<< I don't see much reason to study one more language just to solve this problem.>>
On the contrary you've traded approaches "just" to solve the problem and avoid additional debugging. That said, stating to use RPG for DB I/O on the i is like bread with butter or chocolate with peanut butter, they go hand in hand. It would also encapsulate the record i/o and lead to faster debugging. Your problem was approached from a record i/o perspective and RPG is a reasonable alternative on the i. No one said you "had" to learn a new language. And if you really need to manage message passing between programs and program "X" is waiting for programs "Y" messages then either some form of IPC communications is in order, such as queues, TCP, pipes, etc. User spaces are really ill-suited to "that" type of solution/problem. But if program "X" is waiting on a complete bunch of records, then just use stream files, it's a heck of a lot simpler, albeit much more powerful on the i to use from C than user spaces. It's not even a question.
And I won't suggest using SQL instead because I don't want to be accused of suggesting learning yet another language to solve the problem, so I did not say that.
After all you put out this thread and asked for help. Someone else might benefit from it in the future even if you think you've solved the problem, which none of your threads indicated that was the case(solved) by the time I read them today.
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