I need to implement keyboard layouts for several african languages, some with complex tonal marks: acute, grave, grave with dot below, acute with dot below (these are the ones i know now, but there may be others). many of these characters do not have unicode code points of their own but they can be represented using combining diacritical marks: ie S with acute and dot below is S + U+0300 U+0323 - this is what i understand but i may be wrong so please correct me.
My question is how do you implement such solution on linux? looking at the Compose file for en_US.utf8 it seems composing sequence characters can only be mapped to another unicode code point: eg. <Multi_Key> <U10001100> <U10001100> : "'' " U1101
How do you compose keys with multi_key or dead keys that emit more than one code point?
Can this be implemented in the xkb keyboard layout/variant file? if so, how?