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[SHANKS]

How do you dynamically define the size of array("occurs ") during runtime in COBOL programs ?

[dbzTHEdinosauer]

you can't.

What you can do, is GETMAIN (or use whatever LE -Language Environment service is available on your OPSYS and acquire additional runtime memory) and assign a table definition to the new area, but a COBOL Table defined in working storage has only one size, the max occurs.

A COBOL Table defined with ODO (occurs depending on) will be assigned the size of the max occurs; though for purposes of Statements such a SEARCH, using the ODO will cause the Search to only look at the number of items declared by the value contained in the ODO object - the counter.
_________________
Dick Brenholtz
American living in Varel, Germany

[blitz2]

[dbzTHEdinosauer]

As a follow-up to Blitz's excellent post:

Unlike C, VB, JAVA & REXX, where you can just keep on dynamically adding 'occurs', COBOL Tables are based on contiguous memory - it is required by the code to address each item.

In the C, VB & JAVA languages and REXX Scripts, the table items are not required to be in contiguous memory - the concept of contiguous memory does not belong to those languages - which is why you can, continuously, dynamically allocate 'occurs' during runtime.

In COBOL, once you have dynamically allocated additional memory (GETMAIN in CICS, LE memory acquisition in Batch), that memory is one (1) table definition. If you then acquire more memory, the second and subsequent memory allocations have to be addressed as separate tables. i.e. you can not 'extend' a COBOL Table with a second dynamic memory allocation.
_________________
Dick Brenholtz
American living in Varel, Germany

[dz]

Actually, this is possible to do, with caveats. I did something similar in CICS program via GETMAIN, and I'm sure could be done in batch using CEEGTST.
Here is what I did:
1) COBOL OCCURS has to be 1 and counld reside in the LINKAGE or WS
2) Compile ALWAYS with NOSSRANGE
3) Allocate Max memory by calculating number of bytes = <occurs element length> * <Max number of elements>
4) Assign address of newly allocated memory to array in linkage
5) Redefine the Pointer as follows:
05 LINK-ADDRSS USAGE IS POINTER.
05 LINK-ADDRSS-RE REDEFINES LINK-ADDRSS PIC S9(08) COMP.
5) Walk the array (up to <Max number of elements>) by increasing the address in LINK-ADDRSS-RE by simple addition of the <occurs element length>. Reset the address of COBOL array to point to LINK-ADDRSS
6) ALWAYS use index of 1 when referencing array element
7) Good idea to save your original address, for FREEMAIN (or CEEFRST) purposes

[DaveyC]

[dbzTHEdinosauer]

DaveyC,

thanks for the correction, and education.
dick
_________________
Dick Brenholtz
American living in Varel, Germany

[jsharon1248]

I'll go one step further on dz's excellent recommendation to aquire storage using LE service CEEGTST. I use CEEGTST in COBOL to create linked lists. I'd recommend using the linked list rather than bothering with tables and increasing displacements. It's fairly straightforward.