abs(3) — Linux manual page

abs(3)                   Library Functions Manual                  abs(3)

NAME         top

       abs, labs, llabs, imaxabs, uabs, ulabs, ullabs, uimaxabs - compute
       the absolute value of an integer

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);

       unsigned int uabs(int j);
       unsigned long ulabs(long j);
       unsigned long long ullabs(long long j);

       #include <inttypes.h>

       intmax_t imaxabs(intmax_t j);
       uintmax_t uimaxabs(intmax_t j);

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

       llabs():
           _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L

       uabs(), ulabs(), ullabs(), uimaxabs():
           _ISOC2Y_SOURCE

DESCRIPTION         top

       These 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
       attributes(7).
       ┌──────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                            │ Attribute     │ Value   │
       ├──────────────────────────────────────┼───────────────┼─────────┤
       │ abs(), labs(), llabs(), imaxabs(),   │ Thread safety │ MT-Safe │
       │ uabs(), ulabs(), ullabs(),           │               │         │
       │ uimaxabs()                           │               │         │
       └──────────────────────────────────────┴───────────────┴─────────┘

STANDARDS         top

       abs()
       labs()
       llabs()
       imaxabs()
              C23, POSIX.1-2024

HISTORY         top

       abs()  C89, POSIX.1-1996, SVr4, 4.3BSD.

       labs() C89, POSIX.1-2001.

       llabs()
              C99, POSIX.1-2001; glibc 2.0.

       imaxabs()
              C99, POSIX.1-2001; glibc 2.1.1.

       uabs()
       ulabs()
       ullabs()
       uimaxabs()
              C2y; glibc 2.42.

BUGS         top

       For abs(), labs(), llabs(), and imaxabs(), trying to take the
       absolute value of the most negative integer is not defined.

SEE ALSO         top

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

COLOPHON         top

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Linux man-pages 6.15            2025-05-17                         abs(3)

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

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