usr/src/lib/libc/stdlib/bsearch.3

.\" Copyright (c) 1990 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" %sccs.include.redist.man%
.\"
.\"     @(#)bsearch.3   5.3 (Berkeley) %G%
.\"
.TH BSEARCH 3 ""
.UC 7
.SH NAME
bsearch - binary search of a sorted table
.SH SYNOPSIS
.nf
.ft B
#include <stdlib.h>
.sp
char *
bsearch(const void *key, const void *base,
size_t nmemb, size_t size,
int (*compar) (const void *, const void *));
.ft R
.fi
.SH DESCRIPTION
The
.I bsearch
function searches an array of
.I nmemb
objects, the inital member of which is
pointed to by
.IR base ,
for a member that matches the object pointed to by
.IR key .
The size of each member of the array is specified by
.I size .
.PP
The contents of the array should be in ascending sorted order according
to the comparison function referenced by
.IR compar .
.I Compar
is called with two arguments that point to the
.I key
object and to an array member, in that order, and must return an integer
less than, equal to, or greater than zero if the
.I key
object is considered, respectively, to be less than, equal to, or to
greater than the array member.
.PP
The
.I bsearch
function returns a pointer to a matching member of the array, or a null
pointer if no match is found.
If two members compare as equal, which member is matched is unspecified.
.SH "SEE ALSO"
db(3), lsearch(3), qsort(3)
.SH STANDARDS
.B Bsearch
conforms to ANSI X3.159-1989 (``ANSI C'').