See /usr/src/linux-*/Documentation/sysrq.txt for information about why
and how to use sysreq.

To force a crash:

	Turn on sysrq:
		sysctl -w kernel.sysrq=1

	Trigger the crash
		echo c > /proc/sysrq-trigger

/proc/sysrq-trigger is typically a 2.6 thing, but nice to have when you
aren't on the console.  It's apparently also been backported to RHEL 3
kernels.

What are the 'command' keys?
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
'r' - Turns off keyboard raw mode and sets it to XLATE.

'k' - Secure Access Key (SAK) Kills all programs on the current virtual console. NOTE: See important comments below in SAK section.

'b' - Will immediately reboot the system without syncing or unmounting your disks.

'c' - Intentionally crash the system without syncing or unmounting your disks. This is most useful if the NETDUMP client package has been installed.

'o' - Will shut your system off (if configured and supported).

's' - Will attempt to sync all mounted filesystems.

'u' - Will attempt to remount all mounted filesystems read-only.

'p' - Will dump the current registers and flags to your console.

't' - Will dump a list of current tasks and their information to your console.

'm' - Will dump current memory info to your console.

'0'-'9' - Sets the console log level, controlling which kernel messages will be printed to your console. ('0', for example would make it so that only emergency messages like PANICs or OOPSes would make it to your console.)

'e' - Send a SIGTERM to all processes, except for init.

'i' - Send a SIGKILL to all processes, except for init.

'l' - Send a SIGKILL to all processes, INCLUDING init. (Your system will be non-functional after this.)

'h' - Will display help ( actually any other key than those listed