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freebsd/lib/libc/string/bcmp.3
Xin LI 854023f054 Add timingsafe_bcmp and timingsafe_memcmp.
Obtained from:	OpenBSD
Reviewed by:	trasz
MFC after:	1 month
Differential Revision:	https://reviews.freebsd.org/D7280
2016-08-14 23:38:50 +00:00

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2.5 KiB
Groff

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.\" @(#)bcmp.3 8.1 (Berkeley) 6/4/93
.\" $FreeBSD$
.\"
.Dd August 15, 2016
.Dt BCMP 3
.Os
.Sh NAME
.Nm bcmp
.Nd compare byte string
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In strings.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
A
.Fn bcmp
function first appeared in
.Bx 4.2 .
Its prototype existed previously in
.In string.h
before it was moved to
.In strings.h
for
.St -p1003.1-2001
compliance.