GNU/Linux Desktop Survival Guide
by Graham Williams
CTRL-ALT-DEL: The Three Finger Salute
The infamous CTRL-ALT-DEL of the MS/Windows world (to reboot or shutdown your computer) is enabled by default under Debian. It is the following line in the initialisation table that enables this:
# What to do when CTRL-ALT-DEL is pressed. ca:12345:ctrlaltdel:/sbin/shutdown -t1 -a -r now
Thus, the ctrlaltdel action is enabled for runlevels 1, 2, 3, 4, and 5. If you want to disable the CTRL-ALT-DEL salute then simply comment out this line (by inserting a hash).