ABS(3)                                              Linux Programmer's Manual                                             ABS(3)



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

SYNOPSIS
       #include <stdlib.h>

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

       #include <inttypes.h>

       intmax_t imaxabs(intmax_t j);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       llabs(): _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE; or cc -std=c99

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

CONFORMING TO
       SVr4, POSIX.1-2001, 4.3BSD, C99.  C89 only includes the abs() and labs() functions; the functions llabs()  and  imaxabs()
       were added in C99.

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

       The  llabs()  function  is  included in glibc since version 2.0, but is not in libc5 or libc4.  The imaxabs() function is
       included in glibc since version 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.

       GCC handles abs() and labs() as built-in functions.  GCC 3.0 also handles llabs() and imaxabs() as built-ins.

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

COLOPHON
       This  page  is  part of release 3.25 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/.



GNU                                                        2007-07-26                                                     ABS(3)