Hi. This is my first post here. I looked thru a some posts on this topic and couldn't seem to find what I was looking for. I just installed Ubuntu Release 24.04.2 LTS (Noble Numbat) 64-bit with MATE 1.26.2.
I want to assign the unicode NOT symbol (U+00AC) to a key on the US keyboard. Since there's nothing I want to nuke I'd like to use a CTRL-. I have been playing with xmodmap to change the key bindings. This works with SHIFT-, but CTRLs seem to get eaten somewhere and function as dead keys. It appears that only a few standard controls are active, such as CTRL-c, CTRL-d, etc.
I have been playing with the 6/caret(^) key. Assigning "notsign" to the shifted position of this key works, but of course overlays the caret. Assigning it to the control position leaves a dead key. Xev shows no character value being generated.
xmodmap -verbose -e "keycode 15 = 6 asciicircum notsign asciicircum"