Using GDGs

AR/CTL supports the use of generation data groups (GDGs) for input and output sequential data sets. The specification of generation numbers does not change for AR/CTL.

If you use generation number +1 in a step at the start of a job and specify restart at a later step in the same job, then you must refer to the output data set with the same generation number +1. If you execute the restart job step in a different job, then you must refer to the output data set with generation number 0.