1 #include "str.h" 2 str_diff(s,t)3int str_diff(s,t) 4 register char *s; 5 register char *t; 6 { 7 register char x; 8 9 for (;;) { 10 x = *s; if (x != *t) break; if (!x) break; ++s; ++t; 11 x = *s; if (x != *t) break; if (!x) break; ++s; ++t; 12 x = *s; if (x != *t) break; if (!x) break; ++s; ++t; 13 x = *s; if (x != *t) break; if (!x) break; ++s; ++t; 14 } 15 return ((int)(unsigned int)(unsigned char) x) 16 - ((int)(unsigned int)(unsigned char) *t); 17 } 18