(Making Backups, Auto-Saving): Remove @tindex entries.
[bpt/emacs.git] / man / dired.texi
1 @c This is part of the Emacs manual.
2 @c Copyright (C) 1985, 1986, 1987, 1993, 1994, 1995, 1997, 2000, 2001,
3 @c 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
4 @c See file emacs.texi for copying conditions.
5 @node Dired, Calendar/Diary, Rmail, Top
6 @chapter Dired, the Directory Editor
7 @cindex Dired
8 @cindex file management
9
10 Dired makes an Emacs buffer containing a listing of a directory, and
11 optionally some of its subdirectories as well. You can use the normal
12 Emacs commands to move around in this buffer, and special Dired commands
13 to operate on the files listed.
14
15 The Dired buffer is ``read-only,'' and inserting text in it is not
16 useful, so ordinary printing characters such as @kbd{d} and @kbd{x}
17 are redefined for special Dired commands. Some Dired commands
18 @dfn{mark} or @dfn{flag} the @dfn{current file} (that is, the file on
19 the current line); other commands operate on the marked files or on
20 the flagged files. You first mark certain files in order to operate
21 on all of them with on command.
22
23 The Dired-X package provides various extra features for Dired mode.
24 @xref{Top, Dired-X,,dired-x, Dired Extra Version 2 User's Manual}.
25
26 @menu
27 * Enter: Dired Enter. How to invoke Dired.
28 * Navigation: Dired Navigation. Special motion commands in the Dired buffer.
29 * Deletion: Dired Deletion. Deleting files with Dired.
30 * Flagging Many Files:: Flagging files based on their names.
31 * Visit: Dired Visiting. Other file operations through Dired.
32 * Marks vs Flags:: Flagging for deletion vs marking.
33 * Operating on Files:: How to copy, rename, print, compress, etc.
34 either one file or several files.
35 * Shell Commands in Dired:: Running a shell command on the marked files.
36 * Transforming File Names:: Using patterns to rename multiple files.
37 * Comparison in Dired:: Running `diff' by way of Dired.
38 * Subdirectories in Dired:: Adding subdirectories to the Dired buffer.
39 @ifnottex
40 * Subdir Switches:: Subdirectory switches in Dired.
41 @end ifnottex
42 * Subdirectory Motion:: Moving across subdirectories, and up and down.
43 * Hiding Subdirectories:: Making subdirectories visible or invisible.
44 * Updating: Dired Updating. Discarding lines for files of no interest.
45 * Find: Dired and Find. Using `find' to choose the files for Dired.
46 * Wdired:: Operating on files by editing the Dired buffer.
47 * Misc: Misc Dired Features. Various other features.
48 @end menu
49
50 @node Dired Enter
51 @section Entering Dired
52
53 @findex dired
54 @kindex C-x d
55 @vindex dired-listing-switches
56 To invoke Dired, do @kbd{C-x d} or @kbd{M-x dired}. The command
57 reads a directory name or wildcard file name pattern as a minibuffer
58 argument to specify the files to list. @kbd{C-x C-f} given a
59 directory name also invokes Dired. Where @code{dired} differs from
60 @code{list-directory} is that it puts the buffer into Dired mode, so
61 that the special commands of Dired are available.
62
63 The variable @code{dired-listing-switches} specifies the options to
64 give to @code{ls} for listing the directory; this string @emph{must}
65 contain @samp{-l}. If you use a numeric prefix argument with the
66 @code{dired} command, you can specify the @code{ls} switches with the
67 minibuffer before you enter the directory specification. No matter
68 how they are specified, the @code{ls} switches can include short
69 options (that is, single characters) requiring no arguments, and long
70 options (starting with @samp{--}) whose arguments are specified with
71 @samp{=}.
72
73 On MS-Windows and MS-DOS systems, Emacs @emph{emulates} @code{ls};
74 see @ref{ls in Lisp}, for options and peculiarities of that emulation.
75
76
77 @findex dired-other-window
78 @kindex C-x 4 d
79 @findex dired-other-frame
80 @kindex C-x 5 d
81 To display the Dired buffer in another window rather than in the
82 selected window, use @kbd{C-x 4 d} (@code{dired-other-window}) instead
83 of @kbd{C-x d}. @kbd{C-x 5 d} (@code{dired-other-frame}) uses a
84 separate frame to display the Dired buffer.
85
86 @node Dired Navigation
87 @section Navigation in the Dired Buffer
88
89 @kindex C-n @r{(Dired)}
90 @kindex C-p @r{(Dired)}
91 All the usual Emacs cursor motion commands are available in Dired
92 buffers. The keys @kbd{C-n} and @kbd{C-p} are redefined to put the
93 cursor at the beginning of the file name on the line, rather than at
94 the beginning of the line.
95
96 @kindex SPC @r{(Dired)}
97 For extra convenience, @key{SPC} and @kbd{n} in Dired are equivalent
98 to @kbd{C-n}. @kbd{p} is equivalent to @kbd{C-p}. (Moving by lines is
99 so common in Dired that it deserves to be easy to type.) @key{DEL}
100 (move up and unflag) is often useful simply for moving up.
101
102 @findex dired-goto-file
103 @kindex j @r{(Dired)}
104 @kbd{j} (@code{dired-goto-file}) moves point to the line that
105 describes a specified file or directory.
106
107 Some additional navigation commands are available when the Dired
108 buffer includes several directories. @xref{Subdirectory Motion}.
109
110 @node Dired Deletion
111 @section Deleting Files with Dired
112 @cindex flagging files (in Dired)
113 @cindex deleting files (in Dired)
114
115 One of the most frequent uses of Dired is to first @dfn{flag} files for
116 deletion, then delete the files that were flagged.
117
118 @table @kbd
119 @item d
120 Flag this file for deletion.
121 @item u
122 Remove deletion flag on this line.
123 @item @key{DEL}
124 Move point to previous line and remove the deletion flag on that line.
125 @item x
126 Delete the files that are flagged for deletion.
127 @end table
128
129 @kindex d @r{(Dired)}
130 @findex dired-flag-file-deletion
131 You can flag a file for deletion by moving to the line describing
132 the file and typing @kbd{d} (@code{dired-flag-file-deletion}). The
133 deletion flag is visible as a @samp{D} at the beginning of the line.
134 This command moves point to the next line, so that repeated @kbd{d}
135 commands flag successive files. A numeric argument serves as a repeat
136 count.
137
138 @kindex u @r{(Dired deletion)}
139 @kindex DEL @r{(Dired)}
140 The reason for flagging files for deletion, rather than deleting
141 files immediately, is to reduce the danger of deleting a file
142 accidentally. Until you direct Dired to delete the flagged files, you
143 can remove deletion flags using the commands @kbd{u} and @key{DEL}.
144 @kbd{u} (@code{dired-unmark}) works just like @kbd{d}, but removes
145 flags rather than making flags. @key{DEL}
146 (@code{dired-unmark-backward}) moves upward, removing flags; it is
147 like @kbd{u} with argument @minus{}1.
148
149 @kindex x @r{(Dired)}
150 @findex dired-do-flagged-delete
151 @cindex expunging (Dired)
152 To delete the flagged files, type @kbd{x}
153 (@code{dired-do-flagged-delete}). (This is also known as
154 @dfn{expunging}.) This command first displays a list of all the file
155 names flagged for deletion, and requests confirmation with @kbd{yes}.
156 If you confirm, Dired deletes the flagged files, then deletes their
157 lines from the text of the Dired buffer. The Dired buffer, with
158 somewhat fewer lines, remains selected.
159
160 If you answer @kbd{no} or quit with @kbd{C-g} when asked to confirm, you
161 return immediately to Dired, with the deletion flags still present in
162 the buffer, and no files actually deleted.
163
164 @cindex recursive deletion
165 @vindex dired-recursive-deletes
166 You can delete empty directories just like other files, but normally
167 Dired cannot delete directories that are nonempty. If the variable
168 @code{dired-recursive-deletes} is non-@code{nil}, then Dired can
169 delete nonempty directories including all their contents. That can
170 be somewhat risky.
171
172 @node Flagging Many Files
173 @section Flagging Many Files at Once
174 @cindex flagging many files for deletion (in Dired)
175
176 @table @kbd
177 @item #
178 Flag all auto-save files (files whose names start and end with @samp{#})
179 for deletion (@pxref{Auto Save}).
180
181 @item ~
182 Flag all backup files (files whose names end with @samp{~}) for deletion
183 (@pxref{Backup}).
184
185 @item &
186 Flag for deletion all files with certain kinds of names which suggest
187 you could easily create those files again.
188
189 @item .@: @r{(Period)}
190 Flag excess numeric backup files for deletion. The oldest and newest
191 few backup files of any one file are exempt; the middle ones are
192 flagged.
193
194 @item % d @var{regexp} @key{RET}
195 Flag for deletion all files whose names match the regular expression
196 @var{regexp}.
197 @end table
198
199 The @kbd{#}, @kbd{~}, @kbd{&}, and @kbd{.} commands flag many files for
200 deletion, based on their file names. These commands are useful
201 precisely because they do not themselves delete any files; you can
202 remove the deletion flags from any flagged files that you really wish to
203 keep.@refill
204
205 @kindex & @r{(Dired)}
206 @findex dired-flag-garbage-files
207 @vindex dired-garbage-files-regexp
208 @cindex deleting some backup files
209 @kbd{&} (@code{dired-flag-garbage-files}) flags files whose names
210 match the regular expression specified by the variable
211 @code{dired-garbage-files-regexp}. By default, this matches certain
212 files produced by @TeX{}, @samp{.bak} files, and the @samp{.orig} and
213 @samp{.rej} files produced by @code{patch}.
214
215 @kindex # @r{(Dired)}
216 @findex dired-flag-auto-save-files
217 @cindex deleting auto-save files
218 @kbd{#} (@code{dired-flag-auto-save-files}) flags for deletion all
219 files whose names look like auto-save files---that is, files whose
220 names begin and end with @samp{#}. @xref{Auto Save}.
221
222 @kindex ~ @r{(Dired)}
223 @findex dired-flag-backup-files
224 @kbd{~} (@code{dired-flag-backup-files}) flags for deletion all
225 files whose names say they are backup files---that is, files whose
226 names end in @samp{~}. @xref{Backup}.
227
228 @kindex . @r{(Dired)}
229 @vindex dired-kept-versions
230 @findex dired-clean-directory
231 @kbd{.} (period, @code{dired-clean-directory}) flags just some of the
232 backup files for deletion: all but the oldest few and newest few backups
233 of any one file. Normally @code{dired-kept-versions} (@strong{not}
234 @code{kept-new-versions}; that applies only when saving) specifies the
235 number of newest versions of each file to keep, and
236 @code{kept-old-versions} specifies the number of oldest versions to
237 keep.
238
239 Period with a positive numeric argument, as in @kbd{C-u 3 .},
240 specifies the number of newest versions to keep, overriding
241 @code{dired-kept-versions}. A negative numeric argument overrides
242 @code{kept-old-versions}, using minus the value of the argument to
243 specify the number of oldest versions of each file to keep.
244
245 @findex dired-flag-files-regexp
246 @kindex % d @r{(Dired)}
247 The @kbd{% d} command flags all files whose names match a specified
248 regular expression (@code{dired-flag-files-regexp}). Only the
249 non-directory part of the file name is used in matching. You can use
250 @samp{^} and @samp{$} to anchor matches. You can exclude certain
251 subdirectories from marking by hiding them while you use @kbd{% d}.
252 @xref{Hiding Subdirectories}.
253
254 @node Dired Visiting
255 @section Visiting Files in Dired
256
257 There are several Dired commands for visiting or examining the files
258 listed in the Dired buffer. All of them apply to the current line's
259 file; if that file is really a directory, these commands invoke Dired on
260 that subdirectory (making a separate Dired buffer).
261
262 @table @kbd
263 @item f
264 @kindex f @r{(Dired)}
265 @findex dired-find-file
266 Visit the file described on the current line, like typing @kbd{C-x C-f}
267 and supplying that file name (@code{dired-find-file}). @xref{Visiting}.
268
269 @item @key{RET}
270 @itemx e
271 @kindex RET @r{(Dired)}
272 @kindex e @r{(Dired)}
273 Equivalent to @kbd{f}.
274
275 @ignore @c This command seems too risky to document at all.
276 @item a
277 @kindex a @r{(Dired)}
278 @findex dired-find-alternate-file
279 Like @kbd{f}, but replaces the contents of the Dired buffer with
280 that of an alternate file or directory (@code{dired-find-alternate-file}).
281 @end ignore
282
283 @item o
284 @kindex o @r{(Dired)}
285 @findex dired-find-file-other-window
286 Like @kbd{f}, but uses another window to display the file's buffer
287 (@code{dired-find-file-other-window}). The Dired buffer remains visible
288 in the first window. This is like using @kbd{C-x 4 C-f} to visit the
289 file. @xref{Windows}.
290
291 @item C-o
292 @kindex C-o @r{(Dired)}
293 @findex dired-display-file
294 Visit the file described on the current line, and display the buffer in
295 another window, but do not select that window (@code{dired-display-file}).
296
297 @item Mouse-1
298 @itemx Mouse-2
299 @findex dired-mouse-find-file-other-window
300 Visit the file named by the line you click on
301 (@code{dired-mouse-find-file-other-window}). This uses another window
302 to display the file, like the @kbd{o} command.
303
304 @item v
305 @kindex v @r{(Dired)}
306 @findex dired-view-file
307 View the file described on the current line, using @kbd{M-x view-file}
308 (@code{dired-view-file}). Viewing a file with @code{view-file} is
309 like visiting it, but is slanted toward moving around in the file
310 conveniently and does not allow changing the file. @xref{Misc File
311 Ops, View File, Miscellaneous File Operations}.
312
313 @item ^
314 @kindex ^ @r{(Dired)}
315 @findex dired-up-directory
316 Visit the parent directory of the current directory
317 (@code{dired-up-directory}). This is equivalent to moving to the line
318 for @file{..} and typing @kbd{f} there.
319 @end table
320
321 @node Marks vs Flags
322 @section Dired Marks vs. Flags
323
324 @cindex marking many files (in Dired)
325 Instead of flagging a file with @samp{D}, you can @dfn{mark} the
326 file with some other character (usually @samp{*}). Most Dired
327 commands to operate on files use the files marked with @samp{*}. The
328 only command that operates on flagged flies is @kbd{x}, which expunges
329 them.
330
331 Here are some commands for marking with @samp{*}, for unmarking, and
332 for operating on marks. (@xref{Dired Deletion}, for commands to flag
333 and unflag files.)
334
335 @table @kbd
336 @item m
337 @itemx * m
338 @kindex m @r{(Dired)}
339 @kindex * m @r{(Dired)}
340 @findex dired-mark
341 Mark the current file with @samp{*} (@code{dired-mark}). With a numeric
342 argument @var{n}, mark the next @var{n} files starting with the current
343 file. (If @var{n} is negative, mark the previous @minus{}@var{n}
344 files.)
345
346 @item * *
347 @kindex * * @r{(Dired)}
348 @findex dired-mark-executables
349 @cindex marking executable files (in Dired)
350 Mark all executable files with @samp{*}
351 (@code{dired-mark-executables}). With a numeric argument, unmark all
352 those files.
353
354 @item * @@
355 @kindex * @@ @r{(Dired)}
356 @findex dired-mark-symlinks
357 @cindex marking symbolic links (in Dired)
358 Mark all symbolic links with @samp{*} (@code{dired-mark-symlinks}).
359 With a numeric argument, unmark all those files.
360
361 @item * /
362 @kindex * / @r{(Dired)}
363 @findex dired-mark-directories
364 @cindex marking subdirectories (in Dired)
365 Mark with @samp{*} all files which are directories, except for
366 @file{.} and @file{..} (@code{dired-mark-directories}). With a numeric
367 argument, unmark all those files.
368
369 @item * s
370 @kindex * s @r{(Dired)}
371 @findex dired-mark-subdir-files
372 Mark all the files in the current subdirectory, aside from @file{.}
373 and @file{..} (@code{dired-mark-subdir-files}).
374
375 @item u
376 @itemx * u
377 @kindex u @r{(Dired)}
378 @kindex * u @r{(Dired)}
379 @findex dired-unmark
380 Remove any mark on this line (@code{dired-unmark}).
381
382 @item @key{DEL}
383 @itemx * @key{DEL}
384 @kindex * DEL @r{(Dired)}
385 @findex dired-unmark-backward
386 @cindex unmarking files (in Dired)
387 Move point to previous line and remove any mark on that line
388 (@code{dired-unmark-backward}).
389
390 @item * !
391 @itemx U
392 @kindex * ! @r{(Dired)}
393 @kindex U @r{(Dired)}
394 @findex dired-unmark-all-marks
395 Remove all marks from all the files in this Dired buffer
396 (@code{dired-unmark-all-marks}).
397
398 @item * ? @var{markchar}
399 @itemx M-@key{DEL}
400 @kindex * ? @r{(Dired)}
401 @kindex M-DEL @r{(Dired)}
402 @findex dired-unmark-all-files
403 Remove all marks that use the character @var{markchar}
404 (@code{dired-unmark-all-files}). The argument is a single
405 character---do not use @key{RET} to terminate it. See the description
406 of the @kbd{* c} command below, which lets you replace one mark
407 character with another.
408
409 With a numeric argument, this command queries about each marked file,
410 asking whether to remove its mark. You can answer @kbd{y} meaning yes,
411 @kbd{n} meaning no, or @kbd{!} to remove the marks from the remaining
412 files without asking about them.
413
414 @item * C-n
415 @itemx M-@}
416 @findex dired-next-marked-file
417 @kindex * C-n @r{(Dired)}
418 @kindex M-@} @r{(Dired)}
419 Move down to the next marked file (@code{dired-next-marked-file})
420 A file is ``marked'' if it has any kind of mark.
421
422 @item * C-p
423 @itemx M-@{
424 @findex dired-prev-marked-file
425 @kindex * C-p @r{(Dired)}
426 @kindex M-@{ @r{(Dired)}
427 Move up to the previous marked file (@code{dired-prev-marked-file})
428
429 @item t
430 @itemx * t
431 @kindex t @r{(Dired)}
432 @kindex * t @r{(Dired)}
433 @findex dired-toggle-marks
434 @cindex toggling marks (in Dired)
435 Toggle all marks (@code{dired-toggle-marks}): files marked with @samp{*}
436 become unmarked, and unmarked files are marked with @samp{*}. Files
437 marked in any other way are not affected.
438
439 @item * c @var{old-markchar} @var{new-markchar}
440 @kindex * c @r{(Dired)}
441 @findex dired-change-marks
442 Replace all marks that use the character @var{old-markchar} with marks
443 that use the character @var{new-markchar} (@code{dired-change-marks}).
444 This command is the primary way to create or use marks other than
445 @samp{*} or @samp{D}. The arguments are single characters---do not use
446 @key{RET} to terminate them.
447
448 You can use almost any character as a mark character by means of this
449 command, to distinguish various classes of files. If @var{old-markchar}
450 is a space (@samp{ }), then the command operates on all unmarked files;
451 if @var{new-markchar} is a space, then the command unmarks the files it
452 acts on.
453
454 To illustrate the power of this command, here is how to put @samp{D}
455 flags on all the files that have no marks, while unflagging all those
456 that already have @samp{D} flags:
457
458 @example
459 * c D t * c SPC D * c t SPC
460 @end example
461
462 This assumes that no files were already marked with @samp{t}.
463
464 @item % m @var{regexp} @key{RET}
465 @itemx * % @var{regexp} @key{RET}
466 @findex dired-mark-files-regexp
467 @kindex % m @r{(Dired)}
468 @kindex * % @r{(Dired)}
469 Mark (with @samp{*}) all files whose names match the regular expression
470 @var{regexp} (@code{dired-mark-files-regexp}). This command is like
471 @kbd{% d}, except that it marks files with @samp{*} instead of flagging
472 with @samp{D}.
473
474 Only the non-directory part of the file name is used in matching. Use
475 @samp{^} and @samp{$} to anchor matches. You can exclude
476 subdirectories by temporarily hiding them (@pxref{Hiding
477 Subdirectories}).
478
479 @item % g @var{regexp} @key{RET}
480 @findex dired-mark-files-containing-regexp
481 @kindex % g @r{(Dired)}
482 @cindex finding files containing regexp matches (in Dired)
483 Mark (with @samp{*}) all files whose @emph{contents} contain a match for
484 the regular expression @var{regexp}
485 (@code{dired-mark-files-containing-regexp}). This command is like
486 @kbd{% m}, except that it searches the file contents instead of the file
487 name.
488
489 @item C-x u
490 @itemx C-_
491 @itemx C-/
492 @kindex C-_ @r{(Dired)}
493 @findex dired-undo
494 Undo changes in the Dired buffer, such as adding or removing
495 marks (@code{dired-undo}). @emph{This command does not revert the
496 actual file operations, nor recover lost files!} It just undoes
497 changes in the buffer itself.
498
499 In some cases, using this after commands that operate on files can
500 cause trouble. For example, after renaming one or more files,
501 @code{dired-undo} restores the original names in the Dired buffer,
502 which gets the Dired buffer out of sync with the actual contents of
503 the directory.
504 @end table
505
506 @node Operating on Files
507 @section Operating on Files
508 @cindex operating on files in Dired
509
510 This section describes the basic Dired commands to operate on one file
511 or several files. All of these commands are capital letters; all of
512 them use the minibuffer, either to read an argument or to ask for
513 confirmation, before they act. All of them let you specify the
514 files to manipulate in these ways:
515
516 @itemize @bullet
517 @item
518 If you give the command a numeric prefix argument @var{n}, it operates
519 on the next @var{n} files, starting with the current file. (If @var{n}
520 is negative, the command operates on the @minus{}@var{n} files preceding
521 the current line.)
522
523 @item
524 Otherwise, if some files are marked with @samp{*}, the command operates
525 on all those files.
526
527 @item
528 Otherwise, the command operates on the current file only.
529 @end itemize
530
531 @noindent
532 Certain other Dired commands, such as @kbd{!} and the @samp{%}
533 commands, use the same conventions to decide which files to work on.
534
535 @vindex dired-dwim-target
536 @cindex two directories (in Dired)
537 Commands which ask for a destination directory, such as those which
538 copy and rename files or create links for them, try to guess the default
539 target directory for the operation. Normally, they suggest the Dired
540 buffer's default directory, but if the variable @code{dired-dwim-target}
541 is non-@code{nil}, and if there is another Dired buffer displayed in the
542 next window, that other buffer's directory is suggested instead.
543
544 Here are the file-manipulating Dired commands that operate on files.
545
546 @table @kbd
547 @findex dired-do-copy
548 @kindex C @r{(Dired)}
549 @cindex copying files (in Dired)
550 @item C @var{new} @key{RET}
551 Copy the specified files (@code{dired-do-copy}). The argument @var{new}
552 is the directory to copy into, or (if copying a single file) the new
553 name.
554
555 @vindex dired-copy-preserve-time
556 If @code{dired-copy-preserve-time} is non-@code{nil}, then copying
557 with this command preserves the modification time of the old file in
558 the copy.
559
560 @vindex dired-recursive-copies
561 @cindex recursive copying
562 The variable @code{dired-recursive-copies} controls whether to copy
563 directories recursively. The default is @code{nil}, which means that
564 directories cannot be copied.
565
566 @item D
567 @findex dired-do-delete
568 @kindex D @r{(Dired)}
569 Delete the specified files (@code{dired-do-delete}). Like the other
570 commands in this section, this command operates on the @emph{marked}
571 files, or the next @var{n} files. By contrast, @kbd{x}
572 (@code{dired-do-flagged-delete}) deletes all @dfn{flagged} files.
573
574 @findex dired-do-rename
575 @kindex R @r{(Dired)}
576 @cindex renaming files (in Dired)
577 @item R @var{new} @key{RET}
578 Rename the specified files (@code{dired-do-rename}). The argument
579 @var{new} is the directory to rename into, or (if renaming a single
580 file) the new name.
581
582 Dired automatically changes the visited file name of buffers associated
583 with renamed files so that they refer to the new names.
584
585 @findex dired-do-hardlink
586 @kindex H @r{(Dired)}
587 @cindex hard links (in Dired)
588 @item H @var{new} @key{RET}
589 Make hard links to the specified files (@code{dired-do-hardlink}). The
590 argument @var{new} is the directory to make the links in, or (if making
591 just one link) the name to give the link.
592
593 @findex dired-do-symlink
594 @kindex S @r{(Dired)}
595 @cindex symbolic links (creation in Dired)
596 @item S @var{new} @key{RET}
597 Make symbolic links to the specified files (@code{dired-do-symlink}).
598 The argument @var{new} is the directory to make the links in, or (if
599 making just one link) the name to give the link.
600
601 @findex dired-do-chmod
602 @kindex M @r{(Dired)}
603 @cindex changing file permissions (in Dired)
604 @item M @var{modespec} @key{RET}
605 Change the mode (also called ``permission bits'') of the specified files
606 (@code{dired-do-chmod}). This uses the @code{chmod} program, so
607 @var{modespec} can be any argument that @code{chmod} can handle.
608
609 @findex dired-do-chgrp
610 @kindex G @r{(Dired)}
611 @cindex changing file group (in Dired)
612 @item G @var{newgroup} @key{RET}
613 Change the group of the specified files to @var{newgroup}
614 (@code{dired-do-chgrp}).
615
616 @findex dired-do-chown
617 @kindex O @r{(Dired)}
618 @cindex changing file owner (in Dired)
619 @item O @var{newowner} @key{RET}
620 Change the owner of the specified files to @var{newowner}
621 (@code{dired-do-chown}). (On most systems, only the superuser can do
622 this.)
623
624 @vindex dired-chown-program
625 The variable @code{dired-chown-program} specifies the name of the
626 program to use to do the work (different systems put @code{chown} in
627 different places).
628
629 @findex dired-do-touch
630 @kindex T @r{(Dired)}
631 @cindex changing file time (in Dired)
632 @item T @var{timestamp} @key{RET}
633 Touch the specified files (@code{dired-do-touch}). This means
634 updating their modification times to the present time.
635
636 @findex dired-do-print
637 @kindex P @r{(Dired)}
638 @cindex printing files (in Dired)
639 @item P @var{command} @key{RET}
640 Print the specified files (@code{dired-do-print}). You must specify the
641 command to print them with, but the minibuffer starts out with a
642 suitable guess made using the variables @code{lpr-command} and
643 @code{lpr-switches} (the same variables that @code{lpr-buffer} uses;
644 @pxref{Printing}).
645
646 @findex dired-do-compress
647 @kindex Z @r{(Dired)}
648 @cindex compressing files (in Dired)
649 @item Z
650 Compress the specified files (@code{dired-do-compress}). If the file
651 appears to be a compressed file already, uncompress it instead.
652
653 @findex dired-do-load
654 @kindex L @r{(Dired)}
655 @cindex loading several files (in Dired)
656 @item L
657 Load the specified Emacs Lisp files (@code{dired-do-load}).
658 @xref{Lisp Libraries}.
659
660 @findex dired-do-byte-compile
661 @kindex B @r{(Dired)}
662 @cindex byte-compiling several files (in Dired)
663 @item B
664 Byte compile the specified Emacs Lisp files
665 (@code{dired-do-byte-compile}). @xref{Byte Compilation,, Byte
666 Compilation, elisp, The Emacs Lisp Reference Manual}.
667
668 @kindex A @r{(Dired)}
669 @findex dired-do-search
670 @cindex search multiple files (in Dired)
671 @item A @var{regexp} @key{RET}
672 Search all the specified files for the regular expression @var{regexp}
673 (@code{dired-do-search}).
674
675 This command is a variant of @code{tags-search}. The search stops at
676 the first match it finds; use @kbd{M-,} to resume the search and find
677 the next match. @xref{Tags Search}.
678
679 @kindex Q @r{(Dired)}
680 @findex dired-do-query-replace-regexp
681 @cindex search and replace in multiple files (in Dired)
682 @item Q @var{regexp} @key{RET} @var{to} @key{RET}
683 Perform @code{query-replace-regexp} on each of the specified files,
684 replacing matches for @var{regexp} with the string
685 @var{to} (@code{dired-do-query-replace-regexp}).
686
687 This command is a variant of @code{tags-query-replace}. If you exit the
688 query replace loop, you can use @kbd{M-,} to resume the scan and replace
689 more matches. @xref{Tags Search}.
690 @end table
691
692 @node Shell Commands in Dired
693 @section Shell Commands in Dired
694 @cindex shell commands, Dired
695
696 @findex dired-do-shell-command
697 @kindex ! @r{(Dired)}
698 @kindex X @r{(Dired)}
699 The Dired command @kbd{!} (@code{dired-do-shell-command}) reads a
700 shell command string in the minibuffer and runs that shell command on
701 all the specified files. (@kbd{X} is a synonym for @kbd{!}.) You can
702 specify the files to operate on in the usual ways for Dired commands
703 (@pxref{Operating on Files}).
704
705 The working directory for the shell command is the top-level directory
706 of the Dired buffer.
707
708 There are two ways of applying a shell command to multiple files:
709
710 @itemize @bullet
711 @item
712 If you use @samp{*} surrounded by whitespace in the shell command,
713 then the command runs just once, with the list of file names
714 substituted for the @samp{*}. The order of file names is the order of
715 appearance in the Dired buffer.
716
717 Thus, @kbd{! tar cf foo.tar * @key{RET}} runs @code{tar} on the entire
718 list of file names, putting them into one tar file @file{foo.tar}.
719
720 If you want to use @samp{*} as a shell wildcard with whitespace around
721 it, write @samp{*""}. In the shell, this is equivalent to @samp{*};
722 but since the @samp{*} is not surrounded by whitespace, Dired does
723 not treat it specially.
724
725 @item
726 If the command string doesn't contain @samp{*} surrounded by
727 whitespace, then it runs once @emph{for each file}. Normally the file
728 name is added at the end.
729
730 For example, @kbd{! uudecode @key{RET}} runs @code{uudecode} on each
731 file.
732
733 @item
734 However, if the command string contains @samp{?} surrounded by
735 whitespace, the current file name is substituted for @samp{?} (rather
736 than added at the end). You can use @samp{?} this way more than once
737 in the command, and the same file name replaces each occurrence.
738 @end itemize
739
740 To iterate over the file names in a more complicated fashion, use an
741 explicit shell loop. For example, here is how to uuencode each file,
742 making the output file name by appending @samp{.uu} to the input file
743 name:
744
745 @example
746 for file in * ; do uuencode "$file" "$file" >"$file".uu; done
747 @end example
748
749 The @kbd{!} command does not attempt to update the Dired buffer to
750 show new or modified files, because it doesn't understand shell
751 commands, and does not know what files the shell command changed. Use
752 the @kbd{g} command to update the Dired buffer (@pxref{Dired
753 Updating}).
754
755 @node Transforming File Names
756 @section Transforming File Names in Dired
757
758 This section describes Dired commands which alter file names in a
759 systematic way. Each command operates on some or all of the marked
760 files, using a new name made by transforming the existing name.
761
762 Like the basic Dired file-manipulation commands (@pxref{Operating on
763 Files}), the commands described here operate either on the next
764 @var{n} files, or on all files marked with @samp{*}, or on the current
765 file. (To mark files, use the commands described in @ref{Marks vs
766 Flags}.)
767
768 All of the commands described in this section work
769 @emph{interactively}: they ask you to confirm the operation for each
770 candidate file. Thus, you can select more files than you actually
771 need to operate on (e.g., with a regexp that matches many files), and
772 then filter the selected names by typing @kbd{y} or @kbd{n} when the
773 command prompts for confirmation.
774
775 @table @kbd
776 @findex dired-upcase
777 @kindex % u @r{(Dired)}
778 @cindex upcase file names
779 @item % u
780 Rename each of the selected files to an upper-case name
781 (@code{dired-upcase}). If the old file names are @file{Foo}
782 and @file{bar}, the new names are @file{FOO} and @file{BAR}.
783
784 @item % l
785 @findex dired-downcase
786 @kindex % l @r{(Dired)}
787 @cindex downcase file names
788 Rename each of the selected files to a lower-case name
789 (@code{dired-downcase}). If the old file names are @file{Foo} and
790 @file{bar}, the new names are @file{foo} and @file{bar}.
791
792 @item % R @var{from} @key{RET} @var{to} @key{RET}
793 @kindex % R @r{(Dired)}
794 @findex dired-do-rename-regexp
795 @itemx % C @var{from} @key{RET} @var{to} @key{RET}
796 @kindex % C @r{(Dired)}
797 @findex dired-do-copy-regexp
798 @itemx % H @var{from} @key{RET} @var{to} @key{RET}
799 @kindex % H @r{(Dired)}
800 @findex dired-do-hardlink-regexp
801 @itemx % S @var{from} @key{RET} @var{to} @key{RET}
802 @kindex % S @r{(Dired)}
803 @findex dired-do-symlink-regexp
804 These four commands rename, copy, make hard links and make soft links,
805 in each case computing the new name by regular-expression substitution
806 from the name of the old file.
807 @end table
808
809 The four regular-expression substitution commands effectively
810 perform a search-and-replace on the selected file names. They read
811 two arguments: a regular expression @var{from}, and a substitution
812 pattern @var{to}; they match each ``old'' file name against
813 @var{from}, and then replace the matching part with @var{to}. You can
814 use @samp{\&} and @samp{\@var{digit}} in @var{to} to refer to all or
815 part of what the pattern matched in the old file name, as in
816 @code{replace-regexp} (@pxref{Regexp Replace}). If the regular
817 expression matches more than once in a file name, only the first match
818 is replaced.
819
820 For example, @kbd{% R ^.*$ @key{RET} x-\& @key{RET}} renames each
821 selected file by prepending @samp{x-} to its name. The inverse of this,
822 removing @samp{x-} from the front of each file name, is also possible:
823 one method is @kbd{% R ^x-\(.*\)$ @key{RET} \1 @key{RET}}; another is
824 @kbd{% R ^x- @key{RET} @key{RET}}. (Use @samp{^} and @samp{$} to anchor
825 matches that should span the whole file name.)
826
827 Normally, the replacement process does not consider the files'
828 directory names; it operates on the file name within the directory. If
829 you specify a numeric argument of zero, then replacement affects the
830 entire absolute file name including directory name. (A non-zero
831 argument specifies the number of files to operate on.)
832
833 You may want to select the set of files to operate on using the same
834 regexp @var{from} that you will use to operate on them. To do this,
835 mark those files with @kbd{% m @var{from} @key{RET}}, then use the
836 same regular expression in the command to operate on the files. To
837 make this more convenient, the @kbd{%} commands to operate on files
838 use the last regular expression specified in any @kbd{%} command as a
839 default.
840
841 @node Comparison in Dired
842 @section File Comparison with Dired
843 @cindex file comparison (in Dired)
844 @cindex compare files (in Dired)
845
846 Here are two Dired commands that compare specified files using
847 @code{diff}. They show the output in a buffer using Diff mode
848 (@pxref{Comparing Files}).
849
850 @table @kbd
851 @item =
852 @findex dired-diff
853 @kindex = @r{(Dired)}
854 Compare the current file (the file at point) with another file (the
855 file at the mark) using the @code{diff} program (@code{dired-diff}).
856 The file at the mark is the first argument of @code{diff}, and the
857 file at point is the second argument. This refers to the ordinary
858 Emacs mark, not Dired marks; use @kbd{C-@key{SPC}}
859 (@code{set-mark-command}) to set the mark at the first file's line
860 (@pxref{Setting Mark}).
861
862 @findex dired-backup-diff
863 @kindex M-= @r{(Dired)}
864 @item M-=
865 Compare the current file with its latest backup file
866 (@code{dired-backup-diff}). If the current file is itself a backup,
867 compare it with the file it is a backup of; this way, you can compare
868 a file with any one of its backups.
869
870 The backup file is the first file given to @code{diff}.
871 @end table
872
873 @node Subdirectories in Dired
874 @section Subdirectories in Dired
875 @cindex subdirectories in Dired
876 @cindex expanding subdirectories in Dired
877
878 A Dired buffer displays just one directory in the normal case;
879 but you can optionally include its subdirectories as well.
880
881 The simplest way to include multiple directories in one Dired buffer is
882 to specify the options @samp{-lR} for running @code{ls}. (If you give a
883 numeric argument when you run Dired, then you can specify these options
884 in the minibuffer.) That produces a recursive directory listing showing
885 all subdirectories at all levels.
886
887 More often, you will want to show only specific subdirectories. You
888 can do this with the @kbd{i} command:
889
890 @table @kbd
891 @findex dired-maybe-insert-subdir
892 @kindex i @r{(Dired)}
893 @item i
894 @cindex inserted subdirectory (Dired)
895 @cindex in-situ subdirectory (Dired)
896 Insert the contents of a subdirectory later in the buffer.
897 @end table
898
899 Use the @kbd{i} (@code{dired-maybe-insert-subdir}) command on a line
900 that describes a file which is a directory. It inserts the contents of
901 that directory into the same Dired buffer, and moves there. Inserted
902 subdirectory contents follow the top-level directory of the Dired
903 buffer, just as they do in @samp{ls -lR} output.
904
905 If the subdirectory's contents are already present in the buffer, the
906 @kbd{i} command just moves to it.
907
908 In either case, @kbd{i} sets the Emacs mark before moving, so @kbd{C-u
909 C-@key{SPC}} takes you back to the old position in the buffer (the line
910 describing that subdirectory).
911
912 Use the @kbd{l} command (@code{dired-do-redisplay}) to update the
913 subdirectory's contents. Use @kbd{C-u k} on the subdirectory header
914 line to delete the subdirectory. @xref{Dired Updating}.
915
916 @ifnottex
917 @include dired-xtra.texi
918 @end ifnottex
919
920 @node Subdirectory Motion
921 @section Moving Over Subdirectories
922
923 When a Dired buffer lists subdirectories, you can use the page motion
924 commands @kbd{C-x [} and @kbd{C-x ]} to move by entire directories
925 (@pxref{Pages}).
926
927 @cindex header line (Dired)
928 @cindex directory header lines
929 The following commands move across, up and down in the tree of
930 directories within one Dired buffer. They move to @dfn{directory header
931 lines}, which are the lines that give a directory's name, at the
932 beginning of the directory's contents.
933
934 @table @kbd
935 @findex dired-next-subdir
936 @kindex C-M-n @r{(Dired)}
937 @item C-M-n
938 Go to next subdirectory header line, regardless of level
939 (@code{dired-next-subdir}).
940
941 @findex dired-prev-subdir
942 @kindex C-M-p @r{(Dired)}
943 @item C-M-p
944 Go to previous subdirectory header line, regardless of level
945 (@code{dired-prev-subdir}).
946
947 @findex dired-tree-up
948 @kindex C-M-u @r{(Dired)}
949 @item C-M-u
950 Go up to the parent directory's header line (@code{dired-tree-up}).
951
952 @findex dired-tree-down
953 @kindex C-M-d @r{(Dired)}
954 @item C-M-d
955 Go down in the directory tree, to the first subdirectory's header line
956 (@code{dired-tree-down}).
957
958 @findex dired-prev-dirline
959 @kindex < @r{(Dired)}
960 @item <
961 Move up to the previous directory-file line (@code{dired-prev-dirline}).
962 These lines are the ones that describe a directory as a file in its
963 parent directory.
964
965 @findex dired-next-dirline
966 @kindex > @r{(Dired)}
967 @item >
968 Move down to the next directory-file line (@code{dired-prev-dirline}).
969 @end table
970
971 @node Hiding Subdirectories
972 @section Hiding Subdirectories
973
974 @cindex hiding in Dired (Dired)
975 @dfn{Hiding} a subdirectory means to make it invisible, except for its
976 header line.
977
978 @table @kbd
979 @item $
980 @findex dired-hide-subdir
981 @kindex $ @r{(Dired)}
982 Hide or reveal the subdirectory that point is in, and move point to the
983 next subdirectory (@code{dired-hide-subdir}). A numeric argument serves
984 as a repeat count.
985
986 @item M-$
987 @findex dired-hide-all
988 @kindex M-$ @r{(Dired)}
989 Hide all subdirectories in this Dired buffer, leaving only their header
990 lines (@code{dired-hide-all}). Or, if any subdirectory is currently
991 hidden, make all subdirectories visible again. You can use this command
992 to get an overview in very deep directory trees or to move quickly to
993 subdirectories far away.
994 @end table
995
996 Ordinary Dired commands never consider files inside a hidden
997 subdirectory. For example, the commands to operate on marked files
998 ignore files in hidden directories even if they are marked. Thus you
999 can use hiding to temporarily exclude subdirectories from operations
1000 without having to remove the Dired marks on files in those
1001 subdirectories.
1002
1003 @node Dired Updating
1004 @section Updating the Dired Buffer
1005 @cindex updating Dired buffer
1006 @cindex refreshing displayed files
1007
1008 This section describes commands to update the Dired buffer to reflect
1009 outside (non-Dired) changes in the directories and files, and to delete
1010 part of the Dired buffer.
1011
1012 @table @kbd
1013 @item g
1014 Update the entire contents of the Dired buffer (@code{revert-buffer}).
1015
1016 @item l
1017 Update the specified files (@code{dired-do-redisplay}). You specify the
1018 files for @kbd{l} in the same way as for file operations.
1019
1020 @item k
1021 Delete the specified @emph{file lines}---not the files, just the lines
1022 (@code{dired-do-kill-lines}).
1023
1024 @item s
1025 Toggle between alphabetical order and date/time order
1026 (@code{dired-sort-toggle-or-edit}).
1027
1028 @item C-u s @var{switches} @key{RET}
1029 Refresh the Dired buffer using @var{switches} as
1030 @code{dired-listing-switches}.
1031 @end table
1032
1033 @kindex g @r{(Dired)}
1034 @findex revert-buffer @r{(Dired)}
1035 Type @kbd{g} (@code{revert-buffer}) to update the contents of the
1036 Dired buffer, based on changes in the files and directories listed.
1037 This preserves all marks except for those on files that have vanished.
1038 Hidden subdirectories are updated but remain hidden.
1039
1040 @kindex l @r{(Dired)}
1041 @findex dired-do-redisplay
1042 To update only some of the files, type @kbd{l}
1043 (@code{dired-do-redisplay}). Like the Dired file-operating commands,
1044 this command operates on the next @var{n} files (or previous
1045 @minus{}@var{n} files), or on the marked files if any, or on the
1046 current file. Updating the files means reading their current status,
1047 then updating their lines in the buffer to indicate that status.
1048
1049 If you use @kbd{l} on a subdirectory header line, it updates the
1050 contents of the corresponding subdirectory.
1051
1052 @kindex k @r{(Dired)}
1053 @findex dired-do-kill-lines
1054 To delete the specified @emph{file lines} from the buffer---not
1055 delete the files---type @kbd{k} (@code{dired-do-kill-lines}). Like
1056 the file-operating commands, this command operates on the next @var{n}
1057 files, or on the marked files if any; but it does not operate on the
1058 current file as a last resort.
1059
1060 If you use @kbd{k} with a numeric prefix argument to kill the line
1061 for a file that is a directory, which you have inserted in the Dired
1062 buffer as a subdirectory, it deletes that subdirectory from the buffer
1063 as well. Typing @kbd{C-u k} on the header line for a subdirectory
1064 also deletes the subdirectory from the Dired buffer.
1065
1066 The @kbd{g} command brings back any individual lines that you have
1067 killed in this way, but not subdirectories---you must use @kbd{i} to
1068 reinsert a subdirectory.
1069
1070 @cindex Dired sorting
1071 @cindex sorting Dired buffer
1072 @kindex s @r{(Dired)}
1073 @findex dired-sort-toggle-or-edit
1074 The files in a Dired buffers are normally listed in alphabetical order
1075 by file names. Alternatively Dired can sort them by date/time. The
1076 Dired command @kbd{s} (@code{dired-sort-toggle-or-edit}) switches
1077 between these two sorting modes. The mode line in a Dired buffer
1078 indicates which way it is currently sorted---by name, or by date.
1079
1080 @kbd{C-u s @var{switches} @key{RET}} lets you specify a new value for
1081 @code{dired-listing-switches}.
1082
1083 @node Dired and Find
1084 @section Dired and @code{find}
1085 @cindex @code{find} and Dired
1086
1087 You can select a set of files for display in a Dired buffer more
1088 flexibly by using the @code{find} utility to choose the files.
1089
1090 @findex find-name-dired
1091 To search for files with names matching a wildcard pattern use
1092 @kbd{M-x find-name-dired}. It reads arguments @var{directory} and
1093 @var{pattern}, and chooses all the files in @var{directory} or its
1094 subdirectories whose individual names match @var{pattern}.
1095
1096 The files thus chosen are displayed in a Dired buffer, in which the
1097 ordinary Dired commands are available.
1098
1099 @findex find-grep-dired
1100 If you want to test the contents of files, rather than their names,
1101 use @kbd{M-x find-grep-dired}. This command reads two minibuffer
1102 arguments, @var{directory} and @var{regexp}; it chooses all the files in
1103 @var{directory} or its subdirectories that contain a match for
1104 @var{regexp}. It works by running the programs @code{find} and
1105 @code{grep}. See also @kbd{M-x grep-find}, in @ref{Grep Searching}.
1106 Remember to write the regular expression for @code{grep}, not for Emacs.
1107 (An alternative method of showing files whose contents match a given
1108 regexp is the @kbd{% g @var{regexp}} command, see @ref{Marks vs Flags}.)
1109
1110 @findex find-dired
1111 The most general command in this series is @kbd{M-x find-dired}, which
1112 lets you specify any condition that @code{find} can test. It takes two
1113 minibuffer arguments, @var{directory} and @var{find-args}; it runs
1114 @code{find} in @var{directory}, passing @var{find-args} to tell
1115 @code{find} what condition to test. To use this command, you need to
1116 know how to use @code{find}.
1117
1118 @vindex find-ls-option
1119 The format of listing produced by these commands is controlled by the
1120 variable @code{find-ls-option}, whose default value specifies using
1121 options @samp{-ld} for @code{ls}. If your listings are corrupted, you
1122 may need to change the value of this variable.
1123
1124 @findex locate
1125 @findex locate-with-filter
1126 @cindex file database (locate)
1127 @vindex locate-command
1128 @kbd{M-x locate} provides a similar interface to the @code{locate}
1129 program. @kbd{M-x locate-with-filter} is similar, but keeps only files
1130 whose names match a given regular expression.
1131
1132 These buffers don't work entirely like ordinary Dired buffers: file
1133 operations work, but do not always automatically update the buffer.
1134 Reverting the buffer with @kbd{g} deletes all inserted subdirectories,
1135 and erases all flags and marks.
1136
1137 @node Wdired
1138 @section Editing the Dired Buffer
1139
1140 @cindex wdired mode
1141 @findex wdired-change-to-wdired-mode
1142 Wdired is a special mode that allows you to perform file operations
1143 by editing the Dired buffer directly (the ``W'' in ``Wdired'' stands
1144 for ``writable''.) To enter Wdired mode, type @kbd{M-x
1145 wdired-change-to-wdired-mode} while in a Dired buffer. Alternatively,
1146 use @samp{Edit File Names} in the @samp{Immediate} menu bar menu.
1147
1148 @findex wdired-finish-edit
1149 While in Wdired mode, you can rename files by editing the file names
1150 displayed in the Dired buffer. All the ordinary Emacs editing
1151 commands, including rectangle operations and @code{query-replace}, are
1152 available for this. Once you are done editing, type @kbd{C-c C-c}
1153 (@code{wdired-finish-edit}). This applies your changes and switches
1154 back to ordinary Dired mode.
1155
1156 Apart from simply renaming files, you can move a file to another
1157 directory by typing in the new file name (either absolute or
1158 relative). To mark a file for deletion, delete the entire file name.
1159 To change the target of a symbolic link, edit the link target name
1160 which appears next to the link name.
1161
1162 The rest of the text in the buffer, such as the file sizes and
1163 modification dates, is marked read-only, so you can't edit it.
1164 However, if you set @code{wdired-allow-to-change-permissions} to
1165 @code{t}, you can edit the file permissions. For example, you can
1166 change @samp{-rw-r--r--} to @samp{-rw-rw-rw-} to make a file
1167 world-writable. These changes also take effect when you type @kbd{C-c
1168 C-c}.
1169
1170 @node Misc Dired Features
1171 @section Other Dired Features
1172
1173 @kindex + @r{(Dired)}
1174 @findex dired-create-directory
1175 An unusual Dired file-operation command is @kbd{+}
1176 (@code{dired-create-directory}). This command reads a directory name,
1177 and creates the directory if it does not already exist.
1178
1179 @cindex Adding to the kill ring in Dired.
1180 @kindex w @r{(Dired)}
1181 @findex dired-copy-filename-as-kill
1182 The @kbd{w} command (@code{dired-copy-filename-as-kill}) puts the
1183 names of the marked (or next @var{n}) files into the kill ring, as if
1184 you had killed them with @kbd{C-w}. The names are separated by a space.
1185
1186 With a zero prefix argument, this uses the absolute file name of
1187 each marked file. With just @kbd{C-u} as the prefix argument, it uses
1188 file names relative to the Dired buffer's default directory. (This
1189 can still contain slashes if in a subdirectory.) As a special case,
1190 if point is on a directory headerline, @kbd{w} gives you the absolute
1191 name of that directory. Any prefix argument or marked files are
1192 ignored in this case.
1193
1194 The main purpose of this command is so that you can yank the file
1195 names into arguments for other Emacs commands. It also displays what
1196 it added to the kill ring, so you can use it to display the list of
1197 currently marked files in the echo area.
1198
1199 @findex dired-compare-directories
1200 The command @kbd{M-x dired-compare-directories} is used to compare
1201 the current Dired buffer with another directory. It marks all the files
1202 that are ``different'' between the two directories. It puts these marks
1203 in all Dired buffers where these files are listed, which of course includes
1204 the current buffer.
1205
1206 The default comparison method (used if you type @key{RET} at the
1207 prompt) is to compare just the file names---each file name that does
1208 not appear in the other directory is ``different''. You can specify
1209 more stringent comparisons by entering a Lisp expression, which can
1210 refer to the variables @code{size1} and @code{size2}, the respective
1211 file sizes; @code{mtime1} and @code{mtime2}, the last modification
1212 times in seconds, as floating point numbers; and @code{fa1} and
1213 @code{fa2}, the respective file attribute lists (as returned by the
1214 function @code{file-attributes}). This expression is evaluated for
1215 each pair of like-named files, and if the expression's value is
1216 non-@code{nil}, those files are considered ``different''.
1217
1218 For instance, the sequence @code{M-x dired-compare-directories
1219 @key{RET} (> mtime1 mtime2) @key{RET}} marks files newer in this
1220 directory than in the other, and marks files older in the other
1221 directory than in this one. It also marks files with no counterpart,
1222 in both directories, as always.
1223
1224 @cindex drag and drop, Dired
1225 On the X window system, Emacs supports the ``drag and drop''
1226 protocol. You can drag a file object from another program, and drop
1227 it onto a Dired buffer; this either moves, copies, or creates a link
1228 to the file in that directory. Precisely which action is taken is
1229 determined by the originating program. Dragging files out of a Dired
1230 buffer is currently not supported.
1231
1232 @ignore
1233 arch-tag: d105f9b9-fc1b-4c5f-a949-9b2cf3ca2fc1
1234 @end ignore