When MFX is to be invoked more than once in the same job step, you may need different $ORTPARM DD
control data sets for each invocation. For multiple control data sets,
define each one in the JCL stream, in the desired order, as a disk data set
(or partitioned data set member) with the FREE=CLOSE parameter added.
FREE=CLOSE will cause the first sort $ORTPARM data set to be dynamically
deallocated by the first sort execution, and so forth for each sort
execution. The following example shows sample JCL with two $ORTPARM DD
statements:
Figure 1. Sample Multiple $ORTPARM DD
Statements
Processing will proceed from top to bottom of this $ORTPARM data set list. This sequence must be maintained in the JCL so that the multiple sorts can read the $ORTPARM data sets in the correct order.
Multiple $ORTPARM data sets are available only in a JES2 environment. JES3 does not support the specification of multiple DD statements for the same DDNAME.