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            "text": "# glibc (info)\n\n## NAME\n\nlibc - overview of standard C libraries on Linux\n\n## DESCRIPTION\n\nThe term \"libc\" is commonly used as a shorthand for the \"standard C li-\nbrary\", a library of standard functions that can be used by all C  pro-\ngrams  (and sometimes by programs in other languages).  Because of some\nhistory (see below), use of the term \"libc\" to refer to the standard  C\nlibrary is somewhat ambiguous on Linux.\n\n## Sections\n\n- **NAME**\n- **DESCRIPTION**\n- **SEE ALSO**\n- **COLOPHON**\n\nUse structuredContent.sections for detailed options, examples, and full documentation.\n"
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            "NAME": {
                "content": "libc - overview of standard C libraries on Linux\n",
                "subsections": []
            },
            "DESCRIPTION": {
                "content": "The term \"libc\" is commonly used as a shorthand for the \"standard C li-\nbrary\", a library of standard functions that can be used by all C  pro-\ngrams  (and sometimes by programs in other languages).  Because of some\nhistory (see below), use of the term \"libc\" to refer to the standard  C\nlibrary is somewhat ambiguous on Linux.\n\nglibc\nBy  far  the  most  widely used C library on Linux is the GNU C Library\n<http://www.gnu.org/software/libc/>, often referred to as glibc.   This\nis  the  C  library  that is nowadays used in all major Linux distribu-\ntions.  It is also the C library whose details are  documented  in  the\nrelevant  pages of the man-pages project (primarily in Section 3 of the\nmanual).  Documentation of glibc is also available in the glibc manual,\navailable  via the command info libc.  Release 1.0 of glibc was made in\nSeptember 1992.  (There were earlier 0.x releases.)  The next major re-\nlease of glibc was 2.0, at the beginning of 1997.\n\nThe  pathname  /lib/libc.so.6 (or something similar) is normally a sym-\nbolic link that points to the location of the glibc library,  and  exe-\ncuting  this  pathname  will cause glibc to display various information\nabout the version installed on your system.\n\nLinux libc\nIn the early to mid 1990s, there was for a while Linux libc, a fork  of\nglibc  1.x  created by Linux developers who felt that glibc development\nat the time was not sufficing for the needs of Linux.  Often, this  li-\nbrary  was  referred  to  (ambiguously) as just \"libc\".  Linux libc re-\nleased major versions 2, 3, 4, and 5, as well as many minor versions of\nthose  releases.  Linux libc4 was the last version to use the a.out bi-\nnary format, and the first version to provide  (primitive)  shared  li-\nbrary  support.   Linux libc 5 was the first version to support the ELF\nbinary format; this version used the shared library  soname  libc.so.5.\nFor  a  while, Linux libc was the standard C library in many Linux dis-\ntributions.\n\nHowever, notwithstanding the original motivations of the Linux libc ef-\nfort,  by the time glibc 2.0 was released (in 1997), it was clearly su-\nperior to Linux libc, and all major Linux distributions that  had  been\nusing  Linux  libc soon switched back to glibc.  To avoid any confusion\nwith Linux libc versions, glibc 2.0 and later used the  shared  library\nsoname libc.so.6.\n\nSince  the  switch from Linux libc to glibc 2.0 occurred long ago, man-\npages no longer takes care to document Linux libc  details.   Neverthe-\nless,  the  history  is  visible in vestiges of information about Linux\nlibc that remain in a few manual pages, in  particular,  references  to\nlibc4 and libc5.\n\nOther C libraries\nThere  are various other less widely used C libraries for Linux.  These\nlibraries are generally smaller than glibc, both in terms  of  features\nand  memory  footprint, and often intended for building small binaries,\nperhaps targeted at development for embedded Linux systems.  Among such\nlibraries     are     uClibc     <http://www.uclibc.org/>,     dietlibc\n<http://www.fefe.de/dietlibc/>,         and          musl          libc\n<http://www.musl-libc.org/>.  Details of these libraries are covered by\nthe man-pages project, where they are known.\n",
                "subsections": []
            },
            "SEE ALSO": {
                "content": "syscalls(2),     getauxval(3),     proc(5),     featuretestmacros(7),\nman-pages(7), standards(7), vdso(7)\n",
                "subsections": []
            },
            "COLOPHON": {
                "content": "This  page  is  part of release 5.10 of the Linux man-pages project.  A\ndescription of the project, information about reporting bugs,  and  the\nlatest     version     of     this    page,    can    be    found    at\nhttps://www.kernel.org/doc/man-pages/.\n\nLinux                             2016-12-12                           LIBC(7)",
                "subsections": []
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