intro(3)


NAME

   intro - introduction to library functions

DESCRIPTION

   Section  3  of the manual describes all library functions excluding the
   library functions (system call wrappers) described in Section 2,  which
   implement system calls.

   Many of the functions described in the section are part of the Standard
   C Library (libc).  Some functions are part of  other  libraries  (e.g.,
   the  math library, libm, or the real-time library, librt) in which case
   the manual page will indicate the linker option needed to link  against
   the  required  library  (e.g.,  -lm  and  -lrt,  respectively,  for the
   aforementioned libraries).

   In some cases, the programmer must define a feature test macro in order
   to  obtain the declaration of a function from the header file specified
   in the man page SYNOPSIS section.  (Where required, these feature  test
   macros  must  be  defined  before including any header files.)  In such
   cases, the required macro is described in the man  page.   For  further
   information on feature test macros, see feature_test_macros(7).

CONFORMING TO

   Certain  terms and abbreviations are used to indicate UNIX variants and
   standards to which calls in this section conform.  See standards(7).

NOTES

   Authors and copyright conditions
   Look at the header of the manual page  source  for  the  author(s)  and
   copyright  conditions.   Note  that these can be different from page to
   page!

SEE ALSO

   intro(2),  errno(3),   capabilities(7),   credentials(7),   environ(7),
   feature_test_macros(7),   libc(7),  math_error(7),  path_resolution(7),
   pthreads(7), signal(7), standards(7)

COLOPHON

   This page is part of release 4.09 of the Linux  man-pages  project.   A
   description  of  the project, information about reporting bugs, and the
   latest    version    of    this    page,    can     be     found     at
   https://www.kernel.org/doc/man-pages/.





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