Re: Use .emacs.d in savehist.el

["Richard M. Stallman" <rms@gnu.org>]

    If normal libraries follow init-file-user, you could have a situation
    where a user tries to write customization files into the home
    directory of another user.  This doesn't make much sense, but I don't
    understand when it makes sense to set init-file-user in the first
    place.

If the customized values that Emacs read _came from_ another user's
init file, the only place to store them back is into that user's init
file.

Ordinarily you won't be able to write that file.  Instead you will get
a clear error message saying so.  That seems correct to me.

Meanwhile, in at least one case you WILL be able to write that file.
Namely, when you are root and you told Emacs to use your own personal
init file.  (In particular, this is what happens when you run emacs
under su.)

So we ought to make this work.