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1 ;;; files.el --- file input and output commands for Emacs
2
3 ;; Copyright (C) 1985, 86, 87, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001, 2002
4 ;;; Free Software Foundation, Inc.
5
6 ;; Maintainer: FSF
7
8 ;; This file is part of GNU Emacs.
9
10 ;; GNU Emacs is free software; you can redistribute it and/or modify
11 ;; it under the terms of the GNU General Public License as published by
12 ;; the Free Software Foundation; either version 2, or (at your option)
13 ;; any later version.
14
15 ;; GNU Emacs is distributed in the hope that it will be useful,
16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 ;; GNU General Public License for more details.
19
20 ;; You should have received a copy of the GNU General Public License
21 ;; along with GNU Emacs; see the file COPYING. If not, write to the
22 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 ;; Boston, MA 02111-1307, USA.
24
25 ;;; Commentary:
26
27 ;; Defines most of Emacs's file- and directory-handling functions,
28 ;; including basic file visiting, backup generation, link handling,
29 ;; ITS-id version control, load- and write-hook handling, and the like.
30
31 ;;; Code:
32
33 (defgroup backup nil
34 "Backups of edited data files."
35 :group 'files)
36
37 (defgroup find-file nil
38 "Finding files."
39 :group 'files)
40
41
42 (defcustom delete-auto-save-files t
43 "*Non-nil means delete auto-save file when a buffer is saved or killed.
44
45 Note that auto-save file will not be deleted if the buffer is killed
46 when it has unsaved changes."
47 :type 'boolean
48 :group 'auto-save)
49
50 (defcustom directory-abbrev-alist
51 nil
52 "*Alist of abbreviations for file directories.
53 A list of elements of the form (FROM . TO), each meaning to replace
54 FROM with TO when it appears in a directory name. This replacement is
55 done when setting up the default directory of a newly visited file.
56 *Every* FROM string should start with `^'.
57
58 Do not use `~' in the TO strings.
59 They should be ordinary absolute directory names.
60
61 Use this feature when you have directories which you normally refer to
62 via absolute symbolic links. Make TO the name of the link, and FROM
63 the name it is linked to."
64 :type '(repeat (cons :format "%v"
65 :value ("" . "")
66 (regexp :tag "From")
67 (regexp :tag "To")))
68 :group 'abbrev
69 :group 'find-file)
70
71 ;; Turn off backup files on VMS since it has version numbers.
72 (defcustom make-backup-files (not (eq system-type 'vax-vms))
73 "*Non-nil means make a backup of a file the first time it is saved.
74 This can be done by renaming the file or by copying.
75
76 Renaming means that Emacs renames the existing file so that it is a
77 backup file, then writes the buffer into a new file. Any other names
78 that the old file had will now refer to the backup file. The new file
79 is owned by you and its group is defaulted.
80
81 Copying means that Emacs copies the existing file into the backup
82 file, then writes the buffer on top of the existing file. Any other
83 names that the old file had will now refer to the new (edited) file.
84 The file's owner and group are unchanged.
85
86 The choice of renaming or copying is controlled by the variables
87 `backup-by-copying', `backup-by-copying-when-linked',
88 `backup-by-copying-when-mismatch' and
89 `backup-by-copying-when-privileged-mismatch'. See also `backup-inhibited'."
90 :type 'boolean
91 :group 'backup)
92
93 ;; Do this so that local variables based on the file name
94 ;; are not overridden by the major mode.
95 (defvar backup-inhibited nil
96 "Non-nil means don't make a backup, regardless of the other parameters.
97 This variable is intended for use by making it local to a buffer.
98 But it is local only if you make it local.")
99 (put 'backup-inhibited 'permanent-local t)
100
101 (defcustom backup-by-copying nil
102 "*Non-nil means always use copying to create backup files.
103 See documentation of variable `make-backup-files'."
104 :type 'boolean
105 :group 'backup)
106
107 (defcustom backup-by-copying-when-linked nil
108 "*Non-nil means use copying to create backups for files with multiple names.
109 This causes the alternate names to refer to the latest version as edited.
110 This variable is relevant only if `backup-by-copying' is nil."
111 :type 'boolean
112 :group 'backup)
113
114 (defcustom backup-by-copying-when-mismatch nil
115 "*Non-nil means create backups by copying if this preserves owner or group.
116 Renaming may still be used (subject to control of other variables)
117 when it would not result in changing the owner or group of the file;
118 that is, for files which are owned by you and whose group matches
119 the default for a new file created there by you.
120 This variable is relevant only if `backup-by-copying' is nil."
121 :type 'boolean
122 :group 'backup)
123
124 (defcustom backup-by-copying-when-privileged-mismatch 200
125 "*Non-nil means create backups by copying to preserve a privileged owner.
126 Renaming may still be used (subject to control of other variables)
127 when it would not result in changing the owner of the file or if the owner
128 has a user id greater than the value of this variable. This is useful
129 when low-numbered uid's are used for special system users (such as root)
130 that must maintain ownership of certain files.
131 This variable is relevant only if `backup-by-copying' and
132 `backup-by-copying-when-mismatch' are nil."
133 :type '(choice (const nil) integer)
134 :group 'backup)
135
136 (defvar backup-enable-predicate 'normal-backup-enable-predicate
137 "Predicate that looks at a file name and decides whether to make backups.
138 Called with an absolute file name as argument, it returns t to enable backup.")
139
140 (defcustom buffer-offer-save nil
141 "*Non-nil in a buffer means always offer to save buffer on exit.
142 Do so even if the buffer is not visiting a file.
143 Automatically local in all buffers."
144 :type 'boolean
145 :group 'backup)
146 (make-variable-buffer-local 'buffer-offer-save)
147
148 (defcustom find-file-existing-other-name t
149 "*Non-nil means find a file under alternative names, in existing buffers.
150 This means if any existing buffer is visiting the file you want
151 under another name, you get the existing buffer instead of a new buffer."
152 :type 'boolean
153 :group 'find-file)
154
155 (defcustom find-file-visit-truename nil
156 "*Non-nil means visit a file under its truename.
157 The truename of a file is found by chasing all links
158 both at the file level and at the levels of the containing directories."
159 :type 'boolean
160 :group 'find-file)
161
162 (defcustom revert-without-query
163 nil
164 "*Specify which files should be reverted without query.
165 The value is a list of regular expressions.
166 If the file name matches one of these regular expressions,
167 then `revert-buffer' reverts the file without querying
168 if the file has changed on disk and you have not edited the buffer."
169 :type '(repeat regexp)
170 :group 'find-file)
171
172 (defvar buffer-file-number nil
173 "The device number and file number of the file visited in the current buffer.
174 The value is a list of the form (FILENUM DEVNUM).
175 This pair of numbers uniquely identifies the file.
176 If the buffer is visiting a new file, the value is nil.")
177 (make-variable-buffer-local 'buffer-file-number)
178 (put 'buffer-file-number 'permanent-local t)
179
180 (defvar buffer-file-numbers-unique (not (memq system-type '(windows-nt)))
181 "Non-nil means that buffer-file-number uniquely identifies files.")
182
183 (defvar buffer-file-read-only nil
184 "Non-nil if visited file was read-only when visited.")
185 (make-variable-buffer-local 'buffer-file-read-only)
186
187 (defcustom temporary-file-directory
188 (file-name-as-directory
189 (cond ((memq system-type '(ms-dos windows-nt))
190 (or (getenv "TEMP") (getenv "TMPDIR") (getenv "TMP") "c:/temp"))
191 ((memq system-type '(vax-vms axp-vms))
192 (or (getenv "TMPDIR") (getenv "TMP") (getenv "TEMP") "SYS$SCRATCH:"))
193 (t
194 (or (getenv "TMPDIR") (getenv "TMP") (getenv "TEMP") "/tmp"))))
195 "The directory for writing temporary files."
196 :group 'files
197 :type 'directory)
198
199 (defcustom small-temporary-file-directory
200 (if (eq system-type 'ms-dos) (getenv "TMPDIR"))
201 "The directory for writing small temporary files.
202 If non-nil, this directory is used instead of `temporary-file-directory'
203 by programs that create small temporary files. This is for systems that
204 have fast storage with limited space, such as a RAM disk."
205 :group 'files
206 :type '(choice (const nil) directory))
207
208 ;; The system null device. (Should reference NULL_DEVICE from C.)
209 (defvar null-device "/dev/null" "The system null device.")
210
211 (defvar file-name-invalid-regexp
212 (cond ((and (eq system-type 'ms-dos) (not (msdos-long-file-names)))
213 (concat "^\\([^A-Z[-`a-z]\\|..+\\)?:\\|" ; colon except after drive
214 "[+, ;=|<>\"?*]\\|\\[\\|\\]\\|" ; invalid characters
215 "[\000-\031]\\|" ; control characters
216 "\\(/\\.\\.?[^/]\\)\\|" ; leading dots
217 "\\(/[^/.]+\\.[^/.]*\\.\\)")) ; more than a single dot
218 ((memq system-type '(ms-dos windows-nt cygwin))
219 (concat "^\\([^A-Z[-`a-z]\\|..+\\)?:\\|" ; colon except after drive
220 "[|<>\"?*\000-\031]")) ; invalid characters
221 (t "[\000]"))
222 "Regexp recognizing file names which aren't allowed by the filesystem.")
223
224 (defcustom file-precious-flag nil
225 "*Non-nil means protect against I/O errors while saving files.
226 Some modes set this non-nil in particular buffers.
227
228 This feature works by writing the new contents into a temporary file
229 and then renaming the temporary file to replace the original.
230 In this way, any I/O error in writing leaves the original untouched,
231 and there is never any instant where the file is nonexistent.
232
233 Note that this feature forces backups to be made by copying.
234 Yet, at the same time, saving a precious file
235 breaks any hard links between it and other files."
236 :type 'boolean
237 :group 'backup)
238
239 (defcustom version-control nil
240 "*Control use of version numbers for backup files.
241 t means make numeric backup versions unconditionally.
242 nil means make them for files that have some already.
243 `never' means do not make them."
244 :type '(choice (const :tag "Never" never)
245 (const :tag "If existing" nil)
246 (other :tag "Always" t))
247 :group 'backup
248 :group 'vc)
249
250 (defcustom dired-kept-versions 2
251 "*When cleaning directory, number of versions to keep."
252 :type 'integer
253 :group 'backup
254 :group 'dired)
255
256 (defcustom delete-old-versions nil
257 "*If t, delete excess backup versions silently.
258 If nil, ask confirmation. Any other value prevents any trimming."
259 :type '(choice (const :tag "Delete" t)
260 (const :tag "Ask" nil)
261 (other :tag "Leave" other))
262 :group 'backup)
263
264 (defcustom kept-old-versions 2
265 "*Number of oldest versions to keep when a new numbered backup is made."
266 :type 'integer
267 :group 'backup)
268
269 (defcustom kept-new-versions 2
270 "*Number of newest versions to keep when a new numbered backup is made.
271 Includes the new backup. Must be > 0"
272 :type 'integer
273 :group 'backup)
274
275 (defcustom require-final-newline nil
276 "*Value of t says silently ensure a file ends in a newline when it is saved.
277 Non-nil but not t says ask user whether to add a newline when there isn't one.
278 nil means don't add newlines."
279 :type '(choice (const :tag "Off" nil)
280 (const :tag "Add" t)
281 (other :tag "Ask" ask))
282 :group 'editing-basics)
283
284 (defcustom auto-save-default t
285 "*Non-nil says by default do auto-saving of every file-visiting buffer."
286 :type 'boolean
287 :group 'auto-save)
288
289 (defcustom auto-save-visited-file-name nil
290 "*Non-nil says auto-save a buffer in the file it is visiting, when practical.
291 Normally auto-save files are written under other names."
292 :type 'boolean
293 :group 'auto-save)
294
295 (defcustom auto-save-file-name-transforms
296 `(("\\`/[^/]*:\\(.+/\\)*\\(.*\\)"
297 ;; Don't put "\\2" inside expand-file-name, since it will be
298 ;; transformed to "/2" on DOS/Windows.
299 ,(concat temporary-file-directory "\\2") t))
300 "*Transforms to apply to buffer file name before making auto-save file name.
301 Each transform is a list (REGEXP REPLACEMENT UNIQUIFY):
302 REGEXP is a regular expression to match against the file name.
303 If it matches, `replace-match' is used to replace the
304 matching part with REPLACEMENT.
305 If the optional element UNIQUIFY is non-nil, the auto-save file name is
306 constructed by taking the directory part of the replaced file-name,
307 concatenated with the buffer file name with all directory separators
308 changed to `!' to prevent clashes. This will not work
309 correctly if your filesystem truncates the resulting name.
310
311 All the transforms in the list are tried, in the order they are listed.
312 When one transform applies, its result is final;
313 no further transforms are tried.
314
315 The default value is set up to put the auto-save file into the
316 temporary directory (see the variable `temporary-file-directory') for
317 editing a remote file.
318
319 On MS-DOS filesystems without long names this variable is always
320 ignored."
321 :group 'auto-save
322 :type '(repeat (list (string :tag "Regexp") (string :tag "Replacement")
323 (boolean :tag "Uniquify")))
324 :version "21.1")
325
326 (defcustom save-abbrevs t
327 "*Non-nil means save word abbrevs too when files are saved.
328 If `silently', don't ask the user before saving."
329 :type '(choice (const t) (const nil) (const silently))
330 :group 'abbrev)
331
332 (defcustom find-file-run-dired t
333 "*Non-nil means allow `find-file' to visit directories.
334 To visit the directory, `find-file' runs `find-directory-functions'."
335 :type 'boolean
336 :group 'find-file)
337
338 (defcustom find-directory-functions '(cvs-dired-noselect dired-noselect)
339 "*List of functions to try in sequence to visit a directory.
340 Each function is called with the directory name as the sole argument
341 and should return either a buffer or nil."
342 :type '(hook :options (cvs-dired-noselect dired-noselect))
343 :group 'find-file)
344
345 ;;;It is not useful to make this a local variable.
346 ;;;(put 'find-file-not-found-hooks 'permanent-local t)
347 (defvar find-file-not-found-functions nil
348 "List of functions to be called for `find-file' on nonexistent file.
349 These functions are called as soon as the error is detected.
350 Variable `buffer-file-name' is already set up.
351 The functions are called in the order given until one of them returns non-nil.")
352 (defvaralias 'find-file-not-found-hooks 'find-file-not-found-functions)
353 (make-obsolete-variable
354 'find-file-not-found-hooks 'find-file-not-found-functions "21.4")
355
356 ;;;It is not useful to make this a local variable.
357 ;;;(put 'find-file-hooks 'permanent-local t)
358 (defvar find-file-hook nil
359 "List of functions to be called after a buffer is loaded from a file.
360 The buffer's local variables (if any) will have been processed before the
361 functions are called.")
362 (defvaralias 'find-file-hooks 'find-file-hook)
363 (make-obsolete-variable 'find-file-hooks 'find-file-hook "21.4")
364
365 (defvar write-file-functions nil
366 "List of functions to be called before writing out a buffer to a file.
367 If one of them returns non-nil, the file is considered already written
368 and the rest are not called.
369 These hooks are considered to pertain to the visited file.
370 So any buffer-local binding of this variable is discarded if you change
371 the visited file name with \\[set-visited-file-name], but not when you
372 change the major mode.
373
374 See also `write-contents-functions'.")
375 (put 'write-file-functions 'permanent-local t)
376 (defvaralias 'write-file-hooks 'write-file-functions)
377 (make-obsolete-variable 'write-file-hooks 'write-file-functions "21.4")
378
379 (defvar local-write-file-hooks nil)
380 (make-variable-buffer-local 'local-write-file-hooks)
381 (put 'local-write-file-hooks 'permanent-local t)
382 (make-obsolete-variable 'local-write-file-hooks 'write-file-functions "21.4")
383
384 (defvar write-contents-functions nil
385 "List of functions to be called before writing out a buffer to a file.
386 If one of them returns non-nil, the file is considered already written
387 and the rest are not called.
388
389 This variable is meant to be used for hooks that pertain to the
390 buffer's contents, not to the particular visited file; thus,
391 `set-visited-file-name' does not clear this variable; but changing the
392 major mode does clear it.
393
394 See also `write-file-functions'.")
395 (make-variable-buffer-local 'write-contents-functions)
396 (defvaralias 'write-contents-hooks 'write-contents-functions)
397 (make-obsolete-variable 'write-contents-hooks 'write-contents-functions "21.4")
398
399 (defcustom enable-local-variables t
400 "*Control use of local variables in files you visit.
401 The value can be t, nil or something else.
402 A value of t means file local variables specifications are obeyed;
403 nil means they are ignored; anything else means query.
404 This variable also controls use of major modes specified in
405 a -*- line.
406
407 The command \\[normal-mode], when used interactively,
408 always obeys file local variable specifications and the -*- line,
409 and ignores this variable."
410 :type '(choice (const :tag "Obey" t)
411 (const :tag "Ignore" nil)
412 (other :tag "Query" other))
413 :group 'find-file)
414
415 (defvar local-enable-local-variables t
416 "Like `enable-local-variables' but meant for buffer-local bindings.
417 The meaningful values are nil and non-nil. The default is non-nil.
418 If a major mode sets this to nil, buffer-locally, then any local
419 variables list in the file will be ignored.
420
421 This variable does not affect the use of major modes
422 specified in a -*- line.")
423
424 (defcustom enable-local-eval 'maybe
425 "*Control processing of the \"variable\" `eval' in a file's local variables.
426 The value can be t, nil or something else.
427 A value of t means obey `eval' variables;
428 nil means ignore them; anything else means query.
429
430 The command \\[normal-mode] always obeys local-variables lists
431 and ignores this variable."
432 :type '(choice (const :tag "Obey" t)
433 (const :tag "Ignore" nil)
434 (other :tag "Query" other))
435 :group 'find-file)
436
437 ;; Avoid losing in versions where CLASH_DETECTION is disabled.
438 (or (fboundp 'lock-buffer)
439 (defalias 'lock-buffer 'ignore))
440 (or (fboundp 'unlock-buffer)
441 (defalias 'unlock-buffer 'ignore))
442 (or (fboundp 'file-locked-p)
443 (defalias 'file-locked-p 'ignore))
444
445 (defvar view-read-only nil
446 "*Non-nil means buffers visiting files read-only, do it in view mode.")
447
448 (put 'ange-ftp-completion-hook-function 'safe-magic t)
449 (defun ange-ftp-completion-hook-function (op &rest args)
450 "Provides support for ange-ftp host name completion.
451 Runs the usual ange-ftp hook, but only for completion operations."
452 ;; Having this here avoids the need to load ange-ftp when it's not
453 ;; really in use.
454 (if (memq op '(file-name-completion file-name-all-completions))
455 (apply 'ange-ftp-hook-function op args)
456 (let ((inhibit-file-name-handlers
457 (cons 'ange-ftp-completion-hook-function
458 (and (eq inhibit-file-name-operation op)
459 inhibit-file-name-handlers)))
460 (inhibit-file-name-operation op))
461 (apply op args))))
462
463 (defun convert-standard-filename (filename)
464 "Convert a standard file's name to something suitable for the current OS.
465 This function's standard definition is trivial; it just returns the argument.
466 However, on some systems, the function is redefined with a definition
467 that really does change some file names to canonicalize certain
468 patterns and to guarantee valid names."
469 filename)
470
471 (defun read-directory-name (prompt &optional dir default-dirname mustmatch initial)
472 "Read directory name, prompting with PROMPT and completing in directory DIR.
473 Value is not expanded---you must call `expand-file-name' yourself.
474 Default name to DEFAULT-DIRNAME if user enters a null string.
475 (If DEFAULT-DIRNAME is omitted, the current buffer's directory is used,
476 except that if INITIAL is specified, that combined with DIR is used.)
477 Fourth arg MUSTMATCH non-nil means require existing directory's name.
478 Non-nil and non-t means also require confirmation after completion.
479 Fifth arg INITIAL specifies text to start with.
480 DIR defaults to current buffer's directory default."
481 (unless dir
482 (setq dir default-directory))
483 (unless default-dirname
484 (setq default-dirname
485 (if initial (concat dir initial) default-directory)))
486 (read-file-name prompt dir default-dirname mustmatch initial
487 'file-directory-p))
488
489 \f
490 (defun pwd ()
491 "Show the current default directory."
492 (interactive nil)
493 (message "Directory %s" default-directory))
494
495 (defvar cd-path nil
496 "Value of the CDPATH environment variable, as a list.
497 Not actually set up until the first time you use it.")
498
499 (defun parse-colon-path (cd-path)
500 "Explode a colon-separated search path into a list of directory names.
501 \(For values of `colon' equal to `path-separator'.)"
502 ;; We could use split-string here.
503 (and cd-path
504 (let (cd-prefix cd-list (cd-start 0) cd-colon)
505 (setq cd-path (concat cd-path path-separator))
506 (while (setq cd-colon (string-match path-separator cd-path cd-start))
507 (setq cd-list
508 (nconc cd-list
509 (list (if (= cd-start cd-colon)
510 nil
511 (substitute-in-file-name
512 (file-name-as-directory
513 (substring cd-path cd-start cd-colon)))))))
514 (setq cd-start (+ cd-colon 1)))
515 cd-list)))
516
517 (defun cd-absolute (dir)
518 "Change current directory to given absolute file name DIR."
519 ;; Put the name into directory syntax now,
520 ;; because otherwise expand-file-name may give some bad results.
521 (if (not (eq system-type 'vax-vms))
522 (setq dir (file-name-as-directory dir)))
523 (setq dir (abbreviate-file-name (expand-file-name dir)))
524 (if (not (file-directory-p dir))
525 (if (file-exists-p dir)
526 (error "%s is not a directory" dir)
527 (error "%s: no such directory" dir))
528 (if (file-executable-p dir)
529 (setq default-directory dir)
530 (error "Cannot cd to %s: Permission denied" dir))))
531
532 (defun cd (dir)
533 "Make DIR become the current buffer's default directory.
534 If your environment includes a `CDPATH' variable, try each one of that
535 colon-separated list of directories when resolving a relative directory name."
536 (interactive
537 (list (read-directory-name "Change default directory: "
538 default-directory default-directory
539 (and (member cd-path '(nil ("./")))
540 (null (getenv "CDPATH"))))))
541 (if (file-name-absolute-p dir)
542 (cd-absolute (expand-file-name dir))
543 (if (null cd-path)
544 (let ((trypath (parse-colon-path (getenv "CDPATH"))))
545 (setq cd-path (or trypath (list "./")))))
546 (if (not (catch 'found
547 (mapcar
548 (function (lambda (x)
549 (let ((f (expand-file-name (concat x dir))))
550 (if (file-directory-p f)
551 (progn
552 (cd-absolute f)
553 (throw 'found t))))))
554 cd-path)
555 nil))
556 (error "No such directory found via CDPATH environment variable"))))
557
558 (defun load-file (file)
559 "Load the Lisp file named FILE."
560 ;; This is a case where .elc makes a lot of sense.
561 (interactive (list (let ((completion-ignored-extensions
562 (remove ".elc" completion-ignored-extensions)))
563 (read-file-name "Load file: "))))
564 (load (expand-file-name file) nil nil t))
565
566 (defun locate-file (filename path &optional suffixes predicate)
567 "Search for FILENAME through PATH.
568 If SUFFIXES is non-nil, it should be a list of suffixes to append to
569 file name when searching. If SUFFIXES is nil, it is equivalent to '(\"\").
570 If non-nil, PREDICATE is used instead of `file-readable-p'.
571 PREDICATE can also be an integer to pass to the `access' system call,
572 in which case file-name handlers are ignored. This usage is deprecated.
573
574 For compatibility, PREDICATE can also be one of the symbols
575 `executable', `readable', `writable', or `exists', or a list of
576 one or more of those symbols."
577 (if (and predicate (symbolp predicate) (not (functionp predicate)))
578 (setq predicate (list predicate)))
579 (when (and (consp predicate) (not (functionp predicate)))
580 (setq predicate
581 (logior (if (memq 'executable predicate) 1 0)
582 (if (memq 'writable predicate) 2 0)
583 (if (memq 'readable predicate) 4 0))))
584 (locate-file-internal filename path suffixes predicate))
585
586 (defun locate-file-completion (string path-and-suffixes action)
587 "Do completion for file names passed to `locate-file'.
588 PATH-AND-SUFFIXES is a pair of lists (DIRECTORIES . SUFFIXES)."
589 (if (file-name-absolute-p string)
590 (read-file-name-internal string nil action)
591 (let ((names nil)
592 (suffix (concat (regexp-opt (cdr path-and-suffixes) t) "\\'"))
593 (string-dir (file-name-directory string)))
594 (dolist (dir (car path-and-suffixes))
595 (if string-dir (setq dir (expand-file-name string-dir dir)))
596 (when (file-directory-p dir)
597 (dolist (file (file-name-all-completions
598 (file-name-nondirectory string) dir))
599 (push (if string-dir (concat string-dir file) file) names)
600 (when (string-match suffix file)
601 (setq file (substring file 0 (match-beginning 0)))
602 (push (if string-dir (concat string-dir file) file) names)))))
603 (cond
604 ((eq action t) (all-completions string names))
605 ((null action) (try-completion string names))
606 (t (test-completion string names))))))
607
608 (defun load-library (library)
609 "Load the library named LIBRARY.
610 This is an interface to the function `load'."
611 (interactive
612 (list (completing-read "Load library: "
613 'locate-file-completion
614 (cons load-path load-suffixes))))
615 (load library))
616
617 (defun file-remote-p (file)
618 "Test whether FILE specifies a location on a remote system."
619 (let ((handler (find-file-name-handler file 'file-local-copy)))
620 (if handler
621 (get handler 'file-remote-p))))
622
623 (defun file-local-copy (file)
624 "Copy the file FILE into a temporary file on this machine.
625 Returns the name of the local copy, or nil, if FILE is directly
626 accessible."
627 ;; This formerly had an optional BUFFER argument that wasn't used by
628 ;; anything.
629 (let ((handler (find-file-name-handler file 'file-local-copy)))
630 (if handler
631 (funcall handler 'file-local-copy file)
632 nil)))
633
634 (defun file-truename (filename &optional counter prev-dirs)
635 "Return the truename of FILENAME, which should be absolute.
636 The truename of a file name is found by chasing symbolic links
637 both at the level of the file and at the level of the directories
638 containing it, until no links are left at any level.
639
640 The arguments COUNTER and PREV-DIRS are used only in recursive calls.
641 Do not specify them in other calls."
642 ;; COUNTER can be a cons cell whose car is the count of how many more links
643 ;; to chase before getting an error.
644 ;; PREV-DIRS can be a cons cell whose car is an alist
645 ;; of truenames we've just recently computed.
646
647 ;; The last test looks dubious, maybe `+' is meant here? --simon.
648 (if (or (string= filename "") (string= filename "~")
649 (and (string= (substring filename 0 1) "~")
650 (string-match "~[^/]*" filename)))
651 (progn
652 (setq filename (expand-file-name filename))
653 (if (string= filename "")
654 (setq filename "/"))))
655 (or counter (setq counter (list 100)))
656 (let (done
657 ;; For speed, remove the ange-ftp completion handler from the list.
658 ;; We know it's not needed here.
659 ;; For even more speed, do this only on the outermost call.
660 (file-name-handler-alist
661 (if prev-dirs file-name-handler-alist
662 (let ((tem (copy-sequence file-name-handler-alist)))
663 (delq (rassq 'ange-ftp-completion-hook-function tem) tem)))))
664 (or prev-dirs (setq prev-dirs (list nil)))
665
666 ;; andrewi@harlequin.co.uk - none of the following code (except for
667 ;; invoking the file-name handler) currently applies on Windows
668 ;; (ie. there are no native symlinks), but there is an issue with
669 ;; case differences being ignored by the OS, and short "8.3 DOS"
670 ;; name aliases existing for all files. (The short names are not
671 ;; reported by directory-files, but can be used to refer to files.)
672 ;; It seems appropriate for file-truename to resolve these issues in
673 ;; the most natural way, which on Windows is to call the function
674 ;; `w32-long-file-name' - this returns the exact name of a file as
675 ;; it is stored on disk (expanding short name aliases with the full
676 ;; name in the process).
677 (if (eq system-type 'windows-nt)
678 (let ((handler (find-file-name-handler filename 'file-truename)))
679 ;; For file name that has a special handler, call handler.
680 ;; This is so that ange-ftp can save time by doing a no-op.
681 (if handler
682 (setq filename (funcall handler 'file-truename filename))
683 ;; If filename contains a wildcard, newname will be the old name.
684 (unless (string-match "[[*?]" filename)
685 ;; If filename exists, use the long name, otherwise
686 ;; canonicalize the name, to handle case differences.
687 (setq filename (or (w32-long-file-name filename)
688 (untranslated-canonical-name filename)))))
689 (setq done t)))
690
691 ;; If this file directly leads to a link, process that iteratively
692 ;; so that we don't use lots of stack.
693 (while (not done)
694 (setcar counter (1- (car counter)))
695 (if (< (car counter) 0)
696 (error "Apparent cycle of symbolic links for %s" filename))
697 (let ((handler (find-file-name-handler filename 'file-truename)))
698 ;; For file name that has a special handler, call handler.
699 ;; This is so that ange-ftp can save time by doing a no-op.
700 (if handler
701 (setq filename (funcall handler 'file-truename filename)
702 done t)
703 (let ((dir (or (file-name-directory filename) default-directory))
704 target dirfile)
705 ;; Get the truename of the directory.
706 (setq dirfile (directory-file-name dir))
707 ;; If these are equal, we have the (or a) root directory.
708 (or (string= dir dirfile)
709 ;; If this is the same dir we last got the truename for,
710 ;; save time--don't recalculate.
711 (if (assoc dir (car prev-dirs))
712 (setq dir (cdr (assoc dir (car prev-dirs))))
713 (let ((old dir)
714 (new (file-name-as-directory (file-truename dirfile counter prev-dirs))))
715 (setcar prev-dirs (cons (cons old new) (car prev-dirs)))
716 (setq dir new))))
717 (if (equal ".." (file-name-nondirectory filename))
718 (setq filename
719 (directory-file-name (file-name-directory (directory-file-name dir)))
720 done t)
721 (if (equal "." (file-name-nondirectory filename))
722 (setq filename (directory-file-name dir)
723 done t)
724 ;; Put it back on the file name.
725 (setq filename (concat dir (file-name-nondirectory filename)))
726 ;; Is the file name the name of a link?
727 (setq target (file-symlink-p filename))
728 (if target
729 ;; Yes => chase that link, then start all over
730 ;; since the link may point to a directory name that uses links.
731 ;; We can't safely use expand-file-name here
732 ;; since target might look like foo/../bar where foo
733 ;; is itself a link. Instead, we handle . and .. above.
734 (setq filename
735 (if (file-name-absolute-p target)
736 target
737 (concat dir target))
738 done nil)
739 ;; No, we are done!
740 (setq done t))))))))
741 filename))
742
743 (defun file-chase-links (filename)
744 "Chase links in FILENAME until a name that is not a link.
745 Does not examine containing directories for links,
746 unlike `file-truename'."
747 (let (tem (count 100) (newname filename))
748 (while (setq tem (file-symlink-p newname))
749 (save-match-data
750 (if (= count 0)
751 (error "Apparent cycle of symbolic links for %s" filename))
752 ;; In the context of a link, `//' doesn't mean what Emacs thinks.
753 (while (string-match "//+" tem)
754 (setq tem (replace-match "/" nil nil tem)))
755 ;; Handle `..' by hand, since it needs to work in the
756 ;; target of any directory symlink.
757 ;; This code is not quite complete; it does not handle
758 ;; embedded .. in some cases such as ./../foo and foo/bar/../../../lose.
759 (while (string-match "\\`\\.\\./" tem)
760 (setq tem (substring tem 3))
761 (setq newname (expand-file-name newname))
762 ;; Chase links in the default dir of the symlink.
763 (setq newname
764 (file-chase-links
765 (directory-file-name (file-name-directory newname))))
766 ;; Now find the parent of that dir.
767 (setq newname (file-name-directory newname)))
768 (setq newname (expand-file-name tem (file-name-directory newname)))
769 (setq count (1- count))))
770 newname))
771 \f
772 (defun switch-to-buffer-other-window (buffer &optional norecord)
773 "Select buffer BUFFER in another window.
774 Optional second arg NORECORD non-nil means
775 do not put this buffer at the front of the list of recently selected ones.
776
777 This uses the function `display-buffer' as a subroutine; see its
778 documentation for additional customization information."
779 (interactive "BSwitch to buffer in other window: ")
780 (let ((pop-up-windows t))
781 (pop-to-buffer buffer t norecord)))
782
783 (defun switch-to-buffer-other-frame (buffer &optional norecord)
784 "Switch to buffer BUFFER in another frame.
785 Optional second arg NORECORD non-nil means
786 do not put this buffer at the front of the list of recently selected ones.
787
788 This uses the function `display-buffer' as a subroutine; see its
789 documentation for additional customization information."
790 (interactive "BSwitch to buffer in other frame: ")
791 (let ((pop-up-frames t))
792 (pop-to-buffer buffer t norecord)
793 (raise-frame (window-frame (selected-window)))))
794
795 (defvar find-file-default nil
796 "Used within `find-file-read-args'.")
797
798 (defun find-file-read-args (prompt mustmatch)
799 (list (let ((find-file-default
800 (and buffer-file-name
801 (abbreviate-file-name buffer-file-name)))
802 (munge-default-fun
803 (lambda ()
804 (setq minibuffer-default find-file-default)
805 ;; Clear out this hook so it does not interfere
806 ;; with any recursive minibuffer usage.
807 (pop minibuffer-setup-hook)))
808 (minibuffer-setup-hook
809 minibuffer-setup-hook))
810 (add-hook 'minibuffer-setup-hook munge-default-fun)
811 (read-file-name prompt nil default-directory mustmatch))
812 t))
813
814 (defun find-file (filename &optional wildcards)
815 "Edit file FILENAME.
816 Switch to a buffer visiting file FILENAME,
817 creating one if none already exists.
818 Interactively, the default if you just type RET is the current directory,
819 but the visited file name is available through the minibuffer history:
820 type M-n to pull it into the minibuffer.
821
822 Interactively, or if WILDCARDS is non-nil in a call from Lisp,
823 expand wildcards (if any) and visit multiple files. Wildcard expansion
824 can be suppressed by setting `find-file-wildcards'."
825 (interactive
826 (find-file-read-args "Find file: " nil))
827 (let ((value (find-file-noselect filename nil nil wildcards)))
828 (if (listp value)
829 (mapcar 'switch-to-buffer (nreverse value))
830 (switch-to-buffer value))))
831
832 (defun find-file-other-window (filename &optional wildcards)
833 "Edit file FILENAME, in another window.
834 May create a new window, or reuse an existing one.
835 See the function `display-buffer'.
836
837 Interactively, the default if you just type RET is the current directory,
838 but the visited file name is available through the minibuffer history:
839 type M-n to pull it into the minibuffer.
840
841 Interactively, or if WILDCARDS is non-nil in a call from Lisp,
842 expand wildcards (if any) and visit multiple files."
843 (interactive (find-file-read-args "Find file in other window: " nil))
844 (let ((value (find-file-noselect filename nil nil wildcards)))
845 (if (listp value)
846 (progn
847 (setq value (nreverse value))
848 (switch-to-buffer-other-window (car value))
849 (mapcar 'switch-to-buffer (cdr value)))
850 (switch-to-buffer-other-window value))))
851
852 (defun find-file-other-frame (filename &optional wildcards)
853 "Edit file FILENAME, in another frame.
854 May create a new frame, or reuse an existing one.
855 See the function `display-buffer'.
856
857 Interactively, the default if you just type RET is the current directory,
858 but the visited file name is available through the minibuffer history:
859 type M-n to pull it into the minibuffer.
860
861 Interactively, or if WILDCARDS is non-nil in a call from Lisp,
862 expand wildcards (if any) and visit multiple files."
863 (interactive (find-file-read-args "Find file in other frame: " nil))
864 (let ((value (find-file-noselect filename nil nil wildcards)))
865 (if (listp value)
866 (progn
867 (setq value (nreverse value))
868 (switch-to-buffer-other-frame (car value))
869 (mapcar 'switch-to-buffer (cdr value)))
870 (switch-to-buffer-other-frame value))))
871
872 (defun find-file-read-only (filename &optional wildcards)
873 "Edit file FILENAME but don't allow changes.
874 Like \\[find-file] but marks buffer as read-only.
875 Use \\[toggle-read-only] to permit editing."
876 (interactive (find-file-read-args "Find file read-only: " t))
877 (find-file filename wildcards)
878 (toggle-read-only 1)
879 (current-buffer))
880
881 (defun find-file-read-only-other-window (filename &optional wildcards)
882 "Edit file FILENAME in another window but don't allow changes.
883 Like \\[find-file-other-window] but marks buffer as read-only.
884 Use \\[toggle-read-only] to permit editing."
885 (interactive (find-file-read-args "Find file read-only other window: " t))
886 (find-file-other-window filename wildcards)
887 (toggle-read-only 1)
888 (current-buffer))
889
890 (defun find-file-read-only-other-frame (filename &optional wildcards)
891 "Edit file FILENAME in another frame but don't allow changes.
892 Like \\[find-file-other-frame] but marks buffer as read-only.
893 Use \\[toggle-read-only] to permit editing."
894 (interactive (find-file-read-args "Find file read-only other frame: " t))
895 (find-file-other-frame filename wildcards)
896 (toggle-read-only 1)
897 (current-buffer))
898
899 (defun find-alternate-file-other-window (filename)
900 "Find file FILENAME as a replacement for the file in the next window.
901 This command does not select that window."
902 (interactive
903 (save-selected-window
904 (other-window 1)
905 (let ((file buffer-file-name)
906 (file-name nil)
907 (file-dir nil))
908 (and file
909 (setq file-name (file-name-nondirectory file)
910 file-dir (file-name-directory file)))
911 (list (read-file-name
912 "Find alternate file: " file-dir nil nil file-name)))))
913 (if (one-window-p)
914 (find-file-other-window filename)
915 (save-selected-window
916 (other-window 1)
917 (find-alternate-file filename))))
918
919 (defun find-alternate-file (filename)
920 "Find file FILENAME, select its buffer, kill previous buffer.
921 If the current buffer now contains an empty file that you just visited
922 \(presumably by mistake), use this command to visit the file you really want."
923 (interactive
924 (let ((file buffer-file-name)
925 (file-name nil)
926 (file-dir nil))
927 (and file
928 (setq file-name (file-name-nondirectory file)
929 file-dir (file-name-directory file)))
930 (list (read-file-name
931 "Find alternate file: " file-dir nil nil file-name))))
932 (unless (run-hook-with-args-until-failure 'kill-buffer-query-functions)
933 (error "Aborted"))
934 (when (and (buffer-modified-p) (buffer-file-name))
935 (if (yes-or-no-p (format "Buffer %s is modified; save it first? "
936 (buffer-name)))
937 (save-buffer)
938 (unless (yes-or-no-p "Kill and replace the buffer without saving it? ")
939 (error "Aborted"))))
940 (let ((obuf (current-buffer))
941 (ofile buffer-file-name)
942 (onum buffer-file-number)
943 (odir dired-directory)
944 (otrue buffer-file-truename)
945 (oname (buffer-name)))
946 (if (get-buffer " **lose**")
947 (kill-buffer " **lose**"))
948 (rename-buffer " **lose**")
949 (unwind-protect
950 (progn
951 (unlock-buffer)
952 ;; This prevents us from finding the same buffer
953 ;; if we specified the same file again.
954 (setq buffer-file-name nil)
955 (setq buffer-file-number nil)
956 (setq buffer-file-truename nil)
957 ;; Likewise for dired buffers.
958 (setq dired-directory nil)
959 (find-file filename))
960 (when (eq obuf (current-buffer))
961 ;; This executes if find-file gets an error
962 ;; and does not really find anything.
963 ;; We put things back as they were.
964 ;; If find-file actually finds something, we kill obuf below.
965 (setq buffer-file-name ofile)
966 (setq buffer-file-number onum)
967 (setq buffer-file-truename otrue)
968 (setq dired-directory odir)
969 (lock-buffer)
970 (rename-buffer oname)))
971 (unless (eq (current-buffer) obuf)
972 (with-current-buffer obuf
973 ;; We already asked; don't ask again.
974 (let ((kill-buffer-query-functions))
975 (kill-buffer obuf))))))
976 \f
977 (defun create-file-buffer (filename)
978 "Create a suitably named buffer for visiting FILENAME, and return it.
979 FILENAME (sans directory) is used unchanged if that name is free;
980 otherwise a string <2> or <3> or ... is appended to get an unused name."
981 (let ((lastname (file-name-nondirectory filename)))
982 (if (string= lastname "")
983 (setq lastname filename))
984 (generate-new-buffer lastname)))
985
986 (defun generate-new-buffer (name)
987 "Create and return a buffer with a name based on NAME.
988 Choose the buffer's name using `generate-new-buffer-name'."
989 (get-buffer-create (generate-new-buffer-name name)))
990
991 (defcustom automount-dir-prefix "^/tmp_mnt/"
992 "Regexp to match the automounter prefix in a directory name."
993 :group 'files
994 :type 'regexp)
995
996 (defvar abbreviated-home-dir nil
997 "The user's homedir abbreviated according to `directory-abbrev-alist'.")
998
999 (defun abbreviate-file-name (filename)
1000 "Return a version of FILENAME shortened using `directory-abbrev-alist'.
1001 This also substitutes \"~\" for the user's home directory.
1002 Type \\[describe-variable] directory-abbrev-alist RET for more information."
1003 ;; Get rid of the prefixes added by the automounter.
1004 (if (and automount-dir-prefix
1005 (string-match automount-dir-prefix filename)
1006 (file-exists-p (file-name-directory
1007 (substring filename (1- (match-end 0))))))
1008 (setq filename (substring filename (1- (match-end 0)))))
1009 (let ((tail directory-abbrev-alist))
1010 ;; If any elt of directory-abbrev-alist matches this name,
1011 ;; abbreviate accordingly.
1012 (while tail
1013 (if (string-match (car (car tail)) filename)
1014 (setq filename
1015 (concat (cdr (car tail)) (substring filename (match-end 0)))))
1016 (setq tail (cdr tail)))
1017 ;; Compute and save the abbreviated homedir name.
1018 ;; We defer computing this until the first time it's needed, to
1019 ;; give time for directory-abbrev-alist to be set properly.
1020 ;; We include a slash at the end, to avoid spurious matches
1021 ;; such as `/usr/foobar' when the home dir is `/usr/foo'.
1022 (or abbreviated-home-dir
1023 (setq abbreviated-home-dir
1024 (let ((abbreviated-home-dir "$foo"))
1025 (concat "^" (abbreviate-file-name (expand-file-name "~"))
1026 "\\(/\\|$\\)"))))
1027
1028 ;; If FILENAME starts with the abbreviated homedir,
1029 ;; make it start with `~' instead.
1030 (if (and (string-match abbreviated-home-dir filename)
1031 ;; If the home dir is just /, don't change it.
1032 (not (and (= (match-end 0) 1)
1033 (= (aref filename 0) ?/)))
1034 ;; MS-DOS root directories can come with a drive letter;
1035 ;; Novell Netware allows drive letters beyond `Z:'.
1036 (not (and (or (eq system-type 'ms-dos)
1037 (eq system-type 'cygwin)
1038 (eq system-type 'windows-nt))
1039 (save-match-data
1040 (string-match "^[a-zA-`]:/$" filename)))))
1041 (setq filename
1042 (concat "~"
1043 (substring filename (match-beginning 1) (match-end 1))
1044 (substring filename (match-end 0)))))
1045 filename))
1046
1047 (defcustom find-file-not-true-dirname-list nil
1048 "*List of logical names for which visiting shouldn't save the true dirname.
1049 On VMS, when you visit a file using a logical name that searches a path,
1050 you may or may not want the visited file name to record the specific
1051 directory where the file was found. If you *do not* want that, add the logical
1052 name to this list as a string."
1053 :type '(repeat (string :tag "Name"))
1054 :group 'find-file)
1055
1056 (defun find-buffer-visiting (filename &optional predicate)
1057 "Return the buffer visiting file FILENAME (a string).
1058 This is like `get-file-buffer', except that it checks for any buffer
1059 visiting the same file, possibly under a different name.
1060 If PREDICATE is non-nil, only a buffer satisfying it can be returned.
1061 If there is no such live buffer, return nil."
1062 (let ((predicate (or predicate #'identity))
1063 (truename (abbreviate-file-name (file-truename filename))))
1064 (or (let ((buf (get-file-buffer filename)))
1065 (when (and buf (funcall predicate buf)) buf))
1066 (let ((list (buffer-list)) found)
1067 (while (and (not found) list)
1068 (save-excursion
1069 (set-buffer (car list))
1070 (if (and buffer-file-name
1071 (string= buffer-file-truename truename)
1072 (funcall predicate (current-buffer)))
1073 (setq found (car list))))
1074 (setq list (cdr list)))
1075 found)
1076 (let* ((attributes (file-attributes truename))
1077 (number (nthcdr 10 attributes))
1078 (list (buffer-list)) found)
1079 (and buffer-file-numbers-unique
1080 number
1081 (while (and (not found) list)
1082 (with-current-buffer (car list)
1083 (if (and buffer-file-name
1084 (equal buffer-file-number number)
1085 ;; Verify this buffer's file number
1086 ;; still belongs to its file.
1087 (file-exists-p buffer-file-name)
1088 (equal (file-attributes buffer-file-truename)
1089 attributes)
1090 (funcall predicate (current-buffer)))
1091 (setq found (car list))))
1092 (setq list (cdr list))))
1093 found))))
1094 \f
1095 (defcustom find-file-wildcards t
1096 "*Non-nil means file-visiting commands should handle wildcards.
1097 For example, if you specify `*.c', that would visit all the files
1098 whose names match the pattern."
1099 :group 'files
1100 :version "20.4"
1101 :type 'boolean)
1102
1103 (defcustom find-file-suppress-same-file-warnings nil
1104 "*Non-nil means suppress warning messages for symlinked files.
1105 When nil, Emacs prints a warning when visiting a file that is already
1106 visited, but with a different name. Setting this option to t
1107 suppresses this warning."
1108 :group 'files
1109 :version "21.1"
1110 :type 'boolean)
1111
1112 (defun find-file-noselect (filename &optional nowarn rawfile wildcards)
1113 "Read file FILENAME into a buffer and return the buffer.
1114 If a buffer exists visiting FILENAME, return that one, but
1115 verify that the file has not changed since visited or saved.
1116 The buffer is not selected, just returned to the caller.
1117 Optional first arg NOWARN non-nil means suppress any warning messages.
1118 Optional second arg RAWFILE non-nil means the file is read literally.
1119 Optional third arg WILDCARDS non-nil means do wildcard processing
1120 and visit all the matching files. When wildcards are actually
1121 used and expanded, the value is a list of buffers
1122 that are visiting the various files."
1123 (setq filename
1124 (abbreviate-file-name
1125 (expand-file-name filename)))
1126 (if (file-directory-p filename)
1127 (or (and find-file-run-dired
1128 (run-hook-with-args-until-success
1129 'find-directory-functions
1130 (if find-file-visit-truename
1131 (abbreviate-file-name (file-truename filename))
1132 filename)))
1133 (error "%s is a directory" filename))
1134 (if (and wildcards
1135 find-file-wildcards
1136 (not (string-match "\\`/:" filename))
1137 (string-match "[[*?]" filename))
1138 (let ((files (condition-case nil
1139 (file-expand-wildcards filename t)
1140 (error (list filename))))
1141 (find-file-wildcards nil))
1142 (if (null files)
1143 (find-file-noselect filename)
1144 (mapcar #'find-file-noselect files)))
1145 (let* ((buf (get-file-buffer filename))
1146 (truename (abbreviate-file-name (file-truename filename)))
1147 (number (nthcdr 10 (file-attributes truename)))
1148 ;; Find any buffer for a file which has same truename.
1149 (other (and (not buf) (find-buffer-visiting filename))))
1150 ;; Let user know if there is a buffer with the same truename.
1151 (if other
1152 (progn
1153 (or nowarn
1154 find-file-suppress-same-file-warnings
1155 (string-equal filename (buffer-file-name other))
1156 (message "%s and %s are the same file"
1157 filename (buffer-file-name other)))
1158 ;; Optionally also find that buffer.
1159 (if (or find-file-existing-other-name find-file-visit-truename)
1160 (setq buf other))))
1161 (if buf
1162 ;; We are using an existing buffer.
1163 (progn
1164 (or nowarn
1165 (verify-visited-file-modtime buf)
1166 (cond ((not (file-exists-p filename))
1167 (error "File %s no longer exists!" filename))
1168 ;; Certain files should be reverted automatically
1169 ;; if they have changed on disk and not in the buffer.
1170 ((and (not (buffer-modified-p buf))
1171 (let ((tail revert-without-query)
1172 (found nil))
1173 (while tail
1174 (if (string-match (car tail) filename)
1175 (setq found t))
1176 (setq tail (cdr tail)))
1177 found))
1178 (with-current-buffer buf
1179 (message "Reverting file %s..." filename)
1180 (revert-buffer t t)
1181 (message "Reverting file %s...done" filename)))
1182 ((yes-or-no-p
1183 (if (string= (file-name-nondirectory filename)
1184 (buffer-name buf))
1185 (format
1186 (if (buffer-modified-p buf)
1187 "File %s changed on disk. Discard your edits? "
1188 "File %s changed on disk. Reread from disk? ")
1189 (file-name-nondirectory filename))
1190 (format
1191 (if (buffer-modified-p buf)
1192 "File %s changed on disk. Discard your edits in %s? "
1193 "File %s changed on disk. Reread from disk into %s? ")
1194 (file-name-nondirectory filename)
1195 (buffer-name buf))))
1196 (with-current-buffer buf
1197 (revert-buffer t t)))))
1198 (with-current-buffer buf
1199
1200 ;; Check if a formerly read-only file has become
1201 ;; writable and vice versa, but if the buffer agrees
1202 ;; with the new state of the file, that is ok too.
1203 (let ((read-only (not (file-writable-p buffer-file-name))))
1204 (unless (or (eq read-only buffer-file-read-only)
1205 (eq read-only buffer-read-only))
1206 (when (or nowarn
1207 (let ((question
1208 (format "File %s is %s on disk. Change buffer mode? "
1209 buffer-file-name
1210 (if read-only "read-only" "writable"))))
1211 (y-or-n-p question)))
1212 (setq buffer-read-only read-only)))
1213 (setq buffer-file-read-only read-only))
1214
1215 (when (and (not (eq (not (null rawfile))
1216 (not (null find-file-literally))))
1217 ;; It is confusing to ask whether to visit
1218 ;; non-literally if they have the file in
1219 ;; hexl-mode.
1220 (not (eq major-mode 'hexl-mode)))
1221 (if (buffer-modified-p)
1222 (if (y-or-n-p (if rawfile
1223 "Save file and revisit literally? "
1224 "Save file and revisit non-literally? "))
1225 (progn
1226 (save-buffer)
1227 (find-file-noselect-1 buf filename nowarn
1228 rawfile truename number))
1229 (if (y-or-n-p (if rawfile
1230 "Discard your edits and revisit file literally? "
1231 "Discard your edits and revisit file non-literally? "))
1232 (find-file-noselect-1 buf filename nowarn
1233 rawfile truename number)
1234 (error (if rawfile "File already visited non-literally"
1235 "File already visited literally"))))
1236 (if (y-or-n-p (if rawfile
1237 "Revisit file literally? "
1238 "Revisit file non-literally? "))
1239 (find-file-noselect-1 buf filename nowarn
1240 rawfile truename number)
1241 (error (if rawfile "File already visited non-literally"
1242 "File already visited literally"))))))
1243 ;; Return the buffer we are using.
1244 buf)
1245 ;; Create a new buffer.
1246 (setq buf (create-file-buffer filename))
1247 (set-buffer-major-mode buf)
1248 ;; find-file-noselect-1 may use a different buffer.
1249 (find-file-noselect-1 buf filename nowarn
1250 rawfile truename number))))))
1251
1252 (defun find-file-noselect-1 (buf filename nowarn rawfile truename number)
1253 (let ((inhibit-read-only t)
1254 error)
1255 (with-current-buffer buf
1256 (kill-local-variable 'find-file-literally)
1257 ;; Needed in case we are re-visiting the file with a different
1258 ;; text representation.
1259 (kill-local-variable 'buffer-file-coding-system)
1260 (kill-local-variable 'cursor-type)
1261 (erase-buffer)
1262 (and (default-value 'enable-multibyte-characters)
1263 (not rawfile)
1264 (set-buffer-multibyte t))
1265 (if rawfile
1266 (condition-case ()
1267 (insert-file-contents-literally filename t)
1268 (file-error
1269 (when (and (file-exists-p filename)
1270 (not (file-readable-p filename)))
1271 (kill-buffer buf)
1272 (signal 'file-error (list "File is not readable"
1273 filename)))
1274 ;; Unconditionally set error
1275 (setq error t)))
1276 (condition-case ()
1277 (insert-file-contents filename t)
1278 (file-error
1279 (when (and (file-exists-p filename)
1280 (not (file-readable-p filename)))
1281 (kill-buffer buf)
1282 (signal 'file-error (list "File is not readable"
1283 filename)))
1284 ;; Run find-file-not-found-hooks until one returns non-nil.
1285 (or (run-hook-with-args-until-success 'find-file-not-found-functions)
1286 ;; If they fail too, set error.
1287 (setq error t)))))
1288 ;; Record the file's truename, and maybe use that as visited name.
1289 (if (equal filename buffer-file-name)
1290 (setq buffer-file-truename truename)
1291 (setq buffer-file-truename
1292 (abbreviate-file-name (file-truename buffer-file-name))))
1293 (setq buffer-file-number number)
1294 ;; On VMS, we may want to remember which directory in a search list
1295 ;; the file was found in.
1296 (and (eq system-type 'vax-vms)
1297 (let (logical)
1298 (if (string-match ":" (file-name-directory filename))
1299 (setq logical (substring (file-name-directory filename)
1300 0 (match-beginning 0))))
1301 (not (member logical find-file-not-true-dirname-list)))
1302 (setq buffer-file-name buffer-file-truename))
1303 (if find-file-visit-truename
1304 (setq buffer-file-name
1305 (setq filename
1306 (expand-file-name buffer-file-truename))))
1307 ;; Set buffer's default directory to that of the file.
1308 (setq default-directory (file-name-directory buffer-file-name))
1309 ;; Turn off backup files for certain file names. Since
1310 ;; this is a permanent local, the major mode won't eliminate it.
1311 (and (not (funcall backup-enable-predicate buffer-file-name))
1312 (progn
1313 (make-local-variable 'backup-inhibited)
1314 (setq backup-inhibited t)))
1315 (if rawfile
1316 (progn
1317 (set-buffer-multibyte nil)
1318 (setq buffer-file-coding-system 'no-conversion)
1319 (make-local-variable 'find-file-literally)
1320 (setq find-file-literally t))
1321 (after-find-file error (not nowarn)))
1322 (current-buffer))))
1323 \f
1324 (defun insert-file-contents-literally (filename &optional visit beg end replace)
1325 "Like `insert-file-contents', but only reads in the file literally.
1326 A buffer may be modified in several ways after reading into the buffer,
1327 to Emacs features such as format decoding, character code
1328 conversion, `find-file-hook', automatic uncompression, etc.
1329
1330 This function ensures that none of these modifications will take place."
1331 (let ((format-alist nil)
1332 (after-insert-file-functions nil)
1333 (coding-system-for-read 'no-conversion)
1334 (coding-system-for-write 'no-conversion)
1335 (find-buffer-file-type-function
1336 (if (fboundp 'find-buffer-file-type)
1337 (symbol-function 'find-buffer-file-type)
1338 nil))
1339 (inhibit-file-name-handlers '(jka-compr-handler image-file-handler))
1340 (inhibit-file-name-operation 'insert-file-contents))
1341 (unwind-protect
1342 (progn
1343 (fset 'find-buffer-file-type (lambda (filename) t))
1344 (insert-file-contents filename visit beg end replace))
1345 (if find-buffer-file-type-function
1346 (fset 'find-buffer-file-type find-buffer-file-type-function)
1347 (fmakunbound 'find-buffer-file-type)))))
1348
1349 (defun insert-file-1 (filename insert-func)
1350 (if (file-directory-p filename)
1351 (signal 'file-error (list "Opening input file" "file is a directory"
1352 filename)))
1353 (let* ((buffer (find-buffer-visiting (abbreviate-file-name (file-truename filename))
1354 #'buffer-modified-p))
1355 (tem (funcall insert-func filename)))
1356 (push-mark (+ (point) (car (cdr tem))))
1357 (when buffer
1358 (message "File %s already visited and modified in buffer %s"
1359 filename (buffer-name buffer)))))
1360
1361 (defun insert-file-literally (filename)
1362 "Insert contents of file FILENAME into buffer after point with no conversion.
1363
1364 This function is meant for the user to run interactively.
1365 Don't call it from programs! Use `insert-file-contents-literally' instead.
1366 \(Its calling sequence is different; see its documentation)."
1367 (interactive "*fInsert file literally: ")
1368 (insert-file-1 filename #'insert-file-contents-literally))
1369
1370 (defvar find-file-literally nil
1371 "Non-nil if this buffer was made by `find-file-literally' or equivalent.
1372 This is a permanent local.")
1373 (put 'find-file-literally 'permanent-local t)
1374
1375 (defun find-file-literally (filename)
1376 "Visit file FILENAME with no conversion of any kind.
1377 Format conversion and character code conversion are both disabled,
1378 and multibyte characters are disabled in the resulting buffer.
1379 The major mode used is Fundamental mode regardless of the file name,
1380 and local variable specifications in the file are ignored.
1381 Automatic uncompression and adding a newline at the end of the
1382 file due to `require-final-newline' is also disabled.
1383
1384 You cannot absolutely rely on this function to result in
1385 visiting the file literally. If Emacs already has a buffer
1386 which is visiting the file, you get the existing buffer,
1387 regardless of whether it was created literally or not.
1388
1389 In a Lisp program, if you want to be sure of accessing a file's
1390 contents literally, you should create a temporary buffer and then read
1391 the file contents into it using `insert-file-contents-literally'."
1392 (interactive "FFind file literally: ")
1393 (switch-to-buffer (find-file-noselect filename nil t)))
1394 \f
1395 (defvar after-find-file-from-revert-buffer nil)
1396
1397 (defun after-find-file (&optional error warn noauto
1398 after-find-file-from-revert-buffer
1399 nomodes)
1400 "Called after finding a file and by the default revert function.
1401 Sets buffer mode, parses local variables.
1402 Optional args ERROR, WARN, and NOAUTO: ERROR non-nil means there was an
1403 error in reading the file. WARN non-nil means warn if there
1404 exists an auto-save file more recent than the visited file.
1405 NOAUTO means don't mess with auto-save mode.
1406 Fourth arg AFTER-FIND-FILE-FROM-REVERT-BUFFER non-nil
1407 means this call was from `revert-buffer'.
1408 Fifth arg NOMODES non-nil means don't alter the file's modes.
1409 Finishes by calling the functions in `find-file-hook'
1410 unless NOMODES is non-nil."
1411 (setq buffer-read-only (not (file-writable-p buffer-file-name)))
1412 (if noninteractive
1413 nil
1414 (let* (not-serious
1415 (msg
1416 (cond
1417 ((not warn) nil)
1418 ((and error (file-attributes buffer-file-name))
1419 (setq buffer-read-only t)
1420 "File exists, but cannot be read")
1421 ((not buffer-read-only)
1422 (if (and warn
1423 ;; No need to warn if buffer is auto-saved
1424 ;; under the name of the visited file.
1425 (not (and buffer-file-name
1426 auto-save-visited-file-name))
1427 (file-newer-than-file-p (or buffer-auto-save-file-name
1428 (make-auto-save-file-name))
1429 buffer-file-name))
1430 (format "%s has auto save data; consider M-x recover-this-file"
1431 (file-name-nondirectory buffer-file-name))
1432 (setq not-serious t)
1433 (if error "(New file)" nil)))
1434 ((not error)
1435 (setq not-serious t)
1436 "Note: file is write protected")
1437 ((file-attributes (directory-file-name default-directory))
1438 "File not found and directory write-protected")
1439 ((file-exists-p (file-name-directory buffer-file-name))
1440 (setq buffer-read-only nil))
1441 (t
1442 (setq buffer-read-only nil)
1443 (if (file-exists-p (file-name-directory (directory-file-name (file-name-directory buffer-file-name))))
1444 "Use M-x make-directory RET RET to create the directory"
1445 "Use C-u M-x make-directory RET RET to create directory and its parents")))))
1446 (when msg
1447 (message "%s" msg)
1448 (or not-serious (sit-for 1 nil t))))
1449 (when (and auto-save-default (not noauto))
1450 (auto-save-mode t)))
1451 ;; Make people do a little extra work (C-x C-q)
1452 ;; before altering a backup file.
1453 (when (backup-file-name-p buffer-file-name)
1454 (setq buffer-read-only t))
1455 ;; When a file is marked read-only,
1456 ;; make the buffer read-only even if root is looking at it.
1457 (when (and (file-modes (buffer-file-name))
1458 (zerop (logand (file-modes (buffer-file-name)) #o222)))
1459 (setq buffer-read-only t))
1460 (unless nomodes
1461 (when (and view-read-only view-mode)
1462 (view-mode-disable))
1463 (normal-mode t)
1464 (when (and buffer-read-only
1465 view-read-only
1466 (not (eq (get major-mode 'mode-class) 'special)))
1467 (view-mode-enter))
1468 (run-hooks 'find-file-hook)))
1469
1470 (defun normal-mode (&optional find-file)
1471 "Choose the major mode for this buffer automatically.
1472 Also sets up any specified local variables of the file.
1473 Uses the visited file name, the -*- line, and the local variables spec.
1474
1475 This function is called automatically from `find-file'. In that case,
1476 we may set up the file-specified mode and local variables,
1477 depending on the value of `enable-local-variables': if it is t, we do;
1478 if it is nil, we don't; otherwise, we query.
1479 In addition, if `local-enable-local-variables' is nil, we do
1480 not set local variables (though we do notice a mode specified with -*-.)
1481
1482 `enable-local-variables' is ignored if you run `normal-mode' interactively,
1483 or from Lisp without specifying the optional argument FIND-FILE;
1484 in that case, this function acts as if `enable-local-variables' were t."
1485 (interactive)
1486 (or find-file (funcall (or default-major-mode 'fundamental-mode)))
1487 (condition-case err
1488 (set-auto-mode)
1489 (error (message "File mode specification error: %s"
1490 (prin1-to-string err))))
1491 (condition-case err
1492 (let ((enable-local-variables (or (not find-file)
1493 enable-local-variables)))
1494 (hack-local-variables))
1495 (error (message "File local-variables error: %s"
1496 (prin1-to-string err))))
1497 (if (fboundp 'ucs-set-table-for-input) ; don't lose when building
1498 (ucs-set-table-for-input)))
1499
1500 (defvar auto-mode-alist
1501 (mapc
1502 (lambda (elt)
1503 (cons (purecopy (car elt)) (cdr elt)))
1504 '(("\\.te?xt\\'" . text-mode)
1505 ("\\.c\\'" . c-mode)
1506 ("\\.h\\'" . c-mode)
1507 ("\\.tex\\'" . tex-mode)
1508 ("\\.ltx\\'" . latex-mode)
1509 ("\\.el\\'" . emacs-lisp-mode)
1510 ("\\.scm\\'" . scheme-mode)
1511 ("\\.l\\'" . lisp-mode)
1512 ("\\.lisp\\'" . lisp-mode)
1513 ("\\.f\\'" . fortran-mode)
1514 ("\\.F\\'" . fortran-mode)
1515 ("\\.for\\'" . fortran-mode)
1516 ("\\.p\\'" . pascal-mode)
1517 ("\\.pas\\'" . pascal-mode)
1518 ("\\.ad[abs]\\'" . ada-mode)
1519 ("\\.ad[bs].dg\\'" . ada-mode)
1520 ("\\.\\([pP]\\([Llm]\\|erl\\)\\|al\\)\\'" . perl-mode)
1521 ("\\.s?html?\\'" . html-mode)
1522 ("\\.cc\\'" . c++-mode)
1523 ("\\.hh\\'" . c++-mode)
1524 ("\\.hpp\\'" . c++-mode)
1525 ("\\.C\\'" . c++-mode)
1526 ("\\.H\\'" . c++-mode)
1527 ("\\.cpp\\'" . c++-mode)
1528 ("\\.cxx\\'" . c++-mode)
1529 ("\\.hxx\\'" . c++-mode)
1530 ("\\.c\\+\\+\\'" . c++-mode)
1531 ("\\.h\\+\\+\\'" . c++-mode)
1532 ("\\.m\\'" . objc-mode)
1533 ("\\.java\\'" . java-mode)
1534 ("\\.mk\\'" . makefile-mode)
1535 ("\\(M\\|m\\|GNUm\\)akefile\\'" . makefile-mode)
1536 ("\\.am\\'" . makefile-mode) ;For Automake.
1537 ;; Less common extensions come here
1538 ;; so more common ones above are found faster.
1539 ("\\.texinfo\\'" . texinfo-mode)
1540 ("\\.te?xi\\'" . texinfo-mode)
1541 ("\\.s\\'" . asm-mode)
1542 ("\\.S\\'" . asm-mode)
1543 ("\\.asm\\'" . asm-mode)
1544 ("ChangeLog\\'" . change-log-mode)
1545 ("change\\.log\\'" . change-log-mode)
1546 ("changelo\\'" . change-log-mode)
1547 ("ChangeLog\\.[0-9]+\\'" . change-log-mode)
1548 ;; for MSDOS and MS-Windows (which are case-insensitive)
1549 ("changelog\\'" . change-log-mode)
1550 ("changelog\\.[0-9]+\\'" . change-log-mode)
1551 ("\\$CHANGE_LOG\\$\\.TXT" . change-log-mode)
1552 ("\\.scm\\.[0-9]*\\'" . scheme-mode)
1553 ("\\.[ck]?sh\\'\\|\\.shar\\'\\|/\\.z?profile\\'" . sh-mode)
1554 ("\\.bash\\'" . sh-mode)
1555 ("\\(/\\|\\`\\)\\.\\(bash_profile\\|z?login\\|bash_login\\|z?logout\\)\\'" . sh-mode)
1556 ("\\(/\\|\\`\\)\\.\\(bash_logout\\|shrc\\|[kz]shrc\\|bashrc\\|t?cshrc\\|esrc\\)\\'" . sh-mode)
1557 ("\\(/\\|\\`\\)\\.\\([kz]shenv\\|xinitrc\\|startxrc\\|xsession\\)\\'" . sh-mode)
1558 ("\\.m?spec\\'" . sh-mode)
1559 ("\\.mm\\'" . nroff-mode)
1560 ("\\.me\\'" . nroff-mode)
1561 ("\\.ms\\'" . nroff-mode)
1562 ("\\.man\\'" . nroff-mode)
1563 ("\\.\\(u?lpc\\|pike\\|pmod\\)\\'" . pike-mode)
1564 ("\\.TeX\\'" . tex-mode)
1565 ("\\.sty\\'" . latex-mode)
1566 ("\\.cls\\'" . latex-mode) ;LaTeX 2e class
1567 ("\\.clo\\'" . latex-mode) ;LaTeX 2e class option
1568 ("\\.bbl\\'" . latex-mode)
1569 ("\\.bib\\'" . bibtex-mode)
1570 ("\\.sql\\'" . sql-mode)
1571 ("\\.m4\\'" . m4-mode)
1572 ("\\.mc\\'" . m4-mode)
1573 ("\\.mf\\'" . metafont-mode)
1574 ("\\.mp\\'" . metapost-mode)
1575 ("\\.vhdl?\\'" . vhdl-mode)
1576 ("\\.article\\'" . text-mode)
1577 ("\\.letter\\'" . text-mode)
1578 ("\\.tcl\\'" . tcl-mode)
1579 ("\\.exp\\'" . tcl-mode)
1580 ("\\.itcl\\'" . tcl-mode)
1581 ("\\.itk\\'" . tcl-mode)
1582 ("\\.icn\\'" . icon-mode)
1583 ("\\.sim\\'" . simula-mode)
1584 ("\\.mss\\'" . scribe-mode)
1585 ("\\.f90\\'" . f90-mode)
1586 ("\\.f95\\'" . f90-mode)
1587 ("\\.indent\\.pro\\'" . fundamental-mode) ; to avoid idlwave-mode
1588 ("\\.pro\\'" . idlwave-mode)
1589 ("\\.lsp\\'" . lisp-mode)
1590 ("\\.awk\\'" . awk-mode)
1591 ("\\.prolog\\'" . prolog-mode)
1592 ("\\.tar\\'" . tar-mode)
1593 ("\\.\\(arc\\|zip\\|lzh\\|zoo\\|ear\\|jar\\|war\\)\\'" . archive-mode)
1594 ("\\.\\(ARC\\|ZIP\\|LZH\\|ZOO\\|EAR\\|JAR\\|WAR\\)\\'" . archive-mode)
1595 ("\\.sx[dmicw]\\'" . archive-mode) ; OpenOffice.org
1596 ;; Mailer puts message to be edited in
1597 ;; /tmp/Re.... or Message
1598 ("\\`/tmp/Re" . text-mode)
1599 ("/Message[0-9]*\\'" . text-mode)
1600 ("/drafts/[0-9]+\\'" . mh-letter-mode)
1601 ("\\.zone\\'" . zone-mode)
1602 ;; some news reader is reported to use this
1603 ("\\`/tmp/fol/" . text-mode)
1604 ("\\.y\\'" . c-mode)
1605 ("\\.lex\\'" . c-mode)
1606 ("\\.oak\\'" . scheme-mode)
1607 ("\\.sgml?\\'" . sgml-mode)
1608 ("\\.xml\\'" . sgml-mode)
1609 ("\\.dtd\\'" . sgml-mode)
1610 ("\\.ds\\(ss\\)?l\\'" . dsssl-mode)
1611 ("\\.idl\\'" . idl-mode)
1612 ;; .emacs or .gnus or .viper following a directory delimiter in
1613 ;; Unix, MSDOG or VMS syntax.
1614 ("[]>:/\\]\\..*\\(emacs\\|gnus\\|viper\\)\\'" . emacs-lisp-mode)
1615 ("\\`\\..*emacs\\'" . emacs-lisp-mode)
1616 ;; _emacs following a directory delimiter
1617 ;; in MsDos syntax
1618 ("[:/]_emacs\\'" . emacs-lisp-mode)
1619 ("/crontab\\.X*[0-9]+\\'" . shell-script-mode)
1620 ("\\.ml\\'" . lisp-mode)
1621 ("\\.\\(asn\\|mib\\|smi\\)\\'" . snmp-mode)
1622 ("\\.\\(as\\|mi\\|sm\\)2\\'" . snmpv2-mode)
1623 ("\\.\\(diffs?\\|patch\\|rej\\)\\'" . diff-mode)
1624 ("\\.\\(dif\\|pat\\)\\'" . diff-mode) ; for MSDOG
1625 ("\\.[eE]?[pP][sS]\\'" . ps-mode)
1626 ("configure\\.\\(ac\\|in\\)\\'" . autoconf-mode)
1627 ("BROWSE\\'" . ebrowse-tree-mode)
1628 ("\\.ebrowse\\'" . ebrowse-tree-mode)
1629 ("#\\*mail\\*" . mail-mode)
1630 ;; Get rid of any trailing .n.m and try again.
1631 ;; This is for files saved by cvs-merge that look like .#<file>.<rev>
1632 ;; or .#<file>.<rev>-<rev> or VC's <file>.~<rev>~.
1633 ;; Using mode nil rather than `ignore' would let the search continue
1634 ;; through this list (with the shortened name) rather than start over.
1635 ("\\.~?[0-9]+\\.[0-9][-.0-9]*~?\\'" ignore t)
1636 ;; The following should come after the ChangeLog pattern
1637 ;; for the sake of ChangeLog.1, etc.
1638 ;; and after the .scm.[0-9] and CVS' <file>.<rev> patterns too.
1639 ("\\.[1-9]\\'" . nroff-mode)
1640 ("\\.g\\'" . antlr-mode)
1641 ("\\.ses\\'" . ses-mode)
1642 ("\\.in\\'" nil t)))
1643 "Alist of filename patterns vs corresponding major mode functions.
1644 Each element looks like (REGEXP . FUNCTION) or (REGEXP FUNCTION NON-NIL).
1645 \(NON-NIL stands for anything that is not nil; the value does not matter.)
1646 Visiting a file whose name matches REGEXP specifies FUNCTION as the
1647 mode function to use. FUNCTION will be called, unless it is nil.
1648
1649 If the element has the form (REGEXP FUNCTION NON-NIL), then after
1650 calling FUNCTION (if it's not nil), we delete the suffix that matched
1651 REGEXP and search the list again for another match.")
1652
1653
1654 (defvar interpreter-mode-alist
1655 (mapc
1656 (lambda (l)
1657 (cons (purecopy (car l)) (cdr l)))
1658 '(("perl" . perl-mode)
1659 ("perl5" . perl-mode)
1660 ("miniperl" . perl-mode)
1661 ("wish" . tcl-mode)
1662 ("wishx" . tcl-mode)
1663 ("tcl" . tcl-mode)
1664 ("tclsh" . tcl-mode)
1665 ("awk" . awk-mode)
1666 ("mawk" . awk-mode)
1667 ("nawk" . awk-mode)
1668 ("gawk" . awk-mode)
1669 ("scm" . scheme-mode)
1670 ("ash" . sh-mode)
1671 ("bash" . sh-mode)
1672 ("bash2" . sh-mode)
1673 ("csh" . sh-mode)
1674 ("dtksh" . sh-mode)
1675 ("es" . sh-mode)
1676 ("itcsh" . sh-mode)
1677 ("jsh" . sh-mode)
1678 ("ksh" . sh-mode)
1679 ("oash" . sh-mode)
1680 ("pdksh" . sh-mode)
1681 ("rc" . sh-mode)
1682 ("rpm" . sh-mode)
1683 ("sh" . sh-mode)
1684 ("sh5" . sh-mode)
1685 ("tcsh" . sh-mode)
1686 ("wksh" . sh-mode)
1687 ("wsh" . sh-mode)
1688 ("zsh" . sh-mode)
1689 ("tail" . text-mode)
1690 ("more" . text-mode)
1691 ("less" . text-mode)
1692 ("pg" . text-mode)
1693 ("make" . makefile-mode) ; Debian uses this
1694 ("guile" . scheme-mode)
1695 ("clisp" . lisp-mode)))
1696 "Alist mapping interpreter names to major modes.
1697 This alist applies to files whose first line starts with `#!'.
1698 Each element looks like (INTERPRETER . MODE).
1699 The car of each element is compared with
1700 the name of the interpreter specified in the first line.
1701 If it matches, mode MODE is selected.")
1702
1703 (defvar inhibit-first-line-modes-regexps '("\\.tar\\'" "\\.tgz\\'")
1704 "List of regexps; if one matches a file name, don't look for `-*-'.")
1705
1706 (defvar inhibit-first-line-modes-suffixes nil
1707 "List of regexps for what to ignore, for `inhibit-first-line-modes-regexps'.
1708 When checking `inhibit-first-line-modes-regexps', we first discard
1709 from the end of the file name anything that matches one of these regexps.")
1710
1711 (defvar auto-mode-interpreter-regexp
1712 "#![ \t]?\\([^ \t\n]*\
1713 /bin/env[ \t]\\)?\\([^ \t\n]+\\)"
1714 "Regular expression matching interpreters, for file mode determination.
1715 This regular expression is matched against the first line of a file
1716 to determine the file's mode in `set-auto-mode' when Emacs can't deduce
1717 a mode from the file's name. If it matches, the file is assumed to
1718 be interpreted by the interpreter matched by the second group of the
1719 regular expression. The mode is then determined as the mode associated
1720 with that interpreter in `interpreter-mode-alist'.")
1721
1722 (defun set-auto-mode (&optional just-from-file-name)
1723 "Select major mode appropriate for current buffer.
1724 This checks for a -*- mode tag in the buffer's text,
1725 compares the filename against the entries in `auto-mode-alist',
1726 or checks the interpreter that runs this file against
1727 `interpreter-mode-alist'.
1728
1729 It does not check for the `mode:' local variable in the
1730 Local Variables section of the file; for that, use `hack-local-variables'.
1731
1732 If `enable-local-variables' is nil, this function does not check for a
1733 -*- mode tag.
1734
1735 If the optional argument JUST-FROM-FILE-NAME is non-nil,
1736 then we do not set anything but the major mode,
1737 and we don't even do that unless it would come from the file name."
1738 ;; Look for -*-MODENAME-*- or -*- ... mode: MODENAME; ... -*-
1739 (let (end done modes)
1740 (save-excursion
1741 (goto-char (point-min))
1742 (skip-chars-forward " \t\n")
1743 (and enable-local-variables
1744 (setq end (set-auto-mode-1))
1745 (if (save-excursion (search-forward ":" end t))
1746 ;; Find all specifications for the `mode:' variable
1747 ;; and execute them left to right.
1748 (while (let ((case-fold-search t))
1749 (or (and (looking-at "mode:")
1750 (goto-char (match-end 0)))
1751 (re-search-forward "[ \t;]mode:" end t)))
1752 (skip-chars-forward " \t")
1753 (let ((beg (point)))
1754 (if (search-forward ";" end t)
1755 (forward-char -1)
1756 (goto-char end))
1757 (skip-chars-backward " \t")
1758 (push (intern (concat (downcase (buffer-substring beg (point))) "-mode"))
1759 modes)))
1760 ;; Simple -*-MODE-*- case.
1761 (push (intern (concat (downcase (buffer-substring (point) end))
1762 "-mode"))
1763 modes))))
1764 ;; If we found modes to use, invoke them now,
1765 ;; outside the save-excursion.
1766 (unless just-from-file-name
1767 (dolist (mode (nreverse modes))
1768 (if (not (functionp mode))
1769 (message "Ignoring unknown mode `%s'" mode)
1770 (setq done t)
1771 (funcall mode))))
1772 ;; If we didn't find a mode from a -*- line, try using the file name.
1773 (if (and (not done) buffer-file-name)
1774 (let ((name buffer-file-name)
1775 (keep-going t))
1776 ;; Remove backup-suffixes from file name.
1777 (setq name (file-name-sans-versions name))
1778 (while keep-going
1779 (setq keep-going nil)
1780 (let ((alist auto-mode-alist)
1781 (mode nil))
1782 ;; Find first matching alist entry.
1783 (let ((case-fold-search
1784 (memq system-type '(vax-vms windows-nt cygwin))))
1785 (while (and (not mode) alist)
1786 (if (string-match (car (car alist)) name)
1787 (if (and (consp (cdr (car alist)))
1788 (nth 2 (car alist)))
1789 (setq mode (car (cdr (car alist)))
1790 name (substring name 0 (match-beginning 0))
1791 keep-going t)
1792 (setq mode (cdr (car alist))
1793 keep-going nil)))
1794 (setq alist (cdr alist))))
1795 (if mode
1796 ;; When JUST-FROM-FILE-NAME is set,
1797 ;; we are working on behalf of set-visited-file-name.
1798 ;; In that case, if the major mode specified is the
1799 ;; same one we already have, don't actually reset it.
1800 ;; We don't want to lose minor modes such as Font Lock.
1801 (unless (and just-from-file-name (eq mode major-mode))
1802 (funcall mode))
1803 ;; If we can't deduce a mode from the file name,
1804 ;; look for an interpreter specified in the first line.
1805 ;; As a special case, allow for things like "#!/bin/env perl",
1806 ;; which finds the interpreter anywhere in $PATH.
1807 (let ((interpreter
1808 (save-excursion
1809 (goto-char (point-min))
1810 (if (looking-at auto-mode-interpreter-regexp)
1811 (match-string 2)
1812 "")))
1813 elt)
1814 ;; Map interpreter name to a mode.
1815 (setq elt (assoc (file-name-nondirectory interpreter)
1816 interpreter-mode-alist))
1817 (unless just-from-file-name
1818 (if elt
1819 (funcall (cdr elt))))))))))))
1820
1821
1822 (defun set-auto-mode-1 ()
1823 "Find the -*- spec in the buffer.
1824 Call with point at the place to start searching from.
1825 If one is found, set point to the beginning
1826 and return the position of the end.
1827 Otherwise, return nil; point may be changed."
1828 (let (beg end)
1829 (and
1830 ;; Don't look for -*- if this file name matches any
1831 ;; of the regexps in inhibit-first-line-modes-regexps.
1832 (let ((temp inhibit-first-line-modes-regexps)
1833 (name (if buffer-file-name
1834 (file-name-sans-versions buffer-file-name)
1835 (buffer-name))))
1836 (while (let ((sufs inhibit-first-line-modes-suffixes))
1837 (while (and sufs (not (string-match (car sufs) name)))
1838 (setq sufs (cdr sufs)))
1839 sufs)
1840 (setq name (substring name 0 (match-beginning 0))))
1841 (while (and temp
1842 (not (string-match (car temp) name)))
1843 (setq temp (cdr temp)))
1844 (not temp))
1845
1846 (search-forward "-*-" (save-excursion
1847 ;; If the file begins with "#!"
1848 ;; (exec interpreter magic), look
1849 ;; for mode frobs in the first two
1850 ;; lines. You cannot necessarily
1851 ;; put them in the first line of
1852 ;; such a file without screwing up
1853 ;; the interpreter invocation.
1854 (end-of-line (and (looking-at "^#!") 2))
1855 (point)) t)
1856 (progn
1857 (skip-chars-forward " \t")
1858 (setq beg (point))
1859 (search-forward "-*-"
1860 (save-excursion (end-of-line) (point))
1861 t))
1862 (progn
1863 (forward-char -3)
1864 (skip-chars-backward " \t")
1865 (setq end (point))
1866 (goto-char beg)
1867 end))))
1868
1869 (defun hack-local-variables-prop-line ()
1870 "Set local variables specified in the -*- line.
1871 Ignore any specification for `mode:' and `coding:';
1872 `set-auto-mode' should already have handled `mode:',
1873 `set-auto-coding' should already have handled `coding:'."
1874 (save-excursion
1875 (goto-char (point-min))
1876 (let ((result nil)
1877 (end (set-auto-mode-1))
1878 (enable-local-variables
1879 (and local-enable-local-variables enable-local-variables)))
1880 ;; Parse the -*- line into the `result' alist.
1881 (cond ((not end)
1882 nil)
1883 ((looking-at "[ \t]*\\([^ \t\n\r:;]+\\)\\([ \t]*-\\*-\\)")
1884 ;; Simple form: "-*- MODENAME -*-". Already handled.
1885 nil)
1886 (t
1887 ;; Hairy form: '-*-' [ <variable> ':' <value> ';' ]* '-*-'
1888 ;; (last ";" is optional).
1889 (while (< (point) end)
1890 (or (looking-at "[ \t]*\\([^ \t\n:]+\\)[ \t]*:[ \t]*")
1891 (error "Malformed -*- line"))
1892 (goto-char (match-end 0))
1893 ;; There used to be a downcase here,
1894 ;; but the manual didn't say so,
1895 ;; and people want to set var names that aren't all lc.
1896 (let ((key (intern (buffer-substring
1897 (match-beginning 1)
1898 (match-end 1))))
1899 (val (save-restriction
1900 (narrow-to-region (point) end)
1901 (read (current-buffer)))))
1902 ;; It is traditional to ignore
1903 ;; case when checking for `mode' in set-auto-mode,
1904 ;; so we must do that here as well.
1905 ;; That is inconsistent, but we're stuck with it.
1906 ;; The same can be said for `coding' in set-auto-coding.
1907 (or (equal (downcase (symbol-name key)) "mode")
1908 (equal (downcase (symbol-name key)) "coding")
1909 (setq result (cons (cons key val) result)))
1910 (skip-chars-forward " \t;")))
1911 (setq result (nreverse result))))
1912
1913 (if (and result
1914 (or (eq enable-local-variables t)
1915 (and enable-local-variables
1916 (save-window-excursion
1917 (condition-case nil
1918 (switch-to-buffer (current-buffer))
1919 (error
1920 ;; If we fail to switch in the selected window,
1921 ;; it is probably a minibuffer.
1922 ;; So try another window.
1923 (condition-case nil
1924 (switch-to-buffer-other-window (current-buffer))
1925 (error
1926 (switch-to-buffer-other-frame (current-buffer))))))
1927 (y-or-n-p (format "Set local variables as specified in -*- line of %s? "
1928 (file-name-nondirectory buffer-file-name)))))))
1929 (let ((enable-local-eval enable-local-eval))
1930 (while result
1931 (hack-one-local-variable (car (car result)) (cdr (car result)))
1932 (setq result (cdr result))))))))
1933
1934 (defvar hack-local-variables-hook nil
1935 "Normal hook run after processing a file's local variables specs.
1936 Major modes can use this to examine user-specified local variables
1937 in order to initialize other data structure based on them.")
1938
1939 (defun hack-local-variables (&optional mode-only)
1940 "Parse and put into effect this buffer's local variables spec.
1941 If MODE-ONLY is non-nil, all we do is check whether the major mode
1942 is specified, returning t if it is specified."
1943 (unless mode-only
1944 (hack-local-variables-prop-line))
1945 ;; Look for "Local variables:" line in last page.
1946 (let (mode-specified
1947 (enable-local-variables
1948 (and local-enable-local-variables enable-local-variables)))
1949 (save-excursion
1950 (goto-char (point-max))
1951 (search-backward "\n\^L" (max (- (point-max) 3000) (point-min)) 'move)
1952 (if (let ((case-fold-search t))
1953 (and (search-forward "Local Variables:" nil t)
1954 (or (eq enable-local-variables t)
1955 mode-only
1956 (and enable-local-variables
1957 (save-window-excursion
1958 (switch-to-buffer (current-buffer))
1959 (save-excursion
1960 (beginning-of-line)
1961 (set-window-start (selected-window) (point)))
1962 (y-or-n-p (format "Set local variables as specified at end of %s? "
1963 (if buffer-file-name
1964 (file-name-nondirectory
1965 buffer-file-name)
1966 (concat "buffer "
1967 (buffer-name))))))))))
1968 (let ((continue t)
1969 prefix prefixlen suffix beg
1970 mode-specified
1971 (enable-local-eval enable-local-eval))
1972 ;; The prefix is what comes before "local variables:" in its line.
1973 ;; The suffix is what comes after "local variables:" in its line.
1974 (skip-chars-forward " \t")
1975 (or (eolp)
1976 (setq suffix (buffer-substring (point)
1977 (progn (end-of-line) (point)))))
1978 (goto-char (match-beginning 0))
1979 (or (bolp)
1980 (setq prefix
1981 (buffer-substring (point)
1982 (progn (beginning-of-line) (point)))))
1983
1984 (if prefix (setq prefixlen (length prefix)
1985 prefix (regexp-quote prefix)))
1986 (if suffix (setq suffix (concat (regexp-quote suffix) "$")))
1987 (while continue
1988 ;; Look at next local variable spec.
1989 (if selective-display (re-search-forward "[\n\C-m]")
1990 (forward-line 1))
1991 ;; Skip the prefix, if any.
1992 (if prefix
1993 (if (looking-at prefix)
1994 (forward-char prefixlen)
1995 (error "Local variables entry is missing the prefix")))
1996 ;; Find the variable name; strip whitespace.
1997 (skip-chars-forward " \t")
1998 (setq beg (point))
1999 (skip-chars-forward "^:\n")
2000 (if (eolp) (error "Missing colon in local variables entry"))
2001 (skip-chars-backward " \t")
2002 (let* ((str (buffer-substring beg (point)))
2003 (var (read str))
2004 val)
2005 ;; Setting variable named "end" means end of list.
2006 (if (string-equal (downcase str) "end")
2007 (setq continue nil)
2008 ;; Otherwise read the variable value.
2009 (skip-chars-forward "^:")
2010 (forward-char 1)
2011 (setq val (read (current-buffer)))
2012 (skip-chars-backward "\n")
2013 (skip-chars-forward " \t")
2014 (or (if suffix (looking-at suffix) (eolp))
2015 (error "Local variables entry is terminated incorrectly"))
2016 (if mode-only
2017 (if (eq var 'mode)
2018 (setq mode-specified t))
2019 ;; Set the variable. "Variables" mode and eval are funny.
2020 (hack-one-local-variable var val))))))))
2021 (unless mode-only
2022 (run-hooks 'hack-local-variables-hook))
2023 mode-specified))
2024
2025 (defvar ignored-local-variables
2026 '(enable-local-eval)
2027 "Variables to be ignored in a file's local variable spec.")
2028
2029 ;; Get confirmation before setting these variables as locals in a file.
2030 (put 'debugger 'risky-local-variable t)
2031 (put 'enable-local-eval 'risky-local-variable t)
2032 (put 'ignored-local-variables 'risky-local-variable t)
2033 (put 'eval 'risky-local-variable t)
2034 (put 'file-name-handler-alist 'risky-local-variable t)
2035 (put 'inhibit-quit 'risky-local-variable t)
2036 (put 'minor-mode-alist 'risky-local-variable t)
2037 (put 'minor-mode-map-alist 'risky-local-variable t)
2038 (put 'minor-mode-overriding-map-alist 'risky-local-variable t)
2039 (put 'overriding-local-map 'risky-local-variable t)
2040 (put 'overriding-terminal-local-map 'risky-local-variable t)
2041 (put 'auto-mode-alist 'risky-local-variable t)
2042 (put 'after-load-alist 'risky-local-variable t)
2043 (put 'buffer-file-name 'risky-local-variable t)
2044 (put 'buffer-undo-list 'risky-local-variable t)
2045 (put 'buffer-auto-save-file-name 'risky-local-variable t)
2046 (put 'buffer-file-truename 'risky-local-variable t)
2047 (put 'default-text-properties 'risky-local-variable t)
2048 (put 'exec-path 'risky-local-variable t)
2049 (put 'load-path 'risky-local-variable t)
2050 (put 'exec-directory 'risky-local-variable t)
2051 (put 'process-environment 'risky-local-variable t)
2052 (put 'dabbrev-case-fold-search 'risky-local-variable t)
2053 (put 'dabbrev-case-replace 'risky-local-variable t)
2054 ;; Don't wait for outline.el to be loaded, for the sake of outline-minor-mode.
2055 (put 'outline-level 'risky-local-variable t)
2056 (put 'rmail-output-file-alist 'risky-local-variable t)
2057 (put 'font-lock-defaults 'risky-local-variable t)
2058 (put 'special-display-buffer-names 'risky-local-variable t)
2059 (put 'frame-title-format 'risky-local-variable t)
2060 (put 'global-mode-string 'risky-local-variable t)
2061 (put 'header-line-format 'risky-local-variable t)
2062 (put 'icon-title-format 'risky-local-variable t)
2063 (put 'input-method-alist 'risky-local-variable t)
2064 (put 'format-alist 'risky-local-variable t)
2065 (put 'vc-mode 'risky-local-variable t)
2066 (put 'imenu-generic-expression 'risky-local-variable t)
2067 (put 'imenu-index-alist 'risky-local-variable t)
2068 (put 'standard-input 'risky-local-variable t)
2069 (put 'standard-output 'risky-local-variable t)
2070 (put 'unread-command-events 'risky-local-variable t)
2071 (put 'max-lisp-eval-depth 'risky-local-variable t)
2072 (put 'max-specpdl-size 'risky-local-variable t)
2073 (put 'mode-line-format 'risky-local-variable t)
2074 (put 'mode-line-modified 'risky-local-variable t)
2075 (put 'mode-line-mule-info 'risky-local-variable t)
2076 (put 'mode-line-buffer-identification 'risky-local-variable t)
2077 (put 'mode-line-modes 'risky-local-variable t)
2078 (put 'mode-line-position 'risky-local-variable t)
2079 (put 'mode-line-process 'risky-local-variable t)
2080 (put 'mode-name 'risky-local-variable t)
2081 (put 'display-time-string 'risky-local-variable t)
2082 (put 'parse-time-rules 'risky-local-variable t)
2083
2084 ;; This case is safe because the user gets to check it before it is used.
2085 (put 'compile-command 'safe-local-variable 'stringp)
2086
2087 (defun risky-local-variable-p (sym val)
2088 "Non-nil if SYM could be dangerous as a file-local variable with value VAL.
2089 If VAL is nil, the question is whether any value might be dangerous."
2090 (let ((safep (get sym 'safe-local-variable)))
2091 (or (memq sym ignored-local-variables)
2092 (get sym 'risky-local-variable)
2093 (and (string-match "-hooks?$\\|-functions?$\\|-forms?$\\|-program$\\|-command$\\|-predicate$\\|font-lock-keywords$\\|font-lock-keywords-[0-9]+$\\|font-lock-syntactic-keywords$\\|-frame-alist$\\|-mode-alist$\\|-map$\\|-map-alist$"
2094 (symbol-name sym))
2095 (not safep))
2096 ;; If the safe-local-variable property isn't t or nil,
2097 ;; then it must return non-nil on the proposed value to be safe.
2098 (and (not (memq safep '(t nil)))
2099 (or (null val)
2100 (not (funcall safep val)))))))
2101
2102 (defcustom safe-local-eval-forms nil
2103 "*Expressions that are considered \"safe\" in an `eval:' local variable.
2104 Add expressions to this list if you want Emacs to evaluate them, when
2105 they appear in an `eval' local variable specification, without first
2106 asking you for confirmation."
2107 :group 'find-file
2108 :version "21.4"
2109 :type '(repeat sexp))
2110
2111 (put 'c-set-style 'safe-local-eval-function t)
2112
2113 (defun hack-one-local-variable-quotep (exp)
2114 (and (consp exp) (eq (car exp) 'quote) (consp (cdr exp))))
2115
2116 (defun hack-one-local-variable-constantp (exp)
2117 (or (and (not (symbolp exp)) (not (consp exp)))
2118 (memq exp '(t nil))
2119 (keywordp exp)
2120 (hack-one-local-variable-quotep exp)))
2121
2122 (defun hack-one-local-variable-eval-safep (exp)
2123 "Return t if it is safe to eval EXP when it is found in a file."
2124 (or (not (consp exp))
2125 ;; Detect certain `put' expressions.
2126 (and (eq (car exp) 'put)
2127 (hack-one-local-variable-quotep (nth 1 exp))
2128 (hack-one-local-variable-quotep (nth 2 exp))
2129 (memq (nth 1 (nth 2 exp))
2130 '(lisp-indent-hook))
2131 ;; Only allow safe values of lisp-indent-hook;
2132 ;; not functions.
2133 (or (numberp (nth 3 exp))
2134 (equal (nth 3 exp) ''defun)))
2135 ;; Allow expressions that the user requested.
2136 (member exp safe-local-eval-forms)
2137 ;; Certain functions can be allowed with safe arguments
2138 ;; or can specify verification functions to try.
2139 (and (symbolp (car exp))
2140 (let ((prop (get (car exp) 'safe-local-eval-function)))
2141 (cond ((eq prop t)
2142 (let ((ok t))
2143 (dolist (arg (cdr exp))
2144 (unless (hack-one-local-variable-constantp arg)
2145 (setq ok nil)))
2146 ok))
2147 ((functionp prop)
2148 (funcall prop exp))
2149 ((listp prop)
2150 (let ((ok nil))
2151 (dolist (function prop)
2152 (if (funcall function exp)
2153 (setq ok t)))
2154 ok)))))))
2155
2156 (defun hack-one-local-variable (var val)
2157 "\"Set\" one variable in a local variables spec.
2158 A few patterns are specified so that any name which matches one
2159 is considered risky."
2160 (cond ((eq var 'mode)
2161 (funcall (intern (concat (downcase (symbol-name val))
2162 "-mode"))))
2163 ((eq var 'coding)
2164 ;; We have already handled coding: tag in set-auto-coding.
2165 nil)
2166 ;; "Setting" eval means either eval it or do nothing.
2167 ;; Likewise for setting hook variables.
2168 ((risky-local-variable-p var val)
2169 ;; Permit evalling a put of a harmless property.
2170 ;; if the args do nothing tricky.
2171 (if (or (and (eq var 'eval)
2172 (hack-one-local-variable-eval-safep val))
2173 ;; Permit eval if not root and user says ok.
2174 (and (not (zerop (user-uid)))
2175 (or (eq enable-local-eval t)
2176 (and enable-local-eval
2177 (save-window-excursion
2178 (switch-to-buffer (current-buffer))
2179 (save-excursion
2180 (beginning-of-line)
2181 (set-window-start (selected-window) (point)))
2182 (setq enable-local-eval
2183 (y-or-n-p (format "Process `eval' or hook local variables in %s? "
2184 (if buffer-file-name
2185 (concat "file " (file-name-nondirectory buffer-file-name))
2186 (concat "buffer " (buffer-name)))))))))))
2187 (if (eq var 'eval)
2188 (save-excursion (eval val))
2189 (make-local-variable var)
2190 (set var val))
2191 (message "Ignoring risky spec in the local variables list")))
2192 ;; Ordinary variable, really set it.
2193 (t (make-local-variable var)
2194 ;; Make sure the string has no text properties.
2195 ;; Some text properties can get evaluated in various ways,
2196 ;; so it is risky to put them on with a local variable list.
2197 (if (stringp val)
2198 (set-text-properties 0 (length val) nil val))
2199 (set var val))))
2200
2201 \f
2202 (defcustom change-major-mode-with-file-name t
2203 "*Non-nil means \\[write-file] should set the major mode from the file name.
2204 However, the mode will not be changed if
2205 \(1) a local variables list or the `-*-' line specifies a major mode, or
2206 \(2) the current major mode is a \"special\" mode,
2207 \ not suitable for ordinary files, or
2208 \(3) the new file name does not particularly specify any mode."
2209 :type 'boolean
2210 :group 'editing-basics)
2211
2212 (defun set-visited-file-name (filename &optional no-query along-with-file)
2213 "Change name of file visited in current buffer to FILENAME.
2214 The next time the buffer is saved it will go in the newly specified file.
2215 nil or empty string as argument means make buffer not be visiting any file.
2216 Remember to delete the initial contents of the minibuffer
2217 if you wish to pass an empty string as the argument.
2218
2219 The optional second argument NO-QUERY, if non-nil, inhibits asking for
2220 confirmation in the case where another buffer is already visiting FILENAME.
2221
2222 The optional third argument ALONG-WITH-FILE, if non-nil, means that
2223 the old visited file has been renamed to the new name FILENAME."
2224 (interactive "FSet visited file name: ")
2225 (if (buffer-base-buffer)
2226 (error "An indirect buffer cannot visit a file"))
2227 (let (truename)
2228 (if filename
2229 (setq filename
2230 (if (string-equal filename "")
2231 nil
2232 (expand-file-name filename))))
2233 (if filename
2234 (progn
2235 (setq truename (file-truename filename))
2236 (if find-file-visit-truename
2237 (setq filename truename))))
2238 (let ((buffer (and filename (find-buffer-visiting filename))))
2239 (and buffer (not (eq buffer (current-buffer)))
2240 (not no-query)
2241 (not (y-or-n-p (message "A buffer is visiting %s; proceed? "
2242 filename)))
2243 (error "Aborted")))
2244 (or (equal filename buffer-file-name)
2245 (progn
2246 (and filename (lock-buffer filename))
2247 (unlock-buffer)))
2248 (setq buffer-file-name filename)
2249 (if filename ; make buffer name reflect filename.
2250 (let ((new-name (file-name-nondirectory buffer-file-name)))
2251 (if (string= new-name "")
2252 (error "Empty file name"))
2253 (if (eq system-type 'vax-vms)
2254 (setq new-name (downcase new-name)))
2255 (setq default-directory (file-name-directory buffer-file-name))
2256 (or (string= new-name (buffer-name))
2257 (rename-buffer new-name t))))
2258 (setq buffer-backed-up nil)
2259 (or along-with-file
2260 (clear-visited-file-modtime))
2261 ;; Abbreviate the file names of the buffer.
2262 (if truename
2263 (progn
2264 (setq buffer-file-truename (abbreviate-file-name truename))
2265 (if find-file-visit-truename
2266 (setq buffer-file-name buffer-file-truename))))
2267 (setq buffer-file-number
2268 (if filename
2269 (nthcdr 10 (file-attributes buffer-file-name))
2270 nil)))
2271 ;; write-file-functions is normally used for things like ftp-find-file
2272 ;; that visit things that are not local files as if they were files.
2273 ;; Changing to visit an ordinary local file instead should flush the hook.
2274 (kill-local-variable 'write-file-functions)
2275 (kill-local-variable 'local-write-file-hooks)
2276 (kill-local-variable 'revert-buffer-function)
2277 (kill-local-variable 'backup-inhibited)
2278 ;; If buffer was read-only because of version control,
2279 ;; that reason is gone now, so make it writable.
2280 (if vc-mode
2281 (setq buffer-read-only nil))
2282 (kill-local-variable 'vc-mode)
2283 ;; Turn off backup files for certain file names.
2284 ;; Since this is a permanent local, the major mode won't eliminate it.
2285 (and buffer-file-name
2286 (not (funcall backup-enable-predicate buffer-file-name))
2287 (progn
2288 (make-local-variable 'backup-inhibited)
2289 (setq backup-inhibited t)))
2290 (let ((oauto buffer-auto-save-file-name))
2291 ;; If auto-save was not already on, turn it on if appropriate.
2292 (if (not buffer-auto-save-file-name)
2293 (and buffer-file-name auto-save-default
2294 (auto-save-mode t))
2295 ;; If auto save is on, start using a new name.
2296 ;; We deliberately don't rename or delete the old auto save
2297 ;; for the old visited file name. This is because perhaps
2298 ;; the user wants to save the new state and then compare with the
2299 ;; previous state from the auto save file.
2300 (setq buffer-auto-save-file-name
2301 (make-auto-save-file-name)))
2302 ;; Rename the old auto save file if any.
2303 (and oauto buffer-auto-save-file-name
2304 (file-exists-p oauto)
2305 (rename-file oauto buffer-auto-save-file-name t)))
2306 (and buffer-file-name
2307 (not along-with-file)
2308 (set-buffer-modified-p t))
2309 ;; Update the major mode, if the file name determines it.
2310 (condition-case nil
2311 ;; Don't change the mode if it is special.
2312 (or (not change-major-mode-with-file-name)
2313 (get major-mode 'mode-class)
2314 ;; Don't change the mode if the local variable list specifies it.
2315 (hack-local-variables t)
2316 (set-auto-mode t))
2317 (error nil)))
2318
2319 (defun write-file (filename &optional confirm)
2320 "Write current buffer into file FILENAME.
2321 This makes the buffer visit that file, and marks it as not modified.
2322
2323 If you specify just a directory name as FILENAME, that means to use
2324 the default file name but in that directory. You can also yank
2325 the default file name into the minibuffer to edit it, using M-n.
2326
2327 If the buffer is not already visiting a file, the default file name
2328 for the output file is the buffer name.
2329
2330 If optional second arg CONFIRM is non-nil, this function
2331 asks for confirmation before overwriting an existing file.
2332 Interactively, confirmation is required unless you supply a prefix argument."
2333 ;; (interactive "FWrite file: ")
2334 (interactive
2335 (list (if buffer-file-name
2336 (read-file-name "Write file: "
2337 nil nil nil nil)
2338 (read-file-name "Write file: " default-directory
2339 (expand-file-name
2340 (file-name-nondirectory (buffer-name))
2341 default-directory)
2342 nil nil))
2343 (not current-prefix-arg)))
2344 (or (null filename) (string-equal filename "")
2345 (progn
2346 ;; If arg is just a directory,
2347 ;; use the default file name, but in that directory.
2348 (if (file-directory-p filename)
2349 (setq filename (concat (file-name-as-directory filename)
2350 (file-name-nondirectory
2351 (or buffer-file-name (buffer-name))))))
2352 (and confirm
2353 (file-exists-p filename)
2354 (or (y-or-n-p (format "File `%s' exists; overwrite? " filename))
2355 (error "Canceled")))
2356 (set-visited-file-name filename (not confirm))))
2357 (set-buffer-modified-p t)
2358 ;; Make buffer writable if file is writable.
2359 (and buffer-file-name
2360 (file-writable-p buffer-file-name)
2361 (setq buffer-read-only nil))
2362 (save-buffer))
2363 \f
2364 (defun backup-buffer ()
2365 "Make a backup of the disk file visited by the current buffer, if appropriate.
2366 This is normally done before saving the buffer the first time.
2367
2368 A backup may be done by renaming or by copying; see documentation of
2369 variable `make-backup-files'. If it's done by renaming, then the file is
2370 no longer accessible under its old name.
2371
2372 The value is non-nil after a backup was made by renaming.
2373 It has the form (MODES . BACKUPNAME).
2374 MODES is the result of `file-modes' on the original
2375 file; this means that the caller, after saving the buffer, should change
2376 the modes of the new file to agree with the old modes.
2377 BACKUPNAME is the backup file name, which is the old file renamed."
2378 (if (and make-backup-files (not backup-inhibited)
2379 (not buffer-backed-up)
2380 (file-exists-p buffer-file-name)
2381 (memq (aref (elt (file-attributes buffer-file-name) 8) 0)
2382 '(?- ?l)))
2383 (let ((real-file-name buffer-file-name)
2384 backup-info backupname targets setmodes)
2385 ;; If specified name is a symbolic link, chase it to the target.
2386 ;; Thus we make the backups in the directory where the real file is.
2387 (setq real-file-name (file-chase-links real-file-name))
2388 (setq backup-info (find-backup-file-name real-file-name)
2389 backupname (car backup-info)
2390 targets (cdr backup-info))
2391 ;; (if (file-directory-p buffer-file-name)
2392 ;; (error "Cannot save buffer in directory %s" buffer-file-name))
2393 (if backup-info
2394 (condition-case ()
2395 (let ((delete-old-versions
2396 ;; If have old versions to maybe delete,
2397 ;; ask the user to confirm now, before doing anything.
2398 ;; But don't actually delete til later.
2399 (and targets
2400 (or (eq delete-old-versions t) (eq delete-old-versions nil))
2401 (or delete-old-versions
2402 (y-or-n-p (format "Delete excess backup versions of %s? "
2403 real-file-name)))))
2404 (modes (file-modes buffer-file-name)))
2405 ;; Actually write the back up file.
2406 (condition-case ()
2407 (if (or file-precious-flag
2408 ; (file-symlink-p buffer-file-name)
2409 backup-by-copying
2410 ;; Don't rename a suid or sgid file.
2411 (and modes (< 0 (logand modes #o6000)))
2412 (and backup-by-copying-when-linked
2413 (> (file-nlinks real-file-name) 1))
2414 (and (or backup-by-copying-when-mismatch
2415 (integerp backup-by-copying-when-privileged-mismatch))
2416 (let ((attr (file-attributes real-file-name)))
2417 (and (or backup-by-copying-when-mismatch
2418 (and (integerp (nth 2 attr))
2419 (integerp backup-by-copying-when-privileged-mismatch)
2420 (<= (nth 2 attr) backup-by-copying-when-privileged-mismatch)))
2421 (or (nth 9 attr)
2422 (not (file-ownership-preserved-p real-file-name)))))))
2423 (backup-buffer-copy real-file-name backupname modes)
2424 ;; rename-file should delete old backup.
2425 (rename-file real-file-name backupname t)
2426 (setq setmodes (cons modes backupname)))
2427 (file-error
2428 ;; If trouble writing the backup, write it in ~.
2429 (setq backupname (expand-file-name
2430 (convert-standard-filename
2431 "~/%backup%~")))
2432 (message "Cannot write backup file; backing up in %s"
2433 (file-name-nondirectory backupname))
2434 (sleep-for 1)
2435 (backup-buffer-copy real-file-name backupname modes)))
2436 (setq buffer-backed-up t)
2437 ;; Now delete the old versions, if desired.
2438 (if delete-old-versions
2439 (while targets
2440 (condition-case ()
2441 (delete-file (car targets))
2442 (file-error nil))
2443 (setq targets (cdr targets))))
2444 setmodes)
2445 (file-error nil))))))
2446
2447 (defun backup-buffer-copy (from-name to-name modes)
2448 (condition-case ()
2449 (copy-file from-name to-name t t)
2450 (file-error
2451 ;; If copying fails because file TO-NAME
2452 ;; is not writable, delete that file and try again.
2453 (if (and (file-exists-p to-name)
2454 (not (file-writable-p to-name)))
2455 (delete-file to-name))
2456 (copy-file from-name to-name t t)))
2457 (set-file-modes to-name (logand modes #o1777)))
2458
2459 (defun file-name-sans-versions (name &optional keep-backup-version)
2460 "Return file NAME sans backup versions or strings.
2461 This is a separate procedure so your site-init or startup file can
2462 redefine it.
2463 If the optional argument KEEP-BACKUP-VERSION is non-nil,
2464 we do not remove backup version numbers, only true file version numbers."
2465 (let ((handler (find-file-name-handler name 'file-name-sans-versions)))
2466 (if handler
2467 (funcall handler 'file-name-sans-versions name keep-backup-version)
2468 (substring name 0
2469 (if (eq system-type 'vax-vms)
2470 ;; VMS version number is (a) semicolon, optional
2471 ;; sign, zero or more digits or (b) period, option
2472 ;; sign, zero or more digits, provided this is the
2473 ;; second period encountered outside of the
2474 ;; device/directory part of the file name.
2475 (or (string-match ";[-+]?[0-9]*\\'" name)
2476 (if (string-match "\\.[^]>:]*\\(\\.[-+]?[0-9]*\\)\\'"
2477 name)
2478 (match-beginning 1))
2479 (length name))
2480 (if keep-backup-version
2481 (length name)
2482 (or (string-match "\\.~[0-9.]+~\\'" name)
2483 (string-match "~\\'" name)
2484 (length name))))))))
2485
2486 (defun file-ownership-preserved-p (file)
2487 "Return t if deleting FILE and rewriting it would preserve the owner."
2488 (let ((handler (find-file-name-handler file 'file-ownership-preserved-p)))
2489 (if handler
2490 (funcall handler 'file-ownership-preserved-p file)
2491 (let ((attributes (file-attributes file)))
2492 ;; Return t if the file doesn't exist, since it's true that no
2493 ;; information would be lost by an (attempted) delete and create.
2494 (or (null attributes)
2495 (= (nth 2 attributes) (user-uid)))))))
2496
2497 (defun file-name-sans-extension (filename)
2498 "Return FILENAME sans final \"extension\".
2499 The extension, in a file name, is the part that follows the last `.',
2500 except that a leading `.', if any, doesn't count."
2501 (save-match-data
2502 (let ((file (file-name-sans-versions (file-name-nondirectory filename)))
2503 directory)
2504 (if (and (string-match "\\.[^.]*\\'" file)
2505 (not (eq 0 (match-beginning 0))))
2506 (if (setq directory (file-name-directory filename))
2507 ;; Don't use expand-file-name here; if DIRECTORY is relative,
2508 ;; we don't want to expand it.
2509 (concat directory (substring file 0 (match-beginning 0)))
2510 (substring file 0 (match-beginning 0)))
2511 filename))))
2512
2513 (defun file-name-extension (filename &optional period)
2514 "Return FILENAME's final \"extension\".
2515 The extension, in a file name, is the part that follows the last `.',
2516 except that a leading `.', if any, doesn't count.
2517 Return nil for extensionless file names such as `foo'.
2518 Return the empty string for file names such as `foo.'.
2519
2520 If PERIOD is non-nil, then the returned value includes the period
2521 that delimits the extension, and if FILENAME has no extension,
2522 the value is \"\"."
2523 (save-match-data
2524 (let ((file (file-name-sans-versions (file-name-nondirectory filename))))
2525 (if (and (string-match "\\.[^.]*\\'" file)
2526 (not (eq 0 (match-beginning 0))))
2527 (substring file (+ (match-beginning 0) (if period 0 1)))
2528 (if period
2529 "")))))
2530
2531 (defcustom make-backup-file-name-function nil
2532 "A function to use instead of the default `make-backup-file-name'.
2533 A value of nil gives the default `make-backup-file-name' behaviour.
2534
2535 This could be buffer-local to do something special for specific
2536 files. If you define it, you may need to change `backup-file-name-p'
2537 and `file-name-sans-versions' too.
2538
2539 See also `backup-directory-alist'."
2540 :group 'backup
2541 :type '(choice (const :tag "Default" nil)
2542 (function :tag "Your function")))
2543
2544 (defcustom backup-directory-alist nil
2545 "Alist of filename patterns and backup directory names.
2546 Each element looks like (REGEXP . DIRECTORY). Backups of files with
2547 names matching REGEXP will be made in DIRECTORY. DIRECTORY may be
2548 relative or absolute. If it is absolute, so that all matching files
2549 are backed up into the same directory, the file names in this
2550 directory will be the full name of the file backed up with all
2551 directory separators changed to `!' to prevent clashes. This will not
2552 work correctly if your filesystem truncates the resulting name.
2553
2554 For the common case of all backups going into one directory, the alist
2555 should contain a single element pairing \".\" with the appropriate
2556 directory name.
2557
2558 If this variable is nil, or it fails to match a filename, the backup
2559 is made in the original file's directory.
2560
2561 On MS-DOS filesystems without long names this variable is always
2562 ignored."
2563 :group 'backup
2564 :type '(repeat (cons (regexp :tag "Regexp matching filename")
2565 (directory :tag "Backup directory name"))))
2566
2567 (defun normal-backup-enable-predicate (name)
2568 "Default `backup-enable-predicate' function.
2569 Checks for files in `temporary-file-directory' or
2570 `small-temporary-file-directory'."
2571 (not (or (let ((comp (compare-strings temporary-file-directory 0 nil
2572 name 0 nil)))
2573 ;; Directory is under temporary-file-directory.
2574 (and (not (eq comp t))
2575 (< comp (- (length temporary-file-directory)))))
2576 (if small-temporary-file-directory
2577 (let ((comp (compare-strings small-temporary-file-directory
2578 0 nil
2579 name 0 nil)))
2580 ;; Directory is under small-temporary-file-directory.
2581 (and (not (eq comp t))
2582 (< comp (- (length small-temporary-file-directory)))))))))
2583
2584 (defun make-backup-file-name (file)
2585 "Create the non-numeric backup file name for FILE.
2586 Normally this will just be the file's name with `~' appended.
2587 Customization hooks are provided as follows.
2588
2589 If the variable `make-backup-file-name-function' is non-nil, its value
2590 should be a function which will be called with FILE as its argument;
2591 the resulting name is used.
2592
2593 Otherwise a match for FILE is sought in `backup-directory-alist'; see
2594 the documentation of that variable. If the directory for the backup
2595 doesn't exist, it is created."
2596 (if make-backup-file-name-function
2597 (funcall make-backup-file-name-function file)
2598 (if (and (eq system-type 'ms-dos)
2599 (not (msdos-long-file-names)))
2600 (let ((fn (file-name-nondirectory file)))
2601 (concat (file-name-directory file)
2602 (or (and (string-match "\\`[^.]+\\'" fn)
2603 (concat (match-string 0 fn) ".~"))
2604 (and (string-match "\\`[^.]+\\.\\(..?\\)?" fn)
2605 (concat (match-string 0 fn) "~")))))
2606 (concat (make-backup-file-name-1 file) "~"))))
2607
2608 (defun make-backup-file-name-1 (file)
2609 "Subroutine of `make-backup-file-name' and `find-backup-file-name'."
2610 (let ((alist backup-directory-alist)
2611 elt backup-directory failed)
2612 (while alist
2613 (setq elt (pop alist))
2614 (if (string-match (car elt) file)
2615 (setq backup-directory (cdr elt)
2616 alist nil)))
2617 (if (and backup-directory (not (file-exists-p backup-directory)))
2618 (condition-case nil
2619 (make-directory backup-directory 'parents)
2620 (file-error (setq backup-directory nil))))
2621 (if (null backup-directory)
2622 file
2623 (if (file-name-absolute-p backup-directory)
2624 (progn
2625 (when (memq system-type '(windows-nt ms-dos cygwin))
2626 ;; Normalize DOSish file names: downcase the drive
2627 ;; letter, if any, and replace the leading "x:" with
2628 ;; "/drive_x".
2629 (or (file-name-absolute-p file)
2630 (setq file (expand-file-name file))) ; make defaults explicit
2631 ;; Replace any invalid file-name characters (for the
2632 ;; case of backing up remote files).
2633 (setq file (expand-file-name (convert-standard-filename file)))
2634 (if (eq (aref file 1) ?:)
2635 (setq file (concat "/"
2636 "drive_"
2637 (char-to-string (downcase (aref file 0)))
2638 (if (eq (aref file 2) ?/)
2639 ""
2640 "/")
2641 (substring file 2)))))
2642 ;; Make the name unique by substituting directory
2643 ;; separators. It may not really be worth bothering about
2644 ;; doubling `!'s in the original name...
2645 (expand-file-name
2646 (subst-char-in-string
2647 ?/ ?!
2648 (replace-regexp-in-string "!" "!!" file))
2649 backup-directory))
2650 (expand-file-name (file-name-nondirectory file)
2651 (file-name-as-directory
2652 (expand-file-name backup-directory
2653 (file-name-directory file))))))))
2654
2655 (defun backup-file-name-p (file)
2656 "Return non-nil if FILE is a backup file name (numeric or not).
2657 This is a separate function so you can redefine it for customization.
2658 You may need to redefine `file-name-sans-versions' as well."
2659 (string-match "~\\'" file))
2660
2661 (defvar backup-extract-version-start)
2662
2663 ;; This is used in various files.
2664 ;; The usage of backup-extract-version-start is not very clean,
2665 ;; but I can't see a good alternative, so as of now I am leaving it alone.
2666 (defun backup-extract-version (fn)
2667 "Given the name of a numeric backup file, FN, return the backup number.
2668 Uses the free variable `backup-extract-version-start', whose value should be
2669 the index in the name where the version number begins."
2670 (if (and (string-match "[0-9]+~$" fn backup-extract-version-start)
2671 (= (match-beginning 0) backup-extract-version-start))
2672 (string-to-int (substring fn backup-extract-version-start -1))
2673 0))
2674
2675 ;; I believe there is no need to alter this behavior for VMS;
2676 ;; since backup files are not made on VMS, it should not get called.
2677 (defun find-backup-file-name (fn)
2678 "Find a file name for a backup file FN, and suggestions for deletions.
2679 Value is a list whose car is the name for the backup file
2680 and whose cdr is a list of old versions to consider deleting now.
2681 If the value is nil, don't make a backup.
2682 Uses `backup-directory-alist' in the same way as does
2683 `make-backup-file-name'."
2684 (let ((handler (find-file-name-handler fn 'find-backup-file-name)))
2685 ;; Run a handler for this function so that ange-ftp can refuse to do it.
2686 (if handler
2687 (funcall handler 'find-backup-file-name fn)
2688 (if (or (eq version-control 'never)
2689 ;; We don't support numbered backups on plain MS-DOS
2690 ;; when long file names are unavailable.
2691 (and (eq system-type 'ms-dos)
2692 (not (msdos-long-file-names))))
2693 (list (make-backup-file-name fn))
2694 (let* ((basic-name (make-backup-file-name-1 fn))
2695 (base-versions (concat (file-name-nondirectory basic-name)
2696 ".~"))
2697 (backup-extract-version-start (length base-versions))
2698 (high-water-mark 0)
2699 (number-to-delete 0)
2700 possibilities deserve-versions-p versions)
2701 (condition-case ()
2702 (setq possibilities (file-name-all-completions
2703 base-versions
2704 (file-name-directory basic-name))
2705 versions (sort (mapcar #'backup-extract-version
2706 possibilities)
2707 #'<)
2708 high-water-mark (apply 'max 0 versions)
2709 deserve-versions-p (or version-control
2710 (> high-water-mark 0))
2711 number-to-delete (- (length versions)
2712 kept-old-versions
2713 kept-new-versions
2714 -1))
2715 (file-error (setq possibilities nil)))
2716 (if (not deserve-versions-p)
2717 (list (make-backup-file-name fn))
2718 (cons (format "%s.~%d~" basic-name (1+ high-water-mark))
2719 (if (and (> number-to-delete 0)
2720 ;; Delete nothing if there is overflow
2721 ;; in the number of versions to keep.
2722 (>= (+ kept-new-versions kept-old-versions -1) 0))
2723 (mapcar (lambda (n)
2724 (format "%s.~%d~" basic-name n))
2725 (let ((v (nthcdr kept-old-versions versions)))
2726 (rplacd (nthcdr (1- number-to-delete) v) ())
2727 v))))))))))
2728
2729 (defun file-nlinks (filename)
2730 "Return number of names file FILENAME has."
2731 (car (cdr (file-attributes filename))))
2732
2733 (defun file-relative-name (filename &optional directory)
2734 "Convert FILENAME to be relative to DIRECTORY (default: `default-directory').
2735 This function returns a relative file name which is equivalent to FILENAME
2736 when used with that default directory as the default.
2737 If this is impossible (which can happen on MSDOS and Windows
2738 when the file name and directory use different drive names)
2739 then it returns FILENAME."
2740 (save-match-data
2741 (let ((fname (expand-file-name filename)))
2742 (setq directory (file-name-as-directory
2743 (expand-file-name (or directory default-directory))))
2744 ;; On Microsoft OSes, if FILENAME and DIRECTORY have different
2745 ;; drive names, they can't be relative, so return the absolute name.
2746 (if (and (or (eq system-type 'ms-dos)
2747 (eq system-type 'cygwin)
2748 (eq system-type 'windows-nt))
2749 (not (string-equal (substring fname 0 2)
2750 (substring directory 0 2))))
2751 filename
2752 (let ((ancestor ".")
2753 (fname-dir (file-name-as-directory fname)))
2754 (while (and (not (string-match (concat "^" (regexp-quote directory)) fname-dir))
2755 (not (string-match (concat "^" (regexp-quote directory)) fname)))
2756 (setq directory (file-name-directory (substring directory 0 -1))
2757 ancestor (if (equal ancestor ".")
2758 ".."
2759 (concat "../" ancestor))))
2760 ;; Now ancestor is empty, or .., or ../.., etc.
2761 (if (string-match (concat "^" (regexp-quote directory)) fname)
2762 ;; We matched within FNAME's directory part.
2763 ;; Add the rest of FNAME onto ANCESTOR.
2764 (let ((rest (substring fname (match-end 0))))
2765 (if (and (equal ancestor ".")
2766 (not (equal rest "")))
2767 ;; But don't bother with ANCESTOR if it would give us `./'.
2768 rest
2769 (concat (file-name-as-directory ancestor) rest)))
2770 ;; We matched FNAME's directory equivalent.
2771 ancestor))))))
2772 \f
2773 (defun save-buffer (&optional args)
2774 "Save current buffer in visited file if modified. Versions described below.
2775 By default, makes the previous version into a backup file
2776 if previously requested or if this is the first save.
2777 With 1 \\[universal-argument], marks this version
2778 to become a backup when the next save is done.
2779 With 2 \\[universal-argument]'s,
2780 unconditionally makes the previous version into a backup file.
2781 With 3 \\[universal-argument]'s, marks this version
2782 to become a backup when the next save is done,
2783 and unconditionally makes the previous version into a backup file.
2784
2785 With argument of 0, never make the previous version into a backup file.
2786
2787 If a file's name is FOO, the names of its numbered backup versions are
2788 FOO.~i~ for various integers i. A non-numbered backup file is called FOO~.
2789 Numeric backups (rather than FOO~) will be made if value of
2790 `version-control' is not the atom `never' and either there are already
2791 numeric versions of the file being backed up, or `version-control' is
2792 non-nil.
2793 We don't want excessive versions piling up, so there are variables
2794 `kept-old-versions', which tells Emacs how many oldest versions to keep,
2795 and `kept-new-versions', which tells how many newest versions to keep.
2796 Defaults are 2 old versions and 2 new.
2797 `dired-kept-versions' controls dired's clean-directory (.) command.
2798 If `delete-old-versions' is nil, system will query user
2799 before trimming versions. Otherwise it does it silently.
2800
2801 If `vc-make-backup-files' is nil, which is the default,
2802 no backup files are made for files managed by version control.
2803 (This is because the version control system itself records previous versions.)
2804
2805 See the subroutine `basic-save-buffer' for more information."
2806 (interactive "p")
2807 (let ((modp (buffer-modified-p))
2808 (large (> (buffer-size) 50000))
2809 (make-backup-files (or (and make-backup-files (not (eq args 0)))
2810 (memq args '(16 64)))))
2811 (and modp (memq args '(16 64)) (setq buffer-backed-up nil))
2812 (if (and modp large (buffer-file-name))
2813 (message "Saving file %s..." (buffer-file-name)))
2814 (basic-save-buffer)
2815 (and modp (memq args '(4 64)) (setq buffer-backed-up nil))))
2816
2817 (defun delete-auto-save-file-if-necessary (&optional force)
2818 "Delete auto-save file for current buffer if `delete-auto-save-files' is t.
2819 Normally delete only if the file was written by this Emacs since
2820 the last real save, but optional arg FORCE non-nil means delete anyway."
2821 (and buffer-auto-save-file-name delete-auto-save-files
2822 (not (string= buffer-file-name buffer-auto-save-file-name))
2823 (or force (recent-auto-save-p))
2824 (progn
2825 (condition-case ()
2826 (delete-file buffer-auto-save-file-name)
2827 (file-error nil))
2828 (set-buffer-auto-saved))))
2829
2830 (defvar auto-save-hook nil
2831 "Normal hook run just before auto-saving.")
2832
2833 (defcustom after-save-hook nil
2834 "Normal hook that is run after a buffer is saved to its file."
2835 :options '(executable-make-buffer-file-executable-if-script-p)
2836 :type 'hook
2837 :group 'files)
2838
2839 (defvar save-buffer-coding-system nil
2840 "If non-nil, use this coding system for saving the buffer.
2841 More precisely, use this coding system in place of the
2842 value of `buffer-file-coding-system', when saving the buffer.
2843 Calling `write-region' for any purpose other than saving the buffer
2844 will still use `buffer-file-coding-system'; this variable has no effect
2845 in such cases.")
2846
2847 (make-variable-buffer-local 'save-buffer-coding-system)
2848 (put 'save-buffer-coding-system 'permanent-local t)
2849
2850 (defun basic-save-buffer ()
2851 "Save the current buffer in its visited file, if it has been modified.
2852 The hooks `write-contents-functions' and `write-file-functions' get a chance
2853 to do the job of saving; if they do not, then the buffer is saved in
2854 the visited file file in the usual way.
2855 After saving the buffer, this function runs `after-save-hook'."
2856 (interactive)
2857 (save-current-buffer
2858 ;; In an indirect buffer, save its base buffer instead.
2859 (if (buffer-base-buffer)
2860 (set-buffer (buffer-base-buffer)))
2861 (if (buffer-modified-p)
2862 (let ((recent-save (recent-auto-save-p))
2863 setmodes tempsetmodes)
2864 ;; On VMS, rename file and buffer to get rid of version number.
2865 (if (and (eq system-type 'vax-vms)
2866 (not (string= buffer-file-name
2867 (file-name-sans-versions buffer-file-name))))
2868 (let (buffer-new-name)
2869 ;; Strip VMS version number before save.
2870 (setq buffer-file-name
2871 (file-name-sans-versions buffer-file-name))
2872 ;; Construct a (unique) buffer name to correspond.
2873 (let ((buf (create-file-buffer (downcase buffer-file-name))))
2874 (setq buffer-new-name (buffer-name buf))
2875 (kill-buffer buf))
2876 (rename-buffer buffer-new-name)))
2877 ;; If buffer has no file name, ask user for one.
2878 (or buffer-file-name
2879 (let ((filename
2880 (expand-file-name
2881 (read-file-name "File to save in: ") nil)))
2882 (and (file-exists-p filename)
2883 (or (y-or-n-p (format "File `%s' exists; overwrite? "
2884 filename))
2885 (error "Canceled")))
2886 (set-visited-file-name filename)))
2887 (or (verify-visited-file-modtime (current-buffer))
2888 (not (file-exists-p buffer-file-name))
2889 (yes-or-no-p
2890 (format "%s has changed since visited or saved. Save anyway? "
2891 (file-name-nondirectory buffer-file-name)))
2892 (error "Save not confirmed"))
2893 (save-restriction
2894 (widen)
2895 (save-excursion
2896 (and (> (point-max) (point-min))
2897 (not find-file-literally)
2898 (/= (char-after (1- (point-max))) ?\n)
2899 (not (and (eq selective-display t)
2900 (= (char-after (1- (point-max))) ?\r)))
2901 (or (eq require-final-newline t)
2902 (and require-final-newline
2903 (y-or-n-p
2904 (format "Buffer %s does not end in newline. Add one? "
2905 (buffer-name)))))
2906 (save-excursion
2907 (goto-char (point-max))
2908 (insert ?\n))))
2909 ;; Support VC version backups.
2910 (vc-before-save)
2911 (or (run-hook-with-args-until-success 'write-contents-functions)
2912 (run-hook-with-args-until-success 'local-write-file-hooks)
2913 (run-hook-with-args-until-success 'write-file-functions)
2914 ;; If a hook returned t, file is already "written".
2915 ;; Otherwise, write it the usual way now.
2916 (setq setmodes (basic-save-buffer-1)))
2917 ;; Now we have saved the current buffer. Let's make sure
2918 ;; that buffer-file-coding-system is fixed to what
2919 ;; actually used for saving by binding it locally.
2920 (if save-buffer-coding-system
2921 (setq save-buffer-coding-system last-coding-system-used)
2922 (setq buffer-file-coding-system last-coding-system-used))
2923 (setq buffer-file-number
2924 (nthcdr 10 (file-attributes buffer-file-name)))
2925 (if setmodes
2926 (condition-case ()
2927 (set-file-modes buffer-file-name (car setmodes))
2928 (error nil))))
2929 ;; If the auto-save file was recent before this command,
2930 ;; delete it now.
2931 (delete-auto-save-file-if-necessary recent-save)
2932 ;; Support VC `implicit' locking.
2933 (vc-after-save)
2934 (run-hooks 'after-save-hook))
2935 (message "(No changes need to be saved)"))))
2936
2937 ;; This does the "real job" of writing a buffer into its visited file
2938 ;; and making a backup file. This is what is normally done
2939 ;; but inhibited if one of write-file-functions returns non-nil.
2940 ;; It returns a value (MODES . BACKUPNAME), like backup-buffer.
2941 (defun basic-save-buffer-1 ()
2942 (if save-buffer-coding-system
2943 (let ((coding-system-for-write save-buffer-coding-system))
2944 (basic-save-buffer-2))
2945 (basic-save-buffer-2)))
2946
2947 ;; This returns a value (MODES . BACKUPNAME), like backup-buffer.
2948 (defun basic-save-buffer-2 ()
2949 (let (tempsetmodes setmodes)
2950 (if (not (file-writable-p buffer-file-name))
2951 (let ((dir (file-name-directory buffer-file-name)))
2952 (if (not (file-directory-p dir))
2953 (if (file-exists-p dir)
2954 (error "%s is not a directory" dir)
2955 (error "%s: no such directory" buffer-file-name))
2956 (if (not (file-exists-p buffer-file-name))
2957 (error "Directory %s write-protected" dir)
2958 (if (yes-or-no-p
2959 (format "File %s is write-protected; try to save anyway? "
2960 (file-name-nondirectory
2961 buffer-file-name)))
2962 (setq tempsetmodes t)
2963 (error "Attempt to save to a file which you aren't allowed to write"))))))
2964 (or buffer-backed-up
2965 (setq setmodes (backup-buffer)))
2966 (let ((dir (file-name-directory buffer-file-name)))
2967 (if (and file-precious-flag
2968 (file-writable-p dir))
2969 ;; If file is precious, write temp name, then rename it.
2970 ;; This requires write access to the containing dir,
2971 ;; which is why we don't try it if we don't have that access.
2972 (let ((realname buffer-file-name)
2973 tempname temp nogood i succeed
2974 (old-modtime (visited-file-modtime)))
2975 (setq i 0)
2976 (setq nogood t)
2977 ;; Find the temporary name to write under.
2978 (while nogood
2979 (setq tempname (format
2980 (if (and (eq system-type 'ms-dos)
2981 (not (msdos-long-file-names)))
2982 "%s#%d.tm#" ; MSDOS limits files to 8+3
2983 (if (memq system-type '(vax-vms axp-vms))
2984 "%s$tmp$%d"
2985 "%s#tmp#%d"))
2986 dir i))
2987 (setq nogood (file-exists-p tempname))
2988 (setq i (1+ i)))
2989 (unwind-protect
2990 (progn (clear-visited-file-modtime)
2991 (write-region (point-min) (point-max)
2992 tempname nil realname
2993 buffer-file-truename)
2994 (setq succeed t))
2995 ;; If writing the temp file fails,
2996 ;; delete the temp file.
2997 (or succeed
2998 (progn
2999 (condition-case nil
3000 (delete-file tempname)
3001 (file-error nil))
3002 (set-visited-file-modtime old-modtime))))
3003 ;; Since we have created an entirely new file
3004 ;; and renamed it, make sure it gets the
3005 ;; right permission bits set.
3006 (setq setmodes (or setmodes (cons (file-modes buffer-file-name)
3007 buffer-file-name)))
3008 ;; We succeeded in writing the temp file,
3009 ;; so rename it.
3010 (rename-file tempname buffer-file-name t))
3011 ;; If file not writable, see if we can make it writable
3012 ;; temporarily while we write it.
3013 ;; But no need to do so if we have just backed it up
3014 ;; (setmodes is set) because that says we're superseding.
3015 (cond ((and tempsetmodes (not setmodes))
3016 ;; Change the mode back, after writing.
3017 (setq setmodes (cons (file-modes buffer-file-name) buffer-file-name))
3018 (set-file-modes buffer-file-name (logior (car setmodes) 128))))
3019 (let (success)
3020 (unwind-protect
3021 (progn
3022 (write-region (point-min) (point-max)
3023 buffer-file-name nil t buffer-file-truename)
3024 (setq success t))
3025 ;; If we get an error writing the new file, and we made
3026 ;; the backup by renaming, undo the backing-up.
3027 (and setmodes (not success)
3028 (rename-file (cdr setmodes) buffer-file-name))))))
3029 setmodes))
3030
3031 (defun diff-buffer-with-file (&optional buffer)
3032 "View the differences between BUFFER and its associated file.
3033 This requires the external program `diff' to be in your `exec-path'."
3034 (interactive "bBuffer: ")
3035 (with-current-buffer (get-buffer (or buffer (current-buffer)))
3036 (if (and buffer-file-name
3037 (file-exists-p buffer-file-name))
3038 (let ((tempfile (make-temp-file "buffer-content-")))
3039 (unwind-protect
3040 (save-restriction
3041 (widen)
3042 (write-region (point-min) (point-max) tempfile nil 'nomessage)
3043 (diff buffer-file-name tempfile nil t)
3044 (sit-for 0))
3045 (when (file-exists-p tempfile)
3046 (delete-file tempfile))))
3047 (message "Buffer %s has no associated file on disc" (buffer-name))
3048 ;; Display that message for 1 second so that user can read it
3049 ;; in the minibuffer.
3050 (sit-for 1)))
3051 ;; return always nil, so that save-buffers-kill-emacs will not move
3052 ;; over to the next unsaved buffer when calling `d'.
3053 nil)
3054
3055 (defvar save-some-buffers-action-alist
3056 '((?\C-r
3057 (lambda (buf)
3058 (view-buffer buf
3059 (lambda (ignore)
3060 (exit-recursive-edit)))
3061 (recursive-edit)
3062 ;; Return nil to ask about BUF again.
3063 nil)
3064 "display the current buffer")
3065 (?d diff-buffer-with-file
3066 "show difference to last saved version"))
3067 "ACTION-ALIST argument used in call to `map-y-or-n-p'.")
3068 (put 'save-some-buffers-action-alist 'risky-local-variable t)
3069
3070 (defun save-some-buffers (&optional arg pred)
3071 "Save some modified file-visiting buffers. Asks user about each one.
3072 You can answer `y' to save, `n' not to save, `C-r' to look at the
3073 buffer in question with `view-buffer' before deciding or `d' to
3074 view the differences using `diff-buffer-to-file'.
3075
3076 Optional argument (the prefix) non-nil means save all with no questions.
3077 Optional second argument PRED determines which buffers are considered:
3078 If PRED is nil, all the file-visiting buffers are considered.
3079 If PRED is t, then certain non-file buffers will also be considered.
3080 If PRED is a zero-argument function, it indicates for each buffer whether
3081 to consider it or not when called with that buffer current.
3082
3083 See `save-some-buffers-action-alist' if you want to
3084 change the additional actions you can take on files."
3085 (interactive "P")
3086 (save-window-excursion
3087 (let* ((queried nil)
3088 (files-done
3089 (map-y-or-n-p
3090 (function
3091 (lambda (buffer)
3092 (and (buffer-modified-p buffer)
3093 (not (buffer-base-buffer buffer))
3094 (or
3095 (buffer-file-name buffer)
3096 (and pred
3097 (progn
3098 (set-buffer buffer)
3099 (and buffer-offer-save (> (buffer-size) 0)))))
3100 (or (not (functionp pred))
3101 (with-current-buffer buffer (funcall pred)))
3102 (if arg
3103 t
3104 (setq queried t)
3105 (if (buffer-file-name buffer)
3106 (format "Save file %s? "
3107 (buffer-file-name buffer))
3108 (format "Save buffer %s? "
3109 (buffer-name buffer)))))))
3110 (function
3111 (lambda (buffer)
3112 (set-buffer buffer)
3113 (save-buffer)))
3114 (buffer-list)
3115 '("buffer" "buffers" "save")
3116 save-some-buffers-action-alist))
3117 (abbrevs-done
3118 (and save-abbrevs abbrevs-changed
3119 (progn
3120 (if (or arg
3121 (eq save-abbrevs 'silently)
3122 (y-or-n-p (format "Save abbrevs in %s? "
3123 abbrev-file-name)))
3124 (write-abbrev-file nil))
3125 ;; Don't keep bothering user if he says no.
3126 (setq abbrevs-changed nil)
3127 t))))
3128 (or queried (> files-done 0) abbrevs-done
3129 (message "(No files need saving)")))))
3130 \f
3131 (defun not-modified (&optional arg)
3132 "Mark current buffer as unmodified, not needing to be saved.
3133 With prefix arg, mark buffer as modified, so \\[save-buffer] will save.
3134
3135 It is not a good idea to use this function in Lisp programs, because it
3136 prints a message in the minibuffer. Instead, use `set-buffer-modified-p'."
3137 (interactive "P")
3138 (message (if arg "Modification-flag set"
3139 "Modification-flag cleared"))
3140 (set-buffer-modified-p arg))
3141
3142 (defun toggle-read-only (&optional arg)
3143 "Change whether this buffer is visiting its file read-only.
3144 With arg, set read-only iff arg is positive.
3145 If visiting file read-only and `view-read-only' is non-nil, enter view mode."
3146 (interactive "P")
3147 (if (and arg
3148 (if (> (prefix-numeric-value arg) 0) buffer-read-only
3149 (not buffer-read-only))) ; If buffer-read-only is set correctly,
3150 nil ; do nothing.
3151 ;; Toggle.
3152 (cond
3153 ((and buffer-read-only view-mode)
3154 (View-exit-and-edit)
3155 (make-local-variable 'view-read-only)
3156 (setq view-read-only t)) ; Must leave view mode.
3157 ((and (not buffer-read-only) view-read-only
3158 (not (eq (get major-mode 'mode-class) 'special)))
3159 (view-mode-enter))
3160 (t (setq buffer-read-only (not buffer-read-only))
3161 (force-mode-line-update)))
3162 (if (vc-backend buffer-file-name)
3163 (message (substitute-command-keys
3164 (concat "File is under version-control; "
3165 "use \\[vc-next-action] to check in/out"))))))
3166
3167 (defun insert-file (filename)
3168 "Insert contents of file FILENAME into buffer after point.
3169 Set mark after the inserted text.
3170
3171 This function is meant for the user to run interactively.
3172 Don't call it from programs! Use `insert-file-contents' instead.
3173 \(Its calling sequence is different; see its documentation)."
3174 (interactive "*fInsert file: ")
3175 (insert-file-1 filename #'insert-file-contents))
3176
3177 (defun append-to-file (start end filename)
3178 "Append the contents of the region to the end of file FILENAME.
3179 When called from a function, expects three arguments,
3180 START, END and FILENAME. START and END are buffer positions
3181 saying what text to write."
3182 (interactive "r\nFAppend to file: ")
3183 (write-region start end filename t))
3184
3185 (defun file-newest-backup (filename)
3186 "Return most recent backup file for FILENAME or nil if no backups exist."
3187 ;; `make-backup-file-name' will get us the right directory for
3188 ;; ordinary or numeric backups. It might create a directory for
3189 ;; backups as a side-effect, according to `backup-directory-alist'.
3190 (let* ((filename (file-name-sans-versions
3191 (make-backup-file-name filename)))
3192 (file (file-name-nondirectory filename))
3193 (dir (file-name-directory filename))
3194 (comp (file-name-all-completions file dir))
3195 (newest nil)
3196 tem)
3197 (while comp
3198 (setq tem (pop comp))
3199 (cond ((and (backup-file-name-p tem)
3200 (string= (file-name-sans-versions tem) file))
3201 (setq tem (concat dir tem))
3202 (if (or (null newest)
3203 (file-newer-than-file-p tem newest))
3204 (setq newest tem)))))
3205 newest))
3206
3207 (defun rename-uniquely ()
3208 "Rename current buffer to a similar name not already taken.
3209 This function is useful for creating multiple shell process buffers
3210 or multiple mail buffers, etc."
3211 (interactive)
3212 (save-match-data
3213 (let ((base-name (buffer-name)))
3214 (and (string-match "<[0-9]+>\\'" base-name)
3215 (not (and buffer-file-name
3216 (string= base-name
3217 (file-name-nondirectory buffer-file-name))))
3218 ;; If the existing buffer name has a <NNN>,
3219 ;; which isn't part of the file name (if any),
3220 ;; then get rid of that.
3221 (setq base-name (substring base-name 0 (match-beginning 0))))
3222 (rename-buffer (generate-new-buffer-name base-name))
3223 (force-mode-line-update))))
3224
3225 (defun make-directory (dir &optional parents)
3226 "Create the directory DIR and any nonexistent parent dirs.
3227 Interactively, the default choice of directory to create
3228 is the current default directory for file names.
3229 That is useful when you have visited a file in a nonexistent directory.
3230
3231 Noninteractively, the second (optional) argument PARENTS says whether
3232 to create parent directories if they don't exist."
3233 (interactive
3234 (list (read-file-name "Make directory: " default-directory default-directory
3235 nil nil)
3236 t))
3237 ;; If default-directory is a remote directory,
3238 ;; make sure we find its make-directory handler.
3239 (setq dir (expand-file-name dir))
3240 (let ((handler (find-file-name-handler dir 'make-directory)))
3241 (if handler
3242 (funcall handler 'make-directory dir parents)
3243 (if (not parents)
3244 (make-directory-internal dir)
3245 (let ((dir (directory-file-name (expand-file-name dir)))
3246 create-list)
3247 (while (not (file-exists-p dir))
3248 (setq create-list (cons dir create-list)
3249 dir (directory-file-name (file-name-directory dir))))
3250 (while create-list
3251 (make-directory-internal (car create-list))
3252 (setq create-list (cdr create-list))))))))
3253 \f
3254 (put 'revert-buffer-function 'permanent-local t)
3255 (defvar revert-buffer-function nil
3256 "Function to use to revert this buffer, or nil to do the default.
3257 The function receives two arguments IGNORE-AUTO and NOCONFIRM,
3258 which are the arguments that `revert-buffer' received.")
3259
3260 (put 'revert-buffer-insert-file-contents-function 'permanent-local t)
3261 (defvar revert-buffer-insert-file-contents-function nil
3262 "Function to use to insert contents when reverting this buffer.
3263 Gets two args, first the nominal file name to use,
3264 and second, t if reading the auto-save file.
3265
3266 The function you specify is responsible for updating (or preserving) point.")
3267
3268 (defvar before-revert-hook nil
3269 "Normal hook for `revert-buffer' to run before reverting.
3270 If `revert-buffer-function' is used to override the normal revert
3271 mechanism, this hook is not used.")
3272
3273 (defvar after-revert-hook nil
3274 "Normal hook for `revert-buffer' to run after reverting.
3275 Note that the hook value that it runs is the value that was in effect
3276 before reverting; that makes a difference if you have buffer-local
3277 hook functions.
3278
3279 If `revert-buffer-function' is used to override the normal revert
3280 mechanism, this hook is not used.")
3281
3282 (defvar revert-buffer-internal-hook)
3283
3284 (defun revert-buffer (&optional ignore-auto noconfirm preserve-modes)
3285 "Replace current buffer text with the text of the visited file on disk.
3286 This undoes all changes since the file was visited or saved.
3287 With a prefix argument, offer to revert from latest auto-save file, if
3288 that is more recent than the visited file.
3289
3290 This command also works for special buffers that contain text which
3291 doesn't come from a file, but reflects some other data base instead:
3292 for example, Dired buffers and buffer-list buffers. In these cases,
3293 it reconstructs the buffer contents from the appropriate data base.
3294
3295 When called from Lisp, the first argument is IGNORE-AUTO; only offer
3296 to revert from the auto-save file when this is nil. Note that the
3297 sense of this argument is the reverse of the prefix argument, for the
3298 sake of backward compatibility. IGNORE-AUTO is optional, defaulting
3299 to nil.
3300
3301 Optional second argument NOCONFIRM means don't ask for confirmation at
3302 all. (The local variable `revert-without-query', if non-nil, prevents
3303 confirmation.)
3304
3305 Optional third argument PRESERVE-MODES non-nil means don't alter
3306 the files modes. Normally we reinitialize them using `normal-mode'.
3307
3308 If the value of `revert-buffer-function' is non-nil, it is called to
3309 do all the work for this command. Otherwise, the hooks
3310 `before-revert-hook' and `after-revert-hook' are run at the beginning
3311 and the end, and if `revert-buffer-insert-file-contents-function' is
3312 non-nil, it is called instead of rereading visited file contents."
3313
3314 ;; I admit it's odd to reverse the sense of the prefix argument, but
3315 ;; there is a lot of code out there which assumes that the first
3316 ;; argument should be t to avoid consulting the auto-save file, and
3317 ;; there's no straightforward way to encourage authors to notice a
3318 ;; reversal of the argument sense. So I'm just changing the user
3319 ;; interface, but leaving the programmatic interface the same.
3320 (interactive (list (not current-prefix-arg)))
3321 (if revert-buffer-function
3322 (funcall revert-buffer-function ignore-auto noconfirm)
3323 (let* ((auto-save-p (and (not ignore-auto)
3324 (recent-auto-save-p)
3325 buffer-auto-save-file-name
3326 (file-readable-p buffer-auto-save-file-name)
3327 (y-or-n-p
3328 "Buffer has been auto-saved recently. Revert from auto-save file? ")))
3329 (file-name (if auto-save-p
3330 buffer-auto-save-file-name
3331 buffer-file-name)))
3332 (cond ((null file-name)
3333 (error "Buffer does not seem to be associated with any file"))
3334 ((or noconfirm
3335 (and (not (buffer-modified-p))
3336 (let ((tail revert-without-query)
3337 (found nil))
3338 (while tail
3339 (if (string-match (car tail) file-name)
3340 (setq found t))
3341 (setq tail (cdr tail)))
3342 found))
3343 (yes-or-no-p (format "Revert buffer from file %s? "
3344 file-name)))
3345 (run-hooks 'before-revert-hook)
3346 ;; If file was backed up but has changed since,
3347 ;; we shd make another backup.
3348 (and (not auto-save-p)
3349 (not (verify-visited-file-modtime (current-buffer)))
3350 (setq buffer-backed-up nil))
3351 ;; Get rid of all undo records for this buffer.
3352 (or (eq buffer-undo-list t)
3353 (setq buffer-undo-list nil))
3354 ;; Effectively copy the after-revert-hook status,
3355 ;; since after-find-file will clobber it.
3356 (let ((global-hook (default-value 'after-revert-hook))
3357 (local-hook-p (local-variable-p 'after-revert-hook))
3358 (local-hook (and (local-variable-p 'after-revert-hook)
3359 after-revert-hook)))
3360 (let (buffer-read-only
3361 ;; Don't make undo records for the reversion.
3362 (buffer-undo-list t))
3363 (if revert-buffer-insert-file-contents-function
3364 (funcall revert-buffer-insert-file-contents-function
3365 file-name auto-save-p)
3366 (if (not (file-exists-p file-name))
3367 (error "File %s no longer exists!" file-name))
3368 ;; Bind buffer-file-name to nil
3369 ;; so that we don't try to lock the file.
3370 (let ((buffer-file-name nil))
3371 (or auto-save-p
3372 (unlock-buffer)))
3373 (widen)
3374 (let ((coding-system-for-read
3375 ;; Auto-saved file shoule be read without
3376 ;; any code conversion.
3377 (if auto-save-p 'emacs-mule-unix
3378 (or coding-system-for-read
3379 buffer-file-coding-system))))
3380 ;; This force
3381 ;; after-insert-file-set-buffer-file-coding-system
3382 ;; (called from insert-file-contents) to set
3383 ;; buffer-file-coding-system to a proper value.
3384 (kill-local-variable 'buffer-file-coding-system)
3385
3386 ;; Note that this preserves point in an intelligent way.
3387 (if preserve-modes
3388 (let ((buffer-file-format buffer-file-format))
3389 (insert-file-contents file-name (not auto-save-p)
3390 nil nil t))
3391 (insert-file-contents file-name (not auto-save-p)
3392 nil nil t)))))
3393 ;; Recompute the truename in case changes in symlinks
3394 ;; have changed the truename.
3395 (setq buffer-file-truename
3396 (abbreviate-file-name (file-truename buffer-file-name)))
3397 (after-find-file nil nil t t preserve-modes)
3398 ;; Run after-revert-hook as it was before we reverted.
3399 (setq-default revert-buffer-internal-hook global-hook)
3400 (if local-hook-p
3401 (progn
3402 (make-local-variable 'revert-buffer-internal-hook)
3403 (setq revert-buffer-internal-hook local-hook))
3404 (kill-local-variable 'revert-buffer-internal-hook))
3405 (run-hooks 'revert-buffer-internal-hook))
3406 t)))))
3407
3408 (defun recover-this-file ()
3409 "Recover the visited file--get contents from its last auto-save file."
3410 (interactive)
3411 (recover-file buffer-file-name))
3412
3413 (defun recover-file (file)
3414 "Visit file FILE, but get contents from its last auto-save file."
3415 ;; Actually putting the file name in the minibuffer should be used
3416 ;; only rarely.
3417 ;; Not just because users often use the default.
3418 (interactive "FRecover file: ")
3419 (setq file (expand-file-name file))
3420 (if (auto-save-file-name-p (file-name-nondirectory file))
3421 (error "%s is an auto-save file" file))
3422 (let ((file-name (let ((buffer-file-name file))
3423 (make-auto-save-file-name))))
3424 (cond ((if (file-exists-p file)
3425 (not (file-newer-than-file-p file-name file))
3426 (not (file-exists-p file-name)))
3427 (error "Auto-save file %s not current" file-name))
3428 ((save-window-excursion
3429 (with-output-to-temp-buffer "*Directory*"
3430 (buffer-disable-undo standard-output)
3431 (save-excursion
3432 (let ((switches dired-listing-switches))
3433 (if (file-symlink-p file)
3434 (setq switches (concat switches "L")))
3435 (set-buffer standard-output)
3436 ;; Use insert-directory-safely, not insert-directory,
3437 ;; because these files might not exist. In particular,
3438 ;; FILE might not exist if the auto-save file was for
3439 ;; a buffer that didn't visit a file, such as "*mail*".
3440 ;; The code in v20.x called `ls' directly, so we need
3441 ;; to emulate what `ls' did in that case.
3442 (insert-directory-safely file switches)
3443 (insert-directory-safely file-name switches))))
3444 (yes-or-no-p (format "Recover auto save file %s? " file-name)))
3445 (switch-to-buffer (find-file-noselect file t))
3446 (let ((buffer-read-only nil)
3447 ;; Keep the current buffer-file-coding-system.
3448 (coding-system buffer-file-coding-system)
3449 ;; Auto-saved file shoule be read without any code conversion.
3450 (coding-system-for-read 'emacs-mule-unix))
3451 (erase-buffer)
3452 (insert-file-contents file-name nil)
3453 (set-buffer-file-coding-system coding-system))
3454 (after-find-file nil nil t))
3455 (t (error "Recover-file cancelled")))))
3456
3457 (defun recover-session ()
3458 "Recover auto save files from a previous Emacs session.
3459 This command first displays a Dired buffer showing you the
3460 previous sessions that you could recover from.
3461 To choose one, move point to the proper line and then type C-c C-c.
3462 Then you'll be asked about a number of files to recover."
3463 (interactive)
3464 (if (null auto-save-list-file-prefix)
3465 (error "You set `auto-save-list-file-prefix' to disable making session files"))
3466 (let ((dir (file-name-directory auto-save-list-file-prefix)))
3467 (unless (file-directory-p dir)
3468 (make-directory dir t)))
3469 (let ((ls-lisp-support-shell-wildcards t))
3470 (dired (concat auto-save-list-file-prefix "*")
3471 (concat dired-listing-switches "t")))
3472 (save-excursion
3473 (goto-char (point-min))
3474 (or (looking-at " Move to the session you want to recover,")
3475 (let ((inhibit-read-only t))
3476 ;; Each line starts with a space
3477 ;; so that Font Lock mode won't highlight the first character.
3478 (insert " Move to the session you want to recover,\n"
3479 " then type C-c C-c to select it.\n\n"
3480 " You can also delete some of these files;\n"
3481 " type d on a line to mark that file for deletion.\n\n"))))
3482 (use-local-map (nconc (make-sparse-keymap) (current-local-map)))
3483 (define-key (current-local-map) "\C-c\C-c" 'recover-session-finish))
3484
3485 (defun recover-session-finish ()
3486 "Choose one saved session to recover auto-save files from.
3487 This command is used in the special Dired buffer created by
3488 \\[recover-session]."
3489 (interactive)
3490 ;; Get the name of the session file to recover from.
3491 (let ((file (dired-get-filename))
3492 files
3493 (buffer (get-buffer-create " *recover*")))
3494 (dired-unmark 1)
3495 (dired-do-flagged-delete t)
3496 (unwind-protect
3497 (save-excursion
3498 ;; Read in the auto-save-list file.
3499 (set-buffer buffer)
3500 (erase-buffer)
3501 (insert-file-contents file)
3502 ;; Loop thru the text of that file
3503 ;; and get out the names of the files to recover.
3504 (while (not (eobp))
3505 (let (thisfile autofile)
3506 (if (eolp)
3507 ;; This is a pair of lines for a non-file-visiting buffer.
3508 ;; Get the auto-save file name and manufacture
3509 ;; a "visited file name" from that.
3510 (progn
3511 (forward-line 1)
3512 (setq autofile
3513 (buffer-substring-no-properties
3514 (point)
3515 (save-excursion
3516 (end-of-line)
3517 (point))))
3518 (setq thisfile
3519 (expand-file-name
3520 (substring
3521 (file-name-nondirectory autofile)
3522 1 -1)
3523 (file-name-directory autofile)))
3524 (forward-line 1))
3525 ;; This pair of lines is a file-visiting
3526 ;; buffer. Use the visited file name.
3527 (progn
3528 (setq thisfile
3529 (buffer-substring-no-properties
3530 (point) (progn (end-of-line) (point))))
3531 (forward-line 1)
3532 (setq autofile
3533 (buffer-substring-no-properties
3534 (point) (progn (end-of-line) (point))))
3535 (forward-line 1)))
3536 ;; Ignore a file if its auto-save file does not exist now.
3537 (if (file-exists-p autofile)
3538 (setq files (cons thisfile files)))))
3539 (setq files (nreverse files))
3540 ;; The file contains a pair of line for each auto-saved buffer.
3541 ;; The first line of the pair contains the visited file name
3542 ;; or is empty if the buffer was not visiting a file.
3543 ;; The second line is the auto-save file name.
3544 (if files
3545 (map-y-or-n-p "Recover %s? "
3546 (lambda (file)
3547 (condition-case nil
3548 (save-excursion (recover-file file))
3549 (error
3550 "Failed to recover `%s'" file)))
3551 files
3552 '("file" "files" "recover"))
3553 (message "No files can be recovered from this session now")))
3554 (kill-buffer buffer))))
3555
3556 (defun kill-some-buffers (&optional list)
3557 "For each buffer in LIST, ask whether to kill it.
3558 LIST defaults to all existing live buffers."
3559 (interactive)
3560 (if (null list)
3561 (setq list (buffer-list)))
3562 (while list
3563 (let* ((buffer (car list))
3564 (name (buffer-name buffer)))
3565 (and (not (string-equal name ""))
3566 (/= (aref name 0) ? )
3567 (yes-or-no-p
3568 (format "Buffer %s %s. Kill? "
3569 name
3570 (if (buffer-modified-p buffer)
3571 "HAS BEEN EDITED" "is unmodified")))
3572 (kill-buffer buffer)))
3573 (setq list (cdr list))))
3574 \f
3575 (defun auto-save-mode (arg)
3576 "Toggle auto-saving of contents of current buffer.
3577 With prefix argument ARG, turn auto-saving on if positive, else off."
3578 (interactive "P")
3579 (setq buffer-auto-save-file-name
3580 (and (if (null arg)
3581 (or (not buffer-auto-save-file-name)
3582 ;; If auto-save is off because buffer has shrunk,
3583 ;; then toggling should turn it on.
3584 (< buffer-saved-size 0))
3585 (or (eq arg t) (listp arg) (and (integerp arg) (> arg 0))))
3586 (if (and buffer-file-name auto-save-visited-file-name
3587 (not buffer-read-only))
3588 buffer-file-name
3589 (make-auto-save-file-name))))
3590 ;; If -1 was stored here, to temporarily turn off saving,
3591 ;; turn it back on.
3592 (and (< buffer-saved-size 0)
3593 (setq buffer-saved-size 0))
3594 (if (interactive-p)
3595 (message "Auto-save %s (in this buffer)"
3596 (if buffer-auto-save-file-name "on" "off")))
3597 buffer-auto-save-file-name)
3598
3599 (defun rename-auto-save-file ()
3600 "Adjust current buffer's auto save file name for current conditions.
3601 Also rename any existing auto save file, if it was made in this session."
3602 (let ((osave buffer-auto-save-file-name))
3603 (setq buffer-auto-save-file-name
3604 (make-auto-save-file-name))
3605 (if (and osave buffer-auto-save-file-name
3606 (not (string= buffer-auto-save-file-name buffer-file-name))
3607 (not (string= buffer-auto-save-file-name osave))
3608 (file-exists-p osave)
3609 (recent-auto-save-p))
3610 (rename-file osave buffer-auto-save-file-name t))))
3611
3612 (defun make-auto-save-file-name ()
3613 "Return file name to use for auto-saves of current buffer.
3614 Does not consider `auto-save-visited-file-name' as that variable is checked
3615 before calling this function. You can redefine this for customization.
3616 See also `auto-save-file-name-p'."
3617 (if buffer-file-name
3618 (let ((list auto-save-file-name-transforms)
3619 (filename buffer-file-name)
3620 result uniq)
3621 ;; Apply user-specified translations
3622 ;; to the file name.
3623 (while (and list (not result))
3624 (if (string-match (car (car list)) filename)
3625 (setq result (replace-match (cadr (car list)) t nil
3626 filename)
3627 uniq (car (cddr (car list)))))
3628 (setq list (cdr list)))
3629 (if result
3630 (if uniq
3631 (setq filename (concat
3632 (file-name-directory result)
3633 (subst-char-in-string
3634 ?/ ?!
3635 (replace-regexp-in-string "!" "!!"
3636 filename))))
3637 (setq filename result)))
3638 (setq result
3639 (if (and (eq system-type 'ms-dos)
3640 (not (msdos-long-file-names)))
3641 ;; We truncate the file name to DOS 8+3 limits
3642 ;; before doing anything else, because the regexp
3643 ;; passed to string-match below cannot handle
3644 ;; extensions longer than 3 characters, multiple
3645 ;; dots, and other atrocities.
3646 (let ((fn (dos-8+3-filename
3647 (file-name-nondirectory buffer-file-name))))
3648 (string-match
3649 "\\`\\([^.]+\\)\\(\\.\\(..?\\)?.?\\|\\)\\'"
3650 fn)
3651 (concat (file-name-directory buffer-file-name)
3652 "#" (match-string 1 fn)
3653 "." (match-string 3 fn) "#"))
3654 (concat (file-name-directory filename)
3655 "#"
3656 (file-name-nondirectory filename)
3657 "#")))
3658 ;; Make sure auto-save file names don't contain characters
3659 ;; invalid for the underlying filesystem.
3660 (if (and (memq system-type '(ms-dos windows-nt))
3661 ;; Don't modify remote (ange-ftp) filenames
3662 (not (string-match "^/\\w+@[-A-Za-z0-9._]+:" result)))
3663 (convert-standard-filename result)
3664 result))
3665
3666 ;; Deal with buffers that don't have any associated files. (Mail
3667 ;; mode tends to create a good number of these.)
3668
3669 (let ((buffer-name (buffer-name))
3670 (limit 0)
3671 file-name)
3672 ;; Eliminate all slashes and backslashes by
3673 ;; replacing them with sequences that start with %.
3674 ;; Quote % also, to keep distinct names distinct.
3675 (while (string-match "[/\\%]" buffer-name limit)
3676 (let* ((character (aref buffer-name (match-beginning 0)))
3677 (replacement
3678 (cond ((eq character ?%) "%%")
3679 ((eq character ?/) "%+")
3680 ((eq character ?\\) "%-"))))
3681 (setq buffer-name (replace-match replacement t t buffer-name))
3682 (setq limit (1+ (match-end 0)))))
3683 ;; Generate the file name.
3684 (setq file-name
3685 (make-temp-file
3686 (let ((fname
3687 (expand-file-name
3688 (format "#%s#" buffer-name)
3689 ;; Try a few alternative directories, to get one we can
3690 ;; write it.
3691 (cond
3692 ((file-writable-p default-directory) default-directory)
3693 ((file-writable-p "/var/tmp/") "/var/tmp/")
3694 ("~/")))))
3695 (if (and (memq system-type '(ms-dos windows-nt))
3696 ;; Don't modify remote (ange-ftp) filenames
3697 (not (string-match "^/\\w+@[-A-Za-z0-9._]+:" fname)))
3698 ;; The call to convert-standard-filename is in case
3699 ;; buffer-name includes characters not allowed by the
3700 ;; DOS/Windows filesystems. make-temp-file writes to the
3701 ;; file it creates, so we must fix the file name _before_
3702 ;; make-temp-file is called.
3703 (convert-standard-filename fname)
3704 fname))
3705 nil "#"))
3706 ;; make-temp-file creates the file,
3707 ;; but we don't want it to exist until we do an auto-save.
3708 (condition-case ()
3709 (delete-file file-name)
3710 (file-error nil))
3711 file-name)))
3712
3713 (defun auto-save-file-name-p (filename)
3714 "Return non-nil if FILENAME can be yielded by `make-auto-save-file-name'.
3715 FILENAME should lack slashes. You can redefine this for customization."
3716 (string-match "^#.*#$" filename))
3717 \f
3718 (defun wildcard-to-regexp (wildcard)
3719 "Given a shell file name pattern WILDCARD, return an equivalent regexp.
3720 The generated regexp will match a filename iff the filename
3721 matches that wildcard according to shell rules. Only wildcards known
3722 by `sh' are supported."
3723 (let* ((i (string-match "[[.*+\\^$?]" wildcard))
3724 ;; Copy the initial run of non-special characters.
3725 (result (substring wildcard 0 i))
3726 (len (length wildcard)))
3727 ;; If no special characters, we're almost done.
3728 (if i
3729 (while (< i len)
3730 (let ((ch (aref wildcard i))
3731 j)
3732 (setq
3733 result
3734 (concat result
3735 (cond
3736 ((and (eq ch ?\[)
3737 (< (1+ i) len)
3738 (eq (aref wildcard (1+ i)) ?\]))
3739 "\\[")
3740 ((eq ch ?\[) ; [...] maps to regexp char class
3741 (progn
3742 (setq i (1+ i))
3743 (concat
3744 (cond
3745 ((eq (aref wildcard i) ?!) ; [!...] -> [^...]
3746 (progn
3747 (setq i (1+ i))
3748 (if (eq (aref wildcard i) ?\])
3749 (progn
3750 (setq i (1+ i))
3751 "[^]")
3752 "[^")))
3753 ((eq (aref wildcard i) ?^)
3754 ;; Found "[^". Insert a `\0' character
3755 ;; (which cannot happen in a filename)
3756 ;; into the character class, so that `^'
3757 ;; is not the first character after `[',
3758 ;; and thus non-special in a regexp.
3759 (progn
3760 (setq i (1+ i))
3761 "[\000^"))
3762 ((eq (aref wildcard i) ?\])
3763 ;; I don't think `]' can appear in a
3764 ;; character class in a wildcard, but
3765 ;; let's be general here.
3766 (progn
3767 (setq i (1+ i))
3768 "[]"))
3769 (t "["))
3770 (prog1 ; copy everything upto next `]'.
3771 (substring wildcard
3772 i
3773 (setq j (string-match
3774 "]" wildcard i)))
3775 (setq i (if j (1- j) (1- len)))))))
3776 ((eq ch ?.) "\\.")
3777 ((eq ch ?*) "[^\000]*")
3778 ((eq ch ?+) "\\+")
3779 ((eq ch ?^) "\\^")
3780 ((eq ch ?$) "\\$")
3781 ((eq ch ?\\) "\\\\") ; probably cannot happen...
3782 ((eq ch ??) "[^\000]")
3783 (t (char-to-string ch)))))
3784 (setq i (1+ i)))))
3785 ;; Shell wildcards should match the entire filename,
3786 ;; not its part. Make the regexp say so.
3787 (concat "\\`" result "\\'")))
3788 \f
3789 (defcustom list-directory-brief-switches
3790 (if (eq system-type 'vax-vms) "" "-CF")
3791 "*Switches for `list-directory' to pass to `ls' for brief listing."
3792 :type 'string
3793 :group 'dired)
3794
3795 (defcustom list-directory-verbose-switches
3796 (if (eq system-type 'vax-vms)
3797 "/PROTECTION/SIZE/DATE/OWNER/WIDTH=(OWNER:10)"
3798 "-l")
3799 "*Switches for `list-directory' to pass to `ls' for verbose listing."
3800 :type 'string
3801 :group 'dired)
3802
3803 (defun file-expand-wildcards (pattern &optional full)
3804 "Expand wildcard pattern PATTERN.
3805 This returns a list of file names which match the pattern.
3806
3807 If PATTERN is written as an absolute relative file name,
3808 the values are absolute also.
3809
3810 If PATTERN is written as a relative file name, it is interpreted
3811 relative to the current default directory, `default-directory'.
3812 The file names returned are normally also relative to the current
3813 default directory. However, if FULL is non-nil, they are absolute."
3814 (save-match-data
3815 (let* ((nondir (file-name-nondirectory pattern))
3816 (dirpart (file-name-directory pattern))
3817 ;; A list of all dirs that DIRPART specifies.
3818 ;; This can be more than one dir
3819 ;; if DIRPART contains wildcards.
3820 (dirs (if (and dirpart (string-match "[[*?]" dirpart))
3821 (mapcar 'file-name-as-directory
3822 (file-expand-wildcards (directory-file-name dirpart)))
3823 (list dirpart)))
3824 contents)
3825 (while dirs
3826 (when (or (null (car dirs)) ; Possible if DIRPART is not wild.
3827 (file-directory-p (directory-file-name (car dirs))))
3828 (let ((this-dir-contents
3829 ;; Filter out "." and ".."
3830 (delq nil
3831 (mapcar #'(lambda (name)
3832 (unless (string-match "\\`\\.\\.?\\'"
3833 (file-name-nondirectory name))
3834 name))
3835 (directory-files (or (car dirs) ".") full
3836 (wildcard-to-regexp nondir))))))
3837 (setq contents
3838 (nconc
3839 (if (and (car dirs) (not full))
3840 (mapcar (function (lambda (name) (concat (car dirs) name)))
3841 this-dir-contents)
3842 this-dir-contents)
3843 contents))))
3844 (setq dirs (cdr dirs)))
3845 contents)))
3846
3847 (defun list-directory (dirname &optional verbose)
3848 "Display a list of files in or matching DIRNAME, a la `ls'.
3849 DIRNAME is globbed by the shell if necessary.
3850 Prefix arg (second arg if noninteractive) means supply -l switch to `ls'.
3851 Actions controlled by variables `list-directory-brief-switches'
3852 and `list-directory-verbose-switches'."
3853 (interactive (let ((pfx current-prefix-arg))
3854 (list (read-file-name (if pfx "List directory (verbose): "
3855 "List directory (brief): ")
3856 nil default-directory nil)
3857 pfx)))
3858 (let ((switches (if verbose list-directory-verbose-switches
3859 list-directory-brief-switches))
3860 buffer)
3861 (or dirname (setq dirname default-directory))
3862 (setq dirname (expand-file-name dirname))
3863 (with-output-to-temp-buffer "*Directory*"
3864 (setq buffer standard-output)
3865 (buffer-disable-undo standard-output)
3866 (princ "Directory ")
3867 (princ dirname)
3868 (terpri)
3869 (save-excursion
3870 (set-buffer "*Directory*")
3871 (let ((wildcard (not (file-directory-p dirname))))
3872 (insert-directory dirname switches wildcard (not wildcard)))))
3873 ;; Finishing with-output-to-temp-buffer seems to clobber default-directory.
3874 (with-current-buffer buffer
3875 (setq default-directory
3876 (if (file-directory-p dirname)
3877 (file-name-as-directory dirname)
3878 (file-name-directory dirname))))))
3879
3880 (defun shell-quote-wildcard-pattern (pattern)
3881 "Quote characters special to the shell in PATTERN, leave wildcards alone.
3882
3883 PATTERN is assumed to represent a file-name wildcard suitable for the
3884 underlying filesystem. For Unix and GNU/Linux, the characters from the
3885 set [ \\t\\n;<>&|()#$] are quoted with a backslash; for DOS/Windows, all
3886 the parts of the pattern which don't include wildcard characters are
3887 quoted with double quotes.
3888 Existing quote characters in PATTERN are left alone, so you can pass
3889 PATTERN that already quotes some of the special characters."
3890 (save-match-data
3891 (cond
3892 ((memq system-type '(ms-dos windows-nt cygwin))
3893 ;; DOS/Windows don't allow `"' in file names. So if the
3894 ;; argument has quotes, we can safely assume it is already
3895 ;; quoted by the caller.
3896 (if (or (string-match "[\"]" pattern)
3897 ;; We quote [&()#$'] in case their shell is a port of a
3898 ;; Unixy shell. We quote [,=+] because stock DOS and
3899 ;; Windows shells require that in some cases, such as
3900 ;; passing arguments to batch files that use positional
3901 ;; arguments like %1.
3902 (not (string-match "[ \t;&()#$',=+]" pattern)))
3903 pattern
3904 (let ((result "\"")
3905 (beg 0)
3906 end)
3907 (while (string-match "[*?]+" pattern beg)
3908 (setq end (match-beginning 0)
3909 result (concat result (substring pattern beg end)
3910 "\""
3911 (substring pattern end (match-end 0))
3912 "\"")
3913 beg (match-end 0)))
3914 (concat result (substring pattern beg) "\""))))
3915 (t
3916 (let ((beg 0))
3917 (while (string-match "[ \t\n;<>&|()#$]" pattern beg)
3918 (setq pattern
3919 (concat (substring pattern 0 (match-beginning 0))
3920 "\\"
3921 (substring pattern (match-beginning 0)))
3922 beg (1+ (match-end 0)))))
3923 pattern))))
3924
3925
3926 (defvar insert-directory-program "ls"
3927 "Absolute or relative name of the `ls' program used by `insert-directory'.")
3928
3929 (defcustom directory-free-space-program "df"
3930 "*Program to get the amount of free space on a file system.
3931 We assume the output has the format of `df'.
3932 The value of this variable must be just a command name or file name;
3933 if you want to specify options, use `directory-free-space-args'.
3934
3935 A value of nil disables this feature.
3936
3937 If the function `file-system-info' is defined, it is always used in
3938 preference to the program given by this variable."
3939 :type '(choice (string :tag "Program") (const :tag "None" nil))
3940 :group 'dired)
3941
3942 (defcustom directory-free-space-args
3943 (if (eq system-type 'darwin) "-k" "-Pk")
3944 "*Options to use when running `directory-free-space-program'."
3945 :type 'string
3946 :group 'dired)
3947
3948 (defun get-free-disk-space (dir)
3949 "Return the mount of free space on directory DIR's file system.
3950 The result is a string that gives the number of free 1KB blocks,
3951 or nil if the system call or the program which retrieve the infornmation
3952 fail.
3953
3954 This function calls `file-system-info' if it is available, or invokes the
3955 program specified by `directory-free-space-program' if that is non-nil."
3956 ;; Try to find the number of free blocks. Non-Posix systems don't
3957 ;; always have df, but might have an equivalent system call.
3958 (if (fboundp 'file-system-info)
3959 (let ((fsinfo (file-system-info dir)))
3960 (if fsinfo
3961 (format "%.0f" (/ (nth 2 fsinfo) 1024))))
3962 (save-match-data
3963 (with-temp-buffer
3964 (when (and directory-free-space-program
3965 (zerop (call-process directory-free-space-program
3966 nil t nil
3967 directory-free-space-args
3968 dir)))
3969 ;; Usual format is a header line followed by a line of
3970 ;; numbers.
3971 (goto-char (point-min))
3972 (forward-line 1)
3973 (if (not (eobp))
3974 (progn
3975 ;; Move to the end of the "available blocks" number.
3976 (skip-chars-forward "^ \t")
3977 (forward-word 3)
3978 ;; Copy it into AVAILABLE.
3979 (let ((end (point)))
3980 (forward-word -1)
3981 (buffer-substring (point) end)))))))))
3982
3983
3984 ;; insert-directory
3985 ;; - must insert _exactly_one_line_ describing FILE if WILDCARD and
3986 ;; FULL-DIRECTORY-P is nil.
3987 ;; The single line of output must display FILE's name as it was
3988 ;; given, namely, an absolute path name.
3989 ;; - must insert exactly one line for each file if WILDCARD or
3990 ;; FULL-DIRECTORY-P is t, plus one optional "total" line
3991 ;; before the file lines, plus optional text after the file lines.
3992 ;; Lines are delimited by "\n", so filenames containing "\n" are not
3993 ;; allowed.
3994 ;; File lines should display the basename.
3995 ;; - must be consistent with
3996 ;; - functions dired-move-to-filename, (these two define what a file line is)
3997 ;; dired-move-to-end-of-filename,
3998 ;; dired-between-files, (shortcut for (not (dired-move-to-filename)))
3999 ;; dired-insert-headerline
4000 ;; dired-after-subdir-garbage (defines what a "total" line is)
4001 ;; - variable dired-subdir-regexp
4002 ;; - may be passed "--dired" as the first argument in SWITCHES.
4003 ;; Filename handlers might have to remove this switch if their
4004 ;; "ls" command does not support it.
4005 (defun insert-directory (file switches &optional wildcard full-directory-p)
4006 "Insert directory listing for FILE, formatted according to SWITCHES.
4007 Leaves point after the inserted text.
4008 SWITCHES may be a string of options, or a list of strings.
4009 Optional third arg WILDCARD means treat FILE as shell wildcard.
4010 Optional fourth arg FULL-DIRECTORY-P means file is a directory and
4011 switches do not contain `d', so that a full listing is expected.
4012
4013 This works by running a directory listing program
4014 whose name is in the variable `insert-directory-program'.
4015 If WILDCARD, it also runs the shell specified by `shell-file-name'."
4016 ;; We need the directory in order to find the right handler.
4017 (let ((handler (find-file-name-handler (expand-file-name file)
4018 'insert-directory)))
4019 (if handler
4020 (funcall handler 'insert-directory file switches
4021 wildcard full-directory-p)
4022 (if (eq system-type 'vax-vms)
4023 (vms-read-directory file switches (current-buffer))
4024 (let (result available (beg (point)))
4025
4026 ;; Read the actual directory using `insert-directory-program'.
4027 ;; RESULT gets the status code.
4028 (let* (;; We at first read by no-conversion, then after
4029 ;; putting text property `dired-filename, decode one
4030 ;; bunch by one to preserve that property.
4031 (coding-system-for-read 'no-conversion)
4032 ;; This is to control encoding the arguments in call-process.
4033 (coding-system-for-write
4034 (and enable-multibyte-characters
4035 (or file-name-coding-system
4036 default-file-name-coding-system))))
4037 (setq result
4038 (if wildcard
4039 ;; Run ls in the directory part of the file pattern
4040 ;; using the last component as argument.
4041 (let ((default-directory
4042 (if (file-name-absolute-p file)
4043 (file-name-directory file)
4044 (file-name-directory (expand-file-name file))))
4045 (pattern (file-name-nondirectory file)))
4046 (call-process
4047 shell-file-name nil t nil
4048 "-c"
4049 (concat (if (memq system-type '(ms-dos windows-nt))
4050 ""
4051 "\\") ; Disregard Unix shell aliases!
4052 insert-directory-program
4053 " -d "
4054 (if (stringp switches)
4055 switches
4056 (mapconcat 'identity switches " "))
4057 " -- "
4058 ;; Quote some characters that have
4059 ;; special meanings in shells; but
4060 ;; don't quote the wildcards--we want
4061 ;; them to be special. We also
4062 ;; currently don't quote the quoting
4063 ;; characters in case people want to
4064 ;; use them explicitly to quote
4065 ;; wildcard characters.
4066 (shell-quote-wildcard-pattern pattern))))
4067 ;; SunOS 4.1.3, SVr4 and others need the "." to list the
4068 ;; directory if FILE is a symbolic link.
4069 (apply 'call-process
4070 insert-directory-program nil t nil
4071 (append
4072 (if (listp switches) switches
4073 (unless (equal switches "")
4074 ;; Split the switches at any spaces so we can
4075 ;; pass separate options as separate args.
4076 (split-string switches)))
4077 ;; Avoid lossage if FILE starts with `-'.
4078 '("--")
4079 (progn
4080 (if (string-match "\\`~" file)
4081 (setq file (expand-file-name file)))
4082 (list
4083 (if full-directory-p
4084 (concat (file-name-as-directory file) ".")
4085 file))))))))
4086
4087 ;; If `insert-directory-program' failed, signal an error.
4088 (if (/= result 0)
4089 ;; On non-Posix systems, we cannot open a directory, so
4090 ;; don't even try, because that will always result in
4091 ;; the ubiquitous "Access denied". Instead, show the
4092 ;; command line so the user can try to guess what went wrong.
4093 (if (and (file-directory-p file)
4094 (memq system-type '(ms-dos windows-nt)))
4095 (error
4096 "Reading directory: \"%s %s -- %s\" exited with status %s"
4097 insert-directory-program
4098 (if (listp switches) (concat switches) switches)
4099 file result)
4100 ;; Unix. Access the file to get a suitable error.
4101 (access-file file "Reading directory")
4102 (error "Listing directory failed but `access-file' worked")))
4103
4104 (when (string-match "--dired\\>" switches)
4105 (forward-line -2)
4106 (when (looking-at "//SUBDIRED//")
4107 (delete-region (point) (progn (forward-line 1) (point)))
4108 (forward-line -1))
4109 (let ((end (line-end-position)))
4110 (forward-word 1)
4111 (forward-char 3)
4112 (while (< (point) end)
4113 (let ((start (+ beg (read (current-buffer))))
4114 (end (+ beg (read (current-buffer)))))
4115 (put-text-property start end 'dired-filename t)))
4116 (goto-char end)
4117 (beginning-of-line)
4118 (delete-region (point) (progn (forward-line 2) (point)))))
4119
4120 ;; Now decode what read if necessary.
4121 (let ((coding (or coding-system-for-write
4122 (detect-coding-region beg (point) t)))
4123 val pos)
4124 (if (not (eq (coding-system-base coding) 'undecided))
4125 (save-restriction
4126 (narrow-to-region beg (point))
4127 (goto-char (point-min))
4128 (while (not (eobp))
4129 (setq pos (point)
4130 val (get-text-property (point) 'dired-filename))
4131 (goto-char (next-single-property-change
4132 (point) 'dired-filename nil (point-max)))
4133 (decode-coding-region pos (point) coding)
4134 (if val
4135 (put-text-property pos (point) 'dired-filename t))))))
4136
4137 (if full-directory-p
4138 ;; Try to insert the amount of free space.
4139 (save-excursion
4140 (goto-char beg)
4141 ;; First find the line to put it on.
4142 (when (re-search-forward "^ *\\(total\\)" nil t)
4143 (let ((available (get-free-disk-space ".")))
4144 (when available
4145 ;; Replace "total" with "used", to avoid confusion.
4146 (replace-match "total used in directory" nil nil nil 1)
4147 (end-of-line)
4148 (insert " available " available)))))))))))
4149
4150 (defun insert-directory-safely (file switches
4151 &optional wildcard full-directory-p)
4152 "Insert directory listing for FILE, formatted according to SWITCHES.
4153
4154 Like `insert-directory', but if FILE does not exist, it inserts a
4155 message to that effect instead of signaling an error."
4156 (if (file-exists-p file)
4157 (insert-directory file switches wildcard full-directory-p)
4158 ;; Simulate the message printed by `ls'.
4159 (insert (format "%s: No such file or directory\n" file))))
4160
4161 (defvar kill-emacs-query-functions nil
4162 "Functions to call with no arguments to query about killing Emacs.
4163 If any of these functions returns nil, killing Emacs is cancelled.
4164 `save-buffers-kill-emacs' (\\[save-buffers-kill-emacs]) calls these functions,
4165 but `kill-emacs', the low level primitive, does not.
4166 See also `kill-emacs-hook'.")
4167
4168 (defcustom confirm-kill-emacs nil
4169 "How to ask for confirmation when leaving Emacs.
4170 If nil, the default, don't ask at all. If the value is non-nil, it should
4171 be a predicate function such as `yes-or-no-p'."
4172 :type '(choice (const :tag "Ask with yes-or-no-p" yes-or-no-p)
4173 (const :tag "Ask with y-or-n-p" y-or-n-p)
4174 (const :tag "Don't confirm" nil))
4175 :group 'emacs
4176 :version "21.1")
4177
4178 (defun save-buffers-kill-emacs (&optional arg)
4179 "Offer to save each buffer, then kill this Emacs process.
4180 With prefix arg, silently save all file-visiting buffers, then kill."
4181 (interactive "P")
4182 (save-some-buffers arg t)
4183 (and (or (not (memq t (mapcar (function
4184 (lambda (buf) (and (buffer-file-name buf)
4185 (buffer-modified-p buf))))
4186 (buffer-list))))
4187 (yes-or-no-p "Modified buffers exist; exit anyway? "))
4188 (or (not (fboundp 'process-list))
4189 ;; process-list is not defined on VMS.
4190 (let ((processes (process-list))
4191 active)
4192 (while processes
4193 (and (memq (process-status (car processes)) '(run stop open listen))
4194 (process-query-on-exit-flag (car processes))
4195 (setq active t))
4196 (setq processes (cdr processes)))
4197 (or (not active)
4198 (list-processes t)
4199 (yes-or-no-p "Active processes exist; kill them and exit anyway? "))))
4200 ;; Query the user for other things, perhaps.
4201 (run-hook-with-args-until-failure 'kill-emacs-query-functions)
4202 (or (null confirm-kill-emacs)
4203 (funcall confirm-kill-emacs "Really exit Emacs? "))
4204 (kill-emacs)))
4205 \f
4206 ;; We use /: as a prefix to "quote" a file name
4207 ;; so that magic file name handlers will not apply to it.
4208
4209 (setq file-name-handler-alist
4210 (cons '("\\`/:" . file-name-non-special)
4211 file-name-handler-alist))
4212
4213 ;; We depend on being the last handler on the list,
4214 ;; so that anything else which does need handling
4215 ;; has been handled already.
4216 ;; So it is safe for us to inhibit *all* magic file name handlers.
4217
4218 (defun file-name-non-special (operation &rest arguments)
4219 (let ((file-name-handler-alist nil)
4220 (default-directory
4221 (if (eq operation 'insert-directory)
4222 (directory-file-name
4223 (expand-file-name
4224 (unhandled-file-name-directory default-directory)))
4225 default-directory))
4226 ;; Get a list of the indices of the args which are file names.
4227 (file-arg-indices
4228 (cdr (or (assq operation
4229 ;; The first five are special because they
4230 ;; return a file name. We want to include the /:
4231 ;; in the return value.
4232 ;; So just avoid stripping it in the first place.
4233 '((expand-file-name . nil)
4234 (file-name-directory . nil)
4235 (file-name-as-directory . nil)
4236 (directory-file-name . nil)
4237 (file-name-sans-versions . nil)
4238 ;; `identity' means just return the first arg
4239 ;; as stripped of its quoting.
4240 (substitute-in-file-name . identity)
4241 (file-name-completion 1)
4242 (file-name-all-completions 1)
4243 (rename-file 0 1)
4244 (copy-file 0 1)
4245 (make-symbolic-link 0 1)
4246 (add-name-to-file 0 1)))
4247 ;; For all other operations, treat the first argument only
4248 ;; as the file name.
4249 '(nil 0))))
4250 ;; Copy ARGUMENTS so we can replace elements in it.
4251 (arguments (copy-sequence arguments)))
4252 ;; Strip off the /: from the file names that have this handler.
4253 (save-match-data
4254 (while (consp file-arg-indices)
4255 (let ((pair (nthcdr (car file-arg-indices) arguments)))
4256 (and (car pair)
4257 (string-match "\\`/:" (car pair))
4258 (setcar pair
4259 (if (= (length (car pair)) 2)
4260 "/"
4261 (substring (car pair) 2)))))
4262 (setq file-arg-indices (cdr file-arg-indices))))
4263 (if (eq file-arg-indices 'identity)
4264 (car arguments)
4265 (apply operation arguments))))
4266 \f
4267 (define-key ctl-x-map "\C-f" 'find-file)
4268 (define-key ctl-x-map "\C-r" 'find-file-read-only)
4269 (define-key ctl-x-map "\C-v" 'find-alternate-file)
4270 (define-key ctl-x-map "\C-s" 'save-buffer)
4271 (define-key ctl-x-map "s" 'save-some-buffers)
4272 (define-key ctl-x-map "\C-w" 'write-file)
4273 (define-key ctl-x-map "i" 'insert-file)
4274 (define-key esc-map "~" 'not-modified)
4275 (define-key ctl-x-map "\C-d" 'list-directory)
4276 (define-key ctl-x-map "\C-c" 'save-buffers-kill-emacs)
4277 (define-key ctl-x-map "\C-q" 'toggle-read-only)
4278
4279 (define-key ctl-x-4-map "f" 'find-file-other-window)
4280 (define-key ctl-x-4-map "r" 'find-file-read-only-other-window)
4281 (define-key ctl-x-4-map "\C-f" 'find-file-other-window)
4282 (define-key ctl-x-4-map "b" 'switch-to-buffer-other-window)
4283 (define-key ctl-x-4-map "\C-o" 'display-buffer)
4284
4285 (define-key ctl-x-5-map "b" 'switch-to-buffer-other-frame)
4286 (define-key ctl-x-5-map "f" 'find-file-other-frame)
4287 (define-key ctl-x-5-map "\C-f" 'find-file-other-frame)
4288 (define-key ctl-x-5-map "r" 'find-file-read-only-other-frame)
4289
4290 ;;; files.el ends here