(pages-copy-header-and-position): Call end-of-line, not forward-line.
[bpt/emacs.git] / lisp / files.el
1 ;;; files.el --- file input and output commands for Emacs
2
3 ;; Copyright (C) 1985, 1986, 1987, 1992, 1993 Free Software Foundation, Inc.
4
5 ;; Maintainer: FSF
6
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
11 ;; the Free Software Foundation; either version 2, or (at your option)
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
23 ;;; Commentary:
24
25 ;; Defines most of Emacs's file- and directory-handling functions,
26 ;; including basic file visiting, backup generation, link handling,
27 ;; ITS-id version control, load- and write-hook handling, and the like.
28
29 ;;; Code:
30
31 (defconst delete-auto-save-files t
32 "*Non-nil means delete a buffer's auto-save file when the buffer is saved.")
33
34 (defconst directory-abbrev-alist
35 nil
36 "*Alist of abbreviations for file directories.
37 A list of elements of the form (FROM . TO), each meaning to replace
38 FROM with TO when it appears in a directory name. This replacement is
39 done when setting up the default directory of a newly visited file.
40 *Every* FROM string should start with `^'.
41
42 Do not use `~' in the TO strings.
43 They should be ordinary absolute directory names.
44
45 Use this feature when you have directories which you normally refer to
46 via absolute symbolic links. Make TO the name of the link, and FROM
47 the name it is linked to.")
48
49 ;;; Turn off backup files on VMS since it has version numbers.
50 (defconst make-backup-files (not (eq system-type 'vax-vms))
51 "*Non-nil means make a backup of a file the first time it is saved.
52 This can be done by renaming the file or by copying.
53
54 Renaming means that Emacs renames the existing file so that it is a
55 backup file, then writes the buffer into a new file. Any other names
56 that the old file had will now refer to the backup file. The new file
57 is owned by you and its group is defaulted.
58
59 Copying means that Emacs copies the existing file into the backup
60 file, then writes the buffer on top of the existing file. Any other
61 names that the old file had will now refer to the new (edited) file.
62 The file's owner and group are unchanged.
63
64 The choice of renaming or copying is controlled by the variables
65 `backup-by-copying', `backup-by-copying-when-linked' and
66 `backup-by-copying-when-mismatch'. See also `backup-inhibited'.")
67
68 ;; Do this so that local variables based on the file name
69 ;; are not overridden by the major mode.
70 (defvar backup-inhibited nil
71 "Non-nil means don't make a backup, regardless of the other parameters.
72 This variable is intended for use by making it local to a buffer.
73 But it is local only if you make it local.")
74 (put 'backup-inhibited 'permanent-local t)
75
76 (defconst backup-by-copying nil
77 "*Non-nil means always use copying to create backup files.
78 See documentation of variable `make-backup-files'.")
79
80 (defconst backup-by-copying-when-linked nil
81 "*Non-nil means use copying to create backups for files with multiple names.
82 This causes the alternate names to refer to the latest version as edited.
83 This variable is relevant only if `backup-by-copying' is nil.")
84
85 (defconst backup-by-copying-when-mismatch nil
86 "*Non-nil means create backups by copying if this preserves owner or group.
87 Renaming may still be used (subject to control of other variables)
88 when it would not result in changing the owner or group of the file;
89 that is, for files which are owned by you and whose group matches
90 the default for a new file created there by you.
91 This variable is relevant only if `backup-by-copying' is nil.")
92
93 (defvar backup-enable-predicate
94 '(lambda (name)
95 (or (< (length name) 5)
96 (not (string-equal "/tmp/" (substring name 0 5)))))
97 "Predicate that looks at a file name and decides whether to make backups.
98 Called with an absolute file name as argument, it returns t to enable backup.")
99
100 (defconst buffer-offer-save nil
101 "*Non-nil in a buffer means offer to save the buffer on exit
102 even if the buffer is not visiting a file.
103 Automatically local in all buffers.")
104 (make-variable-buffer-local 'buffer-offer-save)
105
106 (defconst find-file-existing-other-name nil
107 "*Non-nil means find a file under alternative names, in existing buffers.
108 This means if any existing buffer is visiting the file you want
109 under another name, you get the existing buffer instead of a new buffer.")
110
111 (defconst find-file-visit-truename nil
112 "*Non-nil means visit a file under its truename.
113 The truename of a file is found by chasing all links
114 both at the file level and at the levels of the containing directories.")
115
116 (defvar buffer-file-truename nil
117 "The truename of the file visited in the current buffer.
118 This variable is automatically local in all buffers, when non-nil.")
119 (make-variable-buffer-local 'buffer-file-truename)
120 (put 'buffer-file-truename 'permanent-local t)
121
122 (defvar buffer-file-number nil
123 "The device number and file number of the file visited in the current buffer.
124 The value is a list of the form (FILENUM DEVNUM).
125 This pair of numbers uniquely identifies the file.
126 If the buffer is visiting a new file, the value is nil.")
127 (make-variable-buffer-local 'buffer-file-number)
128 (put 'buffer-file-number 'permanent-local t)
129
130 (defconst file-precious-flag nil
131 "*Non-nil means protect against I/O errors while saving files.
132 Some modes set this non-nil in particular buffers.")
133
134 (defvar version-control nil
135 "*Control use of version numbers for backup files.
136 t means make numeric backup versions unconditionally.
137 nil means make them for files that have some already.
138 never means do not make them.")
139
140 (defvar dired-kept-versions 2
141 "*When cleaning directory, number of versions to keep.")
142
143 (defvar trim-versions-without-asking nil
144 "*If t, deletes excess backup versions silently.
145 If nil, asks confirmation. Any other value prevents any trimming.")
146
147 (defvar kept-old-versions 2
148 "*Number of oldest versions to keep when a new numbered backup is made.")
149
150 (defvar kept-new-versions 2
151 "*Number of newest versions to keep when a new numbered backup is made.
152 Includes the new backup. Must be > 0")
153
154 (defconst require-final-newline nil
155 "*Value of t says silently ensure a file ends in a newline when it is saved.
156 Non-nil but not t says ask user whether to add a newline when there isn't one.
157 nil means don't add newlines.")
158
159 (defconst auto-save-default t
160 "*Non-nil says by default do auto-saving of every file-visiting buffer.")
161
162 (defconst auto-save-visited-file-name nil
163 "*Non-nil says auto-save a buffer in the file it is visiting, when practical.
164 Normally auto-save files are written under other names.")
165
166 (defconst save-abbrevs nil
167 "*Non-nil means save word abbrevs too when files are saved.
168 Loading an abbrev file sets this to t.")
169
170 (defconst find-file-run-dired t
171 "*Non-nil says run dired if `find-file' is given the name of a directory.")
172
173 ;;;It is not useful to make this a local variable.
174 ;;;(put 'find-file-not-found-hooks 'permanent-local t)
175 (defvar find-file-not-found-hooks nil
176 "List of functions to be called for `find-file' on nonexistent file.
177 These functions are called as soon as the error is detected.
178 `buffer-file-name' is already set up.
179 The functions are called in the order given until one of them returns non-nil.")
180
181 ;;;It is not useful to make this a local variable.
182 ;;;(put 'find-file-hooks 'permanent-local t)
183 (defvar find-file-hooks nil
184 "List of functions to be called after a buffer is loaded from a file.
185 The buffer's local variables (if any) will have been processed before the
186 functions are called.")
187
188 (defvar write-file-hooks nil
189 "List of functions to be called before writing out a buffer to a file.
190 If one of them returns non-nil, the file is considered already written
191 and the rest are not called.
192 These hooks are considered to pertain to the visited file.
193 So this list is cleared if you change the visited file name.
194 See also `write-contents-hooks'.
195 Don't make this variable buffer-local; instead, use `local-write-file-hooks'.")
196 ;;; However, in case someone does make it local...
197 (put 'write-file-hooks 'permanent-local t)
198
199 (defvar local-write-file-hooks nil
200 "Just like `write-file-hooks', except intended for per-buffer use.
201 The functions in this list are called before the ones in
202 `write-file-hooks'.")
203 (make-variable-buffer-local 'local-write-file-hooks)
204 (put 'local-write-file-hooks 'permanent-local t)
205
206 (defvar write-contents-hooks nil
207 "List of functions to be called before writing out a buffer to a file.
208 If one of them returns non-nil, the file is considered already written
209 and the rest are not called.
210 These hooks are considered to pertain to the buffer's contents,
211 not to the particular visited file; thus, `set-visited-file-name' does
212 not clear this variable, but changing the major mode does clear it.
213 See also `write-file-hooks'.")
214
215 (defconst enable-local-variables t
216 "*Control use of local-variables lists in files you visit.
217 The value can be t, nil or something else.
218 A value of t means local-variables lists are obeyed;
219 nil means they are ignored; anything else means query.
220
221 The command \\[normal-mode] always obeys local-variables lists
222 and ignores this variable.")
223
224 (defconst enable-local-eval 'maybe
225 "*Control processing of the \"variable\" `eval' in a file's local variables.
226 The value can be t, nil or something else.
227 A value of t means obey `eval' variables;
228 nil means ignore them; anything else means query.
229
230 The command \\[normal-mode] always obeys local-variables lists
231 and ignores this variable.")
232
233 ;; Avoid losing in versions where CLASH_DETECTION is disabled.
234 (or (fboundp 'lock-buffer)
235 (defalias 'lock-buffer 'ignore))
236 (or (fboundp 'unlock-buffer)
237 (defalias 'unlock-buffer 'ignore))
238
239 ;; This hook function provides support for ange-ftp host name
240 ;; completion. It runs the usual ange-ftp hook, but only for
241 ;; completion operations. Having this here avoids the need
242 ;; to load ange-ftp when it's not really in use.
243 (defun ange-ftp-completion-hook-function (op &rest args)
244 (if (memq op '(file-name-completion file-name-all-completions))
245 (apply 'ange-ftp-hook-function op args)
246 (let (file-name-handler-alist)
247 (apply op args))))
248 \f
249 (defun pwd ()
250 "Show the current default directory."
251 (interactive nil)
252 (message "Directory %s" default-directory))
253
254 (defvar cd-path nil
255 "Value of the CDPATH environment variable, as a list.
256 Not actually set up until the first time you you use it.")
257
258 (defun parse-colon-path (cd-path)
259 "Explode a colon-separated list of paths into a string list."
260 (and cd-path
261 (let (cd-prefix cd-list (cd-start 0) cd-colon)
262 (setq cd-path (concat cd-path ":"))
263 (while (setq cd-colon (string-match ":" cd-path cd-start))
264 (setq cd-list
265 (nconc cd-list
266 (list (if (= cd-start cd-colon)
267 nil
268 (substitute-in-file-name
269 (file-name-as-directory
270 (substring cd-path cd-start cd-colon)))))))
271 (setq cd-start (+ cd-colon 1)))
272 cd-list)))
273
274 (defun cd-absolute (dir)
275 "Change current directory to given absolute file name DIR."
276 (setq dir (abbreviate-file-name (expand-file-name dir)))
277 (if (not (eq system-type 'vax-vms))
278 (setq dir (file-name-as-directory dir)))
279 (if (not (file-directory-p dir))
280 (error "%s is not a directory" dir)
281 (if (file-executable-p dir)
282 (setq default-directory dir)
283 (error "Cannot cd to %s: Permission denied" dir))))
284
285 (defun cd (dir)
286 "Make DIR become the current buffer's default directory.
287 If your environment includes a `CDPATH' variable, try each one of that
288 colon-separated list of directories when resolving a relative directory name."
289 (interactive "FChange default directory: ")
290 (if (file-name-absolute-p dir)
291 (cd-absolute (expand-file-name dir))
292 (if (null cd-path)
293 (let ((trypath (parse-colon-path (getenv "CDPATH"))))
294 (setq cd-path (or trypath (list "./")))))
295 (if (not (catch 'found
296 (mapcar
297 (function (lambda (x)
298 (let ((f (expand-file-name (concat x dir))))
299 (if (file-directory-p f)
300 (progn
301 (cd-absolute f)
302 (throw 'found t))))))
303 cd-path)
304 nil))
305 (error "No such directory found via CDPATH environment variable"))))
306
307 (defun load-file (file)
308 "Load the Lisp file named FILE."
309 (interactive "fLoad file: ")
310 (load (expand-file-name file) nil nil t))
311
312 (defun load-library (library)
313 "Load the library named LIBRARY.
314 This is an interface to the function `load'."
315 (interactive "sLoad library: ")
316 (load library))
317
318 ;; OTHER is the other file to be compared.
319 (defun file-local-copy (file)
320 "Copy the file FILE into a temporary file on this machine.
321 Returns the name of the local copy, or nil, if FILE is directly
322 accessible."
323 (let ((handler (find-file-name-handler file)))
324 (if handler
325 (funcall handler 'file-local-copy file)
326 nil)))
327
328 (defun file-truename (filename)
329 "Return the truename of FILENAME, which should be absolute.
330 The truename of a file name is found by chasing symbolic links
331 both at the level of the file and at the level of the directories
332 containing it, until no links are left at any level."
333 (if (or (string= filename "~")
334 (and (string= (substring filename 0 1) "~")
335 (string-match "~[^/]*" filename)))
336 (progn
337 (setq filename (expand-file-name filename))
338 (if (string= filename "")
339 (setq filename "/"))))
340 (let ((handler (find-file-name-handler filename)))
341 ;; For file name that has a special handler, call handler.
342 ;; This is so that ange-ftp can save time by doing a no-op.
343 (if handler
344 (funcall handler 'file-truename filename)
345 (let ((dir (file-name-directory filename))
346 target dirfile)
347 ;; Get the truename of the directory.
348 (setq dirfile (directory-file-name dir))
349 ;; If these are equal, we have the (or a) root directory.
350 (or (string= dir dirfile)
351 (setq dir (file-name-as-directory (file-truename dirfile))))
352 (if (equal ".." (file-name-nondirectory filename))
353 (directory-file-name (file-name-directory (directory-file-name dir)))
354 (if (equal "." (file-name-nondirectory filename))
355 (directory-file-name dir)
356 ;; Put it back on the file name.
357 (setq filename (concat dir (file-name-nondirectory filename)))
358 ;; Is the file name the name of a link?
359 (setq target (file-symlink-p filename))
360 (if target
361 ;; Yes => chase that link, then start all over
362 ;; since the link may point to a directory name that uses links.
363 ;; We can't safely use expand-file-name here
364 ;; since target might look like foo/../bar where foo
365 ;; is itself a link. Instead, we handle . and .. above.
366 (if (file-name-absolute-p target)
367 (file-truename target)
368 (file-truename (concat dir target)))
369 ;; No, we are done!
370 filename)))))))
371
372 (defun file-chase-links (filename)
373 "Chase links in FILENAME until a name that is not a link.
374 Does not examine containing directories for links,
375 unlike `file-truename'."
376 (let (tem (count 100) (newname filename))
377 (while (setq tem (file-symlink-p newname))
378 (if (= count 0)
379 (error "Apparent cycle of symbolic links for %s" filename))
380 ;; Handle `..' by hand, since it needs to work in the
381 ;; target of any directory symlink.
382 ;; This code is not quite complete; it does not handle
383 ;; embedded .. in some cases such as ./../foo and foo/bar/../../../lose.
384 (while (string-match "\\.\\./" tem)
385 (setq tem (substring tem 3))
386 (setq newname (file-name-as-directory
387 ;; Do the .. by hand.
388 (directory-file-name
389 (file-name-directory
390 ;; Chase links in the default dir of the symlink.
391 (file-chase-links
392 (directory-file-name
393 (file-name-directory newname))))))))
394 (setq newname (expand-file-name tem (file-name-directory newname)))
395 (setq count (1- count)))
396 newname))
397 \f
398 (defun switch-to-buffer-other-window (buffer)
399 "Select buffer BUFFER in another window."
400 (interactive "BSwitch to buffer in other window: ")
401 (let ((pop-up-windows t))
402 (pop-to-buffer buffer t)))
403
404 (defun switch-to-buffer-other-frame (buffer)
405 "Switch to buffer BUFFER in another frame."
406 (interactive "BSwitch to buffer in other frame: ")
407 (let ((pop-up-frames t))
408 (pop-to-buffer buffer t)))
409
410 (defun find-file (filename)
411 "Edit file FILENAME.
412 Switch to a buffer visiting file FILENAME,
413 creating one if none already exists."
414 (interactive "FFind file: ")
415 (switch-to-buffer (find-file-noselect filename)))
416
417 (defun find-file-other-window (filename)
418 "Edit file FILENAME, in another window.
419 May create a new window, or reuse an existing one.
420 See the function `display-buffer'."
421 (interactive "FFind file in other window: ")
422 (switch-to-buffer-other-window (find-file-noselect filename)))
423
424 (defun find-file-other-frame (filename)
425 "Edit file FILENAME, in another frame.
426 May create a new frame, or reuse an existing one.
427 See the function `display-buffer'."
428 (interactive "FFind file in other frame: ")
429 (switch-to-buffer-other-frame (find-file-noselect filename)))
430
431 (defun find-file-read-only (filename)
432 "Edit file FILENAME but don't allow changes.
433 Like \\[find-file] but marks buffer as read-only.
434 Use \\[toggle-read-only] to permit editing."
435 (interactive "fFind file read-only: ")
436 (find-file filename)
437 (setq buffer-read-only t)
438 (current-buffer))
439
440 (defun find-file-read-only-other-window (filename)
441 "Edit file FILENAME in another window but don't allow changes.
442 Like \\[find-file-other-window] but marks buffer as read-only.
443 Use \\[toggle-read-only] to permit editing."
444 (interactive "fFind file read-only other window: ")
445 (find-file-other-window filename)
446 (setq buffer-read-only t)
447 (current-buffer))
448
449 (defun find-file-read-only-other-frame (filename)
450 "Edit file FILENAME in another frame but don't allow changes.
451 Like \\[find-file-other-frame] but marks buffer as read-only.
452 Use \\[toggle-read-only] to permit editing."
453 (interactive "fFind file read-only other frame: ")
454 (find-file-other-frame filename)
455 (setq buffer-read-only t)
456 (current-buffer))
457
458 (defun find-alternate-file (filename)
459 "Find file FILENAME, select its buffer, kill previous buffer.
460 If the current buffer now contains an empty file that you just visited
461 \(presumably by mistake), use this command to visit the file you really want."
462 (interactive
463 (let ((file buffer-file-name)
464 (file-name nil)
465 (file-dir nil))
466 (and file
467 (setq file-name (file-name-nondirectory file)
468 file-dir (file-name-directory file)))
469 (list (read-file-name
470 "Find alternate file: " file-dir nil nil file-name))))
471 (and (buffer-modified-p)
472 ;; (not buffer-read-only)
473 (not (yes-or-no-p (format "Buffer %s is modified; kill anyway? "
474 (buffer-name))))
475 (error "Aborted"))
476 (let ((obuf (current-buffer))
477 (ofile buffer-file-name)
478 (onum buffer-file-number)
479 (otrue buffer-file-truename)
480 (oname (buffer-name)))
481 (rename-buffer " **lose**")
482 (setq buffer-file-name nil)
483 (setq buffer-file-number nil)
484 (setq buffer-file-truename nil)
485 (unwind-protect
486 (progn
487 (unlock-buffer)
488 (find-file filename))
489 (cond ((eq obuf (current-buffer))
490 (setq buffer-file-name ofile)
491 (setq buffer-file-number onum)
492 (setq buffer-file-truename otrue)
493 (lock-buffer)
494 (rename-buffer oname))))
495 (or (eq (current-buffer) obuf)
496 (kill-buffer obuf))))
497
498 (defun create-file-buffer (filename)
499 "Create a suitably named buffer for visiting FILENAME, and return it.
500 FILENAME (sans directory) is used unchanged if that name is free;
501 otherwise a string <2> or <3> or ... is appended to get an unused name."
502 (let ((lastname (file-name-nondirectory filename)))
503 (if (string= lastname "")
504 (setq lastname filename))
505 (generate-new-buffer lastname)))
506
507 (defun generate-new-buffer (name)
508 "Create and return a buffer with a name based on NAME.
509 Choose the buffer's name using `generate-new-buffer-name'."
510 (get-buffer-create (generate-new-buffer-name name)))
511
512 (defconst automount-dir-prefix "^/tmp_mnt/"
513 "Regexp to match the automounter prefix in a directory name.")
514
515 (defvar abbreviated-home-dir nil
516 "The user's homedir abbreviated according to `directory-abbrev-list'.")
517
518 (defun abbreviate-file-name (filename)
519 "Return a version of FILENAME shortened using `directory-abbrev-alist'.
520 This also substitutes \"~\" for the user's home directory.
521 Type \\[describe-variable] directory-abbrev-alist RET for more information."
522 ;; Get rid of the prefixes added by the automounter.
523 (if (and (string-match automount-dir-prefix filename)
524 (file-exists-p (file-name-directory
525 (substring filename (1- (match-end 0))))))
526 (setq filename (substring filename (1- (match-end 0)))))
527 (let ((tail directory-abbrev-alist))
528 ;; If any elt of directory-abbrev-alist matches this name,
529 ;; abbreviate accordingly.
530 (while tail
531 (if (string-match (car (car tail)) filename)
532 (setq filename
533 (concat (cdr (car tail)) (substring filename (match-end 0)))))
534 (setq tail (cdr tail)))
535 ;; Compute and save the abbreviated homedir name.
536 ;; We defer computing this until the first time it's needed, to
537 ;; give time for directory-abbrev-alist to be set properly.
538 ;; We include a slash at the end, to avoid spurious matches
539 ;; such as `/usr/foobar' when the home dir is `/usr/foo'.
540 (or abbreviated-home-dir
541 (setq abbreviated-home-dir
542 (let ((abbreviated-home-dir "$foo"))
543 (concat "^" (abbreviate-file-name (expand-file-name "~"))
544 "\\(/\\|$\\)"))))
545
546 ;; If FILENAME starts with the abbreviated homedir,
547 ;; make it start with `~' instead.
548 (if (string-match abbreviated-home-dir filename)
549 (setq filename
550 (concat "~"
551 ;; If abbreviated-home-dir ends with a slash,
552 ;; don't remove the corresponding slash from
553 ;; filename. On MS-DOS and OS/2, you can have
554 ;; home directories like "g:/", in which it is
555 ;; important not to remove the slash. And what
556 ;; about poor root on Unix systems?
557 (if (eq ?/ (aref abbreviated-home-dir
558 (1- (length abbreviated-home-dir))))
559 "/"
560 "")
561 (substring filename (match-beginning 1) (match-end 1))
562 (substring filename (match-end 0)))))
563 filename))
564
565 (defvar find-file-not-true-dirname-list nil
566 "*List of logical names for which visiting shouldn't save the true dirname.
567 On VMS, when you visit a file using a logical name that searches a path,
568 you may or may not want the visited file name to record the specific
569 directory where the file was found. If you *do not* want that, add the logical
570 name to this list as a string.")
571
572 (defun find-file-noselect (filename &optional nowarn)
573 "Read file FILENAME into a buffer and return the buffer.
574 If a buffer exists visiting FILENAME, return that one, but
575 verify that the file has not changed since visited or saved.
576 The buffer is not selected, just returned to the caller."
577 (setq filename
578 (abbreviate-file-name
579 (expand-file-name filename)))
580 (if (file-directory-p filename)
581 (if find-file-run-dired
582 (dired-noselect filename)
583 (error "%s is a directory." filename))
584 (let* ((buf (get-file-buffer filename))
585 (truename (abbreviate-file-name (file-truename filename)))
586 (number (nthcdr 10 (file-attributes truename)))
587 ;; Find any buffer for a file which has same truename.
588 (same-truename
589 (or buf ; Shortcut
590 (let (found
591 (list (buffer-list)))
592 (while (and (not found) list)
593 (save-excursion
594 (set-buffer (car list))
595 (if (and buffer-file-name
596 (string= buffer-file-truename truename))
597 (setq found (car list))))
598 (setq list (cdr list)))
599 found)))
600 (same-number
601 (or buf ; Shortcut
602 (and number
603 (let (found
604 (list (buffer-list)))
605 (while (and (not found) list)
606 (save-excursion
607 (set-buffer (car list))
608 (if (and (equal buffer-file-number number)
609 ;; Verify this buffer's file number
610 ;; still belongs to its file.
611 (file-exists-p buffer-file-name)
612 (equal (nthcdr 10 (file-attributes buffer-file-name)) number))
613 (setq found (car list))))
614 (setq list (cdr list)))
615 found))))
616 error)
617 ;; Let user know if there is a buffer with the same truename.
618 (if (and (not buf) same-truename (not nowarn))
619 (message "%s and %s are the same file (%s)"
620 filename (buffer-file-name same-truename)
621 truename)
622 (if (and (not buf) same-number (not nowarn))
623 (message "%s and %s are the same file"
624 filename (buffer-file-name same-number))))
625
626 ;; Optionally also find that buffer.
627 (if (or find-file-existing-other-name find-file-visit-truename)
628 (setq buf (or same-truename same-number)))
629 (if buf
630 (or nowarn
631 (verify-visited-file-modtime buf)
632 (cond ((not (file-exists-p filename))
633 (error "File %s no longer exists!" filename))
634 ((yes-or-no-p
635 (format
636 (if (buffer-modified-p buf)
637 "File %s changed on disk. Discard your edits? "
638 "File %s changed on disk. Read the new version? ")
639 (file-name-nondirectory filename)))
640 (save-excursion
641 (set-buffer buf)
642 (revert-buffer t t)))))
643 (save-excursion
644 ;;; The truename stuff makes this obsolete.
645 ;;; (let* ((link-name (car (file-attributes filename)))
646 ;;; (linked-buf (and (stringp link-name)
647 ;;; (get-file-buffer link-name))))
648 ;;; (if (bufferp linked-buf)
649 ;;; (message "Symbolic link to file in buffer %s"
650 ;;; (buffer-name linked-buf))))
651 (setq buf (create-file-buffer filename))
652 (set-buffer buf)
653 (erase-buffer)
654 (condition-case ()
655 (insert-file-contents filename t)
656 (file-error
657 (setq error t)
658 ;; Run find-file-not-found-hooks until one returns non-nil.
659 (let ((hooks find-file-not-found-hooks))
660 (while (and hooks
661 (not (and (funcall (car hooks))
662 ;; If a hook succeeded, clear error.
663 (progn (setq error nil)
664 ;; Also exit the loop.
665 t))))
666 (setq hooks (cdr hooks))))))
667 ;; Find the file's truename, and maybe use that as visited name.
668 (setq buffer-file-truename (abbreviate-file-name truename))
669 (setq buffer-file-number number)
670 ;; On VMS, we may want to remember which directory in a search list
671 ;; the file was found in.
672 (and (eq system-type 'vax-vms)
673 (let (logical)
674 (if (string-match ":" (file-name-directory filename))
675 (setq logical (substring (file-name-directory filename)
676 0 (match-beginning 0))))
677 (not (member logical find-file-not-true-dirname-list)))
678 (setq buffer-file-name buffer-file-truename))
679 (if find-file-visit-truename
680 (setq buffer-file-name
681 (setq filename
682 (expand-file-name buffer-file-truename))))
683 ;; Set buffer's default directory to that of the file.
684 (setq default-directory (file-name-directory filename))
685 ;; Turn off backup files for certain file names. Since
686 ;; this is a permanent local, the major mode won't eliminate it.
687 (and (not (funcall backup-enable-predicate buffer-file-name))
688 (progn
689 (make-local-variable 'backup-inhibited)
690 (setq backup-inhibited t)))
691 (after-find-file error (not nowarn))))
692 buf)))
693 \f
694 (defun after-find-file (&optional error warn noauto)
695 "Called after finding a file and by the default revert function.
696 Sets buffer mode, parses local variables.
697 Optional args ERROR, WARN, and NOAUTO: ERROR non-nil means there was an
698 error in reading the file. WARN non-nil means warn if there
699 exists an auto-save file more recent than the visited file.
700 NOAUTO means don't mess with auto-save mode.
701 Finishes by calling the functions in `find-file-hooks'."
702 (setq buffer-read-only (not (file-writable-p buffer-file-name)))
703 (if noninteractive
704 nil
705 (let* (not-serious
706 (msg
707 (cond ((and error (file-attributes buffer-file-name))
708 (setq buffer-read-only t)
709 "File exists, but cannot be read.")
710 ((not buffer-read-only)
711 (if (and warn
712 (file-newer-than-file-p (make-auto-save-file-name)
713 buffer-file-name))
714 "Auto save file is newer; consider M-x recover-file"
715 (setq not-serious t)
716 (if error "(New file)" nil)))
717 ((not error)
718 (setq not-serious t)
719 "Note: file is write protected")
720 ((file-attributes (directory-file-name default-directory))
721 "File not found and directory write-protected")
722 ((file-exists-p (file-name-directory buffer-file-name))
723 (setq buffer-read-only nil))
724 (t
725 (setq buffer-read-only nil)
726 (if (file-exists-p (file-name-directory (directory-file-name (file-name-directory buffer-file-name))))
727 "Use M-x make-dir RET RET to create the directory"
728 "Use C-u M-x make-dir RET RET to create directory and its parents")))))
729 (if msg
730 (progn
731 (message msg)
732 (or not-serious (sit-for 1 nil t)))))
733 (if (and auto-save-default (not noauto))
734 (auto-save-mode t)))
735 (normal-mode t)
736 (mapcar 'funcall find-file-hooks))
737
738 (defun normal-mode (&optional find-file)
739 "Choose the major mode for this buffer automatically.
740 Also sets up any specified local variables of the file.
741 Uses the visited file name, the -*- line, and the local variables spec.
742
743 This function is called automatically from `find-file'. In that case,
744 we may set up specified local variables depending on the value of
745 `enable-local-variables': if it is t, we do; if it is nil, we don't;
746 otherwise, we query. `enable-local-variables' is ignored if you
747 run `normal-mode' explicitly."
748 (interactive)
749 (or find-file (funcall (or default-major-mode 'fundamental-mode)))
750 (condition-case err
751 (set-auto-mode)
752 (error (message "File mode specification error: %s"
753 (prin1-to-string err))))
754 (condition-case err
755 (let ((enable-local-variables (or (not find-file)
756 enable-local-variables)))
757 (hack-local-variables))
758 (error (message "File local-variables error: %s"
759 (prin1-to-string err)))))
760
761 (defvar auto-mode-alist (mapcar 'purecopy
762 '(("\\.text\\'" . text-mode)
763 ("\\.c\\'" . c-mode)
764 ("\\.h\\'" . c-mode)
765 ("\\.tex\\'" . TeX-mode)
766 ("\\.ltx\\'" . LaTeX-mode)
767 ("\\.el\\'" . emacs-lisp-mode)
768 ("\\.mm\\'" . nroff-mode)
769 ("\\.me\\'" . nroff-mode)
770 ("\\.ms\\'" . nroff-mode)
771 ("\\.man\\'" . nroff-mode)
772 ("\\.scm\\'" . scheme-mode)
773 ("\\.l\\'" . lisp-mode)
774 ("\\.lisp\\'" . lisp-mode)
775 ("\\.f\\'" . fortran-mode)
776 ("\\.for\\'" . fortran-mode)
777 ("\\.mss\\'" . scribe-mode)
778 ("\\.pl\\'" . prolog-mode)
779 ("\\.cc\\'" . c++-mode)
780 ("\\.hh\\'" . c++-mode)
781 ("\\.C\\'" . c++-mode)
782 ("\\.H\\'" . c++-mode)
783 ;;; ("\\.mk\\'" . makefile-mode)
784 ;;; ("[Mm]akefile" . makefile-mode)
785 ;;; Less common extensions come here
786 ;;; so more common ones above are found faster.
787 ("\\.s\\'" . asm-mode)
788 ("ChangeLog\\'" . change-log-mode)
789 ("ChangeLog.[0-9]+\\'" . change-log-mode)
790 ("\\$CHANGE_LOG\\$\\.TXT" . change-log-mode)
791 ;; The following should come after the ChangeLog pattern
792 ;; for the sake of ChangeLog.1, etc.
793 ("\\.[12345678]\\'" . nroff-mode)
794 ("\\.TeX\\'" . TeX-mode)
795 ("\\.sty\\'" . LaTeX-mode)
796 ("\\.bbl\\'" . LaTeX-mode)
797 ("\\.bib\\'" . bibtex-mode)
798 ("\\.article\\'" . text-mode)
799 ("\\.letter\\'" . text-mode)
800 ("\\.texinfo\\'" . texinfo-mode)
801 ("\\.texi\\'" . texinfo-mode)
802 ("\\.lsp\\'" . lisp-mode)
803 ("\\.awk\\'" . awk-mode)
804 ("\\.prolog\\'" . prolog-mode)
805 ("\\.tar\\'" . tar-mode)
806 ;; Mailer puts message to be edited in
807 ;; /tmp/Re.... or Message
808 ("^/tmp/Re" . text-mode)
809 ("/Message[0-9]*\\'" . text-mode)
810 ;; some news reader is reported to use this
811 ("^/tmp/fol/" . text-mode)
812 ("\\.y\\'" . c-mode)
813 ("\\.lex\\'" . c-mode)
814 ("\\.oak\\'" . scheme-mode)
815 ("\\.scm.[0-9]*\\'" . scheme-mode)
816 ("\\.sgm\\'" . sgml-mode)
817 ("\\.sgml\\'" . sgml-mode)
818 ("\\.dtd\\'" . sgml-mode)
819 ;; .emacs following a directory delimiter
820 ;; in either Unix or VMS syntax.
821 ("[]>:/]\\..*emacs\\'" . emacs-lisp-mode)
822 ("\\.ml\\'" . lisp-mode)))
823 "\
824 Alist of filename patterns vs corresponding major mode functions.
825 Each element looks like (REGEXP . FUNCTION).
826 Visiting a file whose name matches REGEXP causes FUNCTION to be called.")
827
828 (defconst inhibit-local-variables-regexps '("\\.tar$")
829 "List of regexps; if one matches a file name, don't look for local vars.")
830
831 (defun set-auto-mode ()
832 "Select major mode appropriate for current buffer.
833 This checks for a -*- mode tag in the buffer's text, or
834 compares the filename against the entries in auto-mode-alist. It does
835 not check for the \"mode:\" local variable in the Local Variables
836 section of the file; for that, use `hack-local-variables'.
837
838 If `enable-local-variables' is nil, this function does not check for a
839 -*- mode tag."
840 ;; Look for -*-MODENAME-*- or -*- ... mode: MODENAME; ... -*-
841 (let (beg end done)
842 (save-excursion
843 (goto-char (point-min))
844 (skip-chars-forward " \t\n")
845 (and enable-local-variables
846 ;; Don't look for -*- if this file name matches any
847 ;; of the regexps in inhibit-local-variables-regexps.
848 (let ((temp inhibit-local-variables-regexps))
849 (while (and temp
850 (not (string-match (car temp)
851 buffer-file-name)))
852 (setq temp (cdr temp)))
853 (not temp))
854 (search-forward "-*-" (save-excursion
855 ;; If the file begins with "#!"
856 ;; (exec interpreter magic), look
857 ;; for mode frobs in the first two
858 ;; lines. You cannot necessarily
859 ;; put them in the first line of
860 ;; such a file without screwing up
861 ;; the interpreter invocation.
862 (end-of-line (and (looking-at "^#!") 2))
863 (point)) t)
864 (progn
865 (skip-chars-forward " \t")
866 (setq beg (point))
867 (search-forward "-*-"
868 (save-excursion (end-of-line) (point))
869 t))
870 (progn
871 (forward-char -3)
872 (skip-chars-backward " \t")
873 (setq end (point))
874 (goto-char beg)
875 (if (save-excursion (search-forward ":" end t))
876 ;; Find all specifications for the `mode:' variable
877 ;; and execute hem left to right.
878 (while (let ((case-fold-search t))
879 (search-forward "mode:" end t))
880 (skip-chars-forward " \t")
881 (setq beg (point))
882 (if (search-forward ";" end t)
883 (forward-char -1)
884 (goto-char end))
885 (skip-chars-backward " \t")
886 (funcall (intern (concat (downcase (buffer-substring beg (point))) "-mode"))))
887 ;; Simple -*-MODE-*- case.
888 (funcall (intern (concat (downcase (buffer-substring beg end)) "-mode"))))
889 (setq done t)))
890 ;; If we didn't find a mode from a -*- line, try using the file name.
891 (if (and (not done) buffer-file-name)
892 (let ((alist auto-mode-alist)
893 (name buffer-file-name)
894 mode)
895 (let ((case-fold-search (eq system-type 'vax-vms)))
896 ;; Remove backup-suffixes from file name.
897 (setq name (file-name-sans-versions name))
898 ;; Find first matching alist entry.
899 (while (and (not mode) alist)
900 (if (string-match (car (car alist)) name)
901 (setq mode (cdr (car alist))))
902 (setq alist (cdr alist))))
903 (if mode (funcall mode)))))))
904
905 (defun hack-local-variables-prop-line ()
906 ;; Set local variables specified in the -*- line.
907 ;; Ignore any specification for `mode:';
908 ;; set-auto-mode should already have handled that.
909 (save-excursion
910 (goto-char (point-min))
911 (skip-chars-forward " \t\n\r")
912 (let ((result '())
913 (end (save-excursion (end-of-line) (point))))
914 ;; Parse the -*- line into the `result' alist.
915 (cond ((not (search-forward "-*-" end t))
916 ;; doesn't have one.
917 nil)
918 ((looking-at "[ \t]*\\([^ \t\n\r:;]+\\)\\([ \t]*-\\*-\\)")
919 ;; Simple form: "-*- MODENAME -*-".
920 (setq result
921 (list (cons 'mode
922 (intern (buffer-substring
923 (match-beginning 1)
924 (match-end 1)))))))
925 (t
926 ;; Hairy form: '-*-' [ <variable> ':' <value> ';' ]* '-*-'
927 ;; (last ";" is optional).
928 (save-excursion
929 (if (search-forward "-*-" end t)
930 (setq end (- (point) 3))
931 (error "-*- not terminated before end of line")))
932 (while (< (point) end)
933 (or (looking-at "[ \t]*\\([^ \t\n:]+\\)[ \t]*:[ \t]*")
934 (error "malformed -*- line"))
935 (goto-char (match-end 0))
936 (let ((key (intern (downcase (buffer-substring
937 (match-beginning 1)
938 (match-end 1)))))
939 (val (save-restriction
940 (narrow-to-region (point) end)
941 (read (current-buffer)))))
942 (setq result (cons (cons key val) result))
943 (skip-chars-forward " \t;")))
944 (setq result (nreverse result))))
945
946 (if (and result
947 (or (eq enable-local-variables t)
948 (and enable-local-variables
949 (save-window-excursion
950 (condition-case nil
951 (switch-to-buffer (current-buffer))
952 (error
953 ;; If we fail to switch in the selected window,
954 ;; it is probably a minibuffer.
955 ;; So try another window.
956 (condition-case nil
957 (switch-to-buffer-other-window (current-buffer))
958 (error
959 (switch-to-buffer-other-frame (current-buffer))))))
960 (y-or-n-p (format "Set local variables as specified in -*- line of %s? "
961 (file-name-nondirectory buffer-file-name)))))))
962 (while result
963 (let ((key (car (car result)))
964 (val (cdr (car result))))
965 (or (eq key 'mode)
966 (hack-one-local-variable key val)))
967 (setq result (cdr result)))))))
968
969 (defun hack-local-variables ()
970 "Parse and put into effect this buffer's local variables spec."
971 (hack-local-variables-prop-line)
972 ;; Look for "Local variables:" line in last page.
973 (save-excursion
974 (goto-char (point-max))
975 (search-backward "\n\^L" (max (- (point-max) 3000) (point-min)) 'move)
976 (if (let ((case-fold-search t))
977 (and (search-forward "Local Variables:" nil t)
978 (or (eq enable-local-variables t)
979 (and enable-local-variables
980 (save-window-excursion
981 (switch-to-buffer (current-buffer))
982 (save-excursion
983 (beginning-of-line)
984 (set-window-start (selected-window) (point)))
985 (y-or-n-p (format "Set local variables as specified at end of %s? "
986 (if buffer-file-name
987 (file-name-nondirectory
988 buffer-file-name)
989 (concat "buffer "
990 (buffer-name))))))))))
991 (let ((continue t)
992 prefix prefixlen suffix beg
993 (enable-local-eval enable-local-eval))
994 ;; The prefix is what comes before "local variables:" in its line.
995 ;; The suffix is what comes after "local variables:" in its line.
996 (skip-chars-forward " \t")
997 (or (eolp)
998 (setq suffix (buffer-substring (point)
999 (progn (end-of-line) (point)))))
1000 (goto-char (match-beginning 0))
1001 (or (bolp)
1002 (setq prefix
1003 (buffer-substring (point)
1004 (progn (beginning-of-line) (point)))))
1005
1006 (if prefix (setq prefixlen (length prefix)
1007 prefix (regexp-quote prefix)))
1008 (if suffix (setq suffix (concat (regexp-quote suffix) "$")))
1009 (while continue
1010 ;; Look at next local variable spec.
1011 (if selective-display (re-search-forward "[\n\C-m]")
1012 (forward-line 1))
1013 ;; Skip the prefix, if any.
1014 (if prefix
1015 (if (looking-at prefix)
1016 (forward-char prefixlen)
1017 (error "Local variables entry is missing the prefix")))
1018 ;; Find the variable name; strip whitespace.
1019 (skip-chars-forward " \t")
1020 (setq beg (point))
1021 (skip-chars-forward "^:\n")
1022 (if (eolp) (error "Missing colon in local variables entry"))
1023 (skip-chars-backward " \t")
1024 (let* ((str (buffer-substring beg (point)))
1025 (var (read str))
1026 val)
1027 ;; Setting variable named "end" means end of list.
1028 (if (string-equal (downcase str) "end")
1029 (setq continue nil)
1030 ;; Otherwise read the variable value.
1031 (skip-chars-forward "^:")
1032 (forward-char 1)
1033 (setq val (read (current-buffer)))
1034 (skip-chars-backward "\n")
1035 (skip-chars-forward " \t")
1036 (or (if suffix (looking-at suffix) (eolp))
1037 (error "Local variables entry is terminated incorrectly"))
1038 ;; Set the variable. "Variables" mode and eval are funny.
1039 (hack-one-local-variable var val))))))))
1040
1041 (defconst ignored-local-variables
1042 '(enable-local-eval)
1043 "Variables to be ignored in a file's local variable spec.")
1044
1045 ;; "Set" one variable in a local variables spec.
1046 ;; A few variable names are treated specially.
1047 (defun hack-one-local-variable (var val)
1048 (cond ((eq var 'mode)
1049 (funcall (intern (concat (downcase (symbol-name val))
1050 "-mode"))))
1051 ((memq var ignored-local-variables)
1052 nil)
1053 ;; "Setting" eval means either eval it or do nothing.
1054 ;; Likewise for setting hook variables.
1055 ((or (eq var 'eval)
1056 (string-match "-hooks?$\\|-functions?$" (symbol-name var)))
1057 (if (and (not (string= (user-login-name) "root"))
1058 (or (eq enable-local-eval t)
1059 (and enable-local-eval
1060 (save-window-excursion
1061 (switch-to-buffer (current-buffer))
1062 (save-excursion
1063 (beginning-of-line)
1064 (set-window-start (selected-window) (point)))
1065 (setq enable-local-eval
1066 (y-or-n-p (format "Process `eval' or hook local variables in file %s? "
1067 (file-name-nondirectory buffer-file-name))))))))
1068 (if (eq var 'eval)
1069 (save-excursion (eval val))
1070 (make-local-variable var)
1071 (set var val))
1072 (message "Ignoring `eval:' in file's local variables")))
1073 ;; Ordinary variable, really set it.
1074 (t (make-local-variable var)
1075 (set var val))))
1076
1077 \f
1078 (defun set-visited-file-name (filename)
1079 "Change name of file visited in current buffer to FILENAME.
1080 The next time the buffer is saved it will go in the newly specified file.
1081 nil or empty string as argument means make buffer not be visiting any file.
1082 Remember to delete the initial contents of the minibuffer
1083 if you wish to pass an empty string as the argument."
1084 (interactive "FSet visited file name: ")
1085 (if filename
1086 (setq filename
1087 (if (string-equal filename "")
1088 nil
1089 (expand-file-name filename))))
1090 (or (equal filename buffer-file-name)
1091 (null filename)
1092 (progn
1093 (lock-buffer filename)
1094 (unlock-buffer)))
1095 (setq buffer-file-name filename)
1096 (if filename ; make buffer name reflect filename.
1097 (let ((new-name (file-name-nondirectory buffer-file-name)))
1098 (if (string= new-name "")
1099 (error "Empty file name"))
1100 (if (eq system-type 'vax-vms)
1101 (setq new-name (downcase new-name)))
1102 (setq default-directory (file-name-directory buffer-file-name))
1103 (or (string= new-name (buffer-name))
1104 (rename-buffer new-name t))))
1105 (setq buffer-backed-up nil)
1106 (clear-visited-file-modtime)
1107 (if filename
1108 (progn
1109 (setq buffer-file-truename
1110 (abbreviate-file-name (file-truename buffer-file-name)))
1111 (if find-file-visit-truename
1112 (setq buffer-file-name buffer-file-truename))
1113 (setq buffer-file-number (nth 10 (file-attributes buffer-file-name))))
1114 (setq buffer-file-truename nil buffer-file-number nil))
1115 ;; write-file-hooks is normally used for things like ftp-find-file
1116 ;; that visit things that are not local files as if they were files.
1117 ;; Changing to visit an ordinary local file instead should flush the hook.
1118 (kill-local-variable 'write-file-hooks)
1119 (kill-local-variable 'local-write-file-hooks)
1120 (kill-local-variable 'revert-buffer-function)
1121 (kill-local-variable 'backup-inhibited)
1122 ;; Turn off backup files for certain file names.
1123 ;; Since this is a permanent local, the major mode won't eliminate it.
1124 (and (not (funcall backup-enable-predicate buffer-file-name))
1125 (progn
1126 (make-local-variable 'backup-inhibited)
1127 (setq backup-inhibited t)))
1128 (let ((oauto buffer-auto-save-file-name))
1129 ;; If auto-save was not already on, turn it on if appropriate.
1130 (if (not buffer-auto-save-file-name)
1131 (and buffer-file-name auto-save-default
1132 (auto-save-mode t))
1133 ;; If auto save is on, start using a new name.
1134 ;; We deliberately don't rename or delete the old auto save
1135 ;; for the old visited file name. This is because perhaps
1136 ;; the user wants to save the new state and then compare with the
1137 ;; previous state from the auto save file.
1138 (setq buffer-auto-save-file-name
1139 (make-auto-save-file-name)))
1140 ;; Rename the old auto save file if any.
1141 (and oauto buffer-auto-save-file-name
1142 (file-exists-p oauto)
1143 (rename-file oauto buffer-auto-save-file-name t)))
1144 (if buffer-file-name
1145 (set-buffer-modified-p t)))
1146
1147 (defun write-file (filename)
1148 "Write current buffer into file FILENAME.
1149 Makes buffer visit that file, and marks it not modified.
1150 If the buffer is already visiting a file, you can specify
1151 a directory name as FILENAME, to write a file of the same
1152 old name in that directory."
1153 ;; (interactive "FWrite file: ")
1154 (interactive
1155 (list (if buffer-file-name
1156 (read-file-name "Write file: "
1157 nil nil nil nil)
1158 (read-file-name "Write file: "
1159 (cdr (assq 'default-directory
1160 (buffer-local-variables)))
1161 nil nil (buffer-name)))))
1162 (or (null filename) (string-equal filename "")
1163 (progn
1164 ;; If arg is just a directory,
1165 ;; use same file name, but in that directory.
1166 (if (and (file-directory-p filename) buffer-file-name)
1167 (setq filename (concat (file-name-as-directory filename)
1168 (file-name-nondirectory buffer-file-name))))
1169 (set-visited-file-name filename)))
1170 (set-buffer-modified-p t)
1171 (save-buffer))
1172 \f
1173 (defun backup-buffer ()
1174 "Make a backup of the disk file visited by the current buffer, if appropriate.
1175 This is normally done before saving the buffer the first time.
1176 If the value is non-nil, it is the result of `file-modes' on the original
1177 file; this means that the caller, after saving the buffer, should change
1178 the modes of the new file to agree with the old modes."
1179 (if (and make-backup-files (not backup-inhibited)
1180 (not buffer-backed-up)
1181 (file-exists-p buffer-file-name)
1182 (memq (aref (elt (file-attributes buffer-file-name) 8) 0)
1183 '(?- ?l)))
1184 (let ((real-file-name buffer-file-name)
1185 backup-info backupname targets setmodes)
1186 ;; If specified name is a symbolic link, chase it to the target.
1187 ;; Thus we make the backups in the directory where the real file is.
1188 (setq real-file-name (file-chase-links real-file-name))
1189 (setq backup-info (find-backup-file-name real-file-name)
1190 backupname (car backup-info)
1191 targets (cdr backup-info))
1192 ;;; (if (file-directory-p buffer-file-name)
1193 ;;; (error "Cannot save buffer in directory %s" buffer-file-name))
1194 (condition-case ()
1195 (let ((delete-old-versions
1196 ;; If have old versions to maybe delete,
1197 ;; ask the user to confirm now, before doing anything.
1198 ;; But don't actually delete til later.
1199 (and targets
1200 (or (eq trim-versions-without-asking t) (eq trim-versions-without-asking nil))
1201 (or trim-versions-without-asking
1202 (y-or-n-p (format "Delete excess backup versions of %s? "
1203 real-file-name))))))
1204 ;; Actually write the back up file.
1205 (condition-case ()
1206 (if (or file-precious-flag
1207 ; (file-symlink-p buffer-file-name)
1208 backup-by-copying
1209 (and backup-by-copying-when-linked
1210 (> (file-nlinks real-file-name) 1))
1211 (and backup-by-copying-when-mismatch
1212 (let ((attr (file-attributes real-file-name)))
1213 (or (nth 9 attr)
1214 (/= (nth 2 attr) (user-uid))))))
1215 (condition-case ()
1216 (copy-file real-file-name backupname t t)
1217 (file-error
1218 ;; If copying fails because file BACKUPNAME
1219 ;; is not writable, delete that file and try again.
1220 (if (and (file-exists-p backupname)
1221 (not (file-writable-p backupname)))
1222 (delete-file backupname))
1223 (copy-file real-file-name backupname t t)))
1224 ;; rename-file should delete old backup.
1225 (rename-file real-file-name backupname t)
1226 (setq setmodes (file-modes backupname)))
1227 (file-error
1228 ;; If trouble writing the backup, write it in ~.
1229 (setq backupname (expand-file-name "~/%backup%~"))
1230 (message "Cannot write backup file; backing up in ~/%%backup%%~")
1231 (sleep-for 1)
1232 (condition-case ()
1233 (copy-file real-file-name backupname t t)
1234 (file-error
1235 ;; If copying fails because file BACKUPNAME
1236 ;; is not writable, delete that file and try again.
1237 (if (and (file-exists-p backupname)
1238 (not (file-writable-p backupname)))
1239 (delete-file backupname))
1240 (copy-file real-file-name backupname t t)))))
1241 (setq buffer-backed-up t)
1242 ;; Now delete the old versions, if desired.
1243 (if delete-old-versions
1244 (while targets
1245 (condition-case ()
1246 (delete-file (car targets))
1247 (file-error nil))
1248 (setq targets (cdr targets))))
1249 setmodes)
1250 (file-error nil)))))
1251
1252 (defun file-name-sans-versions (name &optional keep-backup-version)
1253 "Return FILENAME sans backup versions or strings.
1254 This is a separate procedure so your site-init or startup file can
1255 redefine it.
1256 If the optional argument KEEP-BACKUP-VERSION is non-nil,
1257 we do not remove backup version numbers, only true file version numbers."
1258 (let ((handler (find-file-name-handler name)))
1259 (if handler
1260 (funcall handler 'file-name-sans-versions name keep-backup-version)
1261 (substring name 0
1262 (if (eq system-type 'vax-vms)
1263 ;; VMS version number is (a) semicolon, optional
1264 ;; sign, zero or more digits or (b) period, option
1265 ;; sign, zero or more digits, provided this is the
1266 ;; second period encountered outside of the
1267 ;; device/directory part of the file name.
1268 (or (string-match ";[---+]?[0-9]*\\'" name)
1269 (if (string-match "\\.[^]>:]*\\(\\.[---+]?[0-9]*\\)\\'"
1270 name)
1271 (match-beginning 1))
1272 (length name))
1273 (if keep-backup-version
1274 (length name)
1275 (or (string-match "\\.~[0-9]+~\\'" name)
1276 (string-match "~\\'" name)
1277 (length name))))))))
1278
1279 (defun make-backup-file-name (file)
1280 "Create the non-numeric backup file name for FILE.
1281 This is a separate function so you can redefine it for customization."
1282 (concat file "~"))
1283
1284 (defun backup-file-name-p (file)
1285 "Return non-nil if FILE is a backup file name (numeric or not).
1286 This is a separate function so you can redefine it for customization.
1287 You may need to redefine `file-name-sans-versions' as well."
1288 (string-match "~$" file))
1289
1290 ;; This is used in various files.
1291 ;; The usage of bv-length is not very clean,
1292 ;; but I can't see a good alternative,
1293 ;; so as of now I am leaving it alone.
1294 (defun backup-extract-version (fn)
1295 "Given the name of a numeric backup file, return the backup number.
1296 Uses the free variable `bv-length', whose value should be
1297 the index in the name where the version number begins."
1298 (if (and (string-match "[0-9]+~$" fn bv-length)
1299 (= (match-beginning 0) bv-length))
1300 (string-to-int (substring fn bv-length -1))
1301 0))
1302
1303 ;; I believe there is no need to alter this behavior for VMS;
1304 ;; since backup files are not made on VMS, it should not get called.
1305 (defun find-backup-file-name (fn)
1306 "Find a file name for a backup file, and suggestions for deletions.
1307 Value is a list whose car is the name for the backup file
1308 and whose cdr is a list of old versions to consider deleting now."
1309 (if (eq version-control 'never)
1310 (list (make-backup-file-name fn))
1311 (let* ((base-versions (concat (file-name-nondirectory fn) ".~"))
1312 (bv-length (length base-versions))
1313 possibilities
1314 (versions nil)
1315 (high-water-mark 0)
1316 (deserve-versions-p nil)
1317 (number-to-delete 0))
1318 (condition-case ()
1319 (setq possibilities (file-name-all-completions
1320 base-versions
1321 (file-name-directory fn))
1322 versions (sort (mapcar
1323 (function backup-extract-version)
1324 possibilities)
1325 '<)
1326 high-water-mark (apply 'max 0 versions)
1327 deserve-versions-p (or version-control
1328 (> high-water-mark 0))
1329 number-to-delete (- (length versions)
1330 kept-old-versions kept-new-versions -1))
1331 (file-error
1332 (setq possibilities nil)))
1333 (if (not deserve-versions-p)
1334 (list (make-backup-file-name fn))
1335 (cons (concat fn ".~" (int-to-string (1+ high-water-mark)) "~")
1336 (if (and (> number-to-delete 0)
1337 ;; Delete nothing if there is overflow
1338 ;; in the number of versions to keep.
1339 (>= (+ kept-new-versions kept-old-versions -1) 0))
1340 (mapcar (function (lambda (n)
1341 (concat fn ".~" (int-to-string n) "~")))
1342 (let ((v (nthcdr kept-old-versions versions)))
1343 (rplacd (nthcdr (1- number-to-delete) v) ())
1344 v))))))))
1345
1346 (defun file-nlinks (filename)
1347 "Return number of names file FILENAME has."
1348 (car (cdr (file-attributes filename))))
1349
1350 (defun file-relative-name-1 (directory)
1351 (cond ((string= directory "/")
1352 filename)
1353 ((string-match (concat "^" (regexp-quote directory))
1354 filename)
1355 (substring filename (match-end 0)))
1356 (t
1357 (file-relative-name-1
1358 (file-name-directory (substring directory 0 -1))))))
1359
1360 (defun file-relative-name (filename &optional directory)
1361 "Convert FILENAME to be relative to DIRECTORY (default: default-directory)."
1362 (setq filename (expand-file-name filename)
1363 directory (file-name-as-directory (expand-file-name
1364 (or directory default-directory))))
1365 (file-relative-name-1 directory))
1366 \f
1367 (defun save-buffer (&optional args)
1368 "Save current buffer in visited file if modified. Versions described below.
1369 By default, makes the previous version into a backup file
1370 if previously requested or if this is the first save.
1371 With 1 or 3 \\[universal-argument]'s, marks this version
1372 to become a backup when the next save is done.
1373 With 2 or 3 \\[universal-argument]'s,
1374 unconditionally makes the previous version into a backup file.
1375 With argument of 0, never makes the previous version into a backup file.
1376
1377 If a file's name is FOO, the names of its numbered backup versions are
1378 FOO.~i~ for various integers i. A non-numbered backup file is called FOO~.
1379 Numeric backups (rather than FOO~) will be made if value of
1380 `version-control' is not the atom `never' and either there are already
1381 numeric versions of the file being backed up, or `version-control' is
1382 non-nil.
1383 We don't want excessive versions piling up, so there are variables
1384 `kept-old-versions', which tells Emacs how many oldest versions to keep,
1385 and `kept-new-versions', which tells how many newest versions to keep.
1386 Defaults are 2 old versions and 2 new.
1387 `dired-kept-versions' controls dired's clean-directory (.) command.
1388 If `trim-versions-without-asking' is nil, system will query user
1389 before trimming versions. Otherwise it does it silently."
1390 (interactive "p")
1391 (let ((modp (buffer-modified-p))
1392 (large (> (buffer-size) 50000))
1393 (make-backup-files (and make-backup-files (not (eq args 0)))))
1394 (and modp (memq args '(16 64)) (setq buffer-backed-up nil))
1395 (if (and modp large) (message "Saving file %s..." (buffer-file-name)))
1396 (basic-save-buffer)
1397 (and modp (memq args '(4 64)) (setq buffer-backed-up nil))))
1398
1399 (defun delete-auto-save-file-if-necessary (&optional force)
1400 "Delete auto-save file for current buffer if `delete-auto-save-files' is t.
1401 Normally delete only if the file was written by this Emacs since
1402 the last real save, but optional arg FORCE non-nil means delete anyway."
1403 (and buffer-auto-save-file-name delete-auto-save-files
1404 (not (string= buffer-file-name buffer-auto-save-file-name))
1405 (or force (recent-auto-save-p))
1406 (progn
1407 (condition-case ()
1408 (delete-file buffer-auto-save-file-name)
1409 (file-error nil))
1410 (set-buffer-auto-saved))))
1411
1412 (defun basic-save-buffer ()
1413 "Save the current buffer in its visited file, if it has been modified."
1414 (interactive)
1415 (if (buffer-modified-p)
1416 (let ((recent-save (recent-auto-save-p))
1417 setmodes tempsetmodes)
1418 ;; On VMS, rename file and buffer to get rid of version number.
1419 (if (and (eq system-type 'vax-vms)
1420 (not (string= buffer-file-name
1421 (file-name-sans-versions buffer-file-name))))
1422 (let (buffer-new-name)
1423 ;; Strip VMS version number before save.
1424 (setq buffer-file-name
1425 (file-name-sans-versions buffer-file-name))
1426 ;; Construct a (unique) buffer name to correspond.
1427 (let ((buf (create-file-buffer (downcase buffer-file-name))))
1428 (setq buffer-new-name (buffer-name buf))
1429 (kill-buffer buf))
1430 (rename-buffer buffer-new-name)))
1431 ;; If buffer has no file name, ask user for one.
1432 (or buffer-file-name
1433 (set-visited-file-name
1434 (expand-file-name (read-file-name "File to save in: ") nil)))
1435 (or (verify-visited-file-modtime (current-buffer))
1436 (not (file-exists-p buffer-file-name))
1437 (yes-or-no-p
1438 (format "%s has changed since visited or saved. Save anyway? "
1439 (file-name-nondirectory buffer-file-name)))
1440 (error "Save not confirmed"))
1441 (save-restriction
1442 (widen)
1443 (and (> (point-max) 1)
1444 (/= (char-after (1- (point-max))) ?\n)
1445 (or (eq require-final-newline t)
1446 (and require-final-newline
1447 (y-or-n-p
1448 (format "Buffer %s does not end in newline. Add one? "
1449 (buffer-name)))))
1450 (save-excursion
1451 (goto-char (point-max))
1452 (insert ?\n)))
1453 (let ((hooks (append write-contents-hooks local-write-file-hooks
1454 write-file-hooks))
1455 (done nil))
1456 (while (and hooks
1457 (not (setq done (funcall (car hooks)))))
1458 (setq hooks (cdr hooks)))
1459 ;; If a hook returned t, file is already "written".
1460 (cond ((not done)
1461 (if (not (file-writable-p buffer-file-name))
1462 (let ((dir (file-name-directory buffer-file-name)))
1463 (if (not (file-directory-p dir))
1464 (error "%s is not a directory" dir)
1465 (if (not (file-exists-p buffer-file-name))
1466 (error "Directory %s write-protected" dir)
1467 (if (yes-or-no-p
1468 (format "File %s is write-protected; try to save anyway? "
1469 (file-name-nondirectory
1470 buffer-file-name)))
1471 (setq tempsetmodes t)
1472 (error "Attempt to save to a file which you aren't allowed to write"))))))
1473 (or buffer-backed-up
1474 (setq setmodes (backup-buffer)))
1475 (if file-precious-flag
1476 ;; If file is precious, write temp name, then rename it.
1477 (let ((dir (file-name-directory buffer-file-name))
1478 (realname buffer-file-name)
1479 tempname temp nogood i succeed)
1480 (setq i 0)
1481 (setq nogood t)
1482 ;; Find the temporary name to write under.
1483 (while nogood
1484 (setq tempname (format "%s#tmp#%d" dir i))
1485 (setq nogood (file-exists-p tempname))
1486 (setq i (1+ i)))
1487 (unwind-protect
1488 (progn (clear-visited-file-modtime)
1489 (write-region (point-min) (point-max)
1490 tempname nil realname)
1491 (setq succeed t))
1492 ;; If writing the temp file fails,
1493 ;; delete the temp file.
1494 (or succeed (delete-file tempname)))
1495 ;; Since we have created an entirely new file
1496 ;; and renamed it, make sure it gets the
1497 ;; right permission bits set.
1498 (setq setmodes (file-modes buffer-file-name))
1499 ;; We succeeded in writing the temp file,
1500 ;; so rename it.
1501 (rename-file tempname buffer-file-name t))
1502 ;; If file not writable, see if we can make it writable
1503 ;; temporarily while we write it.
1504 ;; But no need to do so if we have just backed it up
1505 ;; (setmodes is set) because that says we're superseding.
1506 (cond ((and tempsetmodes (not setmodes))
1507 ;; Change the mode back, after writing.
1508 (setq setmodes (file-modes buffer-file-name))
1509 (set-file-modes buffer-file-name 511)))
1510 (write-region (point-min) (point-max)
1511 buffer-file-name nil t)))))
1512 (setq buffer-file-number (nth 10 (file-attributes buffer-file-name)))
1513 (if setmodes
1514 (condition-case ()
1515 (set-file-modes buffer-file-name setmodes)
1516 (error nil))))
1517 ;; If the auto-save file was recent before this command,
1518 ;; delete it now.
1519 (delete-auto-save-file-if-necessary recent-save)
1520 (run-hooks 'after-save-hook))
1521 (message "(No changes need to be saved)")))
1522
1523 (defun save-some-buffers (&optional arg exiting)
1524 "Save some modified file-visiting buffers. Asks user about each one.
1525 Optional argument (the prefix) non-nil means save all with no questions.
1526 Optional second argument EXITING means ask about certain non-file buffers
1527 as well as about file buffers."
1528 (interactive "P")
1529 (save-window-excursion
1530 (if (zerop (map-y-or-n-p
1531 (function
1532 (lambda (buffer)
1533 (and (buffer-modified-p buffer)
1534 (or
1535 (buffer-file-name buffer)
1536 (and exiting
1537 (progn
1538 (set-buffer buffer)
1539 (and buffer-offer-save (> (buffer-size) 0)))))
1540 (if arg
1541 t
1542 (if (buffer-file-name buffer)
1543 (format "Save file %s? "
1544 (buffer-file-name buffer))
1545 (format "Save buffer %s? "
1546 (buffer-name buffer)))))))
1547 (function
1548 (lambda (buffer)
1549 (set-buffer buffer)
1550 (save-buffer)))
1551 (buffer-list)
1552 '("buffer" "buffers" "save")
1553 (list (list ?\C-r (lambda (buf)
1554 (view-buffer buf)
1555 (setq view-exit-action
1556 '(lambda (ignore)
1557 (exit-recursive-edit)))
1558 (recursive-edit)
1559 ;; Return nil to ask about BUF again.
1560 nil)
1561 "display the current buffer"))
1562 ))
1563 (message "(No files need saving)"))))
1564 \f
1565 (defun not-modified (&optional arg)
1566 "Mark current buffer as unmodified, not needing to be saved.
1567 With prefix arg, mark buffer as modified, so \\[save-buffer] will save."
1568 (interactive "P")
1569 (message (if arg "Modification-flag set"
1570 "Modification-flag cleared"))
1571 (set-buffer-modified-p arg))
1572
1573 (defun toggle-read-only (&optional arg)
1574 "Change whether this buffer is visiting its file read-only.
1575 With arg, set read-only iff arg is positive."
1576 (interactive "P")
1577 (setq buffer-read-only
1578 (if (null arg)
1579 (not buffer-read-only)
1580 (> (prefix-numeric-value arg) 0)))
1581 ;; Force mode-line redisplay
1582 (set-buffer-modified-p (buffer-modified-p)))
1583
1584 (defun insert-file (filename)
1585 "Insert contents of file FILENAME into buffer after point.
1586 Set mark after the inserted text.
1587
1588 This function is meant for the user to run interactively.
1589 Don't call it from programs! Use `insert-file-contents' instead.
1590 \(Its calling sequence is different; see its documentation)."
1591 (interactive "*fInsert file: ")
1592 (if (file-directory-p filename)
1593 (signal 'file-error (list "Opening input file" "file is a directory"
1594 filename)))
1595 (let ((tem (insert-file-contents filename)))
1596 (push-mark (+ (point) (car (cdr tem))))))
1597
1598 (defun append-to-file (start end filename)
1599 "Append the contents of the region to the end of file FILENAME.
1600 When called from a function, expects three arguments,
1601 START, END and FILENAME. START and END are buffer positions
1602 saying what text to write."
1603 (interactive "r\nFAppend to file: ")
1604 (write-region start end filename t))
1605
1606 (defun file-newest-backup (filename)
1607 "Return most recent backup file for FILENAME or nil if no backups exist."
1608 (let* ((filename (expand-file-name filename))
1609 (file (file-name-nondirectory filename))
1610 (dir (file-name-directory filename))
1611 (comp (file-name-all-completions file dir))
1612 newest)
1613 (while comp
1614 (setq file (concat dir (car comp))
1615 comp (cdr comp))
1616 (if (and (backup-file-name-p file)
1617 (or (null newest) (file-newer-than-file-p file newest)))
1618 (setq newest file)))
1619 newest))
1620
1621 (defun rename-uniquely ()
1622 "Rename current buffer to a similar name not already taken.
1623 This function is useful for creating multiple shell process buffers
1624 or multiple mail buffers, etc."
1625 (interactive)
1626 (let* ((new-buf (generate-new-buffer (buffer-name)))
1627 (name (buffer-name new-buf)))
1628 (kill-buffer new-buf)
1629 (rename-buffer name)
1630 (set-buffer-modified-p (buffer-modified-p)))) ; force mode line update
1631
1632 (defun make-directory (dir &optional parents)
1633 "Create the directory DIR and any nonexistent parent dirs.
1634 Interactively, the default choice of directory to create
1635 is the current default directory for file names.
1636 That is useful when you have visited a file in a nonexistint directory.
1637
1638 Noninteractively, the second (optional) argument PARENTS says whether
1639 to create parent directories if they don't exist."
1640 (interactive
1641 (list (read-file-name "Make directory: " default-directory default-directory
1642 nil nil)
1643 t))
1644 (let ((handler (find-file-name-handler dir)))
1645 (if handler
1646 (funcall handler 'make-directory dir parents)
1647 (if (not parents)
1648 (make-directory-internal dir)
1649 (let ((dir (directory-file-name (expand-file-name dir)))
1650 create-list)
1651 (while (not (file-exists-p dir))
1652 (setq create-list (cons dir create-list)
1653 dir (directory-file-name (file-name-directory dir))))
1654 (while create-list
1655 (make-directory-internal (car create-list))
1656 (setq create-list (cdr create-list))))))))
1657 \f
1658 (put 'revert-buffer-function 'permanent-local t)
1659 (defvar revert-buffer-function nil
1660 "Function to use to revert this buffer, or nil to do the default.")
1661
1662 (put 'revert-buffer-insert-file-contents-function 'permanent-local t)
1663 (defvar revert-buffer-insert-file-contents-function nil
1664 "Function to use to insert contents when reverting this buffer.
1665 Gets two args, first the nominal file name to use,
1666 and second, t if reading the auto-save file.")
1667
1668 (defun revert-buffer (&optional ignore-auto noconfirm)
1669 "Replace the buffer text with the text of the visited file on disk.
1670 This undoes all changes since the file was visited or saved.
1671 With a prefix argument, offer to revert from latest auto-save file, if
1672 that is more recent than the visited file.
1673
1674 When called from lisp, the first argument is IGNORE-AUTO; only offer
1675 to revert from the auto-save file when this is nil. Note that the
1676 sense of this argument is the reverse of the prefix argument, for the
1677 sake of backward compatibility. IGNORE-AUTO is optional, defaulting
1678 to nil.
1679
1680 Optional second argument NOCONFIRM means don't ask for confirmation at
1681 all.
1682
1683 If the value of `revert-buffer-function' is non-nil, it is called to
1684 do the work."
1685 ;; I admit it's odd to reverse the sense of the prefix argument, but
1686 ;; there is a lot of code out there which assumes that the first
1687 ;; argument should be t to avoid consulting the auto-save file, and
1688 ;; there's no straightforward way to encourage authors to notice a
1689 ;; reversal of the argument sense. So I'm just changing the user
1690 ;; interface, but leaving the programmatic interface the same.
1691 (interactive (list (not prefix-arg)))
1692 (if revert-buffer-function
1693 (funcall revert-buffer-function ignore-auto noconfirm)
1694 (let* ((opoint (point))
1695 (auto-save-p (and (not ignore-auto)
1696 (recent-auto-save-p)
1697 buffer-auto-save-file-name
1698 (file-readable-p buffer-auto-save-file-name)
1699 (y-or-n-p
1700 "Buffer has been auto-saved recently. Revert from auto-save file? ")))
1701 (file-name (if auto-save-p
1702 buffer-auto-save-file-name
1703 buffer-file-name)))
1704 (cond ((null file-name)
1705 (error "Buffer does not seem to be associated with any file"))
1706 ((or noconfirm
1707 (yes-or-no-p (format "Revert buffer from file %s? "
1708 file-name)))
1709 ;; If file was backed up but has changed since,
1710 ;; we shd make another backup.
1711 (and (not auto-save-p)
1712 (not (verify-visited-file-modtime (current-buffer)))
1713 (setq buffer-backed-up nil))
1714 ;; Get rid of all undo records for this buffer.
1715 (or (eq buffer-undo-list t)
1716 (setq buffer-undo-list nil))
1717 (let ((buffer-read-only nil)
1718 ;; Don't make undo records for the reversion.
1719 (buffer-undo-list t))
1720 (if revert-buffer-insert-file-contents-function
1721 (funcall revert-buffer-insert-file-contents-function
1722 file-name auto-save-p)
1723 (if (not (file-exists-p file-name))
1724 (error "File %s no longer exists!" file-name))
1725 ;; Bind buffer-file-name to nil
1726 ;; so that we don't try to lock the file.
1727 (let ((buffer-file-name nil))
1728 (or auto-save-p
1729 (unlock-buffer))
1730 (erase-buffer))
1731 (insert-file-contents file-name (not auto-save-p))))
1732 (goto-char (min opoint (point-max)))
1733 (after-find-file nil nil t)
1734 t)))))
1735
1736 (defun recover-file (file)
1737 "Visit file FILE, but get contents from its last auto-save file."
1738 (interactive
1739 (let ((prompt-file buffer-file-name)
1740 (file-name nil)
1741 (file-dir nil))
1742 (and prompt-file
1743 (setq file-name (file-name-nondirectory prompt-file)
1744 file-dir (file-name-directory prompt-file)))
1745 (list (read-file-name "Recover file: "
1746 file-dir nil nil file-name))))
1747 (setq file (expand-file-name file))
1748 (if (auto-save-file-name-p file) (error "%s is an auto-save file" file))
1749 (let ((file-name (let ((buffer-file-name file))
1750 (make-auto-save-file-name))))
1751 (cond ((not (file-newer-than-file-p file-name file))
1752 (error "Auto-save file %s not current" file-name))
1753 ((save-window-excursion
1754 (if (not (eq system-type 'vax-vms))
1755 (with-output-to-temp-buffer "*Directory*"
1756 (buffer-disable-undo standard-output)
1757 (call-process "ls" nil standard-output nil
1758 (if (file-symlink-p file) "-lL" "-l")
1759 file file-name)))
1760 (yes-or-no-p (format "Recover auto save file %s? " file-name)))
1761 (switch-to-buffer (find-file-noselect file t))
1762 (let ((buffer-read-only nil))
1763 (erase-buffer)
1764 (insert-file-contents file-name nil))
1765 (after-find-file nil nil t))
1766 (t (error "Recover-file cancelled.")))))
1767
1768 (defun kill-some-buffers ()
1769 "For each buffer, ask whether to kill it."
1770 (interactive)
1771 (let ((list (buffer-list)))
1772 (while list
1773 (let* ((buffer (car list))
1774 (name (buffer-name buffer)))
1775 (and (not (string-equal name ""))
1776 (/= (aref name 0) ? )
1777 (yes-or-no-p
1778 (format "Buffer %s %s. Kill? "
1779 name
1780 (if (buffer-modified-p buffer)
1781 "HAS BEEN EDITED" "is unmodified")))
1782 (kill-buffer buffer)))
1783 (setq list (cdr list)))))
1784 \f
1785 (defun auto-save-mode (arg)
1786 "Toggle auto-saving of contents of current buffer.
1787 With prefix argument ARG, turn auto-saving on if positive, else off."
1788 (interactive "P")
1789 (setq buffer-auto-save-file-name
1790 (and (if (null arg)
1791 (not buffer-auto-save-file-name)
1792 (or (eq arg t) (listp arg) (and (integerp arg) (> arg 0))))
1793 (if (and buffer-file-name auto-save-visited-file-name
1794 (not buffer-read-only))
1795 buffer-file-name
1796 (make-auto-save-file-name))))
1797 (if (interactive-p)
1798 (message "Auto-save %s (in this buffer)"
1799 (if buffer-auto-save-file-name "on" "off")))
1800 buffer-auto-save-file-name)
1801
1802 (defun rename-auto-save-file ()
1803 "Adjust current buffer's auto save file name for current conditions.
1804 Also rename any existing auto save file, if it was made in this session."
1805 (let ((osave buffer-auto-save-file-name))
1806 (setq buffer-auto-save-file-name
1807 (make-auto-save-file-name))
1808 (if (and osave buffer-auto-save-file-name
1809 (not (string= buffer-auto-save-file-name buffer-file-name))
1810 (not (string= buffer-auto-save-file-name osave))
1811 (file-exists-p osave)
1812 (recent-auto-save-p))
1813 (rename-file osave buffer-auto-save-file-name t))))
1814
1815 (defun make-auto-save-file-name ()
1816 "Return file name to use for auto-saves of current buffer.
1817 Does not consider `auto-save-visited-file-name' as that variable is checked
1818 before calling this function. You can redefine this for customization.
1819 See also `auto-save-file-name-p'."
1820 (if buffer-file-name
1821 (concat (file-name-directory buffer-file-name)
1822 "#"
1823 (file-name-nondirectory buffer-file-name)
1824 "#")
1825 ;; For non-file bfr, use bfr name and Emacs pid.
1826 (expand-file-name (format "#%s#%s#" (buffer-name) (make-temp-name "")))))
1827
1828 (defun auto-save-file-name-p (filename)
1829 "Return non-nil if FILENAME can be yielded by `make-auto-save-file-name'.
1830 FILENAME should lack slashes. You can redefine this for customization."
1831 (string-match "^#.*#$" filename))
1832 \f
1833 (defconst list-directory-brief-switches
1834 (if (eq system-type 'vax-vms) "" "-CF")
1835 "*Switches for list-directory to pass to `ls' for brief listing,")
1836
1837 (defconst list-directory-verbose-switches
1838 (if (eq system-type 'vax-vms)
1839 "/PROTECTION/SIZE/DATE/OWNER/WIDTH=(OWNER:10)"
1840 "-l")
1841 "*Switches for list-directory to pass to `ls' for verbose listing,")
1842
1843 (defun list-directory (dirname &optional verbose)
1844 "Display a list of files in or matching DIRNAME, a la `ls'.
1845 DIRNAME is globbed by the shell if necessary.
1846 Prefix arg (second arg if noninteractive) means supply -l switch to `ls'.
1847 Actions controlled by variables `list-directory-brief-switches'
1848 and `list-directory-verbose-switches'."
1849 (interactive (let ((pfx current-prefix-arg))
1850 (list (read-file-name (if pfx "List directory (verbose): "
1851 "List directory (brief): ")
1852 nil default-directory nil)
1853 pfx)))
1854 (let ((switches (if verbose list-directory-verbose-switches
1855 list-directory-brief-switches)))
1856 (or dirname (setq dirname default-directory))
1857 (setq dirname (expand-file-name dirname))
1858 (with-output-to-temp-buffer "*Directory*"
1859 (buffer-disable-undo standard-output)
1860 (princ "Directory ")
1861 (princ dirname)
1862 (terpri)
1863 (save-excursion
1864 (set-buffer "*Directory*")
1865 (let ((wildcard (not (file-directory-p dirname))))
1866 (insert-directory dirname switches wildcard (not wildcard)))))))
1867
1868 (defvar insert-directory-program "ls"
1869 "Absolute or relative name of the `ls' program used by `insert-directory'.")
1870
1871 ;; insert-directory
1872 ;; - must insert _exactly_one_line_ describing FILE if WILDCARD and
1873 ;; FULL-DIRECTORY-P is nil.
1874 ;; The single line of output must display FILE's name as it was
1875 ;; given, namely, an absolute path name.
1876 ;; - must insert exactly one line for each file if WILDCARD or
1877 ;; FULL-DIRECTORY-P is t, plus one optional "total" line
1878 ;; before the file lines, plus optional text after the file lines.
1879 ;; Lines are delimited by "\n", so filenames containing "\n" are not
1880 ;; allowed.
1881 ;; File lines should display the basename.
1882 ;; - must be consistent with
1883 ;; - functions dired-move-to-filename, (these two define what a file line is)
1884 ;; dired-move-to-end-of-filename,
1885 ;; dired-between-files, (shortcut for (not (dired-move-to-filename)))
1886 ;; dired-insert-headerline
1887 ;; dired-after-subdir-garbage (defines what a "total" line is)
1888 ;; - variable dired-subdir-regexp
1889 (defun insert-directory (file switches &optional wildcard full-directory-p)
1890 "Insert directory listing for FILE, formatted according to SWITCHES.
1891 Leaves point after the inserted text.
1892 Optional third arg WILDCARD means treat FILE as shell wildcard.
1893 Optional fourth arg FULL-DIRECTORY-P means file is a directory and
1894 switches do not contain `d', so that a full listing is expected.
1895
1896 This works by running a directory listing program
1897 whose name is in the variable `insert-directory-program'.
1898 If WILDCARD, it also runs the shell specified by `shell-file-name'."
1899 (let ((handler (find-file-name-handler file)))
1900 (if handler
1901 (funcall handler 'insert-directory file switches
1902 wildcard full-directory-p)
1903 (if (eq system-type 'vax-vms)
1904 (vms-read-directory file switches (current-buffer))
1905 (if wildcard
1906 ;; Run ls in the directory of the file pattern we asked for.
1907 (let ((default-directory
1908 (if (file-name-absolute-p file)
1909 (file-name-directory file)
1910 (file-name-directory (expand-file-name file)))))
1911 (call-process shell-file-name nil t nil
1912 "-c" (concat insert-directory-program
1913 " -d " switches " "
1914 (file-name-nondirectory file))))
1915 ;; SunOS 4.1.3, SVr4 and others need the "." to list the
1916 ;; directory if FILE is a symbolic link.
1917 (call-process insert-directory-program nil t nil switches
1918 (if full-directory-p
1919 (concat (file-name-as-directory file) ".")
1920 file)))))))
1921
1922 (defun save-buffers-kill-emacs (&optional arg)
1923 "Offer to save each buffer, then kill this Emacs process.
1924 With prefix arg, silently save all file-visiting buffers, then kill."
1925 (interactive "P")
1926 (save-some-buffers arg t)
1927 (and (or (not (memq t (mapcar (function
1928 (lambda (buf) (and (buffer-file-name buf)
1929 (buffer-modified-p buf))))
1930 (buffer-list))))
1931 (yes-or-no-p "Modified buffers exist; exit anyway? "))
1932 (or (not (fboundp 'process-list))
1933 ;; process-list is not defined on VMS.
1934 (let ((processes (process-list))
1935 active)
1936 (while processes
1937 (and (memq (process-status (car processes)) '(run stop open))
1938 (let ((val (process-kill-without-query (car processes))))
1939 (process-kill-without-query (car processes) val)
1940 val)
1941 (setq active t))
1942 (setq processes (cdr processes)))
1943 (or (not active)
1944 (yes-or-no-p "Active processes exist; kill them and exit anyway? "))))
1945 (kill-emacs)))
1946 \f
1947 (define-key ctl-x-map "\C-f" 'find-file)
1948 (define-key ctl-x-map "\C-q" 'toggle-read-only)
1949 (define-key ctl-x-map "\C-r" 'find-file-read-only)
1950 (define-key ctl-x-map "\C-v" 'find-alternate-file)
1951 (define-key ctl-x-map "\C-s" 'save-buffer)
1952 (define-key ctl-x-map "s" 'save-some-buffers)
1953 (define-key ctl-x-map "\C-w" 'write-file)
1954 (define-key ctl-x-map "i" 'insert-file)
1955 (define-key esc-map "~" 'not-modified)
1956 (define-key ctl-x-map "\C-d" 'list-directory)
1957 (define-key ctl-x-map "\C-c" 'save-buffers-kill-emacs)
1958
1959 (define-key ctl-x-4-map "f" 'find-file-other-window)
1960 (define-key ctl-x-4-map "r" 'find-file-read-only-other-window)
1961 (define-key ctl-x-4-map "\C-f" 'find-file-other-window)
1962 (define-key ctl-x-4-map "b" 'switch-to-buffer-other-window)
1963 (define-key ctl-x-4-map "\C-o" 'display-buffer)
1964
1965 (define-key ctl-x-5-map "b" 'switch-to-buffer-other-frame)
1966 (define-key ctl-x-5-map "f" 'find-file-other-frame)
1967 (define-key ctl-x-5-map "\C-f" 'find-file-other-frame)
1968 (define-key ctl-x-5-map "r" 'find-file-read-only-other-frame)
1969
1970 ;;; files.el ends here