rem: struct idlist *list = uidlist;
add: struct idlist *list;  if (uid == 0) return 0;
context: static uid_t match_uid(uid_t uid){	static uid_t last_in, last_out;	struct idlist *list = uidlist;	if (uid == last_in)		return last_out;	last_in = uid;	while (list) {		if (list->id == (int)uid) {			last_out = (uid_t)list->id2;			return last_out;		}		list = list->next;	}	last_out = uid;	return last_out;}