I've raised a bug (bug#22392) about Emacs on OS X not setting the locale
and character encodings when launched from the GUI (finder, spotlight,
etc.). As far as I can tell it's because Emacs looks at LC_ALL, LC_TYPE
and LANG for the locale information, but it's not set when launched from
the GUI. It IS set in terminal.app, so if you launch from there it all
looks good.

Apparently the Windows version has the same problem and sorts it by
setting LANG from a function called early in in main in emacs.c.

I've written a patch that copies this method. It calls the NextStep
function for getting the locale and then sets LANG if it's not already
set. I'm not sure that's it's the best way of doing it. I had to create
a new Objective C file and header to include in emacs.c.

There was also a question raised about what the correct character
encodings are for OS X. On my machine it sets LANG to en_GB and most of
the character encodings to iso-latin-1-unix, which looks OK to me, but
it was suggested that they should be UTF-8.

Does anyone know what the correct encodings are on OS X?