Specify a backward reference to an earlier DD statement. The
referenced DD statement cannot name a cataloged data set or refer
to another DD statement.
*.ddname
Specifies the ddname of an earlier DD statement in the same
step.
*.stepname.ddname
Specifies the ddname of a DD statement in an earlier step, stepname,
in the same job.
*.stepname.procstepname.ddname
Specifies the ddname of a DD statement in a cataloged or in-stream
procedure called by an earlier job step. Stepname is the name of
the job step that calls the procedure and procstepname is the name
of the procedure step that contains the DD statement.