list of files stored in ASM and CURRENTLY NOT OPENED

This is the first example of the results of the execution of the script.  Note it includes all type of files like ARCHIVELOGS, FLASHBACK LOGS, REDOLOGS. Once it has been confirmed the files are not required any more, then they can be deleted using ASMCMD or SQL running the command ALTER DISKGROUP ... DROP FILE '<path>';

set pagesize 0
set linesize 200
col full_alias_path format a80
/*+ ----------------------------------------------------------------
    Query will return all the files stored on ASM but not currenlty
    opened by any database client of the diskgroups
    ordered by group number, file type
    ---------------------------------------------------------------*/

select * from (
/*+ -----------------------------------------------------------------
    1st branch returns all the files stored on ASM
    -----------------------------------------------------------------*/
select  x.gnum,x.filnum,x.full_alias_path,f.ftype from (
SELECT gnum,filnum,concat('+'||gname, sys_connect_by_path(aname, '/')) full_alias_path
FROM (SELECT g.name gname, a.parent_index pindex, a.name aname,
            a.reference_index rindex,a.group_number gnum,a.file_number filnum
      FROM v$asm_alias a, v$asm_diskgroup g
      WHERE a.group_number = g.group_number)
START WITH (mod(pindex, power(2, 24))) = 0 CONNECT BY PRIOR rindex = pindex) x,
(select group_number gnum,file_number filnum, type ftype from v$asm_file order by group_number,file_number) f
where x.filnum != 4294967295
and x.gnum=f.gnum and x.filnum=f.filnum
MINUS
/*+ --------------------------------------------------------------
    2nd branch returns all the files stored on ASM
    and currently opened by any database client of the diskgroups
    -----------------------------------------------------------------*/
select x.gnum,x.filnum,x.full_alias_path,f.ftype
from ( select id1 gnum,id2 filnum from v$lock where type='FA' and (lmode=4 or lmode=2)) l,
(
SELECT gnum,filnum,concat('+'||gname, sys_connect_by_path(aname, '/')) full_alias_path
FROM (SELECT g.name gname, a.parent_index pindex, a.name aname,
            a.reference_index rindex,a.group_number gnum,a.file_number filnum
      FROM v$asm_alias a, v$asm_diskgroup g
      WHERE a.group_number = g.group_number)
START WITH (mod(pindex, power(2, 24))) = 0 CONNECT BY PRIOR rindex = pindex
) x,
(select group_number gnum,file_number filnum, type ftype from v$asm_file order by group_number,file_number) f
where x.filnum != 4294967295 and
x.gnum=l.gnum
and x.filnum=l.filnum
and x.gnum=f.gnum and x.filnum=f.filnum) q
order  by q.gnum,q.ftype
;