DREM(3) Linux Programmer's Manual DREM(3)
NAME
drem - floating-point remainder function
SYNOPSIS
#include<math.h>
doubledrem(double x,double y);
DESCRIPTION
The drem() 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 to
the nearest integer. If the quotient is 1/2, it is rounded to the even
number.
RETURNVALUE
The drem() function returns the remainder, unless y is zero, when the
function fails and errno is set.
ERRORS
EDOM The denominator y is zero.
CONFORMINGTO
BSD 4.3
SEEALSO
fmod(3)
1993-06-06 DREM(3)
Take our 
