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Cleaning up after Modules

In multiple-program format, each module program not only gets automatic initialization, it also has the operating system cleaning up after it when it exits. In monoprogram format, this benefit is also lost. It is therefore important for the menu section of the attract to close certain things down after each module returns.

• kfClose. Few, if any, dialogue modules are careful to close their keyed files before they exit. PDisplay, however, allows only one keyed file to be open at once, so kfClose has to be called before the next kfOpen.
• Reclaiming the heap. This is a very delicate matter, and whether it should be done from the Attract menu at all depends on the individual dialogue. Some dialogues will permit the heap to be marked before a module is called, and released afterward. With others, the use of the heap is too intricate, and requires at least some of the modules themselves to do all cleaning of the heap.