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diff --git a/lisp/timer.el b/lisp/timer.el
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+;; Run a function with args at some time in future
+;; Copyright (C) 1990 Free Software Foundation, Inc.
+
+;; 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 1, 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.
+
+(defvar timer-process nil)
+(defvar timer-alist ())
+(defvar timer-out "")
+(defvar timer-dont-exit nil
+  ;; this is useful for functions which will be doing their own erratic
+  ;; rescheduling or people who otherwise expect to use the process frequently
+  "If non-nil, don't exit the timer process when no more events are pending.")
+
+(defun run-at-time (time repeat function &rest args)
+  "Run a function at a time, and optionally on a regular interval.
+Arguments are TIME, REPEAT, FUNCTION &rest ARGS.
+TIME, a string,  can be specified absolutely or relative to now.
+REPEAT, an integer number of seconds, is the interval on which to repeat
+the call to the function."
+  (interactive "sRun at time: \nNRepeat interval: \naFunction: ")
+  (cond ((or (not timer-process) 
+             (memq (process-status timer-process) '(exit signal nil)))
+         (if timer-process (delete-process timer-process))
+         (setq timer-process (start-process "timer" nil "timer")
+               timer-alist nil)
+         (set-process-filter   timer-process 'timer-process-filter)
+         (set-process-sentinel timer-process 'timer-process-sentinel)
+         (process-kill-without-query timer-process))
+        ((eq (process-status timer-process) 'stop)
+         (continue-process timer-process)))
+  ;; There should be a living, breathing timer process now
+  (let ((token (concat (current-time-string) "-" (length timer-alist))))
+    (send-string timer-process (concat time "\001" token "\n"))
+    (setq timer-alist (cons (list token repeat function args) timer-alist))))
+
+(defun timer-process-filter (proc str)
+  (setq timer-out (concat timer-out str))
+  (let (do token error)
+    (while (string-match "\n" timer-out)
+      (setq token (substring timer-out 0 (match-beginning 0))
+            do (assoc token timer-alist)
+            timer-out (substring timer-out (match-end 0)))
+      (cond
+       (do (apply (nth 2 do) (nth 3 do))   ; do it
+           (if (natnump (nth 1 do))        ; reschedule it
+               (send-string proc (concat (nth 1 do) " sec\001" (car do) "\n"))
+             (setq timer-alist (delq do timer-alist))))
+       ((string-match "timer: \\([^:]+\\): \\([^\001]*\\)\001\\(.*\\)$" token)
+        (setq error (substring token (match-beginning 1) (match-end 1))
+              do    (substring token (match-beginning 2) (match-end 2))
+              token (assoc (substring token (match-beginning 3) (match-end 3))
+                           timer-alist)
+              timer-alist (delq token timer-alist))
+        (ding 'no-terminate) ; using error function in process filters is rude
+        (message "%s for %s; couldn't set at \"%s\"" error (nth 2 token) do))))
+    (or timer-alist timer-dont-exit (process-send-eof proc))))
+
+(defun timer-process-sentinel (proc str)
+  (let ((stat (process-status proc)))
+    (if (eq stat 'stop) (continue-process proc)
+      ;; if it exited normally, presumably it was intentional.
+      ;; if there were no pending events, who cares that it exited?
+      (if (or (not timer-alist) (eq stat 'exit)) ()
+        (ding 'no-terminate)
+        (message "Timer exited abnormally.  All events cancelled."))
+      (setq timer-process nil timer-alist nil timer-scratch ""))))
+
+(defun cancel-timer (function)
+  "Cancel all events scheduled by ``run-at-time'' which would run FUNCTION."
+  (interactive "aCancel function: ")
+  (let ((alist timer-alist))
+    (while alist
+      (if (eq (nth 2 (car alist)) function)
+          (setq timer-alist (delq (car alist) timer-alist)))
+      (setq alist (cdr alist))))
+  (or timer-alist timer-dont-exit (process-send-eof timer-process)))
+
+(provide 'timer)