Main functions provide the basic structure of a VisualAge Generator program. You can define up to 254 main functions. When the program runs, control usually transfers from one main function to the next.
To insert a main function into your the structure diagram of your sample program:
Figure 47. Insert Main Function window
The name of the main function is displayed in the structure diagram in the Program Editor. The question mark beside it indicates that the function has not yet been defined.