Runs an iteration of the message loop.
int IupLoopStep(void); [in C] IupLoopStep() -> ret: number [in IupLua3] iup.LoopStep() -> ret: number [in IupLua5]
This function returns IUP_CLOSE or IUP_DEFAULT.
This function is useful for allowing a second message loop to be managed by the application itself. This means that messages can be intercepted and callbacks can be processed inside an application loop.
An example of how to use this function is a counter that can be stopped by the user. For such, the user has to interact with the system, which is possible by calling the function periodically.
This way, this function also replaces some old mechanisms implemented using the Idle callback.
Note that this function does not replace IupMainLoop.