>>-+--------------------------------------+--------------------><
   |        .-,-----------------------.   |   
   |        V                         |   |   
   '-DYNAM(---(--volser--+-------+--)-+-)-'   
                         '-,unit-'            

DYNAM specifies a dynamically allocated volume whose partitioned data sets, if selected, are to be compressed. The volume must be mounted and online. You cannot specify a nonspecific volume serial number using an asterisk (*). Consider using DYNAM instead of DD statements to allocate DASD volumes. This does not appreciably increase run time and permits easier coding of JCL and command input.

volser

Specifies the volume serial number of a DASD volume to be processed.

unit

Specifies the device type of a DASD volume to be processed. This parameter is optional.