Global callback for an entry point. Used when main is not possible, such as in iOS and Android systems.
It is called only once, when the main loop is processed, but after IupOpen. For regular systems is called right before the actual event loop is started.
void function(void); [in C]
It can only be set using IupSetFunction(name, func).
To modify this action use the iup.SetGlobalCallback(name, func) function.
IupSetFunction, EXIT_CB, IupMainLoopLevel