Re: Handling Files in a Subproceedure

Mike wrote:

I might be calling this in a loop; for sure every displayed record. I
have the activation group as *CALLER. So all I have to do is check to
see if the file is open, and if it is to just continue processing?

That'll work.

Though, I'd probably create a procedure that opens all of the files you need, and then I'd simply call that procedure. The procedure can use %open() or a global indicator to verify that it doesn't do the work twice. The only reason I do that is to keep all the file open logic from cluttering up the main subprocedure. (Plus, the code tends to be repeated in every routine in the srvpgm).

I also like to code a "closefiles" subprocedure that does the opposite (closes all files) and turns off the global indicator (if you use one). This prevents a warning message from the compiler (it complains that the files are USROPN but you never close them unless it finds a close statement.)

You can even register your "closefiles" routine to be called automatically when the activation group ends. That's useful if you have any custom code you want to run when it shuts down (such as deleting a temp file, data queue, user space, override, etc.)

If you're looking for the "simplest" alternative, then you can simply omit the "USROPN" from your F-spec. In that situation, RPG will automatically open the file(s) the first time anything in the module is called. They'll still be closed automatically when the activation group ends, of course. With that logic, you don't need to code any open or close... Personally I like it to be explicit, but many people think I'm crazy.