CICS COBOL Driver program calling Natural Subroutine under CICS

[bswami71]

My query is very specific to Mainframe CICS & Natural Platform. I have a requirement where the first program invoked by my CICS transaction is a COBOL Driver Program and it prepares some parameters to call a Natural Subroutine in CICS. I have looked at the manuals and see that I need to prepare a 132 byte PARM-AREA by invoking NCIXCPRM module passing subroutine name and parameters and further use the PARM-AREA as COMMAREA to LINK to NCIXCALL. Does this solution work? My queries is around who sets up Natural Session to invoke the subroutine under as my CICS transaction is starting my COBOL driver program as the first program. I would appreciate if any one can share their thoughts on feasibility and any sample programs

[Douglas_Kelly]

This topic is covered in the NAT932 documentation at Natural 3GL CALLNAT Interface - Usage, Examples

As noted in the documentation, the CICS transaction must start Natural, which runs a program (that you supply) which invokes your COBOL “driver program”. NCIXCALL is called with a LINK after NCIXCPRM is called to set up the parameter list. The Natural object to be called is a specific module type “subprogram” (invoked by other Natural programs with CALLNAT) - not “subroutine” nor “program”.

[bswami71]

Thanks. I saw the example and if it is must for a CICS transaction to start Natural which runs a Simple Natural program like CALLCOB then CALLCOB will be driver(or first program initiated bythe transaction) and not my COBOL program.. I saw this pattern and I thought is it possible to have COBPGM directly as the first program(driver) mapped to transaction and then do the NCIXCALL & NCIXCPRM. I assume that design pattern is not allowed. It should always be to start Natural, invoke a CALLCOB kind of Natural program and then go out to my COBOL program and come back in with the required subprogram call.