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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():
       _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L

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.

ATTRIBUTES

   For   an   explanation   of   the  terms  used  in  this  section,  see
   attributes(7).

   
   Interface           Attribute      Value   
   
   abs(), labs(),      Thread safety  MT-Safe 
   llabs(), imaxabs()

CONFORMING TO

   POSIX.1-2001,  POSIX.1-2008,  C99, SVr4, 4.3BSD.  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.   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.

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

SEE ALSO

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

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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