1.\" $OpenBSD: fmod.3,v 1.10 2011/07/07 01:34:52 martynas Exp $ 2.\" Copyright (c) 1991 The Regents of the University of California. 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 3. Neither the name of the University nor the names of its contributors 14.\" may be used to endorse or promote products derived from this software 15.\" without specific prior written permission. 16.\" 17.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27.\" SUCH DAMAGE. 28.\" 29.\" from: @(#)fmod.3 5.1 (Berkeley) 5/2/91 30.\" 31.Dd $Mdocdate: July 7 2011 $ 32.Dt FMOD 3 33.Os 34.Sh NAME 35.Nm fmod , 36.Nm fmodf , 37.Nm fmodl 38.Nd floating-point remainder functions 39.Sh SYNOPSIS 40.Fd #include <math.h> 41.Ft double 42.Fn fmod "double x" "double y" 43.Ft float 44.Fn fmodf "float x" "float y" 45.Ft long double 46.Fn fmodl "long double x" "long double y" 47.Sh DESCRIPTION 48The 49.Fn fmod 50function computes the floating-point remainder of 51.Fa x Ns / Fa y . 52The 53.Fn fmodf 54function is a single precision version of 55.Fn fmod . 56The 57.Fn fmodl 58function is an extended precision version of 59.Fn fmod . 60.Sh RETURN VALUES 61The 62.Fn fmod , 63.Fn fmodf 64and 65.Fn fmodl 66functions return the value 67.Sm off 68.Fa x - Em i * Fa y , 69.Sm on 70for some integer 71.Em i 72such that, if 73.Fa y 74is non-zero, the result has the same sign as 75.Fa x 76and magnitude less than the magnitude of 77.Fa y . 78If 79.Fa y 80is zero, whether a domain error occurs or the 81.Fn fmod 82function returns zero is implementation-defined. 83.Sh SEE ALSO 84.Xr remainder 3 85.Sh STANDARDS 86The 87.Fn fmod 88function conforms to 89.St -ansiC . 90