#include "case.h"int case_diffb(s,len,t)register char *s;unsigned int len;register char *t;{  register unsigned char x;  register unsigned char y;  while (len > 0) {    --len;    x = *s++ - 'A';    if (x <= 'Z' - 'A') x += 'a'; else x += 'A';    y = *t++ - 'A';    if (y <= 'Z' - 'A') y += 'a'; else y += 'A';    if (x != y)      return ((int)(unsigned int) x) - ((int)(unsigned int) y);  }  return 0;}