abs man page


This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

abs — return an integer absolute value


#include <stdlib.h>

int abs(int i);


The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of POSIX.1‐2008 defers to the ISO C standard.

The abs() function shall compute the absolute value of its integer operand, i. If the result cannot be represented, the behavior is undefined.

Return Value

The abs() function shall return the absolute value of its integer operand.


No errors are defined.

The following sections are informative.

Application Usage

In two's-complement representation, the absolute value of the negative integer with largest magnitude {INT_MIN} might not be representable.

See Also

fabs(), labs()

The Base Definitions volume of POSIX.1‐2008, <stdlib.h>