RE: Symbol's function definition is void

[Drew Adams <drew.adams@oracle.com>]

> few more questions on using this file.
> 1) i m not sure where to store this file. or how to add header2.el
> file path in .emacs.

Add its location to your option `load-path'.

 M-x customize-option load-path RET

or put this in your init file:

 (add-to-list 'load-path "YOUR LOCATION OF HEADER2.EL")

where the string is the directory where header2.el is located.

> 2) i want to add this header in different kind of file like
> .c/.vhd/.v/.cpf/.upf. or in other word i want to use same header
> for any kind of file. what should i add in .emacs.

As the file Commentary says:

;; To have Emacs add a file header whenever you create a new file in
;; some mode, put this in your init file (~/.emacs):
;;
;;   (autoload 'auto-make-header "header2")
;;   (add-hook 'emacs-lisp-mode-hook 'auto-make-header)
;;   (add-hook 'c-mode-common-hook   'auto-make-header)
;;   ...

`c-mode-common-hook' should take care of your .c files.
For the other files, figure out what major mode Emacs uses for each
of them, and then use (add-hook 'THAT_MODE 'auto-make-header).