bug#14110: 24.3.50; Add command to open files outside of Emacs (use xdg-open, open etc)

[Jambunathan K <kjambunathan@gmail.com>]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

>> Add support for opening files outside of Emacs (use xdg-open, open etc).
>> This is something that I sorely missed or continue to miss.
>
> For those people who find xdg-open not customizable enough, I think
> open-file deserves an alist associating different commands to different
> file kinds.
> I guess in this sense I agree with Leo, that it should probably use
> dired-guess-shell or something like that.

I have looked at the variable that Leo mentions, prior to preparting the
patch. (Hint: The COMMAND is a sexp.  It can theoretically be a `cond'
or a `case' statement.) I want the new customization to be simple and
not over-engineered and in a way that is welcoming of the new user while
giving power to the more experienced.

To allow for a possibility that a generic open command may not be
available, I have arranged for a `read-shell-command' and remembering
the command name so entered in `dired-shell-command-history'.

Furthermore, the open command need not be xdg-open, it could be
gnome-open or kde-open.  (If you look xdg-open you will see that it
internally checks for desktop open and calls the native open method.)

    (defun open-file (filename)
      "Open FILENAME (presumably) outside of Emacs.
    Use shell command from `open-file-command' to open the file."
      (interactive "fOpen file:")
      (require 'dired-aux)
      (let* ((default-directory (file-name-directory filename))
             (filename (file-name-nondirectory filename))
|             (command (or (eval (cadr (assq system-type open-file-command)))
|                          (read-shell-command (format "Open %s with: " filename) nil 
|                                              'dired-shell-command-history))))
        (when (and command (string-match "\\S-" command))
          (dired-run-shell-command (dired-shell-stuff-it command (list filename) t)))))



>         Stefan