Then "C language resources of
"http://bbs.csdn.net/topics/391888368
String handling
? Bstrlib - better string processing library, dual license, 3 - clause BSD or GNU GPL2.1,
? ICU - International Components for Unicode; Unicode support library, ICU license,
? Libunistring - handle Unicode string C library, GNU LGPL3,
? Libgiconv - text conversion library, GNU LGPL2.1 (library), GNU GPL3 (code conversion program),
? SDS - Simple Dynamic Strings; A simple way of dealing with the C string library, and compatible with the standard C string functions, can be used by clib, FreeBSD,
? Shoco - a small text compressors, the Expat,
? Smaz - an efficient compression string library, 3 - clause BSD.

The test
? CHEAT - a very simple unit test framework, FreeBSD,
? Check - a C unit testing framework, the GNU LGPL2.1,
? CMock - a mock/C stub generator,
? Cmocka - a unit testing framework, support the mock object Apache2.0,
? Criterion - a KISS style, non-invasive C testing framework, the Expat
? CUnit - another C unit testing framework, the GNU LGPL2.0,
? Minunit - tiny C unit testing framework, the Expat,
? Unity - a simple C unit testing framework, the Expat,

Text editor extension
In almost any decent programmer text editor support C, there are some extensions, let the editor is more pleasant, below is according to the editor points directory,
Emacs
? CEDET - a Collection of Emacs Development Environment Tools; To Emacs provides a similar to the characteristics of the IDE, is built, the GNU GPL3 or higher,
? Flycheck - modern syntax checking, for C, it can use GCC or Clang as backend, GNU GPL3 or higher,
? Yasnippet - a template system, support general C code snippet, GNU GPL3 or higher,

Vim
? Syntastic - syntax checking and language analysis, Do What The Fuck You Want To license,
? YouCompleteMe - a Vim code completion engine, the GNU GPL3,

Tool
The following is a list of practical application, including help you write and debug C code library or compiler, not including the editor,
? Adlint - a static analyzer, support C89 standard and some C99 standard completely, GNU GPL3 or higher,
? Artistic Style - a small and fast automation support C code formatting tools, GNU LGPL3,
? Address - sanitizer - a quick memory error detector, Apache2.0,
? Biicode - a modern C depend on the manager, the Expat,
? C - compile and execute c script on the command line, also support the shebang, the Expat,
? C99sh - use hash - bang run C file, FreeBSD,
? Abbreviated as CBMC C Bounded Model Checker. A pointer to check the array bounds, security and user custom assertions of tools, the Original BSD,
? Cdecl - an online service, can put C statement translated into English, the reverse can also, the public domain,
? Cinclude2dot - use Graphviz image in C program contains dependencies, any version of the GNU GPL (according to the requirements of the file)
? Complexity - a measurement tool of C code Complexity, GNU GPL3 or higher,
? DDD - various graphical front-end of command-line debugger, GNU GPL3 or higher,
? Fab - let every time to build the optimal building systems, the GNU GPL3,
? GDB, The GNU Project debugger. A C debugger, GNU GPL3 or higher,
? Glade - a TK + GUIs development faster RAD tools, GNU GPL2.1,
? GMSL - the GNU Make Standard Library; A collection of GNU Make additional function, 3 - clause BSD,
? The GNU Global - a C source label tool, the GNU GPL3,
? Gprof - a performance analysis tool, part of the GNU binutils, GNU GPL3 or higher,
? Highlight - the source code into formatted text, Highlight the GNU GPL3,
? Include - what - you - use -- help programmers find unnecessary contains and offering solutions to their Suggestions, based on LLVM/Clang (can only work with it), NCSA,
? Indent - automatic formatting C code, makes it easier to read, also can get a style code into another, GNU GPL3 or higher,
? Make - a control program executable code and other files generated by the tool, the GNU GPL3 or higher (link to the realization of the GNU),
? Qo - without the construction of a separate configuration file system, the Expat,
? Rr - record non-deterministic execution to allow a debugger, can be set for the debug FreeBSD,
? Tup - a quick, based on documents, cross-platform, build the system, the GNU GPL2.1,
? Unifdef - remove # ifdef and # if directive contains text, will not change the other parts of the document, 3 - clause BSD and FreeBSD,
? Valgrind - all kinds of dynamic analysis tools, including a memory leak detection tool, the GNU GPL2.1,

Utility
Below is a comprehensive directory, mainly those who do not fit into the other directories,
? ApeTagLibs - APEv2 tags in the C library, the Expat,
? BFD - handling binary object file library, part of the GNU binutils, GNU GPL3 or higher,
? CCV - C - -based/Cached/Core Computer Vision library; The modern computer vision, 3 - clause BSD,
? Cf4ocl - The C Framework for OpenCL; A cross-platform object-oriented framework for development and test OpenCL project with benchmark problem, GNU LGPL3 (library), GNU GPL3 (other code),
? CommonMark - CommonMark C implementation specifications, Variety of licenses and all free,
? CException - abnormal C implementation, the Expat,
? Docopt. C - c implementation command line option parser, the Expat,
? Dyncall - another external function interface library, the Expat,
? FANN - Fast Artifical Neural Network library; A neural network implementation, GNU GPL2.1,
? Firm - a C library, provides intermediate representation based on images, optimization, and is suitable for the generated assembly code, the compiler is equipped with the front end of the C example, use the same license, the GNU LGPLv2.1,
? Gjrand - random Numbers generated Cheng Ku, GNU GPL2.1 or the GNU GPL (user choice),
? The GNU FreeIPMI - an in-band and out-of-band IPMI, GNU GPL3,
? The GNU gperf - a perfect hash function generator, provide a series of string, the output C code, the GNU GPL3 or higher,
? The GNU Libffcall - a collection of the building external interface function library, GNU GPL3 or higher,
? Gperftools - a series of measure and improve performance utility collection, 3 - clause BSD,
? Hammer - binary format parser combination, GNU GPL2.1.
? Huffandpuff - a tiny Huffman coder and decoder, the public domain,
? Iniparser - a. Ini file parser, the Expat,
? Jemalloc - a malloc implementation, focus on the segmentation fault avoiding and scalable concurrency support, FreeBSD,
? JwHash - a quick hash table implementation, Apache2.0,
? Simple library kdtree - KD - trees, 3 - clause BSD,
? Kitsune - efficient, general framework for dynamic upgrade software, GNU LGPL3 or higher,
? Libavl - a library including the balanced binary tree, the GNU GPL3 or higher,
? Libbson - BSON utility library, Apache2.0,
? LibCello - the introduction of advanced language to C library,
? Libcox - a cross-platform operation system calls and cross-system library of standard tools, FreeBSD,
? Libffi - lightweight external function interface library, the Expat,
? Libgit2 - pure C implementation of Git, GNU GPL2 only, with a linking exception,
? Libimobiledevice agreement - a cross-platform library, used to communicate with iThings, GNU LGPLv2.1 or higher (library), GNU GPL2.1 or higher (tools),
? Libmpv - music library, compile time to join. J/waf configure -- disable - cplayer - enable - libmpv - Shared to avoid generating music player, the GNU GPL2.1 or higher,
? Lzo library - a quick data compression, the GNU GPL2.1,
? The MPC - combinations of parser library, FreeBSD
? The ncurses terminal UI library - color, GNU GPL3 or higher,
? Nope. C - one based on c language, super lightweight software platform, used in extensible application server and network development (think c programmers nodejs),
? PBC - an agreement storage buffer, the Expat,
? The rabbitmq - c - the rabbitmq client library, the Expat,
? Ragel DSL for compiling C state machine, the GNU GPL2.1,
? Uthash - hash table implementation, allowing existing hash table data structure easily, 1 - clause BSD,
? Viola - libCello simplified version of the Expat,
? Zlib - but a pretty delicate and not make public the compression library, 3 - clause BSD,

XML
? The Expat - flow oriented XML parser, the Expat,
? Libxml2 - a fine, lightweight XML parser, the Expat,
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