math_errhandling

/* math_errhandling example */
#include <stdio.h>      /* printf */
#include <math.h>       /* math_errhandling */
#include <errno.h>      /* errno, EDOM */
#include <fenv.h>       /* feclearexcept, fetestexcept, FE_ALL_EXCEPT, FE_INVALID */
#pragma STDC FENV_ACCESS on
int main () {
  errno = 0;
  if (math_errhandling & MATH_ERREXCEPT) feclearexcept(FE_ALL_EXCEPT);
  printf ("Error handling: %d",math_errhandling);
  sqrt (-1);
  if (math_errhandling & MATH_ERRNO) {
    if (errno==EDOM) printf("errno set to EDOM\n");
  }
  if (math_errhandling  &MATH_ERREXCEPT) {
    if (fetestexcept(FE_INVALID)) printf("FE_INVALID raised\n");
  }
  return 0;
}