Eli,

I can implement the functions for Windows and OSX.  I believe all Unices
have implemented the XDG Base Directory Specification.

But we do have a problem: once this is implemented for all operating
systems, XDG will become a meaningless package name and prefix.  Maybe we
should not have a prefix at all and find sensible names not used by Emacs
at the moment.

I propose that xdg-config-dir becomes instead user-emacs-config-directory
and gets to be initialised according to the operating system's best
practices.  Defaulting to ~/.emacs.d/config.  user-emacs-cache-directory
defaults to ~/.emacs.d/cache and user-emacs-data-directory to
~/.emacs.d/data.  The defaults would only be used iff the operating system
determination functions return nil.

user-emacs-directory could either be an alias of user-emacs-data-directory
or default to it.

locate-user-emacs-<domain>-file would then make sense, and no names should
be changed.  I think I should make these functions with the same interface
of locate-user-emacs-file, and give it analog behaviour.

In my opinion, the chain of user-init-file should be (in order of
precedence):

  1. (locate-user-emacs-config-file "init.el")
  2. (locate-user-emacs-file "init.el")
  3. ~/.emacs.d/init.el
  4. ~/.emacs (and the rest of the present order, like terminal specific
files).

Would that seem sensible to you?

  Francisco Colaço