Re: setenv -> locale-coding-system cannot handle ASCII?!

[Richard Stallman]

      So, in a
    multibyte sesstion "(format "%s" 1)" yields a multibyte
    string.  :-(

If format sees that all the characters are one-byte, it could make
this a unibyte string.

    By the way, I also really really hate this unibyte/mulitbyte
    problem.  Sometimes I think I should have opposed to the
    introduction of such a concept more strongly.

It is possible that nowadays we do not need unibyte buffers and
strings any more.  Perhaps now the only kind of benefit that
a unibyte buffer provides is a speed advantage for Tar mode
and similar programs.  It would be interesting to find out if
tar mode works right with multibyte buffers, and if so, how
much of a slowdown that entails when reading a large tar file.

But there may be another benefit.  Using unibyte buffers would also
mean that the user will never be asked what encoding to use.  And some
users may really dislike being asked!

We could imagine replacing the current unibyte mode of operation with
one in which visiting files always uses no-conversion but makes
multibyte buffers, and then make sure that works just like using
unibyte buffers does now.  If we get that to work well, then we
could use that instead of unibyte mode.  Then we could reserve
unibyte buffers for things like tar-mode, or use eliminate them
entirely if tar-mode runs fast enough with multibyte buffers.