Markus Kuhn did a great deal of work for unicode for unix, see the rest of the same folder, https://www.cl.cam.ac.uk/~mgk25/ucs/

such as examples/UTF-8-demo.txt a beautiful demo file for testing terminal emulators

or the wcwidth.c file I discovered was the origin of the same c function found in all OS's, i forked & maintain in python form as the public "wcwidth" module,

anyway just wanted to point out the treasure trove of the parent folder!