rem: DBG("JABBER: s_lock_at: <%d>\n", i);
add: DBG("XJAB: s_lock_at: <%d>\n", i);
context: static inline int s_lock_at(smart_lock *s, int i){	DBG("JABBER: s_lock_at: <%d>\n", i);#ifdef FAST_LOCK	get_lock(&s[i]);	return 0;#else	return change_semaphore( &s[i], -1 );#endif}