Your (a) case was what I was looking for (as I still want to be able to split other windows vertically) and setting split-width-threshold to nil worked great.  Thanks.

Andy

On Tue, Aug 11, 2009 at 1:42 PM, Tassilo Horn <tassilo@member.fsf.org> wrote:
Andrew Goodnough <agoodno@gmail.com> writes:

Hi Andrew,

> I'd like the Buffer List to always appear as a horizontal window at
> the bottom.  But when I have emacs maximized and show the Buffer List,
> it appears in a new window, split vertically on the right side.  I
> think emacs is trying to be smart about where I've got the most screen
> real estate at the moment but I wish it would always go on the bottom.
> Is there a variable to set this by chance?

Is that (a) special for the buffer list, or (b) do you want emacs never
to split vertically?

In case (b), add

   (setq split-width-threshold nil)

to your ~/.emacs.  In case (b), you can use an advice around
buffer-list.

   (defadvice list-buffers (around forbid-horizontal-split activate)
     (let ((split-width-threshold nil))
       ad-do-it))

Bye,
Tassilo