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 4.15 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/.