This problem is strange, but it's my formal task. I am not main project designer. I have limited "free-hand". Project's aim is to make some runtime library with own internal data and additional ENV manipulation functionality. I know that some future functions in this library will launch some cobol programs that require uppercase ENV, that's all. Now I'm at the beginning and want to deside how to make this better for the future tasks.

I thought about this like Anno wrote. Thanks him for advise not tie magical vars, I didnt knew it. I may change code. So only two or even "one and a half" ways remain.