The SIGNAL() function raises a cross-process application signal.
The SIGNAL() function provides a simple way to notify another QM process of a condition such as a request for a phantom to terminate. It returns True if the process identified by user.no is logged in.
OK = SIGNAL(SERVER.USER)
This statement raises a cross-process application signal in the QM process with the user number in SERVER.USER.
The signalled process detects this signal using SYSTEM(1062) which will also clear it. For example, a phantom server process might have a main loop as below: