emacs view open buffers as a tree

Is there any emacs mode that will give me a list of my open buffers as a tree? By tree, I mean a directory tree, where buffers are grouped together if they are visiting files that reside in the same directory.

In vanilla emacs, or even icicles mode, the views I have seen of the buffer list have all been flat. A tree view would help me m开发者_StackOverflowore quickly make sense of which buffers are open and the relation between them.

Although it doesn't exactly provide a tree view, I think you'd be happy with the grouping features in ibuffer-mode which is an alternative to the default buffer list mode. It's built into Emacs >= 22.

(global-set-key (kbd "C-x C-b") 'ibuffer)

There's an Emacswiki page, but the best overview of the grouping features is probably this blog article.

Edit: I just hacked together some code to group my own ibuffer list by the vc parent directory of each buffer. It also allows ibuffer to display the version control status of each listed file. Perhaps you'll find that helpful.

Possibly a bit heavyweight for what you want, but have you looked at Project Buffer Mode?

http://www.emacswiki.org/emacs/BufferMenuPlus. Sort by dir+file name.