A list of open source C libraries

The objective of this page is to build a comprehensible list of open source C libraries, so that when one needs an implementation of particular functionality, one need not waste time searching on Google.

If you know a library that might be useful to others, please add a link to it here. There are no restrictions on what can be included except that it must be possible to download the source of the library.

The page is provided 'as is' - with the hope of being useful, but without any warranties. Outdated, misleading or wrong links might appear here. If you've noticed one of these, it would be great if you fixed the error.

Operating system

Access control

• acl
• apparmor

Extended attributes

• attr

Graphic user interface

• IUP
• tiny file dialogs -  a single C cross-platform file (no init, no main loop, 6 modal function calls)

Gtk+ widgets

• gtk+
• appmenu-gtk
• ghex
• gtkspell
• gtksourceview
• gtkhotkey
• gucharmap
• goocanvas
• webkitgtk

Microsoft Excel

• libxlsxwriter
• xlsx_drone

Audio

Codecs

• aften
• faad2
• wavpack

Infrastructure

• alsa-lib
• portaudio

CD

• cdparanoia

Speech synthesis

• espeak
• flite

Video

Codecs

• schroedinger
• video4linux

Files

• gmime

Maths

• gsl

Integer Multi-Dimensional Interpolation

• argyll

Linear algebra

• atlas
• blas
• eigen

Finance

• ta-lib

FFT

• fftw3

Multiprecision

• gmp

Signal Processing

• liquid-dsp
• vsipl
• vsipl++

Graphics

• cairo
• babl
• SDL (Simple DirectMedia Layer) -  a library for input, audio, drawing and much more supported by many platforms.
• SIGIL (Sound, Input, and Graphics Integration Library)
• allegro 5 (Multimedia Library) -  a cross-platform library mainly aimed at video game and multimedia programming.

Interprocess

• gdbus
• dbus
• dee

Databases

• berkeley db
• lmdb

Configuration

• libconfig
• libconfini

Environment

• libXDGdirs

Communications

• libcurl
• libmicrohttpd
• libsagui
• gsoap
• zeromq
• MQTT-C -  Github URL (MIT License)
• KCP -  A fast and reliable ARQ protocol that helps applications to reduce network latency. (MIT License)
• UCX -  Unified Communication X (UCX) provides an optimized communication layer for Message Passing (MPI), Shared Memory (PGAS) and RPC/data-centric applications. (BSD3 License)

Compression

• bzip2
• zlib

Concurrency

• ck
• MutexGear -  Mutex-only synchronization (wheel, rwlock, work queues). (The MutexGear Library License)

libc

• eglibc

Data types

• bstrlib
• datastd
• str -  Yet another string library for C language.

XML

• expat
• gsoap

Javascript

• gjs

Metrics

• edlib

Object oriented programming

• Cello

Web Frontend

• cgit

See also

C++ documentation for Non-ANSI/ISO Libraries