ref: bd41c3ee99a819ae92887538049cdef0ad482763
dir: /lib/c/memcmp.c/
#include <string.h>
#undef memcmp
int
memcmp(const void *s1, const void *s2, size_t n)
{
	const char *s = s1;
	const char *t = s2;
	for ( ; n > 0 && *s == *t; --n)
		++s, ++t;
	return (n > 0) ? *(unsigned char *) s - *(unsigned char *) t : 0;
}