OS Simulation › DMSTVI Exit › Writing Data Sets to Tape

Writing Data Sets to Tape

The example EXECs in this section show how to write a primary data set, a new generation of a data set, and a secondary data set to tape.

Whenever you read or write data sets to tape, you must specify the sequence number of the data set on the tape on both the CMS FILEDEF and LABELDEF commands. CMS and CA VM:Tape require the sequence number to mount and position the tape correctly. If you specify a different file sequence number on the SL parameter of the FILEDEF command from the one you specify on the FSEQ parameter on the LABELDEF command, the number on the SL parameter supersedes the number on the FSEQ parameter.