Linux/X11 Keyboard interceptor


for some twisted reason, i need to write a program that locks any input from keyboard/mouse for other than my application.
I already tried, with limited success, with SDL WM_GrabInput, but that does not grab key combinations like CTRL+ALT+BACKSPACE or CTRL+ALT+F2.

What i need is advice, and possibly C (im programming in FPC for this) code to accomplish a total lockout from the keyboard, in order to prevent X shutdown, or console switching.
I dont expect answers or comments like "use XDM" or "disable the TTYs and run in X runlevel", since that's not what im looking for (actually might be the worst case scenario if there's no other solution to my problem".

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astrandConnect With a Mentor Commented:
> DontZap does not prevent console switching.0

Ah, sorry. DontVTSwitch is what you want in this case.

As for listen to all events, try the program
Get the source of the "xev" utility.

It's a small X11 utility that allows you to grab any X11 events (including key presses/releases).
It's a very old X11 stuff which is a perfect example of what you are trying to achieve. It uses native X11 calls.
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To prevent the Xserver from ending / switching to VTs on CTRL+ALT+BACKSPACE / CTRL+ALT+F2, you need to change you XF86Config. Activate options DontZoom and DontZap.
KiCkAuthor Commented:
DontZap does not prevent console switching.
DontZoom prevents the user from switching screen resolution, which i actually need :)

As for xev, that captures the events from within the window, not from all windows.
I know the xev does not get all events, but it's a good example of what can be done.
Based on that, you can do whatever you want.
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