RMAN duplication Process

 Hi,

Iam trying to understand  the RMAN duplication process.  After the recovery step is done, it executes the catalog the datafile copy.... So I would like to understand as what it is trying do as part of the "catalog clone datafilecopy".).. 

Please provide some insight on this one.

Thank you for your help..

contents of Memory Script:
{
set newname for tempfile 1 to
"C:\ORACLE\ORADATA\CLONE\DUPLICAT\DATAFILE\O1_MF_TEMP_1P47MLKR_.TMP";
switch clone tempfile all;
catalog clone datafilecopy "C:\ORACLE\ORADATA\CLONE\DUPLICAT\DATAFILE\O1_MF_USERS_16_1YYG2S9N_.DBF";
catalog clone datafilecopy "C:\ORACLE\ORADATA\CLONE\DUPLICAT\DATAFILE\O1_MF_SYSAUX_1YYG2T33_.DBF";