You can add additional file types to activate Lisp mode with a bit of emacs lisp.

For example, to enable Lisp mode for files with extension ".cl" ".gdl" and ".gendl" you can do (e.g. in your ~/.emacs):

  (add-to-list 'auto-mode-alist '("\\.cl\\'" . lisp-mode))
  (add-to-list 'auto-mode-alist '("\\.gdl\\'" . lisp-mode))
  (add-to-list 'auto-mode-alist '("\\.gendl\\'" . lisp-mode))




On Sat, Feb 8, 2014 at 11:21 AM, Luís Oliveira <luismbo@gmail.com> wrote:
On Sat, Feb 8, 2014 at 2:46 PM, Chintan Pathak <chintan.pathak@gmail.com> wrote:
> When I write a program and compile using C-c C-c or C-c C-k, it says these
> are undefined.

Where did you write your program? Was lisp-mode activated? If your
file has a ".lisp" extension, Emacs should activate lisp-mode
automatically.

HTH,

--
Luís Oliveira
http://kerno.org/~luis/




--
My Best,

Dave Cooper