Custom keyboard layout in Xorg
For most languages there is already a keyboard layout you can use to enter the unique characters for that language. There is no such thing for Lahu so we need a custom xorg keyboard map.
Create your custom key map
You can either define an entire map (tedious and probably unnecessary) or simply inherit all the part you want and then adjust the bits you want changed.
partial default alphanumeric_keys
xkb_symbols "basic" {
// adds the Lahu tone characters to the basic keyboard
include "latin"
name[Group1]= "Lahu";
key <AD11> { [ UF1E7, U02C6, bracketleft, braceleft ] };
key <AD12> { [ U02EC, U02C7, bracketright, braceright ] };
key <BKSL> { [ U02CD, U02C9, backslash, brokenbar ] };
include "level3(ralt_switch_multikey)"
};This rule file is a ‘partial’, including the latin rule file which is essentially the default US keyboard mapping.
The keys are defined for ‘normal’ keypress, shifted etc. They are accessed by the right ‘Alt’ key as indicated.
The codes we are interested in are UF1E7, U02EC, U02CD, U02C6, U02C7 & U02C9. To see the characters they correspond to see the page on Lahu.
Loading your keyboard rules
No need to load this map system wide, use the setxbkmap and xkbcomp commands to load it into the current X session. Stick it in ~/.xinitrc or ~/.Xsession