1.\" $NetBSD: stdbool.3,v 1.2 2010/05/14 02:45:39 joerg Exp $ 2.\" 3.\" Copyright (c) 2010 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Jukka Ruohonen. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 19.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 20.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 21.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 22.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28.\" POSSIBILITY OF SUCH DAMAGE. 29.\" 30.Dd March 21, 2010 31.Dt STDBOOL 3 32.Os 33.Sh NAME 34.Nm stdbool 35.Nd standard boolean types 36.Sh SYNOPSIS 37.In stdbool.h 38.Sh DESCRIPTION 39The 40.In stdbool.h 41header defines four macros: 42.Bl -enum -offset 4n 43.It 44.Vt bool , 45which expands to 46.Vt _Bool ; 47.It 48.Vt true , 49which expands to the integer constant 1; 50.It 51.Vt false , 52which expands to the integer constant 0; and 53.It 54.Vt __bool_true_false_are_defined , 55which expands to the constant 1. 56.El 57.Pp 58The ability to undefine and redefine the macros 59.Vt bool , 60.Vt true , 61and 62.Vt false 63is an obsolescent feature that may 64be withdrawn in a future version of a standard. 65.Sh SEE ALSO 66.Xr stdint 3 67.Sh STANDARDS 68The 69.In stdbool.h 70header conforms to 71.St -isoC-99 72and 73.St -p1003.1-2001 . 74.Sh HISTORY 75The 76.In stdbool.h 77header was first introduced in 78.Nx 1.6 . 79