Dired Extra

This documents the “extra” features for GNU Emacs’s Dired Mode that are provided by the file dired-x.el.

Copyright © 1994–1995, 1999, 2001–2024 Free Software Foundation, Inc.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, with the Front-Cover Texts being “A GNU Manual”, and with the Back-Cover Texts as in (a) below. A copy of the license is included in the section entitled “GNU Free Documentation License”.

(a) The FSF’s Back-Cover Text is: “You have the freedom to copy and modify this GNU manual.”

Table of Contents


1 Introduction

This documents some extra features for GNU Emacs’s Dired Mode that are provided by dired-x.el (derived from Sebastian Kremer’s original dired-x.el).


1.1 Features

Some features provided by Dired Extra:

  1. Omitting uninteresting files from Dired listing (see Omitting Files in Dired).
  2. Running Dired command in non-Dired buffers (see Virtual Dired).
  3. Finding a file mentioned in a buffer (see Find File At Point).
  4. Commands using file marking (see Advanced Mark Commands).

dired-x.el binds some functions to keys in Dired Mode (see Key Index). Optionally, it also binds C-x C-f and C-x 4 C-f to dired-x-find-file and dired-x-find-file-other-window, respectively (see Find File At Point).


1.2 Technical Details

When dired-x.el is loaded, some standard Dired functions from dired.el and dired-aux.el offer additional features. dired-add-entry obeys Dired Omit mode (see Omitting Files in Dired), if it is active. dired-find-buffer-nocreate and dired-initial-position respect the value of dired-find-subdir (see Miscellaneous Commands).


2 Installation

This manual describes the Dired features provided by the file dired-x.el. To take advantage of these features, you must load the file and (optionally) set some variables.

In your ~/.emacs file, or in the system-wide initialization file default.el in the site-lisp directory, put

(with-eval-after-load 'dired
  (require 'dired-x)
  ;; Set dired-x global variables here.  For example:
  ;; (setq dired-x-hands-off-my-keys nil)
  ))
(add-hook 'dired-mode-hook
          (lambda ()
            ;; Set dired-x buffer-local variables here.  For example:
            ;; (dired-omit-mode 1)
            ))

This will load dired-x.el when Dired is first invoked (for example, when you first type C-x d).


2.1 Optional Installation File At Point

If you choose to have dired-x.el bind dired-x-find-file over find-file (see Find File At Point), then you will need to set dired-x-hands-off-my-keys. To do this, either set it before dired-x.el is loaded, or use M-x customize-variable, or call dired-x-bind-find-file after changing the value.

(with-eval-after-load 'dired
  ;; Bind dired-x-find-file.
  (setq dired-x-hands-off-my-keys nil)
  (require 'dired-x))

3 Omitting Files in Dired

Omitting a file means removing it from the directory listing. Omitting is useful for keeping Dired buffers free of “uninteresting” files (for instance, auto-save, auxiliary, backup, and revision control files) so that the user can concentrate on the interesting files. Like hidden files, omitted files are never seen by Dired. Omitting differs from hiding in several respects:

C-x M-o

(dired-omit-mode) Toggle between displaying and omitting “uninteresting” files.

* O

(dired-mark-omitted) Mark “uninteresting” files.

In order to make Dired Omit work you need to load dired-x after loading dired (see Installation) and then evaluate (dired-omit-mode 1) in some way (see Omitting Variables).


3.1 Omitting Variables

The following variables can be used to customize omitting.

Variable: dired-omit-mode

If non-nil, “uninteresting” files are not listed. The default is nil. Uninteresting files are files whose names match regexp dired-omit-files, plus files whose names end with extension in dired-omit-extensions. C-x M-o (dired-omit-mode) toggles its value, which is buffer-local. Put

(dired-omit-mode 1)

inside your dired-mode-hook to have omitting initially turned on in every Dired buffer (see Installation). You can then use C-x M-o to unomit in that buffer.

To enable omitting automatically only in certain directories you can add a directory local setting (see Directory Variables in The GNU Emacs manual) for Dired mode

((dired-mode . ((dired-omit-mode . t))))

to a .dir-locals.el file in that directory. You can use the command add-dir-local-variable to do this.

Variable: dired-omit-files

This buffer-local variable’s value is a regexp, a string. Files whose names match this regexp will not be displayed. This only has effect when dired-omit-mode’s value is t.

The default value omits the special directories . and .. and autosave files (plus other files ending in .) (see Examples of Omitting Various File Types).

Variable: dired-omit-extensions

If non-nil, this variable’s value is a list of extensions (strings) to omit from Dired listings. Its format is the same as that of completion-ignored-extensions. The default value is the elements of completion-ignored-extensions, dired-latex-unclean-extensions, dired-bibtex-unclean-extensions and dired-texinfo-unclean-extensions.

Variable: dired-omit-case-fold

Default: filesystem This variable controls whether file-name matching is case-insensitive. By default, when dired-omit-case-fold is set to filesystem, dired-omit-mode will match filenames and extensions case-sensitively on Dired buffers visiting case-sensitive filesystems, and case-insensitively on case-insensitive filesystems. Set it to nil to be always case-sensitive, and to t to be always case-insensitive.

Variable: dired-omit-localp

This variable determines the localp argument dired-omit-expunge passes to dired-get-filename. If it is no-dir, the default, omitting is much faster, but you can only match against the non-directory part of the file name. Set it to nil if you need to match the whole file name or t to match the file name relative to the buffer’s top-level directory.

Variable: dired-omit-marker-char

Temporary marker used by Dired to implement omitting. Should never be used as marker by the user or other packages. There is one exception to this rule: by adding

(setq dired-mark-keys "\C-o")
;; i.e., the value of dired-omit-marker-char
;; (which is not defined yet)

to your ~/.emacs, you can bind the C-o key to insert a C-o marker, thus causing these files to be omitted in addition to the usually omitted files. Unfortunately the files you omitted manually this way will show up again after reverting the buffer, unlike the others. The default value is C-o.


3.2 Examples of Omitting Various File Types

  • If you wish to avoid seeing RCS files and the RCS directory, then use
    (setq dired-omit-files
          (concat dired-omit-files "\\|^RCS$\\|,v$"))
    

    after loading dired-x (see Installation). This assumes dired-omit-localp has its default value of no-dir to make the ^-anchored matches work. As a slower alternative, with dired-omit-localp set to nil, you can use / instead of ^ in the regexp.

  • If you use tib, the bibliography program for use with TeX and LaTeX, and you want to omit the INDEX and the *-t.tex files, then use
    (setq dired-omit-files
          (concat dired-omit-files "\\|^INDEX$\\|-t\\.tex$"))
    

    after loading dired-x (see Installation).

  • If you do not wish to see ‘dot’ files (files starting with a .), then use
    (setq dired-omit-files
          (concat dired-omit-files "\\|^\\..+$"))
    

    after loading dired-x (see Installation). (Of course, a better way to achieve this particular goal is simply to omit ‘-a’ from dired-listing-switches.)


3.3 Some Technical Details of Omitting

Loading dired-x.el will install Dired Omit by putting dired-omit-expunge on your dired-after-readin-hook, and will call dired-extra-startup, which in turn calls dired-omit-startup in your dired-mode-hook.


4 Virtual Dired

Using Virtual Dired means putting a buffer with Dired-like contents in Dired mode. The files described by the buffer contents need not actually exist. This is useful if you want to peruse an ‘ls -lR’ output file, for example one you got from an FTP server. You can use all motion commands usually available in Dired. You can also use it to save a Dired buffer in a file and resume it in a later session.

Type M-x dired-virtual to put the current buffer into virtual Dired mode. You will be prompted for the top level directory of this buffer, with a default value guessed from the buffer contents. To convert the virtual to a real Dired buffer again, type g (which calls dired-virtual-revert) in the virtual Dired buffer and answer ‘y’. You don’t have to do this, though: you can relist single subdirectories using l (dired-do-redisplay) on the subdirectory headerline, leaving the buffer in virtual Dired mode all the time.

The function ‘dired-virtual-mode’ is specially designed to turn on virtual Dired mode from the auto-mode-alist. To edit all *.dired files automatically in virtual Dired mode, put this into your ~/.emacs:

(setq auto-mode-alist (cons '("[^/]\\.dired$" . dired-virtual-mode)
                              auto-mode-alist))

The regexp is a bit more complicated than usual to exclude .dired local-variable files.


5 Advanced Mark Commands

F

(dired-do-find-marked-files) Find all marked files at once displaying them simultaneously. If optional noselect is non-nil then just find the files but do not select. If you want to keep the Dired buffer displayed, type C-x 2 first. If you want just the marked files displayed and nothing else, type C-x 1 first.

The current window is split across all files marked, as evenly as possible. Remaining lines go to the bottom-most window. The number of files that can be displayed this way is restricted by the height of the current window and the variable window-min-height.

dired-mark-extension

Mark all files with a certain extension for use in later commands. A ‘.’ is automatically prepended to the string entered when not present. If invoked with prefix argument C-u, this command unmarks files instead. If called with the C-u C-u prefix, asks for a character to use as the marker, and marks files with it.

When called from Lisp, extension may also be a list of extensions and an optional argument marker-char specifies the marker used.

dired-mark-suffix

Mark all files with a certain suffix for use in later commands. A ‘.’ is not automatically prepended to the string entered, you must type it explicitly. This is different from dired-mark-extension which prepends a ‘.’ if not present. If invoked with prefix argument C-u, this command unmarks files instead. If called with the C-u C-u prefix, asks for a character to use as the marker, and marks files with it.

When called from Lisp, suffix may also be a list of suffixes and an optional argument marker-char specifies the marker used.

dired-flag-extension

Flag all files with a certain extension for deletion. A ‘.’ is not automatically prepended to the string entered.


5.1 Advanced Cleaning Functions

dired-clean-patch

Flag dispensable files created by the ‘patch’ program for deletion. See variable dired-patch-unclean-extensions.

dired-clean-tex

Flag dispensable files created by TeX, LaTeX, and ‘texinfo’ for deletion. See the following variables (see Advanced Cleaning Variables):

  • dired-tex-unclean-extensions
  • dired-texinfo-unclean-extensions
  • dired-latex-unclean-extensions
  • dired-bibtex-unclean-extensions
dired-very-clean-tex

Flag dispensable files created by TeX, LaTeX, ‘texinfo’, and *.dvi files for deletion.


5.2 Advanced Cleaning Variables

Variables used by the above cleaning commands (and in the default value for variable dired-omit-extensions, see Omitting Variables):

Variable: dired-patch-unclean-extensions

This variable specifies the list of extensions of dispensable files created by the ‘patch’ program. The default is (".rej" ".orig").

Variable: dired-tex-unclean-extensions

This variable specifies the list of extensions of dispensable files created by TeX. The default is (".toc" ".log" ".aux").

Variable: dired-texinfo-unclean-extensions

This variable holds the list of extensions of dispensable files created by ‘texinfo’. The default is (".cp" ".cps" ".fn" ".fns" ".ky" ".kys" ".pg" ".pgs" ".tp" ".tps" ".vr" ".vrs")

Variable: dired-latex-unclean-extensions

This variable specifies the list of extensions of dispensable files created by LaTeX. The default is (".idx" ".lof" ".lot" ".glo").

Variable: dired-bibtex-unclean-extensions

This variable specifies the list of extensions of dispensable files created by BibTeX. The default is (".blg" ".bbl").


5.3 Special Marking Function

M-(

Mark files for which predicate returns non-nil (dired-mark-sexp). With a prefix argument, unflag those files instead.

The predicate is a Lisp expression that can refer to the following symbols:

inode

[integer] the inode of the file (only for ‘ls -i’ output)

s

[integer] the size of the file for ‘ls -s’ output (usually in blocks or, with ‘-k’, in KBytes)

mode

[string] file permission bits, e.g., ‘-rw-r--r--

nlink

[integer] number of links to file

uid

[string] owner

gid

[string] group (If the gid is not displayed by ‘ls’, this will still be set (to the same as uid))

size

[integer] file size in bytes

time

[string] the time that ‘ls’ displays, e.g., ‘Feb 12 14:17

name

[string] the name of the file

sym

[string] if file is a symbolic link, the linked-to name, else ""

For example, use

(equal 0 size)

to mark all zero length files.

To find out all not yet compiled Emacs Lisp files in a directory, Dired all .el files in the lisp directory using the wildcard ‘*.el’. Then use M-( with

(not (file-exists-p (concat name "c")))

to mark all .el files without a corresponding .elc file.


6 Multiple Dired Directories and Non-Dired Commands

An Emacs buffer can have but one working directory, stored in the buffer-local variable default-directory. A Dired buffer may have several subdirectories inserted, but it still has only one working directory: that of the top-level Dired directory in that buffer. For some commands it is appropriate that they use the current Dired directory instead of default-directory, e.g., find-file and compile.

The command dired-smart-shell-command, bound to M-! in Dired buffers, is like shell-command, but it runs with default-directory bound to the current Dired directory.


7 Find File At Point

dired-x provides a method of visiting or editing a file mentioned in the buffer you are viewing (e.g., a mail buffer, a news article, a README file, etc.) or to test if that file exists. You can then modify this in the minibuffer after snatching the file name.

When installed dired-x will substitute dired-x-find-file for find-file (normally bound to C-x C-f) and dired-x-find-file-other-window for find-file-other-window (normally bound to C-x 4 C-f).

In order to use this feature, you will need to set dired-x-hands-off-my-keys to nil before loading dired-x (see Optional Installation File At Point).

dired-x-find-file

dired-x-find-file behaves exactly like find-file (normally bound to C-x C-f) unless a prefix argument is passed to the function in which case it will use the file name at point as a guess for the file to visit.

For example, if the buffer you were reading contained the words

Available via anonymous ftp in

   /roebling.poly.edu:/pub/lisp/crypt++.el.gz

then you could move your cursor to the line containing the ftp address and type C-u C-x C-f (the C-u is a universal argument). The minibuffer would read

Find file: /roebling.poly.edu:/pub/lisp/crypt++.el.gz

with the point after the last /. If you hit RET, emacs will visit the file at that address. This also works with files on your own computer.

dired-x-find-file-other-window

dired-x-find-file-other-window behaves exactly like find-file-other-window (normally bound to C-x 4 C-f) unless a prefix argument is used. See dired-x-find-file for more information.

dired-x-hands-off-my-keys

If set to t, then it means that dired-x should not bind dired-x-find-file over find-file on keyboard. Similarly, it should not bind dired-x-find-file-other-window over find-file-other-window. If you change this variable after dired-x.el is loaded then do M-x dired-x-bind-find-file. The default value of this variable is t; by default, the binding is not done. See Optional Installation File At Point.

dired-x-bind-find-file

A function, which can be called interactively or in your ~/.emacs file, that uses the value of dired-x-hands-off-my-keys to determine if dired-x-find-file should be bound over find-file and dired-x-find-file-other-window bound over find-file-other-window. See Optional Installation File At Point.


8 Miscellaneous Commands

Miscellaneous features not fitting anywhere else:

dired-find-subdir

Default: nil

If non-nil, Dired does not make a new buffer for a directory if it can be found (perhaps as subdirectory) in some existing Dired buffer.

If there are several Dired buffers for a directory, the most recently used is chosen.

Dired avoids switching to the current buffer, so that if you have a normal and a wildcard buffer for the same directory, C-x d RET will toggle between those two.

dired-vm

Bound to V if dired-bind-vm is t. Run VM on this file (assumed to be a UNIX mail folder).

If you give this command a prefix argument, it will visit the folder read-only.

If the variable dired-vm-read-only-folders is t, dired-vm will visit all folders read-only. If it is neither nil nor t, e.g., the symbol if-file-read-only, only files not writable by you are visited read-only.

If the variable dired-bind-vm is t, dired-vm will be bound to V. Otherwise, dired-bind-rmail will be bound.

dired-rmail

Bound to V if dired-bind-vm is nil. Run Rmail on this file (assumed to be mail folder in Rmail format).


9 Bugs

If you encounter a bug in this package, or wish to suggest an enhancement, then please use M-x report-emacs-bug to report it.


Appendix A GNU Free Documentation License

Version 1.3, 3 November 2008
Copyright © 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.
https://fsf.org/

Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
  1. PREAMBLE

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    The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.

  6. COMBINING DOCUMENTS

    You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.

    The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.

    In the combination, you must combine any sections Entitled “History” in the various original documents, forming one section Entitled “History”; likewise combine any sections Entitled “Acknowledgements”, and any sections Entitled “Dedications”. You must delete all sections Entitled “Endorsements.”

  7. COLLECTIONS OF DOCUMENTS

    You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.

    You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.

  8. AGGREGATION WITH INDEPENDENT WORKS

    A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an “aggregate” if the copyright resulting from the compilation is not used to limit the legal rights of the compilation’s users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.

    If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document’s Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.

  9. TRANSLATION

    Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.

    If a section in the Document is Entitled “Acknowledgements”, “Dedications”, or “History”, the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.

  10. TERMINATION

    You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.

    However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.

    Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.

    Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.

  11. FUTURE REVISIONS OF THIS LICENSE

    The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See https://www.gnu.org/licenses/.

    Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License “or any later version” applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Document.

  12. RELICENSING

    “Massive Multiauthor Collaboration Site” (or “MMC Site”) means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A “Massive Multiauthor Collaboration” (or “MMC”) contained in the site means any set of copyrightable works thus published on the MMC site.

    “CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.

    “Incorporate” means to publish or republish a Document, in whole or in part, as part of another Document.

    An MMC is “eligible for relicensing” if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008.

    The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.

ADDENDUM: How to use this License for your documents

To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:

  Copyright (C)  year  your name.
  Permission is granted to copy, distribute and/or modify this document
  under the terms of the GNU Free Documentation License, Version 1.3
  or any later version published by the Free Software Foundation;
  with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
  Texts.  A copy of the license is included in the section entitled ``GNU
  Free Documentation License''.

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with…Texts.” line with this:

    with the Invariant Sections being list their titles, with
    the Front-Cover Texts being list, and with the Back-Cover Texts
    being list.

If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.

If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.


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