The CICS-supplied sample program, DFH$CUS1, illustrates how DFHCSDUP can be invoked from a user program. It is written as a command processor (CP) for execution under the TSO/E operating system.
Note that DFH$CUS1 uses different DCB and ACB names from those normally used by DFHCSDUP. Ensure that these are allocated before running the program under TSO/E.