The original C_AppControl API should likely be the C_System one. This isn't a difficult task, but if a network connection exists the logic would be slightly different:
In offline mode, simply exit the app immediately
In online mode, send a logout request to the world server
The server should then respond with a timer
Start counting down and exit the app when it finishes
Also display an Exit button that will quit immediately (before the logout is complete)
The original
C_AppControlAPI should likely be theC_Systemone. This isn't a difficult task, but if a network connection exists the logic would be slightly different: