;;; resume.el --- process command line args from within a suspended Emacs job ;; Copyright (C) 1992 Free Software Foundation, Inc. ;; Author: Joe Wells <jbw@bucsf.bu.edu> ;; Adapted-By: ESR ;; Keywords: processes ;; This file is part of GNU Emacs. ;; GNU Emacs 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 2, or (at your option) ;; any later version. ;; GNU Emacs 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 GNU Emacs; see the file COPYING. If not, write to the ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330, ;; Boston, MA 02111-1307, USA. ;;; Commentary: ;; The purpose of this library is to handle command line arguments ;; when you resume an existing Emacs job. ;; In order to use it, you must put this code in your .emacs file. ;; (add-hook 'suspend-hook 'resume-suspend-hook) ;; (add-hook 'suspend-resume-hook 'resume-process-args) ;; You can't get the benefit of this library by using the `emacs' command, ;; since that always starts a new Emacs job. Instead you must use a ;; command called `edit' which knows how to resume an existing Emacs job ;; if you have one, or start a new Emacs job if you don't have one. ;; To define the `edit' command, run the script etc/emacs.csh (if you use CSH), ;; or etc/emacs.bash if you use BASH. You would normally do this in your ;; login script. ;; Stephan Gildea suggested bug fix (gildea@bbn.com). ;; Ideas from Michael DeCorte and other people. ;;; Code: (defvar resume-emacs-args-file (expand-file-name "~/.emacs_args") "*This file is where arguments are placed for a suspended emacs job.") (defvar resume-emacs-args-buffer " *Command Line Args*" "Buffer that is used by resume-process-args.") (defun resume-process-args () "Handler for command line args given when Emacs is resumed." (let ((start-buffer (current-buffer)) (args-buffer (get-buffer-create resume-emacs-args-buffer)) length args (command-line-default-directory default-directory)) (unwind-protect (progn (set-buffer args-buffer) (erase-buffer) ;; get the contents of resume-emacs-args-file (condition-case () (let ((result (insert-file-contents resume-emacs-args-file))) (setq length (car (cdr result)))) ;; the file doesn't exist, ergo no arguments (file-error (erase-buffer) (setq length 0))) (if (<= length 0) (setq args nil) ;; get the arguments from the buffer (goto-char (point-min)) (while (not (eobp)) (skip-chars-forward " \t\n") (let ((begin (point))) (skip-chars-forward "^ \t\n") (setq args (cons (buffer-substring begin (point)) args))) (skip-chars-forward " \t\n")) ;; arguments are now in reverse order (setq args (nreverse args)) ;; make sure they're not read again (erase-buffer)) (resume-write-buffer-to-file (current-buffer) resume-emacs-args-file) ;; if nothing was in buffer, args will be null (or (null args) (setq command-line-default-directory (file-name-as-directory (car args)) args (cdr args))) ;; actually process the arguments (command-line-1 args)) ;; If the command line args don't result in a find-file, the ;; buffer will be left in args-buffer. So we change back to the ;; original buffer. The reason I don't just use ;; (let ((default-directory foo)) ;; (command-line-1 args)) ;; in the context of the original buffer is because let does not ;; work properly with buffer-local variables. (if (eq (current-buffer) args-buffer) (set-buffer start-buffer))))) ;;;###autoload (defun resume-suspend-hook () "Clear out the file used for transmitting args when Emacs resumes." (save-excursion (set-buffer (get-buffer-create resume-emacs-args-buffer)) (erase-buffer) (resume-write-buffer-to-file (current-buffer) resume-emacs-args-file))) (defun resume-write-buffer-to-file (buffer file) "Writes the contents of BUFFER into FILE, if permissions allow." (if (not (file-writable-p file)) (error "No permission to write file %s" file)) (save-excursion (set-buffer buffer) (clear-visited-file-modtime) (save-restriction (widen) (write-region (point-min) (point-max) file nil 'quiet)) (set-buffer-modified-p nil))) (provide 'resume) ;;; resume.el ends here