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/* Copyright (C) 2000 MySQL AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/* memcmp(lhs, rhs, len)
compares the two memory areas lhs[0..len-1] ?? rhs[0..len-1]. It
returns an integer less than, equal to, or greater than 0 according
as lhs[-] is lexicographically less than, equal to, or greater than
rhs[-]. Note that this is not at all the same as bcmp, which tells
you *where* the difference is but not what.
Note: suppose we have int x, y; then memcmp(&x, &y, sizeof x) need
not bear any relation to x-y. This is because byte order is machine
dependent, and also, some machines have integer representations that
are shorter than a machine word and two equal integers might have
different values in the spare bits. On a ones complement machine,
-0 == 0, but the bit patterns are different.
*/
#include "strings.h"
#if !defined(HAVE_MEMCPY)
int memcmp(lhs, rhs, len)
register char *lhs, *rhs;
register int len;
{
while (--len >= 0)
if (*lhs++ != *rhs++) return (uchar) lhs[-1] - (uchar) rhs[-1];
return 0;
}
#endif
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