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whizkid79 · Beginner Joined: 29 Sep 2004 Posts: 53 Topics: 14

Hi,

I tried passing a pointer from a PL1 program to a COBOL program. But when I try passing a pointer from a COBOL program to a PL1 program, its giveing protection exception error. The same error comes when i pass a pointer from a COBOL program to another COBOL program.

Passing pointer from COBOL pgm A to COBOL pgm B
I'm a passing a pointer to character field having value 'ASD' from pgm A to pgm B. I get the value in pgm B and i try to overwrite that with 'SDF' and pass it back to pgm B. But in the statement

MikeBaker · Beginner Joined: 04 May 2004 Posts: 96 Topics: 9

Whizkid,

Surely "TEST-CHAR" is not your Pointer? Because you don't set pointers like that. Yeah you probably would get a S0C4 if you tried to set a pointer like that. The receiving program will also need to have the Pointer defined as such inside the Linkage section.

Although having never done what you ask, it seems quite feasible.

whizkid79 · Beginner Joined: 29 Sep 2004 Posts: 53 Topics: 14

This is the code of calling program:

Bithead · Posted: Fri Dec 10, 2004 11:52 am Post subject:

Change

CALL 'TSTCB2' USING TEST1-PTR

to

CALL 'TSTCB2' USING TEST1-PTR, TEST-COB

whizkid79 · Beginner Joined: 29 Sep 2004 Posts: 53 Topics: 14

This didn't work. Moreover if i'm passing the structure also, then there is no use of passing a pointer. The similar code worked well when a pointer is passed from a PL1 program to TSTCB2.

Bithead · Posted: Mon Dec 13, 2004 12:19 pm Post subject:

I missed the REDEFINES.

What are you trying to achieve in passing the POINTER?

Mike Chantrey · Posted: Mon Dec 13, 2004 12:51 pm Post subject:

The redefines in TSTCB1 has the effect of giving the pointer a value equal to the *contents* of the first 4 bytes of TEST-COB - i.e. "ABC ". This is not a valid address.
You want the pointer to contain the address of this data, not the contents, so the pointer should *not* be a redefines of TEST-COB, it should be a seperate data area.

So remove the REDEFINES in TSTCB1, and then add this code before the CALL:

SET TEST1-PTR TO ADDRESS OF TEST-COB.

Note that if you are using the unsupported COBOL II compiler that this will not work since you can't use SET like this with working storage items, only linkage section items.
Later versions of COBOL will be OK.

whizkid79 · Beginner Joined: 29 Sep 2004 Posts: 53 Topics: 14

I made the changes. The compile was good. But the run abended because of S0C4 (protection exception).

Is there anything like pointers cannot be passed among cobol programs?

Bithead · Posted: Tue Dec 14, 2004 11:29 am Post subject:

Try changing

PROCEDURE DIVISION USING TEST-PTR.

to

PROCEDURE DIVISION USING TEST-COB TEST-PTR.

Change the 01 TEST2-COB variable name in the LINKAGE SECTION of the subroutine to TEST-COB to avoid reference conflicts.

whizkid79 · Beginner Joined: 29 Sep 2004 Posts: 53 Topics: 14

I've tried out all these options, but its still giving S0C4 abend. Sad

Can anyone give a working cobol program that uses pointer?

Bithead · Posted: Wed Dec 15, 2004 12:35 pm Post subject:

I just tested the program and it works for me. Please post your revised code.

whizkid79 · Beginner Joined: 29 Sep 2004 Posts: 53 Topics: 14

But here, you're passing the structure also. I want to pass only the pointer. If i'm passing the structure then there is no use of a pointer.

Bithead · Posted: Thu Dec 16, 2004 9:06 am Post subject:

You cannot reference the working storage of the calling program from the subroutine unless you place it in the linkage section and pass a reference to it (CALL ... USING ..) or by using the EXTERNAL clause. Note: the USING statement actually passes the address of the 01 level, not the data itself.

Any attempt to do so will generate a protection exception (S0C4).

whizkid79 · Beginner Joined: 29 Sep 2004 Posts: 53 Topics: 14

Thanks for the info. So to summerize, there is no use of using pointers among cobol programs.

Bithead · Posted: Mon Dec 20, 2004 12:19 pm Post subject:

I am sure there are some uses but in this example it should not be used.