When using the debugger, you can cause execution of the program to pause by selecting Debug|
[0]Break. To terminate execution of the program, select Debug|
[0]Kill, or try one of the following if you're on a Mac.
Macintosh. To stop a program you are debugging (perhaps because it is in an infinite loop), type control-command-/. This should return control to the debugger. The program window will show the location in the program where execution is paused, and you can use the debugger to appraise the situation.
If control-command-/ doesn't work, try forcing termination by pressing Option-Command-Esc. If you want to continue debugging, you will have to start from the beginning.
Occasionally a problem will cause the machine to lock up or freeze. If neither of the above steps salvages the situation, you will have to restart the machine. Don't do this unless you have to - all unsaved work in open applications will be lost.