Enterprise Cobol V6 - Alternative to CEEGTST, CEEFRST and CEECZST for UNBOUNDED ODO tables

Enterprise Cobol V6 compiler brings the ALLOCATE and FREE statements for managing the memory associated with a structure defined in the LINKAGE SECTION.

These statements are not directly applicable to an UNBOUNDED table but can allocate and free memory through a pointer variable and an arithmetic expression, and the address of the UNBOUDED table can be fixed by this pointer variable :
- ALLOCATE numeric-expression CHARACTERS RETURNING pointer-variable
- SET ADDRESS OF unbounded-table TO pointer-variable

However, it lacks a statement to resize the previously allocated area to respond to an expansion or a reduction of the table without loss of data already stored in the UNBOUDED table.

It remains possible to allocate a new memory area by ALLOCATE, MOVE the structure of the unbounded table to this new area, and then release the previously allocated memory area by FREE, but this more complex treatments than a RESIZE.

Before Cobol V6, we use the Language Environment functions to manage dynamically allocated memory:
-CEEGTST: comparable to the ALLOCATE Cobol V6 statement
-CEEFRST: comparable to the FREE Cobol V6 statement
-CEECZST: no equivalent Cobol V6 statement

Note that CEECZST can change the address of the allocated memory area and it is then necessary to reattach the address of the structure in the LINKAGE SECTION.

It would be useful to have a Cobol statement to change the size (grow or shrink) of an already allocated memory area, with an option to keep the already loaded data.
For example:

RESIZE pointer-variable FOR numeric-expression CHARACTERS [NO] PRESERVE