For Hitch and Brock:
From Wikipedia, since the goddamn thing lags so much. <http://www.wikipedia.org
/wiki/SysRq>

SysRq

From Wikipedia, the free encyclopedia.

There is a key labeled SysRq on keyboards for PCs that no longer has a
standard use. The BIOS keyboard routines simply ignore it; therefore so do the
DOS input routines as well as the keyboard routines in libraries supplied with
high-level languages.

The key is not totally inactive, however. When it is pressed, nothing is
stored in the keyboard buffer, but a BIOS function is called. The default
handler of that function does nothing and simply returns. Programs can use
SysRq simply by creating an interrupt handler to replace the default stub, but
most programs have no need for that functionality. When software that has the
potential to completely lock up the system is run, a BIOS interrupt is the
only input that could be generated; the SysRq BIOS interrupt handler can then
be written as a form of "panic button" to gracefully terminate the program or
reboot the system.

In Linux systems, provided the kernel has been compiled with the correct
option, the key can be used to perform a variety of functions in an emergency,
such as syncing disks, killing processes and powering off the computer.

++Hablo


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++Hablo