ISINF(3)                  OpenBSD Programmer's Manual                 ISINF(3)

NAME
     isinf, isinff, isnan, isnanf - test for infinity or not-a-number

SYNOPSIS
     #include <math.h>

     int
     isinf(double n);

     int
     isinff(float n);

     int
     isnan(double n);

     int
     isnanf(float n);

DESCRIPTION
     The isinf() and isinff() functions returns 1 if the number n is infinity,
     otherwise 0.

     The isnan() and isnanf() functions returns 1 if the number n is ``not-a-
     number'', otherwise 0.

SEE ALSO
     math(3)

     IEEE Standard for Binary Floating-Point Arithmetic, Std 754-1985, ANSI.

BUGS
     Neither the VAX nor the Tahoe floating point have distinguished values
     for either infinity or not-a-number.  These routines always return 0 on
     those architectures.

OpenBSD 2.6                    January 29, 1994                              1
