Awesome C
A curated list of C good stuff. This list contains only free software
for code, and sellers who aren't evil for physical resources.
This is released under a Creative Commons-Attribution-ShareAlike license,
version 4. You can find its text in the LICENSE file.
This project is part of Peers - a community for growing our
freedom. Support us today!
An important note: This project does not index anything C++-related; only
pure C stuff is considered.
Note for contributors: If you want to make a pull request, please read
CONTRIBUTING.md first.
Contents
AI
This includes such things as computer vision, neural nets, machine learning, and
other such things. Basically, if your university calls it AI, it lives here.
- ccv - C-based/Cached/Core Computer Vision library; modern computer
vision. 3-clause BSD.
- FANN - Fast Artifical Neural Network library; an implementation of
neural networks. GNU GPLv2.1 only.
- Genann - A simple ANN in C89, without additional dependencies. zlib.
- libdeep - A deep learning library. 3-clause BSD.
Build Systems
These are tools to automate the building and testing of projects in C.
- aimake - A build tool designed to avoid complex
configurations. GNU GPLv3 or later.
- Autoconf - An extensible package of M4 macros that produce shell
scripts to automatically configure software source code packages. Part of the
Autotools. GNU GPLv3 or later.
- Automake - A tool for automatically generating
Makefile.in
files
compliant with the GNU Coding Standards. Requires the use of Autoconf. Part of
the Autotools. GNU GPLv3 or later.
- fab - A build system that helps build optimally every
time. GNU GPLv3 only.
- GNU Make - A tool which controls the generation of executables and other
non-source files of a program. GNU GPLv3 or later.
- Jam - A build system, designed to be easier than make. Understands C
build rules implicitly. Jam License.
- Libtool - A generic library support script. Part of the
Autotools. GNU GPLv3 or later.
- Meson - An extremely fast, user-friendly build system. Based on Ninja. Apache2.0.
- Premake - A command-line utility which reads a scripted definition of a
software project and uses it to generate project files for Visual Studio and
GNU Make. Other targets are also being worked on. 3-clause BSD.
- tup - A very fast, file-based, cross-platform build
system. GNU GPLv2.1 only.
- zproject - A project generator and build system support. MPLv2.0
Compilers
This section also includes compiler-related and compilation-related tooling.
- ccache - A compiler cache designed to speed up recompilation. GNU
GPLv3 or later.
- Clang - A compiler for LLVM. Supports C11. NCSA.
- distcc - A program to allow builds to be distributed among several
machines. GNU GPLv2.1 or later.
- GCC - Provides a C compiler as part of its compiler set. Supports
C11. GNU GPLv3 or later.
- PCC - A venerable compiler. Supports C99. Various licenses, all free.
Compression
Concurrency and Parallelism
- cchan - A small library for channel constructs for inter-thread
communication. Public domain.
- cf4ocl - The C Framework for OpenCL; a cross-platform object-oriented
framework for developing and benchmarking OpenCL.
projects. GNU LGPLv3 only (library), GNU GPLv3 or later (other
code).
- checkedthreads - No race condition goes unnoticed! A simple library for
parallelism, with built-in checking for race conditions. FreeBSD.
- ck - Concurrency primitives, safe memory reclamation mechanisms and
non-blocking data structures. FreeBSD.
- libconcurrent - Concurrent programming library, using coroutines, for
C11. zlip.
- libdill - A library which makes structured concurrent programming
easy. X11.
- libhl - A library implementing a thread-safe API to manage a range of data
structures. Also provides some supporting functions and structures for
concurrent and lockfree programming. GNU LGPLv3 only.
- liburcu - A data synchronization library, which scales linearly with the
number of cores. GNU LGPLv2.1 or later.
- mill - Go-style concurrency. X11.
- MPICH - Another implementation of MPI. MPICH licence.
- OpenMP - A set of pragmas designed to allow for easy parallelization of
code. Standard (licensing not applicable).
- OpenMPI - A message passing interface implementation. 3-clause BSD.
- pal - An optimized library for maths, parallel processing and data
movement. Apache2.0.
- PETSc - A suite of data structures and routines for scalable parallel
solution of scientific applications modelled by partial differential
equations. FreeBSD.
- pth - A portable implementation for non-preemptive priority-based
scheduling for multiple threads of execution. GNU GPLv3 or later.
- pthreads - The POSIX thread library. Standard (no license applicable).
- TinyCThread - A portable, small implementation of the C11 threads
API. zlib.
Crypto
This is mostly library implementations of well-known cryptographic algorithms or
protocols.
Database
This lists databases and data stores with C APIs.
- BerkeleyDB - A library for a high-performance embedded database for
key-value data. GNU AGPLv3 only.
- Hiredis - A minimalistic client library for Redis. 3-clause BSD.
- libmongoc - A high-performance client library for MongoDB. Apache2.0.
- LMDB - An ultra-fast, ultra-compact key-value embedded data store. newOpenLDAP.
- MariaDB - A robust, scalable and reliable SQL server, designed to be a
drop-in replacement for MySQL. 3-clause BSD.
- PostgreSQL - A powerful object-relational database system. PostgreSQL licence.
- recutils - A set of tools and a library for accessing human-editable,
plaintext database files called recfiles. GNU GPLv3 or later.
- Redis - An advanced key-value store. 3-clause BSD.
- sophia - A modern, embeddable key-value database. FreeBSD.
- SQLite - A self-contained, serverless, zero-configuration, transactional
SQL database engine. Public domain.
- UnQLite - A self-contained, serverless, zero-configuration,
transactional NoSQL engine. FreeBSD.
Debugging
Because we all have to do it sometimes. This includes various tools for making
debugging easier or better, as well as libraries or code that allows better
debugging work.
- C-Reduce - A tool that takes a large C file with a property of interest
and automatically produces a much smaller C file that has the same
property. Intended to help create minimal bug-demonstrating cases in complex
code. 3-clause BSD.
- CBMC - C Bounded Model Checker; a tool for verification of array
bounds, pointer safety and user-specified assertions. Original BSD.
- cflow - Analyzes a collection of source files and prints a graph
charting control flow in the program. GNU GPLv3 or later.
- Complexity - A tool for measuring the complexity of source
code. GNU GPLv3 or later.
- CScout - A source code analyzer and refactoring browser for C
programs. GNU GPLv3 only.
- DDD - A graphical front-end for a range of command-line
debuggers. GNU GPLv3 or later.
- debug - A one-header library for easier 'printf debugging'.
Expat.
- GDB - The GNU Project debugger. GNU GPLv3 or later.
- lldb - The LLVM debugger. NCSA.
- rr - A debugger that records non-deterministic executions to allow for
deterministic debugging. FreeBSD.
- Valgrind - A range of dynamic analysis tools, including a leak
checker. GNU GPLv2.1 only.
Documentation Generation
- Cxref - Generates documentation in either LaTeX, HTML, RTF or
SGML. GNU GPLv2.1 only.
- DocOnce - A modestly-tagged markup language that can be used to
generate a range of formats. 3-clause BSD.
- Doxygen - The de-facto standard tool for generating documentation from
annotated sources. Can generate a large range of formats. GNU GPLv2.1
only.
- GTK-Doc - A tool for generating documentation from annotated
sources. Has support for the Autotools. GNU GPLv2.1 only
(code), GNU FDL1.1 only (documentation).
Editors
These are specifically fancier, IDE-type editors. If you want a programmer's
text editor, look elsewhere. Besides, whatever choice you make most likely
supports C anyway.
Frameworks
This section has big libraries that provide data structures and other stuff you
expect of a 'modern' standard library.
- APR - Apache Portable Runtime; another library of cross-platform utility
functions. Apache2.0.
- C Algorithms - A collection of common algorithms and data structures. ISC.
- Collections-C - A library of generic data structures. GNU LGPLv3
or later.
- CPL - The Common Pipeline Library; a set of libraries designed to be a
comprehensive, efficient and robust software toolkit. GNU GPLv2.1 only.
- EFL - A large collection of useful data structures and
functions. Various licenses, all free.
- GLib - A library of utility functions and structures, designed to be
portable, efficient and powerful. GNU LGPLv2.1 only.
- GIO - A modern and easy-to-use VFS API. GNU LGPLv2.1 only.
- GObject - An object-oriented system and object model. GNU LGPLv2.1 only.
- libcork - Utility functions and structures, designed for
resource-constrained systems. Can be embedded. 3-clause BSD.
- libnih - A lightweight library of functions and
structures. GNU GPLv2.1 only.
- libU - A small library of basic utilities, including memory allocation,
string manipulation and logging. 3-clause BSD.
- PBL - A large library of utilities, featuring data structures, among
other things. GNU LGPLv2.1 or later (library), GNU GPLv2.1 or later
(test code).
- qlibc - A simple and powerful library, designed as a replacement for
GLib while focusing on being small and light. qLib license (similar
to FreeBSD).
- stb - A range of single-file libraries. Public domain.
- TBOX - A multi-platform library with a large number of
capabilities. GNU LGPLv2.1 or later.
Game Programming
Engines
These are provided as examples of C game programming code.
Resources
These are libraries of all sorts that are useful for game programming.
- Allegro - A cross-platform, video game development and multimedia
library. zlib.
- Chipmunk2D - A fast and lightweight 2D game physics library. Expat.
- CSFML - A binding for SFML. zlib.
- Epoxy - A library for handling OpenGL function pointer management. Expat.
- FreeGLUT - An alternative to the OpenGL Utility Toolkit. Allows the
creation and management of windows with OpenGL contexts. X11.
- GLFW - A multi-platform library for creating windows with OpenGL
contexts. zlib.
- kazmath - A maths library for games. FreeBSD.
- libao - A cross-platform audio library with a wide variety of
outputs. GNU GPLv2.1 or later.
- RetroArch - The reference frontend for libretro. GNU GPLv3
only.
- SDL2 - A cross-platform library designed to provide low-level access to
audio, keyboard, mouse, joystick and graphics hardware via OpenGL. zlib.
- sdl-gpu - A library for high-performance, modern 2D graphics. Based on
SDL. Expat.
- SIGIL - Sound, Input and Graphics Integration Library; a simple
alternative to other libraries for doing all those things. Various licenses,
all free.
Generic Programming
- klib - Small and lightweight implementations of common algorithms and
data structures. Expat.
- SGLIB - A simple generic library. Any OSI-approved license.
Graphics
Graphical User Interface
These are specifically widget toolkits, or things meant to be used in a
similar way to them.
JSON
- cJSON - Ultra-lightweight JSON parser. Expat.
- Jansson - A library for encoding, decoding and manipulating JSON. Expat.
- jsmn - A minimalistic JSON parser. Expat.
- jfes - A simple JSON engine without any dependencies. Expat.
- json-c - A library for working with JSON. Expat.
- WJElement - Advanced JSON manipulation library, with support for JSON
Schema. LGPL, any version.
- YAJL - A fast streaming JSON parser library. ISC
Learning, Reference and Tutorials
This is a list of resources for learning C programming in general, or something
useful relating to C programming.
Reference resources online
Beginner resources online
Intermediate resources online
Advanced resources online
Online self-study courses
Reference books
Beginner books
Intermediate books
Advanced books
Memory Management
Whether a different, faster malloc
or outright garbage collection, anything
to do with managing C memory lives here.
Multimedia
- FFMPEG - A complete, cross-platform solution to record, convert and
stream audio and video. GNU LGPLv2.1 or later, with some parts
under GNU GPLv2.1 or later.
- GStreamer - A framework for audio and visual media. GNU LGPLv2.1
only.
- libmpv - A music-playing library. Compile with
./waf configure
--disable-cplayer --enable-libmpv-shared
to not have the music
player. GNU GPLv2.1 or later.
- libsndfile - A library for reading and writing sound files. Supports
many formats. GNU LGPLv2.1 only or GNU LGPLv3 only.
- libsoundio - A library for cross-platform, real-time audio input and
output. Has a range of back-ends. Expat.
- lodepng - A simple PNG image decoder and encoder, requiring no other
dependencies. 3-clause BSD.
Networking and Internet
- asnlc - A compiler of ASN.1 specifications into C source code. FreeBSD.
- CHL - C Hypertext Library - A library for writing web applications in
C. GNU GPLv3 only.
- czmq - A high-level binding for ZeroMQ. MPLv2.0
- GNU adns - An advanced, easy-to-use, asynch-capable DNS client library
and utilities. GNU GPLv3 or later.
- gumbo-parser - An HTML5 parsing library in C99. Apache2.0.
- http-parser - An HTTP request/response parser. Expat.
- ldns - A library to simplify DNS programming. 3-clause BSD.
- libcurl - A client-side URL transfer library, supporting a wide range of
formats. curl license.
- LibEtPan - A mail library providing an efficient network for IMAP,
SMTP, POP and NNTP. 3-clause BSD.
- libev - Yet another event loop. FreeBSD.
- libevent - An event loop replacement for network servers. 3-clause BSD.
- libhttpd - A library to add basic web server capabilities to an
application or embedded device. GNU GPLv2 only.
- libidn - An implementation of the Stringprep, Punycode and IDNA
specifications. GNU GPLv3 or later.
- libmicrohttpd - A small library that makes it easy to run an HTTP
server as part of another application. GNU LGPLv2.1 or later.
- libonion - HTTP server library, designed to be easy to
use. Apache2.0.
- libquickmail - A library intended to give developers a way to send
email from their applications. Supports multiple To/Cc/Bcc recipients and
attachments without size limits. GNU GPLv3 or later.
- libsoup - A GNOME HTTP client/server library. Uses
GObject. GNU LGPLv2.1 only.
- LibVNCServer - Cross-platform libraries to implement VNC server and/or
client functionality. GNU GPLv2.1 or later.
- lwan - An experimental, scalable, high-performance HTTP
server. GNU GPLv2.1 only.
- mongoose - Embedded web server. GNU GPLv2.1 only.
- nanomsg - A C-based implementation of ZeroMQ. Expat.
- oSip - A SIP implementation without additional
dependencies. GNU LGPLv2.1 or later.
- socket99 - A C99 wrapper for the BSD sockets API. ISC.
- twitc - A mini library for interacting with the Twitter OAuth API. Expat.
- trezor-crypto - Heavily-optimized crypto algorithms for embedded
devices. Expat.
- Wslay - A WebSocket library. Implements version 13 of the WebSocket
protocol, as described in RFC 6455. Expat.
- zyre - A framework for proximity-based peer-to-peer applications. MPLv2.0.
Web Frameworks
- balde - A microframework based on GLib. GNU LGPLv2.1 only.
- KLone - A fully-featured, multi-platform, web application development
framework, targeted especially at embedded systems and
appliances. 3-clause BSD.
- Kore - An easy-to-use web application framework for writing scalable
web APIs in C. ISC.
Numerical
- apophenia - A library for statistical and scientific
computing. GNU GPLv2.1 only.
- ATLAS - Automatically Tuned Linear Algebra Software. 3-clause BSD.
- BLAS - Basic Linear Algebra Subprograms; a set of routines that provide
vector and matrix operations. BLAS license.
- clBLAS - BLAS functions written in OpenCL. Apache2.0.
- Cuba - A library for multidimensional numerical
integration. GNU LGPLv3 only.
- FFTW - The Fastest Fourier Transform in the West; a highly-optimized
fast Fourier transform routine. GNU GPLv2.1 or later.
- FLINT - Fast Library for Number Theory; a library supporting arithmetic
with numbers, polynomials, power series and matrices, among
others. GNU GPLv2.1 or later.
- GLPK - GNU Linear Programming Kit; a package designed for solving
large-scale linear programming, mixed integer programming and other related
problems. GNU GPLv3 or later.
- GMP - GNU Multple Precision Arithmetic Library; a library for
arbitrary-precision arithmetic. Dual-licensed GNU GPLv2.1 only
and GNU LGPLv3 only.
- GNU MPC - A library for complex number arithmetic. GNU LGPLv3 or later.
- GNU MPFR - A library for arbitrary-precision floating-point
arithmetic. GNU LGPLv3 or later (most recent
versions), GNU LGPLv2.1 or later (until version 2.4.x).
- GNU MPRIA - A portable mathematics library for multi-precision rational
interval arithmetic. GNU GPLv3 or later.
- GSL - The GNU Scientific Library; a sophisticated numerical
library. GNU GPLv3 only.
- KISS FFT - A very simple fast Fourier transform library. 3-clause BSD.
- LAPACKE - An interface to LAPACK. 3-clause BSD.
- LibTomMath - A portable, number-theoretic, multiple-precision integer
library. Supports algebra, digit manipulation, modular reductions, and various
number-theoretic routines. Public domain.
- LibTomPoly - A polynomial-related maths library. Public domain.
- PARI/GP - A computer algebra system for number theory; includes a
compiler to C. GNU GPLv2.1 or later.
- PETSc - A suite of data structures and routines for scalable parallel
solution of scientific applications modelled by partial differential
equations. FreeBSD.
- SCS - Splitting Conic Solver; a numerical optimization package for
solving large-scale convex cone problems. Expat.
- SLEPc - A software library for the solution of large, sparse eigenvalue
problems on parallel computers. GNU LGPLv3 only.
- TomsFastMath - A set of assembly-level-optimized maths operations,
suitable for cryptographic use. Public domain.
- Yeppp! - Very fast, SIMD-optimized mathematical library. 3-clause BSD.
Profiling
- gperftools - A collection of utilities for measuring and improving
performance. 3-clause BSD.
- gprof - A performance analysis tool. Part of GNU binutils.
GNU GPLv3 or later.
- OProfile - A statistical profiler for GNU/Linux. Can profile any code
(including the kernel!) with low overhead and without recompilation. GNU
GPLv2.1 only.
Regex
"Some people, when confronted with a problem, think 'I know, I'll use regular
expressions'. Now they have two problems." - Jamie Zawinski.
- PCRE - An implementation of regexes identical to that of
Perl 5. 3-clause BSD.
- SLRE - Super Light Regular Expression library; a very small
implementation of a subset of Perl regex syntax. GNU GPLv2.1 only.
- TRE - A POSIX-compliant, feature-full regex library. FreeBSD.
Serialization
- binn - A binary serialization format, meant to be compact, fast and
easy-to-use. Apache2.0.
- c-capnproto - An implementation of the Cap'n Proto serialization
protocol. Expat.
- cmp - An implementation of the MessagePack serialization
protocol. Expat.
- libavro - An implementation of the Avro data serialization system. Apache2.0.
- mpack - Another implementation of the MessagePack serialization
protocol. Expat.
- protobuf-c - An implementation of Google Protocol Buffer. FreeBSD.
- xdr - External Data Representation; a standard for data
serialization. Standard (no license applicable).
Source Code Collections
This contains collections of small source code. If you want something big and
integrated, check the Frameworks section.
- CCAN - Modelled after Perl's CPAN, this is a big collection of code
that does stuff. The full list is here. Various licenses, all free.
- clib - Something of a package manager. Comes with
a bunch of libraries of its own. Expat.
- gnulib - A collection of common GNU code. Various licenses, all free.
- libdjb - A collection of libraries doing various things. (Apparently)
public domain.
- par - A bunch of single-file libraries. Expat.
Standard Libraries
This contains standard C libraries.
String Manipulation
- bstrlib - The Better String Library. Dual-licensed
under 3-clause BSD or GNU GPLv2.1 only.
- ICU - International Components for Unicode; a library for Unicode
support. ICU license.
- libunistring - A library for manipulating Unicode
strings. GNU LGPLv3 only.
- libgiconv - A text conversion library. GNU LGPLv2.1 only
(library), GNU GPLv3 only (iconv program).
- librope - A UTF-8 rope ('heavy' string) library. Expat.
- SDS - Simple Dynamic Strings; a library for handling strings in a
simpler way, but one that is compatible with normal C string
functions. Available via clib. FreeBSD.
- utf8.h - Single-header UTF-8 library, designed to mimic C-style string
functions. Public domain.
- utf8proc - A library for processing UTF-8 data. Expat.
Testing
Text Editor Extensions
While practically any decent programmer's text editor supports C, there are some
extensions that make it more pleasant. This is categorized by editor.
Emacs
- CEDET - Collection of Emacs Development Environment Tools; designed to
provide IDE-like features to Emacs. Built-in. GNU GPLv3 or later.
- Flycheck - Modern syntax checking. For C, it can use either GCC or
Clang as a back-end. GNU GPLv3 or later.
- YASnippet - A template system, with C templates for common code
snippets. GNU GPLv3 or later.
Neovim/Vim
Tools
This is a list of useful programs to help you write and debug C code which are
not editors, libraries or compilers.
- Artistic Style - A fast and small automatic source code formatter that
supports C. GNU LGPLv3 only.
- address-sanitizer - A fast memory error detector. Apache2.0.
- biicode - A modern dependency manager. Expat.
- c - Compile and execute C "scripts" in one go on the command line. Also
has shebang support. Expat.
- c99sh - Run C files using hash-bang. FreeBSD.
- cdecl - An online service to translate C declarations into English and
vice versa. Public domain.
- cinclude2dot - Graphs include dependencies in a project using
Graphviz. Any GNU GPL version (due to underspecification in the file).
- Glade - A RAD tool to enable quick development of GTK+
GUIs. GNU GPLv2.1 only.
- GMSL - GNU Make Standard Library; a collection of additional
functionality for GNU Make. 3-clause BSD.
- GNU Global - A source code tagging tool. GNU GPLv3 only.
- GPP - A general-purpose preprocessor. More versatile than the C
preprocessor, but more flexible than m4. GNU LGPLv3 or later.
- Highlight - Converts source code to formatted text with nice
highlighting. GNU GPLv3 only.
- include-what-you-use - Helps find unecessary inclusions and make
suggestions for fixing them. Based on LLVM/Clang (and only works with
it). NCSA.
- indent - Formats C source code automatically to make it easier to
read. Also converts from one style of source to another. GNU GPLv3 or
later.
- qo - A build system that works without a separate config file. Expat.
- unifdef - Removes #ifdef and #if directives with their delimited text
without touching any other part of the file. 3-clause BSD
and FreeBSD.
Utilities
This is a 'catch-all' category for anything that doesn't fit well anywhere else.
- ApeTagLibs - A library for working with APEv2 tags. Expat.
- argparse - A command-line argument parsing library, inspired by
Python's argparse module. Expat.
- attr - Commands for manipulating filesystem extended
attributes. GNU GPLv2.1 or later.
- bfd - A library for manipulating binary object files. Part of GNU
binutils. GNU GPLv3 or later.
- CException - An implementation of exceptions. Expat.
- CommonMark - An implementation of the CommonMark spec.
Variety of licenses, all free.
- CRIU - Checkpoint/Restore In Userspace; a software tool (with a C API)
for 'freezing' a running application to disk, then restoring
it. GNU GPLv2.1 only and GNU LGPLv2.1 only (depending on file -
check the code for details).
- D-Bus - A simple way for applications to talk to one
another. AFLv2.1 or GNU GPLv2.1 or later.
- Discount - A simple implementation of a Markdown parser. 3-clause BSD.
- dlx - An implementation of Knuth's Algorithm X, with example
solvers. GNU GPLv3 or later.
- docopt.c - An implementation of a command-line option parser. Expat.
- dyncall - Another foreign function interface library. Expat.
- Firm - A library that provides a graph-based intermediate
representation, optimizations and assembly code generation suitable for use in
compilers. Comes with an example C front-end under the same
license. GNU LGPLv2.1 only.
- gjrand - A library of random-number generation
routines. GNU GPLv2.1 only or GNU GPLv3 only (user's choice).
- GNU FreeIPMI - An in-band and out-of-band IPMI
implementation. GNU GPLv3 only.
- GNU gperf - A perfect hash function generator, given a list of
strings. Outputs C code. GNU GPLv3 or later.
- GNU Libffcall - A collection of libraries for building foreign function
interfaces. GNU GPLv3 or later.
- hammer - Parser combinators for binary formats. GNU GPLv2.1 only.
- Hoedown - A fully-standards-compliant, extension-supporting, UTF-8
aware, fast Markdown parser. Expat.
- iniparser - A parser for .ini files. Expat.
- jwHash - A fast hashtable implementation. Apache2.0.
- kdtree - A simple library for working with KD-trees. 3-clause BSD.
- Kitsune - An efficient, general-purpose framework for dynamic software
updating. GNU LGPLv3 or later.
- libavl - A library containing a range of self-balancing binary
trees. GNU GPLv3 or later.
- libbson - A BSON utility library. Apache2.0.
- libCello - A library introducing higher-level programming to
C. 3-clause BSD.
- libcmark - A library for parsing the CommonMark dialect of
Markdown. FreeBSD.
- libcox - A library which permits cross-platform system calls and
standard utilities across different operating systems. FreeBSD.
- libcsv - A simple, streaming CSV parser. GNU LGPLv2.1 or later.
- libffi - A portable foreign-function interface library. Expat.
- libgit2 - Pure C implementation of Git. GNU GPL2 only, with a linking exception.
- libgss - Generic Security Service. GNU GPLv3 or later.
- liblfds - A portable lock-free data structure library. Public domain
(more exactly, whatever license you want).
- libimobiledevice - A cross-platform protocol library to communicate
with iThings. GNU LGPLv2.1 or later (library), GNU GPLv2.1 or later
(tools).
- libnfc - A platform-independent Near-Field Communication
library. GNU LGPLv3 only.
- libPhenom - An eventing framework for building high-scalability and
high-performance systems. Apache2.0.
- libpostal - A library for parsing and normalization of street addresses
around the world. Powered by statistical NLP and open geo data. Expat.
- libtrading - An implementation of network protocols for communicating
with exchanges, dark pools and other trading venues. Supports FIX, FIX/FAST
and many proprietary protocols. FreeBSD.
- libucl - A universal configuration library parser. FreeBSD.
- libuv - Cross-platform asynchronous I/O. Expat.
- libYAML - A YAML 1.1 parser and emitter. Expat.
- libxo - Allows an application to generate plain text, XML, JSON and
HTML output using a common set of function calls. The application decides at
runtime what output style should be produced. FreeBSD.
- mpc - A parser combinator library. FreeBSD.
- ncurses - Coloured terminal UI library. GNU GPLv3 or later.
- nope.c - An ultra-light software platform for scalable server-side and
networking applications (think node.js for C programmers). GNU GPLv2.1
only.
- pbc - A protocol buffers library. Expat.
- progressbar - An easy-to-use library for displaying text progress bars.
3-clause BSD.
- rabbitmq-c - A client library for RabbitMQ. Expat.
- Ragel - A DSL for state machines that compiles to C. GNU GPLv2.1 only.
- sort - A collection of sorting routines, which type-specialize at
compile-time with a user-defined type. Expat.
- termbox - A library for writing text-based interfaces. Expat.
- tinyexpr - A tiny recursive-descent parser, compiler and evaluation
engine for simple mathematical expressions. 3-clause BSD.
- tpl - A small binary serialization library. Expat.
- Tulip Indicators - A library of functions for technical analysis of
financial data. GNU LGPLv3 or later.
- uthash - A hash table implementation, allowing existing structures to
be stored in a hash table easily. 1-clause BSD.
- vector.h - A header library for typed lists. Expat.
- Viola - A simplification of libCello. Expat.
- XLSX I/O - A cross-platform library for reading and writing .xlsx
files. Expat.
- ZeroMQ - A distributed messaging protocol
implementation. GNU LGPLv3 with static linking exception only.
- zlog - A reliable, pure C logging library. GNU LGPLv2.1 only.
- zproto - A protocol framework for ZeroMQ. Expat.
Windows Environments
This is a list of technologies designed to bring Windows into the 21st century
with respect to support for C.
- Cygwin - Designed to emulate a POSIX-compatible environment extensively
under Windows. Various licenses, all free.
- MinGW-w64 - A minimalist environment for C development on Windows with
64 bit support. Various licenses, all free.
- MSYS2 - Minimal SYStem 2; aims to provide support for a POSIX
environment on Windows, with a package manager based on Arch Linux's
pacman. Packages have individual licenses, otherwise, as MinGW and Cygwin.
XML
"XML is crap. Really. There are no excuses. XML is nasty to parse for humans,
and it's a disaster to parse even for computers. There's just no reason for
that horrible crap to exist." - Linus Torvalds