run {
CONFIGURE CONTROLFILE AUTOBACKUP ON;
CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '/dd_oraback/tkprod/%F';
CONFIGURE RETENTION POLICY TO RECOVERY WINDOW OF 22 DAYS;
sql 'alter system archive log current';
delete noprompt obsolete;
crosscheck archivelog all;
delete noprompt expired archivelog all backed up 1 times to disk completed before 'sysdate-2';
backup format '/dd_oraback/tkprod/%d_ARC_%T_%U' archivelog all not backed up 1 times filesperset=1 TAG='tkprod_ARC_13-Dec-11_14:54';
delete noprompt archivelog all backed up 1 times to disk completed before 'sysdate-2';
backup format '/dd_oraback/tkprod/%d_CF_%T_%U' current controlfile TAG='tkprod_CF_13-Dec-11_14:54';
sql 'alter system archive log current';
}

RMAN configuration parameters are:
CONFIGURE RETENTION POLICY TO RECOVERY WINDOW OF 22 DAYS;
CONFIGURE BACKUP OPTIMIZATION ON;
CONFIGURE DEFAULT DEVICE TYPE TO DISK; # default
CONFIGURE CONTROLFILE AUTOBACKUP ON;
CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '/dd_oraback/tkprod/%F';
CONFIGURE DEVICE TYPE DISK PARALLELISM 1 BACKUP TYPE TO BACKUPSET; # default
CONFIGURE DATAFILE BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default
CONFIGURE ARCHIVELOG BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default
CONFIGURE MAXSETSIZE TO UNLIMITED; # default
CONFIGURE ENCRYPTION FOR DATABASE OFF; # default
CONFIGURE ENCRYPTION ALGORITHM 'AES128'; # default
CONFIGURE ARCHIVELOG DELETION POLICY TO NONE; # default
CONFIGURE SNAPSHOT CONTROLFILE NAME TO '/dd_oraback/tkprod/rman/snapcf_tkprod.f';

skipping archive log file /u09/ora_arch/tkprod/arch_1_210433_596995708.arc; already backed up 1 time(s)
skipping archive log file /u09/ora_arch/tkprod/arch_1_210434_596995708.arc; already backed up 1 time(s)
channel ORA_DISK_1: starting archive log backupset
channel ORA_DISK_1: specifying archive log(s) in backup set
input archive log thread=1 sequence=210435 recid=208452 stamp=769792201
channel ORA_DISK_1: starting piece 1 at 13-DEC-2011 15:10:36
channel ORA_DISK_1: finished piece 1 at 13-DEC-2011 15:10:43
piece handle=/dd_oraback/tkprod/TKPROD_ARC_20111213_mcmu467b_1_1 tag=TKPROD_ARC_13-DEC-11_15:09 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:08
channel ORA_DISK_1: starting archive log backupset
channel ORA_DISK_1: specifying archive log(s) in backup set
input archive log thread=1 sequence=210436 recid=208453 stamp=769792234
channel ORA_DISK_1: starting piece 1 at 13-DEC-2011 15:10:44
channel ORA_DISK_1: finished piece 1 at 13-DEC-2011 15:10:47
piece handle=/dd_oraback/tkprod/TKPROD_ARC_20111213_mdmu467j_1_1 tag=TKPROD_ARC_13-DEC-11_15:09 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:04
Finished backup at 13-DEC-2011 15:10:47

Starting Control File and SPFILE Autobackup at 13-DEC-2011 15:10:47
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03009: failure of Control File and SPFILE Autobackup command on ORA_DISK_1 channel at 12/13/2011 15:10:49
ORA-01580: error creating control backup file /dd_oraback/tkprod/snapcf_tkprod.f
ORA-27086: unable to lock file - already in use
SVR4 Error: 22: Invalid argument
Additional information: 9
Additional information: 22

Recovery Manager complete.

ls -al /dd_oraback/tkprod/snapcf_tkprod.f
-rw-r-----   1 oracle   dba      20103168 Dec 13 15:10 /dd_oraback/tkprod/snapcf_tkprod.f