infnan(3) - Linux man page

Name

infnan - deal with infinite or not-a-number (NaN) result

Synopsis

#include <math.h>
double infnan(int error);

Link with -lm.

Description

The infnan() function returns a suitable value for infinity and "not-a-number" (NaN) results. The value of error can be ERANGE to represent infinity or anything else to represent NaN. errno is also set.

Return Value

If error is ERANGE (Infinity), HUGE_VAL is returned.

If error is -ERANGE (-Infinity), -HUGE_VAL is returned.

If error is anything else, NAN is returned.

Errors

EDOM: The value of error is "not-a-number" (NaN).
ERANGE: The value of error is positive infinity or negative infinity.

Conforming to

4.3BSD.

Notes

This obsolete function was provided in libc4 and libc5, but is not available in glibc2.