1 typedef unsigned char u_char; 2 3 int strcasecmp(s1,s2)4strcasecmp(s1, s2) 5 const char *s1, *s2; 6 { 7 register const u_char 8 *us1 = (const u_char *)s1, 9 *us2 = (const u_char *)s2; 10 11 while (tolower(*us1) == tolower(*us2++)) 12 if (*us1++ == '\0') 13 return (0); 14 return (tolower(*us1) - tolower(*--us2)); 15 } 16