Using the CHANGEDATASET COPYFROM subcommand

For a target data set that has already been created, a tape copy application can use the CHANGEDATASET COPYFROM subcommand to copy all applicable attributes from the source data set to the target data set. DFSMSrmm determines which attributes are to be copied. Retention of the source data set can be specifically set. Retention of the target volumes and data sets can be selected at the volume set level, and even switched between VRSEL and EXPDT retention methods.

Using the CHANGEDATASET COPYFROM subcommand, you can ensure that all applicable data set attributes are copied and avoid using multiple RMM subcommands to modify only some of the attributes

The CHANGEDATASET COPYFROM subcommand identifies a single volume data set or any part of a multivolume data set. Validation is done to ensure that the source and target data sets have the same recording format and record length. You use the CHANGEDATASET subcommand once for each target data set record. For multivolume data sets, this means that you must issue the subcommand once for each volume the target data set is written on.

For example, data set MIKE.EXAMPLE is the only file on volume MW0001 and is copied from a physical tape into a virtual tape system. It is a single input volume, but now multiple output volumes VT0001, VT0002, and VT0003. When the data has been copied, you would issue the following commands to copy the input data set record attributes to each of the output data set records:

RMM CD 'MIKE.EXAMPLE' VOLUME(VT0001) COPYFROM(VOLUME(MW0001))
RMM CD 'MIKE.EXAMPLE' VOLUME(VT0002) COPYFROM(VOLUME(MW0001))
RMM CD 'MIKE.EXAMPLE' VOLUME(VT0003) COPYFROM(VOLUME(MW0001))

When you use the COPYFROM subcommand operand, the last change information of the target data set is also updated during command processing to reflect that the command was processed.

Refer to CHANGEDATASET: Changing data set information for details on using the COPYFROM operand.