int isfinite(fpval): Returns nonzero if fpval is finite. : isfinite « math.h « C Tutorial

1. C Tutorial
2. math.h
3. isfinite

#include <stdio.h>
#include <math.h>

int main(void)
{
  printf("isfinite(-1.0) %d\n", isfinite(-1.0));
  printf("isfinite(1.0) %d\n", isfinite(1.0));
  printf("isfinite(1.0/0.0) %d\n", isfinite(1.0/0.0));
  return 0;
}

isfinite(-1.0) 1
isfinite(1.0) 1
isfinite(1.0/0.0) 0