The IDMS cobol pre-compiler, IDMSDMLC, has an EXEC parm which can be either 1, 2 or 85.
What is the purpose of this parameter?
Release : All supported releases.
Component : IDMS/DB
The COBOL= parameter influences how the pre-compiler expands IDMS DML statements according to the version of Cobol being used.
The IDMS DML Reference for COBOL manual is located at DML Reference for COBOL.
Scroll down on the menu at the left to see the individual sections.
The COBOL=1/2/85 and other parameters are documented at Passing Parameters to the Precompiler.
VS Cobol has been out of support for many years and if Cobol II or LE or something higher is being used, then you would need COBOL=2, which is the default.