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	1	.\" Copyright (c) 1990, 1991, 1993, 1994
	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. All advertising materials mentioning features or use of this software
	17	.\" must display the following acknowledgement:
	18	.\" This product includes software developed by the University of
	19	.\" California, Berkeley and its contributors.
	20	.\" 4. Neither the name of the University nor the names of its contributors
	21	.\" may be used to endorse or promote products derived from this software
	22	.\" without specific prior written permission.
	23	.\"
	24	.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	25	.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	26	.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	27	.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	28	.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	29	.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	30	.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	31	.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	32	.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	33	.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	34	.\" SUCH DAMAGE.
	35	.\"
	36	.\" @(#)bsearch.3 8.3 (Berkeley) 4/19/94
	37	.\" $FreeBSD: src/lib/libc/stdlib/bsearch.3,v 1.4.2.4 2001/12/14 18:33:58 ru Exp $
	38	.\"
	39	.Dd April 19, 1994
	40	.Dt BSEARCH 3
	41	.Os
	42	.Sh NAME
	43	.Nm bsearch
	44	.Nd binary search of a sorted table
	45	.Sh LIBRARY
	46	.Lb libc
	47	.Sh SYNOPSIS
	48	.In stdlib.h
	49	.Ft void *
	50	.Fn bsearch "const void key" "const void base" "size_t nmemb" "size_t size" "int (compar) (const void , const void *)"
	51	.Sh DESCRIPTION
	52	The
	53	.Fn bsearch
	54	function searches an array of
	55	.Fa nmemb
	56	objects, the initial member of which is
	57	pointed to by
	58	.Fa base ,
	59	for a member that matches the object pointed to by
	60	.Fa key .
	61	The size of each member of the array is specified by
	62	.Fa size .
	63	.Pp
	64	The contents of the array should be in ascending sorted order according
	65	to the comparison function referenced by
	66	.Fa compar .
	67	The
	68	.Fa compar
	69	routine
	70	is expected to have
	71	two arguments which point to the
	72	.Fa key
	73	object and to an array member, in that order, and should return an integer
	74	less than, equal to, or greater than zero if the
	75	.Fa key
	76	object is found, respectively, to be less than, to match, or be
	77	greater than the array member.
	78	.Sh RETURN VALUES
	79	The
	80	.Fn bsearch
	81	function returns a pointer to a matching member of the array, or a null
	82	pointer if no match is found.
	83	If two members compare as equal, which member is matched is unspecified.
	84	.Sh SEE ALSO
	85	.Xr db 3 ,
	86	.Xr lsearch 3 ,
	87	.Xr qsort 3
	88	.\" .Xr tsearch 3
	89	.Sh STANDARDS
	90	The
	91	.Fn bsearch
	92	function conforms to
	93	.St -isoC .