Ubuntu – Restoring the original keyboard mapping without logging on

Changing the mapping of the control key is a two step process. The first part is to get the right information for the keycode and keysym. The second part is to make sure the modifier mapping is right.

It sounds like you've got the correct keycode already so try this instead. Create a file myxmodmap with the following

clear control
keycode 97 = Control_R
add control = Control_R Control_L

Now process the file with xmodmap

[~]$ xmodmap myxmodmap

If you want those xmodmap expressions to be processed each time you log in change the file name to ~/.Xmodmap

You should be able to simply use Keyboard Layout >> Options >> Ctrl key position >> Right Alt as Right Ctrl, but this doesn't work. This has already been filed against Debian as Bug#663218

1. Start fresh by deleting ~/.Xmodmap.

2. Note that you do not need to clear Control and Mod1. This makes it easier to change only what you want. Your ~/.Xmodmap shoud be:

   !Swap right control and right alt
   remove Control = Control_R
   remove Mod1 = Alt_R
   keycode 105 = Alt_R
   keycode 108 = Control_R
   add Control = Control_R
   add Mod1 = Alt_R