1.\" Copyright (c) 1990, 1991 The Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" Chris Torek. 6.\" %sccs.include.redist.man% 7.\" 8.\" @(#)memcmp.3 5.4 (Berkeley) 04/19/91 9.\" 10.Dd 11.Dt MEMCMP 3 12.Os 13.Sh NAME 14.Nm memcmp 15.Nd compare byte string 16.Sh SYNOPSIS 17.Fd #include <string.h> 18.Ft int 19.Fn memcmp "const void *b1" "const void *b2" "size_t len" 20.Sh DESCRIPTION 21The 22.Fn memcmp 23function 24compares byte string 25.Fa b1 26against byte string 27.Fa b2 . 28Both strings are assumed to be 29.Fa len 30bytes long. 31.Sh RETURN VALUES 32The 33.Fn memcmp 34function 35returns zero if the the two strings are identical, 36otherwise returns the difference between the first two differing bytes 37(treated as unsigned char values, so that 38.Sq Li \e200 39is greater than 40.Sq Li \&\e0 , 41for example). 42Zero-length strings are always identical. 43.Sh SEE ALSO 44.Xr bcmp 3 , 45.Xr strcasecmp 3 , 46.Xr strcmp 3 , 47.Xr strcoll 3 , 48.Xr strxfrm 3 49.Sh STANDARDS 50The 51.Fn memcmp 52function 53conforms to 54.St -ansiC . 55