Set compose key to Shift + AltGr

You can find a list of options in man xkeyboard-config.

Under the section "key to choose the 3rd level" is the one you are after:

lv3:ralt_switch_multikey      Right Alt; Shift+Right Alt as Compose

To enable it, use

setxkbmap -option lv3:ralt_switch_multikey

You should also pass other options you already use to -layout or they will be reverted.

To make it permanent, add it to the comma separated XKBOPTIONS variable in /etc/default/keyboard, e.g.:

XKBMODEL="pc105"
XKBLAYOUT="en"
XKBVARIANT=""
XKBOPTIONS="lv3:ralt_switch_multikey"
BACKSPACE="guess"

That option is defined in /usr/share/X11/xkb/symbols/level3 as

// The right Alt key (while pressed) chooses the third shift level,
// and Compose is mapped to its second level.
partial modifier_keys
xkb_symbols "ralt_switch_multikey" {
  key <RALT> {
    type[Group1]="TWO_LEVEL",
    symbols[Group1] = [ ISO_Level3_Shift, Multi_key ]
  };
  include "level3(modifier_mapping)"
};

In general, if the desired combination weren't available, you could create your own map. E.g., to make the menu key* have that behavior,

==> ~/.config/xkb/symbols/mymap <==

partial alphanumeric_keys modifier_keys
xkb_symbols "mymap" {
    key <MENU> {
        type="TWO_LEVEL",
        symbols[Group1] = [ ISO_Level3_Shift, Multi_key ]
    };
};

Then create this one from setxkbmap -print and append your custom option to xkb_symbols:

==> ~/.config/xkb/main <==

xkb_keymap {
    xkb_keycodes{include "evdev+aliases(qwerty)"};
    xkb_types   {include "complete"};
    xkb_compat  {include "complete"};
    xkb_symbols {include "pc+en+inet(evdev)+mymap(mymap)"};
    xkb_geometry{include "pc(pc105)"};
};

Finally, run

xkbcomp -I"$HOME/.config/xkb" "$HOME/.config/xkb/main" "$DISPLAY"

at every X session start to put load that custom key map.

*xkbcomp "$DISPLAY" - outputs your full key map; useful to find a key name.

posted 6 months ago

CC BY-SA 4.0

6mo ago

Quasímodo‭

691 reputation 14 17 88 32