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1 ;;; files.el --- file input and output commands for Emacs
3 ;; Copyright (C) 1985, 86, 87, 92, 93,
4 ;; 94, 95, 1996 Free Software Foundation, Inc.
6 ;; Maintainer: FSF
8 ;; This file is part of GNU Emacs.
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.
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.
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.
25 ;;; Commentary:
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.
31 ;;; Code:
37 nil
38 "*Alist of abbreviations for file directories.
39 A list of elements of the form (FROM . TO), each meaning to replace
40 FROM with TO when it appears in a directory name. This replacement is
41 done when setting up the default directory of a newly visited file.
42 *Every* FROM string should start with `^'.
44 Do not use `~' in the TO strings.
45 They should be ordinary absolute directory names.
47 Use this feature when you have directories which you normally refer to
48 via absolute symbolic links. Make TO the name of the link, and FROM
51 ;;; Turn off backup files on VMS since it has version numbers.
53 "*Non-nil means make a backup of a file the first time it is saved.
54 This can be done by renaming the file or by copying.
56 Renaming means that Emacs renames the existing file so that it is a
57 backup file, then writes the buffer into a new file. Any other names
58 that the old file had will now refer to the backup file. The new file
59 is owned by you and its group is defaulted.
61 Copying means that Emacs copies the existing file into the backup
62 file, then writes the buffer on top of the existing file. Any other
63 names that the old file had will now refer to the new (edited) file.
64 The file's owner and group are unchanged.
66 The choice of renaming or copying is controlled by the variables
67 `backup-by-copying', `backup-by-copying-when-linked' and
70 ;; Do this so that local variables based on the file name
71 ;; are not overridden by the major mode.
73 "Non-nil means don't make a backup, regardless of the other parameters.
74 This variable is intended for use by making it local to a buffer.
79 "*Non-nil means always use copying to create backup files.
83 "*Non-nil means use copying to create backups for files with multiple names.
84 This causes the alternate names to refer to the latest version as edited.
88 "*Non-nil means create backups by copying if this preserves owner or group.
89 Renaming may still be used (subject to control of other variables)
90 when it would not result in changing the owner or group of the file;
91 that is, for files which are owned by you and whose group matches
92 the default for a new file created there by you.
99 "Predicate that looks at a file name and decides whether to make backups.
103 "*Non-nil in a buffer means offer to save the buffer on exit
104 even if the buffer is not visiting a file.
109 "*Non-nil means find a file under alternative names, in existing buffers.
110 This means if any existing buffer is visiting the file you want
114 "*Non-nil means visit a file under its truename.
115 The truename of a file is found by chasing all links
119 "The device number and file number of the file visited in the current buffer.
120 The value is a list of the form (FILENUM DEVNUM).
121 This pair of numbers uniquely identifies the file.
130 "*Non-nil means protect against I/O errors while saving files.
131 Some modes set this non-nil in particular buffers.
133 This feature works by writing the new contents into a temporary file
134 and then renaming the temporary file to replace the original.
135 In this way, any I/O error in writing leaves the original untouched,
136 and there is never any instant where the file is nonexistent.
138 Note that this feature forces backups to be made by copying.
139 Yet, at the same time, saving a precious file
143 "*Control use of version numbers for backup files.
144 t means make numeric backup versions unconditionally.
145 nil means make them for files that have some already.
152 "*If t, delete excess backup versions silently.
159 "*Number of newest versions to keep when a new numbered backup is made.
163 "*Value of t says silently ensure a file ends in a newline when it is saved.
164 Non-nil but not t says ask user whether to add a newline when there isn't one.
171 "*Non-nil says auto-save a buffer in the file it is visiting, when practical.
175 "*Non-nil means save word abbrevs too when files are saved.
181 ;;;It is not useful to make this a local variable.
182 ;;;(put 'find-file-not-found-hooks 'permanent-local t)
184 "List of functions to be called for `find-file' on nonexistent file.
185 These functions are called as soon as the error is detected.
186 `buffer-file-name' is already set up.
189 ;;;It is not useful to make this a local variable.
190 ;;;(put 'find-file-hooks 'permanent-local t)
192 "List of functions to be called after a buffer is loaded from a file.
193 The buffer's local variables (if any) will have been processed before the
197 "List of functions to be called before writing out a buffer to a file.
198 If one of them returns non-nil, the file is considered already written
199 and the rest are not called.
200 These hooks are considered to pertain to the visited file.
201 So this list is cleared if you change the visited file name.
203 Don't make this variable buffer-local; instead, use `local-write-file-hooks'.
205 ;;; However, in case someone does make it local...
209 "Just like `write-file-hooks', except intended for per-buffer use.
210 The functions in this list are called before the ones in
211 `write-file-hooks'.
213 This variable is meant to be used for hooks that have to do with a
214 particular visited file. Therefore, it is a permanent local, so that
215 changing the major mode does not clear it. However, calling
221 "List of functions to be called before writing out a buffer to a file.
222 If one of them returns non-nil, the file is considered already written
223 and the rest are not called.
225 This variable is meant to be used for hooks that pertain to the
226 buffer's contents, not to the particular visited file; thus,
227 `set-visited-file-name' does not clear this variable; but changing the
228 major mode does clear it.
230 This variable automatically becomes buffer-local whenever it is set.
231 If you use `add-hooks' to add elements to the list, use nil for the
232 LOCAL argument.
238 "*Control use of local-variables lists in files you visit.
239 The value can be t, nil or something else.
240 A value of t means local-variables lists are obeyed;
241 nil means they are ignored; anything else means query.
248 The value can be t, nil or something else.
249 A value of t means obey `eval' variables;
250 nil means ignore them; anything else means query.
255 ;; Avoid losing in versions where CLASH_DETECTION is disabled.
261 ;; This hook function provides support for ange-ftp host name
262 ;; completion. It runs the usual ange-ftp hook, but only for
263 ;; completion operations. Having this here avoids the need
264 ;; to load ange-ftp when it's not really in use.
271 inhibit-file-name-handlers)))
276 "Convert a standard file's name to something suitable for the current OS.
277 This function's standard definition is trivial; it just returns the argument.
278 However, on some systems, the function is redefined
279 with a definition that really does change some file names."
280 filename)
281 \f
283 "Show the current default directory."
288 "Value of the CDPATH environment variable, as a list.
295 "Explode a colon-separated list of paths into a string list."
303 nil
308 cd-list)))
311 "Change current directory to given absolute file name DIR."
312 ;; Put the name into directory syntax now,
313 ;; because otherwise expand-file-name may give some bad results.
324 "Make DIR become the current buffer's default directory.
325 If your environment includes a `CDPATH' variable, try each one of that
326 colon-separated list of directories when resolving a relative directory name."
329 default-directory default-directory
345 cd-path)
346 nil))
350 "Load the Lisp file named FILE."
355 "Load the library named LIBRARY.
356 This is an interface to the function `load'."
361 "Copy the file FILE into a temporary file on this machine.
362 Returns the name of the local copy, or nil, if FILE is directly
363 accessible."
367 nil)))
370 "Return the truename of FILENAME, which should be absolute.
371 The truename of a file name is found by chasing symbolic links
372 both at the level of the file and at the level of the directories
373 containing it, until no links are left at any level.
375 The arguments COUNTER and PREV-DIRS are used only in recursive calls.
376 Do not specify them in other calls."
377 ;; COUNTER can be a cons cell whose car is the count of how many more links
378 ;; to chase before getting an error.
379 ;; PREV-DIRS can be a cons cell whose car is an alist
380 ;; of truenames we've just recently computed.
382 ;; The last test looks dubious, maybe `+' is meant here? --simon.
392 ;; For speed, remove the ange-ftp completion handler from the list.
393 ;; We know it's not needed here.
394 ;; For even more speed, do this only on the outermost call.
400 ;; If this file directly leads to a link, process that iteratively
401 ;; so that we don't use lots of stack.
407 ;; For file name that has a special handler, call handler.
408 ;; This is so that ange-ftp can save time by doing a no-op.
411 done t)
413 target dirfile)
414 ;; Get the truename of the directory.
416 ;; If these are equal, we have the (or a) root directory.
418 ;; If this is the same dir we last got the truename for,
419 ;; save time--don't recalculate.
429 done t)
432 done t)
433 ;; Put it back on the file name.
435 ;; Is the file name the name of a link?
438 ;; Yes => chase that link, then start all over
439 ;; since the link may point to a directory name that uses links.
440 ;; We can't safely use expand-file-name here
441 ;; since target might look like foo/../bar where foo
442 ;; is itself a link. Instead, we handle . and .. above.
445 target
447 done nil)
448 ;; No, we are done!
450 filename))
453 "Chase links in FILENAME until a name that is not a link.
454 Does not examine containing directories for links,
455 unlike `file-truename'."
460 ;; In the context of a link, `//' doesn't mean what Emacs thinks.
464 ;; Handle `..' by hand, since it needs to work in the
465 ;; target of any directory symlink.
466 ;; This code is not quite complete; it does not handle
467 ;; embedded .. in some cases such as ./../foo and foo/bar/../../../lose.
471 ;; Do the .. by hand.
474 ;; Chase links in the default dir of the symlink.
480 newname))
481 \f
483 "Select buffer BUFFER in another window."
489 "Switch to buffer BUFFER in another frame."
496 "Edit file FILENAME.
497 Switch to a buffer visiting file FILENAME,
498 creating one if none already exists."
503 "Edit file FILENAME, in another window.
504 May create a new window, or reuse an existing one.
505 See the function `display-buffer'."
510 "Edit file FILENAME, in another frame.
511 May create a new frame, or reuse an existing one.
512 See the function `display-buffer'."
517 "Edit file FILENAME but don't allow changes.
526 "Edit file FILENAME in another window but don't allow changes.
535 "Edit file FILENAME in another frame but don't allow changes.
544 "Find file FILENAME as a replacement for the file in the next window.
545 This command does not select that window."
564 "Find file FILENAME, select its buffer, kill previous buffer.
565 If the current buffer now contains an empty file that you just visited
566 \(presumably by mistake), use this command to visit the file you really want."
577 ;; (not buffer-read-only)
606 "Create a suitably named buffer for visiting FILENAME, and return it.
607 FILENAME (sans directory) is used unchanged if that name is free;
608 otherwise a string <2> or <3> or ... is appended to get an unused name."
615 "Create and return a buffer with a name based on NAME.
616 Choose the buffer's name using `generate-new-buffer-name'."
626 "Return a version of FILENAME shortened using `directory-abbrev-alist'.
629 ;; Get rid of the prefixes added by the automounter.
636 ;; If any elt of directory-abbrev-alist matches this name,
637 ;; abbreviate accordingly.
643 ;; Compute and save the abbreviated homedir name.
644 ;; We defer computing this until the first time it's needed, to
645 ;; give time for directory-abbrev-alist to be set properly.
646 ;; We include a slash at the end, to avoid spurious matches
647 ;; such as `/usr/foobar' when the home dir is `/usr/foo'.
654 ;; If FILENAME starts with the abbreviated homedir,
655 ;; make it start with `~' instead.
657 ;; If the home dir is just /, don't change it.
660 ;; MS-DOS root directories can come with a drive letter;
661 ;; Novell Netware allows drive letters beyond `Z:'.
670 filename))
673 "*List of logical names for which visiting shouldn't save the true dirname.
674 On VMS, when you visit a file using a logical name that searches a path,
675 you may or may not want the visited file name to record the specific
676 directory where the file was found. If you *do not* want that, add the logical
680 "Return the buffer visiting file FILENAME (a string).
681 This is like `get-file-buffer', except that it checks for any buffer
682 visiting the same file, possibly under a different name.
683 If there is no such live buffer, return nil."
695 found)
699 number
705 ;; Verify this buffer's file number
706 ;; still belongs to its file.
709 number))
712 found))))
715 "Like `insert-file-contents', q.v., but only reads in the file.
716 A buffer may be modified in several ways after reading into the buffer due
717 to advanced Emacs features, such as file-name-handlers, format decoding,
718 find-file-hooks, etc.
719 This function ensures that none of these modifications will take place."
726 nil)))
736 "Read file FILENAME into a buffer and return the buffer.
737 If a buffer exists visiting FILENAME, return that one, but
738 verify that the file has not changed since visited or saved.
739 The buffer is not selected, just returned to the caller."
747 filename))
752 ;; Find any buffer for a file which has same truename.
754 error)
755 ;; Let user know if there is a buffer with the same truename.
762 ;; Optionally also find that buffer.
775 "File %s changed on disk. Discard your edits? "
780 "File %s changed on disk. Discard your edits in %s? "
788 ;;; The truename stuff makes this obsolete.
789 ;;; (let* ((link-name (car (file-attributes filename)))
790 ;;; (linked-buf (and (stringp link-name)
791 ;;; (get-file-buffer link-name))))
792 ;;; (if (bufferp linked-buf)
793 ;;; (message "Symbolic link to file in buffer %s"
794 ;;; (buffer-name linked-buf))))
803 ;; Unconditionally set error
808 ;; Run find-file-not-found-hooks until one returns non-nil.
810 ;; If they fail too, set error.
812 ;; Find the file's truename, and maybe use that as visited name.
815 ;; On VMS, we may want to remember which directory in a search list
816 ;; the file was found in.
828 ;; Set buffer's default directory to that of the file.
830 ;; Turn off backup files for certain file names. Since
831 ;; this is a permanent local, the major mode won't eliminate it.
837 nil
840 buf)))
841 \f
845 after-find-file-from-revert-buffer
846 nomodes)
847 "Called after finding a file and by the default revert function.
848 Sets buffer mode, parses local variables.
849 Optional args ERROR, WARN, and NOAUTO: ERROR non-nil means there was an
850 error in reading the file. WARN non-nil means warn if there
851 exists an auto-save file more recent than the visited file.
852 NOAUTO means don't mess with auto-save mode.
853 Fourth arg AFTER-FIND-FILE-FROM-REVERT-BUFFER non-nil
854 means this call was from `revert-buffer'.
855 Fifth arg NOMODES non-nil means don't alter the file's modes.
856 Finishes by calling the functions in `find-file-hooks'
857 unless NOMODES is non-nil."
860 nil
869 buffer-file-name))
883 (if (file-exists-p (file-name-directory (directory-file-name (file-name-directory buffer-file-name))))
884 "Use M-x make-dir RET RET to create the directory"
893 nil
898 "Choose the major mode for this buffer automatically.
899 Also sets up any specified local variables of the file.
900 Uses the visited file name, the -*- line, and the local variables spec.
902 This function is called automatically from `find-file'. In that case,
903 we may set up specified local variables depending on the value of
904 `enable-local-variables': if it is t, we do; if it is nil, we don't;
905 otherwise, we query. `enable-local-variables' is ignored if you
906 run `normal-mode' explicitly."
915 enable-local-variables)))
956 ;;; Less common extensions come here
957 ;;; so more common ones above are found faster.
973 ;;; The following should come after the ChangeLog pattern
974 ;;; for the sake of ChangeLog.1, etc.
975 ;;; and after the .scm.[0-9] pattern too.
995 ;; Mailer puts message to be edited in
996 ;; /tmp/Re.... or Message
1000 ;; some news reader is reported to use this
1008 ;; .emacs following a directory delimiter
1009 ;; in either Unix or VMS syntax.
1011 ;; _emacs following a directory delimiter
1012 ;; in MsDos syntax
1015 "\
1016 Alist of filename patterns vs corresponding major mode functions.
1017 Each element looks like (REGEXP . FUNCTION) or (REGEXP FUNCTION NON-NIL).
1018 \(NON-NIL stands for anything that is not nil; the value does not matter.)
1019 Visiting a file whose name matches REGEXP specifies FUNCTION as the
1020 mode function to use. FUNCTION will be called, unless it is nil.
1022 If the element has the form (REGEXP FUNCTION NON-NIL), then after
1023 calling FUNCTION (if it's not nil), we delete the suffix that matched
1059 "Alist mapping interpreter names to major modes.
1060 This alist applies to files whose first line starts with `#!'.
1061 Each element looks like (INTERPRETER . MODE).
1062 The car of each element is compared with
1063 the name of the interpreter specified in the first line.
1070 "List of regexps for what to ignore, for `inhibit-first-line-modes-regexps'.
1071 When checking `inhibit-first-line-modes-regexps', we first discard
1079 "Select major mode appropriate for current buffer.
1080 This checks for a -*- mode tag in the buffer's text,
1081 compares the filename against the entries in `auto-mode-alist',
1082 or checks the interpreter that runs this file against
1083 `interpreter-mode-alist'.
1085 It does not check for the `mode:' local variable in the
1086 Local Variables section of the file; for that, use `hack-local-variables'.
1088 If `enable-local-variables' is nil, this function does not check for a
1089 -*- mode tag."
1090 ;; Look for -*-MODENAME-*- or -*- ... mode: MODENAME; ... -*-
1096 ;; Don't look for -*- if this file name matches any
1097 ;; of the regexps in inhibit-first-line-modes-regexps.
1105 sufs)
1112 ;; If the file begins with "#!"
1113 ;; (exec interpreter magic), look
1114 ;; for mode frobs in the first two
1115 ;; lines. You cannot necessarily
1116 ;; put them in the first line of
1117 ;; such a file without screwing up
1118 ;; the interpreter invocation.
1126 t))
1133 ;; Find all specifications for the `mode:' variable
1134 ;; and execute them left to right.
1146 modes)))
1147 ;; Simple -*-MODE-*- case.
1150 modes))))))
1151 ;; If we found modes to use, invoke them now,
1152 ;; outside the save-excursion.
1156 ;; If we didn't find a mode from a -*- line, try using the file name.
1160 ;; Remove backup-suffixes from file name.
1166 ;; Find first matching alist entry.
1176 keep-going t))
1178 keep-going nil)))
1182 ;; If we can't deduce a mode from the file name,
1183 ;; look for an interpreter specified in the first line.
1184 ;; As a special case, allow for things like "#!/bin/env perl",
1185 ;; which finds the interpreter anywhere in $PATH.
1193 elt)
1194 ;; Map interpreter name to a mode.
1196 interpreter-mode-alist))
1201 ;; Set local variables specified in the -*- line.
1202 ;; Ignore any specification for `mode:';
1203 ;; set-auto-mode should already have handled that.
1208 ;; Parse the -*- line into the `result' alist.
1210 ;; doesn't have one.
1211 nil)
1213 ;; Simple form: "-*- MODENAME -*-". Already handled.
1214 nil)
1216 ;; Hairy form: '-*-' [ <variable> ':' <value> ';' ]* '-*-'
1217 ;; (last ";" is optional).
1226 ;; There used to be a downcase here,
1227 ;; but the manual didn't say so,
1228 ;; and people want to set var names that aren't all lc.
1247 ;; If we fail to switch in the selected window,
1248 ;; it is probably a minibuffer.
1249 ;; So try another window.
1262 "Normal hook run after processing a file's local variables specs.
1263 Major modes can use this to examine user-specified local variables
1267 "Parse and put into effect this buffer's local variables spec."
1269 ;; Look for "Local variables:" line in last page.
1285 buffer-file-name)
1289 prefix prefixlen suffix beg
1291 ;; The prefix is what comes before "local variables:" in its line.
1292 ;; The suffix is what comes after "local variables:" in its line.
1307 ;; Look at next local variable spec.
1310 ;; Skip the prefix, if any.
1315 ;; Find the variable name; strip whitespace.
1323 val)
1324 ;; Setting variable named "end" means end of list.
1327 ;; Otherwise read the variable value.
1335 ;; Set the variable. "Variables" mode and eval are funny.
1343 ;; Get confirmation before setting these variables as locals in a file.
1360 ;; Don't wait for outline.el to be loaded, for the sake of outline-minor-mode.
1364 ;; This one is safe because the user gets to check it before it is used.
1370 ;; "Set" one variable in a local variables spec.
1371 ;; A few variable names are treated specially.
1377 nil)
1378 ;; "Setting" eval means either eval it or do nothing.
1379 ;; Likewise for setting hook variables.
1385 ;; Permit evalling a put of a harmless property.
1386 ;; if the args do nothing tricky.
1392 ;; Only allow safe values of lisp-indent-hook;
1393 ;; not functions.
1398 ;; Permit eval if not root and user says ok.
1415 ;; Ordinary variable, really set it.
1419 \f
1421 "Change name of file visited in current buffer to FILENAME.
1422 The next time the buffer is saved it will go in the newly specified file.
1423 nil or empty string as argument means make buffer not be visiting any file.
1424 Remember to delete the initial contents of the minibuffer
1425 if you wish to pass an empty string as the argument.
1427 The optional second argument NO-QUERY, if non-nil, inhibits asking for
1428 confirmation in the case where the file FILENAME already exists."
1436 nil
1447 filename)))
1465 ;; Abbreviate the file names of the buffer.
1474 nil)))
1475 ;; write-file-hooks is normally used for things like ftp-find-file
1476 ;; that visit things that are not local files as if they were files.
1477 ;; Changing to visit an ordinary local file instead should flush the hook.
1482 ;; If buffer was read-only because of version control,
1483 ;; that reason is gone now, so make it writable.
1487 ;; Turn off backup files for certain file names.
1488 ;; Since this is a permanent local, the major mode won't eliminate it.
1494 ;; If auto-save was not already on, turn it on if appropriate.
1498 ;; If auto save is on, start using a new name.
1499 ;; We deliberately don't rename or delete the old auto save
1500 ;; for the old visited file name. This is because perhaps
1501 ;; the user wants to save the new state and then compare with the
1502 ;; previous state from the auto save file.
1505 ;; Rename the old auto save file if any.
1513 "Write current buffer into file FILENAME.
1514 Makes buffer visit that file, and marks it not modified.
1515 If the buffer is already visiting a file, you can specify
1516 a directory name as FILENAME, to write a file of the same
1517 old name in that directory.
1519 If optional second arg CONFIRM is non-nil,
1520 ask for confirmation for overwriting an existing file.
1521 Interactively, confirmation is required unless you supply a prefix argument."
1522 ;; (interactive "FWrite file: ")
1526 nil nil nil nil)
1534 ;; If arg is just a directory,
1535 ;; use same file name, but in that directory.
1546 \f
1548 "Make a backup of the disk file visited by the current buffer, if appropriate.
1549 This is normally done before saving the buffer the first time.
1550 If the value is non-nil, it is the result of `file-modes' on the original
1551 file; this means that the caller, after saving the buffer, should change
1552 the modes of the new file to agree with the old modes."
1559 backup-info backupname targets setmodes)
1560 ;; If specified name is a symbolic link, chase it to the target.
1561 ;; Thus we make the backups in the directory where the real file is.
1566 ;;; (if (file-directory-p buffer-file-name)
1567 ;;; (error "Cannot save buffer in directory %s" buffer-file-name))
1571 ;; If have old versions to maybe delete,
1572 ;; ask the user to confirm now, before doing anything.
1573 ;; But don't actually delete til later.
1578 real-file-name))))))
1579 ;; Actually write the back up file.
1582 ; (file-symlink-p buffer-file-name)
1583 backup-by-copying
1593 ;; If copying fails because file BACKUPNAME
1594 ;; is not writable, delete that file and try again.
1599 ;; rename-file should delete old backup.
1603 ;; If trouble writing the backup, write it in ~.
1613 ;; If copying fails because file BACKUPNAME
1614 ;; is not writable, delete that file and try again.
1620 ;; Now delete the old versions, if desired.
1627 setmodes)
1631 "Return FILENAME sans backup versions or strings.
1632 This is a separate procedure so your site-init or startup file can
1633 redefine it.
1634 If the optional argument KEEP-BACKUP-VERSION is non-nil,
1635 we do not remove backup version numbers, only true file version numbers."
1641 ;; VMS version number is (a) semicolon, optional
1642 ;; sign, zero or more digits or (b) period, option
1643 ;; sign, zero or more digits, provided this is the
1644 ;; second period encountered outside of the
1645 ;; device/directory part of the file name.
1648 name)
1658 "Returns t if deleting FILE and rewriting it would preserve the owner."
1663 ;; Return t if the file doesn't exist, since it's true that no
1664 ;; information would be lost by an (attempted) delete and create.
1670 The extension, in a file name, is the part that follows the last `.'."
1673 directory)
1677 directory)
1679 filename))))
1682 "Create the non-numeric backup file name for FILE.
1683 This is a separate function so you can redefine it for customization."
1696 "Return non-nil if FILE is a backup file name (numeric or not).
1697 This is a separate function so you can redefine it for customization.
1698 You may need to redefine `file-name-sans-versions' as well."
1701 ;; This is used in various files.
1702 ;; The usage of bv-length is not very clean,
1703 ;; but I can't see a good alternative,
1704 ;; so as of now I am leaving it alone.
1706 "Given the name of a numeric backup file, return the backup number.
1707 Uses the free variable `bv-length', whose value should be
1708 the index in the name where the version number begins."
1714 ;; I believe there is no need to alter this behavior for VMS;
1715 ;; since backup files are not made on VMS, it should not get called.
1717 "Find a file name for a backup file, and suggestions for deletions.
1718 Value is a list whose car is the name for the backup file
1719 and whose cdr is a list of old versions to consider deleting now.
1720 If the value is nil, don't make a backup."
1722 ;; Run a handler for this function so that ange-ftp can refuse to do it.
1729 possibilities
1736 base-versions
1740 possibilities)
1741 '<)
1753 ;; Delete nothing if there is overflow
1754 ;; in the number of versions to keep.
1760 v))))))))))
1763 "Return number of names file FILENAME has."
1767 "Convert FILENAME to be relative to DIRECTORY (default: default-directory)."
1776 \f
1778 "Save current buffer in visited file if modified. Versions described below.
1779 By default, makes the previous version into a backup file
1780 if previously requested or if this is the first save.
1782 to become a backup when the next save is done.
1784 unconditionally makes the previous version into a backup file.
1786 to become a backup when the next save is done,
1787 and unconditionally makes the previous version into a backup file.
1789 With argument of 0, never makes the previous version into a backup file.
1791 If a file's name is FOO, the names of its numbered backup versions are
1792 FOO.~i~ for various integers i. A non-numbered backup file is called FOO~.
1793 Numeric backups (rather than FOO~) will be made if value of
1794 `version-control' is not the atom `never' and either there are already
1795 numeric versions of the file being backed up, or `version-control' is
1796 non-nil.
1797 We don't want excessive versions piling up, so there are variables
1798 `kept-old-versions', which tells Emacs how many oldest versions to keep,
1799 and `kept-new-versions', which tells how many newest versions to keep.
1800 Defaults are 2 old versions and 2 new.
1801 `dired-kept-versions' controls dired's clean-directory (.) command.
1802 If `delete-old-versions' is nil, system will query user
1803 before trimming versions. Otherwise it does it silently."
1815 "Delete auto-save file for current buffer if `delete-auto-save-files' is t.
1816 Normally delete only if the file was written by this Emacs since
1817 the last real save, but optional arg FORCE non-nil means delete anyway."
1831 "Save the current buffer in its visited file, if it has been modified.
1832 After saving the buffer, run `after-save-hook'."
1835 ;; In an indirect buffer, save its base buffer instead.
1840 setmodes tempsetmodes)
1841 ;; On VMS, rename file and buffer to get rid of version number.
1846 ;; Strip VMS version number before save.
1849 ;; Construct a (unique) buffer name to correspond.
1854 ;; If buffer has no file name, ask user for one.
1861 filename))
1887 ;; If a hook returned t, file is already "written".
1888 ;; Otherwise, write it the usual way now.
1896 ;; If the auto-save file was recent before this command,
1897 ;; delete it now.
1899 ;; Support VC `implicit' locking.
1904 ;; This does the "real job" of writing a buffer into its visited file
1905 ;; and making a backup file. This is what is normally done
1906 ;; but inhibited if one of write-file-hooks returns non-nil.
1907 ;; It returns a value to store in setmodes.
1919 buffer-file-name)))
1927 ;; If file is precious, write temp name, then rename it.
1928 ;; This requires write access to the containing dir,
1929 ;; which is why we don't try it if we don't have that access.
1931 tempname temp nogood i succeed
1935 ;; Find the temporary name to write under.
1942 dir i))
1948 tempname nil realname
1949 buffer-file-truename)
1951 ;; If writing the temp file fails,
1952 ;; delete the temp file.
1957 ;; Since we have created an entirely new file
1958 ;; and renamed it, make sure it gets the
1959 ;; right permission bits set.
1961 ;; We succeeded in writing the temp file,
1962 ;; so rename it.
1964 ;; If file not writable, see if we can make it writable
1965 ;; temporarily while we write it.
1966 ;; But no need to do so if we have just backed it up
1967 ;; (setmodes is set) because that says we're superseding.
1969 ;; Change the mode back, after writing.
1973 buffer-file-name nil t buffer-file-truename)))
1974 setmodes))
1977 "Save some modified file-visiting buffers. Asks user about each one.
1978 Optional argument (the prefix) non-nil means save all with no questions.
1979 Optional second argument EXITING means ask about certain non-file buffers
1980 as well as about file buffers."
1997 t
2016 ;; Return nil to ask about BUF again.
2017 nil)
2024 abbrev-file-name)))
2026 ;; Don't keep bothering user if he says no.
2028 t))))
2031 \f
2033 "Mark current buffer as unmodified, not needing to be saved.
2036 It is not a good idea to use this function in Lisp programs, because it
2037 prints a message in the minibuffer. Instead, use `set-buffer-modified-p'."
2044 "Change whether this buffer is visiting its file read-only.
2045 With arg, set read-only iff arg is positive."
2054 "Insert contents of file FILENAME into buffer after point.
2055 Set mark after the inserted text.
2057 This function is meant for the user to run interactively.
2058 Don't call it from programs! Use `insert-file-contents' instead.
2059 \(Its calling sequence is different; see its documentation)."
2063 filename)))
2068 "Append the contents of the region to the end of file FILENAME.
2069 When called from a function, expects three arguments,
2070 START, END and FILENAME. START and END are buffer positions
2071 saying what text to write."
2076 "Return most recent backup file for FILENAME or nil if no backups exist."
2082 tem)
2092 newest))
2095 "Rename current buffer to a similar name not already taken.
2096 This function is useful for creating multiple shell process buffers
2097 or multiple mail buffers, etc."
2104 buffer-file-name)))))
2105 ;; If the existing buffer name has a <NNN>,
2106 ;; which isn't part of the file name (if any),
2107 ;; then get rid of that.
2117 "Create the directory DIR and any nonexistent parent dirs.
2118 Interactively, the default choice of directory to create
2119 is the current default directory for file names.
2120 That is useful when you have visited a file in a nonexistent directory.
2122 Noninteractively, the second (optional) argument PARENTS says whether
2123 to create parent directories if they don't exist."
2126 nil nil)
2127 t))
2134 create-list)
2141 \f
2144 "Function to use to revert this buffer, or nil to do the default.
2145 The function receives two arguments IGNORE-AUTO and NOCONFIRM,
2150 "Function to use to insert contents when reverting this buffer.
2151 Gets two args, first the nominal file name to use,
2155 "Normal hook for `revert-buffer' to run before reverting.
2156 If `revert-buffer-function' is used to override the normal revert
2160 "Normal hook for `revert-buffer' to run after reverting.
2161 Note that the hook value that it runs is the value that was in effect
2162 before reverting; that makes a difference if you have buffer-local
2163 hook functions.
2165 If `revert-buffer-function' is used to override the normal revert
2169 "Replace the buffer text with the text of the visited file on disk.
2170 This undoes all changes since the file was visited or saved.
2171 With a prefix argument, offer to revert from latest auto-save file, if
2172 that is more recent than the visited file.
2174 When called from Lisp, the first argument is IGNORE-AUTO; only offer
2175 to revert from the auto-save file when this is nil. Note that the
2176 sense of this argument is the reverse of the prefix argument, for the
2177 sake of backward compatibility. IGNORE-AUTO is optional, defaulting
2178 to nil.
2180 Optional second argument NOCONFIRM means don't ask for confirmation at
2181 all.
2183 Optional third argument PRESERVE-MODES non-nil means don't alter
2184 the files modes. Normally we reinitialize them using `normal-mode'.
2186 If the value of `revert-buffer-function' is non-nil, it is called to
2187 do the work.
2189 The default revert function runs the hook `before-revert-hook' at the
2190 beginning and `after-revert-hook' at the end."
2191 ;; I admit it's odd to reverse the sense of the prefix argument, but
2192 ;; there is a lot of code out there which assumes that the first
2193 ;; argument should be t to avoid consulting the auto-save file, and
2194 ;; there's no straightforward way to encourage authors to notice a
2195 ;; reversal of the argument sense. So I'm just changing the user
2196 ;; interface, but leaving the programmatic interface the same.
2203 buffer-auto-save-file-name
2208 buffer-auto-save-file-name
2209 buffer-file-name)))
2214 file-name)))
2216 ;; If file was backed up but has changed since,
2217 ;; we shd make another backup.
2221 ;; Get rid of all undo records for this buffer.
2224 ;; Effectively copy the after-revert-hook status,
2225 ;; since after-find-file will clobber it.
2229 after-revert-hook)))
2231 ;; Don't make undo records for the reversion.
2235 file-name auto-save-p)
2238 ;; Bind buffer-file-name to nil
2239 ;; so that we don't try to lock the file.
2245 nil nil t)))
2247 ;; Recompute the truename in case changes in symlinks
2248 ;; have changed the truename.
2252 ;; Run after-revert-hook as it was before we reverted.
2260 t)))))
2263 "Visit file FILE, but get contents from its last auto-save file."
2264 ;; Actually putting the file name in the minibuffer should be used
2265 ;; only rarely.
2266 ;; Not just because users often use the default.
2283 file file-name)))
2293 "Recover auto save files from a previous Emacs session.
2294 This command first displays a Dired buffer showing you the
2295 previous sessions that you could recover from.
2296 To choose one, move point to the proper line and then type C-c C-c.
2297 Then you'll be asked about a number of files to recover."
2312 "Choose one saved session to recover auto-save files from.
2313 This command is used in the special Dired buffer created by
2316 ;; Get the name of the session file to recover from.
2318 files
2323 ;; Read in the auto-save-list file.
2327 ;; Loop thru the text of that file
2328 ;; and get out the names of the files to recover.
2332 ;; This is a pair of lines for a non-file-visiting buffer.
2333 ;; Get the auto-save file name and manufacture
2334 ;; a "visited file name" from that.
2350 ;; This pair of lines is a file-visiting
2351 ;; buffer. Use the visited file name.
2361 ;; Ignore a file if its auto-save file does not exist now.
2365 ;; The file contains a pair of line for each auto-saved buffer.
2366 ;; The first line of the pair contains the visited file name
2367 ;; or is empty if the buffer was not visiting a file.
2368 ;; The second line is the auto-save file name.
2376 files
2382 "For each buffer in LIST, ask whether to kill it.
2383 LIST defaults to all existing live buffers."
2394 name
2399 \f
2401 "Toggle auto-saving of contents of current buffer.
2402 With prefix argument ARG, turn auto-saving on if positive, else off."
2407 ;; If autosave is off because buffer has shrunk,
2408 ;; then toggling should turn it on.
2413 buffer-file-name
2415 ;; If -1 was stored here, to temporarily turn off saving,
2416 ;; turn it back on.
2422 buffer-auto-save-file-name)
2425 "Adjust current buffer's auto save file name for current conditions.
2426 Also rename any existing auto save file, if it was made in this session."
2438 "Return file name to use for auto-saves of current buffer.
2439 Does not consider `auto-save-visited-file-name' as that variable is checked
2440 before calling this function. You can redefine this for customization.
2441 See also `auto-save-file-name-p'."
2451 "#"
2455 ;; Deal with buffers that don't have any associated files. (Mail
2456 ;; mode tends to create a good number of these.)
2460 ;; Use technique from Sebastian Kremer's auto-save
2461 ;; package to turn slashes into \\!. This ensures that
2462 ;; the auto-save buffer name is unique.
2474 ;; Generate the file name.
2477 ;; Try a few alternative directories, to get one we can write it.
2484 "Return non-nil if FILENAME can be yielded by `make-auto-save-file-name'.
2485 FILENAME should lack slashes. You can redefine this for customization."
2487 \f
2489 "Given a shell file name pattern WILDCARD, return an equivalent regexp.
2490 The generated regexp will match a filename iff the filename
2491 matches that wildcard according to shell rules. Only wildcards known
2492 by `sh' are supported."
2494 ;; Copy the initial run of non-special characters.
2497 ;; If no special characters, we're almost done.
2501 j)
2503 result
2520 ;; Found "[^". Insert a `\0' character
2521 ;; (which cannot happen in a filename)
2522 ;; into the character class, so that `^'
2523 ;; is not the first character after `[',
2524 ;; and thus non-special in a regexp.
2529 ;; I don't think `]' can appear in a
2530 ;; character class in a wildcard, but
2531 ;; let's be general here.
2538 i
2551 ;; Shell wildcards should match the entire filename,
2552 ;; not its part. Make the regexp say so.
2554 \f
2561 "/PROTECTION/SIZE/DATE/OWNER/WIDTH=(OWNER:10)"
2566 "Display a list of files in or matching DIRNAME, a la `ls'.
2567 DIRNAME is globbed by the shell if necessary.
2568 Prefix arg (second arg if noninteractive) means supply -l switch to `ls'.
2569 Actions controlled by variables `list-directory-brief-switches'
2570 and `list-directory-verbose-switches'."
2574 nil default-directory nil)
2575 pfx)))
2577 list-directory-brief-switches)))
2597 ;; insert-directory
2598 ;; - must insert _exactly_one_line_ describing FILE if WILDCARD and
2599 ;; FULL-DIRECTORY-P is nil.
2600 ;; The single line of output must display FILE's name as it was
2601 ;; given, namely, an absolute path name.
2602 ;; - must insert exactly one line for each file if WILDCARD or
2603 ;; FULL-DIRECTORY-P is t, plus one optional "total" line
2604 ;; before the file lines, plus optional text after the file lines.
2605 ;; Lines are delimited by "\n", so filenames containing "\n" are not
2606 ;; allowed.
2607 ;; File lines should display the basename.
2608 ;; - must be consistent with
2609 ;; - functions dired-move-to-filename, (these two define what a file line is)
2610 ;; dired-move-to-end-of-filename,
2611 ;; dired-between-files, (shortcut for (not (dired-move-to-filename)))
2612 ;; dired-insert-headerline
2613 ;; dired-after-subdir-garbage (defines what a "total" line is)
2614 ;; - variable dired-subdir-regexp
2616 "Insert directory listing for FILE, formatted according to SWITCHES.
2617 Leaves point after the inserted text.
2618 SWITCHES may be a string of options, or a list of strings.
2619 Optional third arg WILDCARD means treat FILE as shell wildcard.
2620 Optional fourth arg FULL-DIRECTORY-P means file is a directory and
2621 switches do not contain `d', so that a full listing is expected.
2623 This works by running a directory listing program
2624 whose name is in the variable `insert-directory-program'.
2625 If WILDCARD, it also runs the shell specified by `shell-file-name'."
2626 ;; We need the directory in order to find the right handler.
2631 wildcard full-directory-p)
2635 ;; Run ls in the directory of the file pattern we asked for.
2642 ;; Quote some characters that have special meanings in shells;
2643 ;; but don't quote the wildcards--we want them to be special.
2644 ;; We also currently don't quote the quoting characters
2645 ;; in case people want to use them explicitly to quote
2646 ;; wildcard characters.
2655 insert-directory-program
2656 " -d "
2658 switches
2660 " "
2661 pattern)))
2662 ;; SunOS 4.1.3, SVr4 and others need the "." to list the
2663 ;; directory if FILE is a symbolic link.
2665 insert-directory-program nil t nil
2671 ;; Split the switches at any spaces
2672 ;; so we can pass separate options as separate args.
2675 list)
2682 file))))))))))
2685 "Functions to call with no arguments to query about killing Emacs.
2686 If any of these functions returns nil, killing Emacs is cancelled.
2688 but `kill-emacs', the low level primitive, does not.
2692 "Offer to save each buffer, then kill this Emacs process.
2693 With prefix arg, silently save all file-visiting buffers, then kill."
2702 ;; process-list is not defined on VMS.
2704 active)
2709 val)
2714 ;; Query the user for other things, perhaps.
2717 \f
2741 ;;; files.el ends here