guix.texi 1.2 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 3CE464558A84FDC69DB40CFB090B11993D9AEBB5
  11. @set OPENPGP-SIGNING-KEY-URL https://sv.gnu.org/people/viewgpg.php?user_id=15145
  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 ci.guix.gnu.org
  16. @set SUBSTITUTE-URL https://@value{SUBSTITUTE-SERVER}
  17. @copying
  18. Copyright @copyright{} 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021 Ludovic Courtès@*
  19. Copyright @copyright{} 2013, 2014, 2016 Andreas Enge@*
  20. Copyright @copyright{} 2013 Nikita Karetnikov@*
  21. Copyright @copyright{} 2014, 2015, 2016 Alex Kost@*
  22. Copyright @copyright{} 2015, 2016 Mathieu Lirzin@*
  23. Copyright @copyright{} 2014 Pierre-Antoine Rault@*
  24. Copyright @copyright{} 2015 Taylan Ulrich Bayırlı/Kammer@*
  25. Copyright @copyright{} 2015, 2016, 2017, 2019, 2020, 2021 Leo Famulari@*
  26. Copyright @copyright{} 2015, 2016, 2017, 2018, 2019, 2020 Ricardo Wurmus@*
  27. Copyright @copyright{} 2016 Ben Woodcroft@*
  28. Copyright @copyright{} 2016, 2017, 2018 Chris Marusich@*
  29. Copyright @copyright{} 2016, 2017, 2018, 2019, 2020, 2021 Efraim Flashner@*
  30. Copyright @copyright{} 2016 John Darrington@*
  31. Copyright @copyright{} 2016, 2017 Nikita Gillmann@*
  32. Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Jan Nieuwenhuizen@*
  33. Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Julien Lepiller@*
  34. Copyright @copyright{} 2016 Alex ter Weele@*
  35. Copyright @copyright{} 2016, 2017, 2018, 2019 Christopher Baines@*
  36. Copyright @copyright{} 2017, 2018, 2019 Clément Lassieur@*
  37. Copyright @copyright{} 2017, 2018, 2020, 2021 Mathieu Othacehe@*
  38. Copyright @copyright{} 2017 Federico Beffa@*
  39. Copyright @copyright{} 2017, 2018 Carlo Zancanaro@*
  40. Copyright @copyright{} 2017 Thomas Danckaert@*
  41. Copyright @copyright{} 2017 humanitiesNerd@*
  42. Copyright @copyright{} 2017, 2021 Christopher Lemmer Webber@*
  43. Copyright @copyright{} 2017, 2018, 2019, 2020 Marius Bakke@*
  44. Copyright @copyright{} 2017, 2019, 2020 Hartmut Goebel@*
  45. Copyright @copyright{} 2017, 2019, 2020, 2021 Maxim Cournoyer@*
  46. Copyright @copyright{} 2017, 2018, 2019, 2020 Tobias Geerinckx-Rice@*
  47. Copyright @copyright{} 2017 George Clemmer@*
  48. Copyright @copyright{} 2017 Andy Wingo@*
  49. Copyright @copyright{} 2017, 2018, 2019, 2020 Arun Isaac@*
  50. Copyright @copyright{} 2017 nee@*
  51. Copyright @copyright{} 2018 Rutger Helling@*
  52. Copyright @copyright{} 2018, 2021 Oleg Pykhalov@*
  53. Copyright @copyright{} 2018 Mike Gerwitz@*
  54. Copyright @copyright{} 2018 Pierre-Antoine Rouby@*
  55. Copyright @copyright{} 2018, 2019 Gábor Boskovits@*
  56. Copyright @copyright{} 2018, 2019, 2020 Florian Pelz@*
  57. Copyright @copyright{} 2018 Laura Lazzati@*
  58. Copyright @copyright{} 2018 Alex Vong@*
  59. Copyright @copyright{} 2019 Josh Holland@*
  60. Copyright @copyright{} 2019, 2020 Diego Nicola Barbato@*
  61. Copyright @copyright{} 2019 Ivan Petkov@*
  62. Copyright @copyright{} 2019 Jakob L. Kreuze@*
  63. Copyright @copyright{} 2019 Kyle Andrews@*
  64. Copyright @copyright{} 2019 Alex Griffin@*
  65. Copyright @copyright{} 2019, 2020 Guillaume Le Vaillant@*
  66. Copyright @copyright{} 2020 Leo Prikler@*
  67. Copyright @copyright{} 2019, 2020 Simon Tournier@*
  68. Copyright @copyright{} 2020 Wiktor Żelazny@*
  69. Copyright @copyright{} 2020 Damien Cassou@*
  70. Copyright @copyright{} 2020 Jakub Kądziołka@*
  71. Copyright @copyright{} 2020 Jack Hill@*
  72. Copyright @copyright{} 2020 Naga Malleswari@*
  73. Copyright @copyright{} 2020 Brice Waegeneire@*
  74. Copyright @copyright{} 2020 R Veera Kumar@*
  75. Copyright @copyright{} 2020 Pierre Langlois@*
  76. Copyright @copyright{} 2020 pinoaffe@*
  77. Copyright @copyright{} 2020 André Batista@*
  78. Copyright @copyright{} 2020, 2021 Alexandru-Sergiu Marton@*
  79. Copyright @copyright{} 2020 raingloom@*
  80. Copyright @copyright{} 2020 Daniel Brooks@*
  81. Copyright @copyright{} 2020 John Soo@*
  82. Copyright @copyright{} 2020 Jonathan Brielmaier@*
  83. Copyright @copyright{} 2020 Edgar Vincent@*
  84. Permission is granted to copy, distribute and/or modify this document
  85. under the terms of the GNU Free Documentation License, Version 1.3 or
  86. any later version published by the Free Software Foundation; with no
  87. Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
  88. copy of the license is included in the section entitled ``GNU Free
  89. Documentation License''.
  90. @end copying
  91. @dircategory System administration
  92. @direntry
  93. * Guix: (guix). Manage installed software and system configuration.
  94. * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
  95. * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
  96. * guix pull: (guix)Invoking guix pull. Update the list of available packages.
  97. * guix system: (guix)Invoking guix system. Manage the operating system configuration.
  98. * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
  99. @end direntry
  100. @dircategory Software development
  101. @direntry
  102. * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
  103. * guix build: (guix)Invoking guix build. Building packages.
  104. * guix pack: (guix)Invoking guix pack. Creating binary bundles.
  105. @end direntry
  106. @titlepage
  107. @title GNU Guix Reference Manual
  108. @subtitle Using the GNU Guix Functional Package Manager
  109. @author The GNU Guix Developers
  110. @page
  111. @vskip 0pt plus 1filll
  112. Edition @value{EDITION} @*
  113. @value{UPDATED} @*
  114. @insertcopying
  115. @end titlepage
  116. @contents
  117. @c *********************************************************************
  118. @node Top
  119. @top GNU Guix
  120. This document describes GNU Guix version @value{VERSION}, a functional
  121. package management tool written for the GNU system.
  122. @c TRANSLATORS: You can replace the following paragraph with information on
  123. @c how to join your own translation team and how to report issues with the
  124. @c translation.
  125. This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
  126. GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
  127. Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
  128. Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
  129. Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
  130. would like to translate it in your native language, consider joining
  131. @uref{https://translate.fedoraproject.org/projects/guix/documentation-manual,
  132. Weblate}.
  133. @menu
  134. * Introduction:: What is Guix about?
  135. * Installation:: Installing Guix.
  136. * System Installation:: Installing the whole operating system.
  137. * Getting Started:: Your first steps.
  138. * Package Management:: Package installation, upgrade, etc.
  139. * Channels:: Customizing the package collection.
  140. * Development:: Guix-aided software development.
  141. * Programming Interface:: Using Guix in Scheme.
  142. * Utilities:: Package management commands.
  143. * System Configuration:: Configuring the operating system.
  144. * Documentation:: Browsing software user manuals.
  145. * Installing Debugging Files:: Feeding the debugger.
  146. * Security Updates:: Deploying security fixes quickly.
  147. * Bootstrapping:: GNU/Linux built from scratch.
  148. * Porting:: Targeting another platform or kernel.
  149. * Contributing:: Your help needed!
  150. * Acknowledgments:: Thanks!
  151. * GNU Free Documentation License:: The license of this manual.
  152. * Concept Index:: Concepts.
  153. * Programming Index:: Data types, functions, and variables.
  154. @detailmenu
  155. --- The Detailed Node Listing ---
  156. Introduction
  157. * Managing Software the Guix Way:: What's special.
  158. * GNU Distribution:: The packages and tools.
  159. Installation
  160. * Binary Installation:: Getting Guix running in no time!
  161. * Requirements:: Software needed to build and run Guix.
  162. * Running the Test Suite:: Testing Guix.
  163. * Setting Up the Daemon:: Preparing the build daemon's environment.
  164. * Invoking guix-daemon:: Running the build daemon.
  165. * Application Setup:: Application-specific setup.
  166. * Upgrading Guix:: Upgrading Guix and its build daemon.
  167. Setting Up the Daemon
  168. * Build Environment Setup:: Preparing the isolated build environment.
  169. * Daemon Offload Setup:: Offloading builds to remote machines.
  170. * SELinux Support:: Using an SELinux policy for the daemon.
  171. System Installation
  172. * Limitations:: What you can expect.
  173. * Hardware Considerations:: Supported hardware.
  174. * USB Stick and DVD Installation:: Preparing the installation medium.
  175. * Preparing for Installation:: Networking, partitioning, etc.
  176. * Guided Graphical Installation:: Easy graphical installation.
  177. * Manual Installation:: Manual installation for wizards.
  178. * After System Installation:: When installation succeeded.
  179. * Installing Guix in a VM:: Guix System playground.
  180. * Building the Installation Image:: How this comes to be.
  181. Manual Installation
  182. * Keyboard Layout and Networking and Partitioning:: Initial setup.
  183. * Proceeding with the Installation:: Installing.
  184. Package Management
  185. * Features:: How Guix will make your life brighter.
  186. * Invoking guix package:: Package installation, removal, etc.
  187. * Substitutes:: Downloading pre-built binaries.
  188. * Packages with Multiple Outputs:: Single source package, multiple outputs.
  189. * Invoking guix gc:: Running the garbage collector.
  190. * Invoking guix pull:: Fetching the latest Guix and distribution.
  191. * Invoking guix time-machine:: Running an older revision of Guix.
  192. * Inferiors:: Interacting with another revision of Guix.
  193. * Invoking guix describe:: Display information about your Guix revision.
  194. * Invoking guix archive:: Exporting and importing store files.
  195. Substitutes
  196. * Official Substitute Server:: One particular source of substitutes.
  197. * Substitute Server Authorization:: How to enable or disable substitutes.
  198. * Getting Substitutes from Other Servers:: Substitute diversity.
  199. * Substitute Authentication:: How Guix verifies substitutes.
  200. * Proxy Settings:: How to get substitutes via proxy.
  201. * Substitution Failure:: What happens when substitution fails.
  202. * On Trusting Binaries:: How can you trust that binary blob?
  203. Channels
  204. * Specifying Additional Channels:: Extending the package collection.
  205. * Using a Custom Guix Channel:: Using a customized Guix.
  206. * Replicating Guix:: Running the @emph{exact same} Guix.
  207. * Channel Authentication:: How Guix verifies what it fetches.
  208. * Creating a Channel:: How to write your custom channel.
  209. * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
  210. * Declaring Channel Dependencies:: How to depend on other channels.
  211. * Specifying Channel Authorizations:: Defining channel authors authorizations.
  212. * Primary URL:: Distinguishing mirror to original.
  213. * Writing Channel News:: Communicating information to channel's users.
  214. * Channels with Substitutes:: Using channels with available substitutes.
  215. Development
  216. * Invoking guix environment:: Setting up development environments.
  217. * Invoking guix pack:: Creating software bundles.
  218. * The GCC toolchain:: Working with languages supported by GCC.
  219. * Invoking guix git authenticate:: Authenticating Git repositories.
  220. Programming Interface
  221. * Package Modules:: Packages from the programmer's viewpoint.
  222. * Defining Packages:: Defining new packages.
  223. * Defining Package Variants:: Customizing packages.
  224. * Build Systems:: Specifying how packages are built.
  225. * Build Phases:: Phases of the build process of a package.
  226. * Build Utilities:: Helpers for your package definitions and more.
  227. * The Store:: Manipulating the package store.
  228. * Derivations:: Low-level interface to package derivations.
  229. * The Store Monad:: Purely functional interface to the store.
  230. * G-Expressions:: Manipulating build expressions.
  231. * Invoking guix repl:: Programming Guix in Guile.
  232. Defining Packages
  233. * package Reference:: The package data type.
  234. * origin Reference:: The origin data type.
  235. Utilities
  236. * Invoking guix build:: Building packages from the command line.
  237. * Invoking guix edit:: Editing package definitions.
  238. * Invoking guix download:: Downloading a file and printing its hash.
  239. * Invoking guix hash:: Computing the cryptographic hash of a file.
  240. * Invoking guix import:: Importing package definitions.
  241. * Invoking guix refresh:: Updating package definitions.
  242. * Invoking guix lint:: Finding errors in package definitions.
  243. * Invoking guix size:: Profiling disk usage.
  244. * Invoking guix graph:: Visualizing the graph of packages.
  245. * Invoking guix publish:: Sharing substitutes.
  246. * Invoking guix challenge:: Challenging substitute servers.
  247. * Invoking guix copy:: Copying to and from a remote store.
  248. * Invoking guix container:: Process isolation.
  249. * Invoking guix weather:: Assessing substitute availability.
  250. * Invoking guix processes:: Listing client processes.
  251. Invoking @command{guix build}
  252. * Common Build Options:: Build options for most commands.
  253. * Package Transformation Options:: Creating variants of packages.
  254. * Additional Build Options:: Options specific to 'guix build'.
  255. * Debugging Build Failures:: Real life packaging experience.
  256. System Configuration
  257. * Using the Configuration System:: Customizing your GNU system.
  258. * operating-system Reference:: Detail of operating-system declarations.
  259. * File Systems:: Configuring file system mounts.
  260. * Mapped Devices:: Block device extra processing.
  261. * User Accounts:: Specifying user accounts.
  262. * Keyboard Layout:: How the system interprets key strokes.
  263. * Locales:: Language and cultural convention settings.
  264. * Services:: Specifying system services.
  265. * Setuid Programs:: Programs running with root privileges.
  266. * X.509 Certificates:: Authenticating HTTPS servers.
  267. * Name Service Switch:: Configuring libc's name service switch.
  268. * Initial RAM Disk:: Linux-Libre bootstrapping.
  269. * Bootloader Configuration:: Configuring the boot loader.
  270. * Invoking guix system:: Instantiating a system configuration.
  271. * Invoking guix deploy:: Deploying a system configuration to a remote host.
  272. * Running Guix in a VM:: How to run Guix System in a virtual machine.
  273. * Defining Services:: Adding new service definitions.
  274. Services
  275. * Base Services:: Essential system services.
  276. * Scheduled Job Execution:: The mcron service.
  277. * Log Rotation:: The rottlog service.
  278. * Networking Services:: Network setup, SSH daemon, etc.
  279. * Unattended Upgrades:: Automated system upgrades.
  280. * X Window:: Graphical display.
  281. * Printing Services:: Local and remote printer support.
  282. * Desktop Services:: D-Bus and desktop services.
  283. * Sound Services:: ALSA and Pulseaudio services.
  284. * Database Services:: SQL databases, key-value stores, etc.
  285. * Mail Services:: IMAP, POP3, SMTP, and all that.
  286. * Messaging Services:: Messaging services.
  287. * Telephony Services:: Telephony services.
  288. * Monitoring Services:: Monitoring services.
  289. * Kerberos Services:: Kerberos services.
  290. * LDAP Services:: LDAP services.
  291. * Web Services:: Web servers.
  292. * Certificate Services:: TLS certificates via Let's Encrypt.
  293. * DNS Services:: DNS daemons.
  294. * VPN Services:: VPN daemons.
  295. * Network File System:: NFS related services.
  296. * Continuous Integration:: The Cuirass service.
  297. * Power Management Services:: Extending battery life.
  298. * Audio Services:: The MPD.
  299. * Virtualization Services:: Virtualization services.
  300. * Version Control Services:: Providing remote access to Git repositories.
  301. * Game Services:: Game servers.
  302. * PAM Mount Service:: Service to mount volumes when logging in.
  303. * Guix Services:: Services relating specifically to Guix.
  304. * Linux Services:: Services tied to the Linux kernel.
  305. * Hurd Services:: Services specific for a Hurd System.
  306. * Miscellaneous Services:: Other services.
  307. Defining Services
  308. * Service Composition:: The model for composing services.
  309. * Service Types and Services:: Types and services.
  310. * Service Reference:: API reference.
  311. * Shepherd Services:: A particular type of service.
  312. Installing Debugging Files
  313. * Separate Debug Info:: Installing 'debug' outputs.
  314. * Rebuilding Debug Info:: Building missing debug info.
  315. Bootstrapping
  316. * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
  317. * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
  318. @end detailmenu
  319. @end menu
  320. @c *********************************************************************
  321. @node Introduction
  322. @chapter Introduction
  323. @cindex purpose
  324. GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
  325. using the international phonetic alphabet (IPA).} is a package
  326. management tool for and distribution of the GNU system.
  327. Guix makes it easy for unprivileged
  328. users to install, upgrade, or remove software packages, to roll back to a
  329. previous package set, to build packages from source, and generally
  330. assists with the creation and maintenance of software environments.
  331. @cindex Guix System
  332. @cindex GuixSD, now Guix System
  333. @cindex Guix System Distribution, now Guix System
  334. You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
  335. complements the available tools without interference (@pxref{Installation}),
  336. or you can use it as a standalone operating system distribution,
  337. @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
  338. System Distribution'' or ``GuixSD''. We now consider it makes more sense to
  339. group everything under the ``Guix'' banner since, after all, Guix System is
  340. readily available through the @command{guix system} command, even if you're
  341. using a different distro underneath!}. @xref{GNU Distribution}.
  342. @menu
  343. * Managing Software the Guix Way:: What's special.
  344. * GNU Distribution:: The packages and tools.
  345. @end menu
  346. @node Managing Software the Guix Way
  347. @section Managing Software the Guix Way
  348. @cindex user interfaces
  349. Guix provides a command-line package management interface
  350. (@pxref{Package Management}), tools to help with software development
  351. (@pxref{Development}), command-line utilities for more advanced usage
  352. (@pxref{Utilities}), as well as Scheme programming interfaces
  353. (@pxref{Programming Interface}).
  354. @cindex build daemon
  355. Its @dfn{build daemon} is responsible for building packages on behalf of
  356. users (@pxref{Setting Up the Daemon}) and for downloading pre-built
  357. binaries from authorized sources (@pxref{Substitutes}).
  358. @cindex extensibility of the distribution
  359. @cindex customization, of packages
  360. Guix includes package definitions for many GNU and non-GNU packages, all
  361. of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
  362. user's computing freedom}. It is @emph{extensible}: users can write
  363. their own package definitions (@pxref{Defining Packages}) and make them
  364. available as independent package modules (@pxref{Package Modules}). It
  365. is also @emph{customizable}: users can @emph{derive} specialized package
  366. definitions from existing ones, including from the command line
  367. (@pxref{Package Transformation Options}).
  368. @cindex functional package management
  369. @cindex isolation
  370. Under the hood, Guix implements the @dfn{functional package management}
  371. discipline pioneered by Nix (@pxref{Acknowledgments}).
  372. In Guix, the package build and installation process is seen
  373. as a @emph{function}, in the mathematical sense. That function takes inputs,
  374. such as build scripts, a compiler, and libraries, and
  375. returns an installed package. As a pure function, its result depends
  376. solely on its inputs---for instance, it cannot refer to software or
  377. scripts that were not explicitly passed as inputs. A build function
  378. always produces the same result when passed a given set of inputs. It
  379. cannot alter the environment of the running system in
  380. any way; for instance, it cannot create, modify, or delete files outside
  381. of its build and installation directories. This is achieved by running
  382. build processes in isolated environments (or @dfn{containers}), where only their
  383. explicit inputs are visible.
  384. @cindex store
  385. The result of package build functions is @dfn{cached} in the file
  386. system, in a special directory called @dfn{the store} (@pxref{The
  387. Store}). Each package is installed in a directory of its own in the
  388. store---by default under @file{/gnu/store}. The directory name contains
  389. a hash of all the inputs used to build that package; thus, changing an
  390. input yields a different directory name.
  391. This approach is the foundation for the salient features of Guix: support
  392. for transactional package upgrade and rollback, per-user installation, and
  393. garbage collection of packages (@pxref{Features}).
  394. @node GNU Distribution
  395. @section GNU Distribution
  396. @cindex Guix System
  397. Guix comes with a distribution of the GNU system consisting entirely of
  398. free software@footnote{The term ``free'' here refers to the
  399. @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
  400. users of that software}.}. The
  401. distribution can be installed on its own (@pxref{System Installation}),
  402. but it is also possible to install Guix as a package manager on top of
  403. an installed GNU/Linux system (@pxref{Installation}). When we need to
  404. distinguish between the two, we refer to the standalone distribution as
  405. Guix@tie{}System.
  406. The distribution provides core GNU packages such as GNU libc, GCC, and
  407. Binutils, as well as many GNU and non-GNU applications. The complete
  408. list of available packages can be browsed
  409. @url{https://www.gnu.org/software/guix/packages,on-line} or by
  410. running @command{guix package} (@pxref{Invoking guix package}):
  411. @example
  412. guix package --list-available
  413. @end example
  414. Our goal is to provide a practical 100% free software distribution of
  415. Linux-based and other variants of GNU, with a focus on the promotion and
  416. tight integration of GNU components, and an emphasis on programs and
  417. tools that help users exert that freedom.
  418. Packages are currently available on the following platforms:
  419. @table @code
  420. @item x86_64-linux
  421. Intel/AMD @code{x86_64} architecture, Linux-Libre kernel.
  422. @item i686-linux
  423. Intel 32-bit architecture (IA32), Linux-Libre kernel.
  424. @item armhf-linux
  425. ARMv7-A architecture with hard float, Thumb-2 and NEON,
  426. using the EABI hard-float application binary interface (ABI),
  427. and Linux-Libre kernel.
  428. @item aarch64-linux
  429. little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
  430. @item i586-gnu
  431. @uref{https://hurd.gnu.org, GNU/Hurd} on the Intel 32-bit architecture
  432. (IA32).
  433. This configuration is experimental and under development. The easiest
  434. way for you to give it a try is by setting up an instance of
  435. @code{hurd-vm-service-type} on your GNU/Linux machine
  436. (@pxref{transparent-emulation-qemu, @code{hurd-vm-service-type}}).
  437. @xref{Contributing}, on how to help!
  438. @item mips64el-linux (deprecated)
  439. little-endian 64-bit MIPS processors, specifically the Loongson series,
  440. n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
  441. supported; in particular, there is no ongoing work to ensure that this
  442. architecture still works. Should someone decide they wish to revive this
  443. architecture then the code is still available.
  444. @end table
  445. With Guix@tie{}System, you @emph{declare} all aspects of the operating system
  446. configuration and Guix takes care of instantiating the configuration in a
  447. transactional, reproducible, and stateless fashion (@pxref{System
  448. Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
  449. initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
  450. Manual}), the well-known GNU utilities and tool chain, as well as the
  451. graphical environment or system services of your choice.
  452. Guix System is available on all the above platforms except
  453. @code{mips64el-linux}.
  454. @noindent
  455. For information on porting to other architectures or kernels,
  456. @pxref{Porting}.
  457. Building this distribution is a cooperative effort, and you are invited
  458. to join! @xref{Contributing}, for information about how you can help.
  459. @c *********************************************************************
  460. @node Installation
  461. @chapter Installation
  462. @cindex installing Guix
  463. @quotation Note
  464. We recommend the use of this
  465. @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
  466. shell installer script} to install Guix on top of a running GNU/Linux system,
  467. thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
  468. with the installation of the package manager, which can be done on top of a
  469. running GNU/Linux system. If, instead, you want to install the complete GNU
  470. operating system, @pxref{System Installation}.} The script automates the
  471. download, installation, and initial configuration of Guix. It should be run
  472. as the root user.
  473. @end quotation
  474. @cindex foreign distro
  475. @cindex directories related to foreign distro
  476. When installed on a foreign distro, GNU@tie{}Guix complements the available
  477. tools without interference. Its data lives exclusively in two directories,
  478. usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
  479. such as @file{/etc}, are left untouched.
  480. Once installed, Guix can be updated by running @command{guix pull}
  481. (@pxref{Invoking guix pull}).
  482. If you prefer to perform the installation steps manually or want to tweak
  483. them, you may find the following subsections useful. They describe the
  484. software requirements of Guix, as well as how to install it manually and get
  485. ready to use it.
  486. @menu
  487. * Binary Installation:: Getting Guix running in no time!
  488. * Requirements:: Software needed to build and run Guix.
  489. * Running the Test Suite:: Testing Guix.
  490. * Setting Up the Daemon:: Preparing the build daemon's environment.
  491. * Invoking guix-daemon:: Running the build daemon.
  492. * Application Setup:: Application-specific setup.
  493. * Upgrading Guix:: Upgrading Guix and its build daemon.
  494. @end menu
  495. @node Binary Installation
  496. @section Binary Installation
  497. @cindex installing Guix from binaries
  498. @cindex installer script
  499. This section describes how to install Guix on an arbitrary system from a
  500. self-contained tarball providing binaries for Guix and for all its
  501. dependencies. This is often quicker than installing from source, which
  502. is described in the next sections. The only requirement is to have
  503. GNU@tie{}tar and Xz.
  504. @c Note duplicated from the ``Installation'' node.
  505. @quotation Note
  506. We recommend the use of this
  507. @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
  508. shell installer script}. The script automates the download, installation, and
  509. initial configuration steps described below. It should be run as the root
  510. user. As root, you can thus run this:
  511. @example
  512. cd /tmp
  513. wget https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh
  514. chmod +x guix-install.sh
  515. ./guix-install.sh
  516. @end example
  517. When you're done, @pxref{Application Setup} for extra configuration you
  518. might need, and @ref{Getting Started} for your first steps!
  519. @end quotation
  520. Installing goes along these lines:
  521. @enumerate
  522. @item
  523. @cindex downloading Guix binary
  524. Download the binary tarball from
  525. @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz},
  526. where @code{x86_64-linux} can be replaced with @code{i686-linux} for an
  527. @code{i686} (32-bits) machine already running the kernel Linux, and so on
  528. (@pxref{GNU Distribution}).
  529. @c The following is somewhat duplicated in ``System Installation''.
  530. Make sure to download the associated @file{.sig} file and to verify the
  531. authenticity of the tarball against it, along these lines:
  532. @example
  533. $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
  534. $ gpg --verify guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
  535. @end example
  536. If that command fails because you do not have the required public key,
  537. then run this command to import it:
  538. @example
  539. $ wget @value{OPENPGP-SIGNING-KEY-URL} \
  540. -qO - | gpg --import -
  541. @end example
  542. @noindent
  543. and rerun the @code{gpg --verify} command.
  544. Take note that a warning like ``This key is not certified with a trusted
  545. signature!'' is normal.
  546. @c end authentication part
  547. @item
  548. Now, you need to become the @code{root} user. Depending on your distribution,
  549. you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
  550. @example
  551. # cd /tmp
  552. # tar --warning=no-timestamp -xf \
  553. /path/to/guix-binary-@value{VERSION}.x86_64-linux.tar.xz
  554. # mv var/guix /var/ && mv gnu /
  555. @end example
  556. This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
  557. The latter contains a ready-to-use profile for @code{root} (see next
  558. step).
  559. Do @emph{not} unpack the tarball on a working Guix system since that
  560. would overwrite its own essential files.
  561. The @option{--warning=no-timestamp} option makes sure GNU@tie{}tar does
  562. not emit warnings about ``implausibly old time stamps'' (such
  563. warnings were triggered by GNU@tie{}tar 1.26 and older; recent
  564. versions are fine).
  565. They stem from the fact that all the
  566. files in the archive have their modification time set to 1 (which
  567. means January 1st, 1970). This is done on purpose to make sure the
  568. archive content is independent of its creation time, thus making it
  569. reproducible.
  570. @item
  571. Make the profile available under @file{~root/.config/guix/current}, which is
  572. where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
  573. @example
  574. # mkdir -p ~root/.config/guix
  575. # ln -sf /var/guix/profiles/per-user/root/current-guix \
  576. ~root/.config/guix/current
  577. @end example
  578. Source @file{etc/profile} to augment @env{PATH} and other relevant
  579. environment variables:
  580. @example
  581. # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
  582. source $GUIX_PROFILE/etc/profile
  583. @end example
  584. @item
  585. Create the group and user accounts for build users as explained below
  586. (@pxref{Build Environment Setup}).
  587. @item
  588. Run the daemon, and set it to automatically start on boot.
  589. If your host distro uses the systemd init system, this can be achieved
  590. with these commands:
  591. @c Versions of systemd that supported symlinked service files are not
  592. @c yet widely deployed, so we should suggest that users copy the service
  593. @c files into place.
  594. @c
  595. @c See this thread for more information:
  596. @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
  597. @example
  598. # cp ~root/.config/guix/current/lib/systemd/system/gnu-store.mount \
  599. ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
  600. /etc/systemd/system/
  601. # systemctl enable --now gnu-store.mount guix-daemon
  602. @end example
  603. If your host distro uses the Upstart init system:
  604. @example
  605. # initctl reload-configuration
  606. # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
  607. /etc/init/
  608. # start guix-daemon
  609. @end example
  610. Otherwise, you can still start the daemon manually with:
  611. @example
  612. # ~root/.config/guix/current/bin/guix-daemon \
  613. --build-users-group=guixbuild
  614. @end example
  615. @item
  616. Make the @command{guix} command available to other users on the machine,
  617. for instance with:
  618. @example
  619. # mkdir -p /usr/local/bin
  620. # cd /usr/local/bin
  621. # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
  622. @end example
  623. It is also a good idea to make the Info version of this manual available
  624. there:
  625. @example
  626. # mkdir -p /usr/local/share/info
  627. # cd /usr/local/share/info
  628. # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
  629. do ln -s $i ; done
  630. @end example
  631. That way, assuming @file{/usr/local/share/info} is in the search path,
  632. running @command{info guix} will open this manual (@pxref{Other Info
  633. Directories,,, texinfo, GNU Texinfo}, for more details on changing the
  634. Info search path).
  635. @item
  636. @cindex substitutes, authorization thereof
  637. To use substitutes from @code{@value{SUBSTITUTE-SERVER}} or one of its mirrors
  638. (@pxref{Substitutes}), authorize them:
  639. @example
  640. # guix archive --authorize < \
  641. ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER}.pub
  642. @end example
  643. @item
  644. Each user may need to perform a few additional steps to make their Guix
  645. environment ready for use, @pxref{Application Setup}.
  646. @end enumerate
  647. Voilà, the installation is complete!
  648. You can confirm that Guix is working by installing a sample package into
  649. the root profile:
  650. @example
  651. # guix install hello
  652. @end example
  653. The binary installation tarball can be (re)produced and verified simply
  654. by running the following command in the Guix source tree:
  655. @example
  656. make guix-binary.@var{system}.tar.xz
  657. @end example
  658. @noindent
  659. ...@: which, in turn, runs:
  660. @example
  661. guix pack -s @var{system} --localstatedir \
  662. --profile-name=current-guix guix
  663. @end example
  664. @xref{Invoking guix pack}, for more info on this handy tool.
  665. @node Requirements
  666. @section Requirements
  667. This section lists requirements when building Guix from source. The
  668. build procedure for Guix is the same as for other GNU software, and is
  669. not covered here. Please see the files @file{README} and @file{INSTALL}
  670. in the Guix source tree for additional details.
  671. @cindex official website
  672. GNU Guix is available for download from its website at
  673. @url{https://www.gnu.org/software/guix/}.
  674. GNU Guix depends on the following packages:
  675. @itemize
  676. @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x or
  677. 2.2.x;
  678. @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
  679. 0.1.0 or later;
  680. @item
  681. @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
  682. (@pxref{Guile Preparations, how to install the GnuTLS bindings for
  683. Guile,, gnutls-guile, GnuTLS-Guile});
  684. @item
  685. @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
  686. or later;
  687. @item @uref{https://notabug.org/guile-zlib/guile-zlib, Guile-zlib},
  688. version 0.1.0 or later;
  689. @item @uref{https://notabug.org/guile-lzlib/guile-lzlib, Guile-lzlib};
  690. @item @uref{https://www.nongnu.org/guile-avahi/, Guile-Avahi};
  691. @item
  692. @c FIXME: Specify a version number once a release has been made.
  693. @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, version 0.3.0
  694. or later;
  695. @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON}
  696. 4.3.0 or later;
  697. @item @url{https://www.gnu.org/software/make/, GNU Make}.
  698. @end itemize
  699. The following dependencies are optional:
  700. @itemize
  701. @item
  702. @c Note: We need at least 0.13.0 for #:nodelay.
  703. Support for build offloading (@pxref{Daemon Offload Setup}) and
  704. @command{guix copy} (@pxref{Invoking guix copy}) depends on
  705. @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
  706. version 0.13.0 or later.
  707. @item
  708. @uref{https://notabug.org/guile-zstd/guile-zstd, Guile-zstd}, for zstd
  709. compression and decompression in @command{guix publish} and for
  710. substitutes (@pxref{Invoking guix publish}).
  711. @item
  712. @uref{https://ngyro.com/software/guile-semver.html, Guile-Semver} for
  713. the @code{crate} importer (@pxref{Invoking guix import}).
  714. @item
  715. @uref{https://www.nongnu.org/guile-lib/doc/ref/htmlprag/, Guile-Lib} for
  716. the @code{go} importer (@pxref{Invoking guix import}) and for some of
  717. the ``updaters'' (@pxref{Invoking guix refresh}).
  718. @item
  719. When @url{http://www.bzip.org, libbz2} is available,
  720. @command{guix-daemon} can use it to compress build logs.
  721. @end itemize
  722. Unless @option{--disable-daemon} was passed to @command{configure}, the
  723. following packages are also needed:
  724. @itemize
  725. @item @url{https://gnupg.org/, GNU libgcrypt};
  726. @item @url{https://sqlite.org, SQLite 3};
  727. @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
  728. C++11 standard.
  729. @end itemize
  730. @cindex state directory
  731. When configuring Guix on a system that already has a Guix installation,
  732. be sure to specify the same state directory as the existing installation
  733. using the @option{--localstatedir} option of the @command{configure}
  734. script (@pxref{Directory Variables, @code{localstatedir},, standards,
  735. GNU Coding Standards}). Usually, this @var{localstatedir} option is
  736. set to the value @file{/var}. The @command{configure} script protects
  737. against unintended misconfiguration of @var{localstatedir} so you do not
  738. inadvertently corrupt your store (@pxref{The Store}).
  739. @node Running the Test Suite
  740. @section Running the Test Suite
  741. @cindex test suite
  742. After a successful @command{configure} and @code{make} run, it is a good
  743. idea to run the test suite. It can help catch issues with the setup or
  744. environment, or bugs in Guix itself---and really, reporting test
  745. failures is a good way to help improve the software. To run the test
  746. suite, type:
  747. @example
  748. make check
  749. @end example
  750. Test cases can run in parallel: you can use the @code{-j} option of
  751. GNU@tie{}make to speed things up. The first run may take a few minutes
  752. on a recent machine; subsequent runs will be faster because the store
  753. that is created for test purposes will already have various things in
  754. cache.
  755. It is also possible to run a subset of the tests by defining the
  756. @code{TESTS} makefile variable as in this example:
  757. @example
  758. make check TESTS="tests/store.scm tests/cpio.scm"
  759. @end example
  760. By default, tests results are displayed at a file level. In order to
  761. see the details of every individual test cases, it is possible to define
  762. the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
  763. @example
  764. make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
  765. @end example
  766. The underlying SRFI 64 custom Automake test driver used for the 'check'
  767. test suite (located at @file{build-aux/test-driver.scm}) also allows
  768. selecting which test cases to run at a finer level, via its
  769. @option{--select} and @option{--exclude} options. Here's an example, to
  770. run all the test cases from the @file{tests/packages.scm} test file
  771. whose names start with ``transaction-upgrade-entry'':
  772. @example
  773. export SCM_LOG_DRIVER_FLAGS="--select=^transaction-upgrade-entry"
  774. make check TESTS="tests/packages.scm"
  775. @end example
  776. Those wishing to inspect the results of failed tests directly from the
  777. command line can add the @option{--errors-only=yes} option to the
  778. @code{SCM_LOG_DRIVER_FLAGS} makefile variable and set the @code{VERBOSE}
  779. Automake makefile variable, as in:
  780. @example
  781. make check SCM_LOG_DRIVER_FLAGS="--brief=no --errors-only=yes" VERBOSE=1
  782. @end example
  783. The @option{--show-duration=yes} option can be used to print the
  784. duration of the individual test cases, when used in combination with
  785. @option{--brief=no}:
  786. @example
  787. make check SCM_LOG_DRIVER_FLAGS="--brief=no --show-duration=yes"
  788. @end example
  789. @xref{Parallel Test Harness,,,automake,GNU Automake} for more
  790. information about the Automake Parallel Test Harness.
  791. Upon failure, please email @email{bug-guix@@gnu.org} and attach the
  792. @file{test-suite.log} file. Please specify the Guix version being used
  793. as well as version numbers of the dependencies (@pxref{Requirements}) in
  794. your message.
  795. Guix also comes with a whole-system test suite that tests complete
  796. Guix System instances. It can only run on systems where
  797. Guix is already installed, using:
  798. @example
  799. make check-system
  800. @end example
  801. @noindent
  802. or, again, by defining @code{TESTS} to select a subset of tests to run:
  803. @example
  804. make check-system TESTS="basic mcron"
  805. @end example
  806. These system tests are defined in the @code{(gnu tests @dots{})}
  807. modules. They work by running the operating systems under test with
  808. lightweight instrumentation in a virtual machine (VM). They can be
  809. computationally intensive or rather cheap, depending on whether
  810. substitutes are available for their dependencies (@pxref{Substitutes}).
  811. Some of them require a lot of storage space to hold VM images.
  812. Again in case of test failures, please send @email{bug-guix@@gnu.org}
  813. all the details.
  814. @node Setting Up the Daemon
  815. @section Setting Up the Daemon
  816. @cindex daemon
  817. Operations such as building a package or running the garbage collector
  818. are all performed by a specialized process, the @dfn{build daemon}, on
  819. behalf of clients. Only the daemon may access the store and its
  820. associated database. Thus, any operation that manipulates the store
  821. goes through the daemon. For instance, command-line tools such as
  822. @command{guix package} and @command{guix build} communicate with the
  823. daemon (@i{via} remote procedure calls) to instruct it what to do.
  824. The following sections explain how to prepare the build daemon's
  825. environment. See also @ref{Substitutes}, for information on how to allow
  826. the daemon to download pre-built binaries.
  827. @menu
  828. * Build Environment Setup:: Preparing the isolated build environment.
  829. * Daemon Offload Setup:: Offloading builds to remote machines.
  830. * SELinux Support:: Using an SELinux policy for the daemon.
  831. @end menu
  832. @node Build Environment Setup
  833. @subsection Build Environment Setup
  834. @cindex build environment
  835. In a standard multi-user setup, Guix and its daemon---the
  836. @command{guix-daemon} program---are installed by the system
  837. administrator; @file{/gnu/store} is owned by @code{root} and
  838. @command{guix-daemon} runs as @code{root}. Unprivileged users may use
  839. Guix tools to build packages or otherwise access the store, and the
  840. daemon will do it on their behalf, ensuring that the store is kept in a
  841. consistent state, and allowing built packages to be shared among users.
  842. @cindex build users
  843. When @command{guix-daemon} runs as @code{root}, you may not want package
  844. build processes themselves to run as @code{root} too, for obvious
  845. security reasons. To avoid that, a special pool of @dfn{build users}
  846. should be created for use by build processes started by the daemon.
  847. These build users need not have a shell and a home directory: they will
  848. just be used when the daemon drops @code{root} privileges in build
  849. processes. Having several such users allows the daemon to launch
  850. distinct build processes under separate UIDs, which guarantees that they
  851. do not interfere with each other---an essential feature since builds are
  852. regarded as pure functions (@pxref{Introduction}).
  853. On a GNU/Linux system, a build user pool may be created like this (using
  854. Bash syntax and the @code{shadow} commands):
  855. @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
  856. @c for why `-G' is needed.
  857. @example
  858. # groupadd --system guixbuild
  859. # for i in `seq -w 1 10`;
  860. do
  861. useradd -g guixbuild -G guixbuild \
  862. -d /var/empty -s `which nologin` \
  863. -c "Guix build user $i" --system \
  864. guixbuilder$i;
  865. done
  866. @end example
  867. @noindent
  868. The number of build users determines how many build jobs may run in
  869. parallel, as specified by the @option{--max-jobs} option
  870. (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
  871. @command{guix system vm} and related commands, you may need to add the
  872. build users to the @code{kvm} group so they can access @file{/dev/kvm},
  873. using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
  874. (@pxref{Invoking guix system}).
  875. The @code{guix-daemon} program may then be run as @code{root} with the
  876. following command@footnote{If your machine uses the systemd init system,
  877. dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
  878. file in @file{/etc/systemd/system} will ensure that
  879. @command{guix-daemon} is automatically started. Similarly, if your
  880. machine uses the Upstart init system, drop the
  881. @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
  882. file in @file{/etc/init}.}:
  883. @example
  884. # guix-daemon --build-users-group=guixbuild
  885. @end example
  886. @cindex chroot
  887. @noindent
  888. This way, the daemon starts build processes in a chroot, under one of
  889. the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
  890. environment contains nothing but:
  891. @c Keep this list in sync with libstore/build.cc! -----------------------
  892. @itemize
  893. @item
  894. a minimal @code{/dev} directory, created mostly independently from the
  895. host @code{/dev}@footnote{``Mostly'', because while the set of files
  896. that appear in the chroot's @code{/dev} is fixed, most of these files
  897. can only be created if the host has them.};
  898. @item
  899. the @code{/proc} directory; it only shows the processes of the container
  900. since a separate PID name space is used;
  901. @item
  902. @file{/etc/passwd} with an entry for the current user and an entry for
  903. user @file{nobody};
  904. @item
  905. @file{/etc/group} with an entry for the user's group;
  906. @item
  907. @file{/etc/hosts} with an entry that maps @code{localhost} to
  908. @code{127.0.0.1};
  909. @item
  910. a writable @file{/tmp} directory.
  911. @end itemize
  912. You can influence the directory where the daemon stores build trees
  913. @i{via} the @env{TMPDIR} environment variable. However, the build tree
  914. within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
  915. where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
  916. This way, the value of @env{TMPDIR} does not leak inside build
  917. environments, which avoids discrepancies in cases where build processes
  918. capture the name of their build tree.
  919. @vindex http_proxy
  920. @vindex https_proxy
  921. The daemon also honors the @env{http_proxy} and @env{https_proxy}
  922. environment variables for HTTP and HTTPS downloads it performs, be it
  923. for fixed-output derivations (@pxref{Derivations}) or for substitutes
  924. (@pxref{Substitutes}).
  925. If you are installing Guix as an unprivileged user, it is still possible
  926. to run @command{guix-daemon} provided you pass @option{--disable-chroot}.
  927. However, build processes will not be isolated from one another, and not
  928. from the rest of the system. Thus, build processes may interfere with
  929. each other, and may access programs, libraries, and other files
  930. available on the system---making it much harder to view them as
  931. @emph{pure} functions.
  932. @node Daemon Offload Setup
  933. @subsection Using the Offload Facility
  934. @cindex offloading
  935. @cindex build hook
  936. When desired, the build daemon can @dfn{offload} derivation builds to
  937. other machines running Guix, using the @code{offload} @dfn{build
  938. hook}@footnote{This feature is available only when
  939. @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
  940. present.}. When that feature is enabled, a list of user-specified build
  941. machines is read from @file{/etc/guix/machines.scm}; every time a build
  942. is requested, for instance via @code{guix build}, the daemon attempts to
  943. offload it to one of the machines that satisfy the constraints of the
  944. derivation, in particular its system types---e.g., @code{x86_64-linux}.
  945. A single machine can have multiple system types, either because its
  946. architecture natively supports it, via emulation
  947. (@pxref{transparent-emulation-qemu, Transparent Emulation with QEMU}),
  948. or both. Missing prerequisites for the build are
  949. copied over SSH to the target machine, which then proceeds with the
  950. build; upon success the output(s) of the build are copied back to the
  951. initial machine. The offload facility comes with a basic scheduler that
  952. attempts to select the best machine. The best machine is chosen among
  953. the available machines based on criteria such as:
  954. @enumerate
  955. @item
  956. The availability of a build slot. A build machine can have as many
  957. build slots (connections) as the value of the @code{parallel-builds}
  958. field of its @code{build-machine} object.
  959. @item
  960. Its relative speed, as defined via the @code{speed} field of its
  961. @code{build-machine} object.
  962. @item
  963. Its load. The normalized machine load must be lower than a threshold
  964. value, configurable via the @code{overload-threshold} field of its
  965. @code{build-machine} object.
  966. @item
  967. Disk space availability. More than a 100 MiB must be available.
  968. @end enumerate
  969. The @file{/etc/guix/machines.scm} file typically looks like this:
  970. @lisp
  971. (list (build-machine
  972. (name "eightysix.example.org")
  973. (systems (list "x86_64-linux" "i686-linux"))
  974. (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
  975. (user "bob")
  976. (speed 2.)) ;incredibly fast!
  977. (build-machine
  978. (name "armeight.example.org")
  979. (systems (list "aarch64-linux"))
  980. (host-key "ssh-rsa AAAAB3Nza@dots{}")
  981. (user "alice")
  982. (private-key
  983. (string-append (getenv "HOME")
  984. "/.ssh/identity-for-guix"))))
  985. @end lisp
  986. @noindent
  987. In the example above we specify a list of two build machines, one for
  988. the @code{x86_64} and @code{i686} architectures and one for the
  989. @code{aarch64} architecture.
  990. In fact, this file is---not surprisingly!---a Scheme file that is
  991. evaluated when the @code{offload} hook is started. Its return value
  992. must be a list of @code{build-machine} objects. While this example
  993. shows a fixed list of build machines, one could imagine, say, using
  994. DNS-SD to return a list of potential build machines discovered in the
  995. local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
  996. Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
  997. detailed below.
  998. @deftp {Data Type} build-machine
  999. This data type represents build machines to which the daemon may offload
  1000. builds. The important fields are:
  1001. @table @code
  1002. @item name
  1003. The host name of the remote machine.
  1004. @item systems
  1005. The system types the remote machine supports---e.g., @code{(list
  1006. "x86_64-linux" "i686-linux")}.
  1007. @item user
  1008. The user account to use when connecting to the remote machine over SSH.
  1009. Note that the SSH key pair must @emph{not} be passphrase-protected, to
  1010. allow non-interactive logins.
  1011. @item host-key
  1012. This must be the machine's SSH @dfn{public host key} in OpenSSH format.
  1013. This is used to authenticate the machine when we connect to it. It is a
  1014. long string that looks like this:
  1015. @example
  1016. ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
  1017. @end example
  1018. If the machine is running the OpenSSH daemon, @command{sshd}, the host
  1019. key can be found in a file such as
  1020. @file{/etc/ssh/ssh_host_ed25519_key.pub}.
  1021. If the machine is running the SSH daemon of GNU@tie{}lsh,
  1022. @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
  1023. similar file. It can be converted to the OpenSSH format using
  1024. @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
  1025. @example
  1026. $ lsh-export-key --openssh < /etc/lsh/host-key.pub
  1027. ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
  1028. @end example
  1029. @end table
  1030. A number of optional fields may be specified:
  1031. @table @asis
  1032. @item @code{port} (default: @code{22})
  1033. Port number of SSH server on the machine.
  1034. @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
  1035. The SSH private key file to use when connecting to the machine, in
  1036. OpenSSH format. This key must not be protected with a passphrase.
  1037. Note that the default value is the private key @emph{of the root
  1038. account}. Make sure it exists if you use the default.
  1039. @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
  1040. @itemx @code{compression-level} (default: @code{3})
  1041. The SSH-level compression methods and compression level requested.
  1042. Note that offloading relies on SSH compression to reduce bandwidth usage
  1043. when transferring files to and from build machines.
  1044. @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
  1045. File name of the Unix-domain socket @command{guix-daemon} is listening
  1046. to on that machine.
  1047. @item @code{overload-threshold} (default: @code{0.6})
  1048. The load threshold above which a potential offload machine is
  1049. disregarded by the offload scheduler. The value roughly translates to
  1050. the total processor usage of the build machine, ranging from 0.0 (0%) to
  1051. 1.0 (100%). It can also be disabled by setting
  1052. @code{overload-threshold} to @code{#f}.
  1053. @item @code{parallel-builds} (default: @code{1})
  1054. The number of builds that may run in parallel on the machine.
  1055. @item @code{speed} (default: @code{1.0})
  1056. A ``relative speed factor''. The offload scheduler will tend to prefer
  1057. machines with a higher speed factor.
  1058. @item @code{features} (default: @code{'()})
  1059. A list of strings denoting specific features supported by the machine.
  1060. An example is @code{"kvm"} for machines that have the KVM Linux modules
  1061. and corresponding hardware support. Derivations can request features by
  1062. name, and they will be scheduled on matching build machines.
  1063. @end table
  1064. @end deftp
  1065. The @command{guix} command must be in the search path on the build
  1066. machines. You can check whether this is the case by running:
  1067. @example
  1068. ssh build-machine guix repl --version
  1069. @end example
  1070. There is one last thing to do once @file{machines.scm} is in place. As
  1071. explained above, when offloading, files are transferred back and forth
  1072. between the machine stores. For this to work, you first need to
  1073. generate a key pair on each machine to allow the daemon to export signed
  1074. archives of files from the store (@pxref{Invoking guix archive}):
  1075. @example
  1076. # guix archive --generate-key
  1077. @end example
  1078. @noindent
  1079. Each build machine must authorize the key of the master machine so that
  1080. it accepts store items it receives from the master:
  1081. @example
  1082. # guix archive --authorize < master-public-key.txt
  1083. @end example
  1084. @noindent
  1085. Likewise, the master machine must authorize the key of each build machine.
  1086. All the fuss with keys is here to express pairwise mutual trust
  1087. relations between the master and the build machines. Concretely, when
  1088. the master receives files from a build machine (and @i{vice versa}), its
  1089. build daemon can make sure they are genuine, have not been tampered
  1090. with, and that they are signed by an authorized key.
  1091. @cindex offload test
  1092. To test whether your setup is operational, run this command on the
  1093. master node:
  1094. @example
  1095. # guix offload test
  1096. @end example
  1097. This will attempt to connect to each of the build machines specified in
  1098. @file{/etc/guix/machines.scm}, make sure Guix is
  1099. available on each machine, attempt to export to the machine and import
  1100. from it, and report any error in the process.
  1101. If you want to test a different machine file, just specify it on the
  1102. command line:
  1103. @example
  1104. # guix offload test machines-qualif.scm
  1105. @end example
  1106. Last, you can test the subset of the machines whose name matches a
  1107. regular expression like this:
  1108. @example
  1109. # guix offload test machines.scm '\.gnu\.org$'
  1110. @end example
  1111. @cindex offload status
  1112. To display the current load of all build hosts, run this command on the
  1113. main node:
  1114. @example
  1115. # guix offload status
  1116. @end example
  1117. @node SELinux Support
  1118. @subsection SELinux Support
  1119. @cindex SELinux, daemon policy
  1120. @cindex mandatory access control, SELinux
  1121. @cindex security, guix-daemon
  1122. Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
  1123. can be installed on a system where SELinux is enabled, in order to label
  1124. Guix files and to specify the expected behavior of the daemon. Since
  1125. Guix System does not provide an SELinux base policy, the daemon policy cannot
  1126. be used on Guix System.
  1127. @subsubsection Installing the SELinux policy
  1128. @cindex SELinux, policy installation
  1129. To install the policy run this command as root:
  1130. @example
  1131. semodule -i etc/guix-daemon.cil
  1132. @end example
  1133. Then relabel the file system with @code{restorecon} or by a different
  1134. mechanism provided by your system.
  1135. Once the policy is installed, the file system has been relabeled, and
  1136. the daemon has been restarted, it should be running in the
  1137. @code{guix_daemon_t} context. You can confirm this with the following
  1138. command:
  1139. @example
  1140. ps -Zax | grep guix-daemon
  1141. @end example
  1142. Monitor the SELinux log files as you run a command like @code{guix build
  1143. hello} to convince yourself that SELinux permits all necessary
  1144. operations.
  1145. @subsubsection Limitations
  1146. @cindex SELinux, limitations
  1147. This policy is not perfect. Here is a list of limitations or quirks
  1148. that should be considered when deploying the provided SELinux policy for
  1149. the Guix daemon.
  1150. @enumerate
  1151. @item
  1152. @code{guix_daemon_socket_t} isn’t actually used. None of the socket
  1153. operations involve contexts that have anything to do with
  1154. @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
  1155. but it would be preferrable to define socket rules for only this label.
  1156. @item
  1157. @code{guix gc} cannot access arbitrary links to profiles. By design,
  1158. the file label of the destination of a symlink is independent of the
  1159. file label of the link itself. Although all profiles under
  1160. $localstatedir are labelled, the links to these profiles inherit the
  1161. label of the directory they are in. For links in the user’s home
  1162. directory this will be @code{user_home_t}. But for links from the root
  1163. user’s home directory, or @file{/tmp}, or the HTTP server’s working
  1164. directory, etc, this won’t work. @code{guix gc} would be prevented from
  1165. reading and following these links.
  1166. @item
  1167. The daemon’s feature to listen for TCP connections might no longer work.
  1168. This might require extra rules, because SELinux treats network sockets
  1169. differently from files.
  1170. @item
  1171. Currently all files with a name matching the regular expression
  1172. @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
  1173. label @code{guix_daemon_exec_t}; this means that @emph{any} file with
  1174. that name in any profile would be permitted to run in the
  1175. @code{guix_daemon_t} domain. This is not ideal. An attacker could
  1176. build a package that provides this executable and convince a user to
  1177. install and run it, which lifts it into the @code{guix_daemon_t} domain.
  1178. At that point SELinux could not prevent it from accessing files that are
  1179. allowed for processes in that domain.
  1180. You will need to relabel the store directory after all upgrades to
  1181. @file{guix-daemon}, such as after running @code{guix pull}. Assuming the
  1182. store is in @file{/gnu}, you can do this with @code{restorecon -vR /gnu},
  1183. or by other means provided by your operating system.
  1184. We could generate a much more restrictive policy at installation time,
  1185. so that only the @emph{exact} file name of the currently installed
  1186. @code{guix-daemon} executable would be labelled with
  1187. @code{guix_daemon_exec_t}, instead of using a broad regular expression.
  1188. The downside is that root would have to install or upgrade the policy at
  1189. installation time whenever the Guix package that provides the
  1190. effectively running @code{guix-daemon} executable is upgraded.
  1191. @end enumerate
  1192. @node Invoking guix-daemon
  1193. @section Invoking @command{guix-daemon}
  1194. The @command{guix-daemon} program implements all the functionality to
  1195. access the store. This includes launching build processes, running the
  1196. garbage collector, querying the availability of a build result, etc. It
  1197. is normally run as @code{root} like this:
  1198. @example
  1199. # guix-daemon --build-users-group=guixbuild
  1200. @end example
  1201. @noindent
  1202. For details on how to set it up, @pxref{Setting Up the Daemon}.
  1203. @cindex chroot
  1204. @cindex container, build environment
  1205. @cindex build environment
  1206. @cindex reproducible builds
  1207. By default, @command{guix-daemon} launches build processes under
  1208. different UIDs, taken from the build group specified with
  1209. @option{--build-users-group}. In addition, each build process is run in a
  1210. chroot environment that only contains the subset of the store that the
  1211. build process depends on, as specified by its derivation
  1212. (@pxref{Programming Interface, derivation}), plus a set of specific
  1213. system directories. By default, the latter contains @file{/dev} and
  1214. @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
  1215. @dfn{container}: in addition to having its own file system tree, it has
  1216. a separate mount name space, its own PID name space, network name space,
  1217. etc. This helps achieve reproducible builds (@pxref{Features}).
  1218. When the daemon performs a build on behalf of the user, it creates a
  1219. build directory under @file{/tmp} or under the directory specified by
  1220. its @env{TMPDIR} environment variable. This directory is shared with
  1221. the container for the duration of the build, though within the container,
  1222. the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
  1223. The build directory is automatically deleted upon completion, unless the
  1224. build failed and the client specified @option{--keep-failed}
  1225. (@pxref{Common Build Options, @option{--keep-failed}}).
  1226. The daemon listens for connections and spawns one sub-process for each session
  1227. started by a client (one of the @command{guix} sub-commands). The
  1228. @command{guix processes} command allows you to get an overview of the activity
  1229. on your system by viewing each of the active sessions and clients.
  1230. @xref{Invoking guix processes}, for more information.
  1231. The following command-line options are supported:
  1232. @table @code
  1233. @item --build-users-group=@var{group}
  1234. Take users from @var{group} to run build processes (@pxref{Setting Up
  1235. the Daemon, build users}).
  1236. @item --no-substitutes
  1237. @cindex substitutes
  1238. Do not use substitutes for build products. That is, always build things
  1239. locally instead of allowing downloads of pre-built binaries
  1240. (@pxref{Substitutes}).
  1241. When the daemon runs with @option{--no-substitutes}, clients can still
  1242. explicitly enable substitution @i{via} the @code{set-build-options}
  1243. remote procedure call (@pxref{The Store}).
  1244. @anchor{daemon-substitute-urls}
  1245. @item --substitute-urls=@var{urls}
  1246. Consider @var{urls} the default whitespace-separated list of substitute
  1247. source URLs. When this option is omitted,
  1248. @indicateurl{https://@value{SUBSTITUTE-SERVER}} is used.
  1249. This means that substitutes may be downloaded from @var{urls}, as long
  1250. as they are signed by a trusted signature (@pxref{Substitutes}).
  1251. @xref{Getting Substitutes from Other Servers}, for more information on
  1252. how to configure the daemon to get substitutes from other servers.
  1253. @cindex offloading
  1254. @item --no-offload
  1255. Do not use offload builds to other machines (@pxref{Daemon Offload
  1256. Setup}). That is, always build things locally instead of offloading
  1257. builds to remote machines.
  1258. @item --cache-failures
  1259. Cache build failures. By default, only successful builds are cached.
  1260. When this option is used, @command{guix gc --list-failures} can be used
  1261. to query the set of store items marked as failed; @command{guix gc
  1262. --clear-failures} removes store items from the set of cached failures.
  1263. @xref{Invoking guix gc}.
  1264. @item --cores=@var{n}
  1265. @itemx -c @var{n}
  1266. Use @var{n} CPU cores to build each derivation; @code{0} means as many
  1267. as available.
  1268. The default value is @code{0}, but it may be overridden by clients, such
  1269. as the @option{--cores} option of @command{guix build} (@pxref{Invoking
  1270. guix build}).
  1271. The effect is to define the @env{NIX_BUILD_CORES} environment variable
  1272. in the build process, which can then use it to exploit internal
  1273. parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
  1274. @item --max-jobs=@var{n}
  1275. @itemx -M @var{n}
  1276. Allow at most @var{n} build jobs in parallel. The default value is
  1277. @code{1}. Setting it to @code{0} means that no builds will be performed
  1278. locally; instead, the daemon will offload builds (@pxref{Daemon Offload
  1279. Setup}), or simply fail.
  1280. @item --max-silent-time=@var{seconds}
  1281. When the build or substitution process remains silent for more than
  1282. @var{seconds}, terminate it and report a build failure.
  1283. The default value is @code{0}, which disables the timeout.
  1284. The value specified here can be overridden by clients (@pxref{Common
  1285. Build Options, @option{--max-silent-time}}).
  1286. @item --timeout=@var{seconds}
  1287. Likewise, when the build or substitution process lasts for more than
  1288. @var{seconds}, terminate it and report a build failure.
  1289. The default value is @code{0}, which disables the timeout.
  1290. The value specified here can be overridden by clients (@pxref{Common
  1291. Build Options, @option{--timeout}}).
  1292. @item --rounds=@var{N}
  1293. Build each derivation @var{n} times in a row, and raise an error if
  1294. consecutive build results are not bit-for-bit identical. Note that this
  1295. setting can be overridden by clients such as @command{guix build}
  1296. (@pxref{Invoking guix build}).
  1297. When used in conjunction with @option{--keep-failed}, the differing
  1298. output is kept in the store, under @file{/gnu/store/@dots{}-check}.
  1299. This makes it easy to look for differences between the two results.
  1300. @item --debug
  1301. Produce debugging output.
  1302. This is useful to debug daemon start-up issues, but then it may be
  1303. overridden by clients, for example the @option{--verbosity} option of
  1304. @command{guix build} (@pxref{Invoking guix build}).
  1305. @item --chroot-directory=@var{dir}
  1306. Add @var{dir} to the build chroot.
  1307. Doing this may change the result of build processes---for instance if
  1308. they use optional dependencies found in @var{dir} when it is available,
  1309. and not otherwise. For that reason, it is not recommended to do so.
  1310. Instead, make sure that each derivation declares all the inputs that it
  1311. needs.
  1312. @item --disable-chroot
  1313. Disable chroot builds.
  1314. Using this option is not recommended since, again, it would allow build
  1315. processes to gain access to undeclared dependencies. It is necessary,
  1316. though, when @command{guix-daemon} is running under an unprivileged user
  1317. account.
  1318. @item --log-compression=@var{type}
  1319. Compress build logs according to @var{type}, one of @code{gzip},
  1320. @code{bzip2}, or @code{none}.
  1321. Unless @option{--lose-logs} is used, all the build logs are kept in the
  1322. @var{localstatedir}. To save space, the daemon automatically compresses
  1323. them with Bzip2 by default.
  1324. @item --discover[=yes|no]
  1325. Whether to discover substitute servers on the local network using mDNS
  1326. and DNS-SD.
  1327. This feature is still experimental. However, here are a few
  1328. considerations.
  1329. @enumerate
  1330. @item
  1331. It might be faster/less expensive than fetching from remote servers;
  1332. @item
  1333. There are no security risks, only genuine substitutes will be used
  1334. (@pxref{Substitute Authentication});
  1335. @item
  1336. An attacker advertising @command{guix publish} on your LAN cannot serve
  1337. you malicious binaries, but they can learn what software you’re
  1338. installing;
  1339. @item
  1340. Servers may serve substitute over HTTP, unencrypted, so anyone on the
  1341. LAN can see what software you’re installing.
  1342. @end enumerate
  1343. It is also possible to enable or disable substitute server discovery at
  1344. run-time by running:
  1345. @example
  1346. herd discover guix-daemon on
  1347. herd discover guix-daemon off
  1348. @end example
  1349. @item --disable-deduplication
  1350. @cindex deduplication
  1351. Disable automatic file ``deduplication'' in the store.
  1352. By default, files added to the store are automatically ``deduplicated'':
  1353. if a newly added file is identical to another one found in the store,
  1354. the daemon makes the new file a hard link to the other file. This can
  1355. noticeably reduce disk usage, at the expense of slightly increased
  1356. input/output load at the end of a build process. This option disables
  1357. this optimization.
  1358. @item --gc-keep-outputs[=yes|no]
  1359. Tell whether the garbage collector (GC) must keep outputs of live
  1360. derivations.
  1361. @cindex GC roots
  1362. @cindex garbage collector roots
  1363. When set to @code{yes}, the GC will keep the outputs of any live
  1364. derivation available in the store---the @file{.drv} files. The default
  1365. is @code{no}, meaning that derivation outputs are kept only if they are
  1366. reachable from a GC root. @xref{Invoking guix gc}, for more on GC
  1367. roots.
  1368. @item --gc-keep-derivations[=yes|no]
  1369. Tell whether the garbage collector (GC) must keep derivations
  1370. corresponding to live outputs.
  1371. When set to @code{yes}, as is the case by default, the GC keeps
  1372. derivations---i.e., @file{.drv} files---as long as at least one of their
  1373. outputs is live. This allows users to keep track of the origins of
  1374. items in their store. Setting it to @code{no} saves a bit of disk
  1375. space.
  1376. In this way, setting @option{--gc-keep-derivations} to @code{yes} causes
  1377. liveness to flow from outputs to derivations, and setting
  1378. @option{--gc-keep-outputs} to @code{yes} causes liveness to flow from
  1379. derivations to outputs. When both are set to @code{yes}, the effect is
  1380. to keep all the build prerequisites (the sources, compiler, libraries,
  1381. and other build-time tools) of live objects in the store, regardless of
  1382. whether these prerequisites are reachable from a GC root. This is
  1383. convenient for developers since it saves rebuilds or downloads.
  1384. @item --impersonate-linux-2.6
  1385. On Linux-based systems, impersonate Linux 2.6. This means that the
  1386. kernel's @command{uname} system call will report 2.6 as the release number.
  1387. This might be helpful to build programs that (usually wrongfully) depend
  1388. on the kernel version number.
  1389. @item --lose-logs
  1390. Do not keep build logs. By default they are kept under
  1391. @file{@var{localstatedir}/guix/log}.
  1392. @item --system=@var{system}
  1393. Assume @var{system} as the current system type. By default it is the
  1394. architecture/kernel pair found at configure time, such as
  1395. @code{x86_64-linux}.
  1396. @item --listen=@var{endpoint}
  1397. Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
  1398. as the file name of a Unix-domain socket if it starts with
  1399. @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
  1400. host name or host name and port to listen to. Here are a few examples:
  1401. @table @code
  1402. @item --listen=/gnu/var/daemon
  1403. Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
  1404. creating it if needed.
  1405. @item --listen=localhost
  1406. @cindex daemon, remote access
  1407. @cindex remote access to the daemon
  1408. @cindex daemon, cluster setup
  1409. @cindex clusters, daemon setup
  1410. Listen for TCP connections on the network interface corresponding to
  1411. @code{localhost}, on port 44146.
  1412. @item --listen=128.0.0.42:1234
  1413. Listen for TCP connections on the network interface corresponding to
  1414. @code{128.0.0.42}, on port 1234.
  1415. @end table
  1416. This option can be repeated multiple times, in which case
  1417. @command{guix-daemon} accepts connections on all the specified
  1418. endpoints. Users can tell client commands what endpoint to connect to
  1419. by setting the @env{GUIX_DAEMON_SOCKET} environment variable
  1420. (@pxref{The Store, @env{GUIX_DAEMON_SOCKET}}).
  1421. @quotation Note
  1422. The daemon protocol is @emph{unauthenticated and unencrypted}. Using
  1423. @option{--listen=@var{host}} is suitable on local networks, such as
  1424. clusters, where only trusted nodes may connect to the build daemon. In
  1425. other cases where remote access to the daemon is needed, we recommend
  1426. using Unix-domain sockets along with SSH.
  1427. @end quotation
  1428. When @option{--listen} is omitted, @command{guix-daemon} listens for
  1429. connections on the Unix-domain socket located at
  1430. @file{@var{localstatedir}/guix/daemon-socket/socket}.
  1431. @end table
  1432. @node Application Setup
  1433. @section Application Setup
  1434. @cindex foreign distro
  1435. When using Guix on top of GNU/Linux distribution other than Guix System---a
  1436. so-called @dfn{foreign distro}---a few additional steps are needed to
  1437. get everything in place. Here are some of them.
  1438. @subsection Locales
  1439. @anchor{locales-and-locpath}
  1440. @cindex locales, when not on Guix System
  1441. @vindex LOCPATH
  1442. @vindex GUIX_LOCPATH
  1443. Packages installed @i{via} Guix will not use the locale data of the
  1444. host system. Instead, you must first install one of the locale packages
  1445. available with Guix and then define the @env{GUIX_LOCPATH} environment
  1446. variable:
  1447. @example
  1448. $ guix install glibc-locales
  1449. $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
  1450. @end example
  1451. Note that the @code{glibc-locales} package contains data for all the
  1452. locales supported by the GNU@tie{}libc and weighs in at around
  1453. 917@tie{}MiB@. Alternatively, the @code{glibc-utf8-locales} is smaller but
  1454. limited to a few UTF-8 locales.
  1455. The @env{GUIX_LOCPATH} variable plays a role similar to @env{LOCPATH}
  1456. (@pxref{Locale Names, @env{LOCPATH},, libc, The GNU C Library Reference
  1457. Manual}). There are two important differences though:
  1458. @enumerate
  1459. @item
  1460. @env{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
  1461. provided by foreign distros. Thus, using @env{GUIX_LOCPATH} allows you
  1462. to make sure the programs of the foreign distro will not end up loading
  1463. incompatible locale data.
  1464. @item
  1465. libc suffixes each entry of @env{GUIX_LOCPATH} with @code{/X.Y}, where
  1466. @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
  1467. should your Guix profile contain a mixture of programs linked against
  1468. different libc version, each libc version will only try to load locale
  1469. data in the right format.
  1470. @end enumerate
  1471. This is important because the locale data format used by different libc
  1472. versions may be incompatible.
  1473. @subsection Name Service Switch
  1474. @cindex name service switch, glibc
  1475. @cindex NSS (name service switch), glibc
  1476. @cindex nscd (name service caching daemon)
  1477. @cindex name service caching daemon (nscd)
  1478. When using Guix on a foreign distro, we @emph{strongly recommend} that
  1479. the system run the GNU C library's @dfn{name service cache daemon},
  1480. @command{nscd}, which should be listening on the
  1481. @file{/var/run/nscd/socket} socket. Failing to do that, applications
  1482. installed with Guix may fail to look up host names or user accounts, or
  1483. may even crash. The next paragraphs explain why.
  1484. @cindex @file{nsswitch.conf}
  1485. The GNU C library implements a @dfn{name service switch} (NSS), which is
  1486. an extensible mechanism for ``name lookups'' in general: host name
  1487. resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
  1488. The GNU C Library Reference Manual}).
  1489. @cindex Network information service (NIS)
  1490. @cindex NIS (Network information service)
  1491. Being extensible, the NSS supports @dfn{plugins}, which provide new name
  1492. lookup implementations: for example, the @code{nss-mdns} plugin allow
  1493. resolution of @code{.local} host names, the @code{nis} plugin allows
  1494. user account lookup using the Network information service (NIS), and so
  1495. on. These extra ``lookup services'' are configured system-wide in
  1496. @file{/etc/nsswitch.conf}, and all the programs running on the system
  1497. honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
  1498. Reference Manual}).
  1499. When they perform a name lookup---for instance by calling the
  1500. @code{getaddrinfo} function in C---applications first try to connect to
  1501. the nscd; on success, nscd performs name lookups on their behalf. If
  1502. the nscd is not running, then they perform the name lookup by
  1503. themselves, by loading the name lookup services into their own address
  1504. space and running it. These name lookup services---the
  1505. @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
  1506. the host system's C library, rather than from the C library the
  1507. application is linked against (the C library coming from Guix).
  1508. And this is where the problem is: if your application is linked against
  1509. Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
  1510. another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
  1511. likely crash or have its name lookups fail unexpectedly.
  1512. Running @command{nscd} on the system, among other advantages, eliminates
  1513. this binary incompatibility problem because those @code{libnss_*.so}
  1514. files are loaded in the @command{nscd} process, not in applications
  1515. themselves.
  1516. @subsection X11 Fonts
  1517. @cindex fonts
  1518. The majority of graphical applications use Fontconfig to locate and
  1519. load fonts and perform X11-client-side rendering. The @code{fontconfig}
  1520. package in Guix looks for fonts in @file{$HOME/.guix-profile}
  1521. by default. Thus, to allow graphical applications installed with Guix
  1522. to display fonts, you have to install fonts with Guix as well.
  1523. Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
  1524. @code{font-gnu-freefont}.
  1525. @cindex @code{fc-cache}
  1526. @cindex font cache
  1527. Once you have installed or removed fonts, or when you notice an
  1528. application that does not find fonts, you may need to install Fontconfig
  1529. and to force an update of its font cache by running:
  1530. @example
  1531. guix install fontconfig
  1532. fc-cache -rv
  1533. @end example
  1534. To display text written in Chinese languages, Japanese, or Korean in
  1535. graphical applications, consider installing
  1536. @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
  1537. has multiple outputs, one per language family (@pxref{Packages with
  1538. Multiple Outputs}). For instance, the following command installs fonts
  1539. for Chinese languages:
  1540. @example
  1541. guix install font-adobe-source-han-sans:cn
  1542. @end example
  1543. @cindex @code{xterm}
  1544. Older programs such as @command{xterm} do not use Fontconfig and instead
  1545. rely on server-side font rendering. Such programs require to specify a
  1546. full name of a font using XLFD (X Logical Font Description), like this:
  1547. @example
  1548. -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
  1549. @end example
  1550. To be able to use such full names for the TrueType fonts installed in
  1551. your Guix profile, you need to extend the font path of the X server:
  1552. @c Note: 'xset' does not accept symlinks so the trick below arranges to
  1553. @c get at the real directory. See <https://bugs.gnu.org/30655>.
  1554. @example
  1555. xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
  1556. @end example
  1557. @cindex @code{xlsfonts}
  1558. After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
  1559. to make sure your TrueType fonts are listed there.
  1560. @subsection X.509 Certificates
  1561. @cindex @code{nss-certs}
  1562. The @code{nss-certs} package provides X.509 certificates, which allow
  1563. programs to authenticate Web servers accessed over HTTPS.
  1564. When using Guix on a foreign distro, you can install this package and
  1565. define the relevant environment variables so that packages know where to
  1566. look for certificates. @xref{X.509 Certificates}, for detailed
  1567. information.
  1568. @subsection Emacs Packages
  1569. @cindex @code{emacs}
  1570. When you install Emacs packages with Guix, the Elisp files are placed
  1571. under the @file{share/emacs/site-lisp/} directory of the profile in
  1572. which they are installed. The Elisp libraries are made available to
  1573. Emacs through the @env{EMACSLOADPATH} environment variable, which is
  1574. set when installing Emacs itself.
  1575. Additionally, autoload definitions are automatically evaluated at the
  1576. initialization of Emacs, by the Guix-specific
  1577. @code{guix-emacs-autoload-packages} procedure. If, for some reason, you
  1578. want to avoid auto-loading the Emacs packages installed with Guix, you
  1579. can do so by running Emacs with the @option{--no-site-file} option
  1580. (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
  1581. @node Upgrading Guix
  1582. @section Upgrading Guix
  1583. @cindex Upgrading Guix, on a foreign distro
  1584. To upgrade Guix, run:
  1585. @example
  1586. guix pull
  1587. @end example
  1588. @xref{Invoking guix pull}, for more information.
  1589. @cindex upgrading Guix for the root user, on a foreign distro
  1590. @cindex upgrading the Guix daemon, on a foreign distro
  1591. @cindex @command{guix pull} for the root user, on a foreign distro
  1592. On a foreign distro, you can upgrade the build daemon by running:
  1593. @example
  1594. sudo -i guix pull
  1595. @end example
  1596. @noindent
  1597. followed by (assuming your distro uses the systemd service management
  1598. tool):
  1599. @example
  1600. systemctl restart guix-daemon.service
  1601. @end example
  1602. On Guix System, upgrading the daemon is achieved by reconfiguring the
  1603. system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
  1604. @c TODO What else?
  1605. @c *********************************************************************
  1606. @node System Installation
  1607. @chapter System Installation
  1608. @cindex installing Guix System
  1609. @cindex Guix System, installation
  1610. This section explains how to install Guix System
  1611. on a machine. Guix, as a package manager, can
  1612. also be installed on top of a running GNU/Linux system,
  1613. @pxref{Installation}.
  1614. @ifinfo
  1615. @quotation Note
  1616. @c This paragraph is for people reading this from tty2 of the
  1617. @c installation image.
  1618. You are reading this documentation with an Info reader. For details on
  1619. how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
  1620. link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
  1621. Info}. Hit @kbd{l} afterwards to come back here.
  1622. Alternatively, run @command{info info} in another tty to keep the manual
  1623. available.
  1624. @end quotation
  1625. @end ifinfo
  1626. @menu
  1627. * Limitations:: What you can expect.
  1628. * Hardware Considerations:: Supported hardware.
  1629. * USB Stick and DVD Installation:: Preparing the installation medium.
  1630. * Preparing for Installation:: Networking, partitioning, etc.
  1631. * Guided Graphical Installation:: Easy graphical installation.
  1632. * Manual Installation:: Manual installation for wizards.
  1633. * After System Installation:: When installation succeeded.
  1634. * Installing Guix in a VM:: Guix System playground.
  1635. * Building the Installation Image:: How this comes to be.
  1636. @end menu
  1637. @node Limitations
  1638. @section Limitations
  1639. We consider Guix System to be ready for a wide range of ``desktop'' and server
  1640. use cases. The reliability guarantees it provides---transactional upgrades
  1641. and rollbacks, reproducibility---make it a solid foundation.
  1642. Nevertheless, before you proceed with the installation, be aware of the
  1643. following noteworthy limitations applicable to version @value{VERSION}:
  1644. @itemize
  1645. @item
  1646. More and more system services are provided (@pxref{Services}), but some
  1647. may be missing.
  1648. @item
  1649. GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
  1650. as well as a number of X11 window managers. However, KDE is currently
  1651. missing.
  1652. @end itemize
  1653. More than a disclaimer, this is an invitation to report issues (and success
  1654. stories!), and to join us in improving it. @xref{Contributing}, for more
  1655. info.
  1656. @node Hardware Considerations
  1657. @section Hardware Considerations
  1658. @cindex hardware support on Guix System
  1659. GNU@tie{}Guix focuses on respecting the user's computing freedom. It
  1660. builds around the kernel Linux-libre, which means that only hardware for
  1661. which free software drivers and firmware exist is supported. Nowadays,
  1662. a wide range of off-the-shelf hardware is supported on
  1663. GNU/Linux-libre---from keyboards to graphics cards to scanners and
  1664. Ethernet controllers. Unfortunately, there are still areas where
  1665. hardware vendors deny users control over their own computing, and such
  1666. hardware is not supported on Guix System.
  1667. @cindex WiFi, hardware support
  1668. One of the main areas where free drivers or firmware are lacking is WiFi
  1669. devices. WiFi devices known to work include those using Atheros chips
  1670. (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
  1671. driver, and those using Broadcom/AirForce chips (BCM43xx with
  1672. Wireless-Core Revision 5), which corresponds to the @code{b43-open}
  1673. Linux-libre driver. Free firmware exists for both and is available
  1674. out-of-the-box on Guix System, as part of @code{%base-firmware}
  1675. (@pxref{operating-system Reference, @code{firmware}}).
  1676. @cindex RYF, Respects Your Freedom
  1677. The @uref{https://www.fsf.org/, Free Software Foundation} runs
  1678. @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
  1679. certification program for hardware products that respect your freedom
  1680. and your privacy and ensure that you have control over your device. We
  1681. encourage you to check the list of RYF-certified devices.
  1682. Another useful resource is the @uref{https://www.h-node.org/, H-Node}
  1683. web site. It contains a catalog of hardware devices with information
  1684. about their support in GNU/Linux.
  1685. @node USB Stick and DVD Installation
  1686. @section USB Stick and DVD Installation
  1687. An ISO-9660 installation image that can be written to a USB stick or
  1688. burnt to a DVD can be downloaded from
  1689. @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.xz},
  1690. where you can replace @code{x86_64-linux} with one of:
  1691. @table @code
  1692. @item x86_64-linux
  1693. for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
  1694. @item i686-linux
  1695. for a 32-bit GNU/Linux system on Intel-compatible CPUs.
  1696. @end table
  1697. @c start duplication of authentication part from ``Binary Installation''
  1698. Make sure to download the associated @file{.sig} file and to verify the
  1699. authenticity of the image against it, along these lines:
  1700. @example
  1701. $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.xz.sig
  1702. $ gpg --verify guix-system-install-@value{VERSION}.x86_64-linux.iso.xz.sig
  1703. @end example
  1704. If that command fails because you do not have the required public key,
  1705. then run this command to import it:
  1706. @example
  1707. $ wget @value{OPENPGP-SIGNING-KEY-URL} \
  1708. -qO - | gpg --import -
  1709. @end example
  1710. @noindent
  1711. and rerun the @code{gpg --verify} command.
  1712. Take note that a warning like ``This key is not certified with a trusted
  1713. signature!'' is normal.
  1714. @c end duplication
  1715. This image contains the tools necessary for an installation.
  1716. It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
  1717. @unnumberedsubsec Copying to a USB Stick
  1718. To copy the image to a USB stick, follow these steps:
  1719. @enumerate
  1720. @item
  1721. Decompress the image using the @command{xz} command:
  1722. @example
  1723. xz -d guix-system-install-@value{VERSION}.x86_64-linux.iso.xz
  1724. @end example
  1725. @item
  1726. Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
  1727. its device name. Assuming that the USB stick is known as @file{/dev/sdX},
  1728. copy the image with:
  1729. @example
  1730. dd if=guix-system-install-@value{VERSION}.x86_64-linux.iso of=/dev/sdX status=progress
  1731. sync
  1732. @end example
  1733. Access to @file{/dev/sdX} usually requires root privileges.
  1734. @end enumerate
  1735. @unnumberedsubsec Burning on a DVD
  1736. To copy the image to a DVD, follow these steps:
  1737. @enumerate
  1738. @item
  1739. Decompress the image using the @command{xz} command:
  1740. @example
  1741. xz -d guix-system-install-@value{VERSION}.x86_64-linux.iso.xz
  1742. @end example
  1743. @item
  1744. Insert a blank DVD into your machine, and determine
  1745. its device name. Assuming that the DVD drive is known as @file{/dev/srX},
  1746. copy the image with:
  1747. @example
  1748. growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.x86_64-linux.iso
  1749. @end example
  1750. Access to @file{/dev/srX} usually requires root privileges.
  1751. @end enumerate
  1752. @unnumberedsubsec Booting
  1753. Once this is done, you should be able to reboot the system and boot from
  1754. the USB stick or DVD@. The latter usually requires you to get in the
  1755. BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
  1756. In order to boot from Libreboot, switch to the command mode by pressing
  1757. the @kbd{c} key and type @command{search_grub usb}.
  1758. @xref{Installing Guix in a VM}, if, instead, you would like to install
  1759. Guix System in a virtual machine (VM).
  1760. @node Preparing for Installation
  1761. @section Preparing for Installation
  1762. Once you have booted, you can use the guided graphical installer, which makes
  1763. it easy to get started (@pxref{Guided Graphical Installation}). Alternatively,
  1764. if you are already familiar with GNU/Linux and if you want more control than
  1765. what the graphical installer provides, you can choose the ``manual''
  1766. installation process (@pxref{Manual Installation}).
  1767. The graphical installer is available on TTY1. You can obtain root shells on
  1768. TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
  1769. this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
  1770. is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
  1771. Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
  1772. which allows you to select text with the left mouse button and to paste it
  1773. with the middle button.
  1774. @quotation Note
  1775. Installation requires access to the Internet so that any missing
  1776. dependencies of your system configuration can be downloaded. See the
  1777. ``Networking'' section below.
  1778. @end quotation
  1779. @node Guided Graphical Installation
  1780. @section Guided Graphical Installation
  1781. The graphical installer is a text-based user interface. It will guide you,
  1782. with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
  1783. The first dialog boxes allow you to set up the system as you use it during the
  1784. installation: you can choose the language, keyboard layout, and set up
  1785. networking, which will be used during the installation. The image below shows
  1786. the networking dialog.
  1787. @image{images/installer-network,5in,, networking setup with the graphical installer}
  1788. Later steps allow you to partition your hard disk, as shown in the image
  1789. below, to choose whether or not to use encrypted file systems, to enter the
  1790. host name and root password, and to create an additional account, among other
  1791. things.
  1792. @image{images/installer-partitions,5in,, partitioning with the graphical installer}
  1793. Note that, at any time, the installer allows you to exit the current
  1794. installation step and resume at a previous step, as show in the image below.
  1795. @image{images/installer-resume,5in,, resuming the installation process}
  1796. Once you're done, the installer produces an operating system configuration and
  1797. displays it (@pxref{Using the Configuration System}). At that point you can
  1798. hit ``OK'' and installation will proceed. On success, you can reboot into the
  1799. new system and enjoy. @xref{After System Installation}, for what's next!
  1800. @node Manual Installation
  1801. @section Manual Installation
  1802. This section describes how you would ``manually'' install GNU@tie{}Guix System
  1803. on your machine. This option requires familiarity with GNU/Linux, with the
  1804. shell, and with common administration tools. If you think this is not for
  1805. you, consider using the guided graphical installer (@pxref{Guided Graphical
  1806. Installation}).
  1807. The installation system provides root shells on TTYs 3 to 6; press
  1808. @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
  1809. many common tools needed to install the system. But it is also a full-blown
  1810. Guix System, which means that you can install additional packages, should you
  1811. need it, using @command{guix package} (@pxref{Invoking guix package}).
  1812. @menu
  1813. * Keyboard Layout and Networking and Partitioning:: Initial setup.
  1814. * Proceeding with the Installation:: Installing.
  1815. @end menu
  1816. @node Keyboard Layout and Networking and Partitioning
  1817. @subsection Keyboard Layout, Networking, and Partitioning
  1818. Before you can install the system, you may want to adjust the keyboard layout,
  1819. set up networking, and partition your target hard disk. This section will
  1820. guide you through this.
  1821. @subsubsection Keyboard Layout
  1822. @cindex keyboard layout
  1823. The installation image uses the US qwerty keyboard layout. If you want
  1824. to change it, you can use the @command{loadkeys} command. For example,
  1825. the following command selects the Dvorak keyboard layout:
  1826. @example
  1827. loadkeys dvorak
  1828. @end example
  1829. See the files under @file{/run/current-system/profile/share/keymaps} for
  1830. a list of available keyboard layouts. Run @command{man loadkeys} for
  1831. more information.
  1832. @subsubsection Networking
  1833. Run the following command to see what your network interfaces are called:
  1834. @example
  1835. ifconfig -a
  1836. @end example
  1837. @noindent
  1838. @dots{} or, using the GNU/Linux-specific @command{ip} command:
  1839. @example
  1840. ip address
  1841. @end example
  1842. @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
  1843. Wired interfaces have a name starting with @samp{e}; for example, the
  1844. interface corresponding to the first on-board Ethernet controller is
  1845. called @samp{eno1}. Wireless interfaces have a name starting with
  1846. @samp{w}, like @samp{w1p2s0}.
  1847. @table @asis
  1848. @item Wired connection
  1849. To configure a wired network run the following command, substituting
  1850. @var{interface} with the name of the wired interface you want to use.
  1851. @example
  1852. ifconfig @var{interface} up
  1853. @end example
  1854. @noindent
  1855. @dots{} or, using the GNU/Linux-specific @command{ip} command:
  1856. @example
  1857. ip link set @var{interface} up
  1858. @end example
  1859. @item Wireless connection
  1860. @cindex wireless
  1861. @cindex WiFi
  1862. To configure wireless networking, you can create a configuration file
  1863. for the @command{wpa_supplicant} configuration tool (its location is not
  1864. important) using one of the available text editors such as
  1865. @command{nano}:
  1866. @example
  1867. nano wpa_supplicant.conf
  1868. @end example
  1869. As an example, the following stanza can go to this file and will work
  1870. for many wireless networks, provided you give the actual SSID and
  1871. passphrase for the network you are connecting to:
  1872. @example
  1873. network=@{
  1874. ssid="@var{my-ssid}"
  1875. key_mgmt=WPA-PSK
  1876. psk="the network's secret passphrase"
  1877. @}
  1878. @end example
  1879. Start the wireless service and run it in the background with the
  1880. following command (substitute @var{interface} with the name of the
  1881. network interface you want to use):
  1882. @example
  1883. wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
  1884. @end example
  1885. Run @command{man wpa_supplicant} for more information.
  1886. @end table
  1887. @cindex DHCP
  1888. At this point, you need to acquire an IP address. On a network where IP
  1889. addresses are automatically assigned @i{via} DHCP, you can run:
  1890. @example
  1891. dhclient -v @var{interface}
  1892. @end example
  1893. Try to ping a server to see if networking is up and running:
  1894. @example
  1895. ping -c 3 gnu.org
  1896. @end example
  1897. Setting up network access is almost always a requirement because the
  1898. image does not contain all the software and tools that may be needed.
  1899. @cindex proxy, during system installation
  1900. If you need HTTP and HTTPS access to go through a proxy, run the
  1901. following command:
  1902. @example
  1903. herd set-http-proxy guix-daemon @var{URL}
  1904. @end example
  1905. @noindent
  1906. where @var{URL} is the proxy URL, for example
  1907. @code{http://example.org:8118}.
  1908. @cindex installing over SSH
  1909. If you want to, you can continue the installation remotely by starting
  1910. an SSH server:
  1911. @example
  1912. herd start ssh-daemon
  1913. @end example
  1914. Make sure to either set a password with @command{passwd}, or configure
  1915. OpenSSH public key authentication before logging in.
  1916. @subsubsection Disk Partitioning
  1917. Unless this has already been done, the next step is to partition, and
  1918. then format the target partition(s).
  1919. The installation image includes several partitioning tools, including
  1920. Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
  1921. @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
  1922. the partition layout you want:
  1923. @example
  1924. cfdisk
  1925. @end example
  1926. If your disk uses the GUID Partition Table (GPT) format and you plan to
  1927. install BIOS-based GRUB (which is the default), make sure a BIOS Boot
  1928. Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
  1929. manual}).
  1930. @cindex EFI, installation
  1931. @cindex UEFI, installation
  1932. @cindex ESP, EFI system partition
  1933. If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
  1934. (ESP) is required. This partition can be mounted at @file{/boot/efi} for
  1935. instance and must have the @code{esp} flag set. E.g., for @command{parted}:
  1936. @example
  1937. parted /dev/sda set 1 esp on
  1938. @end example
  1939. @quotation Note
  1940. @vindex grub-bootloader
  1941. @vindex grub-efi-bootloader
  1942. Unsure whether to use EFI- or BIOS-based GRUB? If the directory
  1943. @file{/sys/firmware/efi} exists in the installation image, then you should
  1944. probably perform an EFI installation, using @code{grub-efi-bootloader}.
  1945. Otherwise you should use the BIOS-based GRUB, known as
  1946. @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
  1947. bootloaders.
  1948. @end quotation
  1949. Once you are done partitioning the target hard disk drive, you have to
  1950. create a file system on the relevant partition(s)@footnote{Currently
  1951. Guix System only supports ext4, btrfs, JFS, and F2FS file systems. In
  1952. particular, code that reads file system UUIDs and labels only works for these
  1953. file system types.}. For the ESP, if you have one and assuming it is
  1954. @file{/dev/sda1}, run:
  1955. @example
  1956. mkfs.fat -F32 /dev/sda1
  1957. @end example
  1958. For the root file system, ext4 is the most widely used format. Other
  1959. file systems, such as Btrfs, support compression, which is reported to
  1960. nicely complement file deduplication that the daemon performs
  1961. independently of the file system (@pxref{Invoking guix-daemon,
  1962. deduplication}).
  1963. Preferably, assign file systems a label so that you can easily and
  1964. reliably refer to them in @code{file-system} declarations (@pxref{File
  1965. Systems}). This is typically done using the @code{-L} option of
  1966. @command{mkfs.ext4} and related commands. So, assuming the target root
  1967. partition lives at @file{/dev/sda2}, a file system with the label
  1968. @code{my-root} can be created with:
  1969. @example
  1970. mkfs.ext4 -L my-root /dev/sda2
  1971. @end example
  1972. @cindex encrypted disk
  1973. If you are instead planning to encrypt the root partition, you can use
  1974. the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
  1975. @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
  1976. @code{man cryptsetup}} for more information). Assuming you want to
  1977. store the root partition on @file{/dev/sda2}, the command sequence would
  1978. be along these lines:
  1979. @example
  1980. cryptsetup luksFormat /dev/sda2
  1981. cryptsetup open --type luks /dev/sda2 my-partition
  1982. mkfs.ext4 -L my-root /dev/mapper/my-partition
  1983. @end example
  1984. Once that is done, mount the target file system under @file{/mnt}
  1985. with a command like (again, assuming @code{my-root} is the label of the
  1986. root file system):
  1987. @example
  1988. mount LABEL=my-root /mnt
  1989. @end example
  1990. Also mount any other file systems you would like to use on the target
  1991. system relative to this path. If you have opted for @file{/boot/efi} as an
  1992. EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
  1993. found by @code{guix system init} afterwards.
  1994. Finally, if you plan to use one or more swap partitions (@pxref{Memory
  1995. Concepts, swap space,, libc, The GNU C Library Reference Manual}), make
  1996. sure to initialize them with @command{mkswap}. Assuming you have one
  1997. swap partition on @file{/dev/sda3}, you would run:
  1998. @example
  1999. mkswap /dev/sda3
  2000. swapon /dev/sda3
  2001. @end example
  2002. Alternatively, you may use a swap file. For example, assuming that in
  2003. the new system you want to use the file @file{/swapfile} as a swap file,
  2004. you would run@footnote{This example will work for many types of file
  2005. systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
  2006. btrfs), the required steps may be different. For details, see the
  2007. manual pages for @command{mkswap} and @command{swapon}.}:
  2008. @example
  2009. # This is 10 GiB of swap space. Adjust "count" to change the size.
  2010. dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
  2011. # For security, make the file readable and writable only by root.
  2012. chmod 600 /mnt/swapfile
  2013. mkswap /mnt/swapfile
  2014. swapon /mnt/swapfile
  2015. @end example
  2016. Note that if you have encrypted the root partition and created a swap
  2017. file in its file system as described above, then the encryption also
  2018. protects the swap file, just like any other file in that file system.
  2019. @node Proceeding with the Installation
  2020. @subsection Proceeding with the Installation
  2021. With the target partitions ready and the target root mounted on
  2022. @file{/mnt}, we're ready to go. First, run:
  2023. @example
  2024. herd start cow-store /mnt
  2025. @end example
  2026. This makes @file{/gnu/store} copy-on-write, such that packages added to it
  2027. during the installation phase are written to the target disk on @file{/mnt}
  2028. rather than kept in memory. This is necessary because the first phase of
  2029. the @command{guix system init} command (see below) entails downloads or
  2030. builds to @file{/gnu/store} which, initially, is an in-memory file system.
  2031. Next, you have to edit a file and
  2032. provide the declaration of the operating system to be installed. To
  2033. that end, the installation system comes with three text editors. We
  2034. recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
  2035. supports syntax highlighting and parentheses matching; other editors
  2036. include GNU Zile (an Emacs clone), and
  2037. nvi (a clone of the original BSD @command{vi} editor).
  2038. We strongly recommend storing that file on the target root file system, say,
  2039. as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
  2040. configuration file once you have rebooted into the newly-installed system.
  2041. @xref{Using the Configuration System}, for an overview of the
  2042. configuration file. The example configurations discussed in that
  2043. section are available under @file{/etc/configuration} in the
  2044. installation image. Thus, to get started with a system configuration
  2045. providing a graphical display server (a ``desktop'' system), you can run
  2046. something along these lines:
  2047. @example
  2048. # mkdir /mnt/etc
  2049. # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
  2050. # nano /mnt/etc/config.scm
  2051. @end example
  2052. You should pay attention to what your configuration file contains, and
  2053. in particular:
  2054. @itemize
  2055. @item
  2056. Make sure the @code{bootloader-configuration} form refers to the target
  2057. you want to install GRUB on. It should mention @code{grub-bootloader} if
  2058. you are installing GRUB in the legacy way, or @code{grub-efi-bootloader}
  2059. for newer UEFI systems. For legacy systems, the @code{target} field
  2060. names a device, like @code{/dev/sda}; for UEFI systems it names a path
  2061. to a mounted EFI partition, like @code{/boot/efi}; do make sure the path is
  2062. currently mounted and a @code{file-system} entry is specified in your
  2063. configuration.
  2064. @item
  2065. Be sure that your file system labels match the value of their respective
  2066. @code{device} fields in your @code{file-system} configuration, assuming
  2067. your @code{file-system} configuration uses the @code{file-system-label}
  2068. procedure in its @code{device} field.
  2069. @item
  2070. If there are encrypted or RAID partitions, make sure to add a
  2071. @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
  2072. @end itemize
  2073. Once you are done preparing the configuration file, the new system must
  2074. be initialized (remember that the target root file system is mounted
  2075. under @file{/mnt}):
  2076. @example
  2077. guix system init /mnt/etc/config.scm /mnt
  2078. @end example
  2079. @noindent
  2080. This copies all the necessary files and installs GRUB on
  2081. @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
  2082. more information, @pxref{Invoking guix system}. This command may trigger
  2083. downloads or builds of missing packages, which can take some time.
  2084. Once that command has completed---and hopefully succeeded!---you can run
  2085. @command{reboot} and boot into the new system. The @code{root} password
  2086. in the new system is initially empty; other users' passwords need to be
  2087. initialized by running the @command{passwd} command as @code{root},
  2088. unless your configuration specifies otherwise
  2089. (@pxref{user-account-password, user account passwords}).
  2090. @xref{After System Installation}, for what's next!
  2091. @node After System Installation
  2092. @section After System Installation
  2093. Success, you've now booted into Guix System! From then on, you can update the
  2094. system whenever you want by running, say:
  2095. @example
  2096. guix pull
  2097. sudo guix system reconfigure /etc/config.scm
  2098. @end example
  2099. @noindent
  2100. This builds a new system generation with the latest packages and services
  2101. (@pxref{Invoking guix system}). We recommend doing that regularly so that
  2102. your system includes the latest security updates (@pxref{Security Updates}).
  2103. @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
  2104. @quotation Note
  2105. @cindex sudo vs. @command{guix pull}
  2106. Note that @command{sudo guix} runs your user's @command{guix} command and
  2107. @emph{not} root's, because @command{sudo} leaves @env{PATH} unchanged. To
  2108. explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
  2109. The difference matters here, because @command{guix pull} updates
  2110. the @command{guix} command and package definitions only for the user it is run
  2111. as. This means that if you choose to use @command{guix system reconfigure} in
  2112. root's login shell, you'll need to @command{guix pull} separately.
  2113. @end quotation
  2114. Now, @pxref{Getting Started}, and
  2115. join us on @code{#guix} on the Freenode IRC network or on
  2116. @email{guix-devel@@gnu.org} to share your experience!
  2117. @node Installing Guix in a VM
  2118. @section Installing Guix in a Virtual Machine
  2119. @cindex virtual machine, Guix System installation
  2120. @cindex virtual private server (VPS)
  2121. @cindex VPS (virtual private server)
  2122. If you'd like to install Guix System in a virtual machine (VM) or on a
  2123. virtual private server (VPS) rather than on your beloved machine, this
  2124. section is for you.
  2125. To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
  2126. disk image, follow these steps:
  2127. @enumerate
  2128. @item
  2129. First, retrieve and decompress the Guix system installation image as
  2130. described previously (@pxref{USB Stick and DVD Installation}).
  2131. @item
  2132. Create a disk image that will hold the installed system. To make a
  2133. qcow2-formatted disk image, use the @command{qemu-img} command:
  2134. @example
  2135. qemu-img create -f qcow2 guix-system.img 50G
  2136. @end example
  2137. The resulting file will be much smaller than 50 GB (typically less than
  2138. 1 MB), but it will grow as the virtualized storage device is filled up.
  2139. @item
  2140. Boot the USB installation image in an VM:
  2141. @example
  2142. qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
  2143. -nic user,model=virtio-net-pci -boot menu=on,order=d \
  2144. -drive file=guix-system.img \
  2145. -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
  2146. @end example
  2147. @code{-enable-kvm} is optional, but significantly improves performance,
  2148. @pxref{Running Guix in a VM}.
  2149. @item
  2150. You're now root in the VM, proceed with the installation process.
  2151. @xref{Preparing for Installation}, and follow the instructions.
  2152. @end enumerate
  2153. Once installation is complete, you can boot the system that's on your
  2154. @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
  2155. that.
  2156. @node Building the Installation Image
  2157. @section Building the Installation Image
  2158. @cindex installation image
  2159. The installation image described above was built using the @command{guix
  2160. system} command, specifically:
  2161. @example
  2162. guix system image -t iso9660 gnu/system/install.scm
  2163. @end example
  2164. Have a look at @file{gnu/system/install.scm} in the source tree,
  2165. and see also @ref{Invoking guix system} for more information
  2166. about the installation image.
  2167. @section Building the Installation Image for ARM Boards
  2168. Many ARM boards require a specific variant of the
  2169. @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
  2170. If you build a disk image and the bootloader is not available otherwise
  2171. (on another boot drive etc), it's advisable to build an image that
  2172. includes the bootloader, specifically:
  2173. @example
  2174. guix system image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
  2175. @end example
  2176. @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
  2177. board, a list of possible boards will be printed.
  2178. @c *********************************************************************
  2179. @node Getting Started
  2180. @chapter Getting Started
  2181. Presumably, you've reached this section because either you have
  2182. installed Guix on top of another distribution (@pxref{Installation}), or
  2183. you've installed the standalone Guix System (@pxref{System
  2184. Installation}). It's time for you to get started using Guix and this
  2185. section aims to help you do that and give you a feel of what it's like.
  2186. Guix is about installing software, so probably the first thing you'll
  2187. want to do is to actually look for software. Let's say you're looking
  2188. for a text editor, you can run:
  2189. @example
  2190. guix search text editor
  2191. @end example
  2192. This command shows you a number of matching @dfn{packages}, each time
  2193. showing the package's name, version, a description, and additional info.
  2194. Once you've found out the one you want to use, let's say Emacs (ah ha!),
  2195. you can go ahead and install it (run this command as a regular user,
  2196. @emph{no need for root privileges}!):
  2197. @example
  2198. guix install emacs
  2199. @end example
  2200. @cindex profile
  2201. You've installed your first package, congrats! The package is now
  2202. visible in your default @dfn{profile}, @file{$HOME/.guix-profile}---a
  2203. profile is a directory containing installed packages.
  2204. In the process, you've
  2205. probably noticed that Guix downloaded pre-built binaries; or, if you
  2206. explicitly chose to @emph{not} use pre-built binaries, then probably
  2207. Guix is still building software (@pxref{Substitutes}, for more info).
  2208. Unless you're using Guix System, the @command{guix install} command must
  2209. have printed this hint:
  2210. @example
  2211. hint: Consider setting the necessary environment variables by running:
  2212. GUIX_PROFILE="$HOME/.guix-profile"
  2213. . "$GUIX_PROFILE/etc/profile"
  2214. Alternately, see `guix package --search-paths -p "$HOME/.guix-profile"'.
  2215. @end example
  2216. Indeed, you must now tell your shell where @command{emacs} and other
  2217. programs installed with Guix are to be found. Pasting the two lines
  2218. above will do just that: it will add
  2219. @code{$HOME/.guix-profile/bin}---which is where the installed package
  2220. is---to the @code{PATH} environment variable. You can paste these two
  2221. lines in your shell so they take effect right away, but more importantly
  2222. you should add them to @file{~/.bash_profile} (or equivalent file if you
  2223. do not use Bash) so that environment variables are set next time you
  2224. spawn a shell. You only need to do this once and other search paths
  2225. environment variables will be taken care of similarly---e.g., if you
  2226. eventually install @code{python} and Python libraries, @code{PYTHONPATH}
  2227. will be defined.
  2228. You can go on installing packages at your will. To list installed
  2229. packages, run:
  2230. @example
  2231. guix package --list-installed
  2232. @end example
  2233. To remove a package, you would unsurprisingly run @command{guix remove}.
  2234. A distinguishing feature is the ability to @dfn{roll back} any operation
  2235. you made---installation, removal, upgrade---by simply typing:
  2236. @example
  2237. guix package --roll-back
  2238. @end example
  2239. This is because each operation is in fact a @dfn{transaction} that
  2240. creates a new @dfn{generation}. These generations and the difference
  2241. between them can be displayed by running:
  2242. @example
  2243. guix package --list-generations
  2244. @end example
  2245. Now you know the basics of package management!
  2246. @quotation Going further
  2247. @xref{Package Management}, for more about package management. You may
  2248. like @dfn{declarative} package management with @command{guix package
  2249. --manifest}, managing separate @dfn{profiles} with @option{--profile},
  2250. deleting old generations, collecting garbage, and other nifty features
  2251. that will come in handy as you become more familiar with Guix. If you
  2252. are a developer, @pxref{Development} for additional tools. And if
  2253. you're curious, @pxref{Features}, to peek under the hood.
  2254. @end quotation
  2255. Once you've installed a set of packages, you will want to periodically
  2256. @emph{upgrade} them to the latest and greatest version. To do that, you
  2257. will first pull the latest revision of Guix and its package collection:
  2258. @example
  2259. guix pull
  2260. @end example
  2261. The end result is a new @command{guix} command, under
  2262. @file{~/.config/guix/current/bin}. Unless you're on Guix System, the
  2263. first time you run @command{guix pull}, be sure to follow the hint that
  2264. the command prints and, similar to what we saw above, paste these two
  2265. lines in your terminal and @file{.bash_profile}:
  2266. @example
  2267. GUIX_PROFILE="$HOME/.config/guix/current"
  2268. . "$GUIX_PROFILE/etc/profile"
  2269. @end example
  2270. @noindent
  2271. You must also instruct your shell to point to this new @command{guix}:
  2272. @example
  2273. hash guix
  2274. @end example
  2275. At this point, you're running a brand new Guix. You can thus go ahead
  2276. and actually upgrade all the packages you previously installed:
  2277. @example
  2278. guix upgrade
  2279. @end example
  2280. As you run this command, you will see that binaries are downloaded (or
  2281. perhaps some packages are built), and eventually you end up with the
  2282. upgraded packages. Should one of these upgraded packages not be to your
  2283. liking, remember you can always roll back!
  2284. You can display the exact revision of Guix you're currently using by
  2285. running:
  2286. @example
  2287. guix describe
  2288. @end example
  2289. The information it displays is @emph{all it takes to reproduce the exact
  2290. same Guix}, be it at a different point in time or on a different
  2291. machine.
  2292. @quotation Going further
  2293. @xref{Invoking guix pull}, for more information. @xref{Channels}, on
  2294. how to specify additional @dfn{channels} to pull packages from, how to
  2295. replicate Guix, and more. You may also find @command{time-machine}
  2296. handy (@pxref{Invoking guix time-machine}).
  2297. @end quotation
  2298. If you installed Guix System, one of the first things you'll want to do
  2299. is to upgrade your system. Once you've run @command{guix pull} to get
  2300. the latest Guix, you can upgrade the system like this:
  2301. @example
  2302. sudo guix system reconfigure /etc/config.scm
  2303. @end example
  2304. Upon completion, the system runs the latest versions of its software
  2305. packages. When you eventually reboot, you'll notice a sub-menu in the
  2306. bootloader that reads ``Old system generations'': it's what allows you
  2307. to boot @emph{an older generation of your system}, should the latest
  2308. generation be ``broken'' or otherwise unsatisfying. Just like for
  2309. packages, you can always @emph{roll back} to a previous generation
  2310. @emph{of the whole system}:
  2311. @example
  2312. sudo guix system roll-back
  2313. @end example
  2314. There are many things you'll probably want to tweak on your system:
  2315. adding new user accounts, adding new system services, fiddling with the
  2316. configuration of those services, etc. The system configuration is
  2317. @emph{entirely} described in the @file{/etc/config.scm} file.
  2318. @xref{Using the Configuration System}, to learn how to change it.
  2319. Now you know enough to get started!
  2320. @quotation Resources
  2321. The rest of this manual provides a reference for all things Guix. Here
  2322. are some additional resources you may find useful:
  2323. @itemize
  2324. @item
  2325. @xref{Top,,, guix-cookbook, The GNU Guix Cookbook}, for a list of
  2326. ``how-to'' style of recipes for a variety of applications.
  2327. @item
  2328. The @uref{https://guix.gnu.org/guix-refcard.pdf, GNU Guix Reference
  2329. Card} lists in two pages most of the commands and options you'll ever
  2330. need.
  2331. @item
  2332. The web site contains @uref{https://guix.gnu.org/en/videos/,
  2333. instructional videos} covering topics such as everyday use of Guix, how
  2334. to get help, and how to become a contributor.
  2335. @item
  2336. @xref{Documentation}, to learn how to access documentation on your
  2337. computer.
  2338. @end itemize
  2339. We hope you will enjoy Guix as much as the community enjoys building it!
  2340. @end quotation
  2341. @c *********************************************************************
  2342. @node Package Management
  2343. @chapter Package Management
  2344. @cindex packages
  2345. The purpose of GNU Guix is to allow users to easily install, upgrade, and
  2346. remove software packages, without having to know about their build
  2347. procedures or dependencies. Guix also goes beyond this obvious set of
  2348. features.
  2349. This chapter describes the main features of Guix, as well as the
  2350. package management tools it provides. Along with the command-line
  2351. interface described below (@pxref{Invoking guix package, @code{guix
  2352. package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
  2353. emacs-guix, The Emacs-Guix Reference Manual}), after installing
  2354. @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
  2355. with it):
  2356. @example
  2357. guix install emacs-guix
  2358. @end example
  2359. @menu
  2360. * Features:: How Guix will make your life brighter.
  2361. * Invoking guix package:: Package installation, removal, etc.
  2362. * Substitutes:: Downloading pre-built binaries.
  2363. * Packages with Multiple Outputs:: Single source package, multiple outputs.
  2364. * Invoking guix gc:: Running the garbage collector.
  2365. * Invoking guix pull:: Fetching the latest Guix and distribution.
  2366. * Invoking guix time-machine:: Running an older revision of Guix.
  2367. * Inferiors:: Interacting with another revision of Guix.
  2368. * Invoking guix describe:: Display information about your Guix revision.
  2369. * Invoking guix archive:: Exporting and importing store files.
  2370. @end menu
  2371. @node Features
  2372. @section Features
  2373. Here we assume you've already made your first steps with Guix
  2374. (@pxref{Getting Started}) and would like to get an overview about what's
  2375. going on under the hood.
  2376. When using Guix, each package ends up in the @dfn{package store}, in its
  2377. own directory---something that resembles
  2378. @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
  2379. Instead of referring to these directories, users have their own
  2380. @dfn{profile}, which points to the packages that they actually want to
  2381. use. These profiles are stored within each user's home directory, at
  2382. @code{$HOME/.guix-profile}.
  2383. For example, @code{alice} installs GCC 4.7.2. As a result,
  2384. @file{/home/alice/.guix-profile/bin/gcc} points to
  2385. @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
  2386. @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
  2387. simply continues to point to
  2388. @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
  2389. coexist on the same system without any interference.
  2390. The @command{guix package} command is the central tool to manage
  2391. packages (@pxref{Invoking guix package}). It operates on the per-user
  2392. profiles, and can be used @emph{with normal user privileges}.
  2393. @cindex transactions
  2394. The command provides the obvious install, remove, and upgrade
  2395. operations. Each invocation is actually a @emph{transaction}: either
  2396. the specified operation succeeds, or nothing happens. Thus, if the
  2397. @command{guix package} process is terminated during the transaction,
  2398. or if a power outage occurs during the transaction, then the user's
  2399. profile remains in its previous state, and remains usable.
  2400. In addition, any package transaction may be @emph{rolled back}. So, if,
  2401. for example, an upgrade installs a new version of a package that turns
  2402. out to have a serious bug, users may roll back to the previous instance
  2403. of their profile, which was known to work well. Similarly, the global
  2404. system configuration on Guix is subject to
  2405. transactional upgrades and roll-back
  2406. (@pxref{Using the Configuration System}).
  2407. All packages in the package store may be @emph{garbage-collected}.
  2408. Guix can determine which packages are still referenced by user
  2409. profiles, and remove those that are provably no longer referenced
  2410. (@pxref{Invoking guix gc}). Users may also explicitly remove old
  2411. generations of their profile so that the packages they refer to can be
  2412. collected.
  2413. @cindex reproducibility
  2414. @cindex reproducible builds
  2415. Guix takes a @dfn{purely functional} approach to package
  2416. management, as described in the introduction (@pxref{Introduction}).
  2417. Each @file{/gnu/store} package directory name contains a hash of all the
  2418. inputs that were used to build that package---compiler, libraries, build
  2419. scripts, etc. This direct correspondence allows users to make sure a
  2420. given package installation matches the current state of their
  2421. distribution. It also helps maximize @dfn{build reproducibility}:
  2422. thanks to the isolated build environments that are used, a given build
  2423. is likely to yield bit-identical files when performed on different
  2424. machines (@pxref{Invoking guix-daemon, container}).
  2425. @cindex substitutes
  2426. This foundation allows Guix to support @dfn{transparent binary/source
  2427. deployment}. When a pre-built binary for a @file{/gnu/store} item is
  2428. available from an external source---a @dfn{substitute}, Guix just
  2429. downloads it and unpacks it;
  2430. otherwise, it builds the package from source, locally
  2431. (@pxref{Substitutes}). Because build results are usually bit-for-bit
  2432. reproducible, users do not have to trust servers that provide
  2433. substitutes: they can force a local build and @emph{challenge} providers
  2434. (@pxref{Invoking guix challenge}).
  2435. Control over the build environment is a feature that is also useful for
  2436. developers. The @command{guix environment} command allows developers of
  2437. a package to quickly set up the right development environment for their
  2438. package, without having to manually install the dependencies of the
  2439. package into their profile (@pxref{Invoking guix environment}).
  2440. @cindex replication, of software environments
  2441. @cindex provenance tracking, of software artifacts
  2442. All of Guix and its package definitions is version-controlled, and
  2443. @command{guix pull} allows you to ``travel in time'' on the history of Guix
  2444. itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
  2445. Guix instance on a different machine or at a later point in time, which in
  2446. turn allows you to @emph{replicate complete software environments}, while
  2447. retaining precise @dfn{provenance tracking} of the software.
  2448. @node Invoking guix package
  2449. @section Invoking @command{guix package}
  2450. @cindex installing packages
  2451. @cindex removing packages
  2452. @cindex package installation
  2453. @cindex package removal
  2454. @cindex profile
  2455. The @command{guix package} command is the tool that allows users to
  2456. install, upgrade, and remove packages, as well as rolling back to
  2457. previous configurations. These operations work on a user
  2458. @dfn{profile}---a directory of installed packages. Each user has a
  2459. default profile in @file{$HOME/.guix-profile}.
  2460. The command operates only on the user's own profile,
  2461. and works with normal user privileges (@pxref{Features}). Its syntax
  2462. is:
  2463. @example
  2464. guix package @var{options}
  2465. @end example
  2466. @cindex transactions
  2467. Primarily, @var{options} specifies the operations to be performed during
  2468. the transaction. Upon completion, a new profile is created, but
  2469. previous @dfn{generations} of the profile remain available, should the user
  2470. want to roll back.
  2471. For example, to remove @code{lua} and install @code{guile} and
  2472. @code{guile-cairo} in a single transaction:
  2473. @example
  2474. guix package -r lua -i guile guile-cairo
  2475. @end example
  2476. @cindex aliases, for @command{guix package}
  2477. For your convenience, we also provide the following aliases:
  2478. @itemize
  2479. @item
  2480. @command{guix search} is an alias for @command{guix package -s},
  2481. @item
  2482. @command{guix install} is an alias for @command{guix package -i},
  2483. @item
  2484. @command{guix remove} is an alias for @command{guix package -r},
  2485. @item
  2486. @command{guix upgrade} is an alias for @command{guix package -u},
  2487. @item
  2488. and @command{guix show} is an alias for @command{guix package --show=}.
  2489. @end itemize
  2490. These aliases are less expressive than @command{guix package} and provide
  2491. fewer options, so in some cases you'll probably want to use @command{guix
  2492. package} directly.
  2493. @command{guix package} also supports a @dfn{declarative approach}
  2494. whereby the user specifies the exact set of packages to be available and
  2495. passes it @i{via} the @option{--manifest} option
  2496. (@pxref{profile-manifest, @option{--manifest}}).
  2497. @cindex profile
  2498. For each user, a symlink to the user's default profile is automatically
  2499. created in @file{$HOME/.guix-profile}. This symlink always points to the
  2500. current generation of the user's default profile. Thus, users can add
  2501. @file{$HOME/.guix-profile/bin} to their @env{PATH} environment
  2502. variable, and so on.
  2503. @cindex search paths
  2504. If you are not using Guix System, consider adding the
  2505. following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
  2506. Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
  2507. shells get all the right environment variable definitions:
  2508. @example
  2509. GUIX_PROFILE="$HOME/.guix-profile" ; \
  2510. source "$GUIX_PROFILE/etc/profile"
  2511. @end example
  2512. In a multi-user setup, user profiles are stored in a place registered as
  2513. a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
  2514. to (@pxref{Invoking guix gc}). That directory is normally
  2515. @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
  2516. @var{localstatedir} is the value passed to @code{configure} as
  2517. @option{--localstatedir}, and @var{user} is the user name. The
  2518. @file{per-user} directory is created when @command{guix-daemon} is
  2519. started, and the @var{user} sub-directory is created by @command{guix
  2520. package}.
  2521. The @var{options} can be among the following:
  2522. @table @code
  2523. @item --install=@var{package} @dots{}
  2524. @itemx -i @var{package} @dots{}
  2525. Install the specified @var{package}s.
  2526. Each @var{package} may specify either a simple package name, such as
  2527. @code{guile}, or a package name followed by an at-sign and version number,
  2528. such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
  2529. case, the newest version prefixed by @code{1.8} is selected).
  2530. If no version number is specified, the
  2531. newest available version will be selected. In addition, @var{package}
  2532. may contain a colon, followed by the name of one of the outputs of the
  2533. package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
  2534. (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
  2535. name (and optionally version) are searched for among the GNU
  2536. distribution modules (@pxref{Package Modules}).
  2537. @cindex propagated inputs
  2538. Sometimes packages have @dfn{propagated inputs}: these are dependencies
  2539. that automatically get installed along with the required package
  2540. (@pxref{package-propagated-inputs, @code{propagated-inputs} in
  2541. @code{package} objects}, for information about propagated inputs in
  2542. package definitions).
  2543. @anchor{package-cmd-propagated-inputs}
  2544. An example is the GNU MPC library: its C header files refer to those of
  2545. the GNU MPFR library, which in turn refer to those of the GMP library.
  2546. Thus, when installing MPC, the MPFR and GMP libraries also get installed
  2547. in the profile; removing MPC also removes MPFR and GMP---unless they had
  2548. also been explicitly installed by the user.
  2549. Besides, packages sometimes rely on the definition of environment
  2550. variables for their search paths (see explanation of
  2551. @option{--search-paths} below). Any missing or possibly incorrect
  2552. environment variable definitions are reported here.
  2553. @item --install-from-expression=@var{exp}
  2554. @itemx -e @var{exp}
  2555. Install the package @var{exp} evaluates to.
  2556. @var{exp} must be a Scheme expression that evaluates to a
  2557. @code{<package>} object. This option is notably useful to disambiguate
  2558. between same-named variants of a package, with expressions such as
  2559. @code{(@@ (gnu packages base) guile-final)}.
  2560. Note that this option installs the first output of the specified
  2561. package, which may be insufficient when needing a specific output of a
  2562. multiple-output package.
  2563. @item --install-from-file=@var{file}
  2564. @itemx -f @var{file}
  2565. Install the package that the code within @var{file} evaluates to.
  2566. As an example, @var{file} might contain a definition like this
  2567. (@pxref{Defining Packages}):
  2568. @lisp
  2569. @include package-hello.scm
  2570. @end lisp
  2571. Developers may find it useful to include such a @file{guix.scm} file
  2572. in the root of their project source tree that can be used to test
  2573. development snapshots and create reproducible development environments
  2574. (@pxref{Invoking guix environment}).
  2575. The @var{file} may also contain a JSON representation of one or more
  2576. package definitions. Running @code{guix package -f} on
  2577. @file{hello.json} with the following contents would result in installing
  2578. the package @code{greeter} after building @code{myhello}:
  2579. @example
  2580. @verbatiminclude package-hello.json
  2581. @end example
  2582. @item --remove=@var{package} @dots{}
  2583. @itemx -r @var{package} @dots{}
  2584. Remove the specified @var{package}s.
  2585. As for @option{--install}, each @var{package} may specify a version number
  2586. and/or output name in addition to the package name. For instance,
  2587. @samp{-r glibc:debug} would remove the @code{debug} output of
  2588. @code{glibc}.
  2589. @item --upgrade[=@var{regexp} @dots{}]
  2590. @itemx -u [@var{regexp} @dots{}]
  2591. @cindex upgrading packages
  2592. Upgrade all the installed packages. If one or more @var{regexp}s are
  2593. specified, upgrade only installed packages whose name matches a
  2594. @var{regexp}. Also see the @option{--do-not-upgrade} option below.
  2595. Note that this upgrades package to the latest version of packages found
  2596. in the distribution currently installed. To update your distribution,
  2597. you should regularly run @command{guix pull} (@pxref{Invoking guix
  2598. pull}).
  2599. @cindex package transformations, upgrades
  2600. When upgrading, package transformations that were originally applied
  2601. when creating the profile are automatically re-applied (@pxref{Package
  2602. Transformation Options}). For example, assume you first installed Emacs
  2603. from the tip of its development branch with:
  2604. @example
  2605. guix install emacs-next --with-branch=emacs-next=master
  2606. @end example
  2607. Next time you run @command{guix upgrade}, Guix will again pull the tip
  2608. of the Emacs development branch and build @code{emacs-next} from that
  2609. checkout.
  2610. Note that transformation options such as @option{--with-branch} and
  2611. @option{--with-source} depend on external state; it is up to you to
  2612. ensure that they work as expected. You can also discard a
  2613. transformations that apply to a package by running:
  2614. @example
  2615. guix install @var{package}
  2616. @end example
  2617. @item --do-not-upgrade[=@var{regexp} @dots{}]
  2618. When used together with the @option{--upgrade} option, do @emph{not}
  2619. upgrade any packages whose name matches a @var{regexp}. For example, to
  2620. upgrade all packages in the current profile except those containing the
  2621. substring ``emacs'':
  2622. @example
  2623. $ guix package --upgrade . --do-not-upgrade emacs
  2624. @end example
  2625. @item @anchor{profile-manifest}--manifest=@var{file}
  2626. @itemx -m @var{file}
  2627. @cindex profile declaration
  2628. @cindex profile manifest
  2629. Create a new generation of the profile from the manifest object
  2630. returned by the Scheme code in @var{file}. This option can be repeated
  2631. several times, in which case the manifests are concatenated.
  2632. This allows you to @emph{declare} the profile's contents rather than
  2633. constructing it through a sequence of @option{--install} and similar
  2634. commands. The advantage is that @var{file} can be put under version
  2635. control, copied to different machines to reproduce the same profile, and
  2636. so on.
  2637. @c FIXME: Add reference to (guix profile) documentation when available.
  2638. @var{file} must return a @dfn{manifest} object, which is roughly a list
  2639. of packages:
  2640. @findex packages->manifest
  2641. @lisp
  2642. (use-package-modules guile emacs)
  2643. (packages->manifest
  2644. (list emacs
  2645. guile-2.0
  2646. ;; Use a specific package output.
  2647. (list guile-2.0 "debug")))
  2648. @end lisp
  2649. @findex specifications->manifest
  2650. In this example we have to know which modules define the @code{emacs}
  2651. and @code{guile-2.0} variables to provide the right
  2652. @code{use-package-modules} line, which can be cumbersome. We can
  2653. instead provide regular package specifications and let
  2654. @code{specifications->manifest} look up the corresponding package
  2655. objects, like this:
  2656. @lisp
  2657. (specifications->manifest
  2658. '("emacs" "guile@@2.2" "guile@@2.2:debug"))
  2659. @end lisp
  2660. @xref{export-manifest, @option{--export-manifest}}, to learn how to
  2661. obtain a manifest file from an existing profile.
  2662. @item --roll-back
  2663. @cindex rolling back
  2664. @cindex undoing transactions
  2665. @cindex transactions, undoing
  2666. Roll back to the previous @dfn{generation} of the profile---i.e., undo
  2667. the last transaction.
  2668. When combined with options such as @option{--install}, roll back occurs
  2669. before any other actions.
  2670. When rolling back from the first generation that actually contains
  2671. installed packages, the profile is made to point to the @dfn{zeroth
  2672. generation}, which contains no files apart from its own metadata.
  2673. After having rolled back, installing, removing, or upgrading packages
  2674. overwrites previous future generations. Thus, the history of the
  2675. generations in a profile is always linear.
  2676. @item --switch-generation=@var{pattern}
  2677. @itemx -S @var{pattern}
  2678. @cindex generations
  2679. Switch to a particular generation defined by @var{pattern}.
  2680. @var{pattern} may be either a generation number or a number prefixed
  2681. with ``+'' or ``-''. The latter means: move forward/backward by a
  2682. specified number of generations. For example, if you want to return to
  2683. the latest generation after @option{--roll-back}, use
  2684. @option{--switch-generation=+1}.
  2685. The difference between @option{--roll-back} and
  2686. @option{--switch-generation=-1} is that @option{--switch-generation} will
  2687. not make a zeroth generation, so if a specified generation does not
  2688. exist, the current generation will not be changed.
  2689. @item --search-paths[=@var{kind}]
  2690. @cindex search paths
  2691. Report environment variable definitions, in Bash syntax, that may be
  2692. needed in order to use the set of installed packages. These environment
  2693. variables are used to specify @dfn{search paths} for files used by some
  2694. of the installed packages.
  2695. For example, GCC needs the @env{CPATH} and @env{LIBRARY_PATH}
  2696. environment variables to be defined so it can look for headers and
  2697. libraries in the user's profile (@pxref{Environment Variables,,, gcc,
  2698. Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
  2699. library are installed in the profile, then @option{--search-paths} will
  2700. suggest setting these variables to @file{@var{profile}/include} and
  2701. @file{@var{profile}/lib}, respectively.
  2702. The typical use case is to define these environment variables in the
  2703. shell:
  2704. @example
  2705. $ eval `guix package --search-paths`
  2706. @end example
  2707. @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
  2708. meaning that the returned environment variable definitions will either
  2709. be exact settings, or prefixes or suffixes of the current value of these
  2710. variables. When omitted, @var{kind} defaults to @code{exact}.
  2711. This option can also be used to compute the @emph{combined} search paths
  2712. of several profiles. Consider this example:
  2713. @example
  2714. $ guix package -p foo -i guile
  2715. $ guix package -p bar -i guile-json
  2716. $ guix package -p foo -p bar --search-paths
  2717. @end example
  2718. The last command above reports about the @env{GUILE_LOAD_PATH}
  2719. variable, even though, taken individually, neither @file{foo} nor
  2720. @file{bar} would lead to that recommendation.
  2721. @cindex profile, choosing
  2722. @item --profile=@var{profile}
  2723. @itemx -p @var{profile}
  2724. Use @var{profile} instead of the user's default profile.
  2725. @var{profile} must be the name of a file that will be created upon
  2726. completion. Concretely, @var{profile} will be a mere symbolic link
  2727. (``symlink'') pointing to the actual profile where packages are
  2728. installed:
  2729. @example
  2730. $ guix install hello -p ~/code/my-profile
  2731. @dots{}
  2732. $ ~/code/my-profile/bin/hello
  2733. Hello, world!
  2734. @end example
  2735. All it takes to get rid of the profile is to remove this symlink and its
  2736. siblings that point to specific generations:
  2737. @example
  2738. $ rm ~/code/my-profile ~/code/my-profile-*-link
  2739. @end example
  2740. @item --list-profiles
  2741. List all the user's profiles:
  2742. @example
  2743. $ guix package --list-profiles
  2744. /home/charlie/.guix-profile
  2745. /home/charlie/code/my-profile
  2746. /home/charlie/code/devel-profile
  2747. /home/charlie/tmp/test
  2748. @end example
  2749. When running as root, list all the profiles of all the users.
  2750. @cindex collisions, in a profile
  2751. @cindex colliding packages in profiles
  2752. @cindex profile collisions
  2753. @item --allow-collisions
  2754. Allow colliding packages in the new profile. Use at your own risk!
  2755. By default, @command{guix package} reports as an error @dfn{collisions}
  2756. in the profile. Collisions happen when two or more different versions
  2757. or variants of a given package end up in the profile.
  2758. @item --bootstrap
  2759. Use the bootstrap Guile to build the profile. This option is only
  2760. useful to distribution developers.
  2761. @end table
  2762. In addition to these actions, @command{guix package} supports the
  2763. following options to query the current state of a profile, or the
  2764. availability of packages:
  2765. @table @option
  2766. @item --search=@var{regexp}
  2767. @itemx -s @var{regexp}
  2768. @anchor{guix-search}
  2769. @cindex searching for packages
  2770. List the available packages whose name, synopsis, or description matches
  2771. @var{regexp} (in a case-insensitive fashion), sorted by relevance.
  2772. Print all the metadata of matching packages in
  2773. @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
  2774. GNU recutils manual}).
  2775. This allows specific fields to be extracted using the @command{recsel}
  2776. command, for instance:
  2777. @example
  2778. $ guix package -s malloc | recsel -p name,version,relevance
  2779. name: jemalloc
  2780. version: 4.5.0
  2781. relevance: 6
  2782. name: glibc
  2783. version: 2.25
  2784. relevance: 1
  2785. name: libgc
  2786. version: 7.6.0
  2787. relevance: 1
  2788. @end example
  2789. Similarly, to show the name of all the packages available under the
  2790. terms of the GNU@tie{}LGPL version 3:
  2791. @example
  2792. $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
  2793. name: elfutils
  2794. name: gmp
  2795. @dots{}
  2796. @end example
  2797. It is also possible to refine search results using several @code{-s} flags to
  2798. @command{guix package}, or several arguments to @command{guix search}. For
  2799. example, the following command returns a list of board games (this time using
  2800. the @command{guix search} alias):
  2801. @example
  2802. $ guix search '\<board\>' game | recsel -p name
  2803. name: gnubg
  2804. @dots{}
  2805. @end example
  2806. If we were to omit @code{-s game}, we would also get software packages
  2807. that deal with printed circuit boards; removing the angle brackets
  2808. around @code{board} would further add packages that have to do with
  2809. keyboards.
  2810. And now for a more elaborate example. The following command searches
  2811. for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
  2812. libraries, and prints the name and synopsis of the matching packages:
  2813. @example
  2814. $ guix search crypto library | \
  2815. recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
  2816. @end example
  2817. @noindent
  2818. @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
  2819. information on @dfn{selection expressions} for @code{recsel -e}.
  2820. @item --show=@var{package}
  2821. Show details about @var{package}, taken from the list of available packages, in
  2822. @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
  2823. recutils manual}).
  2824. @example
  2825. $ guix package --show=python | recsel -p name,version
  2826. name: python
  2827. version: 2.7.6
  2828. name: python
  2829. version: 3.3.5
  2830. @end example
  2831. You may also specify the full name of a package to only get details about a
  2832. specific version of it (this time using the @command{guix show} alias):
  2833. @example
  2834. $ guix show python@@3.4 | recsel -p name,version
  2835. name: python
  2836. version: 3.4.3
  2837. @end example
  2838. @item --list-installed[=@var{regexp}]
  2839. @itemx -I [@var{regexp}]
  2840. List the currently installed packages in the specified profile, with the
  2841. most recently installed packages shown last. When @var{regexp} is
  2842. specified, list only installed packages whose name matches @var{regexp}.
  2843. For each installed package, print the following items, separated by
  2844. tabs: the package name, its version string, the part of the package that
  2845. is installed (for instance, @code{out} for the default output,
  2846. @code{include} for its headers, etc.), and the path of this package in
  2847. the store.
  2848. @item --list-available[=@var{regexp}]
  2849. @itemx -A [@var{regexp}]
  2850. List packages currently available in the distribution for this system
  2851. (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
  2852. available packages whose name matches @var{regexp}.
  2853. For each package, print the following items separated by tabs: its name,
  2854. its version string, the parts of the package (@pxref{Packages with
  2855. Multiple Outputs}), and the source location of its definition.
  2856. @item --list-generations[=@var{pattern}]
  2857. @itemx -l [@var{pattern}]
  2858. @cindex generations
  2859. Return a list of generations along with their creation dates; for each
  2860. generation, show the installed packages, with the most recently
  2861. installed packages shown last. Note that the zeroth generation is never
  2862. shown.
  2863. For each installed package, print the following items, separated by
  2864. tabs: the name of a package, its version string, the part of the package
  2865. that is installed (@pxref{Packages with Multiple Outputs}), and the
  2866. location of this package in the store.
  2867. When @var{pattern} is used, the command returns only matching
  2868. generations. Valid patterns include:
  2869. @itemize
  2870. @item @emph{Integers and comma-separated integers}. Both patterns denote
  2871. generation numbers. For instance, @option{--list-generations=1} returns
  2872. the first one.
  2873. And @option{--list-generations=1,8,2} outputs three generations in the
  2874. specified order. Neither spaces nor trailing commas are allowed.
  2875. @item @emph{Ranges}. @option{--list-generations=2..9} prints the
  2876. specified generations and everything in between. Note that the start of
  2877. a range must be smaller than its end.
  2878. It is also possible to omit the endpoint. For example,
  2879. @option{--list-generations=2..}, returns all generations starting from the
  2880. second one.
  2881. @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
  2882. or months by passing an integer along with the first letter of the
  2883. duration. For example, @option{--list-generations=20d} lists generations
  2884. that are up to 20 days old.
  2885. @end itemize
  2886. @item --delete-generations[=@var{pattern}]
  2887. @itemx -d [@var{pattern}]
  2888. When @var{pattern} is omitted, delete all generations except the current
  2889. one.
  2890. This command accepts the same patterns as @option{--list-generations}.
  2891. When @var{pattern} is specified, delete the matching generations. When
  2892. @var{pattern} specifies a duration, generations @emph{older} than the
  2893. specified duration match. For instance, @option{--delete-generations=1m}
  2894. deletes generations that are more than one month old.
  2895. If the current generation matches, it is @emph{not} deleted. Also, the
  2896. zeroth generation is never deleted.
  2897. Note that deleting generations prevents rolling back to them.
  2898. Consequently, this command must be used with care.
  2899. @cindex manifest, exporting
  2900. @anchor{export-manifest}
  2901. @item --export-manifest
  2902. Write to standard output a manifest suitable for @option{--manifest}
  2903. corresponding to the chosen profile(s).
  2904. This option is meant to help you migrate from the ``imperative''
  2905. operating mode---running @command{guix install}, @command{guix upgrade},
  2906. etc.---to the declarative mode that @option{--manifest} offers.
  2907. Be aware that the resulting manifest @emph{approximates} what your
  2908. profile actually contains; for instance, depending on how your profile
  2909. was created, it can refer to packages or package versions that are not
  2910. exactly what you specified.
  2911. Keep in mind that a manifest is purely symbolic: it only contains
  2912. package names and possibly versions, and their meaning varies over time.
  2913. If you wish to ``pin'' channels to the revisions that were used to build
  2914. the profile(s), see @option{--export-channels} below.
  2915. @cindex pinning, channel revisions of a profile
  2916. @item --export-channels
  2917. Write to standard output the list of channels used by the chosen
  2918. profile(s), in a format suitable for @command{guix pull --channels} or
  2919. @command{guix time-machine --channels} (@pxref{Channels}).
  2920. Together with @option{--export-manifest}, this option provides
  2921. information allowing you to replicate the current profile
  2922. (@pxref{Replicating Guix}).
  2923. However, note that the output of this command @emph{approximates} what
  2924. was actually used to build this profile. In particular, a single
  2925. profile might have been built from several different revisions of the
  2926. same channel. In that case, @option{--export-manifest} chooses the last
  2927. one and writes the list of other revisions in a comment. If you really
  2928. need to pick packages from different channel revisions, you can use
  2929. inferiors in your manifest to do so (@pxref{Inferiors}).
  2930. Together with @option{--export-manifest}, this is a good starting point
  2931. if you are willing to migrate from the ``imperative'' model to the fully
  2932. declarative model consisting of a manifest file along with a channels
  2933. file pinning the exact channel revision(s) you want.
  2934. @end table
  2935. Finally, since @command{guix package} may actually start build
  2936. processes, it supports all the common build options (@pxref{Common Build
  2937. Options}). It also supports package transformation options, such as
  2938. @option{--with-source}, and preserves them across upgrades
  2939. (@pxref{Package Transformation Options}).
  2940. @node Substitutes
  2941. @section Substitutes
  2942. @cindex substitutes
  2943. @cindex pre-built binaries
  2944. Guix supports transparent source/binary deployment, which means that it
  2945. can either build things locally, or download pre-built items from a
  2946. server, or both. We call these pre-built items @dfn{substitutes}---they
  2947. are substitutes for local build results. In many cases, downloading a
  2948. substitute is much faster than building things locally.
  2949. Substitutes can be anything resulting from a derivation build
  2950. (@pxref{Derivations}). Of course, in the common case, they are
  2951. pre-built package binaries, but source tarballs, for instance, which
  2952. also result from derivation builds, can be available as substitutes.
  2953. @menu
  2954. * Official Substitute Server:: One particular source of substitutes.
  2955. * Substitute Server Authorization:: How to enable or disable substitutes.
  2956. * Getting Substitutes from Other Servers:: Substitute diversity.
  2957. * Substitute Authentication:: How Guix verifies substitutes.
  2958. * Proxy Settings:: How to get substitutes via proxy.
  2959. * Substitution Failure:: What happens when substitution fails.
  2960. * On Trusting Binaries:: How can you trust that binary blob?
  2961. @end menu
  2962. @node Official Substitute Server
  2963. @subsection Official Substitute Server
  2964. @cindex build farm
  2965. The @code{@value{SUBSTITUTE-SERVER}} server is a front-end to an official build farm
  2966. that builds packages from Guix continuously for some
  2967. architectures, and makes them available as substitutes. This is the
  2968. default source of substitutes; it can be overridden by passing the
  2969. @option{--substitute-urls} option either to @command{guix-daemon}
  2970. (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
  2971. or to client tools such as @command{guix package}
  2972. (@pxref{client-substitute-urls,, client @option{--substitute-urls}
  2973. option}).
  2974. Substitute URLs can be either HTTP or HTTPS.
  2975. HTTPS is recommended because communications are encrypted; conversely,
  2976. using HTTP makes all communications visible to an eavesdropper, who
  2977. could use the information gathered to determine, for instance, whether
  2978. your system has unpatched security vulnerabilities.
  2979. Substitutes from the official build farm are enabled by default when
  2980. using Guix System (@pxref{GNU Distribution}). However,
  2981. they are disabled by default when using Guix on a foreign distribution,
  2982. unless you have explicitly enabled them via one of the recommended
  2983. installation steps (@pxref{Installation}). The following paragraphs
  2984. describe how to enable or disable substitutes for the official build
  2985. farm; the same procedure can also be used to enable substitutes for any
  2986. other substitute server.
  2987. @node Substitute Server Authorization
  2988. @subsection Substitute Server Authorization
  2989. @cindex security
  2990. @cindex substitutes, authorization thereof
  2991. @cindex access control list (ACL), for substitutes
  2992. @cindex ACL (access control list), for substitutes
  2993. To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER}} or a
  2994. mirror thereof, you
  2995. must add its public key to the access control list (ACL) of archive
  2996. imports, using the @command{guix archive} command (@pxref{Invoking guix
  2997. archive}). Doing so implies that you trust @code{@value{SUBSTITUTE-SERVER}} to not
  2998. be compromised and to serve genuine substitutes.
  2999. @quotation Note
  3000. If you are using Guix System, you can skip this section: Guix System
  3001. authorizes substitutes from @code{@value{SUBSTITUTE-SERVER}} by default.
  3002. @end quotation
  3003. The public key for @code{@value{SUBSTITUTE-SERVER}} is installed along with Guix, in
  3004. @code{@var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub}, where @var{prefix} is
  3005. the installation prefix of Guix. If you installed Guix from source,
  3006. make sure you checked the GPG signature of
  3007. @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
  3008. Then, you can run something like this:
  3009. @example
  3010. # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub
  3011. @end example
  3012. Once this is in place, the output of a command like @code{guix build}
  3013. should change from something like:
  3014. @example
  3015. $ guix build emacs --dry-run
  3016. The following derivations would be built:
  3017. /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
  3018. /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
  3019. /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
  3020. /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
  3021. @dots{}
  3022. @end example
  3023. @noindent
  3024. to something like:
  3025. @example
  3026. $ guix build emacs --dry-run
  3027. 112.3 MB would be downloaded:
  3028. /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
  3029. /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
  3030. /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
  3031. /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
  3032. @dots{}
  3033. @end example
  3034. @noindent
  3035. The text changed from ``The following derivations would be built'' to
  3036. ``112.3 MB would be downloaded''. This indicates that substitutes from
  3037. @code{@value{SUBSTITUTE-SERVER}} are usable and will be downloaded, when
  3038. possible, for future builds.
  3039. @cindex substitutes, how to disable
  3040. The substitute mechanism can be disabled globally by running
  3041. @code{guix-daemon} with @option{--no-substitutes} (@pxref{Invoking
  3042. guix-daemon}). It can also be disabled temporarily by passing the
  3043. @option{--no-substitutes} option to @command{guix package},
  3044. @command{guix build}, and other command-line tools.
  3045. @node Getting Substitutes from Other Servers
  3046. @subsection Getting Substitutes from Other Servers
  3047. @cindex substitute servers, adding more
  3048. Guix can look up and fetch substitutes from several servers. This is
  3049. useful when you are using packages from additional channels for which
  3050. the official server does not have substitutes but another server
  3051. provides them. Another situation where this is useful is when you would
  3052. prefer to download from your organization's substitute server, resorting
  3053. to the official server only as a fallback or dismissing it altogether.
  3054. You can give Guix a list of substitute server URLs and it will check
  3055. them in the specified order. You also need to explicitly authorize the
  3056. public keys of substitute servers to instruct Guix to accept the
  3057. substitutes they sign.
  3058. On Guix System, this is achieved by modifying the configuration of the
  3059. @code{guix} service. Since the @code{guix} service is part of the
  3060. default lists of services, @code{%base-services} and
  3061. @code{%desktop-services}, you can use @code{modify-services} to change
  3062. its configuration and add the URLs and substitute keys that you want
  3063. (@pxref{Service Reference, @code{modify-services}}).
  3064. As an example, suppose you want to fetch substitutes from
  3065. @code{guix.example.org} and to authorize the signing key of that server,
  3066. in addition to the default @code{@value{SUBSTITUTE-SERVER}}. The
  3067. resulting operating system configuration will look something like:
  3068. @lisp
  3069. (operating-system
  3070. ;; @dots{}
  3071. (services
  3072. ;; Assume we're starting from '%desktop-services'. Replace it
  3073. ;; with the list of services you're actually using.
  3074. (modify-services %desktop-services
  3075. (guix-service-type config =>
  3076. (guix-configuration
  3077. (inherit config)
  3078. (substitute-urls
  3079. (append (list "https://guix.example.org")
  3080. %default-substitute-urls))
  3081. (authorized-keys
  3082. (append (list (local-file "./key.pub"))
  3083. %default-authorized-guix-keys)))))))
  3084. @end lisp
  3085. This assumes that the file @file{key.pub} contains the signing key of
  3086. @code{guix.example.org}. With this change in place in your operating
  3087. system configuration file (say @file{/etc/config.scm}), you can
  3088. reconfigure and restart the @code{guix-daemon} service or reboot so the
  3089. changes take effect:
  3090. @example
  3091. $ sudo guix system reconfigure /etc/config.scm
  3092. $ sudo herd restart guix-daemon
  3093. @end example
  3094. If you're running Guix on a ``foreign distro'', you would instead take
  3095. the following steps to get substitutes from additional servers:
  3096. @enumerate
  3097. @item
  3098. Edit the service configuration file for @code{guix-daemon}; when using
  3099. systemd, this is normally
  3100. @file{/etc/systemd/system/guix-daemon.service}. Add the
  3101. @option{--substitute-urls} option on the @command{guix-daemon} command
  3102. line and list the URLs of interest (@pxref{daemon-substitute-urls,
  3103. @code{guix-daemon --substitute-urls}}):
  3104. @example
  3105. @dots{} --substitute-urls='https://guix.example.org https://@value{SUBSTITUTE-SERVER}'
  3106. @end example
  3107. @item
  3108. Restart the daemon. For systemd, it goes like this:
  3109. @example
  3110. systemctl daemon-reload
  3111. systemctl restart guix-daemon.service
  3112. @end example
  3113. @item
  3114. Authorize the key of the new server (@pxref{Invoking guix archive}):
  3115. @example
  3116. guix archive --authorize < key.pub
  3117. @end example
  3118. Again this assumes @file{key.pub} contains the public key that
  3119. @code{guix.example.org} uses to sign substitutes.
  3120. @end enumerate
  3121. Now you're all set! Substitutes will be preferably taken from
  3122. @code{https://guix.example.org}, using @code{@value{SUBSTITUTE-SERVER}}
  3123. as a fallback. Of course you can list as many substitute servers as you
  3124. like, with the caveat that substitute lookup can be slowed down if too
  3125. many servers need to be contacted.
  3126. Note that there are also situations where one may want to add the URL of
  3127. a substitute server @emph{without} authorizing its key.
  3128. @xref{Substitute Authentication}, to understand this fine point.
  3129. @node Substitute Authentication
  3130. @subsection Substitute Authentication
  3131. @cindex digital signatures
  3132. Guix detects and raises an error when attempting to use a substitute
  3133. that has been tampered with. Likewise, it ignores substitutes that are
  3134. not signed, or that are not signed by one of the keys listed in the ACL.
  3135. There is one exception though: if an unauthorized server provides
  3136. substitutes that are @emph{bit-for-bit identical} to those provided by
  3137. an authorized server, then the unauthorized server becomes eligible for
  3138. downloads. For example, assume we have chosen two substitute servers
  3139. with this option:
  3140. @example
  3141. --substitute-urls="https://a.example.org https://b.example.org"
  3142. @end example
  3143. @noindent
  3144. @cindex reproducible builds
  3145. If the ACL contains only the key for @samp{b.example.org}, and if
  3146. @samp{a.example.org} happens to serve the @emph{exact same} substitutes,
  3147. then Guix will download substitutes from @samp{a.example.org} because it
  3148. comes first in the list and can be considered a mirror of
  3149. @samp{b.example.org}. In practice, independent build machines usually
  3150. produce the same binaries, thanks to bit-reproducible builds (see
  3151. below).
  3152. When using HTTPS, the server's X.509 certificate is @emph{not} validated
  3153. (in other words, the server is not authenticated), contrary to what
  3154. HTTPS clients such as Web browsers usually do. This is because Guix
  3155. authenticates substitute information itself, as explained above, which
  3156. is what we care about (whereas X.509 certificates are about
  3157. authenticating bindings between domain names and public keys).
  3158. @node Proxy Settings
  3159. @subsection Proxy Settings
  3160. @vindex http_proxy
  3161. @vindex https_proxy
  3162. Substitutes are downloaded over HTTP or HTTPS@. The @env{http_proxy} and
  3163. @env{https_proxy} environment variables can be set in the environment of
  3164. @command{guix-daemon} and are honored for downloads of substitutes.
  3165. Note that the value of those environment variables in the environment
  3166. where @command{guix build}, @command{guix package}, and other client
  3167. commands are run has @emph{absolutely no effect}.
  3168. @node Substitution Failure
  3169. @subsection Substitution Failure
  3170. Even when a substitute for a derivation is available, sometimes the
  3171. substitution attempt will fail. This can happen for a variety of
  3172. reasons: the substitute server might be offline, the substitute may
  3173. recently have been deleted, the connection might have been interrupted,
  3174. etc.
  3175. When substitutes are enabled and a substitute for a derivation is
  3176. available, but the substitution attempt fails, Guix will attempt to
  3177. build the derivation locally depending on whether or not
  3178. @option{--fallback} was given (@pxref{fallback-option,, common build
  3179. option @option{--fallback}}). Specifically, if @option{--fallback} was
  3180. omitted, then no local build will be performed, and the derivation is
  3181. considered to have failed. However, if @option{--fallback} was given,
  3182. then Guix will attempt to build the derivation locally, and the success
  3183. or failure of the derivation depends on the success or failure of the
  3184. local build. Note that when substitutes are disabled or no substitute
  3185. is available for the derivation in question, a local build will
  3186. @emph{always} be performed, regardless of whether or not
  3187. @option{--fallback} was given.
  3188. To get an idea of how many substitutes are available right now, you can
  3189. try running the @command{guix weather} command (@pxref{Invoking guix
  3190. weather}). This command provides statistics on the substitutes provided
  3191. by a server.
  3192. @node On Trusting Binaries
  3193. @subsection On Trusting Binaries
  3194. @cindex trust, of pre-built binaries
  3195. Today, each individual's control over their own computing is at the
  3196. mercy of institutions, corporations, and groups with enough power and
  3197. determination to subvert the computing infrastructure and exploit its
  3198. weaknesses. While using @code{@value{SUBSTITUTE-SERVER}} substitutes can be
  3199. convenient, we encourage users to also build on their own, or even run
  3200. their own build farm, such that @code{@value{SUBSTITUTE-SERVER}} is less of an
  3201. interesting target. One way to help is by publishing the software you
  3202. build using @command{guix publish} so that others have one more choice
  3203. of server to download substitutes from (@pxref{Invoking guix publish}).
  3204. Guix has the foundations to maximize build reproducibility
  3205. (@pxref{Features}). In most cases, independent builds of a given
  3206. package or derivation should yield bit-identical results. Thus, through
  3207. a diverse set of independent package builds, we can strengthen the
  3208. integrity of our systems. The @command{guix challenge} command aims to
  3209. help users assess substitute servers, and to assist developers in
  3210. finding out about non-deterministic package builds (@pxref{Invoking guix
  3211. challenge}). Similarly, the @option{--check} option of @command{guix
  3212. build} allows users to check whether previously-installed substitutes
  3213. are genuine by rebuilding them locally (@pxref{build-check,
  3214. @command{guix build --check}}).
  3215. In the future, we want Guix to have support to publish and retrieve
  3216. binaries to/from other users, in a peer-to-peer fashion. If you would
  3217. like to discuss this project, join us on @email{guix-devel@@gnu.org}.
  3218. @node Packages with Multiple Outputs
  3219. @section Packages with Multiple Outputs
  3220. @cindex multiple-output packages
  3221. @cindex package outputs
  3222. @cindex outputs
  3223. Often, packages defined in Guix have a single @dfn{output}---i.e., the
  3224. source package leads to exactly one directory in the store. When running
  3225. @command{guix install glibc}, one installs the default output of the
  3226. GNU libc package; the default output is called @code{out}, but its name
  3227. can be omitted as shown in this command. In this particular case, the
  3228. default output of @code{glibc} contains all the C header files, shared
  3229. libraries, static libraries, Info documentation, and other supporting
  3230. files.
  3231. Sometimes it is more appropriate to separate the various types of files
  3232. produced from a single source package into separate outputs. For
  3233. instance, the GLib C library (used by GTK+ and related packages)
  3234. installs more than 20 MiB of reference documentation as HTML pages.
  3235. To save space for users who do not need it, the documentation goes to a
  3236. separate output, called @code{doc}. To install the main GLib output,
  3237. which contains everything but the documentation, one would run:
  3238. @example
  3239. guix install glib
  3240. @end example
  3241. @cindex documentation
  3242. The command to install its documentation is:
  3243. @example
  3244. guix install glib:doc
  3245. @end example
  3246. Some packages install programs with different ``dependency footprints''.
  3247. For instance, the WordNet package installs both command-line tools and
  3248. graphical user interfaces (GUIs). The former depend solely on the C
  3249. library, whereas the latter depend on Tcl/Tk and the underlying X
  3250. libraries. In this case, we leave the command-line tools in the default
  3251. output, whereas the GUIs are in a separate output. This allows users
  3252. who do not need the GUIs to save space. The @command{guix size} command
  3253. can help find out about such situations (@pxref{Invoking guix size}).
  3254. @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
  3255. There are several such multiple-output packages in the GNU distribution.
  3256. Other conventional output names include @code{lib} for libraries and
  3257. possibly header files, @code{bin} for stand-alone programs, and
  3258. @code{debug} for debugging information (@pxref{Installing Debugging
  3259. Files}). The outputs of a packages are listed in the third column of
  3260. the output of @command{guix package --list-available} (@pxref{Invoking
  3261. guix package}).
  3262. @node Invoking guix gc
  3263. @section Invoking @command{guix gc}
  3264. @cindex garbage collector
  3265. @cindex disk space
  3266. Packages that are installed, but not used, may be @dfn{garbage-collected}.
  3267. The @command{guix gc} command allows users to explicitly run the garbage
  3268. collector to reclaim space from the @file{/gnu/store} directory. It is
  3269. the @emph{only} way to remove files from @file{/gnu/store}---removing
  3270. files or directories manually may break it beyond repair!
  3271. @cindex GC roots
  3272. @cindex garbage collector roots
  3273. The garbage collector has a set of known @dfn{roots}: any file under
  3274. @file{/gnu/store} reachable from a root is considered @dfn{live} and
  3275. cannot be deleted; any other file is considered @dfn{dead} and may be
  3276. deleted. The set of garbage collector roots (``GC roots'' for short)
  3277. includes default user profiles; by default, the symlinks under
  3278. @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
  3279. added with @command{guix build --root}, for example (@pxref{Invoking
  3280. guix build}). The @command{guix gc --list-roots} command lists them.
  3281. Prior to running @code{guix gc --collect-garbage} to make space, it is
  3282. often useful to remove old generations from user profiles; that way, old
  3283. package builds referenced by those generations can be reclaimed. This
  3284. is achieved by running @code{guix package --delete-generations}
  3285. (@pxref{Invoking guix package}).
  3286. Our recommendation is to run a garbage collection periodically, or when
  3287. you are short on disk space. For instance, to guarantee that at least
  3288. 5@tie{}GB are available on your disk, simply run:
  3289. @example
  3290. guix gc -F 5G
  3291. @end example
  3292. It is perfectly safe to run as a non-interactive periodic job
  3293. (@pxref{Scheduled Job Execution}, for how to set up such a job).
  3294. Running @command{guix gc} with no arguments will collect as
  3295. much garbage as it can, but that is often inconvenient: you may find
  3296. yourself having to rebuild or re-download software that is ``dead'' from
  3297. the GC viewpoint but that is necessary to build other pieces of
  3298. software---e.g., the compiler tool chain.
  3299. The @command{guix gc} command has three modes of operation: it can be
  3300. used to garbage-collect any dead files (the default), to delete specific
  3301. files (the @option{--delete} option), to print garbage-collector
  3302. information, or for more advanced queries. The garbage collection
  3303. options are as follows:
  3304. @table @code
  3305. @item --collect-garbage[=@var{min}]
  3306. @itemx -C [@var{min}]
  3307. Collect garbage---i.e., unreachable @file{/gnu/store} files and
  3308. sub-directories. This is the default operation when no option is
  3309. specified.
  3310. When @var{min} is given, stop once @var{min} bytes have been collected.
  3311. @var{min} may be a number of bytes, or it may include a unit as a
  3312. suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
  3313. (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
  3314. When @var{min} is omitted, collect all the garbage.
  3315. @item --free-space=@var{free}
  3316. @itemx -F @var{free}
  3317. Collect garbage until @var{free} space is available under
  3318. @file{/gnu/store}, if possible; @var{free} denotes storage space, such
  3319. as @code{500MiB}, as described above.
  3320. When @var{free} or more is already available in @file{/gnu/store}, do
  3321. nothing and exit immediately.
  3322. @item --delete-generations[=@var{duration}]
  3323. @itemx -d [@var{duration}]
  3324. Before starting the garbage collection process, delete all the generations
  3325. older than @var{duration}, for all the user profiles; when run as root, this
  3326. applies to all the profiles @emph{of all the users}.
  3327. For example, this command deletes all the generations of all your profiles
  3328. that are older than 2 months (except generations that are current), and then
  3329. proceeds to free space until at least 10 GiB are available:
  3330. @example
  3331. guix gc -d 2m -F 10G
  3332. @end example
  3333. @item --delete
  3334. @itemx -D
  3335. Attempt to delete all the store files and directories specified as
  3336. arguments. This fails if some of the files are not in the store, or if
  3337. they are still live.
  3338. @item --list-failures
  3339. List store items corresponding to cached build failures.
  3340. This prints nothing unless the daemon was started with
  3341. @option{--cache-failures} (@pxref{Invoking guix-daemon,
  3342. @option{--cache-failures}}).
  3343. @item --list-roots
  3344. List the GC roots owned by the user; when run as root, list @emph{all} the GC
  3345. roots.
  3346. @item --list-busy
  3347. List store items in use by currently running processes. These store
  3348. items are effectively considered GC roots: they cannot be deleted.
  3349. @item --clear-failures
  3350. Remove the specified store items from the failed-build cache.
  3351. Again, this option only makes sense when the daemon is started with
  3352. @option{--cache-failures}. Otherwise, it does nothing.
  3353. @item --list-dead
  3354. Show the list of dead files and directories still present in the
  3355. store---i.e., files and directories no longer reachable from any root.
  3356. @item --list-live
  3357. Show the list of live store files and directories.
  3358. @end table
  3359. In addition, the references among existing store files can be queried:
  3360. @table @code
  3361. @item --references
  3362. @itemx --referrers
  3363. @cindex package dependencies
  3364. List the references (respectively, the referrers) of store files given
  3365. as arguments.
  3366. @item --requisites
  3367. @itemx -R
  3368. @cindex closure
  3369. List the requisites of the store files passed as arguments. Requisites
  3370. include the store files themselves, their references, and the references
  3371. of these, recursively. In other words, the returned list is the
  3372. @dfn{transitive closure} of the store files.
  3373. @xref{Invoking guix size}, for a tool to profile the size of the closure
  3374. of an element. @xref{Invoking guix graph}, for a tool to visualize
  3375. the graph of references.
  3376. @item --derivers
  3377. @cindex derivation
  3378. Return the derivation(s) leading to the given store items
  3379. (@pxref{Derivations}).
  3380. For example, this command:
  3381. @example
  3382. guix gc --derivers `guix package -I ^emacs$ | cut -f4`
  3383. @end example
  3384. @noindent
  3385. returns the @file{.drv} file(s) leading to the @code{emacs} package
  3386. installed in your profile.
  3387. Note that there may be zero matching @file{.drv} files, for instance
  3388. because these files have been garbage-collected. There can also be more
  3389. than one matching @file{.drv} due to fixed-output derivations.
  3390. @end table
  3391. Lastly, the following options allow you to check the integrity of the
  3392. store and to control disk usage.
  3393. @table @option
  3394. @item --verify[=@var{options}]
  3395. @cindex integrity, of the store
  3396. @cindex integrity checking
  3397. Verify the integrity of the store.
  3398. By default, make sure that all the store items marked as valid in the
  3399. database of the daemon actually exist in @file{/gnu/store}.
  3400. When provided, @var{options} must be a comma-separated list containing one
  3401. or more of @code{contents} and @code{repair}.
  3402. When passing @option{--verify=contents}, the daemon computes the
  3403. content hash of each store item and compares it against its hash in the
  3404. database. Hash mismatches are reported as data corruptions. Because it
  3405. traverses @emph{all the files in the store}, this command can take a
  3406. long time, especially on systems with a slow disk drive.
  3407. @cindex repairing the store
  3408. @cindex corruption, recovering from
  3409. Using @option{--verify=repair} or @option{--verify=contents,repair}
  3410. causes the daemon to try to repair corrupt store items by fetching
  3411. substitutes for them (@pxref{Substitutes}). Because repairing is not
  3412. atomic, and thus potentially dangerous, it is available only to the
  3413. system administrator. A lightweight alternative, when you know exactly
  3414. which items in the store are corrupt, is @command{guix build --repair}
  3415. (@pxref{Invoking guix build}).
  3416. @item --optimize
  3417. @cindex deduplication
  3418. Optimize the store by hard-linking identical files---this is
  3419. @dfn{deduplication}.
  3420. The daemon performs deduplication after each successful build or archive
  3421. import, unless it was started with @option{--disable-deduplication}
  3422. (@pxref{Invoking guix-daemon, @option{--disable-deduplication}}). Thus,
  3423. this option is primarily useful when the daemon was running with
  3424. @option{--disable-deduplication}.
  3425. @end table
  3426. @node Invoking guix pull
  3427. @section Invoking @command{guix pull}
  3428. @cindex upgrading Guix
  3429. @cindex updating Guix
  3430. @cindex @command{guix pull}
  3431. @cindex pull
  3432. @cindex security, @command{guix pull}
  3433. @cindex authenticity, of code obtained with @command{guix pull}
  3434. Packages are installed or upgraded to the latest version available in
  3435. the distribution currently available on your local machine. To update
  3436. that distribution, along with the Guix tools, you must run @command{guix
  3437. pull}: the command downloads the latest Guix source code and package
  3438. descriptions, and deploys it. Source code is downloaded from a
  3439. @uref{https://git-scm.com, Git} repository, by default the official
  3440. GNU@tie{}Guix repository, though this can be customized. @command{guix
  3441. pull} ensures that the code it downloads is @emph{authentic} by
  3442. verifying that commits are signed by Guix developers.
  3443. Specifically, @command{guix pull} downloads code from the @dfn{channels}
  3444. (@pxref{Channels}) specified by one of the followings, in this order:
  3445. @enumerate
  3446. @item
  3447. the @option{--channels} option;
  3448. @item
  3449. the user's @file{~/.config/guix/channels.scm} file;
  3450. @item
  3451. the system-wide @file{/etc/guix/channels.scm} file;
  3452. @item
  3453. the built-in default channels specified in the @code{%default-channels}
  3454. variable.
  3455. @end enumerate
  3456. On completion, @command{guix package} will use packages and package
  3457. versions from this just-retrieved copy of Guix. Not only that, but all
  3458. the Guix commands and Scheme modules will also be taken from that latest
  3459. version. New @command{guix} sub-commands added by the update also
  3460. become available.
  3461. Any user can update their Guix copy using @command{guix pull}, and the
  3462. effect is limited to the user who ran @command{guix pull}. For
  3463. instance, when user @code{root} runs @command{guix pull}, this has no
  3464. effect on the version of Guix that user @code{alice} sees, and vice
  3465. versa.
  3466. The result of running @command{guix pull} is a @dfn{profile} available
  3467. under @file{~/.config/guix/current} containing the latest Guix. Thus,
  3468. make sure to add it to the beginning of your search path so that you use
  3469. the latest version, and similarly for the Info manual
  3470. (@pxref{Documentation}):
  3471. @example
  3472. export PATH="$HOME/.config/guix/current/bin:$PATH"
  3473. export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
  3474. @end example
  3475. The @option{--list-generations} or @option{-l} option lists past generations
  3476. produced by @command{guix pull}, along with details about their provenance:
  3477. @example
  3478. $ guix pull -l
  3479. Generation 1 Jun 10 2018 00:18:18
  3480. guix 65956ad
  3481. repository URL: https://git.savannah.gnu.org/git/guix.git
  3482. branch: origin/master
  3483. commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
  3484. Generation 2 Jun 11 2018 11:02:49
  3485. guix e0cc7f6
  3486. repository URL: https://git.savannah.gnu.org/git/guix.git
  3487. branch: origin/master
  3488. commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
  3489. 2 new packages: keepalived, libnfnetlink
  3490. 6 packages upgraded: emacs-nix-mode@@2.0.4,
  3491. guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
  3492. heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
  3493. Generation 3 Jun 13 2018 23:31:07 (current)
  3494. guix 844cc1c
  3495. repository URL: https://git.savannah.gnu.org/git/guix.git
  3496. branch: origin/master
  3497. commit: 844cc1c8f394f03b404c5bb3aee086922373490c
  3498. 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
  3499. 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
  3500. @end example
  3501. @xref{Invoking guix describe, @command{guix describe}}, for other ways to
  3502. describe the current status of Guix.
  3503. This @code{~/.config/guix/current} profile works exactly like the profiles
  3504. created by @command{guix package} (@pxref{Invoking guix package}). That
  3505. is, you can list generations, roll back to the previous
  3506. generation---i.e., the previous Guix---and so on:
  3507. @example
  3508. $ guix pull --roll-back
  3509. switched from generation 3 to 2
  3510. $ guix pull --delete-generations=1
  3511. deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
  3512. @end example
  3513. You can also use @command{guix package} (@pxref{Invoking guix package})
  3514. to manage the profile by naming it explicitly:
  3515. @example
  3516. $ guix package -p ~/.config/guix/current --roll-back
  3517. switched from generation 3 to 2
  3518. $ guix package -p ~/.config/guix/current --delete-generations=1
  3519. deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
  3520. @end example
  3521. The @command{guix pull} command is usually invoked with no arguments,
  3522. but it supports the following options:
  3523. @table @code
  3524. @item --url=@var{url}
  3525. @itemx --commit=@var{commit}
  3526. @itemx --branch=@var{branch}
  3527. Download code for the @code{guix} channel from the specified @var{url}, at the
  3528. given @var{commit} (a valid Git commit ID represented as a hexadecimal
  3529. string), or @var{branch}.
  3530. @cindex @file{channels.scm}, configuration file
  3531. @cindex configuration file for channels
  3532. These options are provided for convenience, but you can also specify your
  3533. configuration in the @file{~/.config/guix/channels.scm} file or using the
  3534. @option{--channels} option (see below).
  3535. @item --channels=@var{file}
  3536. @itemx -C @var{file}
  3537. Read the list of channels from @var{file} instead of
  3538. @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
  3539. @var{file} must contain Scheme code that
  3540. evaluates to a list of channel objects. @xref{Channels}, for more
  3541. information.
  3542. @cindex channel news
  3543. @item --news
  3544. @itemx -N
  3545. Display the list of packages added or upgraded since the previous
  3546. generation, as well as, occasionally, news written by channel authors
  3547. for their users (@pxref{Channels, Writing Channel News}).
  3548. The package information is the same as displayed upon @command{guix
  3549. pull} completion, but without ellipses; it is also similar to the output
  3550. of @command{guix pull -l} for the last generation (see below).
  3551. @item --list-generations[=@var{pattern}]
  3552. @itemx -l [@var{pattern}]
  3553. List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
  3554. is provided, the subset of generations that match @var{pattern}.
  3555. The syntax of @var{pattern} is the same as with @code{guix package
  3556. --list-generations} (@pxref{Invoking guix package}).
  3557. @item --roll-back
  3558. @cindex rolling back
  3559. @cindex undoing transactions
  3560. @cindex transactions, undoing
  3561. Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
  3562. undo the last transaction.
  3563. @item --switch-generation=@var{pattern}
  3564. @itemx -S @var{pattern}
  3565. @cindex generations
  3566. Switch to a particular generation defined by @var{pattern}.
  3567. @var{pattern} may be either a generation number or a number prefixed
  3568. with ``+'' or ``-''. The latter means: move forward/backward by a
  3569. specified number of generations. For example, if you want to return to
  3570. the latest generation after @option{--roll-back}, use
  3571. @option{--switch-generation=+1}.
  3572. @item --delete-generations[=@var{pattern}]
  3573. @itemx -d [@var{pattern}]
  3574. When @var{pattern} is omitted, delete all generations except the current
  3575. one.
  3576. This command accepts the same patterns as @option{--list-generations}.
  3577. When @var{pattern} is specified, delete the matching generations. When
  3578. @var{pattern} specifies a duration, generations @emph{older} than the
  3579. specified duration match. For instance, @option{--delete-generations=1m}
  3580. deletes generations that are more than one month old.
  3581. If the current generation matches, it is @emph{not} deleted.
  3582. Note that deleting generations prevents rolling back to them.
  3583. Consequently, this command must be used with care.
  3584. @xref{Invoking guix describe}, for a way to display information about the
  3585. current generation only.
  3586. @item --profile=@var{profile}
  3587. @itemx -p @var{profile}
  3588. Use @var{profile} instead of @file{~/.config/guix/current}.
  3589. @item --dry-run
  3590. @itemx -n
  3591. Show which channel commit(s) would be used and what would be built or
  3592. substituted but do not actually do it.
  3593. @item --allow-downgrades
  3594. Allow pulling older or unrelated revisions of channels than those
  3595. currently in use.
  3596. @cindex downgrade attacks, protection against
  3597. By default, @command{guix pull} protects against so-called ``downgrade
  3598. attacks'' whereby the Git repository of a channel would be reset to an
  3599. earlier or unrelated revision of itself, potentially leading you to
  3600. install older, known-vulnerable versions of software packages.
  3601. @quotation Note
  3602. Make sure you understand its security implications before using
  3603. @option{--allow-downgrades}.
  3604. @end quotation
  3605. @item --disable-authentication
  3606. Allow pulling channel code without authenticating it.
  3607. @cindex authentication, of channel code
  3608. By default, @command{guix pull} authenticates code downloaded from
  3609. channels by verifying that its commits are signed by authorized
  3610. developers, and raises an error if this is not the case. This option
  3611. instructs it to not perform any such verification.
  3612. @quotation Note
  3613. Make sure you understand its security implications before using
  3614. @option{--disable-authentication}.
  3615. @end quotation
  3616. @item --system=@var{system}
  3617. @itemx -s @var{system}
  3618. Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
  3619. the system type of the build host.
  3620. @item --bootstrap
  3621. Use the bootstrap Guile to build the latest Guix. This option is only
  3622. useful to Guix developers.
  3623. @end table
  3624. The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
  3625. repository and branch to pull from, as well as @emph{additional} repositories
  3626. containing package modules that should be deployed. @xref{Channels}, for more
  3627. information.
  3628. In addition, @command{guix pull} supports all the common build options
  3629. (@pxref{Common Build Options}).
  3630. @node Invoking guix time-machine
  3631. @section Invoking @command{guix time-machine}
  3632. @cindex @command{guix time-machine}
  3633. @cindex pinning, channels
  3634. @cindex replicating Guix
  3635. @cindex reproducibility, of Guix
  3636. The @command{guix time-machine} command provides access to other
  3637. revisions of Guix, for example to install older versions of packages,
  3638. or to reproduce a computation in an identical environment. The revision
  3639. of Guix to be used is defined by a commit or by a channel
  3640. description file created by @command{guix describe}
  3641. (@pxref{Invoking guix describe}).
  3642. The general syntax is:
  3643. @example
  3644. guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
  3645. @end example
  3646. where @var{command} and @var{arg}@dots{} are passed unmodified to the
  3647. @command{guix} command of the specified revision. The @var{options} that define
  3648. this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
  3649. @table @code
  3650. @item --url=@var{url}
  3651. @itemx --commit=@var{commit}
  3652. @itemx --branch=@var{branch}
  3653. Use the @code{guix} channel from the specified @var{url}, at the
  3654. given @var{commit} (a valid Git commit ID represented as a hexadecimal
  3655. string), or @var{branch}.
  3656. @item --channels=@var{file}
  3657. @itemx -C @var{file}
  3658. Read the list of channels from @var{file}. @var{file} must contain
  3659. Scheme code that evaluates to a list of channel objects.
  3660. @xref{Channels} for more information.
  3661. @end table
  3662. As for @command{guix pull}, the absence of any options means that the
  3663. latest commit on the master branch will be used. The command
  3664. @example
  3665. guix time-machine -- build hello
  3666. @end example
  3667. will thus build the package @code{hello} as defined in the master branch,
  3668. which is in general a newer revision of Guix than you have installed.
  3669. Time travel works in both directions!
  3670. Note that @command{guix time-machine} can trigger builds of channels and
  3671. their dependencies, and these are controlled by the standard build
  3672. options (@pxref{Common Build Options}).
  3673. @node Inferiors
  3674. @section Inferiors
  3675. @c TODO: Remove this once we're more confident about API stability.
  3676. @quotation Note
  3677. The functionality described here is a ``technology preview'' as of version
  3678. @value{VERSION}. As such, the interface is subject to change.
  3679. @end quotation
  3680. @cindex inferiors
  3681. @cindex composition of Guix revisions
  3682. Sometimes you might need to mix packages from the revision of Guix you're
  3683. currently running with packages available in a different revision of Guix.
  3684. Guix @dfn{inferiors} allow you to achieve that by composing different Guix
  3685. revisions in arbitrary ways.
  3686. @cindex inferior packages
  3687. Technically, an ``inferior'' is essentially a separate Guix process connected
  3688. to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
  3689. @code{(guix inferior)} module allows you to create inferiors and to
  3690. communicate with them. It also provides a high-level interface to browse and
  3691. manipulate the packages that an inferior provides---@dfn{inferior packages}.
  3692. When combined with channels (@pxref{Channels}), inferiors provide a simple way
  3693. to interact with a separate revision of Guix. For example, let's assume you
  3694. want to install in your profile the current @code{guile} package, along with
  3695. the @code{guile-json} as it existed in an older revision of Guix---perhaps
  3696. because the newer @code{guile-json} has an incompatible API and you want to
  3697. run your code against the old API@. To do that, you could write a manifest for
  3698. use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
  3699. manifest, you would create an inferior for that old Guix revision you care
  3700. about, and you would look up the @code{guile-json} package in the inferior:
  3701. @lisp
  3702. (use-modules (guix inferior) (guix channels)
  3703. (srfi srfi-1)) ;for 'first'
  3704. (define channels
  3705. ;; This is the old revision from which we want to
  3706. ;; extract guile-json.
  3707. (list (channel
  3708. (name 'guix)
  3709. (url "https://git.savannah.gnu.org/git/guix.git")
  3710. (commit
  3711. "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
  3712. (define inferior
  3713. ;; An inferior representing the above revision.
  3714. (inferior-for-channels channels))
  3715. ;; Now create a manifest with the current "guile" package
  3716. ;; and the old "guile-json" package.
  3717. (packages->manifest
  3718. (list (first (lookup-inferior-packages inferior "guile-json"))
  3719. (specification->package "guile")))
  3720. @end lisp
  3721. On its first run, @command{guix package --manifest} might have to build the
  3722. channel you specified before it can create the inferior; subsequent runs will
  3723. be much faster because the Guix revision will be cached.
  3724. The @code{(guix inferior)} module provides the following procedures to open an
  3725. inferior:
  3726. @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
  3727. [#:cache-directory] [#:ttl]
  3728. Return an inferior for @var{channels}, a list of channels. Use the cache at
  3729. @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
  3730. This procedure opens a new connection to the build daemon.
  3731. As a side effect, this procedure may build or substitute binaries for
  3732. @var{channels}, which can take time.
  3733. @end deffn
  3734. @deffn {Scheme Procedure} open-inferior @var{directory} @
  3735. [#:command "bin/guix"]
  3736. Open the inferior Guix in @var{directory}, running
  3737. @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
  3738. the inferior could not be launched.
  3739. @end deffn
  3740. @cindex inferior packages
  3741. The procedures listed below allow you to obtain and manipulate inferior
  3742. packages.
  3743. @deffn {Scheme Procedure} inferior-packages @var{inferior}
  3744. Return the list of packages known to @var{inferior}.
  3745. @end deffn
  3746. @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
  3747. [@var{version}]
  3748. Return the sorted list of inferior packages matching @var{name} in
  3749. @var{inferior}, with highest version numbers first. If @var{version} is true,
  3750. return only packages with a version number prefixed by @var{version}.
  3751. @end deffn
  3752. @deffn {Scheme Procedure} inferior-package? @var{obj}
  3753. Return true if @var{obj} is an inferior package.
  3754. @end deffn
  3755. @deffn {Scheme Procedure} inferior-package-name @var{package}
  3756. @deffnx {Scheme Procedure} inferior-package-version @var{package}
  3757. @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
  3758. @deffnx {Scheme Procedure} inferior-package-description @var{package}
  3759. @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
  3760. @deffnx {Scheme Procedure} inferior-package-location @var{package}
  3761. @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
  3762. @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
  3763. @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
  3764. @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
  3765. @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
  3766. @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
  3767. @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
  3768. These procedures are the counterpart of package record accessors
  3769. (@pxref{package Reference}). Most of them work by querying the inferior
  3770. @var{package} comes from, so the inferior must still be live when you call
  3771. these procedures.
  3772. @end deffn
  3773. Inferior packages can be used transparently like any other package or
  3774. file-like object in G-expressions (@pxref{G-Expressions}). They are also
  3775. transparently handled by the @code{packages->manifest} procedure, which is
  3776. commonly use in manifests (@pxref{Invoking guix package, the
  3777. @option{--manifest} option of @command{guix package}}). Thus you can insert
  3778. an inferior package pretty much anywhere you would insert a regular package:
  3779. in manifests, in the @code{packages} field of your @code{operating-system}
  3780. declaration, and so on.
  3781. @node Invoking guix describe
  3782. @section Invoking @command{guix describe}
  3783. @cindex reproducibility
  3784. @cindex replicating Guix
  3785. Often you may want to answer questions like: ``Which revision of Guix am I
  3786. using?'' or ``Which channels am I using?'' This is useful information in many
  3787. situations: if you want to @emph{replicate} an environment on a different
  3788. machine or user account, if you want to report a bug or to determine what
  3789. change in the channels you are using caused it, or if you want to record your
  3790. system state for reproducibility purposes. The @command{guix describe}
  3791. command answers these questions.
  3792. When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
  3793. displays the channel(s) that it was built from, including their repository URL
  3794. and commit IDs (@pxref{Channels}):
  3795. @example
  3796. $ guix describe
  3797. Generation 10 Sep 03 2018 17:32:44 (current)
  3798. guix e0fa68c
  3799. repository URL: https://git.savannah.gnu.org/git/guix.git
  3800. branch: master
  3801. commit: e0fa68c7718fffd33d81af415279d6ddb518f727
  3802. @end example
  3803. If you're familiar with the Git version control system, this is similar in
  3804. spirit to @command{git describe}; the output is also similar to that of
  3805. @command{guix pull --list-generations}, but limited to the current generation
  3806. (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
  3807. the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
  3808. information is all it takes to describe the revision of Guix you're using, and
  3809. also to replicate it.
  3810. To make it easier to replicate Guix, @command{guix describe} can also be asked
  3811. to return a list of channels instead of the human-readable description above:
  3812. @example
  3813. $ guix describe -f channels
  3814. (list (channel
  3815. (name 'guix)
  3816. (url "https://git.savannah.gnu.org/git/guix.git")
  3817. (commit
  3818. "e0fa68c7718fffd33d81af415279d6ddb518f727")
  3819. (introduction
  3820. (make-channel-introduction
  3821. "9edb3f66fd807b096b48283debdcddccfea34bad"
  3822. (openpgp-fingerprint
  3823. "BBB0 2DDF 2CEA F6A8 0D1D E643 A2A0 6DF2 A33A 54FA")))))
  3824. @end example
  3825. @noindent
  3826. You can save this to a file and feed it to @command{guix pull -C} on some
  3827. other machine or at a later point in time, which will instantiate @emph{this
  3828. exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
  3829. From there on, since you're able to deploy the same revision of Guix, you can
  3830. just as well @emph{replicate a complete software environment}. We humbly
  3831. think that this is @emph{awesome}, and we hope you'll like it too!
  3832. The details of the options supported by @command{guix describe} are as
  3833. follows:
  3834. @table @code
  3835. @item --format=@var{format}
  3836. @itemx -f @var{format}
  3837. Produce output in the specified @var{format}, one of:
  3838. @table @code
  3839. @item human
  3840. produce human-readable output;
  3841. @item channels
  3842. produce a list of channel specifications that can be passed to @command{guix
  3843. pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
  3844. guix pull});
  3845. @item channels-sans-intro
  3846. like @code{channels}, but omit the @code{introduction} field; use it to
  3847. produce a channel specification suitable for Guix version 1.1.0 or
  3848. earlier---the @code{introduction} field has to do with channel
  3849. authentication (@pxref{Channels, Channel Authentication}) and is not
  3850. supported by these older versions;
  3851. @item json
  3852. @cindex JSON
  3853. produce a list of channel specifications in JSON format;
  3854. @item recutils
  3855. produce a list of channel specifications in Recutils format.
  3856. @end table
  3857. @item --list-formats
  3858. Display available formats for @option{--format} option.
  3859. @item --profile=@var{profile}
  3860. @itemx -p @var{profile}
  3861. Display information about @var{profile}.
  3862. @end table
  3863. @node Invoking guix archive
  3864. @section Invoking @command{guix archive}
  3865. @cindex @command{guix archive}
  3866. @cindex archive
  3867. The @command{guix archive} command allows users to @dfn{export} files
  3868. from the store into a single archive, and to later @dfn{import} them on
  3869. a machine that runs Guix.
  3870. In particular, it allows store files to be transferred from one machine
  3871. to the store on another machine.
  3872. @quotation Note
  3873. If you're looking for a way to produce archives in a format suitable for
  3874. tools other than Guix, @pxref{Invoking guix pack}.
  3875. @end quotation
  3876. @cindex exporting store items
  3877. To export store files as an archive to standard output, run:
  3878. @example
  3879. guix archive --export @var{options} @var{specifications}...
  3880. @end example
  3881. @var{specifications} may be either store file names or package
  3882. specifications, as for @command{guix package} (@pxref{Invoking guix
  3883. package}). For instance, the following command creates an archive
  3884. containing the @code{gui} output of the @code{git} package and the main
  3885. output of @code{emacs}:
  3886. @example
  3887. guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
  3888. @end example
  3889. If the specified packages are not built yet, @command{guix archive}
  3890. automatically builds them. The build process may be controlled with the
  3891. common build options (@pxref{Common Build Options}).
  3892. To transfer the @code{emacs} package to a machine connected over SSH,
  3893. one would run:
  3894. @example
  3895. guix archive --export -r emacs | ssh the-machine guix archive --import
  3896. @end example
  3897. @noindent
  3898. Similarly, a complete user profile may be transferred from one machine
  3899. to another like this:
  3900. @example
  3901. guix archive --export -r $(readlink -f ~/.guix-profile) | \
  3902. ssh the-machine guix archive --import
  3903. @end example
  3904. @noindent
  3905. However, note that, in both examples, all of @code{emacs} and the
  3906. profile as well as all of their dependencies are transferred (due to
  3907. @option{-r}), regardless of what is already available in the store on
  3908. the target machine. The @option{--missing} option can help figure out
  3909. which items are missing from the target store. The @command{guix copy}
  3910. command simplifies and optimizes this whole process, so this is probably
  3911. what you should use in this case (@pxref{Invoking guix copy}).
  3912. @cindex nar, archive format
  3913. @cindex normalized archive (nar)
  3914. @cindex nar bundle, archive format
  3915. Each store item is written in the @dfn{normalized archive} or @dfn{nar}
  3916. format (described below), and the output of @command{guix archive
  3917. --export} (and input of @command{guix archive --import}) is a @dfn{nar
  3918. bundle}.
  3919. The nar format is
  3920. comparable in spirit to `tar', but with differences
  3921. that make it more appropriate for our purposes. First, rather than
  3922. recording all Unix metadata for each file, the nar format only mentions
  3923. the file type (regular, directory, or symbolic link); Unix permissions
  3924. and owner/group are dismissed. Second, the order in which directory
  3925. entries are stored always follows the order of file names according to
  3926. the C locale collation order. This makes archive production fully
  3927. deterministic.
  3928. That nar bundle format is essentially the concatenation of zero or more
  3929. nars along with metadata for each store item it contains: its file name,
  3930. references, corresponding derivation, and a digital signature.
  3931. When exporting, the daemon digitally signs the contents of the archive,
  3932. and that digital signature is appended. When importing, the daemon
  3933. verifies the signature and rejects the import in case of an invalid
  3934. signature or if the signing key is not authorized.
  3935. @c FIXME: Add xref to daemon doc about signatures.
  3936. The main options are:
  3937. @table @code
  3938. @item --export
  3939. Export the specified store files or packages (see below). Write the
  3940. resulting archive to the standard output.
  3941. Dependencies are @emph{not} included in the output, unless
  3942. @option{--recursive} is passed.
  3943. @item -r
  3944. @itemx --recursive
  3945. When combined with @option{--export}, this instructs @command{guix archive}
  3946. to include dependencies of the given items in the archive. Thus, the
  3947. resulting archive is self-contained: it contains the closure of the
  3948. exported store items.
  3949. @item --import
  3950. Read an archive from the standard input, and import the files listed
  3951. therein into the store. Abort if the archive has an invalid digital
  3952. signature, or if it is signed by a public key not among the authorized
  3953. keys (see @option{--authorize} below).
  3954. @item --missing
  3955. Read a list of store file names from the standard input, one per line,
  3956. and write on the standard output the subset of these files missing from
  3957. the store.
  3958. @item --generate-key[=@var{parameters}]
  3959. @cindex signing, archives
  3960. Generate a new key pair for the daemon. This is a prerequisite before
  3961. archives can be exported with @option{--export}. This
  3962. operation is usually instantaneous but it can take time if the system's
  3963. entropy pool needs to be refilled. On Guix System,
  3964. @code{guix-service-type} takes care of generating this key pair the
  3965. first boot.
  3966. The generated key pair is typically stored under @file{/etc/guix}, in
  3967. @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
  3968. key, which must be kept secret). When @var{parameters} is omitted,
  3969. an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
  3970. versions before 1.6.0, it is a 4096-bit RSA key.
  3971. Alternatively, @var{parameters} can specify
  3972. @code{genkey} parameters suitable for Libgcrypt (@pxref{General
  3973. public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
  3974. Libgcrypt Reference Manual}).
  3975. @item --authorize
  3976. @cindex authorizing, archives
  3977. Authorize imports signed by the public key passed on standard input.
  3978. The public key must be in ``s-expression advanced format''---i.e., the
  3979. same format as the @file{signing-key.pub} file.
  3980. The list of authorized keys is kept in the human-editable file
  3981. @file{/etc/guix/acl}. The file contains
  3982. @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
  3983. s-expressions''} and is structured as an access-control list in the
  3984. @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
  3985. (SPKI)}.
  3986. @item --extract=@var{directory}
  3987. @itemx -x @var{directory}
  3988. Read a single-item archive as served by substitute servers
  3989. (@pxref{Substitutes}) and extract it to @var{directory}. This is a
  3990. low-level operation needed in only very narrow use cases; see below.
  3991. For example, the following command extracts the substitute for Emacs
  3992. served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
  3993. @example
  3994. $ wget -O - \
  3995. https://@value{SUBSTITUTE-SERVER}/nar/gzip/@dots{}-emacs-24.5 \
  3996. | gunzip | guix archive -x /tmp/emacs
  3997. @end example
  3998. Single-item archives are different from multiple-item archives produced
  3999. by @command{guix archive --export}; they contain a single store item,
  4000. and they do @emph{not} embed a signature. Thus this operation does
  4001. @emph{no} signature verification and its output should be considered
  4002. unsafe.
  4003. The primary purpose of this operation is to facilitate inspection of
  4004. archive contents coming from possibly untrusted substitute servers
  4005. (@pxref{Invoking guix challenge}).
  4006. @item --list
  4007. @itemx -t
  4008. Read a single-item archive as served by substitute servers
  4009. (@pxref{Substitutes}) and print the list of files it contains, as in
  4010. this example:
  4011. @example
  4012. $ wget -O - \
  4013. https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-emacs-26.3 \
  4014. | lzip -d | guix archive -t
  4015. @end example
  4016. @end table
  4017. @c *********************************************************************
  4018. @node Channels
  4019. @chapter Channels
  4020. @cindex channels
  4021. @cindex @file{channels.scm}, configuration file
  4022. @cindex configuration file for channels
  4023. @cindex @command{guix pull}, configuration file
  4024. @cindex configuration of @command{guix pull}
  4025. Guix and its package collection are updated by running @command{guix pull}
  4026. (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
  4027. deploys Guix itself from the official GNU@tie{}Guix repository. This can be
  4028. customized by defining @dfn{channels} in the
  4029. @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
  4030. of a Git repository to be deployed, and @command{guix pull} can be instructed
  4031. to pull from one or more channels. In other words, channels can be used
  4032. to @emph{customize} and to @emph{extend} Guix, as we will see below.
  4033. Guix is able to take into account security concerns and deal with authenticated
  4034. updates.
  4035. @menu
  4036. * Specifying Additional Channels:: Extending the package collection.
  4037. * Using a Custom Guix Channel:: Using a customized Guix.
  4038. * Replicating Guix:: Running the @emph{exact same} Guix.
  4039. * Channel Authentication:: How Guix verifies what it fetches.
  4040. * Creating a Channel:: How to write your custom channel.
  4041. * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
  4042. * Declaring Channel Dependencies:: How to depend on other channels.
  4043. * Specifying Channel Authorizations:: Defining channel authors authorizations.
  4044. * Primary URL:: Distinguishing mirror to original.
  4045. * Writing Channel News:: Communicating information to channel's users.
  4046. * Channels with Substitutes:: Using channels with available substitutes.
  4047. @end menu
  4048. @node Specifying Additional Channels
  4049. @section Specifying Additional Channels
  4050. @cindex extending the package collection (channels)
  4051. @cindex variant packages (channels)
  4052. You can specify @emph{additional channels} to pull from. To use a channel, write
  4053. @code{~/.config/guix/channels.scm} to instruct @command{guix pull} to pull from it
  4054. @emph{in addition} to the default Guix channel(s):
  4055. @vindex %default-channels
  4056. @lisp
  4057. ;; Add variant packages to those Guix provides.
  4058. (cons (channel
  4059. (name 'variant-packages)
  4060. (url "https://example.org/variant-packages.git"))
  4061. %default-channels)
  4062. @end lisp
  4063. @noindent
  4064. Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
  4065. add a channel the list of channels that the variable @code{%default-channels}
  4066. is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
  4067. Manual}). With this file in place, @command{guix pull} builds not only Guix
  4068. but also the package modules from your own repository. The result in
  4069. @file{~/.config/guix/current} is the union of Guix with your own package
  4070. modules:
  4071. @example
  4072. $ guix pull --list-generations
  4073. @dots{}
  4074. Generation 19 Aug 27 2018 16:20:48
  4075. guix d894ab8
  4076. repository URL: https://git.savannah.gnu.org/git/guix.git
  4077. branch: master
  4078. commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
  4079. variant-packages dd3df5e
  4080. repository URL: https://example.org/variant-packages.git
  4081. branch: master
  4082. commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
  4083. 11 new packages: variant-gimp, variant-emacs-with-cool-features, @dots{}
  4084. 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
  4085. @end example
  4086. @noindent
  4087. The output of @command{guix pull} above shows that Generation@tie{}19 includes
  4088. both Guix and packages from the @code{variant-personal-packages} channel. Among
  4089. the new and upgraded packages that are listed, some like @code{variant-gimp} and
  4090. @code{variant-emacs-with-cool-features} might come from
  4091. @code{variant-packages}, while others come from the Guix default channel.
  4092. @node Using a Custom Guix Channel
  4093. @section Using a Custom Guix Channel
  4094. The channel called @code{guix} specifies where Guix itself---its command-line
  4095. tools as well as its package collection---should be downloaded. For instance,
  4096. suppose you want to update from another copy of the Guix repository at
  4097. @code{example.org}, and specifically the @code{super-hacks} branch, you can
  4098. write in @code{~/.config/guix/channels.scm} this specification:
  4099. @lisp
  4100. ;; Tell 'guix pull' to use another repo.
  4101. (list (channel
  4102. (name 'guix)
  4103. (url "https://example.org/another-guix.git")
  4104. (branch "super-hacks")))
  4105. @end lisp
  4106. @noindent
  4107. From there on, @command{guix pull} will fetch code from the @code{super-hacks}
  4108. branch of the repository at @code{example.org}. The authentication concern is
  4109. addressed below ((@pxref{Channel Authentication}).
  4110. @node Replicating Guix
  4111. @section Replicating Guix
  4112. @cindex pinning, channels
  4113. @cindex replicating Guix
  4114. @cindex reproducibility, of Guix
  4115. The @command{guix pull --list-generations} output above shows precisely which
  4116. commits were used to build this instance of Guix. We can thus replicate it,
  4117. say, on another machine, by providing a channel specification in
  4118. @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
  4119. @lisp
  4120. ;; Deploy specific commits of my channels of interest.
  4121. (list (channel
  4122. (name 'guix)
  4123. (url "https://git.savannah.gnu.org/git/guix.git")
  4124. (commit "6298c3ffd9654d3231a6f25390b056483e8f407c"))
  4125. (channel
  4126. (name 'variant-packages)
  4127. (url "https://example.org/variant-packages.git")
  4128. (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
  4129. @end lisp
  4130. The @command{guix describe --format=channels} command can even generate this
  4131. list of channels directly (@pxref{Invoking guix describe}). The resulting
  4132. file can be used with the -C options of @command{guix pull}
  4133. (@pxref{Invoking guix pull}) or @command{guix time-machine}
  4134. (@pxref{Invoking guix time-machine}).
  4135. At this point the two machines run the @emph{exact same Guix}, with access to
  4136. the @emph{exact same packages}. The output of @command{guix build gimp} on
  4137. one machine will be exactly the same, bit for bit, as the output of the same
  4138. command on the other machine. It also means both machines have access to all
  4139. the source code of Guix and, transitively, to all the source code of every
  4140. package it defines.
  4141. This gives you super powers, allowing you to track the provenance of binary
  4142. artifacts with very fine grain, and to reproduce software environments at
  4143. will---some sort of ``meta reproducibility'' capabilities, if you will.
  4144. @xref{Inferiors}, for another way to take advantage of these super powers.
  4145. @node Channel Authentication
  4146. @section Channel Authentication
  4147. @anchor{channel-authentication}
  4148. @cindex authentication, of channel code
  4149. The @command{guix pull} and @command{guix time-machine} commands
  4150. @dfn{authenticate} the code retrieved from channels: they make sure each
  4151. commit that is fetched is signed by an authorized developer. The goal
  4152. is to protect from unauthorized modifications to the channel that would
  4153. lead users to run malicious code.
  4154. As a user, you must provide a @dfn{channel introduction} in your
  4155. channels file so that Guix knows how to authenticate its first commit.
  4156. A channel specification, including its introduction, looks something
  4157. along these lines:
  4158. @lisp
  4159. (channel
  4160. (name 'some-channel)
  4161. (url "https://example.org/some-channel.git")
  4162. (introduction
  4163. (make-channel-introduction
  4164. "6f0d8cc0d88abb59c324b2990bfee2876016bb86"
  4165. (openpgp-fingerprint
  4166. "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
  4167. @end lisp
  4168. The specification above shows the name and URL of the channel. The call
  4169. to @code{make-channel-introduction} above specifies that authentication
  4170. of this channel starts at commit @code{6f0d8cc@dots{}}, which is signed
  4171. by the OpenPGP key with fingerprint @code{CABB A931@dots{}}.
  4172. For the main channel, called @code{guix}, you automatically get that
  4173. information from your Guix installation. For other channels, include
  4174. the channel introduction provided by the channel authors in your
  4175. @file{channels.scm} file. Make sure you retrieve the channel
  4176. introduction from a trusted source since that is the root of your trust.
  4177. If you're curious about the authentication mechanics, read on!
  4178. @node Creating a Channel
  4179. @section Creating a Channel
  4180. @cindex personal packages (channels)
  4181. @cindex channels, for personal packages
  4182. Let's say you have a bunch of custom package variants or personal packages
  4183. that you think would make little sense to contribute to the Guix project, but
  4184. would like to have these packages transparently available to you at the
  4185. command line. You would first write modules containing those package
  4186. definitions (@pxref{Package Modules}), maintain them in a Git repository, and
  4187. then you and anyone else can use it as an additional channel to get packages
  4188. from. Neat, no?
  4189. @c What follows stems from discussions at
  4190. @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
  4191. @c earlier discussions on guix-devel@gnu.org.
  4192. @quotation Warning
  4193. Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
  4194. publish your personal channel to the world, we would like to share a few words
  4195. of caution:
  4196. @itemize
  4197. @item
  4198. Before publishing a channel, please consider contributing your package
  4199. definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
  4200. to free software of all sorts, and packages in Guix proper are readily
  4201. available to all Guix users and benefit from the project's quality assurance
  4202. process.
  4203. @item
  4204. When you maintain package definitions outside Guix, we, Guix developers,
  4205. consider that @emph{the compatibility burden is on you}. Remember that
  4206. package modules and package definitions are just Scheme code that uses various
  4207. programming interfaces (APIs). We want to remain free to change these APIs to
  4208. keep improving Guix, possibly in ways that break your channel. We never
  4209. change APIs gratuitously, but we will @emph{not} commit to freezing APIs
  4210. either.
  4211. @item
  4212. Corollary: if you're using an external channel and that channel breaks, please
  4213. @emph{report the issue to the channel authors}, not to the Guix project.
  4214. @end itemize
  4215. You've been warned! Having said this, we believe external channels are a
  4216. practical way to exert your freedom to augment Guix' package collection and to
  4217. share your improvements, which are basic tenets of
  4218. @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
  4219. email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
  4220. @end quotation
  4221. To create a channel, create a Git repository containing your own package
  4222. modules and make it available. The repository can contain anything, but a
  4223. useful channel will contain Guile modules that export packages. Once you
  4224. start using a channel, Guix will behave as if the root directory of that
  4225. channel's Git repository has been added to the Guile load path (@pxref{Load
  4226. Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
  4227. contains a file at @file{my-packages/my-tools.scm} that defines a Guile
  4228. module, then the module will be available under the name @code{(my-packages
  4229. my-tools)}, and you will be able to use it like any other module
  4230. (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
  4231. As a channel author, consider bundling authentication material with your
  4232. channel so that users can authenticate it. @xref{Channel
  4233. Authentication}, and @ref{Specifying Channel Authorizations}, for info
  4234. on how to do it.
  4235. @node Package Modules in a Sub-directory
  4236. @section Package Modules in a Sub-directory
  4237. @cindex subdirectory, channels
  4238. As a channel author, you may want to keep your channel modules in a
  4239. sub-directory. If your modules are in the sub-directory @file{guix}, you must
  4240. add a meta-data file @file{.guix-channel} that contains:
  4241. @lisp
  4242. (channel
  4243. (version 0)
  4244. (directory "guix"))
  4245. @end lisp
  4246. @node Declaring Channel Dependencies
  4247. @section Declaring Channel Dependencies
  4248. @cindex dependencies, channels
  4249. @cindex meta-data, channels
  4250. Channel authors may decide to augment a package collection provided by other
  4251. channels. They can declare their channel to be dependent on other channels in
  4252. a meta-data file @file{.guix-channel}, which is to be placed in the root of
  4253. the channel repository.
  4254. The meta-data file should contain a simple S-expression like this:
  4255. @lisp
  4256. (channel
  4257. (version 0)
  4258. (dependencies
  4259. (channel
  4260. (name some-collection)
  4261. (url "https://example.org/first-collection.git")
  4262. ;; The 'introduction' bit below is optional: you would
  4263. ;; provide it for dependencies that can be authenticated.
  4264. (introduction
  4265. (channel-introduction
  4266. (version 0)
  4267. (commit "a8883b58dc82e167c96506cf05095f37c2c2c6cd")
  4268. (signer "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
  4269. (channel
  4270. (name some-other-collection)
  4271. (url "https://example.org/second-collection.git")
  4272. (branch "testing"))))
  4273. @end lisp
  4274. In the above example this channel is declared to depend on two other channels,
  4275. which will both be fetched automatically. The modules provided by the channel
  4276. will be compiled in an environment where the modules of all these declared
  4277. channels are available.
  4278. For the sake of reliability and maintainability, you should avoid dependencies
  4279. on channels that you don't control, and you should aim to keep the number of
  4280. dependencies to a minimum.
  4281. @node Specifying Channel Authorizations
  4282. @section Specifying Channel Authorizations
  4283. @cindex channel authorizations
  4284. @anchor{channel-authorizations}
  4285. As we saw above, Guix ensures the source code it pulls from channels
  4286. comes from authorized developers. As a channel author, you need to
  4287. specify the list of authorized developers in the
  4288. @file{.guix-authorizations} file in the channel's Git repository. The
  4289. authentication rule is simple: each commit must be signed by a key
  4290. listed in the @file{.guix-authorizations} file of its parent
  4291. commit(s)@footnote{Git commits form a @dfn{directed acyclic graph}
  4292. (DAG). Each commit can have zero or more parents; ``regular'' commits
  4293. have one parent and merge commits have two parent commits. Read
  4294. @uref{https://eagain.net/articles/git-for-computer-scientists/, @i{Git
  4295. for Computer Scientists}} for a great overview.} The
  4296. @file{.guix-authorizations} file looks like this:
  4297. @lisp
  4298. ;; Example '.guix-authorizations' file.
  4299. (authorizations
  4300. (version 0) ;current file format version
  4301. (("AD17 A21E F8AE D8F1 CC02 DBD9 F8AE D8F1 765C 61E3"
  4302. (name "alice"))
  4303. ("2A39 3FFF 68F4 EF7A 3D29 12AF 68F4 EF7A 22FB B2D5"
  4304. (name "bob"))
  4305. ("CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"
  4306. (name "charlie"))))
  4307. @end lisp
  4308. Each fingerprint is followed by optional key/value pairs, as in the
  4309. example above. Currently these key/value pairs are ignored.
  4310. This authentication rule creates a chicken-and-egg issue: how do we
  4311. authenticate the first commit? Related to that: how do we deal with
  4312. channels whose repository history contains unsigned commits and lack
  4313. @file{.guix-authorizations}? And how do we fork existing channels?
  4314. @cindex channel introduction
  4315. Channel introductions answer these questions by describing the first
  4316. commit of a channel that should be authenticated. The first time a
  4317. channel is fetched with @command{guix pull} or @command{guix
  4318. time-machine}, the command looks up the introductory commit and verifies
  4319. that it is signed by the specified OpenPGP key. From then on, it
  4320. authenticates commits according to the rule above.
  4321. Additionally, your channel must provide all the OpenPGP keys that were
  4322. ever mentioned in @file{.guix-authorizations}, stored as @file{.key}
  4323. files, which can be either binary or ``ASCII-armored''. By default,
  4324. those @file{.key} files are searched for in the branch named
  4325. @code{keyring} but you can specify a different branch name in
  4326. @code{.guix-channel} like so:
  4327. @lisp
  4328. (channel
  4329. (version 0)
  4330. (keyring-reference "my-keyring-branch"))
  4331. @end lisp
  4332. To summarize, as the author of a channel, there are three things you have
  4333. to do to allow users to authenticate your code:
  4334. @enumerate
  4335. @item
  4336. Export the OpenPGP keys of past and present committers with @command{gpg
  4337. --export} and store them in @file{.key} files, by default in a branch
  4338. named @code{keyring} (we recommend making it an @dfn{orphan branch}).
  4339. @item
  4340. Introduce an initial @file{.guix-authorizations} in the channel's
  4341. repository. Do that in a signed commit (@pxref{Commit Access}, for
  4342. information on how to sign Git commits.)
  4343. @item
  4344. Advertise the channel introduction, for instance on your channel's web
  4345. page. The channel introduction, as we saw above, is the commit/key
  4346. pair---i.e., the commit that introduced @file{.guix-authorizations}, and
  4347. the fingerprint of the OpenPGP used to sign it.
  4348. @end enumerate
  4349. Before pushing to your public Git repository, you can run @command{guix
  4350. git-authenticate} to verify that you did sign all the commits you are
  4351. about to push with an authorized key:
  4352. @example
  4353. guix git authenticate @var{commit} @var{signer}
  4354. @end example
  4355. @noindent
  4356. where @var{commit} and @var{signer} are your channel introduction.
  4357. @xref{Invoking guix git authenticate}, for details.
  4358. Publishing a signed channel requires discipline: any mistake, such as an
  4359. unsigned commit or a commit signed by an unauthorized key, will prevent
  4360. users from pulling from your channel---well, that's the whole point of
  4361. authentication! Pay attention to merges in particular: merge commits
  4362. are considered authentic if and only if they are signed by a key present
  4363. in the @file{.guix-authorizations} file of @emph{both} branches.
  4364. @node Primary URL
  4365. @section Primary URL
  4366. @cindex primary URL, channels
  4367. Channel authors can indicate the primary URL of their channel's Git
  4368. repository in the @file{.guix-channel} file, like so:
  4369. @lisp
  4370. (channel
  4371. (version 0)
  4372. (url "https://example.org/guix.git"))
  4373. @end lisp
  4374. This allows @command{guix pull} to determine whether it is pulling code
  4375. from a mirror of the channel; when that is the case, it warns the user
  4376. that the mirror might be stale and displays the primary URL@. That way,
  4377. users cannot be tricked into fetching code from a stale mirror that does
  4378. not receive security updates.
  4379. This feature only makes sense for authenticated repositories, such as
  4380. the official @code{guix} channel, for which @command{guix pull} ensures
  4381. the code it fetches is authentic.
  4382. @node Writing Channel News
  4383. @section Writing Channel News
  4384. @cindex news, for channels
  4385. Channel authors may occasionally want to communicate to their users
  4386. information about important changes in the channel. You'd send them all
  4387. an email, but that's not convenient.
  4388. Instead, channels can provide a @dfn{news file}; when the channel users
  4389. run @command{guix pull}, that news file is automatically read and
  4390. @command{guix pull --news} can display the announcements that correspond
  4391. to the new commits that have been pulled, if any.
  4392. To do that, channel authors must first declare the name of the news file
  4393. in their @file{.guix-channel} file:
  4394. @lisp
  4395. (channel
  4396. (version 0)
  4397. (news-file "etc/news.txt"))
  4398. @end lisp
  4399. The news file itself, @file{etc/news.txt} in this example, must look
  4400. something like this:
  4401. @lisp
  4402. (channel-news
  4403. (version 0)
  4404. (entry (tag "the-bug-fix")
  4405. (title (en "Fixed terrible bug")
  4406. (fr "Oh la la"))
  4407. (body (en "@@emph@{Good news@}! It's fixed!")
  4408. (eo "Certe ĝi pli bone funkcias nun!")))
  4409. (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
  4410. (title (en "Added a great package")
  4411. (ca "Què vol dir guix?"))
  4412. (body (en "Don't miss the @@code@{hello@} package!"))))
  4413. @end lisp
  4414. While the news file is using the Scheme syntax, avoid naming it with a
  4415. @file{.scm} extension or else it will get picked up when building the
  4416. channel and yield an error since it is not a valid module.
  4417. Alternatively, you can move the channel module to a subdirectory and
  4418. store the news file in another directory.
  4419. The file consists of a list of @dfn{news entries}. Each entry is
  4420. associated with a commit or tag: it describes changes made in this
  4421. commit, possibly in preceding commits as well. Users see entries only
  4422. the first time they obtain the commit the entry refers to.
  4423. The @code{title} field should be a one-line summary while @code{body}
  4424. can be arbitrarily long, and both can contain Texinfo markup
  4425. (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
  4426. a list of language tag/message tuples, which allows @command{guix pull}
  4427. to display news in the language that corresponds to the user's locale.
  4428. If you want to translate news using a gettext-based workflow, you can
  4429. extract translatable strings with @command{xgettext} (@pxref{xgettext
  4430. Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
  4431. you write news entries in English first, the command below creates a PO
  4432. file containing the strings to translate:
  4433. @example
  4434. xgettext -o news.po -l scheme -ken etc/news.txt
  4435. @end example
  4436. To sum up, yes, you could use your channel as a blog. But beware, this
  4437. is @emph{not quite} what your users might expect.
  4438. @node Channels with Substitutes
  4439. @section Channels with Substitutes
  4440. When running @command{guix pull}, Guix will first compile the
  4441. definitions of every available package. This is an expensive operation
  4442. for which substitutes (@pxref{Substitutes}) may be available. The
  4443. following snippet in @file{channels.scm} will ensure that @command{guix
  4444. pull} uses the latest commit with available substitutes for the package
  4445. definitions: this is done by querying the continuous integration
  4446. server at @url{https://ci.guix.gnu.org}.
  4447. @lisp
  4448. (use-modules (guix ci))
  4449. (list (channel-with-substitutes-available
  4450. %default-guix-channel
  4451. "https://ci.guix.gnu.org"))
  4452. @end lisp
  4453. Note that this does not mean that all the packages that you will
  4454. install after running @command{guix pull} will have available
  4455. substitutes. It only ensures that @command{guix pull} will not try to
  4456. compile package definitions. This is particularly useful when using
  4457. machines with limited resources.
  4458. @c *********************************************************************
  4459. @node Development
  4460. @chapter Development
  4461. @cindex software development
  4462. If you are a software developer, Guix provides tools that you should find
  4463. helpful---independently of the language you're developing in. This is what
  4464. this chapter is about.
  4465. The @command{guix environment} command provides a convenient way to set up
  4466. @dfn{development environments} containing all the dependencies and tools
  4467. necessary to work on the software package of your choice. The @command{guix
  4468. pack} command allows you to create @dfn{application bundles} that can be
  4469. easily distributed to users who do not run Guix.
  4470. @menu
  4471. * Invoking guix environment:: Setting up development environments.
  4472. * Invoking guix pack:: Creating software bundles.
  4473. * The GCC toolchain:: Working with languages supported by GCC.
  4474. * Invoking guix git authenticate:: Authenticating Git repositories.
  4475. @end menu
  4476. @node Invoking guix environment
  4477. @section Invoking @command{guix environment}
  4478. @cindex reproducible build environments
  4479. @cindex development environments
  4480. @cindex @command{guix environment}
  4481. @cindex environment, package build environment
  4482. The purpose of @command{guix environment} is to assist hackers in
  4483. creating reproducible development environments without polluting their
  4484. package profile. The @command{guix environment} tool takes one or more
  4485. packages, builds all of their inputs, and creates a shell
  4486. environment to use them.
  4487. The general syntax is:
  4488. @example
  4489. guix environment @var{options} @var{package}@dots{}
  4490. @end example
  4491. The following example spawns a new shell set up for the development of
  4492. GNU@tie{}Guile:
  4493. @example
  4494. guix environment guile
  4495. @end example
  4496. If the needed dependencies are not built yet, @command{guix environment}
  4497. automatically builds them. The environment of the new shell is an
  4498. augmented version of the environment that @command{guix environment} was
  4499. run in. It contains the necessary search paths for building the given
  4500. package added to the existing environment variables. To create
  4501. a ``pure'' environment, in which the original environment variables have
  4502. been unset, use the @option{--pure} option@footnote{Users sometimes
  4503. wrongfully augment environment variables such as @env{PATH} in their
  4504. @file{~/.bashrc} file. As a consequence, when @command{guix
  4505. environment} launches it, Bash may read @file{~/.bashrc}, thereby
  4506. introducing ``impurities'' in these environment variables. It is an
  4507. error to define such environment variables in @file{.bashrc}; instead,
  4508. they should be defined in @file{.bash_profile}, which is sourced only by
  4509. log-in shells. @xref{Bash Startup Files,,, bash, The GNU Bash Reference
  4510. Manual}, for details on Bash start-up files.}.
  4511. Exiting from a Guix environment is the same as exiting from the shell,
  4512. and will place the user back in the old environment before @command{guix
  4513. environment} was invoked. The next garbage collection (@pxref{Invoking
  4514. guix gc}) will clean up packages that were installed from within the
  4515. environment and are no longer used outside of it.
  4516. @vindex GUIX_ENVIRONMENT
  4517. @command{guix environment} defines the @env{GUIX_ENVIRONMENT}
  4518. variable in the shell it spawns; its value is the file name of the
  4519. profile of this environment. This allows users to, say, define a
  4520. specific prompt for development environments in their @file{.bashrc}
  4521. (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
  4522. @example
  4523. if [ -n "$GUIX_ENVIRONMENT" ]
  4524. then
  4525. export PS1="\u@@\h \w [dev]\$ "
  4526. fi
  4527. @end example
  4528. @noindent
  4529. ...@: or to browse the profile:
  4530. @example
  4531. $ ls "$GUIX_ENVIRONMENT/bin"
  4532. @end example
  4533. Additionally, more than one package may be specified, in which case the
  4534. union of the inputs for the given packages are used. For example, the
  4535. command below spawns a shell where all of the dependencies of both Guile
  4536. and Emacs are available:
  4537. @example
  4538. guix environment guile emacs
  4539. @end example
  4540. Sometimes an interactive shell session is not desired. An arbitrary
  4541. command may be invoked by placing the @code{--} token to separate the
  4542. command from the rest of the arguments:
  4543. @example
  4544. guix environment guile -- make -j4
  4545. @end example
  4546. In other situations, it is more convenient to specify the list of
  4547. packages needed in the environment. For example, the following command
  4548. runs @command{python} from an environment containing Python@tie{}2.7 and
  4549. NumPy:
  4550. @example
  4551. guix environment --ad-hoc python2-numpy python-2.7 -- python
  4552. @end example
  4553. Furthermore, one might want the dependencies of a package and also some
  4554. additional packages that are not build-time or runtime dependencies, but
  4555. are useful when developing nonetheless. Because of this, the
  4556. @option{--ad-hoc} flag is positional. Packages appearing before
  4557. @option{--ad-hoc} are interpreted as packages whose dependencies will be
  4558. added to the environment. Packages appearing after are interpreted as
  4559. packages that will be added to the environment directly. For example,
  4560. the following command creates a Guix development environment that
  4561. additionally includes Git and strace:
  4562. @example
  4563. guix environment --pure guix --ad-hoc git strace
  4564. @end example
  4565. @cindex container
  4566. Sometimes it is desirable to isolate the environment as much as
  4567. possible, for maximal purity and reproducibility. In particular, when
  4568. using Guix on a host distro that is not Guix System, it is desirable to
  4569. prevent access to @file{/usr/bin} and other system-wide resources from
  4570. the development environment. For example, the following command spawns
  4571. a Guile REPL in a ``container'' where only the store and the current
  4572. working directory are mounted:
  4573. @example
  4574. guix environment --ad-hoc --container guile -- guile
  4575. @end example
  4576. @quotation Note
  4577. The @option{--container} option requires Linux-libre 3.19 or newer.
  4578. @end quotation
  4579. @cindex certificates
  4580. Another typical use case for containers is to run security-sensitive
  4581. applications such as a web browser. To run Eolie, we must expose and
  4582. share some files and directories; we include @code{nss-certs} and expose
  4583. @file{/etc/ssl/certs/} for HTTPS authentication; finally we preserve the
  4584. @env{DISPLAY} environment variable since containerized graphical
  4585. applications won't display without it.
  4586. @example
  4587. guix environment --preserve='^DISPLAY$' --container --network \
  4588. --expose=/etc/machine-id \
  4589. --expose=/etc/ssl/certs/ \
  4590. --share=$HOME/.local/share/eolie/=$HOME/.local/share/eolie/ \
  4591. --ad-hoc eolie nss-certs dbus -- eolie
  4592. @end example
  4593. The available options are summarized below.
  4594. @table @code
  4595. @item --root=@var{file}
  4596. @itemx -r @var{file}
  4597. @cindex persistent environment
  4598. @cindex garbage collector root, for environments
  4599. Make @var{file} a symlink to the profile for this environment, and
  4600. register it as a garbage collector root.
  4601. This is useful if you want to protect your environment from garbage
  4602. collection, to make it ``persistent''.
  4603. When this option is omitted, the environment is protected from garbage
  4604. collection only for the duration of the @command{guix environment}
  4605. session. This means that next time you recreate the same environment,
  4606. you could have to rebuild or re-download packages. @xref{Invoking guix
  4607. gc}, for more on GC roots.
  4608. @item --expression=@var{expr}
  4609. @itemx -e @var{expr}
  4610. Create an environment for the package or list of packages that
  4611. @var{expr} evaluates to.
  4612. For example, running:
  4613. @example
  4614. guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
  4615. @end example
  4616. starts a shell with the environment for this specific variant of the
  4617. PETSc package.
  4618. Running:
  4619. @example
  4620. guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
  4621. @end example
  4622. starts a shell with all the base system packages available.
  4623. The above commands only use the default output of the given packages.
  4624. To select other outputs, two element tuples can be specified:
  4625. @example
  4626. guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
  4627. @end example
  4628. @item --load=@var{file}
  4629. @itemx -l @var{file}
  4630. Create an environment for the package or list of packages that the code
  4631. within @var{file} evaluates to.
  4632. As an example, @var{file} might contain a definition like this
  4633. (@pxref{Defining Packages}):
  4634. @lisp
  4635. @verbatiminclude environment-gdb.scm
  4636. @end lisp
  4637. @item --manifest=@var{file}
  4638. @itemx -m @var{file}
  4639. Create an environment for the packages contained in the manifest object
  4640. returned by the Scheme code in @var{file}. This option can be repeated
  4641. several times, in which case the manifests are concatenated.
  4642. This is similar to the same-named option in @command{guix package}
  4643. (@pxref{profile-manifest, @option{--manifest}}) and uses the same
  4644. manifest files.
  4645. @item --ad-hoc
  4646. Include all specified packages in the resulting environment, as if an
  4647. @i{ad hoc} package were defined with them as inputs. This option is
  4648. useful for quickly creating an environment without having to write a
  4649. package expression to contain the desired inputs.
  4650. For instance, the command:
  4651. @example
  4652. guix environment --ad-hoc guile guile-sdl -- guile
  4653. @end example
  4654. runs @command{guile} in an environment where Guile and Guile-SDL are
  4655. available.
  4656. Note that this example implicitly asks for the default output of
  4657. @code{guile} and @code{guile-sdl}, but it is possible to ask for a
  4658. specific output---e.g., @code{glib:bin} asks for the @code{bin} output
  4659. of @code{glib} (@pxref{Packages with Multiple Outputs}).
  4660. This option may be composed with the default behavior of @command{guix
  4661. environment}. Packages appearing before @option{--ad-hoc} are
  4662. interpreted as packages whose dependencies will be added to the
  4663. environment, the default behavior. Packages appearing after are
  4664. interpreted as packages that will be added to the environment directly.
  4665. @item --pure
  4666. Unset existing environment variables when building the new environment, except
  4667. those specified with @option{--preserve} (see below). This has the effect of
  4668. creating an environment in which search paths only contain package inputs.
  4669. @item --preserve=@var{regexp}
  4670. @itemx -E @var{regexp}
  4671. When used alongside @option{--pure}, preserve the environment variables
  4672. matching @var{regexp}---in other words, put them on a ``white list'' of
  4673. environment variables that must be preserved. This option can be repeated
  4674. several times.
  4675. @example
  4676. guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
  4677. -- mpirun @dots{}
  4678. @end example
  4679. This example runs @command{mpirun} in a context where the only environment
  4680. variables defined are @env{PATH}, environment variables whose name starts
  4681. with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
  4682. @env{USER}, etc.).
  4683. @item --search-paths
  4684. Display the environment variable definitions that make up the
  4685. environment.
  4686. @item --system=@var{system}
  4687. @itemx -s @var{system}
  4688. Attempt to build for @var{system}---e.g., @code{i686-linux}.
  4689. @item --container
  4690. @itemx -C
  4691. @cindex container
  4692. Run @var{command} within an isolated container. The current working
  4693. directory outside the container is mapped inside the container.
  4694. Additionally, unless overridden with @option{--user}, a dummy home
  4695. directory is created that matches the current user's home directory, and
  4696. @file{/etc/passwd} is configured accordingly.
  4697. The spawned process runs as the current user outside the container. Inside
  4698. the container, it has the same UID and GID as the current user, unless
  4699. @option{--user} is passed (see below).
  4700. @item --network
  4701. @itemx -N
  4702. For containers, share the network namespace with the host system.
  4703. Containers created without this flag only have access to the loopback
  4704. device.
  4705. @item --link-profile
  4706. @itemx -P
  4707. For containers, link the environment profile to @file{~/.guix-profile}
  4708. within the container and set @code{GUIX_ENVIRONMENT} to that.
  4709. This is equivalent to making @file{~/.guix-profile} a symlink to the
  4710. actual profile within the container.
  4711. Linking will fail and abort the environment if the directory already
  4712. exists, which will certainly be the case if @command{guix environment}
  4713. was invoked in the user's home directory.
  4714. Certain packages are configured to look in @file{~/.guix-profile} for
  4715. configuration files and data;@footnote{For example, the
  4716. @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
  4717. for additional fonts.} @option{--link-profile} allows these programs to
  4718. behave as expected within the environment.
  4719. @item --user=@var{user}
  4720. @itemx -u @var{user}
  4721. For containers, use the username @var{user} in place of the current
  4722. user. The generated @file{/etc/passwd} entry within the container will
  4723. contain the name @var{user}, the home directory will be
  4724. @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
  4725. the UID and GID inside the container are 1000. @var{user}
  4726. need not exist on the system.
  4727. Additionally, any shared or exposed path (see @option{--share} and
  4728. @option{--expose} respectively) whose target is within the current user's
  4729. home directory will be remapped relative to @file{/home/USER}; this
  4730. includes the automatic mapping of the current working directory.
  4731. @example
  4732. # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
  4733. cd $HOME/wd
  4734. guix environment --container --user=foo \
  4735. --expose=$HOME/test \
  4736. --expose=/tmp/target=$HOME/target
  4737. @end example
  4738. While this will limit the leaking of user identity through home paths
  4739. and each of the user fields, this is only one useful component of a
  4740. broader privacy/anonymity solution---not one in and of itself.
  4741. @item --no-cwd
  4742. For containers, the default behavior is to share the current working
  4743. directory with the isolated container and immediately change to that
  4744. directory within the container. If this is undesirable,
  4745. @option{--no-cwd} will cause the current working directory to @emph{not}
  4746. be automatically shared and will change to the user's home directory
  4747. within the container instead. See also @option{--user}.
  4748. @item --expose=@var{source}[=@var{target}]
  4749. @itemx --share=@var{source}[=@var{target}]
  4750. For containers, @option{--expose} (resp. @option{--share}) exposes the
  4751. file system @var{source} from the host system as the read-only
  4752. (resp. writable) file system @var{target} within the container. If
  4753. @var{target} is not specified, @var{source} is used as the target mount
  4754. point in the container.
  4755. The example below spawns a Guile REPL in a container in which the user's
  4756. home directory is accessible read-only via the @file{/exchange}
  4757. directory:
  4758. @example
  4759. guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
  4760. @end example
  4761. @end table
  4762. @command{guix environment}
  4763. also supports all of the common build options that @command{guix
  4764. build} supports (@pxref{Common Build Options}) as well as package
  4765. transformation options (@pxref{Package Transformation Options}).
  4766. @node Invoking guix pack
  4767. @section Invoking @command{guix pack}
  4768. Occasionally you want to pass software to people who are not (yet!)
  4769. lucky enough to be using Guix. You'd tell them to run @command{guix
  4770. package -i @var{something}}, but that's not possible in this case. This
  4771. is where @command{guix pack} comes in.
  4772. @quotation Note
  4773. If you are looking for ways to exchange binaries among machines that
  4774. already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
  4775. publish}, and @ref{Invoking guix archive}.
  4776. @end quotation
  4777. @cindex pack
  4778. @cindex bundle
  4779. @cindex application bundle
  4780. @cindex software bundle
  4781. The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
  4782. @dfn{software bundle}: it creates a tarball or some other archive
  4783. containing the binaries of the software you're interested in, and all
  4784. its dependencies. The resulting archive can be used on any machine that
  4785. does not have Guix, and people can run the exact same binaries as those
  4786. you have with Guix. The pack itself is created in a bit-reproducible
  4787. fashion, so anyone can verify that it really contains the build results
  4788. that you pretend to be shipping.
  4789. For example, to create a bundle containing Guile, Emacs, Geiser, and all
  4790. their dependencies, you can run:
  4791. @example
  4792. $ guix pack guile emacs geiser
  4793. @dots{}
  4794. /gnu/store/@dots{}-pack.tar.gz
  4795. @end example
  4796. The result here is a tarball containing a @file{/gnu/store} directory
  4797. with all the relevant packages. The resulting tarball contains a
  4798. @dfn{profile} with the three packages of interest; the profile is the
  4799. same as would be created by @command{guix package -i}. It is this
  4800. mechanism that is used to create Guix's own standalone binary tarball
  4801. (@pxref{Binary Installation}).
  4802. Users of this pack would have to run
  4803. @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
  4804. find inconvenient. To work around it, you can create, say, a
  4805. @file{/opt/gnu/bin} symlink to the profile:
  4806. @example
  4807. guix pack -S /opt/gnu/bin=bin guile emacs geiser
  4808. @end example
  4809. @noindent
  4810. That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
  4811. @cindex relocatable binaries, with @command{guix pack}
  4812. What if the recipient of your pack does not have root privileges on
  4813. their machine, and thus cannot unpack it in the root file system? In
  4814. that case, you will want to use the @option{--relocatable} option (see
  4815. below). This option produces @dfn{relocatable binaries}, meaning they
  4816. they can be placed anywhere in the file system hierarchy: in the example
  4817. above, users can unpack your tarball in their home directory and
  4818. directly run @file{./opt/gnu/bin/guile}.
  4819. @cindex Docker, build an image with guix pack
  4820. Alternatively, you can produce a pack in the Docker image format using
  4821. the following command:
  4822. @example
  4823. guix pack -f docker -S /bin=bin guile guile-readline
  4824. @end example
  4825. @noindent
  4826. The result is a tarball that can be passed to the @command{docker load}
  4827. command, followed by @code{docker run}:
  4828. @example
  4829. docker load < @var{file}
  4830. docker run -ti guile-guile-readline /bin/guile
  4831. @end example
  4832. @noindent
  4833. where @var{file} is the image returned by @var{guix pack}, and
  4834. @code{guile-guile-readline} is its ``image tag''. See the
  4835. @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
  4836. documentation} for more information.
  4837. @cindex Singularity, build an image with guix pack
  4838. @cindex SquashFS, build an image with guix pack
  4839. Yet another option is to produce a SquashFS image with the following
  4840. command:
  4841. @example
  4842. guix pack -f squashfs bash guile emacs geiser
  4843. @end example
  4844. @noindent
  4845. The result is a SquashFS file system image that can either be mounted or
  4846. directly be used as a file system container image with the
  4847. @uref{https://www.sylabs.io/docs/, Singularity container execution
  4848. environment}, using commands like @command{singularity shell} or
  4849. @command{singularity exec}.
  4850. Several command-line options allow you to customize your pack:
  4851. @table @code
  4852. @item --format=@var{format}
  4853. @itemx -f @var{format}
  4854. Produce a pack in the given @var{format}.
  4855. The available formats are:
  4856. @table @code
  4857. @item tarball
  4858. This is the default format. It produces a tarball containing all the
  4859. specified binaries and symlinks.
  4860. @item docker
  4861. This produces a tarball that follows the
  4862. @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
  4863. Docker Image Specification}. The ``repository name'' as it appears in
  4864. the output of the @command{docker images} command is computed from
  4865. package names passed on the command line or in the manifest file.
  4866. @item squashfs
  4867. This produces a SquashFS image containing all the specified binaries and
  4868. symlinks, as well as empty mount points for virtual file systems like
  4869. procfs.
  4870. @quotation Note
  4871. Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
  4872. For that reason, @command{guix pack -f squashfs} always implies @code{-S
  4873. /bin=bin}. Thus, your @command{guix pack} invocation must always start
  4874. with something like:
  4875. @example
  4876. guix pack -f squashfs bash @dots{}
  4877. @end example
  4878. If you forget the @code{bash} (or similar) package, @command{singularity
  4879. run} and @command{singularity exec} will fail with an unhelpful ``no
  4880. such file or directory'' message.
  4881. @end quotation
  4882. @end table
  4883. @cindex relocatable binaries
  4884. @item --relocatable
  4885. @itemx -R
  4886. Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
  4887. anywhere in the file system hierarchy and run from there.
  4888. When this option is passed once, the resulting binaries require support for
  4889. @dfn{user namespaces} in the kernel Linux; when passed
  4890. @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
  4891. PRoot support, can be thought of as the abbreviation of ``Really
  4892. Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to
  4893. other techniques if user namespaces are unavailable, and essentially
  4894. work anywhere---see below for the implications.
  4895. For example, if you create a pack containing Bash with:
  4896. @example
  4897. guix pack -RR -S /mybin=bin bash
  4898. @end example
  4899. @noindent
  4900. ...@: you can copy that pack to a machine that lacks Guix, and from your
  4901. home directory as a normal user, run:
  4902. @example
  4903. tar xf pack.tar.gz
  4904. ./mybin/sh
  4905. @end example
  4906. @noindent
  4907. In that shell, if you type @code{ls /gnu/store}, you'll notice that
  4908. @file{/gnu/store} shows up and contains all the dependencies of
  4909. @code{bash}, even though the machine actually lacks @file{/gnu/store}
  4910. altogether! That is probably the simplest way to deploy Guix-built
  4911. software on a non-Guix machine.
  4912. @quotation Note
  4913. By default, relocatable binaries rely on the @dfn{user namespace} feature of
  4914. the kernel Linux, which allows unprivileged users to mount or change root.
  4915. Old versions of Linux did not support it, and some GNU/Linux distributions
  4916. turn it off.
  4917. To produce relocatable binaries that work even in the absence of user
  4918. namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
  4919. case, binaries will try user namespace support and fall back to another
  4920. @dfn{execution engine} if user namespaces are not supported. The
  4921. following execution engines are supported:
  4922. @table @code
  4923. @item default
  4924. Try user namespaces and fall back to PRoot if user namespaces are not
  4925. supported (see below).
  4926. @item performance
  4927. Try user namespaces and fall back to Fakechroot if user namespaces are
  4928. not supported (see below).
  4929. @item userns
  4930. Run the program through user namespaces and abort if they are not
  4931. supported.
  4932. @item proot
  4933. Run through PRoot. The @uref{https://proot-me.github.io/, PRoot} program
  4934. provides the necessary
  4935. support for file system virtualization. It achieves that by using the
  4936. @code{ptrace} system call on the running program. This approach has the
  4937. advantage to work without requiring special kernel support, but it incurs
  4938. run-time overhead every time a system call is made.
  4939. @item fakechroot
  4940. Run through Fakechroot. @uref{https://github.com/dex4er/fakechroot/,
  4941. Fakechroot} virtualizes file system accesses by intercepting calls to C
  4942. library functions such as @code{open}, @code{stat}, @code{exec}, and so
  4943. on. Unlike PRoot, it incurs very little overhead. However, it does not
  4944. always work: for example, some file system accesses made from within the
  4945. C library are not intercepted, and file system accesses made @i{via}
  4946. direct syscalls are not intercepted either, leading to erratic behavior.
  4947. @end table
  4948. @vindex GUIX_EXECUTION_ENGINE
  4949. When running a wrapped program, you can explicitly request one of the
  4950. execution engines listed above by setting the
  4951. @env{GUIX_EXECUTION_ENGINE} environment variable accordingly.
  4952. @end quotation
  4953. @cindex entry point, for Docker images
  4954. @item --entry-point=@var{command}
  4955. Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
  4956. format supports it---currently @code{docker} and @code{squashfs} (Singularity)
  4957. support it. @var{command} must be relative to the profile contained in the
  4958. pack.
  4959. The entry point specifies the command that tools like @code{docker run} or
  4960. @code{singularity run} automatically start by default. For example, you can
  4961. do:
  4962. @example
  4963. guix pack -f docker --entry-point=bin/guile guile
  4964. @end example
  4965. The resulting pack can easily be loaded and @code{docker run} with no extra
  4966. arguments will spawn @code{bin/guile}:
  4967. @example
  4968. docker load -i pack.tar.gz
  4969. docker run @var{image-id}
  4970. @end example
  4971. @item --expression=@var{expr}
  4972. @itemx -e @var{expr}
  4973. Consider the package @var{expr} evaluates to.
  4974. This has the same purpose as the same-named option in @command{guix
  4975. build} (@pxref{Additional Build Options, @option{--expression} in
  4976. @command{guix build}}).
  4977. @item --manifest=@var{file}
  4978. @itemx -m @var{file}
  4979. Use the packages contained in the manifest object returned by the Scheme
  4980. code in @var{file}. This option can be repeated several times, in which
  4981. case the manifests are concatenated.
  4982. This has a similar purpose as the same-named option in @command{guix
  4983. package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
  4984. same manifest files. It allows you to define a collection of packages
  4985. once and use it both for creating profiles and for creating archives
  4986. for use on machines that do not have Guix installed. Note that you can
  4987. specify @emph{either} a manifest file @emph{or} a list of packages,
  4988. but not both.
  4989. @item --system=@var{system}
  4990. @itemx -s @var{system}
  4991. Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
  4992. the system type of the build host.
  4993. @item --target=@var{triplet}
  4994. @cindex cross-compilation
  4995. Cross-build for @var{triplet}, which must be a valid GNU triplet, such
  4996. as @code{"aarch64-linux-gnu"} (@pxref{Specifying target triplets, GNU
  4997. configuration triplets,, autoconf, Autoconf}).
  4998. @item --compression=@var{tool}
  4999. @itemx -C @var{tool}
  5000. Compress the resulting tarball using @var{tool}---one of @code{gzip},
  5001. @code{zstd}, @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no
  5002. compression.
  5003. @item --symlink=@var{spec}
  5004. @itemx -S @var{spec}
  5005. Add the symlinks specified by @var{spec} to the pack. This option can
  5006. appear several times.
  5007. @var{spec} has the form @code{@var{source}=@var{target}}, where
  5008. @var{source} is the symlink that will be created and @var{target} is the
  5009. symlink target.
  5010. For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
  5011. symlink pointing to the @file{bin} sub-directory of the profile.
  5012. @item --save-provenance
  5013. Save provenance information for the packages passed on the command line.
  5014. Provenance information includes the URL and commit of the channels in use
  5015. (@pxref{Channels}).
  5016. Provenance information is saved in the
  5017. @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
  5018. usual package metadata---the name and version of each package, their
  5019. propagated inputs, and so on. It is useful information to the recipient of
  5020. the pack, who then knows how the pack was (supposedly) obtained.
  5021. This option is not enabled by default because, like timestamps, provenance
  5022. information contributes nothing to the build process. In other words, there
  5023. is an infinity of channel URLs and commit IDs that can lead to the same pack.
  5024. Recording such ``silent'' metadata in the output thus potentially breaks the
  5025. source-to-binary bitwise reproducibility property.
  5026. @item --root=@var{file}
  5027. @itemx -r @var{file}
  5028. @cindex garbage collector root, for packs
  5029. Make @var{file} a symlink to the resulting pack, and register it as a garbage
  5030. collector root.
  5031. @item --localstatedir
  5032. @itemx --profile-name=@var{name}
  5033. Include the ``local state directory'', @file{/var/guix}, in the resulting
  5034. pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
  5035. profile---by default @var{name} is @code{guix-profile}, which corresponds to
  5036. @file{~root/.guix-profile}.
  5037. @file{/var/guix} contains the store database (@pxref{The Store}) as well
  5038. as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
  5039. the pack means that the store is ``complete'' and manageable by Guix;
  5040. not providing it pack means that the store is ``dead'': items cannot be
  5041. added to it or removed from it after extraction of the pack.
  5042. One use case for this is the Guix self-contained binary tarball
  5043. (@pxref{Binary Installation}).
  5044. @item --derivation
  5045. @itemx -d
  5046. Print the name of the derivation that builds the pack.
  5047. @item --bootstrap
  5048. Use the bootstrap binaries to build the pack. This option is only
  5049. useful to Guix developers.
  5050. @end table
  5051. In addition, @command{guix pack} supports all the common build options
  5052. (@pxref{Common Build Options}) and all the package transformation
  5053. options (@pxref{Package Transformation Options}).
  5054. @node The GCC toolchain
  5055. @section The GCC toolchain
  5056. @cindex GCC
  5057. @cindex ld-wrapper
  5058. @cindex linker wrapper
  5059. @cindex toolchain, for C development
  5060. @cindex toolchain, for Fortran development
  5061. If you need a complete toolchain for compiling and linking C or C++
  5062. source code, use the @code{gcc-toolchain} package. This package
  5063. provides a complete GCC toolchain for C/C++ development, including GCC
  5064. itself, the GNU C Library (headers and binaries, plus debugging symbols
  5065. in the @code{debug} output), Binutils, and a linker wrapper.
  5066. The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
  5067. passed to the linker, add corresponding @code{-rpath} arguments, and
  5068. invoke the actual linker with this new set of arguments. You can instruct the
  5069. wrapper to refuse to link against libraries not in the store by setting the
  5070. @env{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
  5071. The package @code{gfortran-toolchain} provides a complete GCC toolchain
  5072. for Fortran development. For other languages, please use
  5073. @samp{guix search gcc toolchain} (@pxref{guix-search,, Invoking guix package}).
  5074. @node Invoking guix git authenticate
  5075. @section Invoking @command{guix git authenticate}
  5076. The @command{guix git authenticate} command authenticates a Git checkout
  5077. following the same rule as for channels (@pxref{channel-authentication,
  5078. channel authentication}). That is, starting from a given commit, it
  5079. ensures that all subsequent commits are signed by an OpenPGP key whose
  5080. fingerprint appears in the @file{.guix-authorizations} file of its
  5081. parent commit(s).
  5082. You will find this command useful if you maintain a channel. But in
  5083. fact, this authentication mechanism is useful in a broader context, so
  5084. you might want to use it for Git repositories that have nothing to do
  5085. with Guix.
  5086. The general syntax is:
  5087. @example
  5088. guix git authenticate @var{commit} @var{signer} [@var{options}@dots{}]
  5089. @end example
  5090. By default, this command authenticates the Git checkout in the current
  5091. directory; it outputs nothing and exits with exit code zero on success
  5092. and non-zero on failure. @var{commit} above denotes the first commit
  5093. where authentication takes place, and @var{signer} is the OpenPGP
  5094. fingerprint of public key used to sign @var{commit}. Together, they
  5095. form a ``channel introduction'' (@pxref{channel-authentication, channel
  5096. introduction}). The options below allow you to fine-tune the process.
  5097. @table @code
  5098. @item --repository=@var{directory}
  5099. @itemx -r @var{directory}
  5100. Open the Git repository in @var{directory} instead of the current
  5101. directory.
  5102. @item --keyring=@var{reference}
  5103. @itemx -k @var{reference}
  5104. Load OpenPGP keyring from @var{reference}, the reference of a branch
  5105. such as @code{origin/keyring} or @code{my-keyring}. The branch must
  5106. contain OpenPGP public keys in @file{.key} files, either in binary form
  5107. or ``ASCII-armored''. By default the keyring is loaded from the branch
  5108. named @code{keyring}.
  5109. @item --stats
  5110. Display commit signing statistics upon completion.
  5111. @item --cache-key=@var{key}
  5112. Previously-authenticated commits are cached in a file under
  5113. @file{~/.cache/guix/authentication}. This option forces the cache to be
  5114. stored in file @var{key} in that directory.
  5115. @item --historical-authorizations=@var{file}
  5116. By default, any commit whose parent commit(s) lack the
  5117. @file{.guix-authorizations} file is considered inauthentic. In
  5118. contrast, this option considers the authorizations in @var{file} for any
  5119. commit that lacks @file{.guix-authorizations}. The format of @var{file}
  5120. is the same as that of @file{.guix-authorizations}
  5121. (@pxref{channel-authorizations, @file{.guix-authorizations} format}).
  5122. @end table
  5123. @c *********************************************************************
  5124. @node Programming Interface
  5125. @chapter Programming Interface
  5126. GNU Guix provides several Scheme programming interfaces (APIs) to
  5127. define, build, and query packages. The first interface allows users to
  5128. write high-level package definitions. These definitions refer to
  5129. familiar packaging concepts, such as the name and version of a package,
  5130. its build system, and its dependencies. These definitions can then be
  5131. turned into concrete build actions.
  5132. Build actions are performed by the Guix daemon, on behalf of users. In a
  5133. standard setup, the daemon has write access to the store---the
  5134. @file{/gnu/store} directory---whereas users do not. The recommended
  5135. setup also has the daemon perform builds in chroots, under specific
  5136. build users, to minimize interference with the rest of the system.
  5137. @cindex derivation
  5138. Lower-level APIs are available to interact with the daemon and the
  5139. store. To instruct the daemon to perform a build action, users actually
  5140. provide it with a @dfn{derivation}. A derivation is a low-level
  5141. representation of the build actions to be taken, and the environment in
  5142. which they should occur---derivations are to package definitions what
  5143. assembly is to C programs. The term ``derivation'' comes from the fact
  5144. that build results @emph{derive} from them.
  5145. This chapter describes all these APIs in turn, starting from high-level
  5146. package definitions.
  5147. @menu
  5148. * Package Modules:: Packages from the programmer's viewpoint.
  5149. * Defining Packages:: Defining new packages.
  5150. * Defining Package Variants:: Customizing packages.
  5151. * Build Systems:: Specifying how packages are built.
  5152. * Build Phases:: Phases of the build process of a package.
  5153. * Build Utilities:: Helpers for your package definitions and more.
  5154. * The Store:: Manipulating the package store.
  5155. * Derivations:: Low-level interface to package derivations.
  5156. * The Store Monad:: Purely functional interface to the store.
  5157. * G-Expressions:: Manipulating build expressions.
  5158. * Invoking guix repl:: Programming Guix in Guile
  5159. @end menu
  5160. @node Package Modules
  5161. @section Package Modules
  5162. From a programming viewpoint, the package definitions of the
  5163. GNU distribution are provided by Guile modules in the @code{(gnu packages
  5164. @dots{})} name space@footnote{Note that packages under the @code{(gnu
  5165. packages @dots{})} module name space are not necessarily ``GNU
  5166. packages''. This module naming scheme follows the usual Guile module
  5167. naming convention: @code{gnu} means that these modules are distributed
  5168. as part of the GNU system, and @code{packages} identifies modules that
  5169. define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
  5170. Reference Manual}). For instance, the @code{(gnu packages emacs)}
  5171. module exports a variable named @code{emacs}, which is bound to a
  5172. @code{<package>} object (@pxref{Defining Packages}).
  5173. The @code{(gnu packages @dots{})} module name space is
  5174. automatically scanned for packages by the command-line tools. For
  5175. instance, when running @code{guix install emacs}, all the @code{(gnu
  5176. packages @dots{})} modules are scanned until one that exports a package
  5177. object whose name is @code{emacs} is found. This package search
  5178. facility is implemented in the @code{(gnu packages)} module.
  5179. @cindex customization, of packages
  5180. @cindex package module search path
  5181. Users can store package definitions in modules with different
  5182. names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
  5183. name and module name must match. For instance, the @code{(my-packages
  5184. emacs)} module must be stored in a @file{my-packages/emacs.scm} file
  5185. relative to the load path specified with @option{--load-path} or
  5186. @env{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
  5187. guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
  5188. these package definitions visible to the user interfaces:
  5189. @enumerate
  5190. @item
  5191. By adding the directory containing your package modules to the search path
  5192. with the @code{-L} flag of @command{guix package} and other commands
  5193. (@pxref{Common Build Options}), or by setting the @env{GUIX_PACKAGE_PATH}
  5194. environment variable described below.
  5195. @item
  5196. By defining a @dfn{channel} and configuring @command{guix pull} so that it
  5197. pulls from it. A channel is essentially a Git repository containing package
  5198. modules. @xref{Channels}, for more information on how to define and use
  5199. channels.
  5200. @end enumerate
  5201. @env{GUIX_PACKAGE_PATH} works similarly to other search path variables:
  5202. @defvr {Environment Variable} GUIX_PACKAGE_PATH
  5203. This is a colon-separated list of directories to search for additional
  5204. package modules. Directories listed in this variable take precedence
  5205. over the own modules of the distribution.
  5206. @end defvr
  5207. The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
  5208. each package is built based solely on other packages in the
  5209. distribution. The root of this dependency graph is a small set of
  5210. @dfn{bootstrap binaries}, provided by the @code{(gnu packages
  5211. bootstrap)} module. For more information on bootstrapping,
  5212. @pxref{Bootstrapping}.
  5213. @node Defining Packages
  5214. @section Defining Packages
  5215. The high-level interface to package definitions is implemented in the
  5216. @code{(guix packages)} and @code{(guix build-system)} modules. As an
  5217. example, the package definition, or @dfn{recipe}, for the GNU Hello
  5218. package looks like this:
  5219. @lisp
  5220. (define-module (gnu packages hello)
  5221. #:use-module (guix packages)
  5222. #:use-module (guix download)
  5223. #:use-module (guix build-system gnu)
  5224. #:use-module (guix licenses)
  5225. #:use-module (gnu packages gawk))
  5226. (define-public hello
  5227. (package
  5228. (name "hello")
  5229. (version "2.10")
  5230. (source (origin
  5231. (method url-fetch)
  5232. (uri (string-append "mirror://gnu/hello/hello-" version
  5233. ".tar.gz"))
  5234. (sha256
  5235. (base32
  5236. "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
  5237. (build-system gnu-build-system)
  5238. (arguments '(#:configure-flags '("--enable-silent-rules")))
  5239. (inputs `(("gawk" ,gawk)))
  5240. (synopsis "Hello, GNU world: An example GNU package")
  5241. (description "Guess what GNU Hello prints!")
  5242. (home-page "https://www.gnu.org/software/hello/")
  5243. (license gpl3+)))
  5244. @end lisp
  5245. @noindent
  5246. Without being a Scheme expert, the reader may have guessed the meaning
  5247. of the various fields here. This expression binds the variable
  5248. @code{hello} to a @code{<package>} object, which is essentially a record
  5249. (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
  5250. This package object can be inspected using procedures found in the
  5251. @code{(guix packages)} module; for instance, @code{(package-name hello)}
  5252. returns---surprise!---@code{"hello"}.
  5253. With luck, you may be able to import part or all of the definition of
  5254. the package you are interested in from another repository, using the
  5255. @code{guix import} command (@pxref{Invoking guix import}).
  5256. In the example above, @code{hello} is defined in a module of its own,
  5257. @code{(gnu packages hello)}. Technically, this is not strictly
  5258. necessary, but it is convenient to do so: all the packages defined in
  5259. modules under @code{(gnu packages @dots{})} are automatically known to
  5260. the command-line tools (@pxref{Package Modules}).
  5261. There are a few points worth noting in the above package definition:
  5262. @itemize
  5263. @item
  5264. The @code{source} field of the package is an @code{<origin>} object
  5265. (@pxref{origin Reference}, for the complete reference).
  5266. Here, the @code{url-fetch} method from @code{(guix download)} is used,
  5267. meaning that the source is a file to be downloaded over FTP or HTTP.
  5268. The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
  5269. the GNU mirrors defined in @code{(guix download)}.
  5270. The @code{sha256} field specifies the expected SHA256 hash of the file
  5271. being downloaded. It is mandatory, and allows Guix to check the
  5272. integrity of the file. The @code{(base32 @dots{})} form introduces the
  5273. base32 representation of the hash. You can obtain this information with
  5274. @code{guix download} (@pxref{Invoking guix download}) and @code{guix
  5275. hash} (@pxref{Invoking guix hash}).
  5276. @cindex patches
  5277. When needed, the @code{origin} form can also have a @code{patches} field
  5278. listing patches to be applied, and a @code{snippet} field giving a
  5279. Scheme expression to modify the source code.
  5280. @item
  5281. @cindex GNU Build System
  5282. The @code{build-system} field specifies the procedure to build the
  5283. package (@pxref{Build Systems}). Here, @code{gnu-build-system}
  5284. represents the familiar GNU Build System, where packages may be
  5285. configured, built, and installed with the usual @code{./configure &&
  5286. make && make check && make install} command sequence.
  5287. When you start packaging non-trivial software, you may need tools to
  5288. manipulate those build phases, manipulate files, and so on. @xref{Build
  5289. Utilities}, for more on this.
  5290. @item
  5291. The @code{arguments} field specifies options for the build system
  5292. (@pxref{Build Systems}). Here it is interpreted by
  5293. @code{gnu-build-system} as a request run @file{configure} with the
  5294. @option{--enable-silent-rules} flag.
  5295. @cindex quote
  5296. @cindex quoting
  5297. @findex '
  5298. @findex quote
  5299. What about these quote (@code{'}) characters? They are Scheme syntax to
  5300. introduce a literal list; @code{'} is synonymous with @code{quote}.
  5301. @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
  5302. for details. Here the value of the @code{arguments} field is a list of
  5303. arguments passed to the build system down the road, as with @code{apply}
  5304. (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
  5305. Manual}).
  5306. The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
  5307. (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
  5308. @code{#:configure-flags} is a keyword used to pass a keyword argument
  5309. to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
  5310. Reference Manual}).
  5311. @item
  5312. The @code{inputs} field specifies inputs to the build process---i.e.,
  5313. build-time or run-time dependencies of the package. Here, we define an
  5314. input called @code{"gawk"} whose value is that of the @code{gawk}
  5315. variable; @code{gawk} is itself bound to a @code{<package>} object.
  5316. @cindex backquote (quasiquote)
  5317. @findex `
  5318. @findex quasiquote
  5319. @cindex comma (unquote)
  5320. @findex ,
  5321. @findex unquote
  5322. @findex ,@@
  5323. @findex unquote-splicing
  5324. Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
  5325. us to introduce a literal list in the @code{inputs} field, while
  5326. @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
  5327. value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
  5328. Reference Manual}).
  5329. Note that GCC, Coreutils, Bash, and other essential tools do not need to
  5330. be specified as inputs here. Instead, @code{gnu-build-system} takes care
  5331. of ensuring that they are present (@pxref{Build Systems}).
  5332. However, any other dependencies need to be specified in the
  5333. @code{inputs} field. Any dependency not specified here will simply be
  5334. unavailable to the build process, possibly leading to a build failure.
  5335. @end itemize
  5336. @xref{package Reference}, for a full description of possible fields.
  5337. Once a package definition is in place, the
  5338. package may actually be built using the @code{guix build} command-line
  5339. tool (@pxref{Invoking guix build}), troubleshooting any build failures
  5340. you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
  5341. package definition using the @command{guix edit} command
  5342. (@pxref{Invoking guix edit}).
  5343. @xref{Packaging Guidelines}, for
  5344. more information on how to test package definitions, and
  5345. @ref{Invoking guix lint}, for information on how to check a definition
  5346. for style conformance.
  5347. @vindex GUIX_PACKAGE_PATH
  5348. Lastly, @pxref{Channels}, for information
  5349. on how to extend the distribution by adding your own package definitions
  5350. in a ``channel''.
  5351. Finally, updating the package definition to a new upstream version
  5352. can be partly automated by the @command{guix refresh} command
  5353. (@pxref{Invoking guix refresh}).
  5354. Behind the scenes, a derivation corresponding to the @code{<package>}
  5355. object is first computed by the @code{package-derivation} procedure.
  5356. That derivation is stored in a @file{.drv} file under @file{/gnu/store}.
  5357. The build actions it prescribes may then be realized by using the
  5358. @code{build-derivations} procedure (@pxref{The Store}).
  5359. @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
  5360. Return the @code{<derivation>} object of @var{package} for @var{system}
  5361. (@pxref{Derivations}).
  5362. @var{package} must be a valid @code{<package>} object, and @var{system}
  5363. must be a string denoting the target system type---e.g.,
  5364. @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
  5365. must be a connection to the daemon, which operates on the store
  5366. (@pxref{The Store}).
  5367. @end deffn
  5368. @noindent
  5369. @cindex cross-compilation
  5370. Similarly, it is possible to compute a derivation that cross-builds a
  5371. package for some other system:
  5372. @deffn {Scheme Procedure} package-cross-derivation @var{store} @
  5373. @var{package} @var{target} [@var{system}]
  5374. Return the @code{<derivation>} object of @var{package} cross-built from
  5375. @var{system} to @var{target}.
  5376. @var{target} must be a valid GNU triplet denoting the target hardware
  5377. and operating system, such as @code{"aarch64-linux-gnu"}
  5378. (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
  5379. @end deffn
  5380. Once you have package definitions, you can easily define @emph{variants}
  5381. of those packages. @xref{Defining Package Variants}, for more on that.
  5382. @menu
  5383. * package Reference:: The package data type.
  5384. * origin Reference:: The origin data type.
  5385. @end menu
  5386. @node package Reference
  5387. @subsection @code{package} Reference
  5388. This section summarizes all the options available in @code{package}
  5389. declarations (@pxref{Defining Packages}).
  5390. @deftp {Data Type} package
  5391. This is the data type representing a package recipe.
  5392. @table @asis
  5393. @item @code{name}
  5394. The name of the package, as a string.
  5395. @item @code{version}
  5396. The version of the package, as a string.
  5397. @item @code{source}
  5398. An object telling how the source code for the package should be
  5399. acquired. Most of the time, this is an @code{origin} object, which
  5400. denotes a file fetched from the Internet (@pxref{origin Reference}). It
  5401. can also be any other ``file-like'' object such as a @code{local-file},
  5402. which denotes a file from the local file system (@pxref{G-Expressions,
  5403. @code{local-file}}).
  5404. @item @code{build-system}
  5405. The build system that should be used to build the package (@pxref{Build
  5406. Systems}).
  5407. @item @code{arguments} (default: @code{'()})
  5408. The arguments that should be passed to the build system. This is a
  5409. list, typically containing sequential keyword-value pairs.
  5410. @item @code{inputs} (default: @code{'()})
  5411. @itemx @code{native-inputs} (default: @code{'()})
  5412. @itemx @code{propagated-inputs} (default: @code{'()})
  5413. @cindex inputs, of packages
  5414. These fields list dependencies of the package. Each one is a list of
  5415. tuples, where each tuple has a label for the input (a string) as its
  5416. first element, a package, origin, or derivation as its second element,
  5417. and optionally the name of the output thereof that should be used, which
  5418. defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
  5419. more on package outputs). For example, the list below specifies three
  5420. inputs:
  5421. @lisp
  5422. `(("libffi" ,libffi)
  5423. ("libunistring" ,libunistring)
  5424. ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
  5425. @end lisp
  5426. @cindex cross compilation, package dependencies
  5427. The distinction between @code{native-inputs} and @code{inputs} is
  5428. necessary when considering cross-compilation. When cross-compiling,
  5429. dependencies listed in @code{inputs} are built for the @emph{target}
  5430. architecture; conversely, dependencies listed in @code{native-inputs}
  5431. are built for the architecture of the @emph{build} machine.
  5432. @code{native-inputs} is typically used to list tools needed at
  5433. build time, but not at run time, such as Autoconf, Automake, pkg-config,
  5434. Gettext, or Bison. @command{guix lint} can report likely mistakes in
  5435. this area (@pxref{Invoking guix lint}).
  5436. @anchor{package-propagated-inputs}
  5437. Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
  5438. specified packages will be automatically installed to profiles
  5439. (@pxref{Features, the role of profiles in Guix}) alongside the package
  5440. they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
  5441. package}}, for information on how @command{guix package} deals with
  5442. propagated inputs).
  5443. For example this is necessary when packaging a C/C++ library that needs
  5444. headers of another library to compile, or when a pkg-config file refers
  5445. to another one @i{via} its @code{Requires} field.
  5446. Another example where @code{propagated-inputs} is useful is for languages
  5447. that lack a facility to record the run-time search path akin to the
  5448. @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
  5449. more. When packaging libraries written in those languages, ensure they
  5450. can find library code they depend on at run time by listing run-time
  5451. dependencies in @code{propagated-inputs} rather than @code{inputs}.
  5452. @item @code{outputs} (default: @code{'("out")})
  5453. The list of output names of the package. @xref{Packages with Multiple
  5454. Outputs}, for typical uses of additional outputs.
  5455. @item @code{native-search-paths} (default: @code{'()})
  5456. @itemx @code{search-paths} (default: @code{'()})
  5457. A list of @code{search-path-specification} objects describing
  5458. search-path environment variables honored by the package.
  5459. @item @code{replacement} (default: @code{#f})
  5460. This must be either @code{#f} or a package object that will be used as a
  5461. @dfn{replacement} for this package. @xref{Security Updates, grafts},
  5462. for details.
  5463. @item @code{synopsis}
  5464. A one-line description of the package.
  5465. @item @code{description}
  5466. A more elaborate description of the package.
  5467. @item @code{license}
  5468. @cindex license, of packages
  5469. The license of the package; a value from @code{(guix licenses)},
  5470. or a list of such values.
  5471. @item @code{home-page}
  5472. The URL to the home-page of the package, as a string.
  5473. @item @code{supported-systems} (default: @code{%supported-systems})
  5474. The list of systems supported by the package, as strings of the form
  5475. @code{architecture-kernel}, for example @code{"x86_64-linux"}.
  5476. @item @code{location} (default: source location of the @code{package} form)
  5477. The source location of the package. It is useful to override this when
  5478. inheriting from another package, in which case this field is not
  5479. automatically corrected.
  5480. @end table
  5481. @end deftp
  5482. @deffn {Scheme Syntax} this-package
  5483. When used in the @emph{lexical scope} of a package field definition, this
  5484. identifier resolves to the package being defined.
  5485. The example below shows how to add a package as a native input of itself when
  5486. cross-compiling:
  5487. @lisp
  5488. (package
  5489. (name "guile")
  5490. ;; ...
  5491. ;; When cross-compiled, Guile, for example, depends on
  5492. ;; a native version of itself. Add it here.
  5493. (native-inputs (if (%current-target-system)
  5494. `(("self" ,this-package))
  5495. '())))
  5496. @end lisp
  5497. It is an error to refer to @code{this-package} outside a package definition.
  5498. @end deffn
  5499. Because packages are regular Scheme objects that capture a complete
  5500. dependency graph and associated build procedures, it is often useful to
  5501. write procedures that take a package and return a modified version
  5502. thereof according to some parameters. Below are a few examples.
  5503. @cindex tool chain, choosing a package's tool chain
  5504. @deffn {Scheme Procedure} package-with-c-toolchain @var{package} @var{toolchain}
  5505. Return a variant of @var{package} that uses @var{toolchain} instead of
  5506. the default GNU C/C++ toolchain. @var{toolchain} must be a list of
  5507. inputs (label/package tuples) providing equivalent functionality, such
  5508. as the @code{gcc-toolchain} package.
  5509. The example below returns a variant of the @code{hello} package built
  5510. with GCC@tie{}10.x and the rest of the GNU tool chain (Binutils and the
  5511. GNU C Library) instead of the default tool chain:
  5512. @lisp
  5513. (let ((toolchain (specification->package "gcc-toolchain@@10")))
  5514. (package-with-c-toolchain hello `(("toolchain" ,toolchain))))
  5515. @end lisp
  5516. The build tool chain is part of the @dfn{implicit inputs} of
  5517. packages---it's usually not listed as part of the various ``inputs''
  5518. fields and is instead pulled in by the build system. Consequently, this
  5519. procedure works by changing the build system of @var{package} so that it
  5520. pulls in @var{toolchain} instead of the defaults. @ref{Build Systems},
  5521. for more on build systems.
  5522. @end deffn
  5523. @node origin Reference
  5524. @subsection @code{origin} Reference
  5525. This section documents @dfn{origins}. An @code{origin} declaration
  5526. specifies data that must be ``produced''---downloaded, usually---and
  5527. whose content hash is known in advance. Origins are primarily used to
  5528. represent the source code of packages (@pxref{Defining Packages}). For
  5529. that reason, the @code{origin} form allows you to declare patches to
  5530. apply to the original source code as well as code snippets to modify it.
  5531. @deftp {Data Type} origin
  5532. This is the data type representing a source code origin.
  5533. @table @asis
  5534. @item @code{uri}
  5535. An object containing the URI of the source. The object type depends on
  5536. the @code{method} (see below). For example, when using the
  5537. @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
  5538. values are: a URL represented as a string, or a list thereof.
  5539. @cindex fixed-output derivations, for download
  5540. @item @code{method}
  5541. A monadic procedure that handles the given URI@. The procedure must
  5542. accept at least three arguments: the value of the @code{uri} field and
  5543. the hash algorithm and hash value specified by the @code{hash} field.
  5544. It must return a store item or a derivation in the store monad
  5545. (@pxref{The Store Monad}); most methods return a fixed-output derivation
  5546. (@pxref{Derivations}).
  5547. Commonly used methods include @code{url-fetch}, which fetches data from
  5548. a URL, and @code{git-fetch}, which fetches data from a Git repository
  5549. (see below).
  5550. @item @code{sha256}
  5551. A bytevector containing the SHA-256 hash of the source. This is
  5552. equivalent to providing a @code{content-hash} SHA256 object in the
  5553. @code{hash} field described below.
  5554. @item @code{hash}
  5555. The @code{content-hash} object of the source---see below for how to use
  5556. @code{content-hash}.
  5557. You can obtain this information using @code{guix download}
  5558. (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
  5559. guix hash}).
  5560. @item @code{file-name} (default: @code{#f})
  5561. The file name under which the source code should be saved. When this is
  5562. @code{#f}, a sensible default value will be used in most cases. In case
  5563. the source is fetched from a URL, the file name from the URL will be
  5564. used. For version control checkouts, it is recommended to provide the
  5565. file name explicitly because the default is not very descriptive.
  5566. @item @code{patches} (default: @code{'()})
  5567. A list of file names, origins, or file-like objects (@pxref{G-Expressions,
  5568. file-like objects}) pointing to patches to be applied to the source.
  5569. This list of patches must be unconditional. In particular, it cannot
  5570. depend on the value of @code{%current-system} or
  5571. @code{%current-target-system}.
  5572. @item @code{snippet} (default: @code{#f})
  5573. A G-expression (@pxref{G-Expressions}) or S-expression that will be run
  5574. in the source directory. This is a convenient way to modify the source,
  5575. sometimes more convenient than a patch.
  5576. @item @code{patch-flags} (default: @code{'("-p1")})
  5577. A list of command-line flags that should be passed to the @code{patch}
  5578. command.
  5579. @item @code{patch-inputs} (default: @code{#f})
  5580. Input packages or derivations to the patching process. When this is
  5581. @code{#f}, the usual set of inputs necessary for patching are provided,
  5582. such as GNU@tie{}Patch.
  5583. @item @code{modules} (default: @code{'()})
  5584. A list of Guile modules that should be loaded during the patching
  5585. process and while running the code in the @code{snippet} field.
  5586. @item @code{patch-guile} (default: @code{#f})
  5587. The Guile package that should be used in the patching process. When
  5588. this is @code{#f}, a sensible default is used.
  5589. @end table
  5590. @end deftp
  5591. @deftp {Data Type} content-hash @var{value} [@var{algorithm}]
  5592. Construct a content hash object for the given @var{algorithm}, and with
  5593. @var{value} as its hash value. When @var{algorithm} is omitted, assume
  5594. it is @code{sha256}.
  5595. @var{value} can be a literal string, in which case it is base32-decoded,
  5596. or it can be a bytevector.
  5597. The following forms are all equivalent:
  5598. @lisp
  5599. (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj")
  5600. (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"
  5601. sha256)
  5602. (content-hash (base32
  5603. "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"))
  5604. (content-hash (base64 "kkb+RPaP7uyMZmu4eXPVkM4BN8yhRd8BTHLslb6f/Rc=")
  5605. sha256)
  5606. @end lisp
  5607. Technically, @code{content-hash} is currently implemented as a macro.
  5608. It performs sanity checks at macro-expansion time, when possible, such
  5609. as ensuring that @var{value} has the right size for @var{algorithm}.
  5610. @end deftp
  5611. As we have seen above, how exactly the data an origin refers to is
  5612. retrieved is determined by its @code{method} field. The @code{(guix
  5613. download)} module provides the most common method, @code{url-fetch},
  5614. described below.
  5615. @deffn {Scheme Procedure} url-fetch @var{url} @var{hash-algo} @var{hash} @
  5616. [name] [#:executable? #f]
  5617. Return a fixed-output derivation that fetches data from @var{url} (a
  5618. string, or a list of strings denoting alternate URLs), which is expected
  5619. to have hash @var{hash} of type @var{hash-algo} (a symbol). By default,
  5620. the file name is the base name of URL; optionally, @var{name} can
  5621. specify a different file name. When @var{executable?} is true, make the
  5622. downloaded file executable.
  5623. When one of the URL starts with @code{mirror://}, then its host part is
  5624. interpreted as the name of a mirror scheme, taken from @file{%mirror-file}.
  5625. Alternatively, when URL starts with @code{file://}, return the
  5626. corresponding file name in the store.
  5627. @end deffn
  5628. Likewise, the @code{(guix git-download)} module defines the
  5629. @code{git-fetch} origin method, which fetches data from a Git version
  5630. control repository, and the @code{git-reference} data type to describe
  5631. the repository and revision to fetch.
  5632. @deffn {Scheme Procedure} git-fetch @var{ref} @var{hash-algo} @var{hash}
  5633. Return a fixed-output derivation that fetches @var{ref}, a
  5634. @code{<git-reference>} object. The output is expected to have recursive
  5635. hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
  5636. the file name, or a generic name if @code{#f}.
  5637. @end deffn
  5638. @deftp {Data Type} git-reference
  5639. This data type represents a Git reference for @code{git-fetch} to
  5640. retrieve.
  5641. @table @asis
  5642. @item @code{url}
  5643. The URL of the Git repository to clone.
  5644. @item @code{commit}
  5645. This string denotes either the commit to fetch (a hexadecimal string,
  5646. either the full SHA1 commit or a ``short'' commit string; the latter is
  5647. not recommended) or the tag to fetch.
  5648. @item @code{recursive?} (default: @code{#f})
  5649. This Boolean indicates whether to recursively fetch Git sub-modules.
  5650. @end table
  5651. The example below denotes the @code{v2.10} tag of the GNU@tie{}Hello
  5652. repository:
  5653. @lisp
  5654. (git-reference
  5655. (url "https://git.savannah.gnu.org/git/hello.git")
  5656. (commit "v2.10"))
  5657. @end lisp
  5658. This is equivalent to the reference below, which explicitly names the
  5659. commit:
  5660. @lisp
  5661. (git-reference
  5662. (url "https://git.savannah.gnu.org/git/hello.git")
  5663. (commit "dc7dc56a00e48fe6f231a58f6537139fe2908fb9"))
  5664. @end lisp
  5665. @end deftp
  5666. For Mercurial repositories, the module @code{(guix hg-download)} defines
  5667. the @code{hg-fetch} origin method and @code{hg-reference} data type for
  5668. support of the Mercurial version control system.
  5669. @deffn {Scheme Procedure} hg-fetch @var{ref} @var{hash-algo} @var{hash} @
  5670. [name]
  5671. Return a fixed-output derivation that fetches @var{ref}, a
  5672. @code{<hg-reference>} object. The output is expected to have recursive
  5673. hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
  5674. the file name, or a generic name if @code{#false}.
  5675. @end deffn
  5676. @node Defining Package Variants
  5677. @section Defining Package Variants
  5678. @cindex customizing packages
  5679. @cindex variants, of packages
  5680. One of the nice things with Guix is that, given a package definition,
  5681. you can easily @emph{derive} variants of that package---for a different
  5682. upstream version, with different dependencies, different compilation
  5683. options, and so on. Some of these custom packages can be defined
  5684. straight from the command line (@pxref{Package Transformation Options}).
  5685. This section describes how to define package variants in code. This can
  5686. be useful in ``manifests'' (@pxref{profile-manifest,
  5687. @option{--manifest}}) and in your own package collection
  5688. (@pxref{Creating a Channel}), among others!
  5689. @cindex inherit, for package definitions
  5690. As discussed earlier, packages are first-class objects in the Scheme
  5691. language. The @code{(guix packages)} module provides the @code{package}
  5692. construct to define new package objects (@pxref{package Reference}).
  5693. The easiest way to define a package variant is using the @code{inherit}
  5694. keyword together with @code{package}. This allows you to inherit from a
  5695. package definition while overriding the fields you want.
  5696. For example, given the @code{hello} variable, which contains a
  5697. definition for the current version of GNU@tie{}Hello, here's how you
  5698. would define a variant for version 2.2 (released in 2006, it's
  5699. vintage!):
  5700. @lisp
  5701. (use-modules (gnu packages base)) ;for 'hello'
  5702. (define hello-2.2
  5703. (package
  5704. (inherit hello)
  5705. (version "2.2")
  5706. (source (origin
  5707. (method url-fetch)
  5708. (uri (string-append "mirror://gnu/hello/hello-" version
  5709. ".tar.gz"))
  5710. (sha256
  5711. (base32
  5712. "0lappv4slgb5spyqbh6yl5r013zv72yqg2pcl30mginf3wdqd8k9"))))))
  5713. @end lisp
  5714. The example above corresponds to what the @option{--with-source} package
  5715. transformation option does. Essentially @code{hello-2.2} preserves all
  5716. the fields of @code{hello}, except @code{version} and @code{source},
  5717. which it overrides. Note that the original @code{hello} variable is
  5718. still there, in the @code{(gnu packages base)} module, unchanged. When
  5719. you define a custom package like this, you are really @emph{adding} a
  5720. new package definition; the original one remains available.
  5721. You can just as well define variants with a different set of
  5722. dependencies than the original package. For example, the default
  5723. @code{gdb} package depends on @code{guile}, but since that is an
  5724. optional dependency, you can define a variant that removes that
  5725. dependency like so:
  5726. @lisp
  5727. (use-modules (gnu packages gdb) ;for 'gdb'
  5728. (srfi srfi-1)) ;for 'alist-delete'
  5729. (define gdb-sans-guile
  5730. (package
  5731. (inherit gdb)
  5732. (inputs (alist-delete "guile"
  5733. (package-inputs gdb)))))
  5734. @end lisp
  5735. The @code{alist-delete} call above removes the tuple from the
  5736. @code{inputs} field that has @code{"guile"} as its first element
  5737. (@pxref{SRFI-1 Association Lists,,, guile, GNU Guile Reference
  5738. Manual}).
  5739. In some cases, you may find it useful to write functions
  5740. (``procedures'', in Scheme parlance) that return a package based on some
  5741. parameters. For example, consider the @code{luasocket} library for the
  5742. Lua programming language. We want to create @code{luasocket} packages
  5743. for major versions of Lua. One way to do that is to define a procedure
  5744. that takes a Lua package and returns a @code{luasocket} package that
  5745. depends on it:
  5746. @lisp
  5747. (define (make-lua-socket name lua)
  5748. ;; Return a luasocket package built with LUA.
  5749. (package
  5750. (name name)
  5751. (version "3.0")
  5752. ;; several fields omitted
  5753. (inputs
  5754. `(("lua" ,lua)))
  5755. (synopsis "Socket library for Lua")))
  5756. (define-public lua5.1-socket
  5757. (make-lua-socket "lua5.1-socket" lua-5.1))
  5758. (define-public lua5.2-socket
  5759. (make-lua-socket "lua5.2-socket" lua-5.2))
  5760. @end lisp
  5761. Here we have defined packages @code{lua5.1-socket} and
  5762. @code{lua5.2-socket} by calling @code{make-lua-socket} with different
  5763. arguments. @xref{Procedures,,, guile, GNU Guile Reference Manual}, for
  5764. more info on procedures. Having top-level public definitions for these
  5765. two packages means that they can be referred to from the command line
  5766. (@pxref{Package Modules}).
  5767. @cindex package transformations
  5768. These are pretty simple package variants. As a convenience, the
  5769. @code{(guix transformations)} module provides a high-level interface
  5770. that directly maps to the more sophisticated package transformation
  5771. options (@pxref{Package Transformation Options}):
  5772. @deffn {Scheme Procedure} options->transformation @var{opts}
  5773. Return a procedure that, when passed an object to build (package,
  5774. derivation, etc.), applies the transformations specified by @var{opts} and returns
  5775. the resulting objects. @var{opts} must be a list of symbol/string pairs such as:
  5776. @lisp
  5777. ((with-branch . "guile-gcrypt=master")
  5778. (without-tests . "libgcrypt"))
  5779. @end lisp
  5780. Each symbol names a transformation and the corresponding string is an argument
  5781. to that transformation.
  5782. @end deffn
  5783. For instance, a manifest equivalent to this command:
  5784. @example
  5785. guix build guix \
  5786. --with-branch=guile-gcrypt=master \
  5787. --with-debug-info=zlib
  5788. @end example
  5789. @noindent
  5790. ... would look like this:
  5791. @lisp
  5792. (use-modules (guix transformations))
  5793. (define transform
  5794. ;; The package transformation procedure.
  5795. (options->transformation
  5796. '((with-branch . "guile-gcrypt=master")
  5797. (with-debug-info . "zlib"))))
  5798. (packages->manifest
  5799. (list (transform (specification->package "guix"))))
  5800. @end lisp
  5801. @cindex input rewriting
  5802. @cindex dependency graph rewriting
  5803. The @code{options->transformation} procedure is convenient, but it's
  5804. perhaps also not as flexible as you may like. How is it implemented?
  5805. The astute reader probably noticed that most package transformation
  5806. options go beyond the superficial changes shown in the first examples of
  5807. this section: they involve @dfn{input rewriting}, whereby the dependency
  5808. graph of a package is rewritten by replacing specific inputs by others.
  5809. Dependency graph rewriting, for the purposes of swapping packages in the
  5810. graph, is what the @code{package-input-rewriting} procedure in
  5811. @code{(guix packages)} implements.
  5812. @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
  5813. [@var{rewrite-name}] [#:deep? #t]
  5814. Return a procedure that, when passed a package, replaces its direct and
  5815. indirect dependencies, including implicit inputs when @var{deep?} is
  5816. true, according to @var{replacements}. @var{replacements} is a list of
  5817. package pairs; the first element of each pair is the package to replace,
  5818. and the second one is the replacement.
  5819. Optionally, @var{rewrite-name} is a one-argument procedure that takes
  5820. the name of a package and returns its new name after rewrite.
  5821. @end deffn
  5822. @noindent
  5823. Consider this example:
  5824. @lisp
  5825. (define libressl-instead-of-openssl
  5826. ;; This is a procedure to replace OPENSSL by LIBRESSL,
  5827. ;; recursively.
  5828. (package-input-rewriting `((,openssl . ,libressl))))
  5829. (define git-with-libressl
  5830. (libressl-instead-of-openssl git))
  5831. @end lisp
  5832. @noindent
  5833. Here we first define a rewriting procedure that replaces @var{openssl}
  5834. with @var{libressl}. Then we use it to define a @dfn{variant} of the
  5835. @var{git} package that uses @var{libressl} instead of @var{openssl}.
  5836. This is exactly what the @option{--with-input} command-line option does
  5837. (@pxref{Package Transformation Options, @option{--with-input}}).
  5838. The following variant of @code{package-input-rewriting} can match packages to
  5839. be replaced by name rather than by identity.
  5840. @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements} [#:deep? #t]
  5841. Return a procedure that, given a package, applies the given
  5842. @var{replacements} to all the package graph, including implicit inputs
  5843. unless @var{deep?} is false. @var{replacements} is a list of
  5844. spec/procedures pair; each spec is a package specification such as
  5845. @code{"gcc"} or @code{"guile@@2"}, and each procedure takes a matching
  5846. package and returns a replacement for that package.
  5847. @end deffn
  5848. The example above could be rewritten this way:
  5849. @lisp
  5850. (define libressl-instead-of-openssl
  5851. ;; Replace all the packages called "openssl" with LibreSSL.
  5852. (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
  5853. @end lisp
  5854. The key difference here is that, this time, packages are matched by spec and
  5855. not by identity. In other words, any package in the graph that is called
  5856. @code{openssl} will be replaced.
  5857. A more generic procedure to rewrite a package dependency graph is
  5858. @code{package-mapping}: it supports arbitrary changes to nodes in the
  5859. graph.
  5860. @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}] [#:deep? #f]
  5861. Return a procedure that, given a package, applies @var{proc} to all the packages
  5862. depended on and returns the resulting package. The procedure stops recursion
  5863. when @var{cut?} returns true for a given package. When @var{deep?} is true, @var{proc} is
  5864. applied to implicit inputs as well.
  5865. @end deffn
  5866. @node Build Systems
  5867. @section Build Systems
  5868. @cindex build system
  5869. Each package definition specifies a @dfn{build system} and arguments for
  5870. that build system (@pxref{Defining Packages}). This @code{build-system}
  5871. field represents the build procedure of the package, as well as implicit
  5872. dependencies of that build procedure.
  5873. Build systems are @code{<build-system>} objects. The interface to
  5874. create and manipulate them is provided by the @code{(guix build-system)}
  5875. module, and actual build systems are exported by specific modules.
  5876. @cindex bag (low-level package representation)
  5877. Under the hood, build systems first compile package objects to
  5878. @dfn{bags}. A @dfn{bag} is like a package, but with less
  5879. ornamentation---in other words, a bag is a lower-level representation of
  5880. a package, which includes all the inputs of that package, including some
  5881. that were implicitly added by the build system. This intermediate
  5882. representation is then compiled to a derivation (@pxref{Derivations}).
  5883. The @code{package-with-c-toolchain} is an example of a way to change the
  5884. implicit inputs that a package's build system pulls in (@pxref{package
  5885. Reference, @code{package-with-c-toolchain}}).
  5886. Build systems accept an optional list of @dfn{arguments}. In package
  5887. definitions, these are passed @i{via} the @code{arguments} field
  5888. (@pxref{Defining Packages}). They are typically keyword arguments
  5889. (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
  5890. Guile Reference Manual}). The value of these arguments is usually
  5891. evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
  5892. by the daemon (@pxref{Derivations}).
  5893. The main build system is @code{gnu-build-system}, which implements the
  5894. standard build procedure for GNU and many other packages. It
  5895. is provided by the @code{(guix build-system gnu)} module.
  5896. @defvr {Scheme Variable} gnu-build-system
  5897. @code{gnu-build-system} represents the GNU Build System, and variants
  5898. thereof (@pxref{Configuration, configuration and makefile conventions,,
  5899. standards, GNU Coding Standards}).
  5900. @cindex build phases
  5901. In a nutshell, packages using it are configured, built, and installed with
  5902. the usual @code{./configure && make && make check && make install}
  5903. command sequence. In practice, a few additional steps are often needed.
  5904. All these steps are split up in separate @dfn{phases},
  5905. notably@footnote{Please see the @code{(guix build gnu-build-system)}
  5906. modules for more details about the build phases.}:
  5907. @table @code
  5908. @item unpack
  5909. Unpack the source tarball, and change the current directory to the
  5910. extracted source tree. If the source is actually a directory, copy it
  5911. to the build tree, and enter that directory.
  5912. @item patch-source-shebangs
  5913. Patch shebangs encountered in source files so they refer to the right
  5914. store file names. For instance, this changes @code{#!/bin/sh} to
  5915. @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
  5916. @item configure
  5917. Run the @file{configure} script with a number of default options, such
  5918. as @option{--prefix=/gnu/store/@dots{}}, as well as the options specified
  5919. by the @code{#:configure-flags} argument.
  5920. @item build
  5921. Run @code{make} with the list of flags specified with
  5922. @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
  5923. (the default), build with @code{make -j}.
  5924. @item check
  5925. Run @code{make check}, or some other target specified with
  5926. @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
  5927. @code{#:parallel-tests?} argument is true (the default), run @code{make
  5928. check -j}.
  5929. @item install
  5930. Run @code{make install} with the flags listed in @code{#:make-flags}.
  5931. @item patch-shebangs
  5932. Patch shebangs on the installed executable files.
  5933. @item strip
  5934. Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
  5935. is false), copying them to the @code{debug} output when available
  5936. (@pxref{Installing Debugging Files}).
  5937. @end table
  5938. @vindex %standard-phases
  5939. The build-side module @code{(guix build gnu-build-system)} defines
  5940. @code{%standard-phases} as the default list of build phases.
  5941. @code{%standard-phases} is a list of symbol/procedure pairs, where the
  5942. procedure implements the actual phase.
  5943. @xref{Build Phases}, for more info on build phases and ways to customize
  5944. them.
  5945. In addition, this build system ensures that the ``standard'' environment
  5946. for GNU packages is available. This includes tools such as GCC, libc,
  5947. Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
  5948. build-system gnu)} module for a complete list). We call these the
  5949. @dfn{implicit inputs} of a package, because package definitions do not
  5950. have to mention them.
  5951. @end defvr
  5952. Other @code{<build-system>} objects are defined to support other
  5953. conventions and tools used by free software packages. They inherit most
  5954. of @code{gnu-build-system}, and differ mainly in the set of inputs
  5955. implicitly added to the build process, and in the list of phases
  5956. executed. Some of these build systems are listed below.
  5957. @defvr {Scheme Variable} ant-build-system
  5958. This variable is exported by @code{(guix build-system ant)}. It
  5959. implements the build procedure for Java packages that can be built with
  5960. @url{https://ant.apache.org/, Ant build tool}.
  5961. It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
  5962. provided by the @code{icedtea} package to the set of inputs. Different
  5963. packages can be specified with the @code{#:ant} and @code{#:jdk}
  5964. parameters, respectively.
  5965. When the original package does not provide a suitable Ant build file,
  5966. the parameter @code{#:jar-name} can be used to generate a minimal Ant
  5967. build file @file{build.xml} with tasks to build the specified jar
  5968. archive. In this case the parameter @code{#:source-dir} can be used to
  5969. specify the source sub-directory, defaulting to ``src''.
  5970. The @code{#:main-class} parameter can be used with the minimal ant
  5971. buildfile to specify the main class of the resulting jar. This makes the
  5972. jar file executable. The @code{#:test-include} parameter can be used to
  5973. specify the list of junit tests to run. It defaults to
  5974. @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
  5975. disable some tests. It defaults to @code{(list "**/Abstract*.java")},
  5976. because abstract classes cannot be run as tests.
  5977. The parameter @code{#:build-target} can be used to specify the Ant task
  5978. that should be run during the @code{build} phase. By default the
  5979. ``jar'' task will be run.
  5980. @end defvr
  5981. @defvr {Scheme Variable} android-ndk-build-system
  5982. @cindex Android distribution
  5983. @cindex Android NDK build system
  5984. This variable is exported by @code{(guix build-system android-ndk)}. It
  5985. implements a build procedure for Android NDK (native development kit)
  5986. packages using a Guix-specific build process.
  5987. The build system assumes that packages install their public interface
  5988. (header) files to the subdirectory @file{include} of the @code{out} output and
  5989. their libraries to the subdirectory @file{lib} the @code{out} output.
  5990. It's also assumed that the union of all the dependencies of a package
  5991. has no conflicting files.
  5992. For the time being, cross-compilation is not supported - so right now
  5993. the libraries and header files are assumed to be host tools.
  5994. @end defvr
  5995. @defvr {Scheme Variable} asdf-build-system/source
  5996. @defvrx {Scheme Variable} asdf-build-system/sbcl
  5997. @defvrx {Scheme Variable} asdf-build-system/ecl
  5998. These variables, exported by @code{(guix build-system asdf)}, implement
  5999. build procedures for Common Lisp packages using
  6000. @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
  6001. definition facility for Common Lisp programs and libraries.
  6002. The @code{asdf-build-system/source} system installs the packages in
  6003. source form, and can be loaded using any common lisp implementation, via
  6004. ASDF@. The others, such as @code{asdf-build-system/sbcl}, install binary
  6005. systems in the format which a particular implementation understands.
  6006. These build systems can also be used to produce executable programs, or
  6007. lisp images which contain a set of packages pre-loaded.
  6008. The build system uses naming conventions. For binary packages, the
  6009. package name should be prefixed with the lisp implementation, such as
  6010. @code{sbcl-} for @code{asdf-build-system/sbcl}.
  6011. Additionally, the corresponding source package should be labeled using
  6012. the same convention as python packages (see @ref{Python Modules}), using
  6013. the @code{cl-} prefix.
  6014. In order to create executable programs and images, the build-side
  6015. procedures @code{build-program} and @code{build-image} can be used.
  6016. They should be called in a build phase after the
  6017. @code{create-asdf-configuration} phase, so that the system which was
  6018. just built can be used within the resulting image. @code{build-program}
  6019. requires a list of Common Lisp expressions to be passed as the
  6020. @code{#:entry-program} argument.
  6021. By default, all the @file{.asd} files present in the sources are read to
  6022. find system definitions. The @code{#:asd-files} parameter can be used
  6023. to specify the list of @file{.asd} files to read. Furthermore, if the
  6024. package defines a system for its tests in a separate file, it will be
  6025. loaded before the tests are run if it is specified by the
  6026. @code{#:test-asd-file} parameter. If it is not set, the files
  6027. @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
  6028. and @code{test.asd} will be tried if they exist.
  6029. If for some reason the package must be named in a different way than the
  6030. naming conventions suggest, or if several systems must be compiled, the
  6031. @code{#:asd-systems} parameter can be used to specify the list of system
  6032. names.
  6033. @end defvr
  6034. @defvr {Scheme Variable} cargo-build-system
  6035. @cindex Rust programming language
  6036. @cindex Cargo (Rust build system)
  6037. This variable is exported by @code{(guix build-system cargo)}. It
  6038. supports builds of packages using Cargo, the build tool of the
  6039. @uref{https://www.rust-lang.org, Rust programming language}.
  6040. It adds @code{rustc} and @code{cargo} to the set of inputs.
  6041. A different Rust package can be specified with the @code{#:rust} parameter.
  6042. Regular cargo dependencies should be added to the package definition similarly
  6043. to other packages; those needed only at build time to native-inputs, others to
  6044. inputs. If you need to add source-only crates then you should add them to via
  6045. the @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
  6046. spec can be a package or a source definition. Note that the spec must
  6047. evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
  6048. file at its root, or it will be ignored. Similarly, cargo dev-dependencies
  6049. should be added to the package definition via the
  6050. @code{#:cargo-development-inputs} parameter.
  6051. In its @code{configure} phase, this build system will make any source inputs
  6052. specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
  6053. parameters available to cargo. It will also remove an included
  6054. @code{Cargo.lock} file to be recreated by @code{cargo} during the
  6055. @code{build} phase. The @code{package} phase will run @code{cargo package}
  6056. to create a source crate for future use. The @code{install} phase installs
  6057. the binaries defined by the crate. Unless @code{install-source? #f} is
  6058. defined it will also install a source crate repository of itself and unpacked
  6059. sources, to ease in future hacking on rust packages.
  6060. @end defvr
  6061. @defvr {Scheme Variable} chicken-build-system
  6062. This variable is exported by @code{(guix build-system chicken)}. It
  6063. builds @uref{https://call-cc.org/, CHICKEN Scheme} modules, also called
  6064. ``eggs'' or ``extensions''. CHICKEN generates C source code, which then
  6065. gets compiled by a C compiler, in this case GCC.
  6066. This build system adds @code{chicken} to the package inputs, as well as
  6067. the packages of @code{gnu-build-system}.
  6068. The build system can't (yet) deduce the egg's name automatically, so just like
  6069. with @code{go-build-system} and its @code{#:import-path}, you should define
  6070. @code{#:egg-name} in the package's @code{arguments} field.
  6071. For example, if you are packaging the @code{srfi-1} egg:
  6072. @lisp
  6073. (arguments '(#:egg-name "srfi-1"))
  6074. @end lisp
  6075. Egg dependencies must be defined in @code{propagated-inputs}, not @code{inputs}
  6076. because CHICKEN doesn't embed absolute references in compiled eggs.
  6077. Test dependencies should go to @code{native-inputs}, as usual.
  6078. @end defvr
  6079. @defvr {Scheme Variable} copy-build-system
  6080. This variable is exported by @code{(guix build-system copy)}. It
  6081. supports builds of simple packages that don't require much compiling,
  6082. mostly just moving files around.
  6083. It adds much of the @code{gnu-build-system} packages to the set of
  6084. inputs. Because of this, the @code{copy-build-system} does not require
  6085. all the boilerplate code often needed for the
  6086. @code{trivial-build-system}.
  6087. To further simplify the file installation process, an
  6088. @code{#:install-plan} argument is exposed to let the packager specify
  6089. which files go where. The install plan is a list of @code{(@var{source}
  6090. @var{target} [@var{filters}])}. @var{filters} are optional.
  6091. @itemize
  6092. @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
  6093. @itemize
  6094. @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
  6095. @item Otherwise install @var{source} as @var{target}.
  6096. @end itemize
  6097. @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
  6098. the trailing slash of @var{target} is implied with the same meaning
  6099. as above.
  6100. @itemize
  6101. @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
  6102. @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
  6103. @code{#:exclude-regexp}, only select files are installed depending on
  6104. the filters. Each filters is specified by a list of strings.
  6105. @itemize
  6106. @item With @code{#:include}, install all the files which the path suffix matches
  6107. at least one of the elements in the given list.
  6108. @item With @code{#:include-regexp}, install all the files which the
  6109. subpaths match at least one of the regular expressions in the given
  6110. list.
  6111. @item The @code{#:exclude} and @code{#:exclude-regexp} filters
  6112. are the complement of their inclusion counterpart. Without @code{#:include} flags,
  6113. install all files but those matching the exclusion filters.
  6114. If both inclusions and exclusions are specified, the exclusions are done
  6115. on top of the inclusions.
  6116. @end itemize
  6117. @end itemize
  6118. In all cases, the paths relative to @var{source} are preserved within
  6119. @var{target}.
  6120. @end itemize
  6121. Examples:
  6122. @itemize
  6123. @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
  6124. @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
  6125. @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
  6126. e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
  6127. @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
  6128. @file{share/my-app/sub/file}.
  6129. @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
  6130. @file{share/my-app/file}.
  6131. @end itemize
  6132. @end defvr
  6133. @cindex Clojure (programming language)
  6134. @cindex simple Clojure build system
  6135. @defvr {Scheme Variable} clojure-build-system
  6136. This variable is exported by @code{(guix build-system clojure)}. It implements
  6137. a simple build procedure for @uref{https://clojure.org/, Clojure} packages
  6138. using plain old @code{compile} in Clojure. Cross-compilation is not supported
  6139. yet.
  6140. It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
  6141. Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
  6142. @code{#:zip} parameters, respectively.
  6143. A list of source directories, test directories and jar names can be specified
  6144. with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
  6145. parameters, respectively. Compile directory and main class can be specified
  6146. with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
  6147. Other parameters are documented below.
  6148. This build system is an extension of @code{ant-build-system}, but with the
  6149. following phases changed:
  6150. @table @code
  6151. @item build
  6152. This phase calls @code{compile} in Clojure to compile source files and runs
  6153. @command{jar} to create jars from both source files and compiled files
  6154. according to the include list and exclude list specified in
  6155. @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
  6156. has priority over the include list. These lists consist of symbols
  6157. representing Clojure libraries or the special keyword @code{#:all} representing
  6158. all Clojure libraries found under the source directories. The parameter
  6159. @code{#:omit-source?} decides if source should be included into the jars.
  6160. @item check
  6161. This phase runs tests according to the include list and exclude list specified
  6162. in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
  6163. meanings are analogous to that of @code{#:aot-include} and
  6164. @code{#:aot-exclude}, except that the special keyword @code{#:all} now
  6165. stands for all Clojure libraries found under the test directories. The
  6166. parameter @code{#:tests?} decides if tests should be run.
  6167. @item install
  6168. This phase installs all jars built previously.
  6169. @end table
  6170. Apart from the above, this build system also contains an additional phase:
  6171. @table @code
  6172. @item install-doc
  6173. This phase installs all top-level files with base name matching
  6174. @code{%doc-regex}. A different regex can be specified with the
  6175. @code{#:doc-regex} parameter. All files (recursively) inside the documentation
  6176. directories specified in @code{#:doc-dirs} are installed as well.
  6177. @end table
  6178. @end defvr
  6179. @defvr {Scheme Variable} cmake-build-system
  6180. This variable is exported by @code{(guix build-system cmake)}. It
  6181. implements the build procedure for packages using the
  6182. @url{https://www.cmake.org, CMake build tool}.
  6183. It automatically adds the @code{cmake} package to the set of inputs.
  6184. Which package is used can be specified with the @code{#:cmake}
  6185. parameter.
  6186. The @code{#:configure-flags} parameter is taken as a list of flags
  6187. passed to the @command{cmake} command. The @code{#:build-type}
  6188. parameter specifies in abstract terms the flags passed to the compiler;
  6189. it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
  6190. debugging information''), which roughly means that code is compiled with
  6191. @code{-O2 -g}, as is the case for Autoconf-based packages by default.
  6192. @end defvr
  6193. @defvr {Scheme Variable} dune-build-system
  6194. This variable is exported by @code{(guix build-system dune)}. It
  6195. supports builds of packages using @uref{https://dune.build/, Dune}, a build
  6196. tool for the OCaml programming language. It is implemented as an extension
  6197. of the @code{ocaml-build-system} which is described below. As such, the
  6198. @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
  6199. system.
  6200. It automatically adds the @code{dune} package to the set of inputs.
  6201. Which package is used can be specified with the @code{#:dune}
  6202. parameter.
  6203. There is no @code{configure} phase because dune packages typically don't
  6204. need to be configured. The @code{#:build-flags} parameter is taken as a
  6205. list of flags passed to the @code{dune} command during the build.
  6206. The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
  6207. command instead of the more recent @code{dune} command while building
  6208. a package. Its default value is @code{#f}.
  6209. The @code{#:package} parameter can be passed to specify a package name, which
  6210. is useful when a package contains multiple packages and you want to build
  6211. only one of them. This is equivalent to passing the @code{-p} argument to
  6212. @code{dune}.
  6213. @end defvr
  6214. @defvr {Scheme Variable} go-build-system
  6215. This variable is exported by @code{(guix build-system go)}. It
  6216. implements a build procedure for Go packages using the standard
  6217. @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
  6218. Go build mechanisms}.
  6219. The user is expected to provide a value for the key @code{#:import-path}
  6220. and, in some cases, @code{#:unpack-path}. The
  6221. @url{https://golang.org/doc/code.html#ImportPaths, import path}
  6222. corresponds to the file system path expected by the package's build
  6223. scripts and any referring packages, and provides a unique way to
  6224. refer to a Go package. It is typically based on a combination of the
  6225. package source code's remote URI and file system hierarchy structure. In
  6226. some cases, you will need to unpack the package's source code to a
  6227. different directory structure than the one indicated by the import path,
  6228. and @code{#:unpack-path} should be used in such cases.
  6229. Packages that provide Go libraries should install their source code into
  6230. the built output. The key @code{#:install-source?}, which defaults to
  6231. @code{#t}, controls whether or not the source code is installed. It can
  6232. be set to @code{#f} for packages that only provide executable files.
  6233. @end defvr
  6234. @defvr {Scheme Variable} glib-or-gtk-build-system
  6235. This variable is exported by @code{(guix build-system glib-or-gtk)}. It
  6236. is intended for use with packages making use of GLib or GTK+.
  6237. This build system adds the following two phases to the ones defined by
  6238. @code{gnu-build-system}:
  6239. @table @code
  6240. @item glib-or-gtk-wrap
  6241. The phase @code{glib-or-gtk-wrap} ensures that programs in
  6242. @file{bin/} are able to find GLib ``schemas'' and
  6243. @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
  6244. modules}. This is achieved by wrapping the programs in launch scripts
  6245. that appropriately set the @env{XDG_DATA_DIRS} and @env{GTK_PATH}
  6246. environment variables.
  6247. It is possible to exclude specific package outputs from that wrapping
  6248. process by listing their names in the
  6249. @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
  6250. when an output is known not to contain any GLib or GTK+ binaries, and
  6251. where wrapping would gratuitously add a dependency of that output on
  6252. GLib and GTK+.
  6253. @item glib-or-gtk-compile-schemas
  6254. The phase @code{glib-or-gtk-compile-schemas} makes sure that all
  6255. @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
  6256. GSettings schemas} of GLib are compiled. Compilation is performed by the
  6257. @command{glib-compile-schemas} program. It is provided by the package
  6258. @code{glib:bin} which is automatically imported by the build system.
  6259. The @code{glib} package providing @command{glib-compile-schemas} can be
  6260. specified with the @code{#:glib} parameter.
  6261. @end table
  6262. Both phases are executed after the @code{install} phase.
  6263. @end defvr
  6264. @defvr {Scheme Variable} guile-build-system
  6265. This build system is for Guile packages that consist exclusively of Scheme
  6266. code and that are so lean that they don't even have a makefile, let alone a
  6267. @file{configure} script. It compiles Scheme code using @command{guild
  6268. compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
  6269. installs the @file{.scm} and @file{.go} files in the right place. It also
  6270. installs documentation.
  6271. This build system supports cross-compilation by using the
  6272. @option{--target} option of @samp{guild compile}.
  6273. Packages built with @code{guile-build-system} must provide a Guile package in
  6274. their @code{native-inputs} field.
  6275. @end defvr
  6276. @defvr {Scheme Variable} julia-build-system
  6277. This variable is exported by @code{(guix build-system julia)}. It
  6278. implements the build procedure used by @uref{https://julialang.org/,
  6279. julia} packages, which essentially is similar to running @samp{julia -e
  6280. 'using Pkg; Pkg.add(package)'} in an environment where
  6281. @env{JULIA_LOAD_PATH} contains the paths to all Julia package inputs.
  6282. Tests are run by calling @code{/test/runtests.jl}.
  6283. The Julia package name is read from the file @file{Project.toml}. This
  6284. value can be overridden by passing the argument @code{#:julia-package-name}
  6285. (which must be correctly capitalized).
  6286. Julia packages usually manage they binary dependencies via
  6287. @code{JLLWrappers.jl}, a Julia package that creates a module (named
  6288. after the wrapped library followed by @code{_jll.jl}.
  6289. To add the binary path @code{_jll.jl} packages, you need to patch the
  6290. files under @file{src/wrappers/}, replacing the call to the macro
  6291. @code{JLLWrappers.@@generate_wrapper_header}, adding as a secound
  6292. argument containing the store path the binary.
  6293. As an example, in the MbedTLS Julia package, we add a build phase
  6294. (@pxref{Build Phases}) to insert the absolute file name of the wrapped
  6295. MbedTLS package:
  6296. @lisp
  6297. (add-after 'unpack 'override-binary-path
  6298. (lambda* (#:key inputs #:allow-other-keys)
  6299. (for-each (lambda (wrapper)
  6300. (substitute* wrapper
  6301. (("generate_wrapper_header.*")
  6302. (string-append
  6303. "generate_wrapper_header(\"MbedTLS\", \""
  6304. (assoc-ref inputs "mbedtls-apache") "\")\n"))))
  6305. ;; There's a Julia file for each platform, override them all.
  6306. (find-files "src/wrappers/" "\\.jl$"))))
  6307. @end lisp
  6308. Some older packages that aren't using @file{Package.toml} yet, will require
  6309. this file to be created, too. The function @code{julia-create-package-toml}
  6310. helps creating the file. You need to pass the outputs and the source of the
  6311. package, it's name (the same as the @code{file-name} parameter), the package
  6312. uuid, the package version, and a list of dependencies specified by their name
  6313. and their uuid.
  6314. @end defvr
  6315. @defvr {Scheme Variable} maven-build-system
  6316. This variable is exported by @code{(guix build-system maven)}. It implements
  6317. a build procedure for @uref{https://maven.apache.org, Maven} packages. Maven
  6318. is a dependency and lifecycle management tool for Java. A user of Maven
  6319. specifies dependencies and plugins in a @file{pom.xml} file that Maven reads.
  6320. When Maven does not have one of the dependencies or plugins in its repository,
  6321. it will download them and use them to build the package.
  6322. The maven build system ensures that maven will not try to download any
  6323. dependency by running in offline mode. Maven will fail if a dependency is
  6324. missing. Before running Maven, the @file{pom.xml} (and subprojects) are
  6325. modified to specify the version of dependencies and plugins that match the
  6326. versions available in the guix build environment. Dependencies and plugins
  6327. must be installed in the fake maven repository at @file{lib/m2}, and are
  6328. symlinked into a proper repository before maven is run. Maven is instructed
  6329. to use that repository for the build and installs built artifacts there.
  6330. Changed files are copied to the @file{lib/m2} directory of the package output.
  6331. You can specify a @file{pom.xml} file with the @code{#:pom-file} argument,
  6332. or let the build system use the default @file{pom.xml} file in the sources.
  6333. In case you need to specify a dependency's version manually, you can use the
  6334. @code{#:local-packages} argument. It takes an association list where the key
  6335. is the groupId of the package and its value is an association list where the
  6336. key is the artifactId of the package and its value is the version you want to
  6337. override in the @file{pom.xml}.
  6338. Some packages use dependencies or plugins that are not useful at runtime nor
  6339. at build time in Guix. You can alter the @file{pom.xml} file to remove them
  6340. using the @code{#:exclude} argument. Its value is an association list where
  6341. the key is the groupId of the plugin or dependency you want to remove, and
  6342. the value is a list of artifactId you want to remove.
  6343. You can override the default @code{jdk} and @code{maven} packages with the
  6344. corresponding argument, @code{#:jdk} and @code{#:maven}.
  6345. The @code{#:maven-plugins} argument is a list of maven plugins used during
  6346. the build, with the same format as the @code{inputs} fields of the package
  6347. declaration. Its default value is @code{(default-maven-plugins)} which is
  6348. also exported.
  6349. @end defvr
  6350. @defvr {Scheme Variable} minify-build-system
  6351. This variable is exported by @code{(guix build-system minify)}. It
  6352. implements a minification procedure for simple JavaScript packages.
  6353. It adds @code{uglify-js} to the set of inputs and uses it to compress
  6354. all JavaScript files in the @file{src} directory. A different minifier
  6355. package can be specified with the @code{#:uglify-js} parameter, but it
  6356. is expected that the package writes the minified code to the standard
  6357. output.
  6358. When the input JavaScript files are not all located in the @file{src}
  6359. directory, the parameter @code{#:javascript-files} can be used to
  6360. specify a list of file names to feed to the minifier.
  6361. @end defvr
  6362. @defvr {Scheme Variable} ocaml-build-system
  6363. This variable is exported by @code{(guix build-system ocaml)}. It implements
  6364. a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
  6365. of choosing the correct set of commands to run for each package. OCaml
  6366. packages can expect many different commands to be run. This build system will
  6367. try some of them.
  6368. When the package has a @file{setup.ml} file present at the top-level, it will
  6369. run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
  6370. @code{ocaml setup.ml -install}. The build system will assume that this file
  6371. was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
  6372. care of setting the prefix and enabling tests if they are not disabled. You
  6373. can pass configure and build flags with the @code{#:configure-flags} and
  6374. @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
  6375. set of flags used to enable tests. The @code{#:use-make?} key can be used to
  6376. bypass this system in the build and install phases.
  6377. When the package has a @file{configure} file, it is assumed that it is a
  6378. hand-made configure script that requires a different argument format than
  6379. in the @code{gnu-build-system}. You can add more flags with the
  6380. @code{#:configure-flags} key.
  6381. When the package has a @file{Makefile} file (or @code{#:use-make?} is
  6382. @code{#t}), it will be used and more flags can be passed to the build and
  6383. install phases with the @code{#:make-flags} key.
  6384. Finally, some packages do not have these files and use a somewhat standard
  6385. location for its build system. In that case, the build system will run
  6386. @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
  6387. providing the path to the required findlib module. Additional flags can
  6388. be passed via the @code{#:build-flags} key. Install is taken care of by
  6389. @command{opam-installer}. In this case, the @code{opam} package must
  6390. be added to the @code{native-inputs} field of the package definition.
  6391. Note that most OCaml packages assume they will be installed in the same
  6392. directory as OCaml, which is not what we want in guix. In particular, they
  6393. will install @file{.so} files in their module's directory, which is usually
  6394. fine because it is in the OCaml compiler directory. In guix though, these
  6395. libraries cannot be found and we use @env{CAML_LD_LIBRARY_PATH}. This
  6396. variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
  6397. @file{.so} libraries should be installed.
  6398. @end defvr
  6399. @defvr {Scheme Variable} python-build-system
  6400. This variable is exported by @code{(guix build-system python)}. It
  6401. implements the more or less standard build procedure used by Python
  6402. packages, which consists in running @code{python setup.py build} and
  6403. then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
  6404. For packages that install stand-alone Python programs under @code{bin/},
  6405. it takes care of wrapping these programs so that their @env{PYTHONPATH}
  6406. environment variable points to all the Python libraries they depend on.
  6407. Which Python package is used to perform the build can be specified with
  6408. the @code{#:python} parameter. This is a useful way to force a package
  6409. to be built for a specific version of the Python interpreter, which
  6410. might be necessary if the package is only compatible with a single
  6411. interpreter version.
  6412. By default guix calls @code{setup.py} under control of
  6413. @code{setuptools}, much like @command{pip} does. Some packages are not
  6414. compatible with setuptools (and pip), thus you can disable this by
  6415. setting the @code{#:use-setuptools?} parameter to @code{#f}.
  6416. @end defvr
  6417. @defvr {Scheme Variable} perl-build-system
  6418. This variable is exported by @code{(guix build-system perl)}. It
  6419. implements the standard build procedure for Perl packages, which either
  6420. consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
  6421. followed by @code{Build} and @code{Build install}; or in running
  6422. @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
  6423. @code{make} and @code{make install}, depending on which of
  6424. @code{Build.PL} or @code{Makefile.PL} is present in the package
  6425. distribution. Preference is given to the former if both @code{Build.PL}
  6426. and @code{Makefile.PL} exist in the package distribution. This
  6427. preference can be reversed by specifying @code{#t} for the
  6428. @code{#:make-maker?} parameter.
  6429. The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
  6430. passes flags specified by the @code{#:make-maker-flags} or
  6431. @code{#:module-build-flags} parameter, respectively.
  6432. Which Perl package is used can be specified with @code{#:perl}.
  6433. @end defvr
  6434. @defvr {Scheme Variable} renpy-build-system
  6435. This variable is exported by @code{(guix build-system renpy)}. It implements
  6436. the more or less standard build procedure used by Ren'py games, which consists
  6437. of loading @code{#:game} once, thereby creating bytecode for it.
  6438. It further creates a wrapper script in @code{bin/} and a desktop entry in
  6439. @code{share/applications}, both of which can be used to launch the game.
  6440. Which Ren'py package is used can be specified with @code{#:renpy}.
  6441. Games can also be installed in outputs other than ``out'' by using
  6442. @code{#:output}.
  6443. @end defvr
  6444. @defvr {Scheme Variable} qt-build-system
  6445. This variable is exported by @code{(guix build-system qt)}. It
  6446. is intended for use with applications using Qt or KDE.
  6447. This build system adds the following two phases to the ones defined by
  6448. @code{cmake-build-system}:
  6449. @table @code
  6450. @item check-setup
  6451. The phase @code{check-setup} prepares the environment for running
  6452. the checks as commonly used by Qt test programs.
  6453. For now this only sets some environment variables:
  6454. @code{QT_QPA_PLATFORM=offscreen},
  6455. @code{DBUS_FATAL_WARNINGS=0} and
  6456. @code{CTEST_OUTPUT_ON_FAILURE=1}.
  6457. This phase is added before the @code{check} phase.
  6458. It's a separate phase to ease adjusting if necessary.
  6459. @item qt-wrap
  6460. The phase @code{qt-wrap}
  6461. searches for Qt5 plugin paths, QML paths and some XDG in the inputs
  6462. and output. In case some path is found, all programs in the output's
  6463. @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
  6464. are wrapped in scripts defining the necessary environment variables.
  6465. It is possible to exclude specific package outputs from that wrapping process
  6466. by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
  6467. This is useful when an output is known not to contain any Qt binaries, and
  6468. where wrapping would gratuitously add a dependency of that output on Qt, KDE,
  6469. or such.
  6470. This phase is added after the @code{install} phase.
  6471. @end table
  6472. @end defvr
  6473. @defvr {Scheme Variable} r-build-system
  6474. This variable is exported by @code{(guix build-system r)}. It
  6475. implements the build procedure used by @uref{https://r-project.org, R}
  6476. packages, which essentially is little more than running @samp{R CMD
  6477. INSTALL --library=/gnu/store/@dots{}} in an environment where
  6478. @env{R_LIBS_SITE} contains the paths to all R package inputs. Tests are
  6479. run after installation using the R function
  6480. @code{tools::testInstalledPackage}.
  6481. @end defvr
  6482. @defvr {Scheme Variable} rakudo-build-system
  6483. This variable is exported by @code{(guix build-system rakudo)}. It
  6484. implements the build procedure used by @uref{https://rakudo.org/,
  6485. Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
  6486. package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
  6487. installs the binaries, library files and the resources, as well as wrap
  6488. the files under the @code{bin/} directory. Tests can be skipped by
  6489. passing @code{#f} to the @code{tests?} parameter.
  6490. Which rakudo package is used can be specified with @code{rakudo}.
  6491. Which perl6-tap-harness package used for the tests can be specified with
  6492. @code{#:prove6} or removed by passing @code{#f} to the
  6493. @code{with-prove6?} parameter.
  6494. Which perl6-zef package used for tests and installing can be specified
  6495. with @code{#:zef} or removed by passing @code{#f} to the
  6496. @code{with-zef?} parameter.
  6497. @end defvr
  6498. @defvr {Scheme Variable} texlive-build-system
  6499. This variable is exported by @code{(guix build-system texlive)}. It is
  6500. used to build TeX packages in batch mode with a specified engine. The
  6501. build system sets the @env{TEXINPUTS} variable to find all TeX source
  6502. files in the inputs.
  6503. By default it runs @code{luatex} on all files ending on @code{ins}. A
  6504. different engine and format can be specified with the
  6505. @code{#:tex-format} argument. Different build targets can be specified
  6506. with the @code{#:build-targets} argument, which expects a list of file
  6507. names. The build system adds only @code{texlive-bin} and
  6508. @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
  6509. inputs. Both can be overridden with the arguments @code{#:texlive-bin}
  6510. and @code{#:texlive-latex-base}, respectively.
  6511. The @code{#:tex-directory} parameter tells the build system where to
  6512. install the built files under the texmf tree.
  6513. @end defvr
  6514. @defvr {Scheme Variable} ruby-build-system
  6515. This variable is exported by @code{(guix build-system ruby)}. It
  6516. implements the RubyGems build procedure used by Ruby packages, which
  6517. involves running @code{gem build} followed by @code{gem install}.
  6518. The @code{source} field of a package that uses this build system
  6519. typically references a gem archive, since this is the format that Ruby
  6520. developers use when releasing their software. The build system unpacks
  6521. the gem archive, potentially patches the source, runs the test suite,
  6522. repackages the gem, and installs it. Additionally, directories and
  6523. tarballs may be referenced to allow building unreleased gems from Git or
  6524. a traditional source release tarball.
  6525. Which Ruby package is used can be specified with the @code{#:ruby}
  6526. parameter. A list of additional flags to be passed to the @command{gem}
  6527. command can be specified with the @code{#:gem-flags} parameter.
  6528. @end defvr
  6529. @defvr {Scheme Variable} waf-build-system
  6530. This variable is exported by @code{(guix build-system waf)}. It
  6531. implements a build procedure around the @code{waf} script. The common
  6532. phases---@code{configure}, @code{build}, and @code{install}---are
  6533. implemented by passing their names as arguments to the @code{waf}
  6534. script.
  6535. The @code{waf} script is executed by the Python interpreter. Which
  6536. Python package is used to run the script can be specified with the
  6537. @code{#:python} parameter.
  6538. @end defvr
  6539. @defvr {Scheme Variable} scons-build-system
  6540. This variable is exported by @code{(guix build-system scons)}. It
  6541. implements the build procedure used by the SCons software construction
  6542. tool. This build system runs @code{scons} to build the package,
  6543. @code{scons test} to run tests, and then @code{scons install} to install
  6544. the package.
  6545. Additional flags to be passed to @code{scons} can be specified with the
  6546. @code{#:scons-flags} parameter. The default build and install targets
  6547. can be overridden with @code{#:build-targets} and
  6548. @code{#:install-targets} respectively. The version of Python used to
  6549. run SCons can be specified by selecting the appropriate SCons package
  6550. with the @code{#:scons} parameter.
  6551. @end defvr
  6552. @defvr {Scheme Variable} haskell-build-system
  6553. This variable is exported by @code{(guix build-system haskell)}. It
  6554. implements the Cabal build procedure used by Haskell packages, which
  6555. involves running @code{runhaskell Setup.hs configure
  6556. --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
  6557. Instead of installing the package by running @code{runhaskell Setup.hs
  6558. install}, to avoid trying to register libraries in the read-only
  6559. compiler store directory, the build system uses @code{runhaskell
  6560. Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
  6561. addition, the build system generates the package documentation by
  6562. running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
  6563. is passed. Optional Haddock parameters can be passed with the help of
  6564. the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
  6565. not found, the build system looks for @code{Setup.lhs} instead.
  6566. Which Haskell compiler is used can be specified with the @code{#:haskell}
  6567. parameter which defaults to @code{ghc}.
  6568. @end defvr
  6569. @defvr {Scheme Variable} dub-build-system
  6570. This variable is exported by @code{(guix build-system dub)}. It
  6571. implements the Dub build procedure used by D packages, which
  6572. involves running @code{dub build} and @code{dub run}.
  6573. Installation is done by copying the files manually.
  6574. Which D compiler is used can be specified with the @code{#:ldc}
  6575. parameter which defaults to @code{ldc}.
  6576. @end defvr
  6577. @anchor{emacs-build-system}
  6578. @defvr {Scheme Variable} emacs-build-system
  6579. This variable is exported by @code{(guix build-system emacs)}. It
  6580. implements an installation procedure similar to the packaging system
  6581. of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
  6582. It first creates the @code{@code{package}-autoloads.el} file, then it
  6583. byte compiles all Emacs Lisp files. Differently from the Emacs
  6584. packaging system, the Info documentation files are moved to the standard
  6585. documentation directory and the @file{dir} file is deleted. The Elisp
  6586. package files are installed directly under @file{share/emacs/site-lisp}.
  6587. @end defvr
  6588. @defvr {Scheme Variable} font-build-system
  6589. This variable is exported by @code{(guix build-system font)}. It
  6590. implements an installation procedure for font packages where upstream
  6591. provides pre-compiled TrueType, OpenType, etc.@: font files that merely
  6592. need to be copied into place. It copies font files to standard
  6593. locations in the output directory.
  6594. @end defvr
  6595. @defvr {Scheme Variable} meson-build-system
  6596. This variable is exported by @code{(guix build-system meson)}. It
  6597. implements the build procedure for packages that use
  6598. @url{https://mesonbuild.com, Meson} as their build system.
  6599. It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
  6600. of inputs, and they can be changed with the parameters @code{#:meson}
  6601. and @code{#:ninja} if needed. The default Meson is
  6602. @code{meson-for-build}, which is special because it doesn't clear the
  6603. @code{RUNPATH} of binaries and libraries when they are installed.
  6604. This build system is an extension of @code{gnu-build-system}, but with the
  6605. following phases changed to some specific for Meson:
  6606. @table @code
  6607. @item configure
  6608. The phase runs @code{meson} with the flags specified in
  6609. @code{#:configure-flags}. The flag @option{--buildtype} is always set to
  6610. @code{debugoptimized} unless something else is specified in
  6611. @code{#:build-type}.
  6612. @item build
  6613. The phase runs @code{ninja} to build the package in parallel by default, but
  6614. this can be changed with @code{#:parallel-build?}.
  6615. @item check
  6616. The phase runs @code{ninja} with the target specified in @code{#:test-target},
  6617. which is @code{"test"} by default.
  6618. @item install
  6619. The phase runs @code{ninja install} and can not be changed.
  6620. @end table
  6621. Apart from that, the build system also adds the following phases:
  6622. @table @code
  6623. @item fix-runpath
  6624. This phase ensures that all binaries can find the libraries they need.
  6625. It searches for required libraries in subdirectories of the package being
  6626. built, and adds those to @code{RUNPATH} where needed. It also removes
  6627. references to libraries left over from the build phase by
  6628. @code{meson-for-build}, such as test dependencies, that aren't actually
  6629. required for the program to run.
  6630. @item glib-or-gtk-wrap
  6631. This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
  6632. is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
  6633. @item glib-or-gtk-compile-schemas
  6634. This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
  6635. is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
  6636. @end table
  6637. @end defvr
  6638. @defvr {Scheme Variable} linux-module-build-system
  6639. @code{linux-module-build-system} allows building Linux kernel modules.
  6640. @cindex build phases
  6641. This build system is an extension of @code{gnu-build-system}, but with the
  6642. following phases changed:
  6643. @table @code
  6644. @item configure
  6645. This phase configures the environment so that the Linux kernel's Makefile
  6646. can be used to build the external kernel module.
  6647. @item build
  6648. This phase uses the Linux kernel's Makefile in order to build the external
  6649. kernel module.
  6650. @item install
  6651. This phase uses the Linux kernel's Makefile in order to install the external
  6652. kernel module.
  6653. @end table
  6654. It is possible and useful to specify the Linux kernel to use for building
  6655. the module (in the @code{arguments} form of a package using the
  6656. @code{linux-module-build-system}, use the key @code{#:linux} to specify it).
  6657. @end defvr
  6658. @defvr {Scheme Variable} node-build-system
  6659. This variable is exported by @code{(guix build-system node)}. It
  6660. implements the build procedure used by @uref{https://nodejs.org,
  6661. Node.js}, which implements an approximation of the @code{npm install}
  6662. command, followed by an @code{npm test} command.
  6663. Which Node.js package is used to interpret the @code{npm} commands can
  6664. be specified with the @code{#:node} parameter which defaults to
  6665. @code{node}.
  6666. @end defvr
  6667. Lastly, for packages that do not need anything as sophisticated, a
  6668. ``trivial'' build system is provided. It is trivial in the sense that
  6669. it provides basically no support: it does not pull any implicit inputs,
  6670. and does not have a notion of build phases.
  6671. @defvr {Scheme Variable} trivial-build-system
  6672. This variable is exported by @code{(guix build-system trivial)}.
  6673. This build system requires a @code{#:builder} argument. This argument
  6674. must be a Scheme expression that builds the package output(s)---as
  6675. with @code{build-expression->derivation} (@pxref{Derivations,
  6676. @code{build-expression->derivation}}).
  6677. @end defvr
  6678. @node Build Phases
  6679. @section Build Phases
  6680. @cindex build phases, for packages
  6681. Almost all package build systems implement a notion @dfn{build phases}:
  6682. a sequence of actions that the build system executes, when you build the
  6683. package, leading to the installed byproducts in the store. A notable
  6684. exception is the ``bare-bones'' @code{trivial-build-system}
  6685. (@pxref{Build Systems}).
  6686. As discussed in the previous section, those build systems provide a
  6687. standard list of phases. For @code{gnu-build-system}, the standard
  6688. phases include an @code{unpack} phase to unpack the source code tarball,
  6689. a @command{configure} phase to run @code{./configure}, a @code{build}
  6690. phase to run @command{make}, and (among others) an @code{install} phase
  6691. to run @command{make install}; @pxref{Build Systems}, for a more
  6692. detailed view of these phases. Likewise, @code{cmake-build-system}
  6693. inherits these phases, but its @code{configure} phase runs
  6694. @command{cmake} instead of @command{./configure}. Other build systems,
  6695. such as @code{python-build-system}, have a wholly different list of
  6696. standard phases. All this code runs on the @dfn{build side}: it is
  6697. evaluated when you actually build the package, in a dedicated build
  6698. process spawned by the build daemon (@pxref{Invoking guix-daemon}).
  6699. Build phases are represented as association lists or ``alists''
  6700. (@pxref{Association Lists,,, guile, GNU Guile Reference Manual}) where
  6701. each key is a symbol for the name of the phase and the associated value
  6702. is a procedure that accepts an arbitrary number of arguments. By
  6703. convention, those procedures receive information about the build in the
  6704. form of @dfn{keyword parameters}, which they can use or ignore.
  6705. For example, here is how @code{(guix build gnu-build-system)} defines
  6706. @code{%standard-phases}, the variable holding its alist of build
  6707. phases@footnote{We present a simplified view of those build phases, but
  6708. do take a look at @code{(guix build gnu-build-system)} to see all the
  6709. details!}:
  6710. @lisp
  6711. ;; The build phases of 'gnu-build-system'.
  6712. (define* (unpack #:key source #:allow-other-keys)
  6713. ;; Extract the source tarball.
  6714. (invoke "tar" "xvf" source))
  6715. (define* (configure #:key outputs #:allow-other-keys)
  6716. ;; Run the 'configure' script. Install to output "out".
  6717. (let ((out (assoc-ref outputs "out")))
  6718. (invoke "./configure"
  6719. (string-append "--prefix=" out))))
  6720. (define* (build #:allow-other-keys)
  6721. ;; Compile.
  6722. (invoke "make"))
  6723. (define* (check #:key (test-target "check") (tests? #true)
  6724. #:allow-other-keys)
  6725. ;; Run the test suite.
  6726. (if tests?
  6727. (invoke "make" test-target)
  6728. (display "test suite not run\n")))
  6729. (define* (install #:allow-other-keys)
  6730. ;; Install files to the prefix 'configure' specified.
  6731. (invoke "make" "install"))
  6732. (define %standard-phases
  6733. ;; The list of standard phases (quite a few are omitted
  6734. ;; for brevity). Each element is a symbol/procedure pair.
  6735. (list (cons 'unpack unpack)
  6736. (cons 'configure configure)
  6737. (cons 'build build)
  6738. (cons 'check check)
  6739. (cons 'install install)))
  6740. @end lisp
  6741. This shows how @code{%standard-phases} is defined as a list of
  6742. symbol/procedure pairs (@pxref{Pairs,,, guile, GNU Guile Reference
  6743. Manual}). The first pair associates the @code{unpack} procedure with
  6744. the @code{unpack} symbol---a name; the second pair defines the
  6745. @code{configure} phase similarly, and so on. When building a package
  6746. that uses @code{gnu-build-system} with its default list of phases, those
  6747. phases are executed sequentially. You can see the name of each phase
  6748. started and completed in the build log of packages that you build.
  6749. Let's now look at the procedures themselves. Each one is defined with
  6750. @code{define*}: @code{#:key} lists keyword parameters the procedure
  6751. accepts, possibly with a default value, and @code{#:allow-other-keys}
  6752. specifies that other keyword parameters are ignored (@pxref{Optional
  6753. Arguments,,, guile, GNU Guile Reference Manual}).
  6754. The @code{unpack} procedure honors the @code{source} parameter, which
  6755. the build system uses to pass the file name of the source tarball (or
  6756. version control checkout), and it ignores other parameters. The
  6757. @code{configure} phase only cares about the @code{outputs} parameter, an
  6758. alist mapping package output names to their store file name
  6759. (@pxref{Packages with Multiple Outputs}). It extracts the file name of
  6760. for @code{out}, the default output, and passes it to
  6761. @command{./configure} as the installation prefix, meaning that
  6762. @command{make install} will eventually copy all the files in that
  6763. directory (@pxref{Configuration, configuration and makefile
  6764. conventions,, standards, GNU Coding Standards}). @code{build} and
  6765. @code{install} ignore all their arguments. @code{check} honors the
  6766. @code{test-target} argument, which specifies the name of the Makefile
  6767. target to run tests; it prints a message and skips tests when
  6768. @code{tests?} is false.
  6769. @cindex build phases, customizing
  6770. The list of phases used for a particular package can be changed with the
  6771. @code{#:phases} parameter of the build system. Changing the set of
  6772. build phases boils down to building a new alist of phases based on the
  6773. @code{%standard-phases} alist described above. This can be done with
  6774. standard alist procedures such as @code{alist-delete} (@pxref{SRFI-1
  6775. Association Lists,,, guile, GNU Guile Reference Manual}); however, it is
  6776. more convenient to do so with @code{modify-phases} (@pxref{Build
  6777. Utilities, @code{modify-phases}}).
  6778. Here is an example of a package definition that removes the
  6779. @code{configure} phase of @code{%standard-phases} and inserts a new
  6780. phase before the @code{build} phase, called
  6781. @code{set-prefix-in-makefile}:
  6782. @lisp
  6783. (define-public example
  6784. (package
  6785. (name "example")
  6786. ;; other fields omitted
  6787. (build-system gnu-build-system)
  6788. (arguments
  6789. '(#:phases (modify-phases %standard-phases
  6790. (delete 'configure)
  6791. (add-before 'build 'set-prefix-in-makefile
  6792. (lambda* (#:key outputs #:allow-other-keys)
  6793. ;; Modify the makefile so that its
  6794. ;; 'PREFIX' variable points to "out".
  6795. (let ((out (assoc-ref outputs "out")))
  6796. (substitute* "Makefile"
  6797. (("PREFIX =.*")
  6798. (string-append "PREFIX = "
  6799. out "\n")))
  6800. #true))))))))
  6801. @end lisp
  6802. The new phase that is inserted is written as an anonymous procedure,
  6803. introduced with @code{lambda*}; it honors the @code{outputs} parameter
  6804. we have seen before. @xref{Build Utilities}, for more about the helpers
  6805. used by this phase, and for more examples of @code{modify-phases}.
  6806. @cindex code staging
  6807. @cindex staging, of code
  6808. Keep in mind that build phases are code evaluated at the time the
  6809. package is actually built. This explains why the whole
  6810. @code{modify-phases} expression above is quoted (it comes after the
  6811. @code{'} or apostrophe): it is @dfn{staged} for later execution.
  6812. @xref{G-Expressions}, for an explanation of code staging and the
  6813. @dfn{code strata} involved.
  6814. @node Build Utilities
  6815. @section Build Utilities
  6816. As soon as you start writing non-trivial package definitions
  6817. (@pxref{Defining Packages}) or other build actions
  6818. (@pxref{G-Expressions}), you will likely start looking for helpers for
  6819. ``shell-like'' actions---creating directories, copying and deleting
  6820. files recursively, manipulating build phases, and so on. The
  6821. @code{(guix build utils)} module provides such utility procedures.
  6822. Most build systems load @code{(guix build utils)} (@pxref{Build
  6823. Systems}). Thus, when writing custom build phases for your package
  6824. definitions, you can usually assume those procedures are in scope.
  6825. When writing G-expressions, you can import @code{(guix build utils)} on
  6826. the ``build side'' using @code{with-imported-modules} and then put it in
  6827. scope with the @code{use-modules} form (@pxref{Using Guile Modules,,,
  6828. guile, GNU Guile Reference Manual}):
  6829. @lisp
  6830. (with-imported-modules '((guix build utils)) ;import it
  6831. (computed-file "empty-tree"
  6832. #~(begin
  6833. ;; Put it in scope.
  6834. (use-modules (guix build utils))
  6835. ;; Happily use its 'mkdir-p' procedure.
  6836. (mkdir-p (string-append #$output "/a/b/c")))))
  6837. @end lisp
  6838. The remainder of this section is the reference for most of the utility
  6839. procedures provided by @code{(guix build utils)}.
  6840. @c TODO Document what's missing.
  6841. @subsection Dealing with Store File Names
  6842. This section documents procedures that deal with store file names.
  6843. @deffn {Scheme Procedure} %store-directory
  6844. Return the directory name of the store.
  6845. @end deffn
  6846. @deffn {Scheme Procedure} store-file-name? @var{file}
  6847. Return true if @var{file} is in the store.
  6848. @end deffn
  6849. @deffn {Scheme Procedure} strip-store-file-name @var{file}
  6850. Strip the @file{/gnu/store} and hash from @var{file}, a store file name.
  6851. The result is typically a @code{"@var{package}-@var{version}"} string.
  6852. @end deffn
  6853. @deffn {Scheme Procedure} package-name->name+version @var{name}
  6854. Given @var{name}, a package name like @code{"foo-0.9.1b"}, return two
  6855. values: @code{"foo"} and @code{"0.9.1b"}. When the version part is
  6856. unavailable, @var{name} and @code{#f} are returned. The first hyphen
  6857. followed by a digit is considered to introduce the version part.
  6858. @end deffn
  6859. @subsection File Types
  6860. The procedures below deal with files and file types.
  6861. @deffn {Scheme Procedure} directory-exists? @var{dir}
  6862. Return @code{#t} if @var{dir} exists and is a directory.
  6863. @end deffn
  6864. @deffn {Scheme Procedure} executable-file? @var{file}
  6865. Return @code{#t} if @var{file} exists and is executable.
  6866. @end deffn
  6867. @deffn {Scheme Procedure} symbolic-link? @var{file}
  6868. Return @code{#t} if @var{file} is a symbolic link (aka. a ``symlink'').
  6869. @end deffn
  6870. @deffn {Scheme Procedure} elf-file? @var{file}
  6871. @deffnx {Scheme Procedure} ar-file? @var{file}
  6872. @deffnx {Scheme Procedure} gzip-file? @var{file}
  6873. Return @code{#t} if @var{file} is, respectively, an ELF file, an
  6874. @code{ar} archive (such as a @file{.a} static library), or a gzip file.
  6875. @end deffn
  6876. @deffn {Scheme Procedure} reset-gzip-timestamp @var{file} [#:keep-mtime? #t]
  6877. If @var{file} is a gzip file, reset its embedded timestamp (as with
  6878. @command{gzip --no-name}) and return true. Otherwise return @code{#f}.
  6879. When @var{keep-mtime?} is true, preserve @var{file}'s modification time.
  6880. @end deffn
  6881. @subsection File Manipulation
  6882. The following procedures and macros help create, modify, and delete
  6883. files. They provide functionality comparable to common shell utilities
  6884. such as @command{mkdir -p}, @command{cp -r}, @command{rm -r}, and
  6885. @command{sed}. They complement Guile's extensive, but low-level, file
  6886. system interface (@pxref{POSIX,,, guile, GNU Guile Reference Manual}).
  6887. @deffn {Scheme Syntax} with-directory-excursion @var{directory} @var{body}@dots{}
  6888. Run @var{body} with @var{directory} as the process's current directory.
  6889. Essentially, this macro changes the current directory to @var{directory}
  6890. before evaluating @var{body}, using @code{chdir} (@pxref{Processes,,,
  6891. guile, GNU Guile Reference Manual}). It changes back to the initial
  6892. directory when the dynamic extent of @var{body} is left, be it @i{via}
  6893. normal procedure return or @i{via} a non-local exit such as an
  6894. exception.
  6895. @end deffn
  6896. @deffn {Scheme Procedure} mkdir-p @var{dir}
  6897. Create directory @var{dir} and all its ancestors.
  6898. @end deffn
  6899. @deffn {Scheme Procedure} install-file @var{file} @var{directory}
  6900. Create @var{directory} if it does not exist and copy @var{file} in there
  6901. under the same name.
  6902. @end deffn
  6903. @deffn {Scheme Procedure} make-file-writable @var{file}
  6904. Make @var{file} writable for its owner.
  6905. @end deffn
  6906. @deffn {Scheme Procedure} copy-recursively @var{source} @var{destination} @
  6907. [#:log (current-output-port)] [#:follow-symlinks? #f] [#:keep-mtime? #f]
  6908. Copy @var{source} directory to @var{destination}. Follow symlinks if
  6909. @var{follow-symlinks?} is true; otherwise, just preserve them. When
  6910. @var{keep-mtime?} is true, keep the modification time of the files in
  6911. @var{source} on those of @var{destination}. Write verbose output to the
  6912. @var{log} port.
  6913. @end deffn
  6914. @deffn {Scheme Procedure} delete-file-recursively @var{dir} @
  6915. [#:follow-mounts? #f]
  6916. Delete @var{dir} recursively, like @command{rm -rf}, without following
  6917. symlinks. Don't follow mount points either, unless @var{follow-mounts?}
  6918. is true. Report but ignore errors.
  6919. @end deffn
  6920. @deffn {Scheme Syntax} substitute* @var{file} @
  6921. ((@var{regexp} @var{match-var}@dots{}) @var{body}@dots{}) @dots{}
  6922. Substitute @var{regexp} in @var{file} by the string returned by
  6923. @var{body}. @var{body} is evaluated with each @var{match-var} bound to
  6924. the corresponding positional regexp sub-expression. For example:
  6925. @lisp
  6926. (substitute* file
  6927. (("hello")
  6928. "good morning\n")
  6929. (("foo([a-z]+)bar(.*)$" all letters end)
  6930. (string-append "baz" letter end)))
  6931. @end lisp
  6932. Here, anytime a line of @var{file} contains @code{hello}, it is replaced
  6933. by @code{good morning}. Anytime a line of @var{file} matches the second
  6934. regexp, @code{all} is bound to the complete match, @code{letters} is bound
  6935. to the first sub-expression, and @code{end} is bound to the last one.
  6936. When one of the @var{match-var} is @code{_}, no variable is bound to the
  6937. corresponding match substring.
  6938. Alternatively, @var{file} may be a list of file names, in which case
  6939. they are all subject to the substitutions.
  6940. Be careful about using @code{$} to match the end of a line; by itself it
  6941. won't match the terminating newline of a line.
  6942. @end deffn
  6943. @subsection File Search
  6944. @cindex file, searching
  6945. This section documents procedures to search and filter files.
  6946. @deffn {Scheme Procedure} file-name-predicate @var{regexp}
  6947. Return a predicate that returns true when passed a file name whose base
  6948. name matches @var{regexp}.
  6949. @end deffn
  6950. @deffn {Scheme Procedure} find-files @var{dir} [@var{pred}] @
  6951. [#:stat lstat] [#:directories? #f] [#:fail-on-error? #f]
  6952. Return the lexicographically sorted list of files under @var{dir} for
  6953. which @var{pred} returns true. @var{pred} is passed two arguments: the
  6954. absolute file name, and its stat buffer; the default predicate always
  6955. returns true. @var{pred} can also be a regular expression, in which
  6956. case it is equivalent to @code{(file-name-predicate @var{pred})}.
  6957. @var{stat} is used to obtain file information; using @code{lstat} means
  6958. that symlinks are not followed. If @var{directories?} is true, then
  6959. directories will also be included. If @var{fail-on-error?} is true,
  6960. raise an exception upon error.
  6961. @end deffn
  6962. Here are a few examples where we assume that the current directory is
  6963. the root of the Guix source tree:
  6964. @lisp
  6965. ;; List all the regular files in the current directory.
  6966. (find-files ".")
  6967. @result{} ("./.dir-locals.el" "./.gitignore" @dots{})
  6968. ;; List all the .scm files under gnu/services.
  6969. (find-files "gnu/services" "\\.scm$")
  6970. @result{} ("gnu/services/admin.scm" "gnu/services/audio.scm" @dots{})
  6971. ;; List ar files in the current directory.
  6972. (find-files "." (lambda (file stat) (ar-file? file)))
  6973. @result{} ("./libformat.a" "./libstore.a" @dots{})
  6974. @end lisp
  6975. @deffn {Scheme Procedure} which @var{program}
  6976. Return the complete file name for @var{program} as found in
  6977. @code{$PATH}, or @code{#f} if @var{program} could not be found.
  6978. @end deffn
  6979. @subsection Build Phases
  6980. @cindex build phases
  6981. The @code{(guix build utils)} also contains tools to manipulate build
  6982. phases as used by build systems (@pxref{Build Systems}). Build phases
  6983. are represented as association lists or ``alists'' (@pxref{Association
  6984. Lists,,, guile, GNU Guile Reference Manual}) where each key is a symbol
  6985. naming the phase and the associated value is a procedure (@pxref{Build
  6986. Phases}).
  6987. Guile core and the @code{(srfi srfi-1)} module both provide tools to
  6988. manipulate alists. The @code{(guix build utils)} module complements
  6989. those with tools written with build phases in mind.
  6990. @cindex build phases, modifying
  6991. @deffn {Scheme Syntax} modify-phases @var{phases} @var{clause}@dots{}
  6992. Modify @var{phases} sequentially as per each @var{clause}, which may
  6993. have one of the following forms:
  6994. @lisp
  6995. (delete @var{old-phase-name})
  6996. (replace @var{old-phase-name} @var{new-phase})
  6997. (add-before @var{old-phase-name} @var{new-phase-name} @var{new-phase})
  6998. (add-after @var{old-phase-name} @var{new-phase-name} @var{new-phase})
  6999. @end lisp
  7000. Where every @var{phase-name} above is an expression evaluating to a
  7001. symbol, and @var{new-phase} an expression evaluating to a procedure.
  7002. @end deffn
  7003. The example below is taken from the definition of the @code{grep}
  7004. package. It adds a phase to run after the @code{install} phase, called
  7005. @code{fix-egrep-and-fgrep}. That phase is a procedure (@code{lambda*}
  7006. is for anonymous procedures) that takes a @code{#:outputs} keyword
  7007. argument and ignores extra keyword arguments (@pxref{Optional
  7008. Arguments,,, guile, GNU Guile Reference Manual}, for more on
  7009. @code{lambda*} and optional and keyword arguments.) The phase uses
  7010. @code{substitute*} to modify the installed @file{egrep} and @file{fgrep}
  7011. scripts so that they refer to @code{grep} by its absolute file name:
  7012. @lisp
  7013. (modify-phases %standard-phases
  7014. (add-after 'install 'fix-egrep-and-fgrep
  7015. ;; Patch 'egrep' and 'fgrep' to execute 'grep' via its
  7016. ;; absolute file name instead of searching for it in $PATH.
  7017. (lambda* (#:key outputs #:allow-other-keys)
  7018. (let* ((out (assoc-ref outputs "out"))
  7019. (bin (string-append out "/bin")))
  7020. (substitute* (list (string-append bin "/egrep")
  7021. (string-append bin "/fgrep"))
  7022. (("^exec grep")
  7023. (string-append "exec " bin "/grep")))
  7024. #t))))
  7025. @end lisp
  7026. In the example below, phases are modified in two ways: the standard
  7027. @code{configure} phase is deleted, presumably because the package does
  7028. not have a @file{configure} script or anything similar, and the default
  7029. @code{install} phase is replaced by one that manually copies the
  7030. executable files to be installed:
  7031. @lisp
  7032. (modify-phases %standard-phases
  7033. (delete 'configure) ;no 'configure' script
  7034. (replace 'install
  7035. (lambda* (#:key outputs #:allow-other-keys)
  7036. ;; The package's Makefile doesn't provide an "install"
  7037. ;; rule so do it by ourselves.
  7038. (let ((bin (string-append (assoc-ref outputs "out")
  7039. "/bin")))
  7040. (install-file "footswitch" bin)
  7041. (install-file "scythe" bin)
  7042. #t))))
  7043. @end lisp
  7044. @c TODO: Add more examples.
  7045. @node The Store
  7046. @section The Store
  7047. @cindex store
  7048. @cindex store items
  7049. @cindex store paths
  7050. Conceptually, the @dfn{store} is the place where derivations that have
  7051. been built successfully are stored---by default, @file{/gnu/store}.
  7052. Sub-directories in the store are referred to as @dfn{store items} or
  7053. sometimes @dfn{store paths}. The store has an associated database that
  7054. contains information such as the store paths referred to by each store
  7055. path, and the list of @emph{valid} store items---results of successful
  7056. builds. This database resides in @file{@var{localstatedir}/guix/db},
  7057. where @var{localstatedir} is the state directory specified @i{via}
  7058. @option{--localstatedir} at configure time, usually @file{/var}.
  7059. The store is @emph{always} accessed by the daemon on behalf of its clients
  7060. (@pxref{Invoking guix-daemon}). To manipulate the store, clients
  7061. connect to the daemon over a Unix-domain socket, send requests to it,
  7062. and read the result---these are remote procedure calls, or RPCs.
  7063. @quotation Note
  7064. Users must @emph{never} modify files under @file{/gnu/store} directly.
  7065. This would lead to inconsistencies and break the immutability
  7066. assumptions of Guix's functional model (@pxref{Introduction}).
  7067. @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
  7068. how to check the integrity of the store and attempt recovery from
  7069. accidental modifications.
  7070. @end quotation
  7071. The @code{(guix store)} module provides procedures to connect to the
  7072. daemon, and to perform RPCs. These are described below. By default,
  7073. @code{open-connection}, and thus all the @command{guix} commands,
  7074. connect to the local daemon or to the URI specified by the
  7075. @env{GUIX_DAEMON_SOCKET} environment variable.
  7076. @defvr {Environment Variable} GUIX_DAEMON_SOCKET
  7077. When set, the value of this variable should be a file name or a URI
  7078. designating the daemon endpoint. When it is a file name, it denotes a
  7079. Unix-domain socket to connect to. In addition to file names, the
  7080. supported URI schemes are:
  7081. @table @code
  7082. @item file
  7083. @itemx unix
  7084. These are for Unix-domain sockets.
  7085. @code{file:///var/guix/daemon-socket/socket} is equivalent to
  7086. @file{/var/guix/daemon-socket/socket}.
  7087. @item guix
  7088. @cindex daemon, remote access
  7089. @cindex remote access to the daemon
  7090. @cindex daemon, cluster setup
  7091. @cindex clusters, daemon setup
  7092. These URIs denote connections over TCP/IP, without encryption nor
  7093. authentication of the remote host. The URI must specify the host name
  7094. and optionally a port number (by default port 44146 is used):
  7095. @example
  7096. guix://master.guix.example.org:1234
  7097. @end example
  7098. This setup is suitable on local networks, such as clusters, where only
  7099. trusted nodes may connect to the build daemon at
  7100. @code{master.guix.example.org}.
  7101. The @option{--listen} option of @command{guix-daemon} can be used to
  7102. instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
  7103. @option{--listen}}).
  7104. @item ssh
  7105. @cindex SSH access to build daemons
  7106. These URIs allow you to connect to a remote daemon over SSH@. This
  7107. feature requires Guile-SSH (@pxref{Requirements}) and a working
  7108. @command{guile} binary in @env{PATH} on the destination machine. It
  7109. supports public key and GSSAPI authentication. A typical URL might look
  7110. like this:
  7111. @example
  7112. ssh://charlie@@guix.example.org:22
  7113. @end example
  7114. As for @command{guix copy}, the usual OpenSSH client configuration files
  7115. are honored (@pxref{Invoking guix copy}).
  7116. @end table
  7117. Additional URI schemes may be supported in the future.
  7118. @c XXX: Remove this note when the protocol incurs fewer round trips
  7119. @c and when (guix derivations) no longer relies on file system access.
  7120. @quotation Note
  7121. The ability to connect to remote build daemons is considered
  7122. experimental as of @value{VERSION}. Please get in touch with us to
  7123. share any problems or suggestions you may have (@pxref{Contributing}).
  7124. @end quotation
  7125. @end defvr
  7126. @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
  7127. Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
  7128. @var{reserve-space?} is true, instruct it to reserve a little bit of
  7129. extra space on the file system so that the garbage collector can still
  7130. operate should the disk become full. Return a server object.
  7131. @var{file} defaults to @code{%default-socket-path}, which is the normal
  7132. location given the options that were passed to @command{configure}.
  7133. @end deffn
  7134. @deffn {Scheme Procedure} close-connection @var{server}
  7135. Close the connection to @var{server}.
  7136. @end deffn
  7137. @defvr {Scheme Variable} current-build-output-port
  7138. This variable is bound to a SRFI-39 parameter, which refers to the port
  7139. where build and error logs sent by the daemon should be written.
  7140. @end defvr
  7141. Procedures that make RPCs all take a server object as their first
  7142. argument.
  7143. @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
  7144. @cindex invalid store items
  7145. Return @code{#t} when @var{path} designates a valid store item and
  7146. @code{#f} otherwise (an invalid item may exist on disk but still be
  7147. invalid, for instance because it is the result of an aborted or failed
  7148. build).
  7149. A @code{&store-protocol-error} condition is raised if @var{path} is not
  7150. prefixed by the store directory (@file{/gnu/store}).
  7151. @end deffn
  7152. @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
  7153. Add @var{text} under file @var{name} in the store, and return its store
  7154. path. @var{references} is the list of store paths referred to by the
  7155. resulting store path.
  7156. @end deffn
  7157. @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
  7158. [@var{mode}]
  7159. Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
  7160. file names, or derivation/output pairs, using the specified
  7161. @var{mode}---@code{(build-mode normal)} by default.
  7162. @end deffn
  7163. Note that the @code{(guix monads)} module provides a monad as well as
  7164. monadic versions of the above procedures, with the goal of making it
  7165. more convenient to work with code that accesses the store (@pxref{The
  7166. Store Monad}).
  7167. @c FIXME
  7168. @i{This section is currently incomplete.}
  7169. @node Derivations
  7170. @section Derivations
  7171. @cindex derivations
  7172. Low-level build actions and the environment in which they are performed
  7173. are represented by @dfn{derivations}. A derivation contains the
  7174. following pieces of information:
  7175. @itemize
  7176. @item
  7177. The outputs of the derivation---derivations produce at least one file or
  7178. directory in the store, but may produce more.
  7179. @item
  7180. @cindex build-time dependencies
  7181. @cindex dependencies, build-time
  7182. The inputs of the derivations---i.e., its build-time dependencies---which may
  7183. be other derivations or plain files in the store (patches, build scripts,
  7184. etc.).
  7185. @item
  7186. The system type targeted by the derivation---e.g., @code{x86_64-linux}.
  7187. @item
  7188. The file name of a build script in the store, along with the arguments
  7189. to be passed.
  7190. @item
  7191. A list of environment variables to be defined.
  7192. @end itemize
  7193. @cindex derivation path
  7194. Derivations allow clients of the daemon to communicate build actions to
  7195. the store. They exist in two forms: as an in-memory representation,
  7196. both on the client- and daemon-side, and as files in the store whose
  7197. name end in @file{.drv}---these files are referred to as @dfn{derivation
  7198. paths}. Derivations paths can be passed to the @code{build-derivations}
  7199. procedure to perform the build actions they prescribe (@pxref{The
  7200. Store}).
  7201. @cindex fixed-output derivations
  7202. Operations such as file downloads and version-control checkouts for
  7203. which the expected content hash is known in advance are modeled as
  7204. @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
  7205. of a fixed-output derivation are independent of its inputs---e.g., a
  7206. source code download produces the same result regardless of the download
  7207. method and tools being used.
  7208. @cindex references
  7209. @cindex run-time dependencies
  7210. @cindex dependencies, run-time
  7211. The outputs of derivations---i.e., the build results---have a set of
  7212. @dfn{references}, as reported by the @code{references} RPC or the
  7213. @command{guix gc --references} command (@pxref{Invoking guix gc}). References
  7214. are the set of run-time dependencies of the build results. References are a
  7215. subset of the inputs of the derivation; this subset is automatically computed
  7216. by the build daemon by scanning all the files in the outputs.
  7217. The @code{(guix derivations)} module provides a representation of
  7218. derivations as Scheme objects, along with procedures to create and
  7219. otherwise manipulate derivations. The lowest-level primitive to create
  7220. a derivation is the @code{derivation} procedure:
  7221. @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
  7222. @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
  7223. [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
  7224. [#:system (%current-system)] [#:references-graphs #f] @
  7225. [#:allowed-references #f] [#:disallowed-references #f] @
  7226. [#:leaked-env-vars #f] [#:local-build? #f] @
  7227. [#:substitutable? #t] [#:properties '()]
  7228. Build a derivation with the given arguments, and return the resulting
  7229. @code{<derivation>} object.
  7230. When @var{hash} and @var{hash-algo} are given, a
  7231. @dfn{fixed-output derivation} is created---i.e., one whose result is
  7232. known in advance, such as a file download. If, in addition,
  7233. @var{recursive?} is true, then that fixed output may be an executable
  7234. file or a directory and @var{hash} must be the hash of an archive
  7235. containing this output.
  7236. When @var{references-graphs} is true, it must be a list of file
  7237. name/store path pairs. In that case, the reference graph of each store
  7238. path is exported in the build environment in the corresponding file, in
  7239. a simple text format.
  7240. When @var{allowed-references} is true, it must be a list of store items
  7241. or outputs that the derivation's output may refer to. Likewise,
  7242. @var{disallowed-references}, if true, must be a list of things the
  7243. outputs may @emph{not} refer to.
  7244. When @var{leaked-env-vars} is true, it must be a list of strings
  7245. denoting environment variables that are allowed to ``leak'' from the
  7246. daemon's environment to the build environment. This is only applicable
  7247. to fixed-output derivations---i.e., when @var{hash} is true. The main
  7248. use is to allow variables such as @code{http_proxy} to be passed to
  7249. derivations that download files.
  7250. When @var{local-build?} is true, declare that the derivation is not a
  7251. good candidate for offloading and should rather be built locally
  7252. (@pxref{Daemon Offload Setup}). This is the case for small derivations
  7253. where the costs of data transfers would outweigh the benefits.
  7254. When @var{substitutable?} is false, declare that substitutes of the
  7255. derivation's output should not be used (@pxref{Substitutes}). This is
  7256. useful, for instance, when building packages that capture details of the
  7257. host CPU instruction set.
  7258. @var{properties} must be an association list describing ``properties'' of the
  7259. derivation. It is kept as-is, uninterpreted, in the derivation.
  7260. @end deffn
  7261. @noindent
  7262. Here's an example with a shell script as its builder, assuming
  7263. @var{store} is an open connection to the daemon, and @var{bash} points
  7264. to a Bash executable in the store:
  7265. @lisp
  7266. (use-modules (guix utils)
  7267. (guix store)
  7268. (guix derivations))
  7269. (let ((builder ; add the Bash script to the store
  7270. (add-text-to-store store "my-builder.sh"
  7271. "echo hello world > $out\n" '())))
  7272. (derivation store "foo"
  7273. bash `("-e" ,builder)
  7274. #:inputs `((,bash) (,builder))
  7275. #:env-vars '(("HOME" . "/homeless"))))
  7276. @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
  7277. @end lisp
  7278. As can be guessed, this primitive is cumbersome to use directly. A
  7279. better approach is to write build scripts in Scheme, of course! The
  7280. best course of action for that is to write the build code as a
  7281. ``G-expression'', and to pass it to @code{gexp->derivation}. For more
  7282. information, @pxref{G-Expressions}.
  7283. Once upon a time, @code{gexp->derivation} did not exist and constructing
  7284. derivations with build code written in Scheme was achieved with
  7285. @code{build-expression->derivation}, documented below. This procedure
  7286. is now deprecated in favor of the much nicer @code{gexp->derivation}.
  7287. @deffn {Scheme Procedure} build-expression->derivation @var{store} @
  7288. @var{name} @var{exp} @
  7289. [#:system (%current-system)] [#:inputs '()] @
  7290. [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
  7291. [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
  7292. [#:references-graphs #f] [#:allowed-references #f] @
  7293. [#:disallowed-references #f] @
  7294. [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
  7295. Return a derivation that executes Scheme expression @var{exp} as a
  7296. builder for derivation @var{name}. @var{inputs} must be a list of
  7297. @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
  7298. @code{"out"} is assumed. @var{modules} is a list of names of Guile
  7299. modules from the current search path to be copied in the store,
  7300. compiled, and made available in the load path during the execution of
  7301. @var{exp}---e.g., @code{((guix build utils) (guix build
  7302. gnu-build-system))}.
  7303. @var{exp} is evaluated in an environment where @code{%outputs} is bound
  7304. to a list of output/path pairs, and where @code{%build-inputs} is bound
  7305. to a list of string/output-path pairs made from @var{inputs}.
  7306. Optionally, @var{env-vars} is a list of string pairs specifying the name
  7307. and value of environment variables visible to the builder. The builder
  7308. terminates by passing the result of @var{exp} to @code{exit}; thus, when
  7309. @var{exp} returns @code{#f}, the build is considered to have failed.
  7310. @var{exp} is built using @var{guile-for-build} (a derivation). When
  7311. @var{guile-for-build} is omitted or is @code{#f}, the value of the
  7312. @code{%guile-for-build} fluid is used instead.
  7313. See the @code{derivation} procedure for the meaning of
  7314. @var{references-graphs}, @var{allowed-references},
  7315. @var{disallowed-references}, @var{local-build?}, and
  7316. @var{substitutable?}.
  7317. @end deffn
  7318. @noindent
  7319. Here's an example of a single-output derivation that creates a directory
  7320. containing one file:
  7321. @lisp
  7322. (let ((builder '(let ((out (assoc-ref %outputs "out")))
  7323. (mkdir out) ; create /gnu/store/@dots{}-goo
  7324. (call-with-output-file (string-append out "/test")
  7325. (lambda (p)
  7326. (display '(hello guix) p))))))
  7327. (build-expression->derivation store "goo" builder))
  7328. @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
  7329. @end lisp
  7330. @node The Store Monad
  7331. @section The Store Monad
  7332. @cindex monad
  7333. The procedures that operate on the store described in the previous
  7334. sections all take an open connection to the build daemon as their first
  7335. argument. Although the underlying model is functional, they either have
  7336. side effects or depend on the current state of the store.
  7337. The former is inconvenient: the connection to the build daemon has to be
  7338. carried around in all those functions, making it impossible to compose
  7339. functions that do not take that parameter with functions that do. The
  7340. latter can be problematic: since store operations have side effects
  7341. and/or depend on external state, they have to be properly sequenced.
  7342. @cindex monadic values
  7343. @cindex monadic functions
  7344. This is where the @code{(guix monads)} module comes in. This module
  7345. provides a framework for working with @dfn{monads}, and a particularly
  7346. useful monad for our uses, the @dfn{store monad}. Monads are a
  7347. construct that allows two things: associating ``context'' with values
  7348. (in our case, the context is the store), and building sequences of
  7349. computations (here computations include accesses to the store). Values
  7350. in a monad---values that carry this additional context---are called
  7351. @dfn{monadic values}; procedures that return such values are called
  7352. @dfn{monadic procedures}.
  7353. Consider this ``normal'' procedure:
  7354. @lisp
  7355. (define (sh-symlink store)
  7356. ;; Return a derivation that symlinks the 'bash' executable.
  7357. (let* ((drv (package-derivation store bash))
  7358. (out (derivation->output-path drv))
  7359. (sh (string-append out "/bin/bash")))
  7360. (build-expression->derivation store "sh"
  7361. `(symlink ,sh %output))))
  7362. @end lisp
  7363. Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
  7364. as a monadic function:
  7365. @lisp
  7366. (define (sh-symlink)
  7367. ;; Same, but return a monadic value.
  7368. (mlet %store-monad ((drv (package->derivation bash)))
  7369. (gexp->derivation "sh"
  7370. #~(symlink (string-append #$drv "/bin/bash")
  7371. #$output))))
  7372. @end lisp
  7373. There are several things to note in the second version: the @code{store}
  7374. parameter is now implicit and is ``threaded'' in the calls to the
  7375. @code{package->derivation} and @code{gexp->derivation} monadic
  7376. procedures, and the monadic value returned by @code{package->derivation}
  7377. is @dfn{bound} using @code{mlet} instead of plain @code{let}.
  7378. As it turns out, the call to @code{package->derivation} can even be
  7379. omitted since it will take place implicitly, as we will see later
  7380. (@pxref{G-Expressions}):
  7381. @lisp
  7382. (define (sh-symlink)
  7383. (gexp->derivation "sh"
  7384. #~(symlink (string-append #$bash "/bin/bash")
  7385. #$output)))
  7386. @end lisp
  7387. @c See
  7388. @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
  7389. @c for the funny quote.
  7390. Calling the monadic @code{sh-symlink} has no effect. As someone once
  7391. said, ``you exit a monad like you exit a building on fire: by running''.
  7392. So, to exit the monad and get the desired effect, one must use
  7393. @code{run-with-store}:
  7394. @lisp
  7395. (run-with-store (open-connection) (sh-symlink))
  7396. @result{} /gnu/store/...-sh-symlink
  7397. @end lisp
  7398. Note that the @code{(guix monad-repl)} module extends the Guile REPL with
  7399. new ``meta-commands'' to make it easier to deal with monadic procedures:
  7400. @code{run-in-store}, and @code{enter-store-monad}. The former is used
  7401. to ``run'' a single monadic value through the store:
  7402. @example
  7403. scheme@@(guile-user)> ,run-in-store (package->derivation hello)
  7404. $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
  7405. @end example
  7406. The latter enters a recursive REPL, where all the return values are
  7407. automatically run through the store:
  7408. @example
  7409. scheme@@(guile-user)> ,enter-store-monad
  7410. store-monad@@(guile-user) [1]> (package->derivation hello)
  7411. $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
  7412. store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
  7413. $3 = "/gnu/store/@dots{}-foo"
  7414. store-monad@@(guile-user) [1]> ,q
  7415. scheme@@(guile-user)>
  7416. @end example
  7417. @noindent
  7418. Note that non-monadic values cannot be returned in the
  7419. @code{store-monad} REPL.
  7420. The main syntactic forms to deal with monads in general are provided by
  7421. the @code{(guix monads)} module and are described below.
  7422. @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
  7423. Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
  7424. in @var{monad}.
  7425. @end deffn
  7426. @deffn {Scheme Syntax} return @var{val}
  7427. Return a monadic value that encapsulates @var{val}.
  7428. @end deffn
  7429. @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
  7430. @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
  7431. procedures @var{mproc}@dots{}@footnote{This operation is commonly
  7432. referred to as ``bind'', but that name denotes an unrelated procedure in
  7433. Guile. Thus we use this somewhat cryptic symbol inherited from the
  7434. Haskell language.}. There can be one @var{mproc} or several of them, as
  7435. in this example:
  7436. @lisp
  7437. (run-with-state
  7438. (with-monad %state-monad
  7439. (>>= (return 1)
  7440. (lambda (x) (return (+ 1 x)))
  7441. (lambda (x) (return (* 2 x)))))
  7442. 'some-state)
  7443. @result{} 4
  7444. @result{} some-state
  7445. @end lisp
  7446. @end deffn
  7447. @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
  7448. @var{body} ...
  7449. @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
  7450. @var{body} ...
  7451. Bind the variables @var{var} to the monadic values @var{mval} in
  7452. @var{body}, which is a sequence of expressions. As with the bind
  7453. operator, this can be thought of as ``unpacking'' the raw, non-monadic
  7454. value ``contained'' in @var{mval} and making @var{var} refer to that
  7455. raw, non-monadic value within the scope of the @var{body}. The form
  7456. (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
  7457. @var{val}, as per @code{let}. The binding operations occur in sequence
  7458. from left to right. The last expression of @var{body} must be a monadic
  7459. expression, and its result will become the result of the @code{mlet} or
  7460. @code{mlet*} when run in the @var{monad}.
  7461. @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
  7462. (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
  7463. @end deffn
  7464. @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
  7465. Bind @var{mexp} and the following monadic expressions in sequence,
  7466. returning the result of the last expression. Every expression in the
  7467. sequence must be a monadic expression.
  7468. This is akin to @code{mlet}, except that the return values of the
  7469. monadic expressions are ignored. In that sense, it is analogous to
  7470. @code{begin}, but applied to monadic expressions.
  7471. @end deffn
  7472. @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
  7473. When @var{condition} is true, evaluate the sequence of monadic
  7474. expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
  7475. @var{condition} is false, return @code{*unspecified*} in the current
  7476. monad. Every expression in the sequence must be a monadic expression.
  7477. @end deffn
  7478. @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
  7479. When @var{condition} is false, evaluate the sequence of monadic
  7480. expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
  7481. @var{condition} is true, return @code{*unspecified*} in the current
  7482. monad. Every expression in the sequence must be a monadic expression.
  7483. @end deffn
  7484. @cindex state monad
  7485. The @code{(guix monads)} module provides the @dfn{state monad}, which
  7486. allows an additional value---the state---to be @emph{threaded} through
  7487. monadic procedure calls.
  7488. @defvr {Scheme Variable} %state-monad
  7489. The state monad. Procedures in the state monad can access and change
  7490. the state that is threaded.
  7491. Consider the example below. The @code{square} procedure returns a value
  7492. in the state monad. It returns the square of its argument, but also
  7493. increments the current state value:
  7494. @lisp
  7495. (define (square x)
  7496. (mlet %state-monad ((count (current-state)))
  7497. (mbegin %state-monad
  7498. (set-current-state (+ 1 count))
  7499. (return (* x x)))))
  7500. (run-with-state (sequence %state-monad (map square (iota 3))) 0)
  7501. @result{} (0 1 4)
  7502. @result{} 3
  7503. @end lisp
  7504. When ``run'' through @code{%state-monad}, we obtain that additional state
  7505. value, which is the number of @code{square} calls.
  7506. @end defvr
  7507. @deffn {Monadic Procedure} current-state
  7508. Return the current state as a monadic value.
  7509. @end deffn
  7510. @deffn {Monadic Procedure} set-current-state @var{value}
  7511. Set the current state to @var{value} and return the previous state as a
  7512. monadic value.
  7513. @end deffn
  7514. @deffn {Monadic Procedure} state-push @var{value}
  7515. Push @var{value} to the current state, which is assumed to be a list,
  7516. and return the previous state as a monadic value.
  7517. @end deffn
  7518. @deffn {Monadic Procedure} state-pop
  7519. Pop a value from the current state and return it as a monadic value.
  7520. The state is assumed to be a list.
  7521. @end deffn
  7522. @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
  7523. Run monadic value @var{mval} starting with @var{state} as the initial
  7524. state. Return two values: the resulting value, and the resulting state.
  7525. @end deffn
  7526. The main interface to the store monad, provided by the @code{(guix
  7527. store)} module, is as follows.
  7528. @defvr {Scheme Variable} %store-monad
  7529. The store monad---an alias for @code{%state-monad}.
  7530. Values in the store monad encapsulate accesses to the store. When its
  7531. effect is needed, a value of the store monad must be ``evaluated'' by
  7532. passing it to the @code{run-with-store} procedure (see below).
  7533. @end defvr
  7534. @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
  7535. Run @var{mval}, a monadic value in the store monad, in @var{store}, an
  7536. open store connection.
  7537. @end deffn
  7538. @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
  7539. Return as a monadic value the absolute file name in the store of the file
  7540. containing @var{text}, a string. @var{references} is a list of store items that the
  7541. resulting text file refers to; it defaults to the empty list.
  7542. @end deffn
  7543. @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
  7544. Return as a monadic value the absolute file name in the store of the file
  7545. containing @var{data}, a bytevector. @var{references} is a list of store
  7546. items that the resulting binary file refers to; it defaults to the empty list.
  7547. @end deffn
  7548. @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
  7549. [#:recursive? #t] [#:select? (const #t)]
  7550. Return the name of @var{file} once interned in the store. Use
  7551. @var{name} as its store name, or the basename of @var{file} if
  7552. @var{name} is omitted.
  7553. When @var{recursive?} is true, the contents of @var{file} are added
  7554. recursively; if @var{file} designates a flat file and @var{recursive?}
  7555. is true, its contents are added, and its permission bits are kept.
  7556. When @var{recursive?} is true, call @code{(@var{select?} @var{file}
  7557. @var{stat})} for each directory entry, where @var{file} is the entry's
  7558. absolute file name and @var{stat} is the result of @code{lstat}; exclude
  7559. entries for which @var{select?} does not return true.
  7560. The example below adds a file to the store, under two different names:
  7561. @lisp
  7562. (run-with-store (open-connection)
  7563. (mlet %store-monad ((a (interned-file "README"))
  7564. (b (interned-file "README" "LEGU-MIN")))
  7565. (return (list a b))))
  7566. @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
  7567. @end lisp
  7568. @end deffn
  7569. The @code{(guix packages)} module exports the following package-related
  7570. monadic procedures:
  7571. @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
  7572. [#:system (%current-system)] [#:target #f] @
  7573. [#:output "out"]
  7574. Return as a monadic
  7575. value in the absolute file name of @var{file} within the @var{output}
  7576. directory of @var{package}. When @var{file} is omitted, return the name
  7577. of the @var{output} directory of @var{package}. When @var{target} is
  7578. true, use it as a cross-compilation target triplet.
  7579. Note that this procedure does @emph{not} build @var{package}. Thus, the
  7580. result might or might not designate an existing file. We recommend not
  7581. using this procedure unless you know what you are doing.
  7582. @end deffn
  7583. @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
  7584. @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
  7585. @var{target} [@var{system}]
  7586. Monadic version of @code{package-derivation} and
  7587. @code{package-cross-derivation} (@pxref{Defining Packages}).
  7588. @end deffn
  7589. @node G-Expressions
  7590. @section G-Expressions
  7591. @cindex G-expression
  7592. @cindex build code quoting
  7593. So we have ``derivations'', which represent a sequence of build actions
  7594. to be performed to produce an item in the store (@pxref{Derivations}).
  7595. These build actions are performed when asking the daemon to actually
  7596. build the derivations; they are run by the daemon in a container
  7597. (@pxref{Invoking guix-daemon}).
  7598. @cindex code staging
  7599. @cindex staging, of code
  7600. @cindex strata of code
  7601. It should come as no surprise that we like to write these build actions
  7602. in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
  7603. code@footnote{The term @dfn{stratum} in this context was coined by
  7604. Manuel Serrano et al.@: in the context of their work on Hop. Oleg
  7605. Kiselyov, who has written insightful
  7606. @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
  7607. on this topic}, refers to this kind of code generation as
  7608. @dfn{staging}.}: the ``host code''---code that defines packages, talks
  7609. to the daemon, etc.---and the ``build code''---code that actually
  7610. performs build actions, such as making directories, invoking
  7611. @command{make}, and so on (@pxref{Build Phases}).
  7612. To describe a derivation and its build actions, one typically needs to
  7613. embed build code inside host code. It boils down to manipulating build
  7614. code as data, and the homoiconicity of Scheme---code has a direct
  7615. representation as data---comes in handy for that. But we need more than
  7616. the normal @code{quasiquote} mechanism in Scheme to construct build
  7617. expressions.
  7618. The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
  7619. S-expressions adapted to build expressions. G-expressions, or
  7620. @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
  7621. @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
  7622. @code{#$}, and @code{#$@@}), which are comparable to
  7623. @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
  7624. respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
  7625. GNU Guile Reference Manual}). However, there are major differences:
  7626. @itemize
  7627. @item
  7628. Gexps are meant to be written to a file and run or manipulated by other
  7629. processes.
  7630. @item
  7631. When a high-level object such as a package or derivation is unquoted
  7632. inside a gexp, the result is as if its output file name had been
  7633. introduced.
  7634. @item
  7635. Gexps carry information about the packages or derivations they refer to,
  7636. and these dependencies are automatically added as inputs to the build
  7637. processes that use them.
  7638. @end itemize
  7639. @cindex lowering, of high-level objects in gexps
  7640. This mechanism is not limited to package and derivation
  7641. objects: @dfn{compilers} able to ``lower'' other high-level objects to
  7642. derivations or files in the store can be defined,
  7643. such that these objects can also be inserted
  7644. into gexps. For example, a useful type of high-level objects that can be
  7645. inserted in a gexp is ``file-like objects'', which make it easy to
  7646. add files to the store and to refer to them in
  7647. derivations and such (see @code{local-file} and @code{plain-file}
  7648. below).
  7649. To illustrate the idea, here is an example of a gexp:
  7650. @lisp
  7651. (define build-exp
  7652. #~(begin
  7653. (mkdir #$output)
  7654. (chdir #$output)
  7655. (symlink (string-append #$coreutils "/bin/ls")
  7656. "list-files")))
  7657. @end lisp
  7658. This gexp can be passed to @code{gexp->derivation}; we obtain a
  7659. derivation that builds a directory containing exactly one symlink to
  7660. @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
  7661. @lisp
  7662. (gexp->derivation "the-thing" build-exp)
  7663. @end lisp
  7664. As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
  7665. substituted to the reference to the @var{coreutils} package in the
  7666. actual build code, and @var{coreutils} is automatically made an input to
  7667. the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
  7668. output)}) is replaced by a string containing the directory name of the
  7669. output of the derivation.
  7670. @cindex cross compilation
  7671. In a cross-compilation context, it is useful to distinguish between
  7672. references to the @emph{native} build of a package---that can run on the
  7673. host---versus references to cross builds of a package. To that end, the
  7674. @code{#+} plays the same role as @code{#$}, but is a reference to a
  7675. native package build:
  7676. @lisp
  7677. (gexp->derivation "vi"
  7678. #~(begin
  7679. (mkdir #$output)
  7680. (mkdir (string-append #$output "/bin"))
  7681. (system* (string-append #+coreutils "/bin/ln")
  7682. "-s"
  7683. (string-append #$emacs "/bin/emacs")
  7684. (string-append #$output "/bin/vi")))
  7685. #:target "aarch64-linux-gnu")
  7686. @end lisp
  7687. @noindent
  7688. In the example above, the native build of @var{coreutils} is used, so
  7689. that @command{ln} can actually run on the host; but then the
  7690. cross-compiled build of @var{emacs} is referenced.
  7691. @cindex imported modules, for gexps
  7692. @findex with-imported-modules
  7693. Another gexp feature is @dfn{imported modules}: sometimes you want to be
  7694. able to use certain Guile modules from the ``host environment'' in the
  7695. gexp, so those modules should be imported in the ``build environment''.
  7696. The @code{with-imported-modules} form allows you to express that:
  7697. @lisp
  7698. (let ((build (with-imported-modules '((guix build utils))
  7699. #~(begin
  7700. (use-modules (guix build utils))
  7701. (mkdir-p (string-append #$output "/bin"))))))
  7702. (gexp->derivation "empty-dir"
  7703. #~(begin
  7704. #$build
  7705. (display "success!\n")
  7706. #t)))
  7707. @end lisp
  7708. @noindent
  7709. In this example, the @code{(guix build utils)} module is automatically
  7710. pulled into the isolated build environment of our gexp, such that
  7711. @code{(use-modules (guix build utils))} works as expected.
  7712. @cindex module closure
  7713. @findex source-module-closure
  7714. Usually you want the @emph{closure} of the module to be imported---i.e.,
  7715. the module itself and all the modules it depends on---rather than just
  7716. the module; failing to do that, attempts to use the module will fail
  7717. because of missing dependent modules. The @code{source-module-closure}
  7718. procedure computes the closure of a module by looking at its source file
  7719. headers, which comes in handy in this case:
  7720. @lisp
  7721. (use-modules (guix modules)) ;for 'source-module-closure'
  7722. (with-imported-modules (source-module-closure
  7723. '((guix build utils)
  7724. (gnu build vm)))
  7725. (gexp->derivation "something-with-vms"
  7726. #~(begin
  7727. (use-modules (guix build utils)
  7728. (gnu build vm))
  7729. @dots{})))
  7730. @end lisp
  7731. @cindex extensions, for gexps
  7732. @findex with-extensions
  7733. In the same vein, sometimes you want to import not just pure-Scheme
  7734. modules, but also ``extensions'' such as Guile bindings to C libraries
  7735. or other ``full-blown'' packages. Say you need the @code{guile-json}
  7736. package available on the build side, here's how you would do it:
  7737. @lisp
  7738. (use-modules (gnu packages guile)) ;for 'guile-json'
  7739. (with-extensions (list guile-json)
  7740. (gexp->derivation "something-with-json"
  7741. #~(begin
  7742. (use-modules (json))
  7743. @dots{})))
  7744. @end lisp
  7745. The syntactic form to construct gexps is summarized below.
  7746. @deffn {Scheme Syntax} #~@var{exp}
  7747. @deffnx {Scheme Syntax} (gexp @var{exp})
  7748. Return a G-expression containing @var{exp}. @var{exp} may contain one
  7749. or more of the following forms:
  7750. @table @code
  7751. @item #$@var{obj}
  7752. @itemx (ungexp @var{obj})
  7753. Introduce a reference to @var{obj}. @var{obj} may have one of the
  7754. supported types, for example a package or a
  7755. derivation, in which case the @code{ungexp} form is replaced by its
  7756. output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
  7757. If @var{obj} is a list, it is traversed and references to supported
  7758. objects are substituted similarly.
  7759. If @var{obj} is another gexp, its contents are inserted and its
  7760. dependencies are added to those of the containing gexp.
  7761. If @var{obj} is another kind of object, it is inserted as is.
  7762. @item #$@var{obj}:@var{output}
  7763. @itemx (ungexp @var{obj} @var{output})
  7764. This is like the form above, but referring explicitly to the
  7765. @var{output} of @var{obj}---this is useful when @var{obj} produces
  7766. multiple outputs (@pxref{Packages with Multiple Outputs}).
  7767. @item #+@var{obj}
  7768. @itemx #+@var{obj}:output
  7769. @itemx (ungexp-native @var{obj})
  7770. @itemx (ungexp-native @var{obj} @var{output})
  7771. Same as @code{ungexp}, but produces a reference to the @emph{native}
  7772. build of @var{obj} when used in a cross compilation context.
  7773. @item #$output[:@var{output}]
  7774. @itemx (ungexp output [@var{output}])
  7775. Insert a reference to derivation output @var{output}, or to the main
  7776. output when @var{output} is omitted.
  7777. This only makes sense for gexps passed to @code{gexp->derivation}.
  7778. @item #$@@@var{lst}
  7779. @itemx (ungexp-splicing @var{lst})
  7780. Like the above, but splices the contents of @var{lst} inside the
  7781. containing list.
  7782. @item #+@@@var{lst}
  7783. @itemx (ungexp-native-splicing @var{lst})
  7784. Like the above, but refers to native builds of the objects listed in
  7785. @var{lst}.
  7786. @end table
  7787. G-expressions created by @code{gexp} or @code{#~} are run-time objects
  7788. of the @code{gexp?} type (see below).
  7789. @end deffn
  7790. @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
  7791. Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
  7792. in their execution environment.
  7793. Each item in @var{modules} can be the name of a module, such as
  7794. @code{(guix build utils)}, or it can be a module name, followed by an
  7795. arrow, followed by a file-like object:
  7796. @lisp
  7797. `((guix build utils)
  7798. (guix gcrypt)
  7799. ((guix config) => ,(scheme-file "config.scm"
  7800. #~(define-module @dots{}))))
  7801. @end lisp
  7802. @noindent
  7803. In the example above, the first two modules are taken from the search
  7804. path, and the last one is created from the given file-like object.
  7805. This form has @emph{lexical} scope: it has an effect on the gexps
  7806. directly defined in @var{body}@dots{}, but not on those defined, say, in
  7807. procedures called from @var{body}@dots{}.
  7808. @end deffn
  7809. @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
  7810. Mark the gexps defined in @var{body}@dots{} as requiring
  7811. @var{extensions} in their build and execution environment.
  7812. @var{extensions} is typically a list of package objects such as those
  7813. defined in the @code{(gnu packages guile)} module.
  7814. Concretely, the packages listed in @var{extensions} are added to the
  7815. load path while compiling imported modules in @var{body}@dots{}; they
  7816. are also added to the load path of the gexp returned by
  7817. @var{body}@dots{}.
  7818. @end deffn
  7819. @deffn {Scheme Procedure} gexp? @var{obj}
  7820. Return @code{#t} if @var{obj} is a G-expression.
  7821. @end deffn
  7822. G-expressions are meant to be written to disk, either as code building
  7823. some derivation, or as plain files in the store. The monadic procedures
  7824. below allow you to do that (@pxref{The Store Monad}, for more
  7825. information about monads).
  7826. @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
  7827. [#:system (%current-system)] [#:target #f] [#:graft? #t] @
  7828. [#:hash #f] [#:hash-algo #f] @
  7829. [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
  7830. [#:module-path @code{%load-path}] @
  7831. [#:effective-version "2.2"] @
  7832. [#:references-graphs #f] [#:allowed-references #f] @
  7833. [#:disallowed-references #f] @
  7834. [#:leaked-env-vars #f] @
  7835. [#:script-name (string-append @var{name} "-builder")] @
  7836. [#:deprecation-warnings #f] @
  7837. [#:local-build? #f] [#:substitutable? #t] @
  7838. [#:properties '()] [#:guile-for-build #f]
  7839. Return a derivation @var{name} that runs @var{exp} (a gexp) with
  7840. @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
  7841. stored in a file called @var{script-name}. When @var{target} is true,
  7842. it is used as the cross-compilation target triplet for packages referred
  7843. to by @var{exp}.
  7844. @var{modules} is deprecated in favor of @code{with-imported-modules}.
  7845. Its meaning is to
  7846. make @var{modules} available in the evaluation context of @var{exp};
  7847. @var{modules} is a list of names of Guile modules searched in
  7848. @var{module-path} to be copied in the store, compiled, and made available in
  7849. the load path during the execution of @var{exp}---e.g., @code{((guix
  7850. build utils) (guix build gnu-build-system))}.
  7851. @var{effective-version} determines the string to use when adding extensions of
  7852. @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
  7853. @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
  7854. applicable.
  7855. When @var{references-graphs} is true, it must be a list of tuples of one of the
  7856. following forms:
  7857. @example
  7858. (@var{file-name} @var{package})
  7859. (@var{file-name} @var{package} @var{output})
  7860. (@var{file-name} @var{derivation})
  7861. (@var{file-name} @var{derivation} @var{output})
  7862. (@var{file-name} @var{store-item})
  7863. @end example
  7864. The right-hand-side of each element of @var{references-graphs} is automatically made
  7865. an input of the build process of @var{exp}. In the build environment, each
  7866. @var{file-name} contains the reference graph of the corresponding item, in a simple
  7867. text format.
  7868. @var{allowed-references} must be either @code{#f} or a list of output names and packages.
  7869. In the latter case, the list denotes store items that the result is allowed to
  7870. refer to. Any reference to another store item will lead to a build error.
  7871. Similarly for @var{disallowed-references}, which can list items that must not be
  7872. referenced by the outputs.
  7873. @var{deprecation-warnings} determines whether to show deprecation warnings while
  7874. compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
  7875. The other arguments are as for @code{derivation} (@pxref{Derivations}).
  7876. @end deffn
  7877. @cindex file-like objects
  7878. The @code{local-file}, @code{plain-file}, @code{computed-file},
  7879. @code{program-file}, and @code{scheme-file} procedures below return
  7880. @dfn{file-like objects}. That is, when unquoted in a G-expression,
  7881. these objects lead to a file in the store. Consider this G-expression:
  7882. @lisp
  7883. #~(system* #$(file-append glibc "/sbin/nscd") "-f"
  7884. #$(local-file "/tmp/my-nscd.conf"))
  7885. @end lisp
  7886. The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
  7887. to the store. Once expanded, for instance @i{via}
  7888. @code{gexp->derivation}, the G-expression refers to that copy under
  7889. @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
  7890. does not have any effect on what the G-expression does.
  7891. @code{plain-file} can be used similarly; it differs in that the file
  7892. content is directly passed as a string.
  7893. @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
  7894. [#:recursive? #f] [#:select? (const #t)]
  7895. Return an object representing local file @var{file} to add to the store;
  7896. this object can be used in a gexp. If @var{file} is a literal string
  7897. denoting a relative file name, it is looked up relative to the source
  7898. file where it appears; if @var{file} is not a literal string, it is
  7899. looked up relative to the current working directory at run time.
  7900. @var{file} will be added to the store under @var{name}--by default the
  7901. base name of @var{file}.
  7902. When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
  7903. designates a flat file and @var{recursive?} is true, its contents are added, and its
  7904. permission bits are kept.
  7905. When @var{recursive?} is true, call @code{(@var{select?} @var{file}
  7906. @var{stat})} for each directory entry, where @var{file} is the entry's
  7907. absolute file name and @var{stat} is the result of @code{lstat}; exclude
  7908. entries for which @var{select?} does not return true.
  7909. This is the declarative counterpart of the @code{interned-file} monadic
  7910. procedure (@pxref{The Store Monad, @code{interned-file}}).
  7911. @end deffn
  7912. @deffn {Scheme Procedure} plain-file @var{name} @var{content}
  7913. Return an object representing a text file called @var{name} with the given
  7914. @var{content} (a string or a bytevector) to be added to the store.
  7915. This is the declarative counterpart of @code{text-file}.
  7916. @end deffn
  7917. @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
  7918. [#:local-build? #t]
  7919. [#:options '()]
  7920. Return an object representing the store item @var{name}, a file or
  7921. directory computed by @var{gexp}. When @var{local-build?} is true (the
  7922. default), the derivation is built locally. @var{options} is a list of
  7923. additional arguments to pass to @code{gexp->derivation}.
  7924. This is the declarative counterpart of @code{gexp->derivation}.
  7925. @end deffn
  7926. @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
  7927. [#:guile (default-guile)] [#:module-path %load-path] @
  7928. [#:system (%current-system)] [#:target #f]
  7929. Return an executable script @var{name} that runs @var{exp} using
  7930. @var{guile}, with @var{exp}'s imported modules in its search path.
  7931. Look up @var{exp}'s modules in @var{module-path}.
  7932. The example below builds a script that simply invokes the @command{ls}
  7933. command:
  7934. @lisp
  7935. (use-modules (guix gexp) (gnu packages base))
  7936. (gexp->script "list-files"
  7937. #~(execl #$(file-append coreutils "/bin/ls")
  7938. "ls"))
  7939. @end lisp
  7940. When ``running'' it through the store (@pxref{The Store Monad,
  7941. @code{run-with-store}}), we obtain a derivation that produces an
  7942. executable file @file{/gnu/store/@dots{}-list-files} along these lines:
  7943. @example
  7944. #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
  7945. !#
  7946. (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
  7947. @end example
  7948. @end deffn
  7949. @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
  7950. [#:guile #f] [#:module-path %load-path]
  7951. Return an object representing the executable store item @var{name} that
  7952. runs @var{gexp}. @var{guile} is the Guile package used to execute that
  7953. script. Imported modules of @var{gexp} are looked up in @var{module-path}.
  7954. This is the declarative counterpart of @code{gexp->script}.
  7955. @end deffn
  7956. @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
  7957. [#:set-load-path? #t] [#:module-path %load-path] @
  7958. [#:splice? #f] @
  7959. [#:guile (default-guile)]
  7960. Return a derivation that builds a file @var{name} containing @var{exp}.
  7961. When @var{splice?} is true, @var{exp} is considered to be a list of
  7962. expressions that will be spliced in the resulting file.
  7963. When @var{set-load-path?} is true, emit code in the resulting file to
  7964. set @code{%load-path} and @code{%load-compiled-path} to honor
  7965. @var{exp}'s imported modules. Look up @var{exp}'s modules in
  7966. @var{module-path}.
  7967. The resulting file holds references to all the dependencies of @var{exp}
  7968. or a subset thereof.
  7969. @end deffn
  7970. @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} @
  7971. [#:splice? #f] [#:set-load-path? #t]
  7972. Return an object representing the Scheme file @var{name} that contains
  7973. @var{exp}.
  7974. This is the declarative counterpart of @code{gexp->file}.
  7975. @end deffn
  7976. @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
  7977. Return as a monadic value a derivation that builds a text file
  7978. containing all of @var{text}. @var{text} may list, in addition to
  7979. strings, objects of any type that can be used in a gexp: packages,
  7980. derivations, local file objects, etc. The resulting store file holds
  7981. references to all these.
  7982. This variant should be preferred over @code{text-file} anytime the file
  7983. to create will reference items from the store. This is typically the
  7984. case when building a configuration file that embeds store file names,
  7985. like this:
  7986. @lisp
  7987. (define (profile.sh)
  7988. ;; Return the name of a shell script in the store that
  7989. ;; initializes the 'PATH' environment variable.
  7990. (text-file* "profile.sh"
  7991. "export PATH=" coreutils "/bin:"
  7992. grep "/bin:" sed "/bin\n"))
  7993. @end lisp
  7994. In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
  7995. will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
  7996. preventing them from being garbage-collected during its lifetime.
  7997. @end deffn
  7998. @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
  7999. Return an object representing store file @var{name} containing
  8000. @var{text}. @var{text} is a sequence of strings and file-like objects,
  8001. as in:
  8002. @lisp
  8003. (mixed-text-file "profile"
  8004. "export PATH=" coreutils "/bin:" grep "/bin")
  8005. @end lisp
  8006. This is the declarative counterpart of @code{text-file*}.
  8007. @end deffn
  8008. @deffn {Scheme Procedure} file-union @var{name} @var{files}
  8009. Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
  8010. Each item in @var{files} must be a two-element list where the first element is the
  8011. file name to use in the new directory, and the second element is a gexp
  8012. denoting the target file. Here's an example:
  8013. @lisp
  8014. (file-union "etc"
  8015. `(("hosts" ,(plain-file "hosts"
  8016. "127.0.0.1 localhost"))
  8017. ("bashrc" ,(plain-file "bashrc"
  8018. "alias ls='ls --color=auto'"))))
  8019. @end lisp
  8020. This yields an @code{etc} directory containing these two files.
  8021. @end deffn
  8022. @deffn {Scheme Procedure} directory-union @var{name} @var{things}
  8023. Return a directory that is the union of @var{things}, where @var{things} is a list of
  8024. file-like objects denoting directories. For example:
  8025. @lisp
  8026. (directory-union "guile+emacs" (list guile emacs))
  8027. @end lisp
  8028. yields a directory that is the union of the @code{guile} and @code{emacs} packages.
  8029. @end deffn
  8030. @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
  8031. Return a file-like object that expands to the concatenation of @var{obj}
  8032. and @var{suffix}, where @var{obj} is a lowerable object and each
  8033. @var{suffix} is a string.
  8034. As an example, consider this gexp:
  8035. @lisp
  8036. (gexp->script "run-uname"
  8037. #~(system* #$(file-append coreutils
  8038. "/bin/uname")))
  8039. @end lisp
  8040. The same effect could be achieved with:
  8041. @lisp
  8042. (gexp->script "run-uname"
  8043. #~(system* (string-append #$coreutils
  8044. "/bin/uname")))
  8045. @end lisp
  8046. There is one difference though: in the @code{file-append} case, the
  8047. resulting script contains the absolute file name as a string, whereas in
  8048. the second case, the resulting script contains a @code{(string-append
  8049. @dots{})} expression to construct the file name @emph{at run time}.
  8050. @end deffn
  8051. @deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{}
  8052. @deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{}
  8053. Bind @var{system} to the currently targeted system---e.g.,
  8054. @code{"x86_64-linux"}---within @var{body}.
  8055. In the second case, additionally bind @var{target} to the current
  8056. cross-compilation target---a GNU triplet such as
  8057. @code{"arm-linux-gnueabihf"}---or @code{#f} if we are not
  8058. cross-compiling.
  8059. @code{let-system} is useful in the occasional case where the object
  8060. spliced into the gexp depends on the target system, as in this example:
  8061. @lisp
  8062. #~(system*
  8063. #+(let-system system
  8064. (cond ((string-prefix? "armhf-" system)
  8065. (file-append qemu "/bin/qemu-system-arm"))
  8066. ((string-prefix? "x86_64-" system)
  8067. (file-append qemu "/bin/qemu-system-x86_64"))
  8068. (else
  8069. (error "dunno!"))))
  8070. "-net" "user" #$image)
  8071. @end lisp
  8072. @end deffn
  8073. @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
  8074. This macro is similar to the @code{parameterize} form for
  8075. dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
  8076. Guile Reference Manual}). The key difference is that it takes effect
  8077. when the file-like object returned by @var{exp} is lowered to a
  8078. derivation or store item.
  8079. A typical use of @code{with-parameters} is to force the system in effect
  8080. for a given object:
  8081. @lisp
  8082. (with-parameters ((%current-system "i686-linux"))
  8083. coreutils)
  8084. @end lisp
  8085. The example above returns an object that corresponds to the i686 build
  8086. of Coreutils, regardless of the current value of @code{%current-system}.
  8087. @end deffn
  8088. Of course, in addition to gexps embedded in ``host'' code, there are
  8089. also modules containing build tools. To make it clear that they are
  8090. meant to be used in the build stratum, these modules are kept in the
  8091. @code{(guix build @dots{})} name space.
  8092. @cindex lowering, of high-level objects in gexps
  8093. Internally, high-level objects are @dfn{lowered}, using their compiler,
  8094. to either derivations or store items. For instance, lowering a package
  8095. yields a derivation, and lowering a @code{plain-file} yields a store
  8096. item. This is achieved using the @code{lower-object} monadic procedure.
  8097. @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
  8098. [#:target #f]
  8099. Return as a value in @code{%store-monad} the derivation or store item
  8100. corresponding to @var{obj} for @var{system}, cross-compiling for
  8101. @var{target} if @var{target} is true. @var{obj} must be an object that
  8102. has an associated gexp compiler, such as a @code{<package>}.
  8103. @end deffn
  8104. @node Invoking guix repl
  8105. @section Invoking @command{guix repl}
  8106. @cindex REPL, read-eval-print loop, script
  8107. The @command{guix repl} command makes it easier to program Guix in Guile
  8108. by launching a Guile @dfn{read-eval-print loop} (REPL) for interactive
  8109. programming (@pxref{Using Guile Interactively,,, guile,
  8110. GNU Guile Reference Manual}), or by running Guile scripts
  8111. (@pxref{Running Guile Scripts,,, guile,
  8112. GNU Guile Reference Manual}).
  8113. Compared to just launching the @command{guile}
  8114. command, @command{guix repl} guarantees that all the Guix modules and all its
  8115. dependencies are available in the search path.
  8116. The general syntax is:
  8117. @example
  8118. guix repl @var{options} [@var{file} @var{args}]
  8119. @end example
  8120. When a @var{file} argument is provided, @var{file} is
  8121. executed as a Guile scripts:
  8122. @example
  8123. guix repl my-script.scm
  8124. @end example
  8125. To pass arguments to the script, use @code{--} to prevent them from
  8126. being interpreted as arguments to @command{guix repl} itself:
  8127. @example
  8128. guix repl -- my-script.scm --input=foo.txt
  8129. @end example
  8130. To make a script executable directly from the shell, using the guix
  8131. executable that is on the user's search path, add the following two
  8132. lines at the top of the script:
  8133. @example
  8134. @code{#!/usr/bin/env -S guix repl --}
  8135. @code{!#}
  8136. @end example
  8137. Without a file name argument, a Guile REPL is started:
  8138. @example
  8139. $ guix repl
  8140. scheme@@(guile-user)> ,use (gnu packages base)
  8141. scheme@@(guile-user)> coreutils
  8142. $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
  8143. @end example
  8144. @cindex inferiors
  8145. In addition, @command{guix repl} implements a simple machine-readable REPL
  8146. protocol for use by @code{(guix inferior)}, a facility to interact with
  8147. @dfn{inferiors}, separate processes running a potentially different revision
  8148. of Guix.
  8149. The available options are as follows:
  8150. @table @code
  8151. @item --type=@var{type}
  8152. @itemx -t @var{type}
  8153. Start a REPL of the given @var{TYPE}, which can be one of the following:
  8154. @table @code
  8155. @item guile
  8156. This is default, and it spawns a standard full-featured Guile REPL.
  8157. @item machine
  8158. Spawn a REPL that uses the machine-readable protocol. This is the protocol
  8159. that the @code{(guix inferior)} module speaks.
  8160. @end table
  8161. @item --listen=@var{endpoint}
  8162. By default, @command{guix repl} reads from standard input and writes to
  8163. standard output. When this option is passed, it will instead listen for
  8164. connections on @var{endpoint}. Here are examples of valid options:
  8165. @table @code
  8166. @item --listen=tcp:37146
  8167. Accept connections on localhost on port 37146.
  8168. @item --listen=unix:/tmp/socket
  8169. Accept connections on the Unix-domain socket @file{/tmp/socket}.
  8170. @end table
  8171. @item --load-path=@var{directory}
  8172. @itemx -L @var{directory}
  8173. Add @var{directory} to the front of the package module search path
  8174. (@pxref{Package Modules}).
  8175. This allows users to define their own packages and make them visible to
  8176. the script or REPL.
  8177. @item -q
  8178. Inhibit loading of the @file{~/.guile} file. By default, that
  8179. configuration file is loaded when spawning a @code{guile} REPL.
  8180. @end table
  8181. @c *********************************************************************
  8182. @node Utilities
  8183. @chapter Utilities
  8184. This section describes Guix command-line utilities. Some of them are
  8185. primarily targeted at developers and users who write new package
  8186. definitions, while others are more generally useful. They complement
  8187. the Scheme programming interface of Guix in a convenient way.
  8188. @menu
  8189. * Invoking guix build:: Building packages from the command line.
  8190. * Invoking guix edit:: Editing package definitions.
  8191. * Invoking guix download:: Downloading a file and printing its hash.
  8192. * Invoking guix hash:: Computing the cryptographic hash of a file.
  8193. * Invoking guix import:: Importing package definitions.
  8194. * Invoking guix refresh:: Updating package definitions.
  8195. * Invoking guix lint:: Finding errors in package definitions.
  8196. * Invoking guix size:: Profiling disk usage.
  8197. * Invoking guix graph:: Visualizing the graph of packages.
  8198. * Invoking guix publish:: Sharing substitutes.
  8199. * Invoking guix challenge:: Challenging substitute servers.
  8200. * Invoking guix copy:: Copying to and from a remote store.
  8201. * Invoking guix container:: Process isolation.
  8202. * Invoking guix weather:: Assessing substitute availability.
  8203. * Invoking guix processes:: Listing client processes.
  8204. @end menu
  8205. @node Invoking guix build
  8206. @section Invoking @command{guix build}
  8207. @cindex package building
  8208. @cindex @command{guix build}
  8209. The @command{guix build} command builds packages or derivations and
  8210. their dependencies, and prints the resulting store paths. Note that it
  8211. does not modify the user's profile---this is the job of the
  8212. @command{guix package} command (@pxref{Invoking guix package}). Thus,
  8213. it is mainly useful for distribution developers.
  8214. The general syntax is:
  8215. @example
  8216. guix build @var{options} @var{package-or-derivation}@dots{}
  8217. @end example
  8218. As an example, the following command builds the latest versions of Emacs
  8219. and of Guile, displays their build logs, and finally displays the
  8220. resulting directories:
  8221. @example
  8222. guix build emacs guile
  8223. @end example
  8224. Similarly, the following command builds all the available packages:
  8225. @example
  8226. guix build --quiet --keep-going \
  8227. `guix package -A | cut -f1,2 --output-delimiter=@@`
  8228. @end example
  8229. @var{package-or-derivation} may be either the name of a package found in
  8230. the software distribution such as @code{coreutils} or
  8231. @code{coreutils@@8.20}, or a derivation such as
  8232. @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
  8233. package with the corresponding name (and optionally version) is searched
  8234. for among the GNU distribution modules (@pxref{Package Modules}).
  8235. Alternatively, the @option{--expression} option may be used to specify a
  8236. Scheme expression that evaluates to a package; this is useful when
  8237. disambiguating among several same-named packages or package variants is
  8238. needed.
  8239. There may be zero or more @var{options}. The available options are
  8240. described in the subsections below.
  8241. @menu
  8242. * Common Build Options:: Build options for most commands.
  8243. * Package Transformation Options:: Creating variants of packages.
  8244. * Additional Build Options:: Options specific to 'guix build'.
  8245. * Debugging Build Failures:: Real life packaging experience.
  8246. @end menu
  8247. @node Common Build Options
  8248. @subsection Common Build Options
  8249. A number of options that control the build process are common to
  8250. @command{guix build} and other commands that can spawn builds, such as
  8251. @command{guix package} or @command{guix archive}. These are the
  8252. following:
  8253. @table @code
  8254. @item --load-path=@var{directory}
  8255. @itemx -L @var{directory}
  8256. Add @var{directory} to the front of the package module search path
  8257. (@pxref{Package Modules}).
  8258. This allows users to define their own packages and make them visible to
  8259. the command-line tools.
  8260. @item --keep-failed
  8261. @itemx -K
  8262. Keep the build tree of failed builds. Thus, if a build fails, its build
  8263. tree is kept under @file{/tmp}, in a directory whose name is shown at
  8264. the end of the build log. This is useful when debugging build issues.
  8265. @xref{Debugging Build Failures}, for tips and tricks on how to debug
  8266. build issues.
  8267. This option implies @option{--no-offload}, and it has no effect when
  8268. connecting to a remote daemon with a @code{guix://} URI (@pxref{The
  8269. Store, the @env{GUIX_DAEMON_SOCKET} variable}).
  8270. @item --keep-going
  8271. @itemx -k
  8272. Keep going when some of the derivations fail to build; return only once
  8273. all the builds have either completed or failed.
  8274. The default behavior is to stop as soon as one of the specified
  8275. derivations has failed.
  8276. @item --dry-run
  8277. @itemx -n
  8278. Do not build the derivations.
  8279. @anchor{fallback-option}
  8280. @item --fallback
  8281. When substituting a pre-built binary fails, fall back to building
  8282. packages locally (@pxref{Substitution Failure}).
  8283. @item --substitute-urls=@var{urls}
  8284. @anchor{client-substitute-urls}
  8285. Consider @var{urls} the whitespace-separated list of substitute source
  8286. URLs, overriding the default list of URLs of @command{guix-daemon}
  8287. (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
  8288. This means that substitutes may be downloaded from @var{urls}, provided
  8289. they are signed by a key authorized by the system administrator
  8290. (@pxref{Substitutes}).
  8291. When @var{urls} is the empty string, substitutes are effectively
  8292. disabled.
  8293. @item --no-substitutes
  8294. Do not use substitutes for build products. That is, always build things
  8295. locally instead of allowing downloads of pre-built binaries
  8296. (@pxref{Substitutes}).
  8297. @item --no-grafts
  8298. Do not ``graft'' packages. In practice, this means that package updates
  8299. available as grafts are not applied. @xref{Security Updates}, for more
  8300. information on grafts.
  8301. @item --rounds=@var{n}
  8302. Build each derivation @var{n} times in a row, and raise an error if
  8303. consecutive build results are not bit-for-bit identical.
  8304. This is a useful way to detect non-deterministic builds processes.
  8305. Non-deterministic build processes are a problem because they make it
  8306. practically impossible for users to @emph{verify} whether third-party
  8307. binaries are genuine. @xref{Invoking guix challenge}, for more.
  8308. When used in conjunction with @option{--keep-failed}, the differing
  8309. output is kept in the store, under @file{/gnu/store/@dots{}-check}.
  8310. This makes it easy to look for differences between the two results.
  8311. @item --no-offload
  8312. Do not use offload builds to other machines (@pxref{Daemon Offload
  8313. Setup}). That is, always build things locally instead of offloading
  8314. builds to remote machines.
  8315. @item --max-silent-time=@var{seconds}
  8316. When the build or substitution process remains silent for more than
  8317. @var{seconds}, terminate it and report a build failure.
  8318. By default, the daemon's setting is honored (@pxref{Invoking
  8319. guix-daemon, @option{--max-silent-time}}).
  8320. @item --timeout=@var{seconds}
  8321. Likewise, when the build or substitution process lasts for more than
  8322. @var{seconds}, terminate it and report a build failure.
  8323. By default, the daemon's setting is honored (@pxref{Invoking
  8324. guix-daemon, @option{--timeout}}).
  8325. @c Note: This option is actually not part of %standard-build-options but
  8326. @c most programs honor it.
  8327. @cindex verbosity, of the command-line tools
  8328. @cindex build logs, verbosity
  8329. @item -v @var{level}
  8330. @itemx --verbosity=@var{level}
  8331. Use the given verbosity @var{level}, an integer. Choosing 0 means that no
  8332. output is produced, 1 is for quiet output, and 2 shows all the build log
  8333. output on standard error.
  8334. @item --cores=@var{n}
  8335. @itemx -c @var{n}
  8336. Allow the use of up to @var{n} CPU cores for the build. The special
  8337. value @code{0} means to use as many CPU cores as available.
  8338. @item --max-jobs=@var{n}
  8339. @itemx -M @var{n}
  8340. Allow at most @var{n} build jobs in parallel. @xref{Invoking
  8341. guix-daemon, @option{--max-jobs}}, for details about this option and the
  8342. equivalent @command{guix-daemon} option.
  8343. @item --debug=@var{level}
  8344. Produce debugging output coming from the build daemon. @var{level} must be an
  8345. integer between 0 and 5; higher means more verbose output. Setting a level of
  8346. 4 or more may be helpful when debugging setup issues with the build daemon.
  8347. @end table
  8348. Behind the scenes, @command{guix build} is essentially an interface to
  8349. the @code{package-derivation} procedure of the @code{(guix packages)}
  8350. module, and to the @code{build-derivations} procedure of the @code{(guix
  8351. derivations)} module.
  8352. In addition to options explicitly passed on the command line,
  8353. @command{guix build} and other @command{guix} commands that support
  8354. building honor the @env{GUIX_BUILD_OPTIONS} environment variable.
  8355. @defvr {Environment Variable} GUIX_BUILD_OPTIONS
  8356. Users can define this variable to a list of command line options that
  8357. will automatically be used by @command{guix build} and other
  8358. @command{guix} commands that can perform builds, as in the example
  8359. below:
  8360. @example
  8361. $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
  8362. @end example
  8363. These options are parsed independently, and the result is appended to
  8364. the parsed command-line options.
  8365. @end defvr
  8366. @node Package Transformation Options
  8367. @subsection Package Transformation Options
  8368. @cindex package variants
  8369. Another set of command-line options supported by @command{guix build}
  8370. and also @command{guix package} are @dfn{package transformation
  8371. options}. These are options that make it possible to define @dfn{package
  8372. variants}---for instance, packages built from different source code.
  8373. This is a convenient way to create customized packages on the fly
  8374. without having to type in the definitions of package variants
  8375. (@pxref{Defining Packages}).
  8376. Package transformation options are preserved across upgrades:
  8377. @command{guix upgrade} attempts to apply transformation options
  8378. initially used when creating the profile to the upgraded packages.
  8379. The available options are listed below. Most commands support them and
  8380. also support a @option{--help-transform} option that lists all the
  8381. available options and a synopsis (these options are not shown in the
  8382. @option{--help} output for brevity).
  8383. @table @code
  8384. @item --with-source=@var{source}
  8385. @itemx --with-source=@var{package}=@var{source}
  8386. @itemx --with-source=@var{package}@@@var{version}=@var{source}
  8387. Use @var{source} as the source of @var{package}, and @var{version} as
  8388. its version number.
  8389. @var{source} must be a file name or a URL, as for @command{guix
  8390. download} (@pxref{Invoking guix download}).
  8391. When @var{package} is omitted,
  8392. it is taken to be the package name specified on the
  8393. command line that matches the base of @var{source}---e.g.,
  8394. if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
  8395. package is @code{guile}.
  8396. Likewise, when @var{version} is omitted, the version string is inferred from
  8397. @var{source}; in the previous example, it is @code{2.0.10}.
  8398. This option allows users to try out versions of packages other than the
  8399. one provided by the distribution. The example below downloads
  8400. @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
  8401. the @code{ed} package:
  8402. @example
  8403. guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
  8404. @end example
  8405. As a developer, @option{--with-source} makes it easy to test release
  8406. candidates:
  8407. @example
  8408. guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
  8409. @end example
  8410. @dots{} or to build from a checkout in a pristine environment:
  8411. @example
  8412. $ git clone git://git.sv.gnu.org/guix.git
  8413. $ guix build guix --with-source=guix@@1.0=./guix
  8414. @end example
  8415. @item --with-input=@var{package}=@var{replacement}
  8416. Replace dependency on @var{package} by a dependency on
  8417. @var{replacement}. @var{package} must be a package name, and
  8418. @var{replacement} must be a package specification such as @code{guile}
  8419. or @code{guile@@1.8}.
  8420. For instance, the following command builds Guix, but replaces its
  8421. dependency on the current stable version of Guile with a dependency on
  8422. the legacy version of Guile, @code{guile@@2.0}:
  8423. @example
  8424. guix build --with-input=guile=guile@@2.0 guix
  8425. @end example
  8426. This is a recursive, deep replacement. So in this example, both
  8427. @code{guix} and its dependency @code{guile-json} (which also depends on
  8428. @code{guile}) get rebuilt against @code{guile@@2.0}.
  8429. This is implemented using the @code{package-input-rewriting} Scheme
  8430. procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
  8431. @item --with-graft=@var{package}=@var{replacement}
  8432. This is similar to @option{--with-input} but with an important difference:
  8433. instead of rebuilding the whole dependency chain, @var{replacement} is
  8434. built and then @dfn{grafted} onto the binaries that were initially
  8435. referring to @var{package}. @xref{Security Updates}, for more
  8436. information on grafts.
  8437. For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
  8438. and all its dependencies, replacing references to the version of GnuTLS
  8439. they currently refer to:
  8440. @example
  8441. guix build --with-graft=gnutls=gnutls@@3.5.4 wget
  8442. @end example
  8443. This has the advantage of being much faster than rebuilding everything.
  8444. But there is a caveat: it works if and only if @var{package} and
  8445. @var{replacement} are strictly compatible---for example, if they provide
  8446. a library, the application binary interface (ABI) of those libraries
  8447. must be compatible. If @var{replacement} is somehow incompatible with
  8448. @var{package}, then the resulting package may be unusable. Use with
  8449. care!
  8450. @cindex debugging info, rebuilding
  8451. @item --with-debug-info=@var{package}
  8452. Build @var{package} in a way that preserves its debugging info and graft
  8453. it onto packages that depend on it. This is useful if @var{package}
  8454. does not already provide debugging info as a @code{debug} output
  8455. (@pxref{Installing Debugging Files}).
  8456. For example, suppose you're experiencing a crash in Inkscape and would
  8457. like to see what's up in GLib, a library deep down in Inkscape's
  8458. dependency graph. GLib lacks a @code{debug} output, so debugging is
  8459. tough. Fortunately, you rebuild GLib with debugging info and tack it on
  8460. Inkscape:
  8461. @example
  8462. guix install inkscape --with-debug-info=glib
  8463. @end example
  8464. Only GLib needs to be recompiled so this takes a reasonable amount of
  8465. time. @xref{Installing Debugging Files}, for more info.
  8466. @quotation Note
  8467. Under the hood, this option works by passing the @samp{#:strip-binaries?
  8468. #f} to the build system of the package of interest (@pxref{Build
  8469. Systems}). Most build systems support that option but some do not. In
  8470. that case, an error is raised.
  8471. Likewise, if a C/C++ package is built without @code{-g} (which is rarely
  8472. the case), debugging info will remain unavailable even when
  8473. @code{#:strip-binaries?} is false.
  8474. @end quotation
  8475. @cindex tool chain, changing the build tool chain of a package
  8476. @item --with-c-toolchain=@var{package}=@var{toolchain}
  8477. This option changes the compilation of @var{package} and everything that
  8478. depends on it so that they get built with @var{toolchain} instead of the
  8479. default GNU tool chain for C/C++.
  8480. Consider this example:
  8481. @example
  8482. guix build octave-cli \
  8483. --with-c-toolchain=fftw=gcc-toolchain@@10 \
  8484. --with-c-toolchain=fftwf=gcc-toolchain@@10
  8485. @end example
  8486. The command above builds a variant of the @code{fftw} and @code{fftwf}
  8487. packages using version 10 of @code{gcc-toolchain} instead of the default
  8488. tool chain, and then builds a variant of the GNU@tie{}Octave
  8489. command-line interface using them. GNU@tie{}Octave itself is also built
  8490. with @code{gcc-toolchain@@10}.
  8491. This other example builds the Hardware Locality (@code{hwloc}) library
  8492. and its dependents up to @code{intel-mpi-benchmarks} with the Clang C
  8493. compiler:
  8494. @example
  8495. guix build --with-c-toolchain=hwloc=clang-toolchain \
  8496. intel-mpi-benchmarks
  8497. @end example
  8498. @quotation Note
  8499. There can be application binary interface (ABI) incompatibilities among
  8500. tool chains. This is particularly true of the C++ standard library and
  8501. run-time support libraries such as that of OpenMP@. By rebuilding all
  8502. dependents with the same tool chain, @option{--with-c-toolchain} minimizes
  8503. the risks of incompatibility but cannot entirely eliminate them. Choose
  8504. @var{package} wisely.
  8505. @end quotation
  8506. @item --with-git-url=@var{package}=@var{url}
  8507. @cindex Git, using the latest commit
  8508. @cindex latest commit, building
  8509. Build @var{package} from the latest commit of the @code{master} branch of the
  8510. Git repository at @var{url}. Git sub-modules of the repository are fetched,
  8511. recursively.
  8512. For example, the following command builds the NumPy Python library against the
  8513. latest commit of the master branch of Python itself:
  8514. @example
  8515. guix build python-numpy \
  8516. --with-git-url=python=https://github.com/python/cpython
  8517. @end example
  8518. This option can also be combined with @option{--with-branch} or
  8519. @option{--with-commit} (see below).
  8520. @cindex continuous integration
  8521. Obviously, since it uses the latest commit of the given branch, the result of
  8522. such a command varies over time. Nevertheless it is a convenient way to
  8523. rebuild entire software stacks against the latest commit of one or more
  8524. packages. This is particularly useful in the context of continuous
  8525. integration (CI).
  8526. Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
  8527. consecutive accesses to the same repository. You may want to clean it up once
  8528. in a while to save disk space.
  8529. @item --with-branch=@var{package}=@var{branch}
  8530. Build @var{package} from the latest commit of @var{branch}. If the
  8531. @code{source} field of @var{package} is an origin with the @code{git-fetch}
  8532. method (@pxref{origin Reference}) or a @code{git-checkout} object, the
  8533. repository URL is taken from that @code{source}. Otherwise you have to use
  8534. @option{--with-git-url} to specify the URL of the Git repository.
  8535. For instance, the following command builds @code{guile-sqlite3} from the
  8536. latest commit of its @code{master} branch, and then builds @code{guix} (which
  8537. depends on it) and @code{cuirass} (which depends on @code{guix}) against this
  8538. specific @code{guile-sqlite3} build:
  8539. @example
  8540. guix build --with-branch=guile-sqlite3=master cuirass
  8541. @end example
  8542. @item --with-commit=@var{package}=@var{commit}
  8543. This is similar to @option{--with-branch}, except that it builds from
  8544. @var{commit} rather than the tip of a branch. @var{commit} must be a valid
  8545. Git commit SHA1 identifier or a tag.
  8546. @item --with-patch=@var{package}=@var{file}
  8547. Add @var{file} to the list of patches applied to @var{package}, where
  8548. @var{package} is a spec such as @code{python@@3.8} or @code{glibc}.
  8549. @var{file} must contain a patch; it is applied with the flags specified
  8550. in the @code{origin} of @var{package} (@pxref{origin Reference}), which
  8551. by default includes @code{-p1} (@pxref{patch Directories,,, diffutils,
  8552. Comparing and Merging Files}).
  8553. As an example, the command below rebuilds Coreutils with the GNU C
  8554. Library (glibc) patched with the given patch:
  8555. @example
  8556. guix build coreutils --with-patch=glibc=./glibc-frob.patch
  8557. @end example
  8558. In this example, glibc itself as well as everything that leads to
  8559. Coreutils in the dependency graph is rebuilt.
  8560. @cindex upstream, latest version
  8561. @item --with-latest=@var{package}
  8562. So you like living on the bleeding edge? This option is for you! It
  8563. replaces occurrences of @var{package} in the dependency graph with its
  8564. latest upstream version, as reported by @command{guix refresh}
  8565. (@pxref{Invoking guix refresh}).
  8566. It does so by determining the latest upstream release of @var{package}
  8567. (if possible), downloading it, and authenticating it @emph{if} it comes
  8568. with an OpenPGP signature.
  8569. As an example, the command below builds Guix against the latest version
  8570. of Guile-JSON:
  8571. @example
  8572. guix build guix --with-latest=guile-json
  8573. @end example
  8574. There are limitations. First, in cases where the tool cannot or does
  8575. not know how to authenticate source code, you are at risk of running
  8576. malicious code; a warning is emitted in this case. Second, this option
  8577. simply changes the source used in the existing package definitions,
  8578. which is not always sufficient: there might be additional dependencies
  8579. that need to be added, patches to apply, and more generally the quality
  8580. assurance work that Guix developers normally do will be missing.
  8581. You've been warned! In all the other cases, it's a snappy way to stay
  8582. on top. We encourage you to submit patches updating the actual package
  8583. definitions once you have successfully tested an upgrade
  8584. (@pxref{Contributing}).
  8585. @cindex test suite, skipping
  8586. @item --without-tests=@var{package}
  8587. Build @var{package} without running its tests. This can be useful in
  8588. situations where you want to skip the lengthy test suite of a
  8589. intermediate package, or if a package's test suite fails in a
  8590. non-deterministic fashion. It should be used with care because running
  8591. the test suite is a good way to ensure a package is working as intended.
  8592. Turning off tests leads to a different store item. Consequently, when
  8593. using this option, anything that depends on @var{package} must be
  8594. rebuilt, as in this example:
  8595. @example
  8596. guix install --without-tests=python python-notebook
  8597. @end example
  8598. The command above installs @code{python-notebook} on top of
  8599. @code{python} built without running its test suite. To do so, it also
  8600. rebuilds everything that depends on @code{python}, including
  8601. @code{python-notebook} itself.
  8602. Internally, @option{--without-tests} relies on changing the
  8603. @code{#:tests?} option of a package's @code{check} phase (@pxref{Build
  8604. Systems}). Note that some packages use a customized @code{check} phase
  8605. that does not respect a @code{#:tests? #f} setting. Therefore,
  8606. @option{--without-tests} has no effect on these packages.
  8607. @end table
  8608. Wondering how to achieve the same effect using Scheme code, for example
  8609. in your manifest, or how to write your own package transformation?
  8610. @xref{Defining Package Variants}, for an overview of the programming
  8611. interfaces available.
  8612. @node Additional Build Options
  8613. @subsection Additional Build Options
  8614. The command-line options presented below are specific to @command{guix
  8615. build}.
  8616. @table @code
  8617. @item --quiet
  8618. @itemx -q
  8619. Build quietly, without displaying the build log; this is equivalent to
  8620. @option{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
  8621. (or similar) and can always be retrieved using the @option{--log-file} option.
  8622. @item --file=@var{file}
  8623. @itemx -f @var{file}
  8624. Build the package, derivation, or other file-like object that the code within
  8625. @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
  8626. As an example, @var{file} might contain a package definition like this
  8627. (@pxref{Defining Packages}):
  8628. @lisp
  8629. @include package-hello.scm
  8630. @end lisp
  8631. The @var{file} may also contain a JSON representation of one or more
  8632. package definitions. Running @code{guix build -f} on @file{hello.json}
  8633. with the following contents would result in building the packages
  8634. @code{myhello} and @code{greeter}:
  8635. @example
  8636. @verbatiminclude package-hello.json
  8637. @end example
  8638. @item --manifest=@var{manifest}
  8639. @itemx -m @var{manifest}
  8640. Build all packages listed in the given @var{manifest}
  8641. (@pxref{profile-manifest, @option{--manifest}}).
  8642. @item --expression=@var{expr}
  8643. @itemx -e @var{expr}
  8644. Build the package or derivation @var{expr} evaluates to.
  8645. For example, @var{expr} may be @code{(@@ (gnu packages guile)
  8646. guile-1.8)}, which unambiguously designates this specific variant of
  8647. version 1.8 of Guile.
  8648. Alternatively, @var{expr} may be a G-expression, in which case it is used
  8649. as a build program passed to @code{gexp->derivation}
  8650. (@pxref{G-Expressions}).
  8651. Lastly, @var{expr} may refer to a zero-argument monadic procedure
  8652. (@pxref{The Store Monad}). The procedure must return a derivation as a
  8653. monadic value, which is then passed through @code{run-with-store}.
  8654. @item --source
  8655. @itemx -S
  8656. Build the source derivations of the packages, rather than the packages
  8657. themselves.
  8658. For instance, @code{guix build -S gcc} returns something like
  8659. @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
  8660. source tarball.
  8661. The returned source tarball is the result of applying any patches and
  8662. code snippets specified in the package @code{origin} (@pxref{Defining
  8663. Packages}).
  8664. @cindex source, verification
  8665. As with other derivations, the result of building a source derivation
  8666. can be verified using the @option{--check} option (@pxref{build-check}).
  8667. This is useful to validate that a (potentially already built or
  8668. substituted, thus cached) package source matches against its declared
  8669. hash.
  8670. Note that @command{guix build -S} compiles the sources only of the
  8671. specified packages. They do not include the sources of statically
  8672. linked dependencies and by themselves are insufficient for reproducing
  8673. the packages.
  8674. @item --sources
  8675. Fetch and return the source of @var{package-or-derivation} and all their
  8676. dependencies, recursively. This is a handy way to obtain a local copy
  8677. of all the source code needed to build @var{packages}, allowing you to
  8678. eventually build them even without network access. It is an extension
  8679. of the @option{--source} option and can accept one of the following
  8680. optional argument values:
  8681. @table @code
  8682. @item package
  8683. This value causes the @option{--sources} option to behave in the same way
  8684. as the @option{--source} option.
  8685. @item all
  8686. Build the source derivations of all packages, including any source that
  8687. might be listed as @code{inputs}. This is the default value.
  8688. @example
  8689. $ guix build --sources tzdata
  8690. The following derivations will be built:
  8691. /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
  8692. /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
  8693. @end example
  8694. @item transitive
  8695. Build the source derivations of all packages, as well of all transitive
  8696. inputs to the packages. This can be used e.g.@: to
  8697. prefetch package source for later offline building.
  8698. @example
  8699. $ guix build --sources=transitive tzdata
  8700. The following derivations will be built:
  8701. /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
  8702. /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
  8703. /gnu/store/@dots{}-grep-2.21.tar.xz.drv
  8704. /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
  8705. /gnu/store/@dots{}-make-4.1.tar.xz.drv
  8706. /gnu/store/@dots{}-bash-4.3.tar.xz.drv
  8707. @dots{}
  8708. @end example
  8709. @end table
  8710. @item --system=@var{system}
  8711. @itemx -s @var{system}
  8712. Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
  8713. the system type of the build host. The @command{guix build} command allows
  8714. you to repeat this option several times, in which case it builds for all the
  8715. specified systems; other commands ignore extraneous @option{-s} options.
  8716. @quotation Note
  8717. The @option{--system} flag is for @emph{native} compilation and must not
  8718. be confused with cross-compilation. See @option{--target} below for
  8719. information on cross-compilation.
  8720. @end quotation
  8721. An example use of this is on Linux-based systems, which can emulate
  8722. different personalities. For instance, passing
  8723. @option{--system=i686-linux} on an @code{x86_64-linux} system or
  8724. @option{--system=armhf-linux} on an @code{aarch64-linux} system allows
  8725. you to build packages in a complete 32-bit environment.
  8726. @quotation Note
  8727. Building for an @code{armhf-linux} system is unconditionally enabled on
  8728. @code{aarch64-linux} machines, although certain aarch64 chipsets do not
  8729. allow for this functionality, notably the ThunderX.
  8730. @end quotation
  8731. Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
  8732. is enabled (@pxref{Virtualization Services,
  8733. @code{qemu-binfmt-service-type}}), you can build for any system for
  8734. which a QEMU @code{binfmt_misc} handler is installed.
  8735. Builds for a system other than that of the machine you are using can
  8736. also be offloaded to a remote machine of the right architecture.
  8737. @xref{Daemon Offload Setup}, for more information on offloading.
  8738. @item --target=@var{triplet}
  8739. @cindex cross-compilation
  8740. Cross-build for @var{triplet}, which must be a valid GNU triplet, such
  8741. as @code{"aarch64-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
  8742. configuration triplets,, autoconf, Autoconf}).
  8743. @anchor{build-check}
  8744. @item --check
  8745. @cindex determinism, checking
  8746. @cindex reproducibility, checking
  8747. Rebuild @var{package-or-derivation}, which are already available in the
  8748. store, and raise an error if the build results are not bit-for-bit
  8749. identical.
  8750. This mechanism allows you to check whether previously installed
  8751. substitutes are genuine (@pxref{Substitutes}), or whether the build result
  8752. of a package is deterministic. @xref{Invoking guix challenge}, for more
  8753. background information and tools.
  8754. When used in conjunction with @option{--keep-failed}, the differing
  8755. output is kept in the store, under @file{/gnu/store/@dots{}-check}.
  8756. This makes it easy to look for differences between the two results.
  8757. @item --repair
  8758. @cindex repairing store items
  8759. @cindex corruption, recovering from
  8760. Attempt to repair the specified store items, if they are corrupt, by
  8761. re-downloading or rebuilding them.
  8762. This operation is not atomic and thus restricted to @code{root}.
  8763. @item --derivations
  8764. @itemx -d
  8765. Return the derivation paths, not the output paths, of the given
  8766. packages.
  8767. @item --root=@var{file}
  8768. @itemx -r @var{file}
  8769. @cindex GC roots, adding
  8770. @cindex garbage collector roots, adding
  8771. Make @var{file} a symlink to the result, and register it as a garbage
  8772. collector root.
  8773. Consequently, the results of this @command{guix build} invocation are
  8774. protected from garbage collection until @var{file} is removed. When
  8775. that option is omitted, build results are eligible for garbage
  8776. collection as soon as the build completes. @xref{Invoking guix gc}, for
  8777. more on GC roots.
  8778. @item --log-file
  8779. @cindex build logs, access
  8780. Return the build log file names or URLs for the given
  8781. @var{package-or-derivation}, or raise an error if build logs are
  8782. missing.
  8783. This works regardless of how packages or derivations are specified. For
  8784. instance, the following invocations are equivalent:
  8785. @example
  8786. guix build --log-file `guix build -d guile`
  8787. guix build --log-file `guix build guile`
  8788. guix build --log-file guile
  8789. guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
  8790. @end example
  8791. If a log is unavailable locally, and unless @option{--no-substitutes} is
  8792. passed, the command looks for a corresponding log on one of the
  8793. substitute servers (as specified with @option{--substitute-urls}).
  8794. So for instance, imagine you want to see the build log of GDB on MIPS,
  8795. but you are actually on an @code{x86_64} machine:
  8796. @example
  8797. $ guix build --log-file gdb -s aarch64-linux
  8798. https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
  8799. @end example
  8800. You can freely access a huge library of build logs!
  8801. @end table
  8802. @node Debugging Build Failures
  8803. @subsection Debugging Build Failures
  8804. @cindex build failures, debugging
  8805. When defining a new package (@pxref{Defining Packages}), you will
  8806. probably find yourself spending some time debugging and tweaking the
  8807. build until it succeeds. To do that, you need to operate the build
  8808. commands yourself in an environment as close as possible to the one the
  8809. build daemon uses.
  8810. To that end, the first thing to do is to use the @option{--keep-failed}
  8811. or @option{-K} option of @command{guix build}, which will keep the
  8812. failed build tree in @file{/tmp} or whatever directory you specified as
  8813. @env{TMPDIR} (@pxref{Common Build Options, @option{--keep-failed}}).
  8814. From there on, you can @command{cd} to the failed build tree and source
  8815. the @file{environment-variables} file, which contains all the
  8816. environment variable definitions that were in place when the build
  8817. failed. So let's say you're debugging a build failure in package
  8818. @code{foo}; a typical session would look like this:
  8819. @example
  8820. $ guix build foo -K
  8821. @dots{} @i{build fails}
  8822. $ cd /tmp/guix-build-foo.drv-0
  8823. $ source ./environment-variables
  8824. $ cd foo-1.2
  8825. @end example
  8826. Now, you can invoke commands as if you were the daemon (almost) and
  8827. troubleshoot your build process.
  8828. Sometimes it happens that, for example, a package's tests pass when you
  8829. run them manually but they fail when the daemon runs them. This can
  8830. happen because the daemon runs builds in containers where, unlike in our
  8831. environment above, network access is missing, @file{/bin/sh} does not
  8832. exist, etc. (@pxref{Build Environment Setup}).
  8833. In such cases, you may need to run inspect the build process from within
  8834. a container similar to the one the build daemon creates:
  8835. @example
  8836. $ guix build -K foo
  8837. @dots{}
  8838. $ cd /tmp/guix-build-foo.drv-0
  8839. $ guix environment --no-grafts -C foo --ad-hoc strace gdb
  8840. [env]# source ./environment-variables
  8841. [env]# cd foo-1.2
  8842. @end example
  8843. Here, @command{guix environment -C} creates a container and spawns a new
  8844. shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
  8845. strace gdb} part adds the @command{strace} and @command{gdb} commands to
  8846. the container, which you may find handy while debugging. The
  8847. @option{--no-grafts} option makes sure we get the exact same
  8848. environment, with ungrafted packages (@pxref{Security Updates}, for more
  8849. info on grafts).
  8850. To get closer to a container like that used by the build daemon, we can
  8851. remove @file{/bin/sh}:
  8852. @example
  8853. [env]# rm /bin/sh
  8854. @end example
  8855. (Don't worry, this is harmless: this is all happening in the throw-away
  8856. container created by @command{guix environment}.)
  8857. The @command{strace} command is probably not in the search path, but we
  8858. can run:
  8859. @example
  8860. [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
  8861. @end example
  8862. In this way, not only you will have reproduced the environment variables
  8863. the daemon uses, you will also be running the build process in a container
  8864. similar to the one the daemon uses.
  8865. @node Invoking guix edit
  8866. @section Invoking @command{guix edit}
  8867. @cindex @command{guix edit}
  8868. @cindex package definition, editing
  8869. So many packages, so many source files! The @command{guix edit} command
  8870. facilitates the life of users and packagers by pointing their editor at
  8871. the source file containing the definition of the specified packages.
  8872. For instance:
  8873. @example
  8874. guix edit gcc@@4.9 vim
  8875. @end example
  8876. @noindent
  8877. launches the program specified in the @env{VISUAL} or in the
  8878. @env{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
  8879. and that of Vim.
  8880. If you are using a Guix Git checkout (@pxref{Building from Git}), or
  8881. have created your own packages on @env{GUIX_PACKAGE_PATH}
  8882. (@pxref{Package Modules}), you will be able to edit the package
  8883. recipes. In other cases, you will be able to examine the read-only recipes
  8884. for packages currently in the store.
  8885. Instead of @env{GUIX_PACKAGE_PATH}, the command-line option
  8886. @option{--load-path=@var{directory}} (or in short @option{-L
  8887. @var{directory}}) allows you to add @var{directory} to the front of the
  8888. package module search path and so make your own packages visible.
  8889. @node Invoking guix download
  8890. @section Invoking @command{guix download}
  8891. @cindex @command{guix download}
  8892. @cindex downloading package sources
  8893. When writing a package definition, developers typically need to download
  8894. a source tarball, compute its SHA256 hash, and write that
  8895. hash in the package definition (@pxref{Defining Packages}). The
  8896. @command{guix download} tool helps with this task: it downloads a file
  8897. from the given URI, adds it to the store, and prints both its file name
  8898. in the store and its SHA256 hash.
  8899. The fact that the downloaded file is added to the store saves bandwidth:
  8900. when the developer eventually tries to build the newly defined package
  8901. with @command{guix build}, the source tarball will not have to be
  8902. downloaded again because it is already in the store. It is also a
  8903. convenient way to temporarily stash files, which may be deleted
  8904. eventually (@pxref{Invoking guix gc}).
  8905. The @command{guix download} command supports the same URIs as used in
  8906. package definitions. In particular, it supports @code{mirror://} URIs.
  8907. @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
  8908. Guile bindings for GnuTLS are available in the user's environment; when
  8909. they are not available, an error is raised. @xref{Guile Preparations,
  8910. how to install the GnuTLS bindings for Guile,, gnutls-guile,
  8911. GnuTLS-Guile}, for more information.
  8912. @command{guix download} verifies HTTPS server certificates by loading
  8913. the certificates of X.509 authorities from the directory pointed to by
  8914. the @env{SSL_CERT_DIR} environment variable (@pxref{X.509
  8915. Certificates}), unless @option{--no-check-certificate} is used.
  8916. The following options are available:
  8917. @table @code
  8918. @item --hash=@var{algorithm}
  8919. @itemx -H @var{algorithm}
  8920. Compute a hash using the specified @var{algorithm}. @xref{Invoking guix
  8921. hash}, for more information.
  8922. @item --format=@var{fmt}
  8923. @itemx -f @var{fmt}
  8924. Write the hash in the format specified by @var{fmt}. For more
  8925. information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
  8926. @item --no-check-certificate
  8927. Do not validate the X.509 certificates of HTTPS servers.
  8928. When using this option, you have @emph{absolutely no guarantee} that you
  8929. are communicating with the authentic server responsible for the given
  8930. URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
  8931. @item --output=@var{file}
  8932. @itemx -o @var{file}
  8933. Save the downloaded file to @var{file} instead of adding it to the
  8934. store.
  8935. @end table
  8936. @node Invoking guix hash
  8937. @section Invoking @command{guix hash}
  8938. @cindex @command{guix hash}
  8939. The @command{guix hash} command computes the hash of a file.
  8940. It is primarily a convenience tool for anyone contributing to the
  8941. distribution: it computes the cryptographic hash of a file, which can be
  8942. used in the definition of a package (@pxref{Defining Packages}).
  8943. The general syntax is:
  8944. @example
  8945. guix hash @var{option} @var{file}
  8946. @end example
  8947. When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
  8948. hash of data read from standard input. @command{guix hash} has the
  8949. following options:
  8950. @table @code
  8951. @item --hash=@var{algorithm}
  8952. @itemx -H @var{algorithm}
  8953. Compute a hash using the specified @var{algorithm}, @code{sha256} by
  8954. default.
  8955. @var{algorithm} must the name of a cryptographic hash algorithm
  8956. supported by Libgcrypt @i{via} Guile-Gcrypt---e.g., @code{sha512} or
  8957. @code{sha3-256} (@pxref{Hash Functions,,, guile-gcrypt, Guile-Gcrypt
  8958. Reference Manual}).
  8959. @item --format=@var{fmt}
  8960. @itemx -f @var{fmt}
  8961. Write the hash in the format specified by @var{fmt}.
  8962. Supported formats: @code{base64}, @code{nix-base32}, @code{base32}, @code{base16}
  8963. (@code{hex} and @code{hexadecimal} can be used as well).
  8964. If the @option{--format} option is not specified, @command{guix hash}
  8965. will output the hash in @code{nix-base32}. This representation is used
  8966. in the definitions of packages.
  8967. @item --recursive
  8968. @itemx -r
  8969. Compute the hash on @var{file} recursively.
  8970. In this case, the hash is computed on an archive containing @var{file},
  8971. including its children if it is a directory. Some of the metadata of
  8972. @var{file} is part of the archive; for instance, when @var{file} is a
  8973. regular file, the hash is different depending on whether @var{file} is
  8974. executable or not. Metadata such as time stamps has no impact on the
  8975. hash (@pxref{Invoking guix archive}).
  8976. @c FIXME: Replace xref above with xref to an ``Archive'' section when
  8977. @c it exists.
  8978. @item --exclude-vcs
  8979. @itemx -x
  8980. When combined with @option{--recursive}, exclude version control system
  8981. directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.).
  8982. @vindex git-fetch
  8983. As an example, here is how you would compute the hash of a Git checkout,
  8984. which is useful when using the @code{git-fetch} method (@pxref{origin
  8985. Reference}):
  8986. @example
  8987. $ git clone http://example.org/foo.git
  8988. $ cd foo
  8989. $ guix hash -rx .
  8990. @end example
  8991. @end table
  8992. @node Invoking guix import
  8993. @section Invoking @command{guix import}
  8994. @cindex importing packages
  8995. @cindex package import
  8996. @cindex package conversion
  8997. @cindex Invoking @command{guix import}
  8998. The @command{guix import} command is useful for people who would like to
  8999. add a package to the distribution with as little work as
  9000. possible---a legitimate demand. The command knows of a few
  9001. repositories from which it can ``import'' package metadata. The result
  9002. is a package definition, or a template thereof, in the format we know
  9003. (@pxref{Defining Packages}).
  9004. The general syntax is:
  9005. @example
  9006. guix import @var{importer} @var{options}@dots{}
  9007. @end example
  9008. @var{importer} specifies the source from which to import package
  9009. metadata, and @var{options} specifies a package identifier and other
  9010. options specific to @var{importer}.
  9011. Some of the importers rely on the ability to run the @command{gpgv} command.
  9012. For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
  9013. gnupg} if needed.
  9014. Currently, the available ``importers'' are:
  9015. @table @code
  9016. @item gnu
  9017. Import metadata for the given GNU package. This provides a template
  9018. for the latest version of that GNU package, including the hash of its
  9019. source tarball, and its canonical synopsis and description.
  9020. Additional information such as the package dependencies and its
  9021. license needs to be figured out manually.
  9022. For example, the following command returns a package definition for
  9023. GNU@tie{}Hello:
  9024. @example
  9025. guix import gnu hello
  9026. @end example
  9027. Specific command-line options are:
  9028. @table @code
  9029. @item --key-download=@var{policy}
  9030. As for @command{guix refresh}, specify the policy to handle missing
  9031. OpenPGP keys when verifying the package signature. @xref{Invoking guix
  9032. refresh, @option{--key-download}}.
  9033. @end table
  9034. @item pypi
  9035. @cindex pypi
  9036. Import metadata from the @uref{https://pypi.python.org/, Python Package
  9037. Index}. Information is taken from the JSON-formatted description
  9038. available at @code{pypi.python.org} and usually includes all the relevant
  9039. information, including package dependencies. For maximum efficiency, it
  9040. is recommended to install the @command{unzip} utility, so that the
  9041. importer can unzip Python wheels and gather data from them.
  9042. The command below imports metadata for the @code{itsdangerous} Python
  9043. package:
  9044. @example
  9045. guix import pypi itsdangerous
  9046. @end example
  9047. @table @code
  9048. @item --recursive
  9049. @itemx -r
  9050. Traverse the dependency graph of the given upstream package recursively
  9051. and generate package expressions for all those packages that are not yet
  9052. in Guix.
  9053. @end table
  9054. @item gem
  9055. @cindex gem
  9056. Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
  9057. is taken from the JSON-formatted description available at
  9058. @code{rubygems.org} and includes most relevant information, including
  9059. runtime dependencies. There are some caveats, however. The metadata
  9060. doesn't distinguish between synopses and descriptions, so the same string
  9061. is used for both fields. Additionally, the details of non-Ruby
  9062. dependencies required to build native extensions is unavailable and left
  9063. as an exercise to the packager.
  9064. The command below imports metadata for the @code{rails} Ruby package:
  9065. @example
  9066. guix import gem rails
  9067. @end example
  9068. @table @code
  9069. @item --recursive
  9070. @itemx -r
  9071. Traverse the dependency graph of the given upstream package recursively
  9072. and generate package expressions for all those packages that are not yet
  9073. in Guix.
  9074. @end table
  9075. @item cpan
  9076. @cindex CPAN
  9077. Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
  9078. Information is taken from the JSON-formatted metadata provided through
  9079. @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
  9080. relevant information, such as module dependencies. License information
  9081. should be checked closely. If Perl is available in the store, then the
  9082. @code{corelist} utility will be used to filter core modules out of the
  9083. list of dependencies.
  9084. The command command below imports metadata for the Acme::Boolean Perl
  9085. module:
  9086. @example
  9087. guix import cpan Acme::Boolean
  9088. @end example
  9089. @item cran
  9090. @cindex CRAN
  9091. @cindex Bioconductor
  9092. Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
  9093. central repository for the @uref{https://r-project.org, GNU@tie{}R
  9094. statistical and graphical environment}.
  9095. Information is extracted from the @file{DESCRIPTION} file of the package.
  9096. The command command below imports metadata for the Cairo R package:
  9097. @example
  9098. guix import cran Cairo
  9099. @end example
  9100. When @option{--recursive} is added, the importer will traverse the
  9101. dependency graph of the given upstream package recursively and generate
  9102. package expressions for all those packages that are not yet in Guix.
  9103. When @option{--style=specification} is added, the importer will generate
  9104. package definitions whose inputs are package specifications instead of
  9105. references to package variables. This is useful when generated package
  9106. definitions are to be appended to existing user modules, as the list of
  9107. used package modules need not be changed. The default is
  9108. @option{--style=variable}.
  9109. When @option{--archive=bioconductor} is added, metadata is imported from
  9110. @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
  9111. packages for the analysis and comprehension of high-throughput
  9112. genomic data in bioinformatics.
  9113. Information is extracted from the @file{DESCRIPTION} file contained in the
  9114. package archive.
  9115. The command below imports metadata for the GenomicRanges R package:
  9116. @example
  9117. guix import cran --archive=bioconductor GenomicRanges
  9118. @end example
  9119. Finally, you can also import R packages that have not yet been published on
  9120. CRAN or Bioconductor as long as they are in a git repository. Use
  9121. @option{--archive=git} followed by the URL of the git repository:
  9122. @example
  9123. guix import cran --archive=git https://github.com/immunogenomics/harmony
  9124. @end example
  9125. @item texlive
  9126. @cindex TeX Live
  9127. @cindex CTAN
  9128. Import metadata from @uref{https://www.ctan.org/, CTAN}, the
  9129. comprehensive TeX archive network for TeX packages that are part of the
  9130. @uref{https://www.tug.org/texlive/, TeX Live distribution}.
  9131. Information about the package is obtained through the XML API provided
  9132. by CTAN, while the source code is downloaded from the SVN repository of
  9133. the Tex Live project. This is done because the CTAN does not keep
  9134. versioned archives.
  9135. The command command below imports metadata for the @code{fontspec}
  9136. TeX package:
  9137. @example
  9138. guix import texlive fontspec
  9139. @end example
  9140. When @option{--archive=@var{directory}} is added, the source code is
  9141. downloaded not from the @file{latex} sub-directory of the
  9142. @file{texmf-dist/source} tree in the TeX Live SVN repository, but from
  9143. the specified sibling @var{directory} under the same root.
  9144. The command below imports metadata for the @code{ifxetex} package from
  9145. CTAN while fetching the sources from the directory
  9146. @file{texmf/source/generic}:
  9147. @example
  9148. guix import texlive --archive=generic ifxetex
  9149. @end example
  9150. @item json
  9151. @cindex JSON, import
  9152. Import package metadata from a local JSON file. Consider the following
  9153. example package definition in JSON format:
  9154. @example
  9155. @{
  9156. "name": "hello",
  9157. "version": "2.10",
  9158. "source": "mirror://gnu/hello/hello-2.10.tar.gz",
  9159. "build-system": "gnu",
  9160. "home-page": "https://www.gnu.org/software/hello/",
  9161. "synopsis": "Hello, GNU world: An example GNU package",
  9162. "description": "GNU Hello prints a greeting.",
  9163. "license": "GPL-3.0+",
  9164. "native-inputs": ["gettext"]
  9165. @}
  9166. @end example
  9167. The field names are the same as for the @code{<package>} record
  9168. (@xref{Defining Packages}). References to other packages are provided
  9169. as JSON lists of quoted package specification strings such as
  9170. @code{guile} or @code{guile@@2.0}.
  9171. The importer also supports a more explicit source definition using the
  9172. common fields for @code{<origin>} records:
  9173. @example
  9174. @{
  9175. @dots{}
  9176. "source": @{
  9177. "method": "url-fetch",
  9178. "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
  9179. "sha256": @{
  9180. "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
  9181. @}
  9182. @}
  9183. @dots{}
  9184. @}
  9185. @end example
  9186. The command below reads metadata from the JSON file @code{hello.json}
  9187. and outputs a package expression:
  9188. @example
  9189. guix import json hello.json
  9190. @end example
  9191. @item nix
  9192. Import metadata from a local copy of the source of the
  9193. @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
  9194. relies on the @command{nix-instantiate} command of
  9195. @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
  9196. typically written in a mixture of Nix-language and Bash code. This
  9197. command only imports the high-level package structure that is written in
  9198. the Nix language. It normally includes all the basic fields of a
  9199. package definition.
  9200. When importing a GNU package, the synopsis and descriptions are replaced
  9201. by their canonical upstream variant.
  9202. Usually, you will first need to do:
  9203. @example
  9204. export NIX_REMOTE=daemon
  9205. @end example
  9206. @noindent
  9207. so that @command{nix-instantiate} does not try to open the Nix database.
  9208. As an example, the command below imports the package definition of
  9209. LibreOffice (more precisely, it imports the definition of the package
  9210. bound to the @code{libreoffice} top-level attribute):
  9211. @example
  9212. guix import nix ~/path/to/nixpkgs libreoffice
  9213. @end example
  9214. @item hackage
  9215. @cindex hackage
  9216. Import metadata from the Haskell community's central package archive
  9217. @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
  9218. Cabal files and includes all the relevant information, including package
  9219. dependencies.
  9220. Specific command-line options are:
  9221. @table @code
  9222. @item --stdin
  9223. @itemx -s
  9224. Read a Cabal file from standard input.
  9225. @item --no-test-dependencies
  9226. @itemx -t
  9227. Do not include dependencies required only by the test suites.
  9228. @item --cabal-environment=@var{alist}
  9229. @itemx -e @var{alist}
  9230. @var{alist} is a Scheme alist defining the environment in which the
  9231. Cabal conditionals are evaluated. The accepted keys are: @code{os},
  9232. @code{arch}, @code{impl} and a string representing the name of a flag.
  9233. The value associated with a flag has to be either the symbol
  9234. @code{true} or @code{false}. The value associated with other keys
  9235. has to conform to the Cabal file format definition. The default value
  9236. associated with the keys @code{os}, @code{arch} and @code{impl} is
  9237. @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
  9238. @item --recursive
  9239. @itemx -r
  9240. Traverse the dependency graph of the given upstream package recursively
  9241. and generate package expressions for all those packages that are not yet
  9242. in Guix.
  9243. @end table
  9244. The command below imports metadata for the latest version of the
  9245. HTTP Haskell package without including test dependencies and
  9246. specifying the value of the flag @samp{network-uri} as @code{false}:
  9247. @example
  9248. guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
  9249. @end example
  9250. A specific package version may optionally be specified by following the
  9251. package name by an at-sign and a version number as in the following example:
  9252. @example
  9253. guix import hackage mtl@@2.1.3.1
  9254. @end example
  9255. @item stackage
  9256. @cindex stackage
  9257. The @code{stackage} importer is a wrapper around the @code{hackage} one.
  9258. It takes a package name, looks up the package version included in a
  9259. long-term support (LTS) @uref{https://www.stackage.org, Stackage}
  9260. release and uses the @code{hackage} importer to retrieve its metadata.
  9261. Note that it is up to you to select an LTS release compatible with the
  9262. GHC compiler used by Guix.
  9263. Specific command-line options are:
  9264. @table @code
  9265. @item --no-test-dependencies
  9266. @itemx -t
  9267. Do not include dependencies required only by the test suites.
  9268. @item --lts-version=@var{version}
  9269. @itemx -l @var{version}
  9270. @var{version} is the desired LTS release version. If omitted the latest
  9271. release is used.
  9272. @item --recursive
  9273. @itemx -r
  9274. Traverse the dependency graph of the given upstream package recursively
  9275. and generate package expressions for all those packages that are not yet
  9276. in Guix.
  9277. @end table
  9278. The command below imports metadata for the HTTP Haskell package
  9279. included in the LTS Stackage release version 7.18:
  9280. @example
  9281. guix import stackage --lts-version=7.18 HTTP
  9282. @end example
  9283. @item elpa
  9284. @cindex elpa
  9285. Import metadata from an Emacs Lisp Package Archive (ELPA) package
  9286. repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
  9287. Specific command-line options are:
  9288. @table @code
  9289. @item --archive=@var{repo}
  9290. @itemx -a @var{repo}
  9291. @var{repo} identifies the archive repository from which to retrieve the
  9292. information. Currently the supported repositories and their identifiers
  9293. are:
  9294. @itemize -
  9295. @item
  9296. @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
  9297. identifier. This is the default.
  9298. Packages from @code{elpa.gnu.org} are signed with one of the keys
  9299. contained in the GnuPG keyring at
  9300. @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
  9301. @code{emacs} package (@pxref{Package Installation, ELPA package
  9302. signatures,, emacs, The GNU Emacs Manual}).
  9303. @item
  9304. @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
  9305. @code{melpa-stable} identifier.
  9306. @item
  9307. @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
  9308. identifier.
  9309. @end itemize
  9310. @item --recursive
  9311. @itemx -r
  9312. Traverse the dependency graph of the given upstream package recursively
  9313. and generate package expressions for all those packages that are not yet
  9314. in Guix.
  9315. @end table
  9316. @item crate
  9317. @cindex crate
  9318. Import metadata from the crates.io Rust package repository
  9319. @uref{https://crates.io, crates.io}, as in this example:
  9320. @example
  9321. guix import crate blake2-rfc
  9322. @end example
  9323. The crate importer also allows you to specify a version string:
  9324. @example
  9325. guix import crate constant-time-eq@@0.1.0
  9326. @end example
  9327. Additional options include:
  9328. @table @code
  9329. @item --recursive
  9330. @itemx -r
  9331. Traverse the dependency graph of the given upstream package recursively
  9332. and generate package expressions for all those packages that are not yet
  9333. in Guix.
  9334. @end table
  9335. @item opam
  9336. @cindex OPAM
  9337. @cindex OCaml
  9338. Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
  9339. repository used by the OCaml community.
  9340. Additional options include:
  9341. @table @code
  9342. @item --recursive
  9343. @itemx -r
  9344. Traverse the dependency graph of the given upstream package recursively
  9345. and generate package expressions for all those packages that are not yet
  9346. in Guix.
  9347. @item --repo
  9348. Select the given repository (a repository name). Possible values include:
  9349. @itemize
  9350. @item @code{opam}, the default opam repository,
  9351. @item @code{coq} or @code{coq-released}, the stable repository for coq packages,
  9352. @item @code{coq-core-dev}, the repository that contains development versions of coq,
  9353. @item @code{coq-extra-dev}, the repository that contains development versions
  9354. of coq packages.
  9355. @end itemize
  9356. @end table
  9357. @item go
  9358. @cindex go
  9359. Import metadata for a Go module using
  9360. @uref{https://proxy.golang.org, proxy.golang.org}.
  9361. This importer is highly experimental. See the source code for more info
  9362. about the current state.
  9363. @example
  9364. guix import go gopkg.in/yaml.v2
  9365. @end example
  9366. Additional options include:
  9367. @table @code
  9368. @item --recursive
  9369. @itemx -r
  9370. Traverse the dependency graph of the given upstream package recursively
  9371. and generate package expressions for all those packages that are not yet
  9372. in Guix.
  9373. @end table
  9374. @end table
  9375. The structure of the @command{guix import} code is modular. It would be
  9376. useful to have more importers for other package formats, and your help
  9377. is welcome here (@pxref{Contributing}).
  9378. @node Invoking guix refresh
  9379. @section Invoking @command{guix refresh}
  9380. @cindex @command {guix refresh}
  9381. The primary audience of the @command{guix refresh} command is developers
  9382. of the GNU software distribution. By default, it reports any packages
  9383. provided by the distribution that are outdated compared to the latest
  9384. upstream version, like this:
  9385. @example
  9386. $ guix refresh
  9387. gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
  9388. gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
  9389. @end example
  9390. Alternatively, one can specify packages to consider, in which case a
  9391. warning is emitted for packages that lack an updater:
  9392. @example
  9393. $ guix refresh coreutils guile guile-ssh
  9394. gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
  9395. gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
  9396. @end example
  9397. @command{guix refresh} browses the upstream repository of each package and determines
  9398. the highest version number of the releases therein. The command
  9399. knows how to update specific types of packages: GNU packages, ELPA
  9400. packages, etc.---see the documentation for @option{--type} below. There
  9401. are many packages, though, for which it lacks a method to determine
  9402. whether a new upstream release is available. However, the mechanism is
  9403. extensible, so feel free to get in touch with us to add a new method!
  9404. @table @code
  9405. @item --recursive
  9406. Consider the packages specified, and all the packages upon which they depend.
  9407. @example
  9408. $ guix refresh --recursive coreutils
  9409. gnu/packages/acl.scm:40:13: acl would be upgraded from 2.2.53 to 2.3.1
  9410. gnu/packages/m4.scm:30:12: 1.4.18 is already the latest version of m4
  9411. gnu/packages/xml.scm:68:2: warning: no updater for expat
  9412. gnu/packages/multiprecision.scm:40:12: 6.1.2 is already the latest version of gmp
  9413. @dots{}
  9414. @end example
  9415. @end table
  9416. Sometimes the upstream name differs from the package name used in Guix,
  9417. and @command{guix refresh} needs a little help. Most updaters honor the
  9418. @code{upstream-name} property in package definitions, which can be used
  9419. to that effect:
  9420. @lisp
  9421. (define-public network-manager
  9422. (package
  9423. (name "network-manager")
  9424. ;; @dots{}
  9425. (properties '((upstream-name . "NetworkManager")))))
  9426. @end lisp
  9427. When passed @option{--update}, it modifies distribution source files to
  9428. update the version numbers and source tarball hashes of those package
  9429. recipes (@pxref{Defining Packages}). This is achieved by downloading
  9430. each package's latest source tarball and its associated OpenPGP
  9431. signature, authenticating the downloaded tarball against its signature
  9432. using @command{gpgv}, and finally computing its hash---note that GnuPG must be
  9433. installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
  9434. When the public
  9435. key used to sign the tarball is missing from the user's keyring, an
  9436. attempt is made to automatically retrieve it from a public key server;
  9437. when this is successful, the key is added to the user's keyring; otherwise,
  9438. @command{guix refresh} reports an error.
  9439. The following options are supported:
  9440. @table @code
  9441. @item --expression=@var{expr}
  9442. @itemx -e @var{expr}
  9443. Consider the package @var{expr} evaluates to.
  9444. This is useful to precisely refer to a package, as in this example:
  9445. @example
  9446. guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
  9447. @end example
  9448. This command lists the dependents of the ``final'' libc (essentially all
  9449. the packages).
  9450. @item --update
  9451. @itemx -u
  9452. Update distribution source files (package recipes) in place. This is
  9453. usually run from a checkout of the Guix source tree (@pxref{Running
  9454. Guix Before It Is Installed}):
  9455. @example
  9456. $ ./pre-inst-env guix refresh -s non-core -u
  9457. @end example
  9458. @xref{Defining Packages}, for more information on package definitions.
  9459. @item --select=[@var{subset}]
  9460. @itemx -s @var{subset}
  9461. Select all the packages in @var{subset}, one of @code{core} or
  9462. @code{non-core}.
  9463. The @code{core} subset refers to all the packages at the core of the
  9464. distribution---i.e., packages that are used to build ``everything
  9465. else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
  9466. changing one of these packages in the distribution entails a rebuild of
  9467. all the others. Thus, such updates are an inconvenience to users in
  9468. terms of build time or bandwidth used to achieve the upgrade.
  9469. The @code{non-core} subset refers to the remaining packages. It is
  9470. typically useful in cases where an update of the core packages would be
  9471. inconvenient.
  9472. @item --manifest=@var{file}
  9473. @itemx -m @var{file}
  9474. Select all the packages from the manifest in @var{file}. This is useful to
  9475. check if any packages of the user manifest can be updated.
  9476. @item --type=@var{updater}
  9477. @itemx -t @var{updater}
  9478. Select only packages handled by @var{updater} (may be a comma-separated
  9479. list of updaters). Currently, @var{updater} may be one of:
  9480. @table @code
  9481. @item gnu
  9482. the updater for GNU packages;
  9483. @item savannah
  9484. the updater for packages hosted at @uref{https://savannah.gnu.org, Savannah};
  9485. @item gnome
  9486. the updater for GNOME packages;
  9487. @item kde
  9488. the updater for KDE packages;
  9489. @item xorg
  9490. the updater for X.org packages;
  9491. @item kernel.org
  9492. the updater for packages hosted on kernel.org;
  9493. @item elpa
  9494. the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
  9495. @item cran
  9496. the updater for @uref{https://cran.r-project.org/, CRAN} packages;
  9497. @item bioconductor
  9498. the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
  9499. @item cpan
  9500. the updater for @uref{https://www.cpan.org/, CPAN} packages;
  9501. @item pypi
  9502. the updater for @uref{https://pypi.python.org, PyPI} packages.
  9503. @item gem
  9504. the updater for @uref{https://rubygems.org, RubyGems} packages.
  9505. @item github
  9506. the updater for @uref{https://github.com, GitHub} packages.
  9507. @item hackage
  9508. the updater for @uref{https://hackage.haskell.org, Hackage} packages.
  9509. @item stackage
  9510. the updater for @uref{https://www.stackage.org, Stackage} packages.
  9511. @item crate
  9512. the updater for @uref{https://crates.io, Crates} packages.
  9513. @item launchpad
  9514. the updater for @uref{https://launchpad.net, Launchpad} packages.
  9515. @item generic-html
  9516. a generic updater that crawls the HTML page where the source tarball of
  9517. the package is hosted, when applicable.
  9518. @end table
  9519. For instance, the following command only checks for updates of Emacs
  9520. packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
  9521. @example
  9522. $ guix refresh --type=elpa,cran
  9523. gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
  9524. gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
  9525. @end example
  9526. @end table
  9527. In addition, @command{guix refresh} can be passed one or more package
  9528. names, as in this example:
  9529. @example
  9530. $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
  9531. @end example
  9532. @noindent
  9533. The command above specifically updates the @code{emacs} and
  9534. @code{idutils} packages. The @option{--select} option would have no
  9535. effect in this case.
  9536. When considering whether to upgrade a package, it is sometimes
  9537. convenient to know which packages would be affected by the upgrade and
  9538. should be checked for compatibility. For this the following option may
  9539. be used when passing @command{guix refresh} one or more package names:
  9540. @table @code
  9541. @item --list-updaters
  9542. @itemx -L
  9543. List available updaters and exit (see @option{--type} above).
  9544. For each updater, display the fraction of packages it covers; at the
  9545. end, display the fraction of packages covered by all these updaters.
  9546. @item --list-dependent
  9547. @itemx -l
  9548. List top-level dependent packages that would need to be rebuilt as a
  9549. result of upgrading one or more packages.
  9550. @xref{Invoking guix graph, the @code{reverse-package} type of
  9551. @command{guix graph}}, for information on how to visualize the list of
  9552. dependents of a package.
  9553. @end table
  9554. Be aware that the @option{--list-dependent} option only
  9555. @emph{approximates} the rebuilds that would be required as a result of
  9556. an upgrade. More rebuilds might be required under some circumstances.
  9557. @example
  9558. $ guix refresh --list-dependent flex
  9559. Building the following 120 packages would ensure 213 dependent packages are rebuilt:
  9560. hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
  9561. @end example
  9562. The command above lists a set of packages that could be built to check
  9563. for compatibility with an upgraded @code{flex} package.
  9564. @table @code
  9565. @item --list-transitive
  9566. List all the packages which one or more packages depend upon.
  9567. @example
  9568. $ guix refresh --list-transitive flex
  9569. flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
  9570. 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{}
  9571. @end example
  9572. @end table
  9573. The command above lists a set of packages which, when changed, would cause
  9574. @code{flex} to be rebuilt.
  9575. The following options can be used to customize GnuPG operation:
  9576. @table @code
  9577. @item --gpg=@var{command}
  9578. Use @var{command} as the GnuPG 2.x command. @var{command} is searched
  9579. for in @code{$PATH}.
  9580. @item --keyring=@var{file}
  9581. Use @var{file} as the keyring for upstream keys. @var{file} must be in the
  9582. @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
  9583. and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
  9584. (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
  9585. information on a tool to manipulate keybox files).
  9586. When this option is omitted, @command{guix refresh} uses
  9587. @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
  9588. signing keys. OpenPGP signatures are checked against keys from this keyring;
  9589. missing keys are downloaded to this keyring as well (see
  9590. @option{--key-download} below).
  9591. You can export keys from your default GPG keyring into a keybox file using
  9592. commands like this one:
  9593. @example
  9594. gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
  9595. @end example
  9596. Likewise, you can fetch keys to a specific keybox file like this:
  9597. @example
  9598. gpg --no-default-keyring --keyring mykeyring.kbx \
  9599. --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
  9600. @end example
  9601. @xref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
  9602. Privacy Guard}, for more information on GPG's @option{--keyring} option.
  9603. @item --key-download=@var{policy}
  9604. Handle missing OpenPGP keys according to @var{policy}, which may be one
  9605. of:
  9606. @table @code
  9607. @item always
  9608. Always download missing OpenPGP keys from the key server, and add them
  9609. to the user's GnuPG keyring.
  9610. @item never
  9611. Never try to download missing OpenPGP keys. Instead just bail out.
  9612. @item interactive
  9613. When a package signed with an unknown OpenPGP key is encountered, ask
  9614. the user whether to download it or not. This is the default behavior.
  9615. @end table
  9616. @item --key-server=@var{host}
  9617. Use @var{host} as the OpenPGP key server when importing a public key.
  9618. @item --load-path=@var{directory}
  9619. Add @var{directory} to the front of the package module search path
  9620. (@pxref{Package Modules}).
  9621. This allows users to define their own packages and make them visible to
  9622. the command-line tools.
  9623. @end table
  9624. The @code{github} updater uses the
  9625. @uref{https://developer.github.com/v3/, GitHub API} to query for new
  9626. releases. When used repeatedly e.g.@: when refreshing all packages,
  9627. GitHub will eventually refuse to answer any further API requests. By
  9628. default 60 API requests per hour are allowed, and a full refresh on all
  9629. GitHub packages in Guix requires more than this. Authentication with
  9630. GitHub through the use of an API token alleviates these limits. To use
  9631. an API token, set the environment variable @env{GUIX_GITHUB_TOKEN} to a
  9632. token procured from @uref{https://github.com/settings/tokens} or
  9633. otherwise.
  9634. @node Invoking guix lint
  9635. @section Invoking @command{guix lint}
  9636. @cindex @command{guix lint}
  9637. @cindex package, checking for errors
  9638. The @command{guix lint} command is meant to help package developers avoid
  9639. common errors and use a consistent style. It runs a number of checks on
  9640. a given set of packages in order to find common mistakes in their
  9641. definitions. Available @dfn{checkers} include (see
  9642. @option{--list-checkers} for a complete list):
  9643. @table @code
  9644. @item synopsis
  9645. @itemx description
  9646. Validate certain typographical and stylistic rules about package
  9647. descriptions and synopses.
  9648. @item inputs-should-be-native
  9649. Identify inputs that should most likely be native inputs.
  9650. @item source
  9651. @itemx home-page
  9652. @itemx mirror-url
  9653. @itemx github-url
  9654. @itemx source-file-name
  9655. Probe @code{home-page} and @code{source} URLs and report those that are
  9656. invalid. Suggest a @code{mirror://} URL when applicable. If the
  9657. @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
  9658. URL@. Check that the source file name is meaningful, e.g.@: is not just a
  9659. version number or ``git-checkout'', without a declared @code{file-name}
  9660. (@pxref{origin Reference}).
  9661. @item source-unstable-tarball
  9662. Parse the @code{source} URL to determine if a tarball from GitHub is
  9663. autogenerated or if it is a release tarball. Unfortunately GitHub's
  9664. autogenerated tarballs are sometimes regenerated.
  9665. @item derivation
  9666. Check that the derivation of the given packages can be successfully
  9667. computed for all the supported systems (@pxref{Derivations}).
  9668. @item profile-collisions
  9669. Check whether installing the given packages in a profile would lead to
  9670. collisions. Collisions occur when several packages with the same name
  9671. but a different version or a different store file name are propagated.
  9672. @xref{package Reference, @code{propagated-inputs}}, for more information
  9673. on propagated inputs.
  9674. @item archival
  9675. @cindex Software Heritage, source code archive
  9676. @cindex archival of source code, Software Heritage
  9677. Checks whether the package's source code is archived at
  9678. @uref{https://www.softwareheritage.org, Software Heritage}.
  9679. When the source code that is not archived comes from a version-control system
  9680. (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
  9681. ``save'' request so that it eventually archives it. This ensures that the
  9682. source will remain available in the long term, and that Guix can fall back to
  9683. Software Heritage should the source code disappear from its original host.
  9684. The status of recent ``save'' requests can be
  9685. @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
  9686. When source code is a tarball obtained with @code{url-fetch}, simply print a
  9687. message when it is not archived. As of this writing, Software Heritage does
  9688. not allow requests to save arbitrary tarballs; we are working on ways to
  9689. ensure that non-VCS source code is also archived.
  9690. Software Heritage
  9691. @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
  9692. request rate per IP address}. When the limit is reached, @command{guix lint}
  9693. prints a message and the @code{archival} checker stops doing anything until
  9694. that limit has been reset.
  9695. @item cve
  9696. @cindex security vulnerabilities
  9697. @cindex CVE, Common Vulnerabilities and Exposures
  9698. Report known vulnerabilities found in the Common Vulnerabilities and
  9699. Exposures (CVE) databases of the current and past year
  9700. @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
  9701. NIST}.
  9702. To view information about a particular vulnerability, visit pages such as:
  9703. @itemize
  9704. @item
  9705. @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
  9706. @item
  9707. @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
  9708. @end itemize
  9709. @noindent
  9710. where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
  9711. @code{CVE-2015-7554}.
  9712. Package developers can specify in package recipes the
  9713. @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
  9714. name and version of the package when they differ from the name or version
  9715. that Guix uses, as in this example:
  9716. @lisp
  9717. (package
  9718. (name "grub")
  9719. ;; @dots{}
  9720. ;; CPE calls this package "grub2".
  9721. (properties '((cpe-name . "grub2")
  9722. (cpe-version . "2.3"))))
  9723. @end lisp
  9724. @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
  9725. Some entries in the CVE database do not specify which version of a
  9726. package they apply to, and would thus ``stick around'' forever. Package
  9727. developers who found CVE alerts and verified they can be ignored can
  9728. declare them as in this example:
  9729. @lisp
  9730. (package
  9731. (name "t1lib")
  9732. ;; @dots{}
  9733. ;; These CVEs no longer apply and can be safely ignored.
  9734. (properties `((lint-hidden-cve . ("CVE-2011-0433"
  9735. "CVE-2011-1553"
  9736. "CVE-2011-1554"
  9737. "CVE-2011-5244")))))
  9738. @end lisp
  9739. @item formatting
  9740. Warn about obvious source code formatting issues: trailing white space,
  9741. use of tabulations, etc.
  9742. @end table
  9743. The general syntax is:
  9744. @example
  9745. guix lint @var{options} @var{package}@dots{}
  9746. @end example
  9747. If no package is given on the command line, then all packages are checked.
  9748. The @var{options} may be zero or more of the following:
  9749. @table @code
  9750. @item --list-checkers
  9751. @itemx -l
  9752. List and describe all the available checkers that will be run on packages
  9753. and exit.
  9754. @item --checkers
  9755. @itemx -c
  9756. Only enable the checkers specified in a comma-separated list using the
  9757. names returned by @option{--list-checkers}.
  9758. @item --exclude
  9759. @itemx -x
  9760. Only disable the checkers specified in a comma-separated list using the
  9761. names returned by @option{--list-checkers}.
  9762. @item --no-network
  9763. @itemx -n
  9764. Only enable the checkers that do not depend on Internet access.
  9765. @item --load-path=@var{directory}
  9766. @itemx -L @var{directory}
  9767. Add @var{directory} to the front of the package module search path
  9768. (@pxref{Package Modules}).
  9769. This allows users to define their own packages and make them visible to
  9770. the command-line tools.
  9771. @end table
  9772. @node Invoking guix size
  9773. @section Invoking @command{guix size}
  9774. @cindex size
  9775. @cindex package size
  9776. @cindex closure
  9777. @cindex @command{guix size}
  9778. The @command{guix size} command helps package developers profile the
  9779. disk usage of packages. It is easy to overlook the impact of an
  9780. additional dependency added to a package, or the impact of using a
  9781. single output for a package that could easily be split (@pxref{Packages
  9782. with Multiple Outputs}). Such are the typical issues that
  9783. @command{guix size} can highlight.
  9784. The command can be passed one or more package specifications
  9785. such as @code{gcc@@4.8}
  9786. or @code{guile:debug}, or a file name in the store. Consider this
  9787. example:
  9788. @example
  9789. $ guix size coreutils
  9790. store item total self
  9791. /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
  9792. /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
  9793. /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
  9794. /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
  9795. /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
  9796. /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
  9797. /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
  9798. /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
  9799. total: 78.9 MiB
  9800. @end example
  9801. @cindex closure
  9802. The store items listed here constitute the @dfn{transitive closure} of
  9803. Coreutils---i.e., Coreutils and all its dependencies, recursively---as
  9804. would be returned by:
  9805. @example
  9806. $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
  9807. @end example
  9808. Here the output shows three columns next to store items. The first column,
  9809. labeled ``total'', shows the size in mebibytes (MiB) of the closure of
  9810. the store item---that is, its own size plus the size of all its
  9811. dependencies. The next column, labeled ``self'', shows the size of the
  9812. item itself. The last column shows the ratio of the size of the item
  9813. itself to the space occupied by all the items listed here.
  9814. In this example, we see that the closure of Coreutils weighs in at
  9815. 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
  9816. libraries. (That libc and GCC's libraries represent a large fraction of
  9817. the closure is not a problem @i{per se} because they are always available
  9818. on the system anyway.)
  9819. Since the command also accepts store file names, assessing the size of
  9820. a build result is straightforward:
  9821. @example
  9822. guix size $(guix system build config.scm)
  9823. @end example
  9824. When the package(s) passed to @command{guix size} are available in the
  9825. store@footnote{More precisely, @command{guix size} looks for the
  9826. @emph{ungrafted} variant of the given package(s), as returned by
  9827. @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
  9828. for information on grafts.}, @command{guix size} queries the daemon to determine its
  9829. dependencies, and measures its size in the store, similar to @command{du
  9830. -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
  9831. Coreutils}).
  9832. When the given packages are @emph{not} in the store, @command{guix size}
  9833. reports information based on the available substitutes
  9834. (@pxref{Substitutes}). This makes it possible it to profile disk usage of
  9835. store items that are not even on disk, only available remotely.
  9836. You can also specify several package names:
  9837. @example
  9838. $ guix size coreutils grep sed bash
  9839. store item total self
  9840. /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
  9841. /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
  9842. /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
  9843. /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
  9844. @dots{}
  9845. total: 102.3 MiB
  9846. @end example
  9847. @noindent
  9848. In this example we see that the combination of the four packages takes
  9849. 102.3@tie{}MiB in total, which is much less than the sum of each closure
  9850. since they have a lot of dependencies in common.
  9851. When looking at the profile returned by @command{guix size}, you may
  9852. find yourself wondering why a given package shows up in the profile at
  9853. all. To understand it, you can use @command{guix graph --path -t
  9854. references} to display the shortest path between the two packages
  9855. (@pxref{Invoking guix graph}).
  9856. The available options are:
  9857. @table @option
  9858. @item --substitute-urls=@var{urls}
  9859. Use substitute information from @var{urls}.
  9860. @xref{client-substitute-urls, the same option for @code{guix build}}.
  9861. @item --sort=@var{key}
  9862. Sort lines according to @var{key}, one of the following options:
  9863. @table @code
  9864. @item self
  9865. the size of each item (the default);
  9866. @item closure
  9867. the total size of the item's closure.
  9868. @end table
  9869. @item --map-file=@var{file}
  9870. Write a graphical map of disk usage in PNG format to @var{file}.
  9871. For the example above, the map looks like this:
  9872. @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
  9873. produced by @command{guix size}}
  9874. This option requires that
  9875. @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
  9876. installed and visible in Guile's module search path. When that is not
  9877. the case, @command{guix size} fails as it tries to load it.
  9878. @item --system=@var{system}
  9879. @itemx -s @var{system}
  9880. Consider packages for @var{system}---e.g., @code{x86_64-linux}.
  9881. @item --load-path=@var{directory}
  9882. @itemx -L @var{directory}
  9883. Add @var{directory} to the front of the package module search path
  9884. (@pxref{Package Modules}).
  9885. This allows users to define their own packages and make them visible to
  9886. the command-line tools.
  9887. @end table
  9888. @node Invoking guix graph
  9889. @section Invoking @command{guix graph}
  9890. @cindex DAG
  9891. @cindex @command{guix graph}
  9892. @cindex package dependencies
  9893. Packages and their dependencies form a @dfn{graph}, specifically a
  9894. directed acyclic graph (DAG). It can quickly become difficult to have a
  9895. mental model of the package DAG, so the @command{guix graph} command
  9896. provides a visual representation of the DAG@. By default,
  9897. @command{guix graph} emits a DAG representation in the input format of
  9898. @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
  9899. directly to the @command{dot} command of Graphviz. It can also emit an
  9900. HTML page with embedded JavaScript code to display a ``chord diagram''
  9901. in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
  9902. emit Cypher queries to construct a graph in a graph database supporting
  9903. the @uref{https://www.opencypher.org/, openCypher} query language. With
  9904. @option{--path}, it simply displays the shortest path between two
  9905. packages. The general syntax is:
  9906. @example
  9907. guix graph @var{options} @var{package}@dots{}
  9908. @end example
  9909. For example, the following command generates a PDF file representing the
  9910. package DAG for the GNU@tie{}Core Utilities, showing its build-time
  9911. dependencies:
  9912. @example
  9913. guix graph coreutils | dot -Tpdf > dag.pdf
  9914. @end example
  9915. The output looks like this:
  9916. @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
  9917. Nice little graph, no?
  9918. You may find it more pleasant to navigate the graph interactively with
  9919. @command{xdot} (from the @code{xdot} package):
  9920. @example
  9921. guix graph coreutils | xdot -
  9922. @end example
  9923. But there is more than one graph! The one above is concise: it is the
  9924. graph of package objects, omitting implicit inputs such as GCC, libc,
  9925. grep, etc. It is often useful to have such a concise graph, but
  9926. sometimes one may want to see more details. @command{guix graph} supports
  9927. several types of graphs, allowing you to choose the level of detail:
  9928. @table @code
  9929. @item package
  9930. This is the default type used in the example above. It shows the DAG of
  9931. package objects, excluding implicit dependencies. It is concise, but
  9932. filters out many details.
  9933. @item reverse-package
  9934. This shows the @emph{reverse} DAG of packages. For example:
  9935. @example
  9936. guix graph --type=reverse-package ocaml
  9937. @end example
  9938. ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
  9939. you are also interested in cases where OCaml is an implicit dependency, see
  9940. @code{reverse-bag} below).
  9941. Note that for core packages this can yield huge graphs. If all you want
  9942. is to know the number of packages that depend on a given package, use
  9943. @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
  9944. @option{--list-dependent}}).
  9945. @item bag-emerged
  9946. This is the package DAG, @emph{including} implicit inputs.
  9947. For instance, the following command:
  9948. @example
  9949. guix graph --type=bag-emerged coreutils
  9950. @end example
  9951. ...@: yields this bigger graph:
  9952. @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
  9953. At the bottom of the graph, we see all the implicit inputs of
  9954. @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
  9955. Now, note that the dependencies of these implicit inputs---that is, the
  9956. @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
  9957. here, for conciseness.
  9958. @item bag
  9959. Similar to @code{bag-emerged}, but this time including all the bootstrap
  9960. dependencies.
  9961. @item bag-with-origins
  9962. Similar to @code{bag}, but also showing origins and their dependencies.
  9963. @item reverse-bag
  9964. This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
  9965. it also takes implicit dependencies into account. For example:
  9966. @example
  9967. guix graph -t reverse-bag dune
  9968. @end example
  9969. @noindent
  9970. ...@: yields the graph of all packages that depend on Dune, directly or
  9971. indirectly. Since Dune is an @emph{implicit} dependency of many packages
  9972. @i{via} @code{dune-build-system}, this shows a large number of packages,
  9973. whereas @code{reverse-package} would show very few if any.
  9974. @item derivation
  9975. This is the most detailed representation: It shows the DAG of
  9976. derivations (@pxref{Derivations}) and plain store items. Compared to
  9977. the above representation, many additional nodes are visible, including
  9978. build scripts, patches, Guile modules, etc.
  9979. For this type of graph, it is also possible to pass a @file{.drv} file
  9980. name instead of a package name, as in:
  9981. @example
  9982. guix graph -t derivation `guix system build -d my-config.scm`
  9983. @end example
  9984. @item module
  9985. This is the graph of @dfn{package modules} (@pxref{Package Modules}).
  9986. For example, the following command shows the graph for the package
  9987. module that defines the @code{guile} package:
  9988. @example
  9989. guix graph -t module guile | xdot -
  9990. @end example
  9991. @end table
  9992. All the types above correspond to @emph{build-time dependencies}. The
  9993. following graph type represents the @emph{run-time dependencies}:
  9994. @table @code
  9995. @item references
  9996. This is the graph of @dfn{references} of a package output, as returned
  9997. by @command{guix gc --references} (@pxref{Invoking guix gc}).
  9998. If the given package output is not available in the store, @command{guix
  9999. graph} attempts to obtain dependency information from substitutes.
  10000. Here you can also pass a store file name instead of a package name. For
  10001. example, the command below produces the reference graph of your profile
  10002. (which can be big!):
  10003. @example
  10004. guix graph -t references `readlink -f ~/.guix-profile`
  10005. @end example
  10006. @item referrers
  10007. This is the graph of the @dfn{referrers} of a store item, as returned by
  10008. @command{guix gc --referrers} (@pxref{Invoking guix gc}).
  10009. This relies exclusively on local information from your store. For
  10010. instance, let us suppose that the current Inkscape is available in 10
  10011. profiles on your machine; @command{guix graph -t referrers inkscape}
  10012. will show a graph rooted at Inkscape and with those 10 profiles linked
  10013. to it.
  10014. It can help determine what is preventing a store item from being garbage
  10015. collected.
  10016. @end table
  10017. @cindex shortest path, between packages
  10018. Often, the graph of the package you are interested in does not fit on
  10019. your screen, and anyway all you want to know is @emph{why} that package
  10020. actually depends on some seemingly unrelated package. The
  10021. @option{--path} option instructs @command{guix graph} to display the
  10022. shortest path between two packages (or derivations, or store items,
  10023. etc.):
  10024. @example
  10025. $ guix graph --path emacs libunistring
  10026. emacs@@26.3
  10027. mailutils@@3.9
  10028. libunistring@@0.9.10
  10029. $ guix graph --path -t derivation emacs libunistring
  10030. /gnu/store/@dots{}-emacs-26.3.drv
  10031. /gnu/store/@dots{}-mailutils-3.9.drv
  10032. /gnu/store/@dots{}-libunistring-0.9.10.drv
  10033. $ guix graph --path -t references emacs libunistring
  10034. /gnu/store/@dots{}-emacs-26.3
  10035. /gnu/store/@dots{}-libidn2-2.2.0
  10036. /gnu/store/@dots{}-libunistring-0.9.10
  10037. @end example
  10038. The available options are the following:
  10039. @table @option
  10040. @item --type=@var{type}
  10041. @itemx -t @var{type}
  10042. Produce a graph output of @var{type}, where @var{type} must be one of
  10043. the values listed above.
  10044. @item --list-types
  10045. List the supported graph types.
  10046. @item --backend=@var{backend}
  10047. @itemx -b @var{backend}
  10048. Produce a graph using the selected @var{backend}.
  10049. @item --list-backends
  10050. List the supported graph backends.
  10051. Currently, the available backends are Graphviz and d3.js.
  10052. @item --path
  10053. Display the shortest path between two nodes of the type specified by
  10054. @option{--type}. The example below shows the shortest path between
  10055. @code{libreoffice} and @code{llvm} according to the references of
  10056. @code{libreoffice}:
  10057. @example
  10058. $ guix graph --path -t references libreoffice llvm
  10059. /gnu/store/@dots{}-libreoffice-6.4.2.2
  10060. /gnu/store/@dots{}-libepoxy-1.5.4
  10061. /gnu/store/@dots{}-mesa-19.3.4
  10062. /gnu/store/@dots{}-llvm-9.0.1
  10063. @end example
  10064. @item --expression=@var{expr}
  10065. @itemx -e @var{expr}
  10066. Consider the package @var{expr} evaluates to.
  10067. This is useful to precisely refer to a package, as in this example:
  10068. @example
  10069. guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
  10070. @end example
  10071. @item --system=@var{system}
  10072. @itemx -s @var{system}
  10073. Display the graph for @var{system}---e.g., @code{i686-linux}.
  10074. The package dependency graph is largely architecture-independent, but there
  10075. are some architecture-dependent bits that this option allows you to visualize.
  10076. @item --load-path=@var{directory}
  10077. @itemx -L @var{directory}
  10078. Add @var{directory} to the front of the package module search path
  10079. (@pxref{Package Modules}).
  10080. This allows users to define their own packages and make them visible to
  10081. the command-line tools.
  10082. @end table
  10083. On top of that, @command{guix graph} supports all the usual package
  10084. transformation options (@pxref{Package Transformation Options}). This
  10085. makes it easy to view the effect of a graph-rewriting transformation
  10086. such as @option{--with-input}. For example, the command below outputs
  10087. the graph of @code{git} once @code{openssl} has been replaced by
  10088. @code{libressl} everywhere in the graph:
  10089. @example
  10090. guix graph git --with-input=openssl=libressl
  10091. @end example
  10092. So many possibilities, so much fun!
  10093. @node Invoking guix publish
  10094. @section Invoking @command{guix publish}
  10095. @cindex @command{guix publish}
  10096. The purpose of @command{guix publish} is to enable users to easily share
  10097. their store with others, who can then use it as a substitute server
  10098. (@pxref{Substitutes}).
  10099. When @command{guix publish} runs, it spawns an HTTP server which allows
  10100. anyone with network access to obtain substitutes from it. This means
  10101. that any machine running Guix can also act as if it were a build farm,
  10102. since the HTTP interface is compatible with Cuirass, the software behind
  10103. the @code{@value{SUBSTITUTE-SERVER}} build farm.
  10104. For security, each substitute is signed, allowing recipients to check
  10105. their authenticity and integrity (@pxref{Substitutes}). Because
  10106. @command{guix publish} uses the signing key of the system, which is only
  10107. readable by the system administrator, it must be started as root; the
  10108. @option{--user} option makes it drop root privileges early on.
  10109. The signing key pair must be generated before @command{guix publish} is
  10110. launched, using @command{guix archive --generate-key} (@pxref{Invoking
  10111. guix archive}).
  10112. When the @option{--advertise} option is passed, the server advertises
  10113. its availability on the local network using multicast DNS (mDNS) and DNS
  10114. service discovery (DNS-SD), currently @i{via} Guile-Avahi (@pxref{Top,,,
  10115. guile-avahi, Using Avahi in Guile Scheme Programs}).
  10116. The general syntax is:
  10117. @example
  10118. guix publish @var{options}@dots{}
  10119. @end example
  10120. Running @command{guix publish} without any additional arguments will
  10121. spawn an HTTP server on port 8080:
  10122. @example
  10123. guix publish
  10124. @end example
  10125. Once a publishing server has been authorized, the daemon may download
  10126. substitutes from it. @xref{Getting Substitutes from Other Servers}.
  10127. By default, @command{guix publish} compresses archives on the fly as it
  10128. serves them. This ``on-the-fly'' mode is convenient in that it requires
  10129. no setup and is immediately available. However, when serving lots of
  10130. clients, we recommend using the @option{--cache} option, which enables
  10131. caching of the archives before they are sent to clients---see below for
  10132. details. The @command{guix weather} command provides a handy way to
  10133. check what a server provides (@pxref{Invoking guix weather}).
  10134. As a bonus, @command{guix publish} also serves as a content-addressed
  10135. mirror for source files referenced in @code{origin} records
  10136. (@pxref{origin Reference}). For instance, assuming @command{guix
  10137. publish} is running on @code{example.org}, the following URL returns the
  10138. raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
  10139. (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
  10140. @example
  10141. http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
  10142. @end example
  10143. Obviously, these URLs only work for files that are in the store; in
  10144. other cases, they return 404 (``Not Found'').
  10145. @cindex build logs, publication
  10146. Build logs are available from @code{/log} URLs like:
  10147. @example
  10148. http://example.org/log/gwspk@dots{}-guile-2.2.3
  10149. @end example
  10150. @noindent
  10151. When @command{guix-daemon} is configured to save compressed build logs,
  10152. as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
  10153. URLs return the compressed log as-is, with an appropriate
  10154. @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
  10155. running @command{guix-daemon} with @option{--log-compression=gzip} since
  10156. Web browsers can automatically decompress it, which is not the case with
  10157. Bzip2 compression.
  10158. The following options are available:
  10159. @table @code
  10160. @item --port=@var{port}
  10161. @itemx -p @var{port}
  10162. Listen for HTTP requests on @var{port}.
  10163. @item --listen=@var{host}
  10164. Listen on the network interface for @var{host}. The default is to
  10165. accept connections from any interface.
  10166. @item --user=@var{user}
  10167. @itemx -u @var{user}
  10168. Change privileges to @var{user} as soon as possible---i.e., once the
  10169. server socket is open and the signing key has been read.
  10170. @item --compression[=@var{method}[:@var{level}]]
  10171. @itemx -C [@var{method}[:@var{level}]]
  10172. Compress data using the given @var{method} and @var{level}. @var{method} is
  10173. one of @code{lzip}, @code{zstd}, and @code{gzip}; when @var{method} is
  10174. omitted, @code{gzip} is used.
  10175. When @var{level} is zero, disable compression. The range 1 to 9 corresponds
  10176. to different compression levels: 1 is the fastest, and 9 is the best
  10177. (CPU-intensive). The default is 3.
  10178. Usually, @code{lzip} compresses noticeably better than @code{gzip} for a
  10179. small increase in CPU usage; see
  10180. @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip
  10181. Web page}. However, @code{lzip} achieves low decompression throughput
  10182. (on the order of 50@tie{}MiB/s on modern hardware), which can be a
  10183. bottleneck for someone who downloads over a fast network connection.
  10184. The compression ratio of @code{zstd} is between that of @code{lzip} and
  10185. that of @code{gzip}; its main advantage is a
  10186. @uref{https://facebook.github.io/zstd/,high decompression speed}.
  10187. Unless @option{--cache} is used, compression occurs on the fly and
  10188. the compressed streams are not
  10189. cached. Thus, to reduce load on the machine that runs @command{guix
  10190. publish}, it may be a good idea to choose a low compression level, to
  10191. run @command{guix publish} behind a caching proxy, or to use
  10192. @option{--cache}. Using @option{--cache} has the advantage that it
  10193. allows @command{guix publish} to add @code{Content-Length} HTTP header
  10194. to its responses.
  10195. This option can be repeated, in which case every substitute gets compressed
  10196. using all the selected methods, and all of them are advertised. This is
  10197. useful when users may not support all the compression methods: they can select
  10198. the one they support.
  10199. @item --cache=@var{directory}
  10200. @itemx -c @var{directory}
  10201. Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
  10202. and only serve archives that are in cache.
  10203. When this option is omitted, archives and meta-data are created
  10204. on-the-fly. This can reduce the available bandwidth, especially when
  10205. compression is enabled, since this may become CPU-bound. Another
  10206. drawback of the default mode is that the length of archives is not known
  10207. in advance, so @command{guix publish} does not add a
  10208. @code{Content-Length} HTTP header to its responses, which in turn
  10209. prevents clients from knowing the amount of data being downloaded.
  10210. Conversely, when @option{--cache} is used, the first request for a store
  10211. item (@i{via} a @code{.narinfo} URL) triggers a
  10212. background process to @dfn{bake} the archive---computing its
  10213. @code{.narinfo} and compressing the archive, if needed. Once the
  10214. archive is cached in @var{directory}, subsequent requests succeed and
  10215. are served directly from the cache, which guarantees that clients get
  10216. the best possible bandwidth.
  10217. That first @code{.narinfo} request nonetheless returns 200, provided the
  10218. requested store item is ``small enough'', below the cache bypass
  10219. threshold---see @option{--cache-bypass-threshold} below. That way,
  10220. clients do not have to wait until the archive is baked. For larger
  10221. store items, the first @code{.narinfo} request returns 404, meaning that
  10222. clients have to wait until the archive is baked.
  10223. The ``baking'' process is performed by worker threads. By default, one
  10224. thread per CPU core is created, but this can be customized. See
  10225. @option{--workers} below.
  10226. When @option{--ttl} is used, cached entries are automatically deleted
  10227. when they have expired.
  10228. @item --workers=@var{N}
  10229. When @option{--cache} is used, request the allocation of @var{N} worker
  10230. threads to ``bake'' archives.
  10231. @item --ttl=@var{ttl}
  10232. Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
  10233. (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
  10234. days, @code{1m} means 1 month, and so on.
  10235. This allows the user's Guix to keep substitute information in cache for
  10236. @var{ttl}. However, note that @code{guix publish} does not itself
  10237. guarantee that the store items it provides will indeed remain available
  10238. for as long as @var{ttl}.
  10239. Additionally, when @option{--cache} is used, cached entries that have
  10240. not been accessed for @var{ttl} and that no longer have a corresponding
  10241. item in the store, may be deleted.
  10242. @item --cache-bypass-threshold=@var{size}
  10243. When used in conjunction with @option{--cache}, store items smaller than
  10244. @var{size} are immediately available, even when they are not yet in
  10245. cache. @var{size} is a size in bytes, or it can be suffixed by @code{M}
  10246. for megabytes and so on. The default is @code{10M}.
  10247. ``Cache bypass'' allows you to reduce the publication delay for clients
  10248. at the expense of possibly additional I/O and CPU use on the server
  10249. side: depending on the client access patterns, those store items can end
  10250. up being baked several times until a copy is available in cache.
  10251. Increasing the threshold may be useful for sites that have few users, or
  10252. to guarantee that users get substitutes even for store items that are
  10253. not popular.
  10254. @item --nar-path=@var{path}
  10255. Use @var{path} as the prefix for the URLs of ``nar'' files
  10256. (@pxref{Invoking guix archive, normalized archives}).
  10257. By default, nars are served at a URL such as
  10258. @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
  10259. change the @code{/nar} part to @var{path}.
  10260. @item --public-key=@var{file}
  10261. @itemx --private-key=@var{file}
  10262. Use the specific @var{file}s as the public/private key pair used to sign
  10263. the store items being published.
  10264. The files must correspond to the same key pair (the private key is used
  10265. for signing and the public key is merely advertised in the signature
  10266. metadata). They must contain keys in the canonical s-expression format
  10267. as produced by @command{guix archive --generate-key} (@pxref{Invoking
  10268. guix archive}). By default, @file{/etc/guix/signing-key.pub} and
  10269. @file{/etc/guix/signing-key.sec} are used.
  10270. @item --repl[=@var{port}]
  10271. @itemx -r [@var{port}]
  10272. Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
  10273. Reference Manual}) on @var{port} (37146 by default). This is used
  10274. primarily for debugging a running @command{guix publish} server.
  10275. @end table
  10276. Enabling @command{guix publish} on Guix System is a one-liner: just
  10277. instantiate a @code{guix-publish-service-type} service in the @code{services} field
  10278. of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
  10279. @code{guix-publish-service-type}}).
  10280. If you are instead running Guix on a ``foreign distro'', follow these
  10281. instructions:
  10282. @itemize
  10283. @item
  10284. If your host distro uses the systemd init system:
  10285. @example
  10286. # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
  10287. /etc/systemd/system/
  10288. # systemctl start guix-publish && systemctl enable guix-publish
  10289. @end example
  10290. @item
  10291. If your host distro uses the Upstart init system:
  10292. @example
  10293. # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
  10294. # start guix-publish
  10295. @end example
  10296. @item
  10297. Otherwise, proceed similarly with your distro's init system.
  10298. @end itemize
  10299. @node Invoking guix challenge
  10300. @section Invoking @command{guix challenge}
  10301. @cindex reproducible builds
  10302. @cindex verifiable builds
  10303. @cindex @command{guix challenge}
  10304. @cindex challenge
  10305. Do the binaries provided by this server really correspond to the source
  10306. code it claims to build? Is a package build process deterministic?
  10307. These are the questions the @command{guix challenge} command attempts to
  10308. answer.
  10309. The former is obviously an important question: Before using a substitute
  10310. server (@pxref{Substitutes}), one had better @emph{verify} that it
  10311. provides the right binaries, and thus @emph{challenge} it. The latter
  10312. is what enables the former: If package builds are deterministic, then
  10313. independent builds of the package should yield the exact same result,
  10314. bit for bit; if a server provides a binary different from the one
  10315. obtained locally, it may be either corrupt or malicious.
  10316. We know that the hash that shows up in @file{/gnu/store} file names is
  10317. the hash of all the inputs of the process that built the file or
  10318. directory---compilers, libraries, build scripts,
  10319. etc. (@pxref{Introduction}). Assuming deterministic build processes,
  10320. one store file name should map to exactly one build output.
  10321. @command{guix challenge} checks whether there is, indeed, a single
  10322. mapping by comparing the build outputs of several independent builds of
  10323. any given store item.
  10324. The command output looks like this:
  10325. @smallexample
  10326. $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
  10327. updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
  10328. updating list of substitutes from 'https://guix.example.org'... 100.0%
  10329. /gnu/store/@dots{}-openssl-1.0.2d contents differ:
  10330. local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
  10331. https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
  10332. https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
  10333. differing files:
  10334. /lib/libcrypto.so.1.1
  10335. /lib/libssl.so.1.1
  10336. /gnu/store/@dots{}-git-2.5.0 contents differ:
  10337. local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
  10338. https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
  10339. https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
  10340. differing file:
  10341. /libexec/git-core/git-fsck
  10342. /gnu/store/@dots{}-pius-2.1.1 contents differ:
  10343. local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
  10344. https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
  10345. https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
  10346. differing file:
  10347. /share/man/man1/pius.1.gz
  10348. @dots{}
  10349. 6,406 store items were analyzed:
  10350. - 4,749 (74.1%) were identical
  10351. - 525 (8.2%) differed
  10352. - 1,132 (17.7%) were inconclusive
  10353. @end smallexample
  10354. @noindent
  10355. In this example, @command{guix challenge} first scans the store to
  10356. determine the set of locally-built derivations---as opposed to store
  10357. items that were downloaded from a substitute server---and then queries
  10358. all the substitute servers. It then reports those store items for which
  10359. the servers obtained a result different from the local build.
  10360. @cindex non-determinism, in package builds
  10361. As an example, @code{guix.example.org} always gets a different answer.
  10362. Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
  10363. case of Git. This might indicate that the build process of Git is
  10364. non-deterministic, meaning that its output varies as a function of
  10365. various things that Guix does not fully control, in spite of building
  10366. packages in isolated environments (@pxref{Features}). Most common
  10367. sources of non-determinism include the addition of timestamps in build
  10368. results, the inclusion of random numbers, and directory listings sorted
  10369. by inode number. See @uref{https://reproducible-builds.org/docs/}, for
  10370. more information.
  10371. To find out what is wrong with this Git binary, the easiest approach is
  10372. to run:
  10373. @example
  10374. guix challenge git \
  10375. --diff=diffoscope \
  10376. --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
  10377. @end example
  10378. This automatically invokes @command{diffoscope}, which displays detailed
  10379. information about files that differ.
  10380. Alternatively, we can do something along these lines (@pxref{Invoking guix
  10381. archive}):
  10382. @example
  10383. $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-git-2.5.0 \
  10384. | lzip -d | guix archive -x /tmp/git
  10385. $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
  10386. @end example
  10387. This command shows the difference between the files resulting from the
  10388. local build, and the files resulting from the build on
  10389. @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
  10390. diffutils, Comparing and Merging Files}). The @command{diff} command
  10391. works great for text files. When binary files differ, a better option
  10392. is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
  10393. visualize differences for all kinds of files.
  10394. Once you have done that work, you can tell whether the differences are due
  10395. to a non-deterministic build process or to a malicious server. We try
  10396. hard to remove sources of non-determinism in packages to make it easier
  10397. to verify substitutes, but of course, this is a process that
  10398. involves not just Guix, but a large part of the free software community.
  10399. In the meantime, @command{guix challenge} is one tool to help address
  10400. the problem.
  10401. If you are writing packages for Guix, you are encouraged to check
  10402. whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
  10403. same build result as you did with:
  10404. @example
  10405. $ guix challenge @var{package}
  10406. @end example
  10407. @noindent
  10408. where @var{package} is a package specification such as
  10409. @code{guile@@2.0} or @code{glibc:debug}.
  10410. The general syntax is:
  10411. @example
  10412. guix challenge @var{options} [@var{packages}@dots{}]
  10413. @end example
  10414. When a difference is found between the hash of a locally-built item and
  10415. that of a server-provided substitute, or among substitutes provided by
  10416. different servers, the command displays it as in the example above and
  10417. its exit code is 2 (other non-zero exit codes denote other kinds of
  10418. errors).
  10419. The one option that matters is:
  10420. @table @code
  10421. @item --substitute-urls=@var{urls}
  10422. Consider @var{urls} the whitespace-separated list of substitute source
  10423. URLs to compare to.
  10424. @item --diff=@var{mode}
  10425. Upon mismatches, show differences according to @var{mode}, one of:
  10426. @table @asis
  10427. @item @code{simple} (the default)
  10428. Show the list of files that differ.
  10429. @item @code{diffoscope}
  10430. @itemx @var{command}
  10431. Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
  10432. two directories whose contents do not match.
  10433. When @var{command} is an absolute file name, run @var{command} instead
  10434. of Diffoscope.
  10435. @item @code{none}
  10436. Do not show further details about the differences.
  10437. @end table
  10438. Thus, unless @option{--diff=none} is passed, @command{guix challenge}
  10439. downloads the store items from the given substitute servers so that it
  10440. can compare them.
  10441. @item --verbose
  10442. @itemx -v
  10443. Show details about matches (identical contents) in addition to
  10444. information about mismatches.
  10445. @end table
  10446. @node Invoking guix copy
  10447. @section Invoking @command{guix copy}
  10448. @cindex copy, of store items, over SSH
  10449. @cindex SSH, copy of store items
  10450. @cindex sharing store items across machines
  10451. @cindex transferring store items across machines
  10452. The @command{guix copy} command copies items from the store of one
  10453. machine to that of another machine over a secure shell (SSH)
  10454. connection@footnote{This command is available only when Guile-SSH was
  10455. found. @xref{Requirements}, for details.}. For example, the following
  10456. command copies the @code{coreutils} package, the user's profile, and all
  10457. their dependencies over to @var{host}, logged in as @var{user}:
  10458. @example
  10459. guix copy --to=@var{user}@@@var{host} \
  10460. coreutils `readlink -f ~/.guix-profile`
  10461. @end example
  10462. If some of the items to be copied are already present on @var{host},
  10463. they are not actually sent.
  10464. The command below retrieves @code{libreoffice} and @code{gimp} from
  10465. @var{host}, assuming they are available there:
  10466. @example
  10467. guix copy --from=@var{host} libreoffice gimp
  10468. @end example
  10469. The SSH connection is established using the Guile-SSH client, which is
  10470. compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
  10471. @file{~/.ssh/config}, and uses the SSH agent for authentication.
  10472. The key used to sign items that are sent must be accepted by the remote
  10473. machine. Likewise, the key used by the remote machine to sign items you
  10474. are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
  10475. own daemon. @xref{Invoking guix archive}, for more information about
  10476. store item authentication.
  10477. The general syntax is:
  10478. @example
  10479. guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
  10480. @end example
  10481. You must always specify one of the following options:
  10482. @table @code
  10483. @item --to=@var{spec}
  10484. @itemx --from=@var{spec}
  10485. Specify the host to send to or receive from. @var{spec} must be an SSH
  10486. spec such as @code{example.org}, @code{charlie@@example.org}, or
  10487. @code{charlie@@example.org:2222}.
  10488. @end table
  10489. The @var{items} can be either package names, such as @code{gimp}, or
  10490. store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
  10491. When specifying the name of a package to send, it is first built if
  10492. needed, unless @option{--dry-run} was specified. Common build options
  10493. are supported (@pxref{Common Build Options}).
  10494. @node Invoking guix container
  10495. @section Invoking @command{guix container}
  10496. @cindex container
  10497. @cindex @command{guix container}
  10498. @quotation Note
  10499. As of version @value{VERSION}, this tool is experimental. The interface
  10500. is subject to radical change in the future.
  10501. @end quotation
  10502. The purpose of @command{guix container} is to manipulate processes
  10503. running within an isolated environment, commonly known as a
  10504. ``container'', typically created by the @command{guix environment}
  10505. (@pxref{Invoking guix environment}) and @command{guix system container}
  10506. (@pxref{Invoking guix system}) commands.
  10507. The general syntax is:
  10508. @example
  10509. guix container @var{action} @var{options}@dots{}
  10510. @end example
  10511. @var{action} specifies the operation to perform with a container, and
  10512. @var{options} specifies the context-specific arguments for the action.
  10513. The following actions are available:
  10514. @table @code
  10515. @item exec
  10516. Execute a command within the context of a running container.
  10517. The syntax is:
  10518. @example
  10519. guix container exec @var{pid} @var{program} @var{arguments}@dots{}
  10520. @end example
  10521. @var{pid} specifies the process ID of the running container.
  10522. @var{program} specifies an executable file name within the root file
  10523. system of the container. @var{arguments} are the additional options that
  10524. will be passed to @var{program}.
  10525. The following command launches an interactive login shell inside a
  10526. Guix system container, started by @command{guix system container}, and whose
  10527. process ID is 9001:
  10528. @example
  10529. guix container exec 9001 /run/current-system/profile/bin/bash --login
  10530. @end example
  10531. Note that the @var{pid} cannot be the parent process of a container. It
  10532. must be PID 1 of the container or one of its child processes.
  10533. @end table
  10534. @node Invoking guix weather
  10535. @section Invoking @command{guix weather}
  10536. Occasionally you're grumpy because substitutes are lacking and you end
  10537. up building packages by yourself (@pxref{Substitutes}). The
  10538. @command{guix weather} command reports on substitute availability on the
  10539. specified servers so you can have an idea of whether you'll be grumpy
  10540. today. It can sometimes be useful info as a user, but it is primarily
  10541. useful to people running @command{guix publish} (@pxref{Invoking guix
  10542. publish}).
  10543. @cindex statistics, for substitutes
  10544. @cindex availability of substitutes
  10545. @cindex substitute availability
  10546. @cindex weather, substitute availability
  10547. Here's a sample run:
  10548. @example
  10549. $ guix weather --substitute-urls=https://guix.example.org
  10550. computing 5,872 package derivations for x86_64-linux...
  10551. looking for 6,128 store items on https://guix.example.org..
  10552. updating list of substitutes from 'https://guix.example.org'... 100.0%
  10553. https://guix.example.org
  10554. 43.4% substitutes available (2,658 out of 6,128)
  10555. 7,032.5 MiB of nars (compressed)
  10556. 19,824.2 MiB on disk (uncompressed)
  10557. 0.030 seconds per request (182.9 seconds in total)
  10558. 33.5 requests per second
  10559. 9.8% (342 out of 3,470) of the missing items are queued
  10560. 867 queued builds
  10561. x86_64-linux: 518 (59.7%)
  10562. i686-linux: 221 (25.5%)
  10563. aarch64-linux: 128 (14.8%)
  10564. build rate: 23.41 builds per hour
  10565. x86_64-linux: 11.16 builds per hour
  10566. i686-linux: 6.03 builds per hour
  10567. aarch64-linux: 6.41 builds per hour
  10568. @end example
  10569. @cindex continuous integration, statistics
  10570. As you can see, it reports the fraction of all the packages for which
  10571. substitutes are available on the server---regardless of whether
  10572. substitutes are enabled, and regardless of whether this server's signing
  10573. key is authorized. It also reports the size of the compressed archives
  10574. (``nars'') provided by the server, the size the corresponding store
  10575. items occupy in the store (assuming deduplication is turned off), and
  10576. the server's throughput. The second part gives continuous integration
  10577. (CI) statistics, if the server supports it. In addition, using the
  10578. @option{--coverage} option, @command{guix weather} can list ``important''
  10579. package substitutes missing on the server (see below).
  10580. To achieve that, @command{guix weather} queries over HTTP(S) meta-data
  10581. (@dfn{narinfos}) for all the relevant store items. Like @command{guix
  10582. challenge}, it ignores signatures on those substitutes, which is
  10583. innocuous since the command only gathers statistics and cannot install
  10584. those substitutes.
  10585. The general syntax is:
  10586. @example
  10587. guix weather @var{options}@dots{} [@var{packages}@dots{}]
  10588. @end example
  10589. When @var{packages} is omitted, @command{guix weather} checks the availability
  10590. of substitutes for @emph{all} the packages, or for those specified with
  10591. @option{--manifest}; otherwise it only considers the specified packages. It
  10592. is also possible to query specific system types with @option{--system}.
  10593. @command{guix weather} exits with a non-zero code when the fraction of
  10594. available substitutes is below 100%.
  10595. The available options are listed below.
  10596. @table @code
  10597. @item --substitute-urls=@var{urls}
  10598. @var{urls} is the space-separated list of substitute server URLs to
  10599. query. When this option is omitted, the default set of substitute
  10600. servers is queried.
  10601. @item --system=@var{system}
  10602. @itemx -s @var{system}
  10603. Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
  10604. option can be repeated, in which case @command{guix weather} will query
  10605. substitutes for several system types.
  10606. @item --manifest=@var{file}
  10607. Instead of querying substitutes for all the packages, only ask for those
  10608. specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
  10609. with the @code{-m} option of @command{guix package} (@pxref{Invoking
  10610. guix package}).
  10611. This option can be repeated several times, in which case the manifests
  10612. are concatenated.
  10613. @item --coverage[=@var{count}]
  10614. @itemx -c [@var{count}]
  10615. Report on substitute coverage for packages: list packages with at least
  10616. @var{count} dependents (zero by default) for which substitutes are
  10617. unavailable. Dependent packages themselves are not listed: if @var{b} depends
  10618. on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
  10619. @var{b} usually lacks substitutes as well. The result looks like this:
  10620. @example
  10621. $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
  10622. computing 8,983 package derivations for x86_64-linux...
  10623. looking for 9,343 store items on @value{SUBSTITUTE-URL}...
  10624. updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
  10625. @value{SUBSTITUTE-URL}
  10626. 64.7% substitutes available (6,047 out of 9,343)
  10627. @dots{}
  10628. 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
  10629. 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
  10630. 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
  10631. 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
  10632. @dots{}
  10633. @end example
  10634. What this example shows is that @code{kcoreaddons} and presumably the 58
  10635. packages that depend on it have no substitutes at
  10636. @code{@value{SUBSTITUTE-SERVER}}; likewise for @code{qgpgme} and the 46
  10637. packages that depend on it.
  10638. If you are a Guix developer, or if you are taking care of this build farm,
  10639. you'll probably want to have a closer look at these packages: they may simply
  10640. fail to build.
  10641. @item --display-missing
  10642. Display the list of store items for which substitutes are missing.
  10643. @end table
  10644. @node Invoking guix processes
  10645. @section Invoking @command{guix processes}
  10646. The @command{guix processes} command can be useful to developers and system
  10647. administrators, especially on multi-user machines and on build farms: it lists
  10648. the current sessions (connections to the daemon), as well as information about
  10649. the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
  10650. started with @option{--listen} specifying a TCP endpoint, are @emph{not}
  10651. listed.}. Here's an example of the information it returns:
  10652. @example
  10653. $ sudo guix processes
  10654. SessionPID: 19002
  10655. ClientPID: 19090
  10656. ClientCommand: guix environment --ad-hoc python
  10657. SessionPID: 19402
  10658. ClientPID: 19367
  10659. ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
  10660. SessionPID: 19444
  10661. ClientPID: 19419
  10662. ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
  10663. LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
  10664. LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
  10665. LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
  10666. ChildPID: 20495
  10667. ChildCommand: guix offload x86_64-linux 7200 1 28800
  10668. ChildPID: 27733
  10669. ChildCommand: guix offload x86_64-linux 7200 1 28800
  10670. ChildPID: 27793
  10671. ChildCommand: guix offload x86_64-linux 7200 1 28800
  10672. @end example
  10673. In this example we see that @command{guix-daemon} has three clients:
  10674. @command{guix environment}, @command{guix publish}, and the Cuirass continuous
  10675. integration tool; their process identifier (PID) is given by the
  10676. @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
  10677. @command{guix-daemon} sub-process of this particular session.
  10678. The @code{LockHeld} fields show which store items are currently locked
  10679. by this session, which corresponds to store items being built or
  10680. substituted (the @code{LockHeld} field is not displayed when
  10681. @command{guix processes} is not running as root). Last, by looking at
  10682. the @code{ChildPID} and @code{ChildCommand} fields, we understand that
  10683. these three builds are being offloaded (@pxref{Daemon Offload Setup}).
  10684. The output is in Recutils format so we can use the handy @command{recsel}
  10685. command to select sessions of interest (@pxref{Selection Expressions,,,
  10686. recutils, GNU recutils manual}). As an example, the command shows the command
  10687. line and PID of the client that triggered the build of a Perl package:
  10688. @example
  10689. $ sudo guix processes | \
  10690. recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
  10691. ClientPID: 19419
  10692. ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
  10693. @end example
  10694. Additional options are listed below.
  10695. @table @code
  10696. @item --format=@var{format}
  10697. @itemx -f @var{format}
  10698. Produce output in the specified @var{format}, one of:
  10699. @table @code
  10700. @item recutils
  10701. The default option. It outputs a set of Session recutils records
  10702. that include each @code{ChildProcess} as a field.
  10703. @item normalized
  10704. Normalize the output records into record sets (@pxref{Record Sets,,,
  10705. recutils, GNU recutils manual}). Normalizing into record sets allows
  10706. joins across record types. The example below lists the PID of each
  10707. @code{ChildProcess} and the associated PID for @code{Session} that
  10708. spawned the @code{ChildProcess} where the @code{Session} was started
  10709. using @command{guix build}.
  10710. @example
  10711. $ guix processes --format=normalized | \
  10712. recsel \
  10713. -j Session \
  10714. -t ChildProcess \
  10715. -p Session.PID,PID \
  10716. -e 'Session.ClientCommand ~ "guix build"'
  10717. PID: 4435
  10718. Session_PID: 4278
  10719. PID: 4554
  10720. Session_PID: 4278
  10721. PID: 4646
  10722. Session_PID: 4278
  10723. @end example
  10724. @end table
  10725. @end table
  10726. @node System Configuration
  10727. @chapter System Configuration
  10728. @cindex system configuration
  10729. Guix System supports a consistent whole-system configuration
  10730. mechanism. By that we mean that all aspects of the global system
  10731. configuration---such as the available system services, timezone and
  10732. locale settings, user accounts---are declared in a single place. Such
  10733. a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
  10734. One of the advantages of putting all the system configuration under the
  10735. control of Guix is that it supports transactional system upgrades, and
  10736. makes it possible to roll back to a previous system instantiation,
  10737. should something go wrong with the new one (@pxref{Features}). Another
  10738. advantage is that it makes it easy to replicate the exact same configuration
  10739. across different machines, or at different points in time, without
  10740. having to resort to additional administration tools layered on top of
  10741. the own tools of the system.
  10742. @c Yes, we're talking of Puppet, Chef, & co. here. ↑
  10743. This section describes this mechanism. First we focus on the system
  10744. administrator's viewpoint---explaining how the system is configured and
  10745. instantiated. Then we show how this mechanism can be extended, for
  10746. instance to support new system services.
  10747. @menu
  10748. * Using the Configuration System:: Customizing your GNU system.
  10749. * operating-system Reference:: Detail of operating-system declarations.
  10750. * File Systems:: Configuring file system mounts.
  10751. * Mapped Devices:: Block device extra processing.
  10752. * User Accounts:: Specifying user accounts.
  10753. * Keyboard Layout:: How the system interprets key strokes.
  10754. * Locales:: Language and cultural convention settings.
  10755. * Services:: Specifying system services.
  10756. * Setuid Programs:: Programs running with root privileges.
  10757. * X.509 Certificates:: Authenticating HTTPS servers.
  10758. * Name Service Switch:: Configuring libc's name service switch.
  10759. * Initial RAM Disk:: Linux-Libre bootstrapping.
  10760. * Bootloader Configuration:: Configuring the boot loader.
  10761. * Invoking guix system:: Instantiating a system configuration.
  10762. * Invoking guix deploy:: Deploying a system configuration to a remote host.
  10763. * Running Guix in a VM:: How to run Guix System in a virtual machine.
  10764. * Defining Services:: Adding new service definitions.
  10765. @end menu
  10766. @node Using the Configuration System
  10767. @section Using the Configuration System
  10768. The operating system is configured by providing an
  10769. @code{operating-system} declaration in a file that can then be passed to
  10770. the @command{guix system} command (@pxref{Invoking guix system}). A
  10771. simple setup, with the default system services, the default Linux-Libre
  10772. kernel, initial RAM disk, and boot loader looks like this:
  10773. @findex operating-system
  10774. @lisp
  10775. @include os-config-bare-bones.texi
  10776. @end lisp
  10777. This example should be self-describing. Some of the fields defined
  10778. above, such as @code{host-name} and @code{bootloader}, are mandatory.
  10779. Others, such as @code{packages} and @code{services}, can be omitted, in
  10780. which case they get a default value.
  10781. Below we discuss the effect of some of the most important fields
  10782. (@pxref{operating-system Reference}, for details about all the available
  10783. fields), and how to @dfn{instantiate} the operating system using
  10784. @command{guix system}.
  10785. @unnumberedsubsec Bootloader
  10786. @cindex legacy boot, on Intel machines
  10787. @cindex BIOS boot, on Intel machines
  10788. @cindex UEFI boot
  10789. @cindex EFI boot
  10790. The @code{bootloader} field describes the method that will be used to boot
  10791. your system. Machines based on Intel processors can boot in ``legacy'' BIOS
  10792. mode, as in the example above. However, more recent machines rely instead on
  10793. the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
  10794. the @code{bootloader} field should contain something along these lines:
  10795. @lisp
  10796. (bootloader-configuration
  10797. (bootloader grub-efi-bootloader)
  10798. (target "/boot/efi"))
  10799. @end lisp
  10800. @xref{Bootloader Configuration}, for more information on the available
  10801. configuration options.
  10802. @unnumberedsubsec Globally-Visible Packages
  10803. @vindex %base-packages
  10804. The @code{packages} field lists packages that will be globally visible
  10805. on the system, for all user accounts---i.e., in every user's @env{PATH}
  10806. environment variable---in addition to the per-user profiles
  10807. (@pxref{Invoking guix package}). The @code{%base-packages} variable
  10808. provides all the tools one would expect for basic user and administrator
  10809. tasks---including the GNU Core Utilities, the GNU Networking Utilities,
  10810. the GNU Zile lightweight text editor, @command{find}, @command{grep},
  10811. etc. The example above adds GNU@tie{}Screen to those,
  10812. taken from the @code{(gnu packages screen)}
  10813. module (@pxref{Package Modules}). The
  10814. @code{(list package output)} syntax can be used to add a specific output
  10815. of a package:
  10816. @lisp
  10817. (use-modules (gnu packages))
  10818. (use-modules (gnu packages dns))
  10819. (operating-system
  10820. ;; ...
  10821. (packages (cons (list bind "utils")
  10822. %base-packages)))
  10823. @end lisp
  10824. @findex specification->package
  10825. Referring to packages by variable name, like @code{bind} above, has
  10826. the advantage of being unambiguous; it also allows typos and such to be
  10827. diagnosed right away as ``unbound variables''. The downside is that one
  10828. needs to know which module defines which package, and to augment the
  10829. @code{use-package-modules} line accordingly. To avoid that, one can use
  10830. the @code{specification->package} procedure of the @code{(gnu packages)}
  10831. module, which returns the best package for a given name or name and
  10832. version:
  10833. @lisp
  10834. (use-modules (gnu packages))
  10835. (operating-system
  10836. ;; ...
  10837. (packages (append (map specification->package
  10838. '("tcpdump" "htop" "gnupg@@2.0"))
  10839. %base-packages)))
  10840. @end lisp
  10841. @unnumberedsubsec System Services
  10842. @cindex services
  10843. @vindex %base-services
  10844. The @code{services} field lists @dfn{system services} to be made
  10845. available when the system starts (@pxref{Services}).
  10846. The @code{operating-system} declaration above specifies that, in
  10847. addition to the basic services, we want the OpenSSH secure shell
  10848. daemon listening on port 2222 (@pxref{Networking Services,
  10849. @code{openssh-service-type}}). Under the hood,
  10850. @code{openssh-service-type} arranges so that @command{sshd} is started with the
  10851. right command-line options, possibly with supporting configuration files
  10852. generated as needed (@pxref{Defining Services}).
  10853. @cindex customization, of services
  10854. @findex modify-services
  10855. Occasionally, instead of using the base services as is, you will want to
  10856. customize them. To do this, use @code{modify-services} (@pxref{Service
  10857. Reference, @code{modify-services}}) to modify the list.
  10858. For example, suppose you want to modify @code{guix-daemon} and Mingetty
  10859. (the console log-in) in the @code{%base-services} list (@pxref{Base
  10860. Services, @code{%base-services}}). To do that, you can write the
  10861. following in your operating system declaration:
  10862. @lisp
  10863. (define %my-services
  10864. ;; My very own list of services.
  10865. (modify-services %base-services
  10866. (guix-service-type config =>
  10867. (guix-configuration
  10868. (inherit config)
  10869. ;; Fetch substitutes from example.org.
  10870. (substitute-urls
  10871. (list "https://example.org/guix"
  10872. "https://ci.guix.gnu.org"))))
  10873. (mingetty-service-type config =>
  10874. (mingetty-configuration
  10875. (inherit config)
  10876. ;; Automatially log in as "guest".
  10877. (auto-login "guest")))))
  10878. (operating-system
  10879. ;; @dots{}
  10880. (services %my-services))
  10881. @end lisp
  10882. This changes the configuration---i.e., the service parameters---of the
  10883. @code{guix-service-type} instance, and that of all the
  10884. @code{mingetty-service-type} instances in the @code{%base-services} list.
  10885. Observe how this is accomplished: first, we arrange for the original
  10886. configuration to be bound to the identifier @code{config} in the
  10887. @var{body}, and then we write the @var{body} so that it evaluates to the
  10888. desired configuration. In particular, notice how we use @code{inherit}
  10889. to create a new configuration which has the same values as the old
  10890. configuration, but with a few modifications.
  10891. @cindex encrypted disk
  10892. The configuration for a typical ``desktop'' usage, with an encrypted
  10893. root partition, the X11 display
  10894. server, GNOME and Xfce (users can choose which of these desktop
  10895. environments to use at the log-in screen by pressing @kbd{F1}), network
  10896. management, power management, and more, would look like this:
  10897. @lisp
  10898. @include os-config-desktop.texi
  10899. @end lisp
  10900. A graphical system with a choice of lightweight window managers
  10901. instead of full-blown desktop environments would look like this:
  10902. @lisp
  10903. @include os-config-lightweight-desktop.texi
  10904. @end lisp
  10905. This example refers to the @file{/boot/efi} file system by its UUID,
  10906. @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
  10907. as returned by the @command{blkid} command.
  10908. @xref{Desktop Services}, for the exact list of services provided by
  10909. @code{%desktop-services}. @xref{X.509 Certificates}, for background
  10910. information about the @code{nss-certs} package that is used here.
  10911. Again, @code{%desktop-services} is just a list of service objects. If
  10912. you want to remove services from there, you can do so using the
  10913. procedures for list filtering (@pxref{SRFI-1 Filtering and
  10914. Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
  10915. following expression returns a list that contains all the services in
  10916. @code{%desktop-services} minus the Avahi service:
  10917. @lisp
  10918. (remove (lambda (service)
  10919. (eq? (service-kind service) avahi-service-type))
  10920. %desktop-services)
  10921. @end lisp
  10922. @unnumberedsubsec Instantiating the System
  10923. Assuming the @code{operating-system} declaration
  10924. is stored in the @file{my-system-config.scm}
  10925. file, the @command{guix system reconfigure my-system-config.scm} command
  10926. instantiates that configuration, and makes it the default GRUB boot
  10927. entry (@pxref{Invoking guix system}).
  10928. The normal way to change the system configuration is by updating this
  10929. file and re-running @command{guix system reconfigure}. One should never
  10930. have to touch files in @file{/etc} or to run commands that modify the
  10931. system state such as @command{useradd} or @command{grub-install}. In
  10932. fact, you must avoid that since that would not only void your warranty
  10933. but also prevent you from rolling back to previous versions of your
  10934. system, should you ever need to.
  10935. @cindex roll-back, of the operating system
  10936. Speaking of roll-back, each time you run @command{guix system
  10937. reconfigure}, a new @dfn{generation} of the system is created---without
  10938. modifying or deleting previous generations. Old system generations get
  10939. an entry in the bootloader boot menu, allowing you to boot them in case
  10940. something went wrong with the latest generation. Reassuring, no? The
  10941. @command{guix system list-generations} command lists the system
  10942. generations available on disk. It is also possible to roll back the
  10943. system via the commands @command{guix system roll-back} and
  10944. @command{guix system switch-generation}.
  10945. Although the @command{guix system reconfigure} command will not modify
  10946. previous generations, you must take care when the current generation is not
  10947. the latest (e.g., after invoking @command{guix system roll-back}), since
  10948. the operation might overwrite a later generation (@pxref{Invoking guix
  10949. system}).
  10950. @unnumberedsubsec The Programming Interface
  10951. At the Scheme level, the bulk of an @code{operating-system} declaration
  10952. is instantiated with the following monadic procedure (@pxref{The Store
  10953. Monad}):
  10954. @deffn {Monadic Procedure} operating-system-derivation os
  10955. Return a derivation that builds @var{os}, an @code{operating-system}
  10956. object (@pxref{Derivations}).
  10957. The output of the derivation is a single directory that refers to all
  10958. the packages, configuration files, and other supporting files needed to
  10959. instantiate @var{os}.
  10960. @end deffn
  10961. This procedure is provided by the @code{(gnu system)} module. Along
  10962. with @code{(gnu services)} (@pxref{Services}), this module contains the
  10963. guts of Guix System. Make sure to visit it!
  10964. @node operating-system Reference
  10965. @section @code{operating-system} Reference
  10966. This section summarizes all the options available in
  10967. @code{operating-system} declarations (@pxref{Using the Configuration
  10968. System}).
  10969. @deftp {Data Type} operating-system
  10970. This is the data type representing an operating system configuration.
  10971. By that, we mean all the global system configuration, not per-user
  10972. configuration (@pxref{Using the Configuration System}).
  10973. @table @asis
  10974. @item @code{kernel} (default: @code{linux-libre})
  10975. The package object of the operating system kernel to
  10976. use@footnote{Currently only the Linux-libre kernel is fully supported.
  10977. Using GNU@tie{}mach with the GNU@tie{}Hurd is experimental and only
  10978. available when building a virtual machine disk image.}.
  10979. @cindex hurd
  10980. @item @code{hurd} (default: @code{#f})
  10981. The package object of the Hurd to be started by the kernel. When this
  10982. field is set, produce a GNU/Hurd operating system. In that case,
  10983. @code{kernel} must also be set to the @code{gnumach} package---the
  10984. microkernel the Hurd runs on.
  10985. @quotation Warning
  10986. This feature is experimental and only supported for disk images.
  10987. @end quotation
  10988. @item @code{kernel-loadable-modules} (default: '())
  10989. A list of objects (usually packages) to collect loadable kernel modules
  10990. from--e.g. @code{(list ddcci-driver-linux)}.
  10991. @item @code{kernel-arguments} (default: @code{%default-kernel-arguments})
  10992. List of strings or gexps representing additional arguments to pass on
  10993. the command-line of the kernel---e.g., @code{("console=ttyS0")}.
  10994. @item @code{bootloader}
  10995. The system bootloader configuration object. @xref{Bootloader Configuration}.
  10996. @item @code{label}
  10997. This is the label (a string) as it appears in the bootloader's menu entry.
  10998. The default label includes the kernel name and version.
  10999. @item @code{keyboard-layout} (default: @code{#f})
  11000. This field specifies the keyboard layout to use in the console. It can be
  11001. either @code{#f}, in which case the default keyboard layout is used (usually
  11002. US English), or a @code{<keyboard-layout>} record. @xref{Keyboard Layout},
  11003. for more information.
  11004. This keyboard layout is in effect as soon as the kernel has booted. For
  11005. instance, it is the keyboard layout in effect when you type a passphrase if
  11006. your root file system is on a @code{luks-device-mapping} mapped device
  11007. (@pxref{Mapped Devices}).
  11008. @quotation Note
  11009. This does @emph{not} specify the keyboard layout used by the bootloader, nor
  11010. that used by the graphical display server. @xref{Bootloader Configuration},
  11011. for information on how to specify the bootloader's keyboard layout. @xref{X
  11012. Window}, for information on how to specify the keyboard layout used by the X
  11013. Window System.
  11014. @end quotation
  11015. @item @code{initrd-modules} (default: @code{%base-initrd-modules})
  11016. @cindex initrd
  11017. @cindex initial RAM disk
  11018. The list of Linux kernel modules that need to be available in the
  11019. initial RAM disk. @xref{Initial RAM Disk}.
  11020. @item @code{initrd} (default: @code{base-initrd})
  11021. A procedure that returns an initial RAM disk for the Linux
  11022. kernel. This field is provided to support low-level customization and
  11023. should rarely be needed for casual use. @xref{Initial RAM Disk}.
  11024. @item @code{firmware} (default: @code{%base-firmware})
  11025. @cindex firmware
  11026. List of firmware packages loadable by the operating system kernel.
  11027. The default includes firmware needed for Atheros- and Broadcom-based
  11028. WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
  11029. respectively). @xref{Hardware Considerations}, for more info on
  11030. supported hardware.
  11031. @item @code{host-name}
  11032. The host name.
  11033. @item @code{hosts-file}
  11034. @cindex hosts file
  11035. A file-like object (@pxref{G-Expressions, file-like objects}) for use as
  11036. @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
  11037. Reference Manual}). The default is a file with entries for
  11038. @code{localhost} and @var{host-name}.
  11039. @item @code{mapped-devices} (default: @code{'()})
  11040. A list of mapped devices. @xref{Mapped Devices}.
  11041. @item @code{file-systems}
  11042. A list of file systems. @xref{File Systems}.
  11043. @cindex swap devices
  11044. @cindex swap space
  11045. @item @code{swap-devices} (default: @code{'()})
  11046. A list of UUIDs, file system labels, or strings identifying devices or
  11047. files to be used for ``swap
  11048. space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
  11049. Manual}). Here are some examples:
  11050. @table @code
  11051. @item (list (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb"))
  11052. Use the swap partition with the given UUID@. You can learn the UUID of a
  11053. Linux swap partition by running @command{swaplabel @var{device}}, where
  11054. @var{device} is the @file{/dev} file name of that partition.
  11055. @item (list (file-system-label "swap"))
  11056. Use the partition with label @code{swap}. Again, the
  11057. @command{swaplabel} command allows you to view and change the label of a
  11058. Linux swap partition.
  11059. @item (list "/swapfile")
  11060. Use the file @file{/swapfile} as swap space.
  11061. @item (list "/dev/sda3" "/dev/sdb2")
  11062. Use the @file{/dev/sda3} and @file{/dev/sdb2} partitions as swap space.
  11063. We recommend referring to swap devices by UUIDs or labels as shown above
  11064. instead.
  11065. @end table
  11066. It is possible to specify a swap file in a file system on a mapped
  11067. device (under @file{/dev/mapper}), provided that the necessary device
  11068. mapping and file system are also specified. @xref{Mapped Devices} and
  11069. @ref{File Systems}.
  11070. @item @code{users} (default: @code{%base-user-accounts})
  11071. @itemx @code{groups} (default: @code{%base-groups})
  11072. List of user accounts and groups. @xref{User Accounts}.
  11073. If the @code{users} list lacks a user account with UID@tie{}0, a
  11074. ``root'' account with UID@tie{}0 is automatically added.
  11075. @item @code{skeletons} (default: @code{(default-skeletons)})
  11076. A list of target file name/file-like object tuples (@pxref{G-Expressions,
  11077. file-like objects}). These are the skeleton files that will be added to
  11078. the home directory of newly-created user accounts.
  11079. For instance, a valid value may look like this:
  11080. @lisp
  11081. `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
  11082. (".guile" ,(plain-file "guile"
  11083. "(use-modules (ice-9 readline))
  11084. (activate-readline)")))
  11085. @end lisp
  11086. @item @code{issue} (default: @code{%default-issue})
  11087. A string denoting the contents of the @file{/etc/issue} file, which is
  11088. displayed when users log in on a text console.
  11089. @item @code{packages} (default: @code{%base-packages})
  11090. A list of packages to be installed in the global profile, which is accessible
  11091. at @file{/run/current-system/profile}. Each element is either a package
  11092. variable or a package/output tuple. Here's a simple example of both:
  11093. @lisp
  11094. (cons* git ; the default "out" output
  11095. (list git "send-email") ; another output of git
  11096. %base-packages) ; the default set
  11097. @end lisp
  11098. The default set includes core utilities and it is good practice to
  11099. install non-core utilities in user profiles (@pxref{Invoking guix
  11100. package}).
  11101. @item @code{timezone}
  11102. A timezone identifying string---e.g., @code{"Europe/Paris"}.
  11103. You can run the @command{tzselect} command to find out which timezone
  11104. string corresponds to your region. Choosing an invalid timezone name
  11105. causes @command{guix system} to fail.
  11106. @item @code{locale} (default: @code{"en_US.utf8"})
  11107. The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
  11108. Library Reference Manual}). @xref{Locales}, for more information.
  11109. @item @code{locale-definitions} (default: @code{%default-locale-definitions})
  11110. The list of locale definitions to be compiled and that may be used at
  11111. run time. @xref{Locales}.
  11112. @item @code{locale-libcs} (default: @code{(list @var{glibc})})
  11113. The list of GNU@tie{}libc packages whose locale data and tools are used
  11114. to build the locale definitions. @xref{Locales}, for compatibility
  11115. considerations that justify this option.
  11116. @item @code{name-service-switch} (default: @code{%default-nss})
  11117. Configuration of the libc name service switch (NSS)---a
  11118. @code{<name-service-switch>} object. @xref{Name Service Switch}, for
  11119. details.
  11120. @item @code{services} (default: @code{%base-services})
  11121. A list of service objects denoting system services. @xref{Services}.
  11122. @cindex essential services
  11123. @item @code{essential-services} (default: ...)
  11124. The list of ``essential services''---i.e., things like instances of
  11125. @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
  11126. Reference}), which are derived from the operating system definition itself.
  11127. As a user you should @emph{never} need to touch this field.
  11128. @item @code{pam-services} (default: @code{(base-pam-services)})
  11129. @cindex PAM
  11130. @cindex pluggable authentication modules
  11131. Linux @dfn{pluggable authentication module} (PAM) services.
  11132. @c FIXME: Add xref to PAM services section.
  11133. @item @code{setuid-programs} (default: @code{%setuid-programs})
  11134. List of string-valued G-expressions denoting setuid programs.
  11135. @xref{Setuid Programs}.
  11136. @item @code{sudoers-file} (default: @code{%sudoers-specification})
  11137. @cindex sudoers file
  11138. The contents of the @file{/etc/sudoers} file as a file-like object
  11139. (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
  11140. This file specifies which users can use the @command{sudo} command, what
  11141. they are allowed to do, and what privileges they may gain. The default
  11142. is that only @code{root} and members of the @code{wheel} group may use
  11143. @code{sudo}.
  11144. @end table
  11145. @deffn {Scheme Syntax} this-operating-system
  11146. When used in the @emph{lexical scope} of an operating system field definition,
  11147. this identifier resolves to the operating system being defined.
  11148. The example below shows how to refer to the operating system being defined in
  11149. the definition of the @code{label} field:
  11150. @lisp
  11151. (use-modules (gnu) (guix))
  11152. (operating-system
  11153. ;; ...
  11154. (label (package-full-name
  11155. (operating-system-kernel this-operating-system))))
  11156. @end lisp
  11157. It is an error to refer to @code{this-operating-system} outside an operating
  11158. system definition.
  11159. @end deffn
  11160. @end deftp
  11161. @node File Systems
  11162. @section File Systems
  11163. The list of file systems to be mounted is specified in the
  11164. @code{file-systems} field of the operating system declaration
  11165. (@pxref{Using the Configuration System}). Each file system is declared
  11166. using the @code{file-system} form, like this:
  11167. @lisp
  11168. (file-system
  11169. (mount-point "/home")
  11170. (device "/dev/sda3")
  11171. (type "ext4"))
  11172. @end lisp
  11173. As usual, some of the fields are mandatory---those shown in the example
  11174. above---while others can be omitted. These are described below.
  11175. @deftp {Data Type} file-system
  11176. Objects of this type represent file systems to be mounted. They
  11177. contain the following members:
  11178. @table @asis
  11179. @item @code{type}
  11180. This is a string specifying the type of the file system---e.g.,
  11181. @code{"ext4"}.
  11182. @item @code{mount-point}
  11183. This designates the place where the file system is to be mounted.
  11184. @item @code{device}
  11185. This names the ``source'' of the file system. It can be one of three
  11186. things: a file system label, a file system UUID, or the name of a
  11187. @file{/dev} node. Labels and UUIDs offer a way to refer to file
  11188. systems without having to hard-code their actual device
  11189. name@footnote{Note that, while it is tempting to use
  11190. @file{/dev/disk/by-uuid} and similar device names to achieve the same
  11191. result, this is not recommended: These special device nodes are created
  11192. by the udev daemon and may be unavailable at the time the device is
  11193. mounted.}.
  11194. @findex file-system-label
  11195. File system labels are created using the @code{file-system-label}
  11196. procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
  11197. plain strings. Here's an example of a file system referred to by its
  11198. label, as shown by the @command{e2label} command:
  11199. @lisp
  11200. (file-system
  11201. (mount-point "/home")
  11202. (type "ext4")
  11203. (device (file-system-label "my-home")))
  11204. @end lisp
  11205. @findex uuid
  11206. UUIDs are converted from their string representation (as shown by the
  11207. @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
  11208. @code{uuid} form expects 16-byte UUIDs as defined in
  11209. @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
  11210. form of UUID used by the ext2 family of file systems and others, but it
  11211. is different from ``UUIDs'' found in FAT file systems, for instance.},
  11212. like this:
  11213. @lisp
  11214. (file-system
  11215. (mount-point "/home")
  11216. (type "ext4")
  11217. (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
  11218. @end lisp
  11219. When the source of a file system is a mapped device (@pxref{Mapped
  11220. Devices}), its @code{device} field @emph{must} refer to the mapped
  11221. device name---e.g., @file{"/dev/mapper/root-partition"}.
  11222. This is required so that
  11223. the system knows that mounting the file system depends on having the
  11224. corresponding device mapping established.
  11225. @item @code{flags} (default: @code{'()})
  11226. This is a list of symbols denoting mount flags. Recognized flags
  11227. include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
  11228. access to special files), @code{no-suid} (ignore setuid and setgid
  11229. bits), @code{no-atime} (do not update file access times),
  11230. @code{strict-atime} (update file access time), @code{lazy-time} (only
  11231. update time on the in-memory version of the file inode), and
  11232. @code{no-exec} (disallow program execution).
  11233. @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
  11234. Manual}, for more information on these flags.
  11235. @item @code{options} (default: @code{#f})
  11236. This is either @code{#f}, or a string denoting mount options passed to
  11237. the file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C
  11238. Library Reference Manual}, for details and run @command{man 8 mount} for
  11239. options for various file systems. Note that the
  11240. @code{file-system-options->alist} and @code{alist->file-system-options}
  11241. procedures from @code{(gnu system file-systems)} can be used to convert
  11242. file system options given as an association list to the string
  11243. representation, and vice-versa.
  11244. @item @code{mount?} (default: @code{#t})
  11245. This value indicates whether to automatically mount the file system when
  11246. the system is brought up. When set to @code{#f}, the file system gets
  11247. an entry in @file{/etc/fstab} (read by the @command{mount} command) but
  11248. is not automatically mounted.
  11249. @item @code{needed-for-boot?} (default: @code{#f})
  11250. This Boolean value indicates whether the file system is needed when
  11251. booting. If that is true, then the file system is mounted when the
  11252. initial RAM disk (initrd) is loaded. This is always the case, for
  11253. instance, for the root file system.
  11254. @item @code{check?} (default: @code{#t})
  11255. This Boolean indicates whether the file system needs to be checked for
  11256. errors before being mounted.
  11257. @item @code{create-mount-point?} (default: @code{#f})
  11258. When true, the mount point is created if it does not exist yet.
  11259. @item @code{mount-may-fail?} (default: @code{#f})
  11260. When true, this indicates that mounting this file system can fail but
  11261. that should not be considered an error. This is useful in unusual
  11262. cases; an example of this is @code{efivarfs}, a file system that can
  11263. only be mounted on EFI/UEFI systems.
  11264. @item @code{dependencies} (default: @code{'()})
  11265. This is a list of @code{<file-system>} or @code{<mapped-device>} objects
  11266. representing file systems that must be mounted or mapped devices that
  11267. must be opened before (and unmounted or closed after) this one.
  11268. As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
  11269. a dependency of @file{/sys/fs/cgroup/cpu} and
  11270. @file{/sys/fs/cgroup/memory}.
  11271. Another example is a file system that depends on a mapped device, for
  11272. example for an encrypted partition (@pxref{Mapped Devices}).
  11273. @end table
  11274. @end deftp
  11275. @deffn {Scheme Procedure} file-system-label @var{str}
  11276. This procedure returns an opaque file system label from @var{str}, a
  11277. string:
  11278. @lisp
  11279. (file-system-label "home")
  11280. @result{} #<file-system-label "home">
  11281. @end lisp
  11282. File system labels are used to refer to file systems by label rather
  11283. than by device name. See above for examples.
  11284. @end deffn
  11285. The @code{(gnu system file-systems)} exports the following useful
  11286. variables.
  11287. @defvr {Scheme Variable} %base-file-systems
  11288. These are essential file systems that are required on normal systems,
  11289. such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
  11290. below). Operating system declarations should always contain at least
  11291. these.
  11292. @end defvr
  11293. @defvr {Scheme Variable} %pseudo-terminal-file-system
  11294. This is the file system to be mounted as @file{/dev/pts}. It supports
  11295. @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
  11296. functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
  11297. Manual}). Pseudo-terminals are used by terminal emulators such as
  11298. @command{xterm}.
  11299. @end defvr
  11300. @defvr {Scheme Variable} %shared-memory-file-system
  11301. This file system is mounted as @file{/dev/shm} and is used to support
  11302. memory sharing across processes (@pxref{Memory-mapped I/O,
  11303. @code{shm_open},, libc, The GNU C Library Reference Manual}).
  11304. @end defvr
  11305. @defvr {Scheme Variable} %immutable-store
  11306. This file system performs a read-only ``bind mount'' of
  11307. @file{/gnu/store}, making it read-only for all the users including
  11308. @code{root}. This prevents against accidental modification by software
  11309. running as @code{root} or by system administrators.
  11310. The daemon itself is still able to write to the store: it remounts it
  11311. read-write in its own ``name space.''
  11312. @end defvr
  11313. @defvr {Scheme Variable} %binary-format-file-system
  11314. The @code{binfmt_misc} file system, which allows handling of arbitrary
  11315. executable file types to be delegated to user space. This requires the
  11316. @code{binfmt.ko} kernel module to be loaded.
  11317. @end defvr
  11318. @defvr {Scheme Variable} %fuse-control-file-system
  11319. The @code{fusectl} file system, which allows unprivileged users to mount
  11320. and unmount user-space FUSE file systems. This requires the
  11321. @code{fuse.ko} kernel module to be loaded.
  11322. @end defvr
  11323. The @code{(gnu system uuid)} module provides tools to deal with file
  11324. system ``unique identifiers'' (UUIDs).
  11325. @deffn {Scheme Procedure} uuid @var{str} [@var{type}]
  11326. Return an opaque UUID (unique identifier) object of the given @var{type}
  11327. (a symbol) by parsing @var{str} (a string):
  11328. @lisp
  11329. (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")
  11330. @result{} #<<uuid> type: dce bv: @dots{}>
  11331. (uuid "1234-ABCD" 'fat)
  11332. @result{} #<<uuid> type: fat bv: @dots{}>
  11333. @end lisp
  11334. @var{type} may be one of @code{dce}, @code{iso9660}, @code{fat},
  11335. @code{ntfs}, or one of the commonly found synonyms for these.
  11336. UUIDs are another way to unambiguously refer to file systems in
  11337. operating system configuration. See the examples above.
  11338. @end deffn
  11339. @node Btrfs file system
  11340. @subsection Btrfs file system
  11341. The Btrfs has special features, such as subvolumes, that merit being
  11342. explained in more details. The following section attempts to cover
  11343. basic as well as complex uses of a Btrfs file system with the Guix
  11344. System.
  11345. In its simplest usage, a Btrfs file system can be described, for
  11346. example, by:
  11347. @lisp
  11348. (file-system
  11349. (mount-point "/home")
  11350. (type "btrfs")
  11351. (device (file-system-label "my-home")))
  11352. @end lisp
  11353. The example below is more complex, as it makes use of a Btrfs
  11354. subvolume, named @code{rootfs}. The parent Btrfs file system is labeled
  11355. @code{my-btrfs-pool}, and is located on an encrypted device (hence the
  11356. dependency on @code{mapped-devices}):
  11357. @lisp
  11358. (file-system
  11359. (device (file-system-label "my-btrfs-pool"))
  11360. (mount-point "/")
  11361. (type "btrfs")
  11362. (options "subvol=rootfs")
  11363. (dependencies mapped-devices))
  11364. @end lisp
  11365. Some bootloaders, for example GRUB, only mount a Btrfs partition at its
  11366. top level during the early boot, and rely on their configuration to
  11367. refer to the correct subvolume path within that top level. The
  11368. bootloaders operating in this way typically produce their configuration
  11369. on a running system where the Btrfs partitions are already mounted and
  11370. where the subvolume information is readily available. As an example,
  11371. @command{grub-mkconfig}, the configuration generator command shipped
  11372. with GRUB, reads @file{/proc/self/mountinfo} to determine the top-level
  11373. path of a subvolume.
  11374. The Guix System produces a bootloader configuration using the operating
  11375. system configuration as its sole input; it is therefore necessary to
  11376. extract the subvolume name on which @file{/gnu/store} lives (if any)
  11377. from that operating system configuration. To better illustrate,
  11378. consider a subvolume named 'rootfs' which contains the root file system
  11379. data. In such situation, the GRUB bootloader would only see the top
  11380. level of the root Btrfs partition, e.g.:
  11381. @example
  11382. / (top level)
  11383. ├── rootfs (subvolume directory)
  11384. ├── gnu (normal directory)
  11385. ├── store (normal directory)
  11386. [...]
  11387. @end example
  11388. Thus, the subvolume name must be prepended to the @file{/gnu/store} path
  11389. of the kernel, initrd binaries and any other files referred to in the
  11390. GRUB configuration that must be found during the early boot.
  11391. The next example shows a nested hierarchy of subvolumes and
  11392. directories:
  11393. @example
  11394. / (top level)
  11395. ├── rootfs (subvolume)
  11396. ├── gnu (normal directory)
  11397. ├── store (subvolume)
  11398. [...]
  11399. @end example
  11400. This scenario would work without mounting the 'store' subvolume.
  11401. Mounting 'rootfs' is sufficient, since the subvolume name matches its
  11402. intended mount point in the file system hierarchy. Alternatively, the
  11403. 'store' subvolume could be referred to by setting the @code{subvol}
  11404. option to either @code{/rootfs/gnu/store} or @code{rootfs/gnu/store}.
  11405. Finally, a more contrived example of nested subvolumes:
  11406. @example
  11407. / (top level)
  11408. ├── root-snapshots (subvolume)
  11409. ├── root-current (subvolume)
  11410. ├── guix-store (subvolume)
  11411. [...]
  11412. @end example
  11413. Here, the 'guix-store' subvolume doesn't match its intended mount point,
  11414. so it is necessary to mount it. The subvolume must be fully specified,
  11415. by passing its file name to the @code{subvol} option. To illustrate,
  11416. the 'guix-store' subvolume could be mounted on @file{/gnu/store} by using
  11417. a file system declaration such as:
  11418. @lisp
  11419. (file-system
  11420. (device (file-system-label "btrfs-pool-1"))
  11421. (mount-point "/gnu/store")
  11422. (type "btrfs")
  11423. (options "subvol=root-snapshots/root-current/guix-store,\
  11424. compress-force=zstd,space_cache=v2"))
  11425. @end lisp
  11426. @node Mapped Devices
  11427. @section Mapped Devices
  11428. @cindex device mapping
  11429. @cindex mapped devices
  11430. The Linux kernel has a notion of @dfn{device mapping}: a block device,
  11431. such as a hard disk partition, can be @dfn{mapped} into another device,
  11432. usually in @code{/dev/mapper/},
  11433. with additional processing over the data that flows through
  11434. it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
  11435. concept of a ``mapped device'' and that of a file system: both boil down
  11436. to @emph{translating} input/output operations made on a file to
  11437. operations on its backing store. Thus, the Hurd implements mapped
  11438. devices, like file systems, using the generic @dfn{translator} mechanism
  11439. (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
  11440. typical example is encryption device mapping: all writes to the mapped
  11441. device are encrypted, and all reads are deciphered, transparently.
  11442. Guix extends this notion by considering any device or set of devices that
  11443. are @dfn{transformed} in some way to create a new device; for instance,
  11444. RAID devices are obtained by @dfn{assembling} several other devices, such
  11445. as hard disks or partitions, into a new one that behaves as one partition.
  11446. Mapped devices are declared using the @code{mapped-device} form,
  11447. defined as follows; for examples, see below.
  11448. @deftp {Data Type} mapped-device
  11449. Objects of this type represent device mappings that will be made when
  11450. the system boots up.
  11451. @table @code
  11452. @item source
  11453. This is either a string specifying the name of the block device to be mapped,
  11454. such as @code{"/dev/sda3"}, or a list of such strings when several devices
  11455. need to be assembled for creating a new one. In case of LVM this is a
  11456. string specifying name of the volume group to be mapped.
  11457. @item target
  11458. This string specifies the name of the resulting mapped device. For
  11459. kernel mappers such as encrypted devices of type @code{luks-device-mapping},
  11460. specifying @code{"my-partition"} leads to the creation of
  11461. the @code{"/dev/mapper/my-partition"} device.
  11462. For RAID devices of type @code{raid-device-mapping}, the full device name
  11463. such as @code{"/dev/md0"} needs to be given.
  11464. LVM logical volumes of type @code{lvm-device-mapping} need to
  11465. be specified as @code{"VGNAME-LVNAME"}.
  11466. @item targets
  11467. This list of strings specifies names of the resulting mapped devices in case
  11468. there are several. The format is identical to @var{target}.
  11469. @item type
  11470. This must be a @code{mapped-device-kind} object, which specifies how
  11471. @var{source} is mapped to @var{target}.
  11472. @end table
  11473. @end deftp
  11474. @defvr {Scheme Variable} luks-device-mapping
  11475. This defines LUKS block device encryption using the @command{cryptsetup}
  11476. command from the package with the same name. It relies on the
  11477. @code{dm-crypt} Linux kernel module.
  11478. @end defvr
  11479. @defvr {Scheme Variable} raid-device-mapping
  11480. This defines a RAID device, which is assembled using the @code{mdadm}
  11481. command from the package with the same name. It requires a Linux kernel
  11482. module for the appropriate RAID level to be loaded, such as @code{raid456}
  11483. for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
  11484. @end defvr
  11485. @cindex LVM, logical volume manager
  11486. @defvr {Scheme Variable} lvm-device-mapping
  11487. This defines one or more logical volumes for the Linux
  11488. @uref{https://www.sourceware.org/lvm2/, Logical Volume Manager (LVM)}.
  11489. The volume group is activated by the @command{vgchange} command from the
  11490. @code{lvm2} package.
  11491. @end defvr
  11492. @cindex disk encryption
  11493. @cindex LUKS
  11494. The following example specifies a mapping from @file{/dev/sda3} to
  11495. @file{/dev/mapper/home} using LUKS---the
  11496. @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
  11497. standard mechanism for disk encryption.
  11498. The @file{/dev/mapper/home}
  11499. device can then be used as the @code{device} of a @code{file-system}
  11500. declaration (@pxref{File Systems}).
  11501. @lisp
  11502. (mapped-device
  11503. (source "/dev/sda3")
  11504. (target "home")
  11505. (type luks-device-mapping))
  11506. @end lisp
  11507. Alternatively, to become independent of device numbering, one may obtain
  11508. the LUKS UUID (@dfn{unique identifier}) of the source device by a
  11509. command like:
  11510. @example
  11511. cryptsetup luksUUID /dev/sda3
  11512. @end example
  11513. and use it as follows:
  11514. @lisp
  11515. (mapped-device
  11516. (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
  11517. (target "home")
  11518. (type luks-device-mapping))
  11519. @end lisp
  11520. @cindex swap encryption
  11521. It is also desirable to encrypt swap space, since swap space may contain
  11522. sensitive data. One way to accomplish that is to use a swap file in a
  11523. file system on a device mapped via LUKS encryption. In this way, the
  11524. swap file is encrypted because the entire device is encrypted.
  11525. @xref{Preparing for Installation,,Disk Partitioning}, for an example.
  11526. A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
  11527. may be declared as follows:
  11528. @lisp
  11529. (mapped-device
  11530. (source (list "/dev/sda1" "/dev/sdb1"))
  11531. (target "/dev/md0")
  11532. (type raid-device-mapping))
  11533. @end lisp
  11534. The @file{/dev/md0} device can then be used as the @code{device} of a
  11535. @code{file-system} declaration (@pxref{File Systems}).
  11536. Note that the RAID level need not be given; it is chosen during the
  11537. initial creation and formatting of the RAID device and is determined
  11538. automatically later.
  11539. LVM logical volumes ``alpha'' and ``beta'' from volume group ``vg0'' can
  11540. be declared as follows:
  11541. @lisp
  11542. (mapped-device
  11543. (source "vg0")
  11544. (targets (list "vg0-alpha" "vg0-beta"))
  11545. (type lvm-device-mapping))
  11546. @end lisp
  11547. Devices @file{/dev/mapper/vg0-alpha} and @file{/dev/mapper/vg0-beta} can
  11548. then be used as the @code{device} of a @code{file-system} declaration
  11549. (@pxref{File Systems}).
  11550. @node User Accounts
  11551. @section User Accounts
  11552. @cindex users
  11553. @cindex accounts
  11554. @cindex user accounts
  11555. User accounts and groups are entirely managed through the
  11556. @code{operating-system} declaration. They are specified with the
  11557. @code{user-account} and @code{user-group} forms:
  11558. @lisp
  11559. (user-account
  11560. (name "alice")
  11561. (group "users")
  11562. (supplementary-groups '("wheel" ;allow use of sudo, etc.
  11563. "audio" ;sound card
  11564. "video" ;video devices such as webcams
  11565. "cdrom")) ;the good ol' CD-ROM
  11566. (comment "Bob's sister"))
  11567. @end lisp
  11568. Here's a user account that uses a different shell and a custom home
  11569. directory (the default would be @file{"/home/bob"}):
  11570. @lisp
  11571. (user-account
  11572. (name "bob")
  11573. (group "users")
  11574. (comment "Alice's bro")
  11575. (shell (file-append zsh "/bin/zsh"))
  11576. (home-directory "/home/robert"))
  11577. @end lisp
  11578. When booting or upon completion of @command{guix system reconfigure},
  11579. the system ensures that only the user accounts and groups specified in
  11580. the @code{operating-system} declaration exist, and with the specified
  11581. properties. Thus, account or group creations or modifications made by
  11582. directly invoking commands such as @command{useradd} are lost upon
  11583. reconfiguration or reboot. This ensures that the system remains exactly
  11584. as declared.
  11585. @deftp {Data Type} user-account
  11586. Objects of this type represent user accounts. The following members may
  11587. be specified:
  11588. @table @asis
  11589. @item @code{name}
  11590. The name of the user account.
  11591. @item @code{group}
  11592. @cindex groups
  11593. This is the name (a string) or identifier (a number) of the user group
  11594. this account belongs to.
  11595. @item @code{supplementary-groups} (default: @code{'()})
  11596. Optionally, this can be defined as a list of group names that this
  11597. account belongs to.
  11598. @item @code{uid} (default: @code{#f})
  11599. This is the user ID for this account (a number), or @code{#f}. In the
  11600. latter case, a number is automatically chosen by the system when the
  11601. account is created.
  11602. @item @code{comment} (default: @code{""})
  11603. A comment about the account, such as the account owner's full name.
  11604. @item @code{home-directory}
  11605. This is the name of the home directory for the account.
  11606. @item @code{create-home-directory?} (default: @code{#t})
  11607. Indicates whether the home directory of this account should be created
  11608. if it does not exist yet.
  11609. @item @code{shell} (default: Bash)
  11610. This is a G-expression denoting the file name of a program to be used as
  11611. the shell (@pxref{G-Expressions}). For example, you would refer to the
  11612. Bash executable like this:
  11613. @lisp
  11614. (file-append bash "/bin/bash")
  11615. @end lisp
  11616. @noindent
  11617. ... and to the Zsh executable like that:
  11618. @lisp
  11619. (file-append zsh "/bin/zsh")
  11620. @end lisp
  11621. @item @code{system?} (default: @code{#f})
  11622. This Boolean value indicates whether the account is a ``system''
  11623. account. System accounts are sometimes treated specially; for instance,
  11624. graphical login managers do not list them.
  11625. @anchor{user-account-password}
  11626. @cindex password, for user accounts
  11627. @item @code{password} (default: @code{#f})
  11628. You would normally leave this field to @code{#f}, initialize user
  11629. passwords as @code{root} with the @command{passwd} command, and then let
  11630. users change it with @command{passwd}. Passwords set with
  11631. @command{passwd} are of course preserved across reboot and
  11632. reconfiguration.
  11633. If you @emph{do} want to set an initial password for an account, then
  11634. this field must contain the encrypted password, as a string. You can use the
  11635. @code{crypt} procedure for this purpose:
  11636. @lisp
  11637. (user-account
  11638. (name "charlie")
  11639. (group "users")
  11640. ;; Specify a SHA-512-hashed initial password.
  11641. (password (crypt "InitialPassword!" "$6$abc")))
  11642. @end lisp
  11643. @quotation Note
  11644. The hash of this initial password will be available in a file in
  11645. @file{/gnu/store}, readable by all the users, so this method must be used with
  11646. care.
  11647. @end quotation
  11648. @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
  11649. more information on password encryption, and @ref{Encryption,,, guile, GNU
  11650. Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
  11651. @end table
  11652. @end deftp
  11653. @cindex groups
  11654. User group declarations are even simpler:
  11655. @lisp
  11656. (user-group (name "students"))
  11657. @end lisp
  11658. @deftp {Data Type} user-group
  11659. This type is for, well, user groups. There are just a few fields:
  11660. @table @asis
  11661. @item @code{name}
  11662. The name of the group.
  11663. @item @code{id} (default: @code{#f})
  11664. The group identifier (a number). If @code{#f}, a new number is
  11665. automatically allocated when the group is created.
  11666. @item @code{system?} (default: @code{#f})
  11667. This Boolean value indicates whether the group is a ``system'' group.
  11668. System groups have low numerical IDs.
  11669. @item @code{password} (default: @code{#f})
  11670. What, user groups can have a password? Well, apparently yes. Unless
  11671. @code{#f}, this field specifies the password of the group.
  11672. @end table
  11673. @end deftp
  11674. For convenience, a variable lists all the basic user groups one may
  11675. expect:
  11676. @defvr {Scheme Variable} %base-groups
  11677. This is the list of basic user groups that users and/or packages expect
  11678. to be present on the system. This includes groups such as ``root'',
  11679. ``wheel'', and ``users'', as well as groups used to control access to
  11680. specific devices such as ``audio'', ``disk'', and ``cdrom''.
  11681. @end defvr
  11682. @defvr {Scheme Variable} %base-user-accounts
  11683. This is the list of basic system accounts that programs may expect to
  11684. find on a GNU/Linux system, such as the ``nobody'' account.
  11685. Note that the ``root'' account is not included here. It is a
  11686. special-case and is automatically added whether or not it is specified.
  11687. @end defvr
  11688. @node Keyboard Layout
  11689. @section Keyboard Layout
  11690. @cindex keyboard layout
  11691. @cindex keymap
  11692. To specify what each key of your keyboard does, you need to tell the operating
  11693. system what @dfn{keyboard layout} you want to use. The default, when nothing
  11694. is specified, is the US English QWERTY layout for 105-key PC keyboards.
  11695. However, German speakers will usually prefer the German QWERTZ layout, French
  11696. speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
  11697. or bépo, and they might even want to further customize the effect of some of
  11698. the keys. This section explains how to get that done.
  11699. @cindex keyboard layout, definition
  11700. There are three components that will want to know about your keyboard layout:
  11701. @itemize
  11702. @item
  11703. The @emph{bootloader} may want to know what keyboard layout you want to use
  11704. (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
  11705. you want, for instance, to make sure that you can type the passphrase of your
  11706. encrypted root partition using the right layout.
  11707. @item
  11708. The @emph{operating system kernel}, Linux, will need that so that the console
  11709. is properly configured (@pxref{operating-system Reference,
  11710. @code{keyboard-layout}}).
  11711. @item
  11712. The @emph{graphical display server}, usually Xorg, also has its own idea of
  11713. the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
  11714. @end itemize
  11715. Guix allows you to configure all three separately but, fortunately, it allows
  11716. you to share the same keyboard layout for all three components.
  11717. @cindex XKB, keyboard layouts
  11718. Keyboard layouts are represented by records created by the
  11719. @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
  11720. the X Keyboard extension (XKB), each layout has four attributes: a name (often
  11721. a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
  11722. optional variant name, an optional keyboard model name, and a possibly empty
  11723. list of additional options. In most cases the layout name is all you care
  11724. about.
  11725. @deffn {Scheme Procedure} keyboard-layout @var{name} [@var{variant}] @
  11726. [#:model] [#:options '()]
  11727. Return a new keyboard layout with the given @var{name} and @var{variant}.
  11728. @var{name} must be a string such as @code{"fr"}; @var{variant} must be a
  11729. string such as @code{"bepo"} or @code{"nodeadkeys"}. See the
  11730. @code{xkeyboard-config} package for valid options.
  11731. @end deffn
  11732. Here are a few examples:
  11733. @lisp
  11734. ;; The German QWERTZ layout. Here we assume a standard
  11735. ;; "pc105" keyboard model.
  11736. (keyboard-layout "de")
  11737. ;; The bépo variant of the French layout.
  11738. (keyboard-layout "fr" "bepo")
  11739. ;; The Catalan layout.
  11740. (keyboard-layout "es" "cat")
  11741. ;; Arabic layout with "Alt-Shift" to switch to US layout.
  11742. (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
  11743. ;; The Latin American Spanish layout. In addition, the
  11744. ;; "Caps Lock" key is used as an additional "Ctrl" key,
  11745. ;; and the "Menu" key is used as a "Compose" key to enter
  11746. ;; accented letters.
  11747. (keyboard-layout "latam"
  11748. #:options '("ctrl:nocaps" "compose:menu"))
  11749. ;; The Russian layout for a ThinkPad keyboard.
  11750. (keyboard-layout "ru" #:model "thinkpad")
  11751. ;; The "US international" layout, which is the US layout plus
  11752. ;; dead keys to enter accented characters. This is for an
  11753. ;; Apple MacBook keyboard.
  11754. (keyboard-layout "us" "intl" #:model "macbook78")
  11755. @end lisp
  11756. See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
  11757. for a complete list of supported layouts, variants, and models.
  11758. @cindex keyboard layout, configuration
  11759. Let's say you want your system to use the Turkish keyboard layout throughout
  11760. your system---bootloader, console, and Xorg. Here's what your system
  11761. configuration would look like:
  11762. @findex set-xorg-configuration
  11763. @lisp
  11764. ;; Using the Turkish layout for the bootloader, the console,
  11765. ;; and for Xorg.
  11766. (operating-system
  11767. ;; ...
  11768. (keyboard-layout (keyboard-layout "tr")) ;for the console
  11769. (bootloader (bootloader-configuration
  11770. (bootloader grub-efi-bootloader)
  11771. (target "/boot/efi")
  11772. (keyboard-layout keyboard-layout))) ;for GRUB
  11773. (services (cons (set-xorg-configuration
  11774. (xorg-configuration ;for Xorg
  11775. (keyboard-layout keyboard-layout)))
  11776. %desktop-services)))
  11777. @end lisp
  11778. In the example above, for GRUB and for Xorg, we just refer to the
  11779. @code{keyboard-layout} field defined above, but we could just as well refer to
  11780. a different layout. The @code{set-xorg-configuration} procedure communicates
  11781. the desired Xorg configuration to the graphical log-in manager, by default
  11782. GDM.
  11783. We've discussed how to specify the @emph{default} keyboard layout of your
  11784. system when it starts, but you can also adjust it at run time:
  11785. @itemize
  11786. @item
  11787. If you're using GNOME, its settings panel has a ``Region & Language'' entry
  11788. where you can select one or more keyboard layouts.
  11789. @item
  11790. Under Xorg, the @command{setxkbmap} command (from the same-named package)
  11791. allows you to change the current layout. For example, this is how you would
  11792. change the layout to US Dvorak:
  11793. @example
  11794. setxkbmap us dvorak
  11795. @end example
  11796. @item
  11797. The @code{loadkeys} command changes the keyboard layout in effect in the Linux
  11798. console. However, note that @code{loadkeys} does @emph{not} use the XKB
  11799. keyboard layout categorization described above. The command below loads the
  11800. French bépo layout:
  11801. @example
  11802. loadkeys fr-bepo
  11803. @end example
  11804. @end itemize
  11805. @node Locales
  11806. @section Locales
  11807. @cindex locale
  11808. A @dfn{locale} defines cultural conventions for a particular language
  11809. and region of the world (@pxref{Locales,,, libc, The GNU C Library
  11810. Reference Manual}). Each locale has a name that typically has the form
  11811. @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
  11812. @code{fr_LU.utf8} designates the locale for the French language, with
  11813. cultural conventions from Luxembourg, and using the UTF-8 encoding.
  11814. @cindex locale definition
  11815. Usually, you will want to specify the default locale for the machine
  11816. using the @code{locale} field of the @code{operating-system} declaration
  11817. (@pxref{operating-system Reference, @code{locale}}).
  11818. The selected locale is automatically added to the @dfn{locale
  11819. definitions} known to the system if needed, with its codeset inferred
  11820. from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
  11821. @code{UTF-8} codeset. Additional locale definitions can be specified in
  11822. the @code{locale-definitions} slot of @code{operating-system}---this is
  11823. useful, for instance, if the codeset could not be inferred from the
  11824. locale name. The default set of locale definitions includes some widely
  11825. used locales, but not all the available locales, in order to save space.
  11826. For instance, to add the North Frisian locale for Germany, the value of
  11827. that field may be:
  11828. @lisp
  11829. (cons (locale-definition
  11830. (name "fy_DE.utf8") (source "fy_DE"))
  11831. %default-locale-definitions)
  11832. @end lisp
  11833. Likewise, to save space, one might want @code{locale-definitions} to
  11834. list only the locales that are actually used, as in:
  11835. @lisp
  11836. (list (locale-definition
  11837. (name "ja_JP.eucjp") (source "ja_JP")
  11838. (charset "EUC-JP")))
  11839. @end lisp
  11840. @vindex LOCPATH
  11841. The compiled locale definitions are available at
  11842. @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
  11843. version, which is the default location where the GNU@tie{}libc provided
  11844. by Guix looks for locale data. This can be overridden using the
  11845. @env{LOCPATH} environment variable (@pxref{locales-and-locpath,
  11846. @env{LOCPATH} and locale packages}).
  11847. The @code{locale-definition} form is provided by the @code{(gnu system
  11848. locale)} module. Details are given below.
  11849. @deftp {Data Type} locale-definition
  11850. This is the data type of a locale definition.
  11851. @table @asis
  11852. @item @code{name}
  11853. The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
  11854. Reference Manual}, for more information on locale names.
  11855. @item @code{source}
  11856. The name of the source for that locale. This is typically the
  11857. @code{@var{language}_@var{territory}} part of the locale name.
  11858. @item @code{charset} (default: @code{"UTF-8"})
  11859. The ``character set'' or ``code set'' for that locale,
  11860. @uref{https://www.iana.org/assignments/character-sets, as defined by
  11861. IANA}.
  11862. @end table
  11863. @end deftp
  11864. @defvr {Scheme Variable} %default-locale-definitions
  11865. A list of commonly used UTF-8 locales, used as the default
  11866. value of the @code{locale-definitions} field of @code{operating-system}
  11867. declarations.
  11868. @cindex locale name
  11869. @cindex normalized codeset in locale names
  11870. These locale definitions use the @dfn{normalized codeset} for the part
  11871. that follows the dot in the name (@pxref{Using gettextized software,
  11872. normalized codeset,, libc, The GNU C Library Reference Manual}). So for
  11873. instance it has @code{uk_UA.utf8} but @emph{not}, say,
  11874. @code{uk_UA.UTF-8}.
  11875. @end defvr
  11876. @subsection Locale Data Compatibility Considerations
  11877. @cindex incompatibility, of locale data
  11878. @code{operating-system} declarations provide a @code{locale-libcs} field
  11879. to specify the GNU@tie{}libc packages that are used to compile locale
  11880. declarations (@pxref{operating-system Reference}). ``Why would I
  11881. care?'', you may ask. Well, it turns out that the binary format of
  11882. locale data is occasionally incompatible from one libc version to
  11883. another.
  11884. @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
  11885. @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
  11886. For instance, a program linked against libc version 2.21 is unable to
  11887. read locale data produced with libc 2.22; worse, that program
  11888. @emph{aborts} instead of simply ignoring the incompatible locale
  11889. data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
  11890. the incompatible locale data, which is already an improvement.}.
  11891. Similarly, a program linked against libc 2.22 can read most, but not
  11892. all, of the locale data from libc 2.21 (specifically, @env{LC_COLLATE}
  11893. data is incompatible); thus calls to @code{setlocale} may fail, but
  11894. programs will not abort.
  11895. The ``problem'' with Guix is that users have a lot of freedom: They can
  11896. choose whether and when to upgrade software in their profiles, and might
  11897. be using a libc version different from the one the system administrator
  11898. used to build the system-wide locale data.
  11899. Fortunately, unprivileged users can also install their own locale data
  11900. and define @env{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
  11901. @env{GUIX_LOCPATH} and locale packages}).
  11902. Still, it is best if the system-wide locale data at
  11903. @file{/run/current-system/locale} is built for all the libc versions
  11904. actually in use on the system, so that all the programs can access
  11905. it---this is especially crucial on a multi-user system. To do that, the
  11906. administrator can specify several libc packages in the
  11907. @code{locale-libcs} field of @code{operating-system}:
  11908. @lisp
  11909. (use-package-modules base)
  11910. (operating-system
  11911. ;; @dots{}
  11912. (locale-libcs (list glibc-2.21 (canonical-package glibc))))
  11913. @end lisp
  11914. This example would lead to a system containing locale definitions for
  11915. both libc 2.21 and the current version of libc in
  11916. @file{/run/current-system/locale}.
  11917. @node Services
  11918. @section Services
  11919. @cindex system services
  11920. An important part of preparing an @code{operating-system} declaration is
  11921. listing @dfn{system services} and their configuration (@pxref{Using the
  11922. Configuration System}). System services are typically daemons launched
  11923. when the system boots, or other actions needed at that time---e.g.,
  11924. configuring network access.
  11925. Guix has a broad definition of ``service'' (@pxref{Service
  11926. Composition}), but many services are managed by the GNU@tie{}Shepherd
  11927. (@pxref{Shepherd Services}). On a running system, the @command{herd}
  11928. command allows you to list the available services, show their status,
  11929. start and stop them, or do other specific operations (@pxref{Jump
  11930. Start,,, shepherd, The GNU Shepherd Manual}). For example:
  11931. @example
  11932. # herd status
  11933. @end example
  11934. The above command, run as @code{root}, lists the currently defined
  11935. services. The @command{herd doc} command shows a synopsis of the given
  11936. service and its associated actions:
  11937. @example
  11938. # herd doc nscd
  11939. Run libc's name service cache daemon (nscd).
  11940. # herd doc nscd action invalidate
  11941. invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
  11942. @end example
  11943. The @command{start}, @command{stop}, and @command{restart} sub-commands
  11944. have the effect you would expect. For instance, the commands below stop
  11945. the nscd service and restart the Xorg display server:
  11946. @example
  11947. # herd stop nscd
  11948. Service nscd has been stopped.
  11949. # herd restart xorg-server
  11950. Service xorg-server has been stopped.
  11951. Service xorg-server has been started.
  11952. @end example
  11953. The following sections document the available services, starting with
  11954. the core services, that may be used in an @code{operating-system}
  11955. declaration.
  11956. @menu
  11957. * Base Services:: Essential system services.
  11958. * Scheduled Job Execution:: The mcron service.
  11959. * Log Rotation:: The rottlog service.
  11960. * Networking Services:: Network setup, SSH daemon, etc.
  11961. * Unattended Upgrades:: Automated system upgrades.
  11962. * X Window:: Graphical display.
  11963. * Printing Services:: Local and remote printer support.
  11964. * Desktop Services:: D-Bus and desktop services.
  11965. * Sound Services:: ALSA and Pulseaudio services.
  11966. * Database Services:: SQL databases, key-value stores, etc.
  11967. * Mail Services:: IMAP, POP3, SMTP, and all that.
  11968. * Messaging Services:: Messaging services.
  11969. * Telephony Services:: Telephony services.
  11970. * File-Sharing Services:: File-sharing services.
  11971. * Monitoring Services:: Monitoring services.
  11972. * Kerberos Services:: Kerberos services.
  11973. * LDAP Services:: LDAP services.
  11974. * Web Services:: Web servers.
  11975. * Certificate Services:: TLS certificates via Let's Encrypt.
  11976. * DNS Services:: DNS daemons.
  11977. * VPN Services:: VPN daemons.
  11978. * Network File System:: NFS related services.
  11979. * Continuous Integration:: The Cuirass service.
  11980. * Power Management Services:: Extending battery life.
  11981. * Audio Services:: The MPD.
  11982. * Virtualization Services:: Virtualization services.
  11983. * Version Control Services:: Providing remote access to Git repositories.
  11984. * Game Services:: Game servers.
  11985. * PAM Mount Service:: Service to mount volumes when logging in.
  11986. * Guix Services:: Services relating specifically to Guix.
  11987. * Linux Services:: Services tied to the Linux kernel.
  11988. * Hurd Services:: Services specific for a Hurd System.
  11989. * Miscellaneous Services:: Other services.
  11990. @end menu
  11991. @node Base Services
  11992. @subsection Base Services
  11993. The @code{(gnu services base)} module provides definitions for the basic
  11994. services that one expects from the system. The services exported by
  11995. this module are listed below.
  11996. @defvr {Scheme Variable} %base-services
  11997. This variable contains a list of basic services (@pxref{Service Types
  11998. and Services}, for more information on service objects) one would
  11999. expect from the system: a login service (mingetty) on each tty, syslogd,
  12000. the libc name service cache daemon (nscd), the udev device manager, and
  12001. more.
  12002. This is the default value of the @code{services} field of
  12003. @code{operating-system} declarations. Usually, when customizing a
  12004. system, you will want to append services to @code{%base-services}, like
  12005. this:
  12006. @lisp
  12007. (append (list (service avahi-service-type)
  12008. (service openssh-service-type))
  12009. %base-services)
  12010. @end lisp
  12011. @end defvr
  12012. @defvr {Scheme Variable} special-files-service-type
  12013. This is the service that sets up ``special files'' such as
  12014. @file{/bin/sh}; an instance of it is part of @code{%base-services}.
  12015. The value associated with @code{special-files-service-type} services
  12016. must be a list of tuples where the first element is the ``special file''
  12017. and the second element is its target. By default it is:
  12018. @cindex @file{/bin/sh}
  12019. @cindex @file{sh}, in @file{/bin}
  12020. @lisp
  12021. `(("/bin/sh" ,(file-append bash "/bin/sh")))
  12022. @end lisp
  12023. @cindex @file{/usr/bin/env}
  12024. @cindex @file{env}, in @file{/usr/bin}
  12025. If you want to add, say, @code{/usr/bin/env} to your system, you can
  12026. change it to:
  12027. @lisp
  12028. `(("/bin/sh" ,(file-append bash "/bin/sh"))
  12029. ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
  12030. @end lisp
  12031. Since this is part of @code{%base-services}, you can use
  12032. @code{modify-services} to customize the set of special files
  12033. (@pxref{Service Reference, @code{modify-services}}). But the simple way
  12034. to add a special file is @i{via} the @code{extra-special-file} procedure
  12035. (see below).
  12036. @end defvr
  12037. @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
  12038. Use @var{target} as the ``special file'' @var{file}.
  12039. For example, adding the following lines to the @code{services} field of
  12040. your operating system declaration leads to a @file{/usr/bin/env}
  12041. symlink:
  12042. @lisp
  12043. (extra-special-file "/usr/bin/env"
  12044. (file-append coreutils "/bin/env"))
  12045. @end lisp
  12046. @end deffn
  12047. @deffn {Scheme Procedure} host-name-service @var{name}
  12048. Return a service that sets the host name to @var{name}.
  12049. @end deffn
  12050. @defvr {Scheme Variable} console-font-service-type
  12051. Install the given fonts on the specified ttys (fonts are per
  12052. virtual console on the kernel Linux). The value of this service is a list of
  12053. tty/font pairs. The font can be the name of a font provided by the @code{kbd}
  12054. package or any valid argument to @command{setfont}, as in this example:
  12055. @lisp
  12056. `(("tty1" . "LatGrkCyr-8x16")
  12057. ("tty2" . ,(file-append
  12058. font-tamzen
  12059. "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
  12060. ("tty3" . ,(file-append
  12061. font-terminus
  12062. "/share/consolefonts/ter-132n"))) ; for HDPI
  12063. @end lisp
  12064. @end defvr
  12065. @deffn {Scheme Procedure} login-service @var{config}
  12066. Return a service to run login according to @var{config}, a
  12067. @code{<login-configuration>} object, which specifies the message of the day,
  12068. among other things.
  12069. @end deffn
  12070. @deftp {Data Type} login-configuration
  12071. This is the data type representing the configuration of login.
  12072. @table @asis
  12073. @item @code{motd}
  12074. @cindex message of the day
  12075. A file-like object containing the ``message of the day''.
  12076. @item @code{allow-empty-passwords?} (default: @code{#t})
  12077. Allow empty passwords by default so that first-time users can log in when
  12078. the 'root' account has just been created.
  12079. @end table
  12080. @end deftp
  12081. @deffn {Scheme Procedure} mingetty-service @var{config}
  12082. Return a service to run mingetty according to @var{config}, a
  12083. @code{<mingetty-configuration>} object, which specifies the tty to run, among
  12084. other things.
  12085. @end deffn
  12086. @deftp {Data Type} mingetty-configuration
  12087. This is the data type representing the configuration of Mingetty, which
  12088. provides the default implementation of virtual console log-in.
  12089. @table @asis
  12090. @item @code{tty}
  12091. The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
  12092. @item @code{auto-login} (default: @code{#f})
  12093. When true, this field must be a string denoting the user name under
  12094. which the system automatically logs in. When it is @code{#f}, a
  12095. user name and password must be entered to log in.
  12096. @item @code{login-program} (default: @code{#f})
  12097. This must be either @code{#f}, in which case the default log-in program
  12098. is used (@command{login} from the Shadow tool suite), or a gexp denoting
  12099. the name of the log-in program.
  12100. @item @code{login-pause?} (default: @code{#f})
  12101. When set to @code{#t} in conjunction with @var{auto-login}, the user
  12102. will have to press a key before the log-in shell is launched.
  12103. @item @code{clear-on-logout?} (default: @code{#t})
  12104. When set to @code{#t}, the screen will be cleared after logout.
  12105. @item @code{mingetty} (default: @var{mingetty})
  12106. The Mingetty package to use.
  12107. @end table
  12108. @end deftp
  12109. @deffn {Scheme Procedure} agetty-service @var{config}
  12110. Return a service to run agetty according to @var{config}, an
  12111. @code{<agetty-configuration>} object, which specifies the tty to run,
  12112. among other things.
  12113. @end deffn
  12114. @deftp {Data Type} agetty-configuration
  12115. This is the data type representing the configuration of agetty, which
  12116. implements virtual and serial console log-in. See the @code{agetty(8)}
  12117. man page for more information.
  12118. @table @asis
  12119. @item @code{tty}
  12120. The name of the console this agetty runs on, as a string---e.g.,
  12121. @code{"ttyS0"}. This argument is optional, it will default to
  12122. a reasonable default serial port used by the kernel Linux.
  12123. For this, if there is a value for an option @code{agetty.tty} in the kernel
  12124. command line, agetty will extract the device name of the serial port
  12125. from it and use that.
  12126. If not and if there is a value for an option @code{console} with a tty in
  12127. the Linux command line, agetty will extract the device name of the
  12128. serial port from it and use that.
  12129. In both cases, agetty will leave the other serial device settings
  12130. (baud rate etc.)@: alone---in the hope that Linux pinned them to the
  12131. correct values.
  12132. @item @code{baud-rate} (default: @code{#f})
  12133. A string containing a comma-separated list of one or more baud rates, in
  12134. descending order.
  12135. @item @code{term} (default: @code{#f})
  12136. A string containing the value used for the @env{TERM} environment
  12137. variable.
  12138. @item @code{eight-bits?} (default: @code{#f})
  12139. When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
  12140. disabled.
  12141. @item @code{auto-login} (default: @code{#f})
  12142. When passed a login name, as a string, the specified user will be logged
  12143. in automatically without prompting for their login name or password.
  12144. @item @code{no-reset?} (default: @code{#f})
  12145. When @code{#t}, don't reset terminal cflags (control modes).
  12146. @item @code{host} (default: @code{#f})
  12147. This accepts a string containing the ``login_host'', which will be written
  12148. into the @file{/var/run/utmpx} file.
  12149. @item @code{remote?} (default: @code{#f})
  12150. When set to @code{#t} in conjunction with @var{host}, this will add an
  12151. @code{-r} fakehost option to the command line of the login program
  12152. specified in @var{login-program}.
  12153. @item @code{flow-control?} (default: @code{#f})
  12154. When set to @code{#t}, enable hardware (RTS/CTS) flow control.
  12155. @item @code{no-issue?} (default: @code{#f})
  12156. When set to @code{#t}, the contents of the @file{/etc/issue} file will
  12157. not be displayed before presenting the login prompt.
  12158. @item @code{init-string} (default: @code{#f})
  12159. This accepts a string that will be sent to the tty or modem before
  12160. sending anything else. It can be used to initialize a modem.
  12161. @item @code{no-clear?} (default: @code{#f})
  12162. When set to @code{#t}, agetty will not clear the screen before showing
  12163. the login prompt.
  12164. @item @code{login-program} (default: (file-append shadow "/bin/login"))
  12165. This must be either a gexp denoting the name of a log-in program, or
  12166. unset, in which case the default value is the @command{login} from the
  12167. Shadow tool suite.
  12168. @item @code{local-line} (default: @code{#f})
  12169. Control the CLOCAL line flag. This accepts one of three symbols as
  12170. arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
  12171. the default value chosen by agetty is @code{'auto}.
  12172. @item @code{extract-baud?} (default: @code{#f})
  12173. When set to @code{#t}, instruct agetty to try to extract the baud rate
  12174. from the status messages produced by certain types of modems.
  12175. @item @code{skip-login?} (default: @code{#f})
  12176. When set to @code{#t}, do not prompt the user for a login name. This
  12177. can be used with @var{login-program} field to use non-standard login
  12178. systems.
  12179. @item @code{no-newline?} (default: @code{#f})
  12180. When set to @code{#t}, do not print a newline before printing the
  12181. @file{/etc/issue} file.
  12182. @c Is this dangerous only when used with login-program, or always?
  12183. @item @code{login-options} (default: @code{#f})
  12184. This option accepts a string containing options that are passed to the
  12185. login program. When used with the @var{login-program}, be aware that a
  12186. malicious user could try to enter a login name containing embedded
  12187. options that could be parsed by the login program.
  12188. @item @code{login-pause} (default: @code{#f})
  12189. When set to @code{#t}, wait for any key before showing the login prompt.
  12190. This can be used in conjunction with @var{auto-login} to save memory by
  12191. lazily spawning shells.
  12192. @item @code{chroot} (default: @code{#f})
  12193. Change root to the specified directory. This option accepts a directory
  12194. path as a string.
  12195. @item @code{hangup?} (default: @code{#f})
  12196. Use the Linux system call @code{vhangup} to do a virtual hangup of the
  12197. specified terminal.
  12198. @item @code{keep-baud?} (default: @code{#f})
  12199. When set to @code{#t}, try to keep the existing baud rate. The baud
  12200. rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
  12201. character.
  12202. @item @code{timeout} (default: @code{#f})
  12203. When set to an integer value, terminate if no user name could be read
  12204. within @var{timeout} seconds.
  12205. @item @code{detect-case?} (default: @code{#f})
  12206. When set to @code{#t}, turn on support for detecting an uppercase-only
  12207. terminal. This setting will detect a login name containing only
  12208. uppercase letters as indicating an uppercase-only terminal and turn on
  12209. some upper-to-lower case conversions. Note that this will not support
  12210. Unicode characters.
  12211. @item @code{wait-cr?} (default: @code{#f})
  12212. When set to @code{#t}, wait for the user or modem to send a
  12213. carriage-return or linefeed character before displaying
  12214. @file{/etc/issue} or login prompt. This is typically used with the
  12215. @var{init-string} option.
  12216. @item @code{no-hints?} (default: @code{#f})
  12217. When set to @code{#t}, do not print hints about Num, Caps, and Scroll
  12218. locks.
  12219. @item @code{no-hostname?} (default: @code{#f})
  12220. By default, the hostname is printed. When this option is set to
  12221. @code{#t}, no hostname will be shown at all.
  12222. @item @code{long-hostname?} (default: @code{#f})
  12223. By default, the hostname is only printed until the first dot. When this
  12224. option is set to @code{#t}, the fully qualified hostname by
  12225. @code{gethostname} or @code{getaddrinfo} is shown.
  12226. @item @code{erase-characters} (default: @code{#f})
  12227. This option accepts a string of additional characters that should be
  12228. interpreted as backspace when the user types their login name.
  12229. @item @code{kill-characters} (default: @code{#f})
  12230. This option accepts a string that should be interpreted to mean ``ignore
  12231. all previous characters'' (also called a ``kill'' character) when the user
  12232. types their login name.
  12233. @item @code{chdir} (default: @code{#f})
  12234. This option accepts, as a string, a directory path that will be changed
  12235. to before login.
  12236. @item @code{delay} (default: @code{#f})
  12237. This options accepts, as an integer, the number of seconds to sleep
  12238. before opening the tty and displaying the login prompt.
  12239. @item @code{nice} (default: @code{#f})
  12240. This option accepts, as an integer, the nice value with which to run the
  12241. @command{login} program.
  12242. @item @code{extra-options} (default: @code{'()})
  12243. This option provides an ``escape hatch'' for the user to provide arbitrary
  12244. command-line arguments to @command{agetty} as a list of strings.
  12245. @end table
  12246. @end deftp
  12247. @deffn {Scheme Procedure} kmscon-service-type @var{config}
  12248. Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
  12249. according to @var{config}, a @code{<kmscon-configuration>} object, which
  12250. specifies the tty to run, among other things.
  12251. @end deffn
  12252. @deftp {Data Type} kmscon-configuration
  12253. This is the data type representing the configuration of Kmscon, which
  12254. implements virtual console log-in.
  12255. @table @asis
  12256. @item @code{virtual-terminal}
  12257. The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
  12258. @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
  12259. A gexp denoting the name of the log-in program. The default log-in program is
  12260. @command{login} from the Shadow tool suite.
  12261. @item @code{login-arguments} (default: @code{'("-p")})
  12262. A list of arguments to pass to @command{login}.
  12263. @item @code{auto-login} (default: @code{#f})
  12264. When passed a login name, as a string, the specified user will be logged
  12265. in automatically without prompting for their login name or password.
  12266. @item @code{hardware-acceleration?} (default: #f)
  12267. Whether to use hardware acceleration.
  12268. @item @code{kmscon} (default: @var{kmscon})
  12269. The Kmscon package to use.
  12270. @end table
  12271. @end deftp
  12272. @cindex name service cache daemon
  12273. @cindex nscd
  12274. @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
  12275. [#:name-services '()]
  12276. Return a service that runs the libc name service cache daemon (nscd) with the
  12277. given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
  12278. Service Switch}, for an example.
  12279. For convenience, the Shepherd service for nscd provides the following actions:
  12280. @table @code
  12281. @item invalidate
  12282. @cindex cache invalidation, nscd
  12283. @cindex nscd, cache invalidation
  12284. This invalidate the given cache. For instance, running:
  12285. @example
  12286. herd invalidate nscd hosts
  12287. @end example
  12288. @noindent
  12289. invalidates the host name lookup cache of nscd.
  12290. @item statistics
  12291. Running @command{herd statistics nscd} displays information about nscd usage
  12292. and caches.
  12293. @end table
  12294. @end deffn
  12295. @defvr {Scheme Variable} %nscd-default-configuration
  12296. This is the default @code{<nscd-configuration>} value (see below) used
  12297. by @code{nscd-service}. It uses the caches defined by
  12298. @code{%nscd-default-caches}; see below.
  12299. @end defvr
  12300. @deftp {Data Type} nscd-configuration
  12301. This is the data type representing the name service cache daemon (nscd)
  12302. configuration.
  12303. @table @asis
  12304. @item @code{name-services} (default: @code{'()})
  12305. List of packages denoting @dfn{name services} that must be visible to
  12306. the nscd---e.g., @code{(list @var{nss-mdns})}.
  12307. @item @code{glibc} (default: @var{glibc})
  12308. Package object denoting the GNU C Library providing the @command{nscd}
  12309. command.
  12310. @item @code{log-file} (default: @code{"/var/log/nscd.log"})
  12311. Name of the nscd log file. This is where debugging output goes when
  12312. @code{debug-level} is strictly positive.
  12313. @item @code{debug-level} (default: @code{0})
  12314. Integer denoting the debugging levels. Higher numbers mean that more
  12315. debugging output is logged.
  12316. @item @code{caches} (default: @code{%nscd-default-caches})
  12317. List of @code{<nscd-cache>} objects denoting things to be cached; see
  12318. below.
  12319. @end table
  12320. @end deftp
  12321. @deftp {Data Type} nscd-cache
  12322. Data type representing a cache database of nscd and its parameters.
  12323. @table @asis
  12324. @item @code{database}
  12325. This is a symbol representing the name of the database to be cached.
  12326. Valid values are @code{passwd}, @code{group}, @code{hosts}, and
  12327. @code{services}, which designate the corresponding NSS database
  12328. (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
  12329. @item @code{positive-time-to-live}
  12330. @itemx @code{negative-time-to-live} (default: @code{20})
  12331. A number representing the number of seconds during which a positive or
  12332. negative lookup result remains in cache.
  12333. @item @code{check-files?} (default: @code{#t})
  12334. Whether to check for updates of the files corresponding to
  12335. @var{database}.
  12336. For instance, when @var{database} is @code{hosts}, setting this flag
  12337. instructs nscd to check for updates in @file{/etc/hosts} and to take
  12338. them into account.
  12339. @item @code{persistent?} (default: @code{#t})
  12340. Whether the cache should be stored persistently on disk.
  12341. @item @code{shared?} (default: @code{#t})
  12342. Whether the cache should be shared among users.
  12343. @item @code{max-database-size} (default: 32@tie{}MiB)
  12344. Maximum size in bytes of the database cache.
  12345. @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
  12346. @c settings, so leave them out.
  12347. @end table
  12348. @end deftp
  12349. @defvr {Scheme Variable} %nscd-default-caches
  12350. List of @code{<nscd-cache>} objects used by default by
  12351. @code{nscd-configuration} (see above).
  12352. It enables persistent and aggressive caching of service and host name
  12353. lookups. The latter provides better host name lookup performance,
  12354. resilience in the face of unreliable name servers, and also better
  12355. privacy---often the result of host name lookups is in local cache, so
  12356. external name servers do not even need to be queried.
  12357. @end defvr
  12358. @anchor{syslog-configuration-type}
  12359. @cindex syslog
  12360. @cindex logging
  12361. @deftp {Data Type} syslog-configuration
  12362. This data type represents the configuration of the syslog daemon.
  12363. @table @asis
  12364. @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
  12365. The syslog daemon to use.
  12366. @item @code{config-file} (default: @code{%default-syslog.conf})
  12367. The syslog configuration file to use.
  12368. @end table
  12369. @end deftp
  12370. @anchor{syslog-service}
  12371. @cindex syslog
  12372. @deffn {Scheme Procedure} syslog-service @var{config}
  12373. Return a service that runs a syslog daemon according to @var{config}.
  12374. @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
  12375. information on the configuration file syntax.
  12376. @end deffn
  12377. @defvr {Scheme Variable} guix-service-type
  12378. This is the type of the service that runs the build daemon,
  12379. @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
  12380. @code{guix-configuration} record as described below.
  12381. @end defvr
  12382. @anchor{guix-configuration-type}
  12383. @deftp {Data Type} guix-configuration
  12384. This data type represents the configuration of the Guix build daemon.
  12385. @xref{Invoking guix-daemon}, for more information.
  12386. @table @asis
  12387. @item @code{guix} (default: @var{guix})
  12388. The Guix package to use.
  12389. @item @code{build-group} (default: @code{"guixbuild"})
  12390. Name of the group for build user accounts.
  12391. @item @code{build-accounts} (default: @code{10})
  12392. Number of build user accounts to create.
  12393. @item @code{authorize-key?} (default: @code{#t})
  12394. @cindex substitutes, authorization thereof
  12395. Whether to authorize the substitute keys listed in
  12396. @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
  12397. (@pxref{Substitutes}).
  12398. When @code{authorize-key?} is true, @file{/etc/guix/acl} cannot be
  12399. changed by invoking @command{guix archive --authorize}. You must
  12400. instead adjust @code{guix-configuration} as you wish and reconfigure the
  12401. system. This ensures that your operating system configuration file is
  12402. self-contained.
  12403. @quotation Note
  12404. When booting or reconfiguring to a system where @code{authorize-key?}
  12405. is true, the existing @file{/etc/guix/acl} file is backed up as
  12406. @file{/etc/guix/acl.bak} if it was determined to be a manually modified
  12407. file. This is to facilitate migration from earlier versions, which
  12408. allowed for in-place modifications to @file{/etc/guix/acl}.
  12409. @end quotation
  12410. @vindex %default-authorized-guix-keys
  12411. @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
  12412. The list of authorized key files for archive imports, as a list of
  12413. string-valued gexps (@pxref{Invoking guix archive}). By default, it
  12414. contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
  12415. See @code{substitute-urls} below for an example on how to change it.
  12416. @item @code{use-substitutes?} (default: @code{#t})
  12417. Whether to use substitutes.
  12418. @item @code{substitute-urls} (default: @code{%default-substitute-urls})
  12419. The list of URLs where to look for substitutes by default.
  12420. Suppose you would like to fetch substitutes from @code{guix.example.org}
  12421. in addition to @code{@value{SUBSTITUTE-SERVER}}. You will need to do
  12422. two things: (1) add @code{guix.example.org} to @code{substitute-urls},
  12423. and (2) authorize its signing key, having done appropriate checks
  12424. (@pxref{Substitute Server Authorization}). The configuration below does
  12425. exactly that:
  12426. @lisp
  12427. (guix-configuration
  12428. (substitute-urls
  12429. (append (list "https://guix.example.org")
  12430. %default-substitute-urls))
  12431. (authorized-keys
  12432. (append (list (local-file "./guix.example.org-key.pub"))
  12433. %default-authorized-guix-keys)))
  12434. @end lisp
  12435. This example assumes that the file @file{./guix.example.org-key.pub}
  12436. contains the public key that @code{guix.example.org} uses to sign
  12437. substitutes.
  12438. @item @code{max-silent-time} (default: @code{0})
  12439. @itemx @code{timeout} (default: @code{0})
  12440. The number of seconds of silence and the number of seconds of activity,
  12441. respectively, after which a build process times out. A value of zero
  12442. disables the timeout.
  12443. @item @code{log-compression} (default: @code{'bzip2})
  12444. The type of compression used for build logs---one of @code{gzip},
  12445. @code{bzip2}, or @code{none}.
  12446. @item @code{discover?} (default: @code{#f})
  12447. Whether to discover substitute servers on the local network using mDNS
  12448. and DNS-SD.
  12449. @item @code{extra-options} (default: @code{'()})
  12450. List of extra command-line options for @command{guix-daemon}.
  12451. @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
  12452. File where @command{guix-daemon}'s standard output and standard error
  12453. are written.
  12454. @cindex HTTP proxy, for @code{guix-daemon}
  12455. @cindex proxy, for @code{guix-daemon} HTTP access
  12456. @item @code{http-proxy} (default: @code{#f})
  12457. The URL of the HTTP and HTTPS proxy used for downloading fixed-output
  12458. derivations and substitutes.
  12459. It is also possible to change the daemon's proxy at run time through the
  12460. @code{set-http-proxy} action, which restarts it:
  12461. @example
  12462. herd set-http-proxy guix-daemon http://localhost:8118
  12463. @end example
  12464. To clear the proxy settings, run:
  12465. @example
  12466. herd set-http-proxy guix-daemon
  12467. @end example
  12468. @item @code{tmpdir} (default: @code{#f})
  12469. A directory path where the @command{guix-daemon} will perform builds.
  12470. @end table
  12471. @end deftp
  12472. @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
  12473. Run @var{udev}, which populates the @file{/dev} directory dynamically.
  12474. udev rules can be provided as a list of files through the @var{rules}
  12475. variable. The procedures @code{udev-rule}, @code{udev-rules-service}
  12476. and @code{file->udev-rule} from @code{(gnu services base)} simplify the
  12477. creation of such rule files.
  12478. The @command{herd rules udev} command, as root, returns the name of the
  12479. directory containing all the active udev rules.
  12480. @end deffn
  12481. @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
  12482. Return a udev-rule file named @var{file-name} containing the rules
  12483. defined by the @var{contents} literal.
  12484. In the following example, a rule for a USB device is defined to be
  12485. stored in the file @file{90-usb-thing.rules}. The rule runs a script
  12486. upon detecting a USB device with a given product identifier.
  12487. @lisp
  12488. (define %example-udev-rule
  12489. (udev-rule
  12490. "90-usb-thing.rules"
  12491. (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
  12492. "ATTR@{product@}==\"Example\", "
  12493. "RUN+=\"/path/to/script\"")))
  12494. @end lisp
  12495. @end deffn
  12496. @deffn {Scheme Procedure} udev-rules-service [@var{name} @var{rules}] @
  12497. [#:groups @var{groups}]
  12498. Return a service that extends @code{udev-service-type } with @var{rules}
  12499. and @code{account-service-type} with @var{groups} as system groups.
  12500. This works by creating a singleton service type
  12501. @code{@var{name}-udev-rules}, of which the returned service is an
  12502. instance.
  12503. Here we show how it can be used to extend @code{udev-service-type} with the
  12504. previously defined rule @code{%example-udev-rule}.
  12505. @lisp
  12506. (operating-system
  12507. ;; @dots{}
  12508. (services
  12509. (cons (udev-rules-service 'usb-thing %example-udev-rule)
  12510. %desktop-services)))
  12511. @end lisp
  12512. @end deffn
  12513. @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
  12514. Return a udev file named @var{file-name} containing the rules defined
  12515. within @var{file}, a file-like object.
  12516. The following example showcases how we can use an existing rule file.
  12517. @lisp
  12518. (use-modules (guix download) ;for url-fetch
  12519. (guix packages) ;for origin
  12520. @dots{})
  12521. (define %android-udev-rules
  12522. (file->udev-rule
  12523. "51-android-udev.rules"
  12524. (let ((version "20170910"))
  12525. (origin
  12526. (method url-fetch)
  12527. (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
  12528. "android-udev-rules/" version "/51-android.rules"))
  12529. (sha256
  12530. (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
  12531. @end lisp
  12532. @end deffn
  12533. Additionally, Guix package definitions can be included in @var{rules} in
  12534. order to extend the udev rules with the definitions found under their
  12535. @file{lib/udev/rules.d} sub-directory. In lieu of the previous
  12536. @var{file->udev-rule} example, we could have used the
  12537. @var{android-udev-rules} package which exists in Guix in the @code{(gnu
  12538. packages android)} module.
  12539. The following example shows how to use the @var{android-udev-rules}
  12540. package so that the Android tool @command{adb} can detect devices
  12541. without root privileges. It also details how to create the
  12542. @code{adbusers} group, which is required for the proper functioning of
  12543. the rules defined within the @code{android-udev-rules} package. To
  12544. create such a group, we must define it both as part of the
  12545. @code{supplementary-groups} of our @code{user-account} declaration, as
  12546. well as in the @var{groups} of the @code{udev-rules-service} procedure.
  12547. @lisp
  12548. (use-modules (gnu packages android) ;for android-udev-rules
  12549. (gnu system shadow) ;for user-group
  12550. @dots{})
  12551. (operating-system
  12552. ;; @dots{}
  12553. (users (cons (user-account
  12554. ;; @dots{}
  12555. (supplementary-groups
  12556. '("adbusers" ;for adb
  12557. "wheel" "netdev" "audio" "video")))))
  12558. ;; @dots{}
  12559. (services
  12560. (cons (udev-rules-service 'android android-udev-rules
  12561. #:groups '("adbusers"))
  12562. %desktop-services)))
  12563. @end lisp
  12564. @defvr {Scheme Variable} urandom-seed-service-type
  12565. Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
  12566. when rebooting. It also tries to seed @file{/dev/urandom} from
  12567. @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
  12568. readable.
  12569. @end defvr
  12570. @defvr {Scheme Variable} %random-seed-file
  12571. This is the name of the file where some random bytes are saved by
  12572. @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
  12573. It defaults to @file{/var/lib/random-seed}.
  12574. @end defvr
  12575. @cindex mouse
  12576. @cindex gpm
  12577. @defvr {Scheme Variable} gpm-service-type
  12578. This is the type of the service that runs GPM, the @dfn{general-purpose
  12579. mouse daemon}, which provides mouse support to the Linux console. GPM
  12580. allows users to use the mouse in the console, notably to select, copy,
  12581. and paste text.
  12582. The value for services of this type must be a @code{gpm-configuration}
  12583. (see below). This service is not part of @code{%base-services}.
  12584. @end defvr
  12585. @deftp {Data Type} gpm-configuration
  12586. Data type representing the configuration of GPM.
  12587. @table @asis
  12588. @item @code{options} (default: @code{%default-gpm-options})
  12589. Command-line options passed to @command{gpm}. The default set of
  12590. options instruct @command{gpm} to listen to mouse events on
  12591. @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
  12592. more information.
  12593. @item @code{gpm} (default: @code{gpm})
  12594. The GPM package to use.
  12595. @end table
  12596. @end deftp
  12597. @anchor{guix-publish-service-type}
  12598. @deffn {Scheme Variable} guix-publish-service-type
  12599. This is the service type for @command{guix publish} (@pxref{Invoking
  12600. guix publish}). Its value must be a @code{guix-publish-configuration}
  12601. object, as described below.
  12602. This assumes that @file{/etc/guix} already contains a signing key pair as
  12603. created by @command{guix archive --generate-key} (@pxref{Invoking guix
  12604. archive}). If that is not the case, the service will fail to start.
  12605. @end deffn
  12606. @deftp {Data Type} guix-publish-configuration
  12607. Data type representing the configuration of the @code{guix publish}
  12608. service.
  12609. @table @asis
  12610. @item @code{guix} (default: @code{guix})
  12611. The Guix package to use.
  12612. @item @code{port} (default: @code{80})
  12613. The TCP port to listen for connections.
  12614. @item @code{host} (default: @code{"localhost"})
  12615. The host (and thus, network interface) to listen to. Use
  12616. @code{"0.0.0.0"} to listen on all the network interfaces.
  12617. @item @code{advertise?} (default: @code{#f})
  12618. When true, advertise the service on the local network @i{via} the DNS-SD
  12619. protocol, using Avahi.
  12620. This allows neighboring Guix devices with discovery on (see
  12621. @code{guix-configuration} above) to discover this @command{guix publish}
  12622. instance and to automatically download substitutes from it.
  12623. @item @code{compression} (default: @code{'(("gzip" 3))})
  12624. This is a list of compression method/level tuple used when compressing
  12625. substitutes. For example, to compress all substitutes with @emph{both} lzip
  12626. at level 7 and gzip at level 9, write:
  12627. @lisp
  12628. '(("lzip" 7) ("gzip" 9))
  12629. @end lisp
  12630. Level 9 achieves the best compression ratio at the expense of increased CPU
  12631. usage, whereas level 1 achieves fast compression. @xref{Invoking guix
  12632. publish}, for more information on the available compression methods and
  12633. the tradeoffs involved.
  12634. An empty list disables compression altogether.
  12635. @item @code{nar-path} (default: @code{"nar"})
  12636. The URL path at which ``nars'' can be fetched. @xref{Invoking guix
  12637. publish, @option{--nar-path}}, for details.
  12638. @item @code{cache} (default: @code{#f})
  12639. When it is @code{#f}, disable caching and instead generate archives on
  12640. demand. Otherwise, this should be the name of a directory---e.g.,
  12641. @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
  12642. archives and meta-data ready to be sent. @xref{Invoking guix publish,
  12643. @option{--cache}}, for more information on the tradeoffs involved.
  12644. @item @code{workers} (default: @code{#f})
  12645. When it is an integer, this is the number of worker threads used for
  12646. caching; when @code{#f}, the number of processors is used.
  12647. @xref{Invoking guix publish, @option{--workers}}, for more information.
  12648. @item @code{cache-bypass-threshold} (default: 10 MiB)
  12649. When @code{cache} is true, this is the maximum size in bytes of a store
  12650. item for which @command{guix publish} may bypass its cache in case of a
  12651. cache miss. @xref{Invoking guix publish,
  12652. @option{--cache-bypass-threshold}}, for more information.
  12653. @item @code{ttl} (default: @code{#f})
  12654. When it is an integer, this denotes the @dfn{time-to-live} in seconds
  12655. of the published archives. @xref{Invoking guix publish, @option{--ttl}},
  12656. for more information.
  12657. @end table
  12658. @end deftp
  12659. @anchor{rngd-service}
  12660. @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
  12661. [#:device "/dev/hwrng"]
  12662. Return a service that runs the @command{rngd} program from @var{rng-tools}
  12663. to add @var{device} to the kernel's entropy pool. The service will fail if
  12664. @var{device} does not exist.
  12665. @end deffn
  12666. @anchor{pam-limits-service}
  12667. @cindex session limits
  12668. @cindex ulimit
  12669. @cindex priority
  12670. @cindex realtime
  12671. @cindex jackd
  12672. @cindex nofile
  12673. @cindex open file descriptors
  12674. @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
  12675. Return a service that installs a configuration file for the
  12676. @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
  12677. @code{pam_limits} module}. The procedure optionally takes a list of
  12678. @code{pam-limits-entry} values, which can be used to specify
  12679. @code{ulimit} limits and @code{nice} priority limits to user sessions.
  12680. The following limits definition sets two hard and soft limits for all
  12681. login sessions of users in the @code{realtime} group:
  12682. @lisp
  12683. (pam-limits-service
  12684. (list
  12685. (pam-limits-entry "@@realtime" 'both 'rtprio 99)
  12686. (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
  12687. @end lisp
  12688. The first entry increases the maximum realtime priority for
  12689. non-privileged processes; the second entry lifts any restriction of the
  12690. maximum address space that can be locked in memory. These settings are
  12691. commonly used for real-time audio systems.
  12692. Another useful example is raising the maximum number of open file
  12693. descriptors that can be used:
  12694. @lisp
  12695. (pam-limits-service
  12696. (list
  12697. (pam-limits-entry "*" 'both 'nofile 100000)))
  12698. @end lisp
  12699. In the above example, the asterisk means the limit should apply to any
  12700. user. It is important to ensure the chosen value doesn't exceed the
  12701. maximum system value visible in the @file{/proc/sys/fs/file-max} file,
  12702. else the users would be prevented from login in. For more information
  12703. about the Pluggable Authentication Module (PAM) limits, refer to the
  12704. @samp{pam_limits} man page from the @code{linux-pam} package.
  12705. @end deffn
  12706. @node Scheduled Job Execution
  12707. @subsection Scheduled Job Execution
  12708. @cindex cron
  12709. @cindex mcron
  12710. @cindex scheduling jobs
  12711. The @code{(gnu services mcron)} module provides an interface to
  12712. GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
  12713. mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
  12714. Unix @command{cron} daemon; the main difference is that it is
  12715. implemented in Guile Scheme, which provides a lot of flexibility when
  12716. specifying the scheduling of jobs and their actions.
  12717. The example below defines an operating system that runs the
  12718. @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
  12719. and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
  12720. well as the @command{mkid} command on behalf of an unprivileged user
  12721. (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
  12722. gexps to introduce job definitions that are passed to mcron
  12723. (@pxref{G-Expressions}).
  12724. @lisp
  12725. (use-modules (guix) (gnu) (gnu services mcron))
  12726. (use-package-modules base idutils)
  12727. (define updatedb-job
  12728. ;; Run 'updatedb' at 3AM every day. Here we write the
  12729. ;; job's action as a Scheme procedure.
  12730. #~(job '(next-hour '(3))
  12731. (lambda ()
  12732. (execl (string-append #$findutils "/bin/updatedb")
  12733. "updatedb"
  12734. "--prunepaths=/tmp /var/tmp /gnu/store"))))
  12735. (define garbage-collector-job
  12736. ;; Collect garbage 5 minutes after midnight every day.
  12737. ;; The job's action is a shell command.
  12738. #~(job "5 0 * * *" ;Vixie cron syntax
  12739. "guix gc -F 1G"))
  12740. (define idutils-job
  12741. ;; Update the index database as user "charlie" at 12:15PM
  12742. ;; and 19:15PM. This runs from the user's home directory.
  12743. #~(job '(next-minute-from (next-hour '(12 19)) '(15))
  12744. (string-append #$idutils "/bin/mkid src")
  12745. #:user "charlie"))
  12746. (operating-system
  12747. ;; @dots{}
  12748. ;; %BASE-SERVICES already includes an instance of
  12749. ;; 'mcron-service-type', which we extend with additional
  12750. ;; jobs using 'simple-service'.
  12751. (services (cons (simple-service 'my-cron-jobs
  12752. mcron-service-type
  12753. (list garbage-collector-job
  12754. updatedb-job
  12755. idutils-job))
  12756. %base-services)))
  12757. @end lisp
  12758. For more complex jobs defined in Scheme where you need control over the top
  12759. level, for instance to introduce a @code{use-modules} form, you can move your
  12760. code to a separate program using the @code{program-file} procedure of the
  12761. @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
  12762. illustrates that.
  12763. @lisp
  12764. (define %battery-alert-job
  12765. ;; Beep when the battery percentage falls below %MIN-LEVEL.
  12766. #~(job
  12767. '(next-minute (range 0 60 1))
  12768. #$(program-file
  12769. "battery-alert.scm"
  12770. (with-imported-modules (source-module-closure
  12771. '((guix build utils)))
  12772. #~(begin
  12773. (use-modules (guix build utils)
  12774. (ice-9 popen)
  12775. (ice-9 regex)
  12776. (ice-9 textual-ports)
  12777. (srfi srfi-2))
  12778. (define %min-level 20)
  12779. (setenv "LC_ALL" "C") ;ensure English output
  12780. (and-let* ((input-pipe (open-pipe*
  12781. OPEN_READ
  12782. #$(file-append acpi "/bin/acpi")))
  12783. (output (get-string-all input-pipe))
  12784. (m (string-match "Discharging, ([0-9]+)%" output))
  12785. (level (string->number (match:substring m 1)))
  12786. ((< level %min-level)))
  12787. (format #t "warning: Battery level is low (~a%)~%" level)
  12788. (invoke #$(file-append beep "/bin/beep") "-r5")))))))
  12789. @end lisp
  12790. @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
  12791. for more information on mcron job specifications. Below is the
  12792. reference of the mcron service.
  12793. On a running system, you can use the @code{schedule} action of the service to
  12794. visualize the mcron jobs that will be executed next:
  12795. @example
  12796. # herd schedule mcron
  12797. @end example
  12798. @noindent
  12799. The example above lists the next five tasks that will be executed, but you can
  12800. also specify the number of tasks to display:
  12801. @example
  12802. # herd schedule mcron 10
  12803. @end example
  12804. @defvr {Scheme Variable} mcron-service-type
  12805. This is the type of the @code{mcron} service, whose value is an
  12806. @code{mcron-configuration} object.
  12807. This service type can be the target of a service extension that provides
  12808. it additional job specifications (@pxref{Service Composition}). In
  12809. other words, it is possible to define services that provide additional
  12810. mcron jobs to run.
  12811. @end defvr
  12812. @deftp {Data Type} mcron-configuration
  12813. Data type representing the configuration of mcron.
  12814. @table @asis
  12815. @item @code{mcron} (default: @var{mcron})
  12816. The mcron package to use.
  12817. @item @code{jobs}
  12818. This is a list of gexps (@pxref{G-Expressions}), where each gexp
  12819. corresponds to an mcron job specification (@pxref{Syntax, mcron job
  12820. specifications,, mcron, GNU@tie{}mcron}).
  12821. @end table
  12822. @end deftp
  12823. @node Log Rotation
  12824. @subsection Log Rotation
  12825. @cindex rottlog
  12826. @cindex log rotation
  12827. @cindex logging
  12828. Log files such as those found in @file{/var/log} tend to grow endlessly,
  12829. so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
  12830. their contents in separate files, possibly compressed. The @code{(gnu
  12831. services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
  12832. log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
  12833. This service is part of @code{%base-services}, and thus enabled by
  12834. default, with the default settings, for commonly encountered log files.
  12835. The example below shows how to extend it with an additional
  12836. @dfn{rotation}, should you need to do that (usually, services that
  12837. produce log files already take care of that):
  12838. @lisp
  12839. (use-modules (guix) (gnu))
  12840. (use-service-modules admin)
  12841. (define my-log-files
  12842. ;; Log files that I want to rotate.
  12843. '("/var/log/something.log" "/var/log/another.log"))
  12844. (operating-system
  12845. ;; @dots{}
  12846. (services (cons (simple-service 'rotate-my-stuff
  12847. rottlog-service-type
  12848. (list (log-rotation
  12849. (frequency 'daily)
  12850. (files my-log-files))))
  12851. %base-services)))
  12852. @end lisp
  12853. @defvr {Scheme Variable} rottlog-service-type
  12854. This is the type of the Rottlog service, whose value is a
  12855. @code{rottlog-configuration} object.
  12856. Other services can extend this one with new @code{log-rotation} objects
  12857. (see below), thereby augmenting the set of files to be rotated.
  12858. This service type can define mcron jobs (@pxref{Scheduled Job
  12859. Execution}) to run the rottlog service.
  12860. @end defvr
  12861. @deftp {Data Type} rottlog-configuration
  12862. Data type representing the configuration of rottlog.
  12863. @table @asis
  12864. @item @code{rottlog} (default: @code{rottlog})
  12865. The Rottlog package to use.
  12866. @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
  12867. The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
  12868. rottlog, GNU Rot[t]log Manual}).
  12869. @item @code{rotations} (default: @code{%default-rotations})
  12870. A list of @code{log-rotation} objects as defined below.
  12871. @item @code{jobs}
  12872. This is a list of gexps where each gexp corresponds to an mcron job
  12873. specification (@pxref{Scheduled Job Execution}).
  12874. @end table
  12875. @end deftp
  12876. @deftp {Data Type} log-rotation
  12877. Data type representing the rotation of a group of log files.
  12878. Taking an example from the Rottlog manual (@pxref{Period Related File
  12879. Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
  12880. defined like this:
  12881. @lisp
  12882. (log-rotation
  12883. (frequency 'daily)
  12884. (files '("/var/log/apache/*"))
  12885. (options '("storedir apache-archives"
  12886. "rotate 6"
  12887. "notifempty"
  12888. "nocompress")))
  12889. @end lisp
  12890. The list of fields is as follows:
  12891. @table @asis
  12892. @item @code{frequency} (default: @code{'weekly})
  12893. The log rotation frequency, a symbol.
  12894. @item @code{files}
  12895. The list of files or file glob patterns to rotate.
  12896. @item @code{options} (default: @code{'()})
  12897. The list of rottlog options for this rotation (@pxref{Configuration
  12898. parameters,,, rottlog, GNU Rot[t]lg Manual}).
  12899. @item @code{post-rotate} (default: @code{#f})
  12900. Either @code{#f} or a gexp to execute once the rotation has completed.
  12901. @end table
  12902. @end deftp
  12903. @defvr {Scheme Variable} %default-rotations
  12904. Specifies weekly rotation of @code{%rotated-files} and of
  12905. @file{/var/log/guix-daemon.log}.
  12906. @end defvr
  12907. @defvr {Scheme Variable} %rotated-files
  12908. The list of syslog-controlled files to be rotated. By default it is:
  12909. @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
  12910. "/var/log/maillog")}.
  12911. @end defvr
  12912. @node Networking Services
  12913. @subsection Networking Services
  12914. The @code{(gnu services networking)} module provides services to configure
  12915. the network interface.
  12916. @cindex DHCP, networking service
  12917. @defvr {Scheme Variable} dhcp-client-service-type
  12918. This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
  12919. Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
  12920. is the DHCP client package to use, @code{isc-dhcp} by default.
  12921. @end defvr
  12922. @deffn {Scheme Procedure} dhcpd-service-type
  12923. This type defines a service that runs a DHCP daemon. To create a
  12924. service of this type, you must supply a @code{<dhcpd-configuration>}.
  12925. For example:
  12926. @lisp
  12927. (service dhcpd-service-type
  12928. (dhcpd-configuration
  12929. (config-file (local-file "my-dhcpd.conf"))
  12930. (interfaces '("enp0s25"))))
  12931. @end lisp
  12932. @end deffn
  12933. @deftp {Data Type} dhcpd-configuration
  12934. @table @asis
  12935. @item @code{package} (default: @code{isc-dhcp})
  12936. The package that provides the DHCP daemon. This package is expected to
  12937. provide the daemon at @file{sbin/dhcpd} relative to its output
  12938. directory. The default package is the
  12939. @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
  12940. @item @code{config-file} (default: @code{#f})
  12941. The configuration file to use. This is required. It will be passed to
  12942. @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
  12943. object (@pxref{G-Expressions, file-like objects}). See @code{man
  12944. dhcpd.conf} for details on the configuration file syntax.
  12945. @item @code{version} (default: @code{"4"})
  12946. The DHCP version to use. The ISC DHCP server supports the values ``4'',
  12947. ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
  12948. options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
  12949. details.
  12950. @item @code{run-directory} (default: @code{"/run/dhcpd"})
  12951. The run directory to use. At service activation time, this directory
  12952. will be created if it does not exist.
  12953. @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
  12954. The PID file to use. This corresponds to the @code{-pf} option of
  12955. @code{dhcpd}. See @code{man dhcpd} for details.
  12956. @item @code{interfaces} (default: @code{'()})
  12957. The names of the network interfaces on which dhcpd should listen for
  12958. broadcasts. If this list is not empty, then its elements (which must be
  12959. strings) will be appended to the @code{dhcpd} invocation when starting
  12960. the daemon. It may not be necessary to explicitly specify any
  12961. interfaces here; see @code{man dhcpd} for details.
  12962. @end table
  12963. @end deftp
  12964. @defvr {Scheme Variable} static-networking-service-type
  12965. This is the type for statically-configured network interfaces.
  12966. @c TODO Document <static-networking> data structures.
  12967. @end defvr
  12968. @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
  12969. [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
  12970. [#:requirement @code{'(udev)}]
  12971. Return a service that starts @var{interface} with address @var{ip}. If
  12972. @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
  12973. it must be a string specifying the default network gateway. @var{requirement}
  12974. can be used to declare a dependency on another service before configuring the
  12975. interface.
  12976. This procedure can be called several times, one for each network
  12977. interface of interest. Behind the scenes what it does is extend
  12978. @code{static-networking-service-type} with additional network interfaces
  12979. to handle.
  12980. For example:
  12981. @lisp
  12982. (static-networking-service "eno1" "192.168.1.82"
  12983. #:gateway "192.168.1.2"
  12984. #:name-servers '("192.168.1.2"))
  12985. @end lisp
  12986. @end deffn
  12987. @cindex wicd
  12988. @cindex wireless
  12989. @cindex WiFi
  12990. @cindex network management
  12991. @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
  12992. Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
  12993. management daemon that aims to simplify wired and wireless networking.
  12994. This service adds the @var{wicd} package to the global profile, providing
  12995. several commands to interact with the daemon and configure networking:
  12996. @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
  12997. and @command{wicd-curses} user interfaces.
  12998. @end deffn
  12999. @cindex ModemManager
  13000. @defvr {Scheme Variable} modem-manager-service-type
  13001. This is the service type for the
  13002. @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
  13003. service. The value for this service type is a
  13004. @code{modem-manager-configuration} record.
  13005. This service is part of @code{%desktop-services} (@pxref{Desktop
  13006. Services}).
  13007. @end defvr
  13008. @deftp {Data Type} modem-manager-configuration
  13009. Data type representing the configuration of ModemManager.
  13010. @table @asis
  13011. @item @code{modem-manager} (default: @code{modem-manager})
  13012. The ModemManager package to use.
  13013. @end table
  13014. @end deftp
  13015. @cindex USB_ModeSwitch
  13016. @cindex Modeswitching
  13017. @defvr {Scheme Variable} usb-modeswitch-service-type
  13018. This is the service type for the
  13019. @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch}
  13020. service. The value for this service type is
  13021. a @code{usb-modeswitch-configuration} record.
  13022. When plugged in, some USB modems (and other USB devices) initially present
  13023. themselves as a read-only storage medium and not as a modem. They need to be
  13024. @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
  13025. installs udev rules to automatically modeswitch these devices when they are
  13026. plugged in.
  13027. This service is part of @code{%desktop-services} (@pxref{Desktop
  13028. Services}).
  13029. @end defvr
  13030. @deftp {Data Type} usb-modeswitch-configuration
  13031. Data type representing the configuration of USB_ModeSwitch.
  13032. @table @asis
  13033. @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
  13034. The USB_ModeSwitch package providing the binaries for modeswitching.
  13035. @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
  13036. The package providing the device data and udev rules file used by
  13037. USB_ModeSwitch.
  13038. @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
  13039. Which config file to use for the USB_ModeSwitch dispatcher. By default the
  13040. config file shipped with USB_ModeSwitch is used which disables logging to
  13041. @file{/var/log} among other default settings. If set to @code{#f}, no config
  13042. file is used.
  13043. @end table
  13044. @end deftp
  13045. @cindex NetworkManager
  13046. @defvr {Scheme Variable} network-manager-service-type
  13047. This is the service type for the
  13048. @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
  13049. service. The value for this service type is a
  13050. @code{network-manager-configuration} record.
  13051. This service is part of @code{%desktop-services} (@pxref{Desktop
  13052. Services}).
  13053. @end defvr
  13054. @deftp {Data Type} network-manager-configuration
  13055. Data type representing the configuration of NetworkManager.
  13056. @table @asis
  13057. @item @code{network-manager} (default: @code{network-manager})
  13058. The NetworkManager package to use.
  13059. @item @code{dns} (default: @code{"default"})
  13060. Processing mode for DNS, which affects how NetworkManager uses the
  13061. @code{resolv.conf} configuration file.
  13062. @table @samp
  13063. @item default
  13064. NetworkManager will update @code{resolv.conf} to reflect the nameservers
  13065. provided by currently active connections.
  13066. @item dnsmasq
  13067. NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
  13068. @dfn{conditional forwarding} configuration if you are connected to a VPN, and
  13069. then update @code{resolv.conf} to point to the local nameserver.
  13070. With this setting, you can share your network connection. For example when
  13071. you want to share your network connection to another laptop @i{via} an
  13072. Ethernet cable, you can open @command{nm-connection-editor} and configure the
  13073. Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
  13074. and reestablish the connection (or reboot).
  13075. You can also set up a @dfn{host-to-guest connection} to QEMU VMs
  13076. (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
  13077. e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
  13078. browser on your host system, or connect to the VM @i{via} SSH
  13079. (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
  13080. host-to-guest connection, run this command once:
  13081. @example
  13082. nmcli connection add type tun \
  13083. connection.interface-name tap0 \
  13084. tun.mode tap tun.owner $(id -u) \
  13085. ipv4.method shared \
  13086. ipv4.addresses 172.28.112.1/24
  13087. @end example
  13088. Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
  13089. @option{-nic tap,ifname=tap0,script=no,downscript=no} to
  13090. @command{qemu-system-...}.
  13091. @item none
  13092. NetworkManager will not modify @code{resolv.conf}.
  13093. @end table
  13094. @item @code{vpn-plugins} (default: @code{'()})
  13095. This is the list of available plugins for virtual private networks
  13096. (VPNs). An example of this is the @code{network-manager-openvpn}
  13097. package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
  13098. @end table
  13099. @end deftp
  13100. @cindex Connman
  13101. @deffn {Scheme Variable} connman-service-type
  13102. This is the service type to run @url{https://01.org/connman,Connman},
  13103. a network connection manager.
  13104. Its value must be an
  13105. @code{connman-configuration} record as in this example:
  13106. @lisp
  13107. (service connman-service-type
  13108. (connman-configuration
  13109. (disable-vpn? #t)))
  13110. @end lisp
  13111. See below for details about @code{connman-configuration}.
  13112. @end deffn
  13113. @deftp {Data Type} connman-configuration
  13114. Data Type representing the configuration of connman.
  13115. @table @asis
  13116. @item @code{connman} (default: @var{connman})
  13117. The connman package to use.
  13118. @item @code{disable-vpn?} (default: @code{#f})
  13119. When true, disable connman's vpn plugin.
  13120. @end table
  13121. @end deftp
  13122. @cindex WPA Supplicant
  13123. @defvr {Scheme Variable} wpa-supplicant-service-type
  13124. This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
  13125. supplicant}, an authentication daemon required to authenticate against
  13126. encrypted WiFi or ethernet networks.
  13127. @end defvr
  13128. @deftp {Data Type} wpa-supplicant-configuration
  13129. Data type representing the configuration of WPA Supplicant.
  13130. It takes the following parameters:
  13131. @table @asis
  13132. @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
  13133. The WPA Supplicant package to use.
  13134. @item @code{requirement} (default: @code{'(user-processes loopback syslogd)}
  13135. List of services that should be started before WPA Supplicant starts.
  13136. @item @code{dbus?} (default: @code{#t})
  13137. Whether to listen for requests on D-Bus.
  13138. @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
  13139. Where to store the PID file.
  13140. @item @code{interface} (default: @code{#f})
  13141. If this is set, it must specify the name of a network interface that
  13142. WPA supplicant will control.
  13143. @item @code{config-file} (default: @code{#f})
  13144. Optional configuration file to use.
  13145. @item @code{extra-options} (default: @code{'()})
  13146. List of additional command-line arguments to pass to the daemon.
  13147. @end table
  13148. @end deftp
  13149. @cindex hostapd service, for Wi-Fi access points
  13150. @cindex Wi-Fi access points, hostapd service
  13151. @defvr {Scheme Variable} hostapd-service-type
  13152. This is the service type to run the @uref{https://w1.fi/hostapd/,
  13153. hostapd} daemon to set up WiFi (IEEE 802.11) access points and
  13154. authentication servers. Its associated value must be a
  13155. @code{hostapd-configuration} as shown below:
  13156. @lisp
  13157. ;; Use wlan1 to run the access point for "My Network".
  13158. (service hostapd-service-type
  13159. (hostapd-configuration
  13160. (interface "wlan1")
  13161. (ssid "My Network")
  13162. (channel 12)))
  13163. @end lisp
  13164. @end defvr
  13165. @deftp {Data Type} hostapd-configuration
  13166. This data type represents the configuration of the hostapd service, with
  13167. the following fields:
  13168. @table @asis
  13169. @item @code{package} (default: @code{hostapd})
  13170. The hostapd package to use.
  13171. @item @code{interface} (default: @code{"wlan0"})
  13172. The network interface to run the WiFi access point.
  13173. @item @code{ssid}
  13174. The SSID (@dfn{service set identifier}), a string that identifies this
  13175. network.
  13176. @item @code{broadcast-ssid?} (default: @code{#t})
  13177. Whether to broadcast this SSID.
  13178. @item @code{channel} (default: @code{1})
  13179. The WiFi channel to use.
  13180. @item @code{driver} (default: @code{"nl80211"})
  13181. The driver interface type. @code{"nl80211"} is used with all Linux
  13182. mac80211 drivers. Use @code{"none"} if building hostapd as a standalone
  13183. RADIUS server that does # not control any wireless/wired driver.
  13184. @item @code{extra-settings} (default: @code{""})
  13185. Extra settings to append as-is to the hostapd configuration file. See
  13186. @uref{https://w1.fi/cgit/hostap/plain/hostapd/hostapd.conf} for the
  13187. configuration file reference.
  13188. @end table
  13189. @end deftp
  13190. @defvr {Scheme Variable} simulated-wifi-service-type
  13191. This is the type of a service to simulate WiFi networking, which can be
  13192. useful in virtual machines for testing purposes. The service loads the
  13193. Linux kernel
  13194. @uref{https://www.kernel.org/doc/html/latest/networking/mac80211_hwsim/mac80211_hwsim.html,
  13195. @code{mac80211_hwsim} module} and starts hostapd to create a pseudo WiFi
  13196. network that can be seen on @code{wlan0}, by default.
  13197. The service's value is a @code{hostapd-configuration} record.
  13198. @end defvr
  13199. @cindex iptables
  13200. @defvr {Scheme Variable} iptables-service-type
  13201. This is the service type to set up an iptables configuration. iptables is a
  13202. packet filtering framework supported by the Linux kernel. This service
  13203. supports configuring iptables for both IPv4 and IPv6. A simple example
  13204. configuration rejecting all incoming connections except those to the ssh port
  13205. 22 is shown below.
  13206. @lisp
  13207. (service iptables-service-type
  13208. (iptables-configuration
  13209. (ipv4-rules (plain-file "iptables.rules" "*filter
  13210. :INPUT ACCEPT
  13211. :FORWARD ACCEPT
  13212. :OUTPUT ACCEPT
  13213. -A INPUT -p tcp --dport 22 -j ACCEPT
  13214. -A INPUT -j REJECT --reject-with icmp-port-unreachable
  13215. COMMIT
  13216. "))
  13217. (ipv6-rules (plain-file "ip6tables.rules" "*filter
  13218. :INPUT ACCEPT
  13219. :FORWARD ACCEPT
  13220. :OUTPUT ACCEPT
  13221. -A INPUT -p tcp --dport 22 -j ACCEPT
  13222. -A INPUT -j REJECT --reject-with icmp6-port-unreachable
  13223. COMMIT
  13224. "))))
  13225. @end lisp
  13226. @end defvr
  13227. @deftp {Data Type} iptables-configuration
  13228. The data type representing the configuration of iptables.
  13229. @table @asis
  13230. @item @code{iptables} (default: @code{iptables})
  13231. The iptables package that provides @code{iptables-restore} and
  13232. @code{ip6tables-restore}.
  13233. @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
  13234. The iptables rules to use. It will be passed to @code{iptables-restore}.
  13235. This may be any ``file-like'' object (@pxref{G-Expressions, file-like
  13236. objects}).
  13237. @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
  13238. The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
  13239. This may be any ``file-like'' object (@pxref{G-Expressions, file-like
  13240. objects}).
  13241. @end table
  13242. @end deftp
  13243. @cindex nftables
  13244. @defvr {Scheme Variable} nftables-service-type
  13245. This is the service type to set up a nftables configuration. nftables is a
  13246. netfilter project that aims to replace the existing iptables, ip6tables,
  13247. arptables and ebtables framework. It provides a new packet filtering
  13248. framework, a new user-space utility @command{nft}, and a compatibility layer
  13249. for iptables. This service comes with a default ruleset
  13250. @code{%default-nftables-ruleset} that rejecting all incomming connections
  13251. except those to the ssh port 22. To use it, simply write:
  13252. @lisp
  13253. (service nftables-service-type)
  13254. @end lisp
  13255. @end defvr
  13256. @deftp {Data Type} nftables-configuration
  13257. The data type representing the configuration of nftables.
  13258. @table @asis
  13259. @item @code{package} (default: @code{nftables})
  13260. The nftables package that provides @command{nft}.
  13261. @item @code{ruleset} (default: @code{%default-nftables-ruleset})
  13262. The nftables ruleset to use. This may be any ``file-like'' object
  13263. (@pxref{G-Expressions, file-like objects}).
  13264. @end table
  13265. @end deftp
  13266. @cindex NTP (Network Time Protocol), service
  13267. @cindex ntpd, service for the Network Time Protocol daemon
  13268. @cindex real time clock
  13269. @defvr {Scheme Variable} ntp-service-type
  13270. This is the type of the service running the @uref{https://www.ntp.org,
  13271. Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
  13272. system clock synchronized with that of the specified NTP servers.
  13273. The value of this service is an @code{ntpd-configuration} object, as described
  13274. below.
  13275. @end defvr
  13276. @deftp {Data Type} ntp-configuration
  13277. This is the data type for the NTP service configuration.
  13278. @table @asis
  13279. @item @code{servers} (default: @code{%ntp-servers})
  13280. This is the list of servers (@code{<ntp-server>} records) with which
  13281. @command{ntpd} will be synchronized. See the @code{ntp-server} data type
  13282. definition below.
  13283. @item @code{allow-large-adjustment?} (default: @code{#t})
  13284. This determines whether @command{ntpd} is allowed to make an initial
  13285. adjustment of more than 1,000 seconds.
  13286. @item @code{ntp} (default: @code{ntp})
  13287. The NTP package to use.
  13288. @end table
  13289. @end deftp
  13290. @defvr {Scheme Variable} %ntp-servers
  13291. List of host names used as the default NTP servers. These are servers of the
  13292. @uref{https://www.ntppool.org/en/, NTP Pool Project}.
  13293. @end defvr
  13294. @deftp {Data Type} ntp-server
  13295. The data type representing the configuration of a NTP server.
  13296. @table @asis
  13297. @item @code{type} (default: @code{'server})
  13298. The type of the NTP server, given as a symbol. One of @code{'pool},
  13299. @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
  13300. @item @code{address}
  13301. The address of the server, as a string.
  13302. @item @code{options}
  13303. NTPD options to use with that specific server, given as a list of option names
  13304. and/or of option names and values tuples. The following example define a server
  13305. to use with the options @option{iburst} and @option{prefer}, as well as
  13306. @option{version} 3 and a @option{maxpoll} time of 16 seconds.
  13307. @example
  13308. (ntp-server
  13309. (type 'server)
  13310. (address "some.ntp.server.org")
  13311. (options `(iburst (version 3) (maxpoll 16) prefer))))
  13312. @end example
  13313. @end table
  13314. @end deftp
  13315. @cindex OpenNTPD
  13316. @deffn {Scheme Procedure} openntpd-service-type
  13317. Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
  13318. by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
  13319. clock synchronized with that of the given servers.
  13320. @lisp
  13321. (service
  13322. openntpd-service-type
  13323. (openntpd-configuration
  13324. (listen-on '("127.0.0.1" "::1"))
  13325. (sensor '("udcf0 correction 70000"))
  13326. (constraint-from '("www.gnu.org"))
  13327. (constraints-from '("https://www.google.com/"))))
  13328. @end lisp
  13329. @end deffn
  13330. @defvr {Scheme Variable} %openntpd-servers
  13331. This variable is a list of the server addresses defined in
  13332. @code{%ntp-servers}.
  13333. @end defvr
  13334. @deftp {Data Type} openntpd-configuration
  13335. @table @asis
  13336. @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
  13337. The openntpd executable to use.
  13338. @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
  13339. A list of local IP addresses or hostnames the ntpd daemon should listen on.
  13340. @item @code{query-from} (default: @code{'()})
  13341. A list of local IP address the ntpd daemon should use for outgoing queries.
  13342. @item @code{sensor} (default: @code{'()})
  13343. Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
  13344. will listen to each sensor that actually exists and ignore non-existent ones.
  13345. See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
  13346. information.
  13347. @item @code{server} (default: @code{'()})
  13348. Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
  13349. @item @code{servers} (default: @code{%openntp-servers})
  13350. Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
  13351. @item @code{constraint-from} (default: @code{'()})
  13352. @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
  13353. This time information is not used for precision but acts as an authenticated
  13354. constraint, thereby reducing the impact of unauthenticated NTP
  13355. man-in-the-middle attacks.
  13356. Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
  13357. a constraint.
  13358. @item @code{constraints-from} (default: @code{'()})
  13359. As with constraint from, specify a list of URLs, IP addresses or hostnames of
  13360. HTTPS servers to provide a constraint. Should the hostname resolve to multiple
  13361. IP addresses, @code{ntpd} will calculate a median constraint from all of them.
  13362. @end table
  13363. @end deftp
  13364. @cindex inetd
  13365. @deffn {Scheme variable} inetd-service-type
  13366. This service runs the @command{inetd} (@pxref{inetd invocation,,,
  13367. inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
  13368. connections on internet sockets, and lazily starts the specified server
  13369. program when a connection is made on one of these sockets.
  13370. The value of this service is an @code{inetd-configuration} object. The
  13371. following example configures the @command{inetd} daemon to provide the
  13372. built-in @command{echo} service, as well as an smtp service which
  13373. forwards smtp traffic over ssh to a server @code{smtp-server} behind a
  13374. gateway @code{hostname}:
  13375. @lisp
  13376. (service
  13377. inetd-service-type
  13378. (inetd-configuration
  13379. (entries (list
  13380. (inetd-entry
  13381. (name "echo")
  13382. (socket-type 'stream)
  13383. (protocol "tcp")
  13384. (wait? #f)
  13385. (user "root"))
  13386. (inetd-entry
  13387. (node "127.0.0.1")
  13388. (name "smtp")
  13389. (socket-type 'stream)
  13390. (protocol "tcp")
  13391. (wait? #f)
  13392. (user "root")
  13393. (program (file-append openssh "/bin/ssh"))
  13394. (arguments
  13395. '("ssh" "-qT" "-i" "/path/to/ssh_key"
  13396. "-W" "smtp-server:25" "user@@hostname")))))))
  13397. @end lisp
  13398. See below for more details about @code{inetd-configuration}.
  13399. @end deffn
  13400. @deftp {Data Type} inetd-configuration
  13401. Data type representing the configuration of @command{inetd}.
  13402. @table @asis
  13403. @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
  13404. The @command{inetd} executable to use.
  13405. @item @code{entries} (default: @code{'()})
  13406. A list of @command{inetd} service entries. Each entry should be created
  13407. by the @code{inetd-entry} constructor.
  13408. @end table
  13409. @end deftp
  13410. @deftp {Data Type} inetd-entry
  13411. Data type representing an entry in the @command{inetd} configuration.
  13412. Each entry corresponds to a socket where @command{inetd} will listen for
  13413. requests.
  13414. @table @asis
  13415. @item @code{node} (default: @code{#f})
  13416. Optional string, a comma-separated list of local addresses
  13417. @command{inetd} should use when listening for this service.
  13418. @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
  13419. description of all options.
  13420. @item @code{name}
  13421. A string, the name must correspond to an entry in @code{/etc/services}.
  13422. @item @code{socket-type}
  13423. One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
  13424. @code{'seqpacket}.
  13425. @item @code{protocol}
  13426. A string, must correspond to an entry in @code{/etc/protocols}.
  13427. @item @code{wait?} (default: @code{#t})
  13428. Whether @command{inetd} should wait for the server to exit before
  13429. listening to new service requests.
  13430. @item @code{user}
  13431. A string containing the user (and, optionally, group) name of the user
  13432. as whom the server should run. The group name can be specified in a
  13433. suffix, separated by a colon or period, i.e.@: @code{"user"},
  13434. @code{"user:group"} or @code{"user.group"}.
  13435. @item @code{program} (default: @code{"internal"})
  13436. The server program which will serve the requests, or @code{"internal"}
  13437. if @command{inetd} should use a built-in service.
  13438. @item @code{arguments} (default: @code{'()})
  13439. A list strings or file-like objects, which are the server program's
  13440. arguments, starting with the zeroth argument, i.e.@: the name of the
  13441. program itself. For @command{inetd}'s internal services, this entry
  13442. must be @code{'()} or @code{'("internal")}.
  13443. @end table
  13444. @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
  13445. detailed discussion of each configuration field.
  13446. @end deftp
  13447. @cindex Tor
  13448. @defvr {Scheme Variable} tor-service-type
  13449. This is the type for a service that runs the @uref{https://torproject.org,
  13450. Tor} anonymous networking daemon. The service is configured using a
  13451. @code{<tor-configuration>} record. By default, the Tor daemon runs as the
  13452. @code{tor} unprivileged user, which is a member of the @code{tor} group.
  13453. @end defvr
  13454. @deftp {Data Type} tor-configuration
  13455. @table @asis
  13456. @item @code{tor} (default: @code{tor})
  13457. The package that provides the Tor daemon. This package is expected to provide
  13458. the daemon at @file{bin/tor} relative to its output directory. The default
  13459. package is the @uref{https://www.torproject.org, Tor Project's}
  13460. implementation.
  13461. @item @code{config-file} (default: @code{(plain-file "empty" "")})
  13462. The configuration file to use. It will be appended to a default configuration
  13463. file, and the final configuration file will be passed to @code{tor} via its
  13464. @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
  13465. file-like objects}). See @code{man tor} for details on the configuration file
  13466. syntax.
  13467. @item @code{hidden-services} (default: @code{'()})
  13468. The list of @code{<hidden-service>} records to use. For any hidden service
  13469. you include in this list, appropriate configuration to enable the hidden
  13470. service will be automatically added to the default configuration file. You
  13471. may conveniently create @code{<hidden-service>} records using the
  13472. @code{tor-hidden-service} procedure described below.
  13473. @item @code{socks-socket-type} (default: @code{'tcp})
  13474. The default socket type that Tor should use for its SOCKS socket. This must
  13475. be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
  13476. Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
  13477. If it is @code{'unix}, then Tor will listen on the UNIX domain socket
  13478. @file{/var/run/tor/socks-sock}, which will be made writable by members of the
  13479. @code{tor} group.
  13480. If you want to customize the SOCKS socket in more detail, leave
  13481. @code{socks-socket-type} at its default value of @code{'tcp} and use
  13482. @code{config-file} to override the default by providing your own
  13483. @code{SocksPort} option.
  13484. @item @code{control-socket?} (default: @code{#f})
  13485. Whether or not to provide a ``control socket'' by which Tor can be
  13486. controlled to, for instance, dynamically instantiate tor onion services.
  13487. If @code{#t}, Tor will listen for control commands on the UNIX domain socket
  13488. @file{/var/run/tor/control-sock}, which will be made writable by members of the
  13489. @code{tor} group.
  13490. @end table
  13491. @end deftp
  13492. @cindex hidden service
  13493. @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
  13494. Define a new Tor @dfn{hidden service} called @var{name} and implementing
  13495. @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
  13496. @example
  13497. '((22 "127.0.0.1:22")
  13498. (80 "127.0.0.1:8080"))
  13499. @end example
  13500. In this example, port 22 of the hidden service is mapped to local port 22, and
  13501. port 80 is mapped to local port 8080.
  13502. This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
  13503. the @file{hostname} file contains the @code{.onion} host name for the hidden
  13504. service.
  13505. See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
  13506. project's documentation} for more information.
  13507. @end deffn
  13508. The @code{(gnu services rsync)} module provides the following services:
  13509. You might want an rsync daemon if you have files that you want available
  13510. so anyone (or just yourself) can download existing files or upload new
  13511. files.
  13512. @deffn {Scheme Variable} rsync-service-type
  13513. This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
  13514. The value for this service type is a
  13515. @command{rsync-configuration} record as in this example:
  13516. @lisp
  13517. (service rsync-service-type)
  13518. @end lisp
  13519. See below for details about @code{rsync-configuration}.
  13520. @end deffn
  13521. @deftp {Data Type} rsync-configuration
  13522. Data type representing the configuration for @code{rsync-service}.
  13523. @table @asis
  13524. @item @code{package} (default: @var{rsync})
  13525. @code{rsync} package to use.
  13526. @item @code{port-number} (default: @code{873})
  13527. TCP port on which @command{rsync} listens for incoming connections. If port
  13528. is less than @code{1024} @command{rsync} needs to be started as the
  13529. @code{root} user and group.
  13530. @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
  13531. Name of the file where @command{rsync} writes its PID.
  13532. @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
  13533. Name of the file where @command{rsync} writes its lock file.
  13534. @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
  13535. Name of the file where @command{rsync} writes its log file.
  13536. @item @code{use-chroot?} (default: @var{#t})
  13537. Whether to use chroot for @command{rsync} shared directory.
  13538. @item @code{share-path} (default: @file{/srv/rsync})
  13539. Location of the @command{rsync} shared directory.
  13540. @item @code{share-comment} (default: @code{"Rsync share"})
  13541. Comment of the @command{rsync} shared directory.
  13542. @item @code{read-only?} (default: @var{#f})
  13543. Read-write permissions to shared directory.
  13544. @item @code{timeout} (default: @code{300})
  13545. I/O timeout in seconds.
  13546. @item @code{user} (default: @var{"root"})
  13547. Owner of the @code{rsync} process.
  13548. @item @code{group} (default: @var{"root"})
  13549. Group of the @code{rsync} process.
  13550. @item @code{uid} (default: @var{"rsyncd"})
  13551. User name or user ID that file transfers to and from that module should take
  13552. place as when the daemon was run as @code{root}.
  13553. @item @code{gid} (default: @var{"rsyncd"})
  13554. Group name or group ID that will be used when accessing the module.
  13555. @end table
  13556. @end deftp
  13557. The @code{(gnu services syncthing)} module provides the following services:
  13558. @cindex syncthing
  13559. You might want a syncthing daemon if you have files between two or more
  13560. computers and want to sync them in real time, safely protected from
  13561. prying eyes.
  13562. @deffn {Scheme Variable} syncthing-service-type
  13563. This is the service type for the @uref{https://syncthing.net/,
  13564. syncthing} daemon, The value for this service type is a
  13565. @command{syncthing-configuration} record as in this example:
  13566. @lisp
  13567. (service syncthing-service-type
  13568. (syncthing-configuration (user "alice")))
  13569. @end lisp
  13570. See below for details about @code{syncthing-configuration}.
  13571. @deftp {Data Type} syncthing-configuration
  13572. Data type representing the configuration for @code{syncthing-service-type}.
  13573. @table @asis
  13574. @item @code{syncthing} (default: @var{syncthing})
  13575. @code{syncthing} package to use.
  13576. @item @code{arguments} (default: @var{'()})
  13577. List of command-line arguments passing to @code{syncthing} binary.
  13578. @item @code{logflags} (default: @var{0})
  13579. Sum of loging flags, see
  13580. @uref{https://docs.syncthing.net/users/syncthing.html#cmdoption-logflags, Syncthing documentation logflags}.
  13581. @item @code{user} (default: @var{#f})
  13582. The user as which the Syncthing service is to be run.
  13583. This assumes that the specified user exists.
  13584. @item @code{group} (default: @var{"users"})
  13585. The group as which the Syncthing service is to be run.
  13586. This assumes that the specified group exists.
  13587. @item @code{home} (default: @var{#f})
  13588. Common configuration and data directory. The default configuration
  13589. directory is @file{$HOME} of the specified Syncthing @code{user}.
  13590. @end table
  13591. @end deftp
  13592. @end deffn
  13593. Furthermore, @code{(gnu services ssh)} provides the following services.
  13594. @cindex SSH
  13595. @cindex SSH server
  13596. @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
  13597. [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
  13598. [#:allow-empty-passwords? #f] [#:root-login? #f] @
  13599. [#:syslog-output? #t] [#:x11-forwarding? #t] @
  13600. [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
  13601. [#:public-key-authentication? #t] [#:initialize? #t]
  13602. Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
  13603. @var{host-key} must designate a file containing the host key, and readable
  13604. only by root.
  13605. When @var{daemonic?} is true, @command{lshd} will detach from the
  13606. controlling terminal and log its output to syslogd, unless one sets
  13607. @var{syslog-output?} to false. Obviously, it also makes lsh-service
  13608. depend on existence of syslogd service. When @var{pid-file?} is true,
  13609. @command{lshd} writes its PID to the file called @var{pid-file}.
  13610. When @var{initialize?} is true, automatically create the seed and host key
  13611. upon service activation if they do not exist yet. This may take long and
  13612. require interaction.
  13613. When @var{initialize?} is false, it is up to the user to initialize the
  13614. randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
  13615. a key pair with the private key stored in file @var{host-key} (@pxref{lshd
  13616. basics,,, lsh, LSH Manual}).
  13617. When @var{interfaces} is empty, lshd listens for connections on all the
  13618. network interfaces; otherwise, @var{interfaces} must be a list of host names
  13619. or addresses.
  13620. @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
  13621. passwords, and @var{root-login?} specifies whether to accept log-ins as
  13622. root.
  13623. The other options should be self-descriptive.
  13624. @end deffn
  13625. @cindex SSH
  13626. @cindex SSH server
  13627. @deffn {Scheme Variable} openssh-service-type
  13628. This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
  13629. shell daemon, @command{sshd}. Its value must be an
  13630. @code{openssh-configuration} record as in this example:
  13631. @lisp
  13632. (service openssh-service-type
  13633. (openssh-configuration
  13634. (x11-forwarding? #t)
  13635. (permit-root-login 'without-password)
  13636. (authorized-keys
  13637. `(("alice" ,(local-file "alice.pub"))
  13638. ("bob" ,(local-file "bob.pub"))))))
  13639. @end lisp
  13640. See below for details about @code{openssh-configuration}.
  13641. This service can be extended with extra authorized keys, as in this
  13642. example:
  13643. @lisp
  13644. (service-extension openssh-service-type
  13645. (const `(("charlie"
  13646. ,(local-file "charlie.pub")))))
  13647. @end lisp
  13648. @end deffn
  13649. @deftp {Data Type} openssh-configuration
  13650. This is the configuration record for OpenSSH's @command{sshd}.
  13651. @table @asis
  13652. @item @code{openssh} (default @var{openssh})
  13653. The Openssh package to use.
  13654. @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
  13655. Name of the file where @command{sshd} writes its PID.
  13656. @item @code{port-number} (default: @code{22})
  13657. TCP port on which @command{sshd} listens for incoming connections.
  13658. @item @code{permit-root-login} (default: @code{#f})
  13659. This field determines whether and when to allow logins as root. If
  13660. @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
  13661. If it's the symbol @code{'without-password}, then root logins are
  13662. permitted but not with password-based authentication.
  13663. @item @code{allow-empty-passwords?} (default: @code{#f})
  13664. When true, users with empty passwords may log in. When false, they may
  13665. not.
  13666. @item @code{password-authentication?} (default: @code{#t})
  13667. When true, users may log in with their password. When false, they have
  13668. other authentication methods.
  13669. @item @code{public-key-authentication?} (default: @code{#t})
  13670. When true, users may log in using public key authentication. When
  13671. false, users have to use other authentication method.
  13672. Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
  13673. This is used only by protocol version 2.
  13674. @item @code{x11-forwarding?} (default: @code{#f})
  13675. When true, forwarding of X11 graphical client connections is
  13676. enabled---in other words, @command{ssh} options @option{-X} and
  13677. @option{-Y} will work.
  13678. @item @code{allow-agent-forwarding?} (default: @code{#t})
  13679. Whether to allow agent forwarding.
  13680. @item @code{allow-tcp-forwarding?} (default: @code{#t})
  13681. Whether to allow TCP forwarding.
  13682. @item @code{gateway-ports?} (default: @code{#f})
  13683. Whether to allow gateway ports.
  13684. @item @code{challenge-response-authentication?} (default: @code{#f})
  13685. Specifies whether challenge response authentication is allowed (e.g.@: via
  13686. PAM).
  13687. @item @code{use-pam?} (default: @code{#t})
  13688. Enables the Pluggable Authentication Module interface. If set to
  13689. @code{#t}, this will enable PAM authentication using
  13690. @code{challenge-response-authentication?} and
  13691. @code{password-authentication?}, in addition to PAM account and session
  13692. module processing for all authentication types.
  13693. Because PAM challenge response authentication usually serves an
  13694. equivalent role to password authentication, you should disable either
  13695. @code{challenge-response-authentication?} or
  13696. @code{password-authentication?}.
  13697. @item @code{print-last-log?} (default: @code{#t})
  13698. Specifies whether @command{sshd} should print the date and time of the
  13699. last user login when a user logs in interactively.
  13700. @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
  13701. Configures external subsystems (e.g.@: file transfer daemon).
  13702. This is a list of two-element lists, each of which containing the
  13703. subsystem name and a command (with optional arguments) to execute upon
  13704. subsystem request.
  13705. The command @command{internal-sftp} implements an in-process SFTP
  13706. server. Alternatively, one can specify the @command{sftp-server} command:
  13707. @lisp
  13708. (service openssh-service-type
  13709. (openssh-configuration
  13710. (subsystems
  13711. `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
  13712. @end lisp
  13713. @item @code{accepted-environment} (default: @code{'()})
  13714. List of strings describing which environment variables may be exported.
  13715. Each string gets on its own line. See the @code{AcceptEnv} option in
  13716. @code{man sshd_config}.
  13717. This example allows ssh-clients to export the @env{COLORTERM} variable.
  13718. It is set by terminal emulators, which support colors. You can use it in
  13719. your shell's resource file to enable colors for the prompt and commands
  13720. if this variable is set.
  13721. @lisp
  13722. (service openssh-service-type
  13723. (openssh-configuration
  13724. (accepted-environment '("COLORTERM"))))
  13725. @end lisp
  13726. @item @code{authorized-keys} (default: @code{'()})
  13727. @cindex authorized keys, SSH
  13728. @cindex SSH authorized keys
  13729. This is the list of authorized keys. Each element of the list is a user
  13730. name followed by one or more file-like objects that represent SSH public
  13731. keys. For example:
  13732. @lisp
  13733. (openssh-configuration
  13734. (authorized-keys
  13735. `(("rekado" ,(local-file "rekado.pub"))
  13736. ("chris" ,(local-file "chris.pub"))
  13737. ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
  13738. @end lisp
  13739. @noindent
  13740. registers the specified public keys for user accounts @code{rekado},
  13741. @code{chris}, and @code{root}.
  13742. Additional authorized keys can be specified @i{via}
  13743. @code{service-extension}.
  13744. Note that this does @emph{not} interfere with the use of
  13745. @file{~/.ssh/authorized_keys}.
  13746. @item @code{log-level} (default: @code{'info})
  13747. This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
  13748. @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
  13749. page for @file{sshd_config} for the full list of level names.
  13750. @item @code{extra-content} (default: @code{""})
  13751. This field can be used to append arbitrary text to the configuration file. It
  13752. is especially useful for elaborate configurations that cannot be expressed
  13753. otherwise. This configuration, for example, would generally disable root
  13754. logins, but permit them from one specific IP address:
  13755. @lisp
  13756. (openssh-configuration
  13757. (extra-content "\
  13758. Match Address 192.168.0.1
  13759. PermitRootLogin yes"))
  13760. @end lisp
  13761. @end table
  13762. @end deftp
  13763. @deffn {Scheme Procedure} dropbear-service [@var{config}]
  13764. Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
  13765. daemon} with the given @var{config}, a @code{<dropbear-configuration>}
  13766. object.
  13767. For example, to specify a Dropbear service listening on port 1234, add
  13768. this call to the operating system's @code{services} field:
  13769. @lisp
  13770. (dropbear-service (dropbear-configuration
  13771. (port-number 1234)))
  13772. @end lisp
  13773. @end deffn
  13774. @deftp {Data Type} dropbear-configuration
  13775. This data type represents the configuration of a Dropbear SSH daemon.
  13776. @table @asis
  13777. @item @code{dropbear} (default: @var{dropbear})
  13778. The Dropbear package to use.
  13779. @item @code{port-number} (default: 22)
  13780. The TCP port where the daemon waits for incoming connections.
  13781. @item @code{syslog-output?} (default: @code{#t})
  13782. Whether to enable syslog output.
  13783. @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
  13784. File name of the daemon's PID file.
  13785. @item @code{root-login?} (default: @code{#f})
  13786. Whether to allow @code{root} logins.
  13787. @item @code{allow-empty-passwords?} (default: @code{#f})
  13788. Whether to allow empty passwords.
  13789. @item @code{password-authentication?} (default: @code{#t})
  13790. Whether to enable password-based authentication.
  13791. @end table
  13792. @end deftp
  13793. @cindex AutoSSH
  13794. @deffn {Scheme Variable} autossh-service-type
  13795. This is the type for the @uref{https://www.harding.motd.ca/autossh,
  13796. AutoSSH} program that runs a copy of @command{ssh} and monitors it,
  13797. restarting it as necessary should it die or stop passing traffic.
  13798. AutoSSH can be run manually from the command-line by passing arguments
  13799. to the binary @command{autossh} from the package @code{autossh}, but it
  13800. can also be run as a Guix service. This latter use case is documented
  13801. here.
  13802. AutoSSH can be used to forward local traffic to a remote machine using
  13803. an SSH tunnel, and it respects the @file{~/.ssh/config} of the user it
  13804. is run as.
  13805. For example, to specify a service running autossh as the user
  13806. @code{pino} and forwarding all local connections to port @code{8081} to
  13807. @code{remote:8081} using an SSH tunnel, add this call to the operating
  13808. system's @code{services} field:
  13809. @lisp
  13810. (service autossh-service-type
  13811. (autossh-configuration
  13812. (user "pino")
  13813. (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
  13814. @end lisp
  13815. @end deffn
  13816. @deftp {Data Type} autossh-configuration
  13817. This data type represents the configuration of an AutoSSH service.
  13818. @table @asis
  13819. @item @code{user} (default @code{"autossh"})
  13820. The user as which the AutoSSH service is to be run.
  13821. This assumes that the specified user exists.
  13822. @item @code{poll} (default @code{600})
  13823. Specifies the connection poll time in seconds.
  13824. @item @code{first-poll} (default @code{#f})
  13825. Specifies how many seconds AutoSSH waits before the first connection
  13826. test. After this first test, polling is resumed at the pace defined in
  13827. @code{poll}. When set to @code{#f}, the first poll is not treated
  13828. specially and will also use the connection poll specified in
  13829. @code{poll}.
  13830. @item @code{gate-time} (default @code{30})
  13831. Specifies how many seconds an SSH connection must be active before it is
  13832. considered successful.
  13833. @item @code{log-level} (default @code{1})
  13834. The log level, corresponding to the levels used by syslog---so @code{0}
  13835. is the most silent while @code{7} is the chattiest.
  13836. @item @code{max-start} (default @code{#f})
  13837. The maximum number of times SSH may be (re)started before AutoSSH exits.
  13838. When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
  13839. @item @code{message} (default @code{""})
  13840. The message to append to the echo message sent when testing connections.
  13841. @item @code{port} (default @code{"0"})
  13842. The ports used for monitoring the connection. When set to @code{"0"},
  13843. monitoring is disabled. When set to @code{"@var{n}"} where @var{n} is
  13844. a positive integer, ports @var{n} and @var{n}+1 are used for
  13845. monitoring the connection, such that port @var{n} is the base
  13846. monitoring port and @code{n+1} is the echo port. When set to
  13847. @code{"@var{n}:@var{m}"} where @var{n} and @var{m} are positive
  13848. integers, the ports @var{n} and @var{m} are used for monitoring the
  13849. connection, such that port @var{n} is the base monitoring port and
  13850. @var{m} is the echo port.
  13851. @item @code{ssh-options} (default @code{'()})
  13852. The list of command-line arguments to pass to @command{ssh} when it is
  13853. run. Options @option{-f} and @option{-M} are reserved for AutoSSH and
  13854. may cause undefined behaviour.
  13855. @end table
  13856. @end deftp
  13857. @cindex WebSSH
  13858. @deffn {Scheme Variable} webssh-service-type
  13859. This is the type for the @uref{https://webssh.huashengdun.org/, WebSSH}
  13860. program that runs a web SSH client. WebSSH can be run manually from the
  13861. command-line by passing arguments to the binary @command{wssh} from the
  13862. package @code{webssh}, but it can also be run as a Guix service. This
  13863. latter use case is documented here.
  13864. For example, to specify a service running WebSSH on loopback interface
  13865. on port @code{8888} with reject policy with a list of allowed to
  13866. connection hosts, and NGINX as a reverse-proxy to this service listening
  13867. for HTTPS connection, add this call to the operating system's
  13868. @code{services} field:
  13869. @lisp
  13870. (service webssh-service-type
  13871. (webssh-configuration (address "127.0.0.1")
  13872. (port 8888)
  13873. (policy 'reject)
  13874. (known-hosts '("localhost ecdsa-sha2-nistp256 AAAA…"
  13875. "127.0.0.1 ecdsa-sha2-nistp256 AAAA…"))))
  13876. (service nginx-service-type
  13877. (nginx-configuration
  13878. (server-blocks
  13879. (list
  13880. (nginx-server-configuration
  13881. (inherit %webssh-configuration-nginx)
  13882. (server-name '("webssh.example.com"))
  13883. (listen '("443 ssl"))
  13884. (ssl-certificate (letsencrypt-certificate "webssh.example.com"))
  13885. (ssl-certificate-key (letsencrypt-key "webssh.example.com"))
  13886. (locations
  13887. (cons (nginx-location-configuration
  13888. (uri "/.well-known")
  13889. (body '("root /var/www;")))
  13890. (nginx-server-configuration-locations %webssh-configuration-nginx))))))))
  13891. @end lisp
  13892. @end deffn
  13893. @deftp {Data Type} webssh-configuration
  13894. Data type representing the configuration for @code{webssh-service}.
  13895. @table @asis
  13896. @item @code{package} (default: @var{webssh})
  13897. @code{webssh} package to use.
  13898. @item @code{user-name} (default: @var{"webssh"})
  13899. User name or user ID that file transfers to and from that module should take
  13900. place.
  13901. @item @code{group-name} (default: @var{"webssh"})
  13902. Group name or group ID that will be used when accessing the module.
  13903. @item @code{address} (default: @var{#f})
  13904. IP address on which @command{webssh} listens for incoming connections.
  13905. @item @code{port} (default: @var{8888})
  13906. TCP port on which @command{webssh} listens for incoming connections.
  13907. @item @code{policy} (default: @var{#f})
  13908. Connection policy. @var{reject} policy requires to specify @var{known-hosts}.
  13909. @item @code{known-hosts} (default: @var{'()})
  13910. List of hosts which allowed for SSH connection from @command{webssh}.
  13911. @item @code{log-file} (default: @file{"/var/log/webssh.log"})
  13912. Name of the file where @command{webssh} writes its log file.
  13913. @item @code{log-level} (default: @var{#f})
  13914. Logging level.
  13915. @end table
  13916. @end deftp
  13917. @defvr {Scheme Variable} %facebook-host-aliases
  13918. This variable contains a string for use in @file{/etc/hosts}
  13919. (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
  13920. line contains a entry that maps a known server name of the Facebook
  13921. on-line service---e.g., @code{www.facebook.com}---to the local
  13922. host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
  13923. This variable is typically used in the @code{hosts-file} field of an
  13924. @code{operating-system} declaration (@pxref{operating-system Reference,
  13925. @file{/etc/hosts}}):
  13926. @lisp
  13927. (use-modules (gnu) (guix))
  13928. (operating-system
  13929. (host-name "mymachine")
  13930. ;; ...
  13931. (hosts-file
  13932. ;; Create a /etc/hosts file with aliases for "localhost"
  13933. ;; and "mymachine", as well as for Facebook servers.
  13934. (plain-file "hosts"
  13935. (string-append (local-host-aliases host-name)
  13936. %facebook-host-aliases))))
  13937. @end lisp
  13938. This mechanism can prevent programs running locally, such as Web
  13939. browsers, from accessing Facebook.
  13940. @end defvr
  13941. The @code{(gnu services avahi)} provides the following definition.
  13942. @defvr {Scheme Variable} avahi-service-type
  13943. This is the service that runs @command{avahi-daemon}, a system-wide
  13944. mDNS/DNS-SD responder that allows for service discovery and
  13945. ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
  13946. Its value must be an @code{avahi-configuration} record---see below.
  13947. This service extends the name service cache daemon (nscd) so that it can
  13948. resolve @code{.local} host names using
  13949. @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
  13950. Service Switch}, for information on host name resolution.
  13951. Additionally, add the @var{avahi} package to the system profile so that
  13952. commands such as @command{avahi-browse} are directly usable.
  13953. @end defvr
  13954. @deftp {Data Type} avahi-configuration
  13955. Data type representation the configuration for Avahi.
  13956. @table @asis
  13957. @item @code{host-name} (default: @code{#f})
  13958. If different from @code{#f}, use that as the host name to
  13959. publish for this machine; otherwise, use the machine's actual host name.
  13960. @item @code{publish?} (default: @code{#t})
  13961. When true, allow host names and services to be published (broadcast) over the
  13962. network.
  13963. @item @code{publish-workstation?} (default: @code{#t})
  13964. When true, @command{avahi-daemon} publishes the machine's host name and IP
  13965. address via mDNS on the local network. To view the host names published on
  13966. your local network, you can run:
  13967. @example
  13968. avahi-browse _workstation._tcp
  13969. @end example
  13970. @item @code{wide-area?} (default: @code{#f})
  13971. When true, DNS-SD over unicast DNS is enabled.
  13972. @item @code{ipv4?} (default: @code{#t})
  13973. @itemx @code{ipv6?} (default: @code{#t})
  13974. These fields determine whether to use IPv4/IPv6 sockets.
  13975. @item @code{domains-to-browse} (default: @code{'()})
  13976. This is a list of domains to browse.
  13977. @end table
  13978. @end deftp
  13979. @deffn {Scheme Variable} openvswitch-service-type
  13980. This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
  13981. service, whose value should be an @code{openvswitch-configuration}
  13982. object.
  13983. @end deffn
  13984. @deftp {Data Type} openvswitch-configuration
  13985. Data type representing the configuration of Open vSwitch, a multilayer
  13986. virtual switch which is designed to enable massive network automation
  13987. through programmatic extension.
  13988. @table @asis
  13989. @item @code{package} (default: @var{openvswitch})
  13990. Package object of the Open vSwitch.
  13991. @end table
  13992. @end deftp
  13993. @defvr {Scheme Variable} pagekite-service-type
  13994. This is the service type for the @uref{https://pagekite.net, PageKite} service,
  13995. a tunneling solution for making localhost servers publicly visible, even from
  13996. behind restrictive firewalls or NAT without forwarded ports. The value for
  13997. this service type is a @code{pagekite-configuration} record.
  13998. Here's an example exposing the local HTTP and SSH daemons:
  13999. @lisp
  14000. (service pagekite-service-type
  14001. (pagekite-configuration
  14002. (kites '("http:@@kitename:localhost:80:@@kitesecret"
  14003. "raw/22:@@kitename:localhost:22:@@kitesecret"))
  14004. (extra-file "/etc/pagekite.rc")))
  14005. @end lisp
  14006. @end defvr
  14007. @deftp {Data Type} pagekite-configuration
  14008. Data type representing the configuration of PageKite.
  14009. @table @asis
  14010. @item @code{package} (default: @var{pagekite})
  14011. Package object of PageKite.
  14012. @item @code{kitename} (default: @code{#f})
  14013. PageKite name for authenticating to the frontend server.
  14014. @item @code{kitesecret} (default: @code{#f})
  14015. Shared secret for authenticating to the frontend server. You should probably
  14016. put this inside @code{extra-file} instead.
  14017. @item @code{frontend} (default: @code{#f})
  14018. Connect to the named PageKite frontend server instead of the
  14019. @uref{https://pagekite.net,,pagekite.net} service.
  14020. @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
  14021. List of service kites to use. Exposes HTTP on port 80 by default. The format
  14022. is @code{proto:kitename:host:port:secret}.
  14023. @item @code{extra-file} (default: @code{#f})
  14024. Extra configuration file to read, which you are expected to create manually.
  14025. Use this to add additional options and manage shared secrets out-of-band.
  14026. @end table
  14027. @end deftp
  14028. @defvr {Scheme Variable} yggdrasil-service-type
  14029. The service type for connecting to the @uref{https://yggdrasil-network.github.io/,
  14030. Yggdrasil network}, an early-stage implementation of a fully end-to-end
  14031. encrypted IPv6 network.
  14032. @quotation
  14033. Yggdrasil provides name-independent routing with cryptographically generated
  14034. addresses. Static addressing means you can keep the same address as long as
  14035. you want, even if you move to a new location, or generate a new address (by
  14036. generating new keys) whenever you want.
  14037. @uref{https://yggdrasil-network.github.io/2018/07/28/addressing.html}
  14038. @end quotation
  14039. Pass it a value of @code{yggdrasil-configuration} to connect it to public
  14040. peers and/or local peers.
  14041. Here is an example using public peers and a static address. The static
  14042. signing and encryption keys are defined in @file{/etc/yggdrasil-private.conf}
  14043. (the default value for @code{config-file}).
  14044. @lisp
  14045. ;; part of the operating-system declaration
  14046. (service yggdrasil-service-type
  14047. (yggdrasil-configuration
  14048. (autoconf? #f) ;; use only the public peers
  14049. (json-config
  14050. ;; choose one from
  14051. ;; https://github.com/yggdrasil-network/public-peers
  14052. '((peers . #("tcp://1.2.3.4:1337"))))
  14053. ;; /etc/yggdrasil-private.conf is the default value for config-file
  14054. ))
  14055. @end lisp
  14056. @example
  14057. # sample content for /etc/yggdrasil-private.conf
  14058. @{
  14059. # Your public encryption key. Your peers may ask you for this to put
  14060. # into their AllowedEncryptionPublicKeys configuration.
  14061. EncryptionPublicKey: 378dc5...
  14062. # Your private encryption key. DO NOT share this with anyone!
  14063. EncryptionPrivateKey: 0777...
  14064. # Your public signing key. You should not ordinarily need to share
  14065. # this with anyone.
  14066. SigningPublicKey: e1664...
  14067. # Your private signing key. DO NOT share this with anyone!
  14068. SigningPrivateKey: 0589d...
  14069. @}
  14070. @end example
  14071. @end defvr
  14072. @deftp {Data Type} yggdrasil-configuration
  14073. Data type representing the configuration of Yggdrasil.
  14074. @table @asis
  14075. @item @code{package} (default: @code{yggdrasil})
  14076. Package object of Yggdrasil.
  14077. @item @code{json-config} (default: @code{'()})
  14078. Contents of @file{/etc/yggdrasil.conf}. Will be merged with
  14079. @file{/etc/yggdrasil-private.conf}. Note that these settings are stored in
  14080. the Guix store, which is readable to all users. @strong{Do not store your
  14081. private keys in it}. See the output of @code{yggdrasil -genconf} for a
  14082. quick overview of valid keys and their default values.
  14083. @item @code{autoconf?} (default: @code{#f})
  14084. Whether to use automatic mode. Enabling it makes Yggdrasil use adynamic IP
  14085. and peer with IPv6 neighbors.
  14086. @item @code{log-level} (default: @code{'info})
  14087. How much detail to include in logs. Use @code{'debug} for more detail.
  14088. @item @code{log-to} (default: @code{'stdout})
  14089. Where to send logs. By default, the service logs standard output to
  14090. @file{/var/log/yggdrasil.log}. The alternative is @code{'syslog}, which
  14091. sends output to the running syslog service.
  14092. @item @code{config-file} (default: @code{"/etc/yggdrasil-private.conf"})
  14093. What HJSON file to load sensitive data from. This is where private keys
  14094. should be stored, which are necessary to specify if you don't want a
  14095. randomized address after each restart. Use @code{#f} to disable. Options
  14096. defined in this file take precedence over @code{json-config}. Use the output
  14097. of @code{yggdrasil -genconf} as a starting point. To configure a static
  14098. address, delete everything except these options:
  14099. @itemize
  14100. @item @code{EncryptionPublicKey}
  14101. @item @code{EncryptionPrivateKey}
  14102. @item @code{SigningPublicKey}
  14103. @item @code{SigningPrivateKey}
  14104. @end itemize
  14105. @end table
  14106. @end deftp
  14107. @cindex keepalived
  14108. @deffn {Scheme Variable} keepalived-service-type
  14109. This is the type for the @uref{https://www.keepalived.org/, Keepalived}
  14110. routing software, @command{keepalived}. Its value must be an
  14111. @code{keepalived-configuration} record as in this example for master
  14112. machine:
  14113. @lisp
  14114. (service keepalived-service-type
  14115. (keepalived-configuration
  14116. (config-file (local-file "keepalived-master.conf"))))
  14117. @end lisp
  14118. where @file{keepalived-master.conf}:
  14119. @example
  14120. vrrp_instance my-group @{
  14121. state MASTER
  14122. interface enp9s0
  14123. virtual_router_id 100
  14124. priority 100
  14125. unicast_peer @{ 10.0.0.2 @}
  14126. virtual_ipaddress @{
  14127. 10.0.0.4/24
  14128. @}
  14129. @}
  14130. @end example
  14131. and for backup machine:
  14132. @lisp
  14133. (service keepalived-service-type
  14134. (keepalived-configuration
  14135. (config-file (local-file "keepalived-backup.conf"))))
  14136. @end lisp
  14137. where @file{keepalived-backup.conf}:
  14138. @example
  14139. vrrp_instance my-group @{
  14140. state BACKUP
  14141. interface enp9s0
  14142. virtual_router_id 100
  14143. priority 99
  14144. unicast_peer @{ 10.0.0.3 @}
  14145. virtual_ipaddress @{
  14146. 10.0.0.4/24
  14147. @}
  14148. @}
  14149. @end example
  14150. @end deffn
  14151. @node Unattended Upgrades
  14152. @subsection Unattended Upgrades
  14153. @cindex unattended upgrades
  14154. @cindex upgrades, unattended
  14155. Guix provides a service to perform @emph{unattended upgrades}:
  14156. periodically, the system automatically reconfigures itself from the
  14157. latest Guix. Guix System has several properties that make unattended
  14158. upgrades safe:
  14159. @itemize
  14160. @item
  14161. upgrades are transactional (either the upgrade succeeds or it fails, but
  14162. you cannot end up with an ``in-between'' system state);
  14163. @item
  14164. the upgrade log is kept---you can view it with @command{guix system
  14165. list-generations}---and you can roll back to any previous generation,
  14166. should the upgraded system fail to behave as intended;
  14167. @item
  14168. channel code is authenticated so you know you can only run genuine code
  14169. (@pxref{Channels});
  14170. @item
  14171. @command{guix system reconfigure} prevents downgrades, which makes it
  14172. immune to @dfn{downgrade attacks}.
  14173. @end itemize
  14174. To set up unattended upgrades, add an instance of
  14175. @code{unattended-upgrade-service-type} like the one below to the list of
  14176. your operating system services:
  14177. @lisp
  14178. (service unattended-upgrade-service-type)
  14179. @end lisp
  14180. The defaults above set up weekly upgrades: every Sunday at midnight.
  14181. You do not need to provide the operating system configuration file: it
  14182. uses @file{/run/current-system/configuration.scm}, which ensures it
  14183. always uses your latest configuration---@pxref{provenance-service-type},
  14184. for more information about this file.
  14185. There are several things that can be configured, in particular the
  14186. periodicity and services (daemons) to be restarted upon completion.
  14187. When the upgrade is successful, the service takes care of deleting
  14188. system generations older that some threshold, as per @command{guix
  14189. system delete-generations}. See the reference below for details.
  14190. To ensure that upgrades are actually happening, you can run
  14191. @command{guix system describe}. To investigate upgrade failures, visit
  14192. the unattended upgrade log file (see below).
  14193. @defvr {Scheme Variable} unattended-upgrade-service-type
  14194. This is the service type for unattended upgrades. It sets up an mcron
  14195. job (@pxref{Scheduled Job Execution}) that runs @command{guix system
  14196. reconfigure} from the latest version of the specified channels.
  14197. Its value must be a @code{unattended-upgrade-configuration} record (see
  14198. below).
  14199. @end defvr
  14200. @deftp {Data Type} unattended-upgrade-configuration
  14201. This data type represents the configuration of the unattended upgrade
  14202. service. The following fields are available:
  14203. @table @asis
  14204. @item @code{schedule} (default: @code{"30 01 * * 0"})
  14205. This is the schedule of upgrades, expressed as a gexp containing an
  14206. mcron job schedule (@pxref{Guile Syntax, mcron job specifications,,
  14207. mcron, GNU@tie{}mcron}).
  14208. @item @code{channels} (default: @code{#~%default-channels})
  14209. This gexp specifies the channels to use for the upgrade
  14210. (@pxref{Channels}). By default, the tip of the official @code{guix}
  14211. channel is used.
  14212. @item @code{operating-system-file} (default: @code{"/run/current-system/configuration.scm"})
  14213. This field specifies the operating system configuration file to use.
  14214. The default is to reuse the config file of the current configuration.
  14215. There are cases, though, where referring to
  14216. @file{/run/current-system/configuration.scm} is not enough, for instance
  14217. because that file refers to extra files (SSH public keys, extra
  14218. configuration files, etc.) @i{via} @code{local-file} and similar
  14219. constructs. For those cases, we recommend something along these lines:
  14220. @lisp
  14221. (unattended-upgrade-configuration
  14222. (operating-system-file
  14223. (file-append (local-file "." "config-dir" #:recursive? #t)
  14224. "/config.scm")))
  14225. @end lisp
  14226. The effect here is to import all of the current directory into the
  14227. store, and to refer to @file{config.scm} within that directory.
  14228. Therefore, uses of @code{local-file} within @file{config.scm} will work
  14229. as expected. @xref{G-Expressions}, for information about
  14230. @code{local-file} and @code{file-append}.
  14231. @item @code{services-to-restart} (default: @code{'(mcron)})
  14232. This field specifies the Shepherd services to restart when the upgrade
  14233. completes.
  14234. Those services are restarted right away upon completion, as with
  14235. @command{herd restart}, which ensures that the latest version is
  14236. running---remember that by default @command{guix system reconfigure}
  14237. only restarts services that are not currently running, which is
  14238. conservative: it minimizes disruption but leaves outdated services
  14239. running.
  14240. Use @command{herd status} to find out candidates for restarting.
  14241. @xref{Services}, for general information about services. Common
  14242. services to restart would include @code{ntpd} and @code{ssh-daemon}.
  14243. By default, the @code{mcron} service is restarted. This ensures that
  14244. the latest version of the unattended upgrade job will be used next time.
  14245. @item @code{system-expiration} (default: @code{(* 3 30 24 3600)})
  14246. This is the expiration time in seconds for system generations. System
  14247. generations older that this amount of time are deleted with
  14248. @command{guix system delete-generations} when an upgrade completes.
  14249. @quotation Note
  14250. The unattended upgrade service does not run the garbage collector. You
  14251. will probably want to set up your own mcron job to run @command{guix gc}
  14252. periodically.
  14253. @end quotation
  14254. @item @code{maximum-duration} (default: @code{3600})
  14255. Maximum duration in seconds for the upgrade; past that time, the upgrade
  14256. aborts.
  14257. This is primarily useful to ensure the upgrade does not end up
  14258. rebuilding or re-downloading ``the world''.
  14259. @item @code{log-file} (default: @code{"/var/log/unattended-upgrade.log"})
  14260. File where unattended upgrades are logged.
  14261. @end table
  14262. @end deftp
  14263. @node X Window
  14264. @subsection X Window
  14265. @cindex X11
  14266. @cindex X Window System
  14267. @cindex login manager
  14268. Support for the X Window graphical display system---specifically
  14269. Xorg---is provided by the @code{(gnu services xorg)} module. Note that
  14270. there is no @code{xorg-service} procedure. Instead, the X server is
  14271. started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
  14272. @cindex GDM
  14273. @cindex GNOME, login manager
  14274. GDM of course allows users to log in into window managers and desktop
  14275. environments other than GNOME; for those using GNOME, GDM is required for
  14276. features such as automatic screen locking.
  14277. @cindex window manager
  14278. To use X11, you must install at least one @dfn{window manager}---for
  14279. example the @code{windowmaker} or @code{openbox} packages---preferably
  14280. by adding it to the @code{packages} field of your operating system
  14281. definition (@pxref{operating-system Reference, system-wide packages}).
  14282. @defvr {Scheme Variable} gdm-service-type
  14283. This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
  14284. Desktop Manager} (GDM), a program that manages graphical display servers and
  14285. handles graphical user logins. Its value must be a @code{gdm-configuration}
  14286. (see below).
  14287. @cindex session types (X11)
  14288. @cindex X11 session types
  14289. GDM looks for @dfn{session types} described by the @file{.desktop} files in
  14290. @file{/run/current-system/profile/share/xsessions} and allows users to choose
  14291. a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
  14292. and @code{i3} provide @file{.desktop} files; adding them to the system-wide
  14293. set of packages automatically makes them available at the log-in screen.
  14294. In addition, @file{~/.xsession} files are honored. When available,
  14295. @file{~/.xsession} must be an executable that starts a window manager
  14296. and/or other X clients.
  14297. @end defvr
  14298. @deftp {Data Type} gdm-configuration
  14299. @table @asis
  14300. @item @code{auto-login?} (default: @code{#f})
  14301. @itemx @code{default-user} (default: @code{#f})
  14302. When @code{auto-login?} is false, GDM presents a log-in screen.
  14303. When @code{auto-login?} is true, GDM logs in directly as
  14304. @code{default-user}.
  14305. @item @code{debug?} (default: @code{#f})
  14306. When true, GDM writes debug messages to its log.
  14307. @item @code{gnome-shell-assets} (default: ...)
  14308. List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
  14309. @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
  14310. Configuration of the Xorg graphical server.
  14311. @item @code{xsession} (default: @code{(xinitrc)})
  14312. Script to run before starting a X session.
  14313. @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
  14314. File name of the @code{dbus-daemon} executable.
  14315. @item @code{gdm} (default: @code{gdm})
  14316. The GDM package to use.
  14317. @end table
  14318. @end deftp
  14319. @defvr {Scheme Variable} slim-service-type
  14320. This is the type for the SLiM graphical login manager for X11.
  14321. Like GDM, SLiM looks for session types described by @file{.desktop} files and
  14322. allows users to choose a session from the log-in screen using @kbd{F1}. It
  14323. also honors @file{~/.xsession} files.
  14324. Unlike GDM, SLiM does not spawn the user session on a different VT after
  14325. logging in, which means that you can only start one graphical session. If you
  14326. want to be able to run multiple graphical sessions at the same time you have
  14327. to add multiple SLiM services to your system services. The following example
  14328. shows how to replace the default GDM service with two SLiM services on tty7
  14329. and tty8.
  14330. @lisp
  14331. (use-modules (gnu services)
  14332. (gnu services desktop)
  14333. (gnu services xorg)
  14334. (srfi srfi-1)) ;for 'remove'
  14335. (operating-system
  14336. ;; ...
  14337. (services (cons* (service slim-service-type (slim-configuration
  14338. (display ":0")
  14339. (vt "vt7")))
  14340. (service slim-service-type (slim-configuration
  14341. (display ":1")
  14342. (vt "vt8")))
  14343. (remove (lambda (service)
  14344. (eq? (service-kind service) gdm-service-type))
  14345. %desktop-services))))
  14346. @end lisp
  14347. @end defvr
  14348. @deftp {Data Type} slim-configuration
  14349. Data type representing the configuration of @code{slim-service-type}.
  14350. @table @asis
  14351. @item @code{allow-empty-passwords?} (default: @code{#t})
  14352. Whether to allow logins with empty passwords.
  14353. @item @code{auto-login?} (default: @code{#f})
  14354. @itemx @code{default-user} (default: @code{""})
  14355. When @code{auto-login?} is false, SLiM presents a log-in screen.
  14356. When @code{auto-login?} is true, SLiM logs in directly as
  14357. @code{default-user}.
  14358. @item @code{theme} (default: @code{%default-slim-theme})
  14359. @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
  14360. The graphical theme to use and its name.
  14361. @item @code{auto-login-session} (default: @code{#f})
  14362. If true, this must be the name of the executable to start as the default
  14363. session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
  14364. If false, a session described by one of the available @file{.desktop}
  14365. files in @code{/run/current-system/profile} and @code{~/.guix-profile}
  14366. will be used.
  14367. @quotation Note
  14368. You must install at least one window manager in the system profile or in
  14369. your user profile. Failing to do that, if @code{auto-login-session} is
  14370. false, you will be unable to log in.
  14371. @end quotation
  14372. @item @code{xorg-configuration} (default @code{(xorg-configuration)})
  14373. Configuration of the Xorg graphical server.
  14374. @item @code{display} (default @code{":0"})
  14375. The display on which to start the Xorg graphical server.
  14376. @item @code{vt} (default @code{"vt7"})
  14377. The VT on which to start the Xorg graphical server.
  14378. @item @code{xauth} (default: @code{xauth})
  14379. The XAuth package to use.
  14380. @item @code{shepherd} (default: @code{shepherd})
  14381. The Shepherd package used when invoking @command{halt} and
  14382. @command{reboot}.
  14383. @item @code{sessreg} (default: @code{sessreg})
  14384. The sessreg package used in order to register the session.
  14385. @item @code{slim} (default: @code{slim})
  14386. The SLiM package to use.
  14387. @end table
  14388. @end deftp
  14389. @defvr {Scheme Variable} %default-theme
  14390. @defvrx {Scheme Variable} %default-theme-name
  14391. The default SLiM theme and its name.
  14392. @end defvr
  14393. @deftp {Data Type} sddm-configuration
  14394. This is the data type representing the SDDM service configuration.
  14395. @table @asis
  14396. @item @code{display-server} (default: "x11")
  14397. Select display server to use for the greeter. Valid values are
  14398. @samp{"x11"} or @samp{"wayland"}.
  14399. @item @code{numlock} (default: "on")
  14400. Valid values are @samp{"on"}, @samp{"off"} or @samp{"none"}.
  14401. @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
  14402. Command to run when halting.
  14403. @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
  14404. Command to run when rebooting.
  14405. @item @code{theme} (default "maldives")
  14406. Theme to use. Default themes provided by SDDM are @samp{"elarun"},
  14407. @samp{"maldives"} or @samp{"maya"}.
  14408. @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
  14409. Directory to look for themes.
  14410. @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
  14411. Directory to look for faces.
  14412. @item @code{default-path} (default "/run/current-system/profile/bin")
  14413. Default PATH to use.
  14414. @item @code{minimum-uid} (default: 1000)
  14415. Minimum UID displayed in SDDM and allowed for log-in.
  14416. @item @code{maximum-uid} (default: 2000)
  14417. Maximum UID to display in SDDM.
  14418. @item @code{remember-last-user?} (default #t)
  14419. Remember last user.
  14420. @item @code{remember-last-session?} (default #t)
  14421. Remember last session.
  14422. @item @code{hide-users} (default "")
  14423. Usernames to hide from SDDM greeter.
  14424. @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
  14425. Users with shells listed will be hidden from the SDDM greeter.
  14426. @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
  14427. Script to run before starting a wayland session.
  14428. @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
  14429. Directory to look for desktop files starting wayland sessions.
  14430. @item @code{xorg-configuration} (default @code{(xorg-configuration)})
  14431. Configuration of the Xorg graphical server.
  14432. @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
  14433. Path to xauth.
  14434. @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
  14435. Path to Xephyr.
  14436. @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
  14437. Script to run after starting xorg-server.
  14438. @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
  14439. Script to run before stopping xorg-server.
  14440. @item @code{xsession-command} (default: @code{xinitrc})
  14441. Script to run before starting a X session.
  14442. @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
  14443. Directory to look for desktop files starting X sessions.
  14444. @item @code{minimum-vt} (default: 7)
  14445. Minimum VT to use.
  14446. @item @code{auto-login-user} (default "")
  14447. User to use for auto-login.
  14448. @item @code{auto-login-session} (default "")
  14449. Desktop file to use for auto-login.
  14450. @item @code{relogin?} (default #f)
  14451. Relogin after logout.
  14452. @end table
  14453. @end deftp
  14454. @cindex login manager
  14455. @cindex X11 login
  14456. @defvr {Scheme Variable} sddm-service-type
  14457. This is the type of the service to run the
  14458. @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
  14459. must be a @code{sddm-configuration} record (see below).
  14460. Here's an example use:
  14461. @lisp
  14462. (service sddm-service-type
  14463. (sddm-configuration
  14464. (auto-login-user "alice")
  14465. (auto-login-session "xfce.desktop")))
  14466. @end lisp
  14467. @end defvr
  14468. @deftp {Data Type} sddm-configuration
  14469. This data type represents the configuration of the SDDM login manager.
  14470. The available fields are:
  14471. @table @asis
  14472. @item @code{sddm} (default: @code{sddm})
  14473. The SDDM package to use.
  14474. @item @code{display-server} (default: @code{"x11"})
  14475. This must be either @code{"x11"} or @code{"wayland"}.
  14476. @c FIXME: Add more fields.
  14477. @item @code{auto-login-user} (default: @code{""})
  14478. If non-empty, this is the user account under which to log in
  14479. automatically.
  14480. @item @code{auto-login-session} (default: @code{""})
  14481. If non-empty, this is the @file{.desktop} file name to use as the
  14482. auto-login session.
  14483. @end table
  14484. @end deftp
  14485. @cindex Xorg, configuration
  14486. @deftp {Data Type} xorg-configuration
  14487. This data type represents the configuration of the Xorg graphical display
  14488. server. Note that there is no Xorg service; instead, the X server is started
  14489. by a ``display manager'' such as GDM, SDDM, and SLiM@. Thus, the configuration
  14490. of these display managers aggregates an @code{xorg-configuration} record.
  14491. @table @asis
  14492. @item @code{modules} (default: @code{%default-xorg-modules})
  14493. This is a list of @dfn{module packages} loaded by the Xorg
  14494. server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
  14495. @item @code{fonts} (default: @code{%default-xorg-fonts})
  14496. This is a list of font directories to add to the server's @dfn{font path}.
  14497. @item @code{drivers} (default: @code{'()})
  14498. This must be either the empty list, in which case Xorg chooses a graphics
  14499. driver automatically, or a list of driver names that will be tried in this
  14500. order---e.g., @code{("modesetting" "vesa")}.
  14501. @item @code{resolutions} (default: @code{'()})
  14502. When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
  14503. resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
  14504. 768) (640 480))}.
  14505. @cindex keyboard layout, for Xorg
  14506. @cindex keymap, for Xorg
  14507. @item @code{keyboard-layout} (default: @code{#f})
  14508. If this is @code{#f}, Xorg uses the default keyboard layout---usually US
  14509. English (``qwerty'') for a 105-key PC keyboard.
  14510. Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
  14511. layout in use when Xorg is running. @xref{Keyboard Layout}, for more
  14512. information on how to specify the keyboard layout.
  14513. @item @code{extra-config} (default: @code{'()})
  14514. This is a list of strings or objects appended to the configuration file. It
  14515. is used to pass extra text to be added verbatim to the configuration file.
  14516. @item @code{server} (default: @code{xorg-server})
  14517. This is the package providing the Xorg server.
  14518. @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
  14519. This is the list of command-line arguments to pass to the X server. The
  14520. default is @code{-nolisten tcp}.
  14521. @end table
  14522. @end deftp
  14523. @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
  14524. [@var{login-manager-service-type}]
  14525. Tell the log-in manager (of type @var{login-manager-service-type}) to use
  14526. @var{config}, an @code{<xorg-configuration>} record.
  14527. Since the Xorg configuration is embedded in the log-in manager's
  14528. configuration---e.g., @code{gdm-configuration}---this procedure provides a
  14529. shorthand to set the Xorg configuration.
  14530. @end deffn
  14531. @deffn {Scheme Procedure} xorg-start-command [@var{config}]
  14532. Return a @code{startx} script in which the modules, fonts, etc. specified
  14533. in @var{config}, are available. The result should be used in place of
  14534. @code{startx}.
  14535. Usually the X server is started by a login manager.
  14536. @end deffn
  14537. @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
  14538. Add @var{package}, a package for a screen locker or screen saver whose
  14539. command is @var{program}, to the set of setuid programs and add a PAM entry
  14540. for it. For example:
  14541. @lisp
  14542. (screen-locker-service xlockmore "xlock")
  14543. @end lisp
  14544. makes the good ol' XlockMore usable.
  14545. @end deffn
  14546. @node Printing Services
  14547. @subsection Printing Services
  14548. @cindex printer support with CUPS
  14549. The @code{(gnu services cups)} module provides a Guix service definition
  14550. for the CUPS printing service. To add printer support to a Guix
  14551. system, add a @code{cups-service} to the operating system definition:
  14552. @deffn {Scheme Variable} cups-service-type
  14553. The service type for the CUPS print server. Its value should be a valid
  14554. CUPS configuration (see below). To use the default settings, simply
  14555. write:
  14556. @lisp
  14557. (service cups-service-type)
  14558. @end lisp
  14559. @end deffn
  14560. The CUPS configuration controls the basic things about your CUPS
  14561. installation: what interfaces it listens on, what to do if a print job
  14562. fails, how much logging to do, and so on. To actually add a printer,
  14563. you have to visit the @url{http://localhost:631} URL, or use a tool such
  14564. as GNOME's printer configuration services. By default, configuring a
  14565. CUPS service will generate a self-signed certificate if needed, for
  14566. secure connections to the print server.
  14567. Suppose you want to enable the Web interface of CUPS and also add
  14568. support for Epson printers @i{via} the @code{epson-inkjet-printer-escpr}
  14569. package and for HP printers @i{via} the @code{hplip-minimal} package.
  14570. You can do that directly, like this (you need to use the
  14571. @code{(gnu packages cups)} module):
  14572. @lisp
  14573. (service cups-service-type
  14574. (cups-configuration
  14575. (web-interface? #t)
  14576. (extensions
  14577. (list cups-filters epson-inkjet-printer-escpr hplip-minimal))))
  14578. @end lisp
  14579. Note: If you wish to use the Qt5 based GUI which comes with the hplip
  14580. package then it is suggested that you install the @code{hplip} package,
  14581. either in your OS configuration file or as your user.
  14582. The available configuration parameters follow. Each parameter
  14583. definition is preceded by its type; for example, @samp{string-list foo}
  14584. indicates that the @code{foo} parameter should be specified as a list of
  14585. strings. There is also a way to specify the configuration as a string,
  14586. if you have an old @code{cupsd.conf} file that you want to port over
  14587. from some other system; see the end for more details.
  14588. @c The following documentation was initially generated by
  14589. @c (generate-documentation) in (gnu services cups). Manually maintained
  14590. @c documentation is better, so we shouldn't hesitate to edit below as
  14591. @c needed. However if the change you want to make to this documentation
  14592. @c can be done in an automated way, it's probably easier to change
  14593. @c (generate-documentation) than to make it below and have to deal with
  14594. @c the churn as CUPS updates.
  14595. Available @code{cups-configuration} fields are:
  14596. @deftypevr {@code{cups-configuration} parameter} package cups
  14597. The CUPS package.
  14598. @end deftypevr
  14599. @deftypevr {@code{cups-configuration} parameter} package-list extensions (default: @code{(list brlaser cups-filters epson-inkjet-printer-escpr foomatic-filters hplip-minimal splix)})
  14600. Drivers and other extensions to the CUPS package.
  14601. @end deftypevr
  14602. @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
  14603. Configuration of where to write logs, what directories to use for print
  14604. spools, and related privileged configuration parameters.
  14605. Available @code{files-configuration} fields are:
  14606. @deftypevr {@code{files-configuration} parameter} log-location access-log
  14607. Defines the access log filename. Specifying a blank filename disables
  14608. access log generation. The value @code{stderr} causes log entries to be
  14609. sent to the standard error file when the scheduler is running in the
  14610. foreground, or to the system log daemon when run in the background. The
  14611. value @code{syslog} causes log entries to be sent to the system log
  14612. daemon. The server name may be included in filenames using the string
  14613. @code{%s}, as in @code{/var/log/cups/%s-access_log}.
  14614. Defaults to @samp{"/var/log/cups/access_log"}.
  14615. @end deftypevr
  14616. @deftypevr {@code{files-configuration} parameter} file-name cache-dir
  14617. Where CUPS should cache data.
  14618. Defaults to @samp{"/var/cache/cups"}.
  14619. @end deftypevr
  14620. @deftypevr {@code{files-configuration} parameter} string config-file-perm
  14621. Specifies the permissions for all configuration files that the scheduler
  14622. writes.
  14623. Note that the permissions for the printers.conf file are currently
  14624. masked to only allow access from the scheduler user (typically root).
  14625. This is done because printer device URIs sometimes contain sensitive
  14626. authentication information that should not be generally known on the
  14627. system. There is no way to disable this security feature.
  14628. Defaults to @samp{"0640"}.
  14629. @end deftypevr
  14630. @deftypevr {@code{files-configuration} parameter} log-location error-log
  14631. Defines the error log filename. Specifying a blank filename disables
  14632. error log generation. The value @code{stderr} causes log entries to be
  14633. sent to the standard error file when the scheduler is running in the
  14634. foreground, or to the system log daemon when run in the background. The
  14635. value @code{syslog} causes log entries to be sent to the system log
  14636. daemon. The server name may be included in filenames using the string
  14637. @code{%s}, as in @code{/var/log/cups/%s-error_log}.
  14638. Defaults to @samp{"/var/log/cups/error_log"}.
  14639. @end deftypevr
  14640. @deftypevr {@code{files-configuration} parameter} string fatal-errors
  14641. Specifies which errors are fatal, causing the scheduler to exit. The
  14642. kind strings are:
  14643. @table @code
  14644. @item none
  14645. No errors are fatal.
  14646. @item all
  14647. All of the errors below are fatal.
  14648. @item browse
  14649. Browsing initialization errors are fatal, for example failed connections
  14650. to the DNS-SD daemon.
  14651. @item config
  14652. Configuration file syntax errors are fatal.
  14653. @item listen
  14654. Listen or Port errors are fatal, except for IPv6 failures on the
  14655. loopback or @code{any} addresses.
  14656. @item log
  14657. Log file creation or write errors are fatal.
  14658. @item permissions
  14659. Bad startup file permissions are fatal, for example shared TLS
  14660. certificate and key files with world-read permissions.
  14661. @end table
  14662. Defaults to @samp{"all -browse"}.
  14663. @end deftypevr
  14664. @deftypevr {@code{files-configuration} parameter} boolean file-device?
  14665. Specifies whether the file pseudo-device can be used for new printer
  14666. queues. The URI @uref{file:///dev/null} is always allowed.
  14667. Defaults to @samp{#f}.
  14668. @end deftypevr
  14669. @deftypevr {@code{files-configuration} parameter} string group
  14670. Specifies the group name or ID that will be used when executing external
  14671. programs.
  14672. Defaults to @samp{"lp"}.
  14673. @end deftypevr
  14674. @deftypevr {@code{files-configuration} parameter} string log-file-perm
  14675. Specifies the permissions for all log files that the scheduler writes.
  14676. Defaults to @samp{"0644"}.
  14677. @end deftypevr
  14678. @deftypevr {@code{files-configuration} parameter} log-location page-log
  14679. Defines the page log filename. Specifying a blank filename disables
  14680. page log generation. The value @code{stderr} causes log entries to be
  14681. sent to the standard error file when the scheduler is running in the
  14682. foreground, or to the system log daemon when run in the background. The
  14683. value @code{syslog} causes log entries to be sent to the system log
  14684. daemon. The server name may be included in filenames using the string
  14685. @code{%s}, as in @code{/var/log/cups/%s-page_log}.
  14686. Defaults to @samp{"/var/log/cups/page_log"}.
  14687. @end deftypevr
  14688. @deftypevr {@code{files-configuration} parameter} string remote-root
  14689. Specifies the username that is associated with unauthenticated accesses
  14690. by clients claiming to be the root user. The default is @code{remroot}.
  14691. Defaults to @samp{"remroot"}.
  14692. @end deftypevr
  14693. @deftypevr {@code{files-configuration} parameter} file-name request-root
  14694. Specifies the directory that contains print jobs and other HTTP request
  14695. data.
  14696. Defaults to @samp{"/var/spool/cups"}.
  14697. @end deftypevr
  14698. @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
  14699. Specifies the level of security sandboxing that is applied to print
  14700. filters, backends, and other child processes of the scheduler; either
  14701. @code{relaxed} or @code{strict}. This directive is currently only
  14702. used/supported on macOS.
  14703. Defaults to @samp{strict}.
  14704. @end deftypevr
  14705. @deftypevr {@code{files-configuration} parameter} file-name server-keychain
  14706. Specifies the location of TLS certificates and private keys. CUPS will
  14707. look for public and private keys in this directory: @file{.crt} files
  14708. for PEM-encoded certificates and corresponding @file{.key} files for
  14709. PEM-encoded private keys.
  14710. Defaults to @samp{"/etc/cups/ssl"}.
  14711. @end deftypevr
  14712. @deftypevr {@code{files-configuration} parameter} file-name server-root
  14713. Specifies the directory containing the server configuration files.
  14714. Defaults to @samp{"/etc/cups"}.
  14715. @end deftypevr
  14716. @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
  14717. Specifies whether the scheduler calls fsync(2) after writing
  14718. configuration or state files.
  14719. Defaults to @samp{#f}.
  14720. @end deftypevr
  14721. @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
  14722. Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
  14723. @end deftypevr
  14724. @deftypevr {@code{files-configuration} parameter} file-name temp-dir
  14725. Specifies the directory where temporary files are stored.
  14726. Defaults to @samp{"/var/spool/cups/tmp"}.
  14727. @end deftypevr
  14728. @deftypevr {@code{files-configuration} parameter} string user
  14729. Specifies the user name or ID that is used when running external
  14730. programs.
  14731. Defaults to @samp{"lp"}.
  14732. @end deftypevr
  14733. @deftypevr {@code{files-configuration} parameter} string set-env
  14734. Set the specified environment variable to be passed to child processes.
  14735. Defaults to @samp{"variable value"}.
  14736. @end deftypevr
  14737. @end deftypevr
  14738. @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
  14739. Specifies the logging level for the AccessLog file. The @code{config}
  14740. level logs when printers and classes are added, deleted, or modified and
  14741. when configuration files are accessed or updated. The @code{actions}
  14742. level logs when print jobs are submitted, held, released, modified, or
  14743. canceled, and any of the conditions for @code{config}. The @code{all}
  14744. level logs all requests.
  14745. Defaults to @samp{actions}.
  14746. @end deftypevr
  14747. @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
  14748. Specifies whether to purge job history data automatically when it is no
  14749. longer required for quotas.
  14750. Defaults to @samp{#f}.
  14751. @end deftypevr
  14752. @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
  14753. Specifies a list of DNS-SD sub-types to advertise for each shared printer.
  14754. For example, @samp{"_cups" "_print"} will tell network clients that both
  14755. CUPS sharing and IPP Everywhere are supported.
  14756. Defaults to @samp{"_cups"}.
  14757. @end deftypevr
  14758. @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
  14759. Specifies which protocols to use for local printer sharing.
  14760. Defaults to @samp{dnssd}.
  14761. @end deftypevr
  14762. @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
  14763. Specifies whether the CUPS web interface is advertised.
  14764. Defaults to @samp{#f}.
  14765. @end deftypevr
  14766. @deftypevr {@code{cups-configuration} parameter} boolean browsing?
  14767. Specifies whether shared printers are advertised.
  14768. Defaults to @samp{#f}.
  14769. @end deftypevr
  14770. @deftypevr {@code{cups-configuration} parameter} string classification
  14771. Specifies the security classification of the server. Any valid banner
  14772. name can be used, including @samp{"classified"}, @samp{"confidential"},
  14773. @samp{"secret"}, @samp{"topsecret"}, and @samp{"unclassified"}, or the
  14774. banner can be omitted to disable secure printing functions.
  14775. Defaults to @samp{""}.
  14776. @end deftypevr
  14777. @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
  14778. Specifies whether users may override the classification (cover page) of
  14779. individual print jobs using the @code{job-sheets} option.
  14780. Defaults to @samp{#f}.
  14781. @end deftypevr
  14782. @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
  14783. Specifies the default type of authentication to use.
  14784. Defaults to @samp{Basic}.
  14785. @end deftypevr
  14786. @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
  14787. Specifies whether encryption will be used for authenticated requests.
  14788. Defaults to @samp{Required}.
  14789. @end deftypevr
  14790. @deftypevr {@code{cups-configuration} parameter} string default-language
  14791. Specifies the default language to use for text and web content.
  14792. Defaults to @samp{"en"}.
  14793. @end deftypevr
  14794. @deftypevr {@code{cups-configuration} parameter} string default-paper-size
  14795. Specifies the default paper size for new print queues. @samp{"Auto"}
  14796. uses a locale-specific default, while @samp{"None"} specifies there is
  14797. no default paper size. Specific size names are typically
  14798. @samp{"Letter"} or @samp{"A4"}.
  14799. Defaults to @samp{"Auto"}.
  14800. @end deftypevr
  14801. @deftypevr {@code{cups-configuration} parameter} string default-policy
  14802. Specifies the default access policy to use.
  14803. Defaults to @samp{"default"}.
  14804. @end deftypevr
  14805. @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
  14806. Specifies whether local printers are shared by default.
  14807. Defaults to @samp{#t}.
  14808. @end deftypevr
  14809. @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
  14810. Specifies the delay for updating of configuration and state files, in
  14811. seconds. A value of 0 causes the update to happen as soon as possible,
  14812. typically within a few milliseconds.
  14813. Defaults to @samp{30}.
  14814. @end deftypevr
  14815. @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
  14816. Specifies what to do when an error occurs. Possible values are
  14817. @code{abort-job}, which will discard the failed print job;
  14818. @code{retry-job}, which will retry the job at a later time;
  14819. @code{retry-current-job}, which retries the failed job immediately; and
  14820. @code{stop-printer}, which stops the printer.
  14821. Defaults to @samp{stop-printer}.
  14822. @end deftypevr
  14823. @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
  14824. Specifies the maximum cost of filters that are run concurrently, which
  14825. can be used to minimize disk, memory, and CPU resource problems. A
  14826. limit of 0 disables filter limiting. An average print to a
  14827. non-PostScript printer needs a filter limit of about 200. A PostScript
  14828. printer needs about half that (100). Setting the limit below these
  14829. thresholds will effectively limit the scheduler to printing a single job
  14830. at any time.
  14831. Defaults to @samp{0}.
  14832. @end deftypevr
  14833. @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
  14834. Specifies the scheduling priority of filters that are run to print a
  14835. job. The nice value ranges from 0, the highest priority, to 19, the
  14836. lowest priority.
  14837. Defaults to @samp{0}.
  14838. @end deftypevr
  14839. @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
  14840. Specifies whether to do reverse lookups on connecting clients. The
  14841. @code{double} setting causes @code{cupsd} to verify that the hostname
  14842. resolved from the address matches one of the addresses returned for that
  14843. hostname. Double lookups also prevent clients with unregistered
  14844. addresses from connecting to your server. Only set this option to
  14845. @code{#t} or @code{double} if absolutely required.
  14846. Defaults to @samp{#f}.
  14847. @end deftypevr
  14848. @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
  14849. Specifies the number of seconds to wait before killing the filters and
  14850. backend associated with a canceled or held job.
  14851. Defaults to @samp{30}.
  14852. @end deftypevr
  14853. @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
  14854. Specifies the interval between retries of jobs in seconds. This is
  14855. typically used for fax queues but can also be used with normal print
  14856. queues whose error policy is @code{retry-job} or
  14857. @code{retry-current-job}.
  14858. Defaults to @samp{30}.
  14859. @end deftypevr
  14860. @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
  14861. Specifies the number of retries that are done for jobs. This is
  14862. typically used for fax queues but can also be used with normal print
  14863. queues whose error policy is @code{retry-job} or
  14864. @code{retry-current-job}.
  14865. Defaults to @samp{5}.
  14866. @end deftypevr
  14867. @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
  14868. Specifies whether to support HTTP keep-alive connections.
  14869. Defaults to @samp{#t}.
  14870. @end deftypevr
  14871. @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
  14872. Specifies how long an idle client connection remains open, in seconds.
  14873. Defaults to @samp{30}.
  14874. @end deftypevr
  14875. @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
  14876. Specifies the maximum size of print files, IPP requests, and HTML form
  14877. data. A limit of 0 disables the limit check.
  14878. Defaults to @samp{0}.
  14879. @end deftypevr
  14880. @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
  14881. Listens on the specified interfaces for connections. Valid values are
  14882. of the form @var{address}:@var{port}, where @var{address} is either an
  14883. IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
  14884. indicate all addresses. Values can also be file names of local UNIX
  14885. domain sockets. The Listen directive is similar to the Port directive
  14886. but allows you to restrict access to specific interfaces or networks.
  14887. @end deftypevr
  14888. @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
  14889. Specifies the number of pending connections that will be allowed. This
  14890. normally only affects very busy servers that have reached the MaxClients
  14891. limit, but can also be triggered by large numbers of simultaneous
  14892. connections. When the limit is reached, the operating system will
  14893. refuse additional connections until the scheduler can accept the pending
  14894. ones.
  14895. Defaults to @samp{128}.
  14896. @end deftypevr
  14897. @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
  14898. Specifies a set of additional access controls.
  14899. Available @code{location-access-controls} fields are:
  14900. @deftypevr {@code{location-access-controls} parameter} file-name path
  14901. Specifies the URI path to which the access control applies.
  14902. @end deftypevr
  14903. @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
  14904. Access controls for all access to this path, in the same format as the
  14905. @code{access-controls} of @code{operation-access-control}.
  14906. Defaults to @samp{()}.
  14907. @end deftypevr
  14908. @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
  14909. Access controls for method-specific access to this path.
  14910. Defaults to @samp{()}.
  14911. Available @code{method-access-controls} fields are:
  14912. @deftypevr {@code{method-access-controls} parameter} boolean reverse?
  14913. If @code{#t}, apply access controls to all methods except the listed
  14914. methods. Otherwise apply to only the listed methods.
  14915. Defaults to @samp{#f}.
  14916. @end deftypevr
  14917. @deftypevr {@code{method-access-controls} parameter} method-list methods
  14918. Methods to which this access control applies.
  14919. Defaults to @samp{()}.
  14920. @end deftypevr
  14921. @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
  14922. Access control directives, as a list of strings. Each string should be
  14923. one directive, such as @samp{"Order allow,deny"}.
  14924. Defaults to @samp{()}.
  14925. @end deftypevr
  14926. @end deftypevr
  14927. @end deftypevr
  14928. @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
  14929. Specifies the number of debugging messages that are retained for logging
  14930. if an error occurs in a print job. Debug messages are logged regardless
  14931. of the LogLevel setting.
  14932. Defaults to @samp{100}.
  14933. @end deftypevr
  14934. @deftypevr {@code{cups-configuration} parameter} log-level log-level
  14935. Specifies the level of logging for the ErrorLog file. The value
  14936. @code{none} stops all logging while @code{debug2} logs everything.
  14937. Defaults to @samp{info}.
  14938. @end deftypevr
  14939. @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
  14940. Specifies the format of the date and time in the log files. The value
  14941. @code{standard} logs whole seconds while @code{usecs} logs microseconds.
  14942. Defaults to @samp{standard}.
  14943. @end deftypevr
  14944. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
  14945. Specifies the maximum number of simultaneous clients that are allowed by
  14946. the scheduler.
  14947. Defaults to @samp{100}.
  14948. @end deftypevr
  14949. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
  14950. Specifies the maximum number of simultaneous clients that are allowed
  14951. from a single address.
  14952. Defaults to @samp{100}.
  14953. @end deftypevr
  14954. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
  14955. Specifies the maximum number of copies that a user can print of each
  14956. job.
  14957. Defaults to @samp{9999}.
  14958. @end deftypevr
  14959. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
  14960. Specifies the maximum time a job may remain in the @code{indefinite}
  14961. hold state before it is canceled. A value of 0 disables cancellation of
  14962. held jobs.
  14963. Defaults to @samp{0}.
  14964. @end deftypevr
  14965. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
  14966. Specifies the maximum number of simultaneous jobs that are allowed. Set
  14967. to 0 to allow an unlimited number of jobs.
  14968. Defaults to @samp{500}.
  14969. @end deftypevr
  14970. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
  14971. Specifies the maximum number of simultaneous jobs that are allowed per
  14972. printer. A value of 0 allows up to MaxJobs jobs per printer.
  14973. Defaults to @samp{0}.
  14974. @end deftypevr
  14975. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
  14976. Specifies the maximum number of simultaneous jobs that are allowed per
  14977. user. A value of 0 allows up to MaxJobs jobs per user.
  14978. Defaults to @samp{0}.
  14979. @end deftypevr
  14980. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
  14981. Specifies the maximum time a job may take to print before it is
  14982. canceled, in seconds. Set to 0 to disable cancellation of ``stuck'' jobs.
  14983. Defaults to @samp{10800}.
  14984. @end deftypevr
  14985. @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
  14986. Specifies the maximum size of the log files before they are rotated, in
  14987. bytes. The value 0 disables log rotation.
  14988. Defaults to @samp{1048576}.
  14989. @end deftypevr
  14990. @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
  14991. Specifies the maximum amount of time to allow between files in a
  14992. multiple file print job, in seconds.
  14993. Defaults to @samp{300}.
  14994. @end deftypevr
  14995. @deftypevr {@code{cups-configuration} parameter} string page-log-format
  14996. Specifies the format of PageLog lines. Sequences beginning with percent
  14997. (@samp{%}) characters are replaced with the corresponding information,
  14998. while all other characters are copied literally. The following percent
  14999. sequences are recognized:
  15000. @table @samp
  15001. @item %%
  15002. insert a single percent character
  15003. @item %@{name@}
  15004. insert the value of the specified IPP attribute
  15005. @item %C
  15006. insert the number of copies for the current page
  15007. @item %P
  15008. insert the current page number
  15009. @item %T
  15010. insert the current date and time in common log format
  15011. @item %j
  15012. insert the job ID
  15013. @item %p
  15014. insert the printer name
  15015. @item %u
  15016. insert the username
  15017. @end table
  15018. A value of the empty string disables page logging. The string @code{%p
  15019. %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
  15020. %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
  15021. standard items.
  15022. Defaults to @samp{""}.
  15023. @end deftypevr
  15024. @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
  15025. Passes the specified environment variable(s) to child processes; a list
  15026. of strings.
  15027. Defaults to @samp{()}.
  15028. @end deftypevr
  15029. @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
  15030. Specifies named access control policies.
  15031. Available @code{policy-configuration} fields are:
  15032. @deftypevr {@code{policy-configuration} parameter} string name
  15033. Name of the policy.
  15034. @end deftypevr
  15035. @deftypevr {@code{policy-configuration} parameter} string job-private-access
  15036. Specifies an access list for a job's private values. @code{@@ACL} maps
  15037. to the printer's requesting-user-name-allowed or
  15038. requesting-user-name-denied values. @code{@@OWNER} maps to the job's
  15039. owner. @code{@@SYSTEM} maps to the groups listed for the
  15040. @code{system-group} field of the @code{files-config} configuration,
  15041. which is reified into the @code{cups-files.conf(5)} file. Other
  15042. possible elements of the access list include specific user names, and
  15043. @code{@@@var{group}} to indicate members of a specific group. The
  15044. access list may also be simply @code{all} or @code{default}.
  15045. Defaults to @samp{"@@OWNER @@SYSTEM"}.
  15046. @end deftypevr
  15047. @deftypevr {@code{policy-configuration} parameter} string job-private-values
  15048. Specifies the list of job values to make private, or @code{all},
  15049. @code{default}, or @code{none}.
  15050. Defaults to @samp{"job-name job-originating-host-name
  15051. job-originating-user-name phone"}.
  15052. @end deftypevr
  15053. @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
  15054. Specifies an access list for a subscription's private values.
  15055. @code{@@ACL} maps to the printer's requesting-user-name-allowed or
  15056. requesting-user-name-denied values. @code{@@OWNER} maps to the job's
  15057. owner. @code{@@SYSTEM} maps to the groups listed for the
  15058. @code{system-group} field of the @code{files-config} configuration,
  15059. which is reified into the @code{cups-files.conf(5)} file. Other
  15060. possible elements of the access list include specific user names, and
  15061. @code{@@@var{group}} to indicate members of a specific group. The
  15062. access list may also be simply @code{all} or @code{default}.
  15063. Defaults to @samp{"@@OWNER @@SYSTEM"}.
  15064. @end deftypevr
  15065. @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
  15066. Specifies the list of job values to make private, or @code{all},
  15067. @code{default}, or @code{none}.
  15068. Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
  15069. notify-subscriber-user-name notify-user-data"}.
  15070. @end deftypevr
  15071. @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
  15072. Access control by IPP operation.
  15073. Defaults to @samp{()}.
  15074. @end deftypevr
  15075. @end deftypevr
  15076. @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
  15077. Specifies whether job files (documents) are preserved after a job is
  15078. printed. If a numeric value is specified, job files are preserved for
  15079. the indicated number of seconds after printing. Otherwise a boolean
  15080. value applies indefinitely.
  15081. Defaults to @samp{86400}.
  15082. @end deftypevr
  15083. @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
  15084. Specifies whether the job history is preserved after a job is printed.
  15085. If a numeric value is specified, the job history is preserved for the
  15086. indicated number of seconds after printing. If @code{#t}, the job
  15087. history is preserved until the MaxJobs limit is reached.
  15088. Defaults to @samp{#t}.
  15089. @end deftypevr
  15090. @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
  15091. Specifies the amount of time to wait for job completion before
  15092. restarting the scheduler.
  15093. Defaults to @samp{30}.
  15094. @end deftypevr
  15095. @deftypevr {@code{cups-configuration} parameter} string rip-cache
  15096. Specifies the maximum amount of memory to use when converting documents
  15097. into bitmaps for a printer.
  15098. Defaults to @samp{"128m"}.
  15099. @end deftypevr
  15100. @deftypevr {@code{cups-configuration} parameter} string server-admin
  15101. Specifies the email address of the server administrator.
  15102. Defaults to @samp{"root@@localhost.localdomain"}.
  15103. @end deftypevr
  15104. @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
  15105. The ServerAlias directive is used for HTTP Host header validation when
  15106. clients connect to the scheduler from external interfaces. Using the
  15107. special name @code{*} can expose your system to known browser-based DNS
  15108. rebinding attacks, even when accessing sites through a firewall. If the
  15109. auto-discovery of alternate names does not work, we recommend listing
  15110. each alternate name with a ServerAlias directive instead of using
  15111. @code{*}.
  15112. Defaults to @samp{*}.
  15113. @end deftypevr
  15114. @deftypevr {@code{cups-configuration} parameter} string server-name
  15115. Specifies the fully-qualified host name of the server.
  15116. Defaults to @samp{"localhost"}.
  15117. @end deftypevr
  15118. @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
  15119. Specifies what information is included in the Server header of HTTP
  15120. responses. @code{None} disables the Server header. @code{ProductOnly}
  15121. reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
  15122. reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
  15123. @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
  15124. the output of the @code{uname} command. @code{Full} reports @code{CUPS
  15125. 2.0.0 (@var{uname}) IPP/2.0}.
  15126. Defaults to @samp{Minimal}.
  15127. @end deftypevr
  15128. @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
  15129. Listens on the specified interfaces for encrypted connections. Valid
  15130. values are of the form @var{address}:@var{port}, where @var{address} is
  15131. either an IPv6 address enclosed in brackets, an IPv4 address, or
  15132. @code{*} to indicate all addresses.
  15133. Defaults to @samp{()}.
  15134. @end deftypevr
  15135. @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
  15136. Sets encryption options. By default, CUPS only supports encryption
  15137. using TLS v1.0 or higher using known secure cipher suites. Security is
  15138. reduced when @code{Allow} options are used, and enhanced when @code{Deny}
  15139. options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
  15140. suites, which are required for some older clients. The @code{AllowSSL3} option
  15141. enables SSL v3.0, which is required for some older clients that do not support
  15142. TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
  15143. @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
  15144. protocol version to TLS v1.1.
  15145. Defaults to @samp{()}.
  15146. @end deftypevr
  15147. @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
  15148. Specifies whether the scheduler requires clients to strictly adhere to
  15149. the IPP specifications.
  15150. Defaults to @samp{#f}.
  15151. @end deftypevr
  15152. @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
  15153. Specifies the HTTP request timeout, in seconds.
  15154. Defaults to @samp{300}.
  15155. @end deftypevr
  15156. @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
  15157. Specifies whether the web interface is enabled.
  15158. Defaults to @samp{#f}.
  15159. @end deftypevr
  15160. At this point you're probably thinking ``oh dear, Guix manual, I like
  15161. you but you can stop already with the configuration options''. Indeed.
  15162. However, one more point: it could be that you have an existing
  15163. @code{cupsd.conf} that you want to use. In that case, you can pass an
  15164. @code{opaque-cups-configuration} as the configuration of a
  15165. @code{cups-service-type}.
  15166. Available @code{opaque-cups-configuration} fields are:
  15167. @deftypevr {@code{opaque-cups-configuration} parameter} package cups
  15168. The CUPS package.
  15169. @end deftypevr
  15170. @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
  15171. The contents of the @code{cupsd.conf}, as a string.
  15172. @end deftypevr
  15173. @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
  15174. The contents of the @code{cups-files.conf} file, as a string.
  15175. @end deftypevr
  15176. For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
  15177. strings of the same name, you could instantiate a CUPS service like
  15178. this:
  15179. @lisp
  15180. (service cups-service-type
  15181. (opaque-cups-configuration
  15182. (cupsd.conf cupsd.conf)
  15183. (cups-files.conf cups-files.conf)))
  15184. @end lisp
  15185. @node Desktop Services
  15186. @subsection Desktop Services
  15187. The @code{(gnu services desktop)} module provides services that are
  15188. usually useful in the context of a ``desktop'' setup---that is, on a
  15189. machine running a graphical display server, possibly with graphical user
  15190. interfaces, etc. It also defines services that provide specific desktop
  15191. environments like GNOME, Xfce or MATE.
  15192. To simplify things, the module defines a variable containing the set of
  15193. services that users typically expect on a machine with a graphical
  15194. environment and networking:
  15195. @defvr {Scheme Variable} %desktop-services
  15196. This is a list of services that builds upon @code{%base-services} and
  15197. adds or adjusts services for a typical ``desktop'' setup.
  15198. In particular, it adds a graphical login manager (@pxref{X Window,
  15199. @code{gdm-service-type}}), screen lockers, a network management tool
  15200. (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
  15201. support (@pxref{Networking Services, @code{modem-manager-service-type}}),
  15202. energy and color management services, the @code{elogind} login and seat
  15203. manager, the Polkit privilege service, the GeoClue location service, the
  15204. AccountsService daemon that allows authorized users change system passwords,
  15205. an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
  15206. name service switch service configured to be able to use @code{nss-mdns}
  15207. (@pxref{Name Service Switch, mDNS}).
  15208. @end defvr
  15209. The @code{%desktop-services} variable can be used as the @code{services}
  15210. field of an @code{operating-system} declaration (@pxref{operating-system
  15211. Reference, @code{services}}).
  15212. Additionally, the @code{gnome-desktop-service-type},
  15213. @code{xfce-desktop-service}, @code{mate-desktop-service-type},
  15214. @code{lxqt-desktop-service-type} and @code{enlightenment-desktop-service-type}
  15215. procedures can add GNOME, Xfce, MATE and/or Enlightenment to a system. To
  15216. ``add GNOME'' means that system-level services like the backlight adjustment
  15217. helpers and the power management utilities are added to the system, extending
  15218. @code{polkit} and @code{dbus} appropriately, allowing GNOME to operate with
  15219. elevated privileges on a limited number of special-purpose system interfaces.
  15220. Additionally, adding a service made by @code{gnome-desktop-service-type} adds
  15221. the GNOME metapackage to the system profile. Likewise, adding the Xfce
  15222. service not only adds the @code{xfce} metapackage to the system profile, but
  15223. it also gives the Thunar file manager the ability to open a ``root-mode'' file
  15224. management window, if the user authenticates using the administrator's
  15225. password via the standard polkit graphical interface. To ``add MATE'' means
  15226. that @code{polkit} and @code{dbus} are extended appropriately, allowing MATE
  15227. to operate with elevated privileges on a limited number of special-purpose
  15228. system interfaces. Additionally, adding a service of type
  15229. @code{mate-desktop-service-type} adds the MATE metapackage to the system
  15230. profile. ``Adding Enlightenment'' means that @code{dbus} is extended
  15231. appropriately, and several of Enlightenment's binaries are set as setuid,
  15232. allowing Enlightenment's screen locker and other functionality to work as
  15233. expected.
  15234. The desktop environments in Guix use the Xorg display server by
  15235. default. If you'd like to use the newer display server protocol
  15236. called Wayland, you need to use the @code{sddm-service} instead of
  15237. GDM as the graphical login manager. You should then
  15238. select the ``GNOME (Wayland)'' session in SDDM@. Alternatively you can
  15239. also try starting GNOME on Wayland manually from a TTY with the
  15240. command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
  15241. gnome-session``. Currently only GNOME has support for Wayland.
  15242. @defvr {Scheme Variable} gnome-desktop-service-type
  15243. This is the type of the service that adds the @uref{https://www.gnome.org,
  15244. GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
  15245. object (see below).
  15246. This service adds the @code{gnome} package to the system profile, and extends
  15247. polkit with the actions from @code{gnome-settings-daemon}.
  15248. @end defvr
  15249. @deftp {Data Type} gnome-desktop-configuration
  15250. Configuration record for the GNOME desktop environment.
  15251. @table @asis
  15252. @item @code{gnome} (default: @code{gnome})
  15253. The GNOME package to use.
  15254. @end table
  15255. @end deftp
  15256. @defvr {Scheme Variable} xfce-desktop-service-type
  15257. This is the type of a service to run the @uref{Xfce, https://xfce.org/}
  15258. desktop environment. Its value is an @code{xfce-desktop-configuration} object
  15259. (see below).
  15260. This service adds the @code{xfce} package to the system profile, and
  15261. extends polkit with the ability for @code{thunar} to manipulate the file
  15262. system as root from within a user session, after the user has authenticated
  15263. with the administrator's password.
  15264. Note that @code{xfce4-panel} and its plugin packages should be installed in
  15265. the same profile to ensure compatibility. When using this service, you should
  15266. add extra plugins (@code{xfce4-whiskermenu-plugin},
  15267. @code{xfce4-weather-plugin}, etc.) to the @code{packages} field of your
  15268. @code{operating-system}.
  15269. @end defvr
  15270. @deftp {Data Type} xfce-desktop-configuration
  15271. Configuration record for the Xfce desktop environment.
  15272. @table @asis
  15273. @item @code{xfce} (default: @code{xfce})
  15274. The Xfce package to use.
  15275. @end table
  15276. @end deftp
  15277. @deffn {Scheme Variable} mate-desktop-service-type
  15278. This is the type of the service that runs the @uref{https://mate-desktop.org/,
  15279. MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
  15280. object (see below).
  15281. This service adds the @code{mate} package to the system
  15282. profile, and extends polkit with the actions from
  15283. @code{mate-settings-daemon}.
  15284. @end deffn
  15285. @deftp {Data Type} mate-desktop-configuration
  15286. Configuration record for the MATE desktop environment.
  15287. @table @asis
  15288. @item @code{mate} (default: @code{mate})
  15289. The MATE package to use.
  15290. @end table
  15291. @end deftp
  15292. @deffn {Scheme Variable} lxqt-desktop-service-type
  15293. This is the type of the service that runs the @uref{https://lxqt.github.io,
  15294. LXQt desktop environment}. Its value is a @code{lxqt-desktop-configuration}
  15295. object (see below).
  15296. This service adds the @code{lxqt} package to the system
  15297. profile.
  15298. @end deffn
  15299. @deftp {Data Type} lxqt-desktop-configuration
  15300. Configuration record for the LXQt desktop environment.
  15301. @table @asis
  15302. @item @code{lxqt} (default: @code{lxqt})
  15303. The LXQT package to use.
  15304. @end table
  15305. @end deftp
  15306. @deffn {Scheme Variable} enlightenment-desktop-service-type
  15307. Return a service that adds the @code{enlightenment} package to the system
  15308. profile, and extends dbus with actions from @code{efl}.
  15309. @end deffn
  15310. @deftp {Data Type} enlightenment-desktop-service-configuration
  15311. @table @asis
  15312. @item @code{enlightenment} (default: @code{enlightenment})
  15313. The enlightenment package to use.
  15314. @end table
  15315. @end deftp
  15316. Because the GNOME, Xfce and MATE desktop services pull in so many packages,
  15317. the default @code{%desktop-services} variable doesn't include any of
  15318. them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
  15319. @code{%desktop-services} in the @code{services} field of your
  15320. @code{operating-system}:
  15321. @lisp
  15322. (use-modules (gnu))
  15323. (use-service-modules desktop)
  15324. (operating-system
  15325. ...
  15326. ;; cons* adds items to the list given as its last argument.
  15327. (services (cons* (service gnome-desktop-service-type)
  15328. (service xfce-desktop-service)
  15329. %desktop-services))
  15330. ...)
  15331. @end lisp
  15332. These desktop environments will then be available as options in the
  15333. graphical login window.
  15334. The actual service definitions included in @code{%desktop-services} and
  15335. provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
  15336. are described below.
  15337. @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
  15338. Return a service that runs the ``system bus'', using @var{dbus}, with
  15339. support for @var{services}.
  15340. @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
  15341. facility. Its system bus is used to allow system services to communicate
  15342. and to be notified of system-wide events.
  15343. @var{services} must be a list of packages that provide an
  15344. @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
  15345. and policy files. For example, to allow avahi-daemon to use the system bus,
  15346. @var{services} must be equal to @code{(list avahi)}.
  15347. @end deffn
  15348. @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
  15349. Return a service that runs the @code{elogind} login and
  15350. seat management daemon. @uref{https://github.com/elogind/elogind,
  15351. Elogind} exposes a D-Bus interface that can be used to know which users
  15352. are logged in, know what kind of sessions they have open, suspend the
  15353. system, inhibit system suspend, reboot the system, and other tasks.
  15354. Elogind handles most system-level power events for a computer, for
  15355. example suspending the system when a lid is closed, or shutting it down
  15356. when the power button is pressed.
  15357. The @var{config} keyword argument specifies the configuration for
  15358. elogind, and should be the result of an @code{(elogind-configuration
  15359. (@var{parameter} @var{value})...)} invocation. Available parameters and
  15360. their default values are:
  15361. @table @code
  15362. @item kill-user-processes?
  15363. @code{#f}
  15364. @item kill-only-users
  15365. @code{()}
  15366. @item kill-exclude-users
  15367. @code{("root")}
  15368. @item inhibit-delay-max-seconds
  15369. @code{5}
  15370. @item handle-power-key
  15371. @code{poweroff}
  15372. @item handle-suspend-key
  15373. @code{suspend}
  15374. @item handle-hibernate-key
  15375. @code{hibernate}
  15376. @item handle-lid-switch
  15377. @code{suspend}
  15378. @item handle-lid-switch-docked
  15379. @code{ignore}
  15380. @item handle-lid-switch-external-power
  15381. @code{ignore}
  15382. @item power-key-ignore-inhibited?
  15383. @code{#f}
  15384. @item suspend-key-ignore-inhibited?
  15385. @code{#f}
  15386. @item hibernate-key-ignore-inhibited?
  15387. @code{#f}
  15388. @item lid-switch-ignore-inhibited?
  15389. @code{#t}
  15390. @item holdoff-timeout-seconds
  15391. @code{30}
  15392. @item idle-action
  15393. @code{ignore}
  15394. @item idle-action-seconds
  15395. @code{(* 30 60)}
  15396. @item runtime-directory-size-percent
  15397. @code{10}
  15398. @item runtime-directory-size
  15399. @code{#f}
  15400. @item remove-ipc?
  15401. @code{#t}
  15402. @item suspend-state
  15403. @code{("mem" "standby" "freeze")}
  15404. @item suspend-mode
  15405. @code{()}
  15406. @item hibernate-state
  15407. @code{("disk")}
  15408. @item hibernate-mode
  15409. @code{("platform" "shutdown")}
  15410. @item hybrid-sleep-state
  15411. @code{("disk")}
  15412. @item hybrid-sleep-mode
  15413. @code{("suspend" "platform" "shutdown")}
  15414. @end table
  15415. @end deffn
  15416. @deffn {Scheme Procedure} accountsservice-service @
  15417. [#:accountsservice @var{accountsservice}]
  15418. Return a service that runs AccountsService, a system service that can
  15419. list available accounts, change their passwords, and so on.
  15420. AccountsService integrates with PolicyKit to enable unprivileged users
  15421. to acquire the capability to modify their system configuration.
  15422. @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
  15423. accountsservice web site} for more information.
  15424. The @var{accountsservice} keyword argument is the @code{accountsservice}
  15425. package to expose as a service.
  15426. @end deffn
  15427. @deffn {Scheme Procedure} polkit-service @
  15428. [#:polkit @var{polkit}]
  15429. Return a service that runs the
  15430. @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
  15431. management service}, which allows system administrators to grant access to
  15432. privileged operations in a structured way. By querying the Polkit service, a
  15433. privileged system component can know when it should grant additional
  15434. capabilities to ordinary users. For example, an ordinary user can be granted
  15435. the capability to suspend the system if the user is logged in locally.
  15436. @end deffn
  15437. @defvr {Scheme Variable} polkit-wheel-service
  15438. Service that adds the @code{wheel} group as admins to the Polkit
  15439. service. This makes it so that users in the @code{wheel} group are queried
  15440. for their own passwords when performing administrative actions instead of
  15441. @code{root}'s, similar to the behaviour used by @code{sudo}.
  15442. @end defvr
  15443. @defvr {Scheme Variable} upower-service-type
  15444. Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
  15445. system-wide monitor for power consumption and battery levels, with the given
  15446. configuration settings.
  15447. It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
  15448. notably used by GNOME.
  15449. @end defvr
  15450. @deftp {Data Type} upower-configuration
  15451. Data type representation the configuration for UPower.
  15452. @table @asis
  15453. @item @code{upower} (default: @var{upower})
  15454. Package to use for @code{upower}.
  15455. @item @code{watts-up-pro?} (default: @code{#f})
  15456. Enable the Watts Up Pro device.
  15457. @item @code{poll-batteries?} (default: @code{#t})
  15458. Enable polling the kernel for battery level changes.
  15459. @item @code{ignore-lid?} (default: @code{#f})
  15460. Ignore the lid state, this can be useful if it's incorrect on a device.
  15461. @item @code{use-percentage-for-policy?} (default: @code{#f})
  15462. Whether battery percentage based policy should be used. The default is to use
  15463. the time left, change to @code{#t} to use the percentage.
  15464. @item @code{percentage-low} (default: @code{10})
  15465. When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
  15466. at which the battery is considered low.
  15467. @item @code{percentage-critical} (default: @code{3})
  15468. When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
  15469. at which the battery is considered critical.
  15470. @item @code{percentage-action} (default: @code{2})
  15471. When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
  15472. at which action will be taken.
  15473. @item @code{time-low} (default: @code{1200})
  15474. When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
  15475. seconds at which the battery is considered low.
  15476. @item @code{time-critical} (default: @code{300})
  15477. When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
  15478. seconds at which the battery is considered critical.
  15479. @item @code{time-action} (default: @code{120})
  15480. When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
  15481. seconds at which action will be taken.
  15482. @item @code{critical-power-action} (default: @code{'hybrid-sleep})
  15483. The action taken when @code{percentage-action} or @code{time-action} is
  15484. reached (depending on the configuration of @code{use-percentage-for-policy?}).
  15485. Possible values are:
  15486. @itemize @bullet
  15487. @item
  15488. @code{'power-off}
  15489. @item
  15490. @code{'hibernate}
  15491. @item
  15492. @code{'hybrid-sleep}.
  15493. @end itemize
  15494. @end table
  15495. @end deftp
  15496. @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
  15497. Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
  15498. UDisks}, a @dfn{disk management} daemon that provides user interfaces
  15499. with notifications and ways to mount/unmount disks. Programs that talk
  15500. to UDisks include the @command{udisksctl} command, part of UDisks, and
  15501. GNOME Disks. Note that Udisks relies on the @command{mount} command, so
  15502. it will only be able to use the file-system utilities installed in the
  15503. system profile. For example if you want to be able to mount NTFS
  15504. file-systems in read and write fashion, you'll need to have
  15505. @code{ntfs-3g} installed system-wide.
  15506. @end deffn
  15507. @deffn {Scheme Variable} colord-service-type
  15508. This is the type of the service that runs @command{colord}, a system
  15509. service with a D-Bus
  15510. interface to manage the color profiles of input and output devices such as
  15511. screens and scanners. It is notably used by the GNOME Color Manager graphical
  15512. tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
  15513. site} for more information.
  15514. @end deffn
  15515. @cindex scanner access
  15516. @defvr {Scheme Variable} sane-service-type
  15517. This service provides access to scanners @i{via}
  15518. @uref{http://www.sane-project.org, SANE} by installing the necessary
  15519. udev rules. It is included in @code{%desktop-services} (@pxref{Desktop
  15520. Services}) and relies by default on @code{sane-backends-minimal} package
  15521. (see below) for hardware support.
  15522. @end defvr
  15523. @defvr {Scheme Variable} sane-backends-minimal
  15524. The default package which the @code{sane-service-type} installs. It
  15525. supports many recent scanners.
  15526. @end defvr
  15527. @defvr {Scheme Variable} sane-backends
  15528. This package includes support for all scanners that
  15529. @code{sane-backends-minimal} supports, plus older Hewlett-Packard
  15530. scanners supported by @code{hplip} package. In order to use this on
  15531. a system which relies on @code{%desktop-services}, you may use
  15532. @code{modify-services} (@pxref{Service Reference,
  15533. @code{modify-services}}) as illustrated below:
  15534. @lisp
  15535. (use-modules (gnu))
  15536. (use-service-modules
  15537. @dots{}
  15538. desktop)
  15539. (use-package-modules
  15540. @dots{}
  15541. scanner)
  15542. (define %my-desktop-services
  15543. ;; List of desktop services that supports a broader range of scanners.
  15544. (modify-services %desktop-services
  15545. (sane-service-type _ => sane-backends)))
  15546. (operating-system
  15547. @dots{}
  15548. (services %my-desktop-services)
  15549. @end lisp
  15550. @end defvr
  15551. @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
  15552. Return a configuration allowing an application to access GeoClue
  15553. location data. @var{name} is the Desktop ID of the application, without
  15554. the @code{.desktop} part. If @var{allowed?} is true, the application
  15555. will have access to location information by default. The boolean
  15556. @var{system?} value indicates whether an application is a system component
  15557. or not. Finally @var{users} is a list of UIDs of all users for which
  15558. this application is allowed location info access. An empty users list
  15559. means that all users are allowed.
  15560. @end deffn
  15561. @defvr {Scheme Variable} %standard-geoclue-applications
  15562. The standard list of well-known GeoClue application configurations,
  15563. granting authority to the GNOME date-and-time utility to ask for the
  15564. current location in order to set the time zone, and allowing the
  15565. IceCat and Epiphany web browsers to request location information.
  15566. IceCat and Epiphany both query the user before allowing a web page to
  15567. know the user's location.
  15568. @end defvr
  15569. @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
  15570. [#:whitelist '()] @
  15571. [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
  15572. [#:submit-data? #f]
  15573. [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
  15574. [#:submission-nick "geoclue"] @
  15575. [#:applications %standard-geoclue-applications]
  15576. Return a service that runs the GeoClue location service. This service
  15577. provides a D-Bus interface to allow applications to request access to a
  15578. user's physical location, and optionally to add information to online
  15579. location databases. See
  15580. @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
  15581. web site} for more information.
  15582. @end deffn
  15583. @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
  15584. [@w{#:auto-enable? #f}]
  15585. Return a service that runs the @command{bluetoothd} daemon, which
  15586. manages all the Bluetooth devices and provides a number of D-Bus
  15587. interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
  15588. powered automatically at boot, which can be useful when using a
  15589. bluetooth keyboard or mouse.
  15590. Users need to be in the @code{lp} group to access the D-Bus service.
  15591. @end deffn
  15592. @defvr {Scheme Variable} gnome-keyring-service-type
  15593. This is the type of the service that adds the
  15594. @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
  15595. value is a @code{gnome-keyring-configuration} object (see below).
  15596. This service adds the @code{gnome-keyring} package to the system profile
  15597. and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
  15598. a user's login keyring when they log in or setting its password with passwd.
  15599. @end defvr
  15600. @deftp {Data Type} gnome-keyring-configuration
  15601. Configuration record for the GNOME Keyring service.
  15602. @table @asis
  15603. @item @code{keyring} (default: @code{gnome-keyring})
  15604. The GNOME keyring package to use.
  15605. @item @code{pam-services}
  15606. A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
  15607. services to extend, where @var{service} is the name of an existing
  15608. service to extend and @var{kind} is one of @code{login} or
  15609. @code{passwd}.
  15610. If @code{login} is given, it adds an optional
  15611. @code{pam_gnome_keyring.so} to the auth block without arguments and to
  15612. the session block with @code{auto_start}. If @code{passwd} is given, it
  15613. adds an optional @code{pam_gnome_keyring.so} to the password block
  15614. without arguments.
  15615. By default, this field contains ``gdm-password'' with the value @code{login}
  15616. and ``passwd'' is with the value @code{passwd}.
  15617. @end table
  15618. @end deftp
  15619. @node Sound Services
  15620. @subsection Sound Services
  15621. @cindex sound support
  15622. @cindex ALSA
  15623. @cindex PulseAudio, sound support
  15624. The @code{(gnu services sound)} module provides a service to configure the
  15625. Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
  15626. preferred ALSA output driver.
  15627. @deffn {Scheme Variable} alsa-service-type
  15628. This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
  15629. Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
  15630. configuration file. The value for this type is a @command{alsa-configuration}
  15631. record as in this example:
  15632. @lisp
  15633. (service alsa-service-type)
  15634. @end lisp
  15635. See below for details about @code{alsa-configuration}.
  15636. @end deffn
  15637. @deftp {Data Type} alsa-configuration
  15638. Data type representing the configuration for @code{alsa-service}.
  15639. @table @asis
  15640. @item @code{alsa-plugins} (default: @var{alsa-plugins})
  15641. @code{alsa-plugins} package to use.
  15642. @item @code{pulseaudio?} (default: @var{#t})
  15643. Whether ALSA applications should transparently be made to use the
  15644. @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
  15645. Using PulseAudio allows you to run several sound-producing applications
  15646. at the same time and to individual control them @i{via}
  15647. @command{pavucontrol}, among other things.
  15648. @item @code{extra-options} (default: @var{""})
  15649. String to append to the @file{/etc/asound.conf} file.
  15650. @end table
  15651. @end deftp
  15652. Individual users who want to override the system configuration of ALSA can do
  15653. it with the @file{~/.asoundrc} file:
  15654. @example
  15655. # In guix, we have to specify the absolute path for plugins.
  15656. pcm_type.jack @{
  15657. lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
  15658. @}
  15659. # Routing ALSA to jack:
  15660. # <http://jackaudio.org/faq/routing_alsa.html>.
  15661. pcm.rawjack @{
  15662. type jack
  15663. playback_ports @{
  15664. 0 system:playback_1
  15665. 1 system:playback_2
  15666. @}
  15667. capture_ports @{
  15668. 0 system:capture_1
  15669. 1 system:capture_2
  15670. @}
  15671. @}
  15672. pcm.!default @{
  15673. type plug
  15674. slave @{
  15675. pcm "rawjack"
  15676. @}
  15677. @}
  15678. @end example
  15679. See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
  15680. details.
  15681. @deffn {Scheme Variable} pulseaudio-service-type
  15682. This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
  15683. sound server. It exists to allow system overrides of the default settings
  15684. via @code{pulseaudio-configuration}, see below.
  15685. @quotation Warning
  15686. This service overrides per-user configuration files. If you want
  15687. PulseAudio to honor configuration files in @file{~/.config/pulse} you
  15688. have to unset the environment variables @env{PULSE_CONFIG} and
  15689. @env{PULSE_CLIENTCONFIG} in your @file{~/.bash_profile}.
  15690. @end quotation
  15691. @quotation Warning
  15692. This service on its own does not ensure, that the @code{pulseaudio} package
  15693. exists on your machine. It merely adds configuration files for it, as
  15694. detailed below. In the (admittedly unlikely) case, that you find yourself
  15695. without a @code{pulseaudio} package, consider enabling it through the
  15696. @code{alsa-service-type} above.
  15697. @end quotation
  15698. @end deffn
  15699. @deftp {Data Type} pulseaudio-configuration
  15700. Data type representing the configuration for @code{pulseaudio-service}.
  15701. @table @asis
  15702. @item @code{client-conf} (default: @code{'()})
  15703. List of settings to set in @file{client.conf}.
  15704. Accepts a list of strings or a symbol-value pairs. A string will be
  15705. inserted as-is with a newline added. A pair will be formatted as
  15706. ``key = value'', again with a newline added.
  15707. @item @code{daemon-conf} (default: @code{'((flat-volumes . no))})
  15708. List of settings to set in @file{daemon.conf}, formatted just like
  15709. @var{client-conf}.
  15710. @item @code{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
  15711. Script file to use as @file{default.pa}.
  15712. @item @code{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
  15713. Script file to use as @file{system.pa}.
  15714. @end table
  15715. @end deftp
  15716. @deffn {Scheme Variable} ladspa-service-type
  15717. This service sets the @var{LADSPA_PATH} variable, so that programs, which
  15718. respect it, e.g. PulseAudio, can load LADSPA plugins.
  15719. The following example will setup the service to enable modules from the
  15720. @code{swh-plugins} package:
  15721. @lisp
  15722. (service ladspa-service-type
  15723. (ladspa-configuration (plugins (list swh-plugins))))
  15724. @end lisp
  15725. See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
  15726. details.
  15727. @end deffn
  15728. @node Database Services
  15729. @subsection Database Services
  15730. @cindex database
  15731. @cindex SQL
  15732. The @code{(gnu services databases)} module provides the following services.
  15733. @subsubheading PostgreSQL
  15734. The following example describes a PostgreSQL service with the default
  15735. configuration.
  15736. @lisp
  15737. (service postgresql-service-type
  15738. (postgresql-configuration
  15739. (postgresql postgresql-10)))
  15740. @end lisp
  15741. If the services fails to start, it may be due to an incompatible
  15742. cluster already present in @var{data-directory}. Adjust it (or, if you
  15743. don't need the cluster anymore, delete @var{data-directory}), then
  15744. restart the service.
  15745. Peer authentication is used by default and the @code{postgres} user
  15746. account has no shell, which prevents the direct execution of @code{psql}
  15747. commands as this user. To use @code{psql}, you can temporarily log in
  15748. as @code{postgres} using a shell, create a PostgreSQL superuser with the
  15749. same name as one of the system users and then create the associated
  15750. database.
  15751. @example
  15752. sudo -u postgres -s /bin/sh
  15753. createuser --interactive
  15754. createdb $MY_USER_LOGIN # Replace appropriately.
  15755. @end example
  15756. @deftp {Data Type} postgresql-configuration
  15757. Data type representing the configuration for the
  15758. @code{postgresql-service-type}.
  15759. @table @asis
  15760. @item @code{postgresql}
  15761. PostgreSQL package to use for the service.
  15762. @item @code{port} (default: @code{5432})
  15763. Port on which PostgreSQL should listen.
  15764. @item @code{locale} (default: @code{"en_US.utf8"})
  15765. Locale to use as the default when creating the database cluster.
  15766. @item @code{config-file} (default: @code{(postgresql-config-file)})
  15767. The configuration file to use when running PostgreSQL@. The default
  15768. behaviour uses the postgresql-config-file record with the default values
  15769. for the fields.
  15770. @item @code{log-directory} (default: @code{"/var/log/postgresql"})
  15771. The directory where @command{pg_ctl} output will be written in a file
  15772. named @code{"pg_ctl.log"}. This file can be useful to debug PostgreSQL
  15773. configuration errors for instance.
  15774. @item @code{data-directory} (default: @code{"/var/lib/postgresql/data"})
  15775. Directory in which to store the data.
  15776. @item @code{extension-packages} (default: @code{'()})
  15777. @cindex postgresql extension-packages
  15778. Additional extensions are loaded from packages listed in
  15779. @var{extension-packages}. Extensions are available at runtime. For instance,
  15780. to create a geographic database using the @code{postgis} extension, a user can
  15781. configure the postgresql-service as in this example:
  15782. @cindex postgis
  15783. @lisp
  15784. (use-package-modules databases geo)
  15785. (operating-system
  15786. ...
  15787. ;; postgresql is required to run `psql' but postgis is not required for
  15788. ;; proper operation.
  15789. (packages (cons* postgresql %base-packages))
  15790. (services
  15791. (cons*
  15792. (service postgresql-service-type
  15793. (postgresql-configuration
  15794. (postgresql postgresql-10)
  15795. (extension-packages (list postgis))))
  15796. %base-services)))
  15797. @end lisp
  15798. Then the extension becomes visible and you can initialise an empty geographic
  15799. database in this way:
  15800. @example
  15801. psql -U postgres
  15802. > create database postgistest;
  15803. > \connect postgistest;
  15804. > create extension postgis;
  15805. > create extension postgis_topology;
  15806. @end example
  15807. There is no need to add this field for contrib extensions such as hstore or
  15808. dblink as they are already loadable by postgresql. This field is only
  15809. required to add extensions provided by other packages.
  15810. @end table
  15811. @end deftp
  15812. @deftp {Data Type} postgresql-config-file
  15813. Data type representing the PostgreSQL configuration file. As shown in
  15814. the following example, this can be used to customize the configuration
  15815. of PostgreSQL@. Note that you can use any G-expression or filename in
  15816. place of this record, if you already have a configuration file you'd
  15817. like to use for example.
  15818. @lisp
  15819. (service postgresql-service-type
  15820. (postgresql-configuration
  15821. (config-file
  15822. (postgresql-config-file
  15823. (log-destination "stderr")
  15824. (hba-file
  15825. (plain-file "pg_hba.conf"
  15826. "
  15827. local all all trust
  15828. host all all 127.0.0.1/32 md5
  15829. host all all ::1/128 md5"))
  15830. (extra-config
  15831. '(("session_preload_libraries" "auto_explain")
  15832. ("random_page_cost" 2)
  15833. ("auto_explain.log_min_duration" "100 ms")
  15834. ("work_mem" "500 MB")
  15835. ("logging_collector" #t)
  15836. ("log_directory" "/var/log/postgresql")))))))
  15837. @end lisp
  15838. @table @asis
  15839. @item @code{log-destination} (default: @code{"syslog"})
  15840. The logging method to use for PostgreSQL@. Multiple values are accepted,
  15841. separated by commas.
  15842. @item @code{hba-file} (default: @code{%default-postgres-hba})
  15843. Filename or G-expression for the host-based authentication
  15844. configuration.
  15845. @item @code{ident-file} (default: @code{%default-postgres-ident})
  15846. Filename or G-expression for the user name mapping configuration.
  15847. @item @code{socket-directory} (default: @code{"/var/run/postgresql"})
  15848. Specifies the directory of the Unix-domain socket(s) on which PostgreSQL
  15849. is to listen for connections from client applications. If set to
  15850. @code{#false} PostgreSQL does not listen on any Unix-domain sockets, in
  15851. which case only TCP/IP sockets can be used to connect to the server.
  15852. @item @code{extra-config} (default: @code{'()})
  15853. List of additional keys and values to include in the PostgreSQL config
  15854. file. Each entry in the list should be a list where the first element
  15855. is the key, and the remaining elements are the values.
  15856. The values can be numbers, booleans or strings and will be mapped to
  15857. PostgreSQL parameters types @code{Boolean}, @code{String},
  15858. @code{Numeric}, @code{Numeric with Unit} and @code{Enumerated} described
  15859. @uref{https://www.postgresql.org/docs/current/config-setting.html,
  15860. here}.
  15861. @end table
  15862. @end deftp
  15863. @deffn {Scheme Variable} postgresql-role-service-type
  15864. This service allows to create PostgreSQL roles and databases after
  15865. PostgreSQL service start. Here is an example of its use.
  15866. @lisp
  15867. (service postgresql-role-service-type
  15868. (postgresql-role-configuration
  15869. (roles
  15870. (list (postgresql-role
  15871. (name "test")
  15872. (create-database? #t))))))
  15873. @end lisp
  15874. This service can be extended with extra roles, as in this
  15875. example:
  15876. @lisp
  15877. (service-extension postgresql-role-service-type
  15878. (const (postgresql-role
  15879. (name "alice")
  15880. (create-database? #t))))
  15881. @end lisp
  15882. @end deffn
  15883. @deftp {Data Type} postgresql-role
  15884. PostgreSQL manages database access permissions using the concept of
  15885. roles. A role can be thought of as either a database user, or a group
  15886. of database users, depending on how the role is set up. Roles can own
  15887. database objects (for example, tables) and can assign privileges on
  15888. those objects to other roles to control who has access to which objects.
  15889. @table @asis
  15890. @item @code{name}
  15891. The role name.
  15892. @item @code{permissions} (default: @code{'(createdb login)})
  15893. The role permissions list. Supported permissions are @code{bypassrls},
  15894. @code{createdb}, @code{createrole}, @code{login}, @code{replication} and
  15895. @code{superuser}.
  15896. @item @code{create-database?} (default: @code{#f})
  15897. Whether to create a database with the same name as the role.
  15898. @end table
  15899. @end deftp
  15900. @deftp {Data Type} postgresql-role-configuration
  15901. Data type representing the configuration of
  15902. @var{postgresql-role-service-type}.
  15903. @table @asis
  15904. @item @code{host} (default: @code{"/var/run/postgresql"})
  15905. The PostgreSQL host to connect to.
  15906. @item @code{log} (default: @code{"/var/log/postgresql_roles.log"})
  15907. File name of the log file.
  15908. @item @code{roles} (default: @code{'()})
  15909. The initial PostgreSQL roles to create.
  15910. @end table
  15911. @end deftp
  15912. @subsubheading MariaDB/MySQL
  15913. @defvr {Scheme Variable} mysql-service-type
  15914. This is the service type for a MySQL or MariaDB database server. Its value
  15915. is a @code{mysql-configuration} object that specifies which package to use,
  15916. as well as various settings for the @command{mysqld} daemon.
  15917. @end defvr
  15918. @deftp {Data Type} mysql-configuration
  15919. Data type representing the configuration of @var{mysql-service-type}.
  15920. @table @asis
  15921. @item @code{mysql} (default: @var{mariadb})
  15922. Package object of the MySQL database server, can be either @var{mariadb}
  15923. or @var{mysql}.
  15924. For MySQL, a temporary root password will be displayed at activation time.
  15925. For MariaDB, the root password is empty.
  15926. @item @code{bind-address} (default: @code{"127.0.0.1"})
  15927. The IP on which to listen for network connections. Use @code{"0.0.0.0"}
  15928. to bind to all available network interfaces.
  15929. @item @code{port} (default: @code{3306})
  15930. TCP port on which the database server listens for incoming connections.
  15931. @item @code{socket} (default: @code{"/run/mysqld/mysqld.sock"})
  15932. Socket file to use for local (non-network) connections.
  15933. @item @code{extra-content} (default: @code{""})
  15934. Additional settings for the @file{my.cnf} configuration file.
  15935. @item @code{auto-upgrade?} (default: @code{#t})
  15936. Whether to automatically run @command{mysql_upgrade} after starting the
  15937. service. This is necessary to upgrade the @dfn{system schema} after
  15938. ``major'' updates (such as switching from MariaDB 10.4 to 10.5), but can
  15939. be disabled if you would rather do that manually.
  15940. @end table
  15941. @end deftp
  15942. @subsubheading Memcached
  15943. @defvr {Scheme Variable} memcached-service-type
  15944. This is the service type for the @uref{https://memcached.org/,
  15945. Memcached} service, which provides a distributed in memory cache. The
  15946. value for the service type is a @code{memcached-configuration} object.
  15947. @end defvr
  15948. @lisp
  15949. (service memcached-service-type)
  15950. @end lisp
  15951. @deftp {Data Type} memcached-configuration
  15952. Data type representing the configuration of memcached.
  15953. @table @asis
  15954. @item @code{memcached} (default: @code{memcached})
  15955. The Memcached package to use.
  15956. @item @code{interfaces} (default: @code{'("0.0.0.0")})
  15957. Network interfaces on which to listen.
  15958. @item @code{tcp-port} (default: @code{11211})
  15959. Port on which to accept connections.
  15960. @item @code{udp-port} (default: @code{11211})
  15961. Port on which to accept UDP connections on, a value of 0 will disable
  15962. listening on a UDP socket.
  15963. @item @code{additional-options} (default: @code{'()})
  15964. Additional command line options to pass to @code{memcached}.
  15965. @end table
  15966. @end deftp
  15967. @subsubheading Redis
  15968. @defvr {Scheme Variable} redis-service-type
  15969. This is the service type for the @uref{https://redis.io/, Redis}
  15970. key/value store, whose value is a @code{redis-configuration} object.
  15971. @end defvr
  15972. @deftp {Data Type} redis-configuration
  15973. Data type representing the configuration of redis.
  15974. @table @asis
  15975. @item @code{redis} (default: @code{redis})
  15976. The Redis package to use.
  15977. @item @code{bind} (default: @code{"127.0.0.1"})
  15978. Network interface on which to listen.
  15979. @item @code{port} (default: @code{6379})
  15980. Port on which to accept connections on, a value of 0 will disable
  15981. listening on a TCP socket.
  15982. @item @code{working-directory} (default: @code{"/var/lib/redis"})
  15983. Directory in which to store the database and related files.
  15984. @end table
  15985. @end deftp
  15986. @node Mail Services
  15987. @subsection Mail Services
  15988. @cindex mail
  15989. @cindex email
  15990. The @code{(gnu services mail)} module provides Guix service definitions
  15991. for email services: IMAP, POP3, and LMTP servers, as well as mail
  15992. transport agents (MTAs). Lots of acronyms! These services are detailed
  15993. in the subsections below.
  15994. @subsubheading Dovecot Service
  15995. @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
  15996. Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
  15997. @end deffn
  15998. By default, Dovecot does not need much configuration; the default
  15999. configuration object created by @code{(dovecot-configuration)} will
  16000. suffice if your mail is delivered to @code{~/Maildir}. A self-signed
  16001. certificate will be generated for TLS-protected connections, though
  16002. Dovecot will also listen on cleartext ports by default. There are a
  16003. number of options, though, which mail administrators might need to change,
  16004. and as is the case with other services, Guix allows the system
  16005. administrator to specify these parameters via a uniform Scheme interface.
  16006. For example, to specify that mail is located at @code{maildir~/.mail},
  16007. one would instantiate the Dovecot service like this:
  16008. @lisp
  16009. (dovecot-service #:config
  16010. (dovecot-configuration
  16011. (mail-location "maildir:~/.mail")))
  16012. @end lisp
  16013. The available configuration parameters follow. Each parameter
  16014. definition is preceded by its type; for example, @samp{string-list foo}
  16015. indicates that the @code{foo} parameter should be specified as a list of
  16016. strings. There is also a way to specify the configuration as a string,
  16017. if you have an old @code{dovecot.conf} file that you want to port over
  16018. from some other system; see the end for more details.
  16019. @c The following documentation was initially generated by
  16020. @c (generate-documentation) in (gnu services mail). Manually maintained
  16021. @c documentation is better, so we shouldn't hesitate to edit below as
  16022. @c needed. However if the change you want to make to this documentation
  16023. @c can be done in an automated way, it's probably easier to change
  16024. @c (generate-documentation) than to make it below and have to deal with
  16025. @c the churn as dovecot updates.
  16026. Available @code{dovecot-configuration} fields are:
  16027. @deftypevr {@code{dovecot-configuration} parameter} package dovecot
  16028. The dovecot package.
  16029. @end deftypevr
  16030. @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
  16031. A list of IPs or hosts where to listen for connections. @samp{*}
  16032. listens on all IPv4 interfaces, @samp{::} listens on all IPv6
  16033. interfaces. If you want to specify non-default ports or anything more
  16034. complex, customize the address and port fields of the
  16035. @samp{inet-listener} of the specific services you are interested in.
  16036. @end deftypevr
  16037. @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
  16038. List of protocols we want to serve. Available protocols include
  16039. @samp{imap}, @samp{pop3}, and @samp{lmtp}.
  16040. Available @code{protocol-configuration} fields are:
  16041. @deftypevr {@code{protocol-configuration} parameter} string name
  16042. The name of the protocol.
  16043. @end deftypevr
  16044. @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
  16045. UNIX socket path to the master authentication server to find users.
  16046. This is used by imap (for shared users) and lda.
  16047. It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
  16048. @end deftypevr
  16049. @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
  16050. Space separated list of plugins to load.
  16051. @end deftypevr
  16052. @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
  16053. Maximum number of IMAP connections allowed for a user from each IP
  16054. address. NOTE: The username is compared case-sensitively.
  16055. Defaults to @samp{10}.
  16056. @end deftypevr
  16057. @end deftypevr
  16058. @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
  16059. List of services to enable. Available services include @samp{imap},
  16060. @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
  16061. @samp{lmtp}.
  16062. Available @code{service-configuration} fields are:
  16063. @deftypevr {@code{service-configuration} parameter} string kind
  16064. The service kind. Valid values include @code{director},
  16065. @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
  16066. @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
  16067. @code{tcpwrap}, @code{quota-warning}, or anything else.
  16068. @end deftypevr
  16069. @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
  16070. Listeners for the service. A listener is either a
  16071. @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
  16072. an @code{inet-listener-configuration}.
  16073. Defaults to @samp{()}.
  16074. Available @code{unix-listener-configuration} fields are:
  16075. @deftypevr {@code{unix-listener-configuration} parameter} string path
  16076. Path to the file, relative to @code{base-dir} field. This is also used as
  16077. the section name.
  16078. @end deftypevr
  16079. @deftypevr {@code{unix-listener-configuration} parameter} string mode
  16080. The access mode for the socket.
  16081. Defaults to @samp{"0600"}.
  16082. @end deftypevr
  16083. @deftypevr {@code{unix-listener-configuration} parameter} string user
  16084. The user to own the socket.
  16085. Defaults to @samp{""}.
  16086. @end deftypevr
  16087. @deftypevr {@code{unix-listener-configuration} parameter} string group
  16088. The group to own the socket.
  16089. Defaults to @samp{""}.
  16090. @end deftypevr
  16091. Available @code{fifo-listener-configuration} fields are:
  16092. @deftypevr {@code{fifo-listener-configuration} parameter} string path
  16093. Path to the file, relative to @code{base-dir} field. This is also used as
  16094. the section name.
  16095. @end deftypevr
  16096. @deftypevr {@code{fifo-listener-configuration} parameter} string mode
  16097. The access mode for the socket.
  16098. Defaults to @samp{"0600"}.
  16099. @end deftypevr
  16100. @deftypevr {@code{fifo-listener-configuration} parameter} string user
  16101. The user to own the socket.
  16102. Defaults to @samp{""}.
  16103. @end deftypevr
  16104. @deftypevr {@code{fifo-listener-configuration} parameter} string group
  16105. The group to own the socket.
  16106. Defaults to @samp{""}.
  16107. @end deftypevr
  16108. Available @code{inet-listener-configuration} fields are:
  16109. @deftypevr {@code{inet-listener-configuration} parameter} string protocol
  16110. The protocol to listen for.
  16111. @end deftypevr
  16112. @deftypevr {@code{inet-listener-configuration} parameter} string address
  16113. The address on which to listen, or empty for all addresses.
  16114. Defaults to @samp{""}.
  16115. @end deftypevr
  16116. @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
  16117. The port on which to listen.
  16118. @end deftypevr
  16119. @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
  16120. Whether to use SSL for this service; @samp{yes}, @samp{no}, or
  16121. @samp{required}.
  16122. Defaults to @samp{#t}.
  16123. @end deftypevr
  16124. @end deftypevr
  16125. @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
  16126. Maximum number of simultaneous client connections per process. Once
  16127. this number of connections is received, the next incoming connection
  16128. will prompt Dovecot to spawn another process. If set to 0,
  16129. @code{default-client-limit} is used instead.
  16130. Defaults to @samp{0}.
  16131. @end deftypevr
  16132. @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
  16133. Number of connections to handle before starting a new process.
  16134. Typically the only useful values are 0 (unlimited) or 1. 1 is more
  16135. secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
  16136. Defaults to @samp{1}.
  16137. @end deftypevr
  16138. @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
  16139. Maximum number of processes that can exist for this service. If set to
  16140. 0, @code{default-process-limit} is used instead.
  16141. Defaults to @samp{0}.
  16142. @end deftypevr
  16143. @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
  16144. Number of processes to always keep waiting for more connections.
  16145. Defaults to @samp{0}.
  16146. @end deftypevr
  16147. @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
  16148. If you set @samp{service-count 0}, you probably need to grow
  16149. this.
  16150. Defaults to @samp{256000000}.
  16151. @end deftypevr
  16152. @end deftypevr
  16153. @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
  16154. Dict configuration, as created by the @code{dict-configuration}
  16155. constructor.
  16156. Available @code{dict-configuration} fields are:
  16157. @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
  16158. A list of key-value pairs that this dict should hold.
  16159. Defaults to @samp{()}.
  16160. @end deftypevr
  16161. @end deftypevr
  16162. @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
  16163. A list of passdb configurations, each one created by the
  16164. @code{passdb-configuration} constructor.
  16165. Available @code{passdb-configuration} fields are:
  16166. @deftypevr {@code{passdb-configuration} parameter} string driver
  16167. The driver that the passdb should use. Valid values include
  16168. @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
  16169. @samp{static}.
  16170. Defaults to @samp{"pam"}.
  16171. @end deftypevr
  16172. @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
  16173. Space separated list of arguments to the passdb driver.
  16174. Defaults to @samp{""}.
  16175. @end deftypevr
  16176. @end deftypevr
  16177. @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
  16178. List of userdb configurations, each one created by the
  16179. @code{userdb-configuration} constructor.
  16180. Available @code{userdb-configuration} fields are:
  16181. @deftypevr {@code{userdb-configuration} parameter} string driver
  16182. The driver that the userdb should use. Valid values include
  16183. @samp{passwd} and @samp{static}.
  16184. Defaults to @samp{"passwd"}.
  16185. @end deftypevr
  16186. @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
  16187. Space separated list of arguments to the userdb driver.
  16188. Defaults to @samp{""}.
  16189. @end deftypevr
  16190. @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
  16191. Override fields from passwd.
  16192. Defaults to @samp{()}.
  16193. @end deftypevr
  16194. @end deftypevr
  16195. @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
  16196. Plug-in configuration, created by the @code{plugin-configuration}
  16197. constructor.
  16198. @end deftypevr
  16199. @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
  16200. List of namespaces. Each item in the list is created by the
  16201. @code{namespace-configuration} constructor.
  16202. Available @code{namespace-configuration} fields are:
  16203. @deftypevr {@code{namespace-configuration} parameter} string name
  16204. Name for this namespace.
  16205. @end deftypevr
  16206. @deftypevr {@code{namespace-configuration} parameter} string type
  16207. Namespace type: @samp{private}, @samp{shared} or @samp{public}.
  16208. Defaults to @samp{"private"}.
  16209. @end deftypevr
  16210. @deftypevr {@code{namespace-configuration} parameter} string separator
  16211. Hierarchy separator to use. You should use the same separator for
  16212. all namespaces or some clients get confused. @samp{/} is usually a good
  16213. one. The default however depends on the underlying mail storage
  16214. format.
  16215. Defaults to @samp{""}.
  16216. @end deftypevr
  16217. @deftypevr {@code{namespace-configuration} parameter} string prefix
  16218. Prefix required to access this namespace. This needs to be
  16219. different for all namespaces. For example @samp{Public/}.
  16220. Defaults to @samp{""}.
  16221. @end deftypevr
  16222. @deftypevr {@code{namespace-configuration} parameter} string location
  16223. Physical location of the mailbox. This is in the same format as
  16224. mail_location, which is also the default for it.
  16225. Defaults to @samp{""}.
  16226. @end deftypevr
  16227. @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
  16228. There can be only one INBOX, and this setting defines which
  16229. namespace has it.
  16230. Defaults to @samp{#f}.
  16231. @end deftypevr
  16232. @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
  16233. If namespace is hidden, it's not advertised to clients via NAMESPACE
  16234. extension. You'll most likely also want to set @samp{list? #f}. This is mostly
  16235. useful when converting from another server with different namespaces
  16236. which you want to deprecate but still keep working. For example you can
  16237. create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
  16238. and @samp{mail/}.
  16239. Defaults to @samp{#f}.
  16240. @end deftypevr
  16241. @deftypevr {@code{namespace-configuration} parameter} boolean list?
  16242. Show the mailboxes under this namespace with the LIST command. This
  16243. makes the namespace visible for clients that do not support the NAMESPACE
  16244. extension. The special @code{children} value lists child mailboxes, but
  16245. hides the namespace prefix.
  16246. Defaults to @samp{#t}.
  16247. @end deftypevr
  16248. @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
  16249. Namespace handles its own subscriptions. If set to @code{#f}, the
  16250. parent namespace handles them. The empty prefix should always have this
  16251. as @code{#t}).
  16252. Defaults to @samp{#t}.
  16253. @end deftypevr
  16254. @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
  16255. List of predefined mailboxes in this namespace.
  16256. Defaults to @samp{()}.
  16257. Available @code{mailbox-configuration} fields are:
  16258. @deftypevr {@code{mailbox-configuration} parameter} string name
  16259. Name for this mailbox.
  16260. @end deftypevr
  16261. @deftypevr {@code{mailbox-configuration} parameter} string auto
  16262. @samp{create} will automatically create this mailbox.
  16263. @samp{subscribe} will both create and subscribe to the mailbox.
  16264. Defaults to @samp{"no"}.
  16265. @end deftypevr
  16266. @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
  16267. List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
  16268. Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
  16269. @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
  16270. Defaults to @samp{()}.
  16271. @end deftypevr
  16272. @end deftypevr
  16273. @end deftypevr
  16274. @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
  16275. Base directory where to store runtime data.
  16276. Defaults to @samp{"/var/run/dovecot/"}.
  16277. @end deftypevr
  16278. @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
  16279. Greeting message for clients.
  16280. Defaults to @samp{"Dovecot ready."}.
  16281. @end deftypevr
  16282. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
  16283. List of trusted network ranges. Connections from these IPs are
  16284. allowed to override their IP addresses and ports (for logging and for
  16285. authentication checks). @samp{disable-plaintext-auth} is also ignored
  16286. for these networks. Typically you would specify your IMAP proxy servers
  16287. here.
  16288. Defaults to @samp{()}.
  16289. @end deftypevr
  16290. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
  16291. List of login access check sockets (e.g.@: tcpwrap).
  16292. Defaults to @samp{()}.
  16293. @end deftypevr
  16294. @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
  16295. Show more verbose process titles (in ps). Currently shows user name
  16296. and IP address. Useful for seeing who is actually using the IMAP
  16297. processes (e.g.@: shared mailboxes or if the same uid is used for multiple
  16298. accounts).
  16299. Defaults to @samp{#f}.
  16300. @end deftypevr
  16301. @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
  16302. Should all processes be killed when Dovecot master process shuts down.
  16303. Setting this to @code{#f} means that Dovecot can be upgraded without
  16304. forcing existing client connections to close (although that could also
  16305. be a problem if the upgrade is e.g.@: due to a security fix).
  16306. Defaults to @samp{#t}.
  16307. @end deftypevr
  16308. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
  16309. If non-zero, run mail commands via this many connections to doveadm
  16310. server, instead of running them directly in the same process.
  16311. Defaults to @samp{0}.
  16312. @end deftypevr
  16313. @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
  16314. UNIX socket or host:port used for connecting to doveadm server.
  16315. Defaults to @samp{"doveadm-server"}.
  16316. @end deftypevr
  16317. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
  16318. List of environment variables that are preserved on Dovecot startup
  16319. and passed down to all of its child processes. You can also give
  16320. key=value pairs to always set specific settings.
  16321. @end deftypevr
  16322. @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
  16323. Disable LOGIN command and all other plaintext authentications unless
  16324. SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
  16325. matches the local IP (i.e.@: you're connecting from the same computer),
  16326. the connection is considered secure and plaintext authentication is
  16327. allowed. See also ssl=required setting.
  16328. Defaults to @samp{#t}.
  16329. @end deftypevr
  16330. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
  16331. Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
  16332. Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
  16333. for caching to be used.
  16334. Defaults to @samp{0}.
  16335. @end deftypevr
  16336. @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
  16337. Time to live for cached data. After TTL expires the cached record
  16338. is no longer used, *except* if the main database lookup returns internal
  16339. failure. We also try to handle password changes automatically: If
  16340. user's previous authentication was successful, but this one wasn't, the
  16341. cache isn't used. For now this works only with plaintext
  16342. authentication.
  16343. Defaults to @samp{"1 hour"}.
  16344. @end deftypevr
  16345. @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
  16346. TTL for negative hits (user not found, password mismatch).
  16347. 0 disables caching them completely.
  16348. Defaults to @samp{"1 hour"}.
  16349. @end deftypevr
  16350. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
  16351. List of realms for SASL authentication mechanisms that need them.
  16352. You can leave it empty if you don't want to support multiple realms.
  16353. Many clients simply use the first one listed here, so keep the default
  16354. realm first.
  16355. Defaults to @samp{()}.
  16356. @end deftypevr
  16357. @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
  16358. Default realm/domain to use if none was specified. This is used for
  16359. both SASL realms and appending @@domain to username in plaintext
  16360. logins.
  16361. Defaults to @samp{""}.
  16362. @end deftypevr
  16363. @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
  16364. List of allowed characters in username. If the user-given username
  16365. contains a character not listed in here, the login automatically fails.
  16366. This is just an extra check to make sure user can't exploit any
  16367. potential quote escaping vulnerabilities with SQL/LDAP databases. If
  16368. you want to allow all characters, set this value to empty.
  16369. Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
  16370. @end deftypevr
  16371. @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
  16372. Username character translations before it's looked up from
  16373. databases. The value contains series of from -> to characters. For
  16374. example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
  16375. translated to @samp{@@}.
  16376. Defaults to @samp{""}.
  16377. @end deftypevr
  16378. @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
  16379. Username formatting before it's looked up from databases. You can
  16380. use the standard variables here, e.g.@: %Lu would lowercase the username,
  16381. %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
  16382. change the @samp{@@} into @samp{-AT-}. This translation is done after
  16383. @samp{auth-username-translation} changes.
  16384. Defaults to @samp{"%Lu"}.
  16385. @end deftypevr
  16386. @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
  16387. If you want to allow master users to log in by specifying the master
  16388. username within the normal username string (i.e.@: not using SASL
  16389. mechanism's support for it), you can specify the separator character
  16390. here. The format is then <username><separator><master username>.
  16391. UW-IMAP uses @samp{*} as the separator, so that could be a good
  16392. choice.
  16393. Defaults to @samp{""}.
  16394. @end deftypevr
  16395. @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
  16396. Username to use for users logging in with ANONYMOUS SASL
  16397. mechanism.
  16398. Defaults to @samp{"anonymous"}.
  16399. @end deftypevr
  16400. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
  16401. Maximum number of dovecot-auth worker processes. They're used to
  16402. execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
  16403. They're automatically created and destroyed as needed.
  16404. Defaults to @samp{30}.
  16405. @end deftypevr
  16406. @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
  16407. Host name to use in GSSAPI principal names. The default is to use
  16408. the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
  16409. allow all keytab entries.
  16410. Defaults to @samp{""}.
  16411. @end deftypevr
  16412. @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
  16413. Kerberos keytab to use for the GSSAPI mechanism. Will use the
  16414. system default (usually @file{/etc/krb5.keytab}) if not specified. You may
  16415. need to change the auth service to run as root to be able to read this
  16416. file.
  16417. Defaults to @samp{""}.
  16418. @end deftypevr
  16419. @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
  16420. Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
  16421. and @samp{ntlm-auth} helper.
  16422. <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
  16423. Defaults to @samp{#f}.
  16424. @end deftypevr
  16425. @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
  16426. Path for Samba's @samp{ntlm-auth} helper binary.
  16427. Defaults to @samp{"/usr/bin/ntlm_auth"}.
  16428. @end deftypevr
  16429. @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
  16430. Time to delay before replying to failed authentications.
  16431. Defaults to @samp{"2 secs"}.
  16432. @end deftypevr
  16433. @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
  16434. Require a valid SSL client certificate or the authentication
  16435. fails.
  16436. Defaults to @samp{#f}.
  16437. @end deftypevr
  16438. @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
  16439. Take the username from client's SSL certificate, using
  16440. @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
  16441. CommonName.
  16442. Defaults to @samp{#f}.
  16443. @end deftypevr
  16444. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
  16445. List of wanted authentication mechanisms. Supported mechanisms are:
  16446. @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
  16447. @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
  16448. @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
  16449. @samp{disable-plaintext-auth} setting.
  16450. @end deftypevr
  16451. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
  16452. List of IPs or hostnames to all director servers, including ourself.
  16453. Ports can be specified as ip:port. The default port is the same as what
  16454. director service's @samp{inet-listener} is using.
  16455. Defaults to @samp{()}.
  16456. @end deftypevr
  16457. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
  16458. List of IPs or hostnames to all backend mail servers. Ranges are
  16459. allowed too, like 10.0.0.10-10.0.0.30.
  16460. Defaults to @samp{()}.
  16461. @end deftypevr
  16462. @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
  16463. How long to redirect users to a specific server after it no longer
  16464. has any connections.
  16465. Defaults to @samp{"15 min"}.
  16466. @end deftypevr
  16467. @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
  16468. How the username is translated before being hashed. Useful values
  16469. include %Ln if user can log in with or without @@domain, %Ld if mailboxes
  16470. are shared within domain.
  16471. Defaults to @samp{"%Lu"}.
  16472. @end deftypevr
  16473. @deftypevr {@code{dovecot-configuration} parameter} string log-path
  16474. Log file to use for error messages. @samp{syslog} logs to syslog,
  16475. @samp{/dev/stderr} logs to stderr.
  16476. Defaults to @samp{"syslog"}.
  16477. @end deftypevr
  16478. @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
  16479. Log file to use for informational messages. Defaults to
  16480. @samp{log-path}.
  16481. Defaults to @samp{""}.
  16482. @end deftypevr
  16483. @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
  16484. Log file to use for debug messages. Defaults to
  16485. @samp{info-log-path}.
  16486. Defaults to @samp{""}.
  16487. @end deftypevr
  16488. @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
  16489. Syslog facility to use if you're logging to syslog. Usually if you
  16490. don't want to use @samp{mail}, you'll use local0..local7. Also other
  16491. standard facilities are supported.
  16492. Defaults to @samp{"mail"}.
  16493. @end deftypevr
  16494. @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
  16495. Log unsuccessful authentication attempts and the reasons why they
  16496. failed.
  16497. Defaults to @samp{#f}.
  16498. @end deftypevr
  16499. @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
  16500. In case of password mismatches, log the attempted password. Valid
  16501. values are no, plain and sha1. sha1 can be useful for detecting brute
  16502. force password attempts vs. user simply trying the same password over
  16503. and over again. You can also truncate the value to n chars by appending
  16504. ":n" (e.g.@: sha1:6).
  16505. Defaults to @samp{"no"}.
  16506. @end deftypevr
  16507. @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
  16508. Even more verbose logging for debugging purposes. Shows for example
  16509. SQL queries.
  16510. Defaults to @samp{#f}.
  16511. @end deftypevr
  16512. @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
  16513. In case of password mismatches, log the passwords and used scheme so
  16514. the problem can be debugged. Enabling this also enables
  16515. @samp{auth-debug}.
  16516. Defaults to @samp{#f}.
  16517. @end deftypevr
  16518. @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
  16519. Enable mail process debugging. This can help you figure out why
  16520. Dovecot isn't finding your mails.
  16521. Defaults to @samp{#f}.
  16522. @end deftypevr
  16523. @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
  16524. Show protocol level SSL errors.
  16525. Defaults to @samp{#f}.
  16526. @end deftypevr
  16527. @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
  16528. Prefix for each line written to log file. % codes are in
  16529. strftime(3) format.
  16530. Defaults to @samp{"\"%b %d %H:%M:%S \""}.
  16531. @end deftypevr
  16532. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
  16533. List of elements we want to log. The elements which have a
  16534. non-empty variable value are joined together to form a comma-separated
  16535. string.
  16536. @end deftypevr
  16537. @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
  16538. Login log format. %s contains @samp{login-log-format-elements}
  16539. string, %$ contains the data we want to log.
  16540. Defaults to @samp{"%$: %s"}.
  16541. @end deftypevr
  16542. @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
  16543. Log prefix for mail processes. See doc/wiki/Variables.txt for list
  16544. of possible variables you can use.
  16545. Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
  16546. @end deftypevr
  16547. @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
  16548. Format to use for logging mail deliveries. You can use variables:
  16549. @table @code
  16550. @item %$
  16551. Delivery status message (e.g.@: @samp{saved to INBOX})
  16552. @item %m
  16553. Message-ID
  16554. @item %s
  16555. Subject
  16556. @item %f
  16557. From address
  16558. @item %p
  16559. Physical size
  16560. @item %w
  16561. Virtual size.
  16562. @end table
  16563. Defaults to @samp{"msgid=%m: %$"}.
  16564. @end deftypevr
  16565. @deftypevr {@code{dovecot-configuration} parameter} string mail-location
  16566. Location for users' mailboxes. The default is empty, which means
  16567. that Dovecot tries to find the mailboxes automatically. This won't work
  16568. if the user doesn't yet have any mail, so you should explicitly tell
  16569. Dovecot the full location.
  16570. If you're using mbox, giving a path to the INBOX
  16571. file (e.g.@: @file{/var/mail/%u}) isn't enough. You'll also need to tell Dovecot
  16572. where the other mailboxes are kept. This is called the @emph{root mail
  16573. directory}, and it must be the first path given in the
  16574. @samp{mail-location} setting.
  16575. There are a few special variables you can use, e.g.:
  16576. @table @samp
  16577. @item %u
  16578. username
  16579. @item %n
  16580. user part in user@@domain, same as %u if there's no domain
  16581. @item %d
  16582. domain part in user@@domain, empty if there's no domain
  16583. @item %h
  16584. home director
  16585. @end table
  16586. See doc/wiki/Variables.txt for full list. Some examples:
  16587. @table @samp
  16588. @item maildir:~/Maildir
  16589. @item mbox:~/mail:INBOX=/var/mail/%u
  16590. @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
  16591. @end table
  16592. Defaults to @samp{""}.
  16593. @end deftypevr
  16594. @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
  16595. System user and group used to access mails. If you use multiple,
  16596. userdb can override these by returning uid or gid fields. You can use
  16597. either numbers or names. <doc/wiki/UserIds.txt>.
  16598. Defaults to @samp{""}.
  16599. @end deftypevr
  16600. @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
  16601. Defaults to @samp{""}.
  16602. @end deftypevr
  16603. @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
  16604. Group to enable temporarily for privileged operations. Currently
  16605. this is used only with INBOX when either its initial creation or
  16606. dotlocking fails. Typically this is set to @samp{"mail"} to give access to
  16607. @file{/var/mail}.
  16608. Defaults to @samp{""}.
  16609. @end deftypevr
  16610. @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
  16611. Grant access to these supplementary groups for mail processes.
  16612. Typically these are used to set up access to shared mailboxes. Note
  16613. that it may be dangerous to set these if users can create symlinks
  16614. (e.g.@: if @samp{mail} group is set here, @code{ln -s /var/mail ~/mail/var}
  16615. could allow a user to delete others' mailboxes, or @code{ln -s
  16616. /secret/shared/box ~/mail/mybox} would allow reading it). Defaults to
  16617. @samp{""}.
  16618. @end deftypevr
  16619. @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
  16620. Allow full file system access to clients. There's no access checks
  16621. other than what the operating system does for the active UID/GID@. It
  16622. works with both maildir and mboxes, allowing you to prefix mailboxes
  16623. names with e.g.@: @file{/path/} or @file{~user/}.
  16624. Defaults to @samp{#f}.
  16625. @end deftypevr
  16626. @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
  16627. Don't use @code{mmap()} at all. This is required if you store indexes to
  16628. shared file systems (NFS or clustered file system).
  16629. Defaults to @samp{#f}.
  16630. @end deftypevr
  16631. @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
  16632. Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
  16633. supports @samp{O_EXCL} since version 3, so this should be safe to use
  16634. nowadays by default.
  16635. Defaults to @samp{#t}.
  16636. @end deftypevr
  16637. @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
  16638. When to use fsync() or fdatasync() calls:
  16639. @table @code
  16640. @item optimized
  16641. Whenever necessary to avoid losing important data
  16642. @item always
  16643. Useful with e.g.@: NFS when @code{write()}s are delayed
  16644. @item never
  16645. Never use it (best performance, but crashes can lose data).
  16646. @end table
  16647. Defaults to @samp{"optimized"}.
  16648. @end deftypevr
  16649. @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
  16650. Mail storage exists in NFS@. Set this to yes to make Dovecot flush
  16651. NFS caches whenever needed. If you're using only a single mail server
  16652. this isn't needed.
  16653. Defaults to @samp{#f}.
  16654. @end deftypevr
  16655. @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
  16656. Mail index files also exist in NFS@. Setting this to yes requires
  16657. @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
  16658. Defaults to @samp{#f}.
  16659. @end deftypevr
  16660. @deftypevr {@code{dovecot-configuration} parameter} string lock-method
  16661. Locking method for index files. Alternatives are fcntl, flock and
  16662. dotlock. Dotlocking uses some tricks which may create more disk I/O
  16663. than other locking methods. NFS users: flock doesn't work, remember to
  16664. change @samp{mmap-disable}.
  16665. Defaults to @samp{"fcntl"}.
  16666. @end deftypevr
  16667. @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
  16668. Directory in which LDA/LMTP temporarily stores incoming mails >128
  16669. kB.
  16670. Defaults to @samp{"/tmp"}.
  16671. @end deftypevr
  16672. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
  16673. Valid UID range for users. This is mostly to make sure that users can't
  16674. log in as daemons or other system users. Note that denying root logins is
  16675. hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
  16676. is set to 0.
  16677. Defaults to @samp{500}.
  16678. @end deftypevr
  16679. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
  16680. Defaults to @samp{0}.
  16681. @end deftypevr
  16682. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
  16683. Valid GID range for users. Users having non-valid GID as primary group ID
  16684. aren't allowed to log in. If user belongs to supplementary groups with
  16685. non-valid GIDs, those groups are not set.
  16686. Defaults to @samp{1}.
  16687. @end deftypevr
  16688. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
  16689. Defaults to @samp{0}.
  16690. @end deftypevr
  16691. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
  16692. Maximum allowed length for mail keyword name. It's only forced when
  16693. trying to create new keywords.
  16694. Defaults to @samp{50}.
  16695. @end deftypevr
  16696. @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
  16697. List of directories under which chrooting is allowed for mail
  16698. processes (i.e.@: @file{/var/mail} will allow chrooting to @file{/var/mail/foo/bar}
  16699. too). This setting doesn't affect @samp{login-chroot}
  16700. @samp{mail-chroot} or auth chroot settings. If this setting is empty,
  16701. @samp{/./} in home dirs are ignored. WARNING: Never add directories here
  16702. which local users can modify, that may lead to root exploit. Usually
  16703. this should be done only if you don't allow shell access for users.
  16704. <doc/wiki/Chrooting.txt>.
  16705. Defaults to @samp{()}.
  16706. @end deftypevr
  16707. @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
  16708. Default chroot directory for mail processes. This can be overridden
  16709. for specific users in user database by giving @samp{/./} in user's home
  16710. directory (e.g.@: @samp{/home/./user} chroots into @file{/home}). Note that usually
  16711. there is no real need to do chrooting, Dovecot doesn't allow users to
  16712. access files outside their mail directory anyway. If your home
  16713. directories are prefixed with the chroot directory, append @samp{/.} to
  16714. @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
  16715. Defaults to @samp{""}.
  16716. @end deftypevr
  16717. @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
  16718. UNIX socket path to master authentication server to find users.
  16719. This is used by imap (for shared users) and lda.
  16720. Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
  16721. @end deftypevr
  16722. @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
  16723. Directory where to look up mail plugins.
  16724. Defaults to @samp{"/usr/lib/dovecot"}.
  16725. @end deftypevr
  16726. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
  16727. List of plugins to load for all services. Plugins specific to IMAP,
  16728. LDA, etc.@: are added to this list in their own .conf files.
  16729. Defaults to @samp{()}.
  16730. @end deftypevr
  16731. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
  16732. The minimum number of mails in a mailbox before updates are done to
  16733. cache file. This allows optimizing Dovecot's behavior to do less disk
  16734. writes at the cost of more disk reads.
  16735. Defaults to @samp{0}.
  16736. @end deftypevr
  16737. @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
  16738. When IDLE command is running, mailbox is checked once in a while to
  16739. see if there are any new mails or other changes. This setting defines
  16740. the minimum time to wait between those checks. Dovecot can also use
  16741. dnotify, inotify and kqueue to find out immediately when changes
  16742. occur.
  16743. Defaults to @samp{"30 secs"}.
  16744. @end deftypevr
  16745. @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
  16746. Save mails with CR+LF instead of plain LF@. This makes sending those
  16747. mails take less CPU, especially with sendfile() syscall with Linux and
  16748. FreeBSD@. But it also creates a bit more disk I/O which may just make it
  16749. slower. Also note that if other software reads the mboxes/maildirs,
  16750. they may handle the extra CRs wrong and cause problems.
  16751. Defaults to @samp{#f}.
  16752. @end deftypevr
  16753. @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
  16754. By default LIST command returns all entries in maildir beginning
  16755. with a dot. Enabling this option makes Dovecot return only entries
  16756. which are directories. This is done by stat()ing each entry, so it
  16757. causes more disk I/O.
  16758. (For systems setting struct @samp{dirent->d_type} this check is free
  16759. and it's done always regardless of this setting).
  16760. Defaults to @samp{#f}.
  16761. @end deftypevr
  16762. @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
  16763. When copying a message, do it with hard links whenever possible.
  16764. This makes the performance much better, and it's unlikely to have any
  16765. side effects.
  16766. Defaults to @samp{#t}.
  16767. @end deftypevr
  16768. @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
  16769. Assume Dovecot is the only MUA accessing Maildir: Scan cur/
  16770. directory only when its mtime changes unexpectedly or when we can't find
  16771. the mail otherwise.
  16772. Defaults to @samp{#f}.
  16773. @end deftypevr
  16774. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
  16775. Which locking methods to use for locking mbox. There are four
  16776. available:
  16777. @table @code
  16778. @item dotlock
  16779. Create <mailbox>.lock file. This is the oldest and most NFS-safe
  16780. solution. If you want to use /var/mail/ like directory, the users will
  16781. need write access to that directory.
  16782. @item dotlock-try
  16783. Same as dotlock, but if it fails because of permissions or because there
  16784. isn't enough disk space, just skip it.
  16785. @item fcntl
  16786. Use this if possible. Works with NFS too if lockd is used.
  16787. @item flock
  16788. May not exist in all systems. Doesn't work with NFS.
  16789. @item lockf
  16790. May not exist in all systems. Doesn't work with NFS.
  16791. @end table
  16792. You can use multiple locking methods; if you do the order they're declared
  16793. in is important to avoid deadlocks if other MTAs/MUAs are using multiple
  16794. locking methods as well. Some operating systems don't allow using some of
  16795. them simultaneously.
  16796. @end deftypevr
  16797. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
  16798. @end deftypevr
  16799. @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
  16800. Maximum time to wait for lock (all of them) before aborting.
  16801. Defaults to @samp{"5 mins"}.
  16802. @end deftypevr
  16803. @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
  16804. If dotlock exists but the mailbox isn't modified in any way,
  16805. override the lock file after this much time.
  16806. Defaults to @samp{"2 mins"}.
  16807. @end deftypevr
  16808. @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
  16809. When mbox changes unexpectedly we have to fully read it to find out
  16810. what changed. If the mbox is large this can take a long time. Since
  16811. the change is usually just a newly appended mail, it'd be faster to
  16812. simply read the new mails. If this setting is enabled, Dovecot does
  16813. this but still safely fallbacks to re-reading the whole mbox file
  16814. whenever something in mbox isn't how it's expected to be. The only real
  16815. downside to this setting is that if some other MUA changes message
  16816. flags, Dovecot doesn't notice it immediately. Note that a full sync is
  16817. done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
  16818. Defaults to @samp{#t}.
  16819. @end deftypevr
  16820. @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
  16821. Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
  16822. EXAMINE, EXPUNGE or CHECK commands. If this is set,
  16823. @samp{mbox-dirty-syncs} is ignored.
  16824. Defaults to @samp{#f}.
  16825. @end deftypevr
  16826. @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
  16827. Delay writing mbox headers until doing a full write sync (EXPUNGE
  16828. and CHECK commands and when closing the mailbox). This is especially
  16829. useful for POP3 where clients often delete all mails. The downside is
  16830. that our changes aren't immediately visible to other MUAs.
  16831. Defaults to @samp{#t}.
  16832. @end deftypevr
  16833. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
  16834. If mbox size is smaller than this (e.g.@: 100k), don't write index
  16835. files. If an index file already exists it's still read, just not
  16836. updated.
  16837. Defaults to @samp{0}.
  16838. @end deftypevr
  16839. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
  16840. Maximum dbox file size until it's rotated.
  16841. Defaults to @samp{10000000}.
  16842. @end deftypevr
  16843. @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
  16844. Maximum dbox file age until it's rotated. Typically in days. Day
  16845. begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
  16846. disabled.
  16847. Defaults to @samp{"1d"}.
  16848. @end deftypevr
  16849. @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
  16850. When creating new mdbox files, immediately preallocate their size to
  16851. @samp{mdbox-rotate-size}. This setting currently works only in Linux
  16852. with some file systems (ext4, xfs).
  16853. Defaults to @samp{#f}.
  16854. @end deftypevr
  16855. @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
  16856. sdbox and mdbox support saving mail attachments to external files,
  16857. which also allows single instance storage for them. Other backends
  16858. don't support this for now.
  16859. WARNING: This feature hasn't been tested much yet. Use at your own risk.
  16860. Directory root where to store mail attachments. Disabled, if empty.
  16861. Defaults to @samp{""}.
  16862. @end deftypevr
  16863. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
  16864. Attachments smaller than this aren't saved externally. It's also
  16865. possible to write a plugin to disable saving specific attachments
  16866. externally.
  16867. Defaults to @samp{128000}.
  16868. @end deftypevr
  16869. @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
  16870. File system backend to use for saving attachments:
  16871. @table @code
  16872. @item posix
  16873. No SiS done by Dovecot (but this might help FS's own deduplication)
  16874. @item sis posix
  16875. SiS with immediate byte-by-byte comparison during saving
  16876. @item sis-queue posix
  16877. SiS with delayed comparison and deduplication.
  16878. @end table
  16879. Defaults to @samp{"sis posix"}.
  16880. @end deftypevr
  16881. @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
  16882. Hash format to use in attachment filenames. You can add any text and
  16883. variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
  16884. @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
  16885. truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
  16886. Defaults to @samp{"%@{sha1@}"}.
  16887. @end deftypevr
  16888. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
  16889. Defaults to @samp{100}.
  16890. @end deftypevr
  16891. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
  16892. Defaults to @samp{1000}.
  16893. @end deftypevr
  16894. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
  16895. Default VSZ (virtual memory size) limit for service processes.
  16896. This is mainly intended to catch and kill processes that leak memory
  16897. before they eat up everything.
  16898. Defaults to @samp{256000000}.
  16899. @end deftypevr
  16900. @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
  16901. Login user is internally used by login processes. This is the most
  16902. untrusted user in Dovecot system. It shouldn't have access to anything
  16903. at all.
  16904. Defaults to @samp{"dovenull"}.
  16905. @end deftypevr
  16906. @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
  16907. Internal user is used by unprivileged processes. It should be
  16908. separate from login user, so that login processes can't disturb other
  16909. processes.
  16910. Defaults to @samp{"dovecot"}.
  16911. @end deftypevr
  16912. @deftypevr {@code{dovecot-configuration} parameter} string ssl?
  16913. SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
  16914. Defaults to @samp{"required"}.
  16915. @end deftypevr
  16916. @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
  16917. PEM encoded X.509 SSL/TLS certificate (public key).
  16918. Defaults to @samp{"</etc/dovecot/default.pem"}.
  16919. @end deftypevr
  16920. @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
  16921. PEM encoded SSL/TLS private key. The key is opened before
  16922. dropping root privileges, so keep the key file unreadable by anyone but
  16923. root.
  16924. Defaults to @samp{"</etc/dovecot/private/default.pem"}.
  16925. @end deftypevr
  16926. @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
  16927. If key file is password protected, give the password here.
  16928. Alternatively give it when starting dovecot with -p parameter. Since
  16929. this file is often world-readable, you may want to place this setting
  16930. instead to a different.
  16931. Defaults to @samp{""}.
  16932. @end deftypevr
  16933. @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
  16934. PEM encoded trusted certificate authority. Set this only if you
  16935. intend to use @samp{ssl-verify-client-cert? #t}. The file should
  16936. contain the CA certificate(s) followed by the matching
  16937. CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
  16938. Defaults to @samp{""}.
  16939. @end deftypevr
  16940. @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
  16941. Require that CRL check succeeds for client certificates.
  16942. Defaults to @samp{#t}.
  16943. @end deftypevr
  16944. @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
  16945. Request client to send a certificate. If you also want to require
  16946. it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
  16947. Defaults to @samp{#f}.
  16948. @end deftypevr
  16949. @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
  16950. Which field from certificate to use for username. commonName and
  16951. x500UniqueIdentifier are the usual choices. You'll also need to set
  16952. @samp{auth-ssl-username-from-cert? #t}.
  16953. Defaults to @samp{"commonName"}.
  16954. @end deftypevr
  16955. @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
  16956. Minimum SSL protocol version to accept.
  16957. Defaults to @samp{"TLSv1"}.
  16958. @end deftypevr
  16959. @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
  16960. SSL ciphers to use.
  16961. Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
  16962. @end deftypevr
  16963. @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
  16964. SSL crypto device to use, for valid values run "openssl engine".
  16965. Defaults to @samp{""}.
  16966. @end deftypevr
  16967. @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
  16968. Address to use when sending rejection mails.
  16969. %d expands to recipient domain.
  16970. Defaults to @samp{"postmaster@@%d"}.
  16971. @end deftypevr
  16972. @deftypevr {@code{dovecot-configuration} parameter} string hostname
  16973. Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
  16974. and in LMTP replies. Default is the system's real hostname@@domain.
  16975. Defaults to @samp{""}.
  16976. @end deftypevr
  16977. @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
  16978. If user is over quota, return with temporary failure instead of
  16979. bouncing the mail.
  16980. Defaults to @samp{#f}.
  16981. @end deftypevr
  16982. @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
  16983. Binary to use for sending mails.
  16984. Defaults to @samp{"/usr/sbin/sendmail"}.
  16985. @end deftypevr
  16986. @deftypevr {@code{dovecot-configuration} parameter} string submission-host
  16987. If non-empty, send mails via this SMTP host[:port] instead of
  16988. sendmail.
  16989. Defaults to @samp{""}.
  16990. @end deftypevr
  16991. @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
  16992. Subject: header to use for rejection mails. You can use the same
  16993. variables as for @samp{rejection-reason} below.
  16994. Defaults to @samp{"Rejected: %s"}.
  16995. @end deftypevr
  16996. @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
  16997. Human readable error message for rejection mails. You can use
  16998. variables:
  16999. @table @code
  17000. @item %n
  17001. CRLF
  17002. @item %r
  17003. reason
  17004. @item %s
  17005. original subject
  17006. @item %t
  17007. recipient
  17008. @end table
  17009. Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
  17010. @end deftypevr
  17011. @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
  17012. Delimiter character between local-part and detail in email
  17013. address.
  17014. Defaults to @samp{"+"}.
  17015. @end deftypevr
  17016. @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
  17017. Header where the original recipient address (SMTP's RCPT TO:
  17018. address) is taken from if not available elsewhere. With dovecot-lda -a
  17019. parameter overrides this. A commonly used header for this is
  17020. X-Original-To.
  17021. Defaults to @samp{""}.
  17022. @end deftypevr
  17023. @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
  17024. Should saving a mail to a nonexistent mailbox automatically create
  17025. it?.
  17026. Defaults to @samp{#f}.
  17027. @end deftypevr
  17028. @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
  17029. Should automatically created mailboxes be also automatically
  17030. subscribed?.
  17031. Defaults to @samp{#f}.
  17032. @end deftypevr
  17033. @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
  17034. Maximum IMAP command line length. Some clients generate very long
  17035. command lines with huge mailboxes, so you may need to raise this if you
  17036. get "Too long argument" or "IMAP command line too large" errors
  17037. often.
  17038. Defaults to @samp{64000}.
  17039. @end deftypevr
  17040. @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
  17041. IMAP logout format string:
  17042. @table @code
  17043. @item %i
  17044. total number of bytes read from client
  17045. @item %o
  17046. total number of bytes sent to client.
  17047. @end table
  17048. See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
  17049. 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@}"}.
  17050. @end deftypevr
  17051. @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
  17052. Override the IMAP CAPABILITY response. If the value begins with '+',
  17053. add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
  17054. Defaults to @samp{""}.
  17055. @end deftypevr
  17056. @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
  17057. How long to wait between "OK Still here" notifications when client
  17058. is IDLEing.
  17059. Defaults to @samp{"2 mins"}.
  17060. @end deftypevr
  17061. @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
  17062. ID field names and values to send to clients. Using * as the value
  17063. makes Dovecot use the default value. The following fields have default
  17064. values currently: name, version, os, os-version, support-url,
  17065. support-email.
  17066. Defaults to @samp{""}.
  17067. @end deftypevr
  17068. @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
  17069. ID fields sent by client to log. * means everything.
  17070. Defaults to @samp{""}.
  17071. @end deftypevr
  17072. @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
  17073. Workarounds for various client bugs:
  17074. @table @code
  17075. @item delay-newmail
  17076. Send EXISTS/RECENT new mail notifications only when replying to NOOP and
  17077. CHECK commands. Some clients ignore them otherwise, for example OSX
  17078. Mail (<v2.1). Outlook Express breaks more badly though, without this it
  17079. may show user "Message no longer in server" errors. Note that OE6
  17080. still breaks even with this workaround if synchronization is set to
  17081. "Headers Only".
  17082. @item tb-extra-mailbox-sep
  17083. Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
  17084. adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
  17085. ignore the extra @samp{/} instead of treating it as invalid mailbox name.
  17086. @item tb-lsub-flags
  17087. Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
  17088. This makes Thunderbird realize they aren't selectable and show them
  17089. greyed out, instead of only later giving "not selectable" popup error.
  17090. @end table
  17091. Defaults to @samp{()}.
  17092. @end deftypevr
  17093. @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
  17094. Host allowed in URLAUTH URLs sent by client. "*" allows all.
  17095. Defaults to @samp{""}.
  17096. @end deftypevr
  17097. Whew! Lots of configuration options. The nice thing about it though is
  17098. that Guix has a complete interface to Dovecot's configuration
  17099. language. This allows not only a nice way to declare configurations,
  17100. but also offers reflective capabilities as well: users can write code to
  17101. inspect and transform configurations from within Scheme.
  17102. However, it could be that you just want to get a @code{dovecot.conf} up
  17103. and running. In that case, you can pass an
  17104. @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
  17105. @code{dovecot-service}. As its name indicates, an opaque configuration
  17106. does not have easy reflective capabilities.
  17107. Available @code{opaque-dovecot-configuration} fields are:
  17108. @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
  17109. The dovecot package.
  17110. @end deftypevr
  17111. @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
  17112. The contents of the @code{dovecot.conf}, as a string.
  17113. @end deftypevr
  17114. For example, if your @code{dovecot.conf} is just the empty string, you
  17115. could instantiate a dovecot service like this:
  17116. @lisp
  17117. (dovecot-service #:config
  17118. (opaque-dovecot-configuration
  17119. (string "")))
  17120. @end lisp
  17121. @subsubheading OpenSMTPD Service
  17122. @deffn {Scheme Variable} opensmtpd-service-type
  17123. This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
  17124. service, whose value should be an @code{opensmtpd-configuration} object
  17125. as in this example:
  17126. @lisp
  17127. (service opensmtpd-service-type
  17128. (opensmtpd-configuration
  17129. (config-file (local-file "./my-smtpd.conf"))))
  17130. @end lisp
  17131. @end deffn
  17132. @deftp {Data Type} opensmtpd-configuration
  17133. Data type representing the configuration of opensmtpd.
  17134. @table @asis
  17135. @item @code{package} (default: @var{opensmtpd})
  17136. Package object of the OpenSMTPD SMTP server.
  17137. @item @code{config-file} (default: @code{%default-opensmtpd-file})
  17138. File-like object of the OpenSMTPD configuration file to use. By default
  17139. it listens on the loopback network interface, and allows for mail from
  17140. users and daemons on the local machine, as well as permitting email to
  17141. remote servers. Run @command{man smtpd.conf} for more information.
  17142. @end table
  17143. @end deftp
  17144. @subsubheading Exim Service
  17145. @cindex mail transfer agent (MTA)
  17146. @cindex MTA (mail transfer agent)
  17147. @cindex SMTP
  17148. @deffn {Scheme Variable} exim-service-type
  17149. This is the type of the @uref{https://exim.org, Exim} mail transfer
  17150. agent (MTA), whose value should be an @code{exim-configuration} object
  17151. as in this example:
  17152. @lisp
  17153. (service exim-service-type
  17154. (exim-configuration
  17155. (config-file (local-file "./my-exim.conf"))))
  17156. @end lisp
  17157. @end deffn
  17158. In order to use an @code{exim-service-type} service you must also have a
  17159. @code{mail-aliases-service-type} service present in your
  17160. @code{operating-system} (even if it has no aliases).
  17161. @deftp {Data Type} exim-configuration
  17162. Data type representing the configuration of exim.
  17163. @table @asis
  17164. @item @code{package} (default: @var{exim})
  17165. Package object of the Exim server.
  17166. @item @code{config-file} (default: @code{#f})
  17167. File-like object of the Exim configuration file to use. If its value is
  17168. @code{#f} then use the default configuration file from the package
  17169. provided in @code{package}. The resulting configuration file is loaded
  17170. after setting the @code{exim_user} and @code{exim_group} configuration
  17171. variables.
  17172. @end table
  17173. @end deftp
  17174. @subsubheading Getmail service
  17175. @cindex IMAP
  17176. @cindex POP
  17177. @deffn {Scheme Variable} getmail-service-type
  17178. This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
  17179. mail retriever, whose value should be an @code{getmail-configuration}.
  17180. @end deffn
  17181. Available @code{getmail-configuration} fields are:
  17182. @deftypevr {@code{getmail-configuration} parameter} symbol name
  17183. A symbol to identify the getmail service.
  17184. Defaults to @samp{"unset"}.
  17185. @end deftypevr
  17186. @deftypevr {@code{getmail-configuration} parameter} package package
  17187. The getmail package to use.
  17188. @end deftypevr
  17189. @deftypevr {@code{getmail-configuration} parameter} string user
  17190. The user to run getmail as.
  17191. Defaults to @samp{"getmail"}.
  17192. @end deftypevr
  17193. @deftypevr {@code{getmail-configuration} parameter} string group
  17194. The group to run getmail as.
  17195. Defaults to @samp{"getmail"}.
  17196. @end deftypevr
  17197. @deftypevr {@code{getmail-configuration} parameter} string directory
  17198. The getmail directory to use.
  17199. Defaults to @samp{"/var/lib/getmail/default"}.
  17200. @end deftypevr
  17201. @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
  17202. The getmail configuration file to use.
  17203. Available @code{getmail-configuration-file} fields are:
  17204. @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
  17205. What mail account to retrieve mail from, and how to access that account.
  17206. Available @code{getmail-retriever-configuration} fields are:
  17207. @deftypevr {@code{getmail-retriever-configuration} parameter} string type
  17208. The type of mail retriever to use. Valid values include @samp{passwd}
  17209. and @samp{static}.
  17210. Defaults to @samp{"SimpleIMAPSSLRetriever"}.
  17211. @end deftypevr
  17212. @deftypevr {@code{getmail-retriever-configuration} parameter} string server
  17213. Username to login to the mail server with.
  17214. Defaults to @samp{unset}.
  17215. @end deftypevr
  17216. @deftypevr {@code{getmail-retriever-configuration} parameter} string username
  17217. Username to login to the mail server with.
  17218. Defaults to @samp{unset}.
  17219. @end deftypevr
  17220. @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
  17221. Port number to connect to.
  17222. Defaults to @samp{#f}.
  17223. @end deftypevr
  17224. @deftypevr {@code{getmail-retriever-configuration} parameter} string password
  17225. Override fields from passwd.
  17226. Defaults to @samp{""}.
  17227. @end deftypevr
  17228. @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
  17229. Override fields from passwd.
  17230. Defaults to @samp{()}.
  17231. @end deftypevr
  17232. @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
  17233. PEM-formatted key file to use for the TLS negotiation.
  17234. Defaults to @samp{""}.
  17235. @end deftypevr
  17236. @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
  17237. PEM-formatted certificate file to use for the TLS negotiation.
  17238. Defaults to @samp{""}.
  17239. @end deftypevr
  17240. @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
  17241. CA certificates to use.
  17242. Defaults to @samp{""}.
  17243. @end deftypevr
  17244. @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
  17245. Extra retriever parameters.
  17246. Defaults to @samp{()}.
  17247. @end deftypevr
  17248. @end deftypevr
  17249. @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
  17250. What to do with retrieved messages.
  17251. Available @code{getmail-destination-configuration} fields are:
  17252. @deftypevr {@code{getmail-destination-configuration} parameter} string type
  17253. The type of mail destination. Valid values include @samp{Maildir},
  17254. @samp{Mboxrd} and @samp{MDA_external}.
  17255. Defaults to @samp{unset}.
  17256. @end deftypevr
  17257. @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
  17258. The path option for the mail destination. The behaviour depends on the
  17259. chosen type.
  17260. Defaults to @samp{""}.
  17261. @end deftypevr
  17262. @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
  17263. Extra destination parameters
  17264. Defaults to @samp{()}.
  17265. @end deftypevr
  17266. @end deftypevr
  17267. @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
  17268. Configure getmail.
  17269. Available @code{getmail-options-configuration} fields are:
  17270. @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
  17271. If set to @samp{0}, getmail will only print warnings and errors. A
  17272. value of @samp{1} means that messages will be printed about retrieving
  17273. and deleting messages. If set to @samp{2}, getmail will print messages
  17274. about each of it's actions.
  17275. Defaults to @samp{1}.
  17276. @end deftypevr
  17277. @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
  17278. If true, getmail will retrieve all available messages. Otherwise it
  17279. will only retrieve messages it hasn't seen previously.
  17280. Defaults to @samp{#t}.
  17281. @end deftypevr
  17282. @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
  17283. If set to true, messages will be deleted from the server after
  17284. retrieving and successfully delivering them. Otherwise, messages will
  17285. be left on the server.
  17286. Defaults to @samp{#f}.
  17287. @end deftypevr
  17288. @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
  17289. Getmail will delete messages this number of days after seeing them, if
  17290. they have been delivered. This means messages will be left on the
  17291. server this number of days after delivering them. A value of @samp{0}
  17292. disabled this feature.
  17293. Defaults to @samp{0}.
  17294. @end deftypevr
  17295. @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
  17296. Delete messages larger than this of bytes after retrieving them, even if
  17297. the delete and delete-after options are disabled. A value of @samp{0}
  17298. disables this feature.
  17299. Defaults to @samp{0}.
  17300. @end deftypevr
  17301. @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
  17302. Retrieve messages totalling up to this number of bytes before closing
  17303. the session with the server. A value of @samp{0} disables this feature.
  17304. Defaults to @samp{0}.
  17305. @end deftypevr
  17306. @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
  17307. Don't retrieve messages larger than this number of bytes. A value of
  17308. @samp{0} disables this feature.
  17309. Defaults to @samp{0}.
  17310. @end deftypevr
  17311. @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
  17312. If true, getmail will add a Delivered-To header to messages.
  17313. Defaults to @samp{#t}.
  17314. @end deftypevr
  17315. @deftypevr {@code{getmail-options-configuration} parameter} boolean received
  17316. If set, getmail adds a Received header to the messages.
  17317. Defaults to @samp{#t}.
  17318. @end deftypevr
  17319. @deftypevr {@code{getmail-options-configuration} parameter} string message-log
  17320. Getmail will record a log of its actions to the named file. A value of
  17321. @samp{""} disables this feature.
  17322. Defaults to @samp{""}.
  17323. @end deftypevr
  17324. @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
  17325. If true, getmail will record a log of its actions using the system
  17326. logger.
  17327. Defaults to @samp{#f}.
  17328. @end deftypevr
  17329. @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
  17330. If true, getmail will log information about messages not retrieved and
  17331. the reason for not retrieving them, as well as starting and ending
  17332. information lines.
  17333. Defaults to @samp{#f}.
  17334. @end deftypevr
  17335. @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
  17336. Extra options to include.
  17337. Defaults to @samp{()}.
  17338. @end deftypevr
  17339. @end deftypevr
  17340. @end deftypevr
  17341. @deftypevr {@code{getmail-configuration} parameter} list idle
  17342. A list of mailboxes that getmail should wait on the server for new mail
  17343. notifications. This depends on the server supporting the IDLE
  17344. extension.
  17345. Defaults to @samp{()}.
  17346. @end deftypevr
  17347. @deftypevr {@code{getmail-configuration} parameter} list environment-variables
  17348. Environment variables to set for getmail.
  17349. Defaults to @samp{()}.
  17350. @end deftypevr
  17351. @subsubheading Mail Aliases Service
  17352. @cindex email aliases
  17353. @cindex aliases, for email addresses
  17354. @deffn {Scheme Variable} mail-aliases-service-type
  17355. This is the type of the service which provides @code{/etc/aliases},
  17356. specifying how to deliver mail to users on this system.
  17357. @lisp
  17358. (service mail-aliases-service-type
  17359. '(("postmaster" "bob")
  17360. ("bob" "bob@@example.com" "bob@@example2.com")))
  17361. @end lisp
  17362. @end deffn
  17363. The configuration for a @code{mail-aliases-service-type} service is an
  17364. association list denoting how to deliver mail that comes to this
  17365. system. Each entry is of the form @code{(alias addresses ...)}, with
  17366. @code{alias} specifying the local alias and @code{addresses} specifying
  17367. where to deliver this user's mail.
  17368. The aliases aren't required to exist as users on the local system. In
  17369. the above example, there doesn't need to be a @code{postmaster} entry in
  17370. the @code{operating-system}'s @code{user-accounts} in order to deliver
  17371. the @code{postmaster} mail to @code{bob} (which subsequently would
  17372. deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
  17373. @subsubheading GNU Mailutils IMAP4 Daemon
  17374. @cindex GNU Mailutils IMAP4 Daemon
  17375. @deffn {Scheme Variable} imap4d-service-type
  17376. This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
  17377. mailutils, GNU Mailutils Manual}), whose value should be an
  17378. @code{imap4d-configuration} object as in this example:
  17379. @lisp
  17380. (service imap4d-service-type
  17381. (imap4d-configuration
  17382. (config-file (local-file "imap4d.conf"))))
  17383. @end lisp
  17384. @end deffn
  17385. @deftp {Data Type} imap4d-configuration
  17386. Data type representing the configuration of @command{imap4d}.
  17387. @table @asis
  17388. @item @code{package} (default: @code{mailutils})
  17389. The package that provides @command{imap4d}.
  17390. @item @code{config-file} (default: @code{%default-imap4d-config-file})
  17391. File-like object of the configuration file to use, by default it will listen
  17392. on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
  17393. Mailutils Manual}, for details.
  17394. @end table
  17395. @end deftp
  17396. @subsubheading Radicale Service
  17397. @cindex CalDAV
  17398. @cindex CardDAV
  17399. @deffn {Scheme Variable} radicale-service-type
  17400. This is the type of the @uref{https://radicale.org, Radicale} CalDAV/CardDAV
  17401. server whose value should be a @code{radicale-configuration}.
  17402. @end deffn
  17403. @deftp {Data Type} radicale-configuration
  17404. Data type representing the configuration of @command{radicale}.
  17405. @table @asis
  17406. @item @code{package} (default: @code{radicale})
  17407. The package that provides @command{radicale}.
  17408. @item @code{config-file} (default: @code{%default-radicale-config-file})
  17409. File-like object of the configuration file to use, by default it will listen
  17410. on TCP port 5232 of @code{localhost} and use the @code{htpasswd} file at
  17411. @file{/var/lib/radicale/users} with no (@code{plain}) encryption.
  17412. @end table
  17413. @end deftp
  17414. @node Messaging Services
  17415. @subsection Messaging Services
  17416. @cindex messaging
  17417. @cindex jabber
  17418. @cindex XMPP
  17419. The @code{(gnu services messaging)} module provides Guix service
  17420. definitions for messaging services. Currently it provides the following
  17421. services:
  17422. @subsubheading Prosody Service
  17423. @deffn {Scheme Variable} prosody-service-type
  17424. This is the type for the @uref{https://prosody.im, Prosody XMPP
  17425. communication server}. Its value must be a @code{prosody-configuration}
  17426. record as in this example:
  17427. @lisp
  17428. (service prosody-service-type
  17429. (prosody-configuration
  17430. (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
  17431. (int-components
  17432. (list
  17433. (int-component-configuration
  17434. (hostname "conference.example.net")
  17435. (plugin "muc")
  17436. (mod-muc (mod-muc-configuration)))))
  17437. (virtualhosts
  17438. (list
  17439. (virtualhost-configuration
  17440. (domain "example.net"))))))
  17441. @end lisp
  17442. See below for details about @code{prosody-configuration}.
  17443. @end deffn
  17444. By default, Prosody does not need much configuration. Only one
  17445. @code{virtualhosts} field is needed: it specifies the domain you wish
  17446. Prosody to serve.
  17447. You can perform various sanity checks on the generated configuration
  17448. with the @code{prosodyctl check} command.
  17449. Prosodyctl will also help you to import certificates from the
  17450. @code{letsencrypt} directory so that the @code{prosody} user can access
  17451. them. See @url{https://prosody.im/doc/letsencrypt}.
  17452. @example
  17453. prosodyctl --root cert import /etc/letsencrypt/live
  17454. @end example
  17455. The available configuration parameters follow. Each parameter
  17456. definition is preceded by its type; for example, @samp{string-list foo}
  17457. indicates that the @code{foo} parameter should be specified as a list of
  17458. strings. Types starting with @code{maybe-} denote parameters that won't
  17459. show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
  17460. There is also a way to specify the configuration as a string, if you
  17461. have an old @code{prosody.cfg.lua} file that you want to port over from
  17462. some other system; see the end for more details.
  17463. The @code{file-object} type designates either a file-like object
  17464. (@pxref{G-Expressions, file-like objects}) or a file name.
  17465. @c The following documentation was initially generated by
  17466. @c (generate-documentation) in (gnu services messaging). Manually maintained
  17467. @c documentation is better, so we shouldn't hesitate to edit below as
  17468. @c needed. However if the change you want to make to this documentation
  17469. @c can be done in an automated way, it's probably easier to change
  17470. @c (generate-documentation) than to make it below and have to deal with
  17471. @c the churn as Prosody updates.
  17472. Available @code{prosody-configuration} fields are:
  17473. @deftypevr {@code{prosody-configuration} parameter} package prosody
  17474. The Prosody package.
  17475. @end deftypevr
  17476. @deftypevr {@code{prosody-configuration} parameter} file-name data-path
  17477. Location of the Prosody data storage directory. See
  17478. @url{https://prosody.im/doc/configure}.
  17479. Defaults to @samp{"/var/lib/prosody"}.
  17480. @end deftypevr
  17481. @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
  17482. Additional plugin directories. They are searched in all the specified
  17483. paths in order. See @url{https://prosody.im/doc/plugins_directory}.
  17484. Defaults to @samp{()}.
  17485. @end deftypevr
  17486. @deftypevr {@code{prosody-configuration} parameter} file-name certificates
  17487. Every virtual host and component needs a certificate so that clients and
  17488. servers can securely verify its identity. Prosody will automatically load
  17489. certificates/keys from the directory specified here.
  17490. Defaults to @samp{"/etc/prosody/certs"}.
  17491. @end deftypevr
  17492. @deftypevr {@code{prosody-configuration} parameter} string-list admins
  17493. This is a list of accounts that are admins for the server. Note that you
  17494. must create the accounts separately. See @url{https://prosody.im/doc/admins} and
  17495. @url{https://prosody.im/doc/creating_accounts}.
  17496. Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
  17497. Defaults to @samp{()}.
  17498. @end deftypevr
  17499. @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
  17500. Enable use of libevent for better performance under high load. See
  17501. @url{https://prosody.im/doc/libevent}.
  17502. Defaults to @samp{#f}.
  17503. @end deftypevr
  17504. @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
  17505. This is the list of modules Prosody will load on startup. It looks for
  17506. @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
  17507. Documentation on modules can be found at:
  17508. @url{https://prosody.im/doc/modules}.
  17509. Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
  17510. @end deftypevr
  17511. @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
  17512. @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
  17513. should you want to disable them then add them to this list.
  17514. Defaults to @samp{()}.
  17515. @end deftypevr
  17516. @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
  17517. Path to a text file where the shared groups are defined. If this path is
  17518. empty then @samp{mod_groups} does nothing. See
  17519. @url{https://prosody.im/doc/modules/mod_groups}.
  17520. Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
  17521. @end deftypevr
  17522. @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
  17523. Disable account creation by default, for security. See
  17524. @url{https://prosody.im/doc/creating_accounts}.
  17525. Defaults to @samp{#f}.
  17526. @end deftypevr
  17527. @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
  17528. These are the SSL/TLS-related settings. Most of them are disabled so to
  17529. use Prosody's defaults. If you do not completely understand these options, do
  17530. not add them to your config, it is easy to lower the security of your server
  17531. using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
  17532. Available @code{ssl-configuration} fields are:
  17533. @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
  17534. This determines what handshake to use.
  17535. @end deftypevr
  17536. @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
  17537. Path to your private key file.
  17538. @end deftypevr
  17539. @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
  17540. Path to your certificate file.
  17541. @end deftypevr
  17542. @deftypevr {@code{ssl-configuration} parameter} file-object capath
  17543. Path to directory containing root certificates that you wish Prosody to
  17544. trust when verifying the certificates of remote servers.
  17545. Defaults to @samp{"/etc/ssl/certs"}.
  17546. @end deftypevr
  17547. @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
  17548. Path to a file containing root certificates that you wish Prosody to trust.
  17549. Similar to @code{capath} but with all certificates concatenated together.
  17550. @end deftypevr
  17551. @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
  17552. A list of verification options (these mostly map to OpenSSL's
  17553. @code{set_verify()} flags).
  17554. @end deftypevr
  17555. @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
  17556. A list of general options relating to SSL/TLS@. These map to OpenSSL's
  17557. @code{set_options()}. For a full list of options available in LuaSec, see the
  17558. LuaSec source.
  17559. @end deftypevr
  17560. @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
  17561. How long a chain of certificate authorities to check when looking for a
  17562. trusted root certificate.
  17563. @end deftypevr
  17564. @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
  17565. An OpenSSL cipher string. This selects what ciphers Prosody will offer to
  17566. clients, and in what order.
  17567. @end deftypevr
  17568. @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
  17569. A path to a file containing parameters for Diffie-Hellman key exchange. You
  17570. can create such a file with:
  17571. @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
  17572. @end deftypevr
  17573. @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
  17574. Curve for Elliptic curve Diffie-Hellman. Prosody's default is
  17575. @samp{"secp384r1"}.
  17576. @end deftypevr
  17577. @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
  17578. A list of ``extra'' verification options.
  17579. @end deftypevr
  17580. @deftypevr {@code{ssl-configuration} parameter} maybe-string password
  17581. Password for encrypted private keys.
  17582. @end deftypevr
  17583. @end deftypevr
  17584. @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
  17585. Whether to force all client-to-server connections to be encrypted or not.
  17586. See @url{https://prosody.im/doc/modules/mod_tls}.
  17587. Defaults to @samp{#f}.
  17588. @end deftypevr
  17589. @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
  17590. Set of mechanisms that will never be offered. See
  17591. @url{https://prosody.im/doc/modules/mod_saslauth}.
  17592. Defaults to @samp{("DIGEST-MD5")}.
  17593. @end deftypevr
  17594. @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
  17595. Whether to force all server-to-server connections to be encrypted or not.
  17596. See @url{https://prosody.im/doc/modules/mod_tls}.
  17597. Defaults to @samp{#f}.
  17598. @end deftypevr
  17599. @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
  17600. Whether to require encryption and certificate authentication. This
  17601. provides ideal security, but requires servers you communicate with to support
  17602. encryption AND present valid, trusted certificates. See
  17603. @url{https://prosody.im/doc/s2s#security}.
  17604. Defaults to @samp{#f}.
  17605. @end deftypevr
  17606. @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
  17607. Many servers don't support encryption or have invalid or self-signed
  17608. certificates. You can list domains here that will not be required to
  17609. authenticate using certificates. They will be authenticated using DNS@. See
  17610. @url{https://prosody.im/doc/s2s#security}.
  17611. Defaults to @samp{()}.
  17612. @end deftypevr
  17613. @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
  17614. Even if you leave @code{s2s-secure-auth?} disabled, you can still require
  17615. valid certificates for some domains by specifying a list here. See
  17616. @url{https://prosody.im/doc/s2s#security}.
  17617. Defaults to @samp{()}.
  17618. @end deftypevr
  17619. @deftypevr {@code{prosody-configuration} parameter} string authentication
  17620. Select the authentication backend to use. The default provider stores
  17621. passwords in plaintext and uses Prosody's configured data storage to store the
  17622. authentication data. If you do not trust your server please see
  17623. @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
  17624. about using the hashed backend. See also
  17625. @url{https://prosody.im/doc/authentication}
  17626. Defaults to @samp{"internal_plain"}.
  17627. @end deftypevr
  17628. @deftypevr {@code{prosody-configuration} parameter} maybe-string log
  17629. Set logging options. Advanced logging configuration is not yet supported
  17630. by the Prosody service. See @url{https://prosody.im/doc/logging}.
  17631. Defaults to @samp{"*syslog"}.
  17632. @end deftypevr
  17633. @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
  17634. File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
  17635. Defaults to @samp{"/var/run/prosody/prosody.pid"}.
  17636. @end deftypevr
  17637. @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
  17638. Maximum allowed size of the HTTP body (in bytes).
  17639. @end deftypevr
  17640. @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
  17641. Some modules expose their own URL in various ways. This URL is built
  17642. from the protocol, host and port used. If Prosody sits behind a proxy, the
  17643. public URL will be @code{http-external-url} instead. See
  17644. @url{https://prosody.im/doc/http#external_url}.
  17645. @end deftypevr
  17646. @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
  17647. A host in Prosody is a domain on which user accounts can be created. For
  17648. example if you want your users to have addresses like
  17649. @samp{"john.smith@@example.com"} then you need to add a host
  17650. @samp{"example.com"}. All options in this list will apply only to this host.
  17651. Note: the name @emph{virtual} host is used in configuration to avoid confusion with
  17652. the actual physical host that Prosody is installed on. A single Prosody
  17653. instance can serve many domains, each one defined as a VirtualHost entry in
  17654. Prosody's configuration. Conversely a server that hosts a single domain would
  17655. have just one VirtualHost entry.
  17656. See @url{https://prosody.im/doc/configure#virtual_host_settings}.
  17657. Available @code{virtualhost-configuration} fields are:
  17658. 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:
  17659. @deftypevr {@code{virtualhost-configuration} parameter} string domain
  17660. Domain you wish Prosody to serve.
  17661. @end deftypevr
  17662. @end deftypevr
  17663. @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
  17664. Components are extra services on a server which are available to clients,
  17665. usually on a subdomain of the main server (such as
  17666. @samp{"mycomponent.example.com"}). Example components might be chatroom
  17667. servers, user directories, or gateways to other protocols.
  17668. Internal components are implemented with Prosody-specific plugins. To add an
  17669. internal component, you simply fill the hostname field, and the plugin you wish
  17670. to use for the component.
  17671. See @url{https://prosody.im/doc/components}.
  17672. Defaults to @samp{()}.
  17673. Available @code{int-component-configuration} fields are:
  17674. 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:
  17675. @deftypevr {@code{int-component-configuration} parameter} string hostname
  17676. Hostname of the component.
  17677. @end deftypevr
  17678. @deftypevr {@code{int-component-configuration} parameter} string plugin
  17679. Plugin you wish to use for the component.
  17680. @end deftypevr
  17681. @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
  17682. Multi-user chat (MUC) is Prosody's module for allowing you to create
  17683. hosted chatrooms/conferences for XMPP users.
  17684. General information on setting up and using multi-user chatrooms can be found
  17685. in the ``Chatrooms'' documentation (@url{https://prosody.im/doc/chatrooms}),
  17686. which you should read if you are new to XMPP chatrooms.
  17687. See also @url{https://prosody.im/doc/modules/mod_muc}.
  17688. Available @code{mod-muc-configuration} fields are:
  17689. @deftypevr {@code{mod-muc-configuration} parameter} string name
  17690. The name to return in service discovery responses.
  17691. Defaults to @samp{"Prosody Chatrooms"}.
  17692. @end deftypevr
  17693. @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
  17694. If @samp{#t}, this will only allow admins to create new chatrooms.
  17695. Otherwise anyone can create a room. The value @samp{"local"} restricts room
  17696. creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
  17697. can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
  17698. restricts to service administrators only.
  17699. Defaults to @samp{#f}.
  17700. @end deftypevr
  17701. @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
  17702. Maximum number of history messages that will be sent to the member that has
  17703. just joined the room.
  17704. Defaults to @samp{20}.
  17705. @end deftypevr
  17706. @end deftypevr
  17707. @end deftypevr
  17708. @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
  17709. External components use XEP-0114, which most standalone components
  17710. support. To add an external component, you simply fill the hostname field. See
  17711. @url{https://prosody.im/doc/components}.
  17712. Defaults to @samp{()}.
  17713. Available @code{ext-component-configuration} fields are:
  17714. 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:
  17715. @deftypevr {@code{ext-component-configuration} parameter} string component-secret
  17716. Password which the component will use to log in.
  17717. @end deftypevr
  17718. @deftypevr {@code{ext-component-configuration} parameter} string hostname
  17719. Hostname of the component.
  17720. @end deftypevr
  17721. @end deftypevr
  17722. @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
  17723. Port(s) Prosody listens on for component connections.
  17724. Defaults to @samp{(5347)}.
  17725. @end deftypevr
  17726. @deftypevr {@code{prosody-configuration} parameter} string component-interface
  17727. Interface Prosody listens on for component connections.
  17728. Defaults to @samp{"127.0.0.1"}.
  17729. @end deftypevr
  17730. @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
  17731. Raw content that will be added to the configuration file.
  17732. @end deftypevr
  17733. It could be that you just want to get a @code{prosody.cfg.lua}
  17734. up and running. In that case, you can pass an
  17735. @code{opaque-prosody-configuration} record as the value of
  17736. @code{prosody-service-type}. As its name indicates, an opaque configuration
  17737. does not have easy reflective capabilities.
  17738. Available @code{opaque-prosody-configuration} fields are:
  17739. @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
  17740. The prosody package.
  17741. @end deftypevr
  17742. @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
  17743. The contents of the @code{prosody.cfg.lua} to use.
  17744. @end deftypevr
  17745. For example, if your @code{prosody.cfg.lua} is just the empty
  17746. string, you could instantiate a prosody service like this:
  17747. @lisp
  17748. (service prosody-service-type
  17749. (opaque-prosody-configuration
  17750. (prosody.cfg.lua "")))
  17751. @end lisp
  17752. @c end of Prosody auto-generated documentation
  17753. @subsubheading BitlBee Service
  17754. @cindex IRC (Internet Relay Chat)
  17755. @cindex IRC gateway
  17756. @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
  17757. interface to a variety of messaging protocols such as XMPP.
  17758. @defvr {Scheme Variable} bitlbee-service-type
  17759. This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
  17760. gateway daemon. Its value is a @code{bitlbee-configuration} (see
  17761. below).
  17762. To have BitlBee listen on port 6667 on localhost, add this line to your
  17763. services:
  17764. @lisp
  17765. (service bitlbee-service-type)
  17766. @end lisp
  17767. @end defvr
  17768. @deftp {Data Type} bitlbee-configuration
  17769. This is the configuration for BitlBee, with the following fields:
  17770. @table @asis
  17771. @item @code{interface} (default: @code{"127.0.0.1"})
  17772. @itemx @code{port} (default: @code{6667})
  17773. Listen on the network interface corresponding to the IP address
  17774. specified in @var{interface}, on @var{port}.
  17775. When @var{interface} is @code{127.0.0.1}, only local clients can
  17776. connect; when it is @code{0.0.0.0}, connections can come from any
  17777. networking interface.
  17778. @item @code{bitlbee} (default: @code{bitlbee})
  17779. The BitlBee package to use.
  17780. @item @code{plugins} (default: @code{'()})
  17781. List of plugin packages to use---e.g., @code{bitlbee-discord}.
  17782. @item @code{extra-settings} (default: @code{""})
  17783. Configuration snippet added as-is to the BitlBee configuration file.
  17784. @end table
  17785. @end deftp
  17786. @subsubheading Quassel Service
  17787. @cindex IRC (Internet Relay Chat)
  17788. @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
  17789. meaning that one or more clients can attach to and detach from the
  17790. central core.
  17791. @defvr {Scheme Variable} quassel-service-type
  17792. This is the service type for the @url{https://quassel-irc.org/,Quassel}
  17793. IRC backend daemon. Its value is a @code{quassel-configuration}
  17794. (see below).
  17795. @end defvr
  17796. @deftp {Data Type} quassel-configuration
  17797. This is the configuration for Quassel, with the following fields:
  17798. @table @asis
  17799. @item @code{quassel} (default: @code{quassel})
  17800. The Quassel package to use.
  17801. @item @code{interface} (default: @code{"::,0.0.0.0"})
  17802. @item @code{port} (default: @code{4242})
  17803. Listen on the network interface(s) corresponding to the IPv4 or IPv6
  17804. interfaces specified in the comma delimited @var{interface}, on
  17805. @var{port}.
  17806. @item @code{loglevel} (default: @code{"Info"})
  17807. The level of logging desired. Accepted values are Debug, Info, Warning
  17808. and Error.
  17809. @end table
  17810. @end deftp
  17811. @node Telephony Services
  17812. @subsection Telephony Services
  17813. @cindex Murmur (VoIP server)
  17814. @cindex VoIP server
  17815. This section describes how to set up and run a Murmur server. Murmur is
  17816. the server of the @uref{https://mumble.info, Mumble} voice-over-IP
  17817. (VoIP) suite.
  17818. @deftp {Data Type} murmur-configuration
  17819. The service type for the Murmur server. An example configuration can
  17820. look like this:
  17821. @lisp
  17822. (service murmur-service-type
  17823. (murmur-configuration
  17824. (welcome-text
  17825. "Welcome to this Mumble server running on Guix!")
  17826. (cert-required? #t) ;disallow text password logins
  17827. (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
  17828. (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
  17829. @end lisp
  17830. After reconfiguring your system, you can manually set the murmur @code{SuperUser}
  17831. password with the command that is printed during the activation phase.
  17832. It is recommended to register a normal Mumble user account
  17833. and grant it admin or moderator rights.
  17834. You can use the @code{mumble} client to
  17835. login as new normal user, register yourself, and log out.
  17836. For the next step login with the name @code{SuperUser} use
  17837. the @code{SuperUser} password that you set previously,
  17838. and grant your newly registered mumble user administrator or moderator
  17839. rights and create some channels.
  17840. Available @code{murmur-configuration} fields are:
  17841. @table @asis
  17842. @item @code{package} (default: @code{mumble})
  17843. Package that contains @code{bin/murmurd}.
  17844. @item @code{user} (default: @code{"murmur"})
  17845. User who will run the Murmur server.
  17846. @item @code{group} (default: @code{"murmur"})
  17847. Group of the user who will run the murmur server.
  17848. @item @code{port} (default: @code{64738})
  17849. Port on which the server will listen.
  17850. @item @code{welcome-text} (default: @code{""})
  17851. Welcome text sent to clients when they connect.
  17852. @item @code{server-password} (default: @code{""})
  17853. Password the clients have to enter in order to connect.
  17854. @item @code{max-users} (default: @code{100})
  17855. Maximum of users that can be connected to the server at once.
  17856. @item @code{max-user-bandwidth} (default: @code{#f})
  17857. Maximum voice traffic a user can send per second.
  17858. @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
  17859. File name of the sqlite database.
  17860. The service's user will become the owner of the directory.
  17861. @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
  17862. File name of the log file.
  17863. The service's user will become the owner of the directory.
  17864. @item @code{autoban-attempts} (default: @code{10})
  17865. Maximum number of logins a user can make in @code{autoban-timeframe}
  17866. without getting auto banned for @code{autoban-time}.
  17867. @item @code{autoban-timeframe} (default: @code{120})
  17868. Timeframe for autoban in seconds.
  17869. @item @code{autoban-time} (default: @code{300})
  17870. Amount of time in seconds for which a client gets banned
  17871. when violating the autoban limits.
  17872. @item @code{opus-threshold} (default: @code{100})
  17873. Percentage of clients that need to support opus
  17874. before switching over to opus audio codec.
  17875. @item @code{channel-nesting-limit} (default: @code{10})
  17876. How deep channels can be nested at maximum.
  17877. @item @code{channelname-regex} (default: @code{#f})
  17878. A string in form of a Qt regular expression that channel names must conform to.
  17879. @item @code{username-regex} (default: @code{#f})
  17880. A string in form of a Qt regular expression that user names must conform to.
  17881. @item @code{text-message-length} (default: @code{5000})
  17882. Maximum size in bytes that a user can send in one text chat message.
  17883. @item @code{image-message-length} (default: @code{(* 128 1024)})
  17884. Maximum size in bytes that a user can send in one image message.
  17885. @item @code{cert-required?} (default: @code{#f})
  17886. If it is set to @code{#t} clients that use weak password authentication
  17887. will not be accepted. Users must have completed the certificate wizard to join.
  17888. @item @code{remember-channel?} (default: @code{#f})
  17889. Should murmur remember the last channel each user was in when they disconnected
  17890. and put them into the remembered channel when they rejoin.
  17891. @item @code{allow-html?} (default: @code{#f})
  17892. Should html be allowed in text messages, user comments, and channel descriptions.
  17893. @item @code{allow-ping?} (default: @code{#f})
  17894. Setting to true exposes the current user count, the maximum user count, and
  17895. the server's maximum bandwidth per client to unauthenticated users. In the
  17896. Mumble client, this information is shown in the Connect dialog.
  17897. Disabling this setting will prevent public listing of the server.
  17898. @item @code{bonjour?} (default: @code{#f})
  17899. Should the server advertise itself in the local network through the bonjour protocol.
  17900. @item @code{send-version?} (default: @code{#f})
  17901. Should the murmur server version be exposed in ping requests.
  17902. @item @code{log-days} (default: @code{31})
  17903. Murmur also stores logs in the database, which are accessible via RPC.
  17904. The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
  17905. or -1 to disable logging to the database.
  17906. @item @code{obfuscate-ips?} (default: @code{#t})
  17907. Should logged ips be obfuscated to protect the privacy of users.
  17908. @item @code{ssl-cert} (default: @code{#f})
  17909. File name of the SSL/TLS certificate used for encrypted connections.
  17910. @lisp
  17911. (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
  17912. @end lisp
  17913. @item @code{ssl-key} (default: @code{#f})
  17914. Filepath to the ssl private key used for encrypted connections.
  17915. @lisp
  17916. (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
  17917. @end lisp
  17918. @item @code{ssl-dh-params} (default: @code{#f})
  17919. File name of a PEM-encoded file with Diffie-Hellman parameters
  17920. for the SSL/TLS encryption. Alternatively you set it to
  17921. @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
  17922. or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
  17923. @item @code{ssl-ciphers} (default: @code{#f})
  17924. The @code{ssl-ciphers} option chooses the cipher suites to make available for use
  17925. in SSL/TLS.
  17926. This option is specified using
  17927. @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
  17928. OpenSSL cipher list notation}.
  17929. It is recommended that you try your cipher string using 'openssl ciphers <string>'
  17930. before setting it here, to get a feel for which cipher suites you will get.
  17931. After setting this option, it is recommend that you inspect your Murmur log
  17932. to ensure that Murmur is using the cipher suites that you expected it to.
  17933. Note: Changing this option may impact the backwards compatibility of your
  17934. Murmur server, and can remove the ability for older Mumble clients to be able
  17935. to connect to it.
  17936. @item @code{public-registration} (default: @code{#f})
  17937. Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
  17938. You can optionally register your server in the public server list that the
  17939. @code{mumble} client shows on startup.
  17940. You cannot register your server if you have set a @code{server-password},
  17941. or set @code{allow-ping} to @code{#f}.
  17942. It might take a few hours until it shows up in the public list.
  17943. @item @code{file} (default: @code{#f})
  17944. Optional alternative override for this configuration.
  17945. @end table
  17946. @end deftp
  17947. @deftp {Data Type} murmur-public-registration-configuration
  17948. Configuration for public registration of a murmur service.
  17949. @table @asis
  17950. @item @code{name}
  17951. This is a display name for your server. Not to be confused with the hostname.
  17952. @item @code{password}
  17953. A password to identify your registration.
  17954. Subsequent updates will need the same password. Don't lose your password.
  17955. @item @code{url}
  17956. This should be a @code{http://} or @code{https://} link to your web
  17957. site.
  17958. @item @code{hostname} (default: @code{#f})
  17959. By default your server will be listed by its IP address.
  17960. If it is set your server will be linked by this host name instead.
  17961. @end table
  17962. @end deftp
  17963. @node File-Sharing Services
  17964. @subsection File-Sharing Services
  17965. The @code{(gnu services file-sharing)} module provides services that
  17966. assist with transferring files over peer-to-peer file-sharing networks.
  17967. @subsubheading Transmission Daemon Service
  17968. @uref{https://transmissionbt.com/, Transmission} is a flexible
  17969. BitTorrent client that offers a variety of graphical and command-line
  17970. interfaces. A @code{transmission-daemon-service-type} service provides
  17971. Transmission's headless variant, @command{transmission-daemon}, as a
  17972. system service, allowing users to share files via BitTorrent even when
  17973. they are not logged in.
  17974. @deffn {Scheme Variable} transmission-daemon-service-type
  17975. The service type for the Transmission Daemon BitTorrent client. Its
  17976. value must be a @code{transmission-daemon-configuration} object as in
  17977. this example:
  17978. @lisp
  17979. (service transmission-daemon-service-type
  17980. (transmission-daemon-configuration
  17981. ;; Restrict access to the RPC ("control") interface
  17982. (rpc-authentication-required? #t)
  17983. (rpc-username "transmission")
  17984. (rpc-password
  17985. (transmission-password-hash
  17986. "transmission" ; desired password
  17987. "uKd1uMs9")) ; arbitrary salt value
  17988. ;; Accept requests from this and other hosts on the
  17989. ;; local network
  17990. (rpc-whitelist-enabled? #t)
  17991. (rpc-whitelist '("::1" "127.0.0.1" "192.168.0.*"))
  17992. ;; Limit bandwidth use during work hours
  17993. (alt-speed-down (* 1024 2)) ; 2 MB/s
  17994. (alt-speed-up 512) ; 512 kB/s
  17995. (alt-speed-time-enabled? #t)
  17996. (alt-speed-time-day 'weekdays)
  17997. (alt-speed-time-begin
  17998. (+ (* 60 8) 30)) ; 8:30 am
  17999. (alt-speed-time-end
  18000. (+ (* 60 (+ 12 5)) 30)))) ; 5:30 pm
  18001. @end lisp
  18002. @end deffn
  18003. Once the service is started, users can interact with the daemon through
  18004. its Web interface (at @code{http://localhost:9091/}) or by using the
  18005. @command{transmission-remote} command-line tool, available in the
  18006. @code{transmission} package. (Emacs users may want to also consider the
  18007. @code{emacs-transmission} package.) Both communicate with the daemon
  18008. through its remote procedure call (RPC) interface, which by default is
  18009. available to all users on the system; you may wish to change this by
  18010. assigning values to the @code{rpc-authentication-required?},
  18011. @code{rpc-username} and @code{rpc-password} settings, as shown in the
  18012. example above and documented further below.
  18013. The value for @code{rpc-password} must be a password hash of the type
  18014. generated and used by Transmission clients. This can be copied verbatim
  18015. from an existing @file{settings.json} file, if another Transmission
  18016. client is already being used. Otherwise, the
  18017. @code{transmission-password-hash} and @code{transmission-random-salt}
  18018. procedures provided by this module can be used to obtain a suitable hash
  18019. value.
  18020. @deffn {Scheme Procedure} transmission-password-hash @var{password} @var{salt}
  18021. Returns a string containing the result of hashing @var{password}
  18022. together with @var{salt}, in the format recognized by Transmission
  18023. clients for their @code{rpc-password} configuration setting.
  18024. @var{salt} must be an eight-character string. The
  18025. @code{transmission-random-salt} procedure can be used to generate a
  18026. suitable salt value at random.
  18027. @end deffn
  18028. @deffn {Scheme Procedure} transmission-random-salt
  18029. Returns a string containing a random, eight-character salt value of the
  18030. type generated and used by Transmission clients, suitable for passing to
  18031. the @code{transmission-password-hash} procedure.
  18032. @end deffn
  18033. These procedures are accessible from within a Guile REPL started with
  18034. the @command{guix repl} command (@pxref{Invoking guix repl}). This is
  18035. useful for obtaining a random salt value to provide as the second
  18036. parameter to `transmission-password-hash`, as in this example session:
  18037. @example
  18038. $ guix repl
  18039. scheme@@(guix-user)> ,use (gnu services file-sharing)
  18040. scheme@@(guix-user)> (transmission-random-salt)
  18041. $1 = "uKd1uMs9"
  18042. @end example
  18043. Alternatively, a complete password hash can generated in a single step:
  18044. @example
  18045. scheme@@(guix-user)> (transmission-password-hash "transmission"
  18046. (transmission-random-salt))
  18047. $2 = "@{c8bbc6d1740cd8dc819a6e25563b67812c1c19c9VtFPfdsX"
  18048. @end example
  18049. The resulting string can be used as-is for the value of
  18050. @code{rpc-password}, allowing the password to be kept hidden even in the
  18051. operating-system configuration.
  18052. Torrent files downloaded by the daemon are directly accessible only to
  18053. users in the ``transmission'' user group, who receive read-only access
  18054. to the directory specified by the @code{download-dir} configuration
  18055. setting (and also the directory specified by @code{incomplete-dir}, if
  18056. @code{incomplete-dir-enabled?} is @code{#t}). Downloaded files can be
  18057. moved to another directory or deleted altogether using
  18058. @command{transmission-remote} with its @code{--move} and
  18059. @code{--remove-and-delete} options.
  18060. If the @code{watch-dir-enabled?} setting is set to @code{#t}, users in
  18061. the ``transmission'' group are able also to place @file{.torrent} files
  18062. in the directory specified by @code{watch-dir} to have the corresponding
  18063. torrents added by the daemon. (The @code{trash-original-torrent-files?}
  18064. setting controls whether the daemon deletes these files after processing
  18065. them.)
  18066. Some of the daemon's configuration settings can be changed temporarily
  18067. by @command{transmission-remote} and similar tools. To undo these
  18068. changes, use the service's @code{reload} action to have the daemon
  18069. reload its settings from disk:
  18070. @example
  18071. # herd reload transmission-daemon
  18072. @end example
  18073. The full set of available configuration settings is defined by the
  18074. @code{transmission-daemon-configuration} data type.
  18075. @deftp {Data Type} transmission-daemon-configuration
  18076. The data type representing configuration settings for Transmission
  18077. Daemon. These correspond directly to the settings recognized by
  18078. Transmission clients in their @file{settings.json} file.
  18079. @end deftp
  18080. @c The following documentation was initially generated by
  18081. @c (generate-transmission-daemon-documentation) in (gnu services
  18082. @c file-sharing). Manually maintained documentation is better, so we
  18083. @c shouldn't hesitate to edit below as needed. However if the change
  18084. @c you want to make to this documentation can be done in an automated
  18085. @c way, it's probably easier to change (generate-documentation) than to
  18086. @c make it below and have to deal with the churn as Transmission Daemon
  18087. @c updates.
  18088. @c %start of fragment
  18089. Available @code{transmission-daemon-configuration} fields are:
  18090. @deftypevr {@code{transmission-daemon-configuration} parameter} package transmission
  18091. The Transmission package to use.
  18092. @end deftypevr
  18093. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer stop-wait-period
  18094. The period, in seconds, to wait when stopping the service for
  18095. @command{transmission-daemon} to exit before killing its process. This
  18096. allows the daemon time to complete its housekeeping and send a final
  18097. update to trackers as it shuts down. On slow hosts, or hosts with a
  18098. slow network connection, this value may need to be increased.
  18099. Defaults to @samp{10}.
  18100. @end deftypevr
  18101. @deftypevr {@code{transmission-daemon-configuration} parameter} string download-dir
  18102. The directory to which torrent files are downloaded.
  18103. Defaults to @samp{"/var/lib/transmission-daemon/downloads"}.
  18104. @end deftypevr
  18105. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean incomplete-dir-enabled?
  18106. If @code{#t}, files will be held in @code{incomplete-dir} while their
  18107. torrent is being downloaded, then moved to @code{download-dir} once the
  18108. torrent is complete. Otherwise, files for all torrents (including those
  18109. still being downloaded) will be placed in @code{download-dir}.
  18110. Defaults to @samp{#f}.
  18111. @end deftypevr
  18112. @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string incomplete-dir
  18113. The directory in which files from incompletely downloaded torrents will
  18114. be held when @code{incomplete-dir-enabled?} is @code{#t}.
  18115. Defaults to @samp{disabled}.
  18116. @end deftypevr
  18117. @deftypevr {@code{transmission-daemon-configuration} parameter} umask umask
  18118. The file mode creation mask used for downloaded files. (See the
  18119. @command{umask} man page for more information.)
  18120. Defaults to @samp{18}.
  18121. @end deftypevr
  18122. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rename-partial-files?
  18123. When @code{#t}, ``.part'' is appended to the name of partially
  18124. downloaded files.
  18125. Defaults to @samp{#t}.
  18126. @end deftypevr
  18127. @deftypevr {@code{transmission-daemon-configuration} parameter} preallocation-mode preallocation
  18128. The mode by which space should be preallocated for downloaded files, one
  18129. of @code{none}, @code{fast} (or @code{sparse}) and @code{full}.
  18130. Specifying @code{full} will minimize disk fragmentation at a cost to
  18131. file-creation speed.
  18132. Defaults to @samp{fast}.
  18133. @end deftypevr
  18134. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean watch-dir-enabled?
  18135. If @code{#t}, the directory specified by @code{watch-dir} will be
  18136. watched for new @file{.torrent} files and the torrents they describe
  18137. added automatically (and the original files removed, if
  18138. @code{trash-original-torrent-files?} is @code{#t}).
  18139. Defaults to @samp{#f}.
  18140. @end deftypevr
  18141. @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string watch-dir
  18142. The directory to be watched for @file{.torrent} files indicating new
  18143. torrents to be added, when @code{watch-dir-enabled} is @code{#t}.
  18144. Defaults to @samp{disabled}.
  18145. @end deftypevr
  18146. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean trash-original-torrent-files?
  18147. When @code{#t}, @file{.torrent} files will be deleted from the watch
  18148. directory once their torrent has been added (see
  18149. @code{watch-directory-enabled?}).
  18150. Defaults to @samp{#f}.
  18151. @end deftypevr
  18152. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-down-enabled?
  18153. When @code{#t}, the daemon's download speed will be limited to the rate
  18154. specified by @code{speed-limit-down}.
  18155. Defaults to @samp{#f}.
  18156. @end deftypevr
  18157. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-down
  18158. The default global-maximum download speed, in kilobytes per second.
  18159. Defaults to @samp{100}.
  18160. @end deftypevr
  18161. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-up-enabled?
  18162. When @code{#t}, the daemon's upload speed will be limited to the rate
  18163. specified by @code{speed-limit-up}.
  18164. Defaults to @samp{#f}.
  18165. @end deftypevr
  18166. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-up
  18167. The default global-maximum upload speed, in kilobytes per second.
  18168. Defaults to @samp{100}.
  18169. @end deftypevr
  18170. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-enabled?
  18171. When @code{#t}, the alternate speed limits @code{alt-speed-down} and
  18172. @code{alt-speed-up} are used (in place of @code{speed-limit-down} and
  18173. @code{speed-limit-up}, if they are enabled) to constrain the daemon's
  18174. bandwidth usage. This can be scheduled to occur automatically at
  18175. certain times during the week; see @code{alt-speed-time-enabled?}.
  18176. Defaults to @samp{#f}.
  18177. @end deftypevr
  18178. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-down
  18179. The alternate global-maximum download speed, in kilobytes per second.
  18180. Defaults to @samp{50}.
  18181. @end deftypevr
  18182. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-up
  18183. The alternate global-maximum upload speed, in kilobytes per second.
  18184. Defaults to @samp{50}.
  18185. @end deftypevr
  18186. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-time-enabled?
  18187. When @code{#t}, the alternate speed limits @code{alt-speed-down} and
  18188. @code{alt-speed-up} will be enabled automatically during the periods
  18189. specified by @code{alt-speed-time-day}, @code{alt-speed-time-begin} and
  18190. @code{alt-time-speed-end}.
  18191. Defaults to @samp{#f}.
  18192. @end deftypevr
  18193. @deftypevr {@code{transmission-daemon-configuration} parameter} day-list alt-speed-time-day
  18194. The days of the week on which the alternate-speed schedule should be
  18195. used, specified either as a list of days (@code{sunday}, @code{monday},
  18196. and so on) or using one of the symbols @code{weekdays}, @code{weekends}
  18197. or @code{all}.
  18198. Defaults to @samp{all}.
  18199. @end deftypevr
  18200. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-begin
  18201. The time of day at which to enable the alternate speed limits, expressed
  18202. as a number of minutes since midnight.
  18203. Defaults to @samp{540}.
  18204. @end deftypevr
  18205. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-end
  18206. The time of day at which to disable the alternate speed limits,
  18207. expressed as a number of minutes since midnight.
  18208. Defaults to @samp{1020}.
  18209. @end deftypevr
  18210. @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv4
  18211. The IP address at which to listen for peer connections, or ``0.0.0.0''
  18212. to listen at all available IP addresses.
  18213. Defaults to @samp{"0.0.0.0"}.
  18214. @end deftypevr
  18215. @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv6
  18216. The IPv6 address at which to listen for peer connections, or ``::'' to
  18217. listen at all available IPv6 addresses.
  18218. Defaults to @samp{"::"}.
  18219. @end deftypevr
  18220. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean peer-port-random-on-start?
  18221. If @code{#t}, when the daemon starts it will select a port at random on
  18222. which to listen for peer connections, from the range specified
  18223. (inclusively) by @code{peer-port-random-low} and
  18224. @code{peer-port-random-high}. Otherwise, it listens on the port
  18225. specified by @code{peer-port}.
  18226. Defaults to @samp{#f}.
  18227. @end deftypevr
  18228. @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-low
  18229. The lowest selectable port number when @code{peer-port-random-on-start?}
  18230. is @code{#t}.
  18231. Defaults to @samp{49152}.
  18232. @end deftypevr
  18233. @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-high
  18234. The highest selectable port number when @code{peer-port-random-on-start}
  18235. is @code{#t}.
  18236. Defaults to @samp{65535}.
  18237. @end deftypevr
  18238. @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port
  18239. The port on which to listen for peer connections when
  18240. @code{peer-port-random-on-start?} is @code{#f}.
  18241. Defaults to @samp{51413}.
  18242. @end deftypevr
  18243. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean port-forwarding-enabled?
  18244. If @code{#t}, the daemon will attempt to configure port-forwarding on an
  18245. upstream gateway automatically using @acronym{UPnP} and
  18246. @acronym{NAT-PMP}.
  18247. Defaults to @samp{#t}.
  18248. @end deftypevr
  18249. @deftypevr {@code{transmission-daemon-configuration} parameter} encryption-mode encryption
  18250. The encryption preference for peer connections, one of
  18251. @code{prefer-unencrypted-connections},
  18252. @code{prefer-encrypted-connections} or
  18253. @code{require-encrypted-connections}.
  18254. Defaults to @samp{prefer-encrypted-connections}.
  18255. @end deftypevr
  18256. @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string peer-congestion-algorithm
  18257. The TCP congestion-control algorithm to use for peer connections,
  18258. specified using a string recognized by the operating system in calls to
  18259. @code{setsockopt} (or set to @code{disabled}, in which case the
  18260. operating-system default is used).
  18261. Note that on GNU/Linux systems, the kernel must be configured to allow
  18262. processes to use a congestion-control algorithm not in the default set;
  18263. otherwise, it will deny these requests with ``Operation not permitted''.
  18264. To see which algorithms are available on your system and which are
  18265. currently permitted for use, look at the contents of the files
  18266. @file{tcp_available_congestion_control} and
  18267. @file{tcp_allowed_congestion_control} in the @file{/proc/sys/net/ipv4}
  18268. directory.
  18269. As an example, to have Transmission Daemon use
  18270. @uref{http://www-ece.rice.edu/networks/TCP-LP/,the TCP Low Priority
  18271. congestion-control algorithm}, you'll need to modify your kernel
  18272. configuration to build in support for the algorithm, then update your
  18273. operating-system configuration to allow its use by adding a
  18274. @code{sysctl-service-type} service (or updating the existing one's
  18275. configuration) with lines like the following:
  18276. @lisp
  18277. (service sysctl-service-type
  18278. (sysctl-configuration
  18279. (settings
  18280. ("net.ipv4.tcp_allowed_congestion_control" .
  18281. "reno cubic lp"))))
  18282. @end lisp
  18283. The Transmission Daemon configuration can then be updated with
  18284. @lisp
  18285. (peer-congestion-algorithm "lp")
  18286. @end lisp
  18287. and the system reconfigured to have the changes take effect.
  18288. Defaults to @samp{disabled}.
  18289. @end deftypevr
  18290. @deftypevr {@code{transmission-daemon-configuration} parameter} tcp-type-of-service peer-socket-tos
  18291. The type of service to request in outgoing @acronym{TCP} packets, one of
  18292. @code{default}, @code{low-cost}, @code{throughput}, @code{low-delay} and
  18293. @code{reliability}.
  18294. Defaults to @samp{default}.
  18295. @end deftypevr
  18296. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-global
  18297. The global limit on the number of connected peers.
  18298. Defaults to @samp{200}.
  18299. @end deftypevr
  18300. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-per-torrent
  18301. The per-torrent limit on the number of connected peers.
  18302. Defaults to @samp{50}.
  18303. @end deftypevr
  18304. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer upload-slots-per-torrent
  18305. The maximum number of peers to which the daemon will upload data
  18306. simultaneously for each torrent.
  18307. Defaults to @samp{14}.
  18308. @end deftypevr
  18309. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-id-ttl-hours
  18310. The maximum lifespan, in hours, of the peer ID associated with each
  18311. public torrent before it is regenerated.
  18312. Defaults to @samp{6}.
  18313. @end deftypevr
  18314. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean blocklist-enabled?
  18315. When @code{#t}, the daemon will ignore peers mentioned in the blocklist
  18316. it has most recently downloaded from @code{blocklist-url}.
  18317. Defaults to @samp{#f}.
  18318. @end deftypevr
  18319. @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string blocklist-url
  18320. The URL of a peer blocklist (in @acronym{P2P}-plaintext or eMule
  18321. @file{.dat} format) to be periodically downloaded and applied when
  18322. @code{blocklist-enabled?} is @code{#t}.
  18323. Defaults to @samp{disabled}.
  18324. @end deftypevr
  18325. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean download-queue-enabled?
  18326. If @code{#t}, the daemon will be limited to downloading at most
  18327. @code{download-queue-size} non-stalled torrents simultaneously.
  18328. Defaults to @samp{#t}.
  18329. @end deftypevr
  18330. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer download-queue-size
  18331. The size of the daemon's download queue, which limits the number of
  18332. non-stalled torrents it will download at any one time when
  18333. @code{download-queue-enabled?} is @code{#t}.
  18334. Defaults to @samp{5}.
  18335. @end deftypevr
  18336. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean seed-queue-enabled?
  18337. If @code{#t}, the daemon will be limited to seeding at most
  18338. @code{seed-queue-size} non-stalled torrents simultaneously.
  18339. Defaults to @samp{#f}.
  18340. @end deftypevr
  18341. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer seed-queue-size
  18342. The size of the daemon's seed queue, which limits the number of
  18343. non-stalled torrents it will seed at any one time when
  18344. @code{seed-queue-enabled?} is @code{#t}.
  18345. Defaults to @samp{10}.
  18346. @end deftypevr
  18347. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean queue-stalled-enabled?
  18348. When @code{#t}, the daemon will consider torrents for which it has not
  18349. shared data in the past @code{queue-stalled-minutes} minutes to be
  18350. stalled and not count them against its @code{download-queue-size} and
  18351. @code{seed-queue-size} limits.
  18352. Defaults to @samp{#t}.
  18353. @end deftypevr
  18354. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer queue-stalled-minutes
  18355. The maximum period, in minutes, a torrent may be idle before it is
  18356. considered to be stalled, when @code{queue-stalled-enabled?} is
  18357. @code{#t}.
  18358. Defaults to @samp{30}.
  18359. @end deftypevr
  18360. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean ratio-limit-enabled?
  18361. When @code{#t}, a torrent being seeded will automatically be paused once
  18362. it reaches the ratio specified by @code{ratio-limit}.
  18363. Defaults to @samp{#f}.
  18364. @end deftypevr
  18365. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-rational ratio-limit
  18366. The ratio at which a torrent being seeded will be paused, when
  18367. @code{ratio-limit-enabled?} is @code{#t}.
  18368. Defaults to @samp{2.0}.
  18369. @end deftypevr
  18370. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean idle-seeding-limit-enabled?
  18371. When @code{#t}, a torrent being seeded will automatically be paused once
  18372. it has been idle for @code{idle-seeding-limit} minutes.
  18373. Defaults to @samp{#f}.
  18374. @end deftypevr
  18375. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer idle-seeding-limit
  18376. The maximum period, in minutes, a torrent being seeded may be idle
  18377. before it is paused, when @code{idle-seeding-limit-enabled?} is
  18378. @code{#t}.
  18379. Defaults to @samp{30}.
  18380. @end deftypevr
  18381. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean dht-enabled?
  18382. Enable @uref{http://bittorrent.org/beps/bep_0005.html,the distributed
  18383. hash table (@acronym{DHT}) protocol}, which supports the use of
  18384. trackerless torrents.
  18385. Defaults to @samp{#t}.
  18386. @end deftypevr
  18387. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean lpd-enabled?
  18388. Enable @uref{https://en.wikipedia.org/wiki/Local_Peer_Discovery,local
  18389. peer discovery} (@acronym{LPD}), which allows the discovery of peers on
  18390. the local network and may reduce the amount of data sent over the public
  18391. Internet.
  18392. Defaults to @samp{#f}.
  18393. @end deftypevr
  18394. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean pex-enabled?
  18395. Enable @uref{https://en.wikipedia.org/wiki/Peer_exchange,peer exchange}
  18396. (@acronym{PEX}), which reduces the daemon's reliance on external
  18397. trackers and may improve its performance.
  18398. Defaults to @samp{#t}.
  18399. @end deftypevr
  18400. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean utp-enabled?
  18401. Enable @uref{http://bittorrent.org/beps/bep_0029.html,the micro
  18402. transport protocol} (@acronym{uTP}), which aims to reduce the impact of
  18403. BitTorrent traffic on other users of the local network while maintaining
  18404. full utilization of the available bandwidth.
  18405. Defaults to @samp{#t}.
  18406. @end deftypevr
  18407. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-enabled?
  18408. If @code{#t}, enable the remote procedure call (@acronym{RPC})
  18409. interface, which allows remote control of the daemon via its Web
  18410. interface, the @command{transmission-remote} command-line client, and
  18411. similar tools.
  18412. Defaults to @samp{#t}.
  18413. @end deftypevr
  18414. @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-bind-address
  18415. The IP address at which to listen for @acronym{RPC} connections, or
  18416. ``0.0.0.0'' to listen at all available IP addresses.
  18417. Defaults to @samp{"0.0.0.0"}.
  18418. @end deftypevr
  18419. @deftypevr {@code{transmission-daemon-configuration} parameter} port-number rpc-port
  18420. The port on which to listen for @acronym{RPC} connections.
  18421. Defaults to @samp{9091}.
  18422. @end deftypevr
  18423. @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-url
  18424. The path prefix to use in the @acronym{RPC}-endpoint @acronym{URL}.
  18425. Defaults to @samp{"/transmission/"}.
  18426. @end deftypevr
  18427. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-authentication-required?
  18428. When @code{#t}, clients must authenticate (see @code{rpc-username} and
  18429. @code{rpc-password}) when using the @acronym{RPC} interface. Note this
  18430. has the side effect of disabling host-name whitelisting (see
  18431. @code{rpc-host-whitelist-enabled?}.
  18432. Defaults to @samp{#f}.
  18433. @end deftypevr
  18434. @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string rpc-username
  18435. The username required by clients to access the @acronym{RPC} interface
  18436. when @code{rpc-authentication-required?} is @code{#t}.
  18437. Defaults to @samp{disabled}.
  18438. @end deftypevr
  18439. @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-transmission-password-hash rpc-password
  18440. The password required by clients to access the @acronym{RPC} interface
  18441. when @code{rpc-authentication-required?} is @code{#t}. This must be
  18442. specified using a password hash in the format recognized by Transmission
  18443. clients, either copied from an existing @file{settings.json} file or
  18444. generated using the @code{transmission-password-hash} procedure.
  18445. Defaults to @samp{disabled}.
  18446. @end deftypevr
  18447. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-whitelist-enabled?
  18448. When @code{#t}, @acronym{RPC} requests will be accepted only when they
  18449. originate from an address specified in @code{rpc-whitelist}.
  18450. Defaults to @samp{#t}.
  18451. @end deftypevr
  18452. @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-whitelist
  18453. The list of IP and IPv6 addresses from which @acronym{RPC} requests will
  18454. be accepted when @code{rpc-whitelist-enabled?} is @code{#t}. Wildcards
  18455. may be specified using @samp{*}.
  18456. Defaults to @samp{("127.0.0.1" "::1")}.
  18457. @end deftypevr
  18458. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-host-whitelist-enabled?
  18459. When @code{#t}, @acronym{RPC} requests will be accepted only when they
  18460. are addressed to a host named in @code{rpc-host-whitelist}. Note that
  18461. requests to ``localhost'' or ``localhost.'', or to a numeric address,
  18462. are always accepted regardless of these settings.
  18463. Note also this functionality is disabled when
  18464. @code{rpc-authentication-required?} is @code{#t}.
  18465. Defaults to @samp{#t}.
  18466. @end deftypevr
  18467. @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-host-whitelist
  18468. The list of host names recognized by the @acronym{RPC} server when
  18469. @code{rpc-host-whitelist-enabled?} is @code{#t}.
  18470. Defaults to @samp{()}.
  18471. @end deftypevr
  18472. @deftypevr {@code{transmission-daemon-configuration} parameter} message-level message-level
  18473. The minimum severity level of messages to be logged (to
  18474. @file{/var/log/transmission.log}) by the daemon, one of @code{none} (no
  18475. logging), @code{error}, @code{info} and @code{debug}.
  18476. Defaults to @samp{info}.
  18477. @end deftypevr
  18478. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean start-added-torrents?
  18479. When @code{#t}, torrents are started as soon as they are added;
  18480. otherwise, they are added in ``paused'' state.
  18481. Defaults to @samp{#t}.
  18482. @end deftypevr
  18483. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean script-torrent-done-enabled?
  18484. When @code{#t}, the script specified by
  18485. @code{script-torrent-done-filename} will be invoked each time a torrent
  18486. completes.
  18487. Defaults to @samp{#f}.
  18488. @end deftypevr
  18489. @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-file-object script-torrent-done-filename
  18490. A file name or file-like object specifying a script to run each time a
  18491. torrent completes, when @code{script-torrent-done-enabled?} is
  18492. @code{#t}.
  18493. Defaults to @samp{disabled}.
  18494. @end deftypevr
  18495. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean scrape-paused-torrents-enabled?
  18496. When @code{#t}, the daemon will scrape trackers for a torrent even when
  18497. the torrent is paused.
  18498. Defaults to @samp{#t}.
  18499. @end deftypevr
  18500. @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer cache-size-mb
  18501. The amount of memory, in megabytes, to allocate for the daemon's
  18502. in-memory cache. A larger value may increase performance by reducing
  18503. the frequency of disk I/O.
  18504. Defaults to @samp{4}.
  18505. @end deftypevr
  18506. @deftypevr {@code{transmission-daemon-configuration} parameter} boolean prefetch-enabled?
  18507. When @code{#t}, the daemon will try to improve I/O performance by
  18508. hinting to the operating system which data is likely to be read next
  18509. from disk to satisfy requests from peers.
  18510. Defaults to @samp{#t}.
  18511. @end deftypevr
  18512. @c %end of fragment
  18513. @node Monitoring Services
  18514. @subsection Monitoring Services
  18515. @subsubheading Tailon Service
  18516. @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
  18517. viewing and searching log files.
  18518. The following example will configure the service with default values.
  18519. By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
  18520. @lisp
  18521. (service tailon-service-type)
  18522. @end lisp
  18523. The following example customises more of the Tailon configuration,
  18524. adding @command{sed} to the list of allowed commands.
  18525. @lisp
  18526. (service tailon-service-type
  18527. (tailon-configuration
  18528. (config-file
  18529. (tailon-configuration-file
  18530. (allowed-commands '("tail" "grep" "awk" "sed"))))))
  18531. @end lisp
  18532. @deftp {Data Type} tailon-configuration
  18533. Data type representing the configuration of Tailon.
  18534. This type has the following parameters:
  18535. @table @asis
  18536. @item @code{config-file} (default: @code{(tailon-configuration-file)})
  18537. The configuration file to use for Tailon. This can be set to a
  18538. @dfn{tailon-configuration-file} record value, or any gexp
  18539. (@pxref{G-Expressions}).
  18540. For example, to instead use a local file, the @code{local-file} function
  18541. can be used:
  18542. @lisp
  18543. (service tailon-service-type
  18544. (tailon-configuration
  18545. (config-file (local-file "./my-tailon.conf"))))
  18546. @end lisp
  18547. @item @code{package} (default: @code{tailon})
  18548. The tailon package to use.
  18549. @end table
  18550. @end deftp
  18551. @deftp {Data Type} tailon-configuration-file
  18552. Data type representing the configuration options for Tailon.
  18553. This type has the following parameters:
  18554. @table @asis
  18555. @item @code{files} (default: @code{(list "/var/log")})
  18556. List of files to display. The list can include strings for a single file
  18557. or directory, or a list, where the first item is the name of a
  18558. subsection, and the remaining items are the files or directories in that
  18559. subsection.
  18560. @item @code{bind} (default: @code{"localhost:8080"})
  18561. Address and port to which Tailon should bind on.
  18562. @item @code{relative-root} (default: @code{#f})
  18563. URL path to use for Tailon, set to @code{#f} to not use a path.
  18564. @item @code{allow-transfers?} (default: @code{#t})
  18565. Allow downloading the log files in the web interface.
  18566. @item @code{follow-names?} (default: @code{#t})
  18567. Allow tailing of not-yet existent files.
  18568. @item @code{tail-lines} (default: @code{200})
  18569. Number of lines to read initially from each file.
  18570. @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
  18571. Commands to allow running. By default, @code{sed} is disabled.
  18572. @item @code{debug?} (default: @code{#f})
  18573. Set @code{debug?} to @code{#t} to show debug messages.
  18574. @item @code{wrap-lines} (default: @code{#t})
  18575. Initial line wrapping state in the web interface. Set to @code{#t} to
  18576. initially wrap lines (the default), or to @code{#f} to initially not
  18577. wrap lines.
  18578. @item @code{http-auth} (default: @code{#f})
  18579. HTTP authentication type to use. Set to @code{#f} to disable
  18580. authentication (the default). Supported values are @code{"digest"} or
  18581. @code{"basic"}.
  18582. @item @code{users} (default: @code{#f})
  18583. If HTTP authentication is enabled (see @code{http-auth}), access will be
  18584. restricted to the credentials provided here. To configure users, use a
  18585. list of pairs, where the first element of the pair is the username, and
  18586. the 2nd element of the pair is the password.
  18587. @lisp
  18588. (tailon-configuration-file
  18589. (http-auth "basic")
  18590. (users '(("user1" . "password1")
  18591. ("user2" . "password2"))))
  18592. @end lisp
  18593. @end table
  18594. @end deftp
  18595. @subsubheading Darkstat Service
  18596. @cindex darkstat
  18597. Darkstat is a packet sniffer that captures network traffic, calculates
  18598. statistics about usage, and serves reports over HTTP.
  18599. @defvar {Scheme Variable} darkstat-service-type
  18600. This is the service type for the
  18601. @uref{https://unix4lyfe.org/darkstat/, darkstat}
  18602. service, its value must be a @code{darkstat-configuration} record as in
  18603. this example:
  18604. @lisp
  18605. (service darkstat-service-type
  18606. (darkstat-configuration
  18607. (interface "eno1")))
  18608. @end lisp
  18609. @end defvar
  18610. @deftp {Data Type} darkstat-configuration
  18611. Data type representing the configuration of @command{darkstat}.
  18612. @table @asis
  18613. @item @code{package} (default: @code{darkstat})
  18614. The darkstat package to use.
  18615. @item @code{interface}
  18616. Capture traffic on the specified network interface.
  18617. @item @code{port} (default: @code{"667"})
  18618. Bind the web interface to the specified port.
  18619. @item @code{bind-address} (default: @code{"127.0.0.1"})
  18620. Bind the web interface to the specified address.
  18621. @item @code{base} (default: @code{"/"})
  18622. Specify the path of the base URL@. This can be useful if
  18623. @command{darkstat} is accessed via a reverse proxy.
  18624. @end table
  18625. @end deftp
  18626. @subsubheading Prometheus Node Exporter Service
  18627. @cindex prometheus-node-exporter
  18628. The Prometheus ``node exporter'' makes hardware and operating system statistics
  18629. provided by the Linux kernel available for the Prometheus monitoring system.
  18630. This service should be deployed on all physical nodes and virtual machines,
  18631. where monitoring these statistics is desirable.
  18632. @defvar {Scheme variable} prometheus-node-exporter-service-type
  18633. This is the service type for the
  18634. @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
  18635. service, its value must be a @code{prometheus-node-exporter-configuration}.
  18636. @lisp
  18637. (service prometheus-node-exporter-service-type)
  18638. @end lisp
  18639. @end defvar
  18640. @deftp {Data Type} prometheus-node-exporter-configuration
  18641. Data type representing the configuration of @command{node_exporter}.
  18642. @table @asis
  18643. @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
  18644. The prometheus-node-exporter package to use.
  18645. @item @code{web-listen-address} (default: @code{":9100"})
  18646. Bind the web interface to the specified address.
  18647. @item @code{textfile-directory} (default: @code{"/var/lib/prometheus/node-exporter"})
  18648. This directory can be used to export metrics specific to this machine.
  18649. Files containing metrics in the text format, with the filename ending in
  18650. @code{.prom} should be placed in this directory.
  18651. @item @code{extra-options} (default: @code{'()})
  18652. Extra options to pass to the Prometheus node exporter.
  18653. @end table
  18654. @end deftp
  18655. @subsubheading Zabbix server
  18656. @cindex zabbix zabbix-server
  18657. Zabbix provides monitoring metrics, among others network utilization, CPU load
  18658. and disk space consumption:
  18659. @itemize
  18660. @item High performance, high capacity (able to monitor hundreds of thousands of devices).
  18661. @item Auto-discovery of servers and network devices and interfaces.
  18662. @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
  18663. @item Distributed monitoring with centralized web administration.
  18664. @item Native high performance agents.
  18665. @item SLA, and ITIL KPI metrics on reporting.
  18666. @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
  18667. @item Remote command execution through Zabbix proxies.
  18668. @end itemize
  18669. @c %start of fragment
  18670. Available @code{zabbix-server-configuration} fields are:
  18671. @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
  18672. The zabbix-server package.
  18673. @end deftypevr
  18674. @deftypevr {@code{zabbix-server-configuration} parameter} string user
  18675. User who will run the Zabbix server.
  18676. Defaults to @samp{"zabbix"}.
  18677. @end deftypevr
  18678. @deftypevr {@code{zabbix-server-configuration} parameter} group group
  18679. Group who will run the Zabbix server.
  18680. Defaults to @samp{"zabbix"}.
  18681. @end deftypevr
  18682. @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
  18683. Database host name.
  18684. Defaults to @samp{"127.0.0.1"}.
  18685. @end deftypevr
  18686. @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
  18687. Database name.
  18688. Defaults to @samp{"zabbix"}.
  18689. @end deftypevr
  18690. @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
  18691. Database user.
  18692. Defaults to @samp{"zabbix"}.
  18693. @end deftypevr
  18694. @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
  18695. Database password. Please, use @code{include-files} with
  18696. @code{DBPassword=SECRET} inside a specified file instead.
  18697. Defaults to @samp{""}.
  18698. @end deftypevr
  18699. @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
  18700. Database port.
  18701. Defaults to @samp{5432}.
  18702. @end deftypevr
  18703. @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
  18704. Specifies where log messages are written to:
  18705. @itemize @bullet
  18706. @item
  18707. @code{system} - syslog.
  18708. @item
  18709. @code{file} - file specified with @code{log-file} parameter.
  18710. @item
  18711. @code{console} - standard output.
  18712. @end itemize
  18713. Defaults to @samp{""}.
  18714. @end deftypevr
  18715. @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
  18716. Log file name for @code{log-type} @code{file} parameter.
  18717. Defaults to @samp{"/var/log/zabbix/server.log"}.
  18718. @end deftypevr
  18719. @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
  18720. Name of PID file.
  18721. Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
  18722. @end deftypevr
  18723. @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
  18724. The location of certificate authority (CA) files for SSL server
  18725. certificate verification.
  18726. Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
  18727. @end deftypevr
  18728. @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
  18729. Location of SSL client certificates.
  18730. Defaults to @samp{"/etc/ssl/certs"}.
  18731. @end deftypevr
  18732. @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
  18733. Extra options will be appended to Zabbix server configuration file.
  18734. Defaults to @samp{""}.
  18735. @end deftypevr
  18736. @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
  18737. You may include individual files or all files in a directory in the
  18738. configuration file.
  18739. Defaults to @samp{()}.
  18740. @end deftypevr
  18741. @c %end of fragment
  18742. @subsubheading Zabbix agent
  18743. @cindex zabbix zabbix-agent
  18744. Zabbix agent gathers information for Zabbix server.
  18745. @c %start of fragment
  18746. Available @code{zabbix-agent-configuration} fields are:
  18747. @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
  18748. The zabbix-agent package.
  18749. @end deftypevr
  18750. @deftypevr {@code{zabbix-agent-configuration} parameter} string user
  18751. User who will run the Zabbix agent.
  18752. Defaults to @samp{"zabbix"}.
  18753. @end deftypevr
  18754. @deftypevr {@code{zabbix-agent-configuration} parameter} group group
  18755. Group who will run the Zabbix agent.
  18756. Defaults to @samp{"zabbix"}.
  18757. @end deftypevr
  18758. @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
  18759. Unique, case sensitive hostname which is required for active checks and
  18760. must match hostname as configured on the server.
  18761. Defaults to @samp{""}.
  18762. @end deftypevr
  18763. @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
  18764. Specifies where log messages are written to:
  18765. @itemize @bullet
  18766. @item
  18767. @code{system} - syslog.
  18768. @item
  18769. @code{file} - file specified with @code{log-file} parameter.
  18770. @item
  18771. @code{console} - standard output.
  18772. @end itemize
  18773. Defaults to @samp{""}.
  18774. @end deftypevr
  18775. @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
  18776. Log file name for @code{log-type} @code{file} parameter.
  18777. Defaults to @samp{"/var/log/zabbix/agent.log"}.
  18778. @end deftypevr
  18779. @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
  18780. Name of PID file.
  18781. Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
  18782. @end deftypevr
  18783. @deftypevr {@code{zabbix-agent-configuration} parameter} list server
  18784. List of IP addresses, optionally in CIDR notation, or hostnames of
  18785. Zabbix servers and Zabbix proxies. Incoming connections will be
  18786. accepted only from the hosts listed here.
  18787. Defaults to @samp{("127.0.0.1")}.
  18788. @end deftypevr
  18789. @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
  18790. List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
  18791. proxies for active checks. If port is not specified, default port is
  18792. used. If this parameter is not specified, active checks are disabled.
  18793. Defaults to @samp{("127.0.0.1")}.
  18794. @end deftypevr
  18795. @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
  18796. Extra options will be appended to Zabbix server configuration file.
  18797. Defaults to @samp{""}.
  18798. @end deftypevr
  18799. @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
  18800. You may include individual files or all files in a directory in the
  18801. configuration file.
  18802. Defaults to @samp{()}.
  18803. @end deftypevr
  18804. @c %end of fragment
  18805. @subsubheading Zabbix front-end
  18806. @cindex zabbix zabbix-front-end
  18807. This service provides a WEB interface to Zabbix server.
  18808. @c %start of fragment
  18809. Available @code{zabbix-front-end-configuration} fields are:
  18810. @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
  18811. NGINX configuration.
  18812. @end deftypevr
  18813. @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
  18814. Database host name.
  18815. Defaults to @samp{"localhost"}.
  18816. @end deftypevr
  18817. @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
  18818. Database port.
  18819. Defaults to @samp{5432}.
  18820. @end deftypevr
  18821. @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
  18822. Database name.
  18823. Defaults to @samp{"zabbix"}.
  18824. @end deftypevr
  18825. @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
  18826. Database user.
  18827. Defaults to @samp{"zabbix"}.
  18828. @end deftypevr
  18829. @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
  18830. Database password. Please, use @code{db-secret-file} instead.
  18831. Defaults to @samp{""}.
  18832. @end deftypevr
  18833. @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
  18834. Secret file containing the credentials for the Zabbix front-end. The value
  18835. must be a local file name, not a G-expression. You are expected to create
  18836. this file manually. Its contents will be copied into @file{zabbix.conf.php}
  18837. as the value of @code{$DB['PASSWORD']}.
  18838. Defaults to @samp{""}.
  18839. @end deftypevr
  18840. @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
  18841. Zabbix server hostname.
  18842. Defaults to @samp{"localhost"}.
  18843. @end deftypevr
  18844. @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
  18845. Zabbix server port.
  18846. Defaults to @samp{10051}.
  18847. @end deftypevr
  18848. @c %end of fragment
  18849. @node Kerberos Services
  18850. @subsection Kerberos Services
  18851. @cindex Kerberos
  18852. The @code{(gnu services kerberos)} module provides services relating to
  18853. the authentication protocol @dfn{Kerberos}.
  18854. @subsubheading Krb5 Service
  18855. Programs using a Kerberos client library normally
  18856. expect a configuration file in @file{/etc/krb5.conf}.
  18857. This service generates such a file from a definition provided in the
  18858. operating system declaration.
  18859. It does not cause any daemon to be started.
  18860. No ``keytab'' files are provided by this service---you must explicitly create them.
  18861. This service is known to work with the MIT client library, @code{mit-krb5}.
  18862. Other implementations have not been tested.
  18863. @defvr {Scheme Variable} krb5-service-type
  18864. A service type for Kerberos 5 clients.
  18865. @end defvr
  18866. @noindent
  18867. Here is an example of its use:
  18868. @lisp
  18869. (service krb5-service-type
  18870. (krb5-configuration
  18871. (default-realm "EXAMPLE.COM")
  18872. (allow-weak-crypto? #t)
  18873. (realms (list
  18874. (krb5-realm
  18875. (name "EXAMPLE.COM")
  18876. (admin-server "groucho.example.com")
  18877. (kdc "karl.example.com"))
  18878. (krb5-realm
  18879. (name "ARGRX.EDU")
  18880. (admin-server "kerb-admin.argrx.edu")
  18881. (kdc "keys.argrx.edu"))))))
  18882. @end lisp
  18883. @noindent
  18884. This example provides a Kerberos@tie{}5 client configuration which:
  18885. @itemize
  18886. @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
  18887. of which have distinct administration servers and key distribution centers;
  18888. @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
  18889. specified by clients;
  18890. @item Accepts services which only support encryption types known to be weak.
  18891. @end itemize
  18892. The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
  18893. Only the most commonly used ones are described here.
  18894. For a full list, and more detailed explanation of each, see the MIT
  18895. @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
  18896. documentation.
  18897. @deftp {Data Type} krb5-realm
  18898. @cindex realm, kerberos
  18899. @table @asis
  18900. @item @code{name}
  18901. This field is a string identifying the name of the realm.
  18902. A common convention is to use the fully qualified DNS name of your organization,
  18903. converted to upper case.
  18904. @item @code{admin-server}
  18905. This field is a string identifying the host where the administration server is
  18906. running.
  18907. @item @code{kdc}
  18908. This field is a string identifying the key distribution center
  18909. for the realm.
  18910. @end table
  18911. @end deftp
  18912. @deftp {Data Type} krb5-configuration
  18913. @table @asis
  18914. @item @code{allow-weak-crypto?} (default: @code{#f})
  18915. If this flag is @code{#t} then services which only offer encryption algorithms
  18916. known to be weak will be accepted.
  18917. @item @code{default-realm} (default: @code{#f})
  18918. This field should be a string identifying the default Kerberos
  18919. realm for the client.
  18920. You should set this field to the name of your Kerberos realm.
  18921. If this value is @code{#f}
  18922. then a realm must be specified with every Kerberos principal when invoking programs
  18923. such as @command{kinit}.
  18924. @item @code{realms}
  18925. This should be a non-empty list of @code{krb5-realm} objects, which clients may
  18926. access.
  18927. Normally, one of them will have a @code{name} field matching the @code{default-realm}
  18928. field.
  18929. @end table
  18930. @end deftp
  18931. @subsubheading PAM krb5 Service
  18932. @cindex pam-krb5
  18933. The @code{pam-krb5} service allows for login authentication and password
  18934. management via Kerberos.
  18935. You will need this service if you want PAM enabled applications to authenticate
  18936. users using Kerberos.
  18937. @defvr {Scheme Variable} pam-krb5-service-type
  18938. A service type for the Kerberos 5 PAM module.
  18939. @end defvr
  18940. @deftp {Data Type} pam-krb5-configuration
  18941. Data type representing the configuration of the Kerberos 5 PAM module.
  18942. This type has the following parameters:
  18943. @table @asis
  18944. @item @code{pam-krb5} (default: @code{pam-krb5})
  18945. The pam-krb5 package to use.
  18946. @item @code{minimum-uid} (default: @code{1000})
  18947. The smallest user ID for which Kerberos authentications should be attempted.
  18948. Local accounts with lower values will silently fail to authenticate.
  18949. @end table
  18950. @end deftp
  18951. @node LDAP Services
  18952. @subsection LDAP Services
  18953. @cindex LDAP
  18954. @cindex nslcd, LDAP service
  18955. The @code{(gnu services authentication)} module provides the
  18956. @code{nslcd-service-type}, which can be used to authenticate against an LDAP
  18957. server. In addition to configuring the service itself, you may want to add
  18958. @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
  18959. Switch} for detailed information.
  18960. Here is a simple operating system declaration with a default configuration of
  18961. the @code{nslcd-service-type} and a Name Service Switch configuration that
  18962. consults the @code{ldap} name service last:
  18963. @lisp
  18964. (use-service-modules authentication)
  18965. (use-modules (gnu system nss))
  18966. ...
  18967. (operating-system
  18968. ...
  18969. (services
  18970. (cons*
  18971. (service nslcd-service-type)
  18972. (service dhcp-client-service-type)
  18973. %base-services))
  18974. (name-service-switch
  18975. (let ((services (list (name-service (name "db"))
  18976. (name-service (name "files"))
  18977. (name-service (name "ldap")))))
  18978. (name-service-switch
  18979. (inherit %mdns-host-lookup-nss)
  18980. (password services)
  18981. (shadow services)
  18982. (group services)
  18983. (netgroup services)
  18984. (gshadow services)))))
  18985. @end lisp
  18986. @c %start of generated documentation for nslcd-configuration
  18987. Available @code{nslcd-configuration} fields are:
  18988. @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
  18989. The @code{nss-pam-ldapd} package to use.
  18990. @end deftypevr
  18991. @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
  18992. The number of threads to start that can handle requests and perform LDAP
  18993. queries. Each thread opens a separate connection to the LDAP server.
  18994. The default is to start 5 threads.
  18995. Defaults to @samp{disabled}.
  18996. @end deftypevr
  18997. @deftypevr {@code{nslcd-configuration} parameter} string uid
  18998. This specifies the user id with which the daemon should be run.
  18999. Defaults to @samp{"nslcd"}.
  19000. @end deftypevr
  19001. @deftypevr {@code{nslcd-configuration} parameter} string gid
  19002. This specifies the group id with which the daemon should be run.
  19003. Defaults to @samp{"nslcd"}.
  19004. @end deftypevr
  19005. @deftypevr {@code{nslcd-configuration} parameter} log-option log
  19006. This option controls the way logging is done via a list containing
  19007. SCHEME and LEVEL@. The SCHEME argument may either be the symbols
  19008. @samp{none} or @samp{syslog}, or an absolute file name. The LEVEL
  19009. argument is optional and specifies the log level. The log level may be
  19010. one of the following symbols: @samp{crit}, @samp{error}, @samp{warning},
  19011. @samp{notice}, @samp{info} or @samp{debug}. All messages with the
  19012. specified log level or higher are logged.
  19013. Defaults to @samp{("/var/log/nslcd" info)}.
  19014. @end deftypevr
  19015. @deftypevr {@code{nslcd-configuration} parameter} list uri
  19016. The list of LDAP server URIs. Normally, only the first server will be
  19017. used with the following servers as fall-back.
  19018. Defaults to @samp{("ldap://localhost:389/")}.
  19019. @end deftypevr
  19020. @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
  19021. The version of the LDAP protocol to use. The default is to use the
  19022. maximum version supported by the LDAP library.
  19023. Defaults to @samp{disabled}.
  19024. @end deftypevr
  19025. @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
  19026. Specifies the distinguished name with which to bind to the directory
  19027. server for lookups. The default is to bind anonymously.
  19028. Defaults to @samp{disabled}.
  19029. @end deftypevr
  19030. @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
  19031. Specifies the credentials with which to bind. This option is only
  19032. applicable when used with binddn.
  19033. Defaults to @samp{disabled}.
  19034. @end deftypevr
  19035. @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
  19036. Specifies the distinguished name to use when the root user tries to
  19037. modify a user's password using the PAM module.
  19038. Defaults to @samp{disabled}.
  19039. @end deftypevr
  19040. @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
  19041. Specifies the credentials with which to bind if the root user tries to
  19042. change a user's password. This option is only applicable when used with
  19043. rootpwmoddn
  19044. Defaults to @samp{disabled}.
  19045. @end deftypevr
  19046. @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
  19047. Specifies the SASL mechanism to be used when performing SASL
  19048. authentication.
  19049. Defaults to @samp{disabled}.
  19050. @end deftypevr
  19051. @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
  19052. Specifies the SASL realm to be used when performing SASL authentication.
  19053. Defaults to @samp{disabled}.
  19054. @end deftypevr
  19055. @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
  19056. Specifies the authentication identity to be used when performing SASL
  19057. authentication.
  19058. Defaults to @samp{disabled}.
  19059. @end deftypevr
  19060. @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
  19061. Specifies the authorization identity to be used when performing SASL
  19062. authentication.
  19063. Defaults to @samp{disabled}.
  19064. @end deftypevr
  19065. @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
  19066. Determines whether the LDAP server host name should be canonicalised. If
  19067. this is enabled the LDAP library will do a reverse host name lookup. By
  19068. default, it is left up to the LDAP library whether this check is
  19069. performed or not.
  19070. Defaults to @samp{disabled}.
  19071. @end deftypevr
  19072. @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
  19073. Set the name for the GSS-API Kerberos credentials cache.
  19074. Defaults to @samp{disabled}.
  19075. @end deftypevr
  19076. @deftypevr {@code{nslcd-configuration} parameter} string base
  19077. The directory search base.
  19078. Defaults to @samp{"dc=example,dc=com"}.
  19079. @end deftypevr
  19080. @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
  19081. Specifies the search scope (subtree, onelevel, base or children). The
  19082. default scope is subtree; base scope is almost never useful for name
  19083. service lookups; children scope is not supported on all servers.
  19084. Defaults to @samp{(subtree)}.
  19085. @end deftypevr
  19086. @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
  19087. Specifies the policy for dereferencing aliases. The default policy is
  19088. to never dereference aliases.
  19089. Defaults to @samp{disabled}.
  19090. @end deftypevr
  19091. @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
  19092. Specifies whether automatic referral chasing should be enabled. The
  19093. default behaviour is to chase referrals.
  19094. Defaults to @samp{disabled}.
  19095. @end deftypevr
  19096. @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
  19097. This option allows for custom attributes to be looked up instead of the
  19098. default RFC 2307 attributes. It is a list of maps, each consisting of
  19099. the name of a map, the RFC 2307 attribute to match and the query
  19100. expression for the attribute as it is available in the directory.
  19101. Defaults to @samp{()}.
  19102. @end deftypevr
  19103. @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
  19104. A list of filters consisting of the name of a map to which the filter
  19105. applies and an LDAP search filter expression.
  19106. Defaults to @samp{()}.
  19107. @end deftypevr
  19108. @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
  19109. Specifies the time limit in seconds to use when connecting to the
  19110. directory server. The default value is 10 seconds.
  19111. Defaults to @samp{disabled}.
  19112. @end deftypevr
  19113. @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
  19114. Specifies the time limit (in seconds) to wait for a response from the
  19115. LDAP server. A value of zero, which is the default, is to wait
  19116. indefinitely for searches to be completed.
  19117. Defaults to @samp{disabled}.
  19118. @end deftypevr
  19119. @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
  19120. Specifies the period if inactivity (in seconds) after which the con‐
  19121. nection to the LDAP server will be closed. The default is not to time
  19122. out connections.
  19123. Defaults to @samp{disabled}.
  19124. @end deftypevr
  19125. @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
  19126. Specifies the number of seconds to sleep when connecting to all LDAP
  19127. servers fails. By default one second is waited between the first
  19128. failure and the first retry.
  19129. Defaults to @samp{disabled}.
  19130. @end deftypevr
  19131. @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
  19132. Specifies the time after which the LDAP server is considered to be
  19133. permanently unavailable. Once this time is reached retries will be done
  19134. only once per this time period. The default value is 10 seconds.
  19135. Defaults to @samp{disabled}.
  19136. @end deftypevr
  19137. @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
  19138. Specifies whether to use SSL/TLS or not (the default is not to). If
  19139. 'start-tls is specified then StartTLS is used rather than raw LDAP over
  19140. SSL.
  19141. Defaults to @samp{disabled}.
  19142. @end deftypevr
  19143. @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
  19144. Specifies what checks to perform on a server-supplied certificate. The
  19145. meaning of the values is described in the ldap.conf(5) manual page.
  19146. Defaults to @samp{disabled}.
  19147. @end deftypevr
  19148. @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
  19149. Specifies the directory containing X.509 certificates for peer authen‐
  19150. tication. This parameter is ignored when using GnuTLS.
  19151. Defaults to @samp{disabled}.
  19152. @end deftypevr
  19153. @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
  19154. Specifies the path to the X.509 certificate for peer authentication.
  19155. Defaults to @samp{disabled}.
  19156. @end deftypevr
  19157. @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
  19158. Specifies the path to an entropy source. This parameter is ignored when
  19159. using GnuTLS.
  19160. Defaults to @samp{disabled}.
  19161. @end deftypevr
  19162. @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
  19163. Specifies the ciphers to use for TLS as a string.
  19164. Defaults to @samp{disabled}.
  19165. @end deftypevr
  19166. @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
  19167. Specifies the path to the file containing the local certificate for
  19168. client TLS authentication.
  19169. Defaults to @samp{disabled}.
  19170. @end deftypevr
  19171. @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
  19172. Specifies the path to the file containing the private key for client TLS
  19173. authentication.
  19174. Defaults to @samp{disabled}.
  19175. @end deftypevr
  19176. @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
  19177. Set this to a number greater than 0 to request paged results from the
  19178. LDAP server in accordance with RFC2696. The default (0) is to not
  19179. request paged results.
  19180. Defaults to @samp{disabled}.
  19181. @end deftypevr
  19182. @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
  19183. This option prevents group membership lookups through LDAP for the
  19184. specified users. Alternatively, the value 'all-local may be used. With
  19185. that value nslcd builds a full list of non-LDAP users on startup.
  19186. Defaults to @samp{disabled}.
  19187. @end deftypevr
  19188. @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
  19189. This option ensures that LDAP users with a numeric user id lower than
  19190. the specified value are ignored.
  19191. Defaults to @samp{disabled}.
  19192. @end deftypevr
  19193. @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
  19194. This option specifies an offset that is added to all LDAP numeric user
  19195. ids. This can be used to avoid user id collisions with local users.
  19196. Defaults to @samp{disabled}.
  19197. @end deftypevr
  19198. @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
  19199. This option specifies an offset that is added to all LDAP numeric group
  19200. ids. This can be used to avoid user id collisions with local groups.
  19201. Defaults to @samp{disabled}.
  19202. @end deftypevr
  19203. @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
  19204. If this option is set, the member attribute of a group may point to
  19205. another group. Members of nested groups are also returned in the higher
  19206. level group and parent groups are returned when finding groups for a
  19207. specific user. The default is not to perform extra searches for nested
  19208. groups.
  19209. Defaults to @samp{disabled}.
  19210. @end deftypevr
  19211. @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
  19212. If this option is set, the group member list is not retrieved when
  19213. looking up groups. Lookups for finding which groups a user belongs to
  19214. will remain functional so the user will likely still get the correct
  19215. groups assigned on login.
  19216. Defaults to @samp{disabled}.
  19217. @end deftypevr
  19218. @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
  19219. If this option is set, functions which cause all user/group entries to
  19220. be loaded from the directory will not succeed in doing so. This can
  19221. dramatically reduce LDAP server load in situations where there are a
  19222. great number of users and/or groups. This option is not recommended for
  19223. most configurations.
  19224. Defaults to @samp{disabled}.
  19225. @end deftypevr
  19226. @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
  19227. This option can be used to specify how user and group names are verified
  19228. within the system. This pattern is used to check all user and group
  19229. names that are requested and returned from LDAP.
  19230. Defaults to @samp{disabled}.
  19231. @end deftypevr
  19232. @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
  19233. This specifies whether or not to perform searches using case-insensitive
  19234. matching. Enabling this could open up the system to authorization
  19235. bypass vulnerabilities and introduce nscd cache poisoning
  19236. vulnerabilities which allow denial of service.
  19237. Defaults to @samp{disabled}.
  19238. @end deftypevr
  19239. @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
  19240. This option specifies whether password policy controls are requested and
  19241. handled from the LDAP server when performing user authentication.
  19242. Defaults to @samp{disabled}.
  19243. @end deftypevr
  19244. @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
  19245. By default nslcd performs an LDAP search with the user's credentials
  19246. after BIND (authentication) to ensure that the BIND operation was
  19247. successful. The default search is a simple check to see if the user's
  19248. DN exists. A search filter can be specified that will be used instead.
  19249. It should return at least one entry.
  19250. Defaults to @samp{disabled}.
  19251. @end deftypevr
  19252. @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
  19253. This option allows flexible fine tuning of the authorisation check that
  19254. should be performed. The search filter specified is executed and if any
  19255. entries match, access is granted, otherwise access is denied.
  19256. Defaults to @samp{disabled}.
  19257. @end deftypevr
  19258. @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
  19259. If this option is set password modification using pam_ldap will be
  19260. denied and the specified message will be presented to the user instead.
  19261. The message can be used to direct the user to an alternative means of
  19262. changing their password.
  19263. Defaults to @samp{disabled}.
  19264. @end deftypevr
  19265. @deftypevr {@code{nslcd-configuration} parameter} list pam-services
  19266. List of pam service names for which LDAP authentication should suffice.
  19267. Defaults to @samp{()}.
  19268. @end deftypevr
  19269. @c %end of generated documentation for nslcd-configuration
  19270. @node Web Services
  19271. @subsection Web Services
  19272. @cindex web
  19273. @cindex www
  19274. @cindex HTTP
  19275. The @code{(gnu services web)} module provides the Apache HTTP Server,
  19276. the nginx web server, and also a fastcgi wrapper daemon.
  19277. @subsubheading Apache HTTP Server
  19278. @deffn {Scheme Variable} httpd-service-type
  19279. Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
  19280. (@dfn{httpd}). The value for this service type is a
  19281. @code{httpd-configuration} record.
  19282. A simple example configuration is given below.
  19283. @lisp
  19284. (service httpd-service-type
  19285. (httpd-configuration
  19286. (config
  19287. (httpd-config-file
  19288. (server-name "www.example.com")
  19289. (document-root "/srv/http/www.example.com")))))
  19290. @end lisp
  19291. Other services can also extend the @code{httpd-service-type} to add to
  19292. the configuration.
  19293. @lisp
  19294. (simple-service 'www.example.com-server httpd-service-type
  19295. (list
  19296. (httpd-virtualhost
  19297. "*:80"
  19298. (list (string-join '("ServerName www.example.com"
  19299. "DocumentRoot /srv/http/www.example.com")
  19300. "\n")))))
  19301. @end lisp
  19302. @end deffn
  19303. The details for the @code{httpd-configuration}, @code{httpd-module},
  19304. @code{httpd-config-file} and @code{httpd-virtualhost} record types are
  19305. given below.
  19306. @deffn {Data Type} httpd-configuration
  19307. This data type represents the configuration for the httpd service.
  19308. @table @asis
  19309. @item @code{package} (default: @code{httpd})
  19310. The httpd package to use.
  19311. @item @code{pid-file} (default: @code{"/var/run/httpd"})
  19312. The pid file used by the shepherd-service.
  19313. @item @code{config} (default: @code{(httpd-config-file)})
  19314. The configuration file to use with the httpd service. The default value
  19315. is a @code{httpd-config-file} record, but this can also be a different
  19316. G-expression that generates a file, for example a @code{plain-file}. A
  19317. file outside of the store can also be specified through a string.
  19318. @end table
  19319. @end deffn
  19320. @deffn {Data Type} httpd-module
  19321. This data type represents a module for the httpd service.
  19322. @table @asis
  19323. @item @code{name}
  19324. The name of the module.
  19325. @item @code{file}
  19326. The file for the module. This can be relative to the httpd package being
  19327. used, the absolute location of a file, or a G-expression for a file
  19328. within the store, for example @code{(file-append mod-wsgi
  19329. "/modules/mod_wsgi.so")}.
  19330. @end table
  19331. @end deffn
  19332. @defvr {Scheme Variable} %default-httpd-modules
  19333. A default list of @code{httpd-module} objects.
  19334. @end defvr
  19335. @deffn {Data Type} httpd-config-file
  19336. This data type represents a configuration file for the httpd service.
  19337. @table @asis
  19338. @item @code{modules} (default: @code{%default-httpd-modules})
  19339. The modules to load. Additional modules can be added here, or loaded by
  19340. additional configuration.
  19341. For example, in order to handle requests for PHP files, you can use Apache’s
  19342. @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
  19343. @lisp
  19344. (service httpd-service-type
  19345. (httpd-configuration
  19346. (config
  19347. (httpd-config-file
  19348. (modules (cons*
  19349. (httpd-module
  19350. (name "proxy_module")
  19351. (file "modules/mod_proxy.so"))
  19352. (httpd-module
  19353. (name "proxy_fcgi_module")
  19354. (file "modules/mod_proxy_fcgi.so"))
  19355. %default-httpd-modules))
  19356. (extra-config (list "\
  19357. <FilesMatch \\.php$>
  19358. SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
  19359. </FilesMatch>"))))))
  19360. (service php-fpm-service-type
  19361. (php-fpm-configuration
  19362. (socket "/var/run/php-fpm.sock")
  19363. (socket-group "httpd")))
  19364. @end lisp
  19365. @item @code{server-root} (default: @code{httpd})
  19366. The @code{ServerRoot} in the configuration file, defaults to the httpd
  19367. package. Directives including @code{Include} and @code{LoadModule} are
  19368. taken as relative to the server root.
  19369. @item @code{server-name} (default: @code{#f})
  19370. The @code{ServerName} in the configuration file, used to specify the
  19371. request scheme, hostname and port that the server uses to identify
  19372. itself.
  19373. This doesn't need to be set in the server config, and can be specified
  19374. in virtual hosts. The default is @code{#f} to not specify a
  19375. @code{ServerName}.
  19376. @item @code{document-root} (default: @code{"/srv/http"})
  19377. The @code{DocumentRoot} from which files will be served.
  19378. @item @code{listen} (default: @code{'("80")})
  19379. The list of values for the @code{Listen} directives in the config
  19380. file. The value should be a list of strings, when each string can
  19381. specify the port number to listen on, and optionally the IP address and
  19382. protocol to use.
  19383. @item @code{pid-file} (default: @code{"/var/run/httpd"})
  19384. The @code{PidFile} to use. This should match the @code{pid-file} set in
  19385. the @code{httpd-configuration} so that the Shepherd service is
  19386. configured correctly.
  19387. @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
  19388. The @code{ErrorLog} to which the server will log errors.
  19389. @item @code{user} (default: @code{"httpd"})
  19390. The @code{User} which the server will answer requests as.
  19391. @item @code{group} (default: @code{"httpd"})
  19392. The @code{Group} which the server will answer requests as.
  19393. @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
  19394. A flat list of strings and G-expressions which will be added to the end
  19395. of the configuration file.
  19396. Any values which the service is extended with will be appended to this
  19397. list.
  19398. @end table
  19399. @end deffn
  19400. @deffn {Data Type} httpd-virtualhost
  19401. This data type represents a virtualhost configuration block for the httpd service.
  19402. These should be added to the extra-config for the httpd-service.
  19403. @lisp
  19404. (simple-service 'www.example.com-server httpd-service-type
  19405. (list
  19406. (httpd-virtualhost
  19407. "*:80"
  19408. (list (string-join '("ServerName www.example.com"
  19409. "DocumentRoot /srv/http/www.example.com")
  19410. "\n")))))
  19411. @end lisp
  19412. @table @asis
  19413. @item @code{addresses-and-ports}
  19414. The addresses and ports for the @code{VirtualHost} directive.
  19415. @item @code{contents}
  19416. The contents of the @code{VirtualHost} directive, this should be a list
  19417. of strings and G-expressions.
  19418. @end table
  19419. @end deffn
  19420. @subsubheading NGINX
  19421. @deffn {Scheme Variable} nginx-service-type
  19422. Service type for the @uref{https://nginx.org/,NGinx} web server. The
  19423. value for this service type is a @code{<nginx-configuration>} record.
  19424. A simple example configuration is given below.
  19425. @lisp
  19426. (service nginx-service-type
  19427. (nginx-configuration
  19428. (server-blocks
  19429. (list (nginx-server-configuration
  19430. (server-name '("www.example.com"))
  19431. (root "/srv/http/www.example.com"))))))
  19432. @end lisp
  19433. In addition to adding server blocks to the service configuration
  19434. directly, this service can be extended by other services to add server
  19435. blocks, as in this example:
  19436. @lisp
  19437. (simple-service 'my-extra-server nginx-service-type
  19438. (list (nginx-server-configuration
  19439. (root "/srv/http/extra-website")
  19440. (try-files (list "$uri" "$uri/index.html")))))
  19441. @end lisp
  19442. @end deffn
  19443. At startup, @command{nginx} has not yet read its configuration file, so
  19444. it uses a default file to log error messages. If it fails to load its
  19445. configuration file, that is where error messages are logged. After the
  19446. configuration file is loaded, the default error log file changes as per
  19447. configuration. In our case, startup error messages can be found in
  19448. @file{/var/run/nginx/logs/error.log}, and after configuration in
  19449. @file{/var/log/nginx/error.log}. The second location can be changed
  19450. with the @var{log-directory} configuration option.
  19451. @deffn {Data Type} nginx-configuration
  19452. This data type represents the configuration for NGinx. Some
  19453. configuration can be done through this and the other provided record
  19454. types, or alternatively, a config file can be provided.
  19455. @table @asis
  19456. @item @code{nginx} (default: @code{nginx})
  19457. The nginx package to use.
  19458. @item @code{log-directory} (default: @code{"/var/log/nginx"})
  19459. The directory to which NGinx will write log files.
  19460. @item @code{run-directory} (default: @code{"/var/run/nginx"})
  19461. The directory in which NGinx will create a pid file, and write temporary
  19462. files.
  19463. @item @code{server-blocks} (default: @code{'()})
  19464. A list of @dfn{server blocks} to create in the generated configuration
  19465. file, the elements should be of type
  19466. @code{<nginx-server-configuration>}.
  19467. The following example would setup NGinx to serve @code{www.example.com}
  19468. from the @code{/srv/http/www.example.com} directory, without using
  19469. HTTPS.
  19470. @lisp
  19471. (service nginx-service-type
  19472. (nginx-configuration
  19473. (server-blocks
  19474. (list (nginx-server-configuration
  19475. (server-name '("www.example.com"))
  19476. (root "/srv/http/www.example.com"))))))
  19477. @end lisp
  19478. @item @code{upstream-blocks} (default: @code{'()})
  19479. A list of @dfn{upstream blocks} to create in the generated configuration
  19480. file, the elements should be of type
  19481. @code{<nginx-upstream-configuration>}.
  19482. Configuring upstreams through the @code{upstream-blocks} can be useful
  19483. when combined with @code{locations} in the
  19484. @code{<nginx-server-configuration>} records. The following example
  19485. creates a server configuration with one location configuration, that
  19486. will proxy requests to a upstream configuration, which will handle
  19487. requests with two servers.
  19488. @lisp
  19489. (service
  19490. nginx-service-type
  19491. (nginx-configuration
  19492. (server-blocks
  19493. (list (nginx-server-configuration
  19494. (server-name '("www.example.com"))
  19495. (root "/srv/http/www.example.com")
  19496. (locations
  19497. (list
  19498. (nginx-location-configuration
  19499. (uri "/path1")
  19500. (body '("proxy_pass http://server-proxy;"))))))))
  19501. (upstream-blocks
  19502. (list (nginx-upstream-configuration
  19503. (name "server-proxy")
  19504. (servers (list "server1.example.com"
  19505. "server2.example.com")))))))
  19506. @end lisp
  19507. @item @code{file} (default: @code{#f})
  19508. If a configuration @var{file} is provided, this will be used, rather than
  19509. generating a configuration file from the provided @code{log-directory},
  19510. @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
  19511. proper operation, these arguments should match what is in @var{file} to ensure
  19512. that the directories are created when the service is activated.
  19513. This can be useful if you have an existing configuration file, or it's
  19514. not possible to do what is required through the other parts of the
  19515. nginx-configuration record.
  19516. @item @code{server-names-hash-bucket-size} (default: @code{#f})
  19517. Bucket size for the server names hash tables, defaults to @code{#f} to
  19518. use the size of the processors cache line.
  19519. @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
  19520. Maximum bucket size for the server names hash tables.
  19521. @item @code{modules} (default: @code{'()})
  19522. List of nginx dynamic modules to load. This should be a list of file
  19523. names of loadable modules, as in this example:
  19524. @lisp
  19525. (modules
  19526. (list
  19527. (file-append nginx-accept-language-module "\
  19528. /etc/nginx/modules/ngx_http_accept_language_module.so")
  19529. (file-append nginx-lua-module "\
  19530. /etc/nginx/modules/ngx_http_lua_module.so")))
  19531. @end lisp
  19532. @item @code{lua-package-path} (default: @code{'()})
  19533. List of nginx lua packages to load. This should be a list of package
  19534. names of loadable lua modules, as in this example:
  19535. @lisp
  19536. (lua-package-path (list lua-resty-core
  19537. lua-resty-lrucache
  19538. lua-resty-signal
  19539. lua-tablepool
  19540. lua-resty-shell))
  19541. @end lisp
  19542. @item @code{lua-package-cpath} (default: @code{'()})
  19543. List of nginx lua C packages to load. This should be a list of package
  19544. names of loadable lua C modules, as in this example:
  19545. @lisp
  19546. (lua-package-cpath (list lua-resty-signal))
  19547. @end lisp
  19548. @item @code{global-directives} (default: @code{'((events . ()))})
  19549. Association list of global directives for the top level of the nginx
  19550. configuration. Values may themselves be association lists.
  19551. @lisp
  19552. (global-directives
  19553. `((worker_processes . 16)
  19554. (pcre_jit . on)
  19555. (events . ((worker_connections . 1024)))))
  19556. @end lisp
  19557. @item @code{extra-content} (default: @code{""})
  19558. Extra content for the @code{http} block. Should be string or a string
  19559. valued G-expression.
  19560. @end table
  19561. @end deffn
  19562. @deftp {Data Type} nginx-server-configuration
  19563. Data type representing the configuration of an nginx server block.
  19564. This type has the following parameters:
  19565. @table @asis
  19566. @item @code{listen} (default: @code{'("80" "443 ssl")})
  19567. Each @code{listen} directive sets the address and port for IP, or the
  19568. path for a UNIX-domain socket on which the server will accept requests.
  19569. Both address and port, or only address or only port can be specified.
  19570. An address may also be a hostname, for example:
  19571. @lisp
  19572. '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
  19573. @end lisp
  19574. @item @code{server-name} (default: @code{(list 'default)})
  19575. A list of server names this server represents. @code{'default} represents the
  19576. default server for connections matching no other server.
  19577. @item @code{root} (default: @code{"/srv/http"})
  19578. Root of the website nginx will serve.
  19579. @item @code{locations} (default: @code{'()})
  19580. A list of @dfn{nginx-location-configuration} or
  19581. @dfn{nginx-named-location-configuration} records to use within this
  19582. server block.
  19583. @item @code{index} (default: @code{(list "index.html")})
  19584. Index files to look for when clients ask for a directory. If it cannot be found,
  19585. Nginx will send the list of files in the directory.
  19586. @item @code{try-files} (default: @code{'()})
  19587. A list of files whose existence is checked in the specified order.
  19588. @code{nginx} will use the first file it finds to process the request.
  19589. @item @code{ssl-certificate} (default: @code{#f})
  19590. Where to find the certificate for secure connections. Set it to @code{#f} if
  19591. you don't have a certificate or you don't want to use HTTPS.
  19592. @item @code{ssl-certificate-key} (default: @code{#f})
  19593. Where to find the private key for secure connections. Set it to @code{#f} if
  19594. you don't have a key or you don't want to use HTTPS.
  19595. @item @code{server-tokens?} (default: @code{#f})
  19596. Whether the server should add its configuration to response.
  19597. @item @code{raw-content} (default: @code{'()})
  19598. A list of raw lines added to the server block.
  19599. @end table
  19600. @end deftp
  19601. @deftp {Data Type} nginx-upstream-configuration
  19602. Data type representing the configuration of an nginx @code{upstream}
  19603. block. This type has the following parameters:
  19604. @table @asis
  19605. @item @code{name}
  19606. Name for this group of servers.
  19607. @item @code{servers}
  19608. Specify the addresses of the servers in the group. The address can be
  19609. specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
  19610. (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
  19611. prefix @samp{unix:}. For addresses using an IP address or domain name,
  19612. the default port is 80, and a different port can be specified
  19613. explicitly.
  19614. @end table
  19615. @end deftp
  19616. @deftp {Data Type} nginx-location-configuration
  19617. Data type representing the configuration of an nginx @code{location}
  19618. block. This type has the following parameters:
  19619. @table @asis
  19620. @item @code{uri}
  19621. URI which this location block matches.
  19622. @anchor{nginx-location-configuration body}
  19623. @item @code{body}
  19624. Body of the location block, specified as a list of strings. This can contain
  19625. many
  19626. configuration directives. For example, to pass requests to a upstream
  19627. server group defined using an @code{nginx-upstream-configuration} block,
  19628. the following directive would be specified in the body @samp{(list "proxy_pass
  19629. http://upstream-name;")}.
  19630. @end table
  19631. @end deftp
  19632. @deftp {Data Type} nginx-named-location-configuration
  19633. Data type representing the configuration of an nginx named location
  19634. block. Named location blocks are used for request redirection, and not
  19635. used for regular request processing. This type has the following
  19636. parameters:
  19637. @table @asis
  19638. @item @code{name}
  19639. Name to identify this location block.
  19640. @item @code{body}
  19641. @xref{nginx-location-configuration body}, as the body for named location
  19642. blocks can be used in a similar way to the
  19643. @code{nginx-location-configuration body}. One restriction is that the
  19644. body of a named location block cannot contain location blocks.
  19645. @end table
  19646. @end deftp
  19647. @subsubheading Varnish Cache
  19648. @cindex Varnish
  19649. Varnish is a fast cache server that sits in between web applications
  19650. and end users. It proxies requests from clients and caches the
  19651. accessed URLs such that multiple requests for the same resource only
  19652. creates one request to the back-end.
  19653. @defvr {Scheme Variable} varnish-service-type
  19654. Service type for the Varnish daemon.
  19655. @end defvr
  19656. @deftp {Data Type} varnish-configuration
  19657. Data type representing the @code{varnish} service configuration.
  19658. This type has the following parameters:
  19659. @table @asis
  19660. @item @code{package} (default: @code{varnish})
  19661. The Varnish package to use.
  19662. @item @code{name} (default: @code{"default"})
  19663. A name for this Varnish instance. Varnish will create a directory in
  19664. @file{/var/varnish/} with this name and keep temporary files there. If
  19665. the name starts with a forward slash, it is interpreted as an absolute
  19666. directory name.
  19667. Pass the @code{-n} argument to other Varnish programs to connect to the
  19668. named instance, e.g.@: @command{varnishncsa -n default}.
  19669. @item @code{backend} (default: @code{"localhost:8080"})
  19670. The backend to use. This option has no effect if @code{vcl} is set.
  19671. @item @code{vcl} (default: #f)
  19672. The @dfn{VCL} (Varnish Configuration Language) program to run. If this
  19673. is @code{#f}, Varnish will proxy @code{backend} using the default
  19674. configuration. Otherwise this must be a file-like object with valid
  19675. VCL syntax.
  19676. @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
  19677. For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
  19678. can do something along these lines:
  19679. @lisp
  19680. (define %gnu-mirror
  19681. (plain-file "gnu.vcl"
  19682. "vcl 4.1;
  19683. backend gnu @{ .host = \"www.gnu.org\"; @}"))
  19684. (operating-system
  19685. ;; @dots{}
  19686. (services (cons (service varnish-service-type
  19687. (varnish-configuration
  19688. (listen '(":80"))
  19689. (vcl %gnu-mirror)))
  19690. %base-services)))
  19691. @end lisp
  19692. The configuration of an already running Varnish instance can be inspected
  19693. and changed using the @command{varnishadm} program.
  19694. Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
  19695. @url{https://book.varnish-software.com/4.0/,Varnish Book} for
  19696. comprehensive documentation on Varnish and its configuration language.
  19697. @item @code{listen} (default: @code{'("localhost:80")})
  19698. List of addresses Varnish will listen on.
  19699. @item @code{storage} (default: @code{'("malloc,128m")})
  19700. List of storage backends that will be available in VCL.
  19701. @item @code{parameters} (default: @code{'()})
  19702. List of run-time parameters in the form @code{'(("parameter" . "value"))}.
  19703. @item @code{extra-options} (default: @code{'()})
  19704. Additional arguments to pass to the @command{varnishd} process.
  19705. @end table
  19706. @end deftp
  19707. @subsubheading Patchwork
  19708. @cindex Patchwork
  19709. Patchwork is a patch tracking system. It can collect patches sent to a
  19710. mailing list, and display them in a web interface.
  19711. @defvr {Scheme Variable} patchwork-service-type
  19712. Service type for Patchwork.
  19713. @end defvr
  19714. The following example is an example of a minimal service for Patchwork, for
  19715. the @code{patchwork.example.com} domain.
  19716. @lisp
  19717. (service patchwork-service-type
  19718. (patchwork-configuration
  19719. (domain "patchwork.example.com")
  19720. (settings-module
  19721. (patchwork-settings-module
  19722. (allowed-hosts (list domain))
  19723. (default-from-email "patchwork@@patchwork.example.com")))
  19724. (getmail-retriever-config
  19725. (getmail-retriever-configuration
  19726. (type "SimpleIMAPSSLRetriever")
  19727. (server "imap.example.com")
  19728. (port 993)
  19729. (username "patchwork")
  19730. (password-command
  19731. (list (file-append coreutils "/bin/cat")
  19732. "/etc/getmail-patchwork-imap-password"))
  19733. (extra-parameters
  19734. '((mailboxes . ("Patches"))))))))
  19735. @end lisp
  19736. There are three records for configuring the Patchwork service. The
  19737. @code{<patchwork-configuration>} relates to the configuration for Patchwork
  19738. within the HTTPD service.
  19739. The @code{settings-module} field within the @code{<patchwork-configuration>}
  19740. record can be populated with the @code{<patchwork-settings-module>} record,
  19741. which describes a settings module that is generated within the Guix store.
  19742. For the @code{database-configuration} field within the
  19743. @code{<patchwork-settings-module>}, the
  19744. @code{<patchwork-database-configuration>} must be used.
  19745. @deftp {Data Type} patchwork-configuration
  19746. Data type representing the Patchwork service configuration. This type has the
  19747. following parameters:
  19748. @table @asis
  19749. @item @code{patchwork} (default: @code{patchwork})
  19750. The Patchwork package to use.
  19751. @item @code{domain}
  19752. The domain to use for Patchwork, this is used in the HTTPD service virtual
  19753. host.
  19754. @item @code{settings-module}
  19755. The settings module to use for Patchwork. As a Django application, Patchwork
  19756. is configured with a Python module containing the settings. This can either be
  19757. an instance of the @code{<patchwork-settings-module>} record, any other record
  19758. that represents the settings in the store, or a directory outside of the
  19759. store.
  19760. @item @code{static-path} (default: @code{"/static/"})
  19761. The path under which the HTTPD service should serve the static files.
  19762. @item @code{getmail-retriever-config}
  19763. The getmail-retriever-configuration record value to use with
  19764. Patchwork. Getmail will be configured with this value, the messages will be
  19765. delivered to Patchwork.
  19766. @end table
  19767. @end deftp
  19768. @deftp {Data Type} patchwork-settings-module
  19769. Data type representing a settings module for Patchwork. Some of these
  19770. settings relate directly to Patchwork, but others relate to Django, the web
  19771. framework used by Patchwork, or the Django Rest Framework library. This type
  19772. has the following parameters:
  19773. @table @asis
  19774. @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
  19775. The database connection settings used for Patchwork. See the
  19776. @code{<patchwork-database-configuration>} record type for more information.
  19777. @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
  19778. Patchwork, as a Django web application uses a secret key for cryptographically
  19779. signing values. This file should contain a unique unpredictable value.
  19780. If this file does not exist, it will be created and populated with a random
  19781. value by the patchwork-setup shepherd service.
  19782. This setting relates to Django.
  19783. @item @code{allowed-hosts}
  19784. A list of valid hosts for this Patchwork service. This should at least include
  19785. the domain specified in the @code{<patchwork-configuration>} record.
  19786. This is a Django setting.
  19787. @item @code{default-from-email}
  19788. The email address from which Patchwork should send email by default.
  19789. This is a Patchwork setting.
  19790. @item @code{static-url} (default: @code{#f})
  19791. The URL to use when serving static assets. It can be part of a URL, or a full
  19792. URL, but must end in a @code{/}.
  19793. If the default value is used, the @code{static-path} value from the
  19794. @code{<patchwork-configuration>} record will be used.
  19795. This is a Django setting.
  19796. @item @code{admins} (default: @code{'()})
  19797. Email addresses to send the details of errors that occur. Each value should
  19798. be a list containing two elements, the name and then the email address.
  19799. This is a Django setting.
  19800. @item @code{debug?} (default: @code{#f})
  19801. Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
  19802. messages will be shown.
  19803. This is a Django setting.
  19804. @item @code{enable-rest-api?} (default: @code{#t})
  19805. Whether to enable the Patchwork REST API.
  19806. This is a Patchwork setting.
  19807. @item @code{enable-xmlrpc?} (default: @code{#t})
  19808. Whether to enable the XML RPC API.
  19809. This is a Patchwork setting.
  19810. @item @code{force-https-links?} (default: @code{#t})
  19811. Whether to use HTTPS links on Patchwork pages.
  19812. This is a Patchwork setting.
  19813. @item @code{extra-settings} (default: @code{""})
  19814. Extra code to place at the end of the Patchwork settings module.
  19815. @end table
  19816. @end deftp
  19817. @deftp {Data Type} patchwork-database-configuration
  19818. Data type representing the database configuration for Patchwork.
  19819. @table @asis
  19820. @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
  19821. The database engine to use.
  19822. @item @code{name} (default: @code{"patchwork"})
  19823. The name of the database to use.
  19824. @item @code{user} (default: @code{"httpd"})
  19825. The user to connect to the database as.
  19826. @item @code{password} (default: @code{""})
  19827. The password to use when connecting to the database.
  19828. @item @code{host} (default: @code{""})
  19829. The host to make the database connection to.
  19830. @item @code{port} (default: @code{""})
  19831. The port on which to connect to the database.
  19832. @end table
  19833. @end deftp
  19834. @subsubheading Mumi
  19835. @cindex Mumi, Debbugs Web interface
  19836. @cindex Debbugs, Mumi Web interface
  19837. @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
  19838. Web interface to the Debbugs bug tracker, by default for
  19839. @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
  19840. but it also fetches and indexes mail retrieved from Debbugs.
  19841. @defvr {Scheme Variable} mumi-service-type
  19842. This is the service type for Mumi.
  19843. @end defvr
  19844. @deftp {Data Type} mumi-configuration
  19845. Data type representing the Mumi service configuration. This type has the
  19846. following fields:
  19847. @table @asis
  19848. @item @code{mumi} (default: @code{mumi})
  19849. The Mumi package to use.
  19850. @item @code{mailer?} (default: @code{#true})
  19851. Whether to enable or disable the mailer component.
  19852. @item @code{mumi-configuration-sender}
  19853. The email address used as the sender for comments.
  19854. @item @code{mumi-configuration-smtp}
  19855. A URI to configure the SMTP settings for Mailutils. This could be
  19856. something like @code{sendmail:///path/to/bin/msmtp} or any other URI
  19857. supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
  19858. mailutils, GNU@tie{}Mailutils}.
  19859. @end table
  19860. @end deftp
  19861. @subsubheading FastCGI
  19862. @cindex fastcgi
  19863. @cindex fcgiwrap
  19864. FastCGI is an interface between the front-end and the back-end of a web
  19865. service. It is a somewhat legacy facility; new web services should
  19866. generally just talk HTTP between the front-end and the back-end.
  19867. However there are a number of back-end services such as PHP or the
  19868. optimized HTTP Git repository access that use FastCGI, so we have
  19869. support for it in Guix.
  19870. To use FastCGI, you configure the front-end web server (e.g., nginx) to
  19871. dispatch some subset of its requests to the fastcgi backend, which
  19872. listens on a local TCP or UNIX socket. There is an intermediary
  19873. @code{fcgiwrap} program that sits between the actual backend process and
  19874. the web server. The front-end indicates which backend program to run,
  19875. passing that information to the @code{fcgiwrap} process.
  19876. @defvr {Scheme Variable} fcgiwrap-service-type
  19877. A service type for the @code{fcgiwrap} FastCGI proxy.
  19878. @end defvr
  19879. @deftp {Data Type} fcgiwrap-configuration
  19880. Data type representing the configuration of the @code{fcgiwrap} service.
  19881. This type has the following parameters:
  19882. @table @asis
  19883. @item @code{package} (default: @code{fcgiwrap})
  19884. The fcgiwrap package to use.
  19885. @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
  19886. The socket on which the @code{fcgiwrap} process should listen, as a
  19887. string. Valid @var{socket} values include
  19888. @code{unix:@var{/path/to/unix/socket}},
  19889. @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
  19890. @code{tcp6:[@var{ipv6_addr}]:port}.
  19891. @item @code{user} (default: @code{fcgiwrap})
  19892. @itemx @code{group} (default: @code{fcgiwrap})
  19893. The user and group names, as strings, under which to run the
  19894. @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
  19895. the user asks for the specific user or group names @code{fcgiwrap} that
  19896. the corresponding user and/or group is present on the system.
  19897. It is possible to configure a FastCGI-backed web service to pass HTTP
  19898. authentication information from the front-end to the back-end, and to
  19899. allow @code{fcgiwrap} to run the back-end process as a corresponding
  19900. local user. To enable this capability on the back-end, run
  19901. @code{fcgiwrap} as the @code{root} user and group. Note that this
  19902. capability also has to be configured on the front-end as well.
  19903. @end table
  19904. @end deftp
  19905. @cindex php-fpm
  19906. PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
  19907. with some additional features useful for sites of any size.
  19908. These features include:
  19909. @itemize @bullet
  19910. @item Adaptive process spawning
  19911. @item Basic statistics (similar to Apache's mod_status)
  19912. @item Advanced process management with graceful stop/start
  19913. @item Ability to start workers with different uid/gid/chroot/environment
  19914. and different php.ini (replaces safe_mode)
  19915. @item Stdout & stderr logging
  19916. @item Emergency restart in case of accidental opcode cache destruction
  19917. @item Accelerated upload support
  19918. @item Support for a "slowlog"
  19919. @item Enhancements to FastCGI, such as fastcgi_finish_request() -
  19920. a special function to finish request & flush all data while continuing to do
  19921. something time-consuming (video converting, stats processing, etc.)
  19922. @end itemize
  19923. ...@: and much more.
  19924. @defvr {Scheme Variable} php-fpm-service-type
  19925. A Service type for @code{php-fpm}.
  19926. @end defvr
  19927. @deftp {Data Type} php-fpm-configuration
  19928. Data Type for php-fpm service configuration.
  19929. @table @asis
  19930. @item @code{php} (default: @code{php})
  19931. The php package to use.
  19932. @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
  19933. The address on which to accept FastCGI requests. Valid syntaxes are:
  19934. @table @asis
  19935. @item @code{"ip.add.re.ss:port"}
  19936. Listen on a TCP socket to a specific address on a specific port.
  19937. @item @code{"port"}
  19938. Listen on a TCP socket to all addresses on a specific port.
  19939. @item @code{"/path/to/unix/socket"}
  19940. Listen on a unix socket.
  19941. @end table
  19942. @item @code{user} (default: @code{php-fpm})
  19943. User who will own the php worker processes.
  19944. @item @code{group} (default: @code{php-fpm})
  19945. Group of the worker processes.
  19946. @item @code{socket-user} (default: @code{php-fpm})
  19947. User who can speak to the php-fpm socket.
  19948. @item @code{socket-group} (default: @code{nginx})
  19949. Group that can speak to the php-fpm socket.
  19950. @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
  19951. The process id of the php-fpm process is written to this file
  19952. once the service has started.
  19953. @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
  19954. Log for the php-fpm master process.
  19955. @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
  19956. Detailed settings for the php-fpm process manager.
  19957. Must be one of:
  19958. @table @asis
  19959. @item @code{<php-fpm-dynamic-process-manager-configuration>}
  19960. @item @code{<php-fpm-static-process-manager-configuration>}
  19961. @item @code{<php-fpm-on-demand-process-manager-configuration>}
  19962. @end table
  19963. @item @code{display-errors} (default @code{#f})
  19964. Determines whether php errors and warning should be sent to clients
  19965. and displayed in their browsers.
  19966. This is useful for local php development, but a security risk for public sites,
  19967. as error messages can reveal passwords and personal data.
  19968. @item @code{timezone} (default @code{#f})
  19969. Specifies @code{php_admin_value[date.timezone]} parameter.
  19970. @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
  19971. This file will log the @code{stderr} outputs of php worker processes.
  19972. Can be set to @code{#f} to disable logging.
  19973. @item @code{file} (default @code{#f})
  19974. An optional override of the whole configuration.
  19975. You can use the @code{mixed-text-file} function or an absolute filepath for it.
  19976. @item @code{php-ini-file} (default @code{#f})
  19977. An optional override of the default php settings.
  19978. It may be any ``file-like'' object (@pxref{G-Expressions, file-like objects}).
  19979. You can use the @code{mixed-text-file} function or an absolute filepath for it.
  19980. For local development it is useful to set a higher timeout and memory
  19981. limit for spawned php processes. This be accomplished with the
  19982. following operating system configuration snippet:
  19983. @lisp
  19984. (define %local-php-ini
  19985. (plain-file "php.ini"
  19986. "memory_limit = 2G
  19987. max_execution_time = 1800"))
  19988. (operating-system
  19989. ;; @dots{}
  19990. (services (cons (service php-fpm-service-type
  19991. (php-fpm-configuration
  19992. (php-ini-file %local-php-ini)))
  19993. %base-services)))
  19994. @end lisp
  19995. Consult the @url{https://www.php.net/manual/en/ini.core.php,core php.ini
  19996. directives} for comprehensive documentation on the acceptable
  19997. @file{php.ini} directives.
  19998. @end table
  19999. @end deftp
  20000. @deftp {Data type} php-fpm-dynamic-process-manager-configuration
  20001. Data Type for the @code{dynamic} php-fpm process manager. With the
  20002. @code{dynamic} process manager, spare worker processes are kept around
  20003. based on it's configured limits.
  20004. @table @asis
  20005. @item @code{max-children} (default: @code{5})
  20006. Maximum of worker processes.
  20007. @item @code{start-servers} (default: @code{2})
  20008. How many worker processes should be started on start-up.
  20009. @item @code{min-spare-servers} (default: @code{1})
  20010. How many spare worker processes should be kept around at minimum.
  20011. @item @code{max-spare-servers} (default: @code{3})
  20012. How many spare worker processes should be kept around at maximum.
  20013. @end table
  20014. @end deftp
  20015. @deftp {Data type} php-fpm-static-process-manager-configuration
  20016. Data Type for the @code{static} php-fpm process manager. With the
  20017. @code{static} process manager, an unchanging number of worker processes
  20018. are created.
  20019. @table @asis
  20020. @item @code{max-children} (default: @code{5})
  20021. Maximum of worker processes.
  20022. @end table
  20023. @end deftp
  20024. @deftp {Data type} php-fpm-on-demand-process-manager-configuration
  20025. Data Type for the @code{on-demand} php-fpm process manager. With the
  20026. @code{on-demand} process manager, worker processes are only created as
  20027. requests arrive.
  20028. @table @asis
  20029. @item @code{max-children} (default: @code{5})
  20030. Maximum of worker processes.
  20031. @item @code{process-idle-timeout} (default: @code{10})
  20032. The time in seconds after which a process with no requests is killed.
  20033. @end table
  20034. @end deftp
  20035. @deffn {Scheme Procedure} nginx-php-location @
  20036. [#:nginx-package nginx] @
  20037. [socket (string-append "/var/run/php" @
  20038. (version-major (package-version php)) @
  20039. "-fpm.sock")]
  20040. A helper function to quickly add php to an @code{nginx-server-configuration}.
  20041. @end deffn
  20042. A simple services setup for nginx with php can look like this:
  20043. @lisp
  20044. (services (cons* (service dhcp-client-service-type)
  20045. (service php-fpm-service-type)
  20046. (service nginx-service-type
  20047. (nginx-server-configuration
  20048. (server-name '("example.com"))
  20049. (root "/srv/http/")
  20050. (locations
  20051. (list (nginx-php-location)))
  20052. (listen '("80"))
  20053. (ssl-certificate #f)
  20054. (ssl-certificate-key #f)))
  20055. %base-services))
  20056. @end lisp
  20057. @cindex cat-avatar-generator
  20058. The cat avatar generator is a simple service to demonstrate the use of php-fpm
  20059. in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
  20060. the hash of a user's email address.
  20061. @deffn {Scheme Procedure} cat-avatar-generator-service @
  20062. [#:cache-dir "/var/cache/cat-avatar-generator"] @
  20063. [#:package cat-avatar-generator] @
  20064. [#:configuration (nginx-server-configuration)]
  20065. Returns an nginx-server-configuration that inherits @code{configuration}. It
  20066. extends the nginx configuration to add a server block that serves @code{package},
  20067. a version of cat-avatar-generator. During execution, cat-avatar-generator will
  20068. be able to use @code{cache-dir} as its cache directory.
  20069. @end deffn
  20070. A simple setup for cat-avatar-generator can look like this:
  20071. @lisp
  20072. (services (cons* (cat-avatar-generator-service
  20073. #:configuration
  20074. (nginx-server-configuration
  20075. (server-name '("example.com"))))
  20076. ...
  20077. %base-services))
  20078. @end lisp
  20079. @subsubheading Hpcguix-web
  20080. @cindex hpcguix-web
  20081. The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
  20082. program is a customizable web interface to browse Guix packages,
  20083. initially designed for users of high-performance computing (HPC)
  20084. clusters.
  20085. @defvr {Scheme Variable} hpcguix-web-service-type
  20086. The service type for @code{hpcguix-web}.
  20087. @end defvr
  20088. @deftp {Data Type} hpcguix-web-configuration
  20089. Data type for the hpcguix-web service configuration.
  20090. @table @asis
  20091. @item @code{specs}
  20092. A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
  20093. configuration. The main items available in this spec are:
  20094. @table @asis
  20095. @item @code{title-prefix} (default: @code{"hpcguix | "})
  20096. The page title prefix.
  20097. @item @code{guix-command} (default: @code{"guix"})
  20098. The @command{guix} command.
  20099. @item @code{package-filter-proc} (default: @code{(const #t)})
  20100. A procedure specifying how to filter packages that are displayed.
  20101. @item @code{package-page-extension-proc} (default: @code{(const '())})
  20102. Extension package for @code{hpcguix-web}.
  20103. @item @code{menu} (default: @code{'()})
  20104. Additional entry in page @code{menu}.
  20105. @item @code{channels} (default: @code{%default-channels})
  20106. List of channels from which the package list is built (@pxref{Channels}).
  20107. @item @code{package-list-expiration} (default: @code{(* 12 3600)})
  20108. The expiration time, in seconds, after which the package list is rebuilt from
  20109. the latest instances of the given channels.
  20110. @end table
  20111. See the hpcguix-web repository for a
  20112. @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
  20113. complete example}.
  20114. @item @code{package} (default: @code{hpcguix-web})
  20115. The hpcguix-web package to use.
  20116. @end table
  20117. @end deftp
  20118. A typical hpcguix-web service declaration looks like this:
  20119. @lisp
  20120. (service hpcguix-web-service-type
  20121. (hpcguix-web-configuration
  20122. (specs
  20123. #~(define site-config
  20124. (hpcweb-configuration
  20125. (title-prefix "Guix-HPC - ")
  20126. (menu '(("/about" "ABOUT"))))))))
  20127. @end lisp
  20128. @quotation Note
  20129. The hpcguix-web service periodically updates the package list it publishes by
  20130. pulling channels from Git. To that end, it needs to access X.509 certificates
  20131. so that it can authenticate Git servers when communicating over HTTPS, and it
  20132. assumes that @file{/etc/ssl/certs} contains those certificates.
  20133. Thus, make sure to add @code{nss-certs} or another certificate package to the
  20134. @code{packages} field of your configuration. @ref{X.509 Certificates}, for
  20135. more information on X.509 certificates.
  20136. @end quotation
  20137. @subsubheading gmnisrv
  20138. @cindex gmnisrv
  20139. The @uref{https://git.sr.ht/~sircmpwn/gmnisrv, gmnisrv} program is a
  20140. simple @uref{https://gemini.circumlunar.space/, Gemini} protocol server.
  20141. @deffn {Scheme Variable} gmnisrv-service-type
  20142. This is the type of the gmnisrv service, whose value should be a
  20143. @code{gmnisrv-configuration} object, as in this example:
  20144. @lisp
  20145. (service gmnisrv-service-type
  20146. (gmnisrv-configuration
  20147. (config-file (local-file "./my-gmnisrv.ini"))))
  20148. @end lisp
  20149. @end deffn
  20150. @deftp {Data Type} gmnisrv-configuration
  20151. Data type representing the configuration of gmnisrv.
  20152. @table @asis
  20153. @item @code{package} (default: @var{gmnisrv})
  20154. Package object of the gmnisrv server.
  20155. @item @code{config-file} (default: @code{%default-gmnisrv-config-file})
  20156. File-like object of the gmnisrv configuration file to use. The default
  20157. configuration listens on port 1965 and serves files from
  20158. @file{/srv/gemini}. Certificates are stored in
  20159. @file{/var/lib/gemini/certs}. For more information, run @command{man
  20160. gmnisrv} and @command{man gmnisrv.ini}.
  20161. @end table
  20162. @end deftp
  20163. @subsubheading Agate
  20164. @cindex agate
  20165. The @uref{gemini://qwertqwefsday.eu/agate.gmi, Agate}
  20166. (@uref{https://github.com/mbrubeck/agate, GitHub page over HTTPS})
  20167. program is a simple @uref{https://gemini.circumlunar.space/, Gemini}
  20168. protocol server written in Rust.
  20169. @deffn {Scheme Variable} agate-service-type
  20170. This is the type of the agate service, whose value should be an
  20171. @code{agate-service-type} object, as in this example:
  20172. @lisp
  20173. (service agate-service-type
  20174. (agate-configuration
  20175. (content "/srv/gemini")
  20176. (cert "/srv/cert.pem")
  20177. (key "/srv/key.rsa")))
  20178. @end lisp
  20179. The example above represents the minimal tweaking necessary to get Agate
  20180. up and running. Specifying the path to the certificate and key is
  20181. always necessary, as the Gemini protocol requires TLS by default.
  20182. To obtain a certificate and a key, you could, for example, use OpenSSL,
  20183. running a command similar to the following example:
  20184. @example
  20185. openssl req -x509 -newkey rsa:4096 -keyout key.rsa -out cert.pem \
  20186. -days 3650 -nodes -subj "/CN=example.com"
  20187. @end example
  20188. Of course, you'll have to replace @i{example.com} with your own domain
  20189. name, and then point the Agate configuration towards the path of the
  20190. generated key and certificate.
  20191. @end deffn
  20192. @deftp {Data Type} agate-configuration
  20193. Data type representing the configuration of Agate.
  20194. @table @asis
  20195. @item @code{package} (default: @code{agate})
  20196. The package object of the Agate server.
  20197. @item @code{content} (default: @file{"/srv/gemini"})
  20198. The directory from which Agate will serve files.
  20199. @item @code{cert} (default: @code{#f})
  20200. The path to the TLS certificate PEM file to be used for encrypted
  20201. connections. Must be filled in with a value from the user.
  20202. @item @code{key} (default: @code{#f})
  20203. The path to the PKCS8 private key file to be used for encrypted
  20204. connections. Must be filled in with a value from the user.
  20205. @item @code{addr} (default: @code{'("0.0.0.0:1965" "[::]:1965")})
  20206. A list of the addresses to listen on.
  20207. @item @code{hostname} (default: @code{#f})
  20208. The domain name of this Gemini server. Optional.
  20209. @item @code{lang} (default: @code{#f})
  20210. RFC 4646 language code(s) for text/gemini documents. Optional.
  20211. @item @code{silent?} (default: @code{#f})
  20212. Set to @code{#t} to disable logging output.
  20213. @item @code{serve-secret?} (default: @code{#f})
  20214. Set to @code{#t} to serve secret files (files/directories starting with
  20215. a dot).
  20216. @item @code{log-ip?} (default: @code{#t})
  20217. Whether or not to output IP addresses when logging.
  20218. @item @code{user} (default: @code{"agate"})
  20219. Owner of the @code{agate} process.
  20220. @item @code{group} (default: @code{"agate"})
  20221. Owner's group of the @code{agate} process.
  20222. @item @code{log-file} (default: @file{"/var/log/agate.log"})
  20223. The file which should store the logging output of Agate.
  20224. @end table
  20225. @end deftp
  20226. @node Certificate Services
  20227. @subsection Certificate Services
  20228. @cindex Web
  20229. @cindex HTTP, HTTPS
  20230. @cindex Let's Encrypt
  20231. @cindex TLS certificates
  20232. The @code{(gnu services certbot)} module provides a service to
  20233. automatically obtain a valid TLS certificate from the Let's Encrypt
  20234. certificate authority. These certificates can then be used to serve
  20235. content securely over HTTPS or other TLS-based protocols, with the
  20236. knowledge that the client will be able to verify the server's
  20237. authenticity.
  20238. @url{https://letsencrypt.org/, Let's Encrypt} provides the
  20239. @code{certbot} tool to automate the certification process. This tool
  20240. first securely generates a key on the server. It then makes a request
  20241. to the Let's Encrypt certificate authority (CA) to sign the key. The CA
  20242. checks that the request originates from the host in question by using a
  20243. challenge-response protocol, requiring the server to provide its
  20244. response over HTTP@. If that protocol completes successfully, the CA
  20245. signs the key, resulting in a certificate. That certificate is valid
  20246. for a limited period of time, and therefore to continue to provide TLS
  20247. services, the server needs to periodically ask the CA to renew its
  20248. signature.
  20249. The certbot service automates this process: the initial key
  20250. generation, the initial certification request to the Let's Encrypt
  20251. service, the web server challenge/response integration, writing the
  20252. certificate to disk, the automated periodic renewals, and the deployment
  20253. tasks associated with the renewal (e.g.@: reloading services, copying keys
  20254. with different permissions).
  20255. Certbot is run twice a day, at a random minute within the hour. It
  20256. won't do anything until your certificates are due for renewal or
  20257. revoked, but running it regularly would give your service a chance of
  20258. staying online in case a Let's Encrypt-initiated revocation happened for
  20259. some reason.
  20260. By using this service, you agree to the ACME Subscriber Agreement, which
  20261. can be found there:
  20262. @url{https://acme-v01.api.letsencrypt.org/directory}.
  20263. @defvr {Scheme Variable} certbot-service-type
  20264. A service type for the @code{certbot} Let's Encrypt client. Its value
  20265. must be a @code{certbot-configuration} record as in this example:
  20266. @lisp
  20267. (define %nginx-deploy-hook
  20268. (program-file
  20269. "nginx-deploy-hook"
  20270. #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
  20271. (kill pid SIGHUP))))
  20272. (service certbot-service-type
  20273. (certbot-configuration
  20274. (email "foo@@example.net")
  20275. (certificates
  20276. (list
  20277. (certificate-configuration
  20278. (domains '("example.net" "www.example.net"))
  20279. (deploy-hook %nginx-deploy-hook))
  20280. (certificate-configuration
  20281. (domains '("bar.example.net")))))))
  20282. @end lisp
  20283. See below for details about @code{certbot-configuration}.
  20284. @end defvr
  20285. @deftp {Data Type} certbot-configuration
  20286. Data type representing the configuration of the @code{certbot} service.
  20287. This type has the following parameters:
  20288. @table @asis
  20289. @item @code{package} (default: @code{certbot})
  20290. The certbot package to use.
  20291. @item @code{webroot} (default: @code{/var/www})
  20292. The directory from which to serve the Let's Encrypt challenge/response
  20293. files.
  20294. @item @code{certificates} (default: @code{()})
  20295. A list of @code{certificates-configuration}s for which to generate
  20296. certificates and request signatures. Each certificate has a @code{name}
  20297. and several @code{domains}.
  20298. @item @code{email} (default: @code{#f})
  20299. Optional email address used for registration and recovery contact.
  20300. Setting this is encouraged as it allows you to receive important
  20301. notifications about the account and issued certificates.
  20302. @item @code{server} (default: @code{#f})
  20303. Optional URL of ACME server. Setting this overrides certbot's default,
  20304. which is the Let's Encrypt server.
  20305. @item @code{rsa-key-size} (default: @code{2048})
  20306. Size of the RSA key.
  20307. @item @code{default-location} (default: @i{see below})
  20308. The default @code{nginx-location-configuration}. Because @code{certbot}
  20309. needs to be able to serve challenges and responses, it needs to be able
  20310. to run a web server. It does so by extending the @code{nginx} web
  20311. service with an @code{nginx-server-configuration} listening on the
  20312. @var{domains} on port 80, and which has a
  20313. @code{nginx-location-configuration} for the @code{/.well-known/} URI
  20314. path subspace used by Let's Encrypt. @xref{Web Services}, for more on
  20315. these nginx configuration data types.
  20316. Requests to other URL paths will be matched by the
  20317. @code{default-location}, which if present is added to all
  20318. @code{nginx-server-configuration}s.
  20319. By default, the @code{default-location} will issue a redirect from
  20320. @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
  20321. you to define what to serve on your site via @code{https}.
  20322. Pass @code{#f} to not issue a default location.
  20323. @end table
  20324. @end deftp
  20325. @deftp {Data Type} certificate-configuration
  20326. Data type representing the configuration of a certificate.
  20327. This type has the following parameters:
  20328. @table @asis
  20329. @item @code{name} (default: @i{see below})
  20330. This name is used by Certbot for housekeeping and in file paths; it
  20331. doesn't affect the content of the certificate itself. To see
  20332. certificate names, run @code{certbot certificates}.
  20333. Its default is the first provided domain.
  20334. @item @code{domains} (default: @code{()})
  20335. The first domain provided will be the subject CN of the certificate, and
  20336. all domains will be Subject Alternative Names on the certificate.
  20337. @item @code{challenge} (default: @code{#f})
  20338. The challenge type that has to be run by certbot. If @code{#f} is specified,
  20339. default to the HTTP challenge. If a value is specified, defaults to the
  20340. manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
  20341. the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
  20342. and gives Let's Encrypt permission to log the public IP address of the
  20343. requesting machine.
  20344. @item @code{authentication-hook} (default: @code{#f})
  20345. Command to be run in a shell once for each certificate challenge to be
  20346. answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
  20347. will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
  20348. contains the validation string and @code{$CERTBOT_TOKEN} contains the
  20349. file name of the resource requested when performing an HTTP-01 challenge.
  20350. @item @code{cleanup-hook} (default: @code{#f})
  20351. Command to be run in a shell once for each certificate challenge that
  20352. have been answered by the @code{auth-hook}. For this command, the shell
  20353. variables available in the @code{auth-hook} script are still available, and
  20354. additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
  20355. of the @code{auth-hook} script.
  20356. @item @code{deploy-hook} (default: @code{#f})
  20357. Command to be run in a shell once for each successfully issued
  20358. certificate. For this command, the shell variable
  20359. @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
  20360. example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
  20361. certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
  20362. contain a space-delimited list of renewed certificate domains (for
  20363. example, @samp{"example.com www.example.com"}.
  20364. @end table
  20365. @end deftp
  20366. For each @code{certificate-configuration}, the certificate is saved to
  20367. @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
  20368. saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
  20369. @node DNS Services
  20370. @subsection DNS Services
  20371. @cindex DNS (domain name system)
  20372. @cindex domain name system (DNS)
  20373. The @code{(gnu services dns)} module provides services related to the
  20374. @dfn{domain name system} (DNS). It provides a server service for hosting
  20375. an @emph{authoritative} DNS server for multiple zones, slave or master.
  20376. This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
  20377. caching and forwarding DNS server for the LAN, which uses
  20378. @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
  20379. @subsubheading Knot Service
  20380. An example configuration of an authoritative server for two zones, one master
  20381. and one slave, is:
  20382. @lisp
  20383. (define-zone-entries example.org.zone
  20384. ;; Name TTL Class Type Data
  20385. ("@@" "" "IN" "A" "127.0.0.1")
  20386. ("@@" "" "IN" "NS" "ns")
  20387. ("ns" "" "IN" "A" "127.0.0.1"))
  20388. (define master-zone
  20389. (knot-zone-configuration
  20390. (domain "example.org")
  20391. (zone (zone-file
  20392. (origin "example.org")
  20393. (entries example.org.zone)))))
  20394. (define slave-zone
  20395. (knot-zone-configuration
  20396. (domain "plop.org")
  20397. (dnssec-policy "default")
  20398. (master (list "plop-master"))))
  20399. (define plop-master
  20400. (knot-remote-configuration
  20401. (id "plop-master")
  20402. (address (list "208.76.58.171"))))
  20403. (operating-system
  20404. ;; ...
  20405. (services (cons* (service knot-service-type
  20406. (knot-configuration
  20407. (remotes (list plop-master))
  20408. (zones (list master-zone slave-zone))))
  20409. ;; ...
  20410. %base-services)))
  20411. @end lisp
  20412. @deffn {Scheme Variable} knot-service-type
  20413. This is the type for the Knot DNS server.
  20414. Knot DNS is an authoritative DNS server, meaning that it can serve multiple
  20415. zones, that is to say domain names you would buy from a registrar. This server
  20416. is not a resolver, meaning that it can only resolve names for which it is
  20417. authoritative. This server can be configured to serve zones as a master server
  20418. or a slave server as a per-zone basis. Slave zones will get their data from
  20419. masters, and will serve it as an authoritative server. From the point of view
  20420. of a resolver, there is no difference between master and slave.
  20421. The following data types are used to configure the Knot DNS server:
  20422. @end deffn
  20423. @deftp {Data Type} knot-key-configuration
  20424. Data type representing a key.
  20425. This type has the following parameters:
  20426. @table @asis
  20427. @item @code{id} (default: @code{""})
  20428. An identifier for other configuration fields to refer to this key. IDs must
  20429. be unique and must not be empty.
  20430. @item @code{algorithm} (default: @code{#f})
  20431. The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
  20432. @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
  20433. and @code{'hmac-sha512}.
  20434. @item @code{secret} (default: @code{""})
  20435. The secret key itself.
  20436. @end table
  20437. @end deftp
  20438. @deftp {Data Type} knot-acl-configuration
  20439. Data type representing an Access Control List (ACL) configuration.
  20440. This type has the following parameters:
  20441. @table @asis
  20442. @item @code{id} (default: @code{""})
  20443. An identifier for other configuration fields to refer to this key. IDs must be
  20444. unique and must not be empty.
  20445. @item @code{address} (default: @code{'()})
  20446. An ordered list of IP addresses, network subnets, or network ranges represented
  20447. with strings. The query must match one of them. Empty value means that
  20448. address match is not required.
  20449. @item @code{key} (default: @code{'()})
  20450. An ordered list of references to keys represented with strings. The string
  20451. must match a key ID defined in a @code{knot-key-configuration}. No key means
  20452. that a key is not require to match that ACL.
  20453. @item @code{action} (default: @code{'()})
  20454. An ordered list of actions that are permitted or forbidden by this ACL@. Possible
  20455. values are lists of zero or more elements from @code{'transfer}, @code{'notify}
  20456. and @code{'update}.
  20457. @item @code{deny?} (default: @code{#f})
  20458. When true, the ACL defines restrictions. Listed actions are forbidden. When
  20459. false, listed actions are allowed.
  20460. @end table
  20461. @end deftp
  20462. @deftp {Data Type} zone-entry
  20463. Data type representing a record entry in a zone file.
  20464. This type has the following parameters:
  20465. @table @asis
  20466. @item @code{name} (default: @code{"@@"})
  20467. The name of the record. @code{"@@"} refers to the origin of the zone. Names
  20468. are relative to the origin of the zone. For example, in the @code{example.org}
  20469. zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
  20470. Names ending with a dot are absolute, which means that @code{"ns.example.org."}
  20471. refers to @code{ns.example.org}.
  20472. @item @code{ttl} (default: @code{""})
  20473. The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
  20474. @item @code{class} (default: @code{"IN"})
  20475. The class of the record. Knot currently supports only @code{"IN"} and
  20476. partially @code{"CH"}.
  20477. @item @code{type} (default: @code{"A"})
  20478. The type of the record. Common types include A (IPv4 address), AAAA (IPv6
  20479. address), NS (Name Server) and MX (Mail eXchange). Many other types are
  20480. defined.
  20481. @item @code{data} (default: @code{""})
  20482. The data contained in the record. For instance an IP address associated with
  20483. an A record, or a domain name associated with an NS record. Remember that
  20484. domain names are relative to the origin unless they end with a dot.
  20485. @end table
  20486. @end deftp
  20487. @deftp {Data Type} zone-file
  20488. Data type representing the content of a zone file.
  20489. This type has the following parameters:
  20490. @table @asis
  20491. @item @code{entries} (default: @code{'()})
  20492. The list of entries. The SOA record is taken care of, so you don't need to
  20493. put it in the list of entries. This list should probably contain an entry
  20494. for your primary authoritative DNS server. Other than using a list of entries
  20495. directly, you can use @code{define-zone-entries} to define a object containing
  20496. the list of entries more easily, that you can later pass to the @code{entries}
  20497. field of the @code{zone-file}.
  20498. @item @code{origin} (default: @code{""})
  20499. The name of your zone. This parameter cannot be empty.
  20500. @item @code{ns} (default: @code{"ns"})
  20501. The domain of your primary authoritative DNS server. The name is relative to
  20502. the origin, unless it ends with a dot. It is mandatory that this primary
  20503. DNS server corresponds to an NS record in the zone and that it is associated
  20504. to an IP address in the list of entries.
  20505. @item @code{mail} (default: @code{"hostmaster"})
  20506. An email address people can contact you at, as the owner of the zone. This
  20507. is translated as @code{<mail>@@<origin>}.
  20508. @item @code{serial} (default: @code{1})
  20509. The serial number of the zone. As this is used to keep track of changes by
  20510. both slaves and resolvers, it is mandatory that it @emph{never} decreases.
  20511. Always increment it when you make a change in your zone.
  20512. @item @code{refresh} (default: @code{(* 2 24 3600)})
  20513. The frequency at which slaves will do a zone transfer. This value is a number
  20514. of seconds. It can be computed by multiplications or with
  20515. @code{(string->duration)}.
  20516. @item @code{retry} (default: @code{(* 15 60)})
  20517. The period after which a slave will retry to contact its master when it fails
  20518. to do so a first time.
  20519. @item @code{expiry} (default: @code{(* 14 24 3600)})
  20520. Default TTL of records. Existing records are considered correct for at most
  20521. this amount of time. After this period, resolvers will invalidate their cache
  20522. and check again that it still exists.
  20523. @item @code{nx} (default: @code{3600})
  20524. Default TTL of inexistant records. This delay is usually short because you want
  20525. your new domains to reach everyone quickly.
  20526. @end table
  20527. @end deftp
  20528. @deftp {Data Type} knot-remote-configuration
  20529. Data type representing a remote configuration.
  20530. This type has the following parameters:
  20531. @table @asis
  20532. @item @code{id} (default: @code{""})
  20533. An identifier for other configuration fields to refer to this remote. IDs must
  20534. be unique and must not be empty.
  20535. @item @code{address} (default: @code{'()})
  20536. An ordered list of destination IP addresses. Addresses are tried in sequence.
  20537. An optional port can be given with the @@ separator. For instance:
  20538. @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
  20539. @item @code{via} (default: @code{'()})
  20540. An ordered list of source IP addresses. An empty list will have Knot choose
  20541. an appropriate source IP@. An optional port can be given with the @@ separator.
  20542. The default is to choose at random.
  20543. @item @code{key} (default: @code{#f})
  20544. A reference to a key, that is a string containing the identifier of a key
  20545. defined in a @code{knot-key-configuration} field.
  20546. @end table
  20547. @end deftp
  20548. @deftp {Data Type} knot-keystore-configuration
  20549. Data type representing a keystore to hold dnssec keys.
  20550. This type has the following parameters:
  20551. @table @asis
  20552. @item @code{id} (default: @code{""})
  20553. The id of the keystore. It must not be empty.
  20554. @item @code{backend} (default: @code{'pem})
  20555. The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
  20556. @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
  20557. The configuration string of the backend. An example for the PKCS#11 is:
  20558. @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
  20559. For the pem backend, the string represents a path in the file system.
  20560. @end table
  20561. @end deftp
  20562. @deftp {Data Type} knot-policy-configuration
  20563. Data type representing a dnssec policy. Knot DNS is able to automatically
  20564. sign your zones. It can either generate and manage your keys automatically or
  20565. use keys that you generate.
  20566. Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
  20567. used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
  20568. zone. In order to be trusted, the KSK needs to be present in the parent zone
  20569. (usually a top-level domain). If your registrar supports dnssec, you will
  20570. have to send them your KSK's hash so they can add a DS record in their zone.
  20571. This is not automated and need to be done each time you change your KSK.
  20572. The policy also defines the lifetime of keys. Usually, ZSK can be changed
  20573. easily and use weaker cryptographic functions (they use lower parameters) in
  20574. order to sign records quickly, so they are changed often. The KSK however
  20575. requires manual interaction with the registrar, so they are changed less often
  20576. and use stronger parameters because they sign only one record.
  20577. This type has the following parameters:
  20578. @table @asis
  20579. @item @code{id} (default: @code{""})
  20580. The id of the policy. It must not be empty.
  20581. @item @code{keystore} (default: @code{"default"})
  20582. A reference to a keystore, that is a string containing the identifier of a
  20583. keystore defined in a @code{knot-keystore-configuration} field. The
  20584. @code{"default"} identifier means the default keystore (a kasp database that
  20585. was setup by this service).
  20586. @item @code{manual?} (default: @code{#f})
  20587. Whether the key management is manual or automatic.
  20588. @item @code{single-type-signing?} (default: @code{#f})
  20589. When @code{#t}, use the Single-Type Signing Scheme.
  20590. @item @code{algorithm} (default: @code{"ecdsap256sha256"})
  20591. An algorithm of signing keys and issued signatures.
  20592. @item @code{ksk-size} (default: @code{256})
  20593. The length of the KSK@. Note that this value is correct for the default
  20594. algorithm, but would be unsecure for other algorithms.
  20595. @item @code{zsk-size} (default: @code{256})
  20596. The length of the ZSK@. Note that this value is correct for the default
  20597. algorithm, but would be unsecure for other algorithms.
  20598. @item @code{dnskey-ttl} (default: @code{'default})
  20599. The TTL value for DNSKEY records added into zone apex. The special
  20600. @code{'default} value means same as the zone SOA TTL.
  20601. @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
  20602. The period between ZSK publication and the next rollover initiation.
  20603. @item @code{propagation-delay} (default: @code{(* 24 3600)})
  20604. An extra delay added for each key rollover step. This value should be high
  20605. enough to cover propagation of data from the master server to all slaves.
  20606. @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
  20607. A validity period of newly issued signatures.
  20608. @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
  20609. A period how long before a signature expiration the signature will be refreshed.
  20610. @item @code{nsec3?} (default: @code{#f})
  20611. When @code{#t}, NSEC3 will be used instead of NSEC.
  20612. @item @code{nsec3-iterations} (default: @code{5})
  20613. The number of additional times the hashing is performed.
  20614. @item @code{nsec3-salt-length} (default: @code{8})
  20615. The length of a salt field in octets, which is appended to the original owner
  20616. name before hashing.
  20617. @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
  20618. The validity period of newly issued salt field.
  20619. @end table
  20620. @end deftp
  20621. @deftp {Data Type} knot-zone-configuration
  20622. Data type representing a zone served by Knot.
  20623. This type has the following parameters:
  20624. @table @asis
  20625. @item @code{domain} (default: @code{""})
  20626. The domain served by this configuration. It must not be empty.
  20627. @item @code{file} (default: @code{""})
  20628. The file where this zone is saved. This parameter is ignored by master zones.
  20629. Empty means default location that depends on the domain name.
  20630. @item @code{zone} (default: @code{(zone-file)})
  20631. The content of the zone file. This parameter is ignored by slave zones. It
  20632. must contain a zone-file record.
  20633. @item @code{master} (default: @code{'()})
  20634. A list of master remotes. When empty, this zone is a master. When set, this
  20635. zone is a slave. This is a list of remotes identifiers.
  20636. @item @code{ddns-master} (default: @code{#f})
  20637. The main master. When empty, it defaults to the first master in the list of
  20638. masters.
  20639. @item @code{notify} (default: @code{'()})
  20640. A list of slave remote identifiers.
  20641. @item @code{acl} (default: @code{'()})
  20642. A list of acl identifiers.
  20643. @item @code{semantic-checks?} (default: @code{#f})
  20644. When set, this adds more semantic checks to the zone.
  20645. @item @code{disable-any?} (default: @code{#f})
  20646. When set, this forbids queries of the ANY type.
  20647. @item @code{zonefile-sync} (default: @code{0})
  20648. The delay between a modification in memory and on disk. 0 means immediate
  20649. synchronization.
  20650. @item @code{zonefile-load} (default: @code{#f})
  20651. The way the zone file contents are applied during zone load. Possible values
  20652. are:
  20653. @itemize
  20654. @item @code{#f} for using the default value from Knot,
  20655. @item @code{'none} for not using the zone file at all,
  20656. @item @code{'difference} for computing the difference between already available
  20657. contents and zone contents and applying it to the current zone contents,
  20658. @item @code{'difference-no-serial} for the same as @code{'difference}, but
  20659. ignoring the SOA serial in the zone file, while the server takes care of it
  20660. automatically.
  20661. @item @code{'whole} for loading zone contents from the zone file.
  20662. @end itemize
  20663. @item @code{journal-content} (default: @code{#f})
  20664. The way the journal is used to store zone and its changes. Possible values
  20665. are @code{'none} to not use it at all, @code{'changes} to store changes and
  20666. @code{'all} to store contents. @code{#f} does not set this option, so the
  20667. default value from Knot is used.
  20668. @item @code{max-journal-usage} (default: @code{#f})
  20669. The maximum size for the journal on disk. @code{#f} does not set this option,
  20670. so the default value from Knot is used.
  20671. @item @code{max-journal-depth} (default: @code{#f})
  20672. The maximum size of the history. @code{#f} does not set this option, so the
  20673. default value from Knot is used.
  20674. @item @code{max-zone-size} (default: @code{#f})
  20675. The maximum size of the zone file. This limit is enforced for incoming
  20676. transfer and updates. @code{#f} does not set this option, so the default
  20677. value from Knot is used.
  20678. @item @code{dnssec-policy} (default: @code{#f})
  20679. A reference to a @code{knot-policy-configuration} record, or the special
  20680. name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
  20681. on this zone.
  20682. @item @code{serial-policy} (default: @code{'increment})
  20683. A policy between @code{'increment} and @code{'unixtime}.
  20684. @end table
  20685. @end deftp
  20686. @deftp {Data Type} knot-configuration
  20687. Data type representing the Knot configuration.
  20688. This type has the following parameters:
  20689. @table @asis
  20690. @item @code{knot} (default: @code{knot})
  20691. The Knot package.
  20692. @item @code{run-directory} (default: @code{"/var/run/knot"})
  20693. The run directory. This directory will be used for pid file and sockets.
  20694. @item @code{includes} (default: @code{'()})
  20695. A list of strings or file-like objects denoting other files that must be
  20696. included at the top of the configuration file.
  20697. @cindex secrets, Knot service
  20698. This can be used to manage secrets out-of-band. For example, secret
  20699. keys may be stored in an out-of-band file not managed by Guix, and
  20700. thus not visible in @file{/gnu/store}---e.g., you could store secret
  20701. key configuration in @file{/etc/knot/secrets.conf} and add this file
  20702. to the @code{includes} list.
  20703. One can generate a secret tsig key (for nsupdate and zone transfers with the
  20704. keymgr command from the knot package. Note that the package is not automatically
  20705. installed by the service. The following example shows how to generate a new
  20706. tsig key:
  20707. @example
  20708. keymgr -t mysecret > /etc/knot/secrets.conf
  20709. chmod 600 /etc/knot/secrets.conf
  20710. @end example
  20711. Also note that the generated key will be named @var{mysecret}, so it is the
  20712. name that needs to be used in the @var{key} field of the
  20713. @code{knot-acl-configuration} record and in other places that need to refer
  20714. to that key.
  20715. It can also be used to add configuration not supported by this interface.
  20716. @item @code{listen-v4} (default: @code{"0.0.0.0"})
  20717. An ip address on which to listen.
  20718. @item @code{listen-v6} (default: @code{"::"})
  20719. An ip address on which to listen.
  20720. @item @code{listen-port} (default: @code{53})
  20721. A port on which to listen.
  20722. @item @code{keys} (default: @code{'()})
  20723. The list of knot-key-configuration used by this configuration.
  20724. @item @code{acls} (default: @code{'()})
  20725. The list of knot-acl-configuration used by this configuration.
  20726. @item @code{remotes} (default: @code{'()})
  20727. The list of knot-remote-configuration used by this configuration.
  20728. @item @code{zones} (default: @code{'()})
  20729. The list of knot-zone-configuration used by this configuration.
  20730. @end table
  20731. @end deftp
  20732. @subsubheading Knot Resolver Service
  20733. @deffn {Scheme Variable} knot-resolver-service-type
  20734. This is the type of the knot resolver service, whose value should be
  20735. an @code{knot-resolver-configuration} object as in this example:
  20736. @lisp
  20737. (service knot-resolver-service-type
  20738. (knot-resolver-configuration
  20739. (kresd-config-file (plain-file "kresd.conf" "
  20740. net.listen('192.168.0.1', 5353)
  20741. user('knot-resolver', 'knot-resolver')
  20742. modules = @{ 'hints > iterate', 'stats', 'predict' @}
  20743. cache.size = 100 * MB
  20744. "))))
  20745. @end lisp
  20746. For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
  20747. @end deffn
  20748. @deftp {Data Type} knot-resolver-configuration
  20749. Data type representing the configuration of knot-resolver.
  20750. @table @asis
  20751. @item @code{package} (default: @var{knot-resolver})
  20752. Package object of the knot DNS resolver.
  20753. @item @code{kresd-config-file} (default: %kresd.conf)
  20754. File-like object of the kresd configuration file to use, by default it
  20755. will listen on @code{127.0.0.1} and @code{::1}.
  20756. @item @code{garbage-collection-interval} (default: 1000)
  20757. Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
  20758. @end table
  20759. @end deftp
  20760. @subsubheading Dnsmasq Service
  20761. @deffn {Scheme Variable} dnsmasq-service-type
  20762. This is the type of the dnsmasq service, whose value should be an
  20763. @code{dnsmasq-configuration} object as in this example:
  20764. @lisp
  20765. (service dnsmasq-service-type
  20766. (dnsmasq-configuration
  20767. (no-resolv? #t)
  20768. (servers '("192.168.1.1"))))
  20769. @end lisp
  20770. @end deffn
  20771. @deftp {Data Type} dnsmasq-configuration
  20772. Data type representing the configuration of dnsmasq.
  20773. @table @asis
  20774. @item @code{package} (default: @var{dnsmasq})
  20775. Package object of the dnsmasq server.
  20776. @item @code{no-hosts?} (default: @code{#f})
  20777. When true, don't read the hostnames in /etc/hosts.
  20778. @item @code{port} (default: @code{53})
  20779. The port to listen on. Setting this to zero completely disables DNS
  20780. responses, leaving only DHCP and/or TFTP functions.
  20781. @item @code{local-service?} (default: @code{#t})
  20782. Accept DNS queries only from hosts whose address is on a local subnet,
  20783. ie a subnet for which an interface exists on the server.
  20784. @item @code{listen-addresses} (default: @code{'()})
  20785. Listen on the given IP addresses.
  20786. @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
  20787. The file to read the IP address of the upstream nameservers from.
  20788. @item @code{no-resolv?} (default: @code{#f})
  20789. When true, don't read @var{resolv-file}.
  20790. @item @code{servers} (default: @code{'()})
  20791. Specify IP address of upstream servers directly.
  20792. @item @code{addresses} (default: @code{'()})
  20793. For each entry, specify an IP address to return for any host in the
  20794. given domains. Queries in the domains are never forwarded and always
  20795. replied to with the specified IP address.
  20796. This is useful for redirecting hosts locally, for example:
  20797. @lisp
  20798. (service dnsmasq-service-type
  20799. (dnsmasq-configuration
  20800. (addresses
  20801. '(; Redirect to a local web-server.
  20802. "/example.org/127.0.0.1"
  20803. ; Redirect subdomain to a specific IP.
  20804. "/subdomain.example.org/192.168.1.42"))))
  20805. @end lisp
  20806. Note that rules in @file{/etc/hosts} take precedence over this.
  20807. @item @code{cache-size} (default: @code{150})
  20808. Set the size of dnsmasq's cache. Setting the cache size to zero
  20809. disables caching.
  20810. @item @code{negative-cache?} (default: @code{#t})
  20811. When false, disable negative caching.
  20812. @item @code{tftp-enable?} (default: @code{#f})
  20813. Whether to enable the built-in TFTP server.
  20814. @item @code{tftp-no-fail?} (default: @code{#f})
  20815. If true, does not fail dnsmasq if the TFTP server could not start up.
  20816. @item @code{tftp-single-port?} (default: @code{#f})
  20817. Whether to use only one single port for TFTP.
  20818. @item @code{tftp-secure?} (default: @code{#f})
  20819. If true, only files owned by the user running the dnsmasq process are accessible.
  20820. If dnsmasq is being run as root, different rules apply:
  20821. @code{tftp-secure?} has no effect, but only files which have the
  20822. world-readable bit set are accessible.
  20823. @item @code{tftp-max} (default: @code{#f})
  20824. If set, sets the maximal number of concurrent connections allowed.
  20825. @item @code{tftp-mtu} (default: @code{#f})
  20826. If set, sets the MTU for TFTP packets to that value.
  20827. @item @code{tftp-no-blocksize?} (default: @code{#f})
  20828. If true, stops the TFTP server from negotiating the blocksize with a client.
  20829. @item @code{tftp-lowercase?} (default: @code{#f})
  20830. Whether to convert all filenames in TFTP requests to lowercase.
  20831. @item @code{tftp-port-range} (default: @code{#f})
  20832. If set, fixes the dynamical ports (one per client) to the given range
  20833. (@code{"<start>,<end>"}).
  20834. @item @code{tftp-root} (default: @code{/var/empty,lo})
  20835. Look for files to transfer using TFTP relative to the given directory.
  20836. When this is set, TFTP paths which include @samp{..} are rejected, to stop clients
  20837. getting outside the specified root. Absolute paths (starting with @samp{/}) are
  20838. allowed, but they must be within the TFTP-root. If the optional interface
  20839. argument is given, the directory is only used for TFTP requests via that
  20840. interface.
  20841. @item @code{tftp-unique-root} (default: @code{#f})
  20842. If set, add the IP or hardware address of the TFTP client as a path component
  20843. on the end of the TFTP-root. Only valid if a TFTP root is set and the
  20844. directory exists. Defaults to adding IP address (in standard dotted-quad
  20845. format).
  20846. For instance, if @option{--tftp-root} is @samp{/tftp} and client
  20847. @samp{1.2.3.4} requests file @file{myfile} then the effective path will
  20848. be @file{/tftp/1.2.3.4/myfile} if @file{/tftp/1.2.3.4} exists or
  20849. @file{/tftp/myfile} otherwise. When @samp{=mac} is specified it will
  20850. append the MAC address instead, using lowercase zero padded digits
  20851. separated by dashes, e.g.: @samp{01-02-03-04-aa-bb}. Note that
  20852. resolving MAC addresses is only possible if the client is in the local
  20853. network or obtained a DHCP lease from dnsmasq.
  20854. @end table
  20855. @end deftp
  20856. @subsubheading ddclient Service
  20857. @cindex ddclient
  20858. The ddclient service described below runs the ddclient daemon, which takes
  20859. care of automatically updating DNS entries for service providers such as
  20860. @uref{https://dyn.com/dns/, Dyn}.
  20861. The following example show instantiates the service with its default
  20862. configuration:
  20863. @lisp
  20864. (service ddclient-service-type)
  20865. @end lisp
  20866. Note that ddclient needs to access credentials that are stored in a
  20867. @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
  20868. @code{secret-file} below). You are expected to create this file manually, in
  20869. an ``out-of-band'' fashion (you @emph{could} make this file part of the
  20870. service configuration, for instance by using @code{plain-file}, but it will be
  20871. world-readable @i{via} @file{/gnu/store}). See the examples in the
  20872. @file{share/ddclient} directory of the @code{ddclient} package.
  20873. @c %start of fragment
  20874. Available @code{ddclient-configuration} fields are:
  20875. @deftypevr {@code{ddclient-configuration} parameter} package ddclient
  20876. The ddclient package.
  20877. @end deftypevr
  20878. @deftypevr {@code{ddclient-configuration} parameter} integer daemon
  20879. The period after which ddclient will retry to check IP and domain name.
  20880. Defaults to @samp{300}.
  20881. @end deftypevr
  20882. @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
  20883. Use syslog for the output.
  20884. Defaults to @samp{#t}.
  20885. @end deftypevr
  20886. @deftypevr {@code{ddclient-configuration} parameter} string mail
  20887. Mail to user.
  20888. Defaults to @samp{"root"}.
  20889. @end deftypevr
  20890. @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
  20891. Mail failed update to user.
  20892. Defaults to @samp{"root"}.
  20893. @end deftypevr
  20894. @deftypevr {@code{ddclient-configuration} parameter} string pid
  20895. The ddclient PID file.
  20896. Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
  20897. @end deftypevr
  20898. @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
  20899. Enable SSL support.
  20900. Defaults to @samp{#t}.
  20901. @end deftypevr
  20902. @deftypevr {@code{ddclient-configuration} parameter} string user
  20903. Specifies the user name or ID that is used when running ddclient
  20904. program.
  20905. Defaults to @samp{"ddclient"}.
  20906. @end deftypevr
  20907. @deftypevr {@code{ddclient-configuration} parameter} string group
  20908. Group of the user who will run the ddclient program.
  20909. Defaults to @samp{"ddclient"}.
  20910. @end deftypevr
  20911. @deftypevr {@code{ddclient-configuration} parameter} string secret-file
  20912. Secret file which will be appended to @file{ddclient.conf} file. This
  20913. file contains credentials for use by ddclient. You are expected to
  20914. create it manually.
  20915. Defaults to @samp{"/etc/ddclient/secrets.conf"}.
  20916. @end deftypevr
  20917. @deftypevr {@code{ddclient-configuration} parameter} list extra-options
  20918. Extra options will be appended to @file{ddclient.conf} file.
  20919. Defaults to @samp{()}.
  20920. @end deftypevr
  20921. @c %end of fragment
  20922. @node VPN Services
  20923. @subsection VPN Services
  20924. @cindex VPN (virtual private network)
  20925. @cindex virtual private network (VPN)
  20926. The @code{(gnu services vpn)} module provides services related to
  20927. @dfn{virtual private networks} (VPNs).
  20928. @subsubheading OpenVPN
  20929. It provides a @emph{client} service for your machine to connect to a
  20930. VPN, and a @emph{server} service for your machine to host a VPN@.
  20931. @deffn {Scheme Procedure} openvpn-client-service @
  20932. [#:config (openvpn-client-configuration)]
  20933. Return a service that runs @command{openvpn}, a VPN daemon, as a client.
  20934. @end deffn
  20935. @deffn {Scheme Procedure} openvpn-server-service @
  20936. [#:config (openvpn-server-configuration)]
  20937. Return a service that runs @command{openvpn}, a VPN daemon, as a server.
  20938. Both can be run simultaneously.
  20939. @end deffn
  20940. @c %automatically generated documentation
  20941. Available @code{openvpn-client-configuration} fields are:
  20942. @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
  20943. The OpenVPN package.
  20944. @end deftypevr
  20945. @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
  20946. The OpenVPN pid file.
  20947. Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
  20948. @end deftypevr
  20949. @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
  20950. The protocol (UDP or TCP) used to open a channel between clients and
  20951. servers.
  20952. Defaults to @samp{udp}.
  20953. @end deftypevr
  20954. @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
  20955. The device type used to represent the VPN connection.
  20956. Defaults to @samp{tun}.
  20957. @end deftypevr
  20958. If you do not have some of these files (eg.@: you use a username and
  20959. password), you can disable any of the following three fields by setting
  20960. it to @code{'disabled}.
  20961. @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string ca
  20962. The certificate authority to check connections against.
  20963. Defaults to @samp{"/etc/openvpn/ca.crt"}.
  20964. @end deftypevr
  20965. @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string cert
  20966. The certificate of the machine the daemon is running on. It should be
  20967. signed by the authority given in @code{ca}.
  20968. Defaults to @samp{"/etc/openvpn/client.crt"}.
  20969. @end deftypevr
  20970. @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string key
  20971. The key of the machine the daemon is running on. It must be the key whose
  20972. certificate is @code{cert}.
  20973. Defaults to @samp{"/etc/openvpn/client.key"}.
  20974. @end deftypevr
  20975. @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
  20976. Whether to use the lzo compression algorithm.
  20977. Defaults to @samp{#t}.
  20978. @end deftypevr
  20979. @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
  20980. Don't re-read key files across SIGUSR1 or --ping-restart.
  20981. Defaults to @samp{#t}.
  20982. @end deftypevr
  20983. @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
  20984. Don't close and reopen TUN/TAP device or run up/down scripts across
  20985. SIGUSR1 or --ping-restart restarts.
  20986. Defaults to @samp{#t}.
  20987. @end deftypevr
  20988. @deftypevr {@code{openvpn-client-configuration} parameter} boolean fast-io?
  20989. (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
  20990. poll/epoll/select prior to the write operation.
  20991. Defaults to @samp{#f}.
  20992. @end deftypevr
  20993. @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
  20994. Verbosity level.
  20995. Defaults to @samp{3}.
  20996. @end deftypevr
  20997. @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
  20998. Add an additional layer of HMAC authentication on top of the TLS control
  20999. channel to protect against DoS attacks.
  21000. Defaults to @samp{#f}.
  21001. @end deftypevr
  21002. @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string auth-user-pass
  21003. Authenticate with server using username/password. The option is a file
  21004. containing username/password on 2 lines. Do not use a file-like object as it
  21005. would be added to the store and readable by any user.
  21006. Defaults to @samp{'disabled}.
  21007. @end deftypevr
  21008. @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
  21009. Whether to check the server certificate has server usage extension.
  21010. Defaults to @samp{#t}.
  21011. @end deftypevr
  21012. @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
  21013. Bind to a specific local port number.
  21014. Defaults to @samp{#f}.
  21015. @end deftypevr
  21016. @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
  21017. Retry resolving server address.
  21018. Defaults to @samp{#t}.
  21019. @end deftypevr
  21020. @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
  21021. A list of remote servers to connect to.
  21022. Defaults to @samp{()}.
  21023. Available @code{openvpn-remote-configuration} fields are:
  21024. @deftypevr {@code{openvpn-remote-configuration} parameter} string name
  21025. Server name.
  21026. Defaults to @samp{"my-server"}.
  21027. @end deftypevr
  21028. @deftypevr {@code{openvpn-remote-configuration} parameter} number port
  21029. Port number the server listens to.
  21030. Defaults to @samp{1194}.
  21031. @end deftypevr
  21032. @end deftypevr
  21033. @c %end of automatic openvpn-client documentation
  21034. @c %automatically generated documentation
  21035. Available @code{openvpn-server-configuration} fields are:
  21036. @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
  21037. The OpenVPN package.
  21038. @end deftypevr
  21039. @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
  21040. The OpenVPN pid file.
  21041. Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
  21042. @end deftypevr
  21043. @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
  21044. The protocol (UDP or TCP) used to open a channel between clients and
  21045. servers.
  21046. Defaults to @samp{udp}.
  21047. @end deftypevr
  21048. @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
  21049. The device type used to represent the VPN connection.
  21050. Defaults to @samp{tun}.
  21051. @end deftypevr
  21052. If you do not have some of these files (eg.@: you use a username and
  21053. password), you can disable any of the following three fields by setting
  21054. it to @code{'disabled}.
  21055. @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string ca
  21056. The certificate authority to check connections against.
  21057. Defaults to @samp{"/etc/openvpn/ca.crt"}.
  21058. @end deftypevr
  21059. @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string cert
  21060. The certificate of the machine the daemon is running on. It should be
  21061. signed by the authority given in @code{ca}.
  21062. Defaults to @samp{"/etc/openvpn/client.crt"}.
  21063. @end deftypevr
  21064. @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string key
  21065. The key of the machine the daemon is running on. It must be the key whose
  21066. certificate is @code{cert}.
  21067. Defaults to @samp{"/etc/openvpn/client.key"}.
  21068. @end deftypevr
  21069. @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
  21070. Whether to use the lzo compression algorithm.
  21071. Defaults to @samp{#t}.
  21072. @end deftypevr
  21073. @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
  21074. Don't re-read key files across SIGUSR1 or --ping-restart.
  21075. Defaults to @samp{#t}.
  21076. @end deftypevr
  21077. @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
  21078. Don't close and reopen TUN/TAP device or run up/down scripts across
  21079. SIGUSR1 or --ping-restart restarts.
  21080. Defaults to @samp{#t}.
  21081. @end deftypevr
  21082. @deftypevr {@code{openvpn-server-configuration} parameter} boolean fast-io?
  21083. (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
  21084. poll/epoll/select prior to the write operation.
  21085. Defaults to @samp{#f}.
  21086. @end deftypevr
  21087. @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
  21088. Verbosity level.
  21089. Defaults to @samp{3}.
  21090. @end deftypevr
  21091. @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
  21092. Add an additional layer of HMAC authentication on top of the TLS control
  21093. channel to protect against DoS attacks.
  21094. Defaults to @samp{#f}.
  21095. @end deftypevr
  21096. @deftypevr {@code{openvpn-server-configuration} parameter} number port
  21097. Specifies the port number on which the server listens.
  21098. Defaults to @samp{1194}.
  21099. @end deftypevr
  21100. @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
  21101. An ip and mask specifying the subnet inside the virtual network.
  21102. Defaults to @samp{"10.8.0.0 255.255.255.0"}.
  21103. @end deftypevr
  21104. @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
  21105. A CIDR notation specifying the IPv6 subnet inside the virtual network.
  21106. Defaults to @samp{#f}.
  21107. @end deftypevr
  21108. @deftypevr {@code{openvpn-server-configuration} parameter} string dh
  21109. The Diffie-Hellman parameters file.
  21110. Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
  21111. @end deftypevr
  21112. @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
  21113. The file that records client IPs.
  21114. Defaults to @samp{"/etc/openvpn/ipp.txt"}.
  21115. @end deftypevr
  21116. @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
  21117. When true, the server will act as a gateway for its clients.
  21118. Defaults to @samp{#f}.
  21119. @end deftypevr
  21120. @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
  21121. When true, clients are allowed to talk to each other inside the VPN.
  21122. Defaults to @samp{#f}.
  21123. @end deftypevr
  21124. @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
  21125. Causes ping-like messages to be sent back and forth over the link so
  21126. that each side knows when the other side has gone down. @code{keepalive}
  21127. requires a pair. The first element is the period of the ping sending,
  21128. and the second element is the timeout before considering the other side
  21129. down.
  21130. @end deftypevr
  21131. @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
  21132. The maximum number of clients.
  21133. Defaults to @samp{100}.
  21134. @end deftypevr
  21135. @deftypevr {@code{openvpn-server-configuration} parameter} string status
  21136. The status file. This file shows a small report on current connection.
  21137. It is truncated and rewritten every minute.
  21138. Defaults to @samp{"/var/run/openvpn/status"}.
  21139. @end deftypevr
  21140. @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
  21141. The list of configuration for some clients.
  21142. Defaults to @samp{()}.
  21143. Available @code{openvpn-ccd-configuration} fields are:
  21144. @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
  21145. Client name.
  21146. Defaults to @samp{"client"}.
  21147. @end deftypevr
  21148. @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
  21149. Client own network
  21150. Defaults to @samp{#f}.
  21151. @end deftypevr
  21152. @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
  21153. Client VPN IP.
  21154. Defaults to @samp{#f}.
  21155. @end deftypevr
  21156. @end deftypevr
  21157. @c %end of automatic openvpn-server documentation
  21158. @subsubheading Wireguard
  21159. @defvr {Scheme Variable} wireguard-service-type
  21160. A service type for a Wireguard tunnel interface. Its value must be a
  21161. @code{wireguard-configuration} record as in this example:
  21162. @lisp
  21163. (service wireguard-service-type
  21164. (wireguard-configuration
  21165. (peers
  21166. (list
  21167. (wireguard-peer
  21168. (name "my-peer")
  21169. (endpoint "my.wireguard.com:51820")
  21170. (public-key "hzpKg9X1yqu1axN6iJp0mWf6BZGo8m1wteKwtTmDGF4=")
  21171. (allowed-ips '("10.0.0.2/32")))))))
  21172. @end lisp
  21173. @end defvr
  21174. @deftp {Data Type} wireguard-configuration
  21175. Data type representing the configuration of the Wireguard service.
  21176. @table @asis
  21177. @item @code{wireguard}
  21178. The wireguard package to use for this service.
  21179. @item @code{interface} (default: @code{"wg0"})
  21180. The interface name for the VPN.
  21181. @item @code{addresses} (default: @code{'("10.0.0.1/32")})
  21182. The IP addresses to be assigned to the above interface.
  21183. @item @code{private-key} (default: @code{"/etc/wireguard/private.key"})
  21184. The private key file for the interface. It is automatically generated if
  21185. the file does not exist.
  21186. @item @code{peers} (default: @code{'()})
  21187. The authorized peers on this interface. This is a list of
  21188. @var{wireguard-peer} records.
  21189. @end table
  21190. @end deftp
  21191. @deftp {Data Type} wireguard-peer
  21192. Data type representing a Wireguard peer attached to a given interface.
  21193. @table @asis
  21194. @item @code{name}
  21195. The peer name.
  21196. @item @code{endpoint} (default: @code{#f})
  21197. The optional endpoint for the peer, such as
  21198. @code{"demo.wireguard.com:51820"}.
  21199. @item @code{public-key}
  21200. The peer public-key represented as a base64 string.
  21201. @item @code{allowed-ips}
  21202. A list of IP addresses from which incoming traffic for this peer is
  21203. allowed and to which incoming traffic for this peer is directed.
  21204. @end table
  21205. @end deftp
  21206. @node Network File System
  21207. @subsection Network File System
  21208. @cindex NFS
  21209. The @code{(gnu services nfs)} module provides the following services,
  21210. which are most commonly used in relation to mounting or exporting
  21211. directory trees as @dfn{network file systems} (NFS).
  21212. While it is possible to use the individual components that together make
  21213. up a Network File System service, we recommended to configure an NFS
  21214. server with the @code{nfs-service-type}.
  21215. @subsubheading NFS Service
  21216. @cindex NFS, server
  21217. The NFS service takes care of setting up all NFS component services,
  21218. kernel configuration file systems, and installs configuration files in
  21219. the locations that NFS expects.
  21220. @defvr {Scheme Variable} nfs-service-type
  21221. A service type for a complete NFS server.
  21222. @end defvr
  21223. @deftp {Data Type} nfs-configuration
  21224. This data type represents the configuration of the NFS service and all
  21225. of its subsystems.
  21226. It has the following parameters:
  21227. @table @asis
  21228. @item @code{nfs-utils} (default: @code{nfs-utils})
  21229. The nfs-utils package to use.
  21230. @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
  21231. If a list of string values is provided, the @command{rpc.nfsd} daemon
  21232. will be limited to supporting the given versions of the NFS protocol.
  21233. @item @code{exports} (default: @code{'()})
  21234. This is a list of directories the NFS server should export. Each entry
  21235. is a list consisting of two elements: a directory name and a string
  21236. containing all options. This is an example in which the directory
  21237. @file{/export} is served to all NFS clients as a read-only share:
  21238. @lisp
  21239. (nfs-configuration
  21240. (exports
  21241. '(("/export"
  21242. "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
  21243. @end lisp
  21244. @item @code{rpcmountd-port} (default: @code{#f})
  21245. The network port that the @command{rpc.mountd} daemon should use.
  21246. @item @code{rpcstatd-port} (default: @code{#f})
  21247. The network port that the @command{rpc.statd} daemon should use.
  21248. @item @code{rpcbind} (default: @code{rpcbind})
  21249. The rpcbind package to use.
  21250. @item @code{idmap-domain} (default: @code{"localdomain"})
  21251. The local NFSv4 domain name.
  21252. @item @code{nfsd-port} (default: @code{2049})
  21253. The network port that the @command{nfsd} daemon should use.
  21254. @item @code{nfsd-threads} (default: @code{8})
  21255. The number of threads used by the @command{nfsd} daemon.
  21256. @item @code{nfsd-tcp?} (default: @code{#t})
  21257. Whether the @command{nfsd} daemon should listen on a TCP socket.
  21258. @item @code{nfsd-udp?} (default: @code{#f})
  21259. Whether the @command{nfsd} daemon should listen on a UDP socket.
  21260. @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
  21261. The directory where the pipefs file system is mounted.
  21262. @item @code{debug} (default: @code{'()"})
  21263. A list of subsystems for which debugging output should be enabled. This
  21264. is a list of symbols. Any of these symbols are valid: @code{nfsd},
  21265. @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
  21266. @end table
  21267. @end deftp
  21268. If you don't need a complete NFS service or prefer to build it yourself
  21269. you can use the individual component services that are documented below.
  21270. @subsubheading RPC Bind Service
  21271. @cindex rpcbind
  21272. The RPC Bind service provides a facility to map program numbers into
  21273. universal addresses.
  21274. Many NFS related services use this facility. Hence it is automatically
  21275. started when a dependent service starts.
  21276. @defvr {Scheme Variable} rpcbind-service-type
  21277. A service type for the RPC portmapper daemon.
  21278. @end defvr
  21279. @deftp {Data Type} rpcbind-configuration
  21280. Data type representing the configuration of the RPC Bind Service.
  21281. This type has the following parameters:
  21282. @table @asis
  21283. @item @code{rpcbind} (default: @code{rpcbind})
  21284. The rpcbind package to use.
  21285. @item @code{warm-start?} (default: @code{#t})
  21286. If this parameter is @code{#t}, then the daemon will read a
  21287. state file on startup thus reloading state information saved by a previous
  21288. instance.
  21289. @end table
  21290. @end deftp
  21291. @subsubheading Pipefs Pseudo File System
  21292. @cindex pipefs
  21293. @cindex rpc_pipefs
  21294. The pipefs file system is used to transfer NFS related data
  21295. between the kernel and user space programs.
  21296. @defvr {Scheme Variable} pipefs-service-type
  21297. A service type for the pipefs pseudo file system.
  21298. @end defvr
  21299. @deftp {Data Type} pipefs-configuration
  21300. Data type representing the configuration of the pipefs pseudo file system service.
  21301. This type has the following parameters:
  21302. @table @asis
  21303. @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
  21304. The directory to which the file system is to be attached.
  21305. @end table
  21306. @end deftp
  21307. @subsubheading GSS Daemon Service
  21308. @cindex GSSD
  21309. @cindex GSS
  21310. @cindex global security system
  21311. The @dfn{global security system} (GSS) daemon provides strong security for RPC
  21312. based protocols.
  21313. Before exchanging RPC requests an RPC client must establish a security
  21314. context. Typically this is done using the Kerberos command @command{kinit}
  21315. or automatically at login time using PAM services (@pxref{Kerberos Services}).
  21316. @defvr {Scheme Variable} gss-service-type
  21317. A service type for the Global Security System (GSS) daemon.
  21318. @end defvr
  21319. @deftp {Data Type} gss-configuration
  21320. Data type representing the configuration of the GSS daemon service.
  21321. This type has the following parameters:
  21322. @table @asis
  21323. @item @code{nfs-utils} (default: @code{nfs-utils})
  21324. The package in which the @command{rpc.gssd} command is to be found.
  21325. @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
  21326. The directory where the pipefs file system is mounted.
  21327. @end table
  21328. @end deftp
  21329. @subsubheading IDMAP Daemon Service
  21330. @cindex idmapd
  21331. @cindex name mapper
  21332. The idmap daemon service provides mapping between user IDs and user names.
  21333. Typically it is required in order to access file systems mounted via NFSv4.
  21334. @defvr {Scheme Variable} idmap-service-type
  21335. A service type for the Identity Mapper (IDMAP) daemon.
  21336. @end defvr
  21337. @deftp {Data Type} idmap-configuration
  21338. Data type representing the configuration of the IDMAP daemon service.
  21339. This type has the following parameters:
  21340. @table @asis
  21341. @item @code{nfs-utils} (default: @code{nfs-utils})
  21342. The package in which the @command{rpc.idmapd} command is to be found.
  21343. @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
  21344. The directory where the pipefs file system is mounted.
  21345. @item @code{domain} (default: @code{#f})
  21346. The local NFSv4 domain name.
  21347. This must be a string or @code{#f}.
  21348. If it is @code{#f} then the daemon will use the host's fully qualified domain name.
  21349. @item @code{verbosity} (default: @code{0})
  21350. The verbosity level of the daemon.
  21351. @end table
  21352. @end deftp
  21353. @node Continuous Integration
  21354. @subsection Continuous Integration
  21355. @cindex continuous integration
  21356. @uref{https://guix.gnu.org/cuirass/, Cuirass} is a continuous
  21357. integration tool for Guix. It can be used both for development and for
  21358. providing substitutes to others (@pxref{Substitutes}).
  21359. The @code{(gnu services cuirass)} module provides the following service.
  21360. @defvr {Scheme Procedure} cuirass-service-type
  21361. The type of the Cuirass service. Its value must be a
  21362. @code{cuirass-configuration} object, as described below.
  21363. @end defvr
  21364. To add build jobs, you have to set the @code{specifications} field of
  21365. the configuration. For instance, the following example will build all
  21366. the packages provided by the @code{my-channel} channel.
  21367. @lisp
  21368. (define %cuirass-specs
  21369. #~(list (specification
  21370. (name "my-channel")
  21371. (build '(channels my-channel))
  21372. (channels
  21373. (cons (channel
  21374. (name 'my-channel)
  21375. (url "https://my-channel.git"))
  21376. %default-channels)))))
  21377. (service cuirass-service-type
  21378. (cuirass-configuration
  21379. (specifications %cuirass-specs)))
  21380. @end lisp
  21381. To build the @code{linux-libre} package defined by the default Guix
  21382. channel, one can use the following configuration.
  21383. @lisp
  21384. (define %cuirass-specs
  21385. #~(list (specification
  21386. (name "my-linux")
  21387. (build '(packages "linux-libre")))))
  21388. (service cuirass-service-type
  21389. (cuirass-configuration
  21390. (specifications %cuirass-specs)))
  21391. @end lisp
  21392. The other configuration possibilities, as well as the specification
  21393. record itself are described in the Cuirass manual
  21394. (@pxref{Specifications,,, cuirass, Cuirass}).
  21395. While information related to build jobs is located directly in the
  21396. specifications, global settings for the @command{cuirass} process are
  21397. accessible in other @code{cuirass-configuration} fields.
  21398. @deftp {Data Type} cuirass-configuration
  21399. Data type representing the configuration of Cuirass.
  21400. @table @asis
  21401. @item @code{cuirass} (default: @code{cuirass})
  21402. The Cuirass package to use.
  21403. @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
  21404. Location of the log file.
  21405. @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
  21406. Location of the log file used by the web interface.
  21407. @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
  21408. Location of the repository cache.
  21409. @item @code{user} (default: @code{"cuirass"})
  21410. Owner of the @code{cuirass} process.
  21411. @item @code{group} (default: @code{"cuirass"})
  21412. Owner's group of the @code{cuirass} process.
  21413. @item @code{interval} (default: @code{60})
  21414. Number of seconds between the poll of the repositories followed by the
  21415. Cuirass jobs.
  21416. @item @code{parameters} (default: @code{#f})
  21417. Read parameters from the given @var{parameters} file. The supported
  21418. parameters are described here (@pxref{Parameters,,, cuirass, Cuirass}).
  21419. @item @code{remote-server} (default: @code{#f})
  21420. A @code{cuirass-remote-server-configuration} record to use the build
  21421. remote mechanism or @code{#f} to use the default build mechanism.
  21422. @item @code{database} (default: @code{"dbname=cuirass host=/var/run/postgresql"})
  21423. Use @var{database} as the database containing the jobs and the past
  21424. build results. Since Cuirass uses PostgreSQL as a database engine,
  21425. @var{database} must be a string such as @code{"dbname=cuirass
  21426. host=localhost"}.
  21427. @item @code{port} (default: @code{8081})
  21428. Port number used by the HTTP server.
  21429. @item @code{host} (default: @code{"localhost"})
  21430. Listen on the network interface for @var{host}. The default is to
  21431. accept connections from localhost.
  21432. @item @code{specifications} (default: @code{#~'()})
  21433. A gexp (@pxref{G-Expressions}) that evaluates to a list of
  21434. specifications records. The specification record is described in the
  21435. Cuirass manual (@pxref{Specifications,,, cuirass, Cuirass}).
  21436. @item @code{use-substitutes?} (default: @code{#f})
  21437. This allows using substitutes to avoid building every dependencies of a job
  21438. from source.
  21439. @item @code{one-shot?} (default: @code{#f})
  21440. Only evaluate specifications and build derivations once.
  21441. @item @code{fallback?} (default: @code{#f})
  21442. When substituting a pre-built binary fails, fall back to building
  21443. packages locally.
  21444. @item @code{extra-options} (default: @code{'()})
  21445. Extra options to pass when running the Cuirass processes.
  21446. @end table
  21447. @end deftp
  21448. @cindex remote build
  21449. @subsubheading Cuirass remote building
  21450. Cuirass supports two mechanisms to build derivations.
  21451. @itemize
  21452. @item Using the local Guix daemon.
  21453. This is the default build mechanism. Once the build jobs are
  21454. evaluated, they are sent to the local Guix daemon. Cuirass then
  21455. listens to the Guix daemon output to detect the various build events.
  21456. @item Using the remote build mechanism.
  21457. The build jobs are not submitted to the local Guix daemon. Instead, a
  21458. remote server dispatches build requests to the connect remote workers,
  21459. according to the build priorities.
  21460. @end itemize
  21461. To enable this build mode a @code{cuirass-remote-server-configuration}
  21462. record must be passed as @code{remote-server} argument of the
  21463. @code{cuirass-configuration} record. The
  21464. @code{cuirass-remote-server-configuration} record is described below.
  21465. This build mode scales way better than the default build mode. This is
  21466. the build mode that is used on the GNU Guix build farm at
  21467. @url{https://ci.guix.gnu.org}. It should be preferred when using
  21468. Cuirass to build large amount of packages.
  21469. @deftp {Data Type} cuirass-remote-server-configuration
  21470. Data type representing the configuration of the Cuirass remote-server.
  21471. @table @asis
  21472. @item @code{backend-port} (default: @code{5555})
  21473. The TCP port for communicating with @code{remote-worker} processes
  21474. using ZMQ. It defaults to @code{5555}.
  21475. @item @code{log-port} (default: @code{5556})
  21476. The TCP port of the log server. It defaults to @code{5556}.
  21477. @item @code{publish-port} (default: @code{5557})
  21478. The TCP port of the publish server. It defaults to @code{5557}.
  21479. @item @code{log-file} (default: @code{"/var/log/cuirass-remote-server.log"})
  21480. Location of the log file.
  21481. @item @code{cache} (default: @code{"/var/cache/cuirass/remote"})
  21482. Use @var{cache} directory to cache build log files.
  21483. @item @code{trigger-url} (default: @code{#f})
  21484. Once a substitute is successfully fetched, trigger substitute baking at
  21485. @var{trigger-url}.
  21486. @item @code{public-key}
  21487. @item @code{private-key}
  21488. Use the specific @var{file}s as the public/private key pair used to sign
  21489. the store items being published.
  21490. @end table
  21491. @end deftp
  21492. At least one remote worker must also be started on any machine of the
  21493. local network to actually perform the builds and report their status.
  21494. @deftp {Data Type} cuirass-remote-worker-configuration
  21495. Data type representing the configuration of the Cuirass remote-worker.
  21496. @table @asis
  21497. @item @code{cuirass} (default: @code{cuirass})
  21498. The Cuirass package to use.
  21499. @item @code{workers} (default: @code{1})
  21500. Start @var{workers} parallel workers.
  21501. @item @code{server} (default: @code{#f})
  21502. Do not use Avahi discovery and connect to the given @code{server} IP
  21503. address instead.
  21504. @item @code{systems} (default: @code{(list (%current-system))})
  21505. Only request builds for the given @var{systems}.
  21506. @item @code{log-file} (default: @code{"/var/log/cuirass-remote-worker.log"})
  21507. Location of the log file.
  21508. @item @code{publish-port} (default: @code{5558})
  21509. The TCP port of the publish server. It defaults to @code{5558}.
  21510. @item @code{public-key}
  21511. @item @code{private-key}
  21512. Use the specific @var{file}s as the public/private key pair used to sign
  21513. the store items being published.
  21514. @end table
  21515. @end deftp
  21516. @node Power Management Services
  21517. @subsection Power Management Services
  21518. @cindex tlp
  21519. @cindex power management with TLP
  21520. @subsubheading TLP daemon
  21521. The @code{(gnu services pm)} module provides a Guix service definition
  21522. for the Linux power management tool TLP.
  21523. TLP enables various powersaving modes in userspace and kernel.
  21524. Contrary to @code{upower-service}, it is not a passive,
  21525. monitoring tool, as it will apply custom settings each time a new power
  21526. source is detected. More information can be found at
  21527. @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
  21528. @deffn {Scheme Variable} tlp-service-type
  21529. The service type for the TLP tool. The default settings are optimised
  21530. for battery life on most systems, but you can tweak them to your heart's
  21531. content by adding a valid @code{tlp-configuration}:
  21532. @lisp
  21533. (service tlp-service-type
  21534. (tlp-configuration
  21535. (cpu-scaling-governor-on-ac (list "performance"))
  21536. (sched-powersave-on-bat? #t)))
  21537. @end lisp
  21538. @end deffn
  21539. Each parameter definition is preceded by its type; for example,
  21540. @samp{boolean foo} indicates that the @code{foo} parameter
  21541. should be specified as a boolean. Types starting with
  21542. @code{maybe-} denote parameters that won't show up in TLP config file
  21543. when their value is @code{'disabled}.
  21544. @c The following documentation was initially generated by
  21545. @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
  21546. @c documentation is better, so we shouldn't hesitate to edit below as
  21547. @c needed. However if the change you want to make to this documentation
  21548. @c can be done in an automated way, it's probably easier to change
  21549. @c (generate-documentation) than to make it below and have to deal with
  21550. @c the churn as TLP updates.
  21551. Available @code{tlp-configuration} fields are:
  21552. @deftypevr {@code{tlp-configuration} parameter} package tlp
  21553. The TLP package.
  21554. @end deftypevr
  21555. @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
  21556. Set to true if you wish to enable TLP.
  21557. Defaults to @samp{#t}.
  21558. @end deftypevr
  21559. @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
  21560. Default mode when no power supply can be detected. Alternatives are AC
  21561. and BAT.
  21562. Defaults to @samp{"AC"}.
  21563. @end deftypevr
  21564. @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
  21565. Number of seconds Linux kernel has to wait after the disk goes idle,
  21566. before syncing on AC.
  21567. Defaults to @samp{0}.
  21568. @end deftypevr
  21569. @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
  21570. Same as @code{disk-idle-ac} but on BAT mode.
  21571. Defaults to @samp{2}.
  21572. @end deftypevr
  21573. @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
  21574. Dirty pages flushing periodicity, expressed in seconds.
  21575. Defaults to @samp{15}.
  21576. @end deftypevr
  21577. @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
  21578. Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
  21579. Defaults to @samp{60}.
  21580. @end deftypevr
  21581. @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
  21582. CPU frequency scaling governor on AC mode. With intel_pstate driver,
  21583. alternatives are powersave and performance. With acpi-cpufreq driver,
  21584. alternatives are ondemand, powersave, performance and conservative.
  21585. Defaults to @samp{disabled}.
  21586. @end deftypevr
  21587. @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
  21588. Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
  21589. Defaults to @samp{disabled}.
  21590. @end deftypevr
  21591. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
  21592. Set the min available frequency for the scaling governor on AC.
  21593. Defaults to @samp{disabled}.
  21594. @end deftypevr
  21595. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
  21596. Set the max available frequency for the scaling governor on AC.
  21597. Defaults to @samp{disabled}.
  21598. @end deftypevr
  21599. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
  21600. Set the min available frequency for the scaling governor on BAT.
  21601. Defaults to @samp{disabled}.
  21602. @end deftypevr
  21603. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
  21604. Set the max available frequency for the scaling governor on BAT.
  21605. Defaults to @samp{disabled}.
  21606. @end deftypevr
  21607. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
  21608. Limit the min P-state to control the power dissipation of the CPU, in AC
  21609. mode. Values are stated as a percentage of the available performance.
  21610. Defaults to @samp{disabled}.
  21611. @end deftypevr
  21612. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
  21613. Limit the max P-state to control the power dissipation of the CPU, in AC
  21614. mode. Values are stated as a percentage of the available performance.
  21615. Defaults to @samp{disabled}.
  21616. @end deftypevr
  21617. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
  21618. Same as @code{cpu-min-perf-on-ac} on BAT mode.
  21619. Defaults to @samp{disabled}.
  21620. @end deftypevr
  21621. @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
  21622. Same as @code{cpu-max-perf-on-ac} on BAT mode.
  21623. Defaults to @samp{disabled}.
  21624. @end deftypevr
  21625. @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
  21626. Enable CPU turbo boost feature on AC mode.
  21627. Defaults to @samp{disabled}.
  21628. @end deftypevr
  21629. @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
  21630. Same as @code{cpu-boost-on-ac?} on BAT mode.
  21631. Defaults to @samp{disabled}.
  21632. @end deftypevr
  21633. @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
  21634. Allow Linux kernel to minimize the number of CPU cores/hyper-threads
  21635. used under light load conditions.
  21636. Defaults to @samp{#f}.
  21637. @end deftypevr
  21638. @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
  21639. Same as @code{sched-powersave-on-ac?} but on BAT mode.
  21640. Defaults to @samp{#t}.
  21641. @end deftypevr
  21642. @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
  21643. Enable Linux kernel NMI watchdog.
  21644. Defaults to @samp{#f}.
  21645. @end deftypevr
  21646. @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
  21647. For Linux kernels with PHC patch applied, change CPU voltages. An
  21648. example value would be @samp{"F:V F:V F:V F:V"}.
  21649. Defaults to @samp{disabled}.
  21650. @end deftypevr
  21651. @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
  21652. Set CPU performance versus energy saving policy on AC@. Alternatives are
  21653. performance, normal, powersave.
  21654. Defaults to @samp{"performance"}.
  21655. @end deftypevr
  21656. @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
  21657. Same as @code{energy-perf-policy-ac} but on BAT mode.
  21658. Defaults to @samp{"powersave"}.
  21659. @end deftypevr
  21660. @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
  21661. Hard disk devices.
  21662. @end deftypevr
  21663. @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
  21664. Hard disk advanced power management level.
  21665. @end deftypevr
  21666. @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
  21667. Same as @code{disk-apm-bat} but on BAT mode.
  21668. @end deftypevr
  21669. @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
  21670. Hard disk spin down timeout. One value has to be specified for each
  21671. declared hard disk.
  21672. Defaults to @samp{disabled}.
  21673. @end deftypevr
  21674. @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
  21675. Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
  21676. Defaults to @samp{disabled}.
  21677. @end deftypevr
  21678. @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
  21679. Select IO scheduler for disk devices. One value has to be specified for
  21680. each declared hard disk. Example alternatives are cfq, deadline and
  21681. noop.
  21682. Defaults to @samp{disabled}.
  21683. @end deftypevr
  21684. @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
  21685. SATA aggressive link power management (ALPM) level. Alternatives are
  21686. min_power, medium_power, max_performance.
  21687. Defaults to @samp{"max_performance"}.
  21688. @end deftypevr
  21689. @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
  21690. Same as @code{sata-linkpwr-ac} but on BAT mode.
  21691. Defaults to @samp{"min_power"}.
  21692. @end deftypevr
  21693. @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
  21694. Exclude specified SATA host devices for link power management.
  21695. Defaults to @samp{disabled}.
  21696. @end deftypevr
  21697. @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
  21698. Enable Runtime Power Management for AHCI controller and disks on AC
  21699. mode.
  21700. Defaults to @samp{disabled}.
  21701. @end deftypevr
  21702. @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
  21703. Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
  21704. Defaults to @samp{disabled}.
  21705. @end deftypevr
  21706. @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
  21707. Seconds of inactivity before disk is suspended.
  21708. Defaults to @samp{15}.
  21709. @end deftypevr
  21710. @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
  21711. PCI Express Active State Power Management level. Alternatives are
  21712. default, performance, powersave.
  21713. Defaults to @samp{"performance"}.
  21714. @end deftypevr
  21715. @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
  21716. Same as @code{pcie-aspm-ac} but on BAT mode.
  21717. Defaults to @samp{"powersave"}.
  21718. @end deftypevr
  21719. @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
  21720. Radeon graphics clock speed level. Alternatives are low, mid, high,
  21721. auto, default.
  21722. Defaults to @samp{"high"}.
  21723. @end deftypevr
  21724. @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
  21725. Same as @code{radeon-power-ac} but on BAT mode.
  21726. Defaults to @samp{"low"}.
  21727. @end deftypevr
  21728. @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
  21729. Radeon dynamic power management method (DPM). Alternatives are battery,
  21730. performance.
  21731. Defaults to @samp{"performance"}.
  21732. @end deftypevr
  21733. @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
  21734. Same as @code{radeon-dpm-state-ac} but on BAT mode.
  21735. Defaults to @samp{"battery"}.
  21736. @end deftypevr
  21737. @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
  21738. Radeon DPM performance level. Alternatives are auto, low, high.
  21739. Defaults to @samp{"auto"}.
  21740. @end deftypevr
  21741. @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
  21742. Same as @code{radeon-dpm-perf-ac} but on BAT mode.
  21743. Defaults to @samp{"auto"}.
  21744. @end deftypevr
  21745. @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
  21746. Wifi power saving mode.
  21747. Defaults to @samp{#f}.
  21748. @end deftypevr
  21749. @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
  21750. Same as @code{wifi-power-ac?} but on BAT mode.
  21751. Defaults to @samp{#t}.
  21752. @end deftypevr
  21753. @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
  21754. Disable wake on LAN.
  21755. Defaults to @samp{#t}.
  21756. @end deftypevr
  21757. @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
  21758. Timeout duration in seconds before activating audio power saving on
  21759. Intel HDA and AC97 devices. A value of 0 disables power saving.
  21760. Defaults to @samp{0}.
  21761. @end deftypevr
  21762. @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
  21763. Same as @code{sound-powersave-ac} but on BAT mode.
  21764. Defaults to @samp{1}.
  21765. @end deftypevr
  21766. @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
  21767. Disable controller in powersaving mode on Intel HDA devices.
  21768. Defaults to @samp{#t}.
  21769. @end deftypevr
  21770. @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
  21771. Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
  21772. powered on again by releasing (and reinserting) the eject lever or by
  21773. pressing the disc eject button on newer models.
  21774. Defaults to @samp{#f}.
  21775. @end deftypevr
  21776. @deftypevr {@code{tlp-configuration} parameter} string bay-device
  21777. Name of the optical drive device to power off.
  21778. Defaults to @samp{"sr0"}.
  21779. @end deftypevr
  21780. @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
  21781. Runtime Power Management for PCI(e) bus devices. Alternatives are on
  21782. and auto.
  21783. Defaults to @samp{"on"}.
  21784. @end deftypevr
  21785. @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
  21786. Same as @code{runtime-pm-ac} but on BAT mode.
  21787. Defaults to @samp{"auto"}.
  21788. @end deftypevr
  21789. @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
  21790. Runtime Power Management for all PCI(e) bus devices, except blacklisted
  21791. ones.
  21792. Defaults to @samp{#t}.
  21793. @end deftypevr
  21794. @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
  21795. Exclude specified PCI(e) device addresses from Runtime Power Management.
  21796. Defaults to @samp{disabled}.
  21797. @end deftypevr
  21798. @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
  21799. Exclude PCI(e) devices assigned to the specified drivers from Runtime
  21800. Power Management.
  21801. @end deftypevr
  21802. @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
  21803. Enable USB autosuspend feature.
  21804. Defaults to @samp{#t}.
  21805. @end deftypevr
  21806. @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
  21807. Exclude specified devices from USB autosuspend.
  21808. Defaults to @samp{disabled}.
  21809. @end deftypevr
  21810. @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
  21811. Exclude WWAN devices from USB autosuspend.
  21812. Defaults to @samp{#t}.
  21813. @end deftypevr
  21814. @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
  21815. Include specified devices into USB autosuspend, even if they are already
  21816. excluded by the driver or via @code{usb-blacklist-wwan?}.
  21817. Defaults to @samp{disabled}.
  21818. @end deftypevr
  21819. @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
  21820. Enable USB autosuspend before shutdown.
  21821. Defaults to @samp{disabled}.
  21822. @end deftypevr
  21823. @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
  21824. Restore radio device state (bluetooth, wifi, wwan) from previous
  21825. shutdown on system startup.
  21826. Defaults to @samp{#f}.
  21827. @end deftypevr
  21828. @cindex thermald
  21829. @cindex CPU frequency scaling with thermald
  21830. @subsubheading Thermald daemon
  21831. The @code{(gnu services pm)} module provides an interface to
  21832. thermald, a CPU frequency scaling service which helps prevent overheating.
  21833. @defvr {Scheme Variable} thermald-service-type
  21834. This is the service type for
  21835. @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
  21836. Thermal Daemon, which is responsible for controlling the thermal state
  21837. of processors and preventing overheating.
  21838. @end defvr
  21839. @deftp {Data Type} thermald-configuration
  21840. Data type representing the configuration of @code{thermald-service-type}.
  21841. @table @asis
  21842. @item @code{ignore-cpuid-check?} (default: @code{#f})
  21843. Ignore cpuid check for supported CPU models.
  21844. @item @code{thermald} (default: @var{thermald})
  21845. Package object of thermald.
  21846. @end table
  21847. @end deftp
  21848. @node Audio Services
  21849. @subsection Audio Services
  21850. The @code{(gnu services audio)} module provides a service to start MPD
  21851. (the Music Player Daemon).
  21852. @cindex mpd
  21853. @subsubheading Music Player Daemon
  21854. The Music Player Daemon (MPD) is a service that can play music while
  21855. being controlled from the local machine or over the network by a variety
  21856. of clients.
  21857. The following example shows how one might run @code{mpd} as user
  21858. @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
  21859. @lisp
  21860. (service mpd-service-type
  21861. (mpd-configuration
  21862. (user "bob")
  21863. (port "6666")))
  21864. @end lisp
  21865. @defvr {Scheme Variable} mpd-service-type
  21866. The service type for @command{mpd}
  21867. @end defvr
  21868. @deftp {Data Type} mpd-configuration
  21869. Data type representing the configuration of @command{mpd}.
  21870. @table @asis
  21871. @item @code{user} (default: @code{"mpd"})
  21872. The user to run mpd as.
  21873. @item @code{music-dir} (default: @code{"~/Music"})
  21874. The directory to scan for music files.
  21875. @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
  21876. The directory to store playlists.
  21877. @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
  21878. The location of the music database.
  21879. @item @code{state-file} (default: @code{"~/.mpd/state"})
  21880. The location of the file that stores current MPD's state.
  21881. @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
  21882. The location of the sticker database.
  21883. @item @code{port} (default: @code{"6600"})
  21884. The port to run mpd on.
  21885. @item @code{address} (default: @code{"any"})
  21886. The address that mpd will bind to. To use a Unix domain socket,
  21887. an absolute path can be specified here.
  21888. @item @code{outputs} (default: @code{"(list (mpd-output))"})
  21889. The audio outputs that MPD can use. By default this is a single output using pulseaudio.
  21890. @end table
  21891. @end deftp
  21892. @deftp {Data Type} mpd-output
  21893. Data type representing an @command{mpd} audio output.
  21894. @table @asis
  21895. @item @code{name} (default: @code{"MPD"})
  21896. The name of the audio output.
  21897. @item @code{type} (default: @code{"pulse"})
  21898. The type of audio output.
  21899. @item @code{enabled?} (default: @code{#t})
  21900. Specifies whether this audio output is enabled when MPD is started. By
  21901. default, all audio outputs are enabled. This is just the default
  21902. setting when there is no state file; with a state file, the previous
  21903. state is restored.
  21904. @item @code{tags?} (default: @code{#t})
  21905. If set to @code{#f}, then MPD will not send tags to this output. This
  21906. is only useful for output plugins that can receive tags, for example the
  21907. @code{httpd} output plugin.
  21908. @item @code{always-on?} (default: @code{#f})
  21909. If set to @code{#t}, then MPD attempts to keep this audio output always
  21910. open. This may be useful for streaming servers, when you don’t want to
  21911. disconnect all listeners even when playback is accidentally stopped.
  21912. @item @code{mixer-type}
  21913. This field accepts a symbol that specifies which mixer should be used
  21914. for this audio output: the @code{hardware} mixer, the @code{software}
  21915. mixer, the @code{null} mixer (allows setting the volume, but with no
  21916. effect; this can be used as a trick to implement an external mixer
  21917. External Mixer) or no mixer (@code{none}).
  21918. @item @code{extra-options} (default: @code{'()})
  21919. An association list of option symbols to string values to be appended to
  21920. the audio output configuration.
  21921. @end table
  21922. @end deftp
  21923. The following example shows a configuration of @code{mpd} that provides
  21924. an HTTP audio streaming output.
  21925. @lisp
  21926. (service mpd-service-type
  21927. (mpd-configuration
  21928. (outputs
  21929. (list (mpd-output
  21930. (name "streaming")
  21931. (type "httpd")
  21932. (mixer-type 'null)
  21933. (extra-options
  21934. `((encoder . "vorbis")
  21935. (port . "8080"))))))))
  21936. @end lisp
  21937. @node Virtualization Services
  21938. @subsection Virtualization Services
  21939. The @code{(gnu services virtualization)} module provides services for
  21940. the libvirt and virtlog daemons, as well as other virtualization-related
  21941. services.
  21942. @subsubheading Libvirt daemon
  21943. @code{libvirtd} is the server side daemon component of the libvirt
  21944. virtualization management system. This daemon runs on host servers
  21945. and performs required management tasks for virtualized guests.
  21946. @deffn {Scheme Variable} libvirt-service-type
  21947. This is the type of the @uref{https://libvirt.org, libvirt daemon}.
  21948. Its value must be a @code{libvirt-configuration}.
  21949. @lisp
  21950. (service libvirt-service-type
  21951. (libvirt-configuration
  21952. (unix-sock-group "libvirt")
  21953. (tls-port "16555")))
  21954. @end lisp
  21955. @end deffn
  21956. @c Auto-generated with (generate-libvirt-documentation)
  21957. Available @code{libvirt-configuration} fields are:
  21958. @deftypevr {@code{libvirt-configuration} parameter} package libvirt
  21959. Libvirt package.
  21960. @end deftypevr
  21961. @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
  21962. Flag listening for secure TLS connections on the public TCP/IP port.
  21963. You must set @code{listen} for this to have any effect.
  21964. It is necessary to setup a CA and issue server certificates before using
  21965. this capability.
  21966. Defaults to @samp{#t}.
  21967. @end deftypevr
  21968. @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
  21969. Listen for unencrypted TCP connections on the public TCP/IP port. You must
  21970. set @code{listen} for this to have any effect.
  21971. Using the TCP socket requires SASL authentication by default. Only SASL
  21972. mechanisms which support data encryption are allowed. This is
  21973. DIGEST_MD5 and GSSAPI (Kerberos5).
  21974. Defaults to @samp{#f}.
  21975. @end deftypevr
  21976. @deftypevr {@code{libvirt-configuration} parameter} string tls-port
  21977. Port for accepting secure TLS connections. This can be a port number,
  21978. or service name.
  21979. Defaults to @samp{"16514"}.
  21980. @end deftypevr
  21981. @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
  21982. Port for accepting insecure TCP connections. This can be a port number,
  21983. or service name.
  21984. Defaults to @samp{"16509"}.
  21985. @end deftypevr
  21986. @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
  21987. IP address or hostname used for client connections.
  21988. Defaults to @samp{"0.0.0.0"}.
  21989. @end deftypevr
  21990. @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
  21991. Flag toggling mDNS advertisement of the libvirt service.
  21992. Alternatively can disable for all services on a host by stopping the
  21993. Avahi daemon.
  21994. Defaults to @samp{#f}.
  21995. @end deftypevr
  21996. @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
  21997. Default mDNS advertisement name. This must be unique on the immediate
  21998. broadcast network.
  21999. Defaults to @samp{"Virtualization Host <hostname>"}.
  22000. @end deftypevr
  22001. @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
  22002. UNIX domain socket group ownership. This can be used to allow a
  22003. 'trusted' set of users access to management capabilities without
  22004. becoming root.
  22005. Defaults to @samp{"root"}.
  22006. @end deftypevr
  22007. @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
  22008. UNIX socket permissions for the R/O socket. This is used for monitoring
  22009. VM status only.
  22010. Defaults to @samp{"0777"}.
  22011. @end deftypevr
  22012. @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
  22013. UNIX socket permissions for the R/W socket. Default allows only root.
  22014. If PolicyKit is enabled on the socket, the default will change to allow
  22015. everyone (eg, 0777)
  22016. Defaults to @samp{"0770"}.
  22017. @end deftypevr
  22018. @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
  22019. UNIX socket permissions for the admin socket. Default allows only owner
  22020. (root), do not change it unless you are sure to whom you are exposing
  22021. the access to.
  22022. Defaults to @samp{"0777"}.
  22023. @end deftypevr
  22024. @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
  22025. The directory in which sockets will be found/created.
  22026. Defaults to @samp{"/var/run/libvirt"}.
  22027. @end deftypevr
  22028. @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
  22029. Authentication scheme for UNIX read-only sockets. By default socket
  22030. permissions allow anyone to connect
  22031. Defaults to @samp{"polkit"}.
  22032. @end deftypevr
  22033. @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
  22034. Authentication scheme for UNIX read-write sockets. By default socket
  22035. permissions only allow root. If PolicyKit support was compiled into
  22036. libvirt, the default will be to use 'polkit' auth.
  22037. Defaults to @samp{"polkit"}.
  22038. @end deftypevr
  22039. @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
  22040. Authentication scheme for TCP sockets. If you don't enable SASL, then
  22041. all TCP traffic is cleartext. Don't do this outside of a dev/test
  22042. scenario.
  22043. Defaults to @samp{"sasl"}.
  22044. @end deftypevr
  22045. @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
  22046. Authentication scheme for TLS sockets. TLS sockets already have
  22047. encryption provided by the TLS layer, and limited authentication is done
  22048. by certificates.
  22049. It is possible to make use of any SASL authentication mechanism as well,
  22050. by using 'sasl' for this option
  22051. Defaults to @samp{"none"}.
  22052. @end deftypevr
  22053. @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
  22054. API access control scheme.
  22055. By default an authenticated user is allowed access to all APIs. Access
  22056. drivers can place restrictions on this.
  22057. Defaults to @samp{()}.
  22058. @end deftypevr
  22059. @deftypevr {@code{libvirt-configuration} parameter} string key-file
  22060. Server key file path. If set to an empty string, then no private key is
  22061. loaded.
  22062. Defaults to @samp{""}.
  22063. @end deftypevr
  22064. @deftypevr {@code{libvirt-configuration} parameter} string cert-file
  22065. Server key file path. If set to an empty string, then no certificate is
  22066. loaded.
  22067. Defaults to @samp{""}.
  22068. @end deftypevr
  22069. @deftypevr {@code{libvirt-configuration} parameter} string ca-file
  22070. Server key file path. If set to an empty string, then no CA certificate
  22071. is loaded.
  22072. Defaults to @samp{""}.
  22073. @end deftypevr
  22074. @deftypevr {@code{libvirt-configuration} parameter} string crl-file
  22075. Certificate revocation list path. If set to an empty string, then no
  22076. CRL is loaded.
  22077. Defaults to @samp{""}.
  22078. @end deftypevr
  22079. @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
  22080. Disable verification of our own server certificates.
  22081. When libvirtd starts it performs some sanity checks against its own
  22082. certificates.
  22083. Defaults to @samp{#f}.
  22084. @end deftypevr
  22085. @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
  22086. Disable verification of client certificates.
  22087. Client certificate verification is the primary authentication mechanism.
  22088. Any client which does not present a certificate signed by the CA will be
  22089. rejected.
  22090. Defaults to @samp{#f}.
  22091. @end deftypevr
  22092. @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
  22093. Whitelist of allowed x509 Distinguished Name.
  22094. Defaults to @samp{()}.
  22095. @end deftypevr
  22096. @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
  22097. Whitelist of allowed SASL usernames. The format for username depends on
  22098. the SASL authentication mechanism.
  22099. Defaults to @samp{()}.
  22100. @end deftypevr
  22101. @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
  22102. Override the compile time default TLS priority string. The default is
  22103. usually @samp{"NORMAL"} unless overridden at build time. Only set this is it
  22104. is desired for libvirt to deviate from the global default settings.
  22105. Defaults to @samp{"NORMAL"}.
  22106. @end deftypevr
  22107. @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
  22108. Maximum number of concurrent client connections to allow over all
  22109. sockets combined.
  22110. Defaults to @samp{5000}.
  22111. @end deftypevr
  22112. @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
  22113. Maximum length of queue of connections waiting to be accepted by the
  22114. daemon. Note, that some protocols supporting retransmission may obey
  22115. this so that a later reattempt at connection succeeds.
  22116. Defaults to @samp{1000}.
  22117. @end deftypevr
  22118. @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
  22119. Maximum length of queue of accepted but not yet authenticated clients.
  22120. Set this to zero to turn this feature off
  22121. Defaults to @samp{20}.
  22122. @end deftypevr
  22123. @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
  22124. Number of workers to start up initially.
  22125. Defaults to @samp{5}.
  22126. @end deftypevr
  22127. @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
  22128. Maximum number of worker threads.
  22129. If the number of active clients exceeds @code{min-workers}, then more
  22130. threads are spawned, up to max_workers limit. Typically you'd want
  22131. max_workers to equal maximum number of clients allowed.
  22132. Defaults to @samp{20}.
  22133. @end deftypevr
  22134. @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
  22135. Number of priority workers. If all workers from above pool are stuck,
  22136. some calls marked as high priority (notably domainDestroy) can be
  22137. executed in this pool.
  22138. Defaults to @samp{5}.
  22139. @end deftypevr
  22140. @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
  22141. Total global limit on concurrent RPC calls.
  22142. Defaults to @samp{20}.
  22143. @end deftypevr
  22144. @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
  22145. Limit on concurrent requests from a single client connection. To avoid
  22146. one client monopolizing the server this should be a small fraction of
  22147. the global max_requests and max_workers parameter.
  22148. Defaults to @samp{5}.
  22149. @end deftypevr
  22150. @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
  22151. Same as @code{min-workers} but for the admin interface.
  22152. Defaults to @samp{1}.
  22153. @end deftypevr
  22154. @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
  22155. Same as @code{max-workers} but for the admin interface.
  22156. Defaults to @samp{5}.
  22157. @end deftypevr
  22158. @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
  22159. Same as @code{max-clients} but for the admin interface.
  22160. Defaults to @samp{5}.
  22161. @end deftypevr
  22162. @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
  22163. Same as @code{max-queued-clients} but for the admin interface.
  22164. Defaults to @samp{5}.
  22165. @end deftypevr
  22166. @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
  22167. Same as @code{max-client-requests} but for the admin interface.
  22168. Defaults to @samp{5}.
  22169. @end deftypevr
  22170. @deftypevr {@code{libvirt-configuration} parameter} integer log-level
  22171. Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
  22172. Defaults to @samp{3}.
  22173. @end deftypevr
  22174. @deftypevr {@code{libvirt-configuration} parameter} string log-filters
  22175. Logging filters.
  22176. A filter allows to select a different logging level for a given category
  22177. of logs. The format for a filter is one of:
  22178. @itemize @bullet
  22179. @item
  22180. x:name
  22181. @item
  22182. x:+name
  22183. @end itemize
  22184. where @code{name} is a string which is matched against the category
  22185. given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
  22186. file, e.g., @samp{"remote"}, @samp{"qemu"}, or @samp{"util.json"} (the
  22187. name in the filter can be a substring of the full category name, in
  22188. order to match multiple similar categories), the optional @samp{"+"}
  22189. prefix tells libvirt to log stack trace for each message matching name,
  22190. and @code{x} is the minimal level where matching messages should be
  22191. logged:
  22192. @itemize @bullet
  22193. @item
  22194. 1: DEBUG
  22195. @item
  22196. 2: INFO
  22197. @item
  22198. 3: WARNING
  22199. @item
  22200. 4: ERROR
  22201. @end itemize
  22202. Multiple filters can be defined in a single filters statement, they just
  22203. need to be separated by spaces.
  22204. Defaults to @samp{"3:remote 4:event"}.
  22205. @end deftypevr
  22206. @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
  22207. Logging outputs.
  22208. An output is one of the places to save logging information. The format
  22209. for an output can be:
  22210. @table @code
  22211. @item x:stderr
  22212. output goes to stderr
  22213. @item x:syslog:name
  22214. use syslog for the output and use the given name as the ident
  22215. @item x:file:file_path
  22216. output to a file, with the given filepath
  22217. @item x:journald
  22218. output to journald logging system
  22219. @end table
  22220. In all case the x prefix is the minimal level, acting as a filter
  22221. @itemize @bullet
  22222. @item
  22223. 1: DEBUG
  22224. @item
  22225. 2: INFO
  22226. @item
  22227. 3: WARNING
  22228. @item
  22229. 4: ERROR
  22230. @end itemize
  22231. Multiple outputs can be defined, they just need to be separated by
  22232. spaces.
  22233. Defaults to @samp{"3:stderr"}.
  22234. @end deftypevr
  22235. @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
  22236. Allows usage of the auditing subsystem to be altered
  22237. @itemize @bullet
  22238. @item
  22239. 0: disable all auditing
  22240. @item
  22241. 1: enable auditing, only if enabled on host
  22242. @item
  22243. 2: enable auditing, and exit if disabled on host.
  22244. @end itemize
  22245. Defaults to @samp{1}.
  22246. @end deftypevr
  22247. @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
  22248. Send audit messages via libvirt logging infrastructure.
  22249. Defaults to @samp{#f}.
  22250. @end deftypevr
  22251. @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
  22252. Host UUID@. UUID must not have all digits be the same.
  22253. Defaults to @samp{""}.
  22254. @end deftypevr
  22255. @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
  22256. Source to read host UUID.
  22257. @itemize @bullet
  22258. @item
  22259. @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
  22260. @item
  22261. @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
  22262. @end itemize
  22263. If @code{dmidecode} does not provide a valid UUID a temporary UUID will
  22264. be generated.
  22265. Defaults to @samp{"smbios"}.
  22266. @end deftypevr
  22267. @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
  22268. A keepalive message is sent to a client after @code{keepalive_interval}
  22269. seconds of inactivity to check if the client is still responding. If
  22270. set to -1, libvirtd will never send keepalive requests; however clients
  22271. can still send them and the daemon will send responses.
  22272. Defaults to @samp{5}.
  22273. @end deftypevr
  22274. @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
  22275. Maximum number of keepalive messages that are allowed to be sent to the
  22276. client without getting any response before the connection is considered
  22277. broken.
  22278. In other words, the connection is automatically closed approximately
  22279. after @code{keepalive_interval * (keepalive_count + 1)} seconds since
  22280. the last message received from the client. When @code{keepalive-count}
  22281. is set to 0, connections will be automatically closed after
  22282. @code{keepalive-interval} seconds of inactivity without sending any
  22283. keepalive messages.
  22284. Defaults to @samp{5}.
  22285. @end deftypevr
  22286. @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
  22287. Same as above but for admin interface.
  22288. Defaults to @samp{5}.
  22289. @end deftypevr
  22290. @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
  22291. Same as above but for admin interface.
  22292. Defaults to @samp{5}.
  22293. @end deftypevr
  22294. @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
  22295. Timeout for Open vSwitch calls.
  22296. The @code{ovs-vsctl} utility is used for the configuration and its
  22297. timeout option is set by default to 5 seconds to avoid potential
  22298. infinite waits blocking libvirt.
  22299. Defaults to @samp{5}.
  22300. @end deftypevr
  22301. @c %end of autogenerated docs
  22302. @subsubheading Virtlog daemon
  22303. The virtlogd service is a server side daemon component of libvirt that is
  22304. used to manage logs from virtual machine consoles.
  22305. This daemon is not used directly by libvirt client applications, rather it
  22306. is called on their behalf by @code{libvirtd}. By maintaining the logs in a
  22307. standalone daemon, the main @code{libvirtd} daemon can be restarted without
  22308. risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
  22309. itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
  22310. @deffn {Scheme Variable} virtlog-service-type
  22311. This is the type of the virtlog daemon.
  22312. Its value must be a @code{virtlog-configuration}.
  22313. @lisp
  22314. (service virtlog-service-type
  22315. (virtlog-configuration
  22316. (max-clients 1000)))
  22317. @end lisp
  22318. @end deffn
  22319. @deftypevr {@code{virtlog-configuration} parameter} integer log-level
  22320. Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
  22321. Defaults to @samp{3}.
  22322. @end deftypevr
  22323. @deftypevr {@code{virtlog-configuration} parameter} string log-filters
  22324. Logging filters.
  22325. A filter allows to select a different logging level for a given category
  22326. of logs The format for a filter is one of:
  22327. @itemize @bullet
  22328. @item
  22329. x:name
  22330. @item
  22331. x:+name
  22332. @end itemize
  22333. where @code{name} is a string which is matched against the category
  22334. given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
  22335. file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
  22336. be a substring of the full category name, in order to match multiple
  22337. similar categories), the optional "+" prefix tells libvirt to log stack
  22338. trace for each message matching name, and @code{x} is the minimal level
  22339. where matching messages should be logged:
  22340. @itemize @bullet
  22341. @item
  22342. 1: DEBUG
  22343. @item
  22344. 2: INFO
  22345. @item
  22346. 3: WARNING
  22347. @item
  22348. 4: ERROR
  22349. @end itemize
  22350. Multiple filters can be defined in a single filters statement, they just
  22351. need to be separated by spaces.
  22352. Defaults to @samp{"3:remote 4:event"}.
  22353. @end deftypevr
  22354. @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
  22355. Logging outputs.
  22356. An output is one of the places to save logging information The format
  22357. for an output can be:
  22358. @table @code
  22359. @item x:stderr
  22360. output goes to stderr
  22361. @item x:syslog:name
  22362. use syslog for the output and use the given name as the ident
  22363. @item x:file:file_path
  22364. output to a file, with the given filepath
  22365. @item x:journald
  22366. output to journald logging system
  22367. @end table
  22368. In all case the x prefix is the minimal level, acting as a filter
  22369. @itemize @bullet
  22370. @item
  22371. 1: DEBUG
  22372. @item
  22373. 2: INFO
  22374. @item
  22375. 3: WARNING
  22376. @item
  22377. 4: ERROR
  22378. @end itemize
  22379. Multiple outputs can be defined, they just need to be separated by
  22380. spaces.
  22381. Defaults to @samp{"3:stderr"}.
  22382. @end deftypevr
  22383. @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
  22384. Maximum number of concurrent client connections to allow over all
  22385. sockets combined.
  22386. Defaults to @samp{1024}.
  22387. @end deftypevr
  22388. @deftypevr {@code{virtlog-configuration} parameter} integer max-size
  22389. Maximum file size before rolling over.
  22390. Defaults to @samp{2MB}
  22391. @end deftypevr
  22392. @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
  22393. Maximum number of backup files to keep.
  22394. Defaults to @samp{3}
  22395. @end deftypevr
  22396. @anchor{transparent-emulation-qemu}
  22397. @subsubheading Transparent Emulation with QEMU
  22398. @cindex emulation
  22399. @cindex @code{binfmt_misc}
  22400. @code{qemu-binfmt-service-type} provides support for transparent
  22401. emulation of program binaries built for different architectures---e.g.,
  22402. it allows you to transparently execute an ARMv7 program on an x86_64
  22403. machine. It achieves this by combining the @uref{https://www.qemu.org,
  22404. QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
  22405. This feature only allows you to emulate GNU/Linux on a different
  22406. architecture, but see below for GNU/Hurd support.
  22407. @defvr {Scheme Variable} qemu-binfmt-service-type
  22408. This is the type of the QEMU/binfmt service for transparent emulation.
  22409. Its value must be a @code{qemu-binfmt-configuration} object, which
  22410. specifies the QEMU package to use as well as the architecture we want to
  22411. emulated:
  22412. @lisp
  22413. (service qemu-binfmt-service-type
  22414. (qemu-binfmt-configuration
  22415. (platforms (lookup-qemu-platforms "arm" "aarch64"))))
  22416. @end lisp
  22417. In this example, we enable transparent emulation for the ARM and aarch64
  22418. platforms. Running @code{herd stop qemu-binfmt} turns it off, and
  22419. running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
  22420. herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
  22421. @end defvr
  22422. @deftp {Data Type} qemu-binfmt-configuration
  22423. This is the configuration for the @code{qemu-binfmt} service.
  22424. @table @asis
  22425. @item @code{platforms} (default: @code{'()})
  22426. The list of emulated QEMU platforms. Each item must be a @dfn{platform
  22427. object} as returned by @code{lookup-qemu-platforms} (see below).
  22428. For example, let's suppose you're on an x86_64 machine and you have this
  22429. service:
  22430. @lisp
  22431. (service qemu-binfmt-service-type
  22432. (qemu-binfmt-configuration
  22433. (platforms (lookup-qemu-platforms "arm"))
  22434. @end lisp
  22435. You can run:
  22436. @example
  22437. guix build -s armhf-linux inkscape
  22438. @end example
  22439. @noindent
  22440. and it will build Inkscape for ARMv7 @emph{as if it were a native
  22441. build}, transparently using QEMU to emulate the ARMv7 CPU@. Pretty handy
  22442. if you'd like to test a package build for an architecture you don't have
  22443. access to!
  22444. @item @code{qemu} (default: @code{qemu})
  22445. The QEMU package to use.
  22446. @end table
  22447. @end deftp
  22448. @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
  22449. Return the list of QEMU platform objects corresponding to
  22450. @var{platforms}@dots{}. @var{platforms} must be a list of strings
  22451. corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
  22452. @code{"mips64el"}, and so on.
  22453. @end deffn
  22454. @deffn {Scheme Procedure} qemu-platform? @var{obj}
  22455. Return true if @var{obj} is a platform object.
  22456. @end deffn
  22457. @deffn {Scheme Procedure} qemu-platform-name @var{platform}
  22458. Return the name of @var{platform}---a string such as @code{"arm"}.
  22459. @end deffn
  22460. @subsubheading The Hurd in a Virtual Machine
  22461. @cindex @code{hurd}
  22462. @cindex the Hurd
  22463. @cindex childhurd
  22464. Service @code{hurd-vm} provides support for running GNU/Hurd in a
  22465. virtual machine (VM), a so-called @dfn{childhurd}. This service is meant
  22466. to be used on GNU/Linux and the given GNU/Hurd operating system
  22467. configuration is cross-compiled. The virtual machine is a Shepherd
  22468. service that can be referred to by the names @code{hurd-vm} and
  22469. @code{childhurd} and be controlled with commands such as:
  22470. @example
  22471. herd start hurd-vm
  22472. herd stop childhurd
  22473. @end example
  22474. When the service is running, you can view its console by connecting to
  22475. it with a VNC client, for example with:
  22476. @example
  22477. guix environment --ad-hoc tigervnc-client -- \
  22478. vncviewer localhost:5900
  22479. @end example
  22480. The default configuration (see @code{hurd-vm-configuration} below)
  22481. spawns a secure shell (SSH) server in your GNU/Hurd system, which QEMU
  22482. (the virtual machine emulator) redirects to port 10222 on the host.
  22483. Thus, you can connect over SSH to the childhurd with:
  22484. @example
  22485. ssh root@@localhost -p 10022
  22486. @end example
  22487. The childhurd is volatile and stateless: it starts with a fresh root
  22488. file system every time you restart it. By default though, all the files
  22489. under @file{/etc/childhurd} on the host are copied as is to the root
  22490. file system of the childhurd when it boots. This allows you to
  22491. initialize ``secrets'' inside the VM: SSH host keys, authorized
  22492. substitute keys, and so on---see the explanation of @code{secret-root}
  22493. below.
  22494. @defvr {Scheme Variable} hurd-vm-service-type
  22495. This is the type of the Hurd in a Virtual Machine service. Its value
  22496. must be a @code{hurd-vm-configuration} object, which specifies the
  22497. operating system (@pxref{operating-system Reference}) and the disk size
  22498. for the Hurd Virtual Machine, the QEMU package to use as well as the
  22499. options for running it.
  22500. For example:
  22501. @lisp
  22502. (service hurd-vm-service-type
  22503. (hurd-vm-configuration
  22504. (disk-size (* 5000 (expt 2 20))) ;5G
  22505. (memory-size 1024))) ;1024MiB
  22506. @end lisp
  22507. would create a disk image big enough to build GNU@tie{}Hello, with some
  22508. extra memory.
  22509. @end defvr
  22510. @deftp {Data Type} hurd-vm-configuration
  22511. The data type representing the configuration for
  22512. @code{hurd-vm-service-type}.
  22513. @table @asis
  22514. @item @code{os} (default: @var{%hurd-vm-operating-system})
  22515. The operating system to instantiate. This default is bare-bones with a
  22516. permissive OpenSSH secure shell daemon listening on port 2222
  22517. (@pxref{Networking Services, @code{openssh-service-type}}).
  22518. @item @code{qemu} (default: @code{qemu-minimal})
  22519. The QEMU package to use.
  22520. @item @code{image} (default: @var{hurd-vm-disk-image})
  22521. The procedure used to build the disk-image built from this
  22522. configuration.
  22523. @item @code{disk-size} (default: @code{'guess})
  22524. The size of the disk image.
  22525. @item @code{memory-size} (default: @code{512})
  22526. The memory size of the Virtual Machine in mebibytes.
  22527. @item @code{options} (default: @code{'("--snapshot")})
  22528. The extra options for running QEMU.
  22529. @item @code{id} (default: @code{#f})
  22530. If set, a non-zero positive integer used to parameterize Childhurd
  22531. instances. It is appended to the service's name,
  22532. e.g. @code{childhurd1}.
  22533. @item @code{net-options} (default: @var{hurd-vm-net-options})
  22534. The procedure used to produce the list of QEMU networking options.
  22535. By default, it produces
  22536. @lisp
  22537. '("--device" "rtl8139,netdev=net0"
  22538. "--netdev" "user,id=net0\
  22539. ,hostfwd=tcp:127.0.0.1:@var{secrets-port}-:1004\
  22540. ,hostfwd=tcp:127.0.0.1:@var{ssh-port}-:2222\
  22541. ,hostfwd=tcp:127.0.0.1:@var{vnc-port}-:5900")
  22542. @end lisp
  22543. with forwarded ports:
  22544. @example
  22545. @var{secrets-port}: @code{(+ 11004 (* 1000 @var{ID}))}
  22546. @var{ssh-port}: @code{(+ 10022 (* 1000 @var{ID}))}
  22547. @var{vnc-port}: @code{(+ 15900 (* 1000 @var{ID}))}
  22548. @end example
  22549. @item @code{secret-root} (default: @file{/etc/childhurd})
  22550. The root directory with out-of-band secrets to be installed into the
  22551. childhurd once it runs. Childhurds are volatile which means that on
  22552. every startup, secrets such as the SSH host keys and Guix signing key
  22553. are recreated.
  22554. If the @file{/etc/childhurd} directory does not exist, the
  22555. @code{secret-service} running in the Childhurd will be sent an empty
  22556. list of secrets.
  22557. By default, the service automatically populates @file{/etc/childhurd}
  22558. with the following non-volatile secrets, unless they already exist:
  22559. @example
  22560. /etc/childhurd/etc/guix/acl
  22561. /etc/childhurd/etc/guix/signing-key.pub
  22562. /etc/childhurd/etc/guix/signing-key.sec
  22563. /etc/childhurd/etc/ssh/ssh_host_ed25519_key
  22564. /etc/childhurd/etc/ssh/ssh_host_ecdsa_key
  22565. /etc/childhurd/etc/ssh/ssh_host_ed25519_key.pub
  22566. /etc/childhurd/etc/ssh/ssh_host_ecdsa_key.pub
  22567. @end example
  22568. These files are automatically sent to the guest Hurd VM when it boots,
  22569. including permissions.
  22570. @cindex childhurd, offloading
  22571. @cindex Hurd, offloading
  22572. Having these files in place means that only a couple of things are
  22573. missing to allow the host to offload @code{i586-gnu} builds to the
  22574. childhurd:
  22575. @enumerate
  22576. @item
  22577. Authorizing the childhurd's key on the host so that the host accepts
  22578. build results coming from the childhurd, which can be done like so:
  22579. @example
  22580. guix archive --authorize < \
  22581. /etc/childhurd/etc/guix/signing-key.pub
  22582. @end example
  22583. @item
  22584. Adding the childhurd to @file{/etc/guix/machines.scm} (@pxref{Daemon
  22585. Offload Setup}).
  22586. @end enumerate
  22587. We're working towards making that happen automatically---get in touch
  22588. with us at @email{guix-devel@@gnu.org} to discuss it!
  22589. @end table
  22590. @end deftp
  22591. Note that by default the VM image is volatile, i.e., once stopped the
  22592. contents are lost. If you want a stateful image instead, override the
  22593. configuration's @code{image} and @code{options} without
  22594. the @code{--snapshot} flag using something along these lines:
  22595. @lisp
  22596. (service hurd-vm-service-type
  22597. (hurd-vm-configuration
  22598. (image (const "/out/of/store/writable/hurd.img"))
  22599. (options '())))
  22600. @end lisp
  22601. @subsubheading Ganeti
  22602. @cindex ganeti
  22603. @quotation Note
  22604. This service is considered experimental. Configuration options may be changed
  22605. in a backwards-incompatible manner, and not all features have been thorougly
  22606. tested. Users of this service are encouraged to share their experience at
  22607. @email{guix-devel@@gnu.org}.
  22608. @end quotation
  22609. Ganeti is a virtual machine management system. It is designed to keep virtual
  22610. machines running on a cluster of servers even in the event of hardware failures,
  22611. and to make maintenance and recovery tasks easy. It consists of multiple
  22612. services which are described later in this section. In addition to the Ganeti
  22613. service, you will need the OpenSSH service (@pxref{Networking Services,
  22614. @code{openssh-service-type}}), and update the @file{/etc/hosts} file
  22615. (@pxref{operating-system Reference, @code{hosts-file}}) with the cluster name
  22616. and address (or use a DNS server).
  22617. All nodes participating in a Ganeti cluster should have the same Ganeti and
  22618. @file{/etc/hosts} configuration. Here is an example configuration for a Ganeti
  22619. cluster node that supports multiple storage backends, and installs the
  22620. @code{debootstrap} and @code{guix} @dfn{OS providers}:
  22621. @lisp
  22622. (use-package-modules virtualization)
  22623. (use-service-modules base ganeti networking ssh)
  22624. (operating-system
  22625. ;; @dots{}
  22626. (host-name "node1")
  22627. (hosts-file (plain-file "hosts" (format #f "
  22628. 127.0.0.1 localhost
  22629. ::1 localhost
  22630. 192.168.1.200 ganeti.example.com
  22631. 192.168.1.201 node1.example.com node1
  22632. 192.168.1.202 node2.example.com node2
  22633. ")))
  22634. ;; Install QEMU so we can use KVM-based instances, and LVM, DRBD and Ceph
  22635. ;; in order to use the "plain", "drbd" and "rbd" storage backends.
  22636. (packages (append (map specification->package
  22637. '("qemu" "lvm2" "drbd-utils" "ceph"
  22638. ;; Add the debootstrap and guix OS providers.
  22639. "ganeti-instance-guix" "ganeti-instance-debootstrap"))
  22640. %base-packages))
  22641. (services
  22642. (append (list (static-networking-service "eth0" "192.168.1.201"
  22643. #:netmask "255.255.255.0"
  22644. #:gateway "192.168.1.254"
  22645. #:name-servers '("192.168.1.252"
  22646. "192.168.1.253"))
  22647. ;; Ganeti uses SSH to communicate between nodes.
  22648. (service openssh-service-type
  22649. (openssh-configuration
  22650. (permit-root-login 'without-password)))
  22651. (service ganeti-service-type
  22652. (ganeti-configuration
  22653. ;; This list specifies allowed file system paths
  22654. ;; for storing virtual machine images.
  22655. (file-storage-paths '("/srv/ganeti/file-storage"))
  22656. ;; This variable configures a single "variant" for
  22657. ;; both Debootstrap and Guix that works with KVM.
  22658. (os %default-ganeti-os))))
  22659. %base-services)))
  22660. @end lisp
  22661. Users are advised to read the
  22662. @url{http://docs.ganeti.org/ganeti/master/html/admin.html,Ganeti
  22663. administrators guide} to learn about the various cluster options and
  22664. day-to-day operations. There is also a
  22665. @url{https://guix.gnu.org/blog/2020/running-a-ganeti-cluster-on-guix/,blog post}
  22666. describing how to configure and initialize a small cluster.
  22667. @defvr {Scheme Variable} ganeti-service-type
  22668. This is a service type that includes all the various services that Ganeti
  22669. nodes should run.
  22670. Its value is a @code{ganeti-configuration} object that defines the package
  22671. to use for CLI operations, as well as configuration for the various daemons.
  22672. Allowed file storage paths and available guest operating systems are also
  22673. configured through this data type.
  22674. @end defvr
  22675. @deftp {Data Type} ganeti-configuration
  22676. The @code{ganeti} service takes the following configuration options:
  22677. @table @asis
  22678. @item @code{ganeti} (default: @code{ganeti})
  22679. The @code{ganeti} package to use. It will be installed to the system profile
  22680. and make @command{gnt-cluster}, @command{gnt-instance}, etc available. Note
  22681. that the value specified here does not affect the other services as each refer
  22682. to a specific @code{ganeti} package (see below).
  22683. @item @code{noded-configuration} (default: @code{(ganeti-noded-configuration)})
  22684. @itemx @code{confd-configuration} (default: @code{(ganeti-confd-configuration)})
  22685. @itemx @code{wconfd-configuration} (default: @code{(ganeti-wconfd-configuration)})
  22686. @itemx @code{luxid-configuration} (default: @code{(ganeti-luxid-configuration)})
  22687. @itemx @code{rapi-configuration} (default: @code{(ganeti-rapi-configuration)})
  22688. @itemx @code{kvmd-configuration} (default: @code{(ganeti-kvmd-configuration)})
  22689. @itemx @code{mond-configuration} (default: @code{(ganeti-mond-configuration)})
  22690. @itemx @code{metad-configuration} (default: @code{(ganeti-metad-configuration)})
  22691. @itemx @code{watcher-configuration} (default: @code{(ganeti-watcher-configuration)})
  22692. @itemx @code{cleaner-configuration} (default: @code{(ganeti-cleaner-configuration)})
  22693. These options control the various daemons and cron jobs that are distributed
  22694. with Ganeti. The possible values for these are described in detail below.
  22695. To override a setting, you must use the configuration type for that service:
  22696. @lisp
  22697. (service ganeti-service-type
  22698. (ganeti-configuration
  22699. (rapi-configuration
  22700. (ganeti-rapi-configuration
  22701. (interface "eth1"))))
  22702. (watcher-configuration
  22703. (ganeti-watcher-configuration
  22704. (rapi-ip "10.0.0.1"))))
  22705. @end lisp
  22706. @item @code{file-storage-paths} (default: @code{'()})
  22707. List of allowed directories for file storage backend.
  22708. @item @code{os} (default: @code{%default-ganeti-os})
  22709. List of @code{<ganeti-os>} records.
  22710. @end table
  22711. In essence @code{ganeti-service-type} is shorthand for declaring each service
  22712. individually:
  22713. @lisp
  22714. (service ganeti-noded-service-type)
  22715. (service ganeti-confd-service-type)
  22716. (service ganeti-wconfd-service-type)
  22717. (service ganeti-luxid-service-type)
  22718. (service ganeti-kvmd-service-type)
  22719. (service ganeti-mond-service-type)
  22720. (service ganeti-metad-service-type)
  22721. (service ganeti-watcher-service-type)
  22722. (service ganeti-cleaner-service-type)
  22723. @end lisp
  22724. Plus a service extension for @code{etc-service-type} that configures the file
  22725. storage backend and OS variants.
  22726. @end deftp
  22727. @deftp {Data Type} ganeti-os
  22728. This data type is suitable for passing to the @code{os} parameter of
  22729. @code{ganeti-configuration}. It takes the following parameters:
  22730. @table @asis
  22731. @item @code{name}
  22732. The name for this OS provider. It is only used to specify where the
  22733. configuration ends up. Setting it to ``debootstrap'' will create
  22734. @file{/etc/ganeti/instance-debootstrap}.
  22735. @item @code{extension}
  22736. The file extension for variants of this OS type. For example
  22737. @file{.conf} or @file{.scm}.
  22738. @item @code{variants} (default: @code{'()})
  22739. List of @code{ganeti-os-variant} objects for this OS.
  22740. @end table
  22741. @end deftp
  22742. @deftp {Data Type} ganeti-os-variant
  22743. This is the data type for a Ganeti OS variant. It takes the following
  22744. parameters:
  22745. @table @asis
  22746. @item @code{name}
  22747. The name of this variant.
  22748. @item @code{configuration}
  22749. A configuration file for this variant.
  22750. @end table
  22751. @end deftp
  22752. @defvr {Scheme Variable} %default-debootstrap-hooks
  22753. This variable contains hooks to configure networking and the GRUB bootloader.
  22754. @end defvr
  22755. @defvr {Scheme Variable} %default-debootstrap-extra-pkgs
  22756. This variable contains a list of packages suitable for a fully-virtualized guest.
  22757. @end defvr
  22758. @deftp {Data Type} debootstrap-configuration
  22759. This data type creates configuration files suitable for the debootstrap OS provider.
  22760. @table @asis
  22761. @item @code{hooks} (default: @code{%default-debootstrap-hooks})
  22762. When not @code{#f}, this must be a G-expression that specifies a directory with
  22763. scripts that will run when the OS is installed. It can also be a list of
  22764. @code{(name . file-like)} pairs. For example:
  22765. @lisp
  22766. `((99-hello-world . ,(plain-file "#!/bin/sh\necho Hello, World")))
  22767. @end lisp
  22768. That will create a directory with one executable named @code{99-hello-world}
  22769. and run it every time this variant is installed. If set to @code{#f}, hooks
  22770. in @file{/etc/ganeti/instance-debootstrap/hooks} will be used, if any.
  22771. @item @code{proxy} (default: @code{#f})
  22772. Optional HTTP proxy to use.
  22773. @item @code{mirror} (default: @code{#f})
  22774. The Debian mirror. Typically something like @code{http://ftp.no.debian.org/debian}.
  22775. The default varies depending on the distribution.
  22776. @item @code{arch} (default: @code{#f})
  22777. The dpkg architecture. Set to @code{armhf} to debootstrap an ARMv7 instance
  22778. on an AArch64 host. Default is to use the current system architecture.
  22779. @item @code{suite} (default: @code{"stable"})
  22780. When set, this must be a Debian distribution ``suite'' such as @code{buster}
  22781. or @code{focal}. If set to @code{#f}, the default for the OS provider is used.
  22782. @item @code{extra-pkgs} (default: @code{%default-debootstrap-extra-pkgs})
  22783. List of extra packages that will get installed by dpkg in addition
  22784. to the minimal system.
  22785. @item @code{components} (default: @code{#f})
  22786. When set, must be a list of Debian repository ``components''. For example
  22787. @code{'("main" "contrib")}.
  22788. @item @code{generate-cache?} (default: @code{#t})
  22789. Whether to automatically cache the generated debootstrap archive.
  22790. @item @code{clean-cache} (default: @code{14})
  22791. Discard the cache after this amount of days. Use @code{#f} to never
  22792. clear the cache.
  22793. @item @code{partition-style} (default: @code{'msdos})
  22794. The type of partition to create. When set, it must be one of
  22795. @code{'msdos}, @code{'none} or a string.
  22796. @item @code{partition-alignment} (default: @code{2048})
  22797. Alignment of the partition in sectors.
  22798. @end table
  22799. @end deftp
  22800. @deffn {Scheme Procedure} debootstrap-variant @var{name} @var{configuration}
  22801. This is a helper procedure that creates a @code{ganeti-os-variant} record. It
  22802. takes two parameters: a name and a @code{debootstrap-configuration} object.
  22803. @end deffn
  22804. @deffn {Scheme Procedure} debootstrap-os @var{variants}@dots{}
  22805. This is a helper procedure that creates a @code{ganeti-os} record. It takes
  22806. a list of variants created with @code{debootstrap-variant}.
  22807. @end deffn
  22808. @deffn {Scheme Procedure} guix-variant @var{name} @var{configuration}
  22809. This is a helper procedure that creates a @code{ganeti-os-variant} record for
  22810. use with the Guix OS provider. It takes a name and a G-expression that returns
  22811. a ``file-like'' (@pxref{G-Expressions, file-like objects}) object containing a
  22812. Guix System configuration.
  22813. @end deffn
  22814. @deffn {Scheme Procedure} guix-os @var{variants}@dots{}
  22815. This is a helper procedure that creates a @code{ganeti-os} record. It
  22816. takes a list of variants produced by @code{guix-variant}.
  22817. @end deffn
  22818. @defvr {Scheme Variable} %default-debootstrap-variants
  22819. This is a convenience variable to make the debootstrap provider work
  22820. ``out of the box'' without users having to declare variants manually. It
  22821. contains a single debootstrap variant with the default configuration:
  22822. @lisp
  22823. (list (debootstrap-variant
  22824. "default"
  22825. (debootstrap-configuration)))
  22826. @end lisp
  22827. @end defvr
  22828. @defvr {Scheme Variable} %default-guix-variants
  22829. This is a convenience variable to make the Guix OS provider work without
  22830. additional configuration. It creates a virtual machine that has an SSH
  22831. server, a serial console, and authorizes the Ganeti hosts SSH keys.
  22832. @lisp
  22833. (list (guix-variant
  22834. "default"
  22835. (file-append ganeti-instance-guix
  22836. "/share/doc/ganeti-instance-guix/examples/dynamic.scm")))
  22837. @end lisp
  22838. @end defvr
  22839. Users can implement support for OS providers unbeknownst to Guix by extending
  22840. the @code{ganeti-os} and @code{ganeti-os-variant} records appropriately.
  22841. For example:
  22842. @lisp
  22843. (ganeti-os
  22844. (name "custom")
  22845. (extension ".conf")
  22846. (variants
  22847. (list (ganeti-os-variant
  22848. (name "foo")
  22849. (configuration (plain-file "bar" "this is fine"))))))
  22850. @end lisp
  22851. That creates @file{/etc/ganeti/instance-custom/variants/foo.conf} which points
  22852. to a file in the store with contents @code{this is fine}. It also creates
  22853. @file{/etc/ganeti/instance-custom/variants/variants.list} with contents @code{foo}.
  22854. Obviously this may not work for all OS providers out there. If you find the
  22855. interface limiting, please reach out to @email{guix-devel@@gnu.org}.
  22856. The rest of this section documents the various services that are included by
  22857. @code{ganeti-service-type}.
  22858. @defvr {Scheme Variable} ganeti-noded-service-type
  22859. @command{ganeti-noded} is the daemon responsible for node-specific functions
  22860. within the Ganeti system. The value of this service must be a
  22861. @code{ganeti-noded-configuration} object.
  22862. @end defvr
  22863. @deftp {Data Type} ganeti-noded-configuration
  22864. This is the configuration for the @code{ganeti-noded} service.
  22865. @table @asis
  22866. @item @code{ganeti} (default: @code{ganeti})
  22867. The @code{ganeti} package to use for this service.
  22868. @item @code{port} (default: @code{1811})
  22869. The TCP port on which the node daemon listens for network requests.
  22870. @item @code{address} (default: @code{"0.0.0.0"})
  22871. The network address that the daemon will bind to. The default address means
  22872. bind to all available addresses.
  22873. @item @code{interface} (default: @code{#f})
  22874. When this is set, it must be a specific network interface (e.g.@: @code{eth0})
  22875. that the daemon will bind to.
  22876. @item @code{max-clients} (default: @code{20})
  22877. This sets a limit on the maximum number of simultaneous client connections
  22878. that the daemon will handle. Connections above this count are accepted, but
  22879. no responses will be sent until enough connections have closed.
  22880. @item @code{ssl?} (default: @code{#t})
  22881. Whether to use SSL/TLS to encrypt network communications. The certificate
  22882. is automatically provisioned by the cluster and can be rotated with
  22883. @command{gnt-cluster renew-crypto}.
  22884. @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
  22885. This can be used to provide a specific encryption key for TLS communications.
  22886. @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
  22887. This can be used to provide a specific certificate for TLS communications.
  22888. @item @code{debug?} (default: @code{#f})
  22889. When true, the daemon performs additional logging for debugging purposes.
  22890. Note that this will leak encryption details to the log files, use with caution.
  22891. @end table
  22892. @end deftp
  22893. @defvr {Scheme Variable} ganeti-confd-service-type
  22894. @command{ganeti-confd} answers queries related to the configuration of a
  22895. Ganeti cluster. The purpose of this daemon is to have a highly available
  22896. and fast way to query cluster configuration values. It is automatically
  22897. active on all @dfn{master candidates}. The value of this service must be a
  22898. @code{ganeti-confd-configuration} object.
  22899. @end defvr
  22900. @deftp {Data Type} ganeti-confd-configuration
  22901. This is the configuration for the @code{ganeti-confd} service.
  22902. @table @asis
  22903. @item @code{ganeti} (default: @code{ganeti})
  22904. The @code{ganeti} package to use for this service.
  22905. @item @code{port} (default: @code{1814})
  22906. The UDP port on which to listen for network requests.
  22907. @item @code{address} (default: @code{"0.0.0.0"})
  22908. Network address that the daemon will bind to.
  22909. @item @code{debug?} (default: @code{#f})
  22910. When true, the daemon performs additional logging for debugging purposes.
  22911. @end table
  22912. @end deftp
  22913. @defvr {Scheme Variable} ganeti-wconfd-service-type
  22914. @command{ganeti-wconfd} is the daemon that has authoritative knowledge
  22915. about the cluster configuration and is the only entity that can accept
  22916. changes to it. All jobs that need to modify the configuration will do so
  22917. by sending appropriate requests to this daemon. It only runs on the
  22918. @dfn{master node} and will automatically disable itself on other nodes.
  22919. The value of this service must be a
  22920. @code{ganeti-wconfd-configuration} object.
  22921. @end defvr
  22922. @deftp {Data Type} ganeti-wconfd-configuration
  22923. This is the configuration for the @code{ganeti-wconfd} service.
  22924. @table @asis
  22925. @item @code{ganeti} (default: @code{ganeti})
  22926. The @code{ganeti} package to use for this service.
  22927. @item @code{no-voting?} (default: @code{#f})
  22928. The daemon will refuse to start if the majority of cluster nodes does not
  22929. agree that it is running on the master node. Set to @code{#t} to start
  22930. even if a quorum can not be reached (dangerous, use with caution).
  22931. @item @code{debug?} (default: @code{#f})
  22932. When true, the daemon performs additional logging for debugging purposes.
  22933. @end table
  22934. @end deftp
  22935. @defvr {Scheme Variable} ganeti-luxid-service-type
  22936. @command{ganeti-luxid} is a daemon used to answer queries related to the
  22937. configuration and the current live state of a Ganeti cluster. Additionally,
  22938. it is the authoritative daemon for the Ganeti job queue. Jobs can be
  22939. submitted via this daemon and it schedules and starts them.
  22940. It takes a @code{ganeti-luxid-configuration} object.
  22941. @end defvr
  22942. @deftp {Data Type} ganeti-luxid-configuration
  22943. This is the configuration for the @code{ganeti-wconfd} service.
  22944. @table @asis
  22945. @item @code{ganeti} (default: @code{ganeti})
  22946. The @code{ganeti} package to use for this service.
  22947. @item @code{no-voting?} (default: @code{#f})
  22948. The daemon will refuse to start if it cannot verify that the majority of
  22949. cluster nodes believes that it is running on the master node. Set to
  22950. @code{#t} to ignore such checks and start anyway (this can be dangerous).
  22951. @item @code{debug?} (default: @code{#f})
  22952. When true, the daemon performs additional logging for debugging purposes.
  22953. @end table
  22954. @end deftp
  22955. @defvr {Scheme Variable} ganeti-rapi-service-type
  22956. @command{ganeti-rapi} provides a remote API for Ganeti clusters. It runs on
  22957. the master node and can be used to perform cluster actions programmatically
  22958. via a JSON-based RPC protocol.
  22959. Most query operations are allowed without authentication (unless
  22960. @var{require-authentication?} is set), whereas write operations require
  22961. explicit authorization via the @file{/var/lib/ganeti/rapi/users} file. See
  22962. the @url{http://docs.ganeti.org/ganeti/master/html/rapi.html, Ganeti Remote
  22963. API documentation} for more information.
  22964. The value of this service must be a @code{ganeti-rapi-configuration} object.
  22965. @end defvr
  22966. @deftp {Data Type} ganeti-rapi-configuration
  22967. This is the configuration for the @code{ganeti-rapi} service.
  22968. @table @asis
  22969. @item @code{ganeti} (default: @code{ganeti})
  22970. The @code{ganeti} package to use for this service.
  22971. @item @code{require-authentication?} (default: @code{#f})
  22972. Whether to require authentication even for read-only operations.
  22973. @item @code{port} (default: @code{5080})
  22974. The TCP port on which to listen to API requests.
  22975. @item @code{address} (default: @code{"0.0.0.0"})
  22976. The network address that the service will bind to. By default it listens
  22977. on all configured addresses.
  22978. @item @code{interface} (default: @code{#f})
  22979. When set, it must specify a specific network interface such as @code{eth0}
  22980. that the daemon will bind to.
  22981. @item @code{max-clients} (default: @code{20})
  22982. The maximum number of simultaneous client requests to handle. Further
  22983. connections are allowed, but no responses are sent until enough connections
  22984. have closed.
  22985. @item @code{ssl?} (default: @code{#t})
  22986. Whether to use SSL/TLS encryption on the RAPI port.
  22987. @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
  22988. This can be used to provide a specific encryption key for TLS communications.
  22989. @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
  22990. This can be used to provide a specific certificate for TLS communications.
  22991. @item @code{debug?} (default: @code{#f})
  22992. When true, the daemon performs additional logging for debugging purposes.
  22993. Note that this will leak encryption details to the log files, use with caution.
  22994. @end table
  22995. @end deftp
  22996. @defvr {Scheme Variable} ganeti-kvmd-service-type
  22997. @command{ganeti-kvmd} is responsible for determining whether a given KVM
  22998. instance was shut down by an administrator or a user. Normally Ganeti will
  22999. restart an instance that was not stopped through Ganeti itself. If the
  23000. cluster option @code{user_shutdown} is true, this daemon monitors the
  23001. @code{QMP} socket provided by QEMU and listens for shutdown events, and
  23002. marks the instance as @dfn{USER_down} instead of @dfn{ERROR_down} when
  23003. it shuts down gracefully by itself.
  23004. It takes a @code{ganeti-kvmd-configuration} object.
  23005. @end defvr
  23006. @deftp {Data Type} ganeti-kvmd-configuration
  23007. @table @asis
  23008. @item @code{ganeti} (default: @code{ganeti})
  23009. The @code{ganeti} package to use for this service.
  23010. @item @code{debug?} (default: @code{#f})
  23011. When true, the daemon performs additional logging for debugging purposes.
  23012. @end table
  23013. @end deftp
  23014. @defvr {Scheme Variable} ganeti-mond-service-type
  23015. @command{ganeti-mond} is an optional daemon that provides Ganeti monitoring
  23016. functionality. It is responsible for running data collectors and publish the
  23017. collected information through a HTTP interface.
  23018. It takes a @code{ganeti-mond-configuration} object.
  23019. @end defvr
  23020. @deftp {Data Type} ganeti-mond-configuration
  23021. @table @asis
  23022. @item @code{ganeti} (default: @code{ganeti})
  23023. The @code{ganeti} package to use for this service.
  23024. @item @code{port} (default: @code{1815})
  23025. The port on which the daemon will listen.
  23026. @item @code{address} (default: @code{"0.0.0.0"})
  23027. The network address that the daemon will bind to. By default it binds to all
  23028. available interfaces.
  23029. @item @code{debug?} (default: @code{#f})
  23030. When true, the daemon performs additional logging for debugging purposes.
  23031. @end table
  23032. @end deftp
  23033. @defvr {Scheme Variable} ganeti-metad-service-type
  23034. @command{ganeti-metad} is an optional daemon that can be used to provide
  23035. information about the cluster to instances or OS install scripts.
  23036. It takes a @code{ganeti-metad-configuration} object.
  23037. @end defvr
  23038. @deftp {Data Type} ganeti-metad-configuration
  23039. @table @asis
  23040. @item @code{ganeti} (default: @code{ganeti})
  23041. The @code{ganeti} package to use for this service.
  23042. @item @code{port} (default: @code{80})
  23043. The port on which the daemon will listen.
  23044. @item @code{address} (default: @code{#f})
  23045. If set, the daemon will bind to this address only. If left unset, the behavior
  23046. depends on the cluster configuration.
  23047. @item @code{debug?} (default: @code{#f})
  23048. When true, the daemon performs additional logging for debugging purposes.
  23049. @end table
  23050. @end deftp
  23051. @defvr {Scheme Variable} ganeti-watcher-service-type
  23052. @command{ganeti-watcher} is a script designed to run periodically and ensure
  23053. the health of a cluster. It will automatically restart instances that have
  23054. stopped without Ganeti's consent, and repairs DRBD links in case a node has
  23055. rebooted. It also archives old cluster jobs and restarts Ganeti daemons
  23056. that are not running. If the cluster parameter @code{ensure_node_health}
  23057. is set, the watcher will also shutdown instances and DRBD devices if the
  23058. node it is running on is declared offline by known master candidates.
  23059. It can be paused on all nodes with @command{gnt-cluster watcher pause}.
  23060. The service takes a @code{ganeti-watcher-configuration} object.
  23061. @end defvr
  23062. @deftp {Data Type} ganeti-watcher-configuration
  23063. @table @asis
  23064. @item @code{ganeti} (default: @code{ganeti})
  23065. The @code{ganeti} package to use for this service.
  23066. @item @code{schedule} (default: @code{'(next-second-from (next-minute (range 0 60 5)))})
  23067. How often to run the script. The default is every five minutes.
  23068. @item @code{rapi-ip} (default: @code{#f})
  23069. This option needs to be specified only if the RAPI daemon is configured to use
  23070. a particular interface or address. By default the cluster address is used.
  23071. @item @code{job-age} (default: @code{(* 6 3600)})
  23072. Archive cluster jobs older than this age, specified in seconds. The default
  23073. is 6 hours. This keeps @command{gnt-job list} manageable.
  23074. @item @code{verify-disks?} (default: @code{#t})
  23075. If this is @code{#f}, the watcher will not try to repair broken DRBD links
  23076. automatically. Administrators will need to use @command{gnt-cluster verify-disks}
  23077. manually instead.
  23078. @item @code{debug?} (default: @code{#f})
  23079. When @code{#t}, the script performs additional logging for debugging purposes.
  23080. @end table
  23081. @end deftp
  23082. @defvr {Scheme Variable} ganeti-cleaner-service-type
  23083. @command{ganeti-cleaner} is a script designed to run periodically and remove
  23084. old files from the cluster. This service type controls two @dfn{cron jobs}:
  23085. one intended for the master node that permanently purges old cluster jobs,
  23086. and one intended for every node that removes expired X509 certificates, keys,
  23087. and outdated @command{ganeti-watcher} information. Like all Ganeti services,
  23088. it is safe to include even on non-master nodes as it will disable itself as
  23089. necessary.
  23090. It takes a @code{ganeti-cleaner-configuration} object.
  23091. @end defvr
  23092. @deftp {Data Type} ganeti-cleaner-configuration
  23093. @table @asis
  23094. @item @code{ganeti} (default: @code{ganeti})
  23095. The @code{ganeti} package to use for the @command{gnt-cleaner} command.
  23096. @item @code{master-schedule} (default: @code{"45 1 * * *"})
  23097. How often to run the master cleaning job. The default is once per day, at
  23098. 01:45:00.
  23099. @item @code{node-schedule} (default: @code{"45 2 * * *"})
  23100. How often to run the node cleaning job. The default is once per day, at
  23101. 02:45:00.
  23102. @end table
  23103. @end deftp
  23104. @node Version Control Services
  23105. @subsection Version Control Services
  23106. The @code{(gnu services version-control)} module provides a service to
  23107. allow remote access to local Git repositories. There are three options:
  23108. the @code{git-daemon-service}, which provides access to repositories via
  23109. the @code{git://} unsecured TCP-based protocol, extending the
  23110. @code{nginx} web server to proxy some requests to
  23111. @code{git-http-backend}, or providing a web interface with
  23112. @code{cgit-service-type}.
  23113. @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
  23114. Return a service that runs @command{git daemon}, a simple TCP server to
  23115. expose repositories over the Git protocol for anonymous access.
  23116. The optional @var{config} argument should be a
  23117. @code{<git-daemon-configuration>} object, by default it allows read-only
  23118. access to exported@footnote{By creating the magic file
  23119. @file{git-daemon-export-ok} in the repository directory.} repositories under
  23120. @file{/srv/git}.
  23121. @end deffn
  23122. @deftp {Data Type} git-daemon-configuration
  23123. Data type representing the configuration for @code{git-daemon-service}.
  23124. @table @asis
  23125. @item @code{package} (default: @code{git})
  23126. Package object of the Git distributed version control system.
  23127. @item @code{export-all?} (default: @code{#f})
  23128. Whether to allow access for all Git repositories, even if they do not
  23129. have the @file{git-daemon-export-ok} file.
  23130. @item @code{base-path} (default: @file{/srv/git})
  23131. Whether to remap all the path requests as relative to the given path.
  23132. If you run @command{git daemon} with @code{(base-path "/srv/git")} on
  23133. @samp{example.com}, then if you later try to pull
  23134. @indicateurl{git://example.com/hello.git}, git daemon will interpret the
  23135. path as @file{/srv/git/hello.git}.
  23136. @item @code{user-path} (default: @code{#f})
  23137. Whether to allow @code{~user} notation to be used in requests. When
  23138. specified with empty string, requests to
  23139. @indicateurl{git://host/~alice/foo} is taken as a request to access
  23140. @code{foo} repository in the home directory of user @code{alice}. If
  23141. @code{(user-path "@var{path}")} is specified, the same request is taken
  23142. as a request to access @file{@var{path}/foo} repository in the home
  23143. directory of user @code{alice}.
  23144. @item @code{listen} (default: @code{'()})
  23145. Whether to listen on specific IP addresses or hostnames, defaults to
  23146. all.
  23147. @item @code{port} (default: @code{#f})
  23148. Whether to listen on an alternative port, which defaults to 9418.
  23149. @item @code{whitelist} (default: @code{'()})
  23150. If not empty, only allow access to this list of directories.
  23151. @item @code{extra-options} (default: @code{'()})
  23152. Extra options will be passed to @command{git daemon}, please run
  23153. @command{man git-daemon} for more information.
  23154. @end table
  23155. @end deftp
  23156. The @code{git://} protocol lacks authentication. When you pull from a
  23157. repository fetched via @code{git://}, you don't know whether the data you
  23158. receive was modified or is even coming from the specified host, and your
  23159. connection is subject to eavesdropping. It's better to use an authenticated
  23160. and encrypted transport, such as @code{https}. Although Git allows you
  23161. to serve repositories using unsophisticated file-based web servers,
  23162. there is a faster protocol implemented by the @code{git-http-backend}
  23163. program. This program is the back-end of a proper Git web service. It
  23164. is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
  23165. on running the necessary @code{fcgiwrap} daemon.
  23166. Guix has a separate configuration data type for serving Git repositories
  23167. over HTTP.
  23168. @deftp {Data Type} git-http-configuration
  23169. Data type representing the configuration for a future
  23170. @code{git-http-service-type}; can currently be used to configure Nginx
  23171. through @code{git-http-nginx-location-configuration}.
  23172. @table @asis
  23173. @item @code{package} (default: @var{git})
  23174. Package object of the Git distributed version control system.
  23175. @item @code{git-root} (default: @file{/srv/git})
  23176. Directory containing the Git repositories to expose to the world.
  23177. @item @code{export-all?} (default: @code{#f})
  23178. Whether to expose access for all Git repositories in @var{git-root},
  23179. even if they do not have the @file{git-daemon-export-ok} file.
  23180. @item @code{uri-path} (default: @samp{/git/})
  23181. Path prefix for Git access. With the default @samp{/git/} prefix, this
  23182. will map @indicateurl{http://@var{server}/git/@var{repo}.git} to
  23183. @file{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
  23184. with this prefix are not passed on to this Git instance.
  23185. @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
  23186. The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
  23187. Services}.
  23188. @end table
  23189. @end deftp
  23190. There is no @code{git-http-service-type}, currently; instead you can
  23191. create an @code{nginx-location-configuration} from a
  23192. @code{git-http-configuration} and then add that location to a web
  23193. server.
  23194. @deffn {Scheme Procedure} git-http-nginx-location-configuration @
  23195. [config=(git-http-configuration)]
  23196. Compute an @code{nginx-location-configuration} that corresponds to the
  23197. given Git http configuration. An example nginx service definition to
  23198. serve the default @file{/srv/git} over HTTPS might be:
  23199. @lisp
  23200. (service nginx-service-type
  23201. (nginx-configuration
  23202. (server-blocks
  23203. (list
  23204. (nginx-server-configuration
  23205. (listen '("443 ssl"))
  23206. (server-name "git.my-host.org")
  23207. (ssl-certificate
  23208. "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
  23209. (ssl-certificate-key
  23210. "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
  23211. (locations
  23212. (list
  23213. (git-http-nginx-location-configuration
  23214. (git-http-configuration (uri-path "/"))))))))))
  23215. @end lisp
  23216. This example assumes that you are using Let's Encrypt to get your TLS
  23217. certificate. @xref{Certificate Services}. The default @code{certbot}
  23218. service will redirect all HTTP traffic on @code{git.my-host.org} to
  23219. HTTPS@. You will also need to add an @code{fcgiwrap} proxy to your
  23220. system services. @xref{Web Services}.
  23221. @end deffn
  23222. @subsubheading Cgit Service
  23223. @cindex Cgit service
  23224. @cindex Git, web interface
  23225. @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
  23226. repositories written in C.
  23227. The following example will configure the service with default values.
  23228. By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
  23229. @lisp
  23230. (service cgit-service-type)
  23231. @end lisp
  23232. The @code{file-object} type designates either a file-like object
  23233. (@pxref{G-Expressions, file-like objects}) or a string.
  23234. @c %start of fragment
  23235. Available @code{cgit-configuration} fields are:
  23236. @deftypevr {@code{cgit-configuration} parameter} package package
  23237. The CGIT package.
  23238. @end deftypevr
  23239. @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
  23240. NGINX configuration.
  23241. @end deftypevr
  23242. @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
  23243. Specifies a command which will be invoked to format the content of about
  23244. pages (both top-level and for each repository).
  23245. Defaults to @samp{""}.
  23246. @end deftypevr
  23247. @deftypevr {@code{cgit-configuration} parameter} string agefile
  23248. Specifies a path, relative to each repository path, which can be used to
  23249. specify the date and time of the youngest commit in the repository.
  23250. Defaults to @samp{""}.
  23251. @end deftypevr
  23252. @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
  23253. Specifies a command that will be invoked for authenticating repository
  23254. access.
  23255. Defaults to @samp{""}.
  23256. @end deftypevr
  23257. @deftypevr {@code{cgit-configuration} parameter} string branch-sort
  23258. Flag which, when set to @samp{age}, enables date ordering in the branch
  23259. ref list, and when set @samp{name} enables ordering by branch name.
  23260. Defaults to @samp{"name"}.
  23261. @end deftypevr
  23262. @deftypevr {@code{cgit-configuration} parameter} string cache-root
  23263. Path used to store the cgit cache entries.
  23264. Defaults to @samp{"/var/cache/cgit"}.
  23265. @end deftypevr
  23266. @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
  23267. Number which specifies the time-to-live, in minutes, for the cached
  23268. version of repository pages accessed with a fixed SHA1.
  23269. Defaults to @samp{-1}.
  23270. @end deftypevr
  23271. @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
  23272. Number which specifies the time-to-live, in minutes, for the cached
  23273. version of repository pages accessed without a fixed SHA1.
  23274. Defaults to @samp{5}.
  23275. @end deftypevr
  23276. @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
  23277. Number which specifies the time-to-live, in minutes, for the cached
  23278. version of the repository summary page.
  23279. Defaults to @samp{5}.
  23280. @end deftypevr
  23281. @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
  23282. Number which specifies the time-to-live, in minutes, for the cached
  23283. version of the repository index page.
  23284. Defaults to @samp{5}.
  23285. @end deftypevr
  23286. @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
  23287. Number which specifies the time-to-live, in minutes, for the result of
  23288. scanning a path for Git repositories.
  23289. Defaults to @samp{15}.
  23290. @end deftypevr
  23291. @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
  23292. Number which specifies the time-to-live, in minutes, for the cached
  23293. version of the repository about page.
  23294. Defaults to @samp{15}.
  23295. @end deftypevr
  23296. @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
  23297. Number which specifies the time-to-live, in minutes, for the cached
  23298. version of snapshots.
  23299. Defaults to @samp{5}.
  23300. @end deftypevr
  23301. @deftypevr {@code{cgit-configuration} parameter} integer cache-size
  23302. The maximum number of entries in the cgit cache. When set to @samp{0},
  23303. caching is disabled.
  23304. Defaults to @samp{0}.
  23305. @end deftypevr
  23306. @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
  23307. Sort items in the repo list case sensitively.
  23308. Defaults to @samp{#t}.
  23309. @end deftypevr
  23310. @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
  23311. List of common prefixes which, when combined with a repository URL,
  23312. generates valid clone URLs for the repository.
  23313. Defaults to @samp{()}.
  23314. @end deftypevr
  23315. @deftypevr {@code{cgit-configuration} parameter} list clone-url
  23316. List of @code{clone-url} templates.
  23317. Defaults to @samp{()}.
  23318. @end deftypevr
  23319. @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
  23320. Command which will be invoked to format commit messages.
  23321. Defaults to @samp{""}.
  23322. @end deftypevr
  23323. @deftypevr {@code{cgit-configuration} parameter} string commit-sort
  23324. Flag which, when set to @samp{date}, enables strict date ordering in the
  23325. commit log, and when set to @samp{topo} enables strict topological
  23326. ordering.
  23327. Defaults to @samp{"git log"}.
  23328. @end deftypevr
  23329. @deftypevr {@code{cgit-configuration} parameter} file-object css
  23330. URL which specifies the css document to include in all cgit pages.
  23331. Defaults to @samp{"/share/cgit/cgit.css"}.
  23332. @end deftypevr
  23333. @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
  23334. Specifies a command which will be invoked to format names and email
  23335. address of committers, authors, and taggers, as represented in various
  23336. places throughout the cgit interface.
  23337. Defaults to @samp{""}.
  23338. @end deftypevr
  23339. @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
  23340. Flag which, when set to @samp{#t}, will make cgit generate a HTML
  23341. fragment suitable for embedding in other HTML pages.
  23342. Defaults to @samp{#f}.
  23343. @end deftypevr
  23344. @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
  23345. Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
  23346. commit history graph to the left of the commit messages in the
  23347. repository log page.
  23348. Defaults to @samp{#f}.
  23349. @end deftypevr
  23350. @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
  23351. Flag which, when set to @samp{#t}, allows all filter settings to be
  23352. overridden in repository-specific cgitrc files.
  23353. Defaults to @samp{#f}.
  23354. @end deftypevr
  23355. @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
  23356. Flag which, when set to @samp{#t}, allows users to follow a file in the
  23357. log view.
  23358. Defaults to @samp{#f}.
  23359. @end deftypevr
  23360. @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
  23361. If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
  23362. clones.
  23363. Defaults to @samp{#t}.
  23364. @end deftypevr
  23365. @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
  23366. Flag which, when set to @samp{#t}, will make cgit generate extra links
  23367. "summary", "commit", "tree" for each repo in the repository index.
  23368. Defaults to @samp{#f}.
  23369. @end deftypevr
  23370. @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
  23371. Flag which, when set to @samp{#t}, will make cgit display the owner of
  23372. each repo in the repository index.
  23373. Defaults to @samp{#t}.
  23374. @end deftypevr
  23375. @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
  23376. Flag which, when set to @samp{#t}, will make cgit print the number of
  23377. modified files for each commit on the repository log page.
  23378. Defaults to @samp{#f}.
  23379. @end deftypevr
  23380. @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
  23381. Flag which, when set to @samp{#t}, will make cgit print the number of
  23382. added and removed lines for each commit on the repository log page.
  23383. Defaults to @samp{#f}.
  23384. @end deftypevr
  23385. @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
  23386. Flag which, when set to @code{#t}, will make cgit display remote
  23387. branches in the summary and refs views.
  23388. Defaults to @samp{#f}.
  23389. @end deftypevr
  23390. @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
  23391. Flag which, when set to @code{1}, will make cgit use the subject of the
  23392. parent commit as link text when generating links to parent commits in
  23393. commit view.
  23394. Defaults to @samp{#f}.
  23395. @end deftypevr
  23396. @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
  23397. Flag which, when set to @samp{#t}, will make cgit use the subject of the
  23398. parent commit as link text when generating links to parent commits in
  23399. commit view.
  23400. Defaults to @samp{#f}.
  23401. @end deftypevr
  23402. @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
  23403. Flag which, when set to @samp{#t}, will make cgit generate linenumber
  23404. links for plaintext blobs printed in the tree view.
  23405. Defaults to @samp{#t}.
  23406. @end deftypevr
  23407. @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
  23408. Flag which, when set to @samp{#f}, will allow cgit to use Git config to
  23409. set any repo specific settings.
  23410. Defaults to @samp{#f}.
  23411. @end deftypevr
  23412. @deftypevr {@code{cgit-configuration} parameter} file-object favicon
  23413. URL used as link to a shortcut icon for cgit.
  23414. Defaults to @samp{"/favicon.ico"}.
  23415. @end deftypevr
  23416. @deftypevr {@code{cgit-configuration} parameter} string footer
  23417. The content of the file specified with this option will be included
  23418. verbatim at the bottom of all pages (i.e.@: it replaces the standard
  23419. "generated by..."@: message).
  23420. Defaults to @samp{""}.
  23421. @end deftypevr
  23422. @deftypevr {@code{cgit-configuration} parameter} string head-include
  23423. The content of the file specified with this option will be included
  23424. verbatim in the HTML HEAD section on all pages.
  23425. Defaults to @samp{""}.
  23426. @end deftypevr
  23427. @deftypevr {@code{cgit-configuration} parameter} string header
  23428. The content of the file specified with this option will be included
  23429. verbatim at the top of all pages.
  23430. Defaults to @samp{""}.
  23431. @end deftypevr
  23432. @deftypevr {@code{cgit-configuration} parameter} file-object include
  23433. Name of a configfile to include before the rest of the current config-
  23434. file is parsed.
  23435. Defaults to @samp{""}.
  23436. @end deftypevr
  23437. @deftypevr {@code{cgit-configuration} parameter} string index-header
  23438. The content of the file specified with this option will be included
  23439. verbatim above the repository index.
  23440. Defaults to @samp{""}.
  23441. @end deftypevr
  23442. @deftypevr {@code{cgit-configuration} parameter} string index-info
  23443. The content of the file specified with this option will be included
  23444. verbatim below the heading on the repository index page.
  23445. Defaults to @samp{""}.
  23446. @end deftypevr
  23447. @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
  23448. Flag which, if set to @samp{#t}, makes cgit print commit and tag times
  23449. in the servers timezone.
  23450. Defaults to @samp{#f}.
  23451. @end deftypevr
  23452. @deftypevr {@code{cgit-configuration} parameter} file-object logo
  23453. URL which specifies the source of an image which will be used as a logo
  23454. on all cgit pages.
  23455. Defaults to @samp{"/share/cgit/cgit.png"}.
  23456. @end deftypevr
  23457. @deftypevr {@code{cgit-configuration} parameter} string logo-link
  23458. URL loaded when clicking on the cgit logo image.
  23459. Defaults to @samp{""}.
  23460. @end deftypevr
  23461. @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
  23462. Command which will be invoked to format the Owner column of the main
  23463. page.
  23464. Defaults to @samp{""}.
  23465. @end deftypevr
  23466. @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
  23467. Number of items to display in atom feeds view.
  23468. Defaults to @samp{10}.
  23469. @end deftypevr
  23470. @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
  23471. Number of entries to list per page in "log" view.
  23472. Defaults to @samp{50}.
  23473. @end deftypevr
  23474. @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
  23475. Number of commit message characters to display in "log" view.
  23476. Defaults to @samp{80}.
  23477. @end deftypevr
  23478. @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
  23479. Specifies the number of entries to list per page on the repository index
  23480. page.
  23481. Defaults to @samp{50}.
  23482. @end deftypevr
  23483. @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
  23484. Specifies the maximum number of repo description characters to display
  23485. on the repository index page.
  23486. Defaults to @samp{80}.
  23487. @end deftypevr
  23488. @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
  23489. Specifies the maximum size of a blob to display HTML for in KBytes.
  23490. Defaults to @samp{0}.
  23491. @end deftypevr
  23492. @deftypevr {@code{cgit-configuration} parameter} string max-stats
  23493. Maximum statistics period. Valid values are @samp{week},@samp{month},
  23494. @samp{quarter} and @samp{year}.
  23495. Defaults to @samp{""}.
  23496. @end deftypevr
  23497. @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
  23498. Mimetype for the specified filename extension.
  23499. Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
  23500. "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
  23501. "image/png") (svg "image/svg+xml"))}.
  23502. @end deftypevr
  23503. @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
  23504. Specifies the file to use for automatic mimetype lookup.
  23505. Defaults to @samp{""}.
  23506. @end deftypevr
  23507. @deftypevr {@code{cgit-configuration} parameter} string module-link
  23508. Text which will be used as the formatstring for a hyperlink when a
  23509. submodule is printed in a directory listing.
  23510. Defaults to @samp{""}.
  23511. @end deftypevr
  23512. @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
  23513. If set to the value @samp{#t} caching will be disabled.
  23514. Defaults to @samp{#f}.
  23515. @end deftypevr
  23516. @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
  23517. If set to @samp{#t} showing full author email addresses will be
  23518. disabled.
  23519. Defaults to @samp{#f}.
  23520. @end deftypevr
  23521. @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
  23522. Flag which, when set to @samp{#t}, will make cgit omit the standard
  23523. header on all pages.
  23524. Defaults to @samp{#f}.
  23525. @end deftypevr
  23526. @deftypevr {@code{cgit-configuration} parameter} project-list project-list
  23527. A list of subdirectories inside of @code{repository-directory}, relative
  23528. to it, that should loaded as Git repositories. An empty list means that
  23529. all subdirectories will be loaded.
  23530. Defaults to @samp{()}.
  23531. @end deftypevr
  23532. @deftypevr {@code{cgit-configuration} parameter} file-object readme
  23533. Text which will be used as default value for @code{cgit-repo-readme}.
  23534. Defaults to @samp{""}.
  23535. @end deftypevr
  23536. @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
  23537. If set to @code{#t} and @code{repository-directory} is enabled, if any
  23538. repositories are found with a suffix of @code{.git}, this suffix will be
  23539. removed for the URL and name.
  23540. Defaults to @samp{#f}.
  23541. @end deftypevr
  23542. @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
  23543. Maximum number of files to consider when detecting renames.
  23544. Defaults to @samp{-1}.
  23545. @end deftypevr
  23546. @deftypevr {@code{cgit-configuration} parameter} string repository-sort
  23547. The way in which repositories in each section are sorted.
  23548. Defaults to @samp{""}.
  23549. @end deftypevr
  23550. @deftypevr {@code{cgit-configuration} parameter} robots-list robots
  23551. Text used as content for the @code{robots} meta-tag.
  23552. Defaults to @samp{("noindex" "nofollow")}.
  23553. @end deftypevr
  23554. @deftypevr {@code{cgit-configuration} parameter} string root-desc
  23555. Text printed below the heading on the repository index page.
  23556. Defaults to @samp{"a fast webinterface for the git dscm"}.
  23557. @end deftypevr
  23558. @deftypevr {@code{cgit-configuration} parameter} string root-readme
  23559. The content of the file specified with this option will be included
  23560. verbatim below the ``about'' link on the repository index page.
  23561. Defaults to @samp{""}.
  23562. @end deftypevr
  23563. @deftypevr {@code{cgit-configuration} parameter} string root-title
  23564. Text printed as heading on the repository index page.
  23565. Defaults to @samp{""}.
  23566. @end deftypevr
  23567. @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
  23568. If set to @samp{#t} and repository-directory is enabled,
  23569. repository-directory will recurse into directories whose name starts
  23570. with a period. Otherwise, repository-directory will stay away from such
  23571. directories, considered as ``hidden''. Note that this does not apply to
  23572. the @file{.git} directory in non-bare repos.
  23573. Defaults to @samp{#f}.
  23574. @end deftypevr
  23575. @deftypevr {@code{cgit-configuration} parameter} list snapshots
  23576. Text which specifies the default set of snapshot formats that cgit
  23577. generates links for.
  23578. Defaults to @samp{()}.
  23579. @end deftypevr
  23580. @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
  23581. Name of the directory to scan for repositories (represents
  23582. @code{scan-path}).
  23583. Defaults to @samp{"/srv/git"}.
  23584. @end deftypevr
  23585. @deftypevr {@code{cgit-configuration} parameter} string section
  23586. The name of the current repository section - all repositories defined
  23587. after this option will inherit the current section name.
  23588. Defaults to @samp{""}.
  23589. @end deftypevr
  23590. @deftypevr {@code{cgit-configuration} parameter} string section-sort
  23591. Flag which, when set to @samp{1}, will sort the sections on the
  23592. repository listing by name.
  23593. Defaults to @samp{""}.
  23594. @end deftypevr
  23595. @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
  23596. A number which, if defined prior to repository-directory, specifies how
  23597. many path elements from each repo path to use as a default section name.
  23598. Defaults to @samp{0}.
  23599. @end deftypevr
  23600. @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
  23601. If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
  23602. default.
  23603. Defaults to @samp{#f}.
  23604. @end deftypevr
  23605. @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
  23606. Specifies a command which will be invoked to format plaintext blobs in
  23607. the tree view.
  23608. Defaults to @samp{""}.
  23609. @end deftypevr
  23610. @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
  23611. Specifies the number of branches to display in the repository ``summary''
  23612. view.
  23613. Defaults to @samp{10}.
  23614. @end deftypevr
  23615. @deftypevr {@code{cgit-configuration} parameter} integer summary-log
  23616. Specifies the number of log entries to display in the repository
  23617. ``summary'' view.
  23618. Defaults to @samp{10}.
  23619. @end deftypevr
  23620. @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
  23621. Specifies the number of tags to display in the repository ``summary''
  23622. view.
  23623. Defaults to @samp{10}.
  23624. @end deftypevr
  23625. @deftypevr {@code{cgit-configuration} parameter} string strict-export
  23626. Filename which, if specified, needs to be present within the repository
  23627. for cgit to allow access to that repository.
  23628. Defaults to @samp{""}.
  23629. @end deftypevr
  23630. @deftypevr {@code{cgit-configuration} parameter} string virtual-root
  23631. URL which, if specified, will be used as root for all cgit links.
  23632. Defaults to @samp{"/"}.
  23633. @end deftypevr
  23634. @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
  23635. A list of @dfn{cgit-repo} records to use with config.
  23636. Defaults to @samp{()}.
  23637. Available @code{repository-cgit-configuration} fields are:
  23638. @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
  23639. A mask of snapshot formats for this repo that cgit generates links for,
  23640. restricted by the global @code{snapshots} setting.
  23641. Defaults to @samp{()}.
  23642. @end deftypevr
  23643. @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
  23644. Override the default @code{source-filter}.
  23645. Defaults to @samp{""}.
  23646. @end deftypevr
  23647. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
  23648. The relative URL used to access the repository.
  23649. Defaults to @samp{""}.
  23650. @end deftypevr
  23651. @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
  23652. Override the default @code{about-filter}.
  23653. Defaults to @samp{""}.
  23654. @end deftypevr
  23655. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
  23656. Flag which, when set to @samp{age}, enables date ordering in the branch
  23657. ref list, and when set to @samp{name} enables ordering by branch name.
  23658. Defaults to @samp{""}.
  23659. @end deftypevr
  23660. @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
  23661. A list of URLs which can be used to clone repo.
  23662. Defaults to @samp{()}.
  23663. @end deftypevr
  23664. @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
  23665. Override the default @code{commit-filter}.
  23666. Defaults to @samp{""}.
  23667. @end deftypevr
  23668. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
  23669. Flag which, when set to @samp{date}, enables strict date ordering in the
  23670. commit log, and when set to @samp{topo} enables strict topological
  23671. ordering.
  23672. Defaults to @samp{""}.
  23673. @end deftypevr
  23674. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
  23675. The name of the default branch for this repository. If no such branch
  23676. exists in the repository, the first branch name (when sorted) is used as
  23677. default instead. By default branch pointed to by HEAD, or ``master'' if
  23678. there is no suitable HEAD.
  23679. Defaults to @samp{""}.
  23680. @end deftypevr
  23681. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
  23682. The value to show as repository description.
  23683. Defaults to @samp{""}.
  23684. @end deftypevr
  23685. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
  23686. The value to show as repository homepage.
  23687. Defaults to @samp{""}.
  23688. @end deftypevr
  23689. @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
  23690. Override the default @code{email-filter}.
  23691. Defaults to @samp{""}.
  23692. @end deftypevr
  23693. @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
  23694. A flag which can be used to disable the global setting
  23695. @code{enable-commit-graph?}.
  23696. Defaults to @samp{disabled}.
  23697. @end deftypevr
  23698. @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
  23699. A flag which can be used to disable the global setting
  23700. @code{enable-log-filecount?}.
  23701. Defaults to @samp{disabled}.
  23702. @end deftypevr
  23703. @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
  23704. A flag which can be used to disable the global setting
  23705. @code{enable-log-linecount?}.
  23706. Defaults to @samp{disabled}.
  23707. @end deftypevr
  23708. @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
  23709. Flag which, when set to @code{#t}, will make cgit display remote
  23710. branches in the summary and refs views.
  23711. Defaults to @samp{disabled}.
  23712. @end deftypevr
  23713. @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
  23714. A flag which can be used to override the global setting
  23715. @code{enable-subject-links?}.
  23716. Defaults to @samp{disabled}.
  23717. @end deftypevr
  23718. @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
  23719. A flag which can be used to override the global setting
  23720. @code{enable-html-serving?}.
  23721. Defaults to @samp{disabled}.
  23722. @end deftypevr
  23723. @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
  23724. Flag which, when set to @code{#t}, hides the repository from the
  23725. repository index.
  23726. Defaults to @samp{#f}.
  23727. @end deftypevr
  23728. @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
  23729. Flag which, when set to @samp{#t}, ignores the repository.
  23730. Defaults to @samp{#f}.
  23731. @end deftypevr
  23732. @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
  23733. URL which specifies the source of an image which will be used as a logo
  23734. on this repo’s pages.
  23735. Defaults to @samp{""}.
  23736. @end deftypevr
  23737. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
  23738. URL loaded when clicking on the cgit logo image.
  23739. Defaults to @samp{""}.
  23740. @end deftypevr
  23741. @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
  23742. Override the default @code{owner-filter}.
  23743. Defaults to @samp{""}.
  23744. @end deftypevr
  23745. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
  23746. Text which will be used as the formatstring for a hyperlink when a
  23747. submodule is printed in a directory listing. The arguments for the
  23748. formatstring are the path and SHA1 of the submodule commit.
  23749. Defaults to @samp{""}.
  23750. @end deftypevr
  23751. @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
  23752. Text which will be used as the formatstring for a hyperlink when a
  23753. submodule with the specified subdirectory path is printed in a directory
  23754. listing.
  23755. Defaults to @samp{()}.
  23756. @end deftypevr
  23757. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
  23758. Override the default maximum statistics period.
  23759. Defaults to @samp{""}.
  23760. @end deftypevr
  23761. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
  23762. The value to show as repository name.
  23763. Defaults to @samp{""}.
  23764. @end deftypevr
  23765. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
  23766. A value used to identify the owner of the repository.
  23767. Defaults to @samp{""}.
  23768. @end deftypevr
  23769. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
  23770. An absolute path to the repository directory.
  23771. Defaults to @samp{""}.
  23772. @end deftypevr
  23773. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
  23774. A path (relative to repo) which specifies a file to include verbatim as
  23775. the ``About'' page for this repo.
  23776. Defaults to @samp{""}.
  23777. @end deftypevr
  23778. @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
  23779. The name of the current repository section - all repositories defined
  23780. after this option will inherit the current section name.
  23781. Defaults to @samp{""}.
  23782. @end deftypevr
  23783. @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
  23784. Extra options will be appended to cgitrc file.
  23785. Defaults to @samp{()}.
  23786. @end deftypevr
  23787. @end deftypevr
  23788. @deftypevr {@code{cgit-configuration} parameter} list extra-options
  23789. Extra options will be appended to cgitrc file.
  23790. Defaults to @samp{()}.
  23791. @end deftypevr
  23792. @c %end of fragment
  23793. However, it could be that you just want to get a @code{cgitrc} up and
  23794. running. In that case, you can pass an @code{opaque-cgit-configuration}
  23795. as a record to @code{cgit-service-type}. As its name indicates, an
  23796. opaque configuration does not have easy reflective capabilities.
  23797. Available @code{opaque-cgit-configuration} fields are:
  23798. @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
  23799. The cgit package.
  23800. @end deftypevr
  23801. @deftypevr {@code{opaque-cgit-configuration} parameter} string string
  23802. The contents of the @code{cgitrc}, as a string.
  23803. @end deftypevr
  23804. For example, if your @code{cgitrc} is just the empty string, you
  23805. could instantiate a cgit service like this:
  23806. @lisp
  23807. (service cgit-service-type
  23808. (opaque-cgit-configuration
  23809. (cgitrc "")))
  23810. @end lisp
  23811. @subsubheading Gitolite Service
  23812. @cindex Gitolite service
  23813. @cindex Git, hosting
  23814. @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
  23815. repositories on a central server.
  23816. Gitolite can handle multiple repositories and users, and supports flexible
  23817. configuration of the permissions for the users on the repositories.
  23818. The following example will configure Gitolite using the default @code{git}
  23819. user, and the provided SSH public key.
  23820. @lisp
  23821. (service gitolite-service-type
  23822. (gitolite-configuration
  23823. (admin-pubkey (plain-file
  23824. "yourname.pub"
  23825. "ssh-rsa AAAA... guix@@example.com"))))
  23826. @end lisp
  23827. Gitolite is configured through a special admin repository which you can clone,
  23828. for example, if you setup Gitolite on @code{example.com}, you would run the
  23829. following command to clone the admin repository.
  23830. @example
  23831. git clone git@@example.com:gitolite-admin
  23832. @end example
  23833. When the Gitolite service is activated, the provided @code{admin-pubkey} will
  23834. be inserted in to the @file{keydir} directory in the gitolite-admin
  23835. repository. If this results in a change in the repository, it will be
  23836. committed using the message ``gitolite setup by GNU Guix''.
  23837. @deftp {Data Type} gitolite-configuration
  23838. Data type representing the configuration for @code{gitolite-service-type}.
  23839. @table @asis
  23840. @item @code{package} (default: @var{gitolite})
  23841. Gitolite package to use.
  23842. @item @code{user} (default: @var{git})
  23843. User to use for Gitolite. This will be user that you use when accessing
  23844. Gitolite over SSH.
  23845. @item @code{group} (default: @var{git})
  23846. Group to use for Gitolite.
  23847. @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
  23848. Directory in which to store the Gitolite configuration and repositories.
  23849. @item @code{rc-file} (default: @var{(gitolite-rc-file)})
  23850. A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
  23851. representing the configuration for Gitolite.
  23852. @item @code{admin-pubkey} (default: @var{#f})
  23853. A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
  23854. setup Gitolite. This will be inserted in to the @file{keydir} directory
  23855. within the gitolite-admin repository.
  23856. To specify the SSH key as a string, use the @code{plain-file} function.
  23857. @lisp
  23858. (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
  23859. @end lisp
  23860. @end table
  23861. @end deftp
  23862. @deftp {Data Type} gitolite-rc-file
  23863. Data type representing the Gitolite RC file.
  23864. @table @asis
  23865. @item @code{umask} (default: @code{#o0077})
  23866. This controls the permissions Gitolite sets on the repositories and their
  23867. contents.
  23868. A value like @code{#o0027} will give read access to the group used by Gitolite
  23869. (by default: @code{git}). This is necessary when using Gitolite with software
  23870. like cgit or gitweb.
  23871. @item @code{git-config-keys} (default: @code{""})
  23872. Gitolite allows you to set git config values using the @samp{config}
  23873. keyword. This setting allows control over the config keys to accept.
  23874. @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
  23875. Set the role names allowed to be used by users running the perms command.
  23876. @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
  23877. This setting controls the commands and features to enable within Gitolite.
  23878. @end table
  23879. @end deftp
  23880. @node Game Services
  23881. @subsection Game Services
  23882. @subsubheading The Battle for Wesnoth Service
  23883. @cindex wesnothd
  23884. @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
  23885. based tactical strategy game, with several single player campaigns, and
  23886. multiplayer games (both networked and local).
  23887. @defvar {Scheme Variable} wesnothd-service-type
  23888. Service type for the wesnothd service. Its value must be a
  23889. @code{wesnothd-configuration} object. To run wesnothd in the default
  23890. configuration, instantiate it as:
  23891. @lisp
  23892. (service wesnothd-service-type)
  23893. @end lisp
  23894. @end defvar
  23895. @deftp {Data Type} wesnothd-configuration
  23896. Data type representing the configuration of @command{wesnothd}.
  23897. @table @asis
  23898. @item @code{package} (default: @code{wesnoth-server})
  23899. The wesnoth server package to use.
  23900. @item @code{port} (default: @code{15000})
  23901. The port to bind the server to.
  23902. @end table
  23903. @end deftp
  23904. @node PAM Mount Service
  23905. @subsection PAM Mount Service
  23906. @cindex pam-mount
  23907. The @code{(gnu services pam-mount)} module provides a service allowing
  23908. users to mount volumes when they log in. It should be able to mount any
  23909. volume format supported by the system.
  23910. @defvar {Scheme Variable} pam-mount-service-type
  23911. Service type for PAM Mount support.
  23912. @end defvar
  23913. @deftp {Data Type} pam-mount-configuration
  23914. Data type representing the configuration of PAM Mount.
  23915. It takes the following parameters:
  23916. @table @asis
  23917. @item @code{rules}
  23918. The configuration rules that will be used to generate
  23919. @file{/etc/security/pam_mount.conf.xml}.
  23920. The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
  23921. Guile Reference Manual}), and the default ones don't mount anything for
  23922. anyone at login:
  23923. @lisp
  23924. `((debug (@@ (enable "0")))
  23925. (mntoptions (@@ (allow ,(string-join
  23926. '("nosuid" "nodev" "loop"
  23927. "encryption" "fsck" "nonempty"
  23928. "allow_root" "allow_other")
  23929. ","))))
  23930. (mntoptions (@@ (require "nosuid,nodev")))
  23931. (logout (@@ (wait "0")
  23932. (hup "0")
  23933. (term "no")
  23934. (kill "no")))
  23935. (mkmountpoint (@@ (enable "1")
  23936. (remove "true"))))
  23937. @end lisp
  23938. Some @code{volume} elements must be added to automatically mount volumes
  23939. at login. Here's an example allowing the user @code{alice} to mount her
  23940. encrypted @env{HOME} directory and allowing the user @code{bob} to mount
  23941. the partition where he stores his data:
  23942. @lisp
  23943. (define pam-mount-rules
  23944. `((debug (@@ (enable "0")))
  23945. (volume (@@ (user "alice")
  23946. (fstype "crypt")
  23947. (path "/dev/sda2")
  23948. (mountpoint "/home/alice")))
  23949. (volume (@@ (user "bob")
  23950. (fstype "auto")
  23951. (path "/dev/sdb3")
  23952. (mountpoint "/home/bob/data")
  23953. (options "defaults,autodefrag,compress")))
  23954. (mntoptions (@@ (allow ,(string-join
  23955. '("nosuid" "nodev" "loop"
  23956. "encryption" "fsck" "nonempty"
  23957. "allow_root" "allow_other")
  23958. ","))))
  23959. (mntoptions (@@ (require "nosuid,nodev")))
  23960. (logout (@@ (wait "0")
  23961. (hup "0")
  23962. (term "no")
  23963. (kill "no")))
  23964. (mkmountpoint (@@ (enable "1")
  23965. (remove "true")))))
  23966. (service pam-mount-service-type
  23967. (pam-mount-configuration
  23968. (rules pam-mount-rules)))
  23969. @end lisp
  23970. The complete list of possible options can be found in the man page for
  23971. @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
  23972. @end table
  23973. @end deftp
  23974. @node Guix Services
  23975. @subsection Guix Services
  23976. @subsubheading Guix Build Coordinator
  23977. The @uref{https://git.cbaines.net/guix/build-coordinator/,Guix Build
  23978. Coordinator} aids in distributing derivation builds among machines
  23979. running an @dfn{agent}. The build daemon is still used to build the
  23980. derivations, but the Guix Build Coordinator manages allocating builds
  23981. and working with the results.
  23982. @quotation Note
  23983. This service is considered experimental. Configuration options may be
  23984. changed in a backwards-incompatible manner, and not all features have
  23985. been thorougly tested.
  23986. @end quotation
  23987. The Guix Build Coordinator consists of one @dfn{coordinator}, and one or
  23988. more connected @dfn{agent} processes. The coordinator process handles
  23989. clients submitting builds, and allocating builds to agents. The agent
  23990. processes talk to a build daemon to actually perform the builds, then
  23991. send the results back to the coordinator.
  23992. There is a script to run the coordinator component of the Guix Build
  23993. Coordinator, but the Guix service uses a custom Guile script instead, to
  23994. provide better integration with G-expressions used in the configuration.
  23995. @defvar {Scheme Variable} guix-build-coordinator-service-type
  23996. Service type for the Guix Build Coordinator. Its value must be a
  23997. @code{guix-build-coordinator-configuration} object.
  23998. @end defvar
  23999. @deftp {Data Type} guix-build-coordinator-configuration
  24000. Data type representing the configuration of the Guix Build Coordinator.
  24001. @table @asis
  24002. @item @code{package} (default: @code{guix-build-coordinator})
  24003. The Guix Build Coordinator package to use.
  24004. @item @code{user} (default: @code{"guix-build-coordinator"})
  24005. The system user to run the service as.
  24006. @item @code{group} (default: @code{"guix-build-coordinator"})
  24007. The system group to run the service as.
  24008. @item @code{database-uri-string} (default: @code{"sqlite:///var/lib/guix-build-coordinator/guix_build_coordinator.db"})
  24009. The URI to use for the database.
  24010. @item @code{agent-communication-uri} (default: @code{"http://0.0.0.0:8745"})
  24011. The URI describing how to listen to requests from agent processes.
  24012. @item @code{client-communication-uri} (default: @code{"http://127.0.0.1:8746"})
  24013. The URI describing how to listen to requests from clients. The client
  24014. API allows submitting builds and currently isn't authenticated, so take
  24015. care when configuring this value.
  24016. @item @code{allocation-strategy} (default: @code{#~basic-build-allocation-strategy})
  24017. A G-expression for the allocation strategy to be used. This is a
  24018. procedure that takes the datastore as an argument and populates the
  24019. allocation plan in the database.
  24020. @item @code{hooks} (default: @var{'()})
  24021. An association list of hooks. These provide a way to execute arbitrary
  24022. code upon certain events, like a build result being processed.
  24023. @item @code{guile} (default: @code{guile-3.0-latest})
  24024. The Guile package with which to run the Guix Build Coordinator.
  24025. @end table
  24026. @end deftp
  24027. @defvar {Scheme Variable} guix-build-coordinator-agent-service-type
  24028. Service type for a Guix Build Coordinator agent. Its value must be a
  24029. @code{guix-build-coordinator-agent-configuration} object.
  24030. @end defvar
  24031. @deftp {Data Type} guix-build-coordinator-agent-configuration
  24032. Data type representing the configuration a Guix Build Coordinator agent.
  24033. @table @asis
  24034. @item @code{package} (default: @code{guix-build-coordinator})
  24035. The Guix Build Coordinator package to use.
  24036. @item @code{user} (default: @code{"guix-build-coordinator-agent"})
  24037. The system user to run the service as.
  24038. @item @code{coordinator} (default: @code{"http://localhost:8745"})
  24039. The URI to use when connecting to the coordinator.
  24040. @item @code{authentication}
  24041. Record describing how this agent should authenticate with the
  24042. coordinator. Possible record types are described below.
  24043. @item @code{systems} (default: @code{#f})
  24044. The systems for which this agent should fetch builds. The agent process
  24045. will use the current system it's running on as the default.
  24046. @item @code{max-parallel-builds} (default: @code{1})
  24047. The number of builds to perform in parallel.
  24048. @item @code{derivation-substitute-urls} (default: @code{#f})
  24049. URLs from which to attempt to fetch substitutes for derivations, if the
  24050. derivations aren't already available.
  24051. @item @code{non-derivation-substitute-urls} (default: @code{#f})
  24052. URLs from which to attempt to fetch substitutes for build inputs, if the
  24053. input store items aren't already available.
  24054. @end table
  24055. @end deftp
  24056. @deftp {Data Type} guix-build-coordinator-agent-password-auth
  24057. Data type representing an agent authenticating with a coordinator via a
  24058. UUID and password.
  24059. @table @asis
  24060. @item @code{uuid}
  24061. The UUID of the agent. This should be generated by the coordinator
  24062. process, stored in the coordinator database, and used by the intended
  24063. agent.
  24064. @item @code{password}
  24065. The password to use when connecting to the coordinator.
  24066. @end table
  24067. @end deftp
  24068. @deftp {Data Type} guix-build-coordinator-agent-password-file-auth
  24069. Data type representing an agent authenticating with a coordinator via a
  24070. UUID and password read from a file.
  24071. @table @asis
  24072. @item @code{uuid}
  24073. The UUID of the agent. This should be generated by the coordinator
  24074. process, stored in the coordinator database, and used by the intended
  24075. agent.
  24076. @item @code{password-file}
  24077. A file containing the password to use when connecting to the
  24078. coordinator.
  24079. @end table
  24080. @end deftp
  24081. @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth
  24082. Data type representing an agent authenticating with a coordinator via a
  24083. dyanmic auth token and agent name.
  24084. @table @asis
  24085. @item @code{agent-name}
  24086. Name of an agent, this is used to match up to an existing entry in the
  24087. database if there is one. When no existing entry is found, a new entry
  24088. is automatically added.
  24089. @item @code{token}
  24090. Dynamic auth token, this is created and stored in the coordinator
  24091. database, and is used by the agent to authenticate.
  24092. @end table
  24093. @end deftp
  24094. @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth-with-file
  24095. Data type representing an agent authenticating with a coordinator via a
  24096. dyanmic auth token read from a file and agent name.
  24097. @table @asis
  24098. @item @code{agent-name}
  24099. Name of an agent, this is used to match up to an existing entry in the
  24100. database if there is one. When no existing entry is found, a new entry
  24101. is automatically added.
  24102. @item @code{token-file}
  24103. File containing the dynamic auth token, this is created and stored in
  24104. the coordinator database, and is used by the agent to authenticate.
  24105. @end table
  24106. @end deftp
  24107. The Guix Build Coordinator package contains a script to query an
  24108. instance of the Guix Data Service for derivations to build, and then
  24109. submit builds for those derivations to the coordinator. The service
  24110. type below assists in running this script. This is an additional tool
  24111. that may be useful when building derivations contained within an
  24112. instance of the Guix Data Service.
  24113. @defvar {Scheme Variable} guix-build-coordinator-queue-builds-service-type
  24114. Service type for the
  24115. guix-build-coordinator-queue-builds-from-guix-data-service script. Its
  24116. value must be a @code{guix-build-coordinator-queue-builds-configuration}
  24117. object.
  24118. @end defvar
  24119. @deftp {Data Type} guix-build-coordinator-queue-builds-configuration
  24120. Data type representing the options to the queue builds from guix data
  24121. service script.
  24122. @table @asis
  24123. @item @code{package} (default: @code{guix-build-coordinator})
  24124. The Guix Build Coordinator package to use.
  24125. @item @code{user} (default: @code{"guix-build-coordinator-queue-builds"})
  24126. The system user to run the service as.
  24127. @item @code{coordinator} (default: @code{"http://localhost:8745"})
  24128. The URI to use when connecting to the coordinator.
  24129. @item @code{systems} (default: @code{#f})
  24130. The systems for which to fetch derivations to build.
  24131. @item @code{systems-and-targets} (default: @code{#f})
  24132. An association list of system and target pairs for which to fetch
  24133. derivations to build.
  24134. @item @code{guix-data-service} (default: @code{"https://data.guix.gnu.org"})
  24135. The Guix Data Service instance from which to query to find out about
  24136. derivations to build.
  24137. @item @code{processed-commits-file} (default: @code{"/var/cache/guix-build-coordinator-queue-builds/processed-commits"})
  24138. A file to record which commits have been processed, to avoid needlessly
  24139. processing them again if the service is restarted.
  24140. @end table
  24141. @end deftp
  24142. @subsubheading Guix Data Service
  24143. The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
  24144. and provides data about GNU Guix. This includes information about
  24145. packages, derivations and lint warnings.
  24146. The data is stored in a PostgreSQL database, and available through a web
  24147. interface.
  24148. @defvar {Scheme Variable} guix-data-service-type
  24149. Service type for the Guix Data Service. Its value must be a
  24150. @code{guix-data-service-configuration} object. The service optionally
  24151. extends the getmail service, as the guix-commits mailing list is used to
  24152. find out about changes in the Guix git repository.
  24153. @end defvar
  24154. @deftp {Data Type} guix-data-service-configuration
  24155. Data type representing the configuration of the Guix Data Service.
  24156. @table @asis
  24157. @item @code{package} (default: @code{guix-data-service})
  24158. The Guix Data Service package to use.
  24159. @item @code{user} (default: @code{"guix-data-service"})
  24160. The system user to run the service as.
  24161. @item @code{group} (default: @code{"guix-data-service"})
  24162. The system group to run the service as.
  24163. @item @code{port} (default: @code{8765})
  24164. The port to bind the web service to.
  24165. @item @code{host} (default: @code{"127.0.0.1"})
  24166. The host to bind the web service to.
  24167. @item @code{getmail-idle-mailboxes} (default: @code{#f})
  24168. If set, this is the list of mailboxes that the getmail service will be
  24169. configured to listen to.
  24170. @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
  24171. If set, this is the @code{getmail-retriever-configuration} object with
  24172. which to configure getmail to fetch mail from the guix-commits mailing
  24173. list.
  24174. @item @code{extra-options} (default: @var{'()})
  24175. Extra command line options for @code{guix-data-service}.
  24176. @item @code{extra-process-jobs-options} (default: @var{'()})
  24177. Extra command line options for @code{guix-data-service-process-jobs}.
  24178. @end table
  24179. @end deftp
  24180. @node Linux Services
  24181. @subsection Linux Services
  24182. @cindex oom
  24183. @cindex out of memory killer
  24184. @cindex earlyoom
  24185. @cindex early out of memory daemon
  24186. @subsubheading Early OOM Service
  24187. @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
  24188. Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
  24189. space and provides a more responsive and configurable alternative to the
  24190. in-kernel OOM killer. It is useful to prevent the system from becoming
  24191. unresponsive when it runs out of memory.
  24192. @deffn {Scheme Variable} earlyoom-service-type
  24193. The service type for running @command{earlyoom}, the Early OOM daemon.
  24194. Its value must be a @code{earlyoom-configuration} object, described
  24195. below. The service can be instantiated in its default configuration
  24196. with:
  24197. @lisp
  24198. (service earlyoom-service-type)
  24199. @end lisp
  24200. @end deffn
  24201. @deftp {Data Type} earlyoom-configuration
  24202. This is the configuration record for the @code{earlyoom-service-type}.
  24203. @table @asis
  24204. @item @code{earlyoom} (default: @var{earlyoom})
  24205. The Earlyoom package to use.
  24206. @item @code{minimum-available-memory} (default: @code{10})
  24207. The threshold for the minimum @emph{available} memory, in percentages.
  24208. @item @code{minimum-free-swap} (default: @code{10})
  24209. The threshold for the minimum free swap memory, in percentages.
  24210. @item @code{prefer-regexp} (default: @code{#f})
  24211. A regular expression (as a string) to match the names of the processes
  24212. that should be preferably killed.
  24213. @item @code{avoid-regexp} (default: @code{#f})
  24214. A regular expression (as a string) to match the names of the processes
  24215. that should @emph{not} be killed.
  24216. @item @code{memory-report-interval} (default: @code{0})
  24217. The interval in seconds at which a memory report is printed. It is
  24218. disabled by default.
  24219. @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
  24220. A boolean indicating whether the positive adjustments set in
  24221. @file{/proc/*/oom_score_adj} should be ignored.
  24222. @item @code{show-debug-messages?} (default: @code{#f})
  24223. A boolean indicating whether debug messages should be printed. The logs
  24224. are saved at @file{/var/log/earlyoom.log}.
  24225. @item @code{send-notification-command} (default: @code{#f})
  24226. This can be used to provide a custom command used for sending
  24227. notifications.
  24228. @end table
  24229. @end deftp
  24230. @cindex modprobe
  24231. @cindex kernel module loader
  24232. @subsubheading Kernel Module Loader Service
  24233. The kernel module loader service allows one to load loadable kernel
  24234. modules at boot. This is especially useful for modules that don't
  24235. autoload and need to be manually loaded, as it's the case with
  24236. @code{ddcci}.
  24237. @deffn {Scheme Variable} kernel-module-loader-service-type
  24238. The service type for loading loadable kernel modules at boot with
  24239. @command{modprobe}. Its value must be a list of strings representing
  24240. module names. For example loading the drivers provided by
  24241. @code{ddcci-driver-linux}, in debugging mode by passing some module
  24242. parameters, can be done as follow:
  24243. @lisp
  24244. (use-modules (gnu) (gnu services))
  24245. (use-package-modules linux)
  24246. (use-service-modules linux)
  24247. (define ddcci-config
  24248. (plain-file "ddcci.conf"
  24249. "options ddcci dyndbg delay=120"))
  24250. (operating-system
  24251. ...
  24252. (services (cons* (service kernel-module-loader-service-type
  24253. '("ddcci" "ddcci_backlight"))
  24254. (simple-service 'ddcci-config etc-service-type
  24255. (list `("modprobe.d/ddcci.conf"
  24256. ,ddcci-config)))
  24257. %base-services))
  24258. (kernel-loadable-modules (list ddcci-driver-linux)))
  24259. @end lisp
  24260. @end deffn
  24261. @cindex zram
  24262. @cindex compressed swap
  24263. @cindex Compressed RAM-based block devices
  24264. @subsubheading Zram Device Service
  24265. The Zram device service provides a compressed swap device in system
  24266. memory. The Linux Kernel documentation has more information about
  24267. @uref{https://www.kernel.org/doc/html/latest/admin-guide/blockdev/zram.html,zram}
  24268. devices.
  24269. @deffn {Scheme Variable} zram-device-service-type
  24270. This service creates the zram block device, formats it as swap and
  24271. enables it as a swap device. The service's value is a
  24272. @code{zram-device-configuration} record.
  24273. @deftp {Data Type} zram-device-configuration
  24274. This is the data type representing the configuration for the zram-device
  24275. service.
  24276. @table @asis
  24277. @item @code{size} (default @code{"1G"})
  24278. This is the amount of space you wish to provide for the zram device. It
  24279. accepts a string and can be a number of bytes or use a suffix, eg.:
  24280. @code{"512M"} or @code{1024000}.
  24281. @item @code{compression-algorithm} (default @code{'lzo})
  24282. This is the compression algorithm you wish to use. It is difficult to
  24283. list all the possible compression options, but common ones supported by
  24284. Guix's Linux Libre Kernel include @code{'lzo}, @code{'lz4} and @code{'zstd}.
  24285. @item @code{memory-limit} (default @code{0})
  24286. This is the maximum amount of memory which the zram device can use.
  24287. Setting it to '0' disables the limit. While it is generally expected
  24288. that compression will be 2:1, it is possible that uncompressable data
  24289. can be written to swap and this is a method to limit how much memory can
  24290. be used. It accepts a string and can be a number of bytes or use a
  24291. suffix, eg.: @code{"2G"}.
  24292. @item @code{priority} (default @code{-1})
  24293. This is the priority of the swap device created from the zram device.
  24294. @code{swapon} accepts values between -1 and 32767, with higher values
  24295. indicating higher priority. Higher priority swap will generally be used
  24296. first.
  24297. @end table
  24298. @end deftp
  24299. @end deffn
  24300. @node Hurd Services
  24301. @subsection Hurd Services
  24302. @defvr {Scheme Variable} hurd-console-service-type
  24303. This service starts the fancy @code{VGA} console client on the Hurd.
  24304. The service's value is a @code{hurd-console-configuration} record.
  24305. @end defvr
  24306. @deftp {Data Type} hurd-console-configuration
  24307. This is the data type representing the configuration for the
  24308. hurd-console-service.
  24309. @table @asis
  24310. @item @code{hurd} (default: @var{hurd})
  24311. The Hurd package to use.
  24312. @end table
  24313. @end deftp
  24314. @defvr {Scheme Variable} hurd-getty-service-type
  24315. This service starts a tty using the Hurd @code{getty} program.
  24316. The service's value is a @code{hurd-getty-configuration} record.
  24317. @end defvr
  24318. @deftp {Data Type} hurd-getty-configuration
  24319. This is the data type representing the configuration for the
  24320. hurd-getty-service.
  24321. @table @asis
  24322. @item @code{hurd} (default: @var{hurd})
  24323. The Hurd package to use.
  24324. @item @code{tty}
  24325. The name of the console this Getty runs on---e.g., @code{"tty1"}.
  24326. @item @code{baud-rate} (default: @code{38400})
  24327. An integer specifying the baud rate of the tty.
  24328. @end table
  24329. @end deftp
  24330. @node Miscellaneous Services
  24331. @subsection Miscellaneous Services
  24332. @cindex fingerprint
  24333. @subsubheading Fingerprint Service
  24334. The @code{(gnu services authentication)} module provides a DBus service to
  24335. read and identify fingerprints via a fingerprint sensor.
  24336. @defvr {Scheme Variable} fprintd-service-type
  24337. The service type for @command{fprintd}, which provides the fingerprint
  24338. reading capability.
  24339. @lisp
  24340. (service fprintd-service-type)
  24341. @end lisp
  24342. @end defvr
  24343. @cindex sysctl
  24344. @subsubheading System Control Service
  24345. The @code{(gnu services sysctl)} provides a service to configure kernel
  24346. parameters at boot.
  24347. @defvr {Scheme Variable} sysctl-service-type
  24348. The service type for @command{sysctl}, which modifies kernel parameters
  24349. under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
  24350. instantiated as:
  24351. @lisp
  24352. (service sysctl-service-type
  24353. (sysctl-configuration
  24354. (settings '(("net.ipv4.ip_forward" . "1")))))
  24355. @end lisp
  24356. Since @code{sysctl-service-type} is used in the default lists of
  24357. services, @code{%base-services} and @code{%desktop-services}, you can
  24358. use @code{modify-services} to change its configuration and add the
  24359. kernel parameters that you want (@pxref{Service Reference,
  24360. @code{modify-services}}).
  24361. @lisp
  24362. (modify-services %base-services
  24363. (sysctl-service-type config =>
  24364. (sysctl-configuration
  24365. (settings (append '(("net.ipv4.ip_forward" . "1"))
  24366. %default-sysctl-settings)))))
  24367. @end lisp
  24368. @end defvr
  24369. @deftp {Data Type} sysctl-configuration
  24370. The data type representing the configuration of @command{sysctl}.
  24371. @table @asis
  24372. @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
  24373. The @command{sysctl} executable to use.
  24374. @item @code{settings} (default: @code{%default-sysctl-settings})
  24375. An association list specifies kernel parameters and their values.
  24376. @end table
  24377. @end deftp
  24378. @defvr {Scheme Variable} %default-sysctl-settings
  24379. An association list specifying the default @command{sysctl} parameters
  24380. on Guix System.
  24381. @end defvr
  24382. @cindex pcscd
  24383. @subsubheading PC/SC Smart Card Daemon Service
  24384. The @code{(gnu services security-token)} module provides the following service
  24385. to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
  24386. daemon program for pcsc-lite and the MuscleCard framework. It is a resource
  24387. manager that coordinates communications with smart card readers, smart cards
  24388. and cryptographic tokens that are connected to the system.
  24389. @defvr {Scheme Variable} pcscd-service-type
  24390. Service type for the @command{pcscd} service. Its value must be a
  24391. @code{pcscd-configuration} object. To run pcscd in the default
  24392. configuration, instantiate it as:
  24393. @lisp
  24394. (service pcscd-service-type)
  24395. @end lisp
  24396. @end defvr
  24397. @deftp {Data Type} pcscd-configuration
  24398. The data type representing the configuration of @command{pcscd}.
  24399. @table @asis
  24400. @item @code{pcsc-lite} (default: @code{pcsc-lite})
  24401. The pcsc-lite package that provides pcscd.
  24402. @item @code{usb-drivers} (default: @code{(list ccid)})
  24403. List of packages that provide USB drivers to pcscd. Drivers are expected to be
  24404. under @file{pcsc/drivers} in the store directory of the package.
  24405. @end table
  24406. @end deftp
  24407. @cindex lirc
  24408. @subsubheading Lirc Service
  24409. The @code{(gnu services lirc)} module provides the following service.
  24410. @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
  24411. [#:device #f] [#:driver #f] [#:config-file #f] @
  24412. [#:extra-options '()]
  24413. Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
  24414. decodes infrared signals from remote controls.
  24415. Optionally, @var{device}, @var{driver} and @var{config-file}
  24416. (configuration file name) may be specified. See @command{lircd} manual
  24417. for details.
  24418. Finally, @var{extra-options} is a list of additional command-line options
  24419. passed to @command{lircd}.
  24420. @end deffn
  24421. @cindex spice
  24422. @subsubheading Spice Service
  24423. The @code{(gnu services spice)} module provides the following service.
  24424. @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
  24425. Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
  24426. that enables sharing the clipboard with a vm and setting the guest display
  24427. resolution when the graphical console window resizes.
  24428. @end deffn
  24429. @cindex inputattach
  24430. @subsubheading inputattach Service
  24431. @cindex tablet input, for Xorg
  24432. @cindex touchscreen input, for Xorg
  24433. The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
  24434. use input devices such as Wacom tablets, touchscreens, or joysticks with the
  24435. Xorg display server.
  24436. @deffn {Scheme Variable} inputattach-service-type
  24437. Type of a service that runs @command{inputattach} on a device and
  24438. dispatches events from it.
  24439. @end deffn
  24440. @deftp {Data Type} inputattach-configuration
  24441. @table @asis
  24442. @item @code{device-type} (default: @code{"wacom"})
  24443. The type of device to connect to. Run @command{inputattach --help}, from the
  24444. @code{inputattach} package, to see the list of supported device types.
  24445. @item @code{device} (default: @code{"/dev/ttyS0"})
  24446. The device file to connect to the device.
  24447. @item @code{baud-rate} (default: @code{#f})
  24448. Baud rate to use for the serial connection.
  24449. Should be a number or @code{#f}.
  24450. @item @code{log-file} (default: @code{#f})
  24451. If true, this must be the name of a file to log messages to.
  24452. @end table
  24453. @end deftp
  24454. @subsubheading Dictionary Service
  24455. @cindex dictionary
  24456. The @code{(gnu services dict)} module provides the following service:
  24457. @defvr {Scheme Variable} dicod-service-type
  24458. This is the type of the service that runs the @command{dicod} daemon, an
  24459. implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
  24460. @end defvr
  24461. @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
  24462. Return a service that runs the @command{dicod} daemon, an implementation
  24463. of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
  24464. The optional @var{config} argument specifies the configuration for
  24465. @command{dicod}, which should be a @code{<dicod-configuration>} object, by
  24466. default it serves the GNU Collaborative International Dictionary of English.
  24467. You can add @command{open localhost} to your @file{~/.dico} file to make
  24468. @code{localhost} the default server for @command{dico} client
  24469. (@pxref{Initialization File,,, dico, GNU Dico Manual}).
  24470. @end deffn
  24471. @deftp {Data Type} dicod-configuration
  24472. Data type representing the configuration of dicod.
  24473. @table @asis
  24474. @item @code{dico} (default: @var{dico})
  24475. Package object of the GNU Dico dictionary server.
  24476. @item @code{interfaces} (default: @var{'("localhost")})
  24477. This is the list of IP addresses and ports and possibly socket file
  24478. names to listen to (@pxref{Server Settings, @code{listen} directive,,
  24479. dico, GNU Dico Manual}).
  24480. @item @code{handlers} (default: @var{'()})
  24481. List of @code{<dicod-handler>} objects denoting handlers (module instances).
  24482. @item @code{databases} (default: @var{(list %dicod-database:gcide)})
  24483. List of @code{<dicod-database>} objects denoting dictionaries to be served.
  24484. @end table
  24485. @end deftp
  24486. @deftp {Data Type} dicod-handler
  24487. Data type representing a dictionary handler (module instance).
  24488. @table @asis
  24489. @item @code{name}
  24490. Name of the handler (module instance).
  24491. @item @code{module} (default: @var{#f})
  24492. Name of the dicod module of the handler (instance). If it is @code{#f},
  24493. the module has the same name as the handler.
  24494. (@pxref{Modules,,, dico, GNU Dico Manual}).
  24495. @item @code{options}
  24496. List of strings or gexps representing the arguments for the module handler
  24497. @end table
  24498. @end deftp
  24499. @deftp {Data Type} dicod-database
  24500. Data type representing a dictionary database.
  24501. @table @asis
  24502. @item @code{name}
  24503. Name of the database, will be used in DICT commands.
  24504. @item @code{handler}
  24505. Name of the dicod handler (module instance) used by this database
  24506. (@pxref{Handlers,,, dico, GNU Dico Manual}).
  24507. @item @code{complex?} (default: @var{#f})
  24508. Whether the database configuration complex. The complex configuration
  24509. will need a corresponding @code{<dicod-handler>} object, otherwise not.
  24510. @item @code{options}
  24511. List of strings or gexps representing the arguments for the database
  24512. (@pxref{Databases,,, dico, GNU Dico Manual}).
  24513. @end table
  24514. @end deftp
  24515. @defvr {Scheme Variable} %dicod-database:gcide
  24516. A @code{<dicod-database>} object serving the GNU Collaborative International
  24517. Dictionary of English using the @code{gcide} package.
  24518. @end defvr
  24519. The following is an example @code{dicod-service} configuration.
  24520. @lisp
  24521. (dicod-service #:config
  24522. (dicod-configuration
  24523. (handlers (list (dicod-handler
  24524. (name "wordnet")
  24525. (module "dictorg")
  24526. (options
  24527. (list #~(string-append "dbdir=" #$wordnet))))))
  24528. (databases (list (dicod-database
  24529. (name "wordnet")
  24530. (complex? #t)
  24531. (handler "wordnet")
  24532. (options '("database=wn")))
  24533. %dicod-database:gcide))))
  24534. @end lisp
  24535. @cindex Docker
  24536. @subsubheading Docker Service
  24537. The @code{(gnu services docker)} module provides the following services.
  24538. @defvr {Scheme Variable} docker-service-type
  24539. This is the type of the service that runs @url{https://www.docker.com,Docker},
  24540. a daemon that can execute application bundles (sometimes referred to as
  24541. ``containers'') in isolated environments.
  24542. @end defvr
  24543. @deftp {Data Type} docker-configuration
  24544. This is the data type representing the configuration of Docker and Containerd.
  24545. @table @asis
  24546. @item @code{package} (default: @code{docker})
  24547. The Docker daemon package to use.
  24548. @item @code{package} (default: @code{docker-cli})
  24549. The Docker client package to use.
  24550. @item @code{containerd} (default: @var{containerd})
  24551. The Containerd package to use.
  24552. @item @code{proxy} (default @var{docker-libnetwork-cmd-proxy})
  24553. The Docker user-land networking proxy package to use.
  24554. @item @code{enable-proxy?} (default @code{#t})
  24555. Enable or disable the use of the Docker user-land networking proxy.
  24556. @item @code{debug?} (default @code{#f})
  24557. Enable or disable debug output.
  24558. @item @code{enable-iptables?} (default @code{#t})
  24559. Enable or disable the addition of iptables rules.
  24560. @end table
  24561. @end deftp
  24562. @cindex Singularity, container service
  24563. @defvr {Scheme Variable} singularity-service-type
  24564. This is the type of the service that allows you to run
  24565. @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
  24566. create and run application bundles (aka. ``containers''). The value for this
  24567. service is the Singularity package to use.
  24568. The service does not install a daemon; instead, it installs helper programs as
  24569. setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
  24570. @command{singularity run} and similar commands.
  24571. @end defvr
  24572. @cindex Audit
  24573. @subsubheading Auditd Service
  24574. The @code{(gnu services auditd)} module provides the following service.
  24575. @defvr {Scheme Variable} auditd-service-type
  24576. This is the type of the service that runs
  24577. @url{https://people.redhat.com/sgrubb/audit/,auditd},
  24578. a daemon that tracks security-relevant information on your system.
  24579. Examples of things that can be tracked:
  24580. @enumerate
  24581. @item
  24582. File accesses
  24583. @item
  24584. System calls
  24585. @item
  24586. Invoked commands
  24587. @item
  24588. Failed login attempts
  24589. @item
  24590. Firewall filtering
  24591. @item
  24592. Network access
  24593. @end enumerate
  24594. @command{auditctl} from the @code{audit} package can be used in order
  24595. to add or remove events to be tracked (until the next reboot).
  24596. In order to permanently track events, put the command line arguments
  24597. of auditctl into a file called @code{audit.rules} in the configuration
  24598. directory (see below).
  24599. @command{aureport} from the @code{audit} package can be used in order
  24600. to view a report of all recorded events.
  24601. The audit daemon by default logs into the file
  24602. @file{/var/log/audit.log}.
  24603. @end defvr
  24604. @deftp {Data Type} auditd-configuration
  24605. This is the data type representing the configuration of auditd.
  24606. @table @asis
  24607. @item @code{audit} (default: @code{audit})
  24608. The audit package to use.
  24609. @item @code{configuration-directory} (default: @code{%default-auditd-configuration-directory})
  24610. The directory containing the configuration file for the audit package, which
  24611. must be named @code{auditd.conf}, and optionally some audit rules to
  24612. instantiate on startup.
  24613. @end table
  24614. @end deftp
  24615. @cindex rshiny
  24616. @subsubheading R-Shiny service
  24617. The @code{(gnu services science)} module provides the following service.
  24618. @defvr {Scheme Variable} rshiny-service-type
  24619. This is a type of service which is used to run a webapp created with
  24620. @code{r-shiny}. This service sets the @env{R_LIBS_USER} environment
  24621. variable and runs the provided script to call @code{runApp}.
  24622. @deftp {Data Type} rshiny-configuration
  24623. This is the data type representing the configuration of rshiny.
  24624. @table @asis
  24625. @item @code{package} (default: @code{r-shiny})
  24626. The package to use.
  24627. @item @code{binary} (defaunlt @code{"rshiny"})
  24628. The name of the binary or shell script located at @code{package/bin/} to
  24629. run when the service is run.
  24630. The common way to create this file is as follows:
  24631. @lisp
  24632. @dots{}
  24633. (let* ((out (assoc-ref %outputs "out"))
  24634. (targetdir (string-append out "/share/" ,name))
  24635. (app (string-append out "/bin/" ,name))
  24636. (Rbin (string-append (assoc-ref %build-inputs "r-min")
  24637. "/bin/Rscript")))
  24638. ;; @dots{}
  24639. (mkdir-p (string-append out "/bin"))
  24640. (call-with-output-file app
  24641. (lambda (port)
  24642. (format port
  24643. "#!~a
  24644. library(shiny)
  24645. setwd(\"~a\")
  24646. runApp(launch.browser=0, port=4202)~%\n"
  24647. Rbin targetdir))))
  24648. @end lisp
  24649. @end table
  24650. @end deftp
  24651. @end defvr
  24652. @cindex Nix
  24653. @subsubheading Nix service
  24654. The @code{(gnu services nix)} module provides the following service.
  24655. @defvr {Scheme Variable} nix-service-type
  24656. This is the type of the service that runs build daemon of the
  24657. @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
  24658. how to use it:
  24659. @lisp
  24660. (use-modules (gnu))
  24661. (use-service-modules nix)
  24662. (use-package-modules package-management)
  24663. (operating-system
  24664. ;; @dots{}
  24665. (packages (append (list nix)
  24666. %base-packages))
  24667. (services (append (list (service nix-service-type))
  24668. %base-services)))
  24669. @end lisp
  24670. After @command{guix system reconfigure} configure Nix for your user:
  24671. @itemize
  24672. @item Add a Nix channel and update it. See
  24673. @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
  24674. @item Create a symlink to your profile and activate Nix profile:
  24675. @end itemize
  24676. @example
  24677. $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
  24678. $ source /run/current-system/profile/etc/profile.d/nix.sh
  24679. @end example
  24680. @end defvr
  24681. @deftp {Data Type} nix-configuration
  24682. This data type represents the configuration of the Nix daemon.
  24683. @table @asis
  24684. @item @code{nix} (default: @code{nix})
  24685. The Nix package to use.
  24686. @item @code{sandbox} (default: @code{#t})
  24687. Specifies whether builds are sandboxed by default.
  24688. @item @code{build-sandbox-items} (default: @code{'()})
  24689. This is a list of strings or objects appended to the
  24690. @code{build-sandbox-items} field of the configuration file.
  24691. @item @code{extra-config} (default: @code{'()})
  24692. This is a list of strings or objects appended to the configuration file.
  24693. It is used to pass extra text to be added verbatim to the configuration
  24694. file.
  24695. @item @code{extra-options} (default: @code{'()})
  24696. Extra command line options for @code{nix-service-type}.
  24697. @end table
  24698. @end deftp
  24699. @node Setuid Programs
  24700. @section Setuid Programs
  24701. @cindex setuid programs
  24702. Some programs need to run with ``root'' privileges, even when they are
  24703. launched by unprivileged users. A notorious example is the
  24704. @command{passwd} program, which users can run to change their
  24705. password, and which needs to access the @file{/etc/passwd} and
  24706. @file{/etc/shadow} files---something normally restricted to root, for
  24707. obvious security reasons. To address that, these executables are
  24708. @dfn{setuid-root}, meaning that they always run with root privileges
  24709. (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
  24710. for more info about the setuid mechanism).
  24711. The store itself @emph{cannot} contain setuid programs: that would be a
  24712. security issue since any user on the system can write derivations that
  24713. populate the store (@pxref{The Store}). Thus, a different mechanism is
  24714. used: instead of changing the setuid bit directly on files that are in
  24715. the store, we let the system administrator @emph{declare} which programs
  24716. should be setuid root.
  24717. The @code{setuid-programs} field of an @code{operating-system}
  24718. declaration contains a list of G-expressions denoting the names of
  24719. programs to be setuid-root (@pxref{Using the Configuration System}).
  24720. For instance, the @command{passwd} program, which is part of the Shadow
  24721. package, can be designated by this G-expression (@pxref{G-Expressions}):
  24722. @example
  24723. #~(string-append #$shadow "/bin/passwd")
  24724. @end example
  24725. A default set of setuid programs is defined by the
  24726. @code{%setuid-programs} variable of the @code{(gnu system)} module.
  24727. @defvr {Scheme Variable} %setuid-programs
  24728. A list of G-expressions denoting common programs that are setuid-root.
  24729. The list includes commands such as @command{passwd}, @command{ping},
  24730. @command{su}, and @command{sudo}.
  24731. @end defvr
  24732. Under the hood, the actual setuid programs are created in the
  24733. @file{/run/setuid-programs} directory at system activation time. The
  24734. files in this directory refer to the ``real'' binaries, which are in the
  24735. store.
  24736. @node X.509 Certificates
  24737. @section X.509 Certificates
  24738. @cindex HTTPS, certificates
  24739. @cindex X.509 certificates
  24740. @cindex TLS
  24741. Web servers available over HTTPS (that is, HTTP over the transport-layer
  24742. security mechanism, TLS) send client programs an @dfn{X.509 certificate}
  24743. that the client can then use to @emph{authenticate} the server. To do
  24744. that, clients verify that the server's certificate is signed by a
  24745. so-called @dfn{certificate authority} (CA). But to verify the CA's
  24746. signature, clients must have first acquired the CA's certificate.
  24747. Web browsers such as GNU@tie{}IceCat include their own set of CA
  24748. certificates, such that they are able to verify CA signatures
  24749. out-of-the-box.
  24750. However, most other programs that can talk HTTPS---@command{wget},
  24751. @command{git}, @command{w3m}, etc.---need to be told where CA
  24752. certificates can be found.
  24753. @cindex @code{nss-certs}
  24754. In Guix, this is done by adding a package that provides certificates
  24755. to the @code{packages} field of the @code{operating-system} declaration
  24756. (@pxref{operating-system Reference}). Guix includes one such package,
  24757. @code{nss-certs}, which is a set of CA certificates provided as part of
  24758. Mozilla's Network Security Services.
  24759. Note that it is @emph{not} part of @code{%base-packages}, so you need to
  24760. explicitly add it. The @file{/etc/ssl/certs} directory, which is where
  24761. most applications and libraries look for certificates by default, points
  24762. to the certificates installed globally.
  24763. Unprivileged users, including users of Guix on a foreign distro,
  24764. can also install their own certificate package in
  24765. their profile. A number of environment variables need to be defined so
  24766. that applications and libraries know where to find them. Namely, the
  24767. OpenSSL library honors the @env{SSL_CERT_DIR} and @env{SSL_CERT_FILE}
  24768. variables. Some applications add their own environment variables; for
  24769. instance, the Git version control system honors the certificate bundle
  24770. pointed to by the @env{GIT_SSL_CAINFO} environment variable. Thus, you
  24771. would typically run something like:
  24772. @example
  24773. guix install nss-certs
  24774. export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
  24775. export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
  24776. export GIT_SSL_CAINFO="$SSL_CERT_FILE"
  24777. @end example
  24778. As another example, R requires the @env{CURL_CA_BUNDLE} environment
  24779. variable to point to a certificate bundle, so you would have to run
  24780. something like this:
  24781. @example
  24782. guix install nss-certs
  24783. export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
  24784. @end example
  24785. For other applications you may want to look up the required environment
  24786. variable in the relevant documentation.
  24787. @node Name Service Switch
  24788. @section Name Service Switch
  24789. @cindex name service switch
  24790. @cindex NSS
  24791. The @code{(gnu system nss)} module provides bindings to the
  24792. configuration file of the libc @dfn{name service switch} or @dfn{NSS}
  24793. (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
  24794. Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
  24795. extended with new ``name'' lookup methods for system databases, which
  24796. includes host names, service names, user accounts, and more (@pxref{Name
  24797. Service Switch, System Databases and Name Service Switch,, libc, The GNU
  24798. C Library Reference Manual}).
  24799. The NSS configuration specifies, for each system database, which lookup
  24800. method is to be used, and how the various methods are chained
  24801. together---for instance, under which circumstances NSS should try the
  24802. next method in the list. The NSS configuration is given in the
  24803. @code{name-service-switch} field of @code{operating-system} declarations
  24804. (@pxref{operating-system Reference, @code{name-service-switch}}).
  24805. @cindex nss-mdns
  24806. @cindex .local, host name lookup
  24807. As an example, the declaration below configures the NSS to use the
  24808. @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
  24809. back-end}, which supports host name lookups over multicast DNS (mDNS)
  24810. for host names ending in @code{.local}:
  24811. @lisp
  24812. (name-service-switch
  24813. (hosts (list %files ;first, check /etc/hosts
  24814. ;; If the above did not succeed, try
  24815. ;; with 'mdns_minimal'.
  24816. (name-service
  24817. (name "mdns_minimal")
  24818. ;; 'mdns_minimal' is authoritative for
  24819. ;; '.local'. When it returns "not found",
  24820. ;; no need to try the next methods.
  24821. (reaction (lookup-specification
  24822. (not-found => return))))
  24823. ;; Then fall back to DNS.
  24824. (name-service
  24825. (name "dns"))
  24826. ;; Finally, try with the "full" 'mdns'.
  24827. (name-service
  24828. (name "mdns")))))
  24829. @end lisp
  24830. Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
  24831. contains this configuration, so you will not have to type it if all you
  24832. want is to have @code{.local} host lookup working.
  24833. Note that, in this case, in addition to setting the
  24834. @code{name-service-switch} of the @code{operating-system} declaration,
  24835. you also need to use @code{avahi-service-type} (@pxref{Networking Services,
  24836. @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
  24837. (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
  24838. to the name service cache daemon (@pxref{Base Services,
  24839. @code{nscd-service}}).
  24840. For convenience, the following variables provide typical NSS
  24841. configurations.
  24842. @defvr {Scheme Variable} %default-nss
  24843. This is the default name service switch configuration, a
  24844. @code{name-service-switch} object.
  24845. @end defvr
  24846. @defvr {Scheme Variable} %mdns-host-lookup-nss
  24847. This is the name service switch configuration with support for host name
  24848. lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
  24849. @end defvr
  24850. The reference for name service switch configuration is given below. It
  24851. is a direct mapping of the configuration file format of the C library , so
  24852. please refer to the C library manual for more information (@pxref{NSS
  24853. Configuration File,,, libc, The GNU C Library Reference Manual}).
  24854. Compared to the configuration file format of libc NSS, it has the advantage
  24855. not only of adding this warm parenthetic feel that we like, but also
  24856. static checks: you will know about syntax errors and typos as soon as you
  24857. run @command{guix system}.
  24858. @deftp {Data Type} name-service-switch
  24859. This is the data type representation the configuration of libc's name
  24860. service switch (NSS). Each field below represents one of the supported
  24861. system databases.
  24862. @table @code
  24863. @item aliases
  24864. @itemx ethers
  24865. @itemx group
  24866. @itemx gshadow
  24867. @itemx hosts
  24868. @itemx initgroups
  24869. @itemx netgroup
  24870. @itemx networks
  24871. @itemx password
  24872. @itemx public-key
  24873. @itemx rpc
  24874. @itemx services
  24875. @itemx shadow
  24876. The system databases handled by the NSS@. Each of these fields must be a
  24877. list of @code{<name-service>} objects (see below).
  24878. @end table
  24879. @end deftp
  24880. @deftp {Data Type} name-service
  24881. This is the data type representing an actual name service and the
  24882. associated lookup action.
  24883. @table @code
  24884. @item name
  24885. A string denoting the name service (@pxref{Services in the NSS
  24886. configuration,,, libc, The GNU C Library Reference Manual}).
  24887. Note that name services listed here must be visible to nscd. This is
  24888. achieved by passing the @code{#:name-services} argument to
  24889. @code{nscd-service} the list of packages providing the needed name
  24890. services (@pxref{Base Services, @code{nscd-service}}).
  24891. @item reaction
  24892. An action specified using the @code{lookup-specification} macro
  24893. (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
  24894. Reference Manual}). For example:
  24895. @lisp
  24896. (lookup-specification (unavailable => continue)
  24897. (success => return))
  24898. @end lisp
  24899. @end table
  24900. @end deftp
  24901. @node Initial RAM Disk
  24902. @section Initial RAM Disk
  24903. @cindex initrd
  24904. @cindex initial RAM disk
  24905. For bootstrapping purposes, the Linux-Libre kernel is passed an
  24906. @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
  24907. root file system as well as an initialization script. The latter is
  24908. responsible for mounting the real root file system, and for loading any
  24909. kernel modules that may be needed to achieve that.
  24910. The @code{initrd-modules} field of an @code{operating-system}
  24911. declaration allows you to specify Linux-libre kernel modules that must
  24912. be available in the initrd. In particular, this is where you would list
  24913. modules needed to actually drive the hard disk where your root partition
  24914. is---although the default value of @code{initrd-modules} should cover
  24915. most use cases. For example, assuming you need the @code{megaraid_sas}
  24916. module in addition to the default modules to be able to access your root
  24917. file system, you would write:
  24918. @lisp
  24919. (operating-system
  24920. ;; @dots{}
  24921. (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
  24922. @end lisp
  24923. @defvr {Scheme Variable} %base-initrd-modules
  24924. This is the list of kernel modules included in the initrd by default.
  24925. @end defvr
  24926. Furthermore, if you need lower-level customization, the @code{initrd}
  24927. field of an @code{operating-system} declaration allows
  24928. you to specify which initrd you would like to use. The @code{(gnu
  24929. system linux-initrd)} module provides three ways to build an initrd: the
  24930. high-level @code{base-initrd} procedure and the low-level
  24931. @code{raw-initrd} and @code{expression->initrd} procedures.
  24932. The @code{base-initrd} procedure is intended to cover most common uses.
  24933. For example, if you want to add a bunch of kernel modules to be loaded
  24934. at boot time, you can define the @code{initrd} field of the operating
  24935. system declaration like this:
  24936. @lisp
  24937. (initrd (lambda (file-systems . rest)
  24938. ;; Create a standard initrd but set up networking
  24939. ;; with the parameters QEMU expects by default.
  24940. (apply base-initrd file-systems
  24941. #:qemu-networking? #t
  24942. rest)))
  24943. @end lisp
  24944. The @code{base-initrd} procedure also handles common use cases that
  24945. involves using the system as a QEMU guest, or as a ``live'' system with
  24946. volatile root file system.
  24947. The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
  24948. Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
  24949. such as trying to guess which kernel modules and packages should be included
  24950. to the initrd. An example use of @code{raw-initrd} is when a user has
  24951. a custom Linux kernel configuration and default kernel modules included by
  24952. @code{base-initrd} are not available.
  24953. The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
  24954. honors several options passed on the Linux kernel command line
  24955. (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
  24956. @code{-append} option of QEMU), notably:
  24957. @table @code
  24958. @item --load=@var{boot}
  24959. Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
  24960. program, once it has mounted the root file system.
  24961. Guix uses this option to yield control to a boot program that runs the
  24962. service activation programs and then spawns the GNU@tie{}Shepherd, the
  24963. initialization system.
  24964. @item --root=@var{root}
  24965. Mount @var{root} as the root file system. @var{root} can be a device
  24966. name like @code{/dev/sda1}, a file system label, or a file system UUID.
  24967. When unspecified, the device name from the root file system of the
  24968. operating system declaration is used.
  24969. @item --system=@var{system}
  24970. Have @file{/run/booted-system} and @file{/run/current-system} point to
  24971. @var{system}.
  24972. @item modprobe.blacklist=@var{modules}@dots{}
  24973. @cindex module, black-listing
  24974. @cindex black list, of kernel modules
  24975. Instruct the initial RAM disk as well as the @command{modprobe} command
  24976. (from the kmod package) to refuse to load @var{modules}. @var{modules}
  24977. must be a comma-separated list of module names---e.g.,
  24978. @code{usbkbd,9pnet}.
  24979. @item --repl
  24980. Start a read-eval-print loop (REPL) from the initial RAM disk before it
  24981. tries to load kernel modules and to mount the root file system. Our
  24982. marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
  24983. love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
  24984. Manual}, for more information on Guile's REPL.
  24985. @end table
  24986. Now that you know all the features that initial RAM disks produced by
  24987. @code{base-initrd} and @code{raw-initrd} provide,
  24988. here is how to use it and customize it further.
  24989. @cindex initrd
  24990. @cindex initial RAM disk
  24991. @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
  24992. [#:linux-modules '()] [#:mapped-devices '()] @
  24993. [#:keyboard-layout #f] @
  24994. [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
  24995. Return a derivation that builds a raw initrd. @var{file-systems} is
  24996. a list of file systems to be mounted by the initrd, possibly in addition to
  24997. the root file system specified on the kernel command line via @option{--root}.
  24998. @var{linux-modules} is a list of kernel modules to be loaded at boot time.
  24999. @var{mapped-devices} is a list of device mappings to realize before
  25000. @var{file-systems} are mounted (@pxref{Mapped Devices}).
  25001. @var{helper-packages} is a list of packages to be copied in the initrd.
  25002. It may
  25003. include @code{e2fsck/static} or other packages needed by the initrd to check
  25004. the root file system.
  25005. When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
  25006. the desired console keyboard layout. This is done before @var{mapped-devices}
  25007. are set up and before @var{file-systems} are mounted such that, should the
  25008. user need to enter a passphrase or use the REPL, this happens using the
  25009. intended keyboard layout.
  25010. When @var{qemu-networking?} is true, set up networking with the standard QEMU
  25011. parameters. When @var{virtio?} is true, load additional modules so that the
  25012. initrd can be used as a QEMU guest with para-virtualized I/O drivers.
  25013. When @var{volatile-root?} is true, the root file system is writable but any changes
  25014. to it are lost.
  25015. @end deffn
  25016. @deffn {Scheme Procedure} base-initrd @var{file-systems} @
  25017. [#:mapped-devices '()] [#:keyboard-layout #f] @
  25018. [#:qemu-networking? #f] [#:volatile-root? #f] @
  25019. [#:linux-modules '()]
  25020. Return as a file-like object a generic initrd, with kernel
  25021. modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
  25022. mounted by the initrd, possibly in addition to the root file system specified
  25023. on the kernel command line via @option{--root}. @var{mapped-devices} is a list of device
  25024. mappings to realize before @var{file-systems} are mounted.
  25025. When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
  25026. the desired console keyboard layout. This is done before @var{mapped-devices}
  25027. are set up and before @var{file-systems} are mounted such that, should the
  25028. user need to enter a passphrase or use the REPL, this happens using the
  25029. intended keyboard layout.
  25030. @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
  25031. The initrd is automatically populated with all the kernel modules necessary
  25032. for @var{file-systems} and for the given options. Additional kernel
  25033. modules can be listed in @var{linux-modules}. They will be added to the initrd, and
  25034. loaded at boot time in the order in which they appear.
  25035. @end deffn
  25036. Needless to say, the initrds we produce and use embed a
  25037. statically-linked Guile, and the initialization program is a Guile
  25038. program. That gives a lot of flexibility. The
  25039. @code{expression->initrd} procedure builds such an initrd, given the
  25040. program to run in that initrd.
  25041. @deffn {Scheme Procedure} expression->initrd @var{exp} @
  25042. [#:guile %guile-3.0-static-stripped] [#:name "guile-initrd"]
  25043. Return as a file-like object a Linux initrd (a gzipped cpio archive)
  25044. containing @var{guile} and that evaluates @var{exp}, a G-expression,
  25045. upon booting. All the derivations referenced by @var{exp} are
  25046. automatically copied to the initrd.
  25047. @end deffn
  25048. @node Bootloader Configuration
  25049. @section Bootloader Configuration
  25050. @cindex bootloader
  25051. @cindex boot loader
  25052. The operating system supports multiple bootloaders. The bootloader is
  25053. configured using @code{bootloader-configuration} declaration. All the
  25054. fields of this structure are bootloader agnostic except for one field,
  25055. @code{bootloader} that indicates the bootloader to be configured and
  25056. installed.
  25057. Some of the bootloaders do not honor every field of
  25058. @code{bootloader-configuration}. For instance, the extlinux
  25059. bootloader does not support themes and thus ignores the @code{theme}
  25060. field.
  25061. @deftp {Data Type} bootloader-configuration
  25062. The type of a bootloader configuration declaration.
  25063. @table @asis
  25064. @item @code{bootloader}
  25065. @cindex EFI, bootloader
  25066. @cindex UEFI, bootloader
  25067. @cindex BIOS, bootloader
  25068. The bootloader to use, as a @code{bootloader} object. For now
  25069. @code{grub-bootloader}, @code{grub-efi-bootloader},
  25070. @code{grub-efi-netboot-bootloader}, @code{extlinux-bootloader} and
  25071. @code{u-boot-bootloader} are supported.
  25072. @cindex ARM, bootloaders
  25073. @cindex AArch64, bootloaders
  25074. Available bootloaders are described in @code{(gnu bootloader @dots{})}
  25075. modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
  25076. of bootloaders for a wide range of ARM and AArch64 systems, using the
  25077. @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
  25078. @vindex grub-efi-bootloader
  25079. @code{grub-efi-bootloader} allows to boot on modern systems using the
  25080. @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
  25081. use if the installation image contains a @file{/sys/firmware/efi} directory
  25082. when you boot it on your system.
  25083. @vindex grub-bootloader
  25084. @code{grub-bootloader} allows you to boot in particular Intel-based machines
  25085. in ``legacy'' BIOS mode.
  25086. @vindex grub-efi-netboot-bootloader
  25087. @code{grub-efi-netboot-bootloader} allows you to boot your system over network
  25088. through TFTP@. In combination with an NFS root file system this allows you to
  25089. build a diskless Guix system.
  25090. The installation of the @code{grub-efi-netboot-bootloader} generates the content
  25091. of the TFTP root directory at @code{target}
  25092. (@pxref{Bootloader Configuration, @code{target}}), to be served by a TFTP server.
  25093. You may want to mount your TFTP server directory onto @code{target} to move the
  25094. required files to the TFTP server automatically.
  25095. If you plan to use an NFS root file system as well (actually if you mount the
  25096. store from an NFS share), then the TFTP server needs to serve the file
  25097. @file{/boot/grub/grub.cfg} and other files from the store (like GRUBs background
  25098. image, the kernel (@pxref{operating-system Reference, @code{kernel}}) and the
  25099. initrd (@pxref{operating-system Reference, @code{initrd}})), too. All these
  25100. files from the store will be accessed by GRUB through TFTP with their normal
  25101. store path, for example as
  25102. @file{tftp://tftp-server/gnu/store/…-initrd/initrd.cpio.gz}.
  25103. Two symlinks are created to make this possible. The first symlink is
  25104. @code{target}@file{/efi/Guix/boot/grub/grub.cfg} pointing to
  25105. @file{../../../boot/grub/grub.cfg},
  25106. where @code{target} may be @file{/boot}. In this case the link is not leaving
  25107. the served TFTP root directory, but otherwise it does. The second link is
  25108. @code{target}@file{/gnu/store} and points to @file{../gnu/store}. This link
  25109. is leaving the served TFTP root directory.
  25110. The assumption behind all this is that you have an NFS server exporting the root
  25111. file system for your Guix system, and additionally a TFTP server exporting your
  25112. @code{target} directory—usually @file{/boot}—from that same root file system for
  25113. your Guix system. In this constellation the symlinks will work.
  25114. For other constellations you will have to program your own bootloader installer,
  25115. which then takes care to make necessary files from the store accessible through
  25116. TFTP, for example by copying them into the TFTP root directory at @code{target}.
  25117. It is important to note that symlinks pointing outside the TFTP root directory
  25118. may need to be allowed in the configuration of your TFTP server. Further the
  25119. store link exposes the whole store through TFTP@. Both points need to be
  25120. considered carefully for security aspects.
  25121. Beside the @code{grub-efi-netboot-bootloader}, the already mentioned TFTP and
  25122. NFS servers, you also need a properly configured DHCP server to make the booting
  25123. over netboot possible. For all this we can currently only recommend you to look
  25124. for instructions about @acronym{PXE, Preboot eXecution Environment}.
  25125. @item @code{target}
  25126. This is a string denoting the target onto which to install the
  25127. bootloader.
  25128. The interpretation depends on the bootloader in question. For
  25129. @code{grub-bootloader}, for example, it should be a device name understood by
  25130. the bootloader @command{installer} command, such as @code{/dev/sda} or
  25131. @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
  25132. @code{grub-efi-bootloader}, it should be the mount point of the EFI file
  25133. system, usually @file{/boot/efi}. For @code{grub-efi-netboot-bootloader},
  25134. @code{target} should be the mount point corresponding to the TFTP root
  25135. directory of your TFTP server.
  25136. @item @code{menu-entries} (default: @code{()})
  25137. A possibly empty list of @code{menu-entry} objects (see below), denoting
  25138. entries to appear in the bootloader menu, in addition to the current
  25139. system entry and the entry pointing to previous system generations.
  25140. @item @code{default-entry} (default: @code{0})
  25141. The index of the default boot menu entry. Index 0 is for the entry of the
  25142. current system.
  25143. @item @code{timeout} (default: @code{5})
  25144. The number of seconds to wait for keyboard input before booting. Set to
  25145. 0 to boot immediately, and to -1 to wait indefinitely.
  25146. @cindex keyboard layout, for the bootloader
  25147. @item @code{keyboard-layout} (default: @code{#f})
  25148. If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
  25149. layout, usually US@tie{}English (``qwerty'').
  25150. Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
  25151. Layout}).
  25152. @quotation Note
  25153. This option is currently ignored by bootloaders other than @code{grub} and
  25154. @code{grub-efi}.
  25155. @end quotation
  25156. @item @code{theme} (default: @var{#f})
  25157. The bootloader theme object describing the theme to use. If no theme
  25158. is provided, some bootloaders might use a default theme, that's true
  25159. for GRUB.
  25160. @item @code{terminal-outputs} (default: @code{'(gfxterm)})
  25161. The output terminals used for the bootloader boot menu, as a list of
  25162. symbols. GRUB accepts the values: @code{console}, @code{serial},
  25163. @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
  25164. @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
  25165. corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
  25166. configuration,,, grub,GNU GRUB manual}).
  25167. @item @code{terminal-inputs} (default: @code{'()})
  25168. The input terminals used for the bootloader boot menu, as a list of
  25169. symbols. For GRUB, the default is the native platform terminal as
  25170. determined at run-time. GRUB accepts the values: @code{console},
  25171. @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
  25172. @code{usb_keyboard}. This field corresponds to the GRUB variable
  25173. @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
  25174. manual}).
  25175. @item @code{serial-unit} (default: @code{#f})
  25176. The serial unit used by the bootloader, as an integer from 0 to 3.
  25177. For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
  25178. corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
  25179. @item @code{serial-speed} (default: @code{#f})
  25180. The speed of the serial interface, as an integer. For GRUB, the
  25181. default value is chosen at run-time; currently GRUB chooses
  25182. 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
  25183. @end table
  25184. @end deftp
  25185. @cindex dual boot
  25186. @cindex boot menu
  25187. Should you want to list additional boot menu entries @i{via} the
  25188. @code{menu-entries} field above, you will need to create them with the
  25189. @code{menu-entry} form. For example, imagine you want to be able to
  25190. boot another distro (hard to imagine!), you can define a menu entry
  25191. along these lines:
  25192. @lisp
  25193. (menu-entry
  25194. (label "The Other Distro")
  25195. (linux "/boot/old/vmlinux-2.6.32")
  25196. (linux-arguments '("root=/dev/sda2"))
  25197. (initrd "/boot/old/initrd"))
  25198. @end lisp
  25199. Details below.
  25200. @deftp {Data Type} menu-entry
  25201. The type of an entry in the bootloader menu.
  25202. @table @asis
  25203. @item @code{label}
  25204. The label to show in the menu---e.g., @code{"GNU"}.
  25205. @item @code{linux} (default: @code{#f})
  25206. The Linux kernel image to boot, for example:
  25207. @lisp
  25208. (file-append linux-libre "/bzImage")
  25209. @end lisp
  25210. For GRUB, it is also possible to specify a device explicitly in the
  25211. file path using GRUB's device naming convention (@pxref{Naming
  25212. convention,,, grub, GNU GRUB manual}), for example:
  25213. @example
  25214. "(hd0,msdos1)/boot/vmlinuz"
  25215. @end example
  25216. If the device is specified explicitly as above, then the @code{device}
  25217. field is ignored entirely.
  25218. @item @code{linux-arguments} (default: @code{()})
  25219. The list of extra Linux kernel command-line arguments---e.g.,
  25220. @code{("console=ttyS0")}.
  25221. @item @code{initrd} (default: @code{#f})
  25222. A G-Expression or string denoting the file name of the initial RAM disk
  25223. to use (@pxref{G-Expressions}).
  25224. @item @code{device} (default: @code{#f})
  25225. The device where the kernel and initrd are to be found---i.e., for GRUB,
  25226. @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
  25227. This may be a file system label (a string), a file system UUID (a
  25228. bytevector, @pxref{File Systems}), or @code{#f}, in which case
  25229. the bootloader will search the device containing the file specified by
  25230. the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
  25231. must @emph{not} be an OS device name such as @file{/dev/sda1}.
  25232. @item @code{multiboot-kernel} (default: @code{#f})
  25233. The kernel to boot in Multiboot-mode (@pxref{multiboot,,, grub, GNU GRUB
  25234. manual}). When this field is set, a Multiboot menu-entry is generated.
  25235. For example:
  25236. @lisp
  25237. (file-append mach "/boot/gnumach")
  25238. @end lisp
  25239. @item @code{multiboot-arguments} (default: @code{()})
  25240. The list of extra command-line arguments for the multiboot-kernel.
  25241. @item @code{multiboot-modules} (default: @code{()})
  25242. The list of commands for loading Multiboot modules. For example:
  25243. @lisp
  25244. (list (list (file-append hurd "/hurd/ext2fs.static") "ext2fs"
  25245. @dots{})
  25246. (list (file-append libc "/lib/ld.so.1") "exec"
  25247. @dots{}))
  25248. @end lisp
  25249. @end table
  25250. @end deftp
  25251. @cindex HDPI
  25252. @cindex HiDPI
  25253. @cindex resolution
  25254. @c FIXME: Write documentation once it's stable.
  25255. For now only GRUB has theme support. GRUB themes are created using
  25256. the @code{grub-theme} form, which is not fully documented yet.
  25257. @deftp {Data Type} grub-theme
  25258. Data type representing the configuration of the GRUB theme.
  25259. @table @asis
  25260. @item @code{gfxmode} (default: @code{'("auto")})
  25261. The GRUB @code{gfxmode} to set (a list of screen resolution strings,
  25262. @pxref{gfxmode,,, grub, GNU GRUB manual}).
  25263. @end table
  25264. @end deftp
  25265. @deffn {Scheme Procedure} grub-theme
  25266. Return the default GRUB theme used by the operating system if no
  25267. @code{theme} field is specified in @code{bootloader-configuration}
  25268. record.
  25269. It comes with a fancy background image displaying the GNU and Guix
  25270. logos.
  25271. @end deffn
  25272. For example, to override the default resolution, you may use something
  25273. like
  25274. @lisp
  25275. (bootloader
  25276. (bootloader-configuration
  25277. ;; @dots{}
  25278. (theme (grub-theme
  25279. (inherit (grub-theme))
  25280. (gfxmode '("1024x786x32" "auto"))))))
  25281. @end lisp
  25282. @node Invoking guix system
  25283. @section Invoking @code{guix system}
  25284. Once you have written an operating system declaration as seen in the
  25285. previous section, it can be @dfn{instantiated} using the @command{guix
  25286. system} command. The synopsis is:
  25287. @example
  25288. guix system @var{options}@dots{} @var{action} @var{file}
  25289. @end example
  25290. @var{file} must be the name of a file containing an
  25291. @code{operating-system} declaration. @var{action} specifies how the
  25292. operating system is instantiated. Currently the following values are
  25293. supported:
  25294. @table @code
  25295. @item search
  25296. Display available service type definitions that match the given regular
  25297. expressions, sorted by relevance:
  25298. @cindex HDPI
  25299. @cindex HiDPI
  25300. @cindex resolution
  25301. @example
  25302. $ guix system search console
  25303. name: console-fonts
  25304. location: gnu/services/base.scm:806:2
  25305. extends: shepherd-root
  25306. description: Install the given fonts on the specified ttys (fonts are per
  25307. + virtual console on GNU/Linux). The value of this service is a list of
  25308. + tty/font pairs. The font can be the name of a font provided by the `kbd'
  25309. + package or any valid argument to `setfont', as in this example:
  25310. +
  25311. + '(("tty1" . "LatGrkCyr-8x16")
  25312. + ("tty2" . (file-append
  25313. + font-tamzen
  25314. + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
  25315. + ("tty3" . (file-append
  25316. + font-terminus
  25317. + "/share/consolefonts/ter-132n"))) ; for HDPI
  25318. relevance: 9
  25319. name: mingetty
  25320. location: gnu/services/base.scm:1190:2
  25321. extends: shepherd-root
  25322. description: Provide console login using the `mingetty' program.
  25323. relevance: 2
  25324. name: login
  25325. location: gnu/services/base.scm:860:2
  25326. extends: pam
  25327. description: Provide a console log-in service as specified by its
  25328. + configuration value, a `login-configuration' object.
  25329. relevance: 2
  25330. @dots{}
  25331. @end example
  25332. As for @command{guix package --search}, the result is written in
  25333. @code{recutils} format, which makes it easy to filter the output
  25334. (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
  25335. @item reconfigure
  25336. Build the operating system described in @var{file}, activate it, and
  25337. switch to it@footnote{This action (and the related actions
  25338. @code{switch-generation} and @code{roll-back}) are usable only on
  25339. systems already running Guix System.}.
  25340. @quotation Note
  25341. @c The paragraph below refers to the problem discussed at
  25342. @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
  25343. It is highly recommended to run @command{guix pull} once before you run
  25344. @command{guix system reconfigure} for the first time (@pxref{Invoking
  25345. guix pull}). Failing to do that you would see an older version of Guix
  25346. once @command{reconfigure} has completed.
  25347. @end quotation
  25348. This effects all the configuration specified in @var{file}: user
  25349. accounts, system services, global package list, setuid programs, etc.
  25350. The command starts system services specified in @var{file} that are not
  25351. currently running; if a service is currently running this command will
  25352. arrange for it to be upgraded the next time it is stopped (e.g.@: by
  25353. @code{herd stop X} or @code{herd restart X}).
  25354. This command creates a new generation whose number is one greater than
  25355. the current generation (as reported by @command{guix system
  25356. list-generations}). If that generation already exists, it will be
  25357. overwritten. This behavior mirrors that of @command{guix package}
  25358. (@pxref{Invoking guix package}).
  25359. It also adds a bootloader menu entry for the new OS configuration,
  25360. ---unless @option{--no-bootloader} is passed. For GRUB, it moves
  25361. entries for older configurations to a submenu, allowing you to choose
  25362. an older system generation at boot time should you need it.
  25363. @cindex provenance tracking, of the operating system
  25364. Upon completion, the new system is deployed under
  25365. @file{/run/current-system}. This directory contains @dfn{provenance
  25366. meta-data}: the list of channels in use (@pxref{Channels}) and
  25367. @var{file} itself, when available. You can view it by running:
  25368. @example
  25369. guix system describe
  25370. @end example
  25371. This information is useful should you later want to inspect how this
  25372. particular generation was built. In fact, assuming @var{file} is
  25373. self-contained, you can later rebuild generation @var{n} of your
  25374. operating system with:
  25375. @example
  25376. guix time-machine \
  25377. -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
  25378. system reconfigure \
  25379. /var/guix/profiles/system-@var{n}-link/configuration.scm
  25380. @end example
  25381. You can think of it as some sort of built-in version control! Your
  25382. system is not just a binary artifact: @emph{it carries its own source}.
  25383. @xref{Service Reference, @code{provenance-service-type}}, for more
  25384. information on provenance tracking.
  25385. By default, @command{reconfigure} @emph{prevents you from downgrading
  25386. your system}, which could (re)introduce security vulnerabilities and
  25387. also cause problems with ``stateful'' services such as database
  25388. management systems. You can override that behavior by passing
  25389. @option{--allow-downgrades}.
  25390. @item switch-generation
  25391. @cindex generations
  25392. Switch to an existing system generation. This action atomically
  25393. switches the system profile to the specified system generation. It
  25394. also rearranges the system's existing bootloader menu entries. It
  25395. makes the menu entry for the specified system generation the default,
  25396. and it moves the entries for the other generations to a submenu, if
  25397. supported by the bootloader being used. The next time the system
  25398. boots, it will use the specified system generation.
  25399. The bootloader itself is not being reinstalled when using this
  25400. command. Thus, the installed bootloader is used with an updated
  25401. configuration file.
  25402. The target generation can be specified explicitly by its generation
  25403. number. For example, the following invocation would switch to system
  25404. generation 7:
  25405. @example
  25406. guix system switch-generation 7
  25407. @end example
  25408. The target generation can also be specified relative to the current
  25409. generation with the form @code{+N} or @code{-N}, where @code{+3} means
  25410. ``3 generations ahead of the current generation,'' and @code{-1} means
  25411. ``1 generation prior to the current generation.'' When specifying a
  25412. negative value such as @code{-1}, you must precede it with @code{--} to
  25413. prevent it from being parsed as an option. For example:
  25414. @example
  25415. guix system switch-generation -- -1
  25416. @end example
  25417. Currently, the effect of invoking this action is @emph{only} to switch
  25418. the system profile to an existing generation and rearrange the
  25419. bootloader menu entries. To actually start using the target system
  25420. generation, you must reboot after running this action. In the future,
  25421. it will be updated to do the same things as @command{reconfigure},
  25422. like activating and deactivating services.
  25423. This action will fail if the specified generation does not exist.
  25424. @item roll-back
  25425. @cindex rolling back
  25426. Switch to the preceding system generation. The next time the system
  25427. boots, it will use the preceding system generation. This is the inverse
  25428. of @command{reconfigure}, and it is exactly the same as invoking
  25429. @command{switch-generation} with an argument of @code{-1}.
  25430. Currently, as with @command{switch-generation}, you must reboot after
  25431. running this action to actually start using the preceding system
  25432. generation.
  25433. @item delete-generations
  25434. @cindex deleting system generations
  25435. @cindex saving space
  25436. Delete system generations, making them candidates for garbage collection
  25437. (@pxref{Invoking guix gc}, for information on how to run the ``garbage
  25438. collector'').
  25439. This works in the same way as @samp{guix package --delete-generations}
  25440. (@pxref{Invoking guix package, @option{--delete-generations}}). With no
  25441. arguments, all system generations but the current one are deleted:
  25442. @example
  25443. guix system delete-generations
  25444. @end example
  25445. You can also select the generations you want to delete. The example below
  25446. deletes all the system generations that are more than two month old:
  25447. @example
  25448. guix system delete-generations 2m
  25449. @end example
  25450. Running this command automatically reinstalls the bootloader with an updated
  25451. list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
  25452. longer lists the generations that have been deleted.
  25453. @item build
  25454. Build the derivation of the operating system, which includes all the
  25455. configuration files and programs needed to boot and run the system.
  25456. This action does not actually install anything.
  25457. @item init
  25458. Populate the given directory with all the files necessary to run the
  25459. operating system specified in @var{file}. This is useful for first-time
  25460. installations of Guix System. For instance:
  25461. @example
  25462. guix system init my-os-config.scm /mnt
  25463. @end example
  25464. copies to @file{/mnt} all the store items required by the configuration
  25465. specified in @file{my-os-config.scm}. This includes configuration
  25466. files, packages, and so on. It also creates other essential files
  25467. needed for the system to operate correctly---e.g., the @file{/etc},
  25468. @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
  25469. This command also installs bootloader on the target specified in
  25470. @file{my-os-config}, unless the @option{--no-bootloader} option was
  25471. passed.
  25472. @item vm
  25473. @cindex virtual machine
  25474. @cindex VM
  25475. @anchor{guix system vm}
  25476. Build a virtual machine that contains the operating system declared in
  25477. @var{file}, and return a script to run that virtual machine (VM).
  25478. @quotation Note
  25479. The @code{vm} action and others below
  25480. can use KVM support in the Linux-libre kernel. Specifically, if the
  25481. machine has hardware virtualization support, the corresponding
  25482. KVM kernel module should be loaded, and the @file{/dev/kvm} device node
  25483. must exist and be readable and writable by the user and by the
  25484. build users of the daemon (@pxref{Build Environment Setup}).
  25485. @end quotation
  25486. Arguments given to the script are passed to QEMU as in the example
  25487. below, which enables networking and requests 1@tie{}GiB of RAM for the
  25488. emulated machine:
  25489. @example
  25490. $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -net user,model=virtio-net-pci
  25491. @end example
  25492. The VM shares its store with the host system.
  25493. Additional file systems can be shared between the host and the VM using
  25494. the @option{--share} and @option{--expose} command-line options: the former
  25495. specifies a directory to be shared with write access, while the latter
  25496. provides read-only access to the shared directory.
  25497. The example below creates a VM in which the user's home directory is
  25498. accessible read-only, and where the @file{/exchange} directory is a
  25499. read-write mapping of @file{$HOME/tmp} on the host:
  25500. @example
  25501. guix system vm my-config.scm \
  25502. --expose=$HOME --share=$HOME/tmp=/exchange
  25503. @end example
  25504. On GNU/Linux, the default is to boot directly to the kernel; this has
  25505. the advantage of requiring only a very tiny root disk image since the
  25506. store of the host can then be mounted.
  25507. The @option{--full-boot} option forces a complete boot sequence, starting
  25508. with the bootloader. This requires more disk space since a root image
  25509. containing at least the kernel, initrd, and bootloader data files must
  25510. be created. The @option{--image-size} option can be used to specify the
  25511. size of the image.
  25512. @cindex System images, creation in various formats
  25513. @cindex Creating system images in various formats
  25514. @item image
  25515. @itemx docker-image
  25516. Return a virtual machine, disk image, or Docker image of the operating
  25517. system declared in @var{file} that stands alone. By default,
  25518. @command{guix system} estimates the size of the image needed to store
  25519. the system, but you can use the @option{--image-size} option to specify
  25520. a value. Docker images are built to contain exactly what they need, so
  25521. the @option{--image-size} option is ignored in the case of
  25522. @code{docker-image}.
  25523. @cindex image, creating disk images
  25524. The @code{image} command can produce various image types. The
  25525. image type can be selected using the @option{--image-type} option. It
  25526. defaults to @code{efi-raw}. When its value is @code{iso9660}, the
  25527. @option{--label} option can be used to specify a volume ID with
  25528. @code{image}. By default, the root file system of a disk image is
  25529. mounted non-volatile; the @option{--volatile} option can be provided to
  25530. make it volatile instead. When using @code{image}, the bootloader
  25531. installed on the generated image is taken from the provided
  25532. @code{operating-system} definition. The following example demonstrates
  25533. how to generate an image that uses the @code{grub-efi-bootloader}
  25534. bootloader and boot it with QEMU:
  25535. @example
  25536. image=$(guix system image --image-type=qcow2 \
  25537. gnu/system/examples/lightweight-desktop.tmpl)
  25538. cp $image /tmp/my-image.qcow2
  25539. chmod +w /tmp/my-image.qcow2
  25540. qemu-system-x86_64 -enable-kvm -hda /tmp/my-image.qcow2 -m 1000 \
  25541. -bios $(guix build ovmf)/share/firmware/ovmf_x64.bin
  25542. @end example
  25543. When using the @code{efi-raw} image type, a raw disk image is produced;
  25544. it can be copied as is to a USB stick, for instance. Assuming
  25545. @code{/dev/sdc} is the device corresponding to a USB stick, one can copy
  25546. the image to it using the following command:
  25547. @example
  25548. # dd if=$(guix system image my-os.scm) of=/dev/sdc status=progress
  25549. @end example
  25550. The @code{--list-image-types} command lists all the available image
  25551. types.
  25552. @cindex creating virtual machine images
  25553. When using the @code{qcow2} image type, the returned image is in qcow2
  25554. format, which the QEMU emulator can efficiently use. @xref{Running Guix
  25555. in a VM}, for more information on how to run the image in a virtual
  25556. machine. The @code{grub-bootloader} bootloader is always used
  25557. independently of what is declared in the @code{operating-system} file
  25558. passed as argument. This is to make it easier to work with QEMU, which
  25559. uses the SeaBIOS BIOS by default, expecting a bootloader to be installed
  25560. in the Master Boot Record (MBR).
  25561. @cindex docker-image, creating docker images
  25562. When using @code{docker-image}, a Docker image is produced. Guix builds
  25563. the image from scratch, not from a pre-existing Docker base image. As a
  25564. result, it contains @emph{exactly} what you define in the operating
  25565. system configuration file. You can then load the image and launch a
  25566. Docker container using commands like the following:
  25567. @example
  25568. image_id="`docker load < guix-system-docker-image.tar.gz`"
  25569. container_id="`docker create $image_id`"
  25570. docker start $container_id
  25571. @end example
  25572. This command starts a new Docker container from the specified image. It
  25573. will boot the Guix system in the usual manner, which means it will
  25574. start any services you have defined in the operating system
  25575. configuration. You can get an interactive shell running in the container
  25576. using @command{docker exec}:
  25577. @example
  25578. docker exec -ti $container_id /run/current-system/profile/bin/bash --login
  25579. @end example
  25580. Depending on what you run in the Docker container, it
  25581. may be necessary to give the container additional permissions. For
  25582. example, if you intend to build software using Guix inside of the Docker
  25583. container, you may need to pass the @option{--privileged} option to
  25584. @code{docker create}.
  25585. Last, the @option{--network} option applies to @command{guix system
  25586. docker-image}: it produces an image where network is supposedly shared
  25587. with the host, and thus without services like nscd or NetworkManager.
  25588. @item container
  25589. Return a script to run the operating system declared in @var{file}
  25590. within a container. Containers are a set of lightweight isolation
  25591. mechanisms provided by the kernel Linux-libre. Containers are
  25592. substantially less resource-demanding than full virtual machines since
  25593. the kernel, shared objects, and other resources can be shared with the
  25594. host system; this also means they provide thinner isolation.
  25595. Currently, the script must be run as root in order to support more than
  25596. a single user and group. The container shares its store with the host
  25597. system.
  25598. As with the @code{vm} action (@pxref{guix system vm}), additional file
  25599. systems to be shared between the host and container can be specified
  25600. using the @option{--share} and @option{--expose} options:
  25601. @example
  25602. guix system container my-config.scm \
  25603. --expose=$HOME --share=$HOME/tmp=/exchange
  25604. @end example
  25605. @quotation Note
  25606. This option requires Linux-libre 3.19 or newer.
  25607. @end quotation
  25608. @end table
  25609. @var{options} can contain any of the common build options (@pxref{Common
  25610. Build Options}). In addition, @var{options} can contain one of the
  25611. following:
  25612. @table @option
  25613. @item --expression=@var{expr}
  25614. @itemx -e @var{expr}
  25615. Consider the operating-system @var{expr} evaluates to.
  25616. This is an alternative to specifying a file which evaluates to an
  25617. operating system.
  25618. This is used to generate the Guix system installer @pxref{Building the
  25619. Installation Image}).
  25620. @item --system=@var{system}
  25621. @itemx -s @var{system}
  25622. Attempt to build for @var{system} instead of the host system type.
  25623. This works as per @command{guix build} (@pxref{Invoking guix build}).
  25624. @item --derivation
  25625. @itemx -d
  25626. Return the derivation file name of the given operating system without
  25627. building anything.
  25628. @cindex provenance tracking, of the operating system
  25629. @item --save-provenance
  25630. As discussed above, @command{guix system init} and @command{guix system
  25631. reconfigure} always save provenance information @i{via} a dedicated
  25632. service (@pxref{Service Reference, @code{provenance-service-type}}).
  25633. However, other commands don't do that by default. If you wish to, say,
  25634. create a virtual machine image that contains provenance information, you
  25635. can run:
  25636. @example
  25637. guix system image -t qcow2 --save-provenance config.scm
  25638. @end example
  25639. That way, the resulting image will effectively ``embed its own source''
  25640. in the form of meta-data in @file{/run/current-system}. With that
  25641. information, one can rebuild the image to make sure it really contains
  25642. what it pretends to contain; or they could use that to derive a variant
  25643. of the image.
  25644. @item --image-type=@var{type}
  25645. @itemx -t @var{type}
  25646. For the @code{image} action, create an image with given @var{type}.
  25647. When this option is omitted, @command{guix system} uses the
  25648. @code{efi-raw} image type.
  25649. @cindex ISO-9660 format
  25650. @cindex CD image format
  25651. @cindex DVD image format
  25652. @option{--image-type=iso9660} produces an ISO-9660 image, suitable
  25653. for burning on CDs and DVDs.
  25654. @item --image-size=@var{size}
  25655. For the @code{image} action, create an image of the given @var{size}.
  25656. @var{size} may be a number of bytes, or it may include a unit as a
  25657. suffix (@pxref{Block size, size specifications,, coreutils, GNU
  25658. Coreutils}).
  25659. When this option is omitted, @command{guix system} computes an estimate
  25660. of the image size as a function of the size of the system declared in
  25661. @var{file}.
  25662. @item --network
  25663. @itemx -N
  25664. For the @code{container} action, allow containers to access the host network,
  25665. that is, do not create a network namespace.
  25666. @item --root=@var{file}
  25667. @itemx -r @var{file}
  25668. Make @var{file} a symlink to the result, and register it as a garbage
  25669. collector root.
  25670. @item --skip-checks
  25671. Skip pre-installation safety checks.
  25672. By default, @command{guix system init} and @command{guix system
  25673. reconfigure} perform safety checks: they make sure the file systems that
  25674. appear in the @code{operating-system} declaration actually exist
  25675. (@pxref{File Systems}), and that any Linux kernel modules that may be
  25676. needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
  25677. RAM Disk}). Passing this option skips these tests altogether.
  25678. @item --allow-downgrades
  25679. Instruct @command{guix system reconfigure} to allow system downgrades.
  25680. By default, @command{reconfigure} prevents you from downgrading your
  25681. system. It achieves that by comparing the provenance info of your
  25682. system (shown by @command{guix system describe}) with that of your
  25683. @command{guix} command (shown by @command{guix describe}). If the
  25684. commits for @command{guix} are not descendants of those used for your
  25685. system, @command{guix system reconfigure} errors out. Passing
  25686. @option{--allow-downgrades} allows you to bypass these checks.
  25687. @quotation Note
  25688. Make sure you understand its security implications before using
  25689. @option{--allow-downgrades}.
  25690. @end quotation
  25691. @cindex on-error
  25692. @cindex on-error strategy
  25693. @cindex error strategy
  25694. @item --on-error=@var{strategy}
  25695. Apply @var{strategy} when an error occurs when reading @var{file}.
  25696. @var{strategy} may be one of the following:
  25697. @table @code
  25698. @item nothing-special
  25699. Report the error concisely and exit. This is the default strategy.
  25700. @item backtrace
  25701. Likewise, but also display a backtrace.
  25702. @item debug
  25703. Report the error and enter Guile's debugger. From there, you can run
  25704. commands such as @code{,bt} to get a backtrace, @code{,locals} to
  25705. display local variable values, and more generally inspect the state of the
  25706. program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
  25707. a list of available debugging commands.
  25708. @end table
  25709. @end table
  25710. Once you have built, configured, re-configured, and re-re-configured
  25711. your Guix installation, you may find it useful to list the operating
  25712. system generations available on disk---and that you can choose from the
  25713. bootloader boot menu:
  25714. @table @code
  25715. @item describe
  25716. Describe the current system generation: its file name, the kernel and
  25717. bootloader used, etc., as well as provenance information when available.
  25718. @item list-generations
  25719. List a summary of each generation of the operating system available on
  25720. disk, in a human-readable way. This is similar to the
  25721. @option{--list-generations} option of @command{guix package}
  25722. (@pxref{Invoking guix package}).
  25723. Optionally, one can specify a pattern, with the same syntax that is used
  25724. in @command{guix package --list-generations}, to restrict the list of
  25725. generations displayed. For instance, the following command displays
  25726. generations that are up to 10 days old:
  25727. @example
  25728. $ guix system list-generations 10d
  25729. @end example
  25730. @end table
  25731. The @command{guix system} command has even more to offer! The following
  25732. sub-commands allow you to visualize how your system services relate to
  25733. each other:
  25734. @anchor{system-extension-graph}
  25735. @table @code
  25736. @item extension-graph
  25737. Emit to standard output the @dfn{service
  25738. extension graph} of the operating system defined in @var{file}
  25739. (@pxref{Service Composition}, for more information on service
  25740. extensions). By default the output is in Dot/Graphviz format, but you
  25741. can choose a different format with @option{--graph-backend}, as with
  25742. @command{guix graph} (@pxref{Invoking guix graph, @option{--backend}}):
  25743. The command:
  25744. @example
  25745. $ guix system extension-graph @var{file} | xdot -
  25746. @end example
  25747. shows the extension relations among services.
  25748. @anchor{system-shepherd-graph}
  25749. @item shepherd-graph
  25750. Emit to standard output the @dfn{dependency
  25751. graph} of shepherd services of the operating system defined in
  25752. @var{file}. @xref{Shepherd Services}, for more information and for an
  25753. example graph.
  25754. Again, the default output format is Dot/Graphviz, but you can pass
  25755. @option{--graph-backend} to select a different one.
  25756. @end table
  25757. @node Invoking guix deploy
  25758. @section Invoking @code{guix deploy}
  25759. We've already seen @code{operating-system} declarations used to manage a
  25760. machine's configuration locally. Suppose you need to configure multiple
  25761. machines, though---perhaps you're managing a service on the web that's
  25762. comprised of several servers. @command{guix deploy} enables you to use those
  25763. same @code{operating-system} declarations to manage multiple remote hosts at
  25764. once as a logical ``deployment''.
  25765. @quotation Note
  25766. The functionality described in this section is still under development
  25767. and is subject to change. Get in touch with us on
  25768. @email{guix-devel@@gnu.org}!
  25769. @end quotation
  25770. @example
  25771. guix deploy @var{file}
  25772. @end example
  25773. Such an invocation will deploy the machines that the code within @var{file}
  25774. evaluates to. As an example, @var{file} might contain a definition like this:
  25775. @lisp
  25776. ;; This is a Guix deployment of a "bare bones" setup, with
  25777. ;; no X11 display server, to a machine with an SSH daemon
  25778. ;; listening on localhost:2222. A configuration such as this
  25779. ;; may be appropriate for virtual machine with ports
  25780. ;; forwarded to the host's loopback interface.
  25781. (use-service-modules networking ssh)
  25782. (use-package-modules bootloaders)
  25783. (define %system
  25784. (operating-system
  25785. (host-name "gnu-deployed")
  25786. (timezone "Etc/UTC")
  25787. (bootloader (bootloader-configuration
  25788. (bootloader grub-bootloader)
  25789. (target "/dev/vda")
  25790. (terminal-outputs '(console))))
  25791. (file-systems (cons (file-system
  25792. (mount-point "/")
  25793. (device "/dev/vda1")
  25794. (type "ext4"))
  25795. %base-file-systems))
  25796. (services
  25797. (append (list (service dhcp-client-service-type)
  25798. (service openssh-service-type
  25799. (openssh-configuration
  25800. (permit-root-login #t)
  25801. (allow-empty-passwords? #t))))
  25802. %base-services))))
  25803. (list (machine
  25804. (operating-system %system)
  25805. (environment managed-host-environment-type)
  25806. (configuration (machine-ssh-configuration
  25807. (host-name "localhost")
  25808. (system "x86_64-linux")
  25809. (user "alice")
  25810. (identity "./id_rsa")
  25811. (port 2222)))))
  25812. @end lisp
  25813. The file should evaluate to a list of @var{machine} objects. This example,
  25814. upon being deployed, will create a new generation on the remote system
  25815. realizing the @code{operating-system} declaration @code{%system}.
  25816. @code{environment} and @code{configuration} specify how the machine should be
  25817. provisioned---that is, how the computing resources should be created and
  25818. managed. The above example does not create any resources, as a
  25819. @code{'managed-host} is a machine that is already running the Guix system and
  25820. available over the network. This is a particularly simple case; a more
  25821. complex deployment may involve, for example, starting virtual machines through
  25822. a Virtual Private Server (VPS) provider. In such a case, a different
  25823. @var{environment} type would be used.
  25824. Do note that you first need to generate a key pair on the coordinator machine
  25825. to allow the daemon to export signed archives of files from the store
  25826. (@pxref{Invoking guix archive}), though this step is automatic on Guix
  25827. System:
  25828. @example
  25829. # guix archive --generate-key
  25830. @end example
  25831. @noindent
  25832. Each target machine must authorize the key of the master machine so that it
  25833. accepts store items it receives from the coordinator:
  25834. @example
  25835. # guix archive --authorize < coordinator-public-key.txt
  25836. @end example
  25837. @code{user}, in this example, specifies the name of the user account to log in
  25838. as to perform the deployment. Its default value is @code{root}, but root
  25839. login over SSH may be forbidden in some cases. To work around this,
  25840. @command{guix deploy} can log in as an unprivileged user and employ
  25841. @code{sudo} to escalate privileges. This will only work if @code{sudo} is
  25842. currently installed on the remote and can be invoked non-interactively as
  25843. @code{user}. That is, the line in @code{sudoers} granting @code{user} the
  25844. ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
  25845. be accomplished with the following operating system configuration snippet:
  25846. @lisp
  25847. (use-modules ...
  25848. (gnu system)) ;for %sudoers-specification
  25849. (define %user "username")
  25850. (operating-system
  25851. ...
  25852. (sudoers-file
  25853. (plain-file "sudoers"
  25854. (string-append (plain-file-content %sudoers-specification)
  25855. (format #f "~a ALL = NOPASSWD: ALL~%"
  25856. %user)))))
  25857. @end lisp
  25858. For more information regarding the format of the @file{sudoers} file,
  25859. consult @command{man sudoers}.
  25860. @deftp {Data Type} machine
  25861. This is the data type representing a single machine in a heterogeneous Guix
  25862. deployment.
  25863. @table @asis
  25864. @item @code{operating-system}
  25865. The object of the operating system configuration to deploy.
  25866. @item @code{environment}
  25867. An @code{environment-type} describing how the machine should be provisioned.
  25868. @item @code{configuration} (default: @code{#f})
  25869. An object describing the configuration for the machine's @code{environment}.
  25870. If the @code{environment} has a default configuration, @code{#f} may be used.
  25871. If @code{#f} is used for an environment with no default configuration,
  25872. however, an error will be thrown.
  25873. @end table
  25874. @end deftp
  25875. @deftp {Data Type} machine-ssh-configuration
  25876. This is the data type representing the SSH client parameters for a machine
  25877. with an @code{environment} of @code{managed-host-environment-type}.
  25878. @table @asis
  25879. @item @code{host-name}
  25880. @item @code{build-locally?} (default: @code{#t})
  25881. If false, system derivations will be built on the machine being deployed to.
  25882. @item @code{system}
  25883. The system type describing the architecture of the machine being deployed
  25884. to---e.g., @code{"x86_64-linux"}.
  25885. @item @code{authorize?} (default: @code{#t})
  25886. If true, the coordinator's signing key will be added to the remote's ACL
  25887. keyring.
  25888. @item @code{port} (default: @code{22})
  25889. @item @code{user} (default: @code{"root"})
  25890. @item @code{identity} (default: @code{#f})
  25891. If specified, the path to the SSH private key to use to authenticate with the
  25892. remote host.
  25893. @item @code{host-key} (default: @code{#f})
  25894. This should be the SSH host key of the machine, which looks like this:
  25895. @example
  25896. ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
  25897. @end example
  25898. When @code{host-key} is @code{#f}, the server is authenticated against
  25899. the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
  25900. client does.
  25901. @item @code{allow-downgrades?} (default: @code{#f})
  25902. Whether to allow potential downgrades.
  25903. Like @command{guix system reconfigure}, @command{guix deploy} compares
  25904. the channel commits currently deployed on the remote host (as returned
  25905. by @command{guix system describe}) to those currently in use (as
  25906. returned by @command{guix describe}) to determine whether commits
  25907. currently in use are descendants of those deployed. When this is not
  25908. the case and @code{allow-downgrades?} is false, it raises an error.
  25909. This ensures you do not accidentally downgrade remote machines.
  25910. @end table
  25911. @end deftp
  25912. @deftp {Data Type} digital-ocean-configuration
  25913. This is the data type describing the Droplet that should be created for a
  25914. machine with an @code{environment} of @code{digital-ocean-environment-type}.
  25915. @table @asis
  25916. @item @code{ssh-key}
  25917. The path to the SSH private key to use to authenticate with the remote
  25918. host. In the future, this field may not exist.
  25919. @item @code{tags}
  25920. A list of string ``tags'' that uniquely identify the machine. Must be given
  25921. such that no two machines in the deployment have the same set of tags.
  25922. @item @code{region}
  25923. A Digital Ocean region slug, such as @code{"nyc3"}.
  25924. @item @code{size}
  25925. A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
  25926. @item @code{enable-ipv6?}
  25927. Whether or not the droplet should be created with IPv6 networking.
  25928. @end table
  25929. @end deftp
  25930. @node Running Guix in a VM
  25931. @section Running Guix in a Virtual Machine
  25932. @cindex virtual machine
  25933. To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
  25934. distributed at
  25935. @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
  25936. This image is a compressed image in QCOW format. You will first need to
  25937. decompress with @command{xz -d}, and then you can pass it to an emulator such
  25938. as QEMU (see below for details).
  25939. This image boots the Xfce graphical environment and it contains some
  25940. commonly used tools. You can install more software in the image by running
  25941. @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
  25942. also reconfigure the system based on its initial configuration file available
  25943. as @file{/run/current-system/configuration.scm} (@pxref{Using the
  25944. Configuration System}).
  25945. Instead of using this pre-built image, one can also build their own virtual
  25946. machine image using @command{guix system vm-image} (@pxref{Invoking guix
  25947. system}). The returned image is in qcow2 format, which the
  25948. @uref{https://qemu.org/, QEMU emulator} can efficiently use.
  25949. @cindex QEMU
  25950. If you built your own image, you must copy it out of the store
  25951. (@pxref{The Store}) and give yourself permission to write to the copy
  25952. before you can use it. When invoking QEMU, you must choose a system
  25953. emulator that is suitable for your hardware platform. Here is a minimal
  25954. QEMU invocation that will boot the result of @command{guix system
  25955. image -t qcow2} on x86_64 hardware:
  25956. @example
  25957. $ qemu-system-x86_64 \
  25958. -nic user,model=virtio-net-pci \
  25959. -enable-kvm -m 1024 \
  25960. -device virtio-blk,drive=myhd \
  25961. -drive if=none,file=/tmp/qemu-image,id=myhd
  25962. @end example
  25963. Here is what each of these options means:
  25964. @table @code
  25965. @item qemu-system-x86_64
  25966. This specifies the hardware platform to emulate. This should match the
  25967. host.
  25968. @item -nic user,model=virtio-net-pci
  25969. Enable the unprivileged user-mode network stack. The guest OS can
  25970. access the host but not vice versa. This is the simplest way to get the
  25971. guest OS online. @code{model} specifies which network device to emulate:
  25972. @code{virtio-net-pci} is a special device made for virtualized operating
  25973. systems and recommended for most uses. Assuming your hardware platform is
  25974. x86_64, you can get a list of available NIC models by running
  25975. @command{qemu-system-x86_64 -nic model=help}.
  25976. @item -enable-kvm
  25977. If your system has hardware virtualization extensions, enabling the
  25978. virtual machine support (KVM) of the Linux kernel will make things run
  25979. faster.
  25980. @c To run Xfce + 'guix pull', we need at least 1G of RAM.
  25981. @item -m 1024
  25982. RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
  25983. which may be insufficient for some operations.
  25984. @item -device virtio-blk,drive=myhd
  25985. Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
  25986. ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
  25987. better performance than if it were emulating a complete disk drive. See the
  25988. QEMU and KVM documentation for more info.
  25989. @item -drive if=none,file=/tmp/qemu-image,id=myhd
  25990. Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing
  25991. store of the ``myhd'' drive.
  25992. @end table
  25993. The default @command{run-vm.sh} script that is returned by an invocation of
  25994. @command{guix system vm} does not add a @command{-nic user} flag by default.
  25995. To get network access from within the vm add the @code{(dhcp-client-service)}
  25996. to your system definition and start the VM using
  25997. @command{`guix system vm config.scm` -nic user}. An important caveat of using
  25998. @command{-nic user} for networking is that @command{ping} will not work, because
  25999. it uses the ICMP protocol. You'll have to use a different command to check for
  26000. network connectivity, for example @command{guix download}.
  26001. @subsection Connecting Through SSH
  26002. @cindex SSH
  26003. @cindex SSH server
  26004. To enable SSH inside a VM you need to add an SSH server like
  26005. @code{openssh-service-type} to your VM (@pxref{Networking Services,
  26006. @code{openssh-service-type}}). In addition you need to forward the SSH port,
  26007. 22 by default, to the host. You can do this with
  26008. @example
  26009. `guix system vm config.scm` -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
  26010. @end example
  26011. To connect to the VM you can run
  26012. @example
  26013. ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
  26014. @end example
  26015. The @command{-p} tells @command{ssh} the port you want to connect to.
  26016. @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
  26017. every time you modify your @command{config.scm} file and the
  26018. @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
  26019. connection to an unknown host every time you connect.
  26020. @subsection Using @command{virt-viewer} with Spice
  26021. As an alternative to the default @command{qemu} graphical client you can
  26022. use the @command{remote-viewer} from the @command{virt-viewer} package. To
  26023. connect pass the @command{-spice port=5930,disable-ticketing} flag to
  26024. @command{qemu}. See previous section for further information on how to do this.
  26025. Spice also allows you to do some nice stuff like share your clipboard with your
  26026. VM@. To enable that you'll also have to pass the following flags to @command{qemu}:
  26027. @example
  26028. -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
  26029. -chardev spicevmc,name=vdagent,id=vdagent
  26030. -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
  26031. name=com.redhat.spice.0
  26032. @end example
  26033. You'll also need to add the @code{(spice-vdagent-service)} to your
  26034. system definition (@pxref{Miscellaneous Services, Spice service}).
  26035. @node Defining Services
  26036. @section Defining Services
  26037. The previous sections show the available services and how one can combine
  26038. them in an @code{operating-system} declaration. But how do we define
  26039. them in the first place? And what is a service anyway?
  26040. @menu
  26041. * Service Composition:: The model for composing services.
  26042. * Service Types and Services:: Types and services.
  26043. * Service Reference:: API reference.
  26044. * Shepherd Services:: A particular type of service.
  26045. @end menu
  26046. @node Service Composition
  26047. @subsection Service Composition
  26048. @cindex services
  26049. @cindex daemons
  26050. Here we define a @dfn{service} as, broadly, something that extends the
  26051. functionality of the operating system. Often a service is a process---a
  26052. @dfn{daemon}---started when the system boots: a secure shell server, a
  26053. Web server, the Guix build daemon, etc. Sometimes a service is a daemon
  26054. whose execution can be triggered by another daemon---e.g., an FTP server
  26055. started by @command{inetd} or a D-Bus service activated by
  26056. @command{dbus-daemon}. Occasionally, a service does not map to a
  26057. daemon. For instance, the ``account'' service collects user accounts
  26058. and makes sure they exist when the system runs; the ``udev'' service
  26059. collects device management rules and makes them available to the eudev
  26060. daemon; the @file{/etc} service populates the @file{/etc} directory
  26061. of the system.
  26062. @cindex service extensions
  26063. Guix system services are connected by @dfn{extensions}. For instance, the
  26064. secure shell service @emph{extends} the Shepherd---the
  26065. initialization system, running as PID@tie{}1---by giving it the command
  26066. lines to start and stop the secure shell daemon (@pxref{Networking
  26067. Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
  26068. service by passing it its @file{.service} specification, and extends the
  26069. udev service by passing it device management rules (@pxref{Desktop
  26070. Services, @code{upower-service}}); the Guix daemon service extends the
  26071. Shepherd by passing it the command lines to start and stop the daemon,
  26072. and extends the account service by passing it a list of required build
  26073. user accounts (@pxref{Base Services}).
  26074. All in all, services and their ``extends'' relations form a directed
  26075. acyclic graph (DAG). If we represent services as boxes and extensions
  26076. as arrows, a typical system might provide something like this:
  26077. @image{images/service-graph,,5in,Typical service extension graph.}
  26078. @cindex system service
  26079. At the bottom, we see the @dfn{system service}, which produces the
  26080. directory containing everything to run and boot the system, as returned
  26081. by the @command{guix system build} command. @xref{Service Reference},
  26082. to learn about the other service types shown here.
  26083. @xref{system-extension-graph, the @command{guix system extension-graph}
  26084. command}, for information on how to generate this representation for a
  26085. particular operating system definition.
  26086. @cindex service types
  26087. Technically, developers can define @dfn{service types} to express these
  26088. relations. There can be any number of services of a given type on the
  26089. system---for instance, a system running two instances of the GNU secure
  26090. shell server (lsh) has two instances of @code{lsh-service-type}, with
  26091. different parameters.
  26092. The following section describes the programming interface for service
  26093. types and services.
  26094. @node Service Types and Services
  26095. @subsection Service Types and Services
  26096. A @dfn{service type} is a node in the DAG described above. Let us start
  26097. with a simple example, the service type for the Guix build daemon
  26098. (@pxref{Invoking guix-daemon}):
  26099. @lisp
  26100. (define guix-service-type
  26101. (service-type
  26102. (name 'guix)
  26103. (extensions
  26104. (list (service-extension shepherd-root-service-type guix-shepherd-service)
  26105. (service-extension account-service-type guix-accounts)
  26106. (service-extension activation-service-type guix-activation)))
  26107. (default-value (guix-configuration))))
  26108. @end lisp
  26109. @noindent
  26110. It defines three things:
  26111. @enumerate
  26112. @item
  26113. A name, whose sole purpose is to make inspection and debugging easier.
  26114. @item
  26115. A list of @dfn{service extensions}, where each extension designates the
  26116. target service type and a procedure that, given the parameters of the
  26117. service, returns a list of objects to extend the service of that type.
  26118. Every service type has at least one service extension. The only
  26119. exception is the @dfn{boot service type}, which is the ultimate service.
  26120. @item
  26121. Optionally, a default value for instances of this type.
  26122. @end enumerate
  26123. In this example, @code{guix-service-type} extends three services:
  26124. @table @code
  26125. @item shepherd-root-service-type
  26126. The @code{guix-shepherd-service} procedure defines how the Shepherd
  26127. service is extended. Namely, it returns a @code{<shepherd-service>}
  26128. object that defines how @command{guix-daemon} is started and stopped
  26129. (@pxref{Shepherd Services}).
  26130. @item account-service-type
  26131. This extension for this service is computed by @code{guix-accounts},
  26132. which returns a list of @code{user-group} and @code{user-account}
  26133. objects representing the build user accounts (@pxref{Invoking
  26134. guix-daemon}).
  26135. @item activation-service-type
  26136. Here @code{guix-activation} is a procedure that returns a gexp, which is
  26137. a code snippet to run at ``activation time''---e.g., when the service is
  26138. booted.
  26139. @end table
  26140. A service of this type is instantiated like this:
  26141. @lisp
  26142. (service guix-service-type
  26143. (guix-configuration
  26144. (build-accounts 5)
  26145. (extra-options '("--gc-keep-derivations"))))
  26146. @end lisp
  26147. The second argument to the @code{service} form is a value representing
  26148. the parameters of this specific service instance.
  26149. @xref{guix-configuration-type, @code{guix-configuration}}, for
  26150. information about the @code{guix-configuration} data type. When the
  26151. value is omitted, the default value specified by
  26152. @code{guix-service-type} is used:
  26153. @lisp
  26154. (service guix-service-type)
  26155. @end lisp
  26156. @code{guix-service-type} is quite simple because it extends other
  26157. services but is not extensible itself.
  26158. @c @subsubsubsection Extensible Service Types
  26159. The service type for an @emph{extensible} service looks like this:
  26160. @lisp
  26161. (define udev-service-type
  26162. (service-type (name 'udev)
  26163. (extensions
  26164. (list (service-extension shepherd-root-service-type
  26165. udev-shepherd-service)))
  26166. (compose concatenate) ;concatenate the list of rules
  26167. (extend (lambda (config rules)
  26168. (match config
  26169. (($ <udev-configuration> udev initial-rules)
  26170. (udev-configuration
  26171. (udev udev) ;the udev package to use
  26172. (rules (append initial-rules rules)))))))))
  26173. @end lisp
  26174. This is the service type for the
  26175. @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
  26176. management daemon}. Compared to the previous example, in addition to an
  26177. extension of @code{shepherd-root-service-type}, we see two new fields:
  26178. @table @code
  26179. @item compose
  26180. This is the procedure to @dfn{compose} the list of extensions to
  26181. services of this type.
  26182. Services can extend the udev service by passing it lists of rules; we
  26183. compose those extensions simply by concatenating them.
  26184. @item extend
  26185. This procedure defines how the value of the service is @dfn{extended} with
  26186. the composition of the extensions.
  26187. Udev extensions are composed into a list of rules, but the udev service
  26188. value is itself a @code{<udev-configuration>} record. So here, we
  26189. extend that record by appending the list of rules it contains to the
  26190. list of contributed rules.
  26191. @item description
  26192. This is a string giving an overview of the service type. The string can
  26193. contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
  26194. @command{guix system search} command searches these strings and displays
  26195. them (@pxref{Invoking guix system}).
  26196. @end table
  26197. There can be only one instance of an extensible service type such as
  26198. @code{udev-service-type}. If there were more, the
  26199. @code{service-extension} specifications would be ambiguous.
  26200. Still here? The next section provides a reference of the programming
  26201. interface for services.
  26202. @node Service Reference
  26203. @subsection Service Reference
  26204. We have seen an overview of service types (@pxref{Service Types and
  26205. Services}). This section provides a reference on how to manipulate
  26206. services and service types. This interface is provided by the
  26207. @code{(gnu services)} module.
  26208. @deffn {Scheme Procedure} service @var{type} [@var{value}]
  26209. Return a new service of @var{type}, a @code{<service-type>} object (see
  26210. below). @var{value} can be any object; it represents the parameters of
  26211. this particular service instance.
  26212. When @var{value} is omitted, the default value specified by @var{type}
  26213. is used; if @var{type} does not specify a default value, an error is
  26214. raised.
  26215. For instance, this:
  26216. @lisp
  26217. (service openssh-service-type)
  26218. @end lisp
  26219. @noindent
  26220. is equivalent to this:
  26221. @lisp
  26222. (service openssh-service-type
  26223. (openssh-configuration))
  26224. @end lisp
  26225. In both cases the result is an instance of @code{openssh-service-type}
  26226. with the default configuration.
  26227. @end deffn
  26228. @deffn {Scheme Procedure} service? @var{obj}
  26229. Return true if @var{obj} is a service.
  26230. @end deffn
  26231. @deffn {Scheme Procedure} service-kind @var{service}
  26232. Return the type of @var{service}---i.e., a @code{<service-type>} object.
  26233. @end deffn
  26234. @deffn {Scheme Procedure} service-value @var{service}
  26235. Return the value associated with @var{service}. It represents its
  26236. parameters.
  26237. @end deffn
  26238. Here is an example of how a service is created and manipulated:
  26239. @lisp
  26240. (define s
  26241. (service nginx-service-type
  26242. (nginx-configuration
  26243. (nginx nginx)
  26244. (log-directory log-directory)
  26245. (run-directory run-directory)
  26246. (file config-file))))
  26247. (service? s)
  26248. @result{} #t
  26249. (eq? (service-kind s) nginx-service-type)
  26250. @result{} #t
  26251. @end lisp
  26252. The @code{modify-services} form provides a handy way to change the
  26253. parameters of some of the services of a list such as
  26254. @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
  26255. evaluates to a list of services. Of course, you could always use
  26256. standard list combinators such as @code{map} and @code{fold} to do that
  26257. (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
  26258. @code{modify-services} simply provides a more concise form for this
  26259. common pattern.
  26260. @deffn {Scheme Syntax} modify-services @var{services} @
  26261. (@var{type} @var{variable} => @var{body}) @dots{}
  26262. Modify the services listed in @var{services} according to the given
  26263. clauses. Each clause has the form:
  26264. @example
  26265. (@var{type} @var{variable} => @var{body})
  26266. @end example
  26267. where @var{type} is a service type---e.g.,
  26268. @code{guix-service-type}---and @var{variable} is an identifier that is
  26269. bound within the @var{body} to the service parameters---e.g., a
  26270. @code{guix-configuration} instance---of the original service of that
  26271. @var{type}.
  26272. The @var{body} should evaluate to the new service parameters, which will
  26273. be used to configure the new service. This new service will replace the
  26274. original in the resulting list. Because a service's service parameters
  26275. are created using @code{define-record-type*}, you can write a succinct
  26276. @var{body} that evaluates to the new service parameters by using the
  26277. @code{inherit} feature that @code{define-record-type*} provides.
  26278. @xref{Using the Configuration System}, for example usage.
  26279. @end deffn
  26280. Next comes the programming interface for service types. This is
  26281. something you want to know when writing new service definitions, but not
  26282. necessarily when simply looking for ways to customize your
  26283. @code{operating-system} declaration.
  26284. @deftp {Data Type} service-type
  26285. @cindex service type
  26286. This is the representation of a @dfn{service type} (@pxref{Service Types
  26287. and Services}).
  26288. @table @asis
  26289. @item @code{name}
  26290. This is a symbol, used only to simplify inspection and debugging.
  26291. @item @code{extensions}
  26292. A non-empty list of @code{<service-extension>} objects (see below).
  26293. @item @code{compose} (default: @code{#f})
  26294. If this is @code{#f}, then the service type denotes services that cannot
  26295. be extended---i.e., services that do not receive ``values'' from other
  26296. services.
  26297. Otherwise, it must be a one-argument procedure. The procedure is called
  26298. by @code{fold-services} and is passed a list of values collected from
  26299. extensions. It may return any single value.
  26300. @item @code{extend} (default: @code{#f})
  26301. If this is @code{#f}, services of this type cannot be extended.
  26302. Otherwise, it must be a two-argument procedure: @code{fold-services}
  26303. calls it, passing it the initial value of the service as the first
  26304. argument and the result of applying @code{compose} to the extension
  26305. values as the second argument. It must return a value that is a valid
  26306. parameter value for the service instance.
  26307. @item @code{description}
  26308. This is a string, possibly using Texinfo markup, describing in a couple
  26309. of sentences what the service is about. This string allows users to
  26310. find about the service through @command{guix system search}
  26311. (@pxref{Invoking guix system}).
  26312. @item @code{default-value} (default: @code{&no-default-value})
  26313. The default value associated for instances of this service type. This
  26314. allows users to use the @code{service} form without its second argument:
  26315. @lisp
  26316. (service @var{type})
  26317. @end lisp
  26318. The returned service in this case has the default value specified by
  26319. @var{type}.
  26320. @end table
  26321. @xref{Service Types and Services}, for examples.
  26322. @end deftp
  26323. @deffn {Scheme Procedure} service-extension @var{target-type} @
  26324. @var{compute}
  26325. Return a new extension for services of type @var{target-type}.
  26326. @var{compute} must be a one-argument procedure: @code{fold-services}
  26327. calls it, passing it the value associated with the service that provides
  26328. the extension; it must return a valid value for the target service.
  26329. @end deffn
  26330. @deffn {Scheme Procedure} service-extension? @var{obj}
  26331. Return true if @var{obj} is a service extension.
  26332. @end deffn
  26333. Occasionally, you might want to simply extend an existing service. This
  26334. involves creating a new service type and specifying the extension of
  26335. interest, which can be verbose; the @code{simple-service} procedure
  26336. provides a shorthand for this.
  26337. @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
  26338. Return a service that extends @var{target} with @var{value}. This works
  26339. by creating a singleton service type @var{name}, of which the returned
  26340. service is an instance.
  26341. For example, this extends mcron (@pxref{Scheduled Job Execution}) with
  26342. an additional job:
  26343. @lisp
  26344. (simple-service 'my-mcron-job mcron-service-type
  26345. #~(job '(next-hour (3)) "guix gc -F 2G"))
  26346. @end lisp
  26347. @end deffn
  26348. At the core of the service abstraction lies the @code{fold-services}
  26349. procedure, which is responsible for ``compiling'' a list of services
  26350. down to a single directory that contains everything needed to boot and
  26351. run the system---the directory shown by the @command{guix system build}
  26352. command (@pxref{Invoking guix system}). In essence, it propagates
  26353. service extensions down the service graph, updating each node parameters
  26354. on the way, until it reaches the root node.
  26355. @deffn {Scheme Procedure} fold-services @var{services} @
  26356. [#:target-type @var{system-service-type}]
  26357. Fold @var{services} by propagating their extensions down to the root of
  26358. type @var{target-type}; return the root service adjusted accordingly.
  26359. @end deffn
  26360. Lastly, the @code{(gnu services)} module also defines several essential
  26361. service types, some of which are listed below.
  26362. @defvr {Scheme Variable} system-service-type
  26363. This is the root of the service graph. It produces the system directory
  26364. as returned by the @command{guix system build} command.
  26365. @end defvr
  26366. @defvr {Scheme Variable} boot-service-type
  26367. The type of the ``boot service'', which produces the @dfn{boot script}.
  26368. The boot script is what the initial RAM disk runs when booting.
  26369. @end defvr
  26370. @defvr {Scheme Variable} etc-service-type
  26371. The type of the @file{/etc} service. This service is used to create
  26372. files under @file{/etc} and can be extended by
  26373. passing it name/file tuples such as:
  26374. @lisp
  26375. (list `("issue" ,(plain-file "issue" "Welcome!\n")))
  26376. @end lisp
  26377. In this example, the effect would be to add an @file{/etc/issue} file
  26378. pointing to the given file.
  26379. @end defvr
  26380. @defvr {Scheme Variable} setuid-program-service-type
  26381. Type for the ``setuid-program service''. This service collects lists of
  26382. executable file names, passed as gexps, and adds them to the set of
  26383. setuid-root programs on the system (@pxref{Setuid Programs}).
  26384. @end defvr
  26385. @defvr {Scheme Variable} profile-service-type
  26386. Type of the service that populates the @dfn{system profile}---i.e., the
  26387. programs under @file{/run/current-system/profile}. Other services can
  26388. extend it by passing it lists of packages to add to the system profile.
  26389. @end defvr
  26390. @cindex provenance tracking, of the operating system
  26391. @anchor{provenance-service-type}
  26392. @defvr {Scheme Variable} provenance-service-type
  26393. This is the type of the service that records @dfn{provenance meta-data}
  26394. in the system itself. It creates several files under
  26395. @file{/run/current-system}:
  26396. @table @file
  26397. @item channels.scm
  26398. This is a ``channel file'' that can be passed to @command{guix pull -C}
  26399. or @command{guix time-machine -C}, and which describes the channels used
  26400. to build the system, if that information was available
  26401. (@pxref{Channels}).
  26402. @item configuration.scm
  26403. This is the file that was passed as the value for this
  26404. @code{provenance-service-type} service. By default, @command{guix
  26405. system reconfigure} automatically passes the OS configuration file it
  26406. received on the command line.
  26407. @item provenance
  26408. This contains the same information as the two other files but in a
  26409. format that is more readily processable.
  26410. @end table
  26411. In general, these two pieces of information (channels and configuration
  26412. file) are enough to reproduce the operating system ``from source''.
  26413. @quotation Caveats
  26414. This information is necessary to rebuild your operating system, but it
  26415. is not always sufficient. In particular, @file{configuration.scm}
  26416. itself is insufficient if it is not self-contained---if it refers to
  26417. external Guile modules or to extra files. If you want
  26418. @file{configuration.scm} to be self-contained, we recommend that modules
  26419. or files it refers to be part of a channel.
  26420. Besides, provenance meta-data is ``silent'' in the sense that it does
  26421. not change the bits contained in your system, @emph{except for the
  26422. meta-data bits themselves}. Two different OS configurations or sets of
  26423. channels can lead to the same system, bit-for-bit; when
  26424. @code{provenance-service-type} is used, these two systems will have
  26425. different meta-data and thus different store file names, which makes
  26426. comparison less trivial.
  26427. @end quotation
  26428. This service is automatically added to your operating system
  26429. configuration when you use @command{guix system reconfigure},
  26430. @command{guix system init}, or @command{guix deploy}.
  26431. @end defvr
  26432. @node Shepherd Services
  26433. @subsection Shepherd Services
  26434. @cindex shepherd services
  26435. @cindex PID 1
  26436. @cindex init system
  26437. The @code{(gnu services shepherd)} module provides a way to define
  26438. services managed by the GNU@tie{}Shepherd, which is the
  26439. initialization system---the first process that is started when the
  26440. system boots, also known as PID@tie{}1
  26441. (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
  26442. Services in the Shepherd can depend on each other. For instance, the
  26443. SSH daemon may need to be started after the syslog daemon has been
  26444. started, which in turn can only happen once all the file systems have
  26445. been mounted. The simple operating system defined earlier (@pxref{Using
  26446. the Configuration System}) results in a service graph like this:
  26447. @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
  26448. You can actually generate such a graph for any operating system
  26449. definition using the @command{guix system shepherd-graph} command
  26450. (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
  26451. The @code{%shepherd-root-service} is a service object representing
  26452. PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
  26453. by passing it lists of @code{<shepherd-service>} objects.
  26454. @deftp {Data Type} shepherd-service
  26455. The data type representing a service managed by the Shepherd.
  26456. @table @asis
  26457. @item @code{provision}
  26458. This is a list of symbols denoting what the service provides.
  26459. These are the names that may be passed to @command{herd start},
  26460. @command{herd status}, and similar commands (@pxref{Invoking herd,,,
  26461. shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
  26462. @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
  26463. @item @code{requirement} (default: @code{'()})
  26464. List of symbols denoting the Shepherd services this one depends on.
  26465. @cindex one-shot services, for the Shepherd
  26466. @item @code{one-shot?} (default: @code{#f})
  26467. Whether this service is @dfn{one-shot}. One-shot services stop immediately
  26468. after their @code{start} action has completed. @xref{Slots of services,,,
  26469. shepherd, The GNU Shepherd Manual}, for more info.
  26470. @item @code{respawn?} (default: @code{#t})
  26471. Whether to restart the service when it stops, for instance when the
  26472. underlying process dies.
  26473. @item @code{start}
  26474. @itemx @code{stop} (default: @code{#~(const #f)})
  26475. The @code{start} and @code{stop} fields refer to the Shepherd's
  26476. facilities to start and stop processes (@pxref{Service De- and
  26477. Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
  26478. G-expressions that get expanded in the Shepherd configuration file
  26479. (@pxref{G-Expressions}).
  26480. @item @code{actions} (default: @code{'()})
  26481. @cindex actions, of Shepherd services
  26482. This is a list of @code{shepherd-action} objects (see below) defining
  26483. @dfn{actions} supported by the service, in addition to the standard
  26484. @code{start} and @code{stop} actions. Actions listed here become available as
  26485. @command{herd} sub-commands:
  26486. @example
  26487. herd @var{action} @var{service} [@var{arguments}@dots{}]
  26488. @end example
  26489. @item @code{auto-start?} (default: @code{#t})
  26490. Whether this service should be started automatically by the Shepherd. If it
  26491. is @code{#f} the service has to be started manually with @code{herd start}.
  26492. @item @code{documentation}
  26493. A documentation string, as shown when running:
  26494. @example
  26495. herd doc @var{service-name}
  26496. @end example
  26497. where @var{service-name} is one of the symbols in @code{provision}
  26498. (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
  26499. @item @code{modules} (default: @code{%default-modules})
  26500. This is the list of modules that must be in scope when @code{start} and
  26501. @code{stop} are evaluated.
  26502. @end table
  26503. @end deftp
  26504. The example below defines a Shepherd service that spawns
  26505. @command{syslogd}, the system logger from the GNU Networking Utilities
  26506. (@pxref{syslogd invocation, @command{syslogd},, inetutils, GNU
  26507. Inetutils}):
  26508. @example
  26509. (let ((config (plain-file "syslogd.conf" "@dots{}")))
  26510. (shepherd-service
  26511. (documentation "Run the syslog daemon (syslogd).")
  26512. (provision '(syslogd))
  26513. (requirement '(user-processes))
  26514. (start #~(make-forkexec-constructor
  26515. (list #$(file-append inetutils "/libexec/syslogd")
  26516. "--rcfile" #$config)
  26517. #:pid-file "/var/run/syslog.pid"))
  26518. (stop #~(make-kill-destructor))))
  26519. @end example
  26520. Key elements in this example are the @code{start} and @code{stop}
  26521. fields: they are @dfn{staged} code snippets that use the
  26522. @code{make-forkexec-constructor} procedure provided by the Shepherd and
  26523. its dual, @code{make-kill-destructor} (@pxref{Service De- and
  26524. Constructors,,, shepherd, The GNU Shepherd Manual}). The @code{start}
  26525. field will have @command{shepherd} spawn @command{syslogd} with the
  26526. given option; note that we pass @code{config} after @option{--rcfile},
  26527. which is a configuration file declared above (contents of this file are
  26528. omitted). Likewise, the @code{stop} field tells how this service is to
  26529. be stopped; in this case, it is stopped by making the @code{kill} system
  26530. call on its PID@. Code staging is achieved using G-expressions:
  26531. @code{#~} stages code, while @code{#$} ``escapes'' back to host code
  26532. (@pxref{G-Expressions}).
  26533. @deftp {Data Type} shepherd-action
  26534. This is the data type that defines additional actions implemented by a
  26535. Shepherd service (see above).
  26536. @table @code
  26537. @item name
  26538. Symbol naming the action.
  26539. @item documentation
  26540. This is a documentation string for the action. It can be viewed by running:
  26541. @example
  26542. herd doc @var{service} action @var{action}
  26543. @end example
  26544. @item procedure
  26545. This should be a gexp that evaluates to a procedure of at least one argument,
  26546. which is the ``running value'' of the service (@pxref{Slots of services,,,
  26547. shepherd, The GNU Shepherd Manual}).
  26548. @end table
  26549. The following example defines an action called @code{say-hello} that kindly
  26550. greets the user:
  26551. @lisp
  26552. (shepherd-action
  26553. (name 'say-hello)
  26554. (documentation "Say hi!")
  26555. (procedure #~(lambda (running . args)
  26556. (format #t "Hello, friend! arguments: ~s\n"
  26557. args)
  26558. #t)))
  26559. @end lisp
  26560. Assuming this action is added to the @code{example} service, then you can do:
  26561. @example
  26562. # herd say-hello example
  26563. Hello, friend! arguments: ()
  26564. # herd say-hello example a b c
  26565. Hello, friend! arguments: ("a" "b" "c")
  26566. @end example
  26567. This, as you can see, is a fairly sophisticated way to say hello.
  26568. @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
  26569. info on actions.
  26570. @end deftp
  26571. @defvr {Scheme Variable} shepherd-root-service-type
  26572. The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
  26573. This is the service type that extensions target when they want to create
  26574. shepherd services (@pxref{Service Types and Services}, for an example).
  26575. Each extension must pass a list of @code{<shepherd-service>}. Its
  26576. value must be a @code{shepherd-configuration}, as described below.
  26577. @end defvr
  26578. @deftp {Data Type} shepherd-configuration
  26579. This data type represents the Shepherd's configuration.
  26580. @table @code
  26581. @item shepherd (default: @code{shepherd})
  26582. The Shepherd package to use.
  26583. @item services (default: @code{'()})
  26584. A list of @code{<shepherd-service>} to start.
  26585. You should probably use the service extension
  26586. mechanism instead (@pxref{Shepherd Services}).
  26587. @end table
  26588. @end deftp
  26589. The following example specifies the Shepherd package for the operating
  26590. system:
  26591. @lisp
  26592. (operating-system
  26593. ;; ...
  26594. (services (append (list openssh-service-type))
  26595. ;; ...
  26596. %desktop-services)
  26597. ;; ...
  26598. ;; Use own Shepherd package.
  26599. (essential-services
  26600. (modify-services (operating-system-default-essential-services
  26601. this-operating-system)
  26602. (shepherd-root-service-type config => (shepherd-configuration
  26603. (inherit config)
  26604. (shepherd my-shepherd))))))
  26605. @end lisp
  26606. @defvr {Scheme Variable} %shepherd-root-service
  26607. This service represents PID@tie{}1.
  26608. @end defvr
  26609. @node Documentation
  26610. @chapter Documentation
  26611. @cindex documentation, searching for
  26612. @cindex searching for documentation
  26613. @cindex Info, documentation format
  26614. @cindex man pages
  26615. @cindex manual pages
  26616. In most cases packages installed with Guix come with documentation.
  26617. There are two main documentation formats: ``Info'', a browseable
  26618. hypertext format used for GNU software, and ``manual pages'' (or ``man
  26619. pages''), the linear documentation format traditionally found on Unix.
  26620. Info manuals are accessed with the @command{info} command or with Emacs,
  26621. and man pages are accessed using @command{man}.
  26622. You can look for documentation of software installed on your system by
  26623. keyword. For example, the following command searches for information
  26624. about ``TLS'' in Info manuals:
  26625. @example
  26626. $ info -k TLS
  26627. "(emacs)Network Security" -- STARTTLS
  26628. "(emacs)Network Security" -- TLS
  26629. "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
  26630. "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
  26631. @dots{}
  26632. @end example
  26633. @noindent
  26634. The command below searches for the same keyword in man pages:
  26635. @example
  26636. $ man -k TLS
  26637. SSL (7) - OpenSSL SSL/TLS library
  26638. certtool (1) - GnuTLS certificate tool
  26639. @dots {}
  26640. @end example
  26641. These searches are purely local to your computer so you have the
  26642. guarantee that documentation you find corresponds to what you have
  26643. actually installed, you can access it off-line, and your privacy is
  26644. respected.
  26645. Once you have these results, you can view the relevant documentation by
  26646. running, say:
  26647. @example
  26648. $ info "(gnutls)Core TLS API"
  26649. @end example
  26650. @noindent
  26651. or:
  26652. @example
  26653. $ man certtool
  26654. @end example
  26655. Info manuals contain sections and indices as well as hyperlinks like
  26656. those found in Web pages. The @command{info} reader (@pxref{Top, Info
  26657. reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
  26658. (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
  26659. bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
  26660. Introduction}, for an introduction to Info navigation.
  26661. @node Installing Debugging Files
  26662. @chapter Installing Debugging Files
  26663. @cindex debugging files
  26664. Program binaries, as produced by the GCC compilers for instance, are
  26665. typically written in the ELF format, with a section containing
  26666. @dfn{debugging information}. Debugging information is what allows the
  26667. debugger, GDB, to map binary code to source code; it is required to
  26668. debug a compiled program in good conditions.
  26669. This chapter explains how to use separate debug info when packages
  26670. provide it, and how to rebuild packages with debug info when it's
  26671. missing.
  26672. @menu
  26673. * Separate Debug Info:: Installing 'debug' outputs.
  26674. * Rebuilding Debug Info:: Building missing debug info.
  26675. @end menu
  26676. @node Separate Debug Info
  26677. @section Separate Debug Info
  26678. The problem with debugging information is that is takes up a fair amount
  26679. of disk space. For example, debugging information for the GNU C Library
  26680. weighs in at more than 60 MiB@. Thus, as a user, keeping all the
  26681. debugging info of all the installed programs is usually not an option.
  26682. Yet, space savings should not come at the cost of an impediment to
  26683. debugging---especially in the GNU system, which should make it easier
  26684. for users to exert their computing freedom (@pxref{GNU Distribution}).
  26685. Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
  26686. mechanism that allows users to get the best of both worlds: debugging
  26687. information can be stripped from the binaries and stored in separate
  26688. files. GDB is then able to load debugging information from those files,
  26689. when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
  26690. with GDB}).
  26691. The GNU distribution takes advantage of this by storing debugging
  26692. information in the @code{lib/debug} sub-directory of a separate package
  26693. output unimaginatively called @code{debug} (@pxref{Packages with
  26694. Multiple Outputs}). Users can choose to install the @code{debug} output
  26695. of a package when they need it. For instance, the following command
  26696. installs the debugging information for the GNU C Library and for GNU
  26697. Guile:
  26698. @example
  26699. guix install glibc:debug guile:debug
  26700. @end example
  26701. GDB must then be told to look for debug files in the user's profile, by
  26702. setting the @code{debug-file-directory} variable (consider setting it
  26703. from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
  26704. GDB}):
  26705. @example
  26706. (gdb) set debug-file-directory ~/.guix-profile/lib/debug
  26707. @end example
  26708. From there on, GDB will pick up debugging information from the
  26709. @file{.debug} files under @file{~/.guix-profile/lib/debug}.
  26710. In addition, you will most likely want GDB to be able to show the source
  26711. code being debugged. To do that, you will have to unpack the source
  26712. code of the package of interest (obtained with @code{guix build
  26713. --source}, @pxref{Invoking guix build}), and to point GDB to that source
  26714. directory using the @code{directory} command (@pxref{Source Path,
  26715. @code{directory},, gdb, Debugging with GDB}).
  26716. @c XXX: keep me up-to-date
  26717. The @code{debug} output mechanism in Guix is implemented by the
  26718. @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
  26719. opt-in---debugging information is available only for the packages with
  26720. definitions explicitly declaring a @code{debug} output. To check
  26721. whether a package has a @code{debug} output, use @command{guix package
  26722. --list-available} (@pxref{Invoking guix package}).
  26723. Read on for how to deal with packages lacking a @code{debug} output.
  26724. @node Rebuilding Debug Info
  26725. @section Rebuilding Debug Info
  26726. @cindex debugging info, rebuilding
  26727. As we saw above, some packages, but not all, provide debugging info in a
  26728. @code{debug} output. What can you do when debugging info is missing?
  26729. The @option{--with-debug-info} option provides a solution to that: it
  26730. allows you to rebuild the package(s) for which debugging info is
  26731. missing---and only those---and to graft those onto the application
  26732. you're debugging. Thus, while it's not as fast as installing a
  26733. @code{debug} output, it is relatively inexpensive.
  26734. Let's illustrate that. Suppose you're experiencing a bug in Inkscape
  26735. and would like to see what's going on in GLib, a library that's deep
  26736. down in its dependency graph. As it turns out, GLib does not have a
  26737. @code{debug} output and the backtrace GDB shows is all sadness:
  26738. @example
  26739. (gdb) bt
  26740. #0 0x00007ffff5f92190 in g_getenv ()
  26741. from /gnu/store/@dots{}-glib-2.62.6/lib/libglib-2.0.so.0
  26742. #1 0x00007ffff608a7d6 in gobject_init_ctor ()
  26743. from /gnu/store/@dots{}-glib-2.62.6/lib/libgobject-2.0.so.0
  26744. #2 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=1, argv=argv@@entry=0x7fffffffcfd8,
  26745. env=env@@entry=0x7fffffffcfe8) at dl-init.c:72
  26746. #3 0x00007ffff7fe2866 in call_init (env=0x7fffffffcfe8, argv=0x7fffffffcfd8, argc=1, l=<optimized out>)
  26747. at dl-init.c:118
  26748. @end example
  26749. To address that, you install Inkscape linked against a variant GLib that
  26750. contains debug info:
  26751. @example
  26752. guix install inkscape --with-debug-info=glib
  26753. @end example
  26754. This time, debugging will be a whole lot nicer:
  26755. @example
  26756. $ gdb --args sh -c 'exec inkscape'
  26757. @dots{}
  26758. (gdb) b g_getenv
  26759. Function "g_getenv" not defined.
  26760. Make breakpoint pending on future shared library load? (y or [n]) y
  26761. Breakpoint 1 (g_getenv) pending.
  26762. (gdb) r
  26763. Starting program: /gnu/store/@dots{}-profile/bin/sh -c exec\ inkscape
  26764. @dots{}
  26765. (gdb) bt
  26766. #0 g_getenv (variable=variable@@entry=0x7ffff60c7a2e "GOBJECT_DEBUG") at ../glib-2.62.6/glib/genviron.c:252
  26767. #1 0x00007ffff608a7d6 in gobject_init () at ../glib-2.62.6/gobject/gtype.c:4380
  26768. #2 gobject_init_ctor () at ../glib-2.62.6/gobject/gtype.c:4493
  26769. #3 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=3, argv=argv@@entry=0x7fffffffd088,
  26770. env=env@@entry=0x7fffffffd0a8) at dl-init.c:72
  26771. @dots{}
  26772. @end example
  26773. Much better!
  26774. Note that there can be packages for which @option{--with-debug-info}
  26775. will not have the desired effect. @xref{Package Transformation Options,
  26776. @option{--with-debug-info}}, for more information.
  26777. @node Security Updates
  26778. @chapter Security Updates
  26779. @cindex security updates
  26780. @cindex security vulnerabilities
  26781. Occasionally, important security vulnerabilities are discovered in software
  26782. packages and must be patched. Guix developers try hard to keep track of
  26783. known vulnerabilities and to apply fixes as soon as possible in the
  26784. @code{master} branch of Guix (we do not yet provide a ``stable'' branch
  26785. containing only security updates). The @command{guix lint} tool helps
  26786. developers find out about vulnerable versions of software packages in the
  26787. distribution:
  26788. @smallexample
  26789. $ guix lint -c cve
  26790. gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
  26791. gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
  26792. gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
  26793. @dots{}
  26794. @end smallexample
  26795. @xref{Invoking guix lint}, for more information.
  26796. Guix follows a functional
  26797. package management discipline (@pxref{Introduction}), which implies
  26798. that, when a package is changed, @emph{every package that depends on it}
  26799. must be rebuilt. This can significantly slow down the deployment of
  26800. fixes in core packages such as libc or Bash, since basically the whole
  26801. distribution would need to be rebuilt. Using pre-built binaries helps
  26802. (@pxref{Substitutes}), but deployment may still take more time than
  26803. desired.
  26804. @cindex grafts
  26805. To address this, Guix implements @dfn{grafts}, a mechanism that allows
  26806. for fast deployment of critical updates without the costs associated
  26807. with a whole-distribution rebuild. The idea is to rebuild only the
  26808. package that needs to be patched, and then to ``graft'' it onto packages
  26809. explicitly installed by the user and that were previously referring to
  26810. the original package. The cost of grafting is typically very low, and
  26811. order of magnitudes lower than a full rebuild of the dependency chain.
  26812. @cindex replacements of packages, for grafts
  26813. For instance, suppose a security update needs to be applied to Bash.
  26814. Guix developers will provide a package definition for the ``fixed''
  26815. Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
  26816. Packages}). Then, the original package definition is augmented with a
  26817. @code{replacement} field pointing to the package containing the bug fix:
  26818. @lisp
  26819. (define bash
  26820. (package
  26821. (name "bash")
  26822. ;; @dots{}
  26823. (replacement bash-fixed)))
  26824. @end lisp
  26825. From there on, any package depending directly or indirectly on Bash---as
  26826. reported by @command{guix gc --requisites} (@pxref{Invoking guix
  26827. gc})---that is installed is automatically ``rewritten'' to refer to
  26828. @code{bash-fixed} instead of @code{bash}. This grafting process takes
  26829. time proportional to the size of the package, usually less than a
  26830. minute for an ``average'' package on a recent machine. Grafting is
  26831. recursive: when an indirect dependency requires grafting, then grafting
  26832. ``propagates'' up to the package that the user is installing.
  26833. Currently, the length of the name and version of the graft and that of
  26834. the package it replaces (@code{bash-fixed} and @code{bash} in the example
  26835. above) must be equal. This restriction mostly comes from the fact that
  26836. grafting works by patching files, including binary files, directly.
  26837. Other restrictions may apply: for instance, when adding a graft to a
  26838. package providing a shared library, the original shared library and its
  26839. replacement must have the same @code{SONAME} and be binary-compatible.
  26840. The @option{--no-grafts} command-line option allows you to forcefully
  26841. avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
  26842. Thus, the command:
  26843. @example
  26844. guix build bash --no-grafts
  26845. @end example
  26846. @noindent
  26847. returns the store file name of the original Bash, whereas:
  26848. @example
  26849. guix build bash
  26850. @end example
  26851. @noindent
  26852. returns the store file name of the ``fixed'', replacement Bash. This
  26853. allows you to distinguish between the two variants of Bash.
  26854. To verify which Bash your whole profile refers to, you can run
  26855. (@pxref{Invoking guix gc}):
  26856. @example
  26857. guix gc -R `readlink -f ~/.guix-profile` | grep bash
  26858. @end example
  26859. @noindent
  26860. @dots{} and compare the store file names that you get with those above.
  26861. Likewise for a complete Guix system generation:
  26862. @example
  26863. guix gc -R `guix system build my-config.scm` | grep bash
  26864. @end example
  26865. Lastly, to check which Bash running processes are using, you can use the
  26866. @command{lsof} command:
  26867. @example
  26868. lsof | grep /gnu/store/.*bash
  26869. @end example
  26870. @node Bootstrapping
  26871. @chapter Bootstrapping
  26872. @c Adapted from the ELS 2013 paper.
  26873. @cindex bootstrapping
  26874. Bootstrapping in our context refers to how the distribution gets built
  26875. ``from nothing''. Remember that the build environment of a derivation
  26876. contains nothing but its declared inputs (@pxref{Introduction}). So
  26877. there's an obvious chicken-and-egg problem: how does the first package
  26878. get built? How does the first compiler get compiled?
  26879. It is tempting to think of this question as one that only die-hard
  26880. hackers may care about. However, while the answer to that question is
  26881. technical in nature, its implications are wide-ranging. How the
  26882. distribution is bootstrapped defines the extent to which we, as
  26883. individuals and as a collective of users and hackers, can trust the
  26884. software we run. It is a central concern from the standpoint of
  26885. @emph{security} and from a @emph{user freedom} viewpoint.
  26886. @cindex bootstrap binaries
  26887. The GNU system is primarily made of C code, with libc at its core. The
  26888. GNU build system itself assumes the availability of a Bourne shell and
  26889. command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
  26890. `grep'. Furthermore, build programs---programs that run
  26891. @code{./configure}, @code{make}, etc.---are written in Guile Scheme
  26892. (@pxref{Derivations}). Consequently, to be able to build anything at
  26893. all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
  26894. Binutils, libc, and the other packages mentioned above---the
  26895. @dfn{bootstrap binaries}.
  26896. These bootstrap binaries are ``taken for granted'', though we can also
  26897. re-create them if needed (@pxref{Preparing to Use the Bootstrap
  26898. Binaries}).
  26899. @menu
  26900. * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
  26901. * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
  26902. @end menu
  26903. @node Reduced Binary Seed Bootstrap
  26904. @section The Reduced Binary Seed Bootstrap
  26905. Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
  26906. a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
  26907. Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
  26908. GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
  26909. ``taken for granted.''
  26910. Taking the bootstrap binaries for granted means that we consider them to
  26911. be a correct and trustworthy ``seed'' for building the complete system.
  26912. Therein lies a problem: the combined size of these bootstrap binaries is
  26913. about 250MB (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing
  26914. or even inspecting these is next to impossible.
  26915. For @code{i686-linux} and @code{x86_64-linux}, Guix now features a
  26916. ``Reduced Binary Seed'' bootstrap @footnote{We would like to say: ``Full
  26917. Source Bootstrap'' and while we are working towards that goal it would
  26918. be hyperbole to use that term for what we do now.}.
  26919. The Reduced Binary Seed bootstrap removes the most critical tools---from a
  26920. trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
  26921. Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
  26922. linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
  26923. written in Scheme and the Mes C Library, built for TinyCC and for GCC).
  26924. Using these new binary seeds the ``missing'' Binutils, GCC, and the GNU
  26925. C Library are built from source. From here on the more traditional
  26926. bootstrap process resumes. This approach has reduced the bootstrap
  26927. binaries in size to about 145MB in Guix v1.1.
  26928. The next step that Guix has taken is to replace the shell and all its
  26929. utilities with implementations in Guile Scheme, the @emph{Scheme-only
  26930. bootstrap}. Gash (@pxref{Gash,,, gash, The Gash manual}) is a
  26931. POSIX-compatible shell that replaces Bash, and it comes with Gash Utils
  26932. which has minimalist replacements for Awk, the GNU Core Utilities, Grep,
  26933. Gzip, Sed, and Tar. The rest of the bootstrap binary seeds that were
  26934. removed are now built from source.
  26935. Building the GNU System from source is currently only possible by adding
  26936. some historical GNU packages as intermediate steps@footnote{Packages
  26937. such as @code{gcc-2.95.3}, @code{binutils-2.14}, @code{glibc-2.2.5},
  26938. @code{gzip-1.2.4}, @code{tar-1.22}, and some others. For details, see
  26939. @file{gnu/packages/commencement.scm}.}. As Gash and Gash Utils mature,
  26940. and GNU packages become more bootstrappable again (e.g., new releases of
  26941. GNU Sed will also ship as gzipped tarballs again, as alternative to the
  26942. hard to bootstrap @code{xz}-compression), this set of added packages can
  26943. hopefully be reduced again.
  26944. The graph below shows the resulting dependency graph for
  26945. @code{gcc-core-mesboot0}, the bootstrap compiler used for the
  26946. traditional bootstrap of the rest of the Guix System.
  26947. @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
  26948. @image{images/gcc-core-mesboot0-graph,6in,,Dependency graph of gcc-core-mesboot0}
  26949. The only significant binary bootstrap seeds that remain@footnote{
  26950. Ignoring the 68KB @code{mescc-tools}; that will be removed later,
  26951. together with @code{mes}.} are a Scheme intepreter and a Scheme
  26952. compiler: GNU Mes and GNU Guile@footnote{Not shown in this graph are the
  26953. static binaries for @file{bash}, @code{tar}, and @code{xz} that are used
  26954. to get Guile running.}.
  26955. This further reduction has brought down the size of the binary seed to
  26956. about 60MB for @code{i686-linux} and @code{x86_64-linux}.
  26957. Work is ongoing to remove all binary blobs from our free software
  26958. bootstrap stack, working towards a Full Source Bootstrap. Also ongoing
  26959. is work to bring these bootstraps to the @code{arm-linux} and
  26960. @code{aarch64-linux} architectures and to the Hurd.
  26961. If you are interested, join us on @samp{#bootstrappable} on the Freenode
  26962. IRC network or discuss on @email{bug-mes@@gnu.org} or
  26963. @email{gash-devel@@nongnu.org}.
  26964. @node Preparing to Use the Bootstrap Binaries
  26965. @section Preparing to Use the Bootstrap Binaries
  26966. @c As of Emacs 24.3, Info-mode displays the image, but since it's a
  26967. @c large image, it's hard to scroll. Oh well.
  26968. @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
  26969. The figure above shows the very beginning of the dependency graph of the
  26970. distribution, corresponding to the package definitions of the @code{(gnu
  26971. packages bootstrap)} module. A similar figure can be generated with
  26972. @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
  26973. @example
  26974. guix graph -t derivation \
  26975. -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
  26976. | dot -Tps > gcc.ps
  26977. @end example
  26978. or, for the further Reduced Binary Seed bootstrap
  26979. @example
  26980. guix graph -t derivation \
  26981. -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
  26982. | dot -Tps > mes.ps
  26983. @end example
  26984. At this level of detail, things are
  26985. slightly complex. First, Guile itself consists of an ELF executable,
  26986. along with many source and compiled Scheme files that are dynamically
  26987. loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
  26988. tarball shown in this graph. This tarball is part of Guix's ``source''
  26989. distribution, and gets inserted into the store with @code{add-to-store}
  26990. (@pxref{The Store}).
  26991. But how do we write a derivation that unpacks this tarball and adds it
  26992. to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
  26993. derivation---the first one that gets built---uses @code{bash} as its
  26994. builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
  26995. @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
  26996. @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
  26997. the Guix source distribution, whose sole purpose is to allow the Guile
  26998. tarball to be unpacked.
  26999. Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
  27000. Guile that can be used to run subsequent build programs. Its first task
  27001. is to download tarballs containing the other pre-built binaries---this
  27002. is what the @file{.tar.xz.drv} derivations do. Guix modules such as
  27003. @code{ftp-client.scm} are used for this purpose. The
  27004. @code{module-import.drv} derivations import those modules in a directory
  27005. in the store, using the original layout. The
  27006. @code{module-import-compiled.drv} derivations compile those modules, and
  27007. write them in an output directory with the right layout. This
  27008. corresponds to the @code{#:modules} argument of
  27009. @code{build-expression->derivation} (@pxref{Derivations}).
  27010. Finally, the various tarballs are unpacked by the derivations
  27011. @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
  27012. @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
  27013. point we have a working C tool chain.
  27014. @unnumberedsec Building the Build Tools
  27015. Bootstrapping is complete when we have a full tool chain that does not
  27016. depend on the pre-built bootstrap tools discussed above. This
  27017. no-dependency requirement is verified by checking whether the files of
  27018. the final tool chain contain references to the @file{/gnu/store}
  27019. directories of the bootstrap inputs. The process that leads to this
  27020. ``final'' tool chain is described by the package definitions found in
  27021. the @code{(gnu packages commencement)} module.
  27022. The @command{guix graph} command allows us to ``zoom out'' compared to
  27023. the graph above, by looking at the level of package objects instead of
  27024. individual derivations---remember that a package may translate to
  27025. several derivations, typically one derivation to download its source,
  27026. one to build the Guile modules it needs, and one to actually build the
  27027. package from source. The command:
  27028. @example
  27029. guix graph -t bag \
  27030. -e '(@@@@ (gnu packages commencement)
  27031. glibc-final-with-bootstrap-bash)' | xdot -
  27032. @end example
  27033. @noindent
  27034. displays the dependency graph leading to the ``final'' C
  27035. library@footnote{You may notice the @code{glibc-intermediate} label,
  27036. suggesting that it is not @emph{quite} final, but as a good
  27037. approximation, we will consider it final.}, depicted below.
  27038. @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
  27039. @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
  27040. The first tool that gets built with the bootstrap binaries is
  27041. GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
  27042. for all the following packages. From there Findutils and Diffutils get
  27043. built.
  27044. Then come the first-stage Binutils and GCC, built as pseudo cross
  27045. tools---i.e., with @option{--target} equal to @option{--host}. They are
  27046. used to build libc. Thanks to this cross-build trick, this libc is
  27047. guaranteed not to hold any reference to the initial tool chain.
  27048. From there the final Binutils and GCC (not shown above) are built. GCC
  27049. uses @command{ld} from the final Binutils, and links programs against
  27050. the just-built libc. This tool chain is used to build the other
  27051. packages used by Guix and by the GNU Build System: Guile, Bash,
  27052. Coreutils, etc.
  27053. And voilà! At this point we have the complete set of build tools that
  27054. the GNU Build System expects. These are in the @code{%final-inputs}
  27055. variable of the @code{(gnu packages commencement)} module, and are
  27056. implicitly used by any package that uses @code{gnu-build-system}
  27057. (@pxref{Build Systems, @code{gnu-build-system}}).
  27058. @unnumberedsec Building the Bootstrap Binaries
  27059. @cindex bootstrap binaries
  27060. Because the final tool chain does not depend on the bootstrap binaries,
  27061. those rarely need to be updated. Nevertheless, it is useful to have an
  27062. automated way to produce them, should an update occur, and this is what
  27063. the @code{(gnu packages make-bootstrap)} module provides.
  27064. The following command builds the tarballs containing the bootstrap binaries
  27065. (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
  27066. bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
  27067. and Guile, and a tarball containing a mixture of Coreutils and other basic
  27068. command-line tools):
  27069. @example
  27070. guix build bootstrap-tarballs
  27071. @end example
  27072. The generated tarballs are those that should be referred to in the
  27073. @code{(gnu packages bootstrap)} module mentioned at the beginning of
  27074. this section.
  27075. Still here? Then perhaps by now you've started to wonder: when do we
  27076. reach a fixed point? That is an interesting question! The answer is
  27077. unknown, but if you would like to investigate further (and have
  27078. significant computational and storage resources to do so), then let us
  27079. know.
  27080. @unnumberedsec Reducing the Set of Bootstrap Binaries
  27081. Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
  27082. binary code! Why is that a problem? It's a problem because these big chunks
  27083. of binary code are practically non-auditable, which makes it hard to establish
  27084. what source code produced them. Every unauditable binary also leaves us
  27085. vulnerable to compiler backdoors as described by Ken Thompson in the 1984
  27086. paper @emph{Reflections on Trusting Trust}.
  27087. This is mitigated by the fact that our bootstrap binaries were generated
  27088. from an earlier Guix revision. Nevertheless it lacks the level of
  27089. transparency that we get in the rest of the package dependency graph,
  27090. where Guix always gives us a source-to-binary mapping. Thus, our goal
  27091. is to reduce the set of bootstrap binaries to the bare minimum.
  27092. The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
  27093. on-going projects to do that. One of these is about replacing the
  27094. bootstrap GCC with a sequence of assemblers, interpreters, and compilers
  27095. of increasing complexity, which could be built from source starting from
  27096. a simple and auditable assembler.
  27097. Our first major achievement is the replacement of of GCC, the GNU C Library
  27098. and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
  27099. (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
  27100. and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
  27101. bootstrapped yet and thus we inject them as binary seeds. We call this the
  27102. Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
  27103. binaries! Also, it has eliminated the C compiler binary; i686-linux and
  27104. x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
  27105. Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
  27106. also looking at any other bootstrap binaries. Your help is welcome!
  27107. @node Porting
  27108. @chapter Porting to a New Platform
  27109. As discussed above, the GNU distribution is self-contained, and
  27110. self-containment is achieved by relying on pre-built ``bootstrap
  27111. binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
  27112. operating system kernel, CPU architecture, and application binary
  27113. interface (ABI). Thus, to port the distribution to a platform that is
  27114. not yet supported, one must build those bootstrap binaries, and update
  27115. the @code{(gnu packages bootstrap)} module to use them on that platform.
  27116. Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
  27117. When everything goes well, and assuming the GNU tool chain supports the
  27118. target platform, this can be as simple as running a command like this
  27119. one:
  27120. @example
  27121. guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
  27122. @end example
  27123. For this to work, the @code{glibc-dynamic-linker} procedure in
  27124. @code{(gnu packages bootstrap)} must be augmented to return the right
  27125. file name for libc's dynamic linker on that platform; likewise,
  27126. @code{system->linux-architecture} in @code{(gnu packages linux)} must be
  27127. taught about the new platform.
  27128. Once these are built, the @code{(gnu packages bootstrap)} module needs
  27129. to be updated to refer to these binaries on the target platform. That
  27130. is, the hashes and URLs of the bootstrap tarballs for the new platform
  27131. must be added alongside those of the currently supported platforms. The
  27132. bootstrap Guile tarball is treated specially: it is expected to be
  27133. available locally, and @file{gnu/local.mk} has rules to download it for
  27134. the supported architectures; a rule for the new platform must be added
  27135. as well.
  27136. In practice, there may be some complications. First, it may be that the
  27137. extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
  27138. above) is not recognized by all the GNU tools. Typically, glibc
  27139. recognizes some of these, whereas GCC uses an extra @option{--with-abi}
  27140. configure flag (see @code{gcc.scm} for examples of how to handle this).
  27141. Second, some of the required packages could fail to build for that
  27142. platform. Lastly, the generated binaries could be broken for some
  27143. reason.
  27144. @c *********************************************************************
  27145. @include contributing.texi
  27146. @c *********************************************************************
  27147. @node Acknowledgments
  27148. @chapter Acknowledgments
  27149. Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
  27150. which was designed and
  27151. implemented by Eelco Dolstra, with contributions from other people (see
  27152. the @file{nix/AUTHORS} file in Guix). Nix pioneered functional package
  27153. management, and promoted unprecedented features, such as transactional
  27154. package upgrades and rollbacks, per-user profiles, and referentially
  27155. transparent build processes. Without this work, Guix would not exist.
  27156. The Nix-based software distributions, Nixpkgs and NixOS, have also been
  27157. an inspiration for Guix.
  27158. GNU@tie{}Guix itself is a collective work with contributions from a
  27159. number of people. See the @file{AUTHORS} file in Guix for more
  27160. information on these fine people. The @file{THANKS} file lists people
  27161. who have helped by reporting bugs, taking care of the infrastructure,
  27162. providing artwork and themes, making suggestions, and more---thank you!
  27163. @c *********************************************************************
  27164. @node GNU Free Documentation License
  27165. @appendix GNU Free Documentation License
  27166. @cindex license, GNU Free Documentation License
  27167. @include fdl-1.3.texi
  27168. @c *********************************************************************
  27169. @node Concept Index
  27170. @unnumbered Concept Index
  27171. @printindex cp
  27172. @node Programming Index
  27173. @unnumbered Programming Index
  27174. @syncodeindex tp fn
  27175. @syncodeindex vr fn
  27176. @printindex fn
  27177. @bye
  27178. @c Local Variables:
  27179. @c ispell-local-dictionary: "american";
  27180. @c End: