FMOD
Section: Linux Programmer's Manual (3)
Updated: 20120315
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NAME
fmod, fmodf, fmodl  floatingpoint remainder function
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);
Link with lm.
Feature Test Macro Requirements for glibc (see
feature_test_macros(7)):
fmodf(),
fmodl():

_BSD_SOURCE  _SVID_SOURCE  _XOPEN_SOURCE >= 600  _ISOC99_SOURCE 
_POSIX_C_SOURCE >= 200112L;
or
cc std=c99
DESCRIPTION
The
fmod()
function computes the floatingpoint remainder of dividing
x
by
y.
The return value is
x

n
*
y,
where
n
is the quotient of
x
/
y,
rounded toward zero to an integer.
RETURN VALUE
On success, these
functions return the value
x 
n*
y,
for some integer
n,
such that the returned value has the same sign as
x
and a magnitude less than the magnitude of
y.
If
x
or
y
is a NaN, a NaN is returned.
If
x
is an infinity,
a domain error occurs, and
a NaN is returned.
If
y
is zero,
a domain error occurs, and
a NaN is returned.
If
x
is +0 (0), and
y
is not zero, +0 (0) is returned.
ERRORS
See
math_error(7)
for information on how to determine whether an error has occurred
when calling these functions.
The following errors can occur:
 Domain error: x is an infinity

errno
is set to
EDOM
(but see BUGS).
An invalid floatingpoint exception
(FE_INVALID)
is raised.
 Domain error: y is zero

errno
is set to
EDOM.
An invalid floatingpoint exception
(FE_INVALID)
is raised.
CONFORMING TO
C99, POSIX.12001.
The variant returning
double
also conforms to
SVr4, 4.3BSD, C89.
BUGS
Before version 2.10, the glibc implementation did not set
errno
to
EDOM
when a domain error occurred for an infinite
x.
SEE ALSO
remainder(3)
COLOPHON
This page is part of release 3.74 of the Linux
manpages
project.
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
http://www.kernel.org/doc/manpages/.
Index
 NAME

 SYNOPSIS

 DESCRIPTION

 RETURN VALUE

 ERRORS

 CONFORMING TO

 BUGS

 SEE ALSO

 COLOPHON
