Library cache lock - find locking session

1.
select saddr from v$session where sid in (select sid from v$session_wait where event like 'library cache lock');

2. FIND BLOCKER:
SELECT SID,USERNAME,TERMINAL,PROGRAM FROM V$SESSION
WHERE SADDR in
(SELECT KGLLKSES FROM X$KGLLK LOCK_A
WHERE KGLLKREQ = 0
AND EXISTS (SELECT LOCK_B.KGLLKHDL FROM X$KGLLK LOCK_B
WHERE KGLLKSES = 'saddr_from_v$session above' /* BLOCKED SESSION */
AND LOCK_A.KGLLKHDL = LOCK_B.KGLLKHDL
AND KGLLKREQ > 0)
);

3. FIND BLOCKED:
SELECT SID,USERNAME,TERMINAL,PROGRAM FROM V$SESSION
WHERE SADDR in
(SELECT KGLLKSES FROM X$KGLLK LOCK_A
WHERE KGLLKREQ > 0
AND EXISTS (SELECT LOCK_B.KGLLKHDL FROM X$KGLLK LOCK_B
WHERE KGLLKSES = 'saddr_from_v$session above' /* BLOCKING SESSION */
AND LOCK_A.KGLLKHDL = LOCK_B.KGLLKHDL
AND KGLLKREQ = 0)
);