With the use of free-format (aka /Free) RPG logic becoming more and more popular, many shops are beginning to utilize prototypes for their program calls because the CALL operation code is one of those that doesn't work in free-form. This is a movement to which I say, "It's about time!" For far too long, many shops have used prototypes only with subprocedures. Even with this upswing in the use of prototypes, however, I've found that many programmers are still not taking advantage of all that prototypes have to offer.
This is the second of two articles discussing the basics of working with API-related data.
By Bruce Vining
When we left off in Part I, we were just calling the Retrieve Call Stack API, QWVRCSTK, for the first time. The program being discussed is repeated below. If you would like to review the API documentation, it can be found here.