SWI-Prolog -- at

Availability:built-in

at_halt(:Goal)

Register Goal to be run from PL_cleanup(), which is called when the system halts. The hooks are run in the reverse order they were registered (FIFO). Success or failure executing a hook is ignored. If the hook raises an exception this is printed using print_message/2. An attempt to call halt/[0,1] from a hook is ignored. Hooks may call cancel_halt/1, causing halt/0 and PL_halt(0) to print a message indicating that halting the system has been cancelled.