There is a call to IDMSIN01 to change the SYSCTL DD name to a different name from the default SYSCTL. How does this work? Is there also a call to find out the current SYSCTL DD Name?
If you issue a BIND RUN UNIT it will first use the default of SYSCTL. If you then change the SYSCTL DD name by calling IDMSIN01 and issue another BIND RUN UNIT it will use the new SYSTCL name.
There is no function call to get the current SYSCTL DD name. The default is SYSCTL unless you call IDMSIN01 to change it. The other way to change it is to create an IDMSOPTI with a different SYSCTL name. To find out the current SYSCTL name you could write an assembler program to look at field CSADSCTL in the CSA. It will either contain blanks (for the default name SYSCTL) or the name it was changed to by calling IDMSIN01.
Callable Services Guide section IDMSIN01
TEC600625 Error handling in IDMSIN01 calls from assembler