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This section describes functions for performing integer division. These
functions are redundant when GNU CC is used, because 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.
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.
Preliminary: | MT-Safe | AS-Safe | AC-Safe | See POSIX Safety Concepts.
The 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
.
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
.)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | See POSIX Safety Concepts.
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_t
.
This is a structure type used to hold the result returned by the lldiv
function. It has the following members:
long long int quot
The quotient from the division.
long long int rem
The remainder from the division.
(This is identical to div_t
except that the components are of
type long long int
rather than int
.)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | See POSIX Safety Concepts.
The lldiv
function is like the div
function, but the
arguments are of type long long int
and the result is returned as
a structure of type lldiv_t
.
The lldiv
function was added in ISO C99.
This is a structure type used to hold the result returned by the imaxdiv
function. It has the following members:
intmax_t quot
The quotient from the division.
intmax_t rem
The remainder from the division.
(This is identical to div_t
except that the components are of
type intmax_t
rather than int
.)
See Integers for a description of the intmax_t
type.
Preliminary: | MT-Safe | AS-Safe | AC-Safe | See POSIX Safety Concepts.
The imaxdiv
function is like the div
function, but the
arguments are of type intmax_t
and the result is returned as
a structure of type imaxdiv_t
.
See Integers for a description of the intmax_t
type.
The imaxdiv
function was added in ISO C99.
Next: Floating Point Numbers, Previous: Integers, Up: Arithmetic Functions [Contents][Index]