1.\" Copyright (c) 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" the American National Standards Committee X3, on Information 6.\" Processing Systems. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)frexp.3 8.1 (Berkeley) 6/4/93 33.\" $FreeBSD: head/lib/libc/gen/frexp.3 206616 2010-04-14 18:29:34Z uqs $ 34.\" 35.Dd March 4, 2005 36.Dt FREXP 3 37.Os 38.Sh NAME 39.Nm frexp , 40.Nm frexpf , 41.Nm frexpl 42.Nd convert floating-point number to fractional and integral components 43.Sh LIBRARY 44.Lb libm 45.Sh SYNOPSIS 46.In math.h 47.Ft double 48.Fn frexp "double value" "int *exp" 49.Ft float 50.Fn frexpf "float value" "int *exp" 51.Ft long double 52.Fn frexpl "long double value" "int *exp" 53.Sh DESCRIPTION 54The 55.Fn frexp , 56.Fn frexpf 57and 58.Fn frexpl 59functions break a floating-point number into a normalized 60fraction and an integral power of 2. 61They store the integer in the 62.Vt int 63object pointed to by 64.Fa exp . 65.Sh RETURN VALUES 66These functions return the value 67.Va x , 68such that 69.Va x 70is a 71.Vt double 72with magnitude in the interval 73.Eo [ 1/2 , 1 Ec ) 74or zero, and 75.Fa value 76equals 77.Va x 78times 2 raised to the power 79.Fa *exp . 80If 81.Fa value 82is zero, both parts of the result are zero. 83.Sh SEE ALSO 84.Xr ldexp 3 , 85.Xr math 3 , 86.Xr modf 3 87.Sh STANDARDS 88The 89.Fn frexp , 90.Fn frexpf , 91and 92.Fn frexpl 93functions conform to 94.St -isoC-99 . 95