* How do I use the magic SysRQ key? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ On x86 - You press the key combo 'ALT-SysRQ-<command key>'. Note - Some (older?) may not have a key labeled 'SysRQ'. The 'SysRQ' key is also known as the 'Print Screen' key.
On SPARC - You press 'ALT-STOP-<command key>', I believe.
On PowerPC - You press 'ALT-Print Screen-<command key>'.
On other - If you know of the key combos for other architectures, please let me know so I can add them to this section.
* What are the 'command' keys? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 'r' - Turns off keyboard raw mode and sets it to XLATE.
'k' - Kills all programs on the current virtual console.
'b' - Will immediately reboot the system without syncing or unmounting your disks.
'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.)
* Okay, so what can I use them for?
