Problem figuring out the encoding for filenames with special characters

Question

I'm not sure if this is the right forum, but this does seem like an OS issue.
I brought in a lot of mp3 and m3u files from a Windows machine to my new Mac. Some of the mp3 files have accented characters in their names, and these names appear in the m3u files. But if I add the m3u file to iTunes, it fails to recognize these names and so I lose all the mp3's with special characters in their names.
I tried to fix this by grabbing the files name in Python, but that didn't work either!
Here's an example: the file's name is "Voilà l'été.mp3"
The m3u files says "Voil\xe0 l'\xe9t\xe9.mp3" -- this doesn't work.
From os.listdir(), I get Voila\xcc\x80 l'e\xcc\x81te\xcc\x81.mp3", but sticking it in an m3u files doesn't work either. (Note that here the characters are encoded as unaccented letter + two byte code for the accent).
When I try these strings from python, e.g. doing os.stat(), they both work; but iTunes doesn't understand any of them!
I'd appreciate any hints on how to enter these names in the m3u file so that iTunes can read it. Thanks!

Answer 1

I know nothing about "m3u" files and how iTunes interprets the file names in them, but if it is not a relative/absolute path problem, then how about just putting the raw file names (not the ones with backslash escape) in m3u file? For example, just put
Voilà l'été.mp3
in m3u?
As for Unicode encoding, HFS+ file system uses the "decomposed form" for accented characters. This means, as you write, à is hex "61 cc 80" in UTF-8, i.e., "a + COMBINING GRAVE ACCENT". The pre-composed form is hex "c3 a0". But my experience is that in most cases both pre-composed and decomosed forms work at the user level (not at the lowest file system level).