F.9.7.1 The fmod functions

1

• fmod((+-)0, y) returns (+-)0 for y not zero.

• fmod(x, y) returns a NaN and raises the “invalid” floating-point exception for x infinite or y zero.

• fmod(x, (+-)(inf)) returns x for x not infinite.

2

The double version of fmod behaves as though implemented by

#include <math.h>
#include <fenv.h>
#pragma STDC FENV_ACCESS ON
double fmod(double x, double y)
{
     double result;
     result = remainder(fabs(x), (y = fabs(y)));
     if (signbit(result)) result += y;
     return copysign(result, x);
}