1*60b8f499Skettenis.\" $OpenBSD: ilogb.3,v 1.8 2020/10/31 15:14:39 kettenis Exp $ 2f66cd146Smartynas.\" Copyright (c) 1985, 1991 Regents of the University of California. 3f66cd146Smartynas.\" All rights reserved. 4f66cd146Smartynas.\" 5f66cd146Smartynas.\" Redistribution and use in source and binary forms, with or without 6f66cd146Smartynas.\" modification, are permitted provided that the following conditions 7f66cd146Smartynas.\" are met: 8f66cd146Smartynas.\" 1. Redistributions of source code must retain the above copyright 9f66cd146Smartynas.\" notice, this list of conditions and the following disclaimer. 10f66cd146Smartynas.\" 2. Redistributions in binary form must reproduce the above copyright 11f66cd146Smartynas.\" notice, this list of conditions and the following disclaimer in the 12f66cd146Smartynas.\" documentation and/or other materials provided with the distribution. 13f66cd146Smartynas.\" 3. Neither the name of the University nor the names of its contributors 14f66cd146Smartynas.\" may be used to endorse or promote products derived from this software 15f66cd146Smartynas.\" without specific prior written permission. 16f66cd146Smartynas.\" 17f66cd146Smartynas.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18f66cd146Smartynas.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19f66cd146Smartynas.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20f66cd146Smartynas.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21f66cd146Smartynas.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22f66cd146Smartynas.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23f66cd146Smartynas.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24f66cd146Smartynas.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25f66cd146Smartynas.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26f66cd146Smartynas.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27f66cd146Smartynas.\" SUCH DAMAGE. 28f66cd146Smartynas.\" 29f66cd146Smartynas.\" from: @(#)ieee.3 6.4 (Berkeley) 5/6/91 30f66cd146Smartynas.\" 31*60b8f499Skettenis.Dd $Mdocdate: October 31 2020 $ 32f66cd146Smartynas.Dt ILOGB 3 33f66cd146Smartynas.Os 34f66cd146Smartynas.Sh NAME 35f66cd146Smartynas.Nm ilogb , 36f66cd146Smartynas.Nm ilogbf , 37f66cd146Smartynas.Nm ilogbl 38f66cd146Smartynas.Nd extract exponent 39f66cd146Smartynas.Sh SYNOPSIS 4086f9d4cdStedu.In math.h 41f66cd146Smartynas.Ft int 42f66cd146Smartynas.Fn ilogb "double x" 43f66cd146Smartynas.Ft int 44f66cd146Smartynas.Fn ilogbf "float x" 45f66cd146Smartynas.Ft int 46f66cd146Smartynas.Fn ilogbl "long double x" 47f66cd146Smartynas.Sh DESCRIPTION 48f66cd146Smartynas.Fn ilogb 49f66cd146Smartynasreturns 50f66cd146Smartynas.Fa x Ns 's exponent 51f66cd146Smartynas.Fa n , 52f66cd146Smartynasin integer format. 539f1be2b6Stb.Fn ilogb \(+-infinity 54f66cd146Smartynasreturns 55*60b8f499Skettenis.Dv INT_MAX , 56*60b8f499Skettenis.Fn ilogb NaN 57*60b8f499Skettenisreturns 58*60b8f499Skettenis.Dv FP_ILOGBNAN 59f66cd146Smartynasand 60f66cd146Smartynas.Fn ilogb 0 61f66cd146Smartynasreturns 62*60b8f499Skettenis.Dv FP_ILOGB0 . 63f66cd146SmartynasThe 64f66cd146Smartynas.Fn ilogbf 65f66cd146Smartynasfunction is a single precision version of 66f66cd146Smartynas.Fn ilogb . 67f66cd146SmartynasThe 68f66cd146Smartynas.Fn ilogbl 69f66cd146Smartynasfunction is an extended precision version of 70f66cd146Smartynas.Fn ilogb . 71f66cd146Smartynas.Sh SEE ALSO 72b1845aa3Sespie.Xr ffs 3 , 730714f1f8Smartynas.Xr frexp 3 74f66cd146Smartynas.Sh STANDARDS 75f66cd146Smartynas.St -ieee754 76f66cd146Smartynas.Sh HISTORY 77f66cd146SmartynasThe 78f66cd146Smartynas.Nm ilogb , 798f740a56Smartynas.Nm ilogbf 80f66cd146Smartynasand 81f66cd146Smartynas.Nm ilogbl 82f66cd146Smartynasfunctions appeared in 838f740a56Smartynas.Bx 4.3 , 848f740a56Smartynas.Nx 1.1 858f740a56Smartynasand 868f740a56Smartynas.Ox 4.5 , 878f740a56Smartynasrespectively. 88