Linkage Section in CICS program

laddhavishal · New User Joined: 03 Mar 2010 Posts: 3 Location: Mumbai

I have a 4 set of programs say A, B, C & D. Program A is a COBOL FSA program which invokes B which is a pure CICS program using LINK command & passes the data using WS section of A.

B in turn invokes C which is a COBOL FSA(a propreitry arhitecutre) program. Data is transferred from B to C via VCOM(similar to DFHCOMMAREA for CIC & is present in linkage section of both calling & called pgm). VCOM present in linkage of both B & C.

B also invokes D which is an CICS MQ program. Data is transferred using another WS section of B & received in D in DFHCOMMAREA in linkage. No VCOM present here.

So in summary we have following:
1. A passes data to B via WS var whic goes to DFHCOMMAREA of B.
2. B has DFHCOMMAREA coming from A & VCOM to be passed to C. Both are present in linkage section of B at diferent 01 levels. B also passes data to D via WS vars.
3. C is a COBOL FSA program which has VCOM in its linkage section to receive data from B.
4. D is a MQ CICS program which has DFHCOMMAREA in its linkage section to receive data from B.

Now my question is when my program B is being executed & it calls C & LINKS to D for further processing & then returns back, is it possible that the data in linkage area of program B may interfere anywhere with each other as C & D has only 1 area each in it.

Please let me know as I need to know this ASAP before my programs go live into production this weekend.

Let me know if above sounds confusing & need more explaination. Thanks in advance to all for help.

Regards,
Vishal Laddha

enrico-sorichetti · Posted: Wed Mar 03, 2010 2:49 pm

laddhavishal · New User Joined: 03 Mar 2010 Posts: 3 Location: Mumbai

The testing has gone fine but we had a problem earlier where hecode worked in testing region but not in production. It was just that during a peer review we had some doubts raised over such a design & hence thought of putting it up to be sure that design will not have long standing impacts after going in production.

In our earlier case ,we had the program B itself as a MQ CICS program calling a COBOL FSA program. It tested fine till UAT but bombed in production & we realised that this is not allowed.

We have now removed the MQ part from B & created a new pgm D to do the MQ processing & link to it from B when required. B is now a CICS program with no MQ.

I do realise that ppl will repond when theyhave time. I just highlighted the time constraint to get quick replies if possible by anyone understanding my urgency.

Thanks

Binop B · Posted: Wed Mar 03, 2010 3:50 pm

Hi Vishal,

Please note that I have no idea what FSA COBOL program is or how different VCOM is from DFHCOMMAREA. Assuming it to basic COBOL and DFHCOMMAREA respectively....

laddhavishal · New User Joined: 03 Mar 2010 Posts: 3 Location: Mumbai

I will try to make things simpler here. Lets forget for now what FSA COBOL is. This is how the programs look like
PGM A
WS Section
WS-A

Linkage Section
01 Link-AA

PGM B
WS section
WS-B

Linkage Section
01 LINK BA
01 LINK BB

PGM C
Linkage Section
01 LINK CA

PGM D
Linkage Section
01 LINK DA

Now summary of calls is as below:
1. PGM A LINKS to PGM B & passes WS-A. PGM B receives this in say LINK BA.
2. PGM B CALLS to PGM C & passes LINK BB. PGM C receives it in LINK CA.
3. PGM B LINKS to PGM D & passes WS-B. PGM D receives it in LINK DA.

Now will there be any issue in B since it has 2 major linkage vars in it whereas the called pgms has only 1.

Here the basis of design is the below assumption.
1. Since B is calling C, hence DFHCOMMAREA should not come into picture & only VCOM or LINK BB to LINK CA should come into picture.
2. Also since B LINKS to D, VCOM should not come into picture & only DFHCOMMAREA should come into picture.

Thanks to all for your help & guidance.

Binop B · Posted: Wed Mar 03, 2010 5:05 pm

Hi Vishal,

What i was pointing out is ....

As per my understanding, the LINK BB you have declared is in LINKAGE section basically means no memory is acquired but only referenced.. When u access these fields most likely you should get an ASRA abend unless memory is acquired...

A snapshot from the manuals for your reference ...

Earl Haigh · Active User Joined: 25 Jul 2006 Posts: 475

If you've tested your recent changes, then whats the problem ?

Robert Sample · Posted: Thu Mar 04, 2010 4:41 am

As your question is stated, you are asking about a non-issue. Programs called by program B have access to whatever data is passed via the call mechanism -- whether that is one 01 level, two 01 levels, or thirty-seven 01 levels. The number doesn't matter as long as there is addressability to the memory.

And, as Binop B said, that is where your problem is. Unless you are doing something to establish memory for your LINK-BB 01 level in program B (such as using EXEC CICS GETMAIN and SET ADDRESS), any references to any byte of LINK-BB (whether in program B, or C, or D, or A, or any other program) will either produce unexpected results or cause a storage exception and transaction abend. From the COBOL Language Reference manual section 5.1.4 on Linkage Section: