Code:
SYNOPSIS
       #include <math.h>

       double fmod(double x, double y);

       float fmodf(float x, float y);

       long double fmodl(long double x, long double y);

DESCRIPTION
       The  fmod()  function  computes the remainder of dividing x by y.  The return value is x - n * y,
       where n is the quotient of x / y, rounded towards zero to an integer.