A tape copy application can use the EDG_EXIT100 installation exit to copy the data set attributes from the original to the copy during OPEN processing. In the EDG_EXIT100 installation exit you can specify the data set details for the source data set from which attributes should be copied.

1. Modify your tape copy application to exploit use of EDG_EXIT100:
   1. Verify that EDG_EXIT100 is active
   2. Activate your exit module
   3. Copy the tape data sets and communicate your processing to your exit module
   4. When all copies are completed or as processing progresses successfully you can update the source data sets and volumes to set specific retention methods, expiration dates, or release volumes that are no longer required.
   5. Deactivate your exit module
2. Create your EDG_EXIT100 exit module.

   You must perform these tasks:

   1. Ensure your exit module only performs your required processing when your copy application is running and data set attributes are to be copied.
   2. Only perform processing during OPEN when PL100_CAN_COPYFROM is B'1'. The following EDGPL100 parameter list fields must be set:

      PL100_SET_COPYFROM
      PL100_COPYFROM_DSN
      PL100_COPYFROM_VOLSER
      PL100_COPYFROM_DSEQ
      PL100_COPYFROM_OWNER This is the only optional field.

      The specified owner is used for the first file on the first volume of a multivolume set, and will be propagated by DFSMSrmm during EOV to any additional volumes in the set. The owner is optional. If not specified, DFSMSrmm uses the RACF user ID of the copy application at the time the tape data set is copied.
   3. Make any other changes required such as setting or clearing the EXPDT You can consider also exploitation of the ability of the exit to select either VRSEL or EXPDT retention method for the target volume and whether to exclude the target data sets from VRSEL processing. If you do not set the retention method for the target volume in the EDG_EXIT100 installation exit, DFSMSrmm uses the default retention method specified by the current parmlib OPTION RETENTIONMETHOD.
3. Update your copy application packaging to ship updated and new parts
4. No activation within DFSMSrmm is required, as all required processing, such as use of CSVDYNEX to activate your exit module, is performed by the tape copy application.
5. Run the tape copy application.
   Note: It is your responsibility to provide the correct source data set details. If you pass the wrong source COPYFROM data set details, one of the follow applies:

   1. DFSMSrmm ignores your request if you do not provide valid values for:

      PL100_COPYFROM_DSN,
      PL100_COPYFROM_VOLSER, and
      PL100_COPYFROM_DSEQ

   2. If the data set record is not already defined in the DFSMSrmm CDS, processing continues, but WTO EDG4063I is issued to the job log and the system log.
   3. If the data set record is found, all relevant attributes are copied. In all cases, you can always complete processing or correct processing using the CHANGEDATASET subcommand with COPYFROM specifying the correct source data set record.

If the tape copy application uses this interface, there is no need to use the CHANGEDATASET COPYFROM subcommand. However, at the end of the copy, the application must consider and handle any appropriate retention changes for the source data sets and volumes.

For best results you should ensure that the retention method of the new tape volume set matches that of the original. When data set attributes are copied all existing VRSEL related attributes are copied and so, as long as the new data set is on a volume set with the VRSEL retention method you can expect the same results as for the original data set. When both original and new data is VRSEL managed the VRSELEXCLUDE attribute is copied.

If you plan to switch from VRSEL managed original data sets to EXPDT managed new data sets, you must ensure that the expiration date or retention period is set appropriately for each new data set.