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[bpt/emacs.git] / lisp / files.el
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1;;; files.el --- file input and output commands for Emacs
2
8c0e7b73 3;; Copyright (C) 1985, 1986, 1987, 1992 Free Software Foundation, Inc.
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5;; Maintainer: FSF
6
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7;; This file is part of GNU Emacs.
8
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
e5167999 11;; the Free Software Foundation; either version 2, or (at your option)
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12;; any later version.
13
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.
18
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
21;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
22
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23;;; Code:
24
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25(defconst delete-auto-save-files t
26 "*Non-nil means delete a buffer's auto-save file when the buffer is saved.")
27
28(defconst directory-abbrev-alist
29 nil
30 "*Alist of abbreviations for file directories.
31A list of elements of the form (FROM . TO), each meaning to replace
32FROM with TO when it appears in a directory name. This replacement is
33done when setting up the default directory of a newly visited file.
34*Every* FROM string should start with `^'.
35
36Use this feature when you have directories which you normally refer to
37via absolute symbolic links. Make TO the name of the link, and FROM
38the name it is linked to.")
39
40;;; Turn off backup files on VMS since it has version numbers.
41(defconst make-backup-files (not (eq system-type 'vax-vms))
42 "*Create a backup of each file when it is saved for the first time.
43This can be done by renaming the file or by copying.
44
45Renaming means that Emacs renames the existing file so that it is a
46backup file, then writes the buffer into a new file. Any other names
47that the old file had will now refer to the backup file. The new file
48is owned by you and its group is defaulted.
49
50Copying means that Emacs copies the existing file into the backup
51file, then writes the buffer on top of the existing file. Any other
52names that the old file had will now refer to the new (edited) file.
53The file's owner and group are unchanged.
54
55The choice of renaming or copying is controlled by the variables
56`backup-by-copying', `backup-by-copying-when-linked' and
57`backup-by-copying-when-mismatch'.")
58
59;; Do this so that local variables based on the file name
60;; are not overridden by the major mode.
61(defvar backup-inhibited nil
62 "Non-nil means don't make a backup file for this buffer.")
63(put 'backup-inhibited 'permanent-local t)
64
65(defconst backup-by-copying nil
66 "*Non-nil means always use copying to create backup files.
67See documentation of variable `make-backup-files'.")
68
69(defconst backup-by-copying-when-linked nil
70 "*Non-nil means use copying to create backups for files with multiple names.
71This causes the alternate names to refer to the latest version as edited.
72This variable is relevant only if `backup-by-copying' is nil.")
73
74(defconst backup-by-copying-when-mismatch nil
75 "*Non-nil means create backups by copying if this preserves owner or group.
76Renaming may still be used (subject to control of other variables)
77when it would not result in changing the owner or group of the file;
78that is, for files which are owned by you and whose group matches
79the default for a new file created there by you.
80This variable is relevant only if `backup-by-copying' is nil.")
81
82(defvar backup-enable-predicate
83 '(lambda (name)
84 (or (< (length name) 5)
85 (not (string-equal "/tmp/" (substring name 0 5)))))
86 "Predicate that looks at a file name and decides whether to make backups.
87Called with an absolute file name as argument, it returns t to enable backup.")
88
89(defconst buffer-offer-save nil
90 "*Non-nil in a buffer means offer to save the buffer on exit
91even if the buffer is not visiting a file.
92Automatically local in all buffers.")
93(make-variable-buffer-local 'buffer-offer-save)
94
95(defconst file-precious-flag nil
96 "*Non-nil means protect against I/O errors while saving files.
97Some modes set this non-nil in particular buffers.")
98
99(defvar version-control nil
100 "*Control use of version numbers for backup files.
101t means make numeric backup versions unconditionally.
102nil means make them for files that have some already.
103never means do not make them.")
104
105(defvar dired-kept-versions 2
106 "*When cleaning directory, number of versions to keep.")
107
108(defvar trim-versions-without-asking nil
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109 "*If t, deletes excess backup versions silently.
110If nil, asks confirmation. Any other value prevents any trimming.")
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111
112(defvar kept-old-versions 2
113 "*Number of oldest versions to keep when a new numbered backup is made.")
114
115(defvar kept-new-versions 2
116 "*Number of newest versions to keep when a new numbered backup is made.
117Includes the new backup. Must be > 0")
118
119(defconst require-final-newline nil
120 "*Value of t says silently ensure a file ends in a newline when it is saved.
121Non-nil but not t says ask user whether to add a newline when there isn't one.
122nil means don't add newlines.")
123
124(defconst auto-save-default t
125 "*Non-nil says by default do auto-saving of every file-visiting buffer.")
126
127(defconst auto-save-visited-file-name nil
128 "*Non-nil says auto-save a buffer in the file it is visiting, when practical.
129Normally auto-save files are written under other names.")
130
131(defconst save-abbrevs nil
132 "*Non-nil means save word abbrevs too when files are saved.
133Loading an abbrev file sets this to t.")
134
135(defconst find-file-run-dired t
136 "*Non-nil says run dired if find-file is given the name of a directory.")
137
138(put 'find-file-not-found-hooks 'permanent-local t)
139(defvar find-file-not-found-hooks nil
140 "List of functions to be called for `find-file' on nonexistent file.
141These functions are called as soon as the error is detected.
142`buffer-file-name' is already set up.
143The functions are called in the order given until one of them returns non-nil.")
144
145(put 'find-file-hooks 'permanent-local t)
146(defvar find-file-hooks nil
147 "List of functions to be called after a buffer is loaded from a file.
148The buffer's local variables (if any) will have been processed before the
149functions are called.")
150
151(put 'write-file-hooks 'permanent-local t)
152(defvar write-file-hooks nil
153 "List of functions to be called before writing out a buffer to a file.
154If one of them returns non-nil, the file is considered already written
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155and the rest are not called.
156These hooks are considered to pertain to the visited file.
157So this list is cleared if you change the visited file name.
158See also `write-contents-hooks'.")
159
160(defvar write-contents-hooks nil
161 "List of functions to be called before writing out a buffer to a file.
162If one of them returns non-nil, the file is considered already written
163and the rest are not called.
164These hooks are considered to pertain to the buffer's contents,
165not to the particular visited file; thus, `set-visited-file-name' does
166not clear this variable, but changing the major mode does clear it.
167See also `write-file-hooks'.")
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168
169(defconst enable-local-variables t
170 "*Control use of local-variables lists in files you visit.
171The value can be t, nil or something else.
172A value of t means local-variables lists are obeyed;
173nil means they are ignored; anything else means query.
174
175The command \\[normal-mode] always obeys local-variables lists
176and ignores this variable.")
177
2bba782c 178(defconst enable-local-eval 'maybe
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179 "*Control processing of the \"variable\" `eval' in a file's local variables.
180The value can be t, nil or something else.
181A value of t means obey `eval' variables;
182nil means ignore them; anything else means query.
183
184The command \\[normal-mode] always obeys local-variables lists
185and ignores this variable.")
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186
187;; Avoid losing in versions where CLASH_DETECTION is disabled.
188(or (fboundp 'lock-buffer)
189 (fset 'lock-buffer 'ignore))
190(or (fboundp 'unlock-buffer)
191 (fset 'unlock-buffer 'ignore))
192\f
193(defun pwd ()
194 "Show the current default directory."
195 (interactive nil)
196 (message "Directory %s" default-directory))
197
198(defun cd (dir)
199 "Make DIR become the current buffer's default directory."
200 (interactive "DChange default directory: ")
201 (setq dir (expand-file-name dir))
202 (if (not (eq system-type 'vax-vms))
203 (setq dir (file-name-as-directory dir)))
204 (if (not (file-directory-p dir))
205 (error "%s is not a directory" dir)
206 (if (file-executable-p dir)
207 (setq default-directory dir)
208 (error "Cannot cd to %s: Permission denied" dir)))
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209 ;; We used to call pwd at this point. That's not terribly helpful
210 ;; when we're invoking cd interactively, and the new cmushell-based
211 ;; shell has its own (better) facilities for this.
212)
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213
214(defun load-file (file)
215 "Load the Lisp file named FILE."
216 (interactive "fLoad file: ")
217 (load (expand-file-name file) nil nil t))
218
219(defun load-library (library)
220 "Load the library named LIBRARY.
221This is an interface to the function `load'."
222 (interactive "sLoad library: ")
223 (load library))
224\f
225(defun switch-to-buffer-other-window (buffer)
226 "Select buffer BUFFER in another window."
227 (interactive "BSwitch to buffer in other window: ")
228 (let ((pop-up-windows t))
229 (pop-to-buffer buffer t)))
230
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231(defun switch-to-buffer-other-frame (buffer)
232 "Switch to buffer BUFFER in another frame."
233 (interactive "BSwitch to buffer in other frame: ")
234 (let ((pop-up-frames t))
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235 (pop-to-buffer buffer)))
236
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237(defun find-file (filename)
238 "Edit file FILENAME.
239Switch to a buffer visiting file FILENAME,
240creating one if none already exists."
241 (interactive "FFind file: ")
242 (switch-to-buffer (find-file-noselect filename)))
243
244(defun find-file-other-window (filename)
245 "Edit file FILENAME, in another window.
246May create a new window, or reuse an existing one.
247See the function `display-buffer'."
248 (interactive "FFind file in other window: ")
249 (switch-to-buffer-other-window (find-file-noselect filename)))
250
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251(defun find-file-other-frame (filename)
252 "Edit file FILENAME, in another frame.
253May create a new frame, or reuse an existing one.
5bbbceb1 254See the function `display-buffer'."
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255 (interactive "FFind file in other frame: ")
256 (switch-to-buffer-other-frame (find-file-noselect filename)))
5bbbceb1 257
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258(defun find-file-read-only (filename)
259 "Edit file FILENAME but don't allow changes.
260Like \\[find-file] but marks buffer as read-only.
261Use \\[toggle-read-only] to permit editing."
262 (interactive "fFind file read-only: ")
263 (find-file filename)
264 (setq buffer-read-only t))
265
266(defun find-file-read-only-other-window (filename)
267 "Edit file FILENAME in another window but don't allow changes.
268Like \\[find-file-other-window] but marks buffer as read-only.
269Use \\[toggle-read-only] to permit editing."
270 (interactive "fFind file read-only other window: ")
271 (find-file filename)
272 (setq buffer-read-only t))
273
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274(defun find-file-read-only-other-frame (filename)
275 "Edit file FILENAME in another frame but don't allow changes.
276Like \\[find-file-other-frame] but marks buffer as read-only.
5bbbceb1 277Use \\[toggle-read-only] to permit editing."
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278 (interactive "fFind file read-only other frame: ")
279 (find-file-other-frame filename)
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280 (setq buffer-read-only t))
281
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282(defun find-alternate-file (filename)
283 "Find file FILENAME, select its buffer, kill previous buffer.
284If the current buffer now contains an empty file that you just visited
285\(presumably by mistake), use this command to visit the file you really want."
286 (interactive
287 (let ((file buffer-file-name)
288 (file-name nil)
289 (file-dir nil))
290 (and file
291 (setq file-name (file-name-nondirectory file)
292 file-dir (file-name-directory file)))
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293 (list (read-file-name
294 "Find alternate file: " file-dir nil nil file-name))))
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295 (and (buffer-modified-p)
296 ;; (not buffer-read-only)
297 (not (yes-or-no-p (format "Buffer %s is modified; kill anyway? "
298 (buffer-name))))
299 (error "Aborted"))
300 (let ((obuf (current-buffer))
301 (ofile buffer-file-name)
302 (oname (buffer-name)))
303 (rename-buffer " **lose**")
304 (setq buffer-file-name nil)
305 (unwind-protect
306 (progn
307 (unlock-buffer)
308 (find-file filename))
309 (cond ((eq obuf (current-buffer))
310 (setq buffer-file-name ofile)
311 (lock-buffer)
312 (rename-buffer oname))))
313 (or (eq (current-buffer) obuf)
314 (kill-buffer obuf))))
315
316(defun create-file-buffer (filename)
317 "Create a suitably named buffer for visiting FILENAME, and return it.
318FILENAME (sans directory) is used unchanged if that name is free;
319otherwise a string <2> or <3> or ... is appended to get an unused name."
320 (let ((lastname (file-name-nondirectory filename)))
321 (if (string= lastname "")
322 (setq lastname filename))
323 (generate-new-buffer lastname)))
324
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325(defun generate-new-buffer (name)
326 "Create and return a buffer with a name based on NAME.
327Choose the buffer's name using generate-new-buffer-name."
328 (get-buffer-create (generate-new-buffer-name name)))
329
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330(defconst automount-dir-prefix "^/tmp_mnt/"
331 "Regexp to match the automounter prefix in a directory name.")
332
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333(defun abbreviate-file-name (filename)
334 "Return a version of FILENAME shortened using directory-abbrev-alist.
335This also substitutes \"~\" for the user's home directory.
336See \\[describe-variable] directory-abbrev-alist RET for more information."
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337 ;; Get rid of the prefixes added by the automounter.
338 (if (and (string-match automount-dir-prefix filename)
339 (file-exists-p (file-name-directory
340 (substring filename (1- (match-end 0))))))
341 (setq filename (substring filename (1- (match-end 0)))))
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342 (let ((tail directory-abbrev-alist))
343 (while tail
344 (if (string-match (car (car tail)) filename)
345 (setq filename
346 (concat (cdr (car tail)) (substring filename (match-end 0)))))
347 (setq tail (cdr tail)))
348 (if (string-match (concat "^" (expand-file-name "~")) filename)
349 (setq filename
350 (concat "~" (substring filename (match-end 0)))))
351 filename))
352
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353(defun find-file-noselect (filename &optional nowarn)
354 "Read file FILENAME into a buffer and return the buffer.
355If a buffer exists visiting FILENAME, return that one, but
356verify that the file has not changed since visited or saved.
357The buffer is not selected, just returned to the caller."
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358 (setq filename
359 (abbreviate-file-name
360 (expand-file-name filename)))
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361 (if (file-directory-p filename)
362 (if find-file-run-dired
363 (dired-noselect filename)
364 (error "%s is a directory." filename))
365 (let ((buf (get-file-buffer filename))
366 error)
367 (if buf
368 (or nowarn
369 (verify-visited-file-modtime buf)
370 (cond ((not (file-exists-p filename))
371 (error "File %s no longer exists!" filename))
372 ((yes-or-no-p
373 (format
374 (if (buffer-modified-p buf)
375 "File %s changed on disk. Discard your edits? "
376 "File %s changed on disk. Read the new version? ")
377 (file-name-nondirectory filename)))
378 (save-excursion
379 (set-buffer buf)
380 (revert-buffer t t)))))
381 (save-excursion
382 (let* ((link-name (car (file-attributes filename)))
383 (linked-buf (and (stringp link-name)
384 (get-file-buffer link-name))))
385 (if (bufferp linked-buf)
386 (message "Symbolic link to file in buffer %s"
387 (buffer-name linked-buf))))
388 (setq buf (create-file-buffer filename))
389 (set-buffer buf)
390 (erase-buffer)
391 (condition-case ()
392 (insert-file-contents filename t)
393 (file-error
394 (setq error t)
395 ;; Run find-file-not-found-hooks until one returns non-nil.
396 (let ((hooks find-file-not-found-hooks))
397 (while (and hooks
398 (not (funcall (car hooks))))
399 (setq hooks (cdr hooks))))))
400 ;; Set buffer's default directory to that of the file.
401 (setq default-directory (file-name-directory filename))
402 ;; Turn off backup files for certain file names. Since
403 ;; this is a permanent local, the major mode won't eliminate it.
404 (and (not (funcall backup-enable-predicate buffer-file-name))
405 (progn
406 (make-local-variable 'backup-inhibited)
407 (setq backup-inhibited t)))
408 (after-find-file error (not nowarn))))
409 buf)))
410\f
411(defun after-find-file (&optional error warn)
412 "Called after finding a file and by the default revert function.
413Sets buffer mode, parses local variables.
414Optional args ERROR and WARN: ERROR non-nil means there was an
415error in reading the file. WARN non-nil means warn if there
416exists an auto-save file more recent than the visited file.
417Finishes by calling the functions in `find-file-hooks'."
418 (setq buffer-read-only (not (file-writable-p buffer-file-name)))
419 (if noninteractive
420 nil
421 (let* (not-serious
422 (msg
423 (cond ((and error (file-attributes buffer-file-name))
424 (setq buffer-read-only t)
425 "File exists, but is read-protected.")
426 ((not buffer-read-only)
427 (if (and warn
428 (file-newer-than-file-p (make-auto-save-file-name)
429 buffer-file-name))
430 "Auto save file is newer; consider M-x recover-file"
431 (setq not-serious t)
432 (if error "(New file)" nil)))
433 ((not error)
434 (setq not-serious t)
435 "Note: file is write protected")
436 ((file-attributes (directory-file-name default-directory))
437 "File not found and directory write-protected")
438 (t
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439 ;; If the directory the buffer is in doesn't exist,
440 ;; offer to create it. It's better to do this now
441 ;; than when we save the buffer, because we want
442 ;; autosaving to work.
443 (setq buffer-read-only nil)
444 (or (file-exists-p (file-name-directory buffer-file-name))
445 (if (yes-or-no-p
446 (format
447 "The directory containing %s does not exist. Create? "
448 (abbreviate-file-name buffer-file-name)))
449 (make-directory-path
450 (file-name-directory buffer-file-name))))
451 nil))))
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452 (if msg
453 (progn
454 (message msg)
455 (or not-serious (sit-for 1 nil t)))))
456 (if auto-save-default
457 (auto-save-mode t)))
458 (normal-mode t)
459 (mapcar 'funcall find-file-hooks))
460
461(defun normal-mode (&optional find-file)
462 "Choose the major mode for this buffer automatically.
463Also sets up any specified local variables of the file.
464Uses the visited file name, the -*- line, and the local variables spec.
465
466This function is called automatically from `find-file'. In that case,
467we may set up specified local variables depending on the value of
468`enable-local-variables': if it is t, we do; if it is nil, we don't;
469otherwise, we query. `enable-local-variables' is ignored if you
470run `normal-mode' explicitly."
471 (interactive)
472 (or find-file (funcall (or default-major-mode 'fundamental-mode)))
473 (condition-case err
474 (set-auto-mode)
475 (error (message "File mode specification error: %s"
476 (prin1-to-string err))))
477 (condition-case err
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478 (let ((enable-local-variables (or (not find-file)
479 enable-local-variables)))
480 (hack-local-variables))
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481 (error (message "File local-variables error: %s"
482 (prin1-to-string err)))))
483
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484(defvar auto-mode-alist (mapcar 'purecopy
485 '(("\\.text\\'" . text-mode)
486 ("\\.c\\'" . c-mode)
487 ("\\.h\\'" . c-mode)
488 ("\\.tex\\'" . TeX-mode)
489 ("\\.ltx\\'" . LaTeX-mode)
490 ("\\.el\\'" . emacs-lisp-mode)
491 ("\\.mm\\'" . nroff-mode)
492 ("\\.me\\'" . nroff-mode)
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493 ("\\.scm\\'" . scheme-mode)
494 ("\\.l\\'" . lisp-mode)
495 ("\\.lisp\\'" . lisp-mode)
496 ("\\.f\\'" . fortran-mode)
497 ("\\.for\\'" . fortran-mode)
498 ("\\.mss\\'" . scribe-mode)
499 ("\\.pl\\'" . prolog-mode)
500 ("\\.cc\\'" . c++-mode)
501 ("\\.C\\'" . c++-mode)
502;;; Less common extensions come here
503;;; so more common ones above are found faster.
504 ("\\.s\\'" . asm-mode)
505 ("ChangeLog\\'" . change-log-mode)
7adc58e5 506 ("ChangeLog.[0-9]+\\'" . change-log-mode)
7b3f3dc2 507 ("\\$CHANGE_LOG\\$\\.TXT" . change-log-mode)
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508;; The following should come after the ChangeLog pattern
509;; for the sake of ChangeLog.1, etc.
510 ("\\.[12345678]\\'" . nroff-mode)
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511 ("\\.TeX\\'" . TeX-mode)
512 ("\\.sty\\'" . LaTeX-mode)
513 ("\\.bbl\\'" . LaTeX-mode)
514 ("\\.bib\\'" . bibtex-mode)
515 ("\\.article\\'" . text-mode)
516 ("\\.letter\\'" . text-mode)
517 ("\\.texinfo\\'" . texinfo-mode)
fd5285f3 518 ("\\.texi\\'" . texinfo-mode)
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519 ("\\.lsp\\'" . lisp-mode)
520 ("\\.awk\\'" . awk-mode)
521 ("\\.prolog\\'" . prolog-mode)
522 ;; Mailer puts message to be edited in
523 ;; /tmp/Re.... or Message
524 ("^/tmp/Re" . text-mode)
525 ("/Message[0-9]*\\'" . text-mode)
526 ;; some news reader is reported to use this
527 ("^/tmp/fol/" . text-mode)
528 ("\\.y\\'" . c-mode)
529 ("\\.oak\\'" . scheme-mode)
530 ("\\.scm.[0-9]*\\'" . scheme-mode)
531 ;; .emacs following a directory delimiter
532 ;; in either Unix or VMS syntax.
533 ("[]>:/]\\..*emacs\\'" . emacs-lisp-mode)
534 ("\\.ml\\'" . lisp-mode)))
535 "\
536Alist of filename patterns vs corresponding major mode functions.
537Each element looks like (REGEXP . FUNCTION).
538Visiting a file whose name matches REGEXP causes FUNCTION to be called.")
539
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540(defun set-auto-mode ()
541 "Select major mode appropriate for current buffer.
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542This checks for a -*- mode tag in the buffer's text, or
543compares the filename against the entries in auto-mode-alist. It does
544not check for the \"mode:\" local variable in the Local Variables
545section of the file; for that, use `hack-local-variables'.
546
547If enable-local-variables is nil, this function will not check for a
548-*- mode tag."
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549 ;; Look for -*-MODENAME-*- or -*- ... mode: MODENAME; ... -*-
550 (let (beg end mode)
551 (save-excursion
552 (goto-char (point-min))
553 (skip-chars-forward " \t\n")
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554 (if (and enable-local-variables
555 (search-forward "-*-" (save-excursion (end-of-line) (point)) t)
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556 (progn
557 (skip-chars-forward " \t")
558 (setq beg (point))
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559 (search-forward "-*-"
560 (save-excursion (end-of-line) (point))
561 t))
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562 (progn
563 (forward-char -3)
564 (skip-chars-backward " \t")
565 (setq end (point))
566 (goto-char beg)
567 (if (search-forward ":" end t)
568 (progn
569 (goto-char beg)
570 (if (let ((case-fold-search t))
571 (search-forward "mode:" end t))
572 (progn
573 (skip-chars-forward " \t")
574 (setq beg (point))
575 (if (search-forward ";" end t)
576 (forward-char -1)
577 (goto-char end))
578 (skip-chars-backward " \t")
579 (setq mode (buffer-substring beg (point))))))
580 (setq mode (buffer-substring beg end)))))
581 (setq mode (intern (concat (downcase mode) "-mode")))
582 (let ((alist auto-mode-alist)
583 (name buffer-file-name))
584 (let ((case-fold-search (eq system-type 'vax-vms)))
585 ;; Remove backup-suffixes from file name.
586 (setq name (file-name-sans-versions name))
587 ;; Find first matching alist entry.
588 (while (and (not mode) alist)
589 (if (string-match (car (car alist)) name)
590 (setq mode (cdr (car alist))))
591 (setq alist (cdr alist)))))))
592 (if mode (funcall mode))))
593
7b3f3dc2 594(defun hack-local-variables ()
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595 "Parse (and bind or evaluate as appropriate) any local variables
596for current buffer."
597 ;; Look for "Local variables:" line in last page.
598 (save-excursion
599 (goto-char (point-max))
600 (search-backward "\n\^L" (max (- (point-max) 3000) (point-min)) 'move)
601 (if (let ((case-fold-search t))
602 (and (search-forward "Local Variables:" nil t)
7b3f3dc2 603 (or (eq enable-local-variables t)
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604 (and enable-local-variables
605 (save-window-excursion
606 (switch-to-buffer (current-buffer))
607 (save-excursion
608 (beginning-of-line)
609 (set-window-start (selected-window) (point)))
610 (y-or-n-p (format "Set local variables as specified at end of %s? "
611 (file-name-nondirectory buffer-file-name))))))))
612 (let ((continue t)
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613 prefix prefixlen suffix beg
614 (enable-local-eval enable-local-eval))
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615 ;; The prefix is what comes before "local variables:" in its line.
616 ;; The suffix is what comes after "local variables:" in its line.
617 (skip-chars-forward " \t")
618 (or (eolp)
619 (setq suffix (buffer-substring (point)
620 (progn (end-of-line) (point)))))
621 (goto-char (match-beginning 0))
622 (or (bolp)
623 (setq prefix
624 (buffer-substring (point)
625 (progn (beginning-of-line) (point)))))
7b3f3dc2 626
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627 (if prefix (setq prefixlen (length prefix)
628 prefix (regexp-quote prefix)))
629 (if suffix (setq suffix (concat (regexp-quote suffix) "$")))
630 (while continue
631 ;; Look at next local variable spec.
632 (if selective-display (re-search-forward "[\n\C-m]")
633 (forward-line 1))
634 ;; Skip the prefix, if any.
635 (if prefix
636 (if (looking-at prefix)
637 (forward-char prefixlen)
638 (error "Local variables entry is missing the prefix")))
639 ;; Find the variable name; strip whitespace.
640 (skip-chars-forward " \t")
641 (setq beg (point))
642 (skip-chars-forward "^:\n")
643 (if (eolp) (error "Missing colon in local variables entry"))
644 (skip-chars-backward " \t")
645 (let* ((str (buffer-substring beg (point)))
646 (var (read str))
647 val)
648 ;; Setting variable named "end" means end of list.
649 (if (string-equal (downcase str) "end")
650 (setq continue nil)
651 ;; Otherwise read the variable value.
652 (skip-chars-forward "^:")
653 (forward-char 1)
654 (setq val (read (current-buffer)))
655 (skip-chars-backward "\n")
656 (skip-chars-forward " \t")
657 (or (if suffix (looking-at suffix) (eolp))
658 (error "Local variables entry is terminated incorrectly"))
659 ;; Set the variable. "Variables" mode and eval are funny.
660 (cond ((eq var 'mode)
661 (funcall (intern (concat (downcase (symbol-name val))
662 "-mode"))))
663 ((eq var 'eval)
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664 (if (and (not (string= (user-login-name) "root"))
665 (or (eq enable-local-eval t)
666 (and enable-local-eval
667 (save-window-excursion
668 (switch-to-buffer (current-buffer))
669 (save-excursion
670 (beginning-of-line)
671 (set-window-start (selected-window) (point)))
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672 (setq enable-local-eval
673 (y-or-n-p (format "Process `eval' local variable in file %s? "
674 (file-name-nondirectory buffer-file-name))))))))
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675 (save-excursion (eval val))
676 (message "Ignoring `eval:' in file's local variables")))
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677 (t (make-local-variable var)
678 (set var val))))))))))
679\f
680(defun set-visited-file-name (filename)
681 "Change name of file visited in current buffer to FILENAME.
682The next time the buffer is saved it will go in the newly specified file.
683nil or empty string as argument means make buffer not be visiting any file.
684Remember to delete the initial contents of the minibuffer
685if you wish to pass an empty string as the argument."
686 (interactive "FSet visited file name: ")
687 (if filename
688 (setq filename
689 (if (string-equal filename "")
690 nil
691 (expand-file-name filename))))
692 (or (equal filename buffer-file-name)
693 (null filename)
694 (progn
695 (lock-buffer filename)
696 (unlock-buffer)))
697 (setq buffer-file-name filename)
698 (if filename ; make buffer name reflect filename.
5bbbceb1 699 (let ((new-name (file-name-nondirectory buffer-file-name)))
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700 (if (string= new-name "")
701 (error "Empty file name"))
702 (if (eq system-type 'vax-vms)
703 (setq new-name (downcase new-name)))
704 (setq default-directory (file-name-directory buffer-file-name))
5bbbceb1 705 (rename-buffer new-name t)))
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706 (setq buffer-backed-up nil)
707 (clear-visited-file-modtime)
708 ;; write-file-hooks is normally used for things like ftp-find-file
709 ;; that visit things that are not local files as if they were files.
710 ;; Changing to visit an ordinary local file instead should flush the hook.
711 (kill-local-variable 'write-file-hooks)
712 (kill-local-variable 'revert-buffer-function)
713 (kill-local-variable 'backup-inhibited)
714 ;; Turn off backup files for certain file names.
715 ;; Since this is a permanent local, the major mode won't eliminate it.
716 (and (not (funcall backup-enable-predicate buffer-file-name))
717 (progn
718 (make-local-variable 'backup-inhibited)
719 (setq backup-inhibited t)))
720 ;; If auto-save was not already on, turn it on if appropriate.
721 (if (not buffer-auto-save-file-name)
722 (auto-save-mode (and buffer-file-name auto-save-default)))
723 (if buffer-file-name
724 (set-buffer-modified-p t)))
725
726(defun write-file (filename)
727 "Write current buffer into file FILENAME.
728Makes buffer visit that file, and marks it not modified."
729;; (interactive "FWrite file: ")
730 (interactive
731 (list (if buffer-file-name
732 (read-file-name "Write file: "
733 nil nil nil nil)
734 (read-file-name "Write file: "
735 (cdr (assq 'default-directory
736 (buffer-local-variables)))
737 nil nil (buffer-name)))))
738 (or (null filename) (string-equal filename "")
739 (set-visited-file-name filename))
740 (set-buffer-modified-p t)
741 (save-buffer))
742\f
743(defun backup-buffer ()
744 "Make a backup of the disk file visited by the current buffer, if appropriate.
745This is normally done before saving the buffer the first time.
746If the value is non-nil, it is the result of `file-modes' on the original
747file; this means that the caller, after saving the buffer, should change
748the modes of the new file to agree with the old modes."
749 (if (and make-backup-files (not backup-inhibited)
750 (not buffer-backed-up)
751 (file-exists-p buffer-file-name)
752 (memq (aref (elt (file-attributes buffer-file-name) 8) 0)
753 '(?- ?l)))
754 (let ((real-file-name buffer-file-name)
755 backup-info backupname targets setmodes)
756 ;; If specified name is a symbolic link, chase it to the target.
757 ;; Thus we make the backups in the directory where the real file is.
758 (while (let ((tem (file-symlink-p real-file-name)))
759 (if tem
760 (setq real-file-name
761 (expand-file-name tem
762 (file-name-directory real-file-name))))
763 tem))
764 (setq backup-info (find-backup-file-name real-file-name)
765 backupname (car backup-info)
766 targets (cdr backup-info))
767;;; (if (file-directory-p buffer-file-name)
768;;; (error "Cannot save buffer in directory %s" buffer-file-name))
769 (condition-case ()
770 (let ((delete-old-versions
771 ;; If have old versions to maybe delete,
772 ;; ask the user to confirm now, before doing anything.
773 ;; But don't actually delete til later.
774 (and targets
6d74b528 775 (or (eq trim-versions-without-asking t) (eq trim-versions-without-asking nil))
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776 (or trim-versions-without-asking
777 (y-or-n-p (format "Delete excess backup versions of %s? "
778 real-file-name))))))
779 ;; Actually write the back up file.
780 (condition-case ()
781 (if (or file-precious-flag
782; (file-symlink-p buffer-file-name)
783 backup-by-copying
784 (and backup-by-copying-when-linked
785 (> (file-nlinks real-file-name) 1))
786 (and backup-by-copying-when-mismatch
787 (let ((attr (file-attributes real-file-name)))
788 (or (nth 9 attr)
789 (/= (nth 2 attr) (user-uid))))))
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790 (condition-case ()
791 (copy-file real-file-name backupname t t)
792 (file-error
793 ;; If copying fails because file BACKUPNAME
794 ;; is not writable, delete that file and try again.
795 (if (and (file-exists-p backupname)
796 (not (file-writable-p backupname)))
797 (delete-file backupname))
798 (copy-file real-file-name backupname t t)))
799 ;; rename-file should delete old backup.
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800 (rename-file real-file-name backupname t)
801 (setq setmodes (file-modes backupname)))
802 (file-error
803 ;; If trouble writing the backup, write it in ~.
804 (setq backupname (expand-file-name "~/%backup%~"))
805 (message "Cannot write backup file; backing up in ~/%%backup%%~")
806 (sleep-for 1)
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807 (condition-case ()
808 (copy-file real-file-name backupname t t)
809 (file-error
810 ;; If copying fails because file BACKUPNAME
811 ;; is not writable, delete that file and try again.
812 (if (and (file-exists-p backupname)
813 (not (file-writable-p backupname)))
814 (delete-file backupname))
815 (copy-file real-file-name backupname t t)))))
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816 (setq buffer-backed-up t)
817 ;; Now delete the old versions, if desired.
818 (if delete-old-versions
819 (while targets
820 (condition-case ()
821 (delete-file (car targets))
822 (file-error nil))
823 (setq targets (cdr targets))))
824 setmodes)
825 (file-error nil)))))
826
c3554e95 827(defun file-name-sans-versions (name &optional keep-backup-version)
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828 "Return FILENAME sans backup versions or strings.
829This is a separate procedure so your site-init or startup file can
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830redefine it.
831If the optional argument KEEP-BACKUP-VERSION is non-nil,
832we do not remove backup version numbers, only true file version numbers."
833 (let (handler (handlers file-name-handler-alist))
834 (while (and (consp handlers) (null handler))
835 (if (and (consp (car handlers))
836 (stringp (car (car handlers)))
837 (string-match (car (car handlers)) name))
838 (setq handler (cdr (car handlers))))
839 (setq handlers (cdr handlers)))
840 (if handler
841 (funcall handler 'file-name-sans-versions name keep-backup-version)
842 (substring name 0
843 (if (eq system-type 'vax-vms)
844 ;; VMS version number is (a) semicolon, optional
845 ;; sign, zero or more digits or (b) period, option
846 ;; sign, zero or more digits, provided this is the
847 ;; second period encountered outside of the
848 ;; device/directory part of the file name.
849 (or (string-match ";[---+]?[0-9]*\\'" name)
850 (if (string-match "\\.[^]>:]*\\(\\.[---+]?[0-9]*\\)\\'"
851 name)
852 (match-beginning 1))
853 (length name))
854 (if keep-backup-version
855 (length name)
856 (or (string-match "\\.~[0-9]+~\\'" name)
857 (string-match "~\\'" name)
858 (length name))))))))
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859
860(defun make-backup-file-name (file)
861 "Create the non-numeric backup file name for FILE.
862This is a separate function so you can redefine it for customization."
863 (concat file "~"))
864
865(defun backup-file-name-p (file)
866 "Return non-nil if FILE is a backup file name (numeric or not).
867This is a separate function so you can redefine it for customization.
868You may need to redefine `file-name-sans-versions' as well."
869 (string-match "~$" file))
870
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871;; This is used in various files.
872;; The usage of bv-length is not very clean,
873;; but I can't see a good alternative,
874;; so as of now I am leaving it alone.
875(defun backup-extract-version (fn)
876 "Given the name of a numeric backup file, return the backup number.
877Uses the free variable `bv-length', whose value should be
878the index in the name where the version number begins."
879 (if (and (string-match "[0-9]+~$" fn bv-length)
880 (= (match-beginning 0) bv-length))
881 (string-to-int (substring fn bv-length -1))
882 0))
883
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884;; I believe there is no need to alter this behavior for VMS;
885;; since backup files are not made on VMS, it should not get called.
886(defun find-backup-file-name (fn)
887 "Find a file name for a backup file, and suggestions for deletions.
888Value is a list whose car is the name for the backup file
889 and whose cdr is a list of old versions to consider deleting now."
890 (if (eq version-control 'never)
891 (list (make-backup-file-name fn))
892 (let* ((base-versions (concat (file-name-nondirectory fn) ".~"))
893 (bv-length (length base-versions))
894 (possibilities (file-name-all-completions
895 base-versions
896 (file-name-directory fn)))
79058860 897 (versions (sort (mapcar
2d051399 898 (function backup-extract-version)
79058860 899 possibilities)
b4da00e9 900 '<))
5bbbceb1 901 (high-water-mark (apply 'max 0 versions))
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902 (deserve-versions-p
903 (or version-control
904 (> high-water-mark 0)))
905 (number-to-delete (- (length versions)
906 kept-old-versions kept-new-versions -1)))
907 (if (not deserve-versions-p)
908 (list (make-backup-file-name fn))
909 (cons (concat fn ".~" (int-to-string (1+ high-water-mark)) "~")
910 (if (> number-to-delete 0)
911 (mapcar (function (lambda (n)
912 (concat fn ".~" (int-to-string n) "~")))
913 (let ((v (nthcdr kept-old-versions versions)))
914 (rplacd (nthcdr (1- number-to-delete) v) ())
915 v))))))))
916
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917(defun file-nlinks (filename)
918 "Return number of names file FILENAME has."
919 (car (cdr (file-attributes filename))))
920\f
921(defun save-buffer (&optional args)
922 "Save current buffer in visited file if modified. Versions described below.
923By default, makes the previous version into a backup file
924 if previously requested or if this is the first save.
925With 1 or 3 \\[universal-argument]'s, marks this version
926 to become a backup when the next save is done.
927With 2 or 3 \\[universal-argument]'s,
928 unconditionally makes the previous version into a backup file.
929With argument of 0, never makes the previous version into a backup file.
930
931If a file's name is FOO, the names of its numbered backup versions are
932 FOO.~i~ for various integers i. A non-numbered backup file is called FOO~.
933Numeric backups (rather than FOO~) will be made if value of
934 `version-control' is not the atom `never' and either there are already
935 numeric versions of the file being backed up, or `version-control' is
936 non-nil.
937We don't want excessive versions piling up, so there are variables
938 `kept-old-versions', which tells Emacs how many oldest versions to keep,
939 and `kept-new-versions', which tells how many newest versions to keep.
940 Defaults are 2 old versions and 2 new.
941`dired-kept-versions' controls dired's clean-directory (.) command.
942If `trim-versions-without-asking' is nil, system will query user
943 before trimming versions. Otherwise it does it silently."
944 (interactive "p")
945 (let ((modp (buffer-modified-p))
946 (large (> (buffer-size) 50000))
947 (make-backup-files (and make-backup-files (not (eq args 0)))))
948 (and modp (memq args '(16 64)) (setq buffer-backed-up nil))
949 (if (and modp large) (message "Saving file %s..." (buffer-file-name)))
950 (basic-save-buffer)
951 (and modp (memq args '(4 64)) (setq buffer-backed-up nil))))
952
953(defun delete-auto-save-file-if-necessary (&optional force)
954 "Delete auto-save file for current buffer if `delete-auto-save-files' is t.
955Normally delete only if the file was written by this Emacs since
956the last real save, but optional arg FORCE non-nil means delete anyway."
957 (and buffer-auto-save-file-name delete-auto-save-files
958 (not (string= buffer-file-name buffer-auto-save-file-name))
959 (or force (recent-auto-save-p))
960 (progn
961 (condition-case ()
962 (delete-file buffer-auto-save-file-name)
963 (file-error nil))
964 (set-buffer-auto-saved))))
965
966(defun basic-save-buffer ()
967 "Save the current buffer in its visited file, if it has been modified."
968 (interactive)
969 (if (buffer-modified-p)
970 (let ((recent-save (recent-auto-save-p))
971 setmodes tempsetmodes)
972 ;; On VMS, rename file and buffer to get rid of version number.
973 (if (and (eq system-type 'vax-vms)
974 (not (string= buffer-file-name
975 (file-name-sans-versions buffer-file-name))))
976 (let (buffer-new-name)
977 ;; Strip VMS version number before save.
978 (setq buffer-file-name
979 (file-name-sans-versions buffer-file-name))
980 ;; Construct a (unique) buffer name to correspond.
981 (let ((buf (create-file-buffer (downcase buffer-file-name))))
982 (setq buffer-new-name (buffer-name buf))
983 (kill-buffer buf))
984 (rename-buffer buffer-new-name)))
985 ;; If buffer has no file name, ask user for one.
986 (or buffer-file-name
987 (progn
988 (setq buffer-file-name
989 (expand-file-name (read-file-name "File to save in: ") nil)
990 default-directory (file-name-directory buffer-file-name))
991 (auto-save-mode auto-save-default)))
992 (or (verify-visited-file-modtime (current-buffer))
993 (not (file-exists-p buffer-file-name))
994 (yes-or-no-p
995 (format "%s has changed since visited or saved. Save anyway? "
996 (file-name-nondirectory buffer-file-name)))
997 (error "Save not confirmed"))
998 (save-restriction
999 (widen)
1000 (and (> (point-max) 1)
1001 (/= (char-after (1- (point-max))) ?\n)
1002 (or (eq require-final-newline t)
1003 (and require-final-newline
1004 (y-or-n-p
1005 (format "Buffer %s does not end in newline. Add one? "
1006 (buffer-name)))))
1007 (save-excursion
1008 (goto-char (point-max))
1009 (insert ?\n)))
8c0e7b73 1010 (let ((hooks (append write-contents-hooks write-file-hooks))
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1011 (done nil))
1012 (while (and hooks
1013 (not (setq done (funcall (car hooks)))))
1014 (setq hooks (cdr hooks)))
1015 ;; If a hook returned t, file is already "written".
1016 (cond ((not done)
1017 (if (not (file-writable-p buffer-file-name))
1018 (let ((dir (file-name-directory buffer-file-name)))
1019 (if (not (file-directory-p dir))
1020 (error "%s is not a directory" dir)
1021 (if (not (file-exists-p buffer-file-name))
1022 (error "Directory %s write-protected" dir)
1023 (if (yes-or-no-p
1024 (format "File %s is write-protected; try to save anyway? "
1025 (file-name-nondirectory
1026 buffer-file-name)))
1027 (setq tempsetmodes t)
1028 (error "Attempt to save to a file which you aren't allowed to write"))))))
1029 (or buffer-backed-up
1030 (setq setmodes (backup-buffer)))
1031 (if file-precious-flag
1032 ;; If file is precious, rename it away before
1033 ;; overwriting it.
1034 (let ((rename t)
1035 realname tempname temp)
1036 ;; Chase symlinks; rename the ultimate actual file.
1037 (setq realname buffer-file-name)
1038 (while (setq temp (file-symlink-p realname))
1039 (setq realname temp))
1040 (setq tempname (concat realname "#"))
1041 (condition-case ()
1042 (progn (rename-file realname tempname t)
1043 (setq setmodes (file-modes tempname)))
1044 (file-error (setq rename nil tempname nil)))
1045 (if (file-directory-p realname)
1046 (error "%s is a directory" realname))
1047 (unwind-protect
1048 (progn (clear-visited-file-modtime)
1049 (write-region (point-min) (point-max)
1050 realname nil t)
1051 (setq rename nil))
1052 ;; If rename is still t, writing failed.
1053 ;; So rename the old file back to original name,
1054 (if rename
1055 (progn
1056 (rename-file tempname realname t)
1057 (clear-visited-file-modtime))
1058 ;; Otherwise we don't need the original file,
1059 ;; so flush it, if we still have it.
1060 ;; If rename failed due to name length restriction
1061 ;; then TEMPNAME is now nil.
1062 (if tempname
1063 (condition-case ()
1064 (delete-file tempname)
1065 (error nil))))))
1066 ;; If file not writable, see if we can make it writable
1067 ;; temporarily while we write it.
1068 ;; But no need to do so if we have just backed it up
1069 ;; (setmodes is set) because that says we're superseding.
1070 (cond ((and tempsetmodes (not setmodes))
1071 ;; Change the mode back, after writing.
1072 (setq setmodes (file-modes buffer-file-name))
1073 (set-file-modes buffer-file-name 511)))
1074 (write-region (point-min) (point-max)
1075 buffer-file-name nil t)))))
1076 (if setmodes
1077 (condition-case ()
1078 (set-file-modes buffer-file-name setmodes)
1079 (error nil))))
1080 ;; If the auto-save file was recent before this command,
1081 ;; delete it now.
1082 (delete-auto-save-file-if-necessary recent-save)
1083 (run-hooks 'after-save-hooks))
1084 (message "(No changes need to be saved)")))
1085
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1086(defun save-some-buffers (&optional arg exiting)
1087 "Save some modified file-visiting buffers. Asks user about each one.
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1088Optional argument (the prefix) non-nil means save all with no questions.
1089Optional second argument EXITING means ask about certain non-file buffers
1090 as well as about file buffers."
b4da00e9 1091 (interactive "P")
907482b9 1092 (save-window-excursion
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1093 (if (zerop (map-y-or-n-p
1094 (function
1095 (lambda (buffer)
1096 (and (buffer-modified-p buffer)
1097 (or
1098 (buffer-file-name buffer)
1099 (and exiting
1100 (progn
1101 (set-buffer buffer)
1102 (and buffer-offer-save (> (buffer-size) 0)))))
1103 (if arg
1104 t
1105 (if (buffer-file-name buffer)
1106 (format "Save file %s? "
1107 (buffer-file-name buffer))
1108 (format "Save buffer %s? "
1109 (buffer-name buffer)))))))
1110 (function
1111 (lambda (buffer)
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1112 (set-buffer buffer)
1113 (save-buffer)))
b5e86cb3 1114 (buffer-list)
907482b9 1115 '("buffer" "buffers" "save")
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1116 (list (list ?\C-r (lambda (buf)
1117 (view-buffer buf)
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1118 (setq view-exit-action
1119 '(lambda (ignore)
1120 (exit-recursive-edit)))
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1121 (recursive-edit)
1122 ;; Return nil to ask about BUF again.
1123 nil)
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1124 "display the current buffer"))
1125 ))
b5e86cb3 1126 (message "(No files need saving)"))))
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1127\f
1128(defun not-modified (&optional arg)
1129 "Mark current buffer as unmodified, not needing to be saved.
1130With prefix arg, mark buffer as modified, so \\[save-buffer] will save."
1131 (interactive "P")
1132 (message (if arg "Modification-flag set"
1133 "Modification-flag cleared"))
1134 (set-buffer-modified-p arg))
1135
1136(defun toggle-read-only (&optional arg)
1137 "Change whether this buffer is visiting its file read-only.
1138With arg, set read-only iff arg is positive."
1139 (interactive "P")
1140 (setq buffer-read-only
1141 (if (null arg)
1142 (not buffer-read-only)
1143 (> (prefix-numeric-value arg) 0)))
1144 ;; Force mode-line redisplay
1145 (set-buffer-modified-p (buffer-modified-p)))
1146
1147(defun insert-file (filename)
1148 "Insert contents of file FILENAME into buffer after point.
1149Set mark after the inserted text.
1150
1151This function is meant for the user to run interactively.
1152Don't call it from programs! Use `insert-file-contents' instead.
1153\(Its calling sequence is different; see its documentation)."
1154 (interactive "fInsert file: ")
1155 (let ((tem (insert-file-contents filename)))
1156 (push-mark (+ (point) (car (cdr tem))))))
1157
1158(defun append-to-file (start end filename)
1159 "Append the contents of the region to the end of file FILENAME.
1160When called from a function, expects three arguments,
1161START, END and FILENAME. START and END are buffer positions
1162saying what text to write."
1163 (interactive "r\nFAppend to file: ")
1164 (write-region start end filename t))
1165
1166(defun file-newest-backup (filename)
1167 "Return most recent backup file for FILENAME or nil if no backups exist."
1168 (let* ((filename (expand-file-name filename))
1169 (file (file-name-nondirectory filename))
1170 (dir (file-name-directory filename))
1171 (comp (file-name-all-completions file dir))
1172 newest)
1173 (while comp
1174 (setq file (concat dir (car comp))
1175 comp (cdr comp))
1176 (if (and (backup-file-name-p file)
1177 (or (null newest) (file-newer-than-file-p file newest)))
1178 (setq newest file)))
1179 newest))
1180
1181(defun rename-uniquely ()
1182 "Rename current buffer to a similar name not already taken.
1183This function is useful for creating multiple shell process buffers
1184or multiple mail buffers, etc."
1185 (interactive)
1186 (let* ((new-buf (generate-new-buffer (buffer-name)))
1187 (name (buffer-name new-buf)))
1188 (kill-buffer new-buf)
1189 (rename-buffer name)
1190 (set-buffer-modified-p (buffer-modified-p)))) ; force mode line update
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JB
1191
1192(defun make-directory-path (path)
1193 "Create all the directories along path that don't exist yet."
1194 (interactive "Fdirectory path to create: ")
1195 (let ((path (directory-file-name (expand-file-name path)))
1196 create-list)
1197 (while (not (file-exists-p path))
1198 (setq create-list (cons path create-list)
1199 path (directory-file-name (file-name-directory path))))
1200 (while create-list
1201 (make-directory (car create-list))
1202 (setq create-list (cdr create-list)))))
1203
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RM
1204\f
1205(put 'revert-buffer-function 'permanent-local t)
1206(defvar revert-buffer-function nil
1207 "Function to use to revert this buffer, or nil to do the default.")
1208
1209(put 'revert-buffer-insert-file-contents-function 'permanent-local t)
1210(defvar revert-buffer-insert-file-contents-function nil
1211 "Function to use to insert contents when reverting this buffer.
1212Gets two args, first the nominal file name to use,
1213and second, t if reading the auto-save file.")
1214
8c0e7b73 1215(defun revert-buffer (&optional check-auto noconfirm)
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RM
1216 "Replace the buffer text with the text of the visited file on disk.
1217This undoes all changes since the file was visited or saved.
8c0e7b73
JB
1218With a prefix argument, offer to revert from latest auto-save file, if
1219that is more recent than the visited file.
1220When called from lisp, this is the first argument, CHECK-AUTO; it is optional.
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RM
1221Optional second argument NOCONFIRM means don't ask for confirmation at all.
1222
8c0e7b73
JB
1223If the value of `revert-buffer-function' is non-nil, it is called to
1224do the work."
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RM
1225 (interactive "P")
1226 (if revert-buffer-function
8c0e7b73 1227 (funcall revert-buffer-function (not check-auto) noconfirm)
b4da00e9 1228 (let* ((opoint (point))
8c0e7b73 1229 (auto-save-p (and check-auto (recent-auto-save-p)
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RM
1230 buffer-auto-save-file-name
1231 (file-readable-p buffer-auto-save-file-name)
1232 (y-or-n-p
1233 "Buffer has been auto-saved recently. Revert from auto-save file? ")))
1234 (file-name (if auto-save-p
1235 buffer-auto-save-file-name
1236 buffer-file-name)))
1237 (cond ((null file-name)
1238 (error "Buffer does not seem to be associated with any file"))
1239 ((or noconfirm
1240 (yes-or-no-p (format "Revert buffer from file %s? "
1241 file-name)))
1242 ;; If file was backed up but has changed since,
1243 ;; we shd make another backup.
1244 (and (not auto-save-p)
5bbbceb1 1245 (not (verify-visited-file-modtime (current-buffer)))
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RM
1246 (setq buffer-backed-up nil))
1247 ;; Get rid of all undo records for this buffer.
1248 (or (eq buffer-undo-list t)
1249 (setq buffer-undo-list nil))
1250 (let ((buffer-read-only nil)
1251 ;; Don't make undo records for the reversion.
1252 (buffer-undo-list t))
1253 (if revert-buffer-insert-file-contents-function
1254 (funcall revert-buffer-insert-file-contents-function
1255 file-name auto-save-p)
1256 (if (not (file-exists-p file-name))
1257 (error "File %s no longer exists!" file-name))
1258 ;; Bind buffer-file-name to nil
1259 ;; so that we don't try to lock the file.
1260 (let ((buffer-file-name nil))
1261 (or auto-save-p
1262 (unlock-buffer))
1263 (erase-buffer))
1264 (insert-file-contents file-name (not auto-save-p))))
1265 (goto-char (min opoint (point-max)))
1266 (after-find-file nil)
1267 t)))))
1268
1269(defun recover-file (file)
1270 "Visit file FILE, but get contents from its last auto-save file."
1271 (interactive
1272 (let ((prompt-file buffer-file-name)
1273 (file-name nil)
1274 (file-dir nil))
1275 (and prompt-file
1276 (setq file-name (file-name-nondirectory prompt-file)
1277 file-dir (file-name-directory prompt-file)))
1278 (list (read-file-name "Recover file: "
1279 file-dir nil nil file-name))))
1280 (setq file (expand-file-name file))
1281 (if (auto-save-file-name-p file) (error "%s is an auto-save file" file))
1282 (let ((file-name (let ((buffer-file-name file))
1283 (make-auto-save-file-name))))
1284 (cond ((not (file-newer-than-file-p file-name file))
1285 (error "Auto-save file %s not current" file-name))
1286 ((save-window-excursion
1287 (if (not (eq system-type 'vax-vms))
1288 (with-output-to-temp-buffer "*Directory*"
1289 (buffer-disable-undo standard-output)
1290 (call-process "ls" nil standard-output nil
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1291 (if (file-symlink-p file) "-lL" "-l")
1292 file file-name)))
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1293 (yes-or-no-p (format "Recover auto save file %s? " file-name)))
1294 (switch-to-buffer (find-file-noselect file t))
1295 (let ((buffer-read-only nil))
1296 (erase-buffer)
1297 (insert-file-contents file-name nil))
1298 (after-find-file nil))
1299 (t (error "Recover-file cancelled.")))))
1300
1301(defun kill-some-buffers ()
1302 "For each buffer, ask whether to kill it."
1303 (interactive)
1304 (let ((list (buffer-list)))
1305 (while list
1306 (let* ((buffer (car list))
1307 (name (buffer-name buffer)))
1308 (and (not (string-equal name ""))
1309 (/= (aref name 0) ? )
1310 (yes-or-no-p
1311 (format "Buffer %s %s. Kill? "
1312 name
1313 (if (buffer-modified-p buffer)
1314 "HAS BEEN EDITED" "is unmodified")))
1315 (kill-buffer buffer)))
1316 (setq list (cdr list)))))
1317\f
1318(defun auto-save-mode (arg)
1319 "Toggle auto-saving of contents of current buffer.
1320With ARG, turn auto-saving on if positive, else off."
1321 (interactive "P")
1322 (setq buffer-auto-save-file-name
1323 (and (if (null arg)
1324 (not buffer-auto-save-file-name)
1325 (or (eq arg t) (listp arg) (and (integerp arg) (> arg 0))))
1326 (if (and buffer-file-name auto-save-visited-file-name
1327 (not buffer-read-only))
1328 buffer-file-name
1329 (make-auto-save-file-name))))
1330 (if (interactive-p)
1331 (message "Auto-save %s (in this buffer)"
1332 (if buffer-auto-save-file-name "on" "off")))
1333 buffer-auto-save-file-name)
1334
1335(defun rename-auto-save-file ()
1336 "Adjust current buffer's auto save file name for current conditions.
1337Also rename any existing auto save file, if it was made in this session."
1338 (let ((osave buffer-auto-save-file-name))
1339 (setq buffer-auto-save-file-name
1340 (make-auto-save-file-name))
1341 (if (and osave buffer-auto-save-file-name
1342 (not (string= buffer-auto-save-file-name buffer-file-name))
1343 (not (string= buffer-auto-save-file-name osave))
1344 (file-exists-p osave)
1345 (recent-auto-save-p))
1346 (rename-file osave buffer-auto-save-file-name t))))
1347
1348(defun make-auto-save-file-name ()
1349 "Return file name to use for auto-saves of current buffer.
1350Does not consider `auto-save-visited-file-name' as that variable is checked
1351before calling this function. You can redefine this for customization.
1352See also `auto-save-file-name-p'."
1353 (if buffer-file-name
1354 (concat (file-name-directory buffer-file-name)
1355 "#"
1356 (file-name-nondirectory buffer-file-name)
1357 "#")
1358 ;; For non-file bfr, use bfr name and Emacs pid.
1359 (expand-file-name (format "#%s#%s#" (buffer-name) (make-temp-name "")))))
1360
1361(defun auto-save-file-name-p (filename)
1362 "Return non-nil if FILENAME can be yielded by `make-auto-save-file-name'.
1363FILENAME should lack slashes. You can redefine this for customization."
1364 (string-match "^#.*#$" filename))
1365\f
1366(defconst list-directory-brief-switches
1367 (if (eq system-type 'vax-vms) "" "-CF")
1368 "*Switches for list-directory to pass to `ls' for brief listing,")
1369
1370(defconst list-directory-verbose-switches
1371 (if (eq system-type 'vax-vms)
1372 "/PROTECTION/SIZE/DATE/OWNER/WIDTH=(OWNER:10)"
1373 "-l")
1374 "*Switches for list-directory to pass to `ls' for verbose listing,")
1375
1376(defun list-directory (dirname &optional verbose)
1377 "Display a list of files in or matching DIRNAME, a la `ls'.
1378DIRNAME is globbed by the shell if necessary.
1379Prefix arg (second arg if noninteractive) means supply -l switch to `ls'.
1380Actions controlled by variables `list-directory-brief-switches'
1381and `list-directory-verbose-switches'."
1382 (interactive (let ((pfx current-prefix-arg))
1383 (list (read-file-name (if pfx "List directory (verbose): "
1384 "List directory (brief): ")
1385 nil default-directory nil)
1386 pfx)))
1387 (let ((switches (if verbose list-directory-verbose-switches
1388 list-directory-brief-switches)))
1389 (or dirname (setq dirname default-directory))
1390 (setq dirname (expand-file-name dirname))
1391 (with-output-to-temp-buffer "*Directory*"
1392 (buffer-disable-undo standard-output)
1393 (princ "Directory ")
1394 (princ dirname)
1395 (terpri)
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1396 (save-excursion
1397 (set-buffer "*Directory*")
1398 (let ((wildcard (not (file-directory-p dirname))))
1399 (insert-directory dirname switches wildcard (not wildcard)))))))
1400
1401(defvar insert-directory-program "ls"
1402 "Absolute or relative name of the `ls' program used by `insert-directory'.")
1403
1404;; insert-directory
1405;; - must insert _exactly_one_line_ describing FILE if WILDCARD and
1406;; FULL-DIRECTORY-P is nil.
1407;; The single line of output must display FILE's name as it was
1408;; given, namely, an absolute path name.
1409;; - must insert exactly one line for each file if WILDCARD or
1410;; FULL-DIRECTORY-P is t, plus one optional "total" line
1411;; before the file lines, plus optional text after the file lines.
1412;; Lines are delimited by "\n", so filenames containing "\n" are not
1413;; allowed.
1414;; File lines should display the basename.
1415;; - must be consistent with
1416;; - functions dired-move-to-filename, (these two define what a file line is)
1417;; dired-move-to-end-of-filename,
1418;; dired-between-files, (shortcut for (not (dired-move-to-filename)))
1419;; dired-insert-headerline
1420;; dired-after-subdir-garbage (defines what a "total" line is)
1421;; - variable dired-subdir-regexp
1422(defun insert-directory (file switches &optional wildcard full-directory-p)
1423 "Insert directory listing for of FILE, formatted according to SWITCHES.
1424Leaves point after the inserted text.
1425Optional third arg WILDCARD means treat FILE as shell wildcard.
1426Optional fourth arg FULL-DIRECTORY-P means file is a directory and
1427switches do not contain `d', so that a full listing is expected.
1428
1429This works by running a directory listing program
1430whose name is in the variable `ls-program'.
1431If WILDCARD, it also runs the shell specified by `shell-file-name'."
1432 (let (handler (handlers file-name-handler-alist))
1433 (while (and (consp handlers) (null handler))
1434 (if (and (consp (car handlers))
1435 (stringp (car (car handlers)))
1436 (string-match (car (car handlers)) file))
1437 (setq handler (cdr (car handlers))))
1438 (setq handlers (cdr handlers)))
1439 (if handler
1440 (funcall handler 'insert-directory file switches
1441 wildcard full-directory-p)
b4da00e9 1442 (if (eq system-type 'vax-vms)
c3554e95
RS
1443 (vms-read-directory file switches (current-buffer))
1444 (if wildcard
1445 (let ((default-directory (file-name-directory file)))
1446 (call-process shell-file-name nil t nil
1447 "-c" (concat insert-directory-program
1448 " -d " switches " "
1449 (file-name-nondirectory file))))
1450 (call-process insert-directory-program nil t nil switches file))))))
b4da00e9
RM
1451
1452(defun save-buffers-kill-emacs (&optional arg)
1453 "Offer to save each buffer, then kill this Emacs process.
1454With prefix arg, silently save all file-visiting buffers, then kill."
1455 (interactive "P")
1456 (save-some-buffers arg t)
1457 (and (or (not (memq t (mapcar (function
1458 (lambda (buf) (and (buffer-file-name buf)
1459 (buffer-modified-p buf))))
1460 (buffer-list))))
1461 (yes-or-no-p "Modified buffers exist; exit anyway? "))
1462 (or (not (fboundp 'process-list))
1463 ;; process-list is not defined on VMS.
1464 (let ((processes (process-list))
1465 active)
1466 (while processes
528415e7 1467 (and (memq (process-status (car processes)) '(run stop open))
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RM
1468 (let ((val (process-kill-without-query (car processes))))
1469 (process-kill-without-query (car processes) val)
1470 val)
1471 (setq active t))
1472 (setq processes (cdr processes)))
1473 (or (not active)
1474 (yes-or-no-p "Active processes exist; kill them and exit anyway? "))))
1475 (kill-emacs)))
1476\f
1477(define-key ctl-x-map "\C-f" 'find-file)
1478(define-key ctl-x-map "\C-q" 'toggle-read-only)
1479(define-key ctl-x-map "\C-r" 'find-file-read-only)
1480(define-key ctl-x-map "\C-v" 'find-alternate-file)
1481(define-key ctl-x-map "\C-s" 'save-buffer)
1482(define-key ctl-x-map "s" 'save-some-buffers)
1483(define-key ctl-x-map "\C-w" 'write-file)
1484(define-key ctl-x-map "i" 'insert-file)
1485(define-key esc-map "~" 'not-modified)
1486(define-key ctl-x-map "\C-d" 'list-directory)
1487(define-key ctl-x-map "\C-c" 'save-buffers-kill-emacs)
1488
1489(define-key ctl-x-4-map "f" 'find-file-other-window)
1490(define-key ctl-x-4-map "r" 'find-file-read-only-other-window)
1491(define-key ctl-x-4-map "\C-f" 'find-file-other-window)
1492(define-key ctl-x-4-map "b" 'switch-to-buffer-other-window)
924f0a24 1493(define-key ctl-x-4-map "\C-o" 'display-buffer)
5bbbceb1 1494
f98955ea
JB
1495(define-key ctl-x-5-map "b" 'switch-to-buffer-other-frame)
1496(define-key ctl-x-5-map "f" 'find-file-other-frame)
1497(define-key ctl-x-5-map "\C-f" 'find-file-other-frame)
1498(define-key ctl-x-5-map "r" 'find-file-read-only-other-frame)
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1499
1500;;; files.el ends here