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