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I have a computer with Fedora 16 and KDE. It's connected through a KVM switch to a monitor with another computer, and the switch uses Scroll Lock + Scroll Lock to switch between the computers.

The problem is that for some reason the Scroll Lock button doesn't work on Fedora/KDE. Num Lock and Caps Lock work. The command xset q says that it's off, and xset led named "Scroll Lock" does turn it on, but I can't "double-click".

How can I check why the button isn't working and resolve the problem? I have looked everywhere and haven't found anyone with this specific problem.

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1 Answer 1

I once was pulling my hair out for a while trying to figure this out. Apparently, Scroll Lock isn't by default detected by X so you have to make it recognize and detect that key, if you are in that boat.

  1. Open a terminal.

  2. Run xmodmap -pm to check which mod keys are available. Usually there is at least one. In my case mod3 was available. So I would run the following (your available mod key may differ, so use that number when you run the next command).

  3. Run xmodmap -e 'add mod3 = Scroll_Lock' and the Scroll Lock key should begin working in X.

  4. To make this permanent, you can add a startup item in your window manager/environment or use another method like putting that in your .xinitrc file or create a file in xinitrc.d to do that (if these still work for your distribution of Linux, or use another method if they don't).

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Thanks, I upvoted your comment because it seems like the correct solution, even though the setup I'm using now is different and the question is no longer relevant for me specifically. Hopefully someone else finds this useful. –  Ynhockey Nov 3 '14 at 10:58
Dude! You are the man. Needed this to make my cm devastator keyboard backlight work on Fedora 21. –  penner Dec 21 '14 at 2:40

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