QUI Interrupt Button

When you select the Interrupt button, Prolog execution is suspended. A selection dialogue is then displayed from which you will determine the next action,

Execution is resumed. Execution will continue as if Prolog had never been interrupted.
Execution is immediately aborted (see ref-iex-int for more information about abort).
Execution is continued but traps to the debug window when the next debug port is reached.
Execution is halted and all QUI windows are closed.

Typing ^C in the main window will also display the interrupt dialogue (see qui-mai-top-key for more information).