FABS(3) Library Functions Manual FABS(3)
NAME
fabs — absolute
value function
SYNOPSIS
#include <math.h> double fabs(double x);
DESCRIPTION
The fabs() function computes the absolute value of x , | x |.
An application wishing to check for error situations should set errno to 0 before calling fabs(). If errno is non-zero on return, or the return value is NaN, an error has occurred.
RETURN VALUE
Upon successful completion, fabs() returns the absolute value of x .
If x is NaN, NaN is returned and errno may be set to [EDOM].
If the result underflows, 0 is returned and errno may be set to [ERANGE].
ERRORS
The fabs() function may fail if:
No other errors will occur.
EXAMPLES
None.
APPLICATION USAGE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
DERIVATION
Derived from Issue 1 of the SVID.
February 1997 posix.fail