The GNU Emacs FAQ

This is the GNU Emacs FAQ, last updated on 22 June 2013.

This FAQ is maintained as a part of GNU Emacs. If you find any errors, or have any suggestions, please use M-x report-emacs-bug to report them.

This is the version of the FAQ distributed with Emacs 24.3, and mainly describes that version. Although there is some information on older versions, details about very old releases (now only of historical interest) have been removed. If you are interested in this, consult either the version of the FAQ distributed with older versions of Emacs, or the history of this document in the Emacs source repository.

Since Emacs releases are very stable, we recommend always running the latest release.

This FAQ is not updated very frequently. When you have a question about Emacs, the Emacs manual is often the best starting point.

Copyright © 2001–2013 Free Software Foundation, Inc.
Copyright © 1994, 1995, 1996, 1997, 1998, 1999, 2000 Reuven M. Lerner
Copyright © 1992, 1993 Steven Byrnes
Copyright © 1990, 1991, 1992 Joseph Brian Wells

This list of frequently asked questions about GNU Emacs with answers (“FAQ”) may be translated into other languages, transformed into other formats (e.g., Texinfo, Info, WWW, WAIS), and updated with new information.

The same conditions apply to any derivative of the FAQ as apply to the FAQ itself. Every copy of the FAQ must include this notice or an approved translation, information on who is currently maintaining the FAQ and how to contact them (including their e-mail address), and information on where the latest version of the FAQ is archived (including FTP information).

The FAQ may be copied and redistributed under these conditions, except that the FAQ may not be embedded in a larger literary work unless that work itself allows free copying and redistribution.

[This version has been heavily edited since it was included in the Emacs distribution.]

FAQ notation
General questions
Getting help
Status of Emacs
Common requests
Bugs and problems
Compiling and installing Emacs
Finding Emacs and related packages
Key bindings
Alternate character sets
Mail and news
Concept index

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1 FAQ notation

This chapter describes notation used in the GNU Emacs FAQ, as well as in the Emacs documentation. Consult this section if this is the first time you are reading the FAQ, or if you are confused by notation or terms used in the FAQ.

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1.1 What do these mean: C-h, C-M-a, <RET>, <ESC> a, etc.?

Key sequences longer than one key (and some single-key sequences) are written inside quotes or on lines by themselves, like this:

       M-x frobnicate-while-foo RET

Any real spaces in such a key sequence should be ignored; only <SPC> really means press the space key.

The ASCII code sent by C-x (except for C-?) is the value that would be sent by pressing just <x> minus 96 (or 64 for upper-case <X>) and will be from 0 to 31. On Unix and GNU/Linux terminals, the ASCII code sent by M-x is the sum of 128 and the ASCII code that would be sent by pressing just <x>. Essentially, <Control> turns off bits 5 and 6 and <Meta> turns on bit 71.

C-? (aka <DEL>) is ASCII code 127. It is a misnomer to call C-? a “control” key, since 127 has both bits 5 and 6 turned ON. Also, on very few keyboards does C-? generate ASCII code 127.

See Keys.

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1.2 What does M-x command mean?

M-x command means type M-x, then type the name of the command, then type <RET>. (See Basic keys, if you're not sure what M-x and <RET> mean.)

M-x (by default) invokes the command execute-extended-command. This command allows you to run any Emacs command if you can remember the command's name. If you can't remember the command's name, you can type <TAB> and <SPC> for completion, <?> for a list of possibilities, and M-p and M-n (or up-arrow and down-arrow) to see previous commands entered. An Emacs command is an interactive Emacs function.

Your system administrator may have bound other key sequences to invoke execute-extended-command. A function key labeled Do is a good candidate for this, on keyboards that have such a key.

If you need to run non-interactive Emacs functions, see Evaluating Emacs Lisp code.

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1.3 How do I read topic XXX in the Emacs manual?

When we refer you to some topic in the Emacs manual, you can read this manual node inside Emacs (assuming nothing is broken) by typing C-h i m emacs <RET> m topic <RET>.

This invokes Info, the GNU hypertext documentation browser. If you don't already know how to use Info, type <?> from within Info.

If we refer to topic:subtopic, type C-h i m emacs <RET> m topic <RET> m subtopic <RET>.

If these commands don't work as expected, your system administrator may not have installed the Info files, or may have installed them improperly. In this case you should complain.

If you are reading this FAQ in Info, you can simply press <RET> on a reference to follow it.

See Getting a printed manual, if you would like a paper copy of the Emacs manual.

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1.4 What are src/config.h, site-lisp/default.el, etc.?

These are files that come with Emacs. The Emacs distribution is divided into subdirectories; e.g., etc, lisp, and src. Some of these (e.g., etc and lisp) are present both in an installed Emacs and in the sources, but some (e.g., src) are only found in the sources.

If you use Emacs, but don't know where it is kept on your system, start Emacs, then type C-h v data-directory <RET>. The directory name displayed by this will be the full pathname of the installed etc directory. (This full path is recorded in the Emacs variable data-directory, and C-h v displays the value and the documentation of a variable.)

The location of your Info directory (i.e., where Info documentation is stored) is kept in the variable Info-default-directory-list. Use C-h v Info-default-directory-list <RET> to see the value of this variable, which will be a list of directory names. The last directory in that list is probably where most Info files are stored. By default, Emacs Info documentation is placed in /usr/local/share/info.

For information on some of the files in the etc directory, see Informational files for Emacs.

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1.5 What are FSF, LPF, GNU, RMS, FTP, and GPL?

FSF
Free Software Foundation
LPF
League for Programming Freedom
GNU
GNU's Not Unix
RMS
Richard Matthew Stallman
FTP
File Transfer Protocol
GPL
GNU General Public License

Avoid confusing the FSF and the LPF. The LPF opposes look-and-feel copyrights and software patents. The FSF aims to make high quality free software available for everyone.

The word “free” in the title of the Free Software Foundation refers to “freedom,” not “zero cost.” Anyone can charge any price for GPL-covered software that they want to. However, in practice, the freedom enforced by the GPL leads to low prices, because you can always get the software for less money from someone else, since everyone has the right to resell or give away GPL-covered software.

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2 General questions

This chapter contains general questions having to do with Emacs, the Free Software Foundation, and related organizations.

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2.1 What is the LPF?

The LPF opposes the expanding danger of software patents and look-and-feel copyrights. More information on the LPF's views is available at the LPF home page.

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2.2 What is the real legal meaning of the GNU copyleft?

The real legal meaning of the GNU General Public License (copyleft) will only be known if and when a judge rules on its validity and scope. There has never been a copyright infringement case involving the GPL to set any precedents. Although legal actions have been brought against companies for violating the terms of the GPL, so far all have been settled out of court (in favor of the plaintiffs). Please take any discussion regarding this issue to the newsgroup news:gnu.misc.discuss, which was created to hold the extensive flame wars on the subject.

RMS writes:

The legal meaning of the GNU copyleft is less important than the spirit, which is that Emacs is a free software project and that work pertaining to Emacs should also be free software. “Free” means that all users have the freedom to study, share, change and improve Emacs. To make sure everyone has this freedom, pass along source code when you distribute any version of Emacs or a related program, and give the recipients the same freedom that you enjoyed.

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2.3 What are appropriate messages for the various Emacs newsgroups?

The file etc/MAILINGLISTS describes the purpose of each GNU mailing list (see Informational files for Emacs). For those lists which are gatewayed with newsgroups, it lists both the newsgroup name and the mailing list address. The Emacs mailing lists are also described at the Emacs Savannah page.

The newsgroup news:comp.emacs is for discussion of Emacs programs in general. The newsgroup news:gnu.emacs.help is specifically for GNU Emacs. It therefore makes no sense to cross-post to both groups, since only one can be appropriate to any question.

Messages advocating “non-free” software are considered unacceptable on any of the gnu.* newsgroups except for news:gnu.misc.discuss, which was created to hold the extensive flame-wars on the subject. “Non-free” software includes any software for which the end user can't freely modify the source code and exchange enhancements. Be careful to remove the gnu.* groups from the ‘Newsgroups:’ line when posting a followup that recommends such software.

news:gnu.emacs.bug is a place where bug reports appear, but avoid posting bug reports to this newsgroup directly (see Reporting bugs).

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2.4 Where can I get old postings to news:gnu.emacs.help and other GNU groups?

The FSF has maintained archives of all of the GNU mailing lists for many years, although there may be some unintentional gaps in coverage. The archive can be browsed over the web at the GNU mail archive. Raw files can be downloaded from ftp://lists.gnu.org/.

Web-based Usenet search services, such as Google, also archive the gnu.* groups.

You can also read the archives of the gnu.* groups and post new messages at Gmane. Gmane is a service that presents mailing lists as newsgroups (even those without a traditional mail-to-news gateway).

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2.5 Where should I report bugs and other problems with Emacs?

The correct way to report Emacs bugs is to use the command M-x report-emacs-bug. It sets up a mail buffer with the essential information and the correct e-mail address, which is bug-gnu-emacs@gnu.org for the released versions of Emacs. Anything sent to bug-gnu-emacs@gnu.org also appears in the newsgroup news:gnu.emacs.bug, but please use e-mail instead of news to submit the bug report. This ensures a reliable return address so you can be contacted for further details.

Be sure to read the “Bugs” section of the Emacs manual before reporting a bug! The manual describes in detail how to submit a useful bug report (see Reporting Bugs). (See Emacs manual, if you don't know how to read the manual.)

RMS says:

Sending bug reports to help-gnu-emacs@gnu.org (which has the effect of posting on news:gnu.emacs.help) is undesirable because it takes the time of an unnecessarily large group of people, most of whom are just users and have no idea how to fix these problem. bug-gnu-emacs@gnu.org reaches a much smaller group of people who are more likely to know what to do and have expressed a wish to receive more messages about Emacs than the others.

RMS says it is sometimes fine to post to news:gnu.emacs.help:

If you have reported a bug and you don't hear about a possible fix, then after a suitable delay (such as a week) it is okay to post on gnu.emacs.help asking if anyone can help you.

If you are unsure whether you have found a bug, consider the following non-exhaustive list, courtesy of RMS:

If Emacs crashes, that is a bug. If Emacs gets compilation errors while building, that is a bug. If Emacs crashes while building, that is a bug. If Lisp code does not do what the documentation says it does, that is a bug.

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2.6 How do I unsubscribe from a mailing list?

If you are receiving a GNU mailing list named list, you should be able to unsubscribe from it by sending a request to the address list-request@gnu.org. Mailing lists mails normally contain information in either the message header (‘List-Unsubscribe:’) or as a footer that tells you how to unsubscribe.

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2.7 How do I contact the FSF?

For up-to-date information, see the FSF contact web-page. You can send general correspondence to info@fsf.org.

For details on how to order items directly from the FSF, see the FSF on-line store.

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3 Getting help

This chapter tells you how to get help with Emacs.

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3.1 I'm just starting Emacs; how do I do basic editing?

Type C-h t to invoke the self-paced tutorial. Just typing C-h enters the help system. Starting with Emacs 22, the tutorial is available in many foreign languages such as French, German, Japanese, Russian, etc. Use M-x help-with-tutorial-spec-language <RET> to choose your language and start the tutorial.

Your system administrator may have changed C-h to act like <DEL> to deal with local keyboards. You can use M-x help-for-help instead to invoke help. To discover what key (if any) invokes help on your system, type M-x where-is <RET> help-for-help <RET>. This will print a comma-separated list of key sequences in the echo area. Ignore the last character in each key sequence listed. Each of the resulting key sequences (e.g., <F1> is common) invokes help.

Emacs help works best if it is invoked by a single key whose value should be stored in the variable help-char.

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3.2 How do I find out how to do something in Emacs?

There are several methods for finding out how to do things in Emacs.

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3.3 How do I get a printed copy of the Emacs manual?

You can order a printed copy of the Emacs manual from the FSF. For details see the FSF on-line store.

The full Texinfo source for the manual also comes in the doc/emacs directory of the Emacs distribution, if you're daring enough to try to print out this several-hundred-page manual yourself (see Printing a Texinfo file).

If you absolutely have to print your own copy, and you don't have TeX, you can get a PostScript or PDF (or HTML) version from

http://www.gnu.org/software/emacs/manual/

See Learning how to do something, for how to view the manual from Emacs.

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3.4 Where can I get documentation on Emacs Lisp?

Within Emacs, you can type C-h f to get the documentation for a function, C-h v for a variable.

For more information, the Emacs Lisp Reference Manual is available in Info format (see Emacs Lisp).

You can also order a hardcopy of the manual from the FSF, for details see the FSF on-line store. (This manual is not always in print.)

An HTML version of the Emacs Lisp Reference Manual is available at

http://www.gnu.org/software/emacs/elisp-manual/elisp.html

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3.5 How do I install a piece of Texinfo documentation?

Emacs releases come with pre-built Info files, and the normal install process places them in the correct location. This is true for most applications that provide Info files. The following section is only relevant if you want to install extra Info files by hand.

First, you must turn the Texinfo source files into Info files. You may do this using the stand-alone makeinfo program, available as part of the Texinfo package at

http://www.gnu.org/software/texinfo/

For information about the Texinfo format, read the Texinfo manual which comes with the Texinfo package. This manual also comes installed in Info format, so you can read it from Emacs; type C-h i m texinfo <RET>.

Alternatively, you could use the Emacs command M-x texinfo-format-buffer, after visiting the Texinfo source file of the manual you want to convert.

Neither texinfo-format-buffer nor makeinfo installs the resulting Info files in Emacs's Info tree. To install Info files, perform these steps:

  1. Move the files to the info directory in the installed Emacs distribution. See File-name conventions, if you don't know where that is.
  2. Run the install-info command, which is part of the Texinfo distribution, to update the main Info directory menu, like this:
               install-info --info-dir=dir-path dir-path/file
    

    where dir-path is the full path to the directory where you copied the produced Info file(s), and file is the name of the Info file you produced and want to install.

    If you don't have the install-info command installed, you can edit the file info/dir in the installed Emacs distribution, and add a line for the top level node in the Info package that you are installing. Follow the examples already in this file. The format is:

              * Topic: (relative-pathname).  Short description of topic.
    

If you want to install Info files and you don't have the necessary privileges, you have several options:

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3.6 How do I print a Texinfo file?

You can't get nicely printed output from Info files; you must still have the original Texinfo source file for the manual you want to print.

Assuming you have TeX installed on your system, follow these steps:

  1. Make sure the first line of the Texinfo file looks like this:
              \input texinfo
    

    You may need to change ‘texinfo’ to the full pathname of the texinfo.tex file, which comes with Emacs as doc/misc/texinfo.tex (or copy or link it into the current directory).

  2. Type texi2dvi texinfo-source, where texinfo-source is the name of the Texinfo source file for which you want to produce a printed copy. The ‘texi2dvi’ script is part of the GNU Texinfo distribution.

    Alternatively, ‘texi2pdf’ produces PDF files.

  3. Print the DVI file texinfo-source.dvi in the normal way for printing DVI files at your site. For example, if you have a PostScript printer, run the dvips program to print the DVI file on that printer.

To get more general instructions, retrieve the latest Texinfo package (see Installing Texinfo documentation).

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3.7 Can I view Info files without using Emacs?

Yes. Here are some alternative programs:

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3.8 What informational files are available for Emacs?

This isn't a frequently asked question, but it should be! A variety of informational files about Emacs and relevant aspects of the GNU project are available for you to read.

The following files (and others) are available in the etc directory of the Emacs distribution (see File-name conventions, if you're not sure where that is). Many of these files are available via the Emacs ‘Help’ menu, or by typing C-h ? (M-x help-for-help).

COPYING
GNU General Public License
DISTRIB
Emacs Availability Information
GNU
The GNU Manifesto
INTERVIEW
Richard Stallman discusses his public-domain UNIX-compatible software system with BYTE editors
MACHINES
Status of Emacs on Various Machines and Systems
MAILINGLISTS
GNU Project Electronic Mailing Lists
NEWS
Emacs news, a history of recent user-visible changes

More GNU information, including back issues of the GNU's Bulletin, are at

http://www.gnu.org/bulletins/bulletins.html and

http://www.cs.pdx.edu/~trent/gnu/gnu.html

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3.9 Where can I get help in installing Emacs?

See Installing Emacs, for some basic installation hints, and see Problems building Emacs, if you have problems with the installation.

The GNU Service directory lists companies and individuals willing to sell you help in installing or using Emacs and other GNU software.

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3.10 Where can I get the latest version of this FAQ?

The Emacs FAQ is distributed with Emacs in Info format. You can read it by selecting the ‘Emacs FAQ’ option from the ‘Help’ menu of the Emacs menu bar at the top of any Emacs frame, or by typing C-h C-f (M-x view-emacs-FAQ). The very latest version is available in the Emacs development repository (see Latest version of Emacs).

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4 Status of Emacs

This chapter gives you basic information about Emacs, including the status of its latest version.

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4.1 Where does the name “Emacs” come from?

Emacs originally was an acronym for Editor MACroS. RMS says he “picked the name Emacs because <E> was not in use as an abbreviation on ITS at the time.” The first Emacs was a set of macros written in 1976 at MIT by RMS for the editor TECO (Text Editor and COrrector, originally Tape Editor and COrrector) under ITS (the Incompatible Timesharing System) on a PDP-10. RMS had already extended TECO with a “real-time” full-screen mode with reprogrammable keys. Emacs was started by Guy Steele as a project to unify the many divergent TECO command sets and key bindings at MIT, and completed by RMS.

Many people have said that TECO code looks a lot like line noise; you can read more at news:alt.lang.teco. Someone has written a TECO implementation in Emacs Lisp (to find it, see Packages that do not come with Emacs); it would be an interesting project to run the original TECO Emacs inside of Emacs.

For some not-so-serious alternative reasons for Emacs to have that name, check out the file etc/JOKES (see File-name conventions).

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4.2 What is the latest version of Emacs?

Emacs 24.3 is the current version as of this writing. A version number with two components (e.g., ‘22.1’) indicates a released version; three components indicate a development version (e.g., ‘23.0.50’ is what will eventually become ‘23.1’).

Emacs is under active development, hosted at Savannah. The source code can be retrieved anonymously following the instructions. The repository is GNU Bazaar.

Because Emacs undergoes many changes before a release, the version number of a development version is not especially meaningful. It is better to refer to the date on which the sources were retrieved from the development repository. The development version is usually quite robust for every-day use, but if stability is more important to you than the latest features, you may want to stick to the releases.

The following sections list some of the major new features in the last few Emacs releases. For full details of the changes in any version of Emacs, type C-h C-n (M-x view-emacs-news). As of Emacs 22, you can give this command a prefix argument to read about which features were new in older versions.

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4.3 What is different about Emacs 24?

As always, consult the NEWS file for more information.

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4.4 What is different about Emacs 23?

Other changes include: support for serial port access; D-Bus bindings; a new Visual Line mode for line-motion; improved completion; a new mode (‘DocView’) for viewing of PDF, PostScript, and DVI documents; nXML mode (for editing XML documents) is included; VC has been updated for newer version control systems; etc.

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4.5 What is different about Emacs 22?

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4.6 What is different about Emacs 21?

Emacs 21 features a thorough rewrite of the display engine. The new display engine supports variable-size fonts, images, and can play sounds on platforms which support that. As a result, the visual appearance of Emacs, when it runs on a windowed display, is much more reminiscent of modern GUI programs, and includes 3D widgets (used for the mode line and the scroll bars), a configurable and extensible toolbar, tooltips (a.k.a. balloon help), and other niceties.

In addition, Emacs 21 supports faces on text-only terminals. This means that you can now have colors when you run Emacs on a GNU/Linux console and on xterm with emacs -nw.

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4.7 What is different about Emacs 20?

The differences between Emacs versions 18 and 19 were rather dramatic; the introduction of frames, faces, and colors on windowing systems was obvious to even the most casual user.

There are differences between Emacs versions 19 and 20 as well, but many are more subtle or harder to find. Among the changes are the inclusion of MULE code for languages that use non-Latin characters and for mixing several languages in the same document; the “Customize” facility for modifying variables without having to use Lisp; and automatic conversion of files from Macintosh, Microsoft, and Unix platforms.

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5 Common requests

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5.1 How do I set up a .emacs file properly?

See Init File.

In general, new Emacs users should not be provided with .emacs files, because this can cause confusing non-standard behavior. Then they send questions to help-gnu-emacs@gnu.org asking why Emacs isn't behaving as documented.

Emacs includes the Customize facility (see Using Customize). This allows users who are unfamiliar with Emacs Lisp to modify their .emacs files in a relatively straightforward way, using menus rather than Lisp code.

While Customize might indeed make it easier to configure Emacs, consider taking a bit of time to learn Emacs Lisp and modifying your .emacs directly. Simple configuration options are described rather completely in Init File, for users interested in performing frequently requested, basic tasks.

Sometimes users are unsure as to where their .emacs file should be found. Visiting the file as ~/.emacs from Emacs will find the correct file.

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5.2 How do I start using Customize?

The main Customize entry point is M-x customize <RET>. This command takes you to a buffer listing all the available Customize groups. From there, you can access all customizable options and faces, change their values, and save your changes to your init file. See Easy Customization.

If you know the name of the group in advance (e.g., “shell”), use M-x customize-group <RET>.

If you wish to customize a single option, use M-x customize-option <RET>. This command prompts you for the name of the option to customize, with completion.

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5.3 How do I get colors and syntax highlighting on a TTY?

In Emacs 21.1 and later, colors and faces are supported in non-windowed mode, i.e., on Unix and GNU/Linux text-only terminals and consoles, and when invoked as ‘emacs -nw’ on X, and MS-Windows. (Colors and faces were supported in the MS-DOS port since Emacs 19.29.) Emacs automatically detects color support at startup and uses it if available. If you think that your terminal supports colors, but Emacs won't use them, check the termcap entry for your display type for color-related capabilities.

The command M-x list-colors-display pops up a window which exhibits all the colors Emacs knows about on the current display.

Syntax highlighting is on by default since version 22.1.

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5.4 How do I debug a .emacs file?

Start Emacs with the ‘-debug-init’ command-line option. This enables the Emacs Lisp debugger before evaluating your .emacs file, and places you in the debugger if something goes wrong. The top line in the trace-back buffer will be the error message, and the second or third line of that buffer will display the Lisp code from your .emacs file that caused the problem.

You can also evaluate an individual function or argument to a function in your .emacs file by moving the cursor to the end of the function or argument and typing C-x C-e (M-x eval-last-sexp).

Use C-h v (M-x describe-variable) to check the value of variables which you are trying to set or use.

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5.5 How do I make Emacs display the current line (or column) number?

By default, Emacs displays the current line number of the point in the mode line. You can toggle this feature off or on with the command M-x line-number-mode, or by setting the variable line-number-mode. Note that Emacs will not display the line number if the buffer's size in bytes is larger than the value of the variable line-number-display-limit.

You can similarly display the current column with M-x column-number-mode, or by putting the form

     (setq column-number-mode t)

in your .emacs file. This feature is off by default.

The "%c" format specifier in the variable mode-line-format will insert the current column's value into the mode line. See the documentation for mode-line-format (using C-h v mode-line-format <RET>) for more information on how to set and use this variable.

The ‘linum’ package (distributed with Emacs since version 23.1) displays line numbers in the left margin, like the “set number” capability of vi. The packages ‘setnu’ and ‘wb-line-number’ (not distributed with Emacs) also implement this feature.

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5.6 How can I modify the titlebar to contain the current file name?

The contents of an Emacs frame's titlebar is controlled by the variable frame-title-format, which has the same structure as the variable mode-line-format. (Use C-h v or M-x describe-variable to get information about one or both of these variables.)

By default, the titlebar for a frame does contain the name of the buffer currently being visited, except if there is a single frame. In such a case, the titlebar contains Emacs invocation name and the name of the machine at which Emacs was invoked. This is done by setting frame-title-format to the default value of

     (multiple-frames "%b" ("" invocation-name "@" system-name))

To modify the behavior such that frame titlebars contain the buffer's name regardless of the number of existing frames, include the following in your .emacs:

     (setq frame-title-format "%b")

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5.7 How do I turn on abbrevs by default just in mode mymode?

Abbrev mode expands abbreviations as you type them. To turn it on in a specific buffer, use M-x abbrev-mode. To turn it on in every buffer by default, put this in your .emacs file:

     (setq-default abbrev-mode t)

To turn it on in a specific mode, use:

     (add-hook 'mymode-mode-hook
               (lambda ()
                (setq abbrev-mode t)))

If your Emacs version is older then 22.1, you will also need to use:

     (condition-case ()
        (quietly-read-abbrev-file)
       (file-error nil))

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5.8 How do I make Emacs use a certain major mode for certain files?

If you want to use a certain mode foo for all files whose names end with the extension .bar, this will do it for you:

     (add-to-list 'auto-mode-alist '("\\.bar\\'" . foo-mode))

Alternatively, put this somewhere in the first line of any file you want to edit in the mode foo (in the second line, if the first line begins with ‘#!’):

     -*- foo -*-

The variable interpreter-mode-alist specifies which mode to use when loading an interpreted script (e.g., shell, python, etc.). Emacs determines which interpreter you're using by examining the first line of the script. Use C-h v (or M-x describe-variable) on interpreter-mode-alist to learn more.

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5.9 How can I highlight a region of text in Emacs?

You can cause the region to be highlighted when the mark is active by including

     (transient-mark-mode 1)

in your .emacs file. Since Emacs 23.1, this feature is on by default.

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5.10 How can I replace highlighted text with what I type?

Use delete-selection-mode, which you can start automatically by placing the following Lisp form in your .emacs file:

     (delete-selection-mode 1)

According to the documentation string for delete-selection-mode (which you can read using M-x describe-function <RET> delete-selection-mode <RET>):

When Delete Selection mode is enabled, Transient Mark mode is also enabled and typed text replaces the selection if the selection is active. Otherwise, typed text is just inserted at point regardless of any selection.

This mode also allows you to delete (not kill) the highlighted region by pressing <DEL>.

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5.11 How do I control Emacs's case-sensitivity when searching/replacing?

The value of the variable case-fold-search determines whether searches are case sensitive:

     (setq case-fold-search nil) ; make searches case sensitive
     (setq case-fold-search t)   ; make searches case insensitive

Similarly, for replacing, the variable case-replace determines whether replacements preserve case.

You can also toggle case sensitivity at will in isearch with M-c.

To change the case sensitivity just for one major mode, use the major mode's hook. For example:

     (add-hook 'foo-mode-hook
               (lambda ()
                (setq case-fold-search nil)))

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5.12 How do I search for, delete, or replace unprintable (eight-bit or control) characters?

To search for a single character that appears in the buffer as, for example, ‘\237’, you can type C-s C-q 2 3 7. Searching for all unprintable characters is best done with a regular expression (regexp) search. The easiest regexp to use for the unprintable chars is the complement of the regexp for the printable chars.

To type these special characters in an interactive argument to isearch-forward-regexp or re-search-forward, you need to use C-q. (‘\t’, ‘\n’, ‘\r’, and ‘\f’ stand respectively for <TAB>, <LFD>, <RET>, and C-l.) So, to search for unprintable characters using re-search-forward:

M-x re-search-forward <RET> [^ <TAB> C-q <LFD> C-q <RET> C-q C-l <SPC> -~] <RET>

Using isearch-forward-regexp:

C-M-s [^ <TAB> <LFD> C-q <RET> C-q C-l <SPC> -~]

To delete all unprintable characters, simply use replace-regexp:

M-x replace-regexp <RET> [^ <TAB> C-q <LFD> C-q <RET> C-q C-l <SPC> -~] <RET> <RET>

Replacing is similar to the above. To replace all unprintable characters with a colon, use:

M-x replace-regexp <RET> [^ <TAB> C-q <LFD> C-q <RET> C-q C-l <SPC> -~] <RET> : <RET>

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5.13 How do I input a newline character in isearch or query-replace?

Use C-q C-j. For more information, see Special Input for Incremental Search.

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5.14 How do I copy text from the kill ring into the search string?

Use M-y. See Isearch Yank.

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5.15 How do I make Emacs wrap words for me?

Use auto-fill-mode, activated by typing M-x auto-fill-mode. The default maximum line width is 70, determined by the variable fill-column. To learn how to turn this on automatically, see Turning on auto-fill by default.

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5.16 How do I turn on auto-fill-mode by default?

To turn on auto-fill-mode just once for one buffer, use M-x auto-fill-mode.

To turn it on for every buffer in a certain mode, you must use the hook for that mode. For example, to turn on auto-fill mode for all text buffers, including the following in your .emacs file:

     (add-hook 'text-mode-hook 'turn-on-auto-fill)

If you want auto-fill mode on in all major modes, do this:

     (setq-default auto-fill-function 'do-auto-fill)

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5.17 How do I change load-path?

In general, you should only add to the load-path. You can add directory /dir/subdir to the load path like this:

     (add-to-list 'load-path "/dir/subdir/")

To do this relative to your home directory:

     (add-to-list 'load-path "~/mysubdir/")

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5.18 How do I use an already running Emacs from another window?

emacsclient, which comes with Emacs, is for editing a file using an already running Emacs rather than starting up a new Emacs. It does this by sending a request to the already running Emacs, which must be expecting the request.

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5.19 How do I make Emacs recognize my compiler's funny error messages?

Customize the compilation-error-regexp-alist variable.

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5.20 How do I change the indentation for switch?

Many people want to indent their switch statements like this:

     f()
     {
       switch(x) {
         case A:
           x1;
           break;
         case B:
           x2;
           break;
         default:
           x3;
       }
     }

To achieve this, add the following line to your .emacs:

     (c-set-offset 'case-label '+)

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5.21 How to customize indentation in C, C++, and Java buffers?

The Emacs cc-mode features an interactive procedure for customizing the indentation style, which is fully explained in the CC Mode manual that is part of the Emacs distribution, see Customization Indentation. Here's a short summary of the procedure:

  1. Go to the beginning of the first line where you don't like the indentation and type C-c C-o. Emacs will prompt you for the syntactic symbol; type <RET> to accept the default it suggests.
  2. Emacs now prompts for the offset of this syntactic symbol, showing the default (the current definition) inside parentheses. You can choose one of these:
    0
    No extra indentation.
    +
    Indent one basic offset.
    -
    Outdent one basic offset.
    ++
    Indent two basic offsets
    --
    Outdent two basic offsets.
    *
    Indent half basic offset.
    /
    Outdent half basic offset.
  3. After choosing one of these symbols, type C-c C-q to reindent the line or the block according to what you just specified.
  4. If you don't like the result, go back to step 1. Otherwise, add the following line to your .emacs:
              (c-set-offset 'syntactic-symbol offset)
    

    where syntactic-symbol is the name Emacs shows in the minibuffer when you type C-c C-o at the beginning of the line, and offset is one of the indentation symbols listed above (+, /, 0, etc.) that you've chosen during the interactive procedure.

  5. Go to the next line whose indentation is not to your liking and repeat the process there.

It is recommended to put all the resulting (c-set-offset ...) customizations inside a C mode hook, like this:

     (defun my-c-mode-hook ()
       (c-set-offset ...)
       (c-set-offset ...))
     (add-hook 'c-mode-hook 'my-c-mode-hook)

Using c-mode-hook avoids the need to put a (require 'cc-mode) into your .emacs file, because c-set-offset might be unavailable when cc-mode is not loaded.

Note that c-mode-hook runs for C source files only; use c++-mode-hook for C++ sources, java-mode-hook for Java sources, etc. If you want the same customizations to be in effect in all languages supported by cc-mode, use c-mode-common-hook.

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5.22 How can I make Emacs automatically scroll horizontally?

In Emacs 21 and later, this is on by default: if the variable truncate-lines is non-nil in the current buffer, Emacs automatically scrolls the display horizontally when point moves off the left or right edge of the window.

Note that this is overridden by the variable truncate-partial-width-windows if that variable is non-nil and the current buffer is not full-frame width.

In Emacs 20, use hscroll-mode.

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5.23 How do I make Emacs “typeover” or “overwrite” instead of inserting?

M-x overwrite-mode (a minor mode). This toggles overwrite-mode on and off, so exiting from overwrite-mode is as easy as another M-x overwrite-mode.

On some systems, <Insert> toggles overwrite-mode on and off.

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5.24 How do I stop Emacs from beeping on a terminal?

Martin R. Frank writes:

Tell Emacs to use the visible bell instead of the audible bell, and set the visible bell to nothing.

That is, put the following in your TERMCAP environment variable (assuming you have one):

     ... :vb=: ...

And evaluate the following Lisp form:

     (setq visible-bell t)

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5.25 How do I turn down the bell volume in Emacs running under X?

On X Window system, you can adjust the bell volume and duration for all programs with the shell command xset.

Invoking xset without any arguments produces some basic information, including the following:

     usage:  xset [-display host:dpy] option ...
       To turn bell off:
           -b                b off               b 0
       To set bell volume, pitch and duration:
            b [vol [pitch [dur]]]          b on

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5.26 How do I tell Emacs to automatically indent a new line to the indentation of the previous line?

Such behavior is automatic (in Text mode) in Emacs 20 and later. From the etc/NEWS file for Emacs 20.2:

     ** In Text mode, now only blank lines separate paragraphs.  This makes
     it possible to get the full benefit of Adaptive Fill mode in Text mode,
     and other modes derived from it (such as Mail mode).  <TAB> in Text
     mode now runs the command indent-relative; this makes a practical
     difference only when you use indented paragraphs.
     
     If you want spaces at the beginning of a line to start a paragraph, use
     the new mode, Paragraph Indent Text mode.

If you have auto-fill-mode turned on (see Turning on auto-fill by default), you can tell Emacs to prefix every line with a certain character sequence, the fill prefix. Type the prefix at the beginning of a line, position point after it, and then type C-x . (set-fill-prefix) to set the fill prefix. Thereafter, auto-filling will automatically put the fill prefix at the beginning of new lines, and M-q (fill-paragraph) will maintain any fill prefix when refilling the paragraph.

If you have paragraphs with different levels of indentation, you will have to set the fill prefix to the correct value each time you move to a new paragraph. There are many packages available to deal with this (see Packages that do not come with Emacs). Look for “fill” and “indent” keywords for guidance.

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5.27 How do I show which parenthesis matches the one I'm looking at?

Call show-paren-mode in your .emacs file:

     (show-paren-mode 1)

You can also enable this mode by selecting the ‘Paren Match Highlighting’ option from the ‘Options’ menu of the Emacs menu bar at the top of any Emacs frame.

Alternatives to this mode include:

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5.28 In C mode, can I show just the lines that will be left after #ifdef commands are handled by the compiler?

M-x hide-ifdef-mode. (This is a minor mode.) You might also want to investigate cpp.el, which is distributed with Emacs.

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5.29 How do I repeat a command as many times as possible?

As of Emacs 20.3, there is indeed a repeat command (C-x z) that repeats the last command. If you preface it with a prefix argument, the prefix arg is applied to the command.

You can also type C-x <ESC> <ESC> (repeat-complex-command) to reinvoke commands that used the minibuffer to get arguments. In repeat-complex-command you can type M-p and M-n (and also up-arrow and down-arrow, if your keyboard has these keys) to scan through all the different complex commands you've typed.

To repeat a set of commands, use keyboard macros. Use C-x ( and C-x ) to make a keyboard macro that invokes the command and then type C-x e. See Keyboard Macros.

If you're really desperate for the . command in vi that redoes the last insertion/deletion, use VIPER, a vi emulation mode which comes with Emacs, and which appears to support it.

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5.30 What are the valid X resource settings (i.e., stuff in .Xdefaults)?

See X Resources.

You can also use a resource editor, such as editres (for X11R5 and onwards), to look at the resource names for the menu bar, assuming Emacs was compiled with the X toolkit.

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5.31 How do I execute (“evaluate”) a piece of Emacs Lisp code?

There are a number of ways to execute (evaluate, in Lisp lingo) an Emacs Lisp form:

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5.32 How do I change Emacs's idea of the <TAB> character's length?

Set the default value of the variable tab-width. For example, to set <TAB> stops every 10 characters, insert the following in your .emacs file:

     (setq-default tab-width 10)

Do not confuse variable tab-width with variable tab-stop-list. The former is used for the display of literal <TAB> characters. The latter controls what characters are inserted when you press the <TAB> character in certain modes.

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5.33 How do I insert <some text> at the beginning of every line?

To do this to an entire buffer, type M-< M-x replace-regexp <RET> ^ <RET> your text <RET>.

To do this to a region, use string-insert-rectangle. Set the mark (C-<SPC>) at the beginning of the first line you want to prefix, move the cursor to last line to be prefixed, and type M-x string-insert-rectangle <RET>. To do this for the whole buffer, type C-x h M-x string-insert-rectangle <RET>.

If you are trying to prefix a yanked mail message with ‘>’, you might want to set the variable mail-yank-prefix. In Message buffers, you can even use M-; to cite yanked messages (M-; runs the function comment-region, it is a general-purpose mechanism to comment regions) (see Changing the included text prefix).

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5.34 How do I make Emacs behave like this: when I go up or down, the cursor should stay in the same column even if the line is too short?

Use M-x picture-mode.

See also the variable track-eol and the command set-goal-column bound to C-x C-n (see Moving Point).

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5.35 How do I tell Emacs to iconify itself?

C-z iconifies Emacs when running under X and suspends Emacs otherwise. See Frame Commands.

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5.36 How do I use regexps (regular expressions) in Emacs?

See Regexp Backslash.

The or operator is ‘\|’, not ‘|’, and the grouping operators are ‘\(’ and ‘\)’. Also, the string syntax for a backslash is ‘\\’. To specify a regular expression like ‘xxx\(foo\|bar\)’ in a Lisp string, use ‘xxx\\(foo\\|bar\\)’.

Note the doubled backslashes!

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5.37 How do I perform a replace operation across more than one file?

Dired mode (M-x dired <RET>, or C-x d) supports the command dired-do-query-replace-regexp (Q), which allows users to replace regular expressions in multiple files.

You can use this command to perform search/replace operations on multiple files by following the following steps:

Another way to do the same thing is to use the “tags” feature of Emacs: it includes the command tags-query-replace which performs a query-replace across all the files mentioned in the TAGS file. See Tags Search.

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5.38 Where is the documentation for etags?

The etags man page should be in the same place as the emacs man page.

Quick command-line switch descriptions are also available. For example, ‘etags -H’.

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5.39 How do I disable backup files?

You probably don't want to do this, since backups are useful, especially when something goes wrong.

To avoid seeing backup files (and other “uninteresting” files) in Dired, load dired-x by adding the following to your .emacs file:

     (add-hook 'dired-load-hook
               (lambda ()
                (require 'dired-x)))

With dired-x loaded, M-o toggles omitting in each dired buffer. You can make omitting the default for new dired buffers by putting the following in your .emacs:

     (add-hook 'dired-mode-hook 'dired-omit-toggle)

If you're tired of seeing backup files whenever you do an ‘ls’ at the Unix shell, try GNU ls with the ‘-B’ option. GNU ls is part of the GNU Fileutils package, available from ‘ftp.gnu.org’ and its mirrors (see Current GNU distributions).

To disable or change the way backups are made, see Backup Names.

Beginning with Emacs 21.1, you can control where Emacs puts backup files by customizing the variable backup-directory-alist. This variable's value specifies that files whose names match specific patters should have their backups put in certain directories. A typical use is to add the element ("." . dir) to force Emacs to put all backup files in the directory dir.

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5.40 How do I disable auto-save-mode?

You probably don't want to do this, since auto-saving is useful, especially when Emacs or your computer crashes while you are editing a document.

Instead, you might want to change the variable auto-save-interval, which specifies how many keystrokes Emacs waits before auto-saving. Increasing this value forces Emacs to wait longer between auto-saves, which might annoy you less.

You might also want to look into Sebastian Kremer's auto-save package (see Packages that do not come with Emacs). This package also allows you to place all auto-save files in one directory, such as /tmp.

To disable or change how auto-save-mode works, see Auto Save.

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5.41 How can I go to a certain line given its number?

Are you sure you indeed need to go to a line by its number? Perhaps all you want is to display a line in your source file for which a compiler printed an error message? If so, compiling from within Emacs using the M-x compile and M-x recompile commands is a much more effective way of doing that. Emacs automatically intercepts the compile error messages, inserts them into a special buffer called *compilation*, and lets you visit the locus of each message in the source. Type C-x ` to step through the offending lines one by one (starting with Emacs 22, you can also use M-g M-p and M-g M-n to go to the previous and next matches directly). Click Mouse-2 or press <RET> on a message text in the *compilation* buffer to go to the line whose number is mentioned in that message.

But if you indeed need to go to a certain text line, type M-g M-g (which is the default binding of the goto-line function starting with Emacs 22). Emacs will prompt you for the number of the line and go to that line.

You can do this faster by invoking goto-line with a numeric argument that is the line's number. For example, C-u 286 M-g M-g will jump to line number 286 in the current buffer.

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5.42 How can I create or modify new pull-down menu options?

Each menu title (e.g., ‘File’, ‘Edit’, ‘Buffers’) represents a local or global keymap. Selecting a menu title with the mouse displays that keymap's non-nil contents in the form of a menu.

So to add a menu option to an existing menu, all you have to do is add a new definition to the appropriate keymap. Adding a ‘Forward Word’ item to the ‘Edit’ menu thus requires the following Lisp code:

     (define-key global-map
       [menu-bar edit forward]
       '("Forward word" . forward-word))

The first line adds the entry to the global keymap, which includes global menu bar entries. Replacing the reference to global-map with a local keymap would add this menu option only within a particular mode.

The second line describes the path from the menu-bar to the new entry. Placing this menu entry underneath the ‘File’ menu would mean changing the word edit in the second line to file.

The third line is a cons cell whose first element is the title that will be displayed, and whose second element is the function that will be called when that menu option is invoked.

To add a new menu, rather than a new option to an existing menu, we must define an entirely new keymap:

     (define-key global-map [menu-bar words]
       (cons "Words" (make-sparse-keymap "Words")))

The above code creates a new sparse keymap, gives it the name ‘Words’, and attaches it to the global menu bar. Adding the ‘Forward Word’ item to this new menu would thus require the following code:

     (define-key global-map
       [menu-bar words forward]
       '("Forward word" . forward-word))

Note that because of the way keymaps work, menu options are displayed with the more recently defined items at the top. Thus if you were to define menu options ‘foo’, ‘bar’, and ‘baz’ (in that order), the menu option ‘baz’ would appear at the top, and ‘foo’ would be at the bottom.

One way to avoid this problem is to use the function define-key-after, which works the same as define-key, but lets you modify where items appear. The following Lisp code would insert the ‘Forward Word’ item in the ‘Edit’ menu immediately following the ‘Undo’ item:

     (define-key-after
       (lookup-key global-map [menu-bar edit])
       [forward]
       '("Forward word" . forward-word)
       'undo)

Note how the second and third arguments to define-key-after are different from those of define-key, and that we have added a new (final) argument, the function after which our new key should be defined.

To move a menu option from one position to another, simply evaluate define-key-after with the appropriate final argument.

More detailed information—and more examples of how to create and modify menu options—are in the Emacs Lisp Reference Manual, under “Menu Keymaps.” (See Emacs Lisp documentation, for information on this manual.)

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5.43 How do I delete menus and menu options?

The simplest way to remove a menu is to set its keymap to ‘nil’. For example, to delete the ‘Words’ menu (see Modifying pull-down menus), use:

     (define-key global-map [menu-bar words] nil)

Similarly, removing a menu option requires redefining a keymap entry to nil. For example, to delete the ‘Forward word’ menu option from the ‘Edit’ menu (we added it in Modifying pull-down menus), use:

     (define-key global-map [menu-bar edit forward] nil)

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5.44 How do I turn on syntax highlighting?

font-lock-mode is the standard way to have Emacs perform syntax highlighting in the current buffer. It is enabled by default in Emacs 22.1 and later.

With font-lock-mode turned on, different types of text will appear in different colors. For instance, in a programming mode, variables will appear in one face, keywords in a second, and comments in a third.

To turn font-lock-mode off within an existing buffer, use M-x font-lock-mode <RET>.

In Emacs 21 and earlier versions, you could use the following code in your .emacs file to turn on font-lock-mode globally:

     (global-font-lock-mode 1)

Highlighting a buffer with font-lock-mode can take quite a while, and cause an annoying delay in display, so several features exist to work around this.

In Emacs 21 and later, turning on font-lock-mode automatically activates the new Just-In-Time fontification provided by jit-lock-mode. jit-lock-mode defers the fontification of portions of buffer until you actually need to see them, and can also fontify while Emacs is idle. This makes display of the visible portion of a buffer almost instantaneous. For details about customizing jit-lock-mode, type C-h f jit-lock-mode <RET>.

In versions of Emacs before 21, different levels of decoration are available, from slight to gaudy. More decoration means you need to wait more time for a buffer to be fontified (or a faster machine). To control how decorated your buffers should become, set the value of font-lock-maximum-decoration in your .emacs file, with a nil value indicating default (usually minimum) decoration, and a t value indicating the maximum decoration. For the gaudiest possible look, then, include the line

     (setq font-lock-maximum-decoration t)

in your .emacs file. You can also set this variable such that different modes are highlighted in a different ways; for more information, see the documentation for font-lock-maximum-decoration with C-h v (or M-x describe-variable <RET>).

Also see the documentation for the function font-lock-mode, available by typing C-h f font-lock-mode (M-x describe-function <RET> font-lock-mode <RET>).

To print buffers with the faces (i.e., colors and fonts) intact, use M-x ps-print-buffer-with-faces or M-x ps-print-region-with-faces. You will need a way to send text to a PostScript printer, or a PostScript interpreter such as Ghostscript; consult the documentation of the variables ps-printer-name, ps-lpr-command, and ps-lpr-switches for more details.

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5.45 How can I force Emacs to scroll only one line when I move past the bottom of the screen?

Customize the scroll-conservatively variable with M-x customize-variable <RET> scroll-conservatively <RET> and set it to a large value like, say, 10000. For an explanation of what this means, see Auto Scrolling.

Alternatively, use the following Lisp form in your .emacs:

     (setq scroll-conservatively most-positive-fixnum)

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5.46 How can I edit MS-DOS files using Emacs?

As of Emacs 20, detection and handling of MS-DOS (and Windows) files is performed transparently. You can open MS-DOS files on a Unix system, edit it, and save it without having to worry about the file format.

When editing an MS-DOS style file, the mode line will indicate that it is a DOS file. On Unix and GNU/Linux systems, and also on a Macintosh, the string ‘(DOS)’ will appear near the left edge of the mode line; on DOS and Windows, where the DOS end-of-line (EOL) format is the default, a backslash (‘\’) will appear in the mode line.

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5.47 How can I tell Emacs to fill paragraphs with a single space after each period?

Add the following line to your .emacs file:

     (setq sentence-end-double-space nil)

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5.48 Why these strange escape sequences from ls from the Shell mode?

In many systems, ls is aliased to ‘ls --color’, which prints using ANSI color escape sequences. Emacs version 21.1 and later includes the ansi-color package, which lets Shell mode recognize these escape sequences. In Emacs 23.2 and later, the package is enabled by default; in earlier versions you can enable it by typing M-x ansi-color-for-comint-mode in the Shell buffer, or by adding (add-hook 'shell-mode-hook 'ansi-color-for-comint-mode-on) to your init file.

In Emacs versions before 21.1, the ansi-color package is not included. In that case, you need to unalias ls for interactive shells running in Emacs; this can be done by checking the EMACS variable in the environment.

Previous: Escape sequences in shell output, Up: Common requests

5.49 How can I start Emacs in fullscreen mode on MS-Windows?

Use the function w32-send-sys-command. For example, you can put the following in your .emacs file:

     (add-hook 'term-setup-hook
               #'(lambda () (w32-send-sys-command ?\xF030)))

To avoid the slightly distracting visual effect of Emacs starting with its default frame size and then growing to fullscreen, you can add an ‘Emacs.Geometry’ entry to the Windows registry settings. See X Resources.

To compute the correct values for width and height, first maximize the Emacs frame and then evaluate (frame-height) and (frame-width) with M-:.

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6 Bugs and problems

The Emacs manual lists some common kinds of trouble users could get into, see Dealing with Emacs Trouble, so you might look there if the problem you encounter isn't described in this chapter. If you decide you've discovered a bug, see Reporting Bugs, for instructions how to do that.

The file etc/PROBLEMS in the Emacs distribution lists various known problems with building and using Emacs on specific platforms; type C-h C-p to read it.

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6.1 Does Emacs have problems with files larger than 8 megabytes?

Old versions (i.e., anything before 19.29) of Emacs had problems editing files larger than 8 megabytes. In versions 19.29 and later, the maximum buffer size is at least 2^27−1, or 134,217,727 bytes, or 132 MBytes. The maximum buffer size on 32-bit machines increased to 256 MBytes in Emacs 22, and again to 512 MBytes in Emacs 23.2.

Emacs compiled on a 64-bit machine can handle much larger buffers.

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6.2 How do I get rid of ‘^M’ or echoed commands in my shell buffer?

Try typing M-x shell-strip-ctrl-m <RET> while in shell-mode to make them go away. If that doesn't work, you have several options:

For tcsh, put this in your .cshrc (or .tcshrc) file:

     if ($?EMACS) then
         if ("$EMACS" =~ /*) then
             if ($?tcsh) unset edit
             stty nl
         endif
     endif

Or put this in your .emacs_tcsh or ~/.emacs.d/init_tcsh.sh file:

     unset edit
     stty nl

Alternatively, use csh in your shell buffers instead of tcsh. One way is:

     (setq explicit-shell-file-name "/bin/csh")

and another is to do this in your .cshrc (or .tcshrc) file:

     setenv ESHELL /bin/csh

(You must start Emacs over again with the environment variable properly set for this to take effect.)

You can also set the ESHELL environment variable in Emacs Lisp with the following Lisp form,

     (setenv "ESHELL" "/bin/csh")

The above solutions try to prevent the shell from producing the ‘^M’ characters in the first place. If this is not possible (e.g., if you use a Windows shell), you can get Emacs to remove these characters from the buffer by adding this to your .emacs init file:

     (add-hook 'comint-output-filter-functions 'shell-strip-ctrl-m)

On a related note: if your shell is echoing your input line in the shell buffer, you might want to customize the comint-process-echoes variable in your shell buffers, or try the following command in your shell start-up file:

     stty -icrnl -onlcr -echo susp ^Z

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6.3 Why do I get an error message when I try to run M-x shell?

This might happen because Emacs tries to look for the shell in a wrong place. If you know where your shell executable is, set the variable explicit-shell-file-name in your .emacs file to point to its full file name.

Some people have trouble with Shell Mode on MS-Windows because of intrusive antivirus software; disabling the resident antivirus program solves the problems in those cases.

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6.4 Where is the termcap/terminfo entry for terminal type ‘emacs’?

The termcap entry for terminal type ‘emacs’ is ordinarily put in the ‘TERMCAP’ environment variable of subshells. It may help in certain situations (e.g., using rlogin from shell buffer) to add an entry for ‘emacs’ to the system-wide termcap file. Here is a correct termcap entry for ‘emacs’:

     emacs:tc=unknown:

To make a terminfo entry for ‘emacs’, use tic or captoinfo. You need to generate /usr/lib/terminfo/e/emacs. It may work to simply copy /usr/lib/terminfo/d/dumb to /usr/lib/terminfo/e/emacs.

Having a termcap/terminfo entry will not enable the use of full screen programs in shell buffers. Use M-x terminal-emulator for that instead.

A workaround to the problem of missing termcap/terminfo entries is to change terminal type ‘emacs’ to type ‘dumb’ or ‘unknown’ in your shell start up file. csh users could put this in their .cshrc files:

     if ("$term" == emacs) set term=dumb

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6.5 Why does Emacs say ‘Error in init file’?

An error occurred while loading either your .emacs file or the system-wide file site-lisp/default.el. Emacs 21.1 and later pops the *Messages* buffer, and puts there some additional information about the error, to provide some hints for debugging.

For information on how to debug your .emacs file, see Debugging a customization file.

It may be the case that you need to load some package first, or use a hook that will be evaluated after the package is loaded. A common case of this is explained in Terminal setup code works after Emacs has begun.

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6.6 Why does Emacs ignore my X resources (my .Xdefaults file)?

As of version 19, Emacs searches for X resources in the files specified by the following environment variables:

This emulates the functionality provided by programs written using the Xt toolkit.

XFILESEARCHPATH and XUSERFILESEARCHPATH should be a list of file names separated by colons. XAPPLRESDIR should be a list of directory names separated by colons.

Emacs searches for X resources:

  1. specified on the command line, with the ‘-xrm RESOURCESTRING’ option,
  2. then in the value of the ‘XENVIRONMENT’ environment variable,
    • or if that is unset, in the file named ~/.Xdefaults-hostname if it exists (where hostname is the name of the machine Emacs is running on),
  3. then in the screen-specific and server-wide resource properties provided by the server,
    • or if those properties are unset, in the file named ~/.Xdefaults if it exists,
  4. then in the files listed in ‘XUSERFILESEARCHPATH’,
    • or in files named lang/Emacs in directories listed in ‘XAPPLRESDIR’ (where lang is the value of the LANG environment variable), if the ‘LANG’ environment variable is set,
    • or in files named Emacs in the directories listed in ‘XAPPLRESDIR
    • or in ~/lang/Emacs (if the LANG environment variable is set),
    • or in ~/Emacs,
  5. then in the files listed in XFILESEARCHPATH.

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6.7 Why don't my customizations of the frame parameters work?

This probably happens because you have set the frame parameters in the variable initial-frame-alist. That variable holds parameters used only for the first frame created when Emacs starts. To customize the parameters of all frames, change the variable default-frame-alist instead.

These two variables exist because many users customize the initial frame in a special way. For example, you could determine the position and size of the initial frame, but would like to control the geometry of the other frames by individually positioning each one of them.

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6.8 How do I edit a file with a ‘$’ in its name?

When entering a file name in the minibuffer, Emacs will attempt to expand a ‘$’ followed by a word as an environment variable. To suppress this behavior, type $$ instead.

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6.9 Why does shell mode lose track of the shell's current directory?

Emacs has no way of knowing when the shell actually changes its directory. This is an intrinsic limitation of Unix. So it tries to guess by recognizing ‘cd’ commands. If you type cd followed by a directory name with a variable reference (cd $HOME/bin) or with a shell metacharacter (cd ../lib*), Emacs will fail to correctly guess the shell's new current directory. A huge variety of fixes and enhancements to shell mode for this problem have been written to handle this problem (see Finding a package with particular functionality).

You can tell Emacs the shell's current directory with the command M-x dirs.

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6.10 Are there any security risks in Emacs?

Previous: Security risks with Emacs, Up: Bugs and problems

6.11 Dired says, ‘no file on this line’ when I try to do something.

Dired uses a regular expression to find the beginning of a file name. In a long Unix-style directory listing (‘ls -l’), the file name starts after the date. The regexp has thus been written to look for the date. By default, it should understand dates and times regardless of the language, but if your directory listing has an unusual format, Dired may get confused.

There are two approaches to solving this. The first one involves setting things up so that ‘ls -l’ outputs a more standard format. See your OS manual for more information.

The second approach involves changing the regular expression used by dired, directory-listing-before-filename-regexp.

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7 Compiling and installing Emacs

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7.1 How do I install Emacs?

This answer is meant for users of Unix and Unix-like systems. Users of other operating systems should see the series of questions beginning with Emacs for MS-DOS, which describe where to get non-Unix source and binaries, and how to install Emacs on those systems.

Most GNU/Linux distributions provide pre-built Emacs packages. If Emacs is not installed already, you can install it by running (as root) a command such as ‘yum install emacs’ (Red Hat and derivatives) or ‘apt-get install emacs’ (Debian and derivatives).

If you want to compile Emacs yourself, read the file INSTALL in the source distribution. In brief:

Previous: Installing Emacs, Up: Compiling and installing Emacs

7.2 What should I do if I have trouble building Emacs?

First look in the file etc/PROBLEMS (where you unpack the Emacs source) to see if there is already a solution for your problem. Next, look for other questions in this FAQ that have to do with Emacs installation and compilation problems.

If you'd like to have someone look at your problem and help solve it, see Help installing Emacs.

If you cannot find a solution in the documentation, please report the problem (see Reporting bugs).

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8 Finding Emacs and related packages

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8.1 Where can I get Emacs on the net?

Information on downloading Emacs is available at the Emacs home-page.

See Installing Emacs, for information on how to obtain and build the latest version of Emacs, and see Current GNU distributions, for a list of archive sites that make GNU software available.

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8.2 How do I find a Emacs Lisp package that does XXX?

First of all, you should check to make sure that the package isn't already available. For example, typing M-x apropos <RET> wordstar <RET> lists all functions and variables containing the string ‘wordstar’.

It is also possible that the package is on your system, but has not been loaded. To see which packages are available for loading, look through your computer's lisp directory (see File-name conventions). The Lisp source to most packages contains a short description of how they should be loaded, invoked, and configured—so before you use or modify a Lisp package, see if the author has provided any hints in the source code.

The command C-h p (finder-by-keyword) allows you to browse the constituent Emacs packages.

For advice on how to find extra packages that are not part of Emacs, see Packages that do not come with Emacs.

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8.3 Where can I get Emacs Lisp packages that don't come with Emacs?

Your first port of call should be the M-x list-packages command. This connects to the GNU ELPA (“Emacs Lisp Package Archive”) server and fetches the list of additional packages that it offers. These are GNU packages that are available for use with Emacs, but are distributed separately. Select a package to get more details about the features that it offers, and then if you wish, Emacs can download and automatically install it for you.

The Emacs Lisp List (ELL), maintained by Stephen Eglen, aims to provide one compact list with links to all of the current Emacs Lisp files on the Internet. The ELL can be browsed over the web, or from Emacs with the ell package.

Many authors post their packages to the Emacs sources newsgroup. You can search the archives of this group with Google, or Gmane, for example.

Several packages are stored in the Lisp area of the Emacs Wiki.

Read the file etc/MORE.STUFF for more information about external packages.

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8.4 Spell-checkers

Various spell-checkers are compatible with Emacs, including:

GNU Aspell
http://aspell.net/
Ispell
http://fmg-www.cs.ucla.edu/geoff/ispell.html
Hunspell
http://hunspell.sourceforge.net/

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8.5 Where can I get other up-to-date GNU stuff?

The most up-to-date official GNU software is normally kept at

ftp://ftp.gnu.org/pub/gnu

A list of sites mirroring ‘ftp.gnu.org’ can be found at

http://www.gnu.org/order/ftp.html

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8.6 What is the difference between Emacs and XEmacs (formerly Lucid Emacs)?

XEmacs is a branch version of Emacs. It was first called Lucid Emacs, and was initially derived from a prerelease version of Emacs 19. In this FAQ, we use the name “Emacs” only for the official version.

Emacs and XEmacs each come with Lisp packages that are lacking in the other. The two versions have some significant differences at the Lisp programming level. Their current features are roughly comparable, though the support for some operating systems, character sets and specific packages might be quite different.

Some XEmacs code has been contributed to Emacs, and we would like to use other parts, but the earlier XEmacs maintainers did not always keep track of the authors of contributed code, which makes it impossible for the FSF to get copyright papers signed for that code. (The FSF requires these papers for all the code included in the Emacs release, aside from generic C support packages that retain their separate identity and are not integrated into the code of Emacs proper.)

If you want to talk about these two versions and distinguish them, please call them “Emacs” and “XEmacs.” To contrast “XEmacs” with “GNU Emacs” would be misleading, since XEmacs too has its origin in the work of the GNU Project. Terms such as “Emacsen” and “(X)Emacs” are not wrong, but they are not very clear, so it is better to write “Emacs and XEmacs.”

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8.7 I don't have enough disk space to install Emacs

GNU Zile is a lightweight Emacs clone. Zile is short for ‘Zile Is Lossy Emacs’. It has all of Emacs's basic editing features. The Zile binary typically has a size of about 130 kbytes, so this can be useful if you are in an extremely space-restricted environment. More information is available from

http://www.gnu.org/software/zile/

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8.8 Where can I get Emacs for MS-DOS?

To build Emacs from source for MS-DOS, see the instructions in the file msdos/INSTALL in the distribution. The DOS port builds and runs on plain DOS, and also on all versions of MS-Windows from version 3.X onwards, including Windows XP and Vista.

The file etc/PROBLEMS contains some additional information regarding Emacs under MS-DOS.

A pre-built binary distribution of the old Emacs 20 is available, as described at

ftp://ftp.delorie.com/pub/djgpp/current/v2gnu/emacs.README

For a list of other MS-DOS implementations of Emacs (and Emacs look-alikes), consult the list of “Emacs implementations and literature,” available at

http://www.finseth.com/emacs.html

Note that while many of these programs look similar to Emacs, they often lack certain features, such as the Emacs Lisp extension language.

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8.9 Where can I get Emacs for Microsoft Windows?

There is a separate FAQ for Emacs on MS-Windows. For MS-DOS, see Emacs for MS-DOS.

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8.10 Where can I get Emacs for GNUstep?

Beginning with version 23.1, Emacs supports GNUstep natively. See the file nextstep/INSTALL in the distribution.

Previous: Emacs for GNUstep, Up: Finding Emacs and related packages

8.11 Where can I get Emacs for Mac OS X?

Beginning with version 22.1, Emacs supports Mac OS X natively. See the file nextstep/INSTALL in the distribution.

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9 Key bindings

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9.1 How do I bind keys (including function keys) to commands?

Keys can be bound to commands either interactively or in your .emacs file. To interactively bind keys for all modes, type M-x global-set-key <RET> key cmd <RET>.

To bind a key just in the current major mode, type M-x local-set-key <RET> key cmd <RET>.

See Key Bindings.

To make the process of binding keys interactively easier, use the following “trick”: First bind the key interactively, then immediately type C-x <ESC> <ESC> C-a C-k C-g. Now, the command needed to bind the key is in the kill ring, and can be yanked into your .emacs file. If the key binding is global, no changes to the command are required. For example,

     (global-set-key (quote [f1]) (quote help-for-help))

can be placed directly into the .emacs file. If the key binding is local, the command is used in conjunction with the ‘add-hook’ function. For example, in TeX mode, a local binding might be

     (add-hook 'tex-mode-hook
       (lambda ()
        (local-set-key (quote [f1]) (quote help-for-help))))

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9.2 Why does Emacs say ‘Key sequence XXX uses invalid prefix characters’?

Usually, one of two things has happened. In one case, the control character in the key sequence has been misspecified (e.g., ‘C-f’ used instead of ‘\C-f’ within a Lisp expression). In the other case, a prefix key in the keystroke sequence you were trying to bind was already bound as a complete key. Historically, the ‘ESC [’ prefix was usually the problem, in which case you should evaluate either of these forms before attempting to bind the key sequence:

     (global-unset-key [?\e ?[])  ;;  or
     (global-unset-key "\e[")

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9.3 Why doesn't this [terminal or window-system setup] code work in my .emacs file, but it works just fine after Emacs starts up?

During startup, Emacs initializes itself according to a given code/file order. If some of the code executed in your .emacs file needs to be postponed until the initial terminal or window-system setup code has been executed but is not, then you will experience this problem (this code/file execution order is not enforced after startup).

To postpone the execution of Emacs Lisp code until after terminal or window-system setup, treat the code as a lambda list and set the value of either the term-setup-hook or window-setup-hook variable to this lambda function. For example,

     (add-hook 'term-setup-hook
               (lambda ()
                (when (string-match "\\`vt220" (or (getenv "TERM") ""))
                  ;; Make vt220's "Do" key behave like M-x:
                  (global-set-key [do] 'execute-extended-command))))

For information on what Emacs does every time it is started, see the lisp/startup.el file.

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9.4 How do I tell what characters or symbols my function or arrow keys emit?

Type C-h c then the function or arrow keys. The command will return either a function key symbol or character sequence (see the Emacs documentation for an explanation). This works for other keys as well.

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9.5 How do I set the X key “translations” for Emacs?

Emacs is not written using the Xt library by default, so there are no “translations” to be set. (We aren't sure how to set such translations if you do build Emacs with Xt; please let us know if you've done this!)

The only way to affect the behavior of keys within Emacs is through xmodmap (outside Emacs) or define-key (inside Emacs). The define-key command should be used in conjunction with the function-key-map map. For instance,

     (define-key function-key-map [M-<TAB>] [?\M-\t])

defines the M-<TAB> key sequence.

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9.6 Why does the <Backspace> key invoke help?

The <Backspace> key (on most keyboards) generates ASCII code 8. C-h sends the same code. In Emacs by default C-h invokes help-command. This is intended to be easy to remember since the first letter of ‘help’ is ‘h’. The easiest solution to this problem is to use C-h (and <Backspace>) for help and <DEL> (the <Delete> key) for deleting the previous character.

For many people this solution may be problematic:

When Emacs 21 or later runs on a windowed display, it binds the <Delete> key to a command which deletes the character at point, to make Emacs more consistent with keyboard operation on these systems.

For more information about troubleshooting this problem, see If <DEL> Fails to Delete.

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9.7 How do I swap two keys?

You can swap two keys (or key sequences) by using the keyboard-translate function. For example, to turn C-h into <DEL> and <DEL> to C-h, use

     (keyboard-translate ?\C-h ?\C-?)  ; translate `C-h' to DEL
     (keyboard-translate ?\C-? ?\C-h)  ; translate DEL to `C-h'.

The first key sequence of the pair after the function identifies what is produced by the keyboard; the second, what is matched for in the keymaps.

However, in the specific case of C-h and <DEL>, you should toggle normal-erase-is-backspace-mode instead of calling keyboard-translate. See DEL Does Not Delete.

Keyboard translations are not the same as key bindings in keymaps. Emacs contains numerous keymaps that apply in different situations, but there is only one set of keyboard translations, and it applies to every character that Emacs reads from the terminal. Keyboard translations take place at the lowest level of input processing; the keys that are looked up in keymaps contain the characters that result from keyboard translation.

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9.8 How do I produce C-XXX with my keyboard?

On terminals (but not under X), some common “aliases” are:

C-2 or C-<SPC>
C-@
C-6
C-^
C-7 or C-S--
C-_
C-4
C-\
C-5
C-]
C-/
C-?

Often other aliases exist; use the C-h c command and try <CTRL> with all of the digits on your keyboard to see what gets generated. You can also try the C-h w command if you know the name of the command.

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9.9 What if I don't have a <Meta> key?

On many keyboards, the <Alt> key acts as <Meta>, so try it.

Instead of typing M-a, you can type <ESC> a. In fact, Emacs converts M-a internally into <ESC> a anyway (depending on the value of meta-prefix-char). Note that you press <Meta> and <a> together, but with <ESC>, you press <ESC>, release it, and then press <a>.

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9.10 What if I don't have an <Escape> key?

Type C-[ instead. This should send ASCII code 27 just like an Escape key would. C-3 may also work on some terminal (but not under X). For many terminals (notably DEC terminals) <F11> generates <ESC>. If not, the following form can be used to bind it:

     ;; F11 is the documented ESC replacement on DEC terminals.
     (define-key function-key-map [f11] [?\e])

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9.11 Can I make my <Compose Character> key behave like a <Meta> key?

On a dumb terminal such as a VT220, no. It is rumored that certain VT220 clones could have their <Compose> key configured this way. If you're using X, you might be able to do this with the xmodmap command.

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9.12 How do I bind a combination of modifier key and function key?

You can represent modified function keys in vector format by adding prefixes to the function key symbol. For example (from the Emacs documentation):

     (global-set-key [?\C-x right] 'forward-page)

where ‘?\C-x’ is the Lisp character constant for the character C-x.

You can use the modifier keys <Control>, <Meta>, <Hyper>, <Super>, <Alt>, and <Shift> with function keys. To represent these modifiers, prepend the strings ‘C-’, ‘M-’, ‘H-’, ‘s-’, ‘A-’, and ‘S-’ to the symbol name. Here is how to make H-M-RIGHT move forward a word:

     (global-set-key [H-M-right] 'forward-word)

See Binding keys to commands, for general key binding instructions.

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9.13 Why doesn't my <Meta> key work in an xterm window?

See Single-Byte Character Set Support.

If the advice in the Emacs manual fails, try all of these methods before asking for further help:

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9.14 Why doesn't my <ExtendChar> key work as a <Meta> key under HP-UX 8.0 and 9.x?

This is a result of an internationalization extension in X11R4 and the fact that HP is now using this extension. Emacs assumes that the XLookupString function returns the same result regardless of the <Meta> key state which is no longer necessarily true. Until Emacs is fixed, the temporary kludge is to run this command after each time the X server is started but preferably before any xterm clients are:

     xmodmap -e 'remove mod1 = Mode_switch'

This will disable the use of the extra keysyms systemwide, which may be undesirable if you actually intend to use them.

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9.15 Why doesn't SPC complete file names anymore?

Starting with Emacs 22.1, SPC no longer completes file names in the minibuffer, so that file names with embedded spaces could be typed without the need to quote the spaces.

You can get the old behavior by binding SPC to minibuffer-complete-word in the minibuffer, as follows:

     (define-key minibuffer-local-filename-completion-map (kbd "SPC")
       'minibuffer-complete-word)
     
     (define-key minibuffer-local-must-match-filename-map (kbd "SPC")
       'minibuffer-complete-word)

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10 Alternate character sets

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10.1 How do I make Emacs display 8-bit characters?

See Single-byte Character Set Support. On a Unix, when Emacs runs on a text-only terminal display or is invoked with ‘emacs -nw’, you typically need to use set-terminal-coding-system to tell Emacs what the terminal can display, even after setting the language environment; otherwise non-ASCII characters will display as ‘?’. On other operating systems, such as MS-DOS and MS-Windows, Emacs queries the OS about the character set supported by the display, and sets up the required terminal coding system automatically.

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10.2 How do I input eight-bit characters?

Various methods are available for input of eight-bit characters. See Single-byte Character Set Support. For more sophisticated methods, see Input Methods.

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10.3 Where is an Emacs that can handle Semitic (right-to-left) alphabets?

Emacs supports display and editing of bidirectional scripts, such as Arabic, Farsi, and Hebrew, since version 24.1. See bidirectional display.

Previous: Right-to-left alphabets, Up: Alternate character sets

10.4 How do I add fonts for use with Emacs?

First, download and install the BDF font files and any auxiliary packages they need. The GNU Intlfonts distribution can be found on the GNU Software Directory Web site.

Next, if you are on X Window system, issue the following two commands from the shell's prompt:

       xset +fp /usr/local/share/emacs/fonts
       xset fp rehash

(Modify the first command if you installed the fonts in a directory that is not /usr/local/share/emacs/fonts.) You also need to arrange for these two commands to run whenever you log in, e.g., by adding them to your window-system startup file, such as ~/.xsessionrc or ~/.gnomerc.

Now, add the following line to your ~/.emacs init file:

       (add-to-list 'bdf-directory-list "/usr/share/emacs/fonts/bdf")

(Again, modify the file name if you installed the fonts elsewhere.)

Finally, if you wish to use the installed fonts with ps-print, add the following line to your ~/.emacs:

       (setq ps-multibyte-buffer 'bdf-font-except-latin)

A few additional steps are necessary for MS-Windows; they are listed below.

First, make sure all the directories with BDF font files are mentioned in bdf-directory-list. On Unix and GNU/Linux systems, one normally runs make install to install the BDF fonts in the same directory. By contrast, Windows users typically don't run the Intlfonts installation command, but unpack the distribution in some directory, which leaves the BDF fonts in its subdirectories. For example, assume that you unpacked Intlfonts in C:/Intlfonts; then you should set bdf-directory-list as follows:

       (setq bdf-directory-list
         '("C:/Intlfonts/Asian"
           "C:/Intlfonts/Chinese" "C:/Intlfonts/Chinese.X"
           "C:/Intlfonts/Chinese.BIG" "C:/Intlfonts/Ethiopic"
           "C:/Intlfonts/European" "C:/Intlfonts/European.BIG"
           "C:/Intlfonts/Japanese" "C:/Intlfonts/Japanese.X"
           "C:/Intlfonts/Japanese.BIG" "C:/Intlfonts/Korean.X"
           "C:/Intlfonts/Misc"))

Next, you need to set up the variable w32-bdf-filename-alist to an alist of the BDF fonts and their corresponding file names. Assuming you have set bdf-directory-list to name all the directories with the BDF font files, the following Lisp snippet will set up w32-bdf-filename-alist:

       (setq w32-bdf-filename-alist
          (w32-find-bdf-fonts bdf-directory-list))

Now, create fontsets for the BDF fonts:

       (create-fontset-from-fontset-spec
        "-*-fixed-medium-r-normal-*-16-*-*-*-c-*-fontset-bdf,
        japanese-jisx0208:-*-*-medium-r-normal-*-16-*-*-*-c-*-jisx0208.1983-*,
        katakana-jisx0201:-*-*-medium-r-normal-*-16-*-*-*-c-*-jisx0201*-*,
        latin-jisx0201:-*-*-medium-r-normal-*-16-*-*-*-c-*-jisx0201*-*,
        japanese-jisx0208-1978:-*-*-medium-r-normal-*-16-*-*-*-c-*-jisx0208.1978-*,
        thai-tis620:-misc-fixed-medium-r-normal--16-160-72-72-m-80-tis620.2529-1,
        lao:-misc-fixed-medium-r-normal--16-160-72-72-m-80-MuleLao-1,
        tibetan-1-column:-TibMdXA-fixed-medium-r-normal--16-160-72-72-m-80-MuleTibetan-1,
        ethiopic:-Admas-Ethiomx16f-Medium-R-Normal--16-150-100-100-M-160-Ethiopic-Unicode,
        tibetan:-TibMdXA-fixed-medium-r-normal--16-160-72-72-m-160-MuleTibetan-0")

Many of the international bdf fonts from Intlfonts are type 0, and therefore need to be added to font-encoding-alist:

       (setq font-encoding-alist
             (append '(("MuleTibetan-0" (tibetan . 0))
                       ("GB2312"        (chinese-gb2312 . 0))
                       ("JISX0208"      (japanese-jisx0208 . 0))
                       ("JISX0212"      (japanese-jisx0212 . 0))
                       ("VISCII"        (vietnamese-viscii-lower . 0))
                       ("KSC5601"       (korean-ksc5601 . 0))
                       ("MuleArabic-0"  (arabic-digit . 0))
                       ("MuleArabic-1"  (arabic-1-column . 0))
                       ("MuleArabic-2"  (arabic-2-column . 0)))
                     font-encoding-alist))

You can now use the Emacs font menu to select the ‘bdf: 16-dot medium’ fontset, or you can select it by setting the default font in your ~/.emacs:

       (set-default-font "fontset-bdf")

Next: , Previous: Alternate character sets, Up: Top

11 Mail and news

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11.1 How do I change the included text prefix in mail/news followups?

If you read mail with Rmail, set the variable mail-yank-prefix. For Gnus, set message-yank-prefix. For VM, set vm-included-text-prefix. For mh-e, set mh-ins-buf-prefix.

For fancier control of citations, use Supercite (see the Supercite Manual).

To prevent Emacs from including various headers of the replied-to message, set the value of mail-yank-ignored-headers to an appropriate regexp.

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11.2 How do I save a copy of outgoing mail?

You can either mail yourself a copy by including a ‘BCC’ header in the mail message, or store a copy of the message directly to a file by including an ‘FCC’ header.

If you use standard mail, you can automatically create a ‘BCC’ to yourself by putting

     (setq mail-self-blind t)

in your .emacs file. You can automatically include an ‘FCC’ field by putting something like the following in your .emacs file:

     (setq mail-archive-file-name (expand-file-name "~/outgoing"))

The output file will be in Unix mail format.

If you use mh-e, add an ‘FCC’ or ‘BCC’ field to your components file.

It does not work to put ‘set record filename’ in the .mailrc file.

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11.3 Why doesn't Emacs expand my aliases when sending mail?

See The Emacs Manual.

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11.4 How can I sort the messages in my Rmail folder?

In Rmail, type C-c C-s C-h to get a list of sorting functions and their key bindings.

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11.5 Why does Rmail need to write to /var/spool/mail?

This is the behavior of the movemail program which Rmail uses. This indicates that movemail is configured to use lock files.

RMS writes:

Certain systems require lock files to interlock access to mail files. On these systems, movemail must write lock files, or you risk losing mail. You simply must arrange to let movemail write them.

Other systems use the flock system call to interlock access. On these systems, you should configure movemail to use flock.

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11.6 How can I force Rmail to reply to the sender of a message, but not the other recipients?

Ron Isaacson says: When you hit <r> to reply in Rmail, by default it CCs all of the original recipients (everyone on the original ‘To’ and ‘CC’ lists). With a prefix argument (i.e., typing C-u before <r>), it replies only to the sender. However, going through the whole C-u business every time you want to reply is a pain. This is the best fix I've been able to come up with:

     (defun rmail-reply-t ()
       "Reply only to the sender of the current message. (See rmail-reply.)"
       (interactive)
       (rmail-reply t))
     
     (add-hook 'rmail-mode-hook
       (lambda ()
         (define-key rmail-mode-map "r" 'rmail-reply-t)
         (define-key rmail-mode-map "R" 'rmail-reply)))

Next: , Previous: Replying to the sender of a message, Up: Mail and news

11.7 How do I make Emacs automatically start my mail/news reader?

To start Emacs in Gnus:

     emacs -f gnus

in Rmail:

     emacs -f rmail

A more convenient way to start with Gnus:

     alias gnus 'emacs -f gnus'
     gnus

It is probably unwise to automatically start your mail or news reader from your .emacs file. This would cause problems if you needed to run two copies of Emacs at the same time. Also, this would make it difficult for you to start Emacs quickly when you needed to.

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11.8 How do I read news under Emacs?

Use M-x gnus. For more information on Gnus, see the Gnus Manual, which includes the Gnus FAQ.

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11.9 Why doesn't Gnus work via NNTP?

There is a bug in NNTP version 1.5.10, such that when multiple requests are sent to the NNTP server, the server only handles the first one before blocking waiting for more input which never comes. NNTP version 1.5.11 claims to fix this.

You can work around the bug inside Emacs like this:

     (setq nntp-maximum-request 1)

You can find out what version of NNTP your news server is running by telnetting to the NNTP port (usually 119) on the news server machine (i.e., telnet server-machine 119). The server should give its version number in the welcome message. Type quit to get out.

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11.10 How do I make Gnus faster?

From the Gnus FAQ (see Reading news with Emacs):

If you have a slow machine, or are just really impatient, there are a few things you can do to make Gnus run faster.

Set gnus-check-new-newsgroups and gnus-check-bogus-newsgroups to nil to make startup faster.

Set gnus-show-threads, gnus-use-cross-reference and gnus-nov-is-evil to nil to make entering and exiting the summary buffer faster.

Previous: Making Gnus faster, Up: Mail and news

11.11 How do I catch up all newsgroups in Gnus?

In the *Newsgroup* buffer, type M-< C-x ( c y C-x ) M-0 C-x e

Leave off the initial M-< if you only want to catch up from point to the end of the *Newsgroup* buffer.

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Concept Index


Footnotes

[1] DOS and Windows terminals don't set bit 7 when the <Meta> key is pressed.