How to Determine the Blocking Session for Event: 'cursor: pin S wait on X'

Use this query to determine the Blocking Session for Event: 'cursor: pin S wait on X'

select s.username
, s.sid
, s.serial#
, p.spid pid
, last_call_et
, status
from V$SESSION s
, V$PROCESS p
where s.PADDR = p.ADDR
and sid in (
select to_number(substr(to_char(rawtohex(p2raw)),1,8),'XXXXXXXX') sid
from v$session
where event = 'cursor: pin S wait on X');