Preventing application from receiving a keystroke

I want to create an application in which, when it starts executing, the user can not perform keystrokes and the application cannot receive any events fro开发者_StackOverflow中文版m keyboard, such as command+Q,command+shift+3, etc. I just want to disable some key combination so that i can make my application secure

You can create a carbon evemt for this hot key (3+shift+cmd) http://cocoasamurai.blogspot.com/2009/03/global-keyboard-shortcuts-with-carbon.html