The GNU C Library - Integer Division

Integer Division

This section describes functions for performing integer division. These functions are redundant in the GNU C library, since in GNU C the `/' operator always rounds towards zero. But in other C implementations, `/' may round differently with negative arguments. div and ldiv are useful because they specify how to round the quotient: towards zero. The remainder has the same sign as the numerator.

These functions are specified to return a result r such that the value r.quot*denominator + r.rem equals numerator.

To use these facilities, you should include the header file `stdlib.h' in your program.

Data Type div_t

This is a structure type used to hold the result returned by the div function. It has the following members:

int quot

The quotient from the division.

int rem

The remainder from the division.

Function div_t div (int numerator, int denominator)

This function div computes the quotient and remainder from the division of numerator by denominator, returning the result in a structure of type div_t .

If the result cannot be represented (as in a division by zero), the behavior is undefined.

Here is an example, albeit not a very useful one.

	div_t result;
	result = div (20, -6);

Now result.quot is -3 and result.rem is 2 .

Data Type ldiv_t

This is a structure type used to hold the result returned by the ldiv function. It has the following members:

long int quot

The quotient from the division.

long int rem

The remainder from the division.

(This is identical to div_t except that the components are of type long int rather than int .)

Function ldiv_t ldiv (long int numerator, long int denominator)

The ldiv function is similar to div , except that the arguments are of type long int and the result is returned as a structure of type ldiv .