byte_diff.c


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/* Public domain. */

#include "byte.h"

int byte_diff(s,n,t)
register char *s;
register unsigned int n;
register char *t;
{
  for (;;) {
    if (!n) return 0;
    if (*s != *t) break;
    ++s; ++t; --n;
    if (!n) return 0;
    if (*s != *t) break;
    ++s; ++t; --n;
    if (!n) return 0;
    if (*s != *t) break;
    ++s; ++t; --n;
    if (!n) return 0;
    if (*s != *t) break;
    ++s; ++t; --n;
  }
  return ((int)(unsigned int)(unsigned char) *s)
       - ((int)(unsigned int)(unsigned char) *t);
}