On Wed, Jun 09, 2010 at 08:48:01AM +0800, hkm wrote:
> Does anyone know how to start emacs in a given mode?
> 
> Actually I use matlab-shell in emacs. Everytime I have to start
> emacs first, and then I can enter matlab-shell mode.

What do you mean *every time*?  Why not leave Emacs running and open
files or your shell from within Emacs?

> Is there a way to make emacs enter matlab-shell mode automatically
> when type some command in the terminal?

M-x customize-variable RET major-mode RET

Then put in your favorite major-mode (mine is org-mode) and save the
setting.

You can accomplish the same with

(setq-default major-mode 'my-favorite-major-mode)[1]

Joel

Footnotes: 
[1]  Evaluate this: (info "(emacs) Choosing Modes")

-- 
Joel J. Adamson
Servedio Lab
University of North Carolina at Chapel Hill

FSF Member #8164
http://www.unc.edu/~adamsonj