Re: Gnuserv vs Emacsserver

[Chetan]

Chetan <Chetan.xspam@xspam.sbcglobal.net> writes:

...

> I have wondered about swithing to emacsserver for some time. I have
> been using gnuclient for a long time (on W32). Changing over to
> emacsserver became a possibility with emacs 22, but I haven't yet done
> it.
>
> For my style of working, I find there are irritations in switching
> over. I wonder if anybody has any solution.
>
> 1. My version of gnuclient starts emacs (if it can find it) if it
> cannot connect to a running instance. I could, of course, make sure it
> is running before I use it.
>
> 2. Irrespective of whether I am running emacs 21 or 22, it can still
> connect.
>
> 3. The biggest irritant is that if I start another instance of emacs,
> either by mistake or because I want to do something in a console
> window, it clobbers my previous instance. With gnuserve, it fails with
> a dialog box, which is also irritating, but it works the way I want
> it. Ideally I would not like to keep changing the commandline, but I
> don't see how I would do it even with that.
>
> 4. I need to change too many places in the system registry where it
> invokes gnuclient. I can perhaps do that if I can handle the others.
>
> Chetan

After looking at the suggestions, I have tried to work on my most
irritant point 3.

Here is a package that does what I want.

Now the next is to try item 4. Looks like creating an executable that
handles the same arguments but uses emacsserver is the simplest.
I will try to do that for me.

Chetan

;; server-x.el -- provide functions for starting emacsserver differently
;; Copyright 2008 by Chetan Pandya <pandyacus@yahoo.com>
;;
;; This file is NOT (yet) part of GNU Emacs.
;;
;; This program is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 3, or (at your option)
;; any later version.
;;
;; This program is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.
;;
;; You should have received a copy of the GNU General Public License
;; along with this program; if not, you can either send email to this
;; program's maintainer or write to: The Free Software Foundation,
;; Inc.; 59 Temple Place, Suite 330; Boston, MA 02111-1307, USA.
;;
;;; Commentary:
;;
;; This emacs script provides functions starting emacsserver with
;; additional information than server-start.
;;
;; Installation:
;;
;; Simplest way is to `load' or `require' the file.
;; Customize the startup action, if desired.
;;

;;; Code:

;; User configurable variables:

(if (< emacs-major-version 22)
    (error "Not supported on emacs version before 22.0"))

(defcustom server-startup 'check
  "Deal with existing files at startup"
  :type '(choice
          (const :tag "Ignore - delete file. Default in absence of server-x" 
nil)
          (const :tag "Search - set server name" search)
          (const :tag "Abort" check))
  :group 'server)

(defvar server-file-name nil "Name of the server file")

(defvar server-name-base nil "Internal: name of the server to use as base")
(defvar server-name-prev "" "Internal: name of the server started earlier")

(require 'server)

(defadvice server-start (around sstart-around protect)
  (let ((kill-only (ad-get-arg 0))  ret  bypass (i 0)
        (sname server-name) s-dir s-file)
    (when (not kill-only)               ; killing the server
      (setq s-dir (if server-use-tcp server-auth-dir server-socket-dir))
      (setq s-file (expand-file-name sname s-dir))
      (cond ((eq server-startup 'check)
             (when (file-exists-p s-file)
               (message "File %s exists.\nPlease delete file if another emacs 
is not using it or change the value of server-name and try again." s-file)
               (setq bypass t)))
            ((eq server-startup 'search)
             (if (or (null server-name-base)
                     (not (string= server-name server-name-prev)))
                 (setq server-name-base server-name))
             (while (file-exists-p s-file)
               (setq i (1+ i))
               (setq sname (format "%s%d" server-name-base i))
               (setq s-file (expand-file-name sname s-dir))))))
    (let ((server-name sname))
      (setq ret (if bypass nil
                  ;;
                  ad-do-it
                  ;;
                  )))
    (cond (kill-only
           (if server-file-name
               (ignore-errors (delete-file server-file-name)))
           (setq server-process nil
                 server-file-name nil)
           (remove-hook 'kill-emacs-hook 'server-kill-on-exit))
          (t
           (cond (server-process
                  (setq server-name sname
                        server-name-prev sname ; if user changes it
                        server-file-name s-file)
                  (add-hook 'kill-emacs-hook 'server-kill-on-exit))
                 (t
                  (setq server-file-name nil)
                  (remove-hook 'kill-emacs-hook 'server-kill-on-exit)))))

    ret))

(defun server-kill-on-exit ()
  (when (and server-file-name server-process)
    ;; killing the server tries to close connections, which could hang.
    ;; (server-start t)                         ; kill the server
    ;; Disable new connections
    (ignore-errors (delete-file server-file-name))))

(unless (featurep 'gnuserv)
  (ad-activate 'server-start))

;;(provide 'server-x)
;; server-x.el ends here