Write information to a display?

spamtrap_at_crayne.org
Date: 02/25/05 

Date: Fri, 25 Feb 2005 02:47:14 +0000 (UTC)

Hello.

This may be the wrong group to post to, but I assume someone here would
know a good anser. Any recommendations for a different group would be
appreciated as well.

I am writing a covert channel for a class, where you pass information
based on an encoding scheme for a shared resource. As an example, if a
file is locked by one program, it is a 1, and if it is not locked, it
is a 0. One program either locks or does not lock the file every
second, and a 2nd program reads if the file is locked or unlocked every
second.

Anyway, I was wondering if there was any way to write some sort of
setting or any piece of information to a computer display, so that if
using a KVM switch (keyboard, video, mouse), one computer could write a
setting, and then when the KVM is switched to the second computer, the
other it could read the setting.

I looked into doing this with the caps lock on a keyboard, but it turns
out that the keyboard doesn't store the state of the caps lock, the
computer does.

Any advice would be great.

Thanks a lot!

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