> Being pedantic about forcing some encoding onto things that don't
> have an encoding won't really work out in practice. Dealing with
> file names, OS environments, pipes and sockets is dirty work, so
> I think we should go with the 80-20 approach in making 80% easy
> and 20% harder, but still possible.

Unix applications can always use the byte-oriented file name APIs
if they need to. Then you are back to the state that things have
in Python 2. No need to have a user-tunable file system encoding
there.

However, I completely fail to see the advantage that the
PYTHONFSENCODING variable has over the LANG variable. If it's
possible to set PTHONFSENCODING in some application, it surely
is also possible to set LANG (or LC_CTYPE), no? Setting the
latter also gives you the advantage that environment variables
and command line arguments use the same encoding as file names.