1 .\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
2 .\" and Copyright 2008, Linux Foundation, written by Michael Kerrisk
3 .\" <mtk.manpages@gmail.com>
5 .\" %%%LICENSE_START(VERBATIM)
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13 .\" permission notice identical to this one.
15 .\" Since the Linux kernel and libraries are constantly changing, this
16 .\" manual page may be incorrect or out-of-date. The author(s) assume no
17 .\" responsibility for errors or omissions, or for damages resulting from
18 .\" the use of the information contained herein. The author(s) may not
19 .\" have taken the same level of care in the production of this manual,
20 .\" which is licensed free of charge, as they might when working
23 .\" Formatted or processed versions of this manual, if unaccompanied by
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27 .\" References consulted:
28 .\" Linux libc source code
29 .\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
31 .\" Modified 1993-07-24 by Rik Faith (faith@cs.unc.edu)
32 .\" Modified 2002-07-27 by Walter Harms
33 .\" (walter.harms@informatik.uni-oldenburg.de)
35 .TH FMOD 3 2012-03-15 "" "Linux Programmer's Manual"
37 fmod, fmodf, fmodl \- floating-point remainder function
42 .BI "double fmod(double " x ", double " y );
44 .BI "float fmodf(float " x ", float " y );
46 .BI "long double fmodl(long double " x ", long double " y );
52 Feature Test Macro Requirements for glibc (see
53 .BR feature_test_macros (7)):
60 _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE\ >=\ 600 || _ISOC99_SOURCE ||
61 _POSIX_C_SOURCE\ >=\ 200112L;
70 function computes the floating-point remainder of dividing
86 rounded toward zero to an integer.
89 functions return the value \fIx\fP\ \-\ \fIn\fP*\fIy\fP,
92 such that the returned value has the same sign as
94 and a magnitude less than the magnitude of
101 is a NaN, a NaN is returned.
106 a domain error occurs, and
112 a domain error occurs, and
119 is not zero, +0 (\-0) is returned.
123 for information on how to determine whether an error has occurred
124 when calling these functions.
126 The following errors can occur:
128 Domain error: \fIx\fP is an infinity
133 An invalid floating-point exception
137 Domain error: \fIy\fP is zero
141 An invalid floating-point exception
144 .\" POSIX.1 documents an optional underflow error, but AFAICT it doesn't
145 .\" (can't?) occur -- mtk, Jul 2008
148 The variant returning
153 Before version 2.10, the glibc implementation did not set
154 .\" http://sources.redhat.com/bugzilla/show_bug.cgi?id=6784
158 when a domain error occurred for an infinite