Keyboard Interception in OSX

Question

I am trying to write an application that prevents the spread of some key signals outside the OS in OSX. To clarify, I want to make it almost seem to the user that the key that they click on the keyboard is broken. Thus, the linked letter will not be displayed in the text field, the key does not activate the function in another application, etc. Any ideas? Thanks in advance.

Answer 1

You probably want to take a peek at Quartz Event Taps . Please note that your process must be run with root privileges in order to intercept events at the system level.

See also Quartz OSX Event Separators: Event Types and Event Editing Methods