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+;;; saveplace.el --- automatically save place in files.
+
+;; Copyright (C) 1993 Free Software Foundation, Inc.
+
+;; Author: Karl Fogel <kfogel@cs.oberlin.edu>
+;; Maintainer: FSF
+;; Created: July, 1993
+;; Version: 1.0
+;; Keywords: bookmarks, placeholders
+
+;; 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, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+;; Automatically save place in files, so that visiting them later
+;; (even during a different Emacs session) automatically moves point
+;; to the saved position, when the file is first found.  Uses the
+;; value of buffer-local variable save-place to determine whether to
+;; save position or not.
+;;
+;; Don't autoload this, rather, load it, since it modifies
+;; find-file-hooks and other hooks.
+
+;; this is what I was using during testing:
+;; (define-key ctl-x-map "p" 'toggle-save-place)
+
+(defvar save-place-alist nil
+  "Alist of saved places to go back to when revisiting files.
+Each element looks like (FILENAME . POSITION);
+visiting file FILENAME goes automatically to position POSITION
+rather than the beginning of the buffer.
+This alist is saved between Emacs sessions.")
+
+(defvar save-place nil
+  "*Non-nil means automatically save place in each file.
+This means when you visit a file, point goes to the last place
+where it was when you previously visited the same file.
+This variable is automatically buffer-local.
+
+If you wish your place in any file to always be automatically saved,
+simply put this in your `~/.emacs' file:
+
+\(setq-default save-place t\)")
+
+(make-variable-buffer-local 'save-place)
+
+(defvar save-place-file "~/.emacs-places"
+  "*Name of the file that records `save-place-alist' value.")
+
+(defvar save-place-loaded nil
+  "Non-nil means that the `save-place-file' has been loaded.")
+
+(defun toggle-save-place (&optional parg)
+  "Toggle whether to save your place in this file between sessions.
+If this mode is enabled, point is recorded when you kill the buffer
+or exit Emacs.  Visiting this file again will go to that position,
+even in a later Emacs session.
+
+If called with a prefix arg, the mode is enabled if and only if
+the argument is positive.
+
+To save places automatically in all files, put this in your `.emacs' file:
+
+\(setq-default save-place t\)"
+  (interactive "P")
+  (if (not buffer-file-name)
+      (message 
+       (format "Buffer \"%s\" not visiting a file." (buffer-name)))
+    (if (and save-place (or (not parg) (<= parg 0)))
+	(progn
+	  (message "No place will be saved in this file.")
+	  (setq save-place nil))
+      (message "Place will be saved.")
+      (setq save-place t))))
+
+(defun save-place-to-alist ()
+  ;; put filename and point in a cons box and then cons that onto the
+  ;; front of the save-place-alist, if save-place is non-nil.
+  ;; Otherwise, just delete that file from the alist.
+  ;; first check to make sure alist has been loaded in from the master
+  ;; file.  If not, do so, then feel free to modify the alist.  It
+  ;; will be saved again when Emacs is killed.
+  (or save-place-loaded (load-save-place-alist-from-file))
+  (if buffer-file-name
+      (progn
+        (let ((cell (assoc buffer-file-name save-place-alist)))
+          (if cell
+              (setq save-place-alist (delq cell save-place-alist))))
+        (if save-place
+            (setq save-place-alist
+                  (cons (cons buffer-file-name (point))
+                        save-place-alist))))))
+
+(defun save-place-alist-to-file ()
+  (let ((file (expand-file-name save-place-file)))
+    (save-excursion
+      (message (format "Saving places to %s..." file))
+      (set-buffer (get-buffer-create " *Saved Places*"))
+      (delete-region (point-min) (point-max))
+      (if (file-readable-p file)
+          (insert-file-contents file))
+      (delete-region (point-min) (point-max))
+      (goto-char (point-min))
+      (print save-place-alist (current-buffer))
+      (write-file file)
+      (kill-buffer (current-buffer))
+      (message (format "Saving places to %s... done." file)))))
+
+(defun load-save-place-alist-from-file ()
+  (if (not save-place-loaded)
+      (progn
+        (setq save-place-loaded t)
+        (let ((file (expand-file-name save-place-file)))
+          ;; make sure that the alist does not get overwritten, and then
+          ;; load it if it exists:
+          (if (file-readable-p file)
+              (save-excursion
+                (message (format "Loading places from %s..."
+                                 save-place-file))
+                ;; don't want to use find-file because we have been
+                ;; adding hooks to it.
+                (set-buffer (get-buffer-create " *Saved Places*"))
+                (delete-region (point-min) (point-max))
+                (insert-file-contents file)
+                (goto-char (point-min))
+                (setq save-place-alist 
+                      (car (read-from-string
+                            (buffer-substring (point-min) (point-max)))))
+                (kill-buffer (current-buffer))
+                (message (format "Loading places from %s... done." file))
+                t)
+            t)
+          nil))))
+
+(defun save-places-to-alist ()
+  ;; go through buffer-list, saving places to alist if save-place is
+  ;; non-nil, deleting them from alist if it is nil.
+  (let ((buf-list (buffer-list)))
+    (while buf-list
+      ;; put this into a save-excursion in case someone is counting on
+      ;; another function in kill-emacs-hook to act on the last buffer
+      ;; they were in:
+      (save-excursion
+	(set-buffer (car buf-list))
+	;; save-place checks buffer-file-name too, but we can avoid
+	;; overhead of function call by checking here too.
+	(and buffer-file-name (save-place-to-alist))
+	(setq buf-list (cdr buf-list))))))
+    
+(add-hook 
+ 'find-file-hooks
+ (function
+  (lambda ()
+    (or save-place-loaded (load-save-place-alist-from-file))
+    (let ((cell (assoc buffer-file-name save-place-alist)))
+      (if cell
+	  (progn
+	    (goto-char (cdr cell))
+	    ;; and make sure it will be saved again for later.
+	    (setq save-place t)))))))
+
+(add-hook 'kill-emacs-hook
+	  (function
+	   (lambda ()
+	     (progn
+	       (save-places-to-alist)
+	       (save-place-alist-to-file)))))
+
+(add-hook 'kill-buffer-hook 'save-place-to-alist)
+
+(provide 'saveplace) ; why not...
+
+;;; saveplace.el ends here
+