For unix it's `user-emacs-directory` but on Windows it's trickier:
http://emacswiki.org/emacs/DotEmacsDotD

I can't vouch that's an up-to-date article though.

-Steven


On Wed, Apr 3, 2013 at 7:01 PM, Joe Riel <joer@san.rr.com> wrote:

> Is there way that specifies the path to the .emacs.d
> directory that works on Linux, Windows, and Mac?
> Currently I use
>
>   (format "%s/.emacs.d" (getenv "HOME"))
>
> However, I doubt that is necessarily correct on Windows.
>
>
> --
> Joe Riel
>
>
>