NetBSD/lib/libc/stdlib/lsearch.3

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.\"     from: @(#)lsearch.3	8.1 (Berkeley) 6/4/93
.\"	$NetBSD: lsearch.3,v 1.3 2005/07/12 08:28:42 wiz Exp $
.\"
.Dd July 6, 2005
.Dt LSEARCH 3
.Os
.Sh NAME
.Nm lsearch ,
.Nm lfind
.Nd linear searching routines
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In search.h
.Ft void *
.Fn lsearch "const void *key" "void *base" "size_t *nelp" "size_t width" "int (*compar)(const void *, const void *)"
.Ft void *
.Fn lfind "const void *key" "const void *base" "size_t *nelp" "size_t width" "int (*compar)(const void *, const void *)"
.Sh DESCRIPTION
The functions
.Fn lsearch ,
and
.Fn lfind
provide basic linear searching functionality.
.Pp
.Fa base
is the pointer to the beginning of an array.
The argument
.Fa nelp
is the current number of elements in the array, where each element
is
.Fa width
bytes long.
The
.Fa compar
argument points to a function which compares its two arguments and returns
zero if they are matching, and non-zero otherwise.
.Pp
The
.Fn lsearch
and
.Fn lfind
functions
return a pointer into the array referenced by
.Fa base
where
.Fa key
is located.
If
.Fa key
does not exist,
.Fn lfind
will return a null pointer and
.Fn lsearch
will add it to the array.
When an element is added to the array by
.Fn lsearch
the location referenced by the argument
.Fa nelp
is incremented by one.
.Sh SEE ALSO
.Xr bsearch 3 ,
.Xr db 3
.Sh STANDARDS
The
.Fn lsearch
and
.Fn lfind
functions conform to
.St -p1003.1-2001 .