MagicSysRq keys for assistance with Ubuntu troubles

[PmDematagoda]

I have been looking into the problem, and I do think it has something to do with the X-Server, or with the evdev driver. The reason I suspect the evdev driver is because it catches all events and handles them, so the events for the SysRq keys may not be picked up by the kernel due to that and hence, no action. The X-Server may also have a hand in this, but I will need to spend some time to get the kbd and mouse drivers working before I can confirm that suspicion.

Just an FYI, SysRq keys don't work in Fedora 9 as well, which has X 1.5.2 and the evdev driver. Of course, that may be due to the keys being disabled in the kernel config, but compiling a kernel of my own with the keys turned on hasn't helped.

[Reilithion]

Since upgrading to Jaunty, I'm able to use Magic SysRq. I believe the issue may have been fixed. I should note that the default screenshot keyboard combination in Gnome is Alt-PrintScreen which interferes with Magic SysRq sometimes, and I noticed I can only send at least some of the commands (such as 'b') with the left Alt key on my keyboard.

[bobpaul]

I noticed I can only send at least some of the commands (such as 'b') with the left Alt key on my keyboard.

That's interesting. Generally if it only works with one Alt key, it works with the right Alt key (Alt Gr). Thanks for the heads up on the fix. It does indeed appear to be working in Jaunty.

[-_- Joseph -_-]

My ubuntu freezes when im in the middle of a game. so this was a useful thread for me

keep up the good work

,Joseph

[kevinguillorytraining]

I frequent forgot my key combination. But after finding your tutorial I'll no more worried

[maatuntu]

Thank you for this tutorial. I am new to Linux, but have to reinstall ubuntu several times. I can only assume this is to unsafe rebooting and shutting down. Thanks for making this available, I am using years after it was first posted

[SaintDanBert]

What's a guy to do when he's on a laptop and must use a "Function" key to access system keys such as "Print Screen" and such?
...

My Thinkpad also has this keyboard configuration: Fn activates alternate features of the keyboard shown as "blue text" on the key cap. Here is a dance that I found works.

1. press and hold ALT (keep holding)
2. press and hold Fn
3. press and release PrtSc(SysRq)
   
   I get a "SysRq Help" string splashed across the console
4. press and release whichever command character
   
   I get a one line announcement "SysRq command" announcing whatever the command letter does. The details go into /var/log/syslog
5. release ALT when all command characters typed

ASIDE: I don't know how to capture text during a console session or I would include an example here.

The above only works from a console CTRL+ALT+Fx while running X11 or without X11 entirely. Fx means "F1" ... "F6" not the Fn key.

If X11 is running, any use of PrtSc(SysRq) activates the screen capture utility so you cannot even use the Raw command key to grab control. Even if I had an xterm or similar open, I kept getting the screen capture dialog.

This writer really, REALLY, REALLY needs a work-around so that he can use magic keys while X11 runs.

Thanks,
~~~ 0;-Dan

[bobpaul]

If X11 is running, any use of PrtSc(SysRq) activates the screen capture utility so you cannot even use the Raw command key to grab control. Even if I had an xterm or similar open, I kept getting the screen capture dialog.

Do you have an Alt Gr key? Use that instead of Alt. If you don't have a key labeled Alt Gr, your right Alt key is generally Alt Gr (even when not labeled). Use that instead of left Alt and you shouldn't get a print screen dialog.

Otherwise you can remap the key Gnome uses for print in System->Administration->Keyboard Shortcuts. Change both "Take a screen shot" and "Take a screen shot of current window" to other keybindings and your problem should be solved.

[soumoks]

sorry for being a noob but which is the sysrq key?

[bobpaul]

sorry for being a noob but which is the sysrq key?

It's the key on your keyboard that has "SysRq" or "SysReq" written on it. On a desktop PC, it's commonly the same as "Print Screen" or "PrtScn". On a Laptop it's often on it's own key and requires you press the Fn key to use it.