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	1	.\"
	2	.\" Initial implementation:
	3	.\" Copyright (c) 2002 Robert Drehmel
	4	.\" All rights reserved.
	5	.\"
	6	.\" As long as the above copyright statement and this notice remain
	7	.\" unchanged, you can do what ever you want with this file.
	8	.\"
	9	.\" $FreeBSD: src/lib/libc/stdlib/lsearch.3,v 1.4 2002/12/19 09:40:24 ru Exp $
	10	.\"
	11	.Dd October 11, 2002
	12	.Dt LSEARCH 3
	13	.Os
	14	.Sh NAME
	15	.Nm lfind ,
	16	.Nm lsearch
	17	.Nd linear search and append
	18	.Sh LIBRARY
	19	.Lb libc
	20	.Sh SYNOPSIS
	21	.In search.h
	22	.Ft "void *"
	23	.Fo lfind
	24	.Fa "const void key" "const void base" "size_t *nelp" "size_t width"
	25	.Fa "int \[lp]compar\[rp]\[lp]const void , const void \*[rp]"
	26	.Fc
	27	.Ft "void *"
	28	.Fo lsearch
	29	.Fa "const void key" "void base" "size_t *nelp" "size_t width"
	30	.Fa "int \[lp]compar\[rp]\[lp]const void , const void \*[rp]"
	31	.Fc
	32	.Sh DESCRIPTION
	33	The
	34	.Fn lsearch
	35	and
	36	.Fn lfind
	37	functions walk linearly through an array, comparing each element with
	38	the one to be sought, by means of a supplied comparison function.
	39	.Pp
	40	The
	41	.Fa key
	42	argument
	43	points to an element that matches the one that is searched.
	44	The array's address in memory is denoted by the
	45	.Fa base
	46	argument.
	47	The width of one element (i.e., the size as returned by
	48	.Fn sizeof )
	49	is passed as the
	50	.Fa width
	51	argument.
	52	The number of valid elements contained in the array (not the number of
	53	elements the array has space reserved for) is given in the integer pointed
	54	to by
	55	.Fa nelp .
	56	The
	57	.Fa compar
	58	argument points to a function which compares its two arguments and returns
	59	zero if they are matching, and non-zero otherwise.
	60	.Pp
	61	If no matching element was found in the array,
	62	.Fn lsearch
	63	copies
	64	.Fa key
	65	into the position after the last element and increments the
	66	integer pointed to by
	67	.Fa nelp .
	68	.Sh RETURN VALUES
	69	The
	70	.Fn lsearch
	71	and
	72	.Fn lfind
	73	functions
	74	return a pointer to the first element found.
	75	If no element was found,
	76	.Fn lsearch
	77	returns a pointer to the newly added element, whereas
	78	.Fn lfind
	79	returns
	80	.Dv NULL .
	81	Both functions return
	82	.Dv NULL
	83	if an error occurs.
	84	.Sh SEE ALSO
	85	.Xr bsearch 3 ,
	86	.Xr hsearch 3 ,
	87	.Xr tsearch 3
	88	.Sh HISTORY
	89	The
	90	.Fn lsearch
	91	and
	92	.Fn lfind
	93	functions appeared in
	94	.Bx 4.2 .
	95	In
	96	.Fx 5.0 ,
	97	they reappeared conforming to
	98	.St -p1003.1-2001 .
	99	.Sh STANDARDS
	100	The
	101	.Fn lsearch
	102	and
	103	.Fn lfind
	104	functions conform to
	105	.St -p1003.1-2001 .