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INFNAN

Section: Linux Programmer's Manual (3)
Updated: 1993-06-02
Index Return to Main Contents

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.

COLOPHON

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