abs(3) — Linux manual page


abs(3)                  Library Functions Manual                  abs(3)

NAME         top

       abs, labs, llabs, imaxabs - compute the absolute value of an

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <stdlib.h>

       int abs(int j);
       long labs(long j);
       long long llabs(long long j);

       #include <inttypes.h>

       intmax_t imaxabs(intmax_t j);

   Feature Test Macro Requirements for glibc (see

           _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L

DESCRIPTION         top

       The abs() function computes the absolute value of the integer
       argument j.  The labs(), llabs(), and imaxabs() functions compute
       the absolute value of the argument j of the appropriate integer
       type for the function.

RETURN VALUE         top

       Returns the absolute value of the integer argument, of the
       appropriate integer type for the function.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       │ Interface                           Attribute     Value   │
       │ abs(), labs(), llabs(), imaxabs()   │ Thread safety │ MT-Safe │

STANDARDS         top

       C11, POSIX.1-2008.

HISTORY         top

       POSIX.1-2001, C99, SVr4, 4.3BSD.

       C89 only includes the abs() and labs() functions; the functions
       llabs() and imaxabs() were added in C99.

NOTES         top

       Trying to take the absolute value of the most negative integer is
       not defined.

       The llabs() function is included since glibc 2.0.  The imaxabs()
       function is included since glibc 2.1.1.

       For llabs() to be declared, it may be necessary to define
       _ISOC99_SOURCE or _ISOC9X_SOURCE (depending on the version of
       glibc) before including any standard headers.

       By default, GCC handles abs(), labs(), and (since GCC 3.0)
       llabs() and imaxabs() as built-in functions.

SEE ALSO         top

       cabs(3), ceil(3), fabs(3), floor(3), rint(3)

COLOPHON         top

       This page is part of the man-pages (Linux kernel and C library
       user-space interface documentation) project.  Information about
       the project can be found at 
       ⟨https://www.kernel.org/doc/man-pages/⟩.  If you have a bug report
       for this manual page, see
       This page was obtained from the tarball man-pages-6.9.1.tar.gz
       fetched from
       ⟨https://mirrors.edge.kernel.org/pub/linux/docs/man-pages/⟩ on
       2024-06-26.  If you discover any rendering problems in this HTML
       version of the page, or you believe there is a better or more up-
       to-date source for the page, or you have corrections or
       improvements to the information in this COLOPHON (which is not
       part of the original manual page), send a mail to

Linux man-pages 6.9.1          2024-05-02                         abs(3)

Pages that refer to this page: cabs(3)div(3)fabs(3)_Generic(3)strtoimax(3)wcstoimax(3)