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.\"	$OpenBSD: bcmp.3,v 1.11 2014/06/13 02:12:17 matthew Exp $
.\"
.Dd $Mdocdate: June 13 2014 $
.Dt BCMP 3
.Os
.Sh NAME
.Nm bcmp
.Nd compare byte string
.Sh SYNOPSIS
.In string.h
.Ft int
.Fn bcmp "const void *b1" "const void *b2" "size_t len"
.Sh DESCRIPTION
The
.Fn bcmp
function compares byte string
.Fa b1
against byte string
.Fa b2 ,
returning zero if they are identical, non-zero otherwise.
Both strings are assumed to be
.Fa len
bytes long.
Zero-length strings are always identical.
.Pp
The strings may overlap.
.Sh SEE ALSO
.Xr memcmp 3 ,
.Xr strcasecmp 3 ,
.Xr strcmp 3 ,
.Xr strcoll 3 ,
.Xr strxfrm 3 ,
.Xr timingsafe_bcmp 3
.Sh HISTORY
The
.Fn bcmp
function first appeared in
.Bx 4.2 .