On Sun, 24 Aug 2008 09:24:06 -0700, jp2msft
<jp*****@discussions.microsoft.comwrote:
Imagine having Machines out on the floor and an application you wrote
keeps
someone from accidentally getting killed. [...]
All due respect, if you've got a machine that keeps someone from getting
killed, Windows isn't the right operating system. Neither is Linux, Mac
OS, or Unix for that matter.
For less critical applications, but where it's still important to keep
users from meddling, there are certain techniques that apply. But they
generally involve not giving the user access to the application (the
critical parts run as a service, for example) or to the input device (not
providing a keyboard, for example). The Ctrl-Alt-Del combination is
particular difficult-to-impossible to block in software, because it has a
very special, high-priority-override meaning in Windows. If Windows
provided an approved mechanism for disabling or otherwise diverting that
key combination, it could cause serious security issues when that
mechanism was used by malicious software.
Some of the other combinations might be interceptable by keyboard hooks or
the like, but even there one should tread cautiously. It's practically
never the correct solution for one application to hijack the operating
system's normal UI behavior.
Pete