Glib, libc, other C library

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LIBC(7)                    Linux Programmer's Manual                   LIBC(7)NAME       libc - Overview of standard C libraries on LinuxDESCRIPTION       The  term  "libc"  is  commonly used as a shorthand for the "standard C       library", a library of standard functions that can be  used  by  all  C       programs  (and  sometimes  by programs in other languages).  Because of       some history (see below), use of the term "libc" to refer to the  stan-       dard C library is somewhat ambiguous on Linux.   glibc       By  far  the  most  widely used C library on Linux is the GNU C Library       (http://www.gnu.org/software/libc/), often referred to as glibc.   This       is  the  C  library  that is nowadays used in all major Linux distribu-       tions.  It is also the C library whose details are  documented  in  the       relevant  pages of the man-pages project (primarily in Section 3 of the       manual).  Documentation of glibc is also available in the glibc manual,       available  via the command info libc.  Release 1.0 of glibc was made in       September 1992.  (There were earlier 0.x  releases.)   The  next  major       release of glibc was 2.0, at the beginning of 1997.       The  pathname  /lib/libc.so.6 (or something similar) is normally a sym-       bolic link that points to the location of the glibc library,  and  exe-       cuting  this  pathname  will cause glibc to display various information       about the version installed on your system.   Linux libc       In the early to mid 1990s, there was for a while Linux libc, a fork  of       glibc  1.x  created by Linux developers who felt that glibc development       at the time was not sufficing for the  needs  of  Linux.   Often,  this       library  was  referred  to  (ambiguously)  as  just "libc".  Linux libc       released major versions 2, 3, 4, and 5 (as well as many minor  versions       of those releases).  For a while, Linux libc was the standard C library       in many Linux distributions.   However,  notwithstanding  the  original       motivations  of  the  Linux  libc  effort,  by  the  time glibc 2.0 was       released, it was clearly superior to Linux libc, and  all  major  Linux       distributions  that  had  been  using  Linux libc soon switched back to       glibc.  (Since this switch occurred over a  decade  ago,  man-pages  no       longer  takes  care  to document Linux libc details.  Nevertheless, the       history is visible in vestiges of information  about  Linux  libc  that       remain  in  some  manual  pages, in particular, references to libc4 and       libc5.)   Other C libraries       There are various other less widely used C libraries for Linux.   These       libraries  are  generally smaller than glibc, both in terms of features       and memory footprint, and often intended for building  small  binaries,       perhaps targeted at development for embedded Linux systems.  Among such       libraries   are   uClibc    (http://www.uclibc.org/)    and    dietlibc       (http://www.fefe.de/dietlibc/).   Details of these libraries are gener-       ally not covered by the man-pages project.SEE ALSO       syscalls(2), feature_test_macros(7), man-pages(7), standards(7)COLOPHON       This page is part of release 3.27 of the Linux  man-pages  project.   A       description  of  the project, and information about reporting bugs, can       be found at http://www.kernel.org/doc/man-pages/.Linux                             2009-01-13                           LIBC(7)