How to use show command in rman?

Show * :-   use to display the current configuration of rman.

[oracle@wasiq d01]$ rman

Recovery Manager: Release 11.2.0.1.0 - Production on Fri Dec 27 21:43:39 2013

Copyright (c) 1982, 2009, Oracle and/or its affiliates.  All rights reserved.

RMAN> connect target /;

connected to target database: PROD (DBID=246965557)

using target database control file instead of recovery catalog

RMAN> SHOW RETENTION POLICY;

RMAN configuration parameters for database with db_unique_name PROD are:

CONFIGURE RETENTION POLICY TO REDUNDANCY 2;

RMAN> SHOW DEVICE TYPE;

RMAN configuration parameters for database with db_unique_name PROD are:

CONFIGURE DEVICE TYPE DISK PARALLELISM 1 BACKUP TYPE TO BACKUPSET;

RMAN> SHOW CHANNEL;

RMAN configuration parameters for database with db_unique_name PROD are:

RMAN configuration has no stored or default parameters

RMAN> SHOW MAXSETSIZE;

RMAN configuration parameters for database with db_unique_name PROD are:

CONFIGURE MAXSETSIZE TO UNLIMITED;

RMAN> CONFIGURE MAXSETSIZE TO 500m;

old RMAN configuration parameters:

CONFIGURE MAXSETSIZE TO UNLIMITED;

new RMAN configuration parameters:

CONFIGURE MAXSETSIZE TO 500 M;

new RMAN configuration parameters are successfully stored

RMAN> SHOW MAXSETSIZE;

RMAN configuration parameters for database with db_unique_name PROD are:

CONFIGURE MAXSETSIZE TO 500 M;

RMAN> SHOW BACKUP OPTIMIZATION;

RMAN configuration parameters for database with db_unique_name PROD are:

CONFIGURE BACKUP OPTIMIZATION ON;

RMAN> SHOW SNAPSHOT CONTROLFILE NAME;

RMAN configuration parameters for database with db_unique_name PROD are:

CONFIGURE SNAPSHOT CONTROLFILE NAME TO '/d01/oracle/product/11.2.0/dbs/snapcf_prod.f';

RMAN> SHOW CONTROLFILE AUTOBACKUP;

RMAN configuration parameters for database with db_unique_name PROD are:

CONFIGURE CONTROLFILE AUTOBACKUP ON;

RMAN> SHOW COMPRESSION ALGORITHM;

RMAN configuration parameters for database with db_unique_name PROD are:

CONFIGURE COMPRESSION ALGORITHM 'BASIC' AS OF RELEASE 'DEFAULT' OPTIMIZE FOR LOAD TRUE;

RMAN> SHOW ENCRYPTION ALGORITHM;

RMAN configuration parameters for database with db_unique_name PROD are:

CONFIGURE ENCRYPTION ALGORITHM 'AES128';

RMAN>