| ISINFF(3) | Library Functions Manual | ISINFF(3) | 
NAME
 isinff, isnanf — test for infinity or not-a-number
LIBRARY
 Math Library (libm, -lm)
SYNOPSIS
 #include <math.h>
int
isinff(float);
int
isnanf(float);
 
DESCRIPTION
 The 
isinff() function returns 1 if the number is “infinity”, otherwise 0.
The isnanf() function returns 1 if the number is “not-a-number”, otherwise 0.
 
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.