1.\" Copyright (c) 1990, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" Chris Torek. 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" @(#)bcmp.3 8.1 (Berkeley) 6/4/93 31.\" 32.Dd August 15, 2016 33.Dt BCMP 3 34.Os 35.Sh NAME 36.Nm bcmp 37.Nd compare byte string 38.Sh LIBRARY 39.Lb libc 40.Sh SYNOPSIS 41.In strings.h 42.Ft int 43.Fn bcmp "const void *b1" "const void *b2" "size_t len" 44.Sh DESCRIPTION 45The 46.Fn bcmp 47function 48compares byte string 49.Fa b1 50against byte string 51.Fa b2 , 52returning zero if they are identical, non-zero otherwise. 53Both strings are assumed to be 54.Fa len 55bytes long. 56Zero-length strings are always identical. 57.Pp 58The strings may overlap. 59.Sh SEE ALSO 60.Xr memcmp 3 , 61.Xr strcasecmp 3 , 62.Xr strcmp 3 , 63.Xr strcoll 3 , 64.Xr strxfrm 3 , 65.Xr timingsafe_bcmp 3 66.Sh HISTORY 67A 68.Fn bcmp 69function first appeared in 70.Bx 4.2 . 71Its prototype existed previously in 72.In string.h 73before it was moved to 74.In strings.h 75for 76.St -p1003.1-2001 77compliance. 78