Define the DosExit Function used in the OS/2
DosExit(action, resultCode)
DosExit function is to be called when a thread or process is finished executing. If EXIT_THREAD is passed as an action code (action), the current thread ends. If EXIT_PROCESS is passed as an action code, all threads in the process end. The resultCode is used to pass exit state information back to any thread waiting with a DosWaitChild for this process to complete.