*** empty log message ***
[emacs.git] / lisp / time.el
blob756aa6ad8b935692adabb5d9128e6f7d007e927b
1 ;;; time.el --- display time, load and mail indicator in mode line of Emacs.
3 ;; Copyright (C) 1985, 86, 87, 93, 94, 96, 2000 Free Software Foundation, Inc.
5 ;; Maintainer: FSF
7 ;; This file is part of GNU Emacs.
9 ;; GNU Emacs is free software; you can redistribute it and/or modify
10 ;; it under the terms of the GNU General Public License as published by
11 ;; the Free Software Foundation; either version 2, or (at your option)
12 ;; any later version.
14 ;; GNU Emacs is distributed in the hope that it will be useful,
15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 ;; GNU General Public License for more details.
19 ;; You should have received a copy of the GNU General Public License
20 ;; along with GNU Emacs; see the file COPYING. If not, write to the
21 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
22 ;; Boston, MA 02111-1307, USA.
24 ;;; Commentary:
26 ;; Facilities to display current time/date and a new-mail indicator
27 ;; in the Emacs mode line. The single entry point is `display-time'.
29 ;;; Code:
31 (defgroup display-time nil
32 "Display time and load in mode line of Emacs."
33 :group 'modeline
34 :group 'mail)
37 ;;;###autoload
38 (defcustom display-time-mode nil
39 "Toggle display of time, load level, and mail flag in mode lines.
40 Setting this variable directly does not take effect;
41 use either \\[customize] or the function `display-time-mode'."
42 :set (lambda (symbol value)
43 (display-time-mode (or value 0)))
44 :initialize 'custom-initialize-default
45 :type 'boolean
46 :group 'display-time
47 :require 'time
48 :version "20.3")
51 (defcustom display-time-mail-file nil
52 "*File name of mail inbox file, for indicating existence of new mail.
53 Non-nil and not a string means don't check for mail. nil means use
54 default, which is system-dependent, and is the same as used by Rmail."
55 :type '(choice (const :tag "(None)" none)
56 (const :tag "Default" nil)
57 (file :format "%v"))
58 :group 'display-time)
60 (defcustom display-time-mail-function nil
61 "*Function to call, for indicating existence of new mail.
62 nil means use the default method of checking `display-time-mail-file'."
63 :type '(choice (const :tag "Default" nil)
64 (function))
65 :group 'display-time)
67 ;;;###autoload
68 (defcustom display-time-day-and-date nil "\
69 *Non-nil means \\[display-time] should display day and date as well as time."
70 :type 'boolean
71 :group 'display-time)
73 (defvar display-time-timer nil)
75 (defcustom display-time-interval 60
76 "*Seconds between updates of time in the mode line."
77 :type 'integer
78 :group 'display-time)
80 (defcustom display-time-24hr-format nil
81 "*Non-nil indicates time should be displayed as hh:mm, 0 <= hh <= 23.
82 Nil means 1 <= hh <= 12, and an AM/PM suffix is used."
83 :type 'boolean
84 :group 'display-time)
86 (defvar display-time-string nil)
88 (defcustom display-time-hook nil
89 "*List of functions to be called when the time is updated on the mode line."
90 :type 'hook
91 :group 'display-time)
93 (defvar display-time-server-down-time nil
94 "Time when mail file's file system was recorded to be down.
95 If that file system seems to be up, the value is nil.")
97 ;;;###autoload
98 (defun display-time ()
99 "Enable display of time, load level, and mail flag in mode lines.
100 This display updates automatically every minute.
101 If `display-time-day-and-date' is non-nil, the current day and date
102 are displayed as well.
103 This runs the normal hook `display-time-hook' after each update."
104 (interactive)
105 (display-time-mode 1))
107 ;;;###autoload
108 (defun display-time-mode (arg)
109 "Toggle display of time, load level, and mail flag in mode lines.
110 With a numeric arg, enable this display if arg is positive.
112 When this display is enabled, it updates automatically every minute.
113 If `display-time-day-and-date' is non-nil, the current day and date
114 are displayed as well.
115 This runs the normal hook `display-time-hook' after each update."
116 (interactive "P")
117 (let ((on (if (null arg)
118 (not display-time-timer)
119 (> (prefix-numeric-value arg) 0))))
120 (setq display-time-mode on)
121 (and display-time-timer (cancel-timer display-time-timer))
122 (setq display-time-timer nil)
123 (setq display-time-string "")
124 (or global-mode-string (setq global-mode-string '("")))
125 (if on
126 (progn
127 (or (memq 'display-time-string global-mode-string)
128 (setq global-mode-string
129 (append global-mode-string '(display-time-string))))
130 ;; Set up the time timer.
131 (setq display-time-timer
132 (run-at-time t display-time-interval
133 'display-time-event-handler))
134 ;; Make the time appear right away.
135 (display-time-update)
136 ;; When you get new mail, clear "Mail" from the mode line.
137 (add-hook 'rmail-after-get-new-mail-hook
138 'display-time-event-handler))
139 (remove-hook 'rmail-after-get-new-mail-hook
140 'display-time-event-handler))))
142 (defcustom display-time-mail-face 'mode-line
143 "Face to use for `display-time-mail-string'.
144 If `display-time-use-mail-icon' is non-nil, the image's background
145 colour is the background of this face. Set this to a face other than
146 `mode-line' to make the mail indicator stand out on a suitable
147 display."
148 :group 'faces
149 :group 'display-time
150 :type 'face)
152 (defvar display-time-mail-icon
153 (find-image '((:type xbm :file "letter.xbm" :ascent center)))
154 "Image specification to offer as the mail indicator on a graphic
155 display. See `display-time-use-mail-icon' and
156 `display-time-mail-face'.")
158 (defcustom display-time-use-mail-icon nil
159 "Non-nil means use an icon as the mail indicator on a graphic display.
160 Otherwise use the string \"Mail\". The icon may consume less of the
161 mode line. It is specified by `display-time-mail-icon'."
162 :group 'display-time
163 :type 'boolean)
165 (defcustom display-time-format nil
166 "*A string specifying the format for displaying the time in the mode line.
167 See the function `format-time-string' for an explanation of
168 how to write this string. If this is nil, the defaults
169 depend on `display-time-day-and-date' and `display-time-24hr-format'."
170 :type '(choice (const :tag "Default" nil)
171 string)
172 :group 'display-time)
174 (defcustom display-time-string-forms
175 '((if (and (not display-time-format) display-time-day-and-date)
176 (format-time-string "%a %b %e " now)
178 (format-time-string (or display-time-format
179 (if display-time-24hr-format "%H:%M" "%-I:%M%p"))
180 now)
181 load
182 (if mail
183 ;; Build the string every time to act on customization.
184 (concat " "
185 (propertize
186 "Mail"
187 'display `(when (and display-time-use-mail-icon
188 (display-graphic-p))
189 ,@display-time-mail-icon
190 ,@(list :background (face-attribute
191 display-time-mail-face
192 :background)))
193 'help-echo "mouse-2: Read mail"
194 'local-map (make-mode-line-mouse2-map read-mail-command)))
195 ""))
196 "*A list of expressions governing display of the time in the mode line.
197 For most purposes, you can control the time format using `display-time-format'
198 which is a more standard interface.
200 This expression is a list of expressions that can involve the keywords
201 `load', `day', `month', and `year', `12-hours', `24-hours', `minutes',
202 `seconds', all numbers in string form, and `monthname', `dayname', `am-pm',
203 and `time-zone' all alphabetic strings, and `mail' a true/nil value.
205 For example, the form
207 '((substring year -2) \"/\" month \"/\" day
208 \" \" 24-hours \":\" minutes \":\" seconds
209 (if time-zone \" (\") time-zone (if time-zone \")\")
210 (if mail \" Mail\" \"\"))
212 would give mode line times like `94/12/30 21:07:48 (UTC)'."
213 :type 'sexp
214 :group 'display-time)
216 (defun display-time-event-handler ()
217 (display-time-update)
218 ;; Do redisplay right now, if no input pending.
219 (sit-for 0)
220 (let* ((current (current-time))
221 (timer display-time-timer)
222 ;; Compute the time when this timer will run again, next.
223 (next-time (timer-relative-time
224 (list (aref timer 1) (aref timer 2) (aref timer 3))
225 (* 5 (aref timer 4)) 0)))
226 ;; If the activation time is far in the past,
227 ;; skip executions until we reach a time in the future.
228 ;; This avoids a long pause if Emacs has been suspended for hours.
229 (or (> (nth 0 next-time) (nth 0 current))
230 (and (= (nth 0 next-time) (nth 0 current))
231 (> (nth 1 next-time) (nth 1 current)))
232 (and (= (nth 0 next-time) (nth 0 current))
233 (= (nth 1 next-time) (nth 1 current))
234 (> (nth 2 next-time) (nth 2 current)))
235 (progn
236 (timer-set-time timer (timer-next-integral-multiple-of-time
237 current display-time-interval)
238 display-time-interval)
239 (timer-activate timer)))))
241 ;; Update the display-time info for the mode line
242 ;; but don't redisplay right now. This is used for
243 ;; things like Rmail `g' that want to force an update
244 ;; which can wait for the next redisplay.
245 (defun display-time-update ()
246 (let* ((now (current-time))
247 (time (current-time-string now))
248 (load (condition-case ()
249 (if (zerop (car (load-average))) ""
250 ;; The load average number is mysterious, so
251 ;; propvide some help.
252 (let ((str (format " %03d" (car (load-average)))))
253 (propertize
254 (concat (substring str 0 -2) "." (substring str -2))
255 'help-echo "System load average")))
256 (error "")))
257 (mail-spool-file (or display-time-mail-file
258 (getenv "MAIL")
259 (concat rmail-spool-directory
260 (user-login-name))))
261 (mail (or (and display-time-mail-function
262 (funcall display-time-mail-function))
263 (and (stringp mail-spool-file)
264 (or (null display-time-server-down-time)
265 ;; If have been down for 20 min, try again.
266 (> (- (nth 1 now) display-time-server-down-time)
267 1200)
268 (and (< (nth 1 now) display-time-server-down-time)
269 (> (- (nth 1 now) display-time-server-down-time)
270 -64336)))
271 (let ((start-time (current-time)))
272 (prog1
273 (display-time-file-nonempty-p mail-spool-file)
274 (if (> (- (nth 1 (current-time)) (nth 1 start-time))
276 ;; Record that mail file is not accessible.
277 (setq display-time-server-down-time
278 (nth 1 (current-time)))
279 ;; Record that mail file is accessible.
280 (setq display-time-server-down-time nil)))))))
281 (24-hours (substring time 11 13))
282 (hour (string-to-int 24-hours))
283 (12-hours (int-to-string (1+ (% (+ hour 11) 12))))
284 (am-pm (if (>= hour 12) "pm" "am"))
285 (minutes (substring time 14 16))
286 (seconds (substring time 17 19))
287 (time-zone (car (cdr (current-time-zone now))))
288 (day (substring time 8 10))
289 (year (substring time 20 24))
290 (monthname (substring time 4 7))
291 (month
292 (cdr
293 (assoc
294 monthname
295 '(("Jan" . "1") ("Feb" . "2") ("Mar" . "3") ("Apr" . "4")
296 ("May" . "5") ("Jun" . "6") ("Jul" . "7") ("Aug" . "8")
297 ("Sep" . "9") ("Oct" . "10") ("Nov" . "11") ("Dec" . "12")))))
298 (dayname (substring time 0 3)))
299 (setq display-time-string
300 (mapconcat 'eval display-time-string-forms ""))
301 ;; This is inside the let binding, but we are not going to document
302 ;; what variables are available.
303 (run-hooks 'display-time-hook))
304 (force-mode-line-update))
306 (defun display-time-file-nonempty-p (file)
307 (and (file-exists-p file)
308 (< 0 (nth 7 (file-attributes (file-chase-links file))))))
310 (if display-time-mode
311 (display-time-mode t))
313 (provide 'time)
315 ;;; time.el ends here