end table
  20222. @end deftp
  20223. @deftp {Data Type} murmur-public-registration-configuration
  20224. Configuration for public registration of a murmur service.
  20225. @table @asis
  20226. @item @code{name}
  20227. This is a display name for your server. Not to be confused with the hostname.
  20228. @item @code{password}
  20229. A password to identify your registration.
  20230. Subsequent updates will need the same password. Don't lose your password.
  20231. @item @code{url}
  20232. This should be a @code{http://} or @code{https://} link to your web
  20233. site.
  20234. @item @code{hostname} (default: @code{#f})
  20235. By default your server will be listed by its IP address.
  20236. If it is set your server will be linked by this host name instead.
  20237. @end table
  20238. @end deftp
  20239. @node File-Sharing Services
  20240. @subsection File-Sharing Services
  20241. The @code{(gnu services file-sharing)} module provides services that
  20242. assist with transferring files over peer-to-peer file-sharing networks.
  20243. @subsubheading Transmission Daemon Service
  20244. @uref{https://transmissionbt.com/, Transmission} is a flexible
  20245. BitTorrent client that offers a variety of graphical and command-line
  20246. interfaces. A @code{transmission-daemon-service-type} service provides
  20247. Transmission's headless variant, @command{transmission-daemon}, as a
  20248. system service, allowing users to share files via BitTorrent even when
  20249. they are not logged in.
  20250. @deffn {Scheme Variable} transmission-daemon-service-type
  20251. The service type for the Transmission Daemon BitTorrent client. Its
  20252. value must be a @code{transmission-daemon-configuration} object as in
  20253. this example:
  20254. @lisp
  20255. (service transmission-daemon-service-type
  20256. (transmission-daemon-configuration
  20257. ;; Restrict access to the RPC ("control") interface
  20258. (rpc-authentication-required? #t)
  20259. (rpc-username "transmission")
  20260. (rpc-password
  20261. (transmission-password-hash
  20262. "transmission" ; desired password
  20263. "uKd1uMs9")) ; arbitrary salt value
  20264. ;; Accept requests from this and other hosts on the
  20265. ;; local network
  20266. (rpc-whitelist-enabled? #t)
  20267. (rpc-whitelist '("::1" "127.0.0.1" "192.168.0.*"))
  20268. ;; Limit bandwidth use during work hours
  20269. (alt-speed-down (* 1024 2)) ; 2 MB/s
  20270. (alt-speed-up 512) ; 512 kB/s
  20271. (alt-speed-time-enabled? #t)
  20272. (alt-speed-time-day 'weekdays)
  20273. (alt-speed-time-begin
  20274. (+ (* 60 8) 30)) ; 8:30 am
  20275. (alt-speed-time-end
  20276. (+ (* 60 (+ 12 5)) 30)))) ; 5:30 pm
  20277. @end lisp
  20278. @end deffn
  20279. Once the service is started, users can interact with the daemon through
  20280. its Web interface (at @code{http://localhost:9091/}) or by using the
  20281. @command{transmission-remote} command-line tool, available in the
  20282. @code{transmission} package. (Emacs users may want to also consider the
  20283. @code{emacs-transmission} package.) Both communicate with the daemon
  20284. through its remote procedure call (RPC) interface, which by default is
  20285. available to all users on the system; you may wish to change this by
  20286. assigning values to the @code{rpc-authentication-required?},
  20287. @code{rpc-username} and @code{rpc-password} settings, as shown in the
  20288. example above and documented further below.
  20289. The value for @code{rpc-password} must be a password hash of the type
  20290. generated and used by Transmission clients. This can be copied verbatim
  20291. from an existing @file{settings.json} file, if another Transmission
  20292. client is already being used. Otherwise, the
  20293. @code{transmission-password-hash} and @code{transmission-random-salt}
  20294. procedures provided by this module can be used to obtain a suitable hash
  20295. value.
  20296. @deffn {Scheme Procedure} transmission-password-hash @var{password} @var{salt}
  20297. Returns a string containing the result of hashing @var{password}
  20298. together with @var{salt}, in the format recognized by Transmission
  20299. clients for their @code{rpc-password} configuration setting.
  20300. @var{salt} must be an eight-character string. The
  20301. @code{transmission-random-salt} procedure can be used to generate a
  20302. suitable salt value at random.
  20303. @end deffn
  20304. @deffn {Scheme Procedure} transmission-random-salt
  20305. Returns a string containing a random, eight-character salt value of the
  20306. type generated and used by Transmission clients, suitable for passing to
  20307. the @code{transmission-password-hash} procedure.
  20308. @end deffn
  20309. These procedures are accessible from within a Guile REPL started with
  20310. the @command{guix repl} command (@pxref{Invoking guix repl}). This is
  20311. useful for obtaining a random salt value to provide as the second
  20312. parameter to `transmission-password-hash`, as in this example session:
  20313. @example
  20314. $ guix repl
  20315. scheme@@(guix-user)> ,use (gnu services file-sharing)
  20316. scheme@@(guix-user)> (transmission-random-salt)
  20317. $1 = "uKd1uMs9"
  20318. @end example
  20319. Alternatively, a complete password hash can generated in a single step:
  20320. @example
  20321. scheme@@(guix-user)> (transmission-password-hash "transmission"
  20322. (transmission-random-salt))
  20323. $2 = "@{c8bbc6d1740cd8dc819a6e25563b67812c1c19c9VtFPfdsX"
  20324. @end example
  20325. The resulting string can be used as-is for the value of
  20326. @code{rpc-password}, allowing the password to be kept hidden even in the
  20327. operating-system configuration.
  20328. Torrent files downloaded by the daemon are directly accessible only to
  20329. users in the ``transmission'' user group, who receive read-only access
  20330. to the directory specified by the @code{download-dir} configuration
  20331. setting (and also the directory specified by @code{incomplete-dir}, if
  20332. @code{incomplete-dir-enabled?} is @code{#t}). Downloaded files can be
  20333. moved to another directory or deleted altogether using
  20334. @command{transmission-remote} with its @code{--move} and
  20335. @code{--remove-and-delete} options.
  20336. If the @code{watch-dir-enabled?} setting is set to @code{#t}, users in
  20337. the ``transmission'' group are able also to place @file{.torrent} files
  20338. in the directory specified by @code{watch-dir} to have the corresponding
  20339. torrents added by the daemon. (The @code{trash-original-torrent-files?}
  20340. setting controls whether the daemon deletes these files after processing
  20341. them.)
  20342. Some of the daemon's configuration settings can be changed temporarily
  20343. by @command{transmission-remote} and similar tools. To undo these
  20344. changes, use the service's @code{reload} action to have the daemon
  20345. reload its settings from disk:
  20346. @example
  20347. # herd reload transmission-daemon
  20348. @end example
  20349. The full set of available configuration settings is defined by the
  20350. @code{transmission-daemon-configuration} data type.
  20351. @deftp {Data Type} transmission-daemon-configuration
  20352. The data type representing configuration settings for Transmission
  20353. Daemon. These correspond directly to the settings recognized by
  20354. Transmission clients in their @file{settings.json} file.
  20355. @end deftp
  20356. @c The following documentation was initially generated by
  20357. @c (generate-transmission-daemon-documentation) in (gnu services
  20358. @c file-sharing). Manually maintained documentation is better, so we
  20359. @c shouldn't hesitate to edit below as needed. However if the change
  20360. @c you want to make to this documentation can be done in an automated
  20361. @c way, it's probably easier to change (generate-documentation) than to
  20362. @c make it below and have to deal with the churn as Transmission Daemon
  20363. @c updates.
  20364. @c %start of fragment
  20365. Available @code{transmission-daemon-configuration} fields are:
  20366. @deftypevr {@code{transmission-daemon-configuration} parameter} package transmission
  20367. The Transmission package to use.
  20368. @end deftypevr
  20369. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer stop-wait-period
  20370. The period, in seconds, to wait when stopping the service for
  20371. @command{transmission-daemon} to exit before killing its process. This
  20372. allows the daemon time to complete its housekeeping and send a final
  20373. update to trackers as it shuts down. On slow hosts, or hosts with a
  20374. slow network connection, this value may need to be increased.
  20375. Defaults to @samp{10}.
  20376. @end deftypevr
  20377. @deftypevr {@code{transmission-daemon-configuration} parameter} string download-dir
  20378. The directory to which torrent files are downloaded.
  20379. Defaults to @samp{"/var/lib/transmission-daemon/downloads"}.
  20380. @end deftypevr
  20381. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean incomplete-dir-enabled?
  20382. If @code{#t}, files will be held in @code{incomplete-dir} while their
  20383. torrent is being downloaded, then moved to @code{download-dir} once the
  20384. torrent is complete. Otherwise, files for all torrents (including those
  20385. still being downloaded) will be placed in @code{download-dir}.
  20386. Defaults to @samp{#f}.
  20387. @end deftypevr
  20388. @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string incomplete-dir
  20389. The directory in which files from incompletely downloaded torrents will
  20390. be held when @code{incomplete-dir-enabled?} is @code{#t}.
  20391. Defaults to @samp{disabled}.
  20392. @end deftypevr
  20393. @deftypevr {@code{transmission-daemon-configuration} parameter} umask umask
  20394. The file mode creation mask used for downloaded files. (See the
  20395. @command{umask} man page for more information.)
  20396. Defaults to @samp{18}.
  20397. @end deftypevr
  20398. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rename-partial-files?
  20399. When @code{#t}, ``.part'' is appended to the name of partially
  20400. downloaded files.
  20401. Defaults to @samp{#t}.
  20402. @end deftypevr
  20403. @deftypevr {@code{transmission-daemon-configuration} parameter} preallocation-mode preallocation
  20404. The mode by which space should be preallocated for downloaded files, one
  20405. of @code{none}, @code{fast} (or @code{sparse}) and @code{full}.
  20406. Specifying @code{full} will minimize disk fragmentation at a cost to
  20407. file-creation speed.
  20408. Defaults to @samp{fast}.
  20409. @end deftypevr
  20410. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean watch-dir-enabled?
  20411. If @code{#t}, the directory specified by @code{watch-dir} will be
  20412. watched for new @file{.torrent} files and the torrents they describe
  20413. added automatically (and the original files removed, if
  20414. @code{trash-original-torrent-files?} is @code{#t}).
  20415. Defaults to @samp{#f}.
  20416. @end deftypevr
  20417. @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string watch-dir
  20418. The directory to be watched for @file{.torrent} files indicating new
  20419. torrents to be added, when @code{watch-dir-enabled} is @code{#t}.
  20420. Defaults to @samp{disabled}.
  20421. @end deftypevr
  20422. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean trash-original-torrent-files?
  20423. When @code{#t}, @file{.torrent} files will be deleted from the watch
  20424. directory once their torrent has been added (see
  20425. @code{watch-directory-enabled?}).
  20426. Defaults to @samp{#f}.
  20427. @end deftypevr
  20428. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-down-enabled?
  20429. When @code{#t}, the daemon's download speed will be limited to the rate
  20430. specified by @code{speed-limit-down}.
  20431. Defaults to @samp{#f}.
  20432. @end deftypevr
  20433. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-down
  20434. The default global-maximum download speed, in kilobytes per second.
  20435. Defaults to @samp{100}.
  20436. @end deftypevr
  20437. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-up-enabled?
  20438. When @code{#t}, the daemon's upload speed will be limited to the rate
  20439. specified by @code{speed-limit-up}.
  20440. Defaults to @samp{#f}.
  20441. @end deftypevr
  20442. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-up
  20443. The default global-maximum upload speed, in kilobytes per second.
  20444. Defaults to @samp{100}.
  20445. @end deftypevr
  20446. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-enabled?
  20447. When @code{#t}, the alternate speed limits @code{alt-speed-down} and
  20448. @code{alt-speed-up} are used (in place of @code{speed-limit-down} and
  20449. @code{speed-limit-up}, if they are enabled) to constrain the daemon's
  20450. bandwidth usage. This can be scheduled to occur automatically at
  20451. certain times during the week; see @code{alt-speed-time-enabled?}.
  20452. Defaults to @samp{#f}.
  20453. @end deftypevr
  20454. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-down
  20455. The alternate global-maximum download speed, in kilobytes per second.
  20456. Defaults to @samp{50}.
  20457. @end deftypevr
  20458. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-up
  20459. The alternate global-maximum upload speed, in kilobytes per second.
  20460. Defaults to @samp{50}.
  20461. @end deftypevr
  20462. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-time-enabled?
  20463. When @code{#t}, the alternate speed limits @code{alt-speed-down} and
  20464. @code{alt-speed-up} will be enabled automatically during the periods
  20465. specified by @code{alt-speed-time-day}, @code{alt-speed-time-begin} and
  20466. @code{alt-time-speed-end}.
  20467. Defaults to @samp{#f}.
  20468. @end deftypevr
  20469. @deftypevr {@code{transmission-daemon-configuration} parameter} day-list alt-speed-time-day
  20470. The days of the week on which the alternate-speed schedule should be
  20471. used, specified either as a list of days (@code{sunday}, @code{monday},
  20472. and so on) or using one of the symbols @code{weekdays}, @code{weekends}
  20473. or @code{all}.
  20474. Defaults to @samp{all}.
  20475. @end deftypevr
  20476. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-begin
  20477. The time of day at which to enable the alternate speed limits, expressed
  20478. as a number of minutes since midnight.
  20479. Defaults to @samp{540}.
  20480. @end deftypevr
  20481. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-end
  20482. The time of day at which to disable the alternate speed limits,
  20483. expressed as a number of minutes since midnight.
  20484. Defaults to @samp{1020}.
  20485. @end deftypevr
  20486. @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv4
  20487. The IP address at which to listen for peer connections, or ``0.0.0.0''
  20488. to listen at all available IP addresses.
  20489. Defaults to @samp{"0.0.0.0"}.
  20490. @end deftypevr
  20491. @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv6
  20492. The IPv6 address at which to listen for peer connections, or ``::'' to
  20493. listen at all available IPv6 addresses.
  20494. Defaults to @samp{"::"}.
  20495. @end deftypevr
  20496. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean peer-port-random-on-start?
  20497. If @code{#t}, when the daemon starts it will select a port at random on
  20498. which to listen for peer connections, from the range specified
  20499. (inclusively) by @code{peer-port-random-low} and
  20500. @code{peer-port-random-high}. Otherwise, it listens on the port
  20501. specified by @code{peer-port}.
  20502. Defaults to @samp{#f}.
  20503. @end deftypevr
  20504. @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-low
  20505. The lowest selectable port number when @code{peer-port-random-on-start?}
  20506. is @code{#t}.
  20507. Defaults to @samp{49152}.
  20508. @end deftypevr
  20509. @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-high
  20510. The highest selectable port number when @code{peer-port-random-on-start}
  20511. is @code{#t}.
  20512. Defaults to @samp{65535}.
  20513. @end deftypevr
  20514. @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port
  20515. The port on which to listen for peer connections when
  20516. @code{peer-port-random-on-start?} is @code{#f}.
  20517. Defaults to @samp{51413}.
  20518. @end deftypevr
  20519. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean port-forwarding-enabled?
  20520. If @code{#t}, the daemon will attempt to configure port-forwarding on an
  20521. upstream gateway automatically using @acronym{UPnP} and
  20522. @acronym{NAT-PMP}.
  20523. Defaults to @samp{#t}.
  20524. @end deftypevr
  20525. @deftypevr {@code{transmission-daemon-configuration} parameter} encryption-mode encryption
  20526. The encryption preference for peer connections, one of
  20527. @code{prefer-unencrypted-connections},
  20528. @code{prefer-encrypted-connections} or
  20529. @code{require-encrypted-connections}.
  20530. Defaults to @samp{prefer-encrypted-connections}.
  20531. @end deftypevr
  20532. @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string peer-congestion-algorithm
  20533. The TCP congestion-control algorithm to use for peer connections,
  20534. specified using a string recognized by the operating system in calls to
  20535. @code{setsockopt} (or set to @code{disabled}, in which case the
  20536. operating-system default is used).
  20537. Note that on GNU/Linux systems, the kernel must be configured to allow
  20538. processes to use a congestion-control algorithm not in the default set;
  20539. otherwise, it will deny these requests with ``Operation not permitted''.
  20540. To see which algorithms are available on your system and which are
  20541. currently permitted for use, look at the contents of the files
  20542. @file{tcp_available_congestion_control} and
  20543. @file{tcp_allowed_congestion_control} in the @file{/proc/sys/net/ipv4}
  20544. directory.
  20545. As an example, to have Transmission Daemon use
  20546. @uref{http://www-ece.rice.edu/networks/TCP-LP/,the TCP Low Priority
  20547. congestion-control algorithm}, you'll need to modify your kernel
  20548. configuration to build in support for the algorithm, then update your
  20549. operating-system configuration to allow its use by adding a
  20550. @code{sysctl-service-type} service (or updating the existing one's
  20551. configuration) with lines like the following:
  20552. @lisp
  20553. (service sysctl-service-type
  20554. (sysctl-configuration
  20555. (settings
  20556. ("net.ipv4.tcp_allowed_congestion_control" .
  20557. "reno cubic lp"))))
  20558. @end lisp
  20559. The Transmission Daemon configuration can then be updated with
  20560. @lisp
  20561. (peer-congestion-algorithm "lp")
  20562. @end lisp
  20563. and the system reconfigured to have the changes take effect.
  20564. Defaults to @samp{disabled}.
  20565. @end deftypevr
  20566. @deftypevr {@code{transmission-daemon-configuration} parameter} tcp-type-of-service peer-socket-tos
  20567. The type of service to request in outgoing @acronym{TCP} packets, one of
  20568. @code{default}, @code{low-cost}, @code{throughput}, @code{low-delay} and
  20569. @code{reliability}.
  20570. Defaults to @samp{default}.
  20571. @end deftypevr
  20572. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-global
  20573. The global limit on the number of connected peers.
  20574. Defaults to @samp{200}.
  20575. @end deftypevr
  20576. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-per-torrent
  20577. The per-torrent limit on the number of connected peers.
  20578. Defaults to @samp{50}.
  20579. @end deftypevr
  20580. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer upload-slots-per-torrent
  20581. The maximum number of peers to which the daemon will upload data
  20582. simultaneously for each torrent.
  20583. Defaults to @samp{14}.
  20584. @end deftypevr
  20585. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-id-ttl-hours
  20586. The maximum lifespan, in hours, of the peer ID associated with each
  20587. public torrent before it is regenerated.
  20588. Defaults to @samp{6}.
  20589. @end deftypevr
  20590. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean blocklist-enabled?
  20591. When @code{#t}, the daemon will ignore peers mentioned in the blocklist
  20592. it has most recently downloaded from @code{blocklist-url}.
  20593. Defaults to @samp{#f}.
  20594. @end deftypevr
  20595. @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string blocklist-url
  20596. The URL of a peer blocklist (in @acronym{P2P}-plaintext or eMule
  20597. @file{.dat} format) to be periodically downloaded and applied when
  20598. @code{blocklist-enabled?} is @code{#t}.
  20599. Defaults to @samp{disabled}.
  20600. @end deftypevr
  20601. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean download-queue-enabled?
  20602. If @code{#t}, the daemon will be limited to downloading at most
  20603. @code{download-queue-size} non-stalled torrents simultaneously.
  20604. Defaults to @samp{#t}.
  20605. @end deftypevr
  20606. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer download-queue-size
  20607. The size of the daemon's download queue, which limits the number of
  20608. non-stalled torrents it will download at any one time when
  20609. @code{download-queue-enabled?} is @code{#t}.
  20610. Defaults to @samp{5}.
  20611. @end deftypevr
  20612. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean seed-queue-enabled?
  20613. If @code{#t}, the daemon will be limited to seeding at most
  20614. @code{seed-queue-size} non-stalled torrents simultaneously.
  20615. Defaults to @samp{#f}.
  20616. @end deftypevr
  20617. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer seed-queue-size
  20618. The size of the daemon's seed queue, which limits the number of
  20619. non-stalled torrents it will seed at any one time when
  20620. @code{seed-queue-enabled?} is @code{#t}.
  20621. Defaults to @samp{10}.
  20622. @end deftypevr
  20623. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean queue-stalled-enabled?
  20624. When @code{#t}, the daemon will consider torrents for which it has not
  20625. shared data in the past @code{queue-stalled-minutes} minutes to be
  20626. stalled and not count them against its @code{download-queue-size} and
  20627. @code{seed-queue-size} limits.
  20628. Defaults to @samp{#t}.
  20629. @end deftypevr
  20630. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer queue-stalled-minutes
  20631. The maximum period, in minutes, a torrent may be idle before it is
  20632. considered to be stalled, when @code{queue-stalled-enabled?} is
  20633. @code{#t}.
  20634. Defaults to @samp{30}.
  20635. @end deftypevr
  20636. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean ratio-limit-enabled?
  20637. When @code{#t}, a torrent being seeded will automatically be paused once
  20638. it reaches the ratio specified by @code{ratio-limit}.
  20639. Defaults to @samp{#f}.
  20640. @end deftypevr
  20641. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-rational ratio-limit
  20642. The ratio at which a torrent being seeded will be paused, when
  20643. @code{ratio-limit-enabled?} is @code{#t}.
  20644. Defaults to @samp{2.0}.
  20645. @end deftypevr
  20646. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean idle-seeding-limit-enabled?
  20647. When @code{#t}, a torrent being seeded will automatically be paused once
  20648. it has been idle for @code{idle-seeding-limit} minutes.
  20649. Defaults to @samp{#f}.
  20650. @end deftypevr
  20651. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer idle-seeding-limit
  20652. The maximum period, in minutes, a torrent being seeded may be idle
  20653. before it is paused, when @code{idle-seeding-limit-enabled?} is
  20654. @code{#t}.
  20655. Defaults to @samp{30}.
  20656. @end deftypevr
  20657. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean dht-enabled?
  20658. Enable @uref{http://bittorrent.org/beps/bep_0005.html,the distributed
  20659. hash table (@acronym{DHT}) protocol}, which supports the use of
  20660. trackerless torrents.
  20661. Defaults to @samp{#t}.
  20662. @end deftypevr
  20663. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean lpd-enabled?
  20664. Enable @uref{https://en.wikipedia.org/wiki/Local_Peer_Discovery,local
  20665. peer discovery} (@acronym{LPD}), which allows the discovery of peers on
  20666. the local network and may reduce the amount of data sent over the public
  20667. Internet.
  20668. Defaults to @samp{#f}.
  20669. @end deftypevr
  20670. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean pex-enabled?
  20671. Enable @uref{https://en.wikipedia.org/wiki/Peer_exchange,peer exchange}
  20672. (@acronym{PEX}), which reduces the daemon's reliance on external
  20673. trackers and may improve its performance.
  20674. Defaults to @samp{#t}.
  20675. @end deftypevr
  20676. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean utp-enabled?
  20677. Enable @uref{http://bittorrent.org/beps/bep_0029.html,the micro
  20678. transport protocol} (@acronym{uTP}), which aims to reduce the impact of
  20679. BitTorrent traffic on other users of the local network while maintaining
  20680. full utilization of the available bandwidth.
  20681. Defaults to @samp{#t}.
  20682. @end deftypevr
  20683. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-enabled?
  20684. If @code{#t}, enable the remote procedure call (@acronym{RPC})
  20685. interface, which allows remote control of the daemon via its Web
  20686. interface, the @command{transmission-remote} command-line client, and
  20687. similar tools.
  20688. Defaults to @samp{#t}.
  20689. @end deftypevr
  20690. @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-bind-address
  20691. The IP address at which to listen for @acronym{RPC} connections, or
  20692. ``0.0.0.0'' to listen at all available IP addresses.
  20693. Defaults to @samp{"0.0.0.0"}.
  20694. @end deftypevr
  20695. @deftypevr {@code{transmission-daemon-configuration} parameter} port-number rpc-port
  20696. The port on which to listen for @acronym{RPC} connections.
  20697. Defaults to @samp{9091}.
  20698. @end deftypevr
  20699. @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-url
  20700. The path prefix to use in the @acronym{RPC}-endpoint @acronym{URL}.
  20701. Defaults to @samp{"/transmission/"}.
  20702. @end deftypevr
  20703. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-authentication-required?
  20704. When @code{#t}, clients must authenticate (see @code{rpc-username} and
  20705. @code{rpc-password}) when using the @acronym{RPC} interface. Note this
  20706. has the side effect of disabling host-name whitelisting (see
  20707. @code{rpc-host-whitelist-enabled?}.
  20708. Defaults to @samp{#f}.
  20709. @end deftypevr
  20710. @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string rpc-username
  20711. The username required by clients to access the @acronym{RPC} interface
  20712. when @code{rpc-authentication-required?} is @code{#t}.
  20713. Defaults to @samp{disabled}.
  20714. @end deftypevr
  20715. @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-transmission-password-hash rpc-password
  20716. The password required by clients to access the @acronym{RPC} interface
  20717. when @code{rpc-authentication-required?} is @code{#t}. This must be
  20718. specified using a password hash in the format recognized by Transmission
  20719. clients, either copied from an existing @file{settings.json} file or
  20720. generated using the @code{transmission-password-hash} procedure.
  20721. Defaults to @samp{disabled}.
  20722. @end deftypevr
  20723. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-whitelist-enabled?
  20724. When @code{#t}, @acronym{RPC} requests will be accepted only when they
  20725. originate from an address specified in @code{rpc-whitelist}.
  20726. Defaults to @samp{#t}.
  20727. @end deftypevr
  20728. @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-whitelist
  20729. The list of IP and IPv6 addresses from which @acronym{RPC} requests will
  20730. be accepted when @code{rpc-whitelist-enabled?} is @code{#t}. Wildcards
  20731. may be specified using @samp{*}.
  20732. Defaults to @samp{("127.0.0.1" "::1")}.
  20733. @end deftypevr
  20734. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-host-whitelist-enabled?
  20735. When @code{#t}, @acronym{RPC} requests will be accepted only when they
  20736. are addressed to a host named in @code{rpc-host-whitelist}. Note that
  20737. requests to ``localhost'' or ``localhost.'', or to a numeric address,
  20738. are always accepted regardless of these settings.
  20739. Note also this functionality is disabled when
  20740. @code{rpc-authentication-required?} is @code{#t}.
  20741. Defaults to @samp{#t}.
  20742. @end deftypevr
  20743. @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-host-whitelist
  20744. The list of host names recognized by the @acronym{RPC} server when
  20745. @code{rpc-host-whitelist-enabled?} is @code{#t}.
  20746. Defaults to @samp{()}.
  20747. @end deftypevr
  20748. @deftypevr {@code{transmission-daemon-configuration} parameter} message-level message-level
  20749. The minimum severity level of messages to be logged (to
  20750. @file{/var/log/transmission.log}) by the daemon, one of @code{none} (no
  20751. logging), @code{error}, @code{info} and @code{debug}.
  20752. Defaults to @samp{info}.
  20753. @end deftypevr
  20754. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean start-added-torrents?
  20755. When @code{#t}, torrents are started as soon as they are added;
  20756. otherwise, they are added in ``paused'' state.
  20757. Defaults to @samp{#t}.
  20758. @end deftypevr
  20759. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean script-torrent-done-enabled?
  20760. When @code{#t}, the script specified by
  20761. @code{script-torrent-done-filename} will be invoked each time a torrent
  20762. completes.
  20763. Defaults to @samp{#f}.
  20764. @end deftypevr
  20765. @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-file-object script-torrent-done-filename
  20766. A file name or file-like object specifying a script to run each time a
  20767. torrent completes, when @code{script-torrent-done-enabled?} is
  20768. @code{#t}.
  20769. Defaults to @samp{disabled}.
  20770. @end deftypevr
  20771. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean scrape-paused-torrents-enabled?
  20772. When @code{#t}, the daemon will scrape trackers for a torrent even when
  20773. the torrent is paused.
  20774. Defaults to @samp{#t}.
  20775. @end deftypevr
  20776. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer cache-size-mb
  20777. The amount of memory, in megabytes, to allocate for the daemon's
  20778. in-memory cache. A larger value may increase performance by reducing
  20779. the frequency of disk I/O.
  20780. Defaults to @samp{4}.
  20781. @end deftypevr
  20782. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean prefetch-enabled?
  20783. When @code{#t}, the daemon will try to improve I/O performance by
  20784. hinting to the operating system which data is likely to be read next
  20785. from disk to satisfy requests from peers.
  20786. Defaults to @samp{#t}.
  20787. @end deftypevr
  20788. @c %end of fragment
  20789. @node Monitoring Services
  20790. @subsection Monitoring Services
  20791. @subsubheading Tailon Service
  20792. @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
  20793. viewing and searching log files.
  20794. The following example will configure the service with default values.
  20795. By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
  20796. @lisp
  20797. (service tailon-service-type)
  20798. @end lisp
  20799. The following example customises more of the Tailon configuration,
  20800. adding @command{sed} to the list of allowed commands.
  20801. @lisp
  20802. (service tailon-service-type
  20803. (tailon-configuration
  20804. (config-file
  20805. (tailon-configuration-file
  20806. (allowed-commands '("tail" "grep" "awk" "sed"))))))
  20807. @end lisp
  20808. @deftp {Data Type} tailon-configuration
  20809. Data type representing the configuration of Tailon.
  20810. This type has the following parameters:
  20811. @table @asis
  20812. @item @code{config-file} (default: @code{(tailon-configuration-file)})
  20813. The configuration file to use for Tailon. This can be set to a
  20814. @dfn{tailon-configuration-file} record value, or any gexp
  20815. (@pxref{G-Expressions}).
  20816. For example, to instead use a local file, the @code{local-file} function
  20817. can be used:
  20818. @lisp
  20819. (service tailon-service-type
  20820. (tailon-configuration
  20821. (config-file (local-file "./my-tailon.conf"))))
  20822. @end lisp
  20823. @item @code{package} (default: @code{tailon})
  20824. The tailon package to use.
  20825. @end table
  20826. @end deftp
  20827. @deftp {Data Type} tailon-configuration-file
  20828. Data type representing the configuration options for Tailon.
  20829. This type has the following parameters:
  20830. @table @asis
  20831. @item @code{files} (default: @code{(list "/var/log")})
  20832. List of files to display. The list can include strings for a single file
  20833. or directory, or a list, where the first item is the name of a
  20834. subsection, and the remaining items are the files or directories in that
  20835. subsection.
  20836. @item @code{bind} (default: @code{"localhost:8080"})
  20837. Address and port to which Tailon should bind on.
  20838. @item @code{relative-root} (default: @code{#f})
  20839. URL path to use for Tailon, set to @code{#f} to not use a path.
  20840. @item @code{allow-transfers?} (default: @code{#t})
  20841. Allow downloading the log files in the web interface.
  20842. @item @code{follow-names?} (default: @code{#t})
  20843. Allow tailing of not-yet existent files.
  20844. @item @code{tail-lines} (default: @code{200})
  20845. Number of lines to read initially from each file.
  20846. @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
  20847. Commands to allow running. By default, @code{sed} is disabled.
  20848. @item @code{debug?} (default: @code{#f})
  20849. Set @code{debug?} to @code{#t} to show debug messages.
  20850. @item @code{wrap-lines} (default: @code{#t})
  20851. Initial line wrapping state in the web interface. Set to @code{#t} to
  20852. initially wrap lines (the default), or to @code{#f} to initially not
  20853. wrap lines.
  20854. @item @code{http-auth} (default: @code{#f})
  20855. HTTP authentication type to use. Set to @code{#f} to disable
  20856. authentication (the default). Supported values are @code{"digest"} or
  20857. @code{"basic"}.
  20858. @item @code{users} (default: @code{#f})
  20859. If HTTP authentication is enabled (see @code{http-auth}), access will be
  20860. restricted to the credentials provided here. To configure users, use a
  20861. list of pairs, where the first element of the pair is the username, and
  20862. the 2nd element of the pair is the password.
  20863. @lisp
  20864. (tailon-configuration-file
  20865. (http-auth "basic")
  20866. (users '(("user1" . "password1")
  20867. ("user2" . "password2"))))
  20868. @end lisp
  20869. @end table
  20870. @end deftp
  20871. @subsubheading Darkstat Service
  20872. @cindex darkstat
  20873. Darkstat is a packet sniffer that captures network traffic, calculates
  20874. statistics about usage, and serves reports over HTTP.
  20875. @defvar {Scheme Variable} darkstat-service-type
  20876. This is the service type for the
  20877. @uref{https://unix4lyfe.org/darkstat/, darkstat}
  20878. service, its value must be a @code{darkstat-configuration} record as in
  20879. this example:
  20880. @lisp
  20881. (service darkstat-service-type
  20882. (darkstat-configuration
  20883. (interface "eno1")))
  20884. @end lisp
  20885. @end defvar
  20886. @deftp {Data Type} darkstat-configuration
  20887. Data type representing the configuration of @command{darkstat}.
  20888. @table @asis
  20889. @item @code{package} (default: @code{darkstat})
  20890. The darkstat package to use.
  20891. @item @code{interface}
  20892. Capture traffic on the specified network interface.
  20893. @item @code{port} (default: @code{"667"})
  20894. Bind the web interface to the specified port.
  20895. @item @code{bind-address} (default: @code{"127.0.0.1"})
  20896. Bind the web interface to the specified address.
  20897. @item @code{base} (default: @code{"/"})
  20898. Specify the path of the base URL@. This can be useful if
  20899. @command{darkstat} is accessed via a reverse proxy.
  20900. @end table
  20901. @end deftp
  20902. @anchor{prometheus-node-exporter}
  20903. @subsubheading Prometheus Node Exporter Service
  20904. @cindex prometheus-node-exporter
  20905. The Prometheus ``node exporter'' makes hardware and operating system statistics
  20906. provided by the Linux kernel available for the Prometheus monitoring system.
  20907. This service should be deployed on all physical nodes and virtual machines,
  20908. where monitoring these statistics is desirable.
  20909. @defvar {Scheme variable} prometheus-node-exporter-service-type
  20910. This is the service type for the
  20911. @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
  20912. service, its value must be a @code{prometheus-node-exporter-configuration}.
  20913. @lisp
  20914. (service prometheus-node-exporter-service-type)
  20915. @end lisp
  20916. @end defvar
  20917. @deftp {Data Type} prometheus-node-exporter-configuration
  20918. Data type representing the configuration of @command{node_exporter}.
  20919. @table @asis
  20920. @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
  20921. The prometheus-node-exporter package to use.
  20922. @item @code{web-listen-address} (default: @code{":9100"})
  20923. Bind the web interface to the specified address.
  20924. @item @code{textfile-directory} (default: @code{"/var/lib/prometheus/node-exporter"})
  20925. This directory can be used to export metrics specific to this machine.
  20926. Files containing metrics in the text format, with the filename ending in
  20927. @code{.prom} should be placed in this directory.
  20928. @item @code{extra-options} (default: @code{'()})
  20929. Extra options to pass to the Prometheus node exporter.
  20930. @end table
  20931. @end deftp
  20932. @subsubheading Zabbix server
  20933. @cindex zabbix zabbix-server
  20934. Zabbix is a high performance monitoring system that can collect data from a
  20935. variety of sources and provide the results in a web-based interface. Alerting
  20936. and reporting is built-in, as well as @dfn{templates} for common operating
  20937. system metrics such as network utilization, CPU load, and disk space consumption.
  20938. This service provides the central Zabbix monitoring service; you also need
  20939. @ref{zabbix-front-end,@code{zabbix-front-end-service-type}} to configure Zabbix
  20940. and display results, and optionally @ref{zabbix-agent,
  20941. @code{zabbix-agent-service-type}} on machines that should be monitored (other
  20942. data sources are supported, such as @ref{prometheus-node-exporter,
  20943. Prometheus Node Exporter}).
  20944. @defvar {Scheme variable} zabbix-server-service-type
  20945. This is the service type for the Zabbix server service. Its value must be a
  20946. @code{zabbix-server-configuration} record, shown below.
  20947. @end defvar
  20948. @c %start of fragment
  20949. @deftp {Data Type} zabbix-server-configuration
  20950. Available @code{zabbix-server-configuration} fields are:
  20951. @table @asis
  20952. @item @code{zabbix-server} (default: @code{zabbix-server}) (type: file-like)
  20953. The zabbix-server package.
  20954. @item @code{user} (default: @code{"zabbix"}) (type: string)
  20955. User who will run the Zabbix server.
  20956. @item @code{group} (default: @code{"zabbix"}) (type: group)
  20957. Group who will run the Zabbix server.
  20958. @item @code{db-host} (default: @code{"127.0.0.1"}) (type: string)
  20959. Database host name.
  20960. @item @code{db-name} (default: @code{"zabbix"}) (type: string)
  20961. Database name.
  20962. @item @code{db-user} (default: @code{"zabbix"}) (type: string)
  20963. Database user.
  20964. @item @code{db-password} (default: @code{""}) (type: string)
  20965. Database password. Please, use @code{include-files} with
  20966. @code{DBPassword=SECRET} inside a specified file instead.
  20967. @item @code{db-port} (default: @code{5432}) (type: number)
  20968. Database port.
  20969. @item @code{log-type} (default: @code{""}) (type: string)
  20970. Specifies where log messages are written to:
  20971. @itemize @bullet
  20972. @item @code{system} - syslog.
  20973. @item @code{file} - file specified with @code{log-file} parameter.
  20974. @item @code{console} - standard output.
  20975. @end itemize
  20976. @item @code{log-file} (default: @code{"/var/log/zabbix/server.log"}) (type: string)
  20977. Log file name for @code{log-type} @code{file} parameter.
  20978. @item @code{pid-file} (default: @code{"/var/run/zabbix/zabbix_server.pid"}) (type: string)
  20979. Name of PID file.
  20980. @item @code{ssl-ca-location} (default: @code{"/etc/ssl/certs/ca-certificates.crt"}) (type: string)
  20981. The location of certificate authority (CA) files for SSL server
  20982. certificate verification.
  20983. @item @code{ssl-cert-location} (default: @code{"/etc/ssl/certs"}) (type: string)
  20984. Location of SSL client certificates.
  20985. @item @code{extra-options} (default: @code{""}) (type: extra-options)
  20986. Extra options will be appended to Zabbix server configuration file.
  20987. @item @code{include-files} (default: @code{()}) (type: include-files)
  20988. You may include individual files or all files in a directory in the
  20989. configuration file.
  20990. @end table
  20991. @end deftp
  20992. @c %end of fragment
  20993. @anchor{zabbix-agent}
  20994. @subsubheading Zabbix agent
  20995. @cindex zabbix zabbix-agent
  20996. The Zabbix agent gathers information about the running system for the Zabbix
  20997. monitoring server. It has a variety of built-in checks, and can be extended
  20998. with custom
  20999. @uref{https://www.zabbix.com/documentation/current/en/manual/config/items/userparameters,
  21000. @dfn{user parameters}}.
  21001. @defvar {Scheme variable} zabbix-agent-service-type
  21002. This is the service type for the Zabbix agent service. Its value must be a
  21003. @code{zabbix-agent-configuration} record, shown below.
  21004. @end defvar
  21005. @c %start of fragment
  21006. @deftp {Data Type} zabbix-agent-configuration
  21007. Available @code{zabbix-agent-configuration} fields are:
  21008. @table @asis
  21009. @item @code{zabbix-agent} (default: @code{zabbix-agentd}) (type: file-like)
  21010. The zabbix-agent package.
  21011. @item @code{user} (default: @code{"zabbix"}) (type: string)
  21012. User who will run the Zabbix agent.
  21013. @item @code{group} (default: @code{"zabbix"}) (type: group)
  21014. Group who will run the Zabbix agent.
  21015. @item @code{hostname} (default: @code{""}) (type: string)
  21016. Unique, case sensitive hostname which is required for active checks and
  21017. must match hostname as configured on the server.
  21018. @item @code{log-type} (default: @code{""}) (type: string)
  21019. Specifies where log messages are written to:
  21020. @itemize @bullet
  21021. @item
  21022. @code{system} - syslog.
  21023. @item @code{file} - file specified with
  21024. @code{log-file} parameter.
  21025. @item @code{console} - standard output.
  21026. @end itemize
  21027. @item @code{log-file} (default: @code{"/var/log/zabbix/agent.log"}) (type: string)
  21028. Log file name for @code{log-type} @code{file} parameter.
  21029. @item @code{pid-file} (default: @code{"/var/run/zabbix/zabbix_agent.pid"}) (type: string)
  21030. Name of PID file.
  21031. @item @code{server} (default: @code{("127.0.0.1")}) (type: list)
  21032. List of IP addresses, optionally in CIDR notation, or hostnames of
  21033. Zabbix servers and Zabbix proxies. Incoming connections will be
  21034. accepted only from the hosts listed here.
  21035. @item @code{server-active} (default: @code{("127.0.0.1")}) (type: list)
  21036. List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
  21037. proxies for active checks. If port is not specified, default port is
  21038. used. If this parameter is not specified, active checks are disabled.
  21039. @item @code{extra-options} (default: @code{""}) (type: extra-options)
  21040. Extra options will be appended to Zabbix server configuration file.
  21041. @item @code{include-files} (default: @code{()}) (type: include-files)
  21042. You may include individual files or all files in a directory in the
  21043. configuration file.
  21044. @end table
  21045. @end deftp
  21046. @c %end of fragment
  21047. @anchor{zabbix-front-end}
  21048. @subsubheading Zabbix front-end
  21049. @cindex zabbix zabbix-front-end
  21050. The Zabbix front-end provides a web interface to Zabbix. It does not need
  21051. to run on the same machine as the Zabbix server. This service works by
  21052. extending the @ref{PHP-FPM} and @ref{NGINX} services with the configuration
  21053. necessary for loading the Zabbix user interface.
  21054. @defvar {Scheme variable} zabbix-front-end-service-type
  21055. This is the service type for the Zabbix web frontend. Its value must be a
  21056. @code{zabbix-front-end-configuration} record, shown below.
  21057. @end defvar
  21058. @c %start of fragment
  21059. @deftp {Data Type} zabbix-front-end-configuration
  21060. Available @code{zabbix-front-end-configuration} fields are:
  21061. @table @asis
  21062. @item @code{zabbix-server} (default: @code{zabbix-server}) (type: file-like)
  21063. The Zabbix server package to use.
  21064. @item @code{nginx} (default: @code{()}) (type: list)
  21065. List of @ref{nginx-server-configuration,@code{nginx-server-configuration}}
  21066. blocks for the Zabbix front-end. When empty, a default that listens on
  21067. port 80 is used.
  21068. @item @code{db-host} (default: @code{"localhost"}) (type: string)
  21069. Database host name.
  21070. @item @code{db-port} (default: @code{5432}) (type: number)
  21071. Database port.
  21072. @item @code{db-name} (default: @code{"zabbix"}) (type: string)
  21073. Database name.
  21074. @item @code{db-user} (default: @code{"zabbix"}) (type: string)
  21075. Database user.
  21076. @item @code{db-password} (default: @code{""}) (type: string)
  21077. Database password. Please, use @code{db-secret-file} instead.
  21078. @item @code{db-secret-file} (default: @code{""}) (type: string)
  21079. Secret file which will be appended to @file{zabbix.conf.php} file. This
  21080. file contains credentials for use by Zabbix front-end. You are expected
  21081. to create it manually.
  21082. @item @code{zabbix-host} (default: @code{"localhost"}) (type: string)
  21083. Zabbix server hostname.
  21084. @item @code{zabbix-port} (default: @code{10051}) (type: number)
  21085. Zabbix server port.
  21086. @end table
  21087. @end deftp
  21088. @c %end of fragment
  21089. @node Kerberos Services
  21090. @subsection Kerberos Services
  21091. @cindex Kerberos
  21092. The @code{(gnu services kerberos)} module provides services relating to
  21093. the authentication protocol @dfn{Kerberos}.
  21094. @subsubheading Krb5 Service
  21095. Programs using a Kerberos client library normally
  21096. expect a configuration file in @file{/etc/krb5.conf}.
  21097. This service generates such a file from a definition provided in the
  21098. operating system declaration.
  21099. It does not cause any daemon to be started.
  21100. No ``keytab'' files are provided by this service---you must explicitly create them.
  21101. This service is known to work with the MIT client library, @code{mit-krb5}.
  21102. Other implementations have not been tested.
  21103. @defvr {Scheme Variable} krb5-service-type
  21104. A service type for Kerberos 5 clients.
  21105. @end defvr
  21106. @noindent
  21107. Here is an example of its use:
  21108. @lisp
  21109. (service krb5-service-type
  21110. (krb5-configuration
  21111. (default-realm "EXAMPLE.COM")
  21112. (allow-weak-crypto? #t)
  21113. (realms (list
  21114. (krb5-realm
  21115. (name "EXAMPLE.COM")
  21116. (admin-server "groucho.example.com")
  21117. (kdc "karl.example.com"))
  21118. (krb5-realm
  21119. (name "ARGRX.EDU")
  21120. (admin-server "kerb-admin.argrx.edu")
  21121. (kdc "keys.argrx.edu"))))))
  21122. @end lisp
  21123. @noindent
  21124. This example provides a Kerberos@tie{}5 client configuration which:
  21125. @itemize
  21126. @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
  21127. of which have distinct administration servers and key distribution centers;
  21128. @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
  21129. specified by clients;
  21130. @item Accepts services which only support encryption types known to be weak.
  21131. @end itemize
  21132. The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
  21133. Only the most commonly used ones are described here.
  21134. For a full list, and more detailed explanation of each, see the MIT
  21135. @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
  21136. documentation.
  21137. @deftp {Data Type} krb5-realm
  21138. @cindex realm, kerberos
  21139. @table @asis
  21140. @item @code{name}
  21141. This field is a string identifying the name of the realm.
  21142. A common convention is to use the fully qualified DNS name of your organization,
  21143. converted to upper case.
  21144. @item @code{admin-server}
  21145. This field is a string identifying the host where the administration server is
  21146. running.
  21147. @item @code{kdc}
  21148. This field is a string identifying the key distribution center
  21149. for the realm.
  21150. @end table
  21151. @end deftp
  21152. @deftp {Data Type} krb5-configuration
  21153. @table @asis
  21154. @item @code{allow-weak-crypto?} (default: @code{#f})
  21155. If this flag is @code{#t} then services which only offer encryption algorithms
  21156. known to be weak will be accepted.
  21157. @item @code{default-realm} (default: @code{#f})
  21158. This field should be a string identifying the default Kerberos
  21159. realm for the client.
  21160. You should set this field to the name of your Kerberos realm.
  21161. If this value is @code{#f}
  21162. then a realm must be specified with every Kerberos principal when invoking programs
  21163. such as @command{kinit}.
  21164. @item @code{realms}
  21165. This should be a non-empty list of @code{krb5-realm} objects, which clients may
  21166. access.
  21167. Normally, one of them will have a @code{name} field matching the @code{default-realm}
  21168. field.
  21169. @end table
  21170. @end deftp
  21171. @subsubheading PAM krb5 Service
  21172. @cindex pam-krb5
  21173. The @code{pam-krb5} service allows for login authentication and password
  21174. management via Kerberos.
  21175. You will need this service if you want PAM enabled applications to authenticate
  21176. users using Kerberos.
  21177. @defvr {Scheme Variable} pam-krb5-service-type
  21178. A service type for the Kerberos 5 PAM module.
  21179. @end defvr
  21180. @deftp {Data Type} pam-krb5-configuration
  21181. Data type representing the configuration of the Kerberos 5 PAM module.
  21182. This type has the following parameters:
  21183. @table @asis
  21184. @item @code{pam-krb5} (default: @code{pam-krb5})
  21185. The pam-krb5 package to use.
  21186. @item @code{minimum-uid} (default: @code{1000})
  21187. The smallest user ID for which Kerberos authentications should be attempted.
  21188. Local accounts with lower values will silently fail to authenticate.
  21189. @end table
  21190. @end deftp
  21191. @node LDAP Services
  21192. @subsection LDAP Services
  21193. @cindex LDAP
  21194. @cindex nslcd, LDAP service
  21195. The @code{(gnu services authentication)} module provides the
  21196. @code{nslcd-service-type}, which can be used to authenticate against an LDAP
  21197. server. In addition to configuring the service itself, you may want to add
  21198. @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
  21199. Switch} for detailed information.
  21200. Here is a simple operating system declaration with a default configuration of
  21201. the @code{nslcd-service-type} and a Name Service Switch configuration that
  21202. consults the @code{ldap} name service last:
  21203. @lisp
  21204. (use-service-modules authentication)
  21205. (use-modules (gnu system nss))
  21206. ...
  21207. (operating-system
  21208. ...
  21209. (services
  21210. (cons*
  21211. (service nslcd-service-type)
  21212. (service dhcp-client-service-type)
  21213. %base-services))
  21214. (name-service-switch
  21215. (let ((services (list (name-service (name "db"))
  21216. (name-service (name "files"))
  21217. (name-service (name "ldap")))))
  21218. (name-service-switch
  21219. (inherit %mdns-host-lookup-nss)
  21220. (password services)
  21221. (shadow services)
  21222. (group services)
  21223. (netgroup services)
  21224. (gshadow services)))))
  21225. @end lisp
  21226. @c %start of generated documentation for nslcd-configuration
  21227. Available @code{nslcd-configuration} fields are:
  21228. @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
  21229. The @code{nss-pam-ldapd} package to use.
  21230. @end deftypevr
  21231. @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
  21232. The number of threads to start that can handle requests and perform LDAP
  21233. queries. Each thread opens a separate connection to the LDAP server.
  21234. The default is to start 5 threads.
  21235. Defaults to @samp{disabled}.
  21236. @end deftypevr
  21237. @deftypevr {@code{nslcd-configuration} parameter} string uid
  21238. This specifies the user id with which the daemon should be run.
  21239. Defaults to @samp{"nslcd"}.
  21240. @end deftypevr
  21241. @deftypevr {@code{nslcd-configuration} parameter} string gid
  21242. This specifies the group id with which the daemon should be run.
  21243. Defaults to @samp{"nslcd"}.
  21244. @end deftypevr
  21245. @deftypevr {@code{nslcd-configuration} parameter} log-option log
  21246. This option controls the way logging is done via a list containing
  21247. SCHEME and LEVEL@. The SCHEME argument may either be the symbols
  21248. @samp{none} or @samp{syslog}, or an absolute file name. The LEVEL
  21249. argument is optional and specifies the log level. The log level may be
  21250. one of the following symbols: @samp{crit}, @samp{error}, @samp{warning},
  21251. @samp{notice}, @samp{info} or @samp{debug}. All messages with the
  21252. specified log level or higher are logged.
  21253. Defaults to @samp{("/var/log/nslcd" info)}.
  21254. @end deftypevr
  21255. @deftypevr {@code{nslcd-configuration} parameter} list uri
  21256. The list of LDAP server URIs. Normally, only the first server will be
  21257. used with the following servers as fall-back.
  21258. Defaults to @samp{("ldap://localhost:389/")}.
  21259. @end deftypevr
  21260. @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
  21261. The version of the LDAP protocol to use. The default is to use the
  21262. maximum version supported by the LDAP library.
  21263. Defaults to @samp{disabled}.
  21264. @end deftypevr
  21265. @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
  21266. Specifies the distinguished name with which to bind to the directory
  21267. server for lookups. The default is to bind anonymously.
  21268. Defaults to @samp{disabled}.
  21269. @end deftypevr
  21270. @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
  21271. Specifies the credentials with which to bind. This option is only
  21272. applicable when used with binddn.
  21273. Defaults to @samp{disabled}.
  21274. @end deftypevr
  21275. @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
  21276. Specifies the distinguished name to use when the root user tries to
  21277. modify a user's password using the PAM module.
  21278. Defaults to @samp{disabled}.
  21279. @end deftypevr
  21280. @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
  21281. Specifies the credentials with which to bind if the root user tries to
  21282. change a user's password. This option is only applicable when used with
  21283. rootpwmoddn
  21284. Defaults to @samp{disabled}.
  21285. @end deftypevr
  21286. @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
  21287. Specifies the SASL mechanism to be used when performing SASL
  21288. authentication.
  21289. Defaults to @samp{disabled}.
  21290. @end deftypevr
  21291. @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
  21292. Specifies the SASL realm to be used when performing SASL authentication.
  21293. Defaults to @samp{disabled}.
  21294. @end deftypevr
  21295. @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
  21296. Specifies the authentication identity to be used when performing SASL
  21297. authentication.
  21298. Defaults to @samp{disabled}.
  21299. @end deftypevr
  21300. @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
  21301. Specifies the authorization identity to be used when performing SASL
  21302. authentication.
  21303. Defaults to @samp{disabled}.
  21304. @end deftypevr
  21305. @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
  21306. Determines whether the LDAP server host name should be canonicalised. If
  21307. this is enabled the LDAP library will do a reverse host name lookup. By
  21308. default, it is left up to the LDAP library whether this check is
  21309. performed or not.
  21310. Defaults to @samp{disabled}.
  21311. @end deftypevr
  21312. @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
  21313. Set the name for the GSS-API Kerberos credentials cache.
  21314. Defaults to @samp{disabled}.
  21315. @end deftypevr
  21316. @deftypevr {@code{nslcd-configuration} parameter} string base
  21317. The directory search base.
  21318. Defaults to @samp{"dc=example,dc=com"}.
  21319. @end deftypevr
  21320. @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
  21321. Specifies the search scope (subtree, onelevel, base or children). The
  21322. default scope is subtree; base scope is almost never useful for name
  21323. service lookups; children scope is not supported on all servers.
  21324. Defaults to @samp{(subtree)}.
  21325. @end deftypevr
  21326. @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
  21327. Specifies the policy for dereferencing aliases. The default policy is
  21328. to never dereference aliases.
  21329. Defaults to @samp{disabled}.
  21330. @end deftypevr
  21331. @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
  21332. Specifies whether automatic referral chasing should be enabled. The
  21333. default behaviour is to chase referrals.
  21334. Defaults to @samp{disabled}.
  21335. @end deftypevr
  21336. @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
  21337. This option allows for custom attributes to be looked up instead of the
  21338. default RFC 2307 attributes. It is a list of maps, each consisting of
  21339. the name of a map, the RFC 2307 attribute to match and the query
  21340. expression for the attribute as it is available in the directory.
  21341. Defaults to @samp{()}.
  21342. @end deftypevr
  21343. @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
  21344. A list of filters consisting of the name of a map to which the filter
  21345. applies and an LDAP search filter expression.
  21346. Defaults to @samp{()}.
  21347. @end deftypevr
  21348. @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
  21349. Specifies the time limit in seconds to use when connecting to the
  21350. directory server. The default value is 10 seconds.
  21351. Defaults to @samp{disabled}.
  21352. @end deftypevr
  21353. @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
  21354. Specifies the time limit (in seconds) to wait for a response from the
  21355. LDAP server. A value of zero, which is the default, is to wait
  21356. indefinitely for searches to be completed.
  21357. Defaults to @samp{disabled}.
  21358. @end deftypevr
  21359. @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
  21360. Specifies the period if inactivity (in seconds) after which the con‐
  21361. nection to the LDAP server will be closed. The default is not to time
  21362. out connections.
  21363. Defaults to @samp{disabled}.
  21364. @end deftypevr
  21365. @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
  21366. Specifies the number of seconds to sleep when connecting to all LDAP
  21367. servers fails. By default one second is waited between the first
  21368. failure and the first retry.
  21369. Defaults to @samp{disabled}.
  21370. @end deftypevr
  21371. @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
  21372. Specifies the time after which the LDAP server is considered to be
  21373. permanently unavailable. Once this time is reached retries will be done
  21374. only once per this time period. The default value is 10 seconds.
  21375. Defaults to @samp{disabled}.
  21376. @end deftypevr
  21377. @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
  21378. Specifies whether to use SSL/TLS or not (the default is not to). If
  21379. 'start-tls is specified then StartTLS is used rather than raw LDAP over
  21380. SSL.
  21381. Defaults to @samp{disabled}.
  21382. @end deftypevr
  21383. @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
  21384. Specifies what checks to perform on a server-supplied certificate. The
  21385. meaning of the values is described in the ldap.conf(5) manual page.
  21386. Defaults to @samp{disabled}.
  21387. @end deftypevr
  21388. @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
  21389. Specifies the directory containing X.509 certificates for peer authen‐
  21390. tication. This parameter is ignored when using GnuTLS.
  21391. Defaults to @samp{disabled}.
  21392. @end deftypevr
  21393. @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
  21394. Specifies the path to the X.509 certificate for peer authentication.
  21395. Defaults to @samp{disabled}.
  21396. @end deftypevr
  21397. @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
  21398. Specifies the path to an entropy source. This parameter is ignored when
  21399. using GnuTLS.
  21400. Defaults to @samp{disabled}.
  21401. @end deftypevr
  21402. @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
  21403. Specifies the ciphers to use for TLS as a string.
  21404. Defaults to @samp{disabled}.
  21405. @end deftypevr
  21406. @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
  21407. Specifies the path to the file containing the local certificate for
  21408. client TLS authentication.
  21409. Defaults to @samp{disabled}.
  21410. @end deftypevr
  21411. @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
  21412. Specifies the path to the file containing the private key for client TLS
  21413. authentication.
  21414. Defaults to @samp{disabled}.
  21415. @end deftypevr
  21416. @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
  21417. Set this to a number greater than 0 to request paged results from the
  21418. LDAP server in accordance with RFC2696. The default (0) is to not
  21419. request paged results.
  21420. Defaults to @samp{disabled}.
  21421. @end deftypevr
  21422. @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
  21423. This option prevents group membership lookups through LDAP for the
  21424. specified users. Alternatively, the value 'all-local may be used. With
  21425. that value nslcd builds a full list of non-LDAP users on startup.
  21426. Defaults to @samp{disabled}.
  21427. @end deftypevr
  21428. @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
  21429. This option ensures that LDAP users with a numeric user id lower than
  21430. the specified value are ignored.
  21431. Defaults to @samp{disabled}.
  21432. @end deftypevr
  21433. @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
  21434. This option specifies an offset that is added to all LDAP numeric user
  21435. ids. This can be used to avoid user id collisions with local users.
  21436. Defaults to @samp{disabled}.
  21437. @end deftypevr
  21438. @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
  21439. This option specifies an offset that is added to all LDAP numeric group
  21440. ids. This can be used to avoid user id collisions with local groups.
  21441. Defaults to @samp{disabled}.
  21442. @end deftypevr
  21443. @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
  21444. If this option is set, the member attribute of a group may point to
  21445. another group. Members of nested groups are also returned in the higher
  21446. level group and parent groups are returned when finding groups for a
  21447. specific user. The default is not to perform extra searches for nested
  21448. groups.
  21449. Defaults to @samp{disabled}.
  21450. @end deftypevr
  21451. @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
  21452. If this option is set, the group member list is not retrieved when
  21453. looking up groups. Lookups for finding which groups a user belongs to
  21454. will remain functional so the user will likely still get the correct
  21455. groups assigned on login.
  21456. Defaults to @samp{disabled}.
  21457. @end deftypevr
  21458. @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
  21459. If this option is set, functions which cause all user/group entries to
  21460. be loaded from the directory will not succeed in doing so. This can
  21461. dramatically reduce LDAP server load in situations where there are a
  21462. great number of users and/or groups. This option is not recommended for
  21463. most configurations.
  21464. Defaults to @samp{disabled}.
  21465. @end deftypevr
  21466. @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
  21467. This option can be used to specify how user and group names are verified
  21468. within the system. This pattern is used to check all user and group
  21469. names that are requested and returned from LDAP.
  21470. Defaults to @samp{disabled}.
  21471. @end deftypevr
  21472. @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
  21473. This specifies whether or not to perform searches using case-insensitive
  21474. matching. Enabling this could open up the system to authorization
  21475. bypass vulnerabilities and introduce nscd cache poisoning
  21476. vulnerabilities which allow denial of service.
  21477. Defaults to @samp{disabled}.
  21478. @end deftypevr
  21479. @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
  21480. This option specifies whether password policy controls are requested and
  21481. handled from the LDAP server when performing user authentication.
  21482. Defaults to @samp{disabled}.
  21483. @end deftypevr
  21484. @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
  21485. By default nslcd performs an LDAP search with the user's credentials
  21486. after BIND (authentication) to ensure that the BIND operation was
  21487. successful. The default search is a simple check to see if the user's
  21488. DN exists. A search filter can be specified that will be used instead.
  21489. It should return at least one entry.
  21490. Defaults to @samp{disabled}.
  21491. @end deftypevr
  21492. @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
  21493. This option allows flexible fine tuning of the authorisation check that
  21494. should be performed. The search filter specified is executed and if any
  21495. entries match, access is granted, otherwise access is denied.
  21496. Defaults to @samp{disabled}.
  21497. @end deftypevr
  21498. @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
  21499. If this option is set password modification using pam_ldap will be
  21500. denied and the specified message will be presented to the user instead.
  21501. The message can be used to direct the user to an alternative means of
  21502. changing their password.
  21503. Defaults to @samp{disabled}.
  21504. @end deftypevr
  21505. @deftypevr {@code{nslcd-configuration} parameter} list pam-services
  21506. List of pam service names for which LDAP authentication should suffice.
  21507. Defaults to @samp{()}.
  21508. @end deftypevr
  21509. @c %end of generated documentation for nslcd-configuration
  21510. @node Web Services
  21511. @subsection Web Services
  21512. @cindex web
  21513. @cindex www
  21514. @cindex HTTP
  21515. The @code{(gnu services web)} module provides the Apache HTTP Server,
  21516. the nginx web server, and also a fastcgi wrapper daemon.
  21517. @subsubheading Apache HTTP Server
  21518. @deffn {Scheme Variable} httpd-service-type
  21519. Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
  21520. (@dfn{httpd}). The value for this service type is a
  21521. @code{httpd-configuration} record.
  21522. A simple example configuration is given below.
  21523. @lisp
  21524. (service httpd-service-type
  21525. (httpd-configuration
  21526. (config
  21527. (httpd-config-file
  21528. (server-name "www.example.com")
  21529. (document-root "/srv/http/www.example.com")))))
  21530. @end lisp
  21531. Other services can also extend the @code{httpd-service-type} to add to
  21532. the configuration.
  21533. @lisp
  21534. (simple-service 'www.example.com-server httpd-service-type
  21535. (list
  21536. (httpd-virtualhost
  21537. "*:80"
  21538. (list (string-join '("ServerName www.example.com"
  21539. "DocumentRoot /srv/http/www.example.com")
  21540. "\n")))))
  21541. @end lisp
  21542. @end deffn
  21543. The details for the @code{httpd-configuration}, @code{httpd-module},
  21544. @code{httpd-config-file} and @code{httpd-virtualhost} record types are
  21545. given below.
  21546. @deffn {Data Type} httpd-configuration
  21547. This data type represents the configuration for the httpd service.
  21548. @table @asis
  21549. @item @code{package} (default: @code{httpd})
  21550. The httpd package to use.
  21551. @item @code{pid-file} (default: @code{"/var/run/httpd"})
  21552. The pid file used by the shepherd-service.
  21553. @item @code{config} (default: @code{(httpd-config-file)})
  21554. The configuration file to use with the httpd service. The default value
  21555. is a @code{httpd-config-file} record, but this can also be a different
  21556. G-expression that generates a file, for example a @code{plain-file}. A
  21557. file outside of the store can also be specified through a string.
  21558. @end table
  21559. @end deffn
  21560. @deffn {Data Type} httpd-module
  21561. This data type represents a module for the httpd service.
  21562. @table @asis
  21563. @item @code{name}
  21564. The name of the module.
  21565. @item @code{file}
  21566. The file for the module. This can be relative to the httpd package being
  21567. used, the absolute location of a file, or a G-expression for a file
  21568. within the store, for example @code{(file-append mod-wsgi
  21569. "/modules/mod_wsgi.so")}.
  21570. @end table
  21571. @end deffn
  21572. @defvr {Scheme Variable} %default-httpd-modules
  21573. A default list of @code{httpd-module} objects.
  21574. @end defvr
  21575. @deffn {Data Type} httpd-config-file
  21576. This data type represents a configuration file for the httpd service.
  21577. @table @asis
  21578. @item @code{modules} (default: @code{%default-httpd-modules})
  21579. The modules to load. Additional modules can be added here, or loaded by
  21580. additional configuration.
  21581. For example, in order to handle requests for PHP files, you can use Apache’s
  21582. @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
  21583. @lisp
  21584. (service httpd-service-type
  21585. (httpd-configuration
  21586. (config
  21587. (httpd-config-file
  21588. (modules (cons*
  21589. (httpd-module
  21590. (name "proxy_module")
  21591. (file "modules/mod_proxy.so"))
  21592. (httpd-module
  21593. (name "proxy_fcgi_module")
  21594. (file "modules/mod_proxy_fcgi.so"))
  21595. %default-httpd-modules))
  21596. (extra-config (list "\
  21597. <FilesMatch \\.php$>
  21598. SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
  21599. </FilesMatch>"))))))
  21600. (service php-fpm-service-type
  21601. (php-fpm-configuration
  21602. (socket "/var/run/php-fpm.sock")
  21603. (socket-group "httpd")))
  21604. @end lisp
  21605. @item @code{server-root} (default: @code{httpd})
  21606. The @code{ServerRoot} in the configuration file, defaults to the httpd
  21607. package. Directives including @code{Include} and @code{LoadModule} are
  21608. taken as relative to the server root.
  21609. @item @code{server-name} (default: @code{#f})
  21610. The @code{ServerName} in the configuration file, used to specify the
  21611. request scheme, hostname and port that the server uses to identify
  21612. itself.
  21613. This doesn't need to be set in the server config, and can be specified
  21614. in virtual hosts. The default is @code{#f} to not specify a
  21615. @code{ServerName}.
  21616. @item @code{document-root} (default: @code{"/srv/http"})
  21617. The @code{DocumentRoot} from which files will be served.
  21618. @item @code{listen} (default: @code{'("80")})
  21619. The list of values for the @code{Listen} directives in the config
  21620. file. The value should be a list of strings, when each string can
  21621. specify the port number to listen on, and optionally the IP address and
  21622. protocol to use.
  21623. @item @code{pid-file} (default: @code{"/var/run/httpd"})
  21624. The @code{PidFile} to use. This should match the @code{pid-file} set in
  21625. the @code{httpd-configuration} so that the Shepherd service is
  21626. configured correctly.
  21627. @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
  21628. The @code{ErrorLog} to which the server will log errors.
  21629. @item @code{user} (default: @code{"httpd"})
  21630. The @code{User} which the server will answer requests as.
  21631. @item @code{group} (default: @code{"httpd"})
  21632. The @code{Group} which the server will answer requests as.
  21633. @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
  21634. A flat list of strings and G-expressions which will be added to the end
  21635. of the configuration file.
  21636. Any values which the service is extended with will be appended to this
  21637. list.
  21638. @end table
  21639. @end deffn
  21640. @deffn {Data Type} httpd-virtualhost
  21641. This data type represents a virtualhost configuration block for the httpd service.
  21642. These should be added to the extra-config for the httpd-service.
  21643. @lisp
  21644. (simple-service 'www.example.com-server httpd-service-type
  21645. (list
  21646. (httpd-virtualhost
  21647. "*:80"
  21648. (list (string-join '("ServerName www.example.com"
  21649. "DocumentRoot /srv/http/www.example.com")
  21650. "\n")))))
  21651. @end lisp
  21652. @table @asis
  21653. @item @code{addresses-and-ports}
  21654. The addresses and ports for the @code{VirtualHost} directive.
  21655. @item @code{contents}
  21656. The contents of the @code{VirtualHost} directive, this should be a list
  21657. of strings and G-expressions.
  21658. @end table
  21659. @end deffn
  21660. @anchor{NGINX}
  21661. @subsubheading NGINX
  21662. @deffn {Scheme Variable} nginx-service-type
  21663. Service type for the @uref{https://nginx.org/,NGinx} web server. The
  21664. value for this service type is a @code{<nginx-configuration>} record.
  21665. A simple example configuration is given below.
  21666. @lisp
  21667. (service nginx-service-type
  21668. (nginx-configuration
  21669. (server-blocks
  21670. (list (nginx-server-configuration
  21671. (server-name '("www.example.com"))
  21672. (root "/srv/http/www.example.com"))))))
  21673. @end lisp
  21674. In addition to adding server blocks to the service configuration
  21675. directly, this service can be extended by other services to add server
  21676. blocks, as in this example:
  21677. @lisp
  21678. (simple-service 'my-extra-server nginx-service-type
  21679. (list (nginx-server-configuration
  21680. (root "/srv/http/extra-website")
  21681. (try-files (list "$uri" "$uri/index.html")))))
  21682. @end lisp
  21683. @end deffn
  21684. At startup, @command{nginx} has not yet read its configuration file, so
  21685. it uses a default file to log error messages. If it fails to load its
  21686. configuration file, that is where error messages are logged. After the
  21687. configuration file is loaded, the default error log file changes as per
  21688. configuration. In our case, startup error messages can be found in
  21689. @file{/var/run/nginx/logs/error.log}, and after configuration in
  21690. @file{/var/log/nginx/error.log}. The second location can be changed
  21691. with the @var{log-directory} configuration option.
  21692. @deffn {Data Type} nginx-configuration
  21693. This data type represents the configuration for NGinx. Some
  21694. configuration can be done through this and the other provided record
  21695. types, or alternatively, a config file can be provided.
  21696. @table @asis
  21697. @item @code{nginx} (default: @code{nginx})
  21698. The nginx package to use.
  21699. @item @code{log-directory} (default: @code{"/var/log/nginx"})
  21700. The directory to which NGinx will write log files.
  21701. @item @code{run-directory} (default: @code{"/var/run/nginx"})
  21702. The directory in which NGinx will create a pid file, and write temporary
  21703. files.
  21704. @item @code{server-blocks} (default: @code{'()})
  21705. A list of @dfn{server blocks} to create in the generated configuration
  21706. file, the elements should be of type
  21707. @code{<nginx-server-configuration>}.
  21708. The following example would setup NGinx to serve @code{www.example.com}
  21709. from the @code{/srv/http/www.example.com} directory, without using
  21710. HTTPS.
  21711. @lisp
  21712. (service nginx-service-type
  21713. (nginx-configuration
  21714. (server-blocks
  21715. (list (nginx-server-configuration
  21716. (server-name '("www.example.com"))
  21717. (root "/srv/http/www.example.com"))))))
  21718. @end lisp
  21719. @item @code{upstream-blocks} (default: @code{'()})
  21720. A list of @dfn{upstream blocks} to create in the generated configuration
  21721. file, the elements should be of type
  21722. @code{<nginx-upstream-configuration>}.
  21723. Configuring upstreams through the @code{upstream-blocks} can be useful
  21724. when combined with @code{locations} in the
  21725. @code{<nginx-server-configuration>} records. The following example
  21726. creates a server configuration with one location configuration, that
  21727. will proxy requests to a upstream configuration, which will handle
  21728. requests with two servers.
  21729. @lisp
  21730. (service
  21731. nginx-service-type
  21732. (nginx-configuration
  21733. (server-blocks
  21734. (list (nginx-server-configuration
  21735. (server-name '("www.example.com"))
  21736. (root "/srv/http/www.example.com")
  21737. (locations
  21738. (list
  21739. (nginx-location-configuration
  21740. (uri "/path1")
  21741. (body '("proxy_pass http://server-proxy;"))))))))
  21742. (upstream-blocks
  21743. (list (nginx-upstream-configuration
  21744. (name "server-proxy")
  21745. (servers (list "server1.example.com"
  21746. "server2.example.com")))))))
  21747. @end lisp
  21748. @item @code{file} (default: @code{#f})
  21749. If a configuration @var{file} is provided, this will be used, rather than
  21750. generating a configuration file from the provided @code{log-directory},
  21751. @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
  21752. proper operation, these arguments should match what is in @var{file} to ensure
  21753. that the directories are created when the service is activated.
  21754. This can be useful if you have an existing configuration file, or it's
  21755. not possible to do what is required through the other parts of the
  21756. nginx-configuration record.
  21757. @item @code{server-names-hash-bucket-size} (default: @code{#f})
  21758. Bucket size for the server names hash tables, defaults to @code{#f} to
  21759. use the size of the processors cache line.
  21760. @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
  21761. Maximum bucket size for the server names hash tables.
  21762. @item @code{modules} (default: @code{'()})
  21763. List of nginx dynamic modules to load. This should be a list of file
  21764. names of loadable modules, as in this example:
  21765. @lisp
  21766. (modules
  21767. (list
  21768. (file-append nginx-accept-language-module "\
  21769. /etc/nginx/modules/ngx_http_accept_language_module.so")
  21770. (file-append nginx-lua-module "\
  21771. /etc/nginx/modules/ngx_http_lua_module.so")))
  21772. @end lisp
  21773. @item @code{lua-package-path} (default: @code{'()})
  21774. List of nginx lua packages to load. This should be a list of package
  21775. names of loadable lua modules, as in this example:
  21776. @lisp
  21777. (lua-package-path (list lua-resty-core
  21778. lua-resty-lrucache
  21779. lua-resty-signal
  21780. lua-tablepool
  21781. lua-resty-shell))
  21782. @end lisp
  21783. @item @code{lua-package-cpath} (default: @code{'()})
  21784. List of nginx lua C packages to load. This should be a list of package
  21785. names of loadable lua C modules, as in this example:
  21786. @lisp
  21787. (lua-package-cpath (list lua-resty-signal))
  21788. @end lisp
  21789. @item @code{global-directives} (default: @code{'((events . ()))})
  21790. Association list of global directives for the top level of the nginx
  21791. configuration. Values may themselves be association lists.
  21792. @lisp
  21793. (global-directives
  21794. `((worker_processes . 16)
  21795. (pcre_jit . on)
  21796. (events . ((worker_connections . 1024)))))
  21797. @end lisp
  21798. @item @code{extra-content} (default: @code{""})
  21799. Extra content for the @code{http} block. Should be string or a string
  21800. valued G-expression.
  21801. @end table
  21802. @end deffn
  21803. @anchor{nginx-server-configuration}
  21804. @deftp {Data Type} nginx-server-configuration
  21805. Data type representing the configuration of an nginx server block.
  21806. This type has the following parameters:
  21807. @table @asis
  21808. @item @code{listen} (default: @code{'("80" "443 ssl")})
  21809. Each @code{listen} directive sets the address and port for IP, or the
  21810. path for a UNIX-domain socket on which the server will accept requests.
  21811. Both address and port, or only address or only port can be specified.
  21812. An address may also be a hostname, for example:
  21813. @lisp
  21814. '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
  21815. @end lisp
  21816. @item @code{server-name} (default: @code{(list 'default)})
  21817. A list of server names this server represents. @code{'default} represents the
  21818. default server for connections matching no other server.
  21819. @item @code{root} (default: @code{"/srv/http"})
  21820. Root of the website nginx will serve.
  21821. @item @code{locations} (default: @code{'()})
  21822. A list of @dfn{nginx-location-configuration} or
  21823. @dfn{nginx-named-location-configuration} records to use within this
  21824. server block.
  21825. @item @code{index} (default: @code{(list "index.html")})
  21826. Index files to look for when clients ask for a directory. If it cannot be found,
  21827. Nginx will send the list of files in the directory.
  21828. @item @code{try-files} (default: @code{'()})
  21829. A list of files whose existence is checked in the specified order.
  21830. @code{nginx} will use the first file it finds to process the request.
  21831. @item @code{ssl-certificate} (default: @code{#f})
  21832. Where to find the certificate for secure connections. Set it to @code{#f} if
  21833. you don't have a certificate or you don't want to use HTTPS.
  21834. @item @code{ssl-certificate-key} (default: @code{#f})
  21835. Where to find the private key for secure connections. Set it to @code{#f} if
  21836. you don't have a key or you don't want to use HTTPS.
  21837. @item @code{server-tokens?} (default: @code{#f})
  21838. Whether the server should add its configuration to response.
  21839. @item @code{raw-content} (default: @code{'()})
  21840. A list of raw lines added to the server block.
  21841. @end table
  21842. @end deftp
  21843. @deftp {Data Type} nginx-upstream-configuration
  21844. Data type representing the configuration of an nginx @code{upstream}
  21845. block. This type has the following parameters:
  21846. @table @asis
  21847. @item @code{name}
  21848. Name for this group of servers.
  21849. @item @code{servers}
  21850. Specify the addresses of the servers in the group. The address can be
  21851. specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
  21852. (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
  21853. prefix @samp{unix:}. For addresses using an IP address or domain name,
  21854. the default port is 80, and a different port can be specified
  21855. explicitly.
  21856. @end table
  21857. @end deftp
  21858. @deftp {Data Type} nginx-location-configuration
  21859. Data type representing the configuration of an nginx @code{location}
  21860. block. This type has the following parameters:
  21861. @table @asis
  21862. @item @code{uri}
  21863. URI which this location block matches.
  21864. @anchor{nginx-location-configuration body}
  21865. @item @code{body}
  21866. Body of the location block, specified as a list of strings. This can contain
  21867. many
  21868. configuration directives. For example, to pass requests to a upstream
  21869. server group defined using an @code{nginx-upstream-configuration} block,
  21870. the following directive would be specified in the body @samp{(list "proxy_pass
  21871. http://upstream-name;")}.
  21872. @end table
  21873. @end deftp
  21874. @deftp {Data Type} nginx-named-location-configuration
  21875. Data type representing the configuration of an nginx named location
  21876. block. Named location blocks are used for request redirection, and not
  21877. used for regular request processing. This type has the following
  21878. parameters:
  21879. @table @asis
  21880. @item @code{name}
  21881. Name to identify this location block.
  21882. @item @code{body}
  21883. @xref{nginx-location-configuration body}, as the body for named location
  21884. blocks can be used in a similar way to the
  21885. @code{nginx-location-configuration body}. One restriction is that the
  21886. body of a named location block cannot contain location blocks.
  21887. @end table
  21888. @end deftp
  21889. @subsubheading Varnish Cache
  21890. @cindex Varnish
  21891. Varnish is a fast cache server that sits in between web applications
  21892. and end users. It proxies requests from clients and caches the
  21893. accessed URLs such that multiple requests for the same resource only
  21894. creates one request to the back-end.
  21895. @defvr {Scheme Variable} varnish-service-type
  21896. Service type for the Varnish daemon.
  21897. @end defvr
  21898. @deftp {Data Type} varnish-configuration
  21899. Data type representing the @code{varnish} service configuration.
  21900. This type has the following parameters:
  21901. @table @asis
  21902. @item @code{package} (default: @code{varnish})
  21903. The Varnish package to use.
  21904. @item @code{name} (default: @code{"default"})
  21905. A name for this Varnish instance. Varnish will create a directory in
  21906. @file{/var/varnish/} with this name and keep temporary files there. If
  21907. the name starts with a forward slash, it is interpreted as an absolute
  21908. directory name.
  21909. Pass the @code{-n} argument to other Varnish programs to connect to the
  21910. named instance, e.g.@: @command{varnishncsa -n default}.
  21911. @item @code{backend} (default: @code{"localhost:8080"})
  21912. The backend to use. This option has no effect if @code{vcl} is set.
  21913. @item @code{vcl} (default: #f)
  21914. The @dfn{VCL} (Varnish Configuration Language) program to run. If this
  21915. is @code{#f}, Varnish will proxy @code{backend} using the default
  21916. configuration. Otherwise this must be a file-like object with valid
  21917. VCL syntax.
  21918. @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
  21919. For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
  21920. can do something along these lines:
  21921. @lisp
  21922. (define %gnu-mirror
  21923. (plain-file "gnu.vcl"
  21924. "vcl 4.1;
  21925. backend gnu @{ .host = \"www.gnu.org\"; @}"))
  21926. (operating-system
  21927. ;; @dots{}
  21928. (services (cons (service varnish-service-type
  21929. (varnish-configuration
  21930. (listen '(":80"))
  21931. (vcl %gnu-mirror)))
  21932. %base-services)))
  21933. @end lisp
  21934. The configuration of an already running Varnish instance can be inspected
  21935. and changed using the @command{varnishadm} program.
  21936. Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
  21937. @url{https://book.varnish-software.com/4.0/,Varnish Book} for
  21938. comprehensive documentation on Varnish and its configuration language.
  21939. @item @code{listen} (default: @code{'("localhost:80")})
  21940. List of addresses Varnish will listen on.
  21941. @item @code{storage} (default: @code{'("malloc,128m")})
  21942. List of storage backends that will be available in VCL.
  21943. @item @code{parameters} (default: @code{'()})
  21944. List of run-time parameters in the form @code{'(("parameter" . "value"))}.
  21945. @item @code{extra-options} (default: @code{'()})
  21946. Additional arguments to pass to the @command{varnishd} process.
  21947. @end table
  21948. @end deftp
  21949. @subsubheading Patchwork
  21950. @cindex Patchwork
  21951. Patchwork is a patch tracking system. It can collect patches sent to a
  21952. mailing list, and display them in a web interface.
  21953. @defvr {Scheme Variable} patchwork-service-type
  21954. Service type for Patchwork.
  21955. @end defvr
  21956. The following example is an example of a minimal service for Patchwork, for
  21957. the @code{patchwork.example.com} domain.
  21958. @lisp
  21959. (service patchwork-service-type
  21960. (patchwork-configuration
  21961. (domain "patchwork.example.com")
  21962. (settings-module
  21963. (patchwork-settings-module
  21964. (allowed-hosts (list domain))
  21965. (default-from-email "patchwork@@patchwork.example.com")))
  21966. (getmail-retriever-config
  21967. (getmail-retriever-configuration
  21968. (type "SimpleIMAPSSLRetriever")
  21969. (server "imap.example.com")
  21970. (port 993)
  21971. (username "patchwork")
  21972. (password-command
  21973. (list (file-append coreutils "/bin/cat")
  21974. "/etc/getmail-patchwork-imap-password"))
  21975. (extra-parameters
  21976. '((mailboxes . ("Patches"))))))))
  21977. @end lisp
  21978. There are three records for configuring the Patchwork service. The
  21979. @code{<patchwork-configuration>} relates to the configuration for Patchwork
  21980. within the HTTPD service.
  21981. The @code{settings-module} field within the @code{<patchwork-configuration>}
  21982. record can be populated with the @code{<patchwork-settings-module>} record,
  21983. which describes a settings module that is generated within the Guix store.
  21984. For the @code{database-configuration} field within the
  21985. @code{<patchwork-settings-module>}, the
  21986. @code{<patchwork-database-configuration>} must be used.
  21987. @deftp {Data Type} patchwork-configuration
  21988. Data type representing the Patchwork service configuration. This type has the
  21989. following parameters:
  21990. @table @asis
  21991. @item @code{patchwork} (default: @code{patchwork})
  21992. The Patchwork package to use.
  21993. @item @code{domain}
  21994. The domain to use for Patchwork, this is used in the HTTPD service virtual
  21995. host.
  21996. @item @code{settings-module}
  21997. The settings module to use for Patchwork. As a Django application, Patchwork
  21998. is configured with a Python module containing the settings. This can either be
  21999. an instance of the @code{<patchwork-settings-module>} record, any other record
  22000. that represents the settings in the store, or a directory outside of the
  22001. store.
  22002. @item @code{static-path} (default: @code{"/static/"})
  22003. The path under which the HTTPD service should serve the static files.
  22004. @item @code{getmail-retriever-config}
  22005. The getmail-retriever-configuration record value to use with
  22006. Patchwork. Getmail will be configured with this value, the messages will be
  22007. delivered to Patchwork.
  22008. @end table
  22009. @end deftp
  22010. @deftp {Data Type} patchwork-settings-module
  22011. Data type representing a settings module for Patchwork. Some of these
  22012. settings relate directly to Patchwork, but others relate to Django, the web
  22013. framework used by Patchwork, or the Django Rest Framework library. This type
  22014. has the following parameters:
  22015. @table @asis
  22016. @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
  22017. The database connection settings used for Patchwork. See the
  22018. @code{<patchwork-database-configuration>} record type for more information.
  22019. @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
  22020. Patchwork, as a Django web application uses a secret key for cryptographically
  22021. signing values. This file should contain a unique unpredictable value.
  22022. If this file does not exist, it will be created and populated with a random
  22023. value by the patchwork-setup shepherd service.
  22024. This setting relates to Django.
  22025. @item @code{allowed-hosts}
  22026. A list of valid hosts for this Patchwork service. This should at least include
  22027. the domain specified in the @code{<patchwork-configuration>} record.
  22028. This is a Django setting.
  22029. @item @code{default-from-email}
  22030. The email address from which Patchwork should send email by default.
  22031. This is a Patchwork setting.
  22032. @item @code{static-url} (default: @code{#f})
  22033. The URL to use when serving static assets. It can be part of a URL, or a full
  22034. URL, but must end in a @code{/}.
  22035. If the default value is used, the @code{static-path} value from the
  22036. @code{<patchwork-configuration>} record will be used.
  22037. This is a Django setting.
  22038. @item @code{admins} (default: @code{'()})
  22039. Email addresses to send the details of errors that occur. Each value should
  22040. be a list containing two elements, the name and then the email address.
  22041. This is a Django setting.
  22042. @item @code{debug?} (default: @code{#f})
  22043. Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
  22044. messages will be shown.
  22045. This is a Django setting.
  22046. @item @code{enable-rest-api?} (default: @code{#t})
  22047. Whether to enable the Patchwork REST API.
  22048. This is a Patchwork setting.
  22049. @item @code{enable-xmlrpc?} (default: @code{#t})
  22050. Whether to enable the XML RPC API.
  22051. This is a Patchwork setting.
  22052. @item @code{force-https-links?} (default: @code{#t})
  22053. Whether to use HTTPS links on Patchwork pages.
  22054. This is a Patchwork setting.
  22055. @item @code{extra-settings} (default: @code{""})
  22056. Extra code to place at the end of the Patchwork settings module.
  22057. @end table
  22058. @end deftp
  22059. @deftp {Data Type} patchwork-database-configuration
  22060. Data type representing the database configuration for Patchwork.
  22061. @table @asis
  22062. @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
  22063. The database engine to use.
  22064. @item @code{name} (default: @code{"patchwork"})
  22065. The name of the database to use.
  22066. @item @code{user} (default: @code{"httpd"})
  22067. The user to connect to the database as.
  22068. @item @code{password} (default: @code{""})
  22069. The password to use when connecting to the database.
  22070. @item @code{host} (default: @code{""})
  22071. The host to make the database connection to.
  22072. @item @code{port} (default: @code{""})
  22073. The port on which to connect to the database.
  22074. @end table
  22075. @end deftp
  22076. @subsubheading Mumi
  22077. @cindex Mumi, Debbugs Web interface
  22078. @cindex Debbugs, Mumi Web interface
  22079. @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
  22080. Web interface to the Debbugs bug tracker, by default for
  22081. @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
  22082. but it also fetches and indexes mail retrieved from Debbugs.
  22083. @defvr {Scheme Variable} mumi-service-type
  22084. This is the service type for Mumi.
  22085. @end defvr
  22086. @deftp {Data Type} mumi-configuration
  22087. Data type representing the Mumi service configuration. This type has the
  22088. following fields:
  22089. @table @asis
  22090. @item @code{mumi} (default: @code{mumi})
  22091. The Mumi package to use.
  22092. @item @code{mailer?} (default: @code{#true})
  22093. Whether to enable or disable the mailer component.
  22094. @item @code{mumi-configuration-sender}
  22095. The email address used as the sender for comments.
  22096. @item @code{mumi-configuration-smtp}
  22097. A URI to configure the SMTP settings for Mailutils. This could be
  22098. something like @code{sendmail:///path/to/bin/msmtp} or any other URI
  22099. supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
  22100. mailutils, GNU@tie{}Mailutils}.
  22101. @end table
  22102. @end deftp
  22103. @subsubheading FastCGI
  22104. @cindex fastcgi
  22105. @cindex fcgiwrap
  22106. FastCGI is an interface between the front-end and the back-end of a web
  22107. service. It is a somewhat legacy facility; new web services should
  22108. generally just talk HTTP between the front-end and the back-end.
  22109. However there are a number of back-end services such as PHP or the
  22110. optimized HTTP Git repository access that use FastCGI, so we have
  22111. support for it in Guix.
  22112. To use FastCGI, you configure the front-end web server (e.g., nginx) to
  22113. dispatch some subset of its requests to the fastcgi backend, which
  22114. listens on a local TCP or UNIX socket. There is an intermediary
  22115. @code{fcgiwrap} program that sits between the actual backend process and
  22116. the web server. The front-end indicates which backend program to run,
  22117. passing that information to the @code{fcgiwrap} process.
  22118. @defvr {Scheme Variable} fcgiwrap-service-type
  22119. A service type for the @code{fcgiwrap} FastCGI proxy.
  22120. @end defvr
  22121. @deftp {Data Type} fcgiwrap-configuration
  22122. Data type representing the configuration of the @code{fcgiwrap} service.
  22123. This type has the following parameters:
  22124. @table @asis
  22125. @item @code{package} (default: @code{fcgiwrap})
  22126. The fcgiwrap package to use.
  22127. @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
  22128. The socket on which the @code{fcgiwrap} process should listen, as a
  22129. string. Valid @var{socket} values include
  22130. @code{unix:@var{/path/to/unix/socket}},
  22131. @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
  22132. @code{tcp6:[@var{ipv6_addr}]:port}.
  22133. @item @code{user} (default: @code{fcgiwrap})
  22134. @itemx @code{group} (default: @code{fcgiwrap})
  22135. The user and group names, as strings, under which to run the
  22136. @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
  22137. the user asks for the specific user or group names @code{fcgiwrap} that
  22138. the corresponding user and/or group is present on the system.
  22139. It is possible to configure a FastCGI-backed web service to pass HTTP
  22140. authentication information from the front-end to the back-end, and to
  22141. allow @code{fcgiwrap} to run the back-end process as a corresponding
  22142. local user. To enable this capability on the back-end, run
  22143. @code{fcgiwrap} as the @code{root} user and group. Note that this
  22144. capability also has to be configured on the front-end as well.
  22145. @end table
  22146. @end deftp
  22147. @anchor{PHP-FPM}
  22148. @subsubheading PHP-FPM
  22149. @cindex php-fpm
  22150. PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
  22151. with some additional features useful for sites of any size.
  22152. These features include:
  22153. @itemize @bullet
  22154. @item Adaptive process spawning
  22155. @item Basic statistics (similar to Apache's mod_status)
  22156. @item Advanced process management with graceful stop/start
  22157. @item Ability to start workers with different uid/gid/chroot/environment
  22158. and different php.ini (replaces safe_mode)
  22159. @item Stdout & stderr logging
  22160. @item Emergency restart in case of accidental opcode cache destruction
  22161. @item Accelerated upload support
  22162. @item Support for a "slowlog"
  22163. @item Enhancements to FastCGI, such as fastcgi_finish_request() -
  22164. a special function to finish request & flush all data while continuing to do
  22165. something time-consuming (video converting, stats processing, etc.)
  22166. @end itemize
  22167. ...@: and much more.
  22168. @defvr {Scheme Variable} php-fpm-service-type
  22169. A Service type for @code{php-fpm}.
  22170. @end defvr
  22171. @deftp {Data Type} php-fpm-configuration
  22172. Data Type for php-fpm service configuration.
  22173. @table @asis
  22174. @item @code{php} (default: @code{php})
  22175. The php package to use.
  22176. @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
  22177. The address on which to accept FastCGI requests. Valid syntaxes are:
  22178. @table @asis
  22179. @item @code{"ip.add.re.ss:port"}
  22180. Listen on a TCP socket to a specific address on a specific port.
  22181. @item @code{"port"}
  22182. Listen on a TCP socket to all addresses on a specific port.
  22183. @item @code{"/path/to/unix/socket"}
  22184. Listen on a unix socket.
  22185. @end table
  22186. @item @code{user} (default: @code{php-fpm})
  22187. User who will own the php worker processes.
  22188. @item @code{group} (default: @code{php-fpm})
  22189. Group of the worker processes.
  22190. @item @code{socket-user} (default: @code{php-fpm})
  22191. User who can speak to the php-fpm socket.
  22192. @item @code{socket-group} (default: @code{nginx})
  22193. Group that can speak to the php-fpm socket.
  22194. @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
  22195. The process id of the php-fpm process is written to this file
  22196. once the service has started.
  22197. @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
  22198. Log for the php-fpm master process.
  22199. @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
  22200. Detailed settings for the php-fpm process manager.
  22201. Must be one of:
  22202. @table @asis
  22203. @item @code{<php-fpm-dynamic-process-manager-configuration>}
  22204. @item @code{<php-fpm-static-process-manager-configuration>}
  22205. @item @code{<php-fpm-on-demand-process-manager-configuration>}
  22206. @end table
  22207. @item @code{display-errors} (default @code{#f})
  22208. Determines whether php errors and warning should be sent to clients
  22209. and displayed in their browsers.
  22210. This is useful for local php development, but a security risk for public sites,
  22211. as error messages can reveal passwords and personal data.
  22212. @item @code{timezone} (default @code{#f})
  22213. Specifies @code{php_admin_value[date.timezone]} parameter.
  22214. @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
  22215. This file will log the @code{stderr} outputs of php worker processes.
  22216. Can be set to @code{#f} to disable logging.
  22217. @item @code{file} (default @code{#f})
  22218. An optional override of the whole configuration.
  22219. You can use the @code{mixed-text-file} function or an absolute filepath for it.
  22220. @item @code{php-ini-file} (default @code{#f})
  22221. An optional override of the default php settings.
  22222. It may be any ``file-like'' object (@pxref{G-Expressions, file-like objects}).
  22223. You can use the @code{mixed-text-file} function or an absolute filepath for it.
  22224. For local development it is useful to set a higher timeout and memory
  22225. limit for spawned php processes. This be accomplished with the
  22226. following operating system configuration snippet:
  22227. @lisp
  22228. (define %local-php-ini
  22229. (plain-file "php.ini"
  22230. "memory_limit = 2G
  22231. max_execution_time = 1800"))
  22232. (operating-system
  22233. ;; @dots{}
  22234. (services (cons (service php-fpm-service-type
  22235. (php-fpm-configuration
  22236. (php-ini-file %local-php-ini)))
  22237. %base-services)))
  22238. @end lisp
  22239. Consult the @url{https://www.php.net/manual/en/ini.core.php,core php.ini
  22240. directives} for comprehensive documentation on the acceptable
  22241. @file{php.ini} directives.
  22242. @end table
  22243. @end deftp
  22244. @deftp {Data type} php-fpm-dynamic-process-manager-configuration
  22245. Data Type for the @code{dynamic} php-fpm process manager. With the
  22246. @code{dynamic} process manager, spare worker processes are kept around
  22247. based on its configured limits.
  22248. @table @asis
  22249. @item @code{max-children} (default: @code{5})
  22250. Maximum of worker processes.
  22251. @item @code{start-servers} (default: @code{2})
  22252. How many worker processes should be started on start-up.
  22253. @item @code{min-spare-servers} (default: @code{1})
  22254. How many spare worker processes should be kept around at minimum.
  22255. @item @code{max-spare-servers} (default: @code{3})
  22256. How many spare worker processes should be kept around at maximum.
  22257. @end table
  22258. @end deftp
  22259. @deftp {Data type} php-fpm-static-process-manager-configuration
  22260. Data Type for the @code{static} php-fpm process manager. With the
  22261. @code{static} process manager, an unchanging number of worker processes
  22262. are created.
  22263. @table @asis
  22264. @item @code{max-children} (default: @code{5})
  22265. Maximum of worker processes.
  22266. @end table
  22267. @end deftp
  22268. @deftp {Data type} php-fpm-on-demand-process-manager-configuration
  22269. Data Type for the @code{on-demand} php-fpm process manager. With the
  22270. @code{on-demand} process manager, worker processes are only created as
  22271. requests arrive.
  22272. @table @asis
  22273. @item @code{max-children} (default: @code{5})
  22274. Maximum of worker processes.
  22275. @item @code{process-idle-timeout} (default: @code{10})
  22276. The time in seconds after which a process with no requests is killed.
  22277. @end table
  22278. @end deftp
  22279. @deffn {Scheme Procedure} nginx-php-location @
  22280. [#:nginx-package nginx] @
  22281. [socket (string-append "/var/run/php" @
  22282. (version-major (package-version php)) @
  22283. "-fpm.sock")]
  22284. A helper function to quickly add php to an @code{nginx-server-configuration}.
  22285. @end deffn
  22286. A simple services setup for nginx with php can look like this:
  22287. @lisp
  22288. (services (cons* (service dhcp-client-service-type)
  22289. (service php-fpm-service-type)
  22290. (service nginx-service-type
  22291. (nginx-server-configuration
  22292. (server-name '("example.com"))
  22293. (root "/srv/http/")
  22294. (locations
  22295. (list (nginx-php-location)))
  22296. (listen '("80"))
  22297. (ssl-certificate #f)
  22298. (ssl-certificate-key #f)))
  22299. %base-services))
  22300. @end lisp
  22301. @cindex cat-avatar-generator
  22302. The cat avatar generator is a simple service to demonstrate the use of php-fpm
  22303. in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
  22304. the hash of a user's email address.
  22305. @deffn {Scheme Procedure} cat-avatar-generator-service @
  22306. [#:cache-dir "/var/cache/cat-avatar-generator"] @
  22307. [#:package cat-avatar-generator] @
  22308. [#:configuration (nginx-server-configuration)]
  22309. Returns an nginx-server-configuration that inherits @code{configuration}. It
  22310. extends the nginx configuration to add a server block that serves @code{package},
  22311. a version of cat-avatar-generator. During execution, cat-avatar-generator will
  22312. be able to use @code{cache-dir} as its cache directory.
  22313. @end deffn
  22314. A simple setup for cat-avatar-generator can look like this:
  22315. @lisp
  22316. (services (cons* (cat-avatar-generator-service
  22317. #:configuration
  22318. (nginx-server-configuration
  22319. (server-name '("example.com"))))
  22320. ...
  22321. %base-services))
  22322. @end lisp
  22323. @subsubheading Hpcguix-web
  22324. @cindex hpcguix-web
  22325. The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
  22326. program is a customizable web interface to browse Guix packages,
  22327. initially designed for users of high-performance computing (HPC)
  22328. clusters.
  22329. @defvr {Scheme Variable} hpcguix-web-service-type
  22330. The service type for @code{hpcguix-web}.
  22331. @end defvr
  22332. @deftp {Data Type} hpcguix-web-configuration
  22333. Data type for the hpcguix-web service configuration.
  22334. @table @asis
  22335. @item @code{specs}
  22336. A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
  22337. configuration. The main items available in this spec are:
  22338. @table @asis
  22339. @item @code{title-prefix} (default: @code{"hpcguix | "})
  22340. The page title prefix.
  22341. @item @code{guix-command} (default: @code{"guix"})
  22342. The @command{guix} command.
  22343. @item @code{package-filter-proc} (default: @code{(const #t)})
  22344. A procedure specifying how to filter packages that are displayed.
  22345. @item @code{package-page-extension-proc} (default: @code{(const '())})
  22346. Extension package for @code{hpcguix-web}.
  22347. @item @code{menu} (default: @code{'()})
  22348. Additional entry in page @code{menu}.
  22349. @item @code{channels} (default: @code{%default-channels})
  22350. List of channels from which the package list is built (@pxref{Channels}).
  22351. @item @code{package-list-expiration} (default: @code{(* 12 3600)})
  22352. The expiration time, in seconds, after which the package list is rebuilt from
  22353. the latest instances of the given channels.
  22354. @end table
  22355. See the hpcguix-web repository for a
  22356. @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
  22357. complete example}.
  22358. @item @code{package} (default: @code{hpcguix-web})
  22359. The hpcguix-web package to use.
  22360. @item @code{address} (default: @code{"127.0.0.1"})
  22361. The IP address to listen to.
  22362. @item @code{port} (default: @code{5000})
  22363. The port number to listen to.
  22364. @end table
  22365. @end deftp
  22366. A typical hpcguix-web service declaration looks like this:
  22367. @lisp
  22368. (service hpcguix-web-service-type
  22369. (hpcguix-web-configuration
  22370. (specs
  22371. #~(define site-config
  22372. (hpcweb-configuration
  22373. (title-prefix "Guix-HPC - ")
  22374. (menu '(("/about" "ABOUT"))))))))
  22375. @end lisp
  22376. @quotation Note
  22377. The hpcguix-web service periodically updates the package list it publishes by
  22378. pulling channels from Git. To that end, it needs to access X.509 certificates
  22379. so that it can authenticate Git servers when communicating over HTTPS, and it
  22380. assumes that @file{/etc/ssl/certs} contains those certificates.
  22381. Thus, make sure to add @code{nss-certs} or another certificate package to the
  22382. @code{packages} field of your configuration. @ref{X.509 Certificates}, for
  22383. more information on X.509 certificates.
  22384. @end quotation
  22385. @subsubheading gmnisrv
  22386. @cindex gmnisrv
  22387. The @uref{https://git.sr.ht/~sircmpwn/gmnisrv, gmnisrv} program is a
  22388. simple @uref{https://gemini.circumlunar.space/, Gemini} protocol server.
  22389. @deffn {Scheme Variable} gmnisrv-service-type
  22390. This is the type of the gmnisrv service, whose value should be a
  22391. @code{gmnisrv-configuration} object, as in this example:
  22392. @lisp
  22393. (service gmnisrv-service-type
  22394. (gmnisrv-configuration
  22395. (config-file (local-file "./my-gmnisrv.ini"))))
  22396. @end lisp
  22397. @end deffn
  22398. @deftp {Data Type} gmnisrv-configuration
  22399. Data type representing the configuration of gmnisrv.
  22400. @table @asis
  22401. @item @code{package} (default: @var{gmnisrv})
  22402. Package object of the gmnisrv server.
  22403. @item @code{config-file} (default: @code{%default-gmnisrv-config-file})
  22404. File-like object of the gmnisrv configuration file to use. The default
  22405. configuration listens on port 1965 and serves files from
  22406. @file{/srv/gemini}. Certificates are stored in
  22407. @file{/var/lib/gemini/certs}. For more information, run @command{man
  22408. gmnisrv} and @command{man gmnisrv.ini}.
  22409. @end table
  22410. @end deftp
  22411. @subsubheading Agate
  22412. @cindex agate
  22413. The @uref{gemini://qwertqwefsday.eu/agate.gmi, Agate}
  22414. (@uref{https://github.com/mbrubeck/agate, GitHub page over HTTPS})
  22415. program is a simple @uref{https://gemini.circumlunar.space/, Gemini}
  22416. protocol server written in Rust.
  22417. @deffn {Scheme Variable} agate-service-type
  22418. This is the type of the agate service, whose value should be an
  22419. @code{agate-service-type} object, as in this example:
  22420. @lisp
  22421. (service agate-service-type
  22422. (agate-configuration
  22423. (content "/srv/gemini")
  22424. (cert "/srv/cert.pem")
  22425. (key "/srv/key.rsa")))
  22426. @end lisp
  22427. The example above represents the minimal tweaking necessary to get Agate
  22428. up and running. Specifying the path to the certificate and key is
  22429. always necessary, as the Gemini protocol requires TLS by default.
  22430. To obtain a certificate and a key, you could, for example, use OpenSSL,
  22431. running a command similar to the following example:
  22432. @example
  22433. openssl req -x509 -newkey rsa:4096 -keyout key.rsa -out cert.pem \
  22434. -days 3650 -nodes -subj "/CN=example.com"
  22435. @end example
  22436. Of course, you'll have to replace @i{example.com} with your own domain
  22437. name, and then point the Agate configuration towards the path of the
  22438. generated key and certificate.
  22439. @end deffn
  22440. @deftp {Data Type} agate-configuration
  22441. Data type representing the configuration of Agate.
  22442. @table @asis
  22443. @item @code{package} (default: @code{agate})
  22444. The package object of the Agate server.
  22445. @item @code{content} (default: @file{"/srv/gemini"})
  22446. The directory from which Agate will serve files.
  22447. @item @code{cert} (default: @code{#f})
  22448. The path to the TLS certificate PEM file to be used for encrypted
  22449. connections. Must be filled in with a value from the user.
  22450. @item @code{key} (default: @code{#f})
  22451. The path to the PKCS8 private key file to be used for encrypted
  22452. connections. Must be filled in with a value from the user.
  22453. @item @code{addr} (default: @code{'("0.0.0.0:1965" "[::]:1965")})
  22454. A list of the addresses to listen on.
  22455. @item @code{hostname} (default: @code{#f})
  22456. The domain name of this Gemini server. Optional.
  22457. @item @code{lang} (default: @code{#f})
  22458. RFC 4646 language code(s) for text/gemini documents. Optional.
  22459. @item @code{silent?} (default: @code{#f})
  22460. Set to @code{#t} to disable logging output.
  22461. @item @code{serve-secret?} (default: @code{#f})
  22462. Set to @code{#t} to serve secret files (files/directories starting with
  22463. a dot).
  22464. @item @code{log-ip?} (default: @code{#t})
  22465. Whether or not to output IP addresses when logging.
  22466. @item @code{user} (default: @code{"agate"})
  22467. Owner of the @code{agate} process.
  22468. @item @code{group} (default: @code{"agate"})
  22469. Owner's group of the @code{agate} process.
  22470. @item @code{log-file} (default: @file{"/var/log/agate.log"})
  22471. The file which should store the logging output of Agate.
  22472. @end table
  22473. @end deftp
  22474. @node Certificate Services
  22475. @subsection Certificate Services
  22476. @cindex Web
  22477. @cindex HTTP, HTTPS
  22478. @cindex Let's Encrypt
  22479. @cindex TLS certificates
  22480. The @code{(gnu services certbot)} module provides a service to
  22481. automatically obtain a valid TLS certificate from the Let's Encrypt
  22482. certificate authority. These certificates can then be used to serve
  22483. content securely over HTTPS or other TLS-based protocols, with the
  22484. knowledge that the client will be able to verify the server's
  22485. authenticity.
  22486. @url{https://letsencrypt.org/, Let's Encrypt} provides the
  22487. @code{certbot} tool to automate the certification process. This tool
  22488. first securely generates a key on the server. It then makes a request
  22489. to the Let's Encrypt certificate authority (CA) to sign the key. The CA
  22490. checks that the request originates from the host in question by using a
  22491. challenge-response protocol, requiring the server to provide its
  22492. response over HTTP@. If that protocol completes successfully, the CA
  22493. signs the key, resulting in a certificate. That certificate is valid
  22494. for a limited period of time, and therefore to continue to provide TLS
  22495. services, the server needs to periodically ask the CA to renew its
  22496. signature.
  22497. The certbot service automates this process: the initial key
  22498. generation, the initial certification request to the Let's Encrypt
  22499. service, the web server challenge/response integration, writing the
  22500. certificate to disk, the automated periodic renewals, and the deployment
  22501. tasks associated with the renewal (e.g.@: reloading services, copying keys
  22502. with different permissions).
  22503. Certbot is run twice a day, at a random minute within the hour. It
  22504. won't do anything until your certificates are due for renewal or
  22505. revoked, but running it regularly would give your service a chance of
  22506. staying online in case a Let's Encrypt-initiated revocation happened for
  22507. some reason.
  22508. By using this service, you agree to the ACME Subscriber Agreement, which
  22509. can be found there:
  22510. @url{https://acme-v01.api.letsencrypt.org/directory}.
  22511. @defvr {Scheme Variable} certbot-service-type
  22512. A service type for the @code{certbot} Let's Encrypt client. Its value
  22513. must be a @code{certbot-configuration} record as in this example:
  22514. @lisp
  22515. (define %nginx-deploy-hook
  22516. (program-file
  22517. "nginx-deploy-hook"
  22518. #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
  22519. (kill pid SIGHUP))))
  22520. (service certbot-service-type
  22521. (certbot-configuration
  22522. (email "foo@@example.net")
  22523. (certificates
  22524. (list
  22525. (certificate-configuration
  22526. (domains '("example.net" "www.example.net"))
  22527. (deploy-hook %nginx-deploy-hook))
  22528. (certificate-configuration
  22529. (domains '("bar.example.net")))))))
  22530. @end lisp
  22531. See below for details about @code{certbot-configuration}.
  22532. @end defvr
  22533. @deftp {Data Type} certbot-configuration
  22534. Data type representing the configuration of the @code{certbot} service.
  22535. This type has the following parameters:
  22536. @table @asis
  22537. @item @code{package} (default: @code{certbot})
  22538. The certbot package to use.
  22539. @item @code{webroot} (default: @code{/var/www})
  22540. The directory from which to serve the Let's Encrypt challenge/response
  22541. files.
  22542. @item @code{certificates} (default: @code{()})
  22543. A list of @code{certificates-configuration}s for which to generate
  22544. certificates and request signatures. Each certificate has a @code{name}
  22545. and several @code{domains}.
  22546. @item @code{email} (default: @code{#f})
  22547. Optional email address used for registration and recovery contact.
  22548. Setting this is encouraged as it allows you to receive important
  22549. notifications about the account and issued certificates.
  22550. @item @code{server} (default: @code{#f})
  22551. Optional URL of ACME server. Setting this overrides certbot's default,
  22552. which is the Let's Encrypt server.
  22553. @item @code{rsa-key-size} (default: @code{2048})
  22554. Size of the RSA key.
  22555. @item @code{default-location} (default: @i{see below})
  22556. The default @code{nginx-location-configuration}. Because @code{certbot}
  22557. needs to be able to serve challenges and responses, it needs to be able
  22558. to run a web server. It does so by extending the @code{nginx} web
  22559. service with an @code{nginx-server-configuration} listening on the
  22560. @var{domains} on port 80, and which has a
  22561. @code{nginx-location-configuration} for the @code{/.well-known/} URI
  22562. path subspace used by Let's Encrypt. @xref{Web Services}, for more on
  22563. these nginx configuration data types.
  22564. Requests to other URL paths will be matched by the
  22565. @code{default-location}, which if present is added to all
  22566. @code{nginx-server-configuration}s.
  22567. By default, the @code{default-location} will issue a redirect from
  22568. @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
  22569. you to define what to serve on your site via @code{https}.
  22570. Pass @code{#f} to not issue a default location.
  22571. @end table
  22572. @end deftp
  22573. @deftp {Data Type} certificate-configuration
  22574. Data type representing the configuration of a certificate.
  22575. This type has the following parameters:
  22576. @table @asis
  22577. @item @code{name} (default: @i{see below})
  22578. This name is used by Certbot for housekeeping and in file paths; it
  22579. doesn't affect the content of the certificate itself. To see
  22580. certificate names, run @code{certbot certificates}.
  22581. Its default is the first provided domain.
  22582. @item @code{domains} (default: @code{()})
  22583. The first domain provided will be the subject CN of the certificate, and
  22584. all domains will be Subject Alternative Names on the certificate.
  22585. @item @code{challenge} (default: @code{#f})
  22586. The challenge type that has to be run by certbot. If @code{#f} is specified,
  22587. default to the HTTP challenge. If a value is specified, defaults to the
  22588. manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
  22589. the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
  22590. and gives Let's Encrypt permission to log the public IP address of the
  22591. requesting machine.
  22592. @item @code{csr} (default: @code{#f})
  22593. File name of Certificate Signing Request (CSR) in DER or PEM format.
  22594. If @code{#f} is specified, this argument will not be passed to certbot.
  22595. If a value is specified, certbot will use it to obtain a certificate, instead of
  22596. using a self-generated CSR.
  22597. The domain-name(s) mentioned in @code{domains}, must be consistent with the
  22598. domain-name(s) mentioned in CSR file.
  22599. @item @code{authentication-hook} (default: @code{#f})
  22600. Command to be run in a shell once for each certificate challenge to be
  22601. answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
  22602. will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
  22603. contains the validation string and @code{$CERTBOT_TOKEN} contains the
  22604. file name of the resource requested when performing an HTTP-01 challenge.
  22605. @item @code{cleanup-hook} (default: @code{#f})
  22606. Command to be run in a shell once for each certificate challenge that
  22607. have been answered by the @code{auth-hook}. For this command, the shell
  22608. variables available in the @code{auth-hook} script are still available, and
  22609. additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
  22610. of the @code{auth-hook} script.
  22611. @item @code{deploy-hook} (default: @code{#f})
  22612. Command to be run in a shell once for each successfully issued
  22613. certificate. For this command, the shell variable
  22614. @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
  22615. example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
  22616. certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
  22617. contain a space-delimited list of renewed certificate domains (for
  22618. example, @samp{"example.com www.example.com"}.
  22619. @end table
  22620. @end deftp
  22621. For each @code{certificate-configuration}, the certificate is saved to
  22622. @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
  22623. saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
  22624. @node DNS Services
  22625. @subsection DNS Services
  22626. @cindex DNS (domain name system)
  22627. @cindex domain name system (DNS)
  22628. The @code{(gnu services dns)} module provides services related to the
  22629. @dfn{domain name system} (DNS). It provides a server service for hosting
  22630. an @emph{authoritative} DNS server for multiple zones, slave or master.
  22631. This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
  22632. caching and forwarding DNS server for the LAN, which uses
  22633. @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
  22634. @subsubheading Knot Service
  22635. An example configuration of an authoritative server for two zones, one master
  22636. and one slave, is:
  22637. @lisp
  22638. (define-zone-entries example.org.zone
  22639. ;; Name TTL Class Type Data
  22640. ("@@" "" "IN" "A" "127.0.0.1")
  22641. ("@@" "" "IN" "NS" "ns")
  22642. ("ns" "" "IN" "A" "127.0.0.1"))
  22643. (define master-zone
  22644. (knot-zone-configuration
  22645. (domain "example.org")
  22646. (zone (zone-file
  22647. (origin "example.org")
  22648. (entries example.org.zone)))))
  22649. (define slave-zone
  22650. (knot-zone-configuration
  22651. (domain "plop.org")
  22652. (dnssec-policy "default")
  22653. (master (list "plop-master"))))
  22654. (define plop-master
  22655. (knot-remote-configuration
  22656. (id "plop-master")
  22657. (address (list "208.76.58.171"))))
  22658. (operating-system
  22659. ;; ...
  22660. (services (cons* (service knot-service-type
  22661. (knot-configuration
  22662. (remotes (list plop-master))
  22663. (zones (list master-zone slave-zone))))
  22664. ;; ...
  22665. %base-services)))
  22666. @end lisp
  22667. @deffn {Scheme Variable} knot-service-type
  22668. This is the type for the Knot DNS server.
  22669. Knot DNS is an authoritative DNS server, meaning that it can serve multiple
  22670. zones, that is to say domain names you would buy from a registrar. This server
  22671. is not a resolver, meaning that it can only resolve names for which it is
  22672. authoritative. This server can be configured to serve zones as a master server
  22673. or a slave server as a per-zone basis. Slave zones will get their data from
  22674. masters, and will serve it as an authoritative server. From the point of view
  22675. of a resolver, there is no difference between master and slave.
  22676. The following data types are used to configure the Knot DNS server:
  22677. @end deffn
  22678. @deftp {Data Type} knot-key-configuration
  22679. Data type representing a key.
  22680. This type has the following parameters:
  22681. @table @asis
  22682. @item @code{id} (default: @code{""})
  22683. An identifier for other configuration fields to refer to this key. IDs must
  22684. be unique and must not be empty.
  22685. @item @code{algorithm} (default: @code{#f})
  22686. The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
  22687. @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
  22688. and @code{'hmac-sha512}.
  22689. @item @code{secret} (default: @code{""})
  22690. The secret key itself.
  22691. @end table
  22692. @end deftp
  22693. @deftp {Data Type} knot-acl-configuration
  22694. Data type representing an Access Control List (ACL) configuration.
  22695. This type has the following parameters:
  22696. @table @asis
  22697. @item @code{id} (default: @code{""})
  22698. An identifier for other configuration fields to refer to this key. IDs must be
  22699. unique and must not be empty.
  22700. @item @code{address} (default: @code{'()})
  22701. An ordered list of IP addresses, network subnets, or network ranges represented
  22702. with strings. The query must match one of them. Empty value means that
  22703. address match is not required.
  22704. @item @code{key} (default: @code{'()})
  22705. An ordered list of references to keys represented with strings. The string
  22706. must match a key ID defined in a @code{knot-key-configuration}. No key means
  22707. that a key is not require to match that ACL.
  22708. @item @code{action} (default: @code{'()})
  22709. An ordered list of actions that are permitted or forbidden by this ACL@. Possible
  22710. values are lists of zero or more elements from @code{'transfer}, @code{'notify}
  22711. and @code{'update}.
  22712. @item @code{deny?} (default: @code{#f})
  22713. When true, the ACL defines restrictions. Listed actions are forbidden. When
  22714. false, listed actions are allowed.
  22715. @end table
  22716. @end deftp
  22717. @deftp {Data Type} zone-entry
  22718. Data type representing a record entry in a zone file.
  22719. This type has the following parameters:
  22720. @table @asis
  22721. @item @code{name} (default: @code{"@@"})
  22722. The name of the record. @code{"@@"} refers to the origin of the zone. Names
  22723. are relative to the origin of the zone. For example, in the @code{example.org}
  22724. zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
  22725. Names ending with a dot are absolute, which means that @code{"ns.example.org."}
  22726. refers to @code{ns.example.org}.
  22727. @item @code{ttl} (default: @code{""})
  22728. The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
  22729. @item @code{class} (default: @code{"IN"})
  22730. The class of the record. Knot currently supports only @code{"IN"} and
  22731. partially @code{"CH"}.
  22732. @item @code{type} (default: @code{"A"})
  22733. The type of the record. Common types include A (IPv4 address), AAAA (IPv6
  22734. address), NS (Name Server) and MX (Mail eXchange). Many other types are
  22735. defined.
  22736. @item @code{data} (default: @code{""})
  22737. The data contained in the record. For instance an IP address associated with
  22738. an A record, or a domain name associated with an NS record. Remember that
  22739. domain names are relative to the origin unless they end with a dot.
  22740. @end table
  22741. @end deftp
  22742. @deftp {Data Type} zone-file
  22743. Data type representing the content of a zone file.
  22744. This type has the following parameters:
  22745. @table @asis
  22746. @item @code{entries} (default: @code{'()})
  22747. The list of entries. The SOA record is taken care of, so you don't need to
  22748. put it in the list of entries. This list should probably contain an entry
  22749. for your primary authoritative DNS server. Other than using a list of entries
  22750. directly, you can use @code{define-zone-entries} to define a object containing
  22751. the list of entries more easily, that you can later pass to the @code{entries}
  22752. field of the @code{zone-file}.
  22753. @item @code{origin} (default: @code{""})
  22754. The name of your zone. This parameter cannot be empty.
  22755. @item @code{ns} (default: @code{"ns"})
  22756. The domain of your primary authoritative DNS server. The name is relative to
  22757. the origin, unless it ends with a dot. It is mandatory that this primary
  22758. DNS server corresponds to an NS record in the zone and that it is associated
  22759. to an IP address in the list of entries.
  22760. @item @code{mail} (default: @code{"hostmaster"})
  22761. An email address people can contact you at, as the owner of the zone. This
  22762. is translated as @code{<mail>@@<origin>}.
  22763. @item @code{serial} (default: @code{1})
  22764. The serial number of the zone. As this is used to keep track of changes by
  22765. both slaves and resolvers, it is mandatory that it @emph{never} decreases.
  22766. Always increment it when you make a change in your zone.
  22767. @item @code{refresh} (default: @code{(* 2 24 3600)})
  22768. The frequency at which slaves will do a zone transfer. This value is a number
  22769. of seconds. It can be computed by multiplications or with
  22770. @code{(string->duration)}.
  22771. @item @code{retry} (default: @code{(* 15 60)})
  22772. The period after which a slave will retry to contact its master when it fails
  22773. to do so a first time.
  22774. @item @code{expiry} (default: @code{(* 14 24 3600)})
  22775. Default TTL of records. Existing records are considered correct for at most
  22776. this amount of time. After this period, resolvers will invalidate their cache
  22777. and check again that it still exists.
  22778. @item @code{nx} (default: @code{3600})
  22779. Default TTL of inexistent records. This delay is usually short because you want
  22780. your new domains to reach everyone quickly.
  22781. @end table
  22782. @end deftp
  22783. @deftp {Data Type} knot-remote-configuration
  22784. Data type representing a remote configuration.
  22785. This type has the following parameters:
  22786. @table @asis
  22787. @item @code{id} (default: @code{""})
  22788. An identifier for other configuration fields to refer to this remote. IDs must
  22789. be unique and must not be empty.
  22790. @item @code{address} (default: @code{'()})
  22791. An ordered list of destination IP addresses. Addresses are tried in sequence.
  22792. An optional port can be given with the @@ separator. For instance:
  22793. @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
  22794. @item @code{via} (default: @code{'()})
  22795. An ordered list of source IP addresses. An empty list will have Knot choose
  22796. an appropriate source IP@. An optional port can be given with the @@ separator.
  22797. The default is to choose at random.
  22798. @item @code{key} (default: @code{#f})
  22799. A reference to a key, that is a string containing the identifier of a key
  22800. defined in a @code{knot-key-configuration} field.
  22801. @end table
  22802. @end deftp
  22803. @deftp {Data Type} knot-keystore-configuration
  22804. Data type representing a keystore to hold dnssec keys.
  22805. This type has the following parameters:
  22806. @table @asis
  22807. @item @code{id} (default: @code{""})
  22808. The id of the keystore. It must not be empty.
  22809. @item @code{backend} (default: @code{'pem})
  22810. The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
  22811. @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
  22812. The configuration string of the backend. An example for the PKCS#11 is:
  22813. @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
  22814. For the pem backend, the string represents a path in the file system.
  22815. @end table
  22816. @end deftp
  22817. @deftp {Data Type} knot-policy-configuration
  22818. Data type representing a dnssec policy. Knot DNS is able to automatically
  22819. sign your zones. It can either generate and manage your keys automatically or
  22820. use keys that you generate.
  22821. Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
  22822. used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
  22823. zone. In order to be trusted, the KSK needs to be present in the parent zone
  22824. (usually a top-level domain). If your registrar supports dnssec, you will
  22825. have to send them your KSK's hash so they can add a DS record in their zone.
  22826. This is not automated and need to be done each time you change your KSK.
  22827. The policy also defines the lifetime of keys. Usually, ZSK can be changed
  22828. easily and use weaker cryptographic functions (they use lower parameters) in
  22829. order to sign records quickly, so they are changed often. The KSK however
  22830. requires manual interaction with the registrar, so they are changed less often
  22831. and use stronger parameters because they sign only one record.
  22832. This type has the following parameters:
  22833. @table @asis
  22834. @item @code{id} (default: @code{""})
  22835. The id of the policy. It must not be empty.
  22836. @item @code{keystore} (default: @code{"default"})
  22837. A reference to a keystore, that is a string containing the identifier of a
  22838. keystore defined in a @code{knot-keystore-configuration} field. The
  22839. @code{"default"} identifier means the default keystore (a kasp database that
  22840. was setup by this service).
  22841. @item @code{manual?} (default: @code{#f})
  22842. Whether the key management is manual or automatic.
  22843. @item @code{single-type-signing?} (default: @code{#f})
  22844. When @code{#t}, use the Single-Type Signing Scheme.
  22845. @item @code{algorithm} (default: @code{"ecdsap256sha256"})
  22846. An algorithm of signing keys and issued signatures.
  22847. @item @code{ksk-size} (default: @code{256})
  22848. The length of the KSK@. Note that this value is correct for the default
  22849. algorithm, but would be unsecure for other algorithms.
  22850. @item @code{zsk-size} (default: @code{256})
  22851. The length of the ZSK@. Note that this value is correct for the default
  22852. algorithm, but would be unsecure for other algorithms.
  22853. @item @code{dnskey-ttl} (default: @code{'default})
  22854. The TTL value for DNSKEY records added into zone apex. The special
  22855. @code{'default} value means same as the zone SOA TTL.
  22856. @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
  22857. The period between ZSK publication and the next rollover initiation.
  22858. @item @code{propagation-delay} (default: @code{(* 24 3600)})
  22859. An extra delay added for each key rollover step. This value should be high
  22860. enough to cover propagation of data from the master server to all slaves.
  22861. @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
  22862. A validity period of newly issued signatures.
  22863. @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
  22864. A period how long before a signature expiration the signature will be refreshed.
  22865. @item @code{nsec3?} (default: @code{#f})
  22866. When @code{#t}, NSEC3 will be used instead of NSEC.
  22867. @item @code{nsec3-iterations} (default: @code{5})
  22868. The number of additional times the hashing is performed.
  22869. @item @code{nsec3-salt-length} (default: @code{8})
  22870. The length of a salt field in octets, which is appended to the original owner
  22871. name before hashing.
  22872. @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
  22873. The validity period of newly issued salt field.
  22874. @end table
  22875. @end deftp
  22876. @deftp {Data Type} knot-zone-configuration
  22877. Data type representing a zone served by Knot.
  22878. This type has the following parameters:
  22879. @table @asis
  22880. @item @code{domain} (default: @code{""})
  22881. The domain served by this configuration. It must not be empty.
  22882. @item @code{file} (default: @code{""})
  22883. The file where this zone is saved. This parameter is ignored by master zones.
  22884. Empty means default location that depends on the domain name.
  22885. @item @code{zone} (default: @code{(zone-file)})
  22886. The content of the zone file. This parameter is ignored by slave zones. It
  22887. must contain a zone-file record.
  22888. @item @code{master} (default: @code{'()})
  22889. A list of master remotes. When empty, this zone is a master. When set, this
  22890. zone is a slave. This is a list of remotes identifiers.
  22891. @item @code{ddns-master} (default: @code{#f})
  22892. The main master. When empty, it defaults to the first master in the list of
  22893. masters.
  22894. @item @code{notify} (default: @code{'()})
  22895. A list of slave remote identifiers.
  22896. @item @code{acl} (default: @code{'()})
  22897. A list of acl identifiers.
  22898. @item @code{semantic-checks?} (default: @code{#f})
  22899. When set, this adds more semantic checks to the zone.
  22900. @item @code{zonefile-sync} (default: @code{0})
  22901. The delay between a modification in memory and on disk. 0 means immediate
  22902. synchronization.
  22903. @item @code{zonefile-load} (default: @code{#f})
  22904. The way the zone file contents are applied during zone load. Possible values
  22905. are:
  22906. @itemize
  22907. @item @code{#f} for using the default value from Knot,
  22908. @item @code{'none} for not using the zone file at all,
  22909. @item @code{'difference} for computing the difference between already available
  22910. contents and zone contents and applying it to the current zone contents,
  22911. @item @code{'difference-no-serial} for the same as @code{'difference}, but
  22912. ignoring the SOA serial in the zone file, while the server takes care of it
  22913. automatically.
  22914. @item @code{'whole} for loading zone contents from the zone file.
  22915. @end itemize
  22916. @item @code{journal-content} (default: @code{#f})
  22917. The way the journal is used to store zone and its changes. Possible values
  22918. are @code{'none} to not use it at all, @code{'changes} to store changes and
  22919. @code{'all} to store contents. @code{#f} does not set this option, so the
  22920. default value from Knot is used.
  22921. @item @code{max-journal-usage} (default: @code{#f})
  22922. The maximum size for the journal on disk. @code{#f} does not set this option,
  22923. so the default value from Knot is used.
  22924. @item @code{max-journal-depth} (default: @code{#f})
  22925. The maximum size of the history. @code{#f} does not set this option, so the
  22926. default value from Knot is used.
  22927. @item @code{max-zone-size} (default: @code{#f})
  22928. The maximum size of the zone file. This limit is enforced for incoming
  22929. transfer and updates. @code{#f} does not set this option, so the default
  22930. value from Knot is used.
  22931. @item @code{dnssec-policy} (default: @code{#f})
  22932. A reference to a @code{knot-policy-configuration} record, or the special
  22933. name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
  22934. on this zone.
  22935. @item @code{serial-policy} (default: @code{'increment})
  22936. A policy between @code{'increment} and @code{'unixtime}.
  22937. @end table
  22938. @end deftp
  22939. @deftp {Data Type} knot-configuration
  22940. Data type representing the Knot configuration.
  22941. This type has the following parameters:
  22942. @table @asis
  22943. @item @code{knot} (default: @code{knot})
  22944. The Knot package.
  22945. @item @code{run-directory} (default: @code{"/var/run/knot"})
  22946. The run directory. This directory will be used for pid file and sockets.
  22947. @item @code{includes} (default: @code{'()})
  22948. A list of strings or file-like objects denoting other files that must be
  22949. included at the top of the configuration file.
  22950. @cindex secrets, Knot service
  22951. This can be used to manage secrets out-of-band. For example, secret
  22952. keys may be stored in an out-of-band file not managed by Guix, and
  22953. thus not visible in @file{/gnu/store}---e.g., you could store secret
  22954. key configuration in @file{/etc/knot/secrets.conf} and add this file
  22955. to the @code{includes} list.
  22956. One can generate a secret tsig key (for nsupdate and zone transfers with the
  22957. keymgr command from the knot package. Note that the package is not automatically
  22958. installed by the service. The following example shows how to generate a new
  22959. tsig key:
  22960. @example
  22961. keymgr -t mysecret > /etc/knot/secrets.conf
  22962. chmod 600 /etc/knot/secrets.conf
  22963. @end example
  22964. Also note that the generated key will be named @var{mysecret}, so it is the
  22965. name that needs to be used in the @var{key} field of the
  22966. @code{knot-acl-configuration} record and in other places that need to refer
  22967. to that key.
  22968. It can also be used to add configuration not supported by this interface.
  22969. @item @code{listen-v4} (default: @code{"0.0.0.0"})
  22970. An ip address on which to listen.
  22971. @item @code{listen-v6} (default: @code{"::"})
  22972. An ip address on which to listen.
  22973. @item @code{listen-port} (default: @code{53})
  22974. A port on which to listen.
  22975. @item @code{keys} (default: @code{'()})
  22976. The list of knot-key-configuration used by this configuration.
  22977. @item @code{acls} (default: @code{'()})
  22978. The list of knot-acl-configuration used by this configuration.
  22979. @item @code{remotes} (default: @code{'()})
  22980. The list of knot-remote-configuration used by this configuration.
  22981. @item @code{zones} (default: @code{'()})
  22982. The list of knot-zone-configuration used by this configuration.
  22983. @end table
  22984. @end deftp
  22985. @subsubheading Knot Resolver Service
  22986. @deffn {Scheme Variable} knot-resolver-service-type
  22987. This is the type of the knot resolver service, whose value should be
  22988. an @code{knot-resolver-configuration} object as in this example:
  22989. @lisp
  22990. (service knot-resolver-service-type
  22991. (knot-resolver-configuration
  22992. (kresd-config-file (plain-file "kresd.conf" "
  22993. net.listen('192.168.0.1', 5353)
  22994. user('knot-resolver', 'knot-resolver')
  22995. modules = @{ 'hints > iterate', 'stats', 'predict' @}
  22996. cache.size = 100 * MB
  22997. "))))
  22998. @end lisp
  22999. For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
  23000. @end deffn
  23001. @deftp {Data Type} knot-resolver-configuration
  23002. Data type representing the configuration of knot-resolver.
  23003. @table @asis
  23004. @item @code{package} (default: @var{knot-resolver})
  23005. Package object of the knot DNS resolver.
  23006. @item @code{kresd-config-file} (default: %kresd.conf)
  23007. File-like object of the kresd configuration file to use, by default it
  23008. will listen on @code{127.0.0.1} and @code{::1}.
  23009. @item @code{garbage-collection-interval} (default: 1000)
  23010. Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
  23011. @end table
  23012. @end deftp
  23013. @subsubheading Dnsmasq Service
  23014. @deffn {Scheme Variable} dnsmasq-service-type
  23015. This is the type of the dnsmasq service, whose value should be an
  23016. @code{dnsmasq-configuration} object as in this example:
  23017. @lisp
  23018. (service dnsmasq-service-type
  23019. (dnsmasq-configuration
  23020. (no-resolv? #t)
  23021. (servers '("192.168.1.1"))))
  23022. @end lisp
  23023. @end deffn
  23024. @deftp {Data Type} dnsmasq-configuration
  23025. Data type representing the configuration of dnsmasq.
  23026. @table @asis
  23027. @item @code{package} (default: @var{dnsmasq})
  23028. Package object of the dnsmasq server.
  23029. @item @code{no-hosts?} (default: @code{#f})
  23030. When true, don't read the hostnames in /etc/hosts.
  23031. @item @code{port} (default: @code{53})
  23032. The port to listen on. Setting this to zero completely disables DNS
  23033. responses, leaving only DHCP and/or TFTP functions.
  23034. @item @code{local-service?} (default: @code{#t})
  23035. Accept DNS queries only from hosts whose address is on a local subnet,
  23036. ie a subnet for which an interface exists on the server.
  23037. @item @code{listen-addresses} (default: @code{'()})
  23038. Listen on the given IP addresses.
  23039. @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
  23040. The file to read the IP address of the upstream nameservers from.
  23041. @item @code{no-resolv?} (default: @code{#f})
  23042. When true, don't read @var{resolv-file}.
  23043. @item @code{forward-private-reverse-lookup?} (default: @code{#t})
  23044. When false, all reverse lookups for private IP ranges are answered with
  23045. "no such domain" rather than being forwarded upstream.
  23046. @item @code{query-servers-in-order?} (default: @code{#f})
  23047. When true, dnsmasq queries the servers in the same order as they appear
  23048. in @var{servers}.
  23049. @item @code{servers} (default: @code{'()})
  23050. Specify IP address of upstream servers directly.
  23051. @item @code{addresses} (default: @code{'()})
  23052. For each entry, specify an IP address to return for any host in the
  23053. given domains. Queries in the domains are never forwarded and always
  23054. replied to with the specified IP address.
  23055. This is useful for redirecting hosts locally, for example:
  23056. @lisp
  23057. (service dnsmasq-service-type
  23058. (dnsmasq-configuration
  23059. (addresses
  23060. '(; Redirect to a local web-server.
  23061. "/example.org/127.0.0.1"
  23062. ; Redirect subdomain to a specific IP.
  23063. "/subdomain.example.org/192.168.1.42"))))
  23064. @end lisp
  23065. Note that rules in @file{/etc/hosts} take precedence over this.
  23066. @item @code{cache-size} (default: @code{150})
  23067. Set the size of dnsmasq's cache. Setting the cache size to zero
  23068. disables caching.
  23069. @item @code{negative-cache?} (default: @code{#t})
  23070. When false, disable negative caching.
  23071. @item @code{cpe-id} (default: @code{#f})
  23072. If set, add a CPE (Customer-Premises Equipment) identifier to DNS
  23073. queries which are forwarded upstream.
  23074. @item @code{tftp-enable?} (default: @code{#f})
  23075. Whether to enable the built-in TFTP server.
  23076. @item @code{tftp-no-fail?} (default: @code{#f})
  23077. If true, does not fail dnsmasq if the TFTP server could not start up.
  23078. @item @code{tftp-single-port?} (default: @code{#f})
  23079. Whether to use only one single port for TFTP.
  23080. @item @code{tftp-secure?} (default: @code{#f})
  23081. If true, only files owned by the user running the dnsmasq process are accessible.
  23082. If dnsmasq is being run as root, different rules apply:
  23083. @code{tftp-secure?} has no effect, but only files which have the
  23084. world-readable bit set are accessible.
  23085. @item @code{tftp-max} (default: @code{#f})
  23086. If set, sets the maximal number of concurrent connections allowed.
  23087. @item @code{tftp-mtu} (default: @code{#f})
  23088. If set, sets the MTU for TFTP packets to that value.
  23089. @item @code{tftp-no-blocksize?} (default: @code{#f})
  23090. If true, stops the TFTP server from negotiating the blocksize with a client.
  23091. @item @code{tftp-lowercase?} (default: @code{#f})
  23092. Whether to convert all filenames in TFTP requests to lowercase.
  23093. @item @code{tftp-port-range} (default: @code{#f})
  23094. If set, fixes the dynamical ports (one per client) to the given range
  23095. (@code{"<start>,<end>"}).
  23096. @item @code{tftp-root} (default: @code{/var/empty,lo})
  23097. Look for files to transfer using TFTP relative to the given directory.
  23098. When this is set, TFTP paths which include @samp{..} are rejected, to stop clients
  23099. getting outside the specified root. Absolute paths (starting with @samp{/}) are
  23100. allowed, but they must be within the TFTP-root. If the optional interface
  23101. argument is given, the directory is only used for TFTP requests via that
  23102. interface.
  23103. @item @code{tftp-unique-root} (default: @code{#f})
  23104. If set, add the IP or hardware address of the TFTP client as a path component
  23105. on the end of the TFTP-root. Only valid if a TFTP root is set and the
  23106. directory exists. Defaults to adding IP address (in standard dotted-quad
  23107. format).
  23108. For instance, if @option{--tftp-root} is @samp{/tftp} and client
  23109. @samp{1.2.3.4} requests file @file{myfile} then the effective path will
  23110. be @file{/tftp/1.2.3.4/myfile} if @file{/tftp/1.2.3.4} exists or
  23111. @file{/tftp/myfile} otherwise. When @samp{=mac} is specified it will
  23112. append the MAC address instead, using lowercase zero padded digits
  23113. separated by dashes, e.g.: @samp{01-02-03-04-aa-bb}. Note that
  23114. resolving MAC addresses is only possible if the client is in the local
  23115. network or obtained a DHCP lease from dnsmasq.
  23116. @end table
  23117. @end deftp
  23118. @subsubheading ddclient Service
  23119. @cindex ddclient
  23120. The ddclient service described below runs the ddclient daemon, which takes
  23121. care of automatically updating DNS entries for service providers such as
  23122. @uref{https://dyn.com/dns/, Dyn}.
  23123. The following example show instantiates the service with its default
  23124. configuration:
  23125. @lisp
  23126. (service ddclient-service-type)
  23127. @end lisp
  23128. Note that ddclient needs to access credentials that are stored in a
  23129. @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
  23130. @code{secret-file} below). You are expected to create this file manually, in
  23131. an ``out-of-band'' fashion (you @emph{could} make this file part of the
  23132. service configuration, for instance by using @code{plain-file}, but it will be
  23133. world-readable @i{via} @file{/gnu/store}). See the examples in the
  23134. @file{share/ddclient} directory of the @code{ddclient} package.
  23135. @c %start of fragment
  23136. Available @code{ddclient-configuration} fields are:
  23137. @deftypevr {@code{ddclient-configuration} parameter} package ddclient
  23138. The ddclient package.
  23139. @end deftypevr
  23140. @deftypevr {@code{ddclient-configuration} parameter} integer daemon
  23141. The period after which ddclient will retry to check IP and domain name.
  23142. Defaults to @samp{300}.
  23143. @end deftypevr
  23144. @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
  23145. Use syslog for the output.
  23146. Defaults to @samp{#t}.
  23147. @end deftypevr
  23148. @deftypevr {@code{ddclient-configuration} parameter} string mail
  23149. Mail to user.
  23150. Defaults to @samp{"root"}.
  23151. @end deftypevr
  23152. @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
  23153. Mail failed update to user.
  23154. Defaults to @samp{"root"}.
  23155. @end deftypevr
  23156. @deftypevr {@code{ddclient-configuration} parameter} string pid
  23157. The ddclient PID file.
  23158. Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
  23159. @end deftypevr
  23160. @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
  23161. Enable SSL support.
  23162. Defaults to @samp{#t}.
  23163. @end deftypevr
  23164. @deftypevr {@code{ddclient-configuration} parameter} string user
  23165. Specifies the user name or ID that is used when running ddclient
  23166. program.
  23167. Defaults to @samp{"ddclient"}.
  23168. @end deftypevr
  23169. @deftypevr {@code{ddclient-configuration} parameter} string group
  23170. Group of the user who will run the ddclient program.
  23171. Defaults to @samp{"ddclient"}.
  23172. @end deftypevr
  23173. @deftypevr {@code{ddclient-configuration} parameter} string secret-file
  23174. Secret file which will be appended to @file{ddclient.conf} file. This
  23175. file contains credentials for use by ddclient. You are expected to
  23176. create it manually.
  23177. Defaults to @samp{"/etc/ddclient/secrets.conf"}.
  23178. @end deftypevr
  23179. @deftypevr {@code{ddclient-configuration} parameter} list extra-options
  23180. Extra options will be appended to @file{ddclient.conf} file.
  23181. Defaults to @samp{()}.
  23182. @end deftypevr
  23183. @c %end of fragment
  23184. @node VPN Services
  23185. @subsection VPN Services
  23186. @cindex VPN (virtual private network)
  23187. @cindex virtual private network (VPN)
  23188. The @code{(gnu services vpn)} module provides services related to
  23189. @dfn{virtual private networks} (VPNs).
  23190. @subsubheading Bitmask
  23191. @defvr {Scheme Variable} bitmask-service-type
  23192. A service type for the @uref{https://bitmask.net, Bitmask} VPN client. It makes
  23193. the client available in the system and loads its polkit policy. Please note that
  23194. the client expects an active polkit-agent, which is either run by your
  23195. desktop-environment or should be run manually.
  23196. @end defvr
  23197. @subsubheading OpenVPN
  23198. It provides a @emph{client} service for your machine to connect to a
  23199. VPN, and a @emph{server} service for your machine to host a VPN@.
  23200. @deffn {Scheme Procedure} openvpn-client-service @
  23201. [#:config (openvpn-client-configuration)]
  23202. Return a service that runs @command{openvpn}, a VPN daemon, as a client.
  23203. @end deffn
  23204. @deffn {Scheme Procedure} openvpn-server-service @
  23205. [#:config (openvpn-server-configuration)]
  23206. Return a service that runs @command{openvpn}, a VPN daemon, as a server.
  23207. Both can be run simultaneously.
  23208. @end deffn
  23209. @c %automatically generated documentation
  23210. Available @code{openvpn-client-configuration} fields are:
  23211. @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
  23212. The OpenVPN package.
  23213. @end deftypevr
  23214. @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
  23215. The OpenVPN pid file.
  23216. Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
  23217. @end deftypevr
  23218. @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
  23219. The protocol (UDP or TCP) used to open a channel between clients and
  23220. servers.
  23221. Defaults to @samp{udp}.
  23222. @end deftypevr
  23223. @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
  23224. The device type used to represent the VPN connection.
  23225. Defaults to @samp{tun}.
  23226. @end deftypevr
  23227. If you do not have some of these files (eg.@: you use a username and
  23228. password), you can disable any of the following three fields by setting
  23229. it to @code{'disabled}.
  23230. @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string ca
  23231. The certificate authority to check connections against.
  23232. Defaults to @samp{"/etc/openvpn/ca.crt"}.
  23233. @end deftypevr
  23234. @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string cert
  23235. The certificate of the machine the daemon is running on. It should be
  23236. signed by the authority given in @code{ca}.
  23237. Defaults to @samp{"/etc/openvpn/client.crt"}.
  23238. @end deftypevr
  23239. @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string key
  23240. The key of the machine the daemon is running on. It must be the key whose
  23241. certificate is @code{cert}.
  23242. Defaults to @samp{"/etc/openvpn/client.key"}.
  23243. @end deftypevr
  23244. @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
  23245. Whether to use the lzo compression algorithm.
  23246. Defaults to @samp{#t}.
  23247. @end deftypevr
  23248. @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
  23249. Don't re-read key files across SIGUSR1 or --ping-restart.
  23250. Defaults to @samp{#t}.
  23251. @end deftypevr
  23252. @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
  23253. Don't close and reopen TUN/TAP device or run up/down scripts across
  23254. SIGUSR1 or --ping-restart restarts.
  23255. Defaults to @samp{#t}.
  23256. @end deftypevr
  23257. @deftypevr {@code{openvpn-client-configuration} parameter} boolean fast-io?
  23258. (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
  23259. poll/epoll/select prior to the write operation.
  23260. Defaults to @samp{#f}.
  23261. @end deftypevr
  23262. @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
  23263. Verbosity level.
  23264. Defaults to @samp{3}.
  23265. @end deftypevr
  23266. @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
  23267. Add an additional layer of HMAC authentication on top of the TLS control
  23268. channel to protect against DoS attacks.
  23269. Defaults to @samp{#f}.
  23270. @end deftypevr
  23271. @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string auth-user-pass
  23272. Authenticate with server using username/password. The option is a file
  23273. containing username/password on 2 lines. Do not use a file-like object as it
  23274. would be added to the store and readable by any user.
  23275. Defaults to @samp{'disabled}.
  23276. @end deftypevr
  23277. @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
  23278. Whether to check the server certificate has server usage extension.
  23279. Defaults to @samp{#t}.
  23280. @end deftypevr
  23281. @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
  23282. Bind to a specific local port number.
  23283. Defaults to @samp{#f}.
  23284. @end deftypevr
  23285. @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
  23286. Retry resolving server address.
  23287. Defaults to @samp{#t}.
  23288. @end deftypevr
  23289. @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
  23290. A list of remote servers to connect to.
  23291. Defaults to @samp{()}.
  23292. Available @code{openvpn-remote-configuration} fields are:
  23293. @deftypevr {@code{openvpn-remote-configuration} parameter} string name
  23294. Server name.
  23295. Defaults to @samp{"my-server"}.
  23296. @end deftypevr
  23297. @deftypevr {@code{openvpn-remote-configuration} parameter} number port
  23298. Port number the server listens to.
  23299. Defaults to @samp{1194}.
  23300. @end deftypevr
  23301. @end deftypevr
  23302. @c %end of automatic openvpn-client documentation
  23303. @c %automatically generated documentation
  23304. Available @code{openvpn-server-configuration} fields are:
  23305. @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
  23306. The OpenVPN package.
  23307. @end deftypevr
  23308. @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
  23309. The OpenVPN pid file.
  23310. Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
  23311. @end deftypevr
  23312. @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
  23313. The protocol (UDP or TCP) used to open a channel between clients and
  23314. servers.
  23315. Defaults to @samp{udp}.
  23316. @end deftypevr
  23317. @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
  23318. The device type used to represent the VPN connection.
  23319. Defaults to @samp{tun}.
  23320. @end deftypevr
  23321. If you do not have some of these files (eg.@: you use a username and
  23322. password), you can disable any of the following three fields by setting
  23323. it to @code{'disabled}.
  23324. @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string ca
  23325. The certificate authority to check connections against.
  23326. Defaults to @samp{"/etc/openvpn/ca.crt"}.
  23327. @end deftypevr
  23328. @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string cert
  23329. The certificate of the machine the daemon is running on. It should be
  23330. signed by the authority given in @code{ca}.
  23331. Defaults to @samp{"/etc/openvpn/client.crt"}.
  23332. @end deftypevr
  23333. @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string key
  23334. The key of the machine the daemon is running on. It must be the key whose
  23335. certificate is @code{cert}.
  23336. Defaults to @samp{"/etc/openvpn/client.key"}.
  23337. @end deftypevr
  23338. @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
  23339. Whether to use the lzo compression algorithm.
  23340. Defaults to @samp{#t}.
  23341. @end deftypevr
  23342. @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
  23343. Don't re-read key files across SIGUSR1 or --ping-restart.
  23344. Defaults to @samp{#t}.
  23345. @end deftypevr
  23346. @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
  23347. Don't close and reopen TUN/TAP device or run up/down scripts across
  23348. SIGUSR1 or --ping-restart restarts.
  23349. Defaults to @samp{#t}.
  23350. @end deftypevr
  23351. @deftypevr {@code{openvpn-server-configuration} parameter} boolean fast-io?
  23352. (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
  23353. poll/epoll/select prior to the write operation.
  23354. Defaults to @samp{#f}.
  23355. @end deftypevr
  23356. @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
  23357. Verbosity level.
  23358. Defaults to @samp{3}.
  23359. @end deftypevr
  23360. @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
  23361. Add an additional layer of HMAC authentication on top of the TLS control
  23362. channel to protect against DoS attacks.
  23363. Defaults to @samp{#f}.
  23364. @end deftypevr
  23365. @deftypevr {@code{openvpn-server-configuration} parameter} number port
  23366. Specifies the port number on which the server listens.
  23367. Defaults to @samp{1194}.
  23368. @end deftypevr
  23369. @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
  23370. An ip and mask specifying the subnet inside the virtual network.
  23371. Defaults to @samp{"10.8.0.0 255.255.255.0"}.
  23372. @end deftypevr
  23373. @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
  23374. A CIDR notation specifying the IPv6 subnet inside the virtual network.
  23375. Defaults to @samp{#f}.
  23376. @end deftypevr
  23377. @deftypevr {@code{openvpn-server-configuration} parameter} string dh
  23378. The Diffie-Hellman parameters file.
  23379. Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
  23380. @end deftypevr
  23381. @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
  23382. The file that records client IPs.
  23383. Defaults to @samp{"/etc/openvpn/ipp.txt"}.
  23384. @end deftypevr
  23385. @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
  23386. When true, the server will act as a gateway for its clients.
  23387. Defaults to @samp{#f}.
  23388. @end deftypevr
  23389. @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
  23390. When true, clients are allowed to talk to each other inside the VPN.
  23391. Defaults to @samp{#f}.
  23392. @end deftypevr
  23393. @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
  23394. Causes ping-like messages to be sent back and forth over the link so
  23395. that each side knows when the other side has gone down. @code{keepalive}
  23396. requires a pair. The first element is the period of the ping sending,
  23397. and the second element is the timeout before considering the other side
  23398. down.
  23399. @end deftypevr
  23400. @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
  23401. The maximum number of clients.
  23402. Defaults to @samp{100}.
  23403. @end deftypevr
  23404. @deftypevr {@code{openvpn-server-configuration} parameter} string status
  23405. The status file. This file shows a small report on current connection.
  23406. It is truncated and rewritten every minute.
  23407. Defaults to @samp{"/var/run/openvpn/status"}.
  23408. @end deftypevr
  23409. @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
  23410. The list of configuration for some clients.
  23411. Defaults to @samp{()}.
  23412. Available @code{openvpn-ccd-configuration} fields are:
  23413. @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
  23414. Client name.
  23415. Defaults to @samp{"client"}.
  23416. @end deftypevr
  23417. @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
  23418. Client own network
  23419. Defaults to @samp{#f}.
  23420. @end deftypevr
  23421. @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
  23422. Client VPN IP.
  23423. Defaults to @samp{#f}.
  23424. @end deftypevr
  23425. @end deftypevr
  23426. @c %end of automatic openvpn-server documentation
  23427. @subheading strongSwan
  23428. Currently, the strongSwan service only provides legacy-style configuration with
  23429. @file{ipsec.conf} and @file{ipsec.secrets} files.
  23430. @defvr {Scheme Variable} strongswan-service-type
  23431. A service type for configuring strongSwan for IPsec @acronym{VPN,
  23432. Virtual Private Networking}. Its value must be a
  23433. @code{strongswan-configuration} record as in this example:
  23434. @lisp
  23435. (service strongswan-service-type
  23436. (strongswan-configuration
  23437. (ipsec-conf "/etc/ipsec.conf")
  23438. (ipsec-secrets "/etc/ipsec.secrets")))
  23439. @end lisp
  23440. @end defvr
  23441. @deftp {Data Type} strongswan-configuration
  23442. Data type representing the configuration of the StrongSwan service.
  23443. @table @asis
  23444. @item @code{strongswan}
  23445. The strongSwan package to use for this service.
  23446. @item @code{ipsec-conf} (default: @code{#f})
  23447. The file name of your @file{ipsec.conf}. If not @code{#f}, then this and
  23448. @code{ipsec-secrets} must both be strings.
  23449. @item @code{ipsec-secrets} (default @code{#f})
  23450. The file name of your @file{ipsec.secrets}. If not @code{#f}, then this and
  23451. @code{ipsec-conf} must both be strings.
  23452. @end table
  23453. @end deftp
  23454. @subsubheading Wireguard
  23455. @defvr {Scheme Variable} wireguard-service-type
  23456. A service type for a Wireguard tunnel interface. Its value must be a
  23457. @code{wireguard-configuration} record as in this example:
  23458. @lisp
  23459. (service wireguard-service-type
  23460. (wireguard-configuration
  23461. (peers
  23462. (list
  23463. (wireguard-peer
  23464. (name "my-peer")
  23465. (endpoint "my.wireguard.com:51820")
  23466. (public-key "hzpKg9X1yqu1axN6iJp0mWf6BZGo8m1wteKwtTmDGF4=")
  23467. (allowed-ips '("10.0.0.2/32")))))))
  23468. @end lisp
  23469. @end defvr
  23470. @deftp {Data Type} wireguard-configuration
  23471. Data type representing the configuration of the Wireguard service.
  23472. @table @asis
  23473. @item @code{wireguard}
  23474. The wireguard package to use for this service.
  23475. @item @code{interface} (default: @code{"wg0"})
  23476. The interface name for the VPN.
  23477. @item @code{addresses} (default: @code{'("10.0.0.1/32")})
  23478. The IP addresses to be assigned to the above interface.
  23479. @item @code{port} (default: @code{51820})
  23480. The port on which to listen for incoming connections.
  23481. @item @code{dns} (default: @code{#f})
  23482. The DNS server(s) to announce to VPN clients via DHCP.
  23483. @item @code{private-key} (default: @code{"/etc/wireguard/private.key"})
  23484. The private key file for the interface. It is automatically generated if
  23485. the file does not exist.
  23486. @item @code{peers} (default: @code{'()})
  23487. The authorized peers on this interface. This is a list of
  23488. @var{wireguard-peer} records.
  23489. @end table
  23490. @end deftp
  23491. @deftp {Data Type} wireguard-peer
  23492. Data type representing a Wireguard peer attached to a given interface.
  23493. @table @asis
  23494. @item @code{name}
  23495. The peer name.
  23496. @item @code{endpoint} (default: @code{#f})
  23497. The optional endpoint for the peer, such as
  23498. @code{"demo.wireguard.com:51820"}.
  23499. @item @code{public-key}
  23500. The peer public-key represented as a base64 string.
  23501. @item @code{allowed-ips}
  23502. A list of IP addresses from which incoming traffic for this peer is
  23503. allowed and to which incoming traffic for this peer is directed.
  23504. @item @code{keep-alive} (default: @code{#f})
  23505. An optional time interval in seconds. A packet will be sent to the
  23506. server endpoint once per time interval. This helps receiving
  23507. incoming connections from this peer when you are behind a NAT or
  23508. a firewall.
  23509. @end table
  23510. @end deftp
  23511. @node Network File System
  23512. @subsection Network File System
  23513. @cindex NFS
  23514. The @code{(gnu services nfs)} module provides the following services,
  23515. which are most commonly used in relation to mounting or exporting
  23516. directory trees as @dfn{network file systems} (NFS).
  23517. While it is possible to use the individual components that together make
  23518. up a Network File System service, we recommended to configure an NFS
  23519. server with the @code{nfs-service-type}.
  23520. @subsubheading NFS Service
  23521. @cindex NFS, server
  23522. The NFS service takes care of setting up all NFS component services,
  23523. kernel configuration file systems, and installs configuration files in
  23524. the locations that NFS expects.
  23525. @defvr {Scheme Variable} nfs-service-type
  23526. A service type for a complete NFS server.
  23527. @end defvr
  23528. @deftp {Data Type} nfs-configuration
  23529. This data type represents the configuration of the NFS service and all
  23530. of its subsystems.
  23531. It has the following parameters:
  23532. @table @asis
  23533. @item @code{nfs-utils} (default: @code{nfs-utils})
  23534. The nfs-utils package to use.
  23535. @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
  23536. If a list of string values is provided, the @command{rpc.nfsd} daemon
  23537. will be limited to supporting the given versions of the NFS protocol.
  23538. @item @code{exports} (default: @code{'()})
  23539. This is a list of directories the NFS server should export. Each entry
  23540. is a list consisting of two elements: a directory name and a string
  23541. containing all options. This is an example in which the directory
  23542. @file{/export} is served to all NFS clients as a read-only share:
  23543. @lisp
  23544. (nfs-configuration
  23545. (exports
  23546. '(("/export"
  23547. "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
  23548. @end lisp
  23549. @item @code{rpcmountd-port} (default: @code{#f})
  23550. The network port that the @command{rpc.mountd} daemon should use.
  23551. @item @code{rpcstatd-port} (default: @code{#f})
  23552. The network port that the @command{rpc.statd} daemon should use.
  23553. @item @code{rpcbind} (default: @code{rpcbind})
  23554. The rpcbind package to use.
  23555. @item @code{idmap-domain} (default: @code{"localdomain"})
  23556. The local NFSv4 domain name.
  23557. @item @code{nfsd-port} (default: @code{2049})
  23558. The network port that the @command{nfsd} daemon should use.
  23559. @item @code{nfsd-threads} (default: @code{8})
  23560. The number of threads used by the @command{nfsd} daemon.
  23561. @item @code{nfsd-tcp?} (default: @code{#t})
  23562. Whether the @command{nfsd} daemon should listen on a TCP socket.
  23563. @item @code{nfsd-udp?} (default: @code{#f})
  23564. Whether the @command{nfsd} daemon should listen on a UDP socket.
  23565. @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
  23566. The directory where the pipefs file system is mounted.
  23567. @item @code{debug} (default: @code{'()"})
  23568. A list of subsystems for which debugging output should be enabled. This
  23569. is a list of symbols. Any of these symbols are valid: @code{nfsd},
  23570. @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
  23571. @end table
  23572. @end deftp
  23573. If you don't need a complete NFS service or prefer to build it yourself
  23574. you can use the individual component services that are documented below.
  23575. @subsubheading RPC Bind Service
  23576. @cindex rpcbind
  23577. The RPC Bind service provides a facility to map program numbers into
  23578. universal addresses.
  23579. Many NFS related services use this facility. Hence it is automatically
  23580. started when a dependent service starts.
  23581. @defvr {Scheme Variable} rpcbind-service-type
  23582. A service type for the RPC portmapper daemon.
  23583. @end defvr
  23584. @deftp {Data Type} rpcbind-configuration
  23585. Data type representing the configuration of the RPC Bind Service.
  23586. This type has the following parameters:
  23587. @table @asis
  23588. @item @code{rpcbind} (default: @code{rpcbind})
  23589. The rpcbind package to use.
  23590. @item @code{warm-start?} (default: @code{#t})
  23591. If this parameter is @code{#t}, then the daemon will read a
  23592. state file on startup thus reloading state information saved by a previous
  23593. instance.
  23594. @end table
  23595. @end deftp
  23596. @subsubheading Pipefs Pseudo File System
  23597. @cindex pipefs
  23598. @cindex rpc_pipefs
  23599. The pipefs file system is used to transfer NFS related data
  23600. between the kernel and user space programs.
  23601. @defvr {Scheme Variable} pipefs-service-type
  23602. A service type for the pipefs pseudo file system.
  23603. @end defvr
  23604. @deftp {Data Type} pipefs-configuration
  23605. Data type representing the configuration of the pipefs pseudo file system service.
  23606. This type has the following parameters:
  23607. @table @asis
  23608. @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
  23609. The directory to which the file system is to be attached.
  23610. @end table
  23611. @end deftp
  23612. @subsubheading GSS Daemon Service
  23613. @cindex GSSD
  23614. @cindex GSS
  23615. @cindex global security system
  23616. The @dfn{global security system} (GSS) daemon provides strong security for RPC
  23617. based protocols.
  23618. Before exchanging RPC requests an RPC client must establish a security
  23619. context. Typically this is done using the Kerberos command @command{kinit}
  23620. or automatically at login time using PAM services (@pxref{Kerberos Services}).
  23621. @defvr {Scheme Variable} gss-service-type
  23622. A service type for the Global Security System (GSS) daemon.
  23623. @end defvr
  23624. @deftp {Data Type} gss-configuration
  23625. Data type representing the configuration of the GSS daemon service.
  23626. This type has the following parameters:
  23627. @table @asis
  23628. @item @code{nfs-utils} (default: @code{nfs-utils})
  23629. The package in which the @command{rpc.gssd} command is to be found.
  23630. @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
  23631. The directory where the pipefs file system is mounted.
  23632. @end table
  23633. @end deftp
  23634. @subsubheading IDMAP Daemon Service
  23635. @cindex idmapd
  23636. @cindex name mapper
  23637. The idmap daemon service provides mapping between user IDs and user names.
  23638. Typically it is required in order to access file systems mounted via NFSv4.
  23639. @defvr {Scheme Variable} idmap-service-type
  23640. A service type for the Identity Mapper (IDMAP) daemon.
  23641. @end defvr
  23642. @deftp {Data Type} idmap-configuration
  23643. Data type representing the configuration of the IDMAP daemon service.
  23644. This type has the following parameters:
  23645. @table @asis
  23646. @item @code{nfs-utils} (default: @code{nfs-utils})
  23647. The package in which the @command{rpc.idmapd} command is to be found.
  23648. @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
  23649. The directory where the pipefs file system is mounted.
  23650. @item @code{domain} (default: @code{#f})
  23651. The local NFSv4 domain name.
  23652. This must be a string or @code{#f}.
  23653. If it is @code{#f} then the daemon will use the host's fully qualified domain name.
  23654. @item @code{verbosity} (default: @code{0})
  23655. The verbosity level of the daemon.
  23656. @end table
  23657. @end deftp
  23658. @node Continuous Integration
  23659. @subsection Continuous Integration
  23660. @cindex continuous integration
  23661. @uref{https://guix.gnu.org/cuirass/, Cuirass} is a continuous
  23662. integration tool for Guix. It can be used both for development and for
  23663. providing substitutes to others (@pxref{Substitutes}).
  23664. The @code{(gnu services cuirass)} module provides the following service.
  23665. @defvr {Scheme Procedure} cuirass-service-type
  23666. The type of the Cuirass service. Its value must be a
  23667. @code{cuirass-configuration} object, as described below.
  23668. @end defvr
  23669. To add build jobs, you have to set the @code{specifications} field of
  23670. the configuration. For instance, the following example will build all
  23671. the packages provided by the @code{my-channel} channel.
  23672. @lisp
  23673. (define %cuirass-specs
  23674. #~(list (specification
  23675. (name "my-channel")
  23676. (build '(channels my-channel))
  23677. (channels
  23678. (cons (channel
  23679. (name 'my-channel)
  23680. (url "https://my-channel.git"))
  23681. %default-channels)))))
  23682. (service cuirass-service-type
  23683. (cuirass-configuration
  23684. (specifications %cuirass-specs)))
  23685. @end lisp
  23686. To build the @code{linux-libre} package defined by the default Guix
  23687. channel, one can use the following configuration.
  23688. @lisp
  23689. (define %cuirass-specs
  23690. #~(list (specification
  23691. (name "my-linux")
  23692. (build '(packages "linux-libre")))))
  23693. (service cuirass-service-type
  23694. (cuirass-configuration
  23695. (specifications %cuirass-specs)))
  23696. @end lisp
  23697. The other configuration possibilities, as well as the specification
  23698. record itself are described in the Cuirass manual
  23699. (@pxref{Specifications,,, cuirass, Cuirass}).
  23700. While information related to build jobs is located directly in the
  23701. specifications, global settings for the @command{cuirass} process are
  23702. accessible in other @code{cuirass-configuration} fields.
  23703. @deftp {Data Type} cuirass-configuration
  23704. Data type representing the configuration of Cuirass.
  23705. @table @asis
  23706. @item @code{cuirass} (default: @code{cuirass})
  23707. The Cuirass package to use.
  23708. @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
  23709. Location of the log file.
  23710. @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
  23711. Location of the log file used by the web interface.
  23712. @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
  23713. Location of the repository cache.
  23714. @item @code{user} (default: @code{"cuirass"})
  23715. Owner of the @code{cuirass} process.
  23716. @item @code{group} (default: @code{"cuirass"})
  23717. Owner's group of the @code{cuirass} process.
  23718. @item @code{interval} (default: @code{60})
  23719. Number of seconds between the poll of the repositories followed by the
  23720. Cuirass jobs.
  23721. @item @code{parameters} (default: @code{#f})
  23722. Read parameters from the given @var{parameters} file. The supported
  23723. parameters are described here (@pxref{Parameters,,, cuirass, Cuirass}).
  23724. @item @code{remote-server} (default: @code{#f})
  23725. A @code{cuirass-remote-server-configuration} record to use the build
  23726. remote mechanism or @code{#f} to use the default build mechanism.
  23727. @item @code{database} (default: @code{"dbname=cuirass host=/var/run/postgresql"})
  23728. Use @var{database} as the database containing the jobs and the past
  23729. build results. Since Cuirass uses PostgreSQL as a database engine,
  23730. @var{database} must be a string such as @code{"dbname=cuirass
  23731. host=localhost"}.
  23732. @item @code{port} (default: @code{8081})
  23733. Port number used by the HTTP server.
  23734. @item @code{host} (default: @code{"localhost"})
  23735. Listen on the network interface for @var{host}. The default is to
  23736. accept connections from localhost.
  23737. @item @code{specifications} (default: @code{#~'()})
  23738. A gexp (@pxref{G-Expressions}) that evaluates to a list of
  23739. specifications records. The specification record is described in the
  23740. Cuirass manual (@pxref{Specifications,,, cuirass, Cuirass}).
  23741. @item @code{use-substitutes?} (default: @code{#f})
  23742. This allows using substitutes to avoid building every dependencies of a job
  23743. from source.
  23744. @item @code{one-shot?} (default: @code{#f})
  23745. Only evaluate specifications and build derivations once.
  23746. @item @code{fallback?} (default: @code{#f})
  23747. When substituting a pre-built binary fails, fall back to building
  23748. packages locally.
  23749. @item @code{extra-options} (default: @code{'()})
  23750. Extra options to pass when running the Cuirass processes.
  23751. @end table
  23752. @end deftp
  23753. @cindex remote build
  23754. @subsubheading Cuirass remote building
  23755. Cuirass supports two mechanisms to build derivations.
  23756. @itemize
  23757. @item Using the local Guix daemon.
  23758. This is the default build mechanism. Once the build jobs are
  23759. evaluated, they are sent to the local Guix daemon. Cuirass then
  23760. listens to the Guix daemon output to detect the various build events.
  23761. @item Using the remote build mechanism.
  23762. The build jobs are not submitted to the local Guix daemon. Instead, a
  23763. remote server dispatches build requests to the connect remote workers,
  23764. according to the build priorities.
  23765. @end itemize
  23766. To enable this build mode a @code{cuirass-remote-server-configuration}
  23767. record must be passed as @code{remote-server} argument of the
  23768. @code{cuirass-configuration} record. The
  23769. @code{cuirass-remote-server-configuration} record is described below.
  23770. This build mode scales way better than the default build mode. This is
  23771. the build mode that is used on the GNU Guix build farm at
  23772. @url{https://ci.guix.gnu.org}. It should be preferred when using
  23773. Cuirass to build large amount of packages.
  23774. @deftp {Data Type} cuirass-remote-server-configuration
  23775. Data type representing the configuration of the Cuirass remote-server.
  23776. @table @asis
  23777. @item @code{backend-port} (default: @code{5555})
  23778. The TCP port for communicating with @code{remote-worker} processes
  23779. using ZMQ. It defaults to @code{5555}.
  23780. @item @code{log-port} (default: @code{5556})
  23781. The TCP port of the log server. It defaults to @code{5556}.
  23782. @item @code{publish-port} (default: @code{5557})
  23783. The TCP port of the publish server. It defaults to @code{5557}.
  23784. @item @code{log-file} (default: @code{"/var/log/cuirass-remote-server.log"})
  23785. Location of the log file.
  23786. @item @code{cache} (default: @code{"/var/cache/cuirass/remote"})
  23787. Use @var{cache} directory to cache build log files.
  23788. @item @code{trigger-url} (default: @code{#f})
  23789. Once a substitute is successfully fetched, trigger substitute baking at
  23790. @var{trigger-url}.
  23791. @item @code{publish?} (default: @code{#t})
  23792. If set to false, do not start a publish server and ignore the
  23793. @code{publish-port} argument. This can be useful if there is already a
  23794. standalone publish server standing next to the remote server.
  23795. @item @code{public-key}
  23796. @item @code{private-key}
  23797. Use the specific @var{file}s as the public/private key pair used to sign
  23798. the store items being published.
  23799. @end table
  23800. @end deftp
  23801. At least one remote worker must also be started on any machine of the
  23802. local network to actually perform the builds and report their status.
  23803. @deftp {Data Type} cuirass-remote-worker-configuration
  23804. Data type representing the configuration of the Cuirass remote-worker.
  23805. @table @asis
  23806. @item @code{cuirass} (default: @code{cuirass})
  23807. The Cuirass package to use.
  23808. @item @code{workers} (default: @code{1})
  23809. Start @var{workers} parallel workers.
  23810. @item @code{server} (default: @code{#f})
  23811. Do not use Avahi discovery and connect to the given @code{server} IP
  23812. address instead.
  23813. @item @code{systems} (default: @code{(list (%current-system))})
  23814. Only request builds for the given @var{systems}.
  23815. @item @code{log-file} (default: @code{"/var/log/cuirass-remote-worker.log"})
  23816. Location of the log file.
  23817. @item @code{publish-port} (default: @code{5558})
  23818. The TCP port of the publish server. It defaults to @code{5558}.
  23819. @item @code{substitute-urls} (default: @code{%default-substitute-urls})
  23820. The list of URLs where to look for substitutes by default.
  23821. @item @code{public-key}
  23822. @item @code{private-key}
  23823. Use the specific @var{file}s as the public/private key pair used to sign
  23824. the store items being published.
  23825. @end table
  23826. @end deftp
  23827. @subsubheading Laminar
  23828. @uref{https://laminar.ohwg.net/, Laminar} is a lightweight and modular
  23829. Continuous Integration service. It doesn't have a configuration web UI
  23830. instead uses version-controllable configuration files and scripts.
  23831. Laminar encourages the use of existing tools such as bash and cron
  23832. instead of reinventing them.
  23833. @defvr {Scheme Procedure} laminar-service-type
  23834. The type of the Laminar service. Its value must be a
  23835. @code{laminar-configuration} object, as described below.
  23836. All configuration values have defaults, a minimal configuration to get
  23837. Laminar running is shown below. By default, the web interface is
  23838. available on port 8080.
  23839. @lisp
  23840. (service laminar-service-type)
  23841. @end lisp
  23842. @end defvr
  23843. @deftp {Data Type} laminar-configuration
  23844. Data type representing the configuration of Laminar.
  23845. @table @asis
  23846. @item @code{laminar} (default: @code{laminar})
  23847. The Laminar package to use.
  23848. @item @code{home-directory} (default: @code{"/var/lib/laminar"})
  23849. The directory for job configurations and run directories.
  23850. @item @code{bind-http} (default: @code{"*:8080"})
  23851. The interface/port or unix socket on which laminard should listen for
  23852. incoming connections to the web frontend.
  23853. @item @code{bind-rpc} (default: @code{"unix-abstract:laminar"})
  23854. The interface/port or unix socket on which laminard should listen for
  23855. incoming commands such as build triggers.
  23856. @item @code{title} (default: @code{"Laminar"})
  23857. The page title to show in the web frontend.
  23858. @item @code{keep-rundirs} (default: @code{0})
  23859. Set to an integer defining how many rundirs to keep per job. The
  23860. lowest-numbered ones will be deleted. The default is 0, meaning all run
  23861. dirs will be immediately deleted.
  23862. @item @code{archive-url} (default: @code{#f})
  23863. The web frontend served by laminard will use this URL to form links to
  23864. artefacts archived jobs.
  23865. @item @code{base-url} (default: @code{#f})
  23866. Base URL to use for links to laminar itself.
  23867. @end table
  23868. @end deftp
  23869. @node Power Management Services
  23870. @subsection Power Management Services
  23871. @cindex tlp
  23872. @cindex power management with TLP
  23873. @subsubheading TLP daemon
  23874. The @code{(gnu services pm)} module provides a Guix service definition
  23875. for the Linux power management tool TLP.
  23876. TLP enables various powersaving modes in userspace and kernel.
  23877. Contrary to @code{upower-service}, it is not a passive,
  23878. monitoring tool, as it will apply custom settings each time a new power
  23879. source is detected. More information can be found at
  23880. @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
  23881. @deffn {Scheme Variable} tlp-service-type
  23882. The service type for the TLP tool. The default settings are optimised
  23883. for battery life on most systems, but you can tweak them to your heart's
  23884. content by adding a valid @code{tlp-configuration}:
  23885. @lisp
  23886. (service tlp-service-type
  23887. (tlp-configuration
  23888. (cpu-scaling-governor-on-ac (list "performance"))
  23889. (sched-powersave-on-bat? #t)))
  23890. @end lisp
  23891. @end deffn
  23892. Each parameter definition is preceded by its type; for example,
  23893. @samp{boolean foo} indicates that the @code{foo} parameter
  23894. should be specified as a boolean. Types starting with
  23895. @code{maybe-} denote parameters that won't show up in TLP config file
  23896. when their value is @code{'disabled}.
  23897. @c The following documentation was initially generated by
  23898. @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
  23899. @c documentation is better, so we shouldn't hesitate to edit below as
  23900. @c needed. However if the change you want to make to this documentation
  23901. @c can be done in an automated way, it's probably easier to change
  23902. @c (generate-documentation) than to make it below and have to deal with
  23903. @c the churn as TLP updates.
  23904. Available @code{tlp-configuration} fields are:
  23905. @deftypevr {@code{tlp-configuration} parameter} package tlp
  23906. The TLP package.
  23907. @end deftypevr
  23908. @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
  23909. Set to true if you wish to enable TLP.
  23910. Defaults to @samp{#t}.
  23911. @end deftypevr
  23912. @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
  23913. Default mode when no power supply can be detected. Alternatives are AC
  23914. and BAT.
  23915. Defaults to @samp{"AC"}.
  23916. @end deftypevr
  23917. @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
  23918. Number of seconds Linux kernel has to wait after the disk goes idle,
  23919. before syncing on AC.
  23920. Defaults to @samp{0}.
  23921. @end deftypevr
  23922. @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
  23923. Same as @code{disk-idle-ac} but on BAT mode.
  23924. Defaults to @samp{2}.
  23925. @end deftypevr
  23926. @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
  23927. Dirty pages flushing periodicity, expressed in seconds.
  23928. Defaults to @samp{15}.
  23929. @end deftypevr
  23930. @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
  23931. Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
  23932. Defaults to @samp{60}.
  23933. @end deftypevr
  23934. @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
  23935. CPU frequency scaling governor on AC mode. With intel_pstate driver,
  23936. alternatives are powersave and performance. With acpi-cpufreq driver,
  23937. alternatives are ondemand, powersave, performance and conservative.
  23938. Defaults to @samp{disabled}.
  23939. @end deftypevr
  23940. @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
  23941. Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
  23942. Defaults to @samp{disabled}.
  23943. @end deftypevr
  23944. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
  23945. Set the min available frequency for the scaling governor on AC.
  23946. Defaults to @samp{disabled}.
  23947. @end deftypevr
  23948. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
  23949. Set the max available frequency for the scaling governor on AC.
  23950. Defaults to @samp{disabled}.
  23951. @end deftypevr
  23952. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
  23953. Set the min available frequency for the scaling governor on BAT.
  23954. Defaults to @samp{disabled}.
  23955. @end deftypevr
  23956. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
  23957. Set the max available frequency for the scaling governor on BAT.
  23958. Defaults to @samp{disabled}.
  23959. @end deftypevr
  23960. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
  23961. Limit the min P-state to control the power dissipation of the CPU, in AC
  23962. mode. Values are stated as a percentage of the available performance.
  23963. Defaults to @samp{disabled}.
  23964. @end deftypevr
  23965. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
  23966. Limit the max P-state to control the power dissipation of the CPU, in AC
  23967. mode. Values are stated as a percentage of the available performance.
  23968. Defaults to @samp{disabled}.
  23969. @end deftypevr
  23970. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
  23971. Same as @code{cpu-min-perf-on-ac} on BAT mode.
  23972. Defaults to @samp{disabled}.
  23973. @end deftypevr
  23974. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
  23975. Same as @code{cpu-max-perf-on-ac} on BAT mode.
  23976. Defaults to @samp{disabled}.
  23977. @end deftypevr
  23978. @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
  23979. Enable CPU turbo boost feature on AC mode.
  23980. Defaults to @samp{disabled}.
  23981. @end deftypevr
  23982. @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
  23983. Same as @code{cpu-boost-on-ac?} on BAT mode.
  23984. Defaults to @samp{disabled}.
  23985. @end deftypevr
  23986. @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
  23987. Allow Linux kernel to minimize the number of CPU cores/hyper-threads
  23988. used under light load conditions.
  23989. Defaults to @samp{#f}.
  23990. @end deftypevr
  23991. @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
  23992. Same as @code{sched-powersave-on-ac?} but on BAT mode.
  23993. Defaults to @samp{#t}.
  23994. @end deftypevr
  23995. @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
  23996. Enable Linux kernel NMI watchdog.
  23997. Defaults to @samp{#f}.
  23998. @end deftypevr
  23999. @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
  24000. For Linux kernels with PHC patch applied, change CPU voltages. An
  24001. example value would be @samp{"F:V F:V F:V F:V"}.
  24002. Defaults to @samp{disabled}.
  24003. @end deftypevr
  24004. @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
  24005. Set CPU performance versus energy saving policy on AC@. Alternatives are
  24006. performance, normal, powersave.
  24007. Defaults to @samp{"performance"}.
  24008. @end deftypevr
  24009. @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
  24010. Same as @code{energy-perf-policy-ac} but on BAT mode.
  24011. Defaults to @samp{"powersave"}.
  24012. @end deftypevr
  24013. @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
  24014. Hard disk devices.
  24015. @end deftypevr
  24016. @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
  24017. Hard disk advanced power management level.
  24018. @end deftypevr
  24019. @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
  24020. Same as @code{disk-apm-bat} but on BAT mode.
  24021. @end deftypevr
  24022. @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
  24023. Hard disk spin down timeout. One value has to be specified for each
  24024. declared hard disk.
  24025. Defaults to @samp{disabled}.
  24026. @end deftypevr
  24027. @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
  24028. Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
  24029. Defaults to @samp{disabled}.
  24030. @end deftypevr
  24031. @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
  24032. Select IO scheduler for disk devices. One value has to be specified for
  24033. each declared hard disk. Example alternatives are cfq, deadline and
  24034. noop.
  24035. Defaults to @samp{disabled}.
  24036. @end deftypevr
  24037. @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
  24038. SATA aggressive link power management (ALPM) level. Alternatives are
  24039. min_power, medium_power, max_performance.
  24040. Defaults to @samp{"max_performance"}.
  24041. @end deftypevr
  24042. @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
  24043. Same as @code{sata-linkpwr-ac} but on BAT mode.
  24044. Defaults to @samp{"min_power"}.
  24045. @end deftypevr
  24046. @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
  24047. Exclude specified SATA host devices for link power management.
  24048. Defaults to @samp{disabled}.
  24049. @end deftypevr
  24050. @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
  24051. Enable Runtime Power Management for AHCI controller and disks on AC
  24052. mode.
  24053. Defaults to @samp{disabled}.
  24054. @end deftypevr
  24055. @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
  24056. Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
  24057. Defaults to @samp{disabled}.
  24058. @end deftypevr
  24059. @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
  24060. Seconds of inactivity before disk is suspended.
  24061. Defaults to @samp{15}.
  24062. @end deftypevr
  24063. @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
  24064. PCI Express Active State Power Management level. Alternatives are
  24065. default, performance, powersave.
  24066. Defaults to @samp{"performance"}.
  24067. @end deftypevr
  24068. @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
  24069. Same as @code{pcie-aspm-ac} but on BAT mode.
  24070. Defaults to @samp{"powersave"}.
  24071. @end deftypevr
  24072. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer start-charge-thresh-bat0
  24073. Percentage when battery 0 should begin charging. Only supported on some laptops.
  24074. Defaults to @samp{disabled}.
  24075. @end deftypevr
  24076. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer stop-charge-thresh-bat0
  24077. Percentage when battery 0 should stop charging. Only supported on some laptops.
  24078. Defaults to @samp{disabled}.
  24079. @end deftypevr
  24080. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer start-charge-thresh-bat1
  24081. Percentage when battery 1 should begin charging. Only supported on some laptops.
  24082. Defaults to @samp{disabled}.
  24083. @end deftypevr
  24084. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer stop-charge-thresh-bat1
  24085. Percentage when battery 1 should stop charging. Only supported on some laptops.
  24086. Defaults to @samp{disabled}.
  24087. @end deftypevr
  24088. @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
  24089. Radeon graphics clock speed level. Alternatives are low, mid, high,
  24090. auto, default.
  24091. Defaults to @samp{"high"}.
  24092. @end deftypevr
  24093. @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
  24094. Same as @code{radeon-power-ac} but on BAT mode.
  24095. Defaults to @samp{"low"}.
  24096. @end deftypevr
  24097. @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
  24098. Radeon dynamic power management method (DPM). Alternatives are battery,
  24099. performance.
  24100. Defaults to @samp{"performance"}.
  24101. @end deftypevr
  24102. @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
  24103. Same as @code{radeon-dpm-state-ac} but on BAT mode.
  24104. Defaults to @samp{"battery"}.
  24105. @end deftypevr
  24106. @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
  24107. Radeon DPM performance level. Alternatives are auto, low, high.
  24108. Defaults to @samp{"auto"}.
  24109. @end deftypevr
  24110. @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
  24111. Same as @code{radeon-dpm-perf-ac} but on BAT mode.
  24112. Defaults to @samp{"auto"}.
  24113. @end deftypevr
  24114. @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
  24115. Wifi power saving mode.
  24116. Defaults to @samp{#f}.
  24117. @end deftypevr
  24118. @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
  24119. Same as @code{wifi-power-ac?} but on BAT mode.
  24120. Defaults to @samp{#t}.
  24121. @end deftypevr
  24122. @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
  24123. Disable wake on LAN.
  24124. Defaults to @samp{#t}.
  24125. @end deftypevr
  24126. @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
  24127. Timeout duration in seconds before activating audio power saving on
  24128. Intel HDA and AC97 devices. A value of 0 disables power saving.
  24129. Defaults to @samp{0}.
  24130. @end deftypevr
  24131. @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
  24132. Same as @code{sound-powersave-ac} but on BAT mode.
  24133. Defaults to @samp{1}.
  24134. @end deftypevr
  24135. @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
  24136. Disable controller in powersaving mode on Intel HDA devices.
  24137. Defaults to @samp{#t}.
  24138. @end deftypevr
  24139. @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
  24140. Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
  24141. powered on again by releasing (and reinserting) the eject lever or by
  24142. pressing the disc eject button on newer models.
  24143. Defaults to @samp{#f}.
  24144. @end deftypevr
  24145. @deftypevr {@code{tlp-configuration} parameter} string bay-device
  24146. Name of the optical drive device to power off.
  24147. Defaults to @samp{"sr0"}.
  24148. @end deftypevr
  24149. @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
  24150. Runtime Power Management for PCI(e) bus devices. Alternatives are on
  24151. and auto.
  24152. Defaults to @samp{"on"}.
  24153. @end deftypevr
  24154. @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
  24155. Same as @code{runtime-pm-ac} but on BAT mode.
  24156. Defaults to @samp{"auto"}.
  24157. @end deftypevr
  24158. @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
  24159. Runtime Power Management for all PCI(e) bus devices, except blacklisted
  24160. ones.
  24161. Defaults to @samp{#t}.
  24162. @end deftypevr
  24163. @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
  24164. Exclude specified PCI(e) device addresses from Runtime Power Management.
  24165. Defaults to @samp{disabled}.
  24166. @end deftypevr
  24167. @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
  24168. Exclude PCI(e) devices assigned to the specified drivers from Runtime
  24169. Power Management.
  24170. @end deftypevr
  24171. @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
  24172. Enable USB autosuspend feature.
  24173. Defaults to @samp{#t}.
  24174. @end deftypevr
  24175. @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
  24176. Exclude specified devices from USB autosuspend.
  24177. Defaults to @samp{disabled}.
  24178. @end deftypevr
  24179. @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
  24180. Exclude WWAN devices from USB autosuspend.
  24181. Defaults to @samp{#t}.
  24182. @end deftypevr
  24183. @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
  24184. Include specified devices into USB autosuspend, even if they are already
  24185. excluded by the driver or via @code{usb-blacklist-wwan?}.
  24186. Defaults to @samp{disabled}.
  24187. @end deftypevr
  24188. @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
  24189. Enable USB autosuspend before shutdown.
  24190. Defaults to @samp{disabled}.
  24191. @end deftypevr
  24192. @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
  24193. Restore radio device state (bluetooth, wifi, wwan) from previous
  24194. shutdown on system startup.
  24195. Defaults to @samp{#f}.
  24196. @end deftypevr
  24197. @cindex thermald
  24198. @cindex CPU frequency scaling with thermald
  24199. @subsubheading Thermald daemon
  24200. The @code{(gnu services pm)} module provides an interface to
  24201. thermald, a CPU frequency scaling service which helps prevent overheating.
  24202. @defvr {Scheme Variable} thermald-service-type
  24203. This is the service type for
  24204. @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
  24205. Thermal Daemon, which is responsible for controlling the thermal state
  24206. of processors and preventing overheating.
  24207. @end defvr
  24208. @deftp {Data Type} thermald-configuration
  24209. Data type representing the configuration of @code{thermald-service-type}.
  24210. @table @asis
  24211. @item @code{adaptive?} (default: @code{#f})
  24212. Use @acronym{DPTF, Dynamic Power and Thermal Framework} adaptive tables
  24213. when present.
  24214. @item @code{ignore-cpuid-check?} (default: @code{#f})
  24215. Ignore cpuid check for supported CPU models.
  24216. @item @code{thermald} (default: @var{thermald})
  24217. Package object of thermald.
  24218. @end table
  24219. @end deftp
  24220. @node Audio Services
  24221. @subsection Audio Services
  24222. The @code{(gnu services audio)} module provides a service to start MPD
  24223. (the Music Player Daemon).
  24224. @cindex mpd
  24225. @subsubheading Music Player Daemon
  24226. The Music Player Daemon (MPD) is a service that can play music while
  24227. being controlled from the local machine or over the network by a variety
  24228. of clients.
  24229. The following example shows how one might run @code{mpd} as user
  24230. @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
  24231. @lisp
  24232. (service mpd-service-type
  24233. (mpd-configuration
  24234. (user "bob")
  24235. (port "6666")))
  24236. @end lisp
  24237. @defvr {Scheme Variable} mpd-service-type
  24238. The service type for @command{mpd}
  24239. @end defvr
  24240. @deftp {Data Type} mpd-configuration
  24241. Data type representing the configuration of @command{mpd}.
  24242. @table @asis
  24243. @item @code{user} (default: @code{"mpd"})
  24244. The user to run mpd as.
  24245. @item @code{music-dir} (default: @code{"~/Music"})
  24246. The directory to scan for music files.
  24247. @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
  24248. The directory to store playlists.
  24249. @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
  24250. The location of the music database.
  24251. @item @code{state-file} (default: @code{"~/.mpd/state"})
  24252. The location of the file that stores current MPD's state.
  24253. @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
  24254. The location of the sticker database.
  24255. @item @code{port} (default: @code{"6600"})
  24256. The port to run mpd on.
  24257. @item @code{address} (default: @code{"any"})
  24258. The address that mpd will bind to. To use a Unix domain socket,
  24259. an absolute path can be specified here.
  24260. @item @code{outputs} (default: @code{"(list (mpd-output))"})
  24261. The audio outputs that MPD can use. By default this is a single output using pulseaudio.
  24262. @end table
  24263. @end deftp
  24264. @deftp {Data Type} mpd-output
  24265. Data type representing an @command{mpd} audio output.
  24266. @table @asis
  24267. @item @code{name} (default: @code{"MPD"})
  24268. The name of the audio output.
  24269. @item @code{type} (default: @code{"pulse"})
  24270. The type of audio output.
  24271. @item @code{enabled?} (default: @code{#t})
  24272. Specifies whether this audio output is enabled when MPD is started. By
  24273. default, all audio outputs are enabled. This is just the default
  24274. setting when there is no state file; with a state file, the previous
  24275. state is restored.
  24276. @item @code{tags?} (default: @code{#t})
  24277. If set to @code{#f}, then MPD will not send tags to this output. This
  24278. is only useful for output plugins that can receive tags, for example the
  24279. @code{httpd} output plugin.
  24280. @item @code{always-on?} (default: @code{#f})
  24281. If set to @code{#t}, then MPD attempts to keep this audio output always
  24282. open. This may be useful for streaming servers, when you don’t want to
  24283. disconnect all listeners even when playback is accidentally stopped.
  24284. @item @code{mixer-type}
  24285. This field accepts a symbol that specifies which mixer should be used
  24286. for this audio output: the @code{hardware} mixer, the @code{software}
  24287. mixer, the @code{null} mixer (allows setting the volume, but with no
  24288. effect; this can be used as a trick to implement an external mixer
  24289. External Mixer) or no mixer (@code{none}).
  24290. @item @code{extra-options} (default: @code{'()})
  24291. An association list of option symbols to string values to be appended to
  24292. the audio output configuration.
  24293. @end table
  24294. @end deftp
  24295. The following example shows a configuration of @code{mpd} that provides
  24296. an HTTP audio streaming output.
  24297. @lisp
  24298. (service mpd-service-type
  24299. (mpd-configuration
  24300. (outputs
  24301. (list (mpd-output
  24302. (name "streaming")
  24303. (type "httpd")
  24304. (mixer-type 'null)
  24305. (extra-options
  24306. `((encoder . "vorbis")
  24307. (port . "8080"))))))))
  24308. @end lisp
  24309. @node Virtualization Services
  24310. @subsection Virtualization Services
  24311. The @code{(gnu services virtualization)} module provides services for
  24312. the libvirt and virtlog daemons, as well as other virtualization-related
  24313. services.
  24314. @subsubheading Libvirt daemon
  24315. @code{libvirtd} is the server side daemon component of the libvirt
  24316. virtualization management system. This daemon runs on host servers
  24317. and performs required management tasks for virtualized guests.
  24318. @deffn {Scheme Variable} libvirt-service-type
  24319. This is the type of the @uref{https://libvirt.org, libvirt daemon}.
  24320. Its value must be a @code{libvirt-configuration}.
  24321. @lisp
  24322. (service libvirt-service-type
  24323. (libvirt-configuration
  24324. (unix-sock-group "libvirt")
  24325. (tls-port "16555")))
  24326. @end lisp
  24327. @end deffn
  24328. @c Auto-generated with (generate-libvirt-documentation)
  24329. Available @code{libvirt-configuration} fields are:
  24330. @deftypevr {@code{libvirt-configuration} parameter} package libvirt
  24331. Libvirt package.
  24332. @end deftypevr
  24333. @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
  24334. Flag listening for secure TLS connections on the public TCP/IP port.
  24335. You must set @code{listen} for this to have any effect.
  24336. It is necessary to setup a CA and issue server certificates before using
  24337. this capability.
  24338. Defaults to @samp{#t}.
  24339. @end deftypevr
  24340. @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
  24341. Listen for unencrypted TCP connections on the public TCP/IP port. You must
  24342. set @code{listen} for this to have any effect.
  24343. Using the TCP socket requires SASL authentication by default. Only SASL
  24344. mechanisms which support data encryption are allowed. This is
  24345. DIGEST_MD5 and GSSAPI (Kerberos5).
  24346. Defaults to @samp{#f}.
  24347. @end deftypevr
  24348. @deftypevr {@code{libvirt-configuration} parameter} string tls-port
  24349. Port for accepting secure TLS connections. This can be a port number,
  24350. or service name.
  24351. Defaults to @samp{"16514"}.
  24352. @end deftypevr
  24353. @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
  24354. Port for accepting insecure TCP connections. This can be a port number,
  24355. or service name.
  24356. Defaults to @samp{"16509"}.
  24357. @end deftypevr
  24358. @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
  24359. IP address or hostname used for client connections.
  24360. Defaults to @samp{"0.0.0.0"}.
  24361. @end deftypevr
  24362. @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
  24363. Flag toggling mDNS advertisement of the libvirt service.
  24364. Alternatively can disable for all services on a host by stopping the
  24365. Avahi daemon.
  24366. Defaults to @samp{#f}.
  24367. @end deftypevr
  24368. @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
  24369. Default mDNS advertisement name. This must be unique on the immediate
  24370. broadcast network.
  24371. Defaults to @samp{"Virtualization Host <hostname>"}.
  24372. @end deftypevr
  24373. @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
  24374. UNIX domain socket group ownership. This can be used to allow a
  24375. 'trusted' set of users access to management capabilities without
  24376. becoming root.
  24377. Defaults to @samp{"root"}.
  24378. @end deftypevr
  24379. @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
  24380. UNIX socket permissions for the R/O socket. This is used for monitoring
  24381. VM status only.
  24382. Defaults to @samp{"0777"}.
  24383. @end deftypevr
  24384. @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
  24385. UNIX socket permissions for the R/W socket. Default allows only root.
  24386. If PolicyKit is enabled on the socket, the default will change to allow
  24387. everyone (eg, 0777)
  24388. Defaults to @samp{"0770"}.
  24389. @end deftypevr
  24390. @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
  24391. UNIX socket permissions for the admin socket. Default allows only owner
  24392. (root), do not change it unless you are sure to whom you are exposing
  24393. the access to.
  24394. Defaults to @samp{"0777"}.
  24395. @end deftypevr
  24396. @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
  24397. The directory in which sockets will be found/created.
  24398. Defaults to @samp{"/var/run/libvirt"}.
  24399. @end deftypevr
  24400. @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
  24401. Authentication scheme for UNIX read-only sockets. By default socket
  24402. permissions allow anyone to connect
  24403. Defaults to @samp{"polkit"}.
  24404. @end deftypevr
  24405. @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
  24406. Authentication scheme for UNIX read-write sockets. By default socket
  24407. permissions only allow root. If PolicyKit support was compiled into
  24408. libvirt, the default will be to use 'polkit' auth.
  24409. Defaults to @samp{"polkit"}.
  24410. @end deftypevr
  24411. @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
  24412. Authentication scheme for TCP sockets. If you don't enable SASL, then
  24413. all TCP traffic is cleartext. Don't do this outside of a dev/test
  24414. scenario.
  24415. Defaults to @samp{"sasl"}.
  24416. @end deftypevr
  24417. @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
  24418. Authentication scheme for TLS sockets. TLS sockets already have
  24419. encryption provided by the TLS layer, and limited authentication is done
  24420. by certificates.
  24421. It is possible to make use of any SASL authentication mechanism as well,
  24422. by using 'sasl' for this option
  24423. Defaults to @samp{"none"}.
  24424. @end deftypevr
  24425. @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
  24426. API access control scheme.
  24427. By default an authenticated user is allowed access to all APIs. Access
  24428. drivers can place restrictions on this.
  24429. Defaults to @samp{()}.
  24430. @end deftypevr
  24431. @deftypevr {@code{libvirt-configuration} parameter} string key-file
  24432. Server key file path. If set to an empty string, then no private key is
  24433. loaded.
  24434. Defaults to @samp{""}.
  24435. @end deftypevr
  24436. @deftypevr {@code{libvirt-configuration} parameter} string cert-file
  24437. Server key file path. If set to an empty string, then no certificate is
  24438. loaded.
  24439. Defaults to @samp{""}.
  24440. @end deftypevr
  24441. @deftypevr {@code{libvirt-configuration} parameter} string ca-file
  24442. Server key file path. If set to an empty string, then no CA certificate
  24443. is loaded.
  24444. Defaults to @samp{""}.
  24445. @end deftypevr
  24446. @deftypevr {@code{libvirt-configuration} parameter} string crl-file
  24447. Certificate revocation list path. If set to an empty string, then no
  24448. CRL is loaded.
  24449. Defaults to @samp{""}.
  24450. @end deftypevr
  24451. @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
  24452. Disable verification of our own server certificates.
  24453. When libvirtd starts it performs some sanity checks against its own
  24454. certificates.
  24455. Defaults to @samp{#f}.
  24456. @end deftypevr
  24457. @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
  24458. Disable verification of client certificates.
  24459. Client certificate verification is the primary authentication mechanism.
  24460. Any client which does not present a certificate signed by the CA will be
  24461. rejected.
  24462. Defaults to @samp{#f}.
  24463. @end deftypevr
  24464. @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
  24465. Whitelist of allowed x509 Distinguished Name.
  24466. Defaults to @samp{()}.
  24467. @end deftypevr
  24468. @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
  24469. Whitelist of allowed SASL usernames. The format for username depends on
  24470. the SASL authentication mechanism.
  24471. Defaults to @samp{()}.
  24472. @end deftypevr
  24473. @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
  24474. Override the compile time default TLS priority string. The default is
  24475. usually @samp{"NORMAL"} unless overridden at build time. Only set this is it
  24476. is desired for libvirt to deviate from the global default settings.
  24477. Defaults to @samp{"NORMAL"}.
  24478. @end deftypevr
  24479. @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
  24480. Maximum number of concurrent client connections to allow over all
  24481. sockets combined.
  24482. Defaults to @samp{5000}.
  24483. @end deftypevr
  24484. @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
  24485. Maximum length of queue of connections waiting to be accepted by the
  24486. daemon. Note, that some protocols supporting retransmission may obey
  24487. this so that a later reattempt at connection succeeds.
  24488. Defaults to @samp{1000}.
  24489. @end deftypevr
  24490. @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
  24491. Maximum length of queue of accepted but not yet authenticated clients.
  24492. Set this to zero to turn this feature off
  24493. Defaults to @samp{20}.
  24494. @end deftypevr
  24495. @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
  24496. Number of workers to start up initially.
  24497. Defaults to @samp{5}.
  24498. @end deftypevr
  24499. @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
  24500. Maximum number of worker threads.
  24501. If the number of active clients exceeds @code{min-workers}, then more
  24502. threads are spawned, up to max_workers limit. Typically you'd want
  24503. max_workers to equal maximum number of clients allowed.
  24504. Defaults to @samp{20}.
  24505. @end deftypevr
  24506. @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
  24507. Number of priority workers. If all workers from above pool are stuck,
  24508. some calls marked as high priority (notably domainDestroy) can be
  24509. executed in this pool.
  24510. Defaults to @samp{5}.
  24511. @end deftypevr
  24512. @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
  24513. Total global limit on concurrent RPC calls.
  24514. Defaults to @samp{20}.
  24515. @end deftypevr
  24516. @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
  24517. Limit on concurrent requests from a single client connection. To avoid
  24518. one client monopolizing the server this should be a small fraction of
  24519. the global max_requests and max_workers parameter.
  24520. Defaults to @samp{5}.
  24521. @end deftypevr
  24522. @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
  24523. Same as @code{min-workers} but for the admin interface.
  24524. Defaults to @samp{1}.
  24525. @end deftypevr
  24526. @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
  24527. Same as @code{max-workers} but for the admin interface.
  24528. Defaults to @samp{5}.
  24529. @end deftypevr
  24530. @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
  24531. Same as @code{max-clients} but for the admin interface.
  24532. Defaults to @samp{5}.
  24533. @end deftypevr
  24534. @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
  24535. Same as @code{max-queued-clients} but for the admin interface.
  24536. Defaults to @samp{5}.
  24537. @end deftypevr
  24538. @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
  24539. Same as @code{max-client-requests} but for the admin interface.
  24540. Defaults to @samp{5}.
  24541. @end deftypevr
  24542. @deftypevr {@code{libvirt-configuration} parameter} integer log-level
  24543. Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
  24544. Defaults to @samp{3}.
  24545. @end deftypevr
  24546. @deftypevr {@code{libvirt-configuration} parameter} string log-filters
  24547. Logging filters.
  24548. A filter allows to select a different logging level for a given category
  24549. of logs. The format for a filter is one of:
  24550. @itemize @bullet
  24551. @item
  24552. x:name
  24553. @item
  24554. x:+name
  24555. @end itemize
  24556. where @code{name} is a string which is matched against the category
  24557. given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
  24558. file, e.g., @samp{"remote"}, @samp{"qemu"}, or @samp{"util.json"} (the
  24559. name in the filter can be a substring of the full category name, in
  24560. order to match multiple similar categories), the optional @samp{"+"}
  24561. prefix tells libvirt to log stack trace for each message matching name,
  24562. and @code{x} is the minimal level where matching messages should be
  24563. logged:
  24564. @itemize @bullet
  24565. @item
  24566. 1: DEBUG
  24567. @item
  24568. 2: INFO
  24569. @item
  24570. 3: WARNING
  24571. @item
  24572. 4: ERROR
  24573. @end itemize
  24574. Multiple filters can be defined in a single filters statement, they just
  24575. need to be separated by spaces.
  24576. Defaults to @samp{"3:remote 4:event"}.
  24577. @end deftypevr
  24578. @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
  24579. Logging outputs.
  24580. An output is one of the places to save logging information. The format
  24581. for an output can be:
  24582. @table @code
  24583. @item x:stderr
  24584. output goes to stderr
  24585. @item x:syslog:name
  24586. use syslog for the output and use the given name as the ident
  24587. @item x:file:file_path
  24588. output to a file, with the given filepath
  24589. @item x:journald
  24590. output to journald logging system
  24591. @end table
  24592. In all case the x prefix is the minimal level, acting as a filter
  24593. @itemize @bullet
  24594. @item
  24595. 1: DEBUG
  24596. @item
  24597. 2: INFO
  24598. @item
  24599. 3: WARNING
  24600. @item
  24601. 4: ERROR
  24602. @end itemize
  24603. Multiple outputs can be defined, they just need to be separated by
  24604. spaces.
  24605. Defaults to @samp{"3:stderr"}.
  24606. @end deftypevr
  24607. @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
  24608. Allows usage of the auditing subsystem to be altered
  24609. @itemize @bullet
  24610. @item
  24611. 0: disable all auditing
  24612. @item
  24613. 1: enable auditing, only if enabled on host
  24614. @item
  24615. 2: enable auditing, and exit if disabled on host.
  24616. @end itemize
  24617. Defaults to @samp{1}.
  24618. @end deftypevr
  24619. @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
  24620. Send audit messages via libvirt logging infrastructure.
  24621. Defaults to @samp{#f}.
  24622. @end deftypevr
  24623. @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
  24624. Host UUID@. UUID must not have all digits be the same.
  24625. Defaults to @samp{""}.
  24626. @end deftypevr
  24627. @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
  24628. Source to read host UUID.
  24629. @itemize @bullet
  24630. @item
  24631. @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
  24632. @item
  24633. @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
  24634. @end itemize
  24635. If @code{dmidecode} does not provide a valid UUID a temporary UUID will
  24636. be generated.
  24637. Defaults to @samp{"smbios"}.
  24638. @end deftypevr
  24639. @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
  24640. A keepalive message is sent to a client after @code{keepalive_interval}
  24641. seconds of inactivity to check if the client is still responding. If
  24642. set to -1, libvirtd will never send keepalive requests; however clients
  24643. can still send them and the daemon will send responses.
  24644. Defaults to @samp{5}.
  24645. @end deftypevr
  24646. @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
  24647. Maximum number of keepalive messages that are allowed to be sent to the
  24648. client without getting any response before the connection is considered
  24649. broken.
  24650. In other words, the connection is automatically closed approximately
  24651. after @code{keepalive_interval * (keepalive_count + 1)} seconds since
  24652. the last message received from the client. When @code{keepalive-count}
  24653. is set to 0, connections will be automatically closed after
  24654. @code{keepalive-interval} seconds of inactivity without sending any
  24655. keepalive messages.
  24656. Defaults to @samp{5}.
  24657. @end deftypevr
  24658. @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
  24659. Same as above but for admin interface.
  24660. Defaults to @samp{5}.
  24661. @end deftypevr
  24662. @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
  24663. Same as above but for admin interface.
  24664. Defaults to @samp{5}.
  24665. @end deftypevr
  24666. @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
  24667. Timeout for Open vSwitch calls.
  24668. The @code{ovs-vsctl} utility is used for the configuration and its
  24669. timeout option is set by default to 5 seconds to avoid potential
  24670. infinite waits blocking libvirt.
  24671. Defaults to @samp{5}.
  24672. @end deftypevr
  24673. @c %end of autogenerated docs
  24674. @subsubheading Virtlog daemon
  24675. The virtlogd service is a server side daemon component of libvirt that is
  24676. used to manage logs from virtual machine consoles.
  24677. This daemon is not used directly by libvirt client applications, rather it
  24678. is called on their behalf by @code{libvirtd}. By maintaining the logs in a
  24679. standalone daemon, the main @code{libvirtd} daemon can be restarted without
  24680. risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
  24681. itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
  24682. @deffn {Scheme Variable} virtlog-service-type
  24683. This is the type of the virtlog daemon.
  24684. Its value must be a @code{virtlog-configuration}.
  24685. @lisp
  24686. (service virtlog-service-type
  24687. (virtlog-configuration
  24688. (max-clients 1000)))
  24689. @end lisp
  24690. @end deffn
  24691. @deftypevar {@code{libvirt} parameter} package libvirt
  24692. Libvirt package.
  24693. @end deftypevar
  24694. @deftypevr {@code{virtlog-configuration} parameter} integer log-level
  24695. Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
  24696. Defaults to @samp{3}.
  24697. @end deftypevr
  24698. @deftypevr {@code{virtlog-configuration} parameter} string log-filters
  24699. Logging filters.
  24700. A filter allows to select a different logging level for a given category
  24701. of logs The format for a filter is one of:
  24702. @itemize @bullet
  24703. @item
  24704. x:name
  24705. @item
  24706. x:+name
  24707. @end itemize
  24708. where @code{name} is a string which is matched against the category
  24709. given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
  24710. file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
  24711. be a substring of the full category name, in order to match multiple
  24712. similar categories), the optional "+" prefix tells libvirt to log stack
  24713. trace for each message matching name, and @code{x} is the minimal level
  24714. where matching messages should be logged:
  24715. @itemize @bullet
  24716. @item
  24717. 1: DEBUG
  24718. @item
  24719. 2: INFO
  24720. @item
  24721. 3: WARNING
  24722. @item
  24723. 4: ERROR
  24724. @end itemize
  24725. Multiple filters can be defined in a single filters statement, they just
  24726. need to be separated by spaces.
  24727. Defaults to @samp{"3:remote 4:event"}.
  24728. @end deftypevr
  24729. @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
  24730. Logging outputs.
  24731. An output is one of the places to save logging information The format
  24732. for an output can be:
  24733. @table @code
  24734. @item x:stderr
  24735. output goes to stderr
  24736. @item x:syslog:name
  24737. use syslog for the output and use the given name as the ident
  24738. @item x:file:file_path
  24739. output to a file, with the given filepath
  24740. @item x:journald
  24741. output to journald logging system
  24742. @end table
  24743. In all case the x prefix is the minimal level, acting as a filter
  24744. @itemize @bullet
  24745. @item
  24746. 1: DEBUG
  24747. @item
  24748. 2: INFO
  24749. @item
  24750. 3: WARNING
  24751. @item
  24752. 4: ERROR
  24753. @end itemize
  24754. Multiple outputs can be defined, they just need to be separated by
  24755. spaces.
  24756. Defaults to @samp{"3:stderr"}.
  24757. @end deftypevr
  24758. @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
  24759. Maximum number of concurrent client connections to allow over all
  24760. sockets combined.
  24761. Defaults to @samp{1024}.
  24762. @end deftypevr
  24763. @deftypevr {@code{virtlog-configuration} parameter} integer max-size
  24764. Maximum file size before rolling over.
  24765. Defaults to @samp{2MB}
  24766. @end deftypevr
  24767. @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
  24768. Maximum number of backup files to keep.
  24769. Defaults to @samp{3}
  24770. @end deftypevr
  24771. @anchor{transparent-emulation-qemu}
  24772. @subsubheading Transparent Emulation with QEMU
  24773. @cindex emulation
  24774. @cindex @code{binfmt_misc}
  24775. @code{qemu-binfmt-service-type} provides support for transparent
  24776. emulation of program binaries built for different architectures---e.g.,
  24777. it allows you to transparently execute an ARMv7 program on an x86_64
  24778. machine. It achieves this by combining the @uref{https://www.qemu.org,
  24779. QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
  24780. This feature only allows you to emulate GNU/Linux on a different
  24781. architecture, but see below for GNU/Hurd support.
  24782. @defvr {Scheme Variable} qemu-binfmt-service-type
  24783. This is the type of the QEMU/binfmt service for transparent emulation.
  24784. Its value must be a @code{qemu-binfmt-configuration} object, which
  24785. specifies the QEMU package to use as well as the architecture we want to
  24786. emulated:
  24787. @lisp
  24788. (service qemu-binfmt-service-type
  24789. (qemu-binfmt-configuration
  24790. (platforms (lookup-qemu-platforms "arm" "aarch64"))))
  24791. @end lisp
  24792. In this example, we enable transparent emulation for the ARM and aarch64
  24793. platforms. Running @code{herd stop qemu-binfmt} turns it off, and
  24794. running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
  24795. herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
  24796. @end defvr
  24797. @deftp {Data Type} qemu-binfmt-configuration
  24798. This is the configuration for the @code{qemu-binfmt} service.
  24799. @table @asis
  24800. @item @code{platforms} (default: @code{'()})
  24801. The list of emulated QEMU platforms. Each item must be a @dfn{platform
  24802. object} as returned by @code{lookup-qemu-platforms} (see below).
  24803. For example, let's suppose you're on an x86_64 machine and you have this
  24804. service:
  24805. @lisp
  24806. (service qemu-binfmt-service-type
  24807. (qemu-binfmt-configuration
  24808. (platforms (lookup-qemu-platforms "arm"))))
  24809. @end lisp
  24810. You can run:
  24811. @example
  24812. guix build -s armhf-linux inkscape
  24813. @end example
  24814. @noindent
  24815. and it will build Inkscape for ARMv7 @emph{as if it were a native
  24816. build}, transparently using QEMU to emulate the ARMv7 CPU@. Pretty handy
  24817. if you'd like to test a package build for an architecture you don't have
  24818. access to!
  24819. @item @code{qemu} (default: @code{qemu})
  24820. The QEMU package to use.
  24821. @end table
  24822. @end deftp
  24823. @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
  24824. Return the list of QEMU platform objects corresponding to
  24825. @var{platforms}@dots{}. @var{platforms} must be a list of strings
  24826. corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
  24827. @code{"mips64el"}, and so on.
  24828. @end deffn
  24829. @deffn {Scheme Procedure} qemu-platform? @var{obj}
  24830. Return true if @var{obj} is a platform object.
  24831. @end deffn
  24832. @deffn {Scheme Procedure} qemu-platform-name @var{platform}
  24833. Return the name of @var{platform}---a string such as @code{"arm"}.
  24834. @end deffn
  24835. @subsubheading QEMU Guest Agent
  24836. @cindex emulation
  24837. The QEMU guest agent provides control over the emulated system to the
  24838. host. The @code{qemu-guest-agent} service runs the agent on Guix
  24839. guests. To control the agent from the host, open a socket by invoking
  24840. QEMU with the following arguments:
  24841. @example
  24842. qemu-system-x86_64 \
  24843. -chardev socket,path=/tmp/qga.sock,server=on,wait=off,id=qga0 \
  24844. -device virtio-serial \
  24845. -device virtserialport,chardev=qga0,name=org.qemu.guest_agent.0 \
  24846. ...
  24847. @end example
  24848. This creates a socket at @file{/tmp/qga.sock} on the host. Once the
  24849. guest agent is running, you can issue commands with @code{socat}:
  24850. @example
  24851. $ guix shell socat -- socat unix-connect:/tmp/qga.sock stdio
  24852. @{"execute": "guest-get-host-name"@}
  24853. @{"return": @{"host-name": "guix"@}@}
  24854. @end example
  24855. See @url{https://wiki.qemu.org/Features/GuestAgent,QEMU guest agent
  24856. documentation} for more options and commands.
  24857. @defvr {Scheme Variable} qemu-guest-agent-service-type
  24858. Service type for the QEMU guest agent service.
  24859. @end defvr
  24860. @deftp {Data Type} qemu-guest-agent-configuration
  24861. Configuration for the @code{qemu-guest-agent} service.
  24862. @table @asis
  24863. @item @code{qemu} (default: @code{qemu-minimal})
  24864. The QEMU package to use.
  24865. @item @code{device} (default: @code{""})
  24866. File name of the device or socket the agent uses to communicate with the
  24867. host. If empty, QEMU uses a default file name.
  24868. @end table
  24869. @end deftp
  24870. @subsubheading The Hurd in a Virtual Machine
  24871. @cindex @code{hurd}
  24872. @cindex the Hurd
  24873. @cindex childhurd
  24874. Service @code{hurd-vm} provides support for running GNU/Hurd in a
  24875. virtual machine (VM), a so-called @dfn{childhurd}. This service is meant
  24876. to be used on GNU/Linux and the given GNU/Hurd operating system
  24877. configuration is cross-compiled. The virtual machine is a Shepherd
  24878. service that can be referred to by the names @code{hurd-vm} and
  24879. @code{childhurd} and be controlled with commands such as:
  24880. @example
  24881. herd start hurd-vm
  24882. herd stop childhurd
  24883. @end example
  24884. When the service is running, you can view its console by connecting to
  24885. it with a VNC client, for example with:
  24886. @example
  24887. guix shell tigervnc-client -- vncviewer localhost:5900
  24888. @end example
  24889. The default configuration (see @code{hurd-vm-configuration} below)
  24890. spawns a secure shell (SSH) server in your GNU/Hurd system, which QEMU
  24891. (the virtual machine emulator) redirects to port 10222 on the host.
  24892. Thus, you can connect over SSH to the childhurd with:
  24893. @example
  24894. ssh root@@localhost -p 10022
  24895. @end example
  24896. The childhurd is volatile and stateless: it starts with a fresh root
  24897. file system every time you restart it. By default though, all the files
  24898. under @file{/etc/childhurd} on the host are copied as is to the root
  24899. file system of the childhurd when it boots. This allows you to
  24900. initialize ``secrets'' inside the VM: SSH host keys, authorized
  24901. substitute keys, and so on---see the explanation of @code{secret-root}
  24902. below.
  24903. @defvr {Scheme Variable} hurd-vm-service-type
  24904. This is the type of the Hurd in a Virtual Machine service. Its value
  24905. must be a @code{hurd-vm-configuration} object, which specifies the
  24906. operating system (@pxref{operating-system Reference}) and the disk size
  24907. for the Hurd Virtual Machine, the QEMU package to use as well as the
  24908. options for running it.
  24909. For example:
  24910. @lisp
  24911. (service hurd-vm-service-type
  24912. (hurd-vm-configuration
  24913. (disk-size (* 5000 (expt 2 20))) ;5G
  24914. (memory-size 1024))) ;1024MiB
  24915. @end lisp
  24916. would create a disk image big enough to build GNU@tie{}Hello, with some
  24917. extra memory.
  24918. @end defvr
  24919. @deftp {Data Type} hurd-vm-configuration
  24920. The data type representing the configuration for
  24921. @code{hurd-vm-service-type}.
  24922. @table @asis
  24923. @item @code{os} (default: @var{%hurd-vm-operating-system})
  24924. The operating system to instantiate. This default is bare-bones with a
  24925. permissive OpenSSH secure shell daemon listening on port 2222
  24926. (@pxref{Networking Services, @code{openssh-service-type}}).
  24927. @item @code{qemu} (default: @code{qemu-minimal})
  24928. The QEMU package to use.
  24929. @item @code{image} (default: @var{hurd-vm-disk-image})
  24930. The procedure used to build the disk-image built from this
  24931. configuration.
  24932. @item @code{disk-size} (default: @code{'guess})
  24933. The size of the disk image.
  24934. @item @code{memory-size} (default: @code{512})
  24935. The memory size of the Virtual Machine in mebibytes.
  24936. @item @code{options} (default: @code{'("--snapshot")})
  24937. The extra options for running QEMU.
  24938. @item @code{id} (default: @code{#f})
  24939. If set, a non-zero positive integer used to parameterize Childhurd
  24940. instances. It is appended to the service's name,
  24941. e.g. @code{childhurd1}.
  24942. @item @code{net-options} (default: @var{hurd-vm-net-options})
  24943. The procedure used to produce the list of QEMU networking options.
  24944. By default, it produces
  24945. @lisp
  24946. '("--device" "rtl8139,netdev=net0"
  24947. "--netdev" (string-append
  24948. "user,id=net0,"
  24949. "hostfwd=tcp:127.0.0.1:@var{secrets-port}-:1004,"
  24950. "hostfwd=tcp:127.0.0.1:@var{ssh-port}-:2222,"
  24951. "hostfwd=tcp:127.0.0.1:@var{vnc-port}-:5900"))
  24952. @end lisp
  24953. with forwarded ports:
  24954. @example
  24955. @var{secrets-port}: @code{(+ 11004 (* 1000 @var{ID}))}
  24956. @var{ssh-port}: @code{(+ 10022 (* 1000 @var{ID}))}
  24957. @var{vnc-port}: @code{(+ 15900 (* 1000 @var{ID}))}
  24958. @end example
  24959. @item @code{secret-root} (default: @file{/etc/childhurd})
  24960. The root directory with out-of-band secrets to be installed into the
  24961. childhurd once it runs. Childhurds are volatile which means that on
  24962. every startup, secrets such as the SSH host keys and Guix signing key
  24963. are recreated.
  24964. If the @file{/etc/childhurd} directory does not exist, the
  24965. @code{secret-service} running in the Childhurd will be sent an empty
  24966. list of secrets.
  24967. By default, the service automatically populates @file{/etc/childhurd}
  24968. with the following non-volatile secrets, unless they already exist:
  24969. @example
  24970. /etc/childhurd/etc/guix/acl
  24971. /etc/childhurd/etc/guix/signing-key.pub
  24972. /etc/childhurd/etc/guix/signing-key.sec
  24973. /etc/childhurd/etc/ssh/ssh_host_ed25519_key
  24974. /etc/childhurd/etc/ssh/ssh_host_ecdsa_key
  24975. /etc/childhurd/etc/ssh/ssh_host_ed25519_key.pub
  24976. /etc/childhurd/etc/ssh/ssh_host_ecdsa_key.pub
  24977. @end example
  24978. These files are automatically sent to the guest Hurd VM when it boots,
  24979. including permissions.
  24980. @cindex childhurd, offloading
  24981. @cindex Hurd, offloading
  24982. Having these files in place means that only a couple of things are
  24983. missing to allow the host to offload @code{i586-gnu} builds to the
  24984. childhurd:
  24985. @enumerate
  24986. @item
  24987. Authorizing the childhurd's key on the host so that the host accepts
  24988. build results coming from the childhurd, which can be done like so:
  24989. @example
  24990. guix archive --authorize < \
  24991. /etc/childhurd/etc/guix/signing-key.pub
  24992. @end example
  24993. @item
  24994. Adding the childhurd to @file{/etc/guix/machines.scm} (@pxref{Daemon
  24995. Offload Setup}).
  24996. @end enumerate
  24997. We're working towards making that happen automatically---get in touch
  24998. with us at @email{guix-devel@@gnu.org} to discuss it!
  24999. @end table
  25000. @end deftp
  25001. Note that by default the VM image is volatile, i.e., once stopped the
  25002. contents are lost. If you want a stateful image instead, override the
  25003. configuration's @code{image} and @code{options} without
  25004. the @code{--snapshot} flag using something along these lines:
  25005. @lisp
  25006. (service hurd-vm-service-type
  25007. (hurd-vm-configuration
  25008. (image (const "/out/of/store/writable/hurd.img"))
  25009. (options '())))
  25010. @end lisp
  25011. @subsubheading Ganeti
  25012. @cindex ganeti
  25013. @quotation Note
  25014. This service is considered experimental. Configuration options may be changed
  25015. in a backwards-incompatible manner, and not all features have been thorougly
  25016. tested. Users of this service are encouraged to share their experience at
  25017. @email{guix-devel@@gnu.org}.
  25018. @end quotation
  25019. Ganeti is a virtual machine management system. It is designed to keep virtual
  25020. machines running on a cluster of servers even in the event of hardware failures,
  25021. and to make maintenance and recovery tasks easy. It consists of multiple
  25022. services which are described later in this section. In addition to the Ganeti
  25023. service, you will need the OpenSSH service (@pxref{Networking Services,
  25024. @code{openssh-service-type}}), and update the @file{/etc/hosts} file
  25025. (@pxref{operating-system Reference, @code{hosts-file}}) with the cluster name
  25026. and address (or use a DNS server).
  25027. All nodes participating in a Ganeti cluster should have the same Ganeti and
  25028. @file{/etc/hosts} configuration. Here is an example configuration for a Ganeti
  25029. cluster node that supports multiple storage backends, and installs the
  25030. @code{debootstrap} and @code{guix} @dfn{OS providers}:
  25031. @lisp
  25032. (use-package-modules virtualization)
  25033. (use-service-modules base ganeti networking ssh)
  25034. (operating-system
  25035. ;; @dots{}
  25036. (host-name "node1")
  25037. (hosts-file (plain-file "hosts" (format #f "
  25038. 127.0.0.1 localhost
  25039. ::1 localhost
  25040. 192.168.1.200 ganeti.example.com
  25041. 192.168.1.201 node1.example.com node1
  25042. 192.168.1.202 node2.example.com node2
  25043. ")))
  25044. ;; Install QEMU so we can use KVM-based instances, and LVM, DRBD and Ceph
  25045. ;; in order to use the "plain", "drbd" and "rbd" storage backends.
  25046. (packages (append (map specification->package
  25047. '("qemu" "lvm2" "drbd-utils" "ceph"
  25048. ;; Add the debootstrap and guix OS providers.
  25049. "ganeti-instance-guix" "ganeti-instance-debootstrap"))
  25050. %base-packages))
  25051. (services
  25052. (append (list (service static-networking-service-type
  25053. (list (static-networking
  25054. (addresses
  25055. (list (network-address
  25056. (device "eth0")
  25057. (value "192.168.1.201/24"))))
  25058. (routes
  25059. (list (network-route
  25060. (destination "default")
  25061. (gateway "192.168.1.254"))))
  25062. (name-servers '("192.168.1.252"
  25063. "192.168.1.253")))))
  25064. ;; Ganeti uses SSH to communicate between nodes.
  25065. (service openssh-service-type
  25066. (openssh-configuration
  25067. (permit-root-login 'prohibit-password)))
  25068. (service ganeti-service-type
  25069. (ganeti-configuration
  25070. ;; This list specifies allowed file system paths
  25071. ;; for storing virtual machine images.
  25072. (file-storage-paths '("/srv/ganeti/file-storage"))
  25073. ;; This variable configures a single "variant" for
  25074. ;; both Debootstrap and Guix that works with KVM.
  25075. (os %default-ganeti-os))))
  25076. %base-services)))
  25077. @end lisp
  25078. Users are advised to read the
  25079. @url{http://docs.ganeti.org/ganeti/master/html/admin.html,Ganeti
  25080. administrators guide} to learn about the various cluster options and
  25081. day-to-day operations. There is also a
  25082. @url{https://guix.gnu.org/blog/2020/running-a-ganeti-cluster-on-guix/,blog post}
  25083. describing how to configure and initialize a small cluster.
  25084. @defvr {Scheme Variable} ganeti-service-type
  25085. This is a service type that includes all the various services that Ganeti
  25086. nodes should run.
  25087. Its value is a @code{ganeti-configuration} object that defines the package
  25088. to use for CLI operations, as well as configuration for the various daemons.
  25089. Allowed file storage paths and available guest operating systems are also
  25090. configured through this data type.
  25091. @end defvr
  25092. @deftp {Data Type} ganeti-configuration
  25093. The @code{ganeti} service takes the following configuration options:
  25094. @table @asis
  25095. @item @code{ganeti} (default: @code{ganeti})
  25096. The @code{ganeti} package to use. It will be installed to the system profile
  25097. and make @command{gnt-cluster}, @command{gnt-instance}, etc available. Note
  25098. that the value specified here does not affect the other services as each refer
  25099. to a specific @code{ganeti} package (see below).
  25100. @item @code{noded-configuration} (default: @code{(ganeti-noded-configuration)})
  25101. @itemx @code{confd-configuration} (default: @code{(ganeti-confd-configuration)})
  25102. @itemx @code{wconfd-configuration} (default: @code{(ganeti-wconfd-configuration)})
  25103. @itemx @code{luxid-configuration} (default: @code{(ganeti-luxid-configuration)})
  25104. @itemx @code{rapi-configuration} (default: @code{(ganeti-rapi-configuration)})
  25105. @itemx @code{kvmd-configuration} (default: @code{(ganeti-kvmd-configuration)})
  25106. @itemx @code{mond-configuration} (default: @code{(ganeti-mond-configuration)})
  25107. @itemx @code{metad-configuration} (default: @code{(ganeti-metad-configuration)})
  25108. @itemx @code{watcher-configuration} (default: @code{(ganeti-watcher-configuration)})
  25109. @itemx @code{cleaner-configuration} (default: @code{(ganeti-cleaner-configuration)})
  25110. These options control the various daemons and cron jobs that are distributed
  25111. with Ganeti. The possible values for these are described in detail below.
  25112. To override a setting, you must use the configuration type for that service:
  25113. @lisp
  25114. (service ganeti-service-type
  25115. (ganeti-configuration
  25116. (rapi-configuration
  25117. (ganeti-rapi-configuration
  25118. (interface "eth1"))))
  25119. (watcher-configuration
  25120. (ganeti-watcher-configuration
  25121. (rapi-ip "10.0.0.1"))))
  25122. @end lisp
  25123. @item @code{file-storage-paths} (default: @code{'()})
  25124. List of allowed directories for file storage backend.
  25125. @item @code{os} (default: @code{%default-ganeti-os})
  25126. List of @code{<ganeti-os>} records.
  25127. @end table
  25128. In essence @code{ganeti-service-type} is shorthand for declaring each service
  25129. individually:
  25130. @lisp
  25131. (service ganeti-noded-service-type)
  25132. (service ganeti-confd-service-type)
  25133. (service ganeti-wconfd-service-type)
  25134. (service ganeti-luxid-service-type)
  25135. (service ganeti-kvmd-service-type)
  25136. (service ganeti-mond-service-type)
  25137. (service ganeti-metad-service-type)
  25138. (service ganeti-watcher-service-type)
  25139. (service ganeti-cleaner-service-type)
  25140. @end lisp
  25141. Plus a service extension for @code{etc-service-type} that configures the file
  25142. storage backend and OS variants.
  25143. @end deftp
  25144. @deftp {Data Type} ganeti-os
  25145. This data type is suitable for passing to the @code{os} parameter of
  25146. @code{ganeti-configuration}. It takes the following parameters:
  25147. @table @asis
  25148. @item @code{name}
  25149. The name for this OS provider. It is only used to specify where the
  25150. configuration ends up. Setting it to ``debootstrap'' will create
  25151. @file{/etc/ganeti/instance-debootstrap}.
  25152. @item @code{extension}
  25153. The file extension for variants of this OS type. For example
  25154. @file{.conf} or @file{.scm}.
  25155. @item @code{variants} (default: @code{'()})
  25156. List of @code{ganeti-os-variant} objects for this OS.
  25157. @end table
  25158. @end deftp
  25159. @deftp {Data Type} ganeti-os-variant
  25160. This is the data type for a Ganeti OS variant. It takes the following
  25161. parameters:
  25162. @table @asis
  25163. @item @code{name}
  25164. The name of this variant.
  25165. @item @code{configuration}
  25166. A configuration file for this variant.
  25167. @end table
  25168. @end deftp
  25169. @defvr {Scheme Variable} %default-debootstrap-hooks
  25170. This variable contains hooks to configure networking and the GRUB bootloader.
  25171. @end defvr
  25172. @defvr {Scheme Variable} %default-debootstrap-extra-pkgs
  25173. This variable contains a list of packages suitable for a fully-virtualized guest.
  25174. @end defvr
  25175. @deftp {Data Type} debootstrap-configuration
  25176. This data type creates configuration files suitable for the debootstrap OS provider.
  25177. @table @asis
  25178. @item @code{hooks} (default: @code{%default-debootstrap-hooks})
  25179. When not @code{#f}, this must be a G-expression that specifies a directory with
  25180. scripts that will run when the OS is installed. It can also be a list of
  25181. @code{(name . file-like)} pairs. For example:
  25182. @lisp
  25183. `((99-hello-world . ,(plain-file "#!/bin/sh\necho Hello, World")))
  25184. @end lisp
  25185. That will create a directory with one executable named @code{99-hello-world}
  25186. and run it every time this variant is installed. If set to @code{#f}, hooks
  25187. in @file{/etc/ganeti/instance-debootstrap/hooks} will be used, if any.
  25188. @item @code{proxy} (default: @code{#f})
  25189. Optional HTTP proxy to use.
  25190. @item @code{mirror} (default: @code{#f})
  25191. The Debian mirror. Typically something like @code{http://ftp.no.debian.org/debian}.
  25192. The default varies depending on the distribution.
  25193. @item @code{arch} (default: @code{#f})
  25194. The dpkg architecture. Set to @code{armhf} to debootstrap an ARMv7 instance
  25195. on an AArch64 host. Default is to use the current system architecture.
  25196. @item @code{suite} (default: @code{"stable"})
  25197. When set, this must be a Debian distribution ``suite'' such as @code{buster}
  25198. or @code{focal}. If set to @code{#f}, the default for the OS provider is used.
  25199. @item @code{extra-pkgs} (default: @code{%default-debootstrap-extra-pkgs})
  25200. List of extra packages that will get installed by dpkg in addition
  25201. to the minimal system.
  25202. @item @code{components} (default: @code{#f})
  25203. When set, must be a list of Debian repository ``components''. For example
  25204. @code{'("main" "contrib")}.
  25205. @item @code{generate-cache?} (default: @code{#t})
  25206. Whether to automatically cache the generated debootstrap archive.
  25207. @item @code{clean-cache} (default: @code{14})
  25208. Discard the cache after this amount of days. Use @code{#f} to never
  25209. clear the cache.
  25210. @item @code{partition-style} (default: @code{'msdos})
  25211. The type of partition to create. When set, it must be one of
  25212. @code{'msdos}, @code{'none} or a string.
  25213. @item @code{partition-alignment} (default: @code{2048})
  25214. Alignment of the partition in sectors.
  25215. @end table
  25216. @end deftp
  25217. @deffn {Scheme Procedure} debootstrap-variant @var{name} @var{configuration}
  25218. This is a helper procedure that creates a @code{ganeti-os-variant} record. It
  25219. takes two parameters: a name and a @code{debootstrap-configuration} object.
  25220. @end deffn
  25221. @deffn {Scheme Procedure} debootstrap-os @var{variants}@dots{}
  25222. This is a helper procedure that creates a @code{ganeti-os} record. It takes
  25223. a list of variants created with @code{debootstrap-variant}.
  25224. @end deffn
  25225. @deffn {Scheme Procedure} guix-variant @var{name} @var{configuration}
  25226. This is a helper procedure that creates a @code{ganeti-os-variant} record for
  25227. use with the Guix OS provider. It takes a name and a G-expression that returns
  25228. a ``file-like'' (@pxref{G-Expressions, file-like objects}) object containing a
  25229. Guix System configuration.
  25230. @end deffn
  25231. @deffn {Scheme Procedure} guix-os @var{variants}@dots{}
  25232. This is a helper procedure that creates a @code{ganeti-os} record. It
  25233. takes a list of variants produced by @code{guix-variant}.
  25234. @end deffn
  25235. @defvr {Scheme Variable} %default-debootstrap-variants
  25236. This is a convenience variable to make the debootstrap provider work
  25237. ``out of the box'' without users having to declare variants manually. It
  25238. contains a single debootstrap variant with the default configuration:
  25239. @lisp
  25240. (list (debootstrap-variant
  25241. "default"
  25242. (debootstrap-configuration)))
  25243. @end lisp
  25244. @end defvr
  25245. @defvr {Scheme Variable} %default-guix-variants
  25246. This is a convenience variable to make the Guix OS provider work without
  25247. additional configuration. It creates a virtual machine that has an SSH
  25248. server, a serial console, and authorizes the Ganeti hosts SSH keys.
  25249. @lisp
  25250. (list (guix-variant
  25251. "default"
  25252. (file-append ganeti-instance-guix
  25253. "/share/doc/ganeti-instance-guix/examples/dynamic.scm")))
  25254. @end lisp
  25255. @end defvr
  25256. Users can implement support for OS providers unbeknownst to Guix by extending
  25257. the @code{ganeti-os} and @code{ganeti-os-variant} records appropriately.
  25258. For example:
  25259. @lisp
  25260. (ganeti-os
  25261. (name "custom")
  25262. (extension ".conf")
  25263. (variants
  25264. (list (ganeti-os-variant
  25265. (name "foo")
  25266. (configuration (plain-file "bar" "this is fine"))))))
  25267. @end lisp
  25268. That creates @file{/etc/ganeti/instance-custom/variants/foo.conf} which points
  25269. to a file in the store with contents @code{this is fine}. It also creates
  25270. @file{/etc/ganeti/instance-custom/variants/variants.list} with contents @code{foo}.
  25271. Obviously this may not work for all OS providers out there. If you find the
  25272. interface limiting, please reach out to @email{guix-devel@@gnu.org}.
  25273. The rest of this section documents the various services that are included by
  25274. @code{ganeti-service-type}.
  25275. @defvr {Scheme Variable} ganeti-noded-service-type
  25276. @command{ganeti-noded} is the daemon responsible for node-specific functions
  25277. within the Ganeti system. The value of this service must be a
  25278. @code{ganeti-noded-configuration} object.
  25279. @end defvr
  25280. @deftp {Data Type} ganeti-noded-configuration
  25281. This is the configuration for the @code{ganeti-noded} service.
  25282. @table @asis
  25283. @item @code{ganeti} (default: @code{ganeti})
  25284. The @code{ganeti} package to use for this service.
  25285. @item @code{port} (default: @code{1811})
  25286. The TCP port on which the node daemon listens for network requests.
  25287. @item @code{address} (default: @code{"0.0.0.0"})
  25288. The network address that the daemon will bind to. The default address means
  25289. bind to all available addresses.
  25290. @item @code{interface} (default: @code{#f})
  25291. When this is set, it must be a specific network interface (e.g.@: @code{eth0})
  25292. that the daemon will bind to.
  25293. @item @code{max-clients} (default: @code{20})
  25294. This sets a limit on the maximum number of simultaneous client connections
  25295. that the daemon will handle. Connections above this count are accepted, but
  25296. no responses will be sent until enough connections have closed.
  25297. @item @code{ssl?} (default: @code{#t})
  25298. Whether to use SSL/TLS to encrypt network communications. The certificate
  25299. is automatically provisioned by the cluster and can be rotated with
  25300. @command{gnt-cluster renew-crypto}.
  25301. @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
  25302. This can be used to provide a specific encryption key for TLS communications.
  25303. @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
  25304. This can be used to provide a specific certificate for TLS communications.
  25305. @item @code{debug?} (default: @code{#f})
  25306. When true, the daemon performs additional logging for debugging purposes.
  25307. Note that this will leak encryption details to the log files, use with caution.
  25308. @end table
  25309. @end deftp
  25310. @defvr {Scheme Variable} ganeti-confd-service-type
  25311. @command{ganeti-confd} answers queries related to the configuration of a
  25312. Ganeti cluster. The purpose of this daemon is to have a highly available
  25313. and fast way to query cluster configuration values. It is automatically
  25314. active on all @dfn{master candidates}. The value of this service must be a
  25315. @code{ganeti-confd-configuration} object.
  25316. @end defvr
  25317. @deftp {Data Type} ganeti-confd-configuration
  25318. This is the configuration for the @code{ganeti-confd} service.
  25319. @table @asis
  25320. @item @code{ganeti} (default: @code{ganeti})
  25321. The @code{ganeti} package to use for this service.
  25322. @item @code{port} (default: @code{1814})
  25323. The UDP port on which to listen for network requests.
  25324. @item @code{address} (default: @code{"0.0.0.0"})
  25325. Network address that the daemon will bind to.
  25326. @item @code{debug?} (default: @code{#f})
  25327. When true, the daemon performs additional logging for debugging purposes.
  25328. @end table
  25329. @end deftp
  25330. @defvr {Scheme Variable} ganeti-wconfd-service-type
  25331. @command{ganeti-wconfd} is the daemon that has authoritative knowledge
  25332. about the cluster configuration and is the only entity that can accept
  25333. changes to it. All jobs that need to modify the configuration will do so
  25334. by sending appropriate requests to this daemon. It only runs on the
  25335. @dfn{master node} and will automatically disable itself on other nodes.
  25336. The value of this service must be a
  25337. @code{ganeti-wconfd-configuration} object.
  25338. @end defvr
  25339. @deftp {Data Type} ganeti-wconfd-configuration
  25340. This is the configuration for the @code{ganeti-wconfd} service.
  25341. @table @asis
  25342. @item @code{ganeti} (default: @code{ganeti})
  25343. The @code{ganeti} package to use for this service.
  25344. @item @code{no-voting?} (default: @code{#f})
  25345. The daemon will refuse to start if the majority of cluster nodes does not
  25346. agree that it is running on the master node. Set to @code{#t} to start
  25347. even if a quorum can not be reached (dangerous, use with caution).
  25348. @item @code{debug?} (default: @code{#f})
  25349. When true, the daemon performs additional logging for debugging purposes.
  25350. @end table
  25351. @end deftp
  25352. @defvr {Scheme Variable} ganeti-luxid-service-type
  25353. @command{ganeti-luxid} is a daemon used to answer queries related to the
  25354. configuration and the current live state of a Ganeti cluster. Additionally,
  25355. it is the authoritative daemon for the Ganeti job queue. Jobs can be
  25356. submitted via this daemon and it schedules and starts them.
  25357. It takes a @code{ganeti-luxid-configuration} object.
  25358. @end defvr
  25359. @deftp {Data Type} ganeti-luxid-configuration
  25360. This is the configuration for the @code{ganeti-luxid} service.
  25361. @table @asis
  25362. @item @code{ganeti} (default: @code{ganeti})
  25363. The @code{ganeti} package to use for this service.
  25364. @item @code{no-voting?} (default: @code{#f})
  25365. The daemon will refuse to start if it cannot verify that the majority of
  25366. cluster nodes believes that it is running on the master node. Set to
  25367. @code{#t} to ignore such checks and start anyway (this can be dangerous).
  25368. @item @code{debug?} (default: @code{#f})
  25369. When true, the daemon performs additional logging for debugging purposes.
  25370. @end table
  25371. @end deftp
  25372. @defvr {Scheme Variable} ganeti-rapi-service-type
  25373. @command{ganeti-rapi} provides a remote API for Ganeti clusters. It runs on
  25374. the master node and can be used to perform cluster actions programmatically
  25375. via a JSON-based RPC protocol.
  25376. Most query operations are allowed without authentication (unless
  25377. @var{require-authentication?} is set), whereas write operations require
  25378. explicit authorization via the @file{/var/lib/ganeti/rapi/users} file. See
  25379. the @url{http://docs.ganeti.org/ganeti/master/html/rapi.html, Ganeti Remote
  25380. API documentation} for more information.
  25381. The value of this service must be a @code{ganeti-rapi-configuration} object.
  25382. @end defvr
  25383. @deftp {Data Type} ganeti-rapi-configuration
  25384. This is the configuration for the @code{ganeti-rapi} service.
  25385. @table @asis
  25386. @item @code{ganeti} (default: @code{ganeti})
  25387. The @code{ganeti} package to use for this service.
  25388. @item @code{require-authentication?} (default: @code{#f})
  25389. Whether to require authentication even for read-only operations.
  25390. @item @code{port} (default: @code{5080})
  25391. The TCP port on which to listen to API requests.
  25392. @item @code{address} (default: @code{"0.0.0.0"})
  25393. The network address that the service will bind to. By default it listens
  25394. on all configured addresses.
  25395. @item @code{interface} (default: @code{#f})
  25396. When set, it must specify a specific network interface such as @code{eth0}
  25397. that the daemon will bind to.
  25398. @item @code{max-clients} (default: @code{20})
  25399. The maximum number of simultaneous client requests to handle. Further
  25400. connections are allowed, but no responses are sent until enough connections
  25401. have closed.
  25402. @item @code{ssl?} (default: @code{#t})
  25403. Whether to use SSL/TLS encryption on the RAPI port.
  25404. @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
  25405. This can be used to provide a specific encryption key for TLS communications.
  25406. @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
  25407. This can be used to provide a specific certificate for TLS communications.
  25408. @item @code{debug?} (default: @code{#f})
  25409. When true, the daemon performs additional logging for debugging purposes.
  25410. Note that this will leak encryption details to the log files, use with caution.
  25411. @end table
  25412. @end deftp
  25413. @defvr {Scheme Variable} ganeti-kvmd-service-type
  25414. @command{ganeti-kvmd} is responsible for determining whether a given KVM
  25415. instance was shut down by an administrator or a user. Normally Ganeti will
  25416. restart an instance that was not stopped through Ganeti itself. If the
  25417. cluster option @code{user_shutdown} is true, this daemon monitors the
  25418. @code{QMP} socket provided by QEMU and listens for shutdown events, and
  25419. marks the instance as @dfn{USER_down} instead of @dfn{ERROR_down} when
  25420. it shuts down gracefully by itself.
  25421. It takes a @code{ganeti-kvmd-configuration} object.
  25422. @end defvr
  25423. @deftp {Data Type} ganeti-kvmd-configuration
  25424. @table @asis
  25425. @item @code{ganeti} (default: @code{ganeti})
  25426. The @code{ganeti} package to use for this service.
  25427. @item @code{debug?} (default: @code{#f})
  25428. When true, the daemon performs additional logging for debugging purposes.
  25429. @end table
  25430. @end deftp
  25431. @defvr {Scheme Variable} ganeti-mond-service-type
  25432. @command{ganeti-mond} is an optional daemon that provides Ganeti monitoring
  25433. functionality. It is responsible for running data collectors and publish the
  25434. collected information through a HTTP interface.
  25435. It takes a @code{ganeti-mond-configuration} object.
  25436. @end defvr
  25437. @deftp {Data Type} ganeti-mond-configuration
  25438. @table @asis
  25439. @item @code{ganeti} (default: @code{ganeti})
  25440. The @code{ganeti} package to use for this service.
  25441. @item @code{port} (default: @code{1815})
  25442. The port on which the daemon will listen.
  25443. @item @code{address} (default: @code{"0.0.0.0"})
  25444. The network address that the daemon will bind to. By default it binds to all
  25445. available interfaces.
  25446. @item @code{debug?} (default: @code{#f})
  25447. When true, the daemon performs additional logging for debugging purposes.
  25448. @end table
  25449. @end deftp
  25450. @defvr {Scheme Variable} ganeti-metad-service-type
  25451. @command{ganeti-metad} is an optional daemon that can be used to provide
  25452. information about the cluster to instances or OS install scripts.
  25453. It takes a @code{ganeti-metad-configuration} object.
  25454. @end defvr
  25455. @deftp {Data Type} ganeti-metad-configuration
  25456. @table @asis
  25457. @item @code{ganeti} (default: @code{ganeti})
  25458. The @code{ganeti} package to use for this service.
  25459. @item @code{port} (default: @code{80})
  25460. The port on which the daemon will listen.
  25461. @item @code{address} (default: @code{#f})
  25462. If set, the daemon will bind to this address only. If left unset, the behavior
  25463. depends on the cluster configuration.
  25464. @item @code{debug?} (default: @code{#f})
  25465. When true, the daemon performs additional logging for debugging purposes.
  25466. @end table
  25467. @end deftp
  25468. @defvr {Scheme Variable} ganeti-watcher-service-type
  25469. @command{ganeti-watcher} is a script designed to run periodically and ensure
  25470. the health of a cluster. It will automatically restart instances that have
  25471. stopped without Ganeti's consent, and repairs DRBD links in case a node has
  25472. rebooted. It also archives old cluster jobs and restarts Ganeti daemons
  25473. that are not running. If the cluster parameter @code{ensure_node_health}
  25474. is set, the watcher will also shutdown instances and DRBD devices if the
  25475. node it is running on is declared offline by known master candidates.
  25476. It can be paused on all nodes with @command{gnt-cluster watcher pause}.
  25477. The service takes a @code{ganeti-watcher-configuration} object.
  25478. @end defvr
  25479. @deftp {Data Type} ganeti-watcher-configuration
  25480. @table @asis
  25481. @item @code{ganeti} (default: @code{ganeti})
  25482. The @code{ganeti} package to use for this service.
  25483. @item @code{schedule} (default: @code{'(next-second-from (next-minute (range 0 60 5)))})
  25484. How often to run the script. The default is every five minutes.
  25485. @item @code{rapi-ip} (default: @code{#f})
  25486. This option needs to be specified only if the RAPI daemon is configured to use
  25487. a particular interface or address. By default the cluster address is used.
  25488. @item @code{job-age} (default: @code{(* 6 3600)})
  25489. Archive cluster jobs older than this age, specified in seconds. The default
  25490. is 6 hours. This keeps @command{gnt-job list} manageable.
  25491. @item @code{verify-disks?} (default: @code{#t})
  25492. If this is @code{#f}, the watcher will not try to repair broken DRBD links
  25493. automatically. Administrators will need to use @command{gnt-cluster verify-disks}
  25494. manually instead.
  25495. @item @code{debug?} (default: @code{#f})
  25496. When @code{#t}, the script performs additional logging for debugging purposes.
  25497. @end table
  25498. @end deftp
  25499. @defvr {Scheme Variable} ganeti-cleaner-service-type
  25500. @command{ganeti-cleaner} is a script designed to run periodically and remove
  25501. old files from the cluster. This service type controls two @dfn{cron jobs}:
  25502. one intended for the master node that permanently purges old cluster jobs,
  25503. and one intended for every node that removes expired X509 certificates, keys,
  25504. and outdated @command{ganeti-watcher} information. Like all Ganeti services,
  25505. it is safe to include even on non-master nodes as it will disable itself as
  25506. necessary.
  25507. It takes a @code{ganeti-cleaner-configuration} object.
  25508. @end defvr
  25509. @deftp {Data Type} ganeti-cleaner-configuration
  25510. @table @asis
  25511. @item @code{ganeti} (default: @code{ganeti})
  25512. The @code{ganeti} package to use for the @command{gnt-cleaner} command.
  25513. @item @code{master-schedule} (default: @code{"45 1 * * *"})
  25514. How often to run the master cleaning job. The default is once per day, at
  25515. 01:45:00.
  25516. @item @code{node-schedule} (default: @code{"45 2 * * *"})
  25517. How often to run the node cleaning job. The default is once per day, at
  25518. 02:45:00.
  25519. @end table
  25520. @end deftp
  25521. @node Version Control Services
  25522. @subsection Version Control Services
  25523. The @code{(gnu services version-control)} module provides a service to
  25524. allow remote access to local Git repositories. There are three options:
  25525. the @code{git-daemon-service}, which provides access to repositories via
  25526. the @code{git://} unsecured TCP-based protocol, extending the
  25527. @code{nginx} web server to proxy some requests to
  25528. @code{git-http-backend}, or providing a web interface with
  25529. @code{cgit-service-type}.
  25530. @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
  25531. Return a service that runs @command{git daemon}, a simple TCP server to
  25532. expose repositories over the Git protocol for anonymous access.
  25533. The optional @var{config} argument should be a
  25534. @code{<git-daemon-configuration>} object, by default it allows read-only
  25535. access to exported@footnote{By creating the magic file
  25536. @file{git-daemon-export-ok} in the repository directory.} repositories under
  25537. @file{/srv/git}.
  25538. @end deffn
  25539. @deftp {Data Type} git-daemon-configuration
  25540. Data type representing the configuration for @code{git-daemon-service}.
  25541. @table @asis
  25542. @item @code{package} (default: @code{git})
  25543. Package object of the Git distributed version control system.
  25544. @item @code{export-all?} (default: @code{#f})
  25545. Whether to allow access for all Git repositories, even if they do not
  25546. have the @file{git-daemon-export-ok} file.
  25547. @item @code{base-path} (default: @file{/srv/git})
  25548. Whether to remap all the path requests as relative to the given path.
  25549. If you run @command{git daemon} with @code{(base-path "/srv/git")} on
  25550. @samp{example.com}, then if you later try to pull
  25551. @indicateurl{git://example.com/hello.git}, git daemon will interpret the
  25552. path as @file{/srv/git/hello.git}.
  25553. @item @code{user-path} (default: @code{#f})
  25554. Whether to allow @code{~user} notation to be used in requests. When
  25555. specified with empty string, requests to
  25556. @indicateurl{git://host/~alice/foo} is taken as a request to access
  25557. @code{foo} repository in the home directory of user @code{alice}. If
  25558. @code{(user-path "@var{path}")} is specified, the same request is taken
  25559. as a request to access @file{@var{path}/foo} repository in the home
  25560. directory of user @code{alice}.
  25561. @item @code{listen} (default: @code{'()})
  25562. Whether to listen on specific IP addresses or hostnames, defaults to
  25563. all.
  25564. @item @code{port} (default: @code{#f})
  25565. Whether to listen on an alternative port, which defaults to 9418.
  25566. @item @code{whitelist} (default: @code{'()})
  25567. If not empty, only allow access to this list of directories.
  25568. @item @code{extra-options} (default: @code{'()})
  25569. Extra options will be passed to @command{git daemon}, please run
  25570. @command{man git-daemon} for more information.
  25571. @end table
  25572. @end deftp
  25573. The @code{git://} protocol lacks authentication. When you pull from a
  25574. repository fetched via @code{git://}, you don't know whether the data you
  25575. receive was modified or is even coming from the specified host, and your
  25576. connection is subject to eavesdropping. It's better to use an authenticated
  25577. and encrypted transport, such as @code{https}. Although Git allows you
  25578. to serve repositories using unsophisticated file-based web servers,
  25579. there is a faster protocol implemented by the @code{git-http-backend}
  25580. program. This program is the back-end of a proper Git web service. It
  25581. is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
  25582. on running the necessary @code{fcgiwrap} daemon.
  25583. Guix has a separate configuration data type for serving Git repositories
  25584. over HTTP.
  25585. @deftp {Data Type} git-http-configuration
  25586. Data type representing the configuration for a future
  25587. @code{git-http-service-type}; can currently be used to configure Nginx
  25588. through @code{git-http-nginx-location-configuration}.
  25589. @table @asis
  25590. @item @code{package} (default: @var{git})
  25591. Package object of the Git distributed version control system.
  25592. @item @code{git-root} (default: @file{/srv/git})
  25593. Directory containing the Git repositories to expose to the world.
  25594. @item @code{export-all?} (default: @code{#f})
  25595. Whether to expose access for all Git repositories in @var{git-root},
  25596. even if they do not have the @file{git-daemon-export-ok} file.
  25597. @item @code{uri-path} (default: @samp{/git/})
  25598. Path prefix for Git access. With the default @samp{/git/} prefix, this
  25599. will map @indicateurl{http://@var{server}/git/@var{repo}.git} to
  25600. @file{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
  25601. with this prefix are not passed on to this Git instance.
  25602. @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
  25603. The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
  25604. Services}.
  25605. @end table
  25606. @end deftp
  25607. There is no @code{git-http-service-type}, currently; instead you can
  25608. create an @code{nginx-location-configuration} from a
  25609. @code{git-http-configuration} and then add that location to a web
  25610. server.
  25611. @deffn {Scheme Procedure} git-http-nginx-location-configuration @
  25612. [config=(git-http-configuration)]
  25613. Compute an @code{nginx-location-configuration} that corresponds to the
  25614. given Git http configuration. An example nginx service definition to
  25615. serve the default @file{/srv/git} over HTTPS might be:
  25616. @lisp
  25617. (service nginx-service-type
  25618. (nginx-configuration
  25619. (server-blocks
  25620. (list
  25621. (nginx-server-configuration
  25622. (listen '("443 ssl"))
  25623. (server-name "git.my-host.org")
  25624. (ssl-certificate
  25625. "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
  25626. (ssl-certificate-key
  25627. "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
  25628. (locations
  25629. (list
  25630. (git-http-nginx-location-configuration
  25631. (git-http-configuration (uri-path "/"))))))))))
  25632. @end lisp
  25633. This example assumes that you are using Let's Encrypt to get your TLS
  25634. certificate. @xref{Certificate Services}. The default @code{certbot}
  25635. service will redirect all HTTP traffic on @code{git.my-host.org} to
  25636. HTTPS@. You will also need to add an @code{fcgiwrap} proxy to your
  25637. system services. @xref{Web Services}.
  25638. @end deffn
  25639. @subsubheading Cgit Service
  25640. @cindex Cgit service
  25641. @cindex Git, web interface
  25642. @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
  25643. repositories written in C.
  25644. The following example will configure the service with default values.
  25645. By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
  25646. @lisp
  25647. (service cgit-service-type)
  25648. @end lisp
  25649. The @code{file-object} type designates either a file-like object
  25650. (@pxref{G-Expressions, file-like objects}) or a string.
  25651. @c %start of fragment
  25652. Available @code{cgit-configuration} fields are:
  25653. @deftypevr {@code{cgit-configuration} parameter} package package
  25654. The CGIT package.
  25655. @end deftypevr
  25656. @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
  25657. NGINX configuration.
  25658. @end deftypevr
  25659. @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
  25660. Specifies a command which will be invoked to format the content of about
  25661. pages (both top-level and for each repository).
  25662. Defaults to @samp{""}.
  25663. @end deftypevr
  25664. @deftypevr {@code{cgit-configuration} parameter} string agefile
  25665. Specifies a path, relative to each repository path, which can be used to
  25666. specify the date and time of the youngest commit in the repository.
  25667. Defaults to @samp{""}.
  25668. @end deftypevr
  25669. @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
  25670. Specifies a command that will be invoked for authenticating repository
  25671. access.
  25672. Defaults to @samp{""}.
  25673. @end deftypevr
  25674. @deftypevr {@code{cgit-configuration} parameter} string branch-sort
  25675. Flag which, when set to @samp{age}, enables date ordering in the branch
  25676. ref list, and when set @samp{name} enables ordering by branch name.
  25677. Defaults to @samp{"name"}.
  25678. @end deftypevr
  25679. @deftypevr {@code{cgit-configuration} parameter} string cache-root
  25680. Path used to store the cgit cache entries.
  25681. Defaults to @samp{"/var/cache/cgit"}.
  25682. @end deftypevr
  25683. @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
  25684. Number which specifies the time-to-live, in minutes, for the cached
  25685. version of repository pages accessed with a fixed SHA1.
  25686. Defaults to @samp{-1}.
  25687. @end deftypevr
  25688. @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
  25689. Number which specifies the time-to-live, in minutes, for the cached
  25690. version of repository pages accessed without a fixed SHA1.
  25691. Defaults to @samp{5}.
  25692. @end deftypevr
  25693. @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
  25694. Number which specifies the time-to-live, in minutes, for the cached
  25695. version of the repository summary page.
  25696. Defaults to @samp{5}.
  25697. @end deftypevr
  25698. @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
  25699. Number which specifies the time-to-live, in minutes, for the cached
  25700. version of the repository index page.
  25701. Defaults to @samp{5}.
  25702. @end deftypevr
  25703. @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
  25704. Number which specifies the time-to-live, in minutes, for the result of
  25705. scanning a path for Git repositories.
  25706. Defaults to @samp{15}.
  25707. @end deftypevr
  25708. @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
  25709. Number which specifies the time-to-live, in minutes, for the cached
  25710. version of the repository about page.
  25711. Defaults to @samp{15}.
  25712. @end deftypevr
  25713. @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
  25714. Number which specifies the time-to-live, in minutes, for the cached
  25715. version of snapshots.
  25716. Defaults to @samp{5}.
  25717. @end deftypevr
  25718. @deftypevr {@code{cgit-configuration} parameter} integer cache-size
  25719. The maximum number of entries in the cgit cache. When set to @samp{0},
  25720. caching is disabled.
  25721. Defaults to @samp{0}.
  25722. @end deftypevr
  25723. @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
  25724. Sort items in the repo list case sensitively.
  25725. Defaults to @samp{#t}.
  25726. @end deftypevr
  25727. @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
  25728. List of common prefixes which, when combined with a repository URL,
  25729. generates valid clone URLs for the repository.
  25730. Defaults to @samp{()}.
  25731. @end deftypevr
  25732. @deftypevr {@code{cgit-configuration} parameter} list clone-url
  25733. List of @code{clone-url} templates.
  25734. Defaults to @samp{()}.
  25735. @end deftypevr
  25736. @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
  25737. Command which will be invoked to format commit messages.
  25738. Defaults to @samp{""}.
  25739. @end deftypevr
  25740. @deftypevr {@code{cgit-configuration} parameter} string commit-sort
  25741. Flag which, when set to @samp{date}, enables strict date ordering in the
  25742. commit log, and when set to @samp{topo} enables strict topological
  25743. ordering.
  25744. Defaults to @samp{"git log"}.
  25745. @end deftypevr
  25746. @deftypevr {@code{cgit-configuration} parameter} file-object css
  25747. URL which specifies the css document to include in all cgit pages.
  25748. Defaults to @samp{"/share/cgit/cgit.css"}.
  25749. @end deftypevr
  25750. @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
  25751. Specifies a command which will be invoked to format names and email
  25752. address of committers, authors, and taggers, as represented in various
  25753. places throughout the cgit interface.
  25754. Defaults to @samp{""}.
  25755. @end deftypevr
  25756. @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
  25757. Flag which, when set to @samp{#t}, will make cgit generate a HTML
  25758. fragment suitable for embedding in other HTML pages.
  25759. Defaults to @samp{#f}.
  25760. @end deftypevr
  25761. @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
  25762. Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
  25763. commit history graph to the left of the commit messages in the
  25764. repository log page.
  25765. Defaults to @samp{#f}.
  25766. @end deftypevr
  25767. @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
  25768. Flag which, when set to @samp{#t}, allows all filter settings to be
  25769. overridden in repository-specific cgitrc files.
  25770. Defaults to @samp{#f}.
  25771. @end deftypevr
  25772. @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
  25773. Flag which, when set to @samp{#t}, allows users to follow a file in the
  25774. log view.
  25775. Defaults to @samp{#f}.
  25776. @end deftypevr
  25777. @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
  25778. If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
  25779. clones.
  25780. Defaults to @samp{#t}.
  25781. @end deftypevr
  25782. @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
  25783. Flag which, when set to @samp{#t}, will make cgit generate extra links
  25784. "summary", "commit", "tree" for each repo in the repository index.
  25785. Defaults to @samp{#f}.
  25786. @end deftypevr
  25787. @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
  25788. Flag which, when set to @samp{#t}, will make cgit display the owner of
  25789. each repo in the repository index.
  25790. Defaults to @samp{#t}.
  25791. @end deftypevr
  25792. @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
  25793. Flag which, when set to @samp{#t}, will make cgit print the number of
  25794. modified files for each commit on the repository log page.
  25795. Defaults to @samp{#f}.
  25796. @end deftypevr
  25797. @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
  25798. Flag which, when set to @samp{#t}, will make cgit print the number of
  25799. added and removed lines for each commit on the repository log page.
  25800. Defaults to @samp{#f}.
  25801. @end deftypevr
  25802. @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
  25803. Flag which, when set to @code{#t}, will make cgit display remote
  25804. branches in the summary and refs views.
  25805. Defaults to @samp{#f}.
  25806. @end deftypevr
  25807. @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
  25808. Flag which, when set to @code{1}, will make cgit use the subject of the
  25809. parent commit as link text when generating links to parent commits in
  25810. commit view.
  25811. Defaults to @samp{#f}.
  25812. @end deftypevr
  25813. @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
  25814. Flag which, when set to @samp{#t}, will make cgit use the subject of the
  25815. parent commit as link text when generating links to parent commits in
  25816. commit view.
  25817. Defaults to @samp{#f}.
  25818. @end deftypevr
  25819. @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
  25820. Flag which, when set to @samp{#t}, will make cgit generate linenumber
  25821. links for plaintext blobs printed in the tree view.
  25822. Defaults to @samp{#t}.
  25823. @end deftypevr
  25824. @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
  25825. Flag which, when set to @samp{#f}, will allow cgit to use Git config to
  25826. set any repo specific settings.
  25827. Defaults to @samp{#f}.
  25828. @end deftypevr
  25829. @deftypevr {@code{cgit-configuration} parameter} file-object favicon
  25830. URL used as link to a shortcut icon for cgit.
  25831. Defaults to @samp{"/favicon.ico"}.
  25832. @end deftypevr
  25833. @deftypevr {@code{cgit-configuration} parameter} string footer
  25834. The content of the file specified with this option will be included
  25835. verbatim at the bottom of all pages (i.e.@: it replaces the standard
  25836. "generated by..."@: message).
  25837. Defaults to @samp{""}.
  25838. @end deftypevr
  25839. @deftypevr {@code{cgit-configuration} parameter} string head-include
  25840. The content of the file specified with this option will be included
  25841. verbatim in the HTML HEAD section on all pages.
  25842. Defaults to @samp{""}.
  25843. @end deftypevr
  25844. @deftypevr {@code{cgit-configuration} parameter} string header
  25845. The content of the file specified with this option will be included
  25846. verbatim at the top of all pages.
  25847. Defaults to @samp{""}.
  25848. @end deftypevr
  25849. @deftypevr {@code{cgit-configuration} parameter} file-object include
  25850. Name of a configfile to include before the rest of the current config-
  25851. file is parsed.
  25852. Defaults to @samp{""}.
  25853. @end deftypevr
  25854. @deftypevr {@code{cgit-configuration} parameter} string index-header
  25855. The content of the file specified with this option will be included
  25856. verbatim above the repository index.
  25857. Defaults to @samp{""}.
  25858. @end deftypevr
  25859. @deftypevr {@code{cgit-configuration} parameter} string index-info
  25860. The content of the file specified with this option will be included
  25861. verbatim below the heading on the repository index page.
  25862. Defaults to @samp{""}.
  25863. @end deftypevr
  25864. @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
  25865. Flag which, if set to @samp{#t}, makes cgit print commit and tag times
  25866. in the servers timezone.
  25867. Defaults to @samp{#f}.
  25868. @end deftypevr
  25869. @deftypevr {@code{cgit-configuration} parameter} file-object logo
  25870. URL which specifies the source of an image which will be used as a logo
  25871. on all cgit pages.
  25872. Defaults to @samp{"/share/cgit/cgit.png"}.
  25873. @end deftypevr
  25874. @deftypevr {@code{cgit-configuration} parameter} string logo-link
  25875. URL loaded when clicking on the cgit logo image.
  25876. Defaults to @samp{""}.
  25877. @end deftypevr
  25878. @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
  25879. Command which will be invoked to format the Owner column of the main
  25880. page.
  25881. Defaults to @samp{""}.
  25882. @end deftypevr
  25883. @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
  25884. Number of items to display in atom feeds view.
  25885. Defaults to @samp{10}.
  25886. @end deftypevr
  25887. @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
  25888. Number of entries to list per page in "log" view.
  25889. Defaults to @samp{50}.
  25890. @end deftypevr
  25891. @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
  25892. Number of commit message characters to display in "log" view.
  25893. Defaults to @samp{80}.
  25894. @end deftypevr
  25895. @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
  25896. Specifies the number of entries to list per page on the repository index
  25897. page.
  25898. Defaults to @samp{50}.
  25899. @end deftypevr
  25900. @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
  25901. Specifies the maximum number of repo description characters to display
  25902. on the repository index page.
  25903. Defaults to @samp{80}.
  25904. @end deftypevr
  25905. @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
  25906. Specifies the maximum size of a blob to display HTML for in KBytes.
  25907. Defaults to @samp{0}.
  25908. @end deftypevr
  25909. @deftypevr {@code{cgit-configuration} parameter} string max-stats
  25910. Maximum statistics period. Valid values are @samp{week},@samp{month},
  25911. @samp{quarter} and @samp{year}.
  25912. Defaults to @samp{""}.
  25913. @end deftypevr
  25914. @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
  25915. Mimetype for the specified filename extension.
  25916. Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
  25917. "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
  25918. "image/png") (svg "image/svg+xml"))}.
  25919. @end deftypevr
  25920. @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
  25921. Specifies the file to use for automatic mimetype lookup.
  25922. Defaults to @samp{""}.
  25923. @end deftypevr
  25924. @deftypevr {@code{cgit-configuration} parameter} string module-link
  25925. Text which will be used as the formatstring for a hyperlink when a
  25926. submodule is printed in a directory listing.
  25927. Defaults to @samp{""}.
  25928. @end deftypevr
  25929. @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
  25930. If set to the value @samp{#t} caching will be disabled.
  25931. Defaults to @samp{#f}.
  25932. @end deftypevr
  25933. @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
  25934. If set to @samp{#t} showing full author email addresses will be
  25935. disabled.
  25936. Defaults to @samp{#f}.
  25937. @end deftypevr
  25938. @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
  25939. Flag which, when set to @samp{#t}, will make cgit omit the standard
  25940. header on all pages.
  25941. Defaults to @samp{#f}.
  25942. @end deftypevr
  25943. @deftypevr {@code{cgit-configuration} parameter} project-list project-list
  25944. A list of subdirectories inside of @code{repository-directory}, relative
  25945. to it, that should loaded as Git repositories. An empty list means that
  25946. all subdirectories will be loaded.
  25947. Defaults to @samp{()}.
  25948. @end deftypevr
  25949. @deftypevr {@code{cgit-configuration} parameter} file-object readme
  25950. Text which will be used as default value for @code{cgit-repo-readme}.
  25951. Defaults to @samp{""}.
  25952. @end deftypevr
  25953. @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
  25954. If set to @code{#t} and @code{repository-directory} is enabled, if any
  25955. repositories are found with a suffix of @code{.git}, this suffix will be
  25956. removed for the URL and name.
  25957. Defaults to @samp{#f}.
  25958. @end deftypevr
  25959. @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
  25960. Maximum number of files to consider when detecting renames.
  25961. Defaults to @samp{-1}.
  25962. @end deftypevr
  25963. @deftypevr {@code{cgit-configuration} parameter} string repository-sort
  25964. The way in which repositories in each section are sorted.
  25965. Defaults to @samp{""}.
  25966. @end deftypevr
  25967. @deftypevr {@code{cgit-configuration} parameter} robots-list robots
  25968. Text used as content for the @code{robots} meta-tag.
  25969. Defaults to @samp{("noindex" "nofollow")}.
  25970. @end deftypevr
  25971. @deftypevr {@code{cgit-configuration} parameter} string root-desc
  25972. Text printed below the heading on the repository index page.
  25973. Defaults to @samp{"a fast webinterface for the git dscm"}.
  25974. @end deftypevr
  25975. @deftypevr {@code{cgit-configuration} parameter} string root-readme
  25976. The content of the file specified with this option will be included
  25977. verbatim below the ``about'' link on the repository index page.
  25978. Defaults to @samp{""}.
  25979. @end deftypevr
  25980. @deftypevr {@code{cgit-configuration} parameter} string root-title
  25981. Text printed as heading on the repository index page.
  25982. Defaults to @samp{""}.
  25983. @end deftypevr
  25984. @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
  25985. If set to @samp{#t} and repository-directory is enabled,
  25986. repository-directory will recurse into directories whose name starts
  25987. with a period. Otherwise, repository-directory will stay away from such
  25988. directories, considered as ``hidden''. Note that this does not apply to
  25989. the @file{.git} directory in non-bare repos.
  25990. Defaults to @samp{#f}.
  25991. @end deftypevr
  25992. @deftypevr {@code{cgit-configuration} parameter} list snapshots
  25993. Text which specifies the default set of snapshot formats that cgit
  25994. generates links for.
  25995. Defaults to @samp{()}.
  25996. @end deftypevr
  25997. @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
  25998. Name of the directory to scan for repositories (represents
  25999. @code{scan-path}).
  26000. Defaults to @samp{"/srv/git"}.
  26001. @end deftypevr
  26002. @deftypevr {@code{cgit-configuration} parameter} string section
  26003. The name of the current repository section - all repositories defined
  26004. after this option will inherit the current section name.
  26005. Defaults to @samp{""}.
  26006. @end deftypevr
  26007. @deftypevr {@code{cgit-configuration} parameter} string section-sort
  26008. Flag which, when set to @samp{1}, will sort the sections on the
  26009. repository listing by name.
  26010. Defaults to @samp{""}.
  26011. @end deftypevr
  26012. @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
  26013. A number which, if defined prior to repository-directory, specifies how
  26014. many path elements from each repo path to use as a default section name.
  26015. Defaults to @samp{0}.
  26016. @end deftypevr
  26017. @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
  26018. If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
  26019. default.
  26020. Defaults to @samp{#f}.
  26021. @end deftypevr
  26022. @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
  26023. Specifies a command which will be invoked to format plaintext blobs in
  26024. the tree view.
  26025. Defaults to @samp{""}.
  26026. @end deftypevr
  26027. @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
  26028. Specifies the number of branches to display in the repository ``summary''
  26029. view.
  26030. Defaults to @samp{10}.
  26031. @end deftypevr
  26032. @deftypevr {@code{cgit-configuration} parameter} integer summary-log
  26033. Specifies the number of log entries to display in the repository
  26034. ``summary'' view.
  26035. Defaults to @samp{10}.
  26036. @end deftypevr
  26037. @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
  26038. Specifies the number of tags to display in the repository ``summary''
  26039. view.
  26040. Defaults to @samp{10}.
  26041. @end deftypevr
  26042. @deftypevr {@code{cgit-configuration} parameter} string strict-export
  26043. Filename which, if specified, needs to be present within the repository
  26044. for cgit to allow access to that repository.
  26045. Defaults to @samp{""}.
  26046. @end deftypevr
  26047. @deftypevr {@code{cgit-configuration} parameter} string virtual-root
  26048. URL which, if specified, will be used as root for all cgit links.
  26049. Defaults to @samp{"/"}.
  26050. @end deftypevr
  26051. @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
  26052. A list of @dfn{cgit-repo} records to use with config.
  26053. Defaults to @samp{()}.
  26054. Available @code{repository-cgit-configuration} fields are:
  26055. @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
  26056. A mask of snapshot formats for this repo that cgit generates links for,
  26057. restricted by the global @code{snapshots} setting.
  26058. Defaults to @samp{()}.
  26059. @end deftypevr
  26060. @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
  26061. Override the default @code{source-filter}.
  26062. Defaults to @samp{""}.
  26063. @end deftypevr
  26064. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
  26065. The relative URL used to access the repository.
  26066. Defaults to @samp{""}.
  26067. @end deftypevr
  26068. @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
  26069. Override the default @code{about-filter}.
  26070. Defaults to @samp{""}.
  26071. @end deftypevr
  26072. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
  26073. Flag which, when set to @samp{age}, enables date ordering in the branch
  26074. ref list, and when set to @samp{name} enables ordering by branch name.
  26075. Defaults to @samp{""}.
  26076. @end deftypevr
  26077. @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
  26078. A list of URLs which can be used to clone repo.
  26079. Defaults to @samp{()}.
  26080. @end deftypevr
  26081. @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
  26082. Override the default @code{commit-filter}.
  26083. Defaults to @samp{""}.
  26084. @end deftypevr
  26085. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
  26086. Flag which, when set to @samp{date}, enables strict date ordering in the
  26087. commit log, and when set to @samp{topo} enables strict topological
  26088. ordering.
  26089. Defaults to @samp{""}.
  26090. @end deftypevr
  26091. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
  26092. The name of the default branch for this repository. If no such branch
  26093. exists in the repository, the first branch name (when sorted) is used as
  26094. default instead. By default branch pointed to by HEAD, or ``master'' if
  26095. there is no suitable HEAD.
  26096. Defaults to @samp{""}.
  26097. @end deftypevr
  26098. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
  26099. The value to show as repository description.
  26100. Defaults to @samp{""}.
  26101. @end deftypevr
  26102. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
  26103. The value to show as repository homepage.
  26104. Defaults to @samp{""}.
  26105. @end deftypevr
  26106. @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
  26107. Override the default @code{email-filter}.
  26108. Defaults to @samp{""}.
  26109. @end deftypevr
  26110. @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
  26111. A flag which can be used to disable the global setting
  26112. @code{enable-commit-graph?}.
  26113. Defaults to @samp{disabled}.
  26114. @end deftypevr
  26115. @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
  26116. A flag which can be used to disable the global setting
  26117. @code{enable-log-filecount?}.
  26118. Defaults to @samp{disabled}.
  26119. @end deftypevr
  26120. @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
  26121. A flag which can be used to disable the global setting
  26122. @code{enable-log-linecount?}.
  26123. Defaults to @samp{disabled}.
  26124. @end deftypevr
  26125. @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
  26126. Flag which, when set to @code{#t}, will make cgit display remote
  26127. branches in the summary and refs views.
  26128. Defaults to @samp{disabled}.
  26129. @end deftypevr
  26130. @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
  26131. A flag which can be used to override the global setting
  26132. @code{enable-subject-links?}.
  26133. Defaults to @samp{disabled}.
  26134. @end deftypevr
  26135. @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
  26136. A flag which can be used to override the global setting
  26137. @code{enable-html-serving?}.
  26138. Defaults to @samp{disabled}.
  26139. @end deftypevr
  26140. @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
  26141. Flag which, when set to @code{#t}, hides the repository from the
  26142. repository index.
  26143. Defaults to @samp{#f}.
  26144. @end deftypevr
  26145. @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
  26146. Flag which, when set to @samp{#t}, ignores the repository.
  26147. Defaults to @samp{#f}.
  26148. @end deftypevr
  26149. @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
  26150. URL which specifies the source of an image which will be used as a logo
  26151. on this repo’s pages.
  26152. Defaults to @samp{""}.
  26153. @end deftypevr
  26154. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
  26155. URL loaded when clicking on the cgit logo image.
  26156. Defaults to @samp{""}.
  26157. @end deftypevr
  26158. @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
  26159. Override the default @code{owner-filter}.
  26160. Defaults to @samp{""}.
  26161. @end deftypevr
  26162. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
  26163. Text which will be used as the formatstring for a hyperlink when a
  26164. submodule is printed in a directory listing. The arguments for the
  26165. formatstring are the path and SHA1 of the submodule commit.
  26166. Defaults to @samp{""}.
  26167. @end deftypevr
  26168. @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
  26169. Text which will be used as the formatstring for a hyperlink when a
  26170. submodule with the specified subdirectory path is printed in a directory
  26171. listing.
  26172. Defaults to @samp{()}.
  26173. @end deftypevr
  26174. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
  26175. Override the default maximum statistics period.
  26176. Defaults to @samp{""}.
  26177. @end deftypevr
  26178. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
  26179. The value to show as repository name.
  26180. Defaults to @samp{""}.
  26181. @end deftypevr
  26182. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
  26183. A value used to identify the owner of the repository.
  26184. Defaults to @samp{""}.
  26185. @end deftypevr
  26186. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
  26187. An absolute path to the repository directory.
  26188. Defaults to @samp{""}.
  26189. @end deftypevr
  26190. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
  26191. A path (relative to repo) which specifies a file to include verbatim as
  26192. the ``About'' page for this repo.
  26193. Defaults to @samp{""}.
  26194. @end deftypevr
  26195. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
  26196. The name of the current repository section - all repositories defined
  26197. after this option will inherit the current section name.
  26198. Defaults to @samp{""}.
  26199. @end deftypevr
  26200. @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
  26201. Extra options will be appended to cgitrc file.
  26202. Defaults to @samp{()}.
  26203. @end deftypevr
  26204. @end deftypevr
  26205. @deftypevr {@code{cgit-configuration} parameter} list extra-options
  26206. Extra options will be appended to cgitrc file.
  26207. Defaults to @samp{()}.
  26208. @end deftypevr
  26209. @c %end of fragment
  26210. However, it could be that you just want to get a @code{cgitrc} up and
  26211. running. In that case, you can pass an @code{opaque-cgit-configuration}
  26212. as a record to @code{cgit-service-type}. As its name indicates, an
  26213. opaque configuration does not have easy reflective capabilities.
  26214. Available @code{opaque-cgit-configuration} fields are:
  26215. @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
  26216. The cgit package.
  26217. @end deftypevr
  26218. @deftypevr {@code{opaque-cgit-configuration} parameter} string string
  26219. The contents of the @code{cgitrc}, as a string.
  26220. @end deftypevr
  26221. For example, if your @code{cgitrc} is just the empty string, you
  26222. could instantiate a cgit service like this:
  26223. @lisp
  26224. (service cgit-service-type
  26225. (opaque-cgit-configuration
  26226. (cgitrc "")))
  26227. @end lisp
  26228. @subsubheading Gitolite Service
  26229. @cindex Gitolite service
  26230. @cindex Git, hosting
  26231. @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
  26232. repositories on a central server.
  26233. Gitolite can handle multiple repositories and users, and supports flexible
  26234. configuration of the permissions for the users on the repositories.
  26235. The following example will configure Gitolite using the default @code{git}
  26236. user, and the provided SSH public key.
  26237. @lisp
  26238. (service gitolite-service-type
  26239. (gitolite-configuration
  26240. (admin-pubkey (plain-file
  26241. "yourname.pub"
  26242. "ssh-rsa AAAA... guix@@example.com"))))
  26243. @end lisp
  26244. Gitolite is configured through a special admin repository which you can clone,
  26245. for example, if you setup Gitolite on @code{example.com}, you would run the
  26246. following command to clone the admin repository.
  26247. @example
  26248. git clone git@@example.com:gitolite-admin
  26249. @end example
  26250. When the Gitolite service is activated, the provided @code{admin-pubkey} will
  26251. be inserted in to the @file{keydir} directory in the gitolite-admin
  26252. repository. If this results in a change in the repository, it will be
  26253. committed using the message ``gitolite setup by GNU Guix''.
  26254. @deftp {Data Type} gitolite-configuration
  26255. Data type representing the configuration for @code{gitolite-service-type}.
  26256. @table @asis
  26257. @item @code{package} (default: @var{gitolite})
  26258. Gitolite package to use.
  26259. @item @code{user} (default: @var{git})
  26260. User to use for Gitolite. This will be user that you use when accessing
  26261. Gitolite over SSH.
  26262. @item @code{group} (default: @var{git})
  26263. Group to use for Gitolite.
  26264. @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
  26265. Directory in which to store the Gitolite configuration and repositories.
  26266. @item @code{rc-file} (default: @var{(gitolite-rc-file)})
  26267. A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
  26268. representing the configuration for Gitolite.
  26269. @item @code{admin-pubkey} (default: @var{#f})
  26270. A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
  26271. setup Gitolite. This will be inserted in to the @file{keydir} directory
  26272. within the gitolite-admin repository.
  26273. To specify the SSH key as a string, use the @code{plain-file} function.
  26274. @lisp
  26275. (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
  26276. @end lisp
  26277. @end table
  26278. @end deftp
  26279. @deftp {Data Type} gitolite-rc-file
  26280. Data type representing the Gitolite RC file.
  26281. @table @asis
  26282. @item @code{umask} (default: @code{#o0077})
  26283. This controls the permissions Gitolite sets on the repositories and their
  26284. contents.
  26285. A value like @code{#o0027} will give read access to the group used by Gitolite
  26286. (by default: @code{git}). This is necessary when using Gitolite with software
  26287. like cgit or gitweb.
  26288. @item @code{unsafe-pattern} (default: @code{#f})
  26289. An optional Perl regular expression for catching unsafe configurations in
  26290. the configuration file. See
  26291. @uref{https://gitolite.com/gitolite/git-config.html#compensating-for-unsafe_patt,
  26292. Gitolite's documentation} for more information.
  26293. When the value is not @code{#f}, it should be a string containing a Perl
  26294. regular expression, such as @samp{"[`~#\$\&()|;<>]"}, which is the default
  26295. value used by gitolite. It rejects any special character in configuration
  26296. that might be interpreted by a shell, which is useful when sharing the
  26297. administration burden with other people that do not otherwise have shell
  26298. access on the server.
  26299. @item @code{git-config-keys} (default: @code{""})
  26300. Gitolite allows you to set git config values using the @samp{config}
  26301. keyword. This setting allows control over the config keys to accept.
  26302. @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
  26303. Set the role names allowed to be used by users running the perms command.
  26304. @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
  26305. This setting controls the commands and features to enable within Gitolite.
  26306. @end table
  26307. @end deftp
  26308. @subsubheading Gitile Service
  26309. @cindex Gitile service
  26310. @cindex Git, forge
  26311. @uref{https://git.lepiller.eu/gitile, Gitile} is a Git forge for viewing
  26312. public git repository contents from a web browser.
  26313. Gitile works best in collaboration with Gitolite, and will serve the public
  26314. repositories from Gitolite by default. The service should listen only on
  26315. a local port, and a webserver should be configured to serve static resources.
  26316. The gitile service provides an easy way to extend the Nginx service for
  26317. that purpose (@pxref{NGINX}).
  26318. The following example will configure Gitile to serve repositories from a
  26319. custom location, with some default messages for the home page and the
  26320. footers.
  26321. @lisp
  26322. (service gitile-service-type
  26323. (gitile-configuration
  26324. (repositories "/srv/git")
  26325. (base-git-url "https://myweb.site/git")
  26326. (index-title "My git repositories")
  26327. (intro '((p "This is all my public work!")))
  26328. (footer '((p "This is the end")))
  26329. (nginx-server-block
  26330. (nginx-server-configuration
  26331. (ssl-certificate
  26332. "/etc/letsencrypt/live/myweb.site/fullchain.pem")
  26333. (ssl-certificate-key
  26334. "/etc/letsencrypt/live/myweb.site/privkey.pem")
  26335. (listen '("443 ssl http2" "[::]:443 ssl http2"))
  26336. (locations
  26337. (list
  26338. ;; Allow for https anonymous fetch on /git/ urls.
  26339. (git-http-nginx-location-configuration
  26340. (git-http-configuration
  26341. (uri-path "/git/")
  26342. (git-root "/var/lib/gitolite/repositories")))))))))
  26343. @end lisp
  26344. In addition to the configuration record, you should configure your git
  26345. repositories to contain some optional information. First, your public
  26346. repositories need to contain the @file{git-daemon-export-ok} magic file
  26347. that allows Git to export the repository. Gitile uses the presence of this
  26348. file to detect public repositories it should make accessible. To do so with
  26349. Gitolite for instance, modify your @file{conf/gitolite.conf} to include
  26350. this in the repositories you want to make public:
  26351. @example
  26352. repo foo
  26353. R = daemon
  26354. @end example
  26355. In addition, Gitile can read the repository configuration to display more
  26356. information on the repository. Gitile uses the gitweb namespace for its
  26357. configuration. As an example, you can use the following in your
  26358. @file{conf/gitolite.conf}:
  26359. @example
  26360. repo foo
  26361. R = daemon
  26362. desc = A long description, optionally with <i>HTML</i>, shown on the index page
  26363. config gitweb.name = The Foo Project
  26364. config gitweb.synopsis = A short description, shown on the main page of the project
  26365. @end example
  26366. Do not forget to commit and push these changes once you are satisfied. You
  26367. may need to change your gitolite configuration to allow the previous
  26368. configuration options to be set. One way to do that is to add the
  26369. following service definition:
  26370. @lisp
  26371. (service gitolite-service-type
  26372. (gitolite-configuration
  26373. (admin-pubkey (local-file "key.pub"))
  26374. (rc-file
  26375. (gitolite-rc-file
  26376. (umask #o0027)
  26377. ;; Allow to set any configuration key
  26378. (git-config-keys ".*")
  26379. ;; Allow any text as a valid configuration value
  26380. (unsafe-patt "^$")))))
  26381. @end lisp
  26382. @deftp {Data Type} gitile-configuration
  26383. Data type representing the configuration for @code{gitile-service-type}.
  26384. @table @asis
  26385. @item @code{package} (default: @var{gitile})
  26386. Gitile package to use.
  26387. @item @code{host} (default: @code{"localhost"})
  26388. The host on which gitile is listening.
  26389. @item @code{port} (default: @code{8080})
  26390. The port on which gitile is listening.
  26391. @item @code{database} (default: @code{"/var/lib/gitile/gitile-db.sql"})
  26392. The location of the database.
  26393. @item @code{repositories} (default: @code{"/var/lib/gitolite/repositories"})
  26394. The location of the repositories. Note that only public repositories will
  26395. be shown by Gitile. To make a repository public, add an empty
  26396. @file{git-daemon-export-ok} file at the root of that repository.
  26397. @item @code{base-git-url}
  26398. The base git url that will be used to show clone commands.
  26399. @item @code{index-title} (default: @code{"Index"})
  26400. The page title for the index page that lists all the available repositories.
  26401. @item @code{intro} (default: @code{'()})
  26402. The intro content, as a list of sxml expressions. This is shown above the list
  26403. of repositories, on the index page.
  26404. @item @code{footer} (default: @code{'()})
  26405. The footer content, as a list of sxml expressions. This is shown on every
  26406. page served by Gitile.
  26407. @item @code{nginx-server-block}
  26408. An nginx server block that will be extended and used as a reverse proxy by
  26409. Gitile to serve its pages, and as a normal web server to serve its assets.
  26410. You can use this block to add more custom URLs to your domain, such as a
  26411. @code{/git/} URL for anonymous clones, or serving any other files you would
  26412. like to serve.
  26413. @end table
  26414. @end deftp
  26415. @node Game Services
  26416. @subsection Game Services
  26417. @subsubheading The Battle for Wesnoth Service
  26418. @cindex wesnothd
  26419. @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
  26420. based tactical strategy game, with several single player campaigns, and
  26421. multiplayer games (both networked and local).
  26422. @defvar {Scheme Variable} wesnothd-service-type
  26423. Service type for the wesnothd service. Its value must be a
  26424. @code{wesnothd-configuration} object. To run wesnothd in the default
  26425. configuration, instantiate it as:
  26426. @lisp
  26427. (service wesnothd-service-type)
  26428. @end lisp
  26429. @end defvar
  26430. @deftp {Data Type} wesnothd-configuration
  26431. Data type representing the configuration of @command{wesnothd}.
  26432. @table @asis
  26433. @item @code{package} (default: @code{wesnoth-server})
  26434. The wesnoth server package to use.
  26435. @item @code{port} (default: @code{15000})
  26436. The port to bind the server to.
  26437. @end table
  26438. @end deftp
  26439. @node PAM Mount Service
  26440. @subsection PAM Mount Service
  26441. @cindex pam-mount
  26442. The @code{(gnu services pam-mount)} module provides a service allowing
  26443. users to mount volumes when they log in. It should be able to mount any
  26444. volume format supported by the system.
  26445. @defvar {Scheme Variable} pam-mount-service-type
  26446. Service type for PAM Mount support.
  26447. @end defvar
  26448. @deftp {Data Type} pam-mount-configuration
  26449. Data type representing the configuration of PAM Mount.
  26450. It takes the following parameters:
  26451. @table @asis
  26452. @item @code{rules}
  26453. The configuration rules that will be used to generate
  26454. @file{/etc/security/pam_mount.conf.xml}.
  26455. The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
  26456. Guile Reference Manual}), and the default ones don't mount anything for
  26457. anyone at login:
  26458. @lisp
  26459. `((debug (@@ (enable "0")))
  26460. (mntoptions (@@ (allow ,(string-join
  26461. '("nosuid" "nodev" "loop"
  26462. "encryption" "fsck" "nonempty"
  26463. "allow_root" "allow_other")
  26464. ","))))
  26465. (mntoptions (@@ (require "nosuid,nodev")))
  26466. (logout (@@ (wait "0")
  26467. (hup "0")
  26468. (term "no")
  26469. (kill "no")))
  26470. (mkmountpoint (@@ (enable "1")
  26471. (remove "true"))))
  26472. @end lisp
  26473. Some @code{volume} elements must be added to automatically mount volumes
  26474. at login. Here's an example allowing the user @code{alice} to mount her
  26475. encrypted @env{HOME} directory and allowing the user @code{bob} to mount
  26476. the partition where he stores his data:
  26477. @lisp
  26478. (define pam-mount-rules
  26479. `((debug (@@ (enable "0")))
  26480. (volume (@@ (user "alice")
  26481. (fstype "crypt")
  26482. (path "/dev/sda2")
  26483. (mountpoint "/home/alice")))
  26484. (volume (@@ (user "bob")
  26485. (fstype "auto")
  26486. (path "/dev/sdb3")
  26487. (mountpoint "/home/bob/data")
  26488. (options "defaults,autodefrag,compress")))
  26489. (mntoptions (@@ (allow ,(string-join
  26490. '("nosuid" "nodev" "loop"
  26491. "encryption" "fsck" "nonempty"
  26492. "allow_root" "allow_other")
  26493. ","))))
  26494. (mntoptions (@@ (require "nosuid,nodev")))
  26495. (logout (@@ (wait "0")
  26496. (hup "0")
  26497. (term "no")
  26498. (kill "no")))
  26499. (mkmountpoint (@@ (enable "1")
  26500. (remove "true")))))
  26501. (service pam-mount-service-type
  26502. (pam-mount-configuration
  26503. (rules pam-mount-rules)))
  26504. @end lisp
  26505. The complete list of possible options can be found in the man page for
  26506. @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
  26507. @end table
  26508. @end deftp
  26509. @node Guix Services
  26510. @subsection Guix Services
  26511. @subsubheading Guix Build Coordinator
  26512. The @uref{https://git.cbaines.net/guix/build-coordinator/,Guix Build
  26513. Coordinator} aids in distributing derivation builds among machines
  26514. running an @dfn{agent}. The build daemon is still used to build the
  26515. derivations, but the Guix Build Coordinator manages allocating builds
  26516. and working with the results.
  26517. The Guix Build Coordinator consists of one @dfn{coordinator}, and one or
  26518. more connected @dfn{agent} processes. The coordinator process handles
  26519. clients submitting builds, and allocating builds to agents. The agent
  26520. processes talk to a build daemon to actually perform the builds, then
  26521. send the results back to the coordinator.
  26522. There is a script to run the coordinator component of the Guix Build
  26523. Coordinator, but the Guix service uses a custom Guile script instead, to
  26524. provide better integration with G-expressions used in the configuration.
  26525. @defvar {Scheme Variable} guix-build-coordinator-service-type
  26526. Service type for the Guix Build Coordinator. Its value must be a
  26527. @code{guix-build-coordinator-configuration} object.
  26528. @end defvar
  26529. @deftp {Data Type} guix-build-coordinator-configuration
  26530. Data type representing the configuration of the Guix Build Coordinator.
  26531. @table @asis
  26532. @item @code{package} (default: @code{guix-build-coordinator})
  26533. The Guix Build Coordinator package to use.
  26534. @item @code{user} (default: @code{"guix-build-coordinator"})
  26535. The system user to run the service as.
  26536. @item @code{group} (default: @code{"guix-build-coordinator"})
  26537. The system group to run the service as.
  26538. @item @code{database-uri-string} (default: @code{"sqlite:///var/lib/guix-build-coordinator/guix_build_coordinator.db"})
  26539. The URI to use for the database.
  26540. @item @code{agent-communication-uri} (default: @code{"http://0.0.0.0:8745"})
  26541. The URI describing how to listen to requests from agent processes.
  26542. @item @code{client-communication-uri} (default: @code{"http://127.0.0.1:8746"})
  26543. The URI describing how to listen to requests from clients. The client
  26544. API allows submitting builds and currently isn't authenticated, so take
  26545. care when configuring this value.
  26546. @item @code{allocation-strategy} (default: @code{#~basic-build-allocation-strategy})
  26547. A G-expression for the allocation strategy to be used. This is a
  26548. procedure that takes the datastore as an argument and populates the
  26549. allocation plan in the database.
  26550. @item @code{hooks} (default: @var{'()})
  26551. An association list of hooks. These provide a way to execute arbitrary
  26552. code upon certain events, like a build result being processed.
  26553. @item @code{guile} (default: @code{guile-3.0-latest})
  26554. The Guile package with which to run the Guix Build Coordinator.
  26555. @end table
  26556. @end deftp
  26557. @defvar {Scheme Variable} guix-build-coordinator-agent-service-type
  26558. Service type for a Guix Build Coordinator agent. Its value must be a
  26559. @code{guix-build-coordinator-agent-configuration} object.
  26560. @end defvar
  26561. @deftp {Data Type} guix-build-coordinator-agent-configuration
  26562. Data type representing the configuration a Guix Build Coordinator agent.
  26563. @table @asis
  26564. @item @code{package} (default: @code{guix-build-coordinator/agent-only})
  26565. The Guix Build Coordinator package to use.
  26566. @item @code{user} (default: @code{"guix-build-coordinator-agent"})
  26567. The system user to run the service as.
  26568. @item @code{coordinator} (default: @code{"http://localhost:8745"})
  26569. The URI to use when connecting to the coordinator.
  26570. @item @code{authentication}
  26571. Record describing how this agent should authenticate with the
  26572. coordinator. Possible record types are described below.
  26573. @item @code{systems} (default: @code{#f})
  26574. The systems for which this agent should fetch builds. The agent process
  26575. will use the current system it's running on as the default.
  26576. @item @code{max-parallel-builds} (default: @code{1})
  26577. The number of builds to perform in parallel.
  26578. @item @code{max-1min-load-average} (default: @code{#f})
  26579. Load average value to look at when considering starting new builds, if
  26580. the 1 minute load average exceeds this value, the agent will wait before
  26581. starting new builds.
  26582. This will be unspecified if the value is @code{#f}, and the agent will
  26583. use the number of cores reported by the system as the max 1 minute load
  26584. average.
  26585. @item @code{derivation-substitute-urls} (default: @code{#f})
  26586. URLs from which to attempt to fetch substitutes for derivations, if the
  26587. derivations aren't already available.
  26588. @item @code{non-derivation-substitute-urls} (default: @code{#f})
  26589. URLs from which to attempt to fetch substitutes for build inputs, if the
  26590. input store items aren't already available.
  26591. @end table
  26592. @end deftp
  26593. @deftp {Data Type} guix-build-coordinator-agent-password-auth
  26594. Data type representing an agent authenticating with a coordinator via a
  26595. UUID and password.
  26596. @table @asis
  26597. @item @code{uuid}
  26598. The UUID of the agent. This should be generated by the coordinator
  26599. process, stored in the coordinator database, and used by the intended
  26600. agent.
  26601. @item @code{password}
  26602. The password to use when connecting to the coordinator.
  26603. @end table
  26604. @end deftp
  26605. @deftp {Data Type} guix-build-coordinator-agent-password-file-auth
  26606. Data type representing an agent authenticating with a coordinator via a
  26607. UUID and password read from a file.
  26608. @table @asis
  26609. @item @code{uuid}
  26610. The UUID of the agent. This should be generated by the coordinator
  26611. process, stored in the coordinator database, and used by the intended
  26612. agent.
  26613. @item @code{password-file}
  26614. A file containing the password to use when connecting to the
  26615. coordinator.
  26616. @end table
  26617. @end deftp
  26618. @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth
  26619. Data type representing an agent authenticating with a coordinator via a
  26620. dynamic auth token and agent name.
  26621. @table @asis
  26622. @item @code{agent-name}
  26623. Name of an agent, this is used to match up to an existing entry in the
  26624. database if there is one. When no existing entry is found, a new entry
  26625. is automatically added.
  26626. @item @code{token}
  26627. Dynamic auth token, this is created and stored in the coordinator
  26628. database, and is used by the agent to authenticate.
  26629. @end table
  26630. @end deftp
  26631. @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth-with-file
  26632. Data type representing an agent authenticating with a coordinator via a
  26633. dynamic auth token read from a file and agent name.
  26634. @table @asis
  26635. @item @code{agent-name}
  26636. Name of an agent, this is used to match up to an existing entry in the
  26637. database if there is one. When no existing entry is found, a new entry
  26638. is automatically added.
  26639. @item @code{token-file}
  26640. File containing the dynamic auth token, this is created and stored in
  26641. the coordinator database, and is used by the agent to authenticate.
  26642. @end table
  26643. @end deftp
  26644. The Guix Build Coordinator package contains a script to query an
  26645. instance of the Guix Data Service for derivations to build, and then
  26646. submit builds for those derivations to the coordinator. The service
  26647. type below assists in running this script. This is an additional tool
  26648. that may be useful when building derivations contained within an
  26649. instance of the Guix Data Service.
  26650. @defvar {Scheme Variable} guix-build-coordinator-queue-builds-service-type
  26651. Service type for the
  26652. guix-build-coordinator-queue-builds-from-guix-data-service script. Its
  26653. value must be a @code{guix-build-coordinator-queue-builds-configuration}
  26654. object.
  26655. @end defvar
  26656. @deftp {Data Type} guix-build-coordinator-queue-builds-configuration
  26657. Data type representing the options to the queue builds from guix data
  26658. service script.
  26659. @table @asis
  26660. @item @code{package} (default: @code{guix-build-coordinator})
  26661. The Guix Build Coordinator package to use.
  26662. @item @code{user} (default: @code{"guix-build-coordinator-queue-builds"})
  26663. The system user to run the service as.
  26664. @item @code{coordinator} (default: @code{"http://localhost:8746"})
  26665. The URI to use when connecting to the coordinator.
  26666. @item @code{systems} (default: @code{#f})
  26667. The systems for which to fetch derivations to build.
  26668. @item @code{systems-and-targets} (default: @code{#f})
  26669. An association list of system and target pairs for which to fetch
  26670. derivations to build.
  26671. @item @code{guix-data-service} (default: @code{"https://data.guix.gnu.org"})
  26672. The Guix Data Service instance from which to query to find out about
  26673. derivations to build.
  26674. @item @code{processed-commits-file} (default: @code{"/var/cache/guix-build-coordinator-queue-builds/processed-commits"})
  26675. A file to record which commits have been processed, to avoid needlessly
  26676. processing them again if the service is restarted.
  26677. @end table
  26678. @end deftp
  26679. @subsubheading Guix Data Service
  26680. The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
  26681. and provides data about GNU Guix. This includes information about
  26682. packages, derivations and lint warnings.
  26683. The data is stored in a PostgreSQL database, and available through a web
  26684. interface.
  26685. @defvar {Scheme Variable} guix-data-service-type
  26686. Service type for the Guix Data Service. Its value must be a
  26687. @code{guix-data-service-configuration} object. The service optionally
  26688. extends the getmail service, as the guix-commits mailing list is used to
  26689. find out about changes in the Guix git repository.
  26690. @end defvar
  26691. @deftp {Data Type} guix-data-service-configuration
  26692. Data type representing the configuration of the Guix Data Service.
  26693. @table @asis
  26694. @item @code{package} (default: @code{guix-data-service})
  26695. The Guix Data Service package to use.
  26696. @item @code{user} (default: @code{"guix-data-service"})
  26697. The system user to run the service as.
  26698. @item @code{group} (default: @code{"guix-data-service"})
  26699. The system group to run the service as.
  26700. @item @code{port} (default: @code{8765})
  26701. The port to bind the web service to.
  26702. @item @code{host} (default: @code{"127.0.0.1"})
  26703. The host to bind the web service to.
  26704. @item @code{getmail-idle-mailboxes} (default: @code{#f})
  26705. If set, this is the list of mailboxes that the getmail service will be
  26706. configured to listen to.
  26707. @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
  26708. If set, this is the @code{getmail-retriever-configuration} object with
  26709. which to configure getmail to fetch mail from the guix-commits mailing
  26710. list.
  26711. @item @code{extra-options} (default: @var{'()})
  26712. Extra command line options for @code{guix-data-service}.
  26713. @item @code{extra-process-jobs-options} (default: @var{'()})
  26714. Extra command line options for @code{guix-data-service-process-jobs}.
  26715. @end table
  26716. @end deftp
  26717. @subsubheading Nar Herder
  26718. The @uref{https://git.cbaines.net/guix/nar-herder/about/,Nar Herder} is
  26719. a utility for managing a collection of nars.
  26720. @defvar {Scheme Variable} nar-herder-type
  26721. Service type for the Guix Data Service. Its value must be a
  26722. @code{nar-herder-configuration} object. The service optionally
  26723. extends the getmail service, as the guix-commits mailing list is used to
  26724. find out about changes in the Guix git repository.
  26725. @end defvar
  26726. @deftp {Data Type} nar-herder-configuration
  26727. Data type representing the configuration of the Guix Data Service.
  26728. @table @asis
  26729. @item @code{package} (default: @code{nar-herder})
  26730. The Nar Herder package to use.
  26731. @item @code{user} (default: @code{"nar-herder"})
  26732. The system user to run the service as.
  26733. @item @code{group} (default: @code{"nar-herder"})
  26734. The system group to run the service as.
  26735. @item @code{port} (default: @code{8734})
  26736. The port to bind the server to.
  26737. @item @code{host} (default: @code{"127.0.0.1"})
  26738. The host to bind the server to.
  26739. @item @code{mirror} (default: @code{#f})
  26740. Optional URL of the other Nar Herder instance which should be mirrored.
  26741. This means that this Nar Herder instance will download it's database,
  26742. and keep it up to date.
  26743. @item @code{database} (default: @code{"/var/lib/nar-herder/nar_herder.db"})
  26744. Location for the database. If this Nar Herder instance is mirroring
  26745. another, the database will be downloaded if it doesn't exist. If this
  26746. Nar Herder instance isn't mirroring another, an empty database will be
  26747. created.
  26748. @item @code{database-dump} (default: @code{"/var/lib/nar-herder/nar_herder_dump.db"})
  26749. Location of the database dump. This is created and regularly updated by
  26750. taking a copy of the database. This is the version of the database that
  26751. is available to download.
  26752. @item @code{storage} (default: @code{#f})
  26753. Optional location in which to store nars.
  26754. @item @code{storage-limit} (default: @code{"none"})
  26755. Limit in bytes for the nars stored in the storage location. This can
  26756. also be set to ``none'' so that there is no limit.
  26757. When the storage location exceeds this size, nars are removed according
  26758. to the nar removal criteria.
  26759. @item @code{storage-nar-removal-criteria} (default: @code{'()})
  26760. Criteria used to remove nars from the storage location. These are used
  26761. in conjunction with the storage limit.
  26762. When the storage location exceeds the storage limit size, nars will be
  26763. checked against the nar removal criteria and if any of the criteria
  26764. match, they will be removed. This will continue until the storage
  26765. location is below the storage limit size.
  26766. Each criteria is specified by a string, then an equals sign, then
  26767. another string. Currently, only one criteria is supported, checking if a
  26768. nar is stored on another Nar Herder instance.
  26769. @item @code{ttl} (default: @code{#f})
  26770. Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
  26771. (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
  26772. days, @code{1m} means 1 month, and so on.
  26773. This allows the user's Guix to keep substitute information in cache for
  26774. @var{ttl}.
  26775. @item @code{negative-ttl} (default: @code{#f})
  26776. Similarly produce @code{Cache-Control} HTTP headers to advertise the
  26777. time-to-live (TTL) of @emph{negative} lookups---missing store items, for
  26778. which the HTTP 404 code is returned. By default, no negative TTL is
  26779. advertised.
  26780. @end table
  26781. @end deftp
  26782. @node Linux Services
  26783. @subsection Linux Services
  26784. @cindex oom
  26785. @cindex out of memory killer
  26786. @cindex earlyoom
  26787. @cindex early out of memory daemon
  26788. @subsubheading Early OOM Service
  26789. @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
  26790. Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
  26791. space and provides a more responsive and configurable alternative to the
  26792. in-kernel OOM killer. It is useful to prevent the system from becoming
  26793. unresponsive when it runs out of memory.
  26794. @deffn {Scheme Variable} earlyoom-service-type
  26795. The service type for running @command{earlyoom}, the Early OOM daemon.
  26796. Its value must be a @code{earlyoom-configuration} object, described
  26797. below. The service can be instantiated in its default configuration
  26798. with:
  26799. @lisp
  26800. (service earlyoom-service-type)
  26801. @end lisp
  26802. @end deffn
  26803. @deftp {Data Type} earlyoom-configuration
  26804. This is the configuration record for the @code{earlyoom-service-type}.
  26805. @table @asis
  26806. @item @code{earlyoom} (default: @var{earlyoom})
  26807. The Earlyoom package to use.
  26808. @item @code{minimum-available-memory} (default: @code{10})
  26809. The threshold for the minimum @emph{available} memory, in percentages.
  26810. @item @code{minimum-free-swap} (default: @code{10})
  26811. The threshold for the minimum free swap memory, in percentages.
  26812. @item @code{prefer-regexp} (default: @code{#f})
  26813. A regular expression (as a string) to match the names of the processes
  26814. that should be preferably killed.
  26815. @item @code{avoid-regexp} (default: @code{#f})
  26816. A regular expression (as a string) to match the names of the processes
  26817. that should @emph{not} be killed.
  26818. @item @code{memory-report-interval} (default: @code{0})
  26819. The interval in seconds at which a memory report is printed. It is
  26820. disabled by default.
  26821. @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
  26822. A boolean indicating whether the positive adjustments set in
  26823. @file{/proc/*/oom_score_adj} should be ignored.
  26824. @item @code{show-debug-messages?} (default: @code{#f})
  26825. A boolean indicating whether debug messages should be printed. The logs
  26826. are saved at @file{/var/log/earlyoom.log}.
  26827. @item @code{send-notification-command} (default: @code{#f})
  26828. This can be used to provide a custom command used for sending
  26829. notifications.
  26830. @end table
  26831. @end deftp
  26832. @cindex modprobe
  26833. @cindex kernel module loader
  26834. @subsubheading Kernel Module Loader Service
  26835. The kernel module loader service allows one to load loadable kernel
  26836. modules at boot. This is especially useful for modules that don't
  26837. autoload and need to be manually loaded, as is the case with
  26838. @code{ddcci}.
  26839. @deffn {Scheme Variable} kernel-module-loader-service-type
  26840. The service type for loading loadable kernel modules at boot with
  26841. @command{modprobe}. Its value must be a list of strings representing
  26842. module names. For example loading the drivers provided by
  26843. @code{ddcci-driver-linux}, in debugging mode by passing some module
  26844. parameters, can be done as follow:
  26845. @lisp
  26846. (use-modules (gnu) (gnu services))
  26847. (use-package-modules linux)
  26848. (use-service-modules linux)
  26849. (define ddcci-config
  26850. (plain-file "ddcci.conf"
  26851. "options ddcci dyndbg delay=120"))
  26852. (operating-system
  26853. ...
  26854. (services (cons* (service kernel-module-loader-service-type
  26855. '("ddcci" "ddcci_backlight"))
  26856. (simple-service 'ddcci-config etc-service-type
  26857. (list `("modprobe.d/ddcci.conf"
  26858. ,ddcci-config)))
  26859. %base-services))
  26860. (kernel-loadable-modules (list ddcci-driver-linux)))
  26861. @end lisp
  26862. @end deffn
  26863. @cindex rasdaemon
  26864. @cindex Platform Reliability, Availability and Serviceability daemon
  26865. @subsubheading Rasdaemon Service
  26866. The Rasdaemon service provides a daemon which monitors platform
  26867. @acronym{RAS, Reliability@comma{} Availability@comma{} and Serviceability} reports from
  26868. Linux kernel trace events, logging them to syslogd.
  26869. Reliability, Availability and Serviceability is a concept used on servers meant
  26870. to measure their robustness.
  26871. @strong{Relability} is the probability that a system will produce correct
  26872. outputs:
  26873. @itemize @bullet
  26874. @item Generally measured as Mean Time Between Failures (MTBF), and
  26875. @item Enhanced by features that help to avoid, detect and repair hardware
  26876. faults
  26877. @end itemize
  26878. @strong{Availability} is the probability that a system is operational at a
  26879. given time:
  26880. @itemize @bullet
  26881. @item Generally measured as a percentage of downtime per a period of time, and
  26882. @item Often uses mechanisms to detect and correct hardware faults in runtime.
  26883. @end itemize
  26884. @strong{Serviceability} is the simplicity and speed with which a system can be
  26885. repaired or maintained:
  26886. @itemize @bullet
  26887. @item Generally measured on Mean Time Between Repair (MTBR).
  26888. @end itemize
  26889. Among the monitoring measures, the most usual ones include:
  26890. @itemize @bullet
  26891. @item CPU – detect errors at instruction execution and at L1/L2/L3 caches;
  26892. @item Memory – add error correction logic (ECC) to detect and correct errors;
  26893. @item I/O – add CRC checksums for transferred data;
  26894. @item Storage – RAID, journal file systems, checksums, Self-Monitoring,
  26895. Analysis and Reporting Technology (SMART).
  26896. @end itemize
  26897. By monitoring the number of occurrences of error detections, it is possible to
  26898. identify if the probability of hardware errors is increasing, and, on such
  26899. case, do a preventive maintenance to replace a degraded component while those
  26900. errors are correctable.
  26901. For detailed information about the types of error events gathered and how to
  26902. make sense of them, see the kernel administrator's guide at
  26903. @url{https://www.kernel.org/doc/html/latest/admin-guide/ras.html}.
  26904. @defvr {Scheme Variable} rasdaemon-service-type
  26905. Service type for the @command{rasdaemon} service. It accepts a
  26906. @code{rasdaemon-configuration} object. Instantiating like
  26907. @lisp
  26908. (service rasdaemon-service-type)
  26909. @end lisp
  26910. will load with a default configuration, which monitors all events and logs to
  26911. syslogd.
  26912. @end defvr
  26913. @deftp {Data Type} rasdaemon-configuration
  26914. The data type representing the configuration of @command{rasdaemon}.
  26915. @table @asis
  26916. @item @code{record?} (default: @code{#f})
  26917. A boolean indicating whether to record the events in an SQLite database. This
  26918. provides a more structured access to the information contained in the log file.
  26919. The database location is hard-coded to @file{/var/lib/rasdaemon/ras-mc_event.db}.
  26920. @end table
  26921. @end deftp
  26922. @cindex zram
  26923. @cindex compressed swap
  26924. @cindex Compressed RAM-based block devices
  26925. @subsubheading Zram Device Service
  26926. The Zram device service provides a compressed swap device in system
  26927. memory. The Linux Kernel documentation has more information about
  26928. @uref{https://www.kernel.org/doc/html/latest/admin-guide/blockdev/zram.html,zram}
  26929. devices.
  26930. @deffn {Scheme Variable} zram-device-service-type
  26931. This service creates the zram block device, formats it as swap and
  26932. enables it as a swap device. The service's value is a
  26933. @code{zram-device-configuration} record.
  26934. @deftp {Data Type} zram-device-configuration
  26935. This is the data type representing the configuration for the zram-device
  26936. service.
  26937. @table @asis
  26938. @item @code{size} (default @code{"1G"})
  26939. This is the amount of space you wish to provide for the zram device. It
  26940. accepts a string and can be a number of bytes or use a suffix, eg.:
  26941. @code{"512M"} or @code{1024000}.
  26942. @item @code{compression-algorithm} (default @code{'lzo})
  26943. This is the compression algorithm you wish to use. It is difficult to
  26944. list all the possible compression options, but common ones supported by
  26945. Guix's Linux Libre Kernel include @code{'lzo}, @code{'lz4} and @code{'zstd}.
  26946. @item @code{memory-limit} (default @code{0})
  26947. This is the maximum amount of memory which the zram device can use.
  26948. Setting it to '0' disables the limit. While it is generally expected
  26949. that compression will be 2:1, it is possible that uncompressable data
  26950. can be written to swap and this is a method to limit how much memory can
  26951. be used. It accepts a string and can be a number of bytes or use a
  26952. suffix, eg.: @code{"2G"}.
  26953. @item @code{priority} (default @code{-1})
  26954. This is the priority of the swap device created from the zram device.
  26955. @code{swapon} accepts values between -1 and 32767, with higher values
  26956. indicating higher priority. Higher priority swap will generally be used
  26957. first.
  26958. @end table
  26959. @end deftp
  26960. @end deffn
  26961. @node Hurd Services
  26962. @subsection Hurd Services
  26963. @defvr {Scheme Variable} hurd-console-service-type
  26964. This service starts the fancy @code{VGA} console client on the Hurd.
  26965. The service's value is a @code{hurd-console-configuration} record.
  26966. @end defvr
  26967. @deftp {Data Type} hurd-console-configuration
  26968. This is the data type representing the configuration for the
  26969. hurd-console-service.
  26970. @table @asis
  26971. @item @code{hurd} (default: @var{hurd})
  26972. The Hurd package to use.
  26973. @end table
  26974. @end deftp
  26975. @defvr {Scheme Variable} hurd-getty-service-type
  26976. This service starts a tty using the Hurd @code{getty} program.
  26977. The service's value is a @code{hurd-getty-configuration} record.
  26978. @end defvr
  26979. @deftp {Data Type} hurd-getty-configuration
  26980. This is the data type representing the configuration for the
  26981. hurd-getty-service.
  26982. @table @asis
  26983. @item @code{hurd} (default: @var{hurd})
  26984. The Hurd package to use.
  26985. @item @code{tty}
  26986. The name of the console this Getty runs on---e.g., @code{"tty1"}.
  26987. @item @code{baud-rate} (default: @code{38400})
  26988. An integer specifying the baud rate of the tty.
  26989. @end table
  26990. @end deftp
  26991. @node Miscellaneous Services
  26992. @subsection Miscellaneous Services
  26993. @cindex fingerprint
  26994. @subsubheading Fingerprint Service
  26995. The @code{(gnu services authentication)} module provides a DBus service to
  26996. read and identify fingerprints via a fingerprint sensor.
  26997. @defvr {Scheme Variable} fprintd-service-type
  26998. The service type for @command{fprintd}, which provides the fingerprint
  26999. reading capability.
  27000. @lisp
  27001. (service fprintd-service-type)
  27002. @end lisp
  27003. @end defvr
  27004. @cindex sysctl
  27005. @subsubheading System Control Service
  27006. The @code{(gnu services sysctl)} provides a service to configure kernel
  27007. parameters at boot.
  27008. @defvr {Scheme Variable} sysctl-service-type
  27009. The service type for @command{sysctl}, which modifies kernel parameters
  27010. under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
  27011. instantiated as:
  27012. @lisp
  27013. (service sysctl-service-type
  27014. (sysctl-configuration
  27015. (settings '(("net.ipv4.ip_forward" . "1")))))
  27016. @end lisp
  27017. Since @code{sysctl-service-type} is used in the default lists of
  27018. services, @code{%base-services} and @code{%desktop-services}, you can
  27019. use @code{modify-services} to change its configuration and add the
  27020. kernel parameters that you want (@pxref{Service Reference,
  27021. @code{modify-services}}).
  27022. @lisp
  27023. (modify-services %base-services
  27024. (sysctl-service-type config =>
  27025. (sysctl-configuration
  27026. (settings (append '(("net.ipv4.ip_forward" . "1"))
  27027. %default-sysctl-settings)))))
  27028. @end lisp
  27029. @end defvr
  27030. @deftp {Data Type} sysctl-configuration
  27031. The data type representing the configuration of @command{sysctl}.
  27032. @table @asis
  27033. @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
  27034. The @command{sysctl} executable to use.
  27035. @item @code{settings} (default: @code{%default-sysctl-settings})
  27036. An association list specifies kernel parameters and their values.
  27037. @end table
  27038. @end deftp
  27039. @defvr {Scheme Variable} %default-sysctl-settings
  27040. An association list specifying the default @command{sysctl} parameters
  27041. on Guix System.
  27042. @end defvr
  27043. @cindex pcscd
  27044. @subsubheading PC/SC Smart Card Daemon Service
  27045. The @code{(gnu services security-token)} module provides the following service
  27046. to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
  27047. daemon program for pcsc-lite and the MuscleCard framework. It is a resource
  27048. manager that coordinates communications with smart card readers, smart cards
  27049. and cryptographic tokens that are connected to the system.
  27050. @defvr {Scheme Variable} pcscd-service-type
  27051. Service type for the @command{pcscd} service. Its value must be a
  27052. @code{pcscd-configuration} object. To run pcscd in the default
  27053. configuration, instantiate it as:
  27054. @lisp
  27055. (service pcscd-service-type)
  27056. @end lisp
  27057. @end defvr
  27058. @deftp {Data Type} pcscd-configuration
  27059. The data type representing the configuration of @command{pcscd}.
  27060. @table @asis
  27061. @item @code{pcsc-lite} (default: @code{pcsc-lite})
  27062. The pcsc-lite package that provides pcscd.
  27063. @item @code{usb-drivers} (default: @code{(list ccid)})
  27064. List of packages that provide USB drivers to pcscd. Drivers are expected to be
  27065. under @file{pcsc/drivers} in the store directory of the package.
  27066. @end table
  27067. @end deftp
  27068. @cindex lirc
  27069. @subsubheading Lirc Service
  27070. The @code{(gnu services lirc)} module provides the following service.
  27071. @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
  27072. [#:device #f] [#:driver #f] [#:config-file #f] @
  27073. [#:extra-options '()]
  27074. Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
  27075. decodes infrared signals from remote controls.
  27076. Optionally, @var{device}, @var{driver} and @var{config-file}
  27077. (configuration file name) may be specified. See @command{lircd} manual
  27078. for details.
  27079. Finally, @var{extra-options} is a list of additional command-line options
  27080. passed to @command{lircd}.
  27081. @end deffn
  27082. @cindex spice
  27083. @subsubheading Spice Service
  27084. The @code{(gnu services spice)} module provides the following service.
  27085. @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
  27086. Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
  27087. that enables sharing the clipboard with a vm and setting the guest display
  27088. resolution when the graphical console window resizes.
  27089. @end deffn
  27090. @cindex inputattach
  27091. @subsubheading inputattach Service
  27092. @cindex tablet input, for Xorg
  27093. @cindex touchscreen input, for Xorg
  27094. The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
  27095. use input devices such as Wacom tablets, touchscreens, or joysticks with the
  27096. Xorg display server.
  27097. @deffn {Scheme Variable} inputattach-service-type
  27098. Type of a service that runs @command{inputattach} on a device and
  27099. dispatches events from it.
  27100. @end deffn
  27101. @deftp {Data Type} inputattach-configuration
  27102. @table @asis
  27103. @item @code{device-type} (default: @code{"wacom"})
  27104. The type of device to connect to. Run @command{inputattach --help}, from the
  27105. @code{inputattach} package, to see the list of supported device types.
  27106. @item @code{device} (default: @code{"/dev/ttyS0"})
  27107. The device file to connect to the device.
  27108. @item @code{baud-rate} (default: @code{#f})
  27109. Baud rate to use for the serial connection.
  27110. Should be a number or @code{#f}.
  27111. @item @code{log-file} (default: @code{#f})
  27112. If true, this must be the name of a file to log messages to.
  27113. @end table
  27114. @end deftp
  27115. @subsubheading Dictionary Service
  27116. @cindex dictionary
  27117. The @code{(gnu services dict)} module provides the following service:
  27118. @defvr {Scheme Variable} dicod-service-type
  27119. This is the type of the service that runs the @command{dicod} daemon, an
  27120. implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
  27121. @end defvr
  27122. @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
  27123. Return a service that runs the @command{dicod} daemon, an implementation
  27124. of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
  27125. The optional @var{config} argument specifies the configuration for
  27126. @command{dicod}, which should be a @code{<dicod-configuration>} object, by
  27127. default it serves the GNU Collaborative International Dictionary of English.
  27128. You can add @command{open localhost} to your @file{~/.dico} file to make
  27129. @code{localhost} the default server for @command{dico} client
  27130. (@pxref{Initialization File,,, dico, GNU Dico Manual}).
  27131. @end deffn
  27132. @deftp {Data Type} dicod-configuration
  27133. Data type representing the configuration of dicod.
  27134. @table @asis
  27135. @item @code{dico} (default: @var{dico})
  27136. Package object of the GNU Dico dictionary server.
  27137. @item @code{interfaces} (default: @var{'("localhost")})
  27138. This is the list of IP addresses and ports and possibly socket file
  27139. names to listen to (@pxref{Server Settings, @code{listen} directive,,
  27140. dico, GNU Dico Manual}).
  27141. @item @code{handlers} (default: @var{'()})
  27142. List of @code{<dicod-handler>} objects denoting handlers (module instances).
  27143. @item @code{databases} (default: @var{(list %dicod-database:gcide)})
  27144. List of @code{<dicod-database>} objects denoting dictionaries to be served.
  27145. @end table
  27146. @end deftp
  27147. @deftp {Data Type} dicod-handler
  27148. Data type representing a dictionary handler (module instance).
  27149. @table @asis
  27150. @item @code{name}
  27151. Name of the handler (module instance).
  27152. @item @code{module} (default: @var{#f})
  27153. Name of the dicod module of the handler (instance). If it is @code{#f},
  27154. the module has the same name as the handler.
  27155. (@pxref{Modules,,, dico, GNU Dico Manual}).
  27156. @item @code{options}
  27157. List of strings or gexps representing the arguments for the module handler
  27158. @end table
  27159. @end deftp
  27160. @deftp {Data Type} dicod-database
  27161. Data type representing a dictionary database.
  27162. @table @asis
  27163. @item @code{name}
  27164. Name of the database, will be used in DICT commands.
  27165. @item @code{handler}
  27166. Name of the dicod handler (module instance) used by this database
  27167. (@pxref{Handlers,,, dico, GNU Dico Manual}).
  27168. @item @code{complex?} (default: @var{#f})
  27169. Whether the database configuration complex. The complex configuration
  27170. will need a corresponding @code{<dicod-handler>} object, otherwise not.
  27171. @item @code{options}
  27172. List of strings or gexps representing the arguments for the database
  27173. (@pxref{Databases,,, dico, GNU Dico Manual}).
  27174. @end table
  27175. @end deftp
  27176. @defvr {Scheme Variable} %dicod-database:gcide
  27177. A @code{<dicod-database>} object serving the GNU Collaborative International
  27178. Dictionary of English using the @code{gcide} package.
  27179. @end defvr
  27180. The following is an example @code{dicod-service} configuration.
  27181. @lisp
  27182. (dicod-service #:config
  27183. (dicod-configuration
  27184. (handlers (list (dicod-handler
  27185. (name "wordnet")
  27186. (module "dictorg")
  27187. (options
  27188. (list #~(string-append "dbdir=" #$wordnet))))))
  27189. (databases (list (dicod-database
  27190. (name "wordnet")
  27191. (complex? #t)
  27192. (handler "wordnet")
  27193. (options '("database=wn")))
  27194. %dicod-database:gcide))))
  27195. @end lisp
  27196. @cindex Docker
  27197. @subsubheading Docker Service
  27198. The @code{(gnu services docker)} module provides the following services.
  27199. @defvr {Scheme Variable} docker-service-type
  27200. This is the type of the service that runs @url{https://www.docker.com,Docker},
  27201. a daemon that can execute application bundles (sometimes referred to as
  27202. ``containers'') in isolated environments.
  27203. @end defvr
  27204. @deftp {Data Type} docker-configuration
  27205. This is the data type representing the configuration of Docker and Containerd.
  27206. @table @asis
  27207. @item @code{docker} (default: @code{docker})
  27208. The Docker daemon package to use.
  27209. @item @code{docker-cli} (default: @code{docker-cli})
  27210. The Docker client package to use.
  27211. @item @code{containerd} (default: @var{containerd})
  27212. The Containerd package to use.
  27213. @item @code{proxy} (default @var{docker-libnetwork-cmd-proxy})
  27214. The Docker user-land networking proxy package to use.
  27215. @item @code{enable-proxy?} (default @code{#t})
  27216. Enable or disable the use of the Docker user-land networking proxy.
  27217. @item @code{debug?} (default @code{#f})
  27218. Enable or disable debug output.
  27219. @item @code{enable-iptables?} (default @code{#t})
  27220. Enable or disable the addition of iptables rules.
  27221. @item @code{environment-variables} (default: @code{()})
  27222. List of environment variables to set for @command{dockerd}.
  27223. This must be a list of strings where each string has the form
  27224. @samp{@var{key}=@var{value}} as in this example:
  27225. @lisp
  27226. (list "LANGUAGE=eo:ca:eu"
  27227. "TMPDIR=/tmp/dockerd")
  27228. @end lisp
  27229. @end table
  27230. @end deftp
  27231. @cindex Singularity, container service
  27232. @defvr {Scheme Variable} singularity-service-type
  27233. This is the type of the service that allows you to run
  27234. @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
  27235. create and run application bundles (aka. ``containers''). The value for this
  27236. service is the Singularity package to use.
  27237. The service does not install a daemon; instead, it installs helper programs as
  27238. setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
  27239. @command{singularity run} and similar commands.
  27240. @end defvr
  27241. @cindex Audit
  27242. @subsubheading Auditd Service
  27243. The @code{(gnu services auditd)} module provides the following service.
  27244. @defvr {Scheme Variable} auditd-service-type
  27245. This is the type of the service that runs
  27246. @url{https://people.redhat.com/sgrubb/audit/,auditd},
  27247. a daemon that tracks security-relevant information on your system.
  27248. Examples of things that can be tracked:
  27249. @enumerate
  27250. @item
  27251. File accesses
  27252. @item
  27253. System calls
  27254. @item
  27255. Invoked commands
  27256. @item
  27257. Failed login attempts
  27258. @item
  27259. Firewall filtering
  27260. @item
  27261. Network access
  27262. @end enumerate
  27263. @command{auditctl} from the @code{audit} package can be used in order
  27264. to add or remove events to be tracked (until the next reboot).
  27265. In order to permanently track events, put the command line arguments
  27266. of auditctl into a file called @code{audit.rules} in the configuration
  27267. directory (see below).
  27268. @command{aureport} from the @code{audit} package can be used in order
  27269. to view a report of all recorded events.
  27270. The audit daemon by default logs into the file
  27271. @file{/var/log/audit.log}.
  27272. @end defvr
  27273. @deftp {Data Type} auditd-configuration
  27274. This is the data type representing the configuration of auditd.
  27275. @table @asis
  27276. @item @code{audit} (default: @code{audit})
  27277. The audit package to use.
  27278. @item @code{configuration-directory} (default: @code{%default-auditd-configuration-directory})
  27279. The directory containing the configuration file for the audit package, which
  27280. must be named @code{auditd.conf}, and optionally some audit rules to
  27281. instantiate on startup.
  27282. @end table
  27283. @end deftp
  27284. @cindex rshiny
  27285. @subsubheading R-Shiny service
  27286. The @code{(gnu services science)} module provides the following service.
  27287. @defvr {Scheme Variable} rshiny-service-type
  27288. This is a type of service which is used to run a webapp created with
  27289. @code{r-shiny}. This service sets the @env{R_LIBS_USER} environment
  27290. variable and runs the provided script to call @code{runApp}.
  27291. @deftp {Data Type} rshiny-configuration
  27292. This is the data type representing the configuration of rshiny.
  27293. @table @asis
  27294. @item @code{package} (default: @code{r-shiny})
  27295. The package to use.
  27296. @item @code{binary} (defaunlt @code{"rshiny"})
  27297. The name of the binary or shell script located at @code{package/bin/} to
  27298. run when the service is run.
  27299. The common way to create this file is as follows:
  27300. @lisp
  27301. @dots{}
  27302. (let* ((out (assoc-ref %outputs "out"))
  27303. (targetdir (string-append out "/share/" ,name))
  27304. (app (string-append out "/bin/" ,name))
  27305. (Rbin (search-input-file %build-inputs "/bin/Rscript")))
  27306. ;; @dots{}
  27307. (mkdir-p (string-append out "/bin"))
  27308. (call-with-output-file app
  27309. (lambda (port)
  27310. (format port
  27311. "#!~a
  27312. library(shiny)
  27313. setwd(\"~a\")
  27314. runApp(launch.browser=0, port=4202)~%\n"
  27315. Rbin targetdir))))
  27316. @end lisp
  27317. @end table
  27318. @end deftp
  27319. @end defvr
  27320. @cindex Nix
  27321. @subsubheading Nix service
  27322. The @code{(gnu services nix)} module provides the following service.
  27323. @defvr {Scheme Variable} nix-service-type
  27324. This is the type of the service that runs build daemon of the
  27325. @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
  27326. how to use it:
  27327. @lisp
  27328. (use-modules (gnu))
  27329. (use-service-modules nix)
  27330. (use-package-modules package-management)
  27331. (operating-system
  27332. ;; @dots{}
  27333. (packages (append (list nix)
  27334. %base-packages))
  27335. (services (append (list (service nix-service-type))
  27336. %base-services)))
  27337. @end lisp
  27338. After @command{guix system reconfigure} configure Nix for your user:
  27339. @itemize
  27340. @item Add a Nix channel and update it. See
  27341. @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
  27342. @item Create a symlink to your profile and activate Nix profile:
  27343. @end itemize
  27344. @example
  27345. $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
  27346. $ source /run/current-system/profile/etc/profile.d/nix.sh
  27347. @end example
  27348. @end defvr
  27349. @deftp {Data Type} nix-configuration
  27350. This data type represents the configuration of the Nix daemon.
  27351. @table @asis
  27352. @item @code{nix} (default: @code{nix})
  27353. The Nix package to use.
  27354. @item @code{sandbox} (default: @code{#t})
  27355. Specifies whether builds are sandboxed by default.
  27356. @item @code{build-sandbox-items} (default: @code{'()})
  27357. This is a list of strings or objects appended to the
  27358. @code{build-sandbox-items} field of the configuration file.
  27359. @item @code{extra-config} (default: @code{'()})
  27360. This is a list of strings or objects appended to the configuration file.
  27361. It is used to pass extra text to be added verbatim to the configuration
  27362. file.
  27363. @item @code{extra-options} (default: @code{'()})
  27364. Extra command line options for @code{nix-service-type}.
  27365. @end table
  27366. @end deftp
  27367. @node Setuid Programs
  27368. @section Setuid Programs
  27369. @cindex setuid programs
  27370. Some programs need to run with ``root'' privileges, even when they are
  27371. launched by unprivileged users. A notorious example is the
  27372. @command{passwd} program, which users can run to change their
  27373. password, and which needs to access the @file{/etc/passwd} and
  27374. @file{/etc/shadow} files---something normally restricted to root, for
  27375. obvious security reasons. To address that, these executables are
  27376. @dfn{setuid-root}, meaning that they always run with root privileges
  27377. (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
  27378. for more info about the setuid mechanism).
  27379. The store itself @emph{cannot} contain setuid programs: that would be a
  27380. security issue since any user on the system can write derivations that
  27381. populate the store (@pxref{The Store}). Thus, a different mechanism is
  27382. used: instead of changing the setuid bit directly on files that are in
  27383. the store, we let the system administrator @emph{declare} which programs
  27384. should be setuid root.
  27385. The @code{setuid-programs} field of an @code{operating-system}
  27386. declaration contains a list of @code{<setuid-program>} denoting the
  27387. names of programs to have a setuid or setgid bit set (@pxref{Using the
  27388. Configuration System}). For instance, the @command{mount.nfs} program,
  27389. which is part of the nfs-utils package, with a setuid root can be
  27390. designated like this:
  27391. @lisp
  27392. (setuid-program
  27393. (program (file-append nfs-utils "/sbin/mount.nfs")))
  27394. @end lisp
  27395. And then, to make @command{mount.nfs} setuid on your system, add the
  27396. previous example to your operating system declaration by appending it to
  27397. @code{%setuid-programs} like this:
  27398. @lisp
  27399. (operating-system
  27400. ;; Some fields omitted...
  27401. (setuid-programs
  27402. (append (list (setuid-program
  27403. (program (file-append nfs-utils "/sbin/mount.nfs"))))
  27404. %setuid-programs)))
  27405. @end lisp
  27406. @deftp {Data Type} setuid-program
  27407. This data type represents a program with a setuid or setgid bit set.
  27408. @table @asis
  27409. @item @code{program}
  27410. A file-like object having its setuid and/or setgid bit set.
  27411. @item @code{setuid?} (default: @code{#t})
  27412. Whether to set user setuid bit.
  27413. @item @code{setgid?} (default: @code{#f})
  27414. Whether to set group setgid bit.
  27415. @item @code{user} (default: @code{0})
  27416. UID (integer) or user name (string) for the user owner of the program,
  27417. defaults to root.
  27418. @item @code{group} (default: @code{0})
  27419. GID (integer) goup name (string) for the group owner of the program,
  27420. defaults to root.
  27421. @end table
  27422. @end deftp
  27423. A default set of setuid programs is defined by the
  27424. @code{%setuid-programs} variable of the @code{(gnu system)} module.
  27425. @defvr {Scheme Variable} %setuid-programs
  27426. A list of @code{<setuid-program>} denoting common programs that are
  27427. setuid-root.
  27428. The list includes commands such as @command{passwd}, @command{ping},
  27429. @command{su}, and @command{sudo}.
  27430. @end defvr
  27431. Under the hood, the actual setuid programs are created in the
  27432. @file{/run/setuid-programs} directory at system activation time. The
  27433. files in this directory refer to the ``real'' binaries, which are in the
  27434. store.
  27435. @node X.509 Certificates
  27436. @section X.509 Certificates
  27437. @cindex HTTPS, certificates
  27438. @cindex X.509 certificates
  27439. @cindex TLS
  27440. Web servers available over HTTPS (that is, HTTP over the transport-layer
  27441. security mechanism, TLS) send client programs an @dfn{X.509 certificate}
  27442. that the client can then use to @emph{authenticate} the server. To do
  27443. that, clients verify that the server's certificate is signed by a
  27444. so-called @dfn{certificate authority} (CA). But to verify the CA's
  27445. signature, clients must have first acquired the CA's certificate.
  27446. Web browsers such as GNU@tie{}IceCat include their own set of CA
  27447. certificates, such that they are able to verify CA signatures
  27448. out-of-the-box.
  27449. However, most other programs that can talk HTTPS---@command{wget},
  27450. @command{git}, @command{w3m}, etc.---need to be told where CA
  27451. certificates can be found.
  27452. @cindex @code{nss-certs}
  27453. In Guix, this is done by adding a package that provides certificates
  27454. to the @code{packages} field of the @code{operating-system} declaration
  27455. (@pxref{operating-system Reference}). Guix includes one such package,
  27456. @code{nss-certs}, which is a set of CA certificates provided as part of
  27457. Mozilla's Network Security Services.
  27458. Note that it is @emph{not} part of @code{%base-packages}, so you need to
  27459. explicitly add it. The @file{/etc/ssl/certs} directory, which is where
  27460. most applications and libraries look for certificates by default, points
  27461. to the certificates installed globally.
  27462. Unprivileged users, including users of Guix on a foreign distro,
  27463. can also install their own certificate package in
  27464. their profile. A number of environment variables need to be defined so
  27465. that applications and libraries know where to find them. Namely, the
  27466. OpenSSL library honors the @env{SSL_CERT_DIR} and @env{SSL_CERT_FILE}
  27467. variables. Some applications add their own environment variables; for
  27468. instance, the Git version control system honors the certificate bundle
  27469. pointed to by the @env{GIT_SSL_CAINFO} environment variable. Thus, you
  27470. would typically run something like:
  27471. @example
  27472. guix install nss-certs
  27473. export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
  27474. export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
  27475. export GIT_SSL_CAINFO="$SSL_CERT_FILE"
  27476. @end example
  27477. As another example, R requires the @env{CURL_CA_BUNDLE} environment
  27478. variable to point to a certificate bundle, so you would have to run
  27479. something like this:
  27480. @example
  27481. guix install nss-certs
  27482. export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
  27483. @end example
  27484. For other applications you may want to look up the required environment
  27485. variable in the relevant documentation.
  27486. @node Name Service Switch
  27487. @section Name Service Switch
  27488. @cindex name service switch
  27489. @cindex NSS
  27490. The @code{(gnu system nss)} module provides bindings to the
  27491. configuration file of the libc @dfn{name service switch} or @dfn{NSS}
  27492. (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
  27493. Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
  27494. extended with new ``name'' lookup methods for system databases, which
  27495. includes host names, service names, user accounts, and more (@pxref{Name
  27496. Service Switch, System Databases and Name Service Switch,, libc, The GNU
  27497. C Library Reference Manual}).
  27498. The NSS configuration specifies, for each system database, which lookup
  27499. method is to be used, and how the various methods are chained
  27500. together---for instance, under which circumstances NSS should try the
  27501. next method in the list. The NSS configuration is given in the
  27502. @code{name-service-switch} field of @code{operating-system} declarations
  27503. (@pxref{operating-system Reference, @code{name-service-switch}}).
  27504. @cindex nss-mdns
  27505. @cindex .local, host name lookup
  27506. As an example, the declaration below configures the NSS to use the
  27507. @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
  27508. back-end}, which supports host name lookups over multicast DNS (mDNS)
  27509. for host names ending in @code{.local}:
  27510. @lisp
  27511. (name-service-switch
  27512. (hosts (list %files ;first, check /etc/hosts
  27513. ;; If the above did not succeed, try
  27514. ;; with 'mdns_minimal'.
  27515. (name-service
  27516. (name "mdns_minimal")
  27517. ;; 'mdns_minimal' is authoritative for
  27518. ;; '.local'. When it returns "not found",
  27519. ;; no need to try the next methods.
  27520. (reaction (lookup-specification
  27521. (not-found => return))))
  27522. ;; Then fall back to DNS.
  27523. (name-service
  27524. (name "dns"))
  27525. ;; Finally, try with the "full" 'mdns'.
  27526. (name-service
  27527. (name "mdns")))))
  27528. @end lisp
  27529. Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
  27530. contains this configuration, so you will not have to type it if all you
  27531. want is to have @code{.local} host lookup working.
  27532. Note that, in this case, in addition to setting the
  27533. @code{name-service-switch} of the @code{operating-system} declaration,
  27534. you also need to use @code{avahi-service-type} (@pxref{Networking Services,
  27535. @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
  27536. (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
  27537. to the name service cache daemon (@pxref{Base Services,
  27538. @code{nscd-service}}).
  27539. For convenience, the following variables provide typical NSS
  27540. configurations.
  27541. @defvr {Scheme Variable} %default-nss
  27542. This is the default name service switch configuration, a
  27543. @code{name-service-switch} object.
  27544. @end defvr
  27545. @defvr {Scheme Variable} %mdns-host-lookup-nss
  27546. This is the name service switch configuration with support for host name
  27547. lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
  27548. @end defvr
  27549. The reference for name service switch configuration is given below. It
  27550. is a direct mapping of the configuration file format of the C library , so
  27551. please refer to the C library manual for more information (@pxref{NSS
  27552. Configuration File,,, libc, The GNU C Library Reference Manual}).
  27553. Compared to the configuration file format of libc NSS, it has the advantage
  27554. not only of adding this warm parenthetic feel that we like, but also
  27555. static checks: you will know about syntax errors and typos as soon as you
  27556. run @command{guix system}.
  27557. @deftp {Data Type} name-service-switch
  27558. This is the data type representation the configuration of libc's name
  27559. service switch (NSS). Each field below represents one of the supported
  27560. system databases.
  27561. @table @code
  27562. @item aliases
  27563. @itemx ethers
  27564. @itemx group
  27565. @itemx gshadow
  27566. @itemx hosts
  27567. @itemx initgroups
  27568. @itemx netgroup
  27569. @itemx networks
  27570. @itemx password
  27571. @itemx public-key
  27572. @itemx rpc
  27573. @itemx services
  27574. @itemx shadow
  27575. The system databases handled by the NSS@. Each of these fields must be a
  27576. list of @code{<name-service>} objects (see below).
  27577. @end table
  27578. @end deftp
  27579. @deftp {Data Type} name-service
  27580. This is the data type representing an actual name service and the
  27581. associated lookup action.
  27582. @table @code
  27583. @item name
  27584. A string denoting the name service (@pxref{Services in the NSS
  27585. configuration,,, libc, The GNU C Library Reference Manual}).
  27586. Note that name services listed here must be visible to nscd. This is
  27587. achieved by passing the @code{#:name-services} argument to
  27588. @code{nscd-service} the list of packages providing the needed name
  27589. services (@pxref{Base Services, @code{nscd-service}}).
  27590. @item reaction
  27591. An action specified using the @code{lookup-specification} macro
  27592. (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
  27593. Reference Manual}). For example:
  27594. @lisp
  27595. (lookup-specification (unavailable => continue)
  27596. (success => return))
  27597. @end lisp
  27598. @end table
  27599. @end deftp
  27600. @node Initial RAM Disk
  27601. @section Initial RAM Disk
  27602. @cindex initrd
  27603. @cindex initial RAM disk
  27604. For bootstrapping purposes, the Linux-Libre kernel is passed an
  27605. @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
  27606. root file system as well as an initialization script. The latter is
  27607. responsible for mounting the real root file system, and for loading any
  27608. kernel modules that may be needed to achieve that.
  27609. The @code{initrd-modules} field of an @code{operating-system}
  27610. declaration allows you to specify Linux-libre kernel modules that must
  27611. be available in the initrd. In particular, this is where you would list
  27612. modules needed to actually drive the hard disk where your root partition
  27613. is---although the default value of @code{initrd-modules} should cover
  27614. most use cases. For example, assuming you need the @code{megaraid_sas}
  27615. module in addition to the default modules to be able to access your root
  27616. file system, you would write:
  27617. @lisp
  27618. (operating-system
  27619. ;; @dots{}
  27620. (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
  27621. @end lisp
  27622. @defvr {Scheme Variable} %base-initrd-modules
  27623. This is the list of kernel modules included in the initrd by default.
  27624. @end defvr
  27625. Furthermore, if you need lower-level customization, the @code{initrd}
  27626. field of an @code{operating-system} declaration allows
  27627. you to specify which initrd you would like to use. The @code{(gnu
  27628. system linux-initrd)} module provides three ways to build an initrd: the
  27629. high-level @code{base-initrd} procedure and the low-level
  27630. @code{raw-initrd} and @code{expression->initrd} procedures.
  27631. The @code{base-initrd} procedure is intended to cover most common uses.
  27632. For example, if you want to add a bunch of kernel modules to be loaded
  27633. at boot time, you can define the @code{initrd} field of the operating
  27634. system declaration like this:
  27635. @lisp
  27636. (initrd (lambda (file-systems . rest)
  27637. ;; Create a standard initrd but set up networking
  27638. ;; with the parameters QEMU expects by default.
  27639. (apply base-initrd file-systems
  27640. #:qemu-networking? #t
  27641. rest)))
  27642. @end lisp
  27643. The @code{base-initrd} procedure also handles common use cases that
  27644. involves using the system as a QEMU guest, or as a ``live'' system with
  27645. volatile root file system.
  27646. The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
  27647. Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
  27648. such as trying to guess which kernel modules and packages should be included
  27649. to the initrd. An example use of @code{raw-initrd} is when a user has
  27650. a custom Linux kernel configuration and default kernel modules included by
  27651. @code{base-initrd} are not available.
  27652. The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
  27653. honors several options passed on the Linux kernel command line
  27654. (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
  27655. @code{-append} option of QEMU), notably:
  27656. @table @code
  27657. @item gnu.load=@var{boot}
  27658. Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
  27659. program, once it has mounted the root file system.
  27660. Guix uses this option to yield control to a boot program that runs the
  27661. service activation programs and then spawns the GNU@tie{}Shepherd, the
  27662. initialization system.
  27663. @item root=@var{root}
  27664. Mount @var{root} as the root file system. @var{root} can be a device
  27665. name like @code{/dev/sda1}, a file system label, or a file system UUID.
  27666. When unspecified, the device name from the root file system of the
  27667. operating system declaration is used.
  27668. @item rootfstype=@var{type}
  27669. Set the type of the root file system. It overrides the @code{type}
  27670. field of the root file system specified via the @code{operating-system}
  27671. declaration, if any.
  27672. @item rootflags=@var{options}
  27673. Set the mount @emph{options} of the root file system. It overrides the
  27674. @code{options} field of the root file system specified via the
  27675. @code{operating-system} declaration, if any.
  27676. @item fsck.mode=@var{mode}
  27677. Whether to check the @var{root} file system for errors before mounting
  27678. it. @var{mode} is one of @code{skip} (never check), @code{force} (always
  27679. check), or @code{auto} to respect the root file-system object's 'check?'
  27680. setting (@pxref{File Systems}) and run a full scan only if the file system
  27681. was not cleanly shut down.
  27682. @code{auto} is the default if this option is not present or if @var{mode}
  27683. is not one of the above.
  27684. @item fsck.repair=@var{level}
  27685. The level of repairs to perform automatically if errors are found in the
  27686. @var{root} file system. @var{level} is one of @code{no} (do not write to
  27687. @var{root} at all if possible), @code{yes} (repair as much as possible),
  27688. or @code{preen} to repair problems considered safe to repair automatically.
  27689. @code{preen} is the default if this option is not present or if @var{level}
  27690. is not one of the above.
  27691. @item gnu.system=@var{system}
  27692. Have @file{/run/booted-system} and @file{/run/current-system} point to
  27693. @var{system}.
  27694. @item modprobe.blacklist=@var{modules}@dots{}
  27695. @cindex module, black-listing
  27696. @cindex black list, of kernel modules
  27697. Instruct the initial RAM disk as well as the @command{modprobe} command
  27698. (from the kmod package) to refuse to load @var{modules}. @var{modules}
  27699. must be a comma-separated list of module names---e.g.,
  27700. @code{usbkbd,9pnet}.
  27701. @item gnu.repl
  27702. Start a read-eval-print loop (REPL) from the initial RAM disk before it
  27703. tries to load kernel modules and to mount the root file system. Our
  27704. marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
  27705. love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
  27706. Manual}, for more information on Guile's REPL.
  27707. @end table
  27708. Now that you know all the features that initial RAM disks produced by
  27709. @code{base-initrd} and @code{raw-initrd} provide,
  27710. here is how to use it and customize it further.
  27711. @cindex initrd
  27712. @cindex initial RAM disk
  27713. @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
  27714. [#:linux-modules '()] [#:mapped-devices '()] @
  27715. [#:keyboard-layout #f] @
  27716. [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
  27717. Return a derivation that builds a raw initrd. @var{file-systems} is
  27718. a list of file systems to be mounted by the initrd, possibly in addition to
  27719. the root file system specified on the kernel command line via @option{root}.
  27720. @var{linux-modules} is a list of kernel modules to be loaded at boot time.
  27721. @var{mapped-devices} is a list of device mappings to realize before
  27722. @var{file-systems} are mounted (@pxref{Mapped Devices}).
  27723. @var{helper-packages} is a list of packages to be copied in the initrd.
  27724. It may
  27725. include @code{e2fsck/static} or other packages needed by the initrd to check
  27726. the root file system.
  27727. When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
  27728. the desired console keyboard layout. This is done before @var{mapped-devices}
  27729. are set up and before @var{file-systems} are mounted such that, should the
  27730. user need to enter a passphrase or use the REPL, this happens using the
  27731. intended keyboard layout.
  27732. When @var{qemu-networking?} is true, set up networking with the standard QEMU
  27733. parameters. When @var{virtio?} is true, load additional modules so that the
  27734. initrd can be used as a QEMU guest with para-virtualized I/O drivers.
  27735. When @var{volatile-root?} is true, the root file system is writable but any changes
  27736. to it are lost.
  27737. @end deffn
  27738. @deffn {Scheme Procedure} base-initrd @var{file-systems} @
  27739. [#:mapped-devices '()] [#:keyboard-layout #f] @
  27740. [#:qemu-networking? #f] [#:volatile-root? #f] @
  27741. [#:linux-modules '()]
  27742. Return as a file-like object a generic initrd, with kernel
  27743. modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
  27744. mounted by the initrd, possibly in addition to the root file system specified
  27745. on the kernel command line via @option{root}. @var{mapped-devices} is a list of device
  27746. mappings to realize before @var{file-systems} are mounted.
  27747. When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
  27748. the desired console keyboard layout. This is done before @var{mapped-devices}
  27749. are set up and before @var{file-systems} are mounted such that, should the
  27750. user need to enter a passphrase or use the REPL, this happens using the
  27751. intended keyboard layout.
  27752. @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
  27753. The initrd is automatically populated with all the kernel modules necessary
  27754. for @var{file-systems} and for the given options. Additional kernel
  27755. modules can be listed in @var{linux-modules}. They will be added to the initrd, and
  27756. loaded at boot time in the order in which they appear.
  27757. @end deffn
  27758. Needless to say, the initrds we produce and use embed a
  27759. statically-linked Guile, and the initialization program is a Guile
  27760. program. That gives a lot of flexibility. The
  27761. @code{expression->initrd} procedure builds such an initrd, given the
  27762. program to run in that initrd.
  27763. @deffn {Scheme Procedure} expression->initrd @var{exp} @
  27764. [#:guile %guile-static-stripped] [#:name "guile-initrd"]
  27765. Return as a file-like object a Linux initrd (a gzipped cpio archive)
  27766. containing @var{guile} and that evaluates @var{exp}, a G-expression,
  27767. upon booting. All the derivations referenced by @var{exp} are
  27768. automatically copied to the initrd.
  27769. @end deffn
  27770. @node Bootloader Configuration
  27771. @section Bootloader Configuration
  27772. @cindex bootloader
  27773. @cindex boot loader
  27774. The operating system supports multiple bootloaders. The bootloader is
  27775. configured using @code{bootloader-configuration} declaration. All the
  27776. fields of this structure are bootloader agnostic except for one field,
  27777. @code{bootloader} that indicates the bootloader to be configured and
  27778. installed.
  27779. Some of the bootloaders do not honor every field of
  27780. @code{bootloader-configuration}. For instance, the extlinux
  27781. bootloader does not support themes and thus ignores the @code{theme}
  27782. field.
  27783. @deftp {Data Type} bootloader-configuration
  27784. The type of a bootloader configuration declaration.
  27785. @table @asis
  27786. @item @code{bootloader}
  27787. @cindex EFI, bootloader
  27788. @cindex UEFI, bootloader
  27789. @cindex BIOS, bootloader
  27790. The bootloader to use, as a @code{bootloader} object. For now
  27791. @code{grub-bootloader}, @code{grub-efi-bootloader},
  27792. @code{grub-efi-netboot-bootloader}, @code{extlinux-bootloader} and
  27793. @code{u-boot-bootloader} are supported.
  27794. @cindex ARM, bootloaders
  27795. @cindex AArch64, bootloaders
  27796. Available bootloaders are described in @code{(gnu bootloader @dots{})}
  27797. modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
  27798. of bootloaders for a wide range of ARM and AArch64 systems, using the
  27799. @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
  27800. @vindex grub-efi-bootloader
  27801. @code{grub-efi-bootloader} allows to boot on modern systems using the
  27802. @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
  27803. use if the installation image contains a @file{/sys/firmware/efi} directory
  27804. when you boot it on your system.
  27805. @vindex grub-bootloader
  27806. @code{grub-bootloader} allows you to boot in particular Intel-based machines
  27807. in ``legacy'' BIOS mode.
  27808. @vindex grub-efi-netboot-bootloader
  27809. @code{grub-efi-netboot-bootloader} allows you to boot your system over network
  27810. through TFTP@. In combination with an NFS root file system this allows you to
  27811. build a diskless Guix system.
  27812. The installation of the @code{grub-efi-netboot-bootloader} generates the
  27813. content of the TFTP root directory at @code{targets} (@pxref{Bootloader
  27814. Configuration, @code{targets}}), to be served by a TFTP server. You may
  27815. want to mount your TFTP server directories onto the @code{targets} to
  27816. move the required files to the TFTP server automatically.
  27817. If you plan to use an NFS root file system as well (actually if you mount the
  27818. store from an NFS share), then the TFTP server needs to serve the file
  27819. @file{/boot/grub/grub.cfg} and other files from the store (like GRUBs background
  27820. image, the kernel (@pxref{operating-system Reference, @code{kernel}}) and the
  27821. initrd (@pxref{operating-system Reference, @code{initrd}})), too. All these
  27822. files from the store will be accessed by GRUB through TFTP with their normal
  27823. store path, for example as
  27824. @file{tftp://tftp-server/gnu/store/…-initrd/initrd.cpio.gz}.
  27825. Two symlinks are created to make this possible. For each target in the
  27826. @code{targets} field, the first symlink is
  27827. @samp{target}@file{/efi/Guix/boot/grub/grub.cfg} pointing to
  27828. @file{../../../boot/grub/grub.cfg}, where @samp{target} may be
  27829. @file{/boot}. In this case the link is not leaving the served TFTP root
  27830. directory, but otherwise it does. The second link is
  27831. @samp{target}@file{/gnu/store} and points to @file{../gnu/store}. This
  27832. link is leaving the served TFTP root directory.
  27833. The assumption behind all this is that you have an NFS server exporting
  27834. the root file system for your Guix system, and additionally a TFTP
  27835. server exporting your @code{targets} directories—usually a single
  27836. @file{/boot}—from that same root file system for your Guix system. In
  27837. this constellation the symlinks will work.
  27838. For other constellations you will have to program your own bootloader
  27839. installer, which then takes care to make necessary files from the store
  27840. accessible through TFTP, for example by copying them into the TFTP root
  27841. directory to your @code{targets}.
  27842. It is important to note that symlinks pointing outside the TFTP root directory
  27843. may need to be allowed in the configuration of your TFTP server. Further the
  27844. store link exposes the whole store through TFTP@. Both points need to be
  27845. considered carefully for security aspects.
  27846. Beside the @code{grub-efi-netboot-bootloader}, the already mentioned TFTP and
  27847. NFS servers, you also need a properly configured DHCP server to make the booting
  27848. over netboot possible. For all this we can currently only recommend you to look
  27849. for instructions about @acronym{PXE, Preboot eXecution Environment}.
  27850. @item @code{targets}
  27851. This is a list of strings denoting the targets onto which to install the
  27852. bootloader.
  27853. The interpretation of targets depends on the bootloader in question.
  27854. For @code{grub-bootloader}, for example, they should be device names
  27855. understood by the bootloader @command{installer} command, such as
  27856. @code{/dev/sda} or @code{(hd0)} (@pxref{Invoking grub-install,,, grub,
  27857. GNU GRUB Manual}). For @code{grub-efi-bootloader}, they should be mount
  27858. points of the EFI file system, usually @file{/boot/efi}. For
  27859. @code{grub-efi-netboot-bootloader}, @code{targets} should be the mount
  27860. points corresponding to TFTP root directories served by your TFTP
  27861. server.
  27862. @item @code{menu-entries} (default: @code{()})
  27863. A possibly empty list of @code{menu-entry} objects (see below), denoting
  27864. entries to appear in the bootloader menu, in addition to the current
  27865. system entry and the entry pointing to previous system generations.
  27866. @item @code{default-entry} (default: @code{0})
  27867. The index of the default boot menu entry. Index 0 is for the entry of the
  27868. current system.
  27869. @item @code{timeout} (default: @code{5})
  27870. The number of seconds to wait for keyboard input before booting. Set to
  27871. 0 to boot immediately, and to -1 to wait indefinitely.
  27872. @cindex keyboard layout, for the bootloader
  27873. @item @code{keyboard-layout} (default: @code{#f})
  27874. If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
  27875. layout, usually US@tie{}English (``qwerty'').
  27876. Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
  27877. Layout}).
  27878. @quotation Note
  27879. This option is currently ignored by bootloaders other than @code{grub} and
  27880. @code{grub-efi}.
  27881. @end quotation
  27882. @item @code{theme} (default: @var{#f})
  27883. The bootloader theme object describing the theme to use. If no theme
  27884. is provided, some bootloaders might use a default theme, that's true
  27885. for GRUB.
  27886. @item @code{terminal-outputs} (default: @code{'(gfxterm)})
  27887. The output terminals used for the bootloader boot menu, as a list of
  27888. symbols. GRUB accepts the values: @code{console}, @code{serial},
  27889. @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
  27890. @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
  27891. corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
  27892. configuration,,, grub,GNU GRUB manual}).
  27893. @item @code{terminal-inputs} (default: @code{'()})
  27894. The input terminals used for the bootloader boot menu, as a list of
  27895. symbols. For GRUB, the default is the native platform terminal as
  27896. determined at run-time. GRUB accepts the values: @code{console},
  27897. @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
  27898. @code{usb_keyboard}. This field corresponds to the GRUB variable
  27899. @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
  27900. manual}).
  27901. @item @code{serial-unit} (default: @code{#f})
  27902. The serial unit used by the bootloader, as an integer from 0 to 3.
  27903. For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
  27904. corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
  27905. @item @code{serial-speed} (default: @code{#f})
  27906. The speed of the serial interface, as an integer. For GRUB, the
  27907. default value is chosen at run-time; currently GRUB chooses
  27908. 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
  27909. @end table
  27910. @end deftp
  27911. @cindex dual boot
  27912. @cindex boot menu
  27913. Should you want to list additional boot menu entries @i{via} the
  27914. @code{menu-entries} field above, you will need to create them with the
  27915. @code{menu-entry} form. For example, imagine you want to be able to
  27916. boot another distro (hard to imagine!), you can define a menu entry
  27917. along these lines:
  27918. @lisp
  27919. (menu-entry
  27920. (label "The Other Distro")
  27921. (linux "/boot/old/vmlinux-2.6.32")
  27922. (linux-arguments '("root=/dev/sda2"))
  27923. (initrd "/boot/old/initrd"))
  27924. @end lisp
  27925. Details below.
  27926. @deftp {Data Type} menu-entry
  27927. The type of an entry in the bootloader menu.
  27928. @table @asis
  27929. @item @code{label}
  27930. The label to show in the menu---e.g., @code{"GNU"}.
  27931. @item @code{linux} (default: @code{#f})
  27932. The Linux kernel image to boot, for example:
  27933. @lisp
  27934. (file-append linux-libre "/bzImage")
  27935. @end lisp
  27936. For GRUB, it is also possible to specify a device explicitly in the
  27937. file path using GRUB's device naming convention (@pxref{Naming
  27938. convention,,, grub, GNU GRUB manual}), for example:
  27939. @example
  27940. "(hd0,msdos1)/boot/vmlinuz"
  27941. @end example
  27942. If the device is specified explicitly as above, then the @code{device}
  27943. field is ignored entirely.
  27944. @item @code{linux-arguments} (default: @code{()})
  27945. The list of extra Linux kernel command-line arguments---e.g.,
  27946. @code{("console=ttyS0")}.
  27947. @item @code{initrd} (default: @code{#f})
  27948. A G-Expression or string denoting the file name of the initial RAM disk
  27949. to use (@pxref{G-Expressions}).
  27950. @item @code{device} (default: @code{#f})
  27951. The device where the kernel and initrd are to be found---i.e., for GRUB,
  27952. @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
  27953. This may be a file system label (a string), a file system UUID (a
  27954. bytevector, @pxref{File Systems}), or @code{#f}, in which case
  27955. the bootloader will search the device containing the file specified by
  27956. the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
  27957. must @emph{not} be an OS device name such as @file{/dev/sda1}.
  27958. @item @code{multiboot-kernel} (default: @code{#f})
  27959. The kernel to boot in Multiboot-mode (@pxref{multiboot,,, grub, GNU GRUB
  27960. manual}). When this field is set, a Multiboot menu-entry is generated.
  27961. For example:
  27962. @lisp
  27963. (file-append mach "/boot/gnumach")
  27964. @end lisp
  27965. @item @code{multiboot-arguments} (default: @code{()})
  27966. The list of extra command-line arguments for the multiboot-kernel.
  27967. @item @code{multiboot-modules} (default: @code{()})
  27968. The list of commands for loading Multiboot modules. For example:
  27969. @lisp
  27970. (list (list (file-append hurd "/hurd/ext2fs.static") "ext2fs"
  27971. @dots{})
  27972. (list (file-append libc "/lib/ld.so.1") "exec"
  27973. @dots{}))
  27974. @end lisp
  27975. @end table
  27976. @end deftp
  27977. @cindex HDPI
  27978. @cindex HiDPI
  27979. @cindex resolution
  27980. @c FIXME: Write documentation once it's stable.
  27981. For now only GRUB has theme support. GRUB themes are created using
  27982. the @code{grub-theme} form, which is not fully documented yet.
  27983. @deftp {Data Type} grub-theme
  27984. Data type representing the configuration of the GRUB theme.
  27985. @table @asis
  27986. @item @code{gfxmode} (default: @code{'("auto")})
  27987. The GRUB @code{gfxmode} to set (a list of screen resolution strings,
  27988. @pxref{gfxmode,,, grub, GNU GRUB manual}).
  27989. @end table
  27990. @end deftp
  27991. @deffn {Scheme Procedure} grub-theme
  27992. Return the default GRUB theme used by the operating system if no
  27993. @code{theme} field is specified in @code{bootloader-configuration}
  27994. record.
  27995. It comes with a fancy background image displaying the GNU and Guix
  27996. logos.
  27997. @end deffn
  27998. For example, to override the default resolution, you may use something
  27999. like
  28000. @lisp
  28001. (bootloader
  28002. (bootloader-configuration
  28003. ;; @dots{}
  28004. (theme (grub-theme
  28005. (inherit (grub-theme))
  28006. (gfxmode '("1024x786x32" "auto"))))))
  28007. @end lisp
  28008. @node Invoking guix system
  28009. @section Invoking @code{guix system}
  28010. Once you have written an operating system declaration as seen in the
  28011. previous section, it can be @dfn{instantiated} using the @command{guix
  28012. system} command. The synopsis is:
  28013. @example
  28014. guix system @var{options}@dots{} @var{action} @var{file}
  28015. @end example
  28016. @var{file} must be the name of a file containing an
  28017. @code{operating-system} declaration. @var{action} specifies how the
  28018. operating system is instantiated. Currently the following values are
  28019. supported:
  28020. @table @code
  28021. @item search
  28022. Display available service type definitions that match the given regular
  28023. expressions, sorted by relevance:
  28024. @cindex HDPI
  28025. @cindex HiDPI
  28026. @cindex resolution
  28027. @example
  28028. $ guix system search console
  28029. name: console-fonts
  28030. location: gnu/services/base.scm:806:2
  28031. extends: shepherd-root
  28032. description: Install the given fonts on the specified ttys (fonts are per
  28033. + virtual console on GNU/Linux). The value of this service is a list of
  28034. + tty/font pairs. The font can be the name of a font provided by the `kbd'
  28035. + package or any valid argument to `setfont', as in this example:
  28036. +
  28037. + '(("tty1" . "LatGrkCyr-8x16")
  28038. + ("tty2" . (file-append
  28039. + font-tamzen
  28040. + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
  28041. + ("tty3" . (file-append
  28042. + font-terminus
  28043. + "/share/consolefonts/ter-132n"))) ; for HDPI
  28044. relevance: 9
  28045. name: mingetty
  28046. location: gnu/services/base.scm:1190:2
  28047. extends: shepherd-root
  28048. description: Provide console login using the `mingetty' program.
  28049. relevance: 2
  28050. name: login
  28051. location: gnu/services/base.scm:860:2
  28052. extends: pam
  28053. description: Provide a console log-in service as specified by its
  28054. + configuration value, a `login-configuration' object.
  28055. relevance: 2
  28056. @dots{}
  28057. @end example
  28058. As for @command{guix package --search}, the result is written in
  28059. @code{recutils} format, which makes it easy to filter the output
  28060. (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
  28061. @item reconfigure
  28062. Build the operating system described in @var{file}, activate it, and
  28063. switch to it@footnote{This action (and the related actions
  28064. @code{switch-generation} and @code{roll-back}) are usable only on
  28065. systems already running Guix System.}.
  28066. @quotation Note
  28067. @c The paragraph below refers to the problem discussed at
  28068. @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
  28069. It is highly recommended to run @command{guix pull} once before you run
  28070. @command{guix system reconfigure} for the first time (@pxref{Invoking
  28071. guix pull}). Failing to do that you would see an older version of Guix
  28072. once @command{reconfigure} has completed.
  28073. @end quotation
  28074. This effects all the configuration specified in @var{file}: user
  28075. accounts, system services, global package list, setuid programs, etc.
  28076. The command starts system services specified in @var{file} that are not
  28077. currently running; if a service is currently running this command will
  28078. arrange for it to be upgraded the next time it is stopped (e.g.@: by
  28079. @code{herd stop X} or @code{herd restart X}).
  28080. This command creates a new generation whose number is one greater than
  28081. the current generation (as reported by @command{guix system
  28082. list-generations}). If that generation already exists, it will be
  28083. overwritten. This behavior mirrors that of @command{guix package}
  28084. (@pxref{Invoking guix package}).
  28085. It also adds a bootloader menu entry for the new OS configuration,
  28086. ---unless @option{--no-bootloader} is passed. For GRUB, it moves
  28087. entries for older configurations to a submenu, allowing you to choose
  28088. an older system generation at boot time should you need it.
  28089. @cindex provenance tracking, of the operating system
  28090. Upon completion, the new system is deployed under
  28091. @file{/run/current-system}. This directory contains @dfn{provenance
  28092. meta-data}: the list of channels in use (@pxref{Channels}) and
  28093. @var{file} itself, when available. You can view it by running:
  28094. @example
  28095. guix system describe
  28096. @end example
  28097. This information is useful should you later want to inspect how this
  28098. particular generation was built. In fact, assuming @var{file} is
  28099. self-contained, you can later rebuild generation @var{n} of your
  28100. operating system with:
  28101. @example
  28102. guix time-machine \
  28103. -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
  28104. system reconfigure \
  28105. /var/guix/profiles/system-@var{n}-link/configuration.scm
  28106. @end example
  28107. You can think of it as some sort of built-in version control! Your
  28108. system is not just a binary artifact: @emph{it carries its own source}.
  28109. @xref{Service Reference, @code{provenance-service-type}}, for more
  28110. information on provenance tracking.
  28111. By default, @command{reconfigure} @emph{prevents you from downgrading
  28112. your system}, which could (re)introduce security vulnerabilities and
  28113. also cause problems with ``stateful'' services such as database
  28114. management systems. You can override that behavior by passing
  28115. @option{--allow-downgrades}.
  28116. @item switch-generation
  28117. @cindex generations
  28118. Switch to an existing system generation. This action atomically
  28119. switches the system profile to the specified system generation. It
  28120. also rearranges the system's existing bootloader menu entries. It
  28121. makes the menu entry for the specified system generation the default,
  28122. and it moves the entries for the other generations to a submenu, if
  28123. supported by the bootloader being used. The next time the system
  28124. boots, it will use the specified system generation.
  28125. The bootloader itself is not being reinstalled when using this
  28126. command. Thus, the installed bootloader is used with an updated
  28127. configuration file.
  28128. The target generation can be specified explicitly by its generation
  28129. number. For example, the following invocation would switch to system
  28130. generation 7:
  28131. @example
  28132. guix system switch-generation 7
  28133. @end example
  28134. The target generation can also be specified relative to the current
  28135. generation with the form @code{+N} or @code{-N}, where @code{+3} means
  28136. ``3 generations ahead of the current generation,'' and @code{-1} means
  28137. ``1 generation prior to the current generation.'' When specifying a
  28138. negative value such as @code{-1}, you must precede it with @code{--} to
  28139. prevent it from being parsed as an option. For example:
  28140. @example
  28141. guix system switch-generation -- -1
  28142. @end example
  28143. Currently, the effect of invoking this action is @emph{only} to switch
  28144. the system profile to an existing generation and rearrange the
  28145. bootloader menu entries. To actually start using the target system
  28146. generation, you must reboot after running this action. In the future,
  28147. it will be updated to do the same things as @command{reconfigure},
  28148. like activating and deactivating services.
  28149. This action will fail if the specified generation does not exist.
  28150. @item roll-back
  28151. @cindex rolling back
  28152. Switch to the preceding system generation. The next time the system
  28153. boots, it will use the preceding system generation. This is the inverse
  28154. of @command{reconfigure}, and it is exactly the same as invoking
  28155. @command{switch-generation} with an argument of @code{-1}.
  28156. Currently, as with @command{switch-generation}, you must reboot after
  28157. running this action to actually start using the preceding system
  28158. generation.
  28159. @item delete-generations
  28160. @cindex deleting system generations
  28161. @cindex saving space
  28162. Delete system generations, making them candidates for garbage collection
  28163. (@pxref{Invoking guix gc}, for information on how to run the ``garbage
  28164. collector'').
  28165. This works in the same way as @samp{guix package --delete-generations}
  28166. (@pxref{Invoking guix package, @option{--delete-generations}}). With no
  28167. arguments, all system generations but the current one are deleted:
  28168. @example
  28169. guix system delete-generations
  28170. @end example
  28171. You can also select the generations you want to delete. The example below
  28172. deletes all the system generations that are more than two months old:
  28173. @example
  28174. guix system delete-generations 2m
  28175. @end example
  28176. Running this command automatically reinstalls the bootloader with an updated
  28177. list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
  28178. longer lists the generations that have been deleted.
  28179. @item build
  28180. Build the derivation of the operating system, which includes all the
  28181. configuration files and programs needed to boot and run the system.
  28182. This action does not actually install anything.
  28183. @item init
  28184. Populate the given directory with all the files necessary to run the
  28185. operating system specified in @var{file}. This is useful for first-time
  28186. installations of Guix System. For instance:
  28187. @example
  28188. guix system init my-os-config.scm /mnt
  28189. @end example
  28190. copies to @file{/mnt} all the store items required by the configuration
  28191. specified in @file{my-os-config.scm}. This includes configuration
  28192. files, packages, and so on. It also creates other essential files
  28193. needed for the system to operate correctly---e.g., the @file{/etc},
  28194. @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
  28195. This command also installs bootloader on the targets specified in
  28196. @file{my-os-config}, unless the @option{--no-bootloader} option was
  28197. passed.
  28198. @item vm
  28199. @cindex virtual machine
  28200. @cindex VM
  28201. @anchor{guix system vm}
  28202. Build a virtual machine (VM) that contains the operating system declared
  28203. in @var{file}, and return a script to run that VM.
  28204. @quotation Note
  28205. The @code{vm} action and others below
  28206. can use KVM support in the Linux-libre kernel. Specifically, if the
  28207. machine has hardware virtualization support, the corresponding
  28208. KVM kernel module should be loaded, and the @file{/dev/kvm} device node
  28209. must exist and be readable and writable by the user and by the
  28210. build users of the daemon (@pxref{Build Environment Setup}).
  28211. @end quotation
  28212. Arguments given to the script are passed to QEMU as in the example
  28213. below, which enables networking and requests 1@tie{}GiB of RAM for the
  28214. emulated machine:
  28215. @example
  28216. $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -nic user,model=virtio-net-pci
  28217. @end example
  28218. It's possible to combine the two steps into one:
  28219. @example
  28220. $ $(guix system vm my-config.scm) -m 1024 -smp 2 -nic user,model=virtio-net-pci
  28221. @end example
  28222. The VM shares its store with the host system.
  28223. By default, the root file system of the VM is mounted volatile; the
  28224. @option{--persistent} option can be provided to make it persistent
  28225. instead. In that case, the VM disk-image file will be copied from the
  28226. store to the @env{TMPDIR} directory to make it writable.
  28227. Additional file systems can be shared between the host and the VM using
  28228. the @option{--share} and @option{--expose} command-line options: the former
  28229. specifies a directory to be shared with write access, while the latter
  28230. provides read-only access to the shared directory.
  28231. The example below creates a VM in which the user's home directory is
  28232. accessible read-only, and where the @file{/exchange} directory is a
  28233. read-write mapping of @file{$HOME/tmp} on the host:
  28234. @example
  28235. guix system vm my-config.scm \
  28236. --expose=$HOME --share=$HOME/tmp=/exchange
  28237. @end example
  28238. On GNU/Linux, the default is to boot directly to the kernel; this has
  28239. the advantage of requiring only a very tiny root disk image since the
  28240. store of the host can then be mounted.
  28241. The @option{--full-boot} option forces a complete boot sequence, starting
  28242. with the bootloader. This requires more disk space since a root image
  28243. containing at least the kernel, initrd, and bootloader data files must
  28244. be created.
  28245. The @option{--image-size} option can be used to specify the size of the
  28246. image.
  28247. The @option{--no-graphic} option will instruct @command{guix system} to
  28248. spawn a headless VM that will use the invoking tty for IO. Among other
  28249. things, this enables copy-pasting, and scrollback. Use the @kbd{ctrl-a}
  28250. prefix to issue QEMU commands; e.g. @kbd{ctrl-a h} prints a help,
  28251. @kbd{ctrl-a x} quits the VM, and @kbd{ctrl-a c} switches between the
  28252. QEMU monitor and the VM.
  28253. @cindex System images, creation in various formats
  28254. @cindex Creating system images in various formats
  28255. @item image
  28256. @cindex image, creating disk images
  28257. The @code{image} command can produce various image types. The image
  28258. type can be selected using the @option{--image-type} option. It
  28259. defaults to @code{efi-raw}. When its value is @code{iso9660}, the
  28260. @option{--label} option can be used to specify a volume ID with
  28261. @code{image}. By default, the root file system of a disk image is
  28262. mounted non-volatile; the @option{--volatile} option can be provided to
  28263. make it volatile instead. When using @code{image}, the bootloader
  28264. installed on the generated image is taken from the provided
  28265. @code{operating-system} definition. The following example demonstrates
  28266. how to generate an image that uses the @code{grub-efi-bootloader}
  28267. bootloader and boot it with QEMU:
  28268. @example
  28269. image=$(guix system image --image-type=qcow2 \
  28270. gnu/system/examples/lightweight-desktop.tmpl)
  28271. cp $image /tmp/my-image.qcow2
  28272. chmod +w /tmp/my-image.qcow2
  28273. qemu-system-x86_64 -enable-kvm -hda /tmp/my-image.qcow2 -m 1000 \
  28274. -bios $(guix build ovmf)/share/firmware/ovmf_x64.bin
  28275. @end example
  28276. When using the @code{efi-raw} image type, a raw disk image is produced;
  28277. it can be copied as is to a USB stick, for instance. Assuming
  28278. @code{/dev/sdc} is the device corresponding to a USB stick, one can copy
  28279. the image to it using the following command:
  28280. @example
  28281. # dd if=$(guix system image my-os.scm) of=/dev/sdc status=progress
  28282. @end example
  28283. The @code{--list-image-types} command lists all the available image
  28284. types.
  28285. @cindex creating virtual machine images
  28286. When using the @code{qcow2} image type, the returned image is in qcow2
  28287. format, which the QEMU emulator can efficiently use. @xref{Running Guix
  28288. in a VM}, for more information on how to run the image in a virtual
  28289. machine. The @code{grub-bootloader} bootloader is always used
  28290. independently of what is declared in the @code{operating-system} file
  28291. passed as argument. This is to make it easier to work with QEMU, which
  28292. uses the SeaBIOS BIOS by default, expecting a bootloader to be installed
  28293. in the Master Boot Record (MBR).
  28294. @cindex docker-image, creating docker images
  28295. When using the @code{docker} image type, a Docker image is produced.
  28296. Guix builds the image from scratch, not from a pre-existing Docker base
  28297. image. As a result, it contains @emph{exactly} what you define in the
  28298. operating system configuration file. You can then load the image and
  28299. launch a Docker container using commands like the following:
  28300. @example
  28301. image_id="$(docker load < guix-system-docker-image.tar.gz)"
  28302. container_id="$(docker create $image_id)"
  28303. docker start $container_id
  28304. @end example
  28305. This command starts a new Docker container from the specified image. It
  28306. will boot the Guix system in the usual manner, which means it will
  28307. start any services you have defined in the operating system
  28308. configuration. You can get an interactive shell running in the container
  28309. using @command{docker exec}:
  28310. @example
  28311. docker exec -ti $container_id /run/current-system/profile/bin/bash --login
  28312. @end example
  28313. Depending on what you run in the Docker container, it
  28314. may be necessary to give the container additional permissions. For
  28315. example, if you intend to build software using Guix inside of the Docker
  28316. container, you may need to pass the @option{--privileged} option to
  28317. @code{docker create}.
  28318. Last, the @option{--network} option applies to @command{guix system
  28319. docker-image}: it produces an image where network is supposedly shared
  28320. with the host, and thus without services like nscd or NetworkManager.
  28321. @item container
  28322. Return a script to run the operating system declared in @var{file}
  28323. within a container. Containers are a set of lightweight isolation
  28324. mechanisms provided by the kernel Linux-libre. Containers are
  28325. substantially less resource-demanding than full virtual machines since
  28326. the kernel, shared objects, and other resources can be shared with the
  28327. host system; this also means they provide thinner isolation.
  28328. Currently, the script must be run as root in order to support more than
  28329. a single user and group. The container shares its store with the host
  28330. system.
  28331. As with the @code{vm} action (@pxref{guix system vm}), additional file
  28332. systems to be shared between the host and container can be specified
  28333. using the @option{--share} and @option{--expose} options:
  28334. @example
  28335. guix system container my-config.scm \
  28336. --expose=$HOME --share=$HOME/tmp=/exchange
  28337. @end example
  28338. @quotation Note
  28339. This option requires Linux-libre 3.19 or newer.
  28340. @end quotation
  28341. @end table
  28342. @var{options} can contain any of the common build options (@pxref{Common
  28343. Build Options}). In addition, @var{options} can contain one of the
  28344. following:
  28345. @table @option
  28346. @item --expression=@var{expr}
  28347. @itemx -e @var{expr}
  28348. Consider the operating-system @var{expr} evaluates to.
  28349. This is an alternative to specifying a file which evaluates to an
  28350. operating system.
  28351. This is used to generate the Guix system installer @pxref{Building the
  28352. Installation Image}).
  28353. @item --system=@var{system}
  28354. @itemx -s @var{system}
  28355. Attempt to build for @var{system} instead of the host system type.
  28356. This works as per @command{guix build} (@pxref{Invoking guix build}).
  28357. @item --derivation
  28358. @itemx -d
  28359. Return the derivation file name of the given operating system without
  28360. building anything.
  28361. @cindex provenance tracking, of the operating system
  28362. @item --save-provenance
  28363. As discussed above, @command{guix system init} and @command{guix system
  28364. reconfigure} always save provenance information @i{via} a dedicated
  28365. service (@pxref{Service Reference, @code{provenance-service-type}}).
  28366. However, other commands don't do that by default. If you wish to, say,
  28367. create a virtual machine image that contains provenance information, you
  28368. can run:
  28369. @example
  28370. guix system image -t qcow2 --save-provenance config.scm
  28371. @end example
  28372. That way, the resulting image will effectively ``embed its own source''
  28373. in the form of meta-data in @file{/run/current-system}. With that
  28374. information, one can rebuild the image to make sure it really contains
  28375. what it pretends to contain; or they could use that to derive a variant
  28376. of the image.
  28377. @item --image-type=@var{type}
  28378. @itemx -t @var{type}
  28379. For the @code{image} action, create an image with given @var{type}.
  28380. When this option is omitted, @command{guix system} uses the
  28381. @code{efi-raw} image type.
  28382. @cindex ISO-9660 format
  28383. @cindex CD image format
  28384. @cindex DVD image format
  28385. @option{--image-type=iso9660} produces an ISO-9660 image, suitable
  28386. for burning on CDs and DVDs.
  28387. @item --image-size=@var{size}
  28388. For the @code{image} action, create an image of the given @var{size}.
  28389. @var{size} may be a number of bytes, or it may include a unit as a
  28390. suffix (@pxref{Block size, size specifications,, coreutils, GNU
  28391. Coreutils}).
  28392. When this option is omitted, @command{guix system} computes an estimate
  28393. of the image size as a function of the size of the system declared in
  28394. @var{file}.
  28395. @item --network
  28396. @itemx -N
  28397. For the @code{container} action, allow containers to access the host network,
  28398. that is, do not create a network namespace.
  28399. @item --root=@var{file}
  28400. @itemx -r @var{file}
  28401. Make @var{file} a symlink to the result, and register it as a garbage
  28402. collector root.
  28403. @item --skip-checks
  28404. Skip pre-installation safety checks.
  28405. By default, @command{guix system init} and @command{guix system
  28406. reconfigure} perform safety checks: they make sure the file systems that
  28407. appear in the @code{operating-system} declaration actually exist
  28408. (@pxref{File Systems}), and that any Linux kernel modules that may be
  28409. needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
  28410. RAM Disk}). Passing this option skips these tests altogether.
  28411. @item --allow-downgrades
  28412. Instruct @command{guix system reconfigure} to allow system downgrades.
  28413. By default, @command{reconfigure} prevents you from downgrading your
  28414. system. It achieves that by comparing the provenance info of your
  28415. system (shown by @command{guix system describe}) with that of your
  28416. @command{guix} command (shown by @command{guix describe}). If the
  28417. commits for @command{guix} are not descendants of those used for your
  28418. system, @command{guix system reconfigure} errors out. Passing
  28419. @option{--allow-downgrades} allows you to bypass these checks.
  28420. @quotation Note
  28421. Make sure you understand its security implications before using
  28422. @option{--allow-downgrades}.
  28423. @end quotation
  28424. @cindex on-error
  28425. @cindex on-error strategy
  28426. @cindex error strategy
  28427. @item --on-error=@var{strategy}
  28428. Apply @var{strategy} when an error occurs when reading @var{file}.
  28429. @var{strategy} may be one of the following:
  28430. @table @code
  28431. @item nothing-special
  28432. Report the error concisely and exit. This is the default strategy.
  28433. @item backtrace
  28434. Likewise, but also display a backtrace.
  28435. @item debug
  28436. Report the error and enter Guile's debugger. From there, you can run
  28437. commands such as @code{,bt} to get a backtrace, @code{,locals} to
  28438. display local variable values, and more generally inspect the state of the
  28439. program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
  28440. a list of available debugging commands.
  28441. @end table
  28442. @end table
  28443. Once you have built, configured, re-configured, and re-re-configured
  28444. your Guix installation, you may find it useful to list the operating
  28445. system generations available on disk---and that you can choose from the
  28446. bootloader boot menu:
  28447. @table @code
  28448. @item describe
  28449. Describe the running system generation: its file name, the kernel and
  28450. bootloader used, etc., as well as provenance information when available.
  28451. @quotation Note
  28452. The @emph{running} system generation---referred to by
  28453. @file{/run/current-system}---is not necessarily the @emph{current}
  28454. system generation---referred to by @file{/var/guix/profiles/system}: it
  28455. differs when, for instance, you chose from the bootloader menu to boot
  28456. an older generation.
  28457. It can also differ from the @emph{booted} system generation---referred
  28458. to by @file{/run/booted-system}---for instance because you reconfigured
  28459. the system in the meantime.
  28460. @end quotation
  28461. @item list-generations
  28462. List a summary of each generation of the operating system available on
  28463. disk, in a human-readable way. This is similar to the
  28464. @option{--list-generations} option of @command{guix package}
  28465. (@pxref{Invoking guix package}).
  28466. Optionally, one can specify a pattern, with the same syntax that is used
  28467. in @command{guix package --list-generations}, to restrict the list of
  28468. generations displayed. For instance, the following command displays
  28469. generations that are up to 10 days old:
  28470. @example
  28471. $ guix system list-generations 10d
  28472. @end example
  28473. @end table
  28474. The @command{guix system} command has even more to offer! The following
  28475. sub-commands allow you to visualize how your system services relate to
  28476. each other:
  28477. @anchor{system-extension-graph}
  28478. @table @code
  28479. @item extension-graph
  28480. Emit to standard output the @dfn{service
  28481. extension graph} of the operating system defined in @var{file}
  28482. (@pxref{Service Composition}, for more information on service
  28483. extensions). By default the output is in Dot/Graphviz format, but you
  28484. can choose a different format with @option{--graph-backend}, as with
  28485. @command{guix graph} (@pxref{Invoking guix graph, @option{--backend}}):
  28486. The command:
  28487. @example
  28488. $ guix system extension-graph @var{file} | xdot -
  28489. @end example
  28490. shows the extension relations among services.
  28491. @anchor{system-shepherd-graph}
  28492. @item shepherd-graph
  28493. Emit to standard output the @dfn{dependency
  28494. graph} of shepherd services of the operating system defined in
  28495. @var{file}. @xref{Shepherd Services}, for more information and for an
  28496. example graph.
  28497. Again, the default output format is Dot/Graphviz, but you can pass
  28498. @option{--graph-backend} to select a different one.
  28499. @end table
  28500. @node Invoking guix deploy
  28501. @section Invoking @code{guix deploy}
  28502. We've already seen @code{operating-system} declarations used to manage a
  28503. machine's configuration locally. Suppose you need to configure multiple
  28504. machines, though---perhaps you're managing a service on the web that's
  28505. comprised of several servers. @command{guix deploy} enables you to use those
  28506. same @code{operating-system} declarations to manage multiple remote hosts at
  28507. once as a logical ``deployment''.
  28508. @quotation Note
  28509. The functionality described in this section is still under development
  28510. and is subject to change. Get in touch with us on
  28511. @email{guix-devel@@gnu.org}!
  28512. @end quotation
  28513. @example
  28514. guix deploy @var{file}
  28515. @end example
  28516. Such an invocation will deploy the machines that the code within @var{file}
  28517. evaluates to. As an example, @var{file} might contain a definition like this:
  28518. @lisp
  28519. ;; This is a Guix deployment of a "bare bones" setup, with
  28520. ;; no X11 display server, to a machine with an SSH daemon
  28521. ;; listening on localhost:2222. A configuration such as this
  28522. ;; may be appropriate for virtual machine with ports
  28523. ;; forwarded to the host's loopback interface.
  28524. (use-service-modules networking ssh)
  28525. (use-package-modules bootloaders)
  28526. (define %system
  28527. (operating-system
  28528. (host-name "gnu-deployed")
  28529. (timezone "Etc/UTC")
  28530. (bootloader (bootloader-configuration
  28531. (bootloader grub-bootloader)
  28532. (targets '("/dev/vda"))
  28533. (terminal-outputs '(console))))
  28534. (file-systems (cons (file-system
  28535. (mount-point "/")
  28536. (device "/dev/vda1")
  28537. (type "ext4"))
  28538. %base-file-systems))
  28539. (services
  28540. (append (list (service dhcp-client-service-type)
  28541. (service openssh-service-type
  28542. (openssh-configuration
  28543. (permit-root-login #t)
  28544. (allow-empty-passwords? #t))))
  28545. %base-services))))
  28546. (list (machine
  28547. (operating-system %system)
  28548. (environment managed-host-environment-type)
  28549. (configuration (machine-ssh-configuration
  28550. (host-name "localhost")
  28551. (system "x86_64-linux")
  28552. (user "alice")
  28553. (identity "./id_rsa")
  28554. (port 2222)))))
  28555. @end lisp
  28556. The file should evaluate to a list of @var{machine} objects. This example,
  28557. upon being deployed, will create a new generation on the remote system
  28558. realizing the @code{operating-system} declaration @code{%system}.
  28559. @code{environment} and @code{configuration} specify how the machine should be
  28560. provisioned---that is, how the computing resources should be created and
  28561. managed. The above example does not create any resources, as a
  28562. @code{'managed-host} is a machine that is already running the Guix system and
  28563. available over the network. This is a particularly simple case; a more
  28564. complex deployment may involve, for example, starting virtual machines through
  28565. a Virtual Private Server (VPS) provider. In such a case, a different
  28566. @var{environment} type would be used.
  28567. Do note that you first need to generate a key pair on the coordinator machine
  28568. to allow the daemon to export signed archives of files from the store
  28569. (@pxref{Invoking guix archive}), though this step is automatic on Guix
  28570. System:
  28571. @example
  28572. # guix archive --generate-key
  28573. @end example
  28574. @noindent
  28575. Each target machine must authorize the key of the master machine so that it
  28576. accepts store items it receives from the coordinator:
  28577. @example
  28578. # guix archive --authorize < coordinator-public-key.txt
  28579. @end example
  28580. @code{user}, in this example, specifies the name of the user account to log in
  28581. as to perform the deployment. Its default value is @code{root}, but root
  28582. login over SSH may be forbidden in some cases. To work around this,
  28583. @command{guix deploy} can log in as an unprivileged user and employ
  28584. @code{sudo} to escalate privileges. This will only work if @code{sudo} is
  28585. currently installed on the remote and can be invoked non-interactively as
  28586. @code{user}. That is, the line in @code{sudoers} granting @code{user} the
  28587. ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
  28588. be accomplished with the following operating system configuration snippet:
  28589. @lisp
  28590. (use-modules ...
  28591. (gnu system)) ;for %sudoers-specification
  28592. (define %user "username")
  28593. (operating-system
  28594. ...
  28595. (sudoers-file
  28596. (plain-file "sudoers"
  28597. (string-append (plain-file-content %sudoers-specification)
  28598. (format #f "~a ALL = NOPASSWD: ALL~%"
  28599. %user)))))
  28600. @end lisp
  28601. For more information regarding the format of the @file{sudoers} file,
  28602. consult @command{man sudoers}.
  28603. Once you've deployed a system on a set of machines, you may find it
  28604. useful to run a command on all of them. The @option{--execute} or
  28605. @option{-x} option lets you do that; the example below runs
  28606. @command{uname -a} on all the machines listed in the deployment file:
  28607. @example
  28608. guix deploy @var{file} -x -- uname -a
  28609. @end example
  28610. One thing you may often need to do after deployment is restart specific
  28611. services on all the machines, which you can do like so:
  28612. @example
  28613. guix deploy @var{file} -x -- herd restart @var{service}
  28614. @end example
  28615. The @command{guix deploy -x} command returns zero if and only if the
  28616. command succeeded on all the machines.
  28617. @c FIXME/TODO: Separate the API doc from the CLI doc.
  28618. Below are the data types you need to know about when writing a
  28619. deployment file.
  28620. @deftp {Data Type} machine
  28621. This is the data type representing a single machine in a heterogeneous Guix
  28622. deployment.
  28623. @table @asis
  28624. @item @code{operating-system}
  28625. The object of the operating system configuration to deploy.
  28626. @item @code{environment}
  28627. An @code{environment-type} describing how the machine should be provisioned.
  28628. @item @code{configuration} (default: @code{#f})
  28629. An object describing the configuration for the machine's @code{environment}.
  28630. If the @code{environment} has a default configuration, @code{#f} may be used.
  28631. If @code{#f} is used for an environment with no default configuration,
  28632. however, an error will be thrown.
  28633. @end table
  28634. @end deftp
  28635. @deftp {Data Type} machine-ssh-configuration
  28636. This is the data type representing the SSH client parameters for a machine
  28637. with an @code{environment} of @code{managed-host-environment-type}.
  28638. @table @asis
  28639. @item @code{host-name}
  28640. @item @code{build-locally?} (default: @code{#t})
  28641. If false, system derivations will be built on the machine being deployed to.
  28642. @item @code{system}
  28643. The system type describing the architecture of the machine being deployed
  28644. to---e.g., @code{"x86_64-linux"}.
  28645. @item @code{authorize?} (default: @code{#t})
  28646. If true, the coordinator's signing key will be added to the remote's ACL
  28647. keyring.
  28648. @item @code{port} (default: @code{22})
  28649. @item @code{user} (default: @code{"root"})
  28650. @item @code{identity} (default: @code{#f})
  28651. If specified, the path to the SSH private key to use to authenticate with the
  28652. remote host.
  28653. @item @code{host-key} (default: @code{#f})
  28654. This should be the SSH host key of the machine, which looks like this:
  28655. @example
  28656. ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
  28657. @end example
  28658. When @code{host-key} is @code{#f}, the server is authenticated against
  28659. the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
  28660. client does.
  28661. @item @code{allow-downgrades?} (default: @code{#f})
  28662. Whether to allow potential downgrades.
  28663. Like @command{guix system reconfigure}, @command{guix deploy} compares
  28664. the channel commits currently deployed on the remote host (as returned
  28665. by @command{guix system describe}) to those currently in use (as
  28666. returned by @command{guix describe}) to determine whether commits
  28667. currently in use are descendants of those deployed. When this is not
  28668. the case and @code{allow-downgrades?} is false, it raises an error.
  28669. This ensures you do not accidentally downgrade remote machines.
  28670. @item @code{safety-checks?} (default: @code{#t})
  28671. Whether to perform ``safety checks'' before deployment. This includes
  28672. verifying that devices and file systems referred to in the operating
  28673. system configuration actually exist on the target machine, and making
  28674. sure that Linux modules required to access storage devices at boot time
  28675. are listed in the @code{initrd-modules} field of the operating system.
  28676. These safety checks ensure that you do not inadvertently deploy a system
  28677. that would fail to boot. Be careful before turning them off!
  28678. @end table
  28679. @end deftp
  28680. @deftp {Data Type} digital-ocean-configuration
  28681. This is the data type describing the Droplet that should be created for a
  28682. machine with an @code{environment} of @code{digital-ocean-environment-type}.
  28683. @table @asis
  28684. @item @code{ssh-key}
  28685. The path to the SSH private key to use to authenticate with the remote
  28686. host. In the future, this field may not exist.
  28687. @item @code{tags}
  28688. A list of string ``tags'' that uniquely identify the machine. Must be given
  28689. such that no two machines in the deployment have the same set of tags.
  28690. @item @code{region}
  28691. A Digital Ocean region slug, such as @code{"nyc3"}.
  28692. @item @code{size}
  28693. A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
  28694. @item @code{enable-ipv6?}
  28695. Whether or not the droplet should be created with IPv6 networking.
  28696. @end table
  28697. @end deftp
  28698. @node Running Guix in a VM
  28699. @section Running Guix in a Virtual Machine
  28700. @cindex virtual machine
  28701. To run Guix in a virtual machine (VM), one can use the pre-built Guix VM
  28702. image distributed at
  28703. @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.qcow2}.
  28704. This image is a compressed image in QCOW format. You can pass it to an
  28705. emulator such as @uref{https://qemu.org/, QEMU} (see below for details).
  28706. This image boots the Xfce graphical environment and it contains some
  28707. commonly used tools. You can install more software in the image by running
  28708. @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
  28709. also reconfigure the system based on its initial configuration file available
  28710. as @file{/run/current-system/configuration.scm} (@pxref{Using the
  28711. Configuration System}).
  28712. Instead of using this pre-built image, one can also build their own
  28713. image using @command{guix system image} (@pxref{Invoking guix system}).
  28714. @cindex QEMU
  28715. If you built your own image, you must copy it out of the store
  28716. (@pxref{The Store}) and give yourself permission to write to the copy
  28717. before you can use it. When invoking QEMU, you must choose a system
  28718. emulator that is suitable for your hardware platform. Here is a minimal
  28719. QEMU invocation that will boot the result of @command{guix system
  28720. image -t qcow2} on x86_64 hardware:
  28721. @example
  28722. $ qemu-system-x86_64 \
  28723. -nic user,model=virtio-net-pci \
  28724. -enable-kvm -m 1024 \
  28725. -device virtio-blk,drive=myhd \
  28726. -drive if=none,file=/tmp/qemu-image,id=myhd
  28727. @end example
  28728. Here is what each of these options means:
  28729. @table @code
  28730. @item qemu-system-x86_64
  28731. This specifies the hardware platform to emulate. This should match the
  28732. host.
  28733. @item -nic user,model=virtio-net-pci
  28734. Enable the unprivileged user-mode network stack. The guest OS can
  28735. access the host but not vice versa. This is the simplest way to get the
  28736. guest OS online. @code{model} specifies which network device to emulate:
  28737. @code{virtio-net-pci} is a special device made for virtualized operating
  28738. systems and recommended for most uses. Assuming your hardware platform is
  28739. x86_64, you can get a list of available NIC models by running
  28740. @command{qemu-system-x86_64 -nic model=help}.
  28741. @item -enable-kvm
  28742. If your system has hardware virtualization extensions, enabling the
  28743. virtual machine support (KVM) of the Linux kernel will make things run
  28744. faster.
  28745. @c To run Xfce + 'guix pull', we need at least 1G of RAM.
  28746. @item -m 1024
  28747. RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
  28748. which may be insufficient for some operations.
  28749. @item -device virtio-blk,drive=myhd
  28750. Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
  28751. ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
  28752. better performance than if it were emulating a complete disk drive. See the
  28753. QEMU and KVM documentation for more info.
  28754. @item -drive if=none,file=/tmp/qemu-image,id=myhd
  28755. Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing
  28756. store of the ``myhd'' drive.
  28757. @end table
  28758. The default @command{run-vm.sh} script that is returned by an invocation of
  28759. @command{guix system vm} does not add a @command{-nic user} flag by default.
  28760. To get network access from within the vm add the @code{(dhcp-client-service)}
  28761. to your system definition and start the VM using
  28762. @command{$(guix system vm config.scm) -nic user}. An important caveat of using
  28763. @command{-nic user} for networking is that @command{ping} will not work, because
  28764. it uses the ICMP protocol. You'll have to use a different command to check for
  28765. network connectivity, for example @command{guix download}.
  28766. @subsection Connecting Through SSH
  28767. @cindex SSH
  28768. @cindex SSH server
  28769. To enable SSH inside a VM you need to add an SSH server like
  28770. @code{openssh-service-type} to your VM (@pxref{Networking Services,
  28771. @code{openssh-service-type}}). In addition you need to forward the SSH port,
  28772. 22 by default, to the host. You can do this with
  28773. @example
  28774. $(guix system vm config.scm) -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
  28775. @end example
  28776. To connect to the VM you can run
  28777. @example
  28778. ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022 localhost
  28779. @end example
  28780. The @command{-p} tells @command{ssh} the port you want to connect to.
  28781. @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
  28782. every time you modify your @command{config.scm} file and the
  28783. @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
  28784. connection to an unknown host every time you connect.
  28785. @quotation Note
  28786. If you find the above @samp{hostfwd} example not to be working (e.g.,
  28787. your SSH client hangs attempting to connect to the mapped port of your
  28788. VM), make sure that your Guix System VM has networking support, such as
  28789. by using the @code{dhcp-client-service-type} service type.
  28790. @end quotation
  28791. @subsection Using @command{virt-viewer} with Spice
  28792. As an alternative to the default @command{qemu} graphical client you can
  28793. use the @command{remote-viewer} from the @command{virt-viewer} package. To
  28794. connect pass the @command{-spice port=5930,disable-ticketing} flag to
  28795. @command{qemu}. See previous section for further information on how to do this.
  28796. Spice also allows you to do some nice stuff like share your clipboard with your
  28797. VM@. To enable that you'll also have to pass the following flags to @command{qemu}:
  28798. @example
  28799. -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
  28800. -chardev spicevmc,name=vdagent,id=vdagent
  28801. -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,\
  28802. name=com.redhat.spice.0
  28803. @end example
  28804. You'll also need to add the @code{(spice-vdagent-service)} to your
  28805. system definition (@pxref{Miscellaneous Services, Spice service}).
  28806. @node Defining Services
  28807. @section Defining Services
  28808. The previous sections show the available services and how one can combine
  28809. them in an @code{operating-system} declaration. But how do we define
  28810. them in the first place? And what is a service anyway?
  28811. @menu
  28812. * Service Composition:: The model for composing services.
  28813. * Service Types and Services:: Types and services.
  28814. * Service Reference:: API reference.
  28815. * Shepherd Services:: A particular type of service.
  28816. * Complex Configurations:: Defining bindings for complex configurations.
  28817. @end menu
  28818. @node Service Composition
  28819. @subsection Service Composition
  28820. @cindex services
  28821. @cindex daemons
  28822. Here we define a @dfn{service} as, broadly, something that extends the
  28823. functionality of the operating system. Often a service is a process---a
  28824. @dfn{daemon}---started when the system boots: a secure shell server, a
  28825. Web server, the Guix build daemon, etc. Sometimes a service is a daemon
  28826. whose execution can be triggered by another daemon---e.g., an FTP server
  28827. started by @command{inetd} or a D-Bus service activated by
  28828. @command{dbus-daemon}. Occasionally, a service does not map to a
  28829. daemon. For instance, the ``account'' service collects user accounts
  28830. and makes sure they exist when the system runs; the ``udev'' service
  28831. collects device management rules and makes them available to the eudev
  28832. daemon; the @file{/etc} service populates the @file{/etc} directory
  28833. of the system.
  28834. @cindex service extensions
  28835. Guix system services are connected by @dfn{extensions}. For instance, the
  28836. secure shell service @emph{extends} the Shepherd---the
  28837. initialization system, running as PID@tie{}1---by giving it the command
  28838. lines to start and stop the secure shell daemon (@pxref{Networking
  28839. Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
  28840. service by passing it its @file{.service} specification, and extends the
  28841. udev service by passing it device management rules (@pxref{Desktop
  28842. Services, @code{upower-service}}); the Guix daemon service extends the
  28843. Shepherd by passing it the command lines to start and stop the daemon,
  28844. and extends the account service by passing it a list of required build
  28845. user accounts (@pxref{Base Services}).
  28846. All in all, services and their ``extends'' relations form a directed
  28847. acyclic graph (DAG). If we represent services as boxes and extensions
  28848. as arrows, a typical system might provide something like this:
  28849. @image{images/service-graph,,5in,Typical service extension graph.}
  28850. @cindex system service
  28851. At the bottom, we see the @dfn{system service}, which produces the
  28852. directory containing everything to run and boot the system, as returned
  28853. by the @command{guix system build} command. @xref{Service Reference},
  28854. to learn about the other service types shown here.
  28855. @xref{system-extension-graph, the @command{guix system extension-graph}
  28856. command}, for information on how to generate this representation for a
  28857. particular operating system definition.
  28858. @cindex service types
  28859. Technically, developers can define @dfn{service types} to express these
  28860. relations. There can be any number of services of a given type on the
  28861. system---for instance, a system running two instances of the GNU secure
  28862. shell server (lsh) has two instances of @code{lsh-service-type}, with
  28863. different parameters.
  28864. The following section describes the programming interface for service
  28865. types and services.
  28866. @node Service Types and Services
  28867. @subsection Service Types and Services
  28868. A @dfn{service type} is a node in the DAG described above. Let us start
  28869. with a simple example, the service type for the Guix build daemon
  28870. (@pxref{Invoking guix-daemon}):
  28871. @lisp
  28872. (define guix-service-type
  28873. (service-type
  28874. (name 'guix)
  28875. (extensions
  28876. (list (service-extension shepherd-root-service-type guix-shepherd-service)
  28877. (service-extension account-service-type guix-accounts)
  28878. (service-extension activation-service-type guix-activation)))
  28879. (default-value (guix-configuration))))
  28880. @end lisp
  28881. @noindent
  28882. It defines three things:
  28883. @enumerate
  28884. @item
  28885. A name, whose sole purpose is to make inspection and debugging easier.
  28886. @item
  28887. A list of @dfn{service extensions}, where each extension designates the
  28888. target service type and a procedure that, given the parameters of the
  28889. service, returns a list of objects to extend the service of that type.
  28890. Every service type has at least one service extension. The only
  28891. exception is the @dfn{boot service type}, which is the ultimate service.
  28892. @item
  28893. Optionally, a default value for instances of this type.
  28894. @end enumerate
  28895. In this example, @code{guix-service-type} extends three services:
  28896. @table @code
  28897. @item shepherd-root-service-type
  28898. The @code{guix-shepherd-service} procedure defines how the Shepherd
  28899. service is extended. Namely, it returns a @code{<shepherd-service>}
  28900. object that defines how @command{guix-daemon} is started and stopped
  28901. (@pxref{Shepherd Services}).
  28902. @item account-service-type
  28903. This extension for this service is computed by @code{guix-accounts},
  28904. which returns a list of @code{user-group} and @code{user-account}
  28905. objects representing the build user accounts (@pxref{Invoking
  28906. guix-daemon}).
  28907. @item activation-service-type
  28908. Here @code{guix-activation} is a procedure that returns a gexp, which is
  28909. a code snippet to run at ``activation time''---e.g., when the service is
  28910. booted.
  28911. @end table
  28912. A service of this type is instantiated like this:
  28913. @lisp
  28914. (service guix-service-type
  28915. (guix-configuration
  28916. (build-accounts 5)
  28917. (extra-options '("--gc-keep-derivations"))))
  28918. @end lisp
  28919. The second argument to the @code{service} form is a value representing
  28920. the parameters of this specific service instance.
  28921. @xref{guix-configuration-type, @code{guix-configuration}}, for
  28922. information about the @code{guix-configuration} data type. When the
  28923. value is omitted, the default value specified by
  28924. @code{guix-service-type} is used:
  28925. @lisp
  28926. (service guix-service-type)
  28927. @end lisp
  28928. @code{guix-service-type} is quite simple because it extends other
  28929. services but is not extensible itself.
  28930. @c @subsubsubsection Extensible Service Types
  28931. The service type for an @emph{extensible} service looks like this:
  28932. @lisp
  28933. (define udev-service-type
  28934. (service-type (name 'udev)
  28935. (extensions
  28936. (list (service-extension shepherd-root-service-type
  28937. udev-shepherd-service)))
  28938. (compose concatenate) ;concatenate the list of rules
  28939. (extend (lambda (config rules)
  28940. (match config
  28941. (($ <udev-configuration> udev initial-rules)
  28942. (udev-configuration
  28943. (udev udev) ;the udev package to use
  28944. (rules (append initial-rules rules)))))))))
  28945. @end lisp
  28946. This is the service type for the
  28947. @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
  28948. management daemon}. Compared to the previous example, in addition to an
  28949. extension of @code{shepherd-root-service-type}, we see two new fields:
  28950. @table @code
  28951. @item compose
  28952. This is the procedure to @dfn{compose} the list of extensions to
  28953. services of this type.
  28954. Services can extend the udev service by passing it lists of rules; we
  28955. compose those extensions simply by concatenating them.
  28956. @item extend
  28957. This procedure defines how the value of the service is @dfn{extended} with
  28958. the composition of the extensions.
  28959. Udev extensions are composed into a list of rules, but the udev service
  28960. value is itself a @code{<udev-configuration>} record. So here, we
  28961. extend that record by appending the list of rules it contains to the
  28962. list of contributed rules.
  28963. @item description
  28964. This is a string giving an overview of the service type. The string can
  28965. contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
  28966. @command{guix system search} command searches these strings and displays
  28967. them (@pxref{Invoking guix system}).
  28968. @end table
  28969. There can be only one instance of an extensible service type such as
  28970. @code{udev-service-type}. If there were more, the
  28971. @code{service-extension} specifications would be ambiguous.
  28972. Still here? The next section provides a reference of the programming
  28973. interface for services.
  28974. @node Service Reference
  28975. @subsection Service Reference
  28976. We have seen an overview of service types (@pxref{Service Types and
  28977. Services}). This section provides a reference on how to manipulate
  28978. services and service types. This interface is provided by the
  28979. @code{(gnu services)} module.
  28980. @deffn {Scheme Procedure} service @var{type} [@var{value}]
  28981. Return a new service of @var{type}, a @code{<service-type>} object (see
  28982. below). @var{value} can be any object; it represents the parameters of
  28983. this particular service instance.
  28984. When @var{value} is omitted, the default value specified by @var{type}
  28985. is used; if @var{type} does not specify a default value, an error is
  28986. raised.
  28987. For instance, this:
  28988. @lisp
  28989. (service openssh-service-type)
  28990. @end lisp
  28991. @noindent
  28992. is equivalent to this:
  28993. @lisp
  28994. (service openssh-service-type
  28995. (openssh-configuration))
  28996. @end lisp
  28997. In both cases the result is an instance of @code{openssh-service-type}
  28998. with the default configuration.
  28999. @end deffn
  29000. @deffn {Scheme Procedure} service? @var{obj}
  29001. Return true if @var{obj} is a service.
  29002. @end deffn
  29003. @deffn {Scheme Procedure} service-kind @var{service}
  29004. Return the type of @var{service}---i.e., a @code{<service-type>} object.
  29005. @end deffn
  29006. @deffn {Scheme Procedure} service-value @var{service}
  29007. Return the value associated with @var{service}. It represents its
  29008. parameters.
  29009. @end deffn
  29010. Here is an example of how a service is created and manipulated:
  29011. @lisp
  29012. (define s
  29013. (service nginx-service-type
  29014. (nginx-configuration
  29015. (nginx nginx)
  29016. (log-directory log-directory)
  29017. (run-directory run-directory)
  29018. (file config-file))))
  29019. (service? s)
  29020. @result{} #t
  29021. (eq? (service-kind s) nginx-service-type)
  29022. @result{} #t
  29023. @end lisp
  29024. The @code{modify-services} form provides a handy way to change the
  29025. parameters of some of the services of a list such as
  29026. @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
  29027. evaluates to a list of services. Of course, you could always use
  29028. standard list combinators such as @code{map} and @code{fold} to do that
  29029. (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
  29030. @code{modify-services} simply provides a more concise form for this
  29031. common pattern.
  29032. @deffn {Scheme Syntax} modify-services @var{services} @
  29033. (@var{type} @var{variable} => @var{body}) @dots{}
  29034. Modify the services listed in @var{services} according to the given
  29035. clauses. Each clause has the form:
  29036. @example
  29037. (@var{type} @var{variable} => @var{body})
  29038. @end example
  29039. where @var{type} is a service type---e.g.,
  29040. @code{guix-service-type}---and @var{variable} is an identifier that is
  29041. bound within the @var{body} to the service parameters---e.g., a
  29042. @code{guix-configuration} instance---of the original service of that
  29043. @var{type}.
  29044. The @var{body} should evaluate to the new service parameters, which will
  29045. be used to configure the new service. This new service will replace the
  29046. original in the resulting list. Because a service's service parameters
  29047. are created using @code{define-record-type*}, you can write a succinct
  29048. @var{body} that evaluates to the new service parameters by using the
  29049. @code{inherit} feature that @code{define-record-type*} provides.
  29050. Clauses can also have the following form:
  29051. @lisp
  29052. (delete @var{type})
  29053. @end lisp
  29054. Such a clause removes all services of the given @var{type} from
  29055. @var{services}.
  29056. @xref{Using the Configuration System}, for example usage.
  29057. @end deffn
  29058. Next comes the programming interface for service types. This is
  29059. something you want to know when writing new service definitions, but not
  29060. necessarily when simply looking for ways to customize your
  29061. @code{operating-system} declaration.
  29062. @deftp {Data Type} service-type
  29063. @cindex service type
  29064. This is the representation of a @dfn{service type} (@pxref{Service Types
  29065. and Services}).
  29066. @table @asis
  29067. @item @code{name}
  29068. This is a symbol, used only to simplify inspection and debugging.
  29069. @item @code{extensions}
  29070. A non-empty list of @code{<service-extension>} objects (see below).
  29071. @item @code{compose} (default: @code{#f})
  29072. If this is @code{#f}, then the service type denotes services that cannot
  29073. be extended---i.e., services that do not receive ``values'' from other
  29074. services.
  29075. Otherwise, it must be a one-argument procedure. The procedure is called
  29076. by @code{fold-services} and is passed a list of values collected from
  29077. extensions. It may return any single value.
  29078. @item @code{extend} (default: @code{#f})
  29079. If this is @code{#f}, services of this type cannot be extended.
  29080. Otherwise, it must be a two-argument procedure: @code{fold-services}
  29081. calls it, passing it the initial value of the service as the first
  29082. argument and the result of applying @code{compose} to the extension
  29083. values as the second argument. It must return a value that is a valid
  29084. parameter value for the service instance.
  29085. @item @code{description}
  29086. This is a string, possibly using Texinfo markup, describing in a couple
  29087. of sentences what the service is about. This string allows users to
  29088. find about the service through @command{guix system search}
  29089. (@pxref{Invoking guix system}).
  29090. @item @code{default-value} (default: @code{&no-default-value})
  29091. The default value associated for instances of this service type. This
  29092. allows users to use the @code{service} form without its second argument:
  29093. @lisp
  29094. (service @var{type})
  29095. @end lisp
  29096. The returned service in this case has the default value specified by
  29097. @var{type}.
  29098. @end table
  29099. @xref{Service Types and Services}, for examples.
  29100. @end deftp
  29101. @deffn {Scheme Procedure} service-extension @var{target-type} @
  29102. @var{compute}
  29103. Return a new extension for services of type @var{target-type}.
  29104. @var{compute} must be a one-argument procedure: @code{fold-services}
  29105. calls it, passing it the value associated with the service that provides
  29106. the extension; it must return a valid value for the target service.
  29107. @end deffn
  29108. @deffn {Scheme Procedure} service-extension? @var{obj}
  29109. Return true if @var{obj} is a service extension.
  29110. @end deffn
  29111. Occasionally, you might want to simply extend an existing service. This
  29112. involves creating a new service type and specifying the extension of
  29113. interest, which can be verbose; the @code{simple-service} procedure
  29114. provides a shorthand for this.
  29115. @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
  29116. Return a service that extends @var{target} with @var{value}. This works
  29117. by creating a singleton service type @var{name}, of which the returned
  29118. service is an instance.
  29119. For example, this extends mcron (@pxref{Scheduled Job Execution}) with
  29120. an additional job:
  29121. @lisp
  29122. (simple-service 'my-mcron-job mcron-service-type
  29123. #~(job '(next-hour (3)) "guix gc -F 2G"))
  29124. @end lisp
  29125. @end deffn
  29126. At the core of the service abstraction lies the @code{fold-services}
  29127. procedure, which is responsible for ``compiling'' a list of services
  29128. down to a single directory that contains everything needed to boot and
  29129. run the system---the directory shown by the @command{guix system build}
  29130. command (@pxref{Invoking guix system}). In essence, it propagates
  29131. service extensions down the service graph, updating each node parameters
  29132. on the way, until it reaches the root node.
  29133. @deffn {Scheme Procedure} fold-services @var{services} @
  29134. [#:target-type @var{system-service-type}]
  29135. Fold @var{services} by propagating their extensions down to the root of
  29136. type @var{target-type}; return the root service adjusted accordingly.
  29137. @end deffn
  29138. Lastly, the @code{(gnu services)} module also defines several essential
  29139. service types, some of which are listed below.
  29140. @defvr {Scheme Variable} system-service-type
  29141. This is the root of the service graph. It produces the system directory
  29142. as returned by the @command{guix system build} command.
  29143. @end defvr
  29144. @defvr {Scheme Variable} boot-service-type
  29145. The type of the ``boot service'', which produces the @dfn{boot script}.
  29146. The boot script is what the initial RAM disk runs when booting.
  29147. @end defvr
  29148. @defvr {Scheme Variable} etc-service-type
  29149. The type of the @file{/etc} service. This service is used to create
  29150. files under @file{/etc} and can be extended by
  29151. passing it name/file tuples such as:
  29152. @lisp
  29153. (list `("issue" ,(plain-file "issue" "Welcome!\n")))
  29154. @end lisp
  29155. In this example, the effect would be to add an @file{/etc/issue} file
  29156. pointing to the given file.
  29157. @end defvr
  29158. @defvr {Scheme Variable} setuid-program-service-type
  29159. Type for the ``setuid-program service''. This service collects lists of
  29160. executable file names, passed as gexps, and adds them to the set of
  29161. setuid-root programs on the system (@pxref{Setuid Programs}).
  29162. @end defvr
  29163. @defvr {Scheme Variable} profile-service-type
  29164. Type of the service that populates the @dfn{system profile}---i.e., the
  29165. programs under @file{/run/current-system/profile}. Other services can
  29166. extend it by passing it lists of packages to add to the system profile.
  29167. @end defvr
  29168. @cindex provenance tracking, of the operating system
  29169. @anchor{provenance-service-type}
  29170. @defvr {Scheme Variable} provenance-service-type
  29171. This is the type of the service that records @dfn{provenance meta-data}
  29172. in the system itself. It creates several files under
  29173. @file{/run/current-system}:
  29174. @table @file
  29175. @item channels.scm
  29176. This is a ``channel file'' that can be passed to @command{guix pull -C}
  29177. or @command{guix time-machine -C}, and which describes the channels used
  29178. to build the system, if that information was available
  29179. (@pxref{Channels}).
  29180. @item configuration.scm
  29181. This is the file that was passed as the value for this
  29182. @code{provenance-service-type} service. By default, @command{guix
  29183. system reconfigure} automatically passes the OS configuration file it
  29184. received on the command line.
  29185. @item provenance
  29186. This contains the same information as the two other files but in a
  29187. format that is more readily processable.
  29188. @end table
  29189. In general, these two pieces of information (channels and configuration
  29190. file) are enough to reproduce the operating system ``from source''.
  29191. @quotation Caveats
  29192. This information is necessary to rebuild your operating system, but it
  29193. is not always sufficient. In particular, @file{configuration.scm}
  29194. itself is insufficient if it is not self-contained---if it refers to
  29195. external Guile modules or to extra files. If you want
  29196. @file{configuration.scm} to be self-contained, we recommend that modules
  29197. or files it refers to be part of a channel.
  29198. Besides, provenance meta-data is ``silent'' in the sense that it does
  29199. not change the bits contained in your system, @emph{except for the
  29200. meta-data bits themselves}. Two different OS configurations or sets of
  29201. channels can lead to the same system, bit-for-bit; when
  29202. @code{provenance-service-type} is used, these two systems will have
  29203. different meta-data and thus different store file names, which makes
  29204. comparison less trivial.
  29205. @end quotation
  29206. This service is automatically added to your operating system
  29207. configuration when you use @command{guix system reconfigure},
  29208. @command{guix system init}, or @command{guix deploy}.
  29209. @end defvr
  29210. @defvr {Scheme Variable} linux-loadable-module-service-type
  29211. Type of the service that collects lists of packages containing
  29212. kernel-loadable modules, and adds them to the set of kernel-loadable
  29213. modules.
  29214. This service type is intended to be extended by other service types,
  29215. such as below:
  29216. @lisp
  29217. (simple-service 'installing-module
  29218. linux-loadable-module-service-type
  29219. (list module-to-install-1
  29220. module-to-install-2))
  29221. @end lisp
  29222. This does not actually load modules at bootup, only adds it to the
  29223. kernel profile so that it @emph{can} be loaded by other means.
  29224. @end defvr
  29225. @node Shepherd Services
  29226. @subsection Shepherd Services
  29227. @cindex shepherd services
  29228. @cindex PID 1
  29229. @cindex init system
  29230. The @code{(gnu services shepherd)} module provides a way to define
  29231. services managed by the GNU@tie{}Shepherd, which is the
  29232. initialization system---the first process that is started when the
  29233. system boots, also known as PID@tie{}1
  29234. (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
  29235. Services in the Shepherd can depend on each other. For instance, the
  29236. SSH daemon may need to be started after the syslog daemon has been
  29237. started, which in turn can only happen once all the file systems have
  29238. been mounted. The simple operating system defined earlier (@pxref{Using
  29239. the Configuration System}) results in a service graph like this:
  29240. @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
  29241. You can actually generate such a graph for any operating system
  29242. definition using the @command{guix system shepherd-graph} command
  29243. (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
  29244. The @code{%shepherd-root-service} is a service object representing
  29245. PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
  29246. by passing it lists of @code{<shepherd-service>} objects.
  29247. @deftp {Data Type} shepherd-service
  29248. The data type representing a service managed by the Shepherd.
  29249. @table @asis
  29250. @item @code{provision}
  29251. This is a list of symbols denoting what the service provides.
  29252. These are the names that may be passed to @command{herd start},
  29253. @command{herd status}, and similar commands (@pxref{Invoking herd,,,
  29254. shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
  29255. @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
  29256. @item @code{requirement} (default: @code{'()})
  29257. List of symbols denoting the Shepherd services this one depends on.
  29258. @cindex one-shot services, for the Shepherd
  29259. @item @code{one-shot?} (default: @code{#f})
  29260. Whether this service is @dfn{one-shot}. One-shot services stop immediately
  29261. after their @code{start} action has completed. @xref{Slots of services,,,
  29262. shepherd, The GNU Shepherd Manual}, for more info.
  29263. @item @code{respawn?} (default: @code{#t})
  29264. Whether to restart the service when it stops, for instance when the
  29265. underlying process dies.
  29266. @item @code{start}
  29267. @itemx @code{stop} (default: @code{#~(const #f)})
  29268. The @code{start} and @code{stop} fields refer to the Shepherd's
  29269. facilities to start and stop processes (@pxref{Service De- and
  29270. Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
  29271. G-expressions that get expanded in the Shepherd configuration file
  29272. (@pxref{G-Expressions}).
  29273. @item @code{actions} (default: @code{'()})
  29274. @cindex actions, of Shepherd services
  29275. This is a list of @code{shepherd-action} objects (see below) defining
  29276. @dfn{actions} supported by the service, in addition to the standard
  29277. @code{start} and @code{stop} actions. Actions listed here become available as
  29278. @command{herd} sub-commands:
  29279. @example
  29280. herd @var{action} @var{service} [@var{arguments}@dots{}]
  29281. @end example
  29282. @item @code{auto-start?} (default: @code{#t})
  29283. Whether this service should be started automatically by the Shepherd. If it
  29284. is @code{#f} the service has to be started manually with @code{herd start}.
  29285. @item @code{documentation}
  29286. A documentation string, as shown when running:
  29287. @example
  29288. herd doc @var{service-name}
  29289. @end example
  29290. where @var{service-name} is one of the symbols in @code{provision}
  29291. (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
  29292. @item @code{modules} (default: @code{%default-modules})
  29293. This is the list of modules that must be in scope when @code{start} and
  29294. @code{stop} are evaluated.
  29295. @end table
  29296. @end deftp
  29297. The example below defines a Shepherd service that spawns
  29298. @command{syslogd}, the system logger from the GNU Networking Utilities
  29299. (@pxref{syslogd invocation, @command{syslogd},, inetutils, GNU
  29300. Inetutils}):
  29301. @example
  29302. (let ((config (plain-file "syslogd.conf" "@dots{}")))
  29303. (shepherd-service
  29304. (documentation "Run the syslog daemon (syslogd).")
  29305. (provision '(syslogd))
  29306. (requirement '(user-processes))
  29307. (start #~(make-forkexec-constructor
  29308. (list #$(file-append inetutils "/libexec/syslogd")
  29309. "--rcfile" #$config)
  29310. #:pid-file "/var/run/syslog.pid"))
  29311. (stop #~(make-kill-destructor))))
  29312. @end example
  29313. Key elements in this example are the @code{start} and @code{stop}
  29314. fields: they are @dfn{staged} code snippets that use the
  29315. @code{make-forkexec-constructor} procedure provided by the Shepherd and
  29316. its dual, @code{make-kill-destructor} (@pxref{Service De- and
  29317. Constructors,,, shepherd, The GNU Shepherd Manual}). The @code{start}
  29318. field will have @command{shepherd} spawn @command{syslogd} with the
  29319. given option; note that we pass @code{config} after @option{--rcfile},
  29320. which is a configuration file declared above (contents of this file are
  29321. omitted). Likewise, the @code{stop} field tells how this service is to
  29322. be stopped; in this case, it is stopped by making the @code{kill} system
  29323. call on its PID@. Code staging is achieved using G-expressions:
  29324. @code{#~} stages code, while @code{#$} ``escapes'' back to host code
  29325. (@pxref{G-Expressions}).
  29326. @deftp {Data Type} shepherd-action
  29327. This is the data type that defines additional actions implemented by a
  29328. Shepherd service (see above).
  29329. @table @code
  29330. @item name
  29331. Symbol naming the action.
  29332. @item documentation
  29333. This is a documentation string for the action. It can be viewed by running:
  29334. @example
  29335. herd doc @var{service} action @var{action}
  29336. @end example
  29337. @item procedure
  29338. This should be a gexp that evaluates to a procedure of at least one argument,
  29339. which is the ``running value'' of the service (@pxref{Slots of services,,,
  29340. shepherd, The GNU Shepherd Manual}).
  29341. @end table
  29342. The following example defines an action called @code{say-hello} that kindly
  29343. greets the user:
  29344. @lisp
  29345. (shepherd-action
  29346. (name 'say-hello)
  29347. (documentation "Say hi!")
  29348. (procedure #~(lambda (running . args)
  29349. (format #t "Hello, friend! arguments: ~s\n"
  29350. args)
  29351. #t)))
  29352. @end lisp
  29353. Assuming this action is added to the @code{example} service, then you can do:
  29354. @example
  29355. # herd say-hello example
  29356. Hello, friend! arguments: ()
  29357. # herd say-hello example a b c
  29358. Hello, friend! arguments: ("a" "b" "c")
  29359. @end example
  29360. This, as you can see, is a fairly sophisticated way to say hello.
  29361. @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
  29362. info on actions.
  29363. @end deftp
  29364. @defvr {Scheme Variable} shepherd-root-service-type
  29365. The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
  29366. This is the service type that extensions target when they want to create
  29367. shepherd services (@pxref{Service Types and Services}, for an example).
  29368. Each extension must pass a list of @code{<shepherd-service>}. Its
  29369. value must be a @code{shepherd-configuration}, as described below.
  29370. @end defvr
  29371. @deftp {Data Type} shepherd-configuration
  29372. This data type represents the Shepherd's configuration.
  29373. @table @code
  29374. @item shepherd (default: @code{shepherd})
  29375. The Shepherd package to use.
  29376. @item services (default: @code{'()})
  29377. A list of @code{<shepherd-service>} to start.
  29378. You should probably use the service extension
  29379. mechanism instead (@pxref{Shepherd Services}).
  29380. @end table
  29381. @end deftp
  29382. The following example specifies the Shepherd package for the operating
  29383. system:
  29384. @lisp
  29385. (operating-system
  29386. ;; ...
  29387. (services (append (list openssh-service-type))
  29388. ;; ...
  29389. %desktop-services)
  29390. ;; ...
  29391. ;; Use own Shepherd package.
  29392. (essential-services
  29393. (modify-services (operating-system-default-essential-services
  29394. this-operating-system)
  29395. (shepherd-root-service-type config => (shepherd-configuration
  29396. (inherit config)
  29397. (shepherd my-shepherd))))))
  29398. @end lisp
  29399. @defvr {Scheme Variable} %shepherd-root-service
  29400. This service represents PID@tie{}1.
  29401. @end defvr
  29402. @node Complex Configurations
  29403. @subsection Complex Configurations
  29404. @cindex complex configurations
  29405. Some programs might have rather complex configuration files or formats,
  29406. and to make it easier to create Scheme bindings for these configuration
  29407. files, you can use the utilities defined in the @code{(gnu services
  29408. configuration)} module.
  29409. The main utility is the @code{define-configuration} macro, which you
  29410. will use to define a Scheme record type (@pxref{Record Overview,,,
  29411. guile, GNU Guile Reference Manual}). The Scheme record will be
  29412. serialized to a configuration file by using @dfn{serializers}, which are
  29413. procedures that take some kind of Scheme value and returns a
  29414. G-expression (@pxref{G-Expressions}), which should, once serialized to
  29415. the disk, return a string. More details are listed below.
  29416. @deffn {Scheme Syntax} define-configuration @var{name} @var{clause1} @
  29417. @var{clause2} ...
  29418. Create a record type named @code{@var{name}} that contains the
  29419. fields found in the clauses.
  29420. A clause can have one of the following forms:
  29421. @example
  29422. (@var{field-name}
  29423. (@var{type} @var{default-value})
  29424. @var{documentation})
  29425. (@var{field-name}
  29426. (@var{type} @var{default-value})
  29427. @var{documentation}
  29428. @var{serializer})
  29429. (@var{field-name}
  29430. (@var{type})
  29431. @var{documentation})
  29432. (@var{field-name}
  29433. (@var{type})
  29434. @var{documentation}
  29435. @var{serializer})
  29436. @end example
  29437. @var{field-name} is an identifier that denotes the name of the field in
  29438. the generated record.
  29439. @var{type} is the type of the value corresponding to @var{field-name};
  29440. since Guile is untyped, a predicate
  29441. procedure---@code{@var{type}?}---will be called on the value
  29442. corresponding to the field to ensure that the value is of the correct
  29443. type. This means that if say, @var{type} is @code{package}, then a
  29444. procedure named @code{package?} will be applied on the value to make
  29445. sure that it is indeed a @code{<package>} object.
  29446. @var{default-value} is the default value corresponding to the field; if
  29447. none is specified, the user is forced to provide a value when creating
  29448. an object of the record type.
  29449. @c XXX: Should these be full sentences or are they allow to be very
  29450. @c short like package synopses?
  29451. @var{documentation} is a string formatted with Texinfo syntax which
  29452. should provide a description of what setting this field does.
  29453. @var{serializer} is the name of a procedure which takes two arguments,
  29454. the first is the name of the field, and the second is the value
  29455. corresponding to the field. The procedure should return a string or
  29456. G-expression (@pxref{G-Expressions}) that represents the content that
  29457. will be serialized to the configuration file. If none is specified, a
  29458. procedure of the name @code{serialize-@var{type}} will be used.
  29459. A simple serializer procedure could look like this:
  29460. @lisp
  29461. (define (serialize-boolean field-name value)
  29462. (let ((value (if value "true" "false")))
  29463. #~(string-append #$field-name #$value)))
  29464. @end lisp
  29465. In some cases multiple different configuration records might be defined
  29466. in the same file, but their serializers for the same type might have to
  29467. be different, because they have different configuration formats. For
  29468. example, the @code{serialize-boolean} procedure for the Getmail service
  29469. would have to be different for the one for the Transmission service. To
  29470. make it easier to deal with this situation, one can specify a serializer
  29471. prefix by using the @code{prefix} literal in the
  29472. @code{define-configuration} form. This means that one doesn't have to
  29473. manually specify a custom @var{serializer} for every field.
  29474. @lisp
  29475. (define (foo-serialize-string field-name value)
  29476. @dots{})
  29477. (define (bar-serialize-string field-name value)
  29478. @dots{})
  29479. (define-configuration foo-configuration
  29480. (label
  29481. (string)
  29482. "The name of label.")
  29483. (prefix foo-))
  29484. (define-configuration bar-configuration
  29485. (ip-address
  29486. (string)
  29487. "The IPv4 address for this device.")
  29488. (prefix bar-))
  29489. @end lisp
  29490. However, in some cases you might not want to serialize any of the values
  29491. of the record, to do this, you can use the @code{no-serialization}
  29492. literal. There is also the @code{define-configuration/no-serialization}
  29493. macro which is a shorthand of this.
  29494. @lisp
  29495. ;; Nothing will be serialized to disk.
  29496. (define-configuration foo-configuration
  29497. (field
  29498. (string "test")
  29499. "Some documentation.")
  29500. (no-serialization))
  29501. ;; The same thing as above.
  29502. (define-configuration/no-serialization bar-configuration
  29503. (field
  29504. (string "test")
  29505. "Some documentation."))
  29506. @end lisp
  29507. @end deffn
  29508. @deffn {Scheme Syntax} define-maybe @var{type}
  29509. Sometimes a field should not be serialized if the user doesn’t specify a
  29510. value. To achieve this, you can use the @code{define-maybe} macro to
  29511. define a ``maybe type''; if the value of a maybe type is set to the
  29512. @code{disabled}, it will not be serialized.
  29513. When defining a ``maybe type'', the corresponding serializer for the
  29514. regular type will be used by default. For example, a field of type
  29515. @code{maybe-string} will be serialized using the @code{serialize-string}
  29516. procedure by default, you can of course change this by specifying a
  29517. custom serializer procedure. Likewise, the type of the value would have
  29518. to be a string, unless it is set to the @code{disabled} symbol.
  29519. @lisp
  29520. (define-maybe string)
  29521. (define (serialize-string field-name value)
  29522. @dots{})
  29523. (define-configuration baz-configuration
  29524. (name
  29525. ;; Nothing will be serialized by default. If set to a string, the
  29526. ;; `serialize-string' procedure will be used to serialize the string.
  29527. (maybe-string 'disabled)
  29528. "The name of this module."))
  29529. @end lisp
  29530. Like with @code{define-configuration}, one can set a prefix for the
  29531. serializer name by using the @code{prefix} literal.
  29532. @lisp
  29533. (define-maybe integer
  29534. (prefix baz-))
  29535. (define (baz-serialize-interger field-name value)
  29536. @dots{})
  29537. @end lisp
  29538. There is also the @code{no-serialization} literal, which when set means
  29539. that no serializer will be defined for the ``maybe type'', regardless of
  29540. its value is @code{disabled} or not.
  29541. @code{define-maybe/no-serialization} is a shorthand for specifying the
  29542. @code{no-serialization} literal.
  29543. @lisp
  29544. (define-maybe/no-serialization symbol)
  29545. (define-configuration/no-serialization test-configuration
  29546. (mode
  29547. (maybe-symbol 'disabled)
  29548. "Docstring."))
  29549. @end lisp
  29550. @end deffn
  29551. @deffn {Scheme Procedure} serialize-configuration @var{configuration} @
  29552. @var{fields}
  29553. Return a G-expression that contains the values corresponding to the
  29554. @var{fields} of @var{configuration}, a record that has been generated by
  29555. @code{define-configuration}. The G-expression can then be serialized to
  29556. disk by using something like @code{mixed-text-file}.
  29557. @end deffn
  29558. @deffn {Scheme Procedure} validate-configuration @var{configuration}
  29559. @var{fields}
  29560. Type-check @var{fields}, a list of field names of @var{configuration}, a
  29561. configuration record created by @code{define-configuration}.
  29562. @end deffn
  29563. @deffn {Scheme Procedure} empty-serializer @var{field-name} @var{value}
  29564. A serializer that just returns an empty string. The
  29565. @code{serialize-package} procedure is an alias for this.
  29566. @end deffn
  29567. Once you have defined a configuration record, you will most likely also
  29568. want to document it so that other people know to use it. To help with
  29569. that, there are two procedures, both of which are documented below.
  29570. @deffn {Scheme Procedure} generate-documentation @var{documentation} @
  29571. @var{documentation-name}
  29572. Generate a Texinfo fragment from the docstrings in @var{documentation},
  29573. a list of @code{(@var{label} @var{fields} @var{sub-documentation} ...)}.
  29574. @var{label} should be a symbol and should be the name of the
  29575. configuration record. @var{fields} should be a list of all the fields
  29576. available for the configuration record.
  29577. @var{sub-documentation} is a @code{(@var{field-name}
  29578. @var{configuration-name})} tuple. @var{field-name} is the name of the
  29579. field which takes another configuration record as its value, and
  29580. @var{configuration-name} is the name of that configuration record.
  29581. @var{sub-documentation} is only needed if there are nested configuration
  29582. records. For example, the @code{getmail-configuration} record
  29583. (@pxref{Mail Services}) accepts a @code{getmail-configuration-file}
  29584. record in one of its @code{rcfile} field, therefore documentation for
  29585. @code{getmail-configuration-file} is nested in
  29586. @code{getmail-configuration}.
  29587. @lisp
  29588. (generate-documentation
  29589. `((getmail-configuration ,getmail-configuration-fields
  29590. (rcfile getmail-configuration-file))
  29591. @dots{})
  29592. 'getmail-configuration)
  29593. @end lisp
  29594. @var{documentation-name} should be a symbol and should be the name of
  29595. the configuration record.
  29596. @end deffn
  29597. @deffn {Scheme Procedure} configuration->documentation
  29598. @var{configuration-symbol}
  29599. Take @var{configuration-symbol}, the symbol corresponding to the name
  29600. used when defining a configuration record with
  29601. @code{define-configuration}, and print the Texinfo documentation of its
  29602. fields. This is useful if there aren’t any nested configuration records
  29603. since it only prints the documentation for the top-level fields.
  29604. @end deffn
  29605. As of right now, there is no automated way to generate documentation for
  29606. configuration records and put them in the manual. Instead, every
  29607. time you make a change to the docstrings of a configuration record, you
  29608. have to manually call @code{generate-documentation} or
  29609. @code{configuration->documentation}, and paste the output into the
  29610. @file{doc/guix.texi} file.
  29611. @c TODO: Actually test this
  29612. Below is an example of a record type created using
  29613. @code{define-configuration} and friends.
  29614. @lisp
  29615. (use-modules (gnu services)
  29616. (guix gexp)
  29617. (gnu services configuration)
  29618. (srfi srfi-26)
  29619. (srfi srfi-1))
  29620. ;; Turn field names, which are Scheme symbols into strings
  29621. (define (uglify-field-name field-name)
  29622. (let ((str (symbol->string field-name)))
  29623. ;; field? -> is-field
  29624. (if (string-suffix? "?" str)
  29625. (string-append "is-" (string-drop-right str 1))
  29626. str)))
  29627. (define (serialize-string field-name value)
  29628. #~(string-append #$(uglify-field-name field-name) " = " #$value "\n"))
  29629. (define (serialize-integer field-name value)
  29630. (serialize-string field-name (number->string value)))
  29631. (define (serialize-boolean field-name value)
  29632. (serialize-string field-name (if value "true" "false")))
  29633. (define (serialize-contact-name field-name value)
  29634. #~(string-append "\n[" #$value "]\n"))
  29635. (define (list-of-contact-configurations? lst)
  29636. (every contact-configuration? lst))
  29637. (define (serialize-list-of-contact-configurations field-name value)
  29638. #~(string-append #$@@(map (cut serialize-configuration <>
  29639. contact-configuration-fields)
  29640. value)))
  29641. (define (serialize-contacts-list-configuration configuration)
  29642. (mixed-text-file
  29643. "contactrc"
  29644. #~(string-append "[Owner]\n"
  29645. #$(serialize-configuration
  29646. configuration contacts-list-configuration-fields))))
  29647. (define-maybe integer)
  29648. (define-maybe string)
  29649. (define-configuration contact-configuration
  29650. (name
  29651. (string)
  29652. "The name of the contact."
  29653. serialize-contact-name)
  29654. (phone-number
  29655. (maybe-integer 'disabled)
  29656. "The person's phone number.")
  29657. (email
  29658. (maybe-string 'disabled)
  29659. "The person's email address.")
  29660. (married?
  29661. (boolean)
  29662. "Whether the person is married."))
  29663. (define-configuration contacts-list-configuration
  29664. (name
  29665. (string)
  29666. "The name of the owner of this contact list.")
  29667. (email
  29668. (string)
  29669. "The owner's email address.")
  29670. (contacts
  29671. (list-of-contact-configurations '())
  29672. "A list of @@code@{contact-configuation@} records which contain
  29673. information about all your contacts."))
  29674. @end lisp
  29675. A contacts list configuration could then be created like this:
  29676. @lisp
  29677. (define my-contacts
  29678. (contacts-list-configuration
  29679. (name "Alice")
  29680. (email "alice@@example.org")
  29681. (contacts
  29682. (list (contact-configuration
  29683. (name "Bob")
  29684. (phone-number 1234)
  29685. (email "bob@@gnu.org")
  29686. (married? #f))
  29687. (contact-configuration
  29688. (name "Charlie")
  29689. (phone-number 0000)
  29690. (married? #t))))))
  29691. @end lisp
  29692. After serializing the configuration to disk, the resulting file would
  29693. look like this:
  29694. @example
  29695. [owner]
  29696. name = Alice
  29697. email = alice@@example.org
  29698. [Bob]
  29699. phone-number = 1234
  29700. email = bob@@gnu.org
  29701. is-married = false
  29702. [Charlie]
  29703. phone-number = 0
  29704. is-married = true
  29705. @end example
  29706. @node Home Configuration
  29707. @chapter Home Configuration
  29708. @cindex home configuration
  29709. Guix supports declarative configuration of @dfn{home environments} by
  29710. utilizing the configuration mechanism described in the previous chapter
  29711. (@pxref{Defining Services}), but for user's dotfiles and packages. It
  29712. works both on Guix System and foreign distros and allows users to
  29713. declare all the packages and services that should be installed and
  29714. configured for the user. Once a user has written a file containing
  29715. @code{home-environment} record, such a configuration can be
  29716. @dfn{instantiated} by an unprivileged user with the @command{guix home}
  29717. command (@pxref{Invoking guix home}).
  29718. @c Maybe later, it will be possible to make home configuration a part of
  29719. @c system configuration to make everything managed by guix system.
  29720. @quotation Note
  29721. The functionality described in this section is still under development
  29722. and is subject to change. Get in touch with us on
  29723. @email{guix-devel@@gnu.org}!
  29724. @end quotation
  29725. The user's home environment usually consists of three basic parts:
  29726. software, configuration, and state. Software in mainstream distros are
  29727. usually installed system-wide, but with GNU Guix most software packages
  29728. can be installed on a per-user basis without needing root privileges,
  29729. and are thus considered part of the user’s @dfn{home environment}.
  29730. Packages on their own not very useful in many cases, because often they
  29731. require some additional configuration, usually config files that reside
  29732. in @env{XDG_CONFIG_HOME} (@file{~/.config} by default) or other
  29733. directories. Everything else can be considered state, like media files,
  29734. application databases, and logs.
  29735. Using Guix for managing home environments provides a number of
  29736. advantages:
  29737. @itemize
  29738. @item All software can be configured in one language (Guile Scheme),
  29739. this gives users the ability to share values between configurations of
  29740. different programs.
  29741. @item A well-defined home environment is self-contained and can be
  29742. created in a declarative and reproducible way---there is no need to grab
  29743. external binaries or manually edit some configuration file.
  29744. @item After every @command{guix home reconfigure} invocation, a new home
  29745. environment generation will be created. This means that users can
  29746. rollback to a previous home environment generation so they don’t have to
  29747. worry about breaking their configuration.
  29748. @item It is possible to manage stateful data with Guix Home, this
  29749. includes the ability to automatically clone Git repositories on the
  29750. initial setup of the machine, and periodically running commands like
  29751. @command{rsync} to sync data with another host. This functionality is
  29752. still in an experimental stage, though.
  29753. @end itemize
  29754. @menu
  29755. * Declaring the Home Environment:: Customizing your Home.
  29756. * Configuring the Shell:: Enabling home environment.
  29757. * Home Services:: Specifying home services.
  29758. * Invoking guix home:: Instantiating a home configuration.
  29759. @end menu
  29760. @node Declaring the Home Environment
  29761. @section Declaring the Home Environment
  29762. The home environment is configured by providing a
  29763. @code{home-environment} declaration in a file that can be passed to the
  29764. @command{guix home} command (@pxref{Invoking guix home}). The easiest
  29765. way to get started is by generating an initial configuration with
  29766. @command{guix home import}:
  29767. @example
  29768. guix home import ~/src/guix-config
  29769. @end example
  29770. The @command{guix home import} command reads some of the ``dot files''
  29771. such as @file{~/.bashrc} found in your home directory and copies them to
  29772. the given directory, @file{~/src/guix-config} in this case; it also
  29773. reads the contents of your profile, @file{~/.guix-profile}, and, based
  29774. on that, it populates @file{~/src/guix-config/home-configuration.scm}
  29775. with a Home configuration that resembles your current configuration.
  29776. A simple setup can include Bash and a custom text configuration, like in
  29777. the example below. Don't be afraid to declare home environment parts,
  29778. which overlaps with your current dot files: before installing any
  29779. configuration files, Guix Home will back up existing config files to a
  29780. separate place in the home directory.
  29781. @quotation Note
  29782. It is highly recommended that you manage your shell or shells with Guix
  29783. Home, because it will make sure that all the necessary scripts are
  29784. sourced by the shell configuration file. Otherwise you will need to do
  29785. it manually. (@pxref{Configuring the Shell}).
  29786. @end quotation
  29787. @findex home-environment
  29788. @lisp
  29789. @include he-config-bare-bones.scm
  29790. @end lisp
  29791. The @code{packages} field should be self-explanatory, it will install
  29792. the list of packages into the user's profile. The most important field
  29793. is @code{services}, it contains a list of @dfn{home services}, which are
  29794. the basic building blocks of a home environment.
  29795. There is no daemon (at least not necessarily) related to a home service,
  29796. a home service is just an element that is used to declare part of home
  29797. environment and extend other parts of it. The extension mechanism
  29798. discussed in the previous chapter (@pxref{Defining Services}) should not
  29799. be confused with Shepherd services (@pxref{Shepherd Services}). Using this extension
  29800. mechanism and some Scheme code that glues things together gives the user
  29801. the freedom to declare their own, very custom, home environments.
  29802. @cindex container, for @command{guix home}
  29803. Once the configuration looks good, you can first test it in a throw-away
  29804. ``container'':
  29805. @example
  29806. guix home container config.scm
  29807. @end example
  29808. The command above spawns a shell where your home environment is running.
  29809. The shell runs in a container, meaning it's isolated from the rest of
  29810. the system, so it's a good way to try out your configuration---you can
  29811. see if configuration bits are missing or misbehaving, if daemons get
  29812. started, and so on. Once you exit that shell, you're back to the prompt
  29813. of your original shell ``in the real world''.
  29814. Once you have a configuration file that suits your needs, you can
  29815. reconfigure your home by running:
  29816. @example
  29817. guix home reconfigure config.scm
  29818. @end example
  29819. This ``builds'' your home environment and creates @file{~/.guix-home}
  29820. pointing to it. Voilà!
  29821. @quotation Note
  29822. Make sure the operating system has elogind, systemd, or a similar
  29823. mechanism to create the XDG run-time directory and has the
  29824. @env{XDG_RUNTIME_DIR} variable set. Failing that, the
  29825. @file{on-first-login} script will not execute anything, and processes
  29826. like user Shepherd and its descendants will not start.
  29827. @end quotation
  29828. @node Configuring the Shell
  29829. @section Configuring the Shell
  29830. This section is safe to skip if your shell or shells are managed by
  29831. Guix Home. Otherwise, read it carefully.
  29832. There are a few scripts that must be evaluated by a login shell to
  29833. activate the home environment. The shell startup files only read by
  29834. login shells often have @code{profile} suffix. For more information
  29835. about login shells see @ref{Invoking Bash,,, bash, The GNU Bash
  29836. Reference Manual} and see @ref{Bash Startup Files,,, bash, The GNU Bash
  29837. Reference Manual}.
  29838. The first script that needs to be sourced is @file{setup-environment},
  29839. which sets all the necessary environment variables (including variables
  29840. declared by the user) and the second one is @file{on-first-login}, which
  29841. starts Shepherd for the current user and performs actions declared by
  29842. other home services that extends
  29843. @code{home-run-on-first-login-service-type}.
  29844. Guix Home will always create @file{~/.profile}, which contains the
  29845. following lines:
  29846. @example
  29847. HOME_ENVIRONMENT=$HOME/.guix-home
  29848. . $HOME_ENVIRONMENT/setup-environment
  29849. $HOME_ENVIRONMENT/on-first-login
  29850. @end example
  29851. This makes POSIX compliant login shells activate the home environment.
  29852. However, in most cases this file won't be read by most modern shells,
  29853. because they are run in non POSIX mode by default and have their own
  29854. @file{*profile} startup files. For example Bash will prefer
  29855. @file{~/.bash_profile} in case it exists and only if it doesn't will it
  29856. fallback to @file{~/.profile}. Zsh (if no additional options are
  29857. specified) will ignore @file{~/.profile}, even if @file{~/.zprofile}
  29858. doesn't exist.
  29859. To make your shell respect @file{~/.profile}, add @code{. ~/.profile} or
  29860. @code{source ~/profile} to the startup file for the login shell. In
  29861. case of Bash, it is @file{~/.bash_profile}, and in case of Zsh, it is
  29862. @file{~/.zprofile}.
  29863. @quotation Note
  29864. This step is only required if your shell is NOT managed by Guix Home.
  29865. Otherwise, everything will be done automatically.
  29866. @end quotation
  29867. @node Home Services
  29868. @section Home Services
  29869. @cindex home services
  29870. A @dfn{home service} is not necessarily something that has a daemon and
  29871. is managed by Shepherd (@pxref{Jump Start,,, shepherd, The GNU Shepherd
  29872. Manual}), in most cases it doesn't. It's a simple building block of the
  29873. home environment, often declaring a set of packages to be installed in
  29874. the home environment profile, a set of config files to be symlinked into
  29875. @env{XDG_CONFIG_HOME} (@file{~/.config} by default), and environment
  29876. variables to be set by a login shell.
  29877. There is a service extension mechanism (@pxref{Service Composition})
  29878. which allows home services to extend other home services and utilize
  29879. capabilities they provide; for example: declare mcron jobs
  29880. (@pxref{Top,,, mcron, GNU@tie{}Mcron}) by extending @ref{Mcron Home
  29881. Service}; declare daemons by extending @ref{Shepherd Home Service}; add
  29882. commands, which will be invoked on by the Bash by extending
  29883. @ref{Shells Home Services, @code{home-bash-service-type}}.
  29884. A good way to discover available home services is using the
  29885. @command{guix home search} command (@pxref{Invoking guix home}). After
  29886. the required home services are found, include its module with the
  29887. @code{use-modules} form (@pxref{use-modules,, Using Guile Modules,
  29888. guile, The GNU Guile Reference Manual}), or the @code{#:use-modules}
  29889. directive (@pxref{define-module,, Creating Guile Modules, guile, The GNU
  29890. Guile Reference Manual}) and declare a home service using the
  29891. @code{service} function, or extend a service type by declaring a new
  29892. service with the @code{simple-service} procedure from @code{(gnu
  29893. services)}.
  29894. @menu
  29895. * Essential Home Services:: Environment variables, packages, on-* scripts.
  29896. * Shells: Shells Home Services. POSIX shells, Bash, Zsh.
  29897. * Mcron: Mcron Home Service. Scheduled User's Job Execution.
  29898. * Shepherd: Shepherd Home Service. Managing User's Daemons.
  29899. * Desktop: Desktop Home Services. Services for graphical environments.
  29900. @end menu
  29901. @c In addition to that Home Services can provide
  29902. @node Essential Home Services
  29903. @subsection Essential Home Services
  29904. There are a few essential home services defined in
  29905. @code{(gnu services)}, they are mostly for internal use and are required
  29906. to build a home environment, but some of them will be useful for the end
  29907. user.
  29908. @cindex environment variables
  29909. @defvr {Scheme Variable} home-environment-variables-service-type
  29910. The service of this type will be instantiated by every home environment
  29911. automatically by default, there is no need to define it, but someone may
  29912. want to extend it with a list of pairs to set some environment
  29913. variables.
  29914. @lisp
  29915. (list ("ENV_VAR1" . "value1")
  29916. ("ENV_VAR2" . "value2"))
  29917. @end lisp
  29918. The easiest way to extend a service type, without defining a new service
  29919. type is to use the @code{simple-service} helper from @code{(gnu
  29920. services)}.
  29921. @lisp
  29922. (simple-service 'some-useful-env-vars-service
  29923. home-environment-variables-service-type
  29924. `(("LESSHISTFILE" . "$XDG_CACHE_HOME/.lesshst")
  29925. ("SHELL" . ,(file-append zsh "/bin/zsh"))
  29926. ("USELESS_VAR" . #f)
  29927. ("_JAVA_AWT_WM_NONREPARENTING" . #t)))
  29928. @end lisp
  29929. If you include such a service in you home environment definition, it
  29930. will add the following content to the @file{setup-environment} script
  29931. (which is expected to be sourced by the login shell):
  29932. @example
  29933. export LESSHISTFILE=$XDG_CACHE_HOME/.lesshst
  29934. export SHELL=/gnu/store/2hsg15n644f0glrcbkb1kqknmmqdar03-zsh-5.8/bin/zsh
  29935. export _JAVA_AWT_WM_NONREPARENTING
  29936. @end example
  29937. @quotation Note
  29938. Make sure that module @code{(gnu packages shells)} is imported with
  29939. @code{use-modules} or any other way, this namespace contains the
  29940. definition of the @code{zsh} packages, which is used in the example
  29941. above.
  29942. @end quotation
  29943. The association list (@pxref{Association Lists, alists, Association
  29944. Lists, guile, The GNU Guile Reference manual}) is a data structure
  29945. containing key-value pairs, for
  29946. @code{home-environment-variables-service-type} the key is always a
  29947. string, the value can be a string, string-valued gexp
  29948. (@pxref{G-Expressions}), file-like object (@pxref{G-Expressions,
  29949. file-like object}) or boolean. For gexps, the variable will be set to
  29950. the value of the gexp; for file-like objects, it will be set to the path
  29951. of the file in the store (@pxref{The Store}); for @code{#t}, it will
  29952. export the variable without any value; and for @code{#f}, it will omit
  29953. variable.
  29954. @end defvr
  29955. @defvr {Scheme Variable} home-profile-service-type
  29956. The service of this type will be instantiated by every home environment
  29957. automatically, there is no need to define it, but you may want to extend
  29958. it with a list of packages if you want to install additional packages
  29959. into your profile. Other services, which need to make some programs
  29960. available to the user will also extend this service type.
  29961. The extension value is just a list of packages:
  29962. @lisp
  29963. (list htop vim emacs)
  29964. @end lisp
  29965. The same approach as @code{simple-service} (@pxref{Service Reference,
  29966. simple-service}) for @code{home-environment-variables-service-type} can
  29967. be used here, too. Make sure that modules containing the specified
  29968. packages are imported with @code{use-modules}. To find a package or
  29969. information about its module use @command{guix search} (@pxref{Invoking
  29970. guix package}). Alternatively, @code{specification->package} can be
  29971. used to get the package record from string without importing related
  29972. module.
  29973. @end defvr
  29974. There are few more essential services, but users are not expected to
  29975. extend them.
  29976. @defvr {Scheme Variable} home-service-type
  29977. The root of home services DAG, it generates a folder, which later will be
  29978. symlinked to @file{~/.guix-home}, it contains configurations,
  29979. profile with binaries and libraries, and some necessary scripts to glue
  29980. things together.
  29981. @end defvr
  29982. @defvr {Scheme Variable} home-run-on-first-login-service-type
  29983. The service of this type generates a Guile script, which is expected to
  29984. be executed by the login shell. It is only executed if the special flag
  29985. file inside @env{XDG_RUNTIME_DIR} hasn't been created, this prevents
  29986. redundant executions of the script if multiple login shells are spawned.
  29987. It can be extended with a gexp. However, to autostart an application,
  29988. users @emph{should not} use this service, in most cases it's better to extend
  29989. @code{home-shepherd-service-type} with a Shepherd service
  29990. (@pxref{Shepherd Services}), or extend the shell's startup file with
  29991. the required command using the appropriate service type.
  29992. @end defvr
  29993. @defvr {Scheme Variable} home-activation-service-type
  29994. The service of this type generates a guile script, which runs on every
  29995. @command{guix home reconfigure} invocation or any other action, which
  29996. leads to the activation of the home environment.
  29997. @end defvr
  29998. @node Shells Home Services
  29999. @subsection Shells
  30000. @cindex shell
  30001. @cindex login shell
  30002. @cindex interactive shell
  30003. @cindex bash
  30004. @cindex zsh
  30005. Shells play a quite important role in the environment initialization
  30006. process, you can configure them manually as described in section
  30007. @ref{Configuring the Shell}, but the recommended way is to use home services
  30008. listed below. It's both easier and more reliable.
  30009. Each home environment instantiates
  30010. @code{home-shell-profile-service-type}, which creates a
  30011. @file{~/.profile} startup file for all POSIX-compatible shells. This
  30012. file contains all the necessary steps to properly initialize the
  30013. environment, but many modern shells like Bash or Zsh prefer their own
  30014. startup files, that's why the respective home services
  30015. (@code{home-bash-service-type} and @code{home-zsh-service-type}) ensure
  30016. that @file{~/.profile} is sourced by @file{~/.bash_profile} and
  30017. @file{~/.zprofile}, respectively.
  30018. @subsubheading Shell Profile Service
  30019. @deftp {Data Type} home-shell-profile-configuration
  30020. Available @code{home-shell-profile-configuration} fields are:
  30021. @table @asis
  30022. @item @code{profile} (default: @code{()}) (type: text-config)
  30023. @code{home-shell-profile} is instantiated automatically by
  30024. @code{home-environment}, DO NOT create this service manually, it can
  30025. only be extended. @code{profile} is a list of file-like objects, which
  30026. will go to @file{~/.profile}. By default @file{~/.profile} contains the
  30027. initialization code which must be evaluated by the login shell to make
  30028. home-environment's profile available to the user, but other commands can
  30029. be added to the file if it is really necessary. In most cases shell's
  30030. configuration files are preferred places for user's customizations.
  30031. Extend home-shell-profile service only if you really know what you do.
  30032. @end table
  30033. @end deftp
  30034. @subsubheading Bash Home Service
  30035. @anchor{home-bash-configuration}
  30036. @deftp {Data Type} home-bash-configuration
  30037. Available @code{home-bash-configuration} fields are:
  30038. @table @asis
  30039. @item @code{package} (default: @code{bash}) (type: package)
  30040. The Bash package to use.
  30041. @item @code{guix-defaults?} (default: @code{#t}) (type: boolean)
  30042. Add sane defaults like reading @file{/etc/bashrc} and coloring the output of
  30043. @command{ls} to the top of the @file{.bashrc} file.
  30044. @item @code{environment-variables} (default: @code{()}) (type: alist)
  30045. Association list of environment variables to set for the Bash session. The
  30046. rules for the @code{home-environment-variables-service-type} apply
  30047. here (@pxref{Essential Home Services}). The contents of this field will be
  30048. added after the contents of the @code{bash-profile} field.
  30049. @item @code{aliases} (default: @code{()}) (type: alist)
  30050. Association list of aliases to set for the Bash session. The aliases
  30051. will be defined after the contents of the @code{bashrc} field has been
  30052. put in the @file{.bashrc} file. The alias will automatically be quoted,
  30053. so something line this:
  30054. @lisp
  30055. '(("ls" . "ls -alF"))
  30056. @end lisp
  30057. turns into
  30058. @example
  30059. alias ls="ls -alF"
  30060. @end example
  30061. @item @code{bash-profile} (default: @code{()}) (type: text-config)
  30062. List of file-like objects, which will be added to @file{.bash_profile}.
  30063. Used for executing user's commands at start of login shell (In most
  30064. cases the shell started on tty just after login). @file{.bash_login}
  30065. won't be ever read, because @file{.bash_profile} always present.
  30066. @item @code{bashrc} (default: @code{()}) (type: text-config)
  30067. List of file-like objects, which will be added to @file{.bashrc}. Used
  30068. for executing user's commands at start of interactive shell (The shell
  30069. for interactive usage started by typing @code{bash} or by terminal app
  30070. or any other program).
  30071. @item @code{bash-logout} (default: @code{()}) (type: text-config)
  30072. List of file-like objects, which will be added to @file{.bash_logout}.
  30073. Used for executing user's commands at the exit of login shell. It won't
  30074. be read in some cases (if the shell terminates by exec'ing another
  30075. process for example).
  30076. @end table
  30077. @end deftp
  30078. You can extend the Bash service by using the @code{home-bash-extension}
  30079. configuration record, whose fields most mirror that of
  30080. @code{home-bash-configuration} (@pxref{home-bash-configuration}). The
  30081. contents of the extensions will be added to the end of the corresponding
  30082. Bash configuration files (@pxref{Bash Startup Files,,, bash, The GNU
  30083. Bash Reference Manual}.
  30084. @deftp {Data Type} home-bash-extension
  30085. Available @code{home-bash-extension} fields are:
  30086. @table @asis
  30087. @item @code{environment-variables} (default: @code{()}) (type: alist)
  30088. Additional environment variables to set. These will be combined with the
  30089. environment variables from other extensions and the base service to form one
  30090. coherent block of environment variables.
  30091. @item @code{aliases} (default: @code{()}) (type: alist)
  30092. Additional aliases to set. These will be combined with the aliases from
  30093. other extensions and the base service.
  30094. @item @code{bash-profile} (default: @code{()}) (type: text-config)
  30095. Additional text blocks to add to @file{.bash_profile}, which will be combined
  30096. with text blocks from other extensions and the base service.
  30097. @item @code{bashrc} (default: @code{()}) (type: text-config)
  30098. Additional text blocks to add to @file{.bashrc}, which will be combined
  30099. with text blocks from other extensions and the base service.
  30100. @item @code{bash-logout} (default: @code{()}) (type: text-config)
  30101. Additional text blocks to add to @file{.bash_logout}, which will be combined
  30102. with text blocks from other extensions and the base service.
  30103. @end table
  30104. @end deftp
  30105. @subsubheading Zsh Home Service
  30106. @deftp {Data Type} home-zsh-configuration
  30107. Available @code{home-zsh-configuration} fields are:
  30108. @table @asis
  30109. @item @code{package} (default: @code{zsh}) (type: package)
  30110. The Zsh package to use.
  30111. @item @code{xdg-flavor?} (default: @code{#t}) (type: boolean)
  30112. Place all the configs to @file{$XDG_CONFIG_HOME/zsh}. Makes
  30113. @file{~/.zshenv} to set @env{ZDOTDIR} to @file{$XDG_CONFIG_HOME/zsh}.
  30114. Shell startup process will continue with
  30115. @file{$XDG_CONFIG_HOME/zsh/.zshenv}.
  30116. @item @code{environment-variables} (default: @code{()}) (type: alist)
  30117. Association list of environment variables to set for the Zsh session.
  30118. @item @code{zshenv} (default: @code{()}) (type: text-config)
  30119. List of file-like objects, which will be added to @file{.zshenv}. Used
  30120. for setting user's shell environment variables. Must not contain
  30121. commands assuming the presence of tty or producing output. Will be read
  30122. always. Will be read before any other file in @env{ZDOTDIR}.
  30123. @item @code{zprofile} (default: @code{()}) (type: text-config)
  30124. List of file-like objects, which will be added to @file{.zprofile}. Used
  30125. for executing user's commands at start of login shell (In most cases the
  30126. shell started on tty just after login). Will be read before
  30127. @file{.zlogin}.
  30128. @item @code{zshrc} (default: @code{()}) (type: text-config)
  30129. List of file-like objects, which will be added to @file{.zshrc}. Used
  30130. for executing user's commands at start of interactive shell (The shell
  30131. for interactive usage started by typing @code{zsh} or by terminal app or
  30132. any other program).
  30133. @item @code{zlogin} (default: @code{()}) (type: text-config)
  30134. List of file-like objects, which will be added to @file{.zlogin}. Used
  30135. for executing user's commands at the end of starting process of login
  30136. shell.
  30137. @item @code{zlogout} (default: @code{()}) (type: text-config)
  30138. List of file-like objects, which will be added to @file{.zlogout}. Used
  30139. for executing user's commands at the exit of login shell. It won't be
  30140. read in some cases (if the shell terminates by exec'ing another process
  30141. for example).
  30142. @end table
  30143. @end deftp
  30144. @node Mcron Home Service
  30145. @subsection Scheduled User's Job Execution
  30146. @cindex cron
  30147. @cindex mcron
  30148. @cindex scheduling jobs
  30149. The @code{(gnu home services mcron)} module provides an interface to
  30150. GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
  30151. mcron, GNU@tie{}mcron}). The information about system's mcron is
  30152. applicable here (@pxref{Scheduled Job Execution}), the only difference
  30153. for home services is that they have to be declared in a
  30154. @code{home-envirnoment} record instead of an @code{operating-system}
  30155. record.
  30156. @defvr {Scheme Variable} home-mcron-service-type
  30157. This is the type of the @code{mcron} home service, whose value is an
  30158. @code{home-mcron-configuration} object. It allows to manage scheduled
  30159. tasks.
  30160. This service type can be the target of a service extension that provides
  30161. additional job specifications (@pxref{Service Composition}). In other
  30162. words, it is possible to define services that provide additional mcron
  30163. jobs to run.
  30164. @end defvr
  30165. @deftp {Data Type} home-mcron-configuration
  30166. Data type representing the configuration of mcron.
  30167. @table @asis
  30168. @item @code{mcron} (default: @var{mcron})
  30169. The mcron package to use.
  30170. @item @code{jobs}
  30171. This is a list of gexps (@pxref{G-Expressions}), where each gexp
  30172. corresponds to an mcron job specification (@pxref{Syntax, mcron job
  30173. specifications,, mcron, GNU@tie{}mcron}).
  30174. @end table
  30175. @end deftp
  30176. @node Shepherd Home Service
  30177. @subsection Managing User Daemons
  30178. @cindex shepherd services, for users
  30179. The @code{(gnu home services shepherd)} module supports the definitions
  30180. of per-user Shepherd services (@pxref{Introduction,,, shepherd, The GNU
  30181. Shepherd Manual}). You extend @code{home-shepherd-service-type} with
  30182. new services; Guix Home then takes care of starting the @code{shepherd}
  30183. daemon for you when you log in, which in turns starts the services you
  30184. asked for.
  30185. @defvr {Scheme Variable} home-shepherd-service-type
  30186. The service type for the userland Shepherd, which allows one to manage
  30187. long-running processes or one-shot tasks. User's Shepherd is not an
  30188. init process (PID 1), but almost all other information described in
  30189. (@pxref{Shepherd Services}) is applicable here too.
  30190. This is the service type that extensions target when they want to create
  30191. shepherd services (@pxref{Service Types and Services}, for an example).
  30192. Each extension must pass a list of @code{<shepherd-service>}. Its
  30193. value must be a @code{home-shepherd-configuration}, as described below.
  30194. @end defvr
  30195. @deftp {Data Type} home-shepherd-configuration
  30196. This data type represents the Shepherd's configuration.
  30197. @table @code
  30198. @item shepherd (default: @code{shepherd})
  30199. The Shepherd package to use.
  30200. @item auto-start? (default: @code{#t})
  30201. Whether or not to start Shepherd on first login.
  30202. @item services (default: @code{'()})
  30203. A list of @code{<shepherd-service>} to start.
  30204. You should probably use the service extension
  30205. mechanism instead (@pxref{Shepherd Services}).
  30206. @end table
  30207. @end deftp
  30208. @node Desktop Home Services
  30209. @subsection Desktop Home Services
  30210. The @code{(gnu home services desktop)} module provides services that you
  30211. may find useful on ``desktop'' systems running a graphical user
  30212. environment such as Xorg.
  30213. @defvr {Scheme Variable} home-redshift-service-type
  30214. This is the service type for @uref{https://github.com/jonls/redshift,
  30215. Redshift}, a program that adjusts the display color temperature
  30216. according to the time of day. Its associated value must be a
  30217. @code{home-redshift-configuration} record, as shown below.
  30218. A typical configuration, where we manually specify the latitude and
  30219. longitude, might look like this:
  30220. @lisp
  30221. (service home-redshift-service-type
  30222. (home-redshift-configuration
  30223. (location-provider 'manual)
  30224. (latitude 35.81) ;northern hemisphere
  30225. (longitude -0.80))) ;west of Greenwich
  30226. @end lisp
  30227. @end defvr
  30228. @deftp {Data Type} home-redshift-configuration
  30229. Available @code{home-redshift-configuration} fields are:
  30230. @table @asis
  30231. @item @code{redshift} (default: @code{redshift}) (type: file-like)
  30232. Redshift package to use.
  30233. @item @code{location-provider} (default: @code{geoclue2}) (type: symbol)
  30234. Geolocation provider---@code{'manual} or @code{'geoclue2}. In the
  30235. former case, you must also specify the @code{latitude} and
  30236. @code{longitude} fields so Redshift can determine daytime at your place.
  30237. In the latter case, the Geoclue system service must be running; it will
  30238. be queried for location information.
  30239. @item @code{adjustment-method} (default: @code{randr}) (type: symbol)
  30240. Color adjustment method.
  30241. @item @code{daytime-temperature} (default: @code{6500}) (type: integer)
  30242. Daytime color temperature (kelvins).
  30243. @item @code{nighttime-temperature} (default: @code{4500}) (type: integer)
  30244. Nighttime color temperature (kelvins).
  30245. @item @code{daytime-brightness} (default: @code{disabled}) (type: maybe-inexact-number)
  30246. Daytime screen brightness, between 0.1 and 1.0.
  30247. @item @code{nighttime-brightness} (default: @code{disabled}) (type: maybe-inexact-number)
  30248. Nighttime screen brightness, between 0.1 and 1.0.
  30249. @item @code{latitude} (default: @code{disabled}) (type: maybe-inexact-number)
  30250. Latitude, when @code{location-provider} is @code{'manual}.
  30251. @item @code{longitude} (default: @code{disabled}) (type: maybe-inexact-number)
  30252. Longitude, when @code{location-provider} is @code{'manual}.
  30253. @item @code{dawn-time} (default: @code{disabled}) (type: maybe-string)
  30254. Custom time for the transition from night to day in the
  30255. morning---@code{"HH:MM"} format. When specified, solar elevation is not
  30256. used to determine the daytime/nighttime period.
  30257. @item @code{dusk-time} (default: @code{disabled}) (type: maybe-string)
  30258. Likewise, custom time for the transition from day to night in the
  30259. evening.
  30260. @item @code{extra-content} (default: @code{""}) (type: raw-configuration-string)
  30261. Extra content appended as-is to the Redshift configuration file. Run
  30262. @command{man redshift} for more information about the configuration file
  30263. format.
  30264. @end table
  30265. @end deftp
  30266. @node Invoking guix home
  30267. @section Invoking @code{guix home}
  30268. Once you have written a home environment declaration (@pxref{Declaring
  30269. the Home Environment,,,,}, it can be @dfn{instantiated} using the
  30270. @command{guix home} command. The synopsis is:
  30271. @example
  30272. guix home @var{options}@dots{} @var{action} @var{file}
  30273. @end example
  30274. @var{file} must be the name of a file containing a
  30275. @code{home-environment} declaration. @var{action} specifies how the
  30276. home environment is instantiated, but there are few auxiliary actions
  30277. which don't instantiate it. Currently the following values are
  30278. supported:
  30279. @table @code
  30280. @item search
  30281. Display available home service type definitions that match the given
  30282. regular expressions, sorted by relevance:
  30283. @cindex shell
  30284. @cindex shell-profile
  30285. @cindex bash
  30286. @cindex zsh
  30287. @example
  30288. $ guix home search shell
  30289. name: home-shell-profile
  30290. location: gnu/home/services/shells.scm:100:2
  30291. extends: home-files
  30292. description: Create `~/.profile', which is used for environment initialization of POSIX compliant login shells.
  30293. + This service type can be extended with a list of file-like objects.
  30294. relevance: 6
  30295. name: home-fish
  30296. location: gnu/home/services/shells.scm:640:2
  30297. extends: home-files home-profile
  30298. description: Install and configure Fish, the friendly interactive shell.
  30299. relevance: 3
  30300. name: home-zsh
  30301. location: gnu/home/services/shells.scm:290:2
  30302. extends: home-files home-profile
  30303. description: Install and configure Zsh.
  30304. relevance: 1
  30305. name: home-bash
  30306. location: gnu/home/services/shells.scm:508:2
  30307. extends: home-files home-profile
  30308. description: Install and configure GNU Bash.
  30309. relevance: 1
  30310. @dots{}
  30311. @end example
  30312. As for @command{guix search}, the result is written in
  30313. @code{recutils} format, which makes it easy to filter the output
  30314. (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
  30315. @cindex container, for @command{guix home}
  30316. @item container
  30317. Spawn a shell in an isolated environment---a
  30318. @dfn{container}---containing your home as specified by @var{file}.
  30319. For example, this is how you would start an interactive shell in a
  30320. container with your home:
  30321. @example
  30322. guix home container config.scm
  30323. @end example
  30324. This is a throw-away container where you can lightheartedly fiddle with
  30325. files; any changes made within the container, any process started---all
  30326. this disappears as soon as you exit that shell.
  30327. As with @command{guix shell}, several options control that container:
  30328. @table @option
  30329. @item --network
  30330. @itemx -N
  30331. Enable networking within the container (it is disabled by default).
  30332. @item --expose=@var{source}[=@var{target}]
  30333. @itemx --share=@var{source}[=@var{target}]
  30334. As with @command{guix shell}, make directory @var{source} of the host
  30335. system available as @var{target} inside the container---read-only if you
  30336. pass @option{--expose}, and writable if you pass @option{--share}
  30337. (@pxref{Invoking guix shell, @option{--expose} and @option{--share}}).
  30338. @end table
  30339. Additionally, you can run a command in that container, instead of
  30340. spawning an interactive shell. For instance, here is how you would
  30341. check which Shepherd services are started in a throw-away home
  30342. container:
  30343. @example
  30344. guix home container config.scm -- herd status
  30345. @end example
  30346. The command to run in the container must come after @code{--} (double
  30347. hyphen).
  30348. @item reconfigure
  30349. Build the home environment described in @var{file}, and switch to it.
  30350. Switching means that the activation script will be evaluated and (in
  30351. basic scenario) symlinks to configuration files generated from
  30352. @code{home-environment} declaration will be created in @file{~}. If the
  30353. file with the same path already exists in home folder it will be moved
  30354. to @file{~/@var{timestamp}-guix-home-legacy-configs-backup}, where @var{timestamp}
  30355. is a current UNIX epoch time.
  30356. @quotation Note
  30357. It is highly recommended to run @command{guix pull} once before you run
  30358. @command{guix home reconfigure} for the first time (@pxref{Invoking guix
  30359. pull}).
  30360. @end quotation
  30361. This effects all the configuration specified in @var{file}. The command
  30362. starts Shepherd services specified in @var{file} that are not currently
  30363. running; if a service is currently running, this command will arrange
  30364. for it to be upgraded the next time it is stopped (e.g.@: by @code{herd
  30365. stop @var{service}} or @code{herd restart @var{service}}).
  30366. This command creates a new generation whose number is one greater than
  30367. the current generation (as reported by @command{guix home
  30368. list-generations}). If that generation already exists, it will be
  30369. overwritten. This behavior mirrors that of @command{guix package}
  30370. (@pxref{Invoking guix package}).
  30371. @cindex provenance tracking, of the home environment
  30372. Upon completion, the new home is deployed under @file{~/.guix-home}.
  30373. This directory contains @dfn{provenance meta-data}: the list of channels
  30374. in use (@pxref{Channels}) and @var{file} itself, when available. You
  30375. can view the provenance information by running:
  30376. @example
  30377. guix home describe
  30378. @end example
  30379. This information is useful should you later want to inspect how this
  30380. particular generation was built. In fact, assuming @var{file} is
  30381. self-contained, you can later rebuild generation @var{n} of your
  30382. home environment with:
  30383. @example
  30384. guix time-machine \
  30385. -C /var/guix/profiles/per-user/@var{USER}/guix-home-@var{n}-link/channels.scm -- \
  30386. home reconfigure \
  30387. /var/guix/profiles/per-user/@var{USER}/guix-home-@var{n}-link/configuration.scm
  30388. @end example
  30389. You can think of it as some sort of built-in version control! Your
  30390. home is not just a binary artifact: @emph{it carries its own source}.
  30391. @c @xref{Service Reference, @code{provenance-service-type}}, for more
  30392. @c information on provenance tracking.
  30393. @c @footnote{This action (and the related actions
  30394. @c @code{switch-generation} and @code{roll-back}) are usable after the
  30395. @c home environment is initialized.}.
  30396. @item switch-generation
  30397. @cindex home generations
  30398. Switch to an existing home generation. This action atomically switches
  30399. the home profile to the specified home generation.
  30400. The target generation can be specified explicitly by its generation
  30401. number. For example, the following invocation would switch to home
  30402. generation 7:
  30403. @example
  30404. guix home switch-generation 7
  30405. @end example
  30406. The target generation can also be specified relative to the current
  30407. generation with the form @code{+N} or @code{-N}, where @code{+3} means
  30408. ``3 generations ahead of the current generation,'' and @code{-1} means
  30409. ``1 generation prior to the current generation.'' When specifying a
  30410. negative value such as @code{-1}, you must precede it with @code{--} to
  30411. prevent it from being parsed as an option. For example:
  30412. @example
  30413. guix home switch-generation -- -1
  30414. @end example
  30415. This action will fail if the specified generation does not exist.
  30416. @item roll-back
  30417. @cindex rolling back
  30418. Switch to the preceding home generation. This is the inverse
  30419. of @command{reconfigure}, and it is exactly the same as invoking
  30420. @command{switch-generation} with an argument of @code{-1}.
  30421. @item delete-generations
  30422. @cindex deleting home generations
  30423. @cindex saving space
  30424. Delete home generations, making them candidates for garbage collection
  30425. (@pxref{Invoking guix gc}, for information on how to run the ``garbage
  30426. collector'').
  30427. This works in the same way as @samp{guix package --delete-generations}
  30428. (@pxref{Invoking guix package, @option{--delete-generations}}). With no
  30429. arguments, all home generations but the current one are deleted:
  30430. @example
  30431. guix home delete-generations
  30432. @end example
  30433. You can also select the generations you want to delete. The example below
  30434. deletes all the home generations that are more than two months old:
  30435. @example
  30436. guix home delete-generations 2m
  30437. @end example
  30438. @item build
  30439. Build the derivation of the home environment, which includes all the
  30440. configuration files and programs needed. This action does not actually
  30441. install anything.
  30442. @item describe
  30443. Describe the current home generation: its file name, as well as
  30444. provenance information when available.
  30445. @item list-generations
  30446. List a summary of each generation of the home environment available on
  30447. disk, in a human-readable way. This is similar to the
  30448. @option{--list-generations} option of @command{guix package}
  30449. (@pxref{Invoking guix package}).
  30450. Optionally, one can specify a pattern, with the same syntax that is used
  30451. in @command{guix package --list-generations}, to restrict the list of
  30452. generations displayed. For instance, the following command displays
  30453. generations that are up to 10 days old:
  30454. @example
  30455. $ guix home list-generations 10d
  30456. @end example
  30457. @item import
  30458. Generate a @dfn{home environment} from the packages in the default
  30459. profile and configuration files found in the user's home directory. The
  30460. configuration files will be copied to the specified directory, and a
  30461. @file{home-configuration.scm} will be populated with the home
  30462. environment. Note that not every home service that exists is supported
  30463. (@pxref{Home Services}).
  30464. @example
  30465. $ guix home import ~/guix-config
  30466. guix home: '/home/alice/guix-config' populated with all the Home configuration files
  30467. @end example
  30468. @end table
  30469. And there's more! @command{guix home} also provides the following
  30470. sub-commands to visualize how the services of your home environment
  30471. relate to one another:
  30472. @table @code
  30473. @cindex service extension graph, of a home environment
  30474. @item extension-graph
  30475. Emit to standard output the @dfn{service extension graph} of the home
  30476. environment defined in @var{file} (@pxref{Service Composition}, for more
  30477. information on service extensions). By default the output is in
  30478. Dot/Graphviz format, but you can choose a different format with
  30479. @option{--graph-backend}, as with @command{guix graph} (@pxref{Invoking
  30480. guix graph, @option{--backend}}):
  30481. The command:
  30482. @example
  30483. guix home extension-graph @var{file} | xdot -
  30484. @end example
  30485. shows the extension relations among services.
  30486. @cindex Shepherd dependency graph, for a home environment
  30487. @item shepherd-graph
  30488. Emit to standard output the @dfn{dependency graph} of shepherd services
  30489. of the home environment defined in @var{file}. @xref{Shepherd
  30490. Services}, for more information and for an example graph.
  30491. Again, the default output format is Dot/Graphviz, but you can pass
  30492. @option{--graph-backend} to select a different one.
  30493. @end table
  30494. @var{options} can contain any of the common build options (@pxref{Common
  30495. Build Options}). In addition, @var{options} can contain one of the
  30496. following:
  30497. @table @option
  30498. @item --expression=@var{expr}
  30499. @itemx -e @var{expr}
  30500. Consider the home-environment @var{expr} evaluates to.
  30501. This is an alternative to specifying a file which evaluates to a home
  30502. environment.
  30503. @item --allow-downgrades
  30504. Instruct @command{guix home reconfigure} to allow system downgrades.
  30505. Just like @command{guix system}, @command{guix home reconfigure}, by
  30506. default, prevents you from downgrading your home to older or unrelated
  30507. revisions compared to the channel revisions that were used to deploy
  30508. it---those shown by @command{guix home describe}. Using
  30509. @option{--allow-downgrades} allows you to bypass that check, at the risk
  30510. of downgrading your home---be careful!
  30511. @end table
  30512. @node Documentation
  30513. @chapter Documentation
  30514. @cindex documentation, searching for
  30515. @cindex searching for documentation
  30516. @cindex Info, documentation format
  30517. @cindex man pages
  30518. @cindex manual pages
  30519. In most cases packages installed with Guix come with documentation.
  30520. There are two main documentation formats: ``Info'', a browsable
  30521. hypertext format used for GNU software, and ``manual pages'' (or ``man
  30522. pages''), the linear documentation format traditionally found on Unix.
  30523. Info manuals are accessed with the @command{info} command or with Emacs,
  30524. and man pages are accessed using @command{man}.
  30525. You can look for documentation of software installed on your system by
  30526. keyword. For example, the following command searches for information
  30527. about ``TLS'' in Info manuals:
  30528. @example
  30529. $ info -k TLS
  30530. "(emacs)Network Security" -- STARTTLS
  30531. "(emacs)Network Security" -- TLS
  30532. "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
  30533. "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
  30534. @dots{}
  30535. @end example
  30536. @noindent
  30537. The command below searches for the same keyword in man
  30538. pages@footnote{The database searched by @command{man -k} is only created
  30539. in profiles that contain the @code{man-db} package.}:
  30540. @example
  30541. $ man -k TLS
  30542. SSL (7) - OpenSSL SSL/TLS library
  30543. certtool (1) - GnuTLS certificate tool
  30544. @dots {}
  30545. @end example
  30546. These searches are purely local to your computer so you have the
  30547. guarantee that documentation you find corresponds to what you have
  30548. actually installed, you can access it off-line, and your privacy is
  30549. respected.
  30550. Once you have these results, you can view the relevant documentation by
  30551. running, say:
  30552. @example
  30553. $ info "(gnutls)Core TLS API"
  30554. @end example
  30555. @noindent
  30556. or:
  30557. @example
  30558. $ man certtool
  30559. @end example
  30560. Info manuals contain sections and indices as well as hyperlinks like
  30561. those found in Web pages. The @command{info} reader (@pxref{Top, Info
  30562. reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
  30563. (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
  30564. bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
  30565. Introduction}, for an introduction to Info navigation.
  30566. @node Installing Debugging Files
  30567. @chapter Installing Debugging Files
  30568. @cindex debugging files
  30569. Program binaries, as produced by the GCC compilers for instance, are
  30570. typically written in the ELF format, with a section containing
  30571. @dfn{debugging information}. Debugging information is what allows the
  30572. debugger, GDB, to map binary code to source code; it is required to
  30573. debug a compiled program in good conditions.
  30574. This chapter explains how to use separate debug info when packages
  30575. provide it, and how to rebuild packages with debug info when it's
  30576. missing.
  30577. @menu
  30578. * Separate Debug Info:: Installing 'debug' outputs.
  30579. * Rebuilding Debug Info:: Building missing debug info.
  30580. @end menu
  30581. @node Separate Debug Info
  30582. @section Separate Debug Info
  30583. The problem with debugging information is that is takes up a fair amount
  30584. of disk space. For example, debugging information for the GNU C Library
  30585. weighs in at more than 60 MiB@. Thus, as a user, keeping all the
  30586. debugging info of all the installed programs is usually not an option.
  30587. Yet, space savings should not come at the cost of an impediment to
  30588. debugging---especially in the GNU system, which should make it easier
  30589. for users to exert their computing freedom (@pxref{GNU Distribution}).
  30590. Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
  30591. mechanism that allows users to get the best of both worlds: debugging
  30592. information can be stripped from the binaries and stored in separate
  30593. files. GDB is then able to load debugging information from those files,
  30594. when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
  30595. with GDB}).
  30596. The GNU distribution takes advantage of this by storing debugging
  30597. information in the @code{lib/debug} sub-directory of a separate package
  30598. output unimaginatively called @code{debug} (@pxref{Packages with
  30599. Multiple Outputs}). Users can choose to install the @code{debug} output
  30600. of a package when they need it. For instance, the following command
  30601. installs the debugging information for the GNU C Library and for GNU
  30602. Guile:
  30603. @example
  30604. guix install glibc:debug guile:debug
  30605. @end example
  30606. GDB must then be told to look for debug files in the user's profile, by
  30607. setting the @code{debug-file-directory} variable (consider setting it
  30608. from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
  30609. GDB}):
  30610. @example
  30611. (gdb) set debug-file-directory ~/.guix-profile/lib/debug
  30612. @end example
  30613. From there on, GDB will pick up debugging information from the
  30614. @file{.debug} files under @file{~/.guix-profile/lib/debug}.
  30615. Below is an alternative GDB script which is useful when working with
  30616. other profiles. It takes advantage of the optional Guile integration in
  30617. GDB. This snippet is included by default on Guix System in the
  30618. @file{~/.gdbinit} file.
  30619. @example
  30620. guile
  30621. (use-modules (gdb))
  30622. (execute (string-append "set debug-file-directory "
  30623. (or (getenv "GDB_DEBUG_FILE_DIRECTORY")
  30624. "~/.guix-profile/lib/debug")))
  30625. end
  30626. @end example
  30627. In addition, you will most likely want GDB to be able to show the source
  30628. code being debugged. To do that, you will have to unpack the source
  30629. code of the package of interest (obtained with @code{guix build
  30630. --source}, @pxref{Invoking guix build}), and to point GDB to that source
  30631. directory using the @code{directory} command (@pxref{Source Path,
  30632. @code{directory},, gdb, Debugging with GDB}).
  30633. @c XXX: keep me up-to-date
  30634. The @code{debug} output mechanism in Guix is implemented by the
  30635. @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
  30636. opt-in---debugging information is available only for the packages with
  30637. definitions explicitly declaring a @code{debug} output. To check
  30638. whether a package has a @code{debug} output, use @command{guix package
  30639. --list-available} (@pxref{Invoking guix package}).
  30640. Read on for how to deal with packages lacking a @code{debug} output.
  30641. @node Rebuilding Debug Info
  30642. @section Rebuilding Debug Info
  30643. @cindex debugging info, rebuilding
  30644. As we saw above, some packages, but not all, provide debugging info in a
  30645. @code{debug} output. What can you do when debugging info is missing?
  30646. The @option{--with-debug-info} option provides a solution to that: it
  30647. allows you to rebuild the package(s) for which debugging info is
  30648. missing---and only those---and to graft those onto the application
  30649. you're debugging. Thus, while it's not as fast as installing a
  30650. @code{debug} output, it is relatively inexpensive.
  30651. Let's illustrate that. Suppose you're experiencing a bug in Inkscape
  30652. and would like to see what's going on in GLib, a library that's deep
  30653. down in its dependency graph. As it turns out, GLib does not have a
  30654. @code{debug} output and the backtrace GDB shows is all sadness:
  30655. @example
  30656. (gdb) bt
  30657. #0 0x00007ffff5f92190 in g_getenv ()
  30658. from /gnu/store/@dots{}-glib-2.62.6/lib/libglib-2.0.so.0
  30659. #1 0x00007ffff608a7d6 in gobject_init_ctor ()
  30660. from /gnu/store/@dots{}-glib-2.62.6/lib/libgobject-2.0.so.0
  30661. #2 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=1, argv=argv@@entry=0x7fffffffcfd8,
  30662. env=env@@entry=0x7fffffffcfe8) at dl-init.c:72
  30663. #3 0x00007ffff7fe2866 in call_init (env=0x7fffffffcfe8, argv=0x7fffffffcfd8, argc=1, l=<optimized out>)
  30664. at dl-init.c:118
  30665. @end example
  30666. To address that, you install Inkscape linked against a variant GLib that
  30667. contains debug info:
  30668. @example
  30669. guix install inkscape --with-debug-info=glib
  30670. @end example
  30671. This time, debugging will be a whole lot nicer:
  30672. @example
  30673. $ gdb --args sh -c 'exec inkscape'
  30674. @dots{}
  30675. (gdb) b g_getenv
  30676. Function "g_getenv" not defined.
  30677. Make breakpoint pending on future shared library load? (y or [n]) y
  30678. Breakpoint 1 (g_getenv) pending.
  30679. (gdb) r
  30680. Starting program: /gnu/store/@dots{}-profile/bin/sh -c exec\ inkscape
  30681. @dots{}
  30682. (gdb) bt
  30683. #0 g_getenv (variable=variable@@entry=0x7ffff60c7a2e "GOBJECT_DEBUG") at ../glib-2.62.6/glib/genviron.c:252
  30684. #1 0x00007ffff608a7d6 in gobject_init () at ../glib-2.62.6/gobject/gtype.c:4380
  30685. #2 gobject_init_ctor () at ../glib-2.62.6/gobject/gtype.c:4493
  30686. #3 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=3, argv=argv@@entry=0x7fffffffd088,
  30687. env=env@@entry=0x7fffffffd0a8) at dl-init.c:72
  30688. @dots{}
  30689. @end example
  30690. Much better!
  30691. Note that there can be packages for which @option{--with-debug-info}
  30692. will not have the desired effect. @xref{Package Transformation Options,
  30693. @option{--with-debug-info}}, for more information.
  30694. @node Using TeX and LaTeX
  30695. @chapter Using @TeX{} and @LaTeX{}
  30696. @cindex @TeX{} packages
  30697. @cindex @LaTeX{} packages
  30698. Guix provides packages for the @TeX{}, @LaTeX{}, ConTeXt, LuaTeX, and
  30699. related typesetting systems, taken from the
  30700. @uref{https://www.tug.org/texlive/, @TeX{} Live distribution}. However,
  30701. because @TeX{} Live is so huge and because finding your way in this maze
  30702. is tricky, we thought that you, dear user, would welcome guidance on how
  30703. to deploy the relevant packages so you can compile your @TeX{} and
  30704. @LaTeX{} documents.
  30705. @TeX{} Live currently comes in two flavors in Guix:
  30706. @itemize
  30707. @item
  30708. The ``monolithic'' @code{texlive} package: it comes with @emph{every
  30709. single @TeX{} Live package} (more than 7,000 of them), but it is huge
  30710. (more than 4@tie{}GiB for a single package!).
  30711. @item
  30712. The ``modular'' @code{texlive-} packages: you install
  30713. @code{texlive-base}, which provides core functionality and the main
  30714. commands---@command{pdflatex}, @command{dvips}, @command{luatex},
  30715. @command{mf}, etc.---together with individual packages that provide just
  30716. the features you need---@code{texlive-listings} for the
  30717. @code{listings} package, @code{texlive-hyperref} for @code{hyperref},
  30718. @code{texlive-beamer} for Beamer, @code{texlive-pgf} for PGF/TikZ,
  30719. and so on.
  30720. @end itemize
  30721. We recommend using the modular package set because it is much less
  30722. resource-hungry. To build your documents, you would use commands such
  30723. as:
  30724. @example
  30725. guix shell texlive-base texlive-wrapfig \
  30726. texlive-hyperref texlive-cm-super -- pdflatex doc.tex
  30727. @end example
  30728. You can quickly end up with unreasonably long command lines though. The
  30729. solution is to instead write a manifest, for example like this one:
  30730. @lisp
  30731. (specifications->manifest
  30732. '("rubber"
  30733. "texlive-base"
  30734. "texlive-wrapfig"
  30735. "texlive-microtype"
  30736. "texlive-listings" "texlive-hyperref"
  30737. ;; PGF/TikZ
  30738. "texlive-pgf"
  30739. ;; Additional fonts.
  30740. "texlive-cm-super" "texlive-amsfonts"
  30741. "texlive-times" "texlive-helvetic" "texlive-courier"))
  30742. @end lisp
  30743. You can then pass it to any command with the @option{-m} option:
  30744. @example
  30745. guix shell -m manifest.scm -- pdflatex doc.tex
  30746. @end example
  30747. @xref{Invoking guix package, @option{--manifest}}, for more on
  30748. manifests. In the future, we plan to provide packages for @TeX{} Live
  30749. @dfn{collections}---``meta-packages'' such as @code{fontsrecommended},
  30750. @code{humanities}, or @code{langarabic} that provide the set of packages
  30751. needed in this particular domain. That will allow you to list fewer
  30752. packages.
  30753. The main difficulty here is that using the modular package set forces
  30754. you to select precisely the packages that you need. You can use
  30755. @command{guix search}, but finding the right package can prove to be
  30756. tedious. When a package is missing, @command{pdflatex} and similar
  30757. commands fail with an obscure message along the lines of:
  30758. @example
  30759. doc.tex: File `tikz.sty' not found.
  30760. doc.tex:7: Emergency stop.
  30761. @end example
  30762. @noindent
  30763. or, for a missing font:
  30764. @example
  30765. kpathsea: Running mktexmf phvr7t
  30766. ! I can't find file `phvr7t'.
  30767. @end example
  30768. How do you determine what the missing package is? In the first case,
  30769. you'll find the answer by running:
  30770. @example
  30771. $ guix search texlive tikz
  30772. name: texlive-pgf
  30773. version: 59745
  30774. @dots{}
  30775. @end example
  30776. In the second case, @command{guix search} turns up nothing. Instead,
  30777. you can search the @TeX{} Live package database using the @command{tlmgr}
  30778. command:
  30779. @example
  30780. $ guix shell texlive-base -- tlmgr info phvr7t
  30781. tlmgr: cannot find package phvr7t, searching for other matches:
  30782. Packages containing `phvr7t' in their title/description:
  30783. Packages containing files matching `phvr7t':
  30784. helvetic:
  30785. texmf-dist/fonts/tfm/adobe/helvetic/phvr7t.tfm
  30786. texmf-dist/fonts/tfm/adobe/helvetic/phvr7tn.tfm
  30787. texmf-dist/fonts/vf/adobe/helvetic/phvr7t.vf
  30788. texmf-dist/fonts/vf/adobe/helvetic/phvr7tn.vf
  30789. tex4ht:
  30790. texmf-dist/tex4ht/ht-fonts/alias/adobe/helvetic/phvr7t.htf
  30791. @end example
  30792. The file is available in the @TeX{} Live @code{helvetic} package, which is
  30793. known in Guix as @code{texlive-helvetic}. Quite a ride, but we found
  30794. it!
  30795. There is one important limitation though: Guix currently provides a
  30796. subset of the @TeX{} Live packages. If you stumble upon a missing
  30797. package, you can try and import it (@pxref{Invoking guix import}):
  30798. @example
  30799. guix import texlive @var{package}
  30800. @end example
  30801. @quotation Note
  30802. @TeX{} Live packaging is still very much work in progress, but you can
  30803. help! @xref{Contributing}, for more information.
  30804. @end quotation
  30805. @node Security Updates
  30806. @chapter Security Updates
  30807. @cindex security updates
  30808. @cindex security vulnerabilities
  30809. Occasionally, important security vulnerabilities are discovered in software
  30810. packages and must be patched. Guix developers try hard to keep track of
  30811. known vulnerabilities and to apply fixes as soon as possible in the
  30812. @code{master} branch of Guix (we do not yet provide a ``stable'' branch
  30813. containing only security updates). The @command{guix lint} tool helps
  30814. developers find out about vulnerable versions of software packages in the
  30815. distribution:
  30816. @smallexample
  30817. $ guix lint -c cve
  30818. gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
  30819. gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
  30820. gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
  30821. @dots{}
  30822. @end smallexample
  30823. @xref{Invoking guix lint}, for more information.
  30824. Guix follows a functional
  30825. package management discipline (@pxref{Introduction}), which implies
  30826. that, when a package is changed, @emph{every package that depends on it}
  30827. must be rebuilt. This can significantly slow down the deployment of
  30828. fixes in core packages such as libc or Bash, since basically the whole
  30829. distribution would need to be rebuilt. Using pre-built binaries helps
  30830. (@pxref{Substitutes}), but deployment may still take more time than
  30831. desired.
  30832. @cindex grafts
  30833. To address this, Guix implements @dfn{grafts}, a mechanism that allows
  30834. for fast deployment of critical updates without the costs associated
  30835. with a whole-distribution rebuild. The idea is to rebuild only the
  30836. package that needs to be patched, and then to ``graft'' it onto packages
  30837. explicitly installed by the user and that were previously referring to
  30838. the original package. The cost of grafting is typically very low, and
  30839. order of magnitudes lower than a full rebuild of the dependency chain.
  30840. @cindex replacements of packages, for grafts
  30841. For instance, suppose a security update needs to be applied to Bash.
  30842. Guix developers will provide a package definition for the ``fixed''
  30843. Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
  30844. Packages}). Then, the original package definition is augmented with a
  30845. @code{replacement} field pointing to the package containing the bug fix:
  30846. @lisp
  30847. (define bash
  30848. (package
  30849. (name "bash")
  30850. ;; @dots{}
  30851. (replacement bash-fixed)))
  30852. @end lisp
  30853. From there on, any package depending directly or indirectly on Bash---as
  30854. reported by @command{guix gc --requisites} (@pxref{Invoking guix
  30855. gc})---that is installed is automatically ``rewritten'' to refer to
  30856. @code{bash-fixed} instead of @code{bash}. This grafting process takes
  30857. time proportional to the size of the package, usually less than a
  30858. minute for an ``average'' package on a recent machine. Grafting is
  30859. recursive: when an indirect dependency requires grafting, then grafting
  30860. ``propagates'' up to the package that the user is installing.
  30861. Currently, the length of the name and version of the graft and that of
  30862. the package it replaces (@code{bash-fixed} and @code{bash} in the example
  30863. above) must be equal. This restriction mostly comes from the fact that
  30864. grafting works by patching files, including binary files, directly.
  30865. Other restrictions may apply: for instance, when adding a graft to a
  30866. package providing a shared library, the original shared library and its
  30867. replacement must have the same @code{SONAME} and be binary-compatible.
  30868. The @option{--no-grafts} command-line option allows you to forcefully
  30869. avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
  30870. Thus, the command:
  30871. @example
  30872. guix build bash --no-grafts
  30873. @end example
  30874. @noindent
  30875. returns the store file name of the original Bash, whereas:
  30876. @example
  30877. guix build bash
  30878. @end example
  30879. @noindent
  30880. returns the store file name of the ``fixed'', replacement Bash. This
  30881. allows you to distinguish between the two variants of Bash.
  30882. To verify which Bash your whole profile refers to, you can run
  30883. (@pxref{Invoking guix gc}):
  30884. @example
  30885. guix gc -R $(readlink -f ~/.guix-profile) | grep bash
  30886. @end example
  30887. @noindent
  30888. @dots{} and compare the store file names that you get with those above.
  30889. Likewise for a complete Guix system generation:
  30890. @example
  30891. guix gc -R $(guix system build my-config.scm) | grep bash
  30892. @end example
  30893. Lastly, to check which Bash running processes are using, you can use the
  30894. @command{lsof} command:
  30895. @example
  30896. lsof | grep /gnu/store/.*bash
  30897. @end example
  30898. @node Bootstrapping
  30899. @chapter Bootstrapping
  30900. @c Adapted from the ELS 2013 paper.
  30901. @cindex bootstrapping
  30902. Bootstrapping in our context refers to how the distribution gets built
  30903. ``from nothing''. Remember that the build environment of a derivation
  30904. contains nothing but its declared inputs (@pxref{Introduction}). So
  30905. there's an obvious chicken-and-egg problem: how does the first package
  30906. get built? How does the first compiler get compiled?
  30907. It is tempting to think of this question as one that only die-hard
  30908. hackers may care about. However, while the answer to that question is
  30909. technical in nature, its implications are wide-ranging. How the
  30910. distribution is bootstrapped defines the extent to which we, as
  30911. individuals and as a collective of users and hackers, can trust the
  30912. software we run. It is a central concern from the standpoint of
  30913. @emph{security} and from a @emph{user freedom} viewpoint.
  30914. @cindex bootstrap binaries
  30915. The GNU system is primarily made of C code, with libc at its core. The
  30916. GNU build system itself assumes the availability of a Bourne shell and
  30917. command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
  30918. `grep'. Furthermore, build programs---programs that run
  30919. @code{./configure}, @code{make}, etc.---are written in Guile Scheme
  30920. (@pxref{Derivations}). Consequently, to be able to build anything at
  30921. all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
  30922. Binutils, libc, and the other packages mentioned above---the
  30923. @dfn{bootstrap binaries}.
  30924. These bootstrap binaries are ``taken for granted'', though we can also
  30925. re-create them if needed (@pxref{Preparing to Use the Bootstrap
  30926. Binaries}).
  30927. @menu
  30928. * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
  30929. * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
  30930. @end menu
  30931. @node Reduced Binary Seed Bootstrap
  30932. @section The Reduced Binary Seed Bootstrap
  30933. Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
  30934. a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
  30935. Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
  30936. GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
  30937. ``taken for granted.''
  30938. Taking the bootstrap binaries for granted means that we consider them to
  30939. be a correct and trustworthy ``seed'' for building the complete system.
  30940. Therein lies a problem: the combined size of these bootstrap binaries is
  30941. about 250MB (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing
  30942. or even inspecting these is next to impossible.
  30943. For @code{i686-linux} and @code{x86_64-linux}, Guix now features a
  30944. ``Reduced Binary Seed'' bootstrap @footnote{We would like to say: ``Full
  30945. Source Bootstrap'' and while we are working towards that goal it would
  30946. be hyperbole to use that term for what we do now.}.
  30947. The Reduced Binary Seed bootstrap removes the most critical tools---from a
  30948. trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
  30949. Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
  30950. linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
  30951. written in Scheme and the Mes C Library, built for TinyCC and for GCC).
  30952. Using these new binary seeds the ``missing'' Binutils, GCC, and the GNU
  30953. C Library are built from source. From here on the more traditional
  30954. bootstrap process resumes. This approach has reduced the bootstrap
  30955. binaries in size to about 145MB in Guix v1.1.
  30956. The next step that Guix has taken is to replace the shell and all its
  30957. utilities with implementations in Guile Scheme, the @emph{Scheme-only
  30958. bootstrap}. Gash (@pxref{Gash,,, gash, The Gash manual}) is a
  30959. POSIX-compatible shell that replaces Bash, and it comes with Gash Utils
  30960. which has minimalist replacements for Awk, the GNU Core Utilities, Grep,
  30961. Gzip, Sed, and Tar. The rest of the bootstrap binary seeds that were
  30962. removed are now built from source.
  30963. Building the GNU System from source is currently only possible by adding
  30964. some historical GNU packages as intermediate steps@footnote{Packages
  30965. such as @code{gcc-2.95.3}, @code{binutils-2.14}, @code{glibc-2.2.5},
  30966. @code{gzip-1.2.4}, @code{tar-1.22}, and some others. For details, see
  30967. @file{gnu/packages/commencement.scm}.}. As Gash and Gash Utils mature,
  30968. and GNU packages become more bootstrappable again (e.g., new releases of
  30969. GNU Sed will also ship as gzipped tarballs again, as alternative to the
  30970. hard to bootstrap @code{xz}-compression), this set of added packages can
  30971. hopefully be reduced again.
  30972. The graph below shows the resulting dependency graph for
  30973. @code{gcc-core-mesboot0}, the bootstrap compiler used for the
  30974. traditional bootstrap of the rest of the Guix System.
  30975. @c ./pre-inst-env guix graph -e '(@@ (gnu packages commencement) gcc-core-mesboot0)' | sed -re 's,((bootstrap-mescc-tools|bootstrap-mes|guile-bootstrap).*shape =) box,\1 ellipse,' > doc/images/gcc-core-mesboot0-graph.dot
  30976. @image{images/gcc-core-mesboot0-graph,6in,,Dependency graph of gcc-core-mesboot0}
  30977. The only significant binary bootstrap seeds that remain@footnote{
  30978. Ignoring the 68KB @code{mescc-tools}; that will be removed later,
  30979. together with @code{mes}.} are a Scheme interpreter and a Scheme
  30980. compiler: GNU Mes and GNU Guile@footnote{Not shown in this graph are the
  30981. static binaries for @file{bash}, @code{tar}, and @code{xz} that are used
  30982. to get Guile running.}.
  30983. This further reduction has brought down the size of the binary seed to
  30984. about 60MB for @code{i686-linux} and @code{x86_64-linux}.
  30985. Work is ongoing to remove all binary blobs from our free software
  30986. bootstrap stack, working towards a Full Source Bootstrap. Also ongoing
  30987. is work to bring these bootstraps to the @code{arm-linux} and
  30988. @code{aarch64-linux} architectures and to the Hurd.
  30989. If you are interested, join us on @samp{#bootstrappable} on the Freenode
  30990. IRC network or discuss on @email{bug-mes@@gnu.org} or
  30991. @email{gash-devel@@nongnu.org}.
  30992. @node Preparing to Use the Bootstrap Binaries
  30993. @section Preparing to Use the Bootstrap Binaries
  30994. @c As of Emacs 24.3, Info-mode displays the image, but since it's a
  30995. @c large image, it's hard to scroll. Oh well.
  30996. @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
  30997. The figure above shows the very beginning of the dependency graph of the
  30998. distribution, corresponding to the package definitions of the @code{(gnu
  30999. packages bootstrap)} module. A similar figure can be generated with
  31000. @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
  31001. @example
  31002. guix graph -t derivation \
  31003. -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
  31004. | dot -Tps > gcc.ps
  31005. @end example
  31006. or, for the further Reduced Binary Seed bootstrap
  31007. @example
  31008. guix graph -t derivation \
  31009. -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
  31010. | dot -Tps > mes.ps
  31011. @end example
  31012. At this level of detail, things are
  31013. slightly complex. First, Guile itself consists of an ELF executable,
  31014. along with many source and compiled Scheme files that are dynamically
  31015. loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
  31016. tarball shown in this graph. This tarball is part of Guix's ``source''
  31017. distribution, and gets inserted into the store with @code{add-to-store}
  31018. (@pxref{The Store}).
  31019. But how do we write a derivation that unpacks this tarball and adds it
  31020. to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
  31021. derivation---the first one that gets built---uses @code{bash} as its
  31022. builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
  31023. @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
  31024. @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
  31025. the Guix source distribution, whose sole purpose is to allow the Guile
  31026. tarball to be unpacked.
  31027. Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
  31028. Guile that can be used to run subsequent build programs. Its first task
  31029. is to download tarballs containing the other pre-built binaries---this
  31030. is what the @file{.tar.xz.drv} derivations do. Guix modules such as
  31031. @code{ftp-client.scm} are used for this purpose. The
  31032. @code{module-import.drv} derivations import those modules in a directory
  31033. in the store, using the original layout. The
  31034. @code{module-import-compiled.drv} derivations compile those modules, and
  31035. write them in an output directory with the right layout. This
  31036. corresponds to the @code{#:modules} argument of
  31037. @code{build-expression->derivation} (@pxref{Derivations}).
  31038. Finally, the various tarballs are unpacked by the derivations
  31039. @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
  31040. @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
  31041. point we have a working C tool chain.
  31042. @unnumberedsec Building the Build Tools
  31043. Bootstrapping is complete when we have a full tool chain that does not
  31044. depend on the pre-built bootstrap tools discussed above. This
  31045. no-dependency requirement is verified by checking whether the files of
  31046. the final tool chain contain references to the @file{/gnu/store}
  31047. directories of the bootstrap inputs. The process that leads to this
  31048. ``final'' tool chain is described by the package definitions found in
  31049. the @code{(gnu packages commencement)} module.
  31050. The @command{guix graph} command allows us to ``zoom out'' compared to
  31051. the graph above, by looking at the level of package objects instead of
  31052. individual derivations---remember that a package may translate to
  31053. several derivations, typically one derivation to download its source,
  31054. one to build the Guile modules it needs, and one to actually build the
  31055. package from source. The command:
  31056. @example
  31057. guix graph -t bag \
  31058. -e '(@@@@ (gnu packages commencement)
  31059. glibc-final-with-bootstrap-bash)' | xdot -
  31060. @end example
  31061. @noindent
  31062. displays the dependency graph leading to the ``final'' C
  31063. library@footnote{You may notice the @code{glibc-intermediate} label,
  31064. suggesting that it is not @emph{quite} final, but as a good
  31065. approximation, we will consider it final.}, depicted below.
  31066. @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
  31067. @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
  31068. The first tool that gets built with the bootstrap binaries is
  31069. GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
  31070. for all the following packages. From there Findutils and Diffutils get
  31071. built.
  31072. Then come the first-stage Binutils and GCC, built as pseudo cross
  31073. tools---i.e., with @option{--target} equal to @option{--host}. They are
  31074. used to build libc. Thanks to this cross-build trick, this libc is
  31075. guaranteed not to hold any reference to the initial tool chain.
  31076. From there the final Binutils and GCC (not shown above) are built. GCC
  31077. uses @command{ld} from the final Binutils, and links programs against
  31078. the just-built libc. This tool chain is used to build the other
  31079. packages used by Guix and by the GNU Build System: Guile, Bash,
  31080. Coreutils, etc.
  31081. And voilà! At this point we have the complete set of build tools that
  31082. the GNU Build System expects. These are in the @code{%final-inputs}
  31083. variable of the @code{(gnu packages commencement)} module, and are
  31084. implicitly used by any package that uses @code{gnu-build-system}
  31085. (@pxref{Build Systems, @code{gnu-build-system}}).
  31086. @unnumberedsec Building the Bootstrap Binaries
  31087. @cindex bootstrap binaries
  31088. Because the final tool chain does not depend on the bootstrap binaries,
  31089. those rarely need to be updated. Nevertheless, it is useful to have an
  31090. automated way to produce them, should an update occur, and this is what
  31091. the @code{(gnu packages make-bootstrap)} module provides.
  31092. The following command builds the tarballs containing the bootstrap binaries
  31093. (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
  31094. bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
  31095. and Guile, and a tarball containing a mixture of Coreutils and other basic
  31096. command-line tools):
  31097. @example
  31098. guix build bootstrap-tarballs
  31099. @end example
  31100. The generated tarballs are those that should be referred to in the
  31101. @code{(gnu packages bootstrap)} module mentioned at the beginning of
  31102. this section.
  31103. Still here? Then perhaps by now you've started to wonder: when do we
  31104. reach a fixed point? That is an interesting question! The answer is
  31105. unknown, but if you would like to investigate further (and have
  31106. significant computational and storage resources to do so), then let us
  31107. know.
  31108. @unnumberedsec Reducing the Set of Bootstrap Binaries
  31109. Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
  31110. binary code! Why is that a problem? It's a problem because these big chunks
  31111. of binary code are practically non-auditable, which makes it hard to establish
  31112. what source code produced them. Every unauditable binary also leaves us
  31113. vulnerable to compiler backdoors as described by Ken Thompson in the 1984
  31114. paper @emph{Reflections on Trusting Trust}.
  31115. This is mitigated by the fact that our bootstrap binaries were generated
  31116. from an earlier Guix revision. Nevertheless it lacks the level of
  31117. transparency that we get in the rest of the package dependency graph,
  31118. where Guix always gives us a source-to-binary mapping. Thus, our goal
  31119. is to reduce the set of bootstrap binaries to the bare minimum.
  31120. The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
  31121. on-going projects to do that. One of these is about replacing the
  31122. bootstrap GCC with a sequence of assemblers, interpreters, and compilers
  31123. of increasing complexity, which could be built from source starting from
  31124. a simple and auditable assembler.
  31125. Our first major achievement is the replacement of of GCC, the GNU C Library
  31126. and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
  31127. (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
  31128. and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
  31129. bootstrapped yet and thus we inject them as binary seeds. We call this the
  31130. Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
  31131. binaries! Also, it has eliminated the C compiler binary; i686-linux and
  31132. x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
  31133. Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
  31134. also looking at any other bootstrap binaries. Your help is welcome!
  31135. @node Porting
  31136. @chapter Porting to a New Platform
  31137. As discussed above, the GNU distribution is self-contained, and
  31138. self-containment is achieved by relying on pre-built ``bootstrap
  31139. binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
  31140. operating system kernel, CPU architecture, and application binary
  31141. interface (ABI). Thus, to port the distribution to a platform that is
  31142. not yet supported, one must build those bootstrap binaries, and update
  31143. the @code{(gnu packages bootstrap)} module to use them on that platform.
  31144. Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
  31145. When everything goes well, and assuming the GNU tool chain supports the
  31146. target platform, this can be as simple as running a command like this
  31147. one:
  31148. @example
  31149. guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
  31150. @end example
  31151. For this to work, the @code{glibc-dynamic-linker} procedure in
  31152. @code{(gnu packages bootstrap)} must be augmented to return the right
  31153. file name for libc's dynamic linker on that platform; likewise,
  31154. @code{system->linux-architecture} in @code{(gnu packages linux)} must be
  31155. taught about the new platform.
  31156. Once these are built, the @code{(gnu packages bootstrap)} module needs
  31157. to be updated to refer to these binaries on the target platform. That
  31158. is, the hashes and URLs of the bootstrap tarballs for the new platform
  31159. must be added alongside those of the currently supported platforms. The
  31160. bootstrap Guile tarball is treated specially: it is expected to be
  31161. available locally, and @file{gnu/local.mk} has rules to download it for
  31162. the supported architectures; a rule for the new platform must be added
  31163. as well.
  31164. In practice, there may be some complications. First, it may be that the
  31165. extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
  31166. above) is not recognized by all the GNU tools. Typically, glibc
  31167. recognizes some of these, whereas GCC uses an extra @option{--with-abi}
  31168. configure flag (see @code{gcc.scm} for examples of how to handle this).
  31169. Second, some of the required packages could fail to build for that
  31170. platform. Lastly, the generated binaries could be broken for some
  31171. reason.
  31172. @c *********************************************************************
  31173. @include contributing.texi
  31174. @c *********************************************************************
  31175. @node Acknowledgments
  31176. @chapter Acknowledgments
  31177. Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
  31178. which was designed and
  31179. implemented by Eelco Dolstra, with contributions from other people (see
  31180. the @file{nix/AUTHORS} file in Guix). Nix pioneered functional package
  31181. management, and promoted unprecedented features, such as transactional
  31182. package upgrades and rollbacks, per-user profiles, and referentially
  31183. transparent build processes. Without this work, Guix would not exist.
  31184. The Nix-based software distributions, Nixpkgs and NixOS, have also been
  31185. an inspiration for Guix.
  31186. GNU@tie{}Guix itself is a collective work with contributions from a
  31187. number of people. See the @file{AUTHORS} file in Guix for more
  31188. information on these fine people. The @file{THANKS} file lists people
  31189. who have helped by reporting bugs, taking care of the infrastructure,
  31190. providing artwork and themes, making suggestions, and more---thank you!
  31191. @c *********************************************************************
  31192. @node GNU Free Documentation License
  31193. @appendix GNU Free Documentation License
  31194. @cindex license, GNU Free Documentation License
  31195. @include fdl-1.3.texi
  31196. @c *********************************************************************
  31197. @node Concept Index
  31198. @unnumbered Concept Index
  31199. @printindex cp
  31200. @node Programming Index
  31201. @unnumbered Programming Index
  31202. @syncodeindex tp fn
  31203. @syncodeindex vr fn
  31204. @printindex fn
  31205. @bye
  31206. @c Local Variables:
  31207. @c ispell-local-dictionary: "american";
  31208. @c End: