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1 \input texinfo @c -*- mode: texinfo; -*-
2 @c %**start of header
3 @setfilename ../../info/efaq
4 @settitle GNU Emacs FAQ
5 @documentencoding UTF-8
6 @c %**end of header
7
8 @include emacsver.texi
9
10 @c This file is maintained by Romain Francoise <rfrancoise@gnu.org>.
11 @c Feel free to install changes without prior permission (but I'd
12 @c appreciate a notice if you do).
13
14 @copying
15 Copyright @copyright{} 2001--2014 Free Software Foundation, Inc.@*
16 Copyright @copyright{} 1994, 1995, 1996, 1997, 1998, 1999, 2000
17 Reuven M. Lerner@*
18 Copyright @copyright{} 1992, 1993 Steven Byrnes@*
19 Copyright @copyright{} 1990, 1991, 1992 Joseph Brian Wells@*
20
21 @quotation
22 This list of frequently asked questions about GNU Emacs with answers
23 (``FAQ'') may be translated into other languages, transformed into other
24 formats (e.g., Texinfo, Info, WWW, WAIS), and updated with new information.
25
26 The same conditions apply to any derivative of the FAQ as apply to the FAQ
27 itself. Every copy of the FAQ must include this notice or an approved
28 translation, information on who is currently maintaining the FAQ and how to
29 contact them (including their e-mail address), and information on where the
30 latest version of the FAQ is archived (including FTP information).
31
32 The FAQ may be copied and redistributed under these conditions, except that
33 the FAQ may not be embedded in a larger literary work unless that work
34 itself allows free copying and redistribution.
35
36 [This version has been heavily edited since it was included in the Emacs
37 distribution.]
38 @end quotation
39 @end copying
40
41 @dircategory Emacs
42 @direntry
43 * Emacs FAQ: (efaq). Frequently Asked Questions about Emacs.
44 @end direntry
45
46 @c The @titlepage stuff only appears in the printed version
47 @titlepage
48 @sp 10
49 @center @titlefont{GNU Emacs FAQ}
50
51 @c The following two commands start the copyright page.
52 @page
53 @vskip 0pt plus 1filll
54 @insertcopying
55 @end titlepage
56
57 @contents
58
59 @node Top, FAQ notation, (dir), (dir)
60 @top The GNU Emacs FAQ
61
62 This is the GNU Emacs FAQ.
63
64 This FAQ is maintained as a part of GNU Emacs. If you find any errors,
65 or have any suggestions, please use @kbd{M-x report-emacs-bug} to report
66 them.
67
68 This is the version of the FAQ distributed with Emacs @value{EMACSVER}, and
69 mainly describes that version. Although there is some information on
70 older versions, details about very old releases (now only of historical
71 interest) have been removed. If you are interested in this, consult
72 either the version of the FAQ distributed with older versions of Emacs,
73 or the history of this document in the Emacs source repository.
74
75 Since Emacs releases are very stable, we recommend always running the
76 latest release.
77
78 This FAQ is not updated very frequently. When you have a question about
79 Emacs, the Emacs manual is often the best starting point.
80
81 @ifnottex
82 @insertcopying
83 @end ifnottex
84
85 @menu
86 * FAQ notation::
87 * General questions::
88 * Getting help::
89 * Status of Emacs::
90 * Common requests::
91 * Bugs and problems::
92 * Compiling and installing Emacs::
93 * Finding Emacs and related packages::
94 * Key bindings::
95 * Alternate character sets::
96 * Mail and news::
97 * Concept index::
98 @end menu
99
100 @c ------------------------------------------------------------
101 @node FAQ notation
102 @chapter FAQ notation
103 @cindex FAQ notation
104
105 This chapter describes notation used in the GNU Emacs FAQ, as well as in
106 the Emacs documentation. Consult this section if this is the first time
107 you are reading the FAQ, or if you are confused by notation or terms
108 used in the FAQ.
109
110 @menu
111 * Basic keys::
112 * Extended commands::
113 * Emacs manual::
114 * File-name conventions::
115 * Common acronyms::
116 @end menu
117
118 @node Basic keys
119 @section What do these mean: @kbd{C-h}, @kbd{C-M-a}, @key{RET}, @kbd{@key{ESC} a}, etc.?
120 @cindex Basic keys
121 @cindex Control key, notation for
122 @cindex @key{Meta} key, notation for
123 @cindex Control-Meta characters, notation for
124 @cindex @kbd{C-h}, definition of
125 @cindex @kbd{C-M-h}, definition of
126 @cindex @key{DEL}, definition of
127 @cindex @key{ESC}, definition of
128 @cindex @key{LFD}, definition of
129 @cindex @key{RET}, definition of
130 @cindex @key{SPC}, definition of
131 @cindex @key{TAB}, definition of
132 @cindex Notation for keys
133
134 @itemize @bullet
135
136 @item
137 @kbd{C-x}: press the @key{x} key while holding down the @key{Control} key
138
139 @item
140 @kbd{M-x}: press the @key{x} key while holding down the @key{Meta} key
141 (if your computer doesn't have a @key{Meta} key, @pxref{No Meta key})
142
143 @item
144 @kbd{M-C-x}: press the @key{x} key while holding down both @key{Control}
145 and @key{Meta}
146
147 @item
148 @kbd{C-M-x}: a synonym for the above
149
150 @item
151 @key{LFD}: Linefeed or Newline; same as @kbd{C-j}
152
153 @item
154 @key{RET}: @key{Return}, sometimes marked @key{Enter}; same as @kbd{C-m}
155
156 @item
157 @key{DEL}: @key{Delete}, usually @strong{not} the same as
158 @key{Backspace}; same as @kbd{C-?} (see @ref{Backspace invokes help}, if
159 deleting invokes Emacs help)
160
161 @item
162 @key{ESC}: Escape; same as @kbd{C-[}
163
164 @item
165 @key{TAB}: Tab; same as @kbd{C-i}
166
167 @item
168 @key{SPC}: Space bar
169
170 @end itemize
171
172 Key sequences longer than one key (and some single-key sequences) are
173 written inside quotes or on lines by themselves, like this:
174
175 @display
176 @kbd{M-x frobnicate-while-foo RET}
177 @end display
178
179 @noindent
180 Any real spaces in such a key sequence should be ignored; only @key{SPC}
181 really means press the space key.
182
183 The @acronym{ASCII} code sent by @kbd{C-x} (except for @kbd{C-?}) is the value
184 that would be sent by pressing just @key{x} minus 96 (or 64 for
185 upper-case @key{X}) and will be from 0 to 31. On Unix and GNU/Linux
186 terminals, the @acronym{ASCII} code sent by @kbd{M-x} is the sum of 128 and the
187 @acronym{ASCII} code that would be sent by pressing just @key{x}. Essentially,
188 @key{Control} turns off bits 5 and 6 and @key{Meta} turns on bit
189 7@footnote{
190 DOS and Windows terminals don't set bit 7 when the @key{Meta} key is
191 pressed.}.
192
193 @kbd{C-?} (aka @key{DEL}) is @acronym{ASCII} code 127. It is a misnomer to call
194 @kbd{C-?} a ``control'' key, since 127 has both bits 5 and 6 turned ON@.
195 Also, on very few keyboards does @kbd{C-?} generate @acronym{ASCII} code 127.
196 @c FIXME I cannot understand the previous sentence.
197
198 @xref{Keys,,, emacs, The GNU Emacs Manual}.
199
200 @node Extended commands
201 @section What does @file{M-x @var{command}} mean?
202 @cindex Extended commands
203 @cindex Commands, extended
204 @cindex M-x, meaning of
205
206 @kbd{M-x @var{command}} means type @kbd{M-x}, then type the name of the
207 command, then type @key{RET}. (@xref{Basic keys}, if you're not sure
208 what @kbd{M-x} and @key{RET} mean.)
209
210 @kbd{M-x} (by default) invokes the command
211 @code{execute-extended-command}. This command allows you to run any
212 Emacs command if you can remember the command's name. If you can't
213 remember the command's name, you can type @key{TAB} and @key{SPC} for
214 completion, @key{?} for a list of possibilities, and @kbd{M-p} and
215 @kbd{M-n} (or up-arrow and down-arrow) to see previous commands entered.
216 An Emacs @dfn{command} is an @dfn{interactive} Emacs function.
217
218 @cindex @key{Do} key
219 Your system administrator may have bound other key sequences to invoke
220 @code{execute-extended-command}. A function key labeled @kbd{Do} is a
221 good candidate for this, on keyboards that have such a key.
222
223 If you need to run non-interactive Emacs functions, see @ref{Evaluating
224 Emacs Lisp code}.
225
226 @node Emacs manual
227 @section How do I read topic XXX in the Emacs manual?
228 @cindex Emacs manual, reading topics in
229 @cindex Reading topics in the Emacs manual
230 @cindex Finding topics in the Emacs manual
231 @cindex Info, finding topics in
232
233 When we refer you to some @var{topic} in the Emacs manual, you can
234 read this manual node inside Emacs (assuming nothing is broken) by
235 typing @kbd{C-h i m emacs @key{RET} m @var{topic} @key{RET}}.
236
237 This invokes Info, the GNU hypertext documentation browser. If you don't
238 already know how to use Info, type @key{?} from within Info.
239
240 If we refer to @var{topic}:@var{subtopic}, type @kbd{C-h i m emacs
241 @key{RET} m @var{topic} @key{RET} m @var{subtopic} @key{RET}}.
242
243 If these commands don't work as expected, your system administrator may
244 not have installed the Info files, or may have installed them
245 improperly. In this case you should complain.
246
247 If you are reading this FAQ in Info, you can simply press @key{RET} on a
248 reference to follow it.
249
250 @xref{Getting a printed manual}, if you would like a paper copy of the
251 Emacs manual.
252
253 @node File-name conventions
254 @section What are @file{src/config.h}, @file{site-lisp/default.el}, etc.?
255 @cindex File-name conventions
256 @cindex Conventions for file names
257 @cindex Directories and files that come with Emacs
258
259 These are files that come with Emacs. The Emacs distribution is divided
260 into subdirectories; e.g., @file{etc}, @file{lisp}, and @file{src}.
261 Some of these (e.g., @file{etc} and @file{lisp}) are present both in
262 an installed Emacs and in the sources, but some (e.g., @file{src}) are
263 only found in the sources.
264
265 If you use Emacs, but don't know where it is kept on your system, start
266 Emacs, then type @kbd{C-h v data-directory @key{RET}}. The directory
267 name displayed by this will be the full pathname of the installed
268 @file{etc} directory. (This full path is recorded in the Emacs variable
269 @code{data-directory}, and @kbd{C-h v} displays the value and the
270 documentation of a variable.)
271
272 The location of your Info directory (i.e., where Info documentation
273 is stored) is kept in the variable @code{Info-default-directory-list}. Use
274 @kbd{C-h v Info-default-directory-list @key{RET}} to see the value of
275 this variable, which will be a list of directory names. The last
276 directory in that list is probably where most Info files are stored. By
277 default, Emacs Info documentation is placed in @file{/usr/local/share/info}.
278
279 For information on some of the files in the @file{etc} directory,
280 @pxref{Informational files for Emacs}.
281
282 @node Common acronyms
283 @section What are FSF, LPF, GNU, RMS, FTP, and GPL?
284 @cindex FSF, definition of
285 @cindex LPF, definition of
286 @cindex GNU, definition of
287 @cindex RMS, definition of
288 @cindex Stallman, Richard, acronym for
289 @cindex Richard Stallman, acronym for
290 @cindex FTP, definition of
291 @cindex GPL, definition of
292 @cindex Acronyms, definitions for
293 @cindex Common acronyms, definitions for
294
295 @table @asis
296
297 @item FSF
298 Free Software Foundation
299
300 @item LPF
301 League for Programming Freedom
302
303 @item GNU
304 GNU's Not Unix
305
306 @item RMS
307 Richard Matthew Stallman
308
309 @item FTP
310 File Transfer Protocol
311
312 @item GPL
313 GNU General Public License
314
315 @end table
316
317 Avoid confusing the FSF and the LPF@. The LPF opposes
318 look-and-feel copyrights and software patents. The FSF aims to make
319 high quality free software available for everyone.
320
321 The word ``free'' in the title of the Free Software Foundation refers to
322 ``freedom,'' not ``zero cost.'' Anyone can charge any price for
323 GPL-covered software that they want to. However, in practice, the
324 freedom enforced by the GPL leads to low prices, because you can always
325 get the software for less money from someone else, since everyone has
326 the right to resell or give away GPL-covered software.
327
328 @c ------------------------------------------------------------
329 @node General questions
330 @chapter General questions
331 @cindex General questions
332
333 This chapter contains general questions having to do with Emacs, the
334 Free Software Foundation, and related organizations.
335
336 @menu
337 * The LPF::
338 * Real meaning of copyleft::
339 * Guidelines for newsgroup postings::
340 * Newsgroup archives::
341 * Reporting bugs::
342 * Unsubscribing from Emacs lists::
343 * Contacting the FSF::
344 @end menu
345
346 @node The LPF
347 @section What is the LPF?
348 @cindex LPF, description of
349 @cindex League for Programming Freedom
350 @cindex Software patents, opposition to
351 @cindex Patents for software, opposition to
352
353 The LPF opposes the expanding danger of software patents and
354 look-and-feel copyrights. More information on the LPF's views is
355 available at @uref{http://progfree.org/, the LPF home page}.
356
357 @node Real meaning of copyleft
358 @section What is the real legal meaning of the GNU copyleft?
359 @cindex Copyleft, real meaning of
360 @cindex GPL, real meaning of
361 @cindex General Public License, real meaning of
362 @cindex Discussion of the GPL
363
364 The real legal meaning of the GNU General Public License (copyleft) will
365 only be known if and when a judge rules on its validity and scope.
366 There has never been a copyright infringement case involving the GPL to
367 set any precedents. Although legal actions have been brought against
368 companies for violating the terms of the GPL, so far all have been
369 settled out of court (in favor of the plaintiffs). Please take any
370 discussion regarding this issue to the newsgroup
371 @uref{news:gnu.misc.discuss}, which was created to hold the extensive
372 flame wars on the subject.
373
374 RMS writes:
375
376 @quotation
377 The legal meaning of the GNU copyleft is less important than the spirit,
378 which is that Emacs is a free software project and that work pertaining
379 to Emacs should also be free software. ``Free'' means that all users
380 have the freedom to study, share, change and improve Emacs. To make
381 sure everyone has this freedom, pass along source code when you
382 distribute any version of Emacs or a related program, and give the
383 recipients the same freedom that you enjoyed.
384 @end quotation
385
386 @node Guidelines for newsgroup postings
387 @section What are appropriate messages for the various Emacs newsgroups?
388 @cindex Newsgroups, appropriate messages for
389 @cindex GNU newsgroups, appropriate messages for
390 @cindex Usenet groups, appropriate messages for
391 @cindex Mailing lists, appropriate messages for
392 @cindex Posting messages to newsgroups
393
394 @cindex GNU mailing lists
395 The Emacs mailing lists are described at
396 @uref{http://savannah.gnu.org/mail/?group=emacs, the Emacs Savannah
397 page}. Some of them are gatewayed to newsgroups.
398
399 The newsgroup @uref{news:comp.emacs} is for discussion of Emacs programs
400 in general. The newsgroup @uref{news:gnu.emacs.help} is specifically
401 for GNU Emacs. It therefore makes no sense to cross-post to both
402 groups, since only one can be appropriate to any question.
403
404 Messages advocating ``non-free'' software are considered unacceptable on
405 any of the @code{gnu.*} newsgroups except for @uref{news:gnu.misc.discuss},
406 which was created to hold the extensive flame-wars on the subject.
407 ``Non-free'' software includes any software for which the end user can't
408 freely modify the source code and exchange enhancements. Be careful to
409 remove the @code{gnu.*} groups from the @samp{Newsgroups:} line when
410 posting a followup that recommends such software.
411
412 @uref{news:gnu.emacs.bug} is a place where bug reports appear, but avoid
413 posting bug reports to this newsgroup directly (@pxref{Reporting bugs}).
414
415 @node Newsgroup archives
416 @section Where can I get old postings to @uref{news:gnu.emacs.help} and other GNU groups?
417 @cindex Archived postings from @code{gnu.emacs.help}
418 @cindex Usenet archives for GNU groups
419 @cindex Old Usenet postings for GNU groups
420
421 The FSF has maintained archives of all of the GNU mailing lists for many
422 years, although there may be some unintentional gaps in coverage. The
423 archive can be browsed over the web at
424 @uref{http://lists.gnu.org/archive/html/, the GNU mail archive}. Raw
425 files can be downloaded from @uref{ftp://lists.gnu.org/}.
426
427 Web-based Usenet search services, such as
428 @uref{http://groups.google.com/groups/dir?q=gnu&, Google}, also
429 archive the @code{gnu.*} groups.
430
431 You can also read the archives of the @code{gnu.*} groups and post new
432 messages at @uref{http://gmane.org/, Gmane}. Gmane is a service that
433 presents mailing lists as newsgroups (even those without a traditional
434 mail-to-news gateway).
435
436 @node Reporting bugs
437 @section Where should I report bugs and other problems with Emacs?
438 @cindex Bug reporting
439 @cindex Good bug reports
440 @cindex How to submit a bug report
441 @cindex Reporting bugs
442
443 The correct way to report Emacs bugs is to use the command
444 @kbd{M-x report-emacs-bug}. It sets up a mail buffer with the
445 essential information and the correct e-mail address,
446 @email{bug-gnu-emacs@@gnu.org}.
447 Anything sent there also appears in the
448 newsgroup @uref{news:gnu.emacs.bug}, but please use e-mail instead of
449 news to submit the bug report. This ensures a reliable return address
450 so you can be contacted for further details.
451
452 Be sure to read the ``Bugs'' section of the Emacs manual before reporting
453 a bug! The manual describes in detail how to submit a useful bug
454 report (@pxref{Bugs, , Reporting Bugs, emacs, The GNU Emacs Manual}).
455 (@xref{Emacs manual}, if you don't know how to read the manual.)
456
457 RMS says:
458
459 @quotation
460 Sending bug reports to
461 @url{http://lists.gnu.org/mailman/listinfo/help-gnu-emacs,
462 the help-gnu-emacs mailing list}
463 (which has the effect of posting on @uref{news:gnu.emacs.help}) is
464 undesirable because it takes the time of an unnecessarily large group
465 of people, most of whom are just users and have no idea how to fix
466 these problem.
467 @url{http://lists.gnu.org/mailman/listinfo/bug-gnu-emacs, The
468 bug-gnu-emacs list} reaches a much smaller group of people who are
469 more likely to know what to do and have expressed a wish to receive
470 more messages about Emacs than the others.
471 @end quotation
472
473 RMS says it is sometimes fine to post to @uref{news:gnu.emacs.help}:
474
475 @quotation
476 If you have reported a bug and you don't hear about a possible fix,
477 then after a suitable delay (such as a week) it is okay to post on
478 @code{gnu.emacs.help} asking if anyone can help you.
479 @end quotation
480
481 If you are unsure whether you have found a bug, consider the following
482 non-exhaustive list, courtesy of RMS:
483
484 @quotation
485 If Emacs crashes, that is a bug. If Emacs gets compilation errors
486 while building, that is a bug. If Emacs crashes while building, that
487 is a bug. If Lisp code does not do what the documentation says it
488 does, that is a bug.
489 @end quotation
490
491 @node Unsubscribing from Emacs lists
492 @section How do I unsubscribe from a mailing list?
493 @cindex Unsubscribing from GNU mailing lists
494 @cindex Removing yourself from GNU mailing lists
495
496 If you are receiving a GNU mailing list named @var{list}, you should be
497 able to unsubscribe from it by sending a request to the address
498 @email{@var{list}-request@@gnu.org}. Mailing lists mails normally
499 contain information in either the message header
500 (@samp{List-Unsubscribe:}) or as a footer that tells you how to
501 unsubscribe.
502
503 @node Contacting the FSF
504 @section How do I contact the FSF?
505 @cindex Contracting the FSF
506 @cindex Free Software Foundation, contacting
507
508 For up-to-date information, see
509 @uref{http://www.fsf.org/about/contact.html, the FSF contact web-page}.
510 You can send general correspondence to @email{info@@fsf.org}.
511
512 @cindex Ordering GNU software
513 For details on how to order items directly from the FSF, see the
514 @uref{http://shop.fsf.org/, FSF on-line store}.
515
516 @c ------------------------------------------------------------
517 @node Getting help
518 @chapter Getting help
519 @cindex Getting help
520
521 This chapter tells you how to get help with Emacs.
522
523 @menu
524 * Basic editing::
525 * Learning how to do something::
526 * Getting a printed manual::
527 * Emacs Lisp documentation::
528 * Installing Texinfo documentation::
529 * Printing a Texinfo file::
530 * Viewing Info files outside of Emacs::
531 * Informational files for Emacs::
532 * Help installing Emacs::
533 * Obtaining the FAQ::
534 @end menu
535
536 @node Basic editing
537 @section I'm just starting Emacs; how do I do basic editing?
538 @cindex Basic editing with Emacs
539 @cindex Beginning editing
540 @cindex Tutorial, invoking the
541 @cindex Self-paced tutorial, invoking the
542 @cindex Help system, entering the
543
544 Type @kbd{C-h t} to invoke the self-paced tutorial. Just typing
545 @kbd{C-h} enters the help system. Starting with Emacs 22, the tutorial
546 is available in many foreign languages such as French, German, Japanese,
547 Russian, etc. Use @kbd{M-x help-with-tutorial-spec-language @key{RET}}
548 to choose your language and start the tutorial.
549
550 Your system administrator may have changed @kbd{C-h} to act like
551 @key{DEL} to deal with local keyboards. You can use @kbd{M-x
552 help-for-help} instead to invoke help. To discover what key (if any)
553 invokes help on your system, type @kbd{M-x where-is @key{RET}
554 help-for-help @key{RET}}. This will print a comma-separated list of key
555 sequences in the echo area. Ignore the last character in each key
556 sequence listed. Each of the resulting key sequences (e.g., @key{F1} is
557 common) invokes help.
558
559 Emacs help works best if it is invoked by a single key whose value
560 should be stored in the variable @code{help-char}.
561
562 Some Emacs slides and tutorials can be found at
563 @uref{http://web.psung.name/emacs/}.
564
565 @node Learning how to do something
566 @section How do I find out how to do something in Emacs?
567 @cindex Help for Emacs
568 @cindex Learning to do something in Emacs
569 @cindex Reference card for Emacs
570 @cindex Overview of help systems
571
572 There are several methods for finding out how to do things in Emacs.
573
574 @itemize @bullet
575
576 @cindex Reading the Emacs manual
577 @item
578 The complete text of the Emacs manual is available via the Info
579 hypertext reader. Type @kbd{C-h r} to display the manual in Info mode.
580 Typing @key{h} immediately after entering Info will provide a short
581 tutorial on how to use it.
582
583 @cindex Lookup a subject in a manual
584 @cindex Index search in a manual
585 @item
586 To quickly locate the section of the manual which discusses a certain
587 issue, or describes a command or a variable, type @kbd{C-h i m emacs
588 @key{RET} i @var{topic} @key{RET}}, where @var{topic} is the name of the
589 topic, the command, or the variable which you are looking for. If this
590 does not land you on the right place in the manual, press @kbd{,}
591 (comma) repeatedly until you find what you need. (The @kbd{i} and
592 @kbd{,} keys invoke the index-searching functions, which look for the
593 @var{topic} you type in all the indices of the Emacs manual.)
594
595 @cindex Apropos
596 @item
597 You can list all of the commands whose names contain a certain word
598 (actually which match a regular expression) using @kbd{C-h a} (@kbd{M-x
599 command-apropos}).
600
601 @cindex Command description in the manual
602 @item
603 The command @kbd{C-h F} (@code{Info-goto-emacs-command-node}) prompts
604 for the name of a command, and then attempts to find the section in the
605 Emacs manual where that command is described.
606
607 @cindex Finding commands and variables
608 @item
609 You can list all of the functions and variables whose names contain a
610 certain word using @kbd{M-x apropos}.
611
612 @item
613 You can list all of the functions and variables whose documentation
614 matches a regular expression or a string, using @kbd{M-x
615 apropos-documentation}.
616
617 @item
618 You can order a hardcopy of the manual from the FSF@. @xref{Getting a
619 printed manual}.
620
621 @cindex Reference cards, in other languages
622 @item
623 You can get a printed reference card listing commands and keys to
624 invoke them. You can order one from the FSF for $2 (or 10 for $18),
625 or you can print your own from the @file{etc/refcards/refcard.tex} or
626 @file{etc/refcards/refcard.pdf} files in the Emacs distribution.
627 Beginning with version 21.1, the Emacs distribution comes with
628 translations of the reference card into several languages; look for
629 files named @file{etc/refcards/@var{lang}-refcard.*}, where @var{lang}
630 is a two-letter code of the language. For example, the German version
631 of the reference card is in the files @file{etc/refcards/de-refcard.tex}
632 and @file{etc/refcards/de-refcard.pdf}.
633
634 @item
635 There are many other commands in Emacs for getting help and
636 information. To get a list of these commands, type @samp{?} after
637 @kbd{C-h}.
638
639 @end itemize
640
641 @node Getting a printed manual
642 @section How do I get a printed copy of the Emacs manual?
643 @cindex Printed Emacs manual, obtaining
644 @cindex Manual, obtaining a printed or HTML copy of
645 @cindex Emacs manual, obtaining a printed or HTML copy of
646
647 You can order a printed copy of the Emacs manual from the FSF@. For
648 details see the @uref{http://shop.fsf.org/, FSF on-line store}.
649
650 The full Texinfo source for the manual also comes in the @file{doc/emacs}
651 directory of the Emacs distribution, if you're daring enough to try to
652 print out this several-hundred-page manual yourself (@pxref{Printing a Texinfo
653 file}).
654
655 If you absolutely have to print your own copy, and you don't have @TeX{},
656 you can get a PostScript or PDF (or HTML) version from
657
658 @uref{http://www.gnu.org/software/emacs/manual/}
659
660 @xref{Learning how to do something}, for how to view the manual from Emacs.
661
662 @node Emacs Lisp documentation
663 @section Where can I get documentation on Emacs Lisp?
664 @cindex Documentation on Emacs Lisp
665 @cindex Function documentation
666 @cindex Variable documentation
667 @cindex Emacs Lisp Reference Manual
668 @cindex Reference manual for Emacs Lisp
669
670 Within Emacs, you can type @kbd{C-h f} to get the documentation for a
671 function, @kbd{C-h v} for a variable.
672
673 For more information, the Emacs Lisp Reference Manual is available
674 in Info format (@pxref{Top, Emacs Lisp,, elisp, The
675 Emacs Lisp Reference Manual}).
676
677 You can also order a hardcopy of the manual from the FSF, for details
678 see the @uref{http://shop.fsf.org/, FSF on-line store}. (This manual is
679 not always in print.)
680
681 An HTML version of the Emacs Lisp Reference Manual is available at
682
683 @uref{http://www.gnu.org/software/emacs/elisp-manual/elisp.html}
684
685 @node Installing Texinfo documentation
686 @section How do I install a piece of Texinfo documentation?
687 @cindex Texinfo documentation, installing
688 @cindex Installing Texinfo documentation
689 @cindex New Texinfo files, installing
690 @cindex Documentation, installing new Texinfo files
691 @cindex Info files, how to install
692
693 Emacs releases come with pre-built Info files, and the normal install
694 process places them in the correct location. This is true for most
695 applications that provide Info files. The following section is only
696 relevant if you want to install extra Info files by hand.
697
698 First, you must turn the Texinfo source files into Info files. You may
699 do this using the stand-alone @file{makeinfo} program, available as part
700 of the Texinfo package at
701
702 @uref{http://www.gnu.org/software/texinfo/}
703
704 For information about the Texinfo format, read the Texinfo manual which
705 comes with the Texinfo package. This manual also comes installed in
706 Info format, so you can read it from Emacs; type @kbd{C-h i m texinfo
707 @key{RET}}.
708
709 @c FIXME is this a complete alternative?
710 @c Probably not, given that we require makeinfo to build Emacs.
711 Alternatively, you could use the Emacs command @kbd{M-x
712 texinfo-format-buffer}, after visiting the Texinfo source file of the
713 manual you want to convert.
714
715 Neither @code{texinfo-format-buffer} nor @file{makeinfo} installs the
716 resulting Info files in Emacs's Info tree. To install Info files,
717 perform these steps:
718
719 @enumerate
720 @item
721 Move the files to the @file{info} directory in the installed Emacs
722 distribution. @xref{File-name conventions}, if you don't know where that
723 is.
724
725 @item
726 Run the @code{install-info} command, which is part of the Texinfo
727 distribution, to update the main Info directory menu, like this:
728
729 @example
730 install-info --info-dir=@var{dir-path} @var{dir-path}/@var{file}
731 @end example
732
733 @noindent
734 where @var{dir-path} is the full path to the directory where you copied
735 the produced Info file(s), and @var{file} is the name of the Info file
736 you produced and want to install.
737
738 If you don't have the @code{install-info} command installed, you can
739 edit the file @file{info/dir} in the installed Emacs distribution, and
740 add a line for the top level node in the Info package that you are
741 installing. Follow the examples already in this file. The format is:
742
743 @example
744 * Topic: (relative-pathname). Short description of topic.
745 @end example
746
747 @end enumerate
748
749 If you want to install Info files and you don't have the necessary
750 privileges, you have several options:
751
752 @itemize @bullet
753 @item
754 Info files don't actually need to be installed before being used.
755 You can use a prefix argument for the @code{info} command and specify
756 the name of the Info file in the minibuffer. This goes to the node
757 named @samp{Top} in that file. For example, to view a Info file named
758 @file{@var{info-file}} in your home directory, you can type this:
759
760 @example
761 @kbd{C-u C-h i ~/@var{info-file} @key{RET}}
762 @end example
763
764 Alternatively, you can feed a file name to the @code{Info-goto-node}
765 command (invoked by pressing @key{g} in Info mode) by typing the name
766 of the file in parentheses, like this:
767
768 @example
769 @kbd{C-h i g (~/@var{info-file}) @key{RET}}
770 @end example
771
772 @item
773 You can create your own Info directory. You can tell Emacs where that
774 Info directory is by adding its pathname to the value of the variable
775 @code{Info-default-directory-list}. For example, to use a private Info
776 directory which is a subdirectory of your home directory named @file{Info},
777 you could put this in your @file{.emacs} file:
778
779 @lisp
780 (add-to-list 'Info-default-directory-list "~/Info")
781 @end lisp
782
783 You will need a top-level Info file named @file{dir} in this directory
784 which has everything the system @file{dir} file has in it, except it
785 should list only entries for Info files in that directory. You might
786 not need it if (fortuitously) all files in this directory were
787 referenced by other @file{dir} files. The node lists from all
788 @file{dir} files in @code{Info-default-directory-list} are merged by the
789 Info system.
790
791 @end itemize
792
793 @node Printing a Texinfo file
794 @section How do I print a Texinfo file?
795 @cindex Printing a Texinfo file
796 @cindex Texinfo file, printing
797 @cindex Printing documentation
798
799 You can't get nicely printed output from Info files; you must still have
800 the original Texinfo source file for the manual you want to print.
801
802 Assuming you have @TeX{} installed on your system, follow these steps:
803
804 @enumerate
805
806 @item
807 Make sure the first line of the Texinfo file looks like this:
808
809 @example
810 \input texinfo
811 @end example
812
813 You may need to change @samp{texinfo} to the full pathname of the
814 @file{texinfo.tex} file, which comes with Emacs as
815 @file{doc/misc/texinfo.tex} (or copy or link it into the current directory).
816
817 @item
818 Type @kbd{texi2dvi @var{texinfo-source}}, where @var{texinfo-source} is
819 the name of the Texinfo source file for which you want to produce a
820 printed copy. The @samp{texi2dvi} script is part of the GNU Texinfo
821 distribution.
822
823 Alternatively, @samp{texi2pdf} produces PDF files.
824
825 @item
826 Print the DVI file @file{@var{texinfo-source}.dvi} in the normal way for
827 printing DVI files at your site. For example, if you have a PostScript
828 printer, run the @code{dvips} program to print the DVI file on that
829 printer.
830
831 @end enumerate
832
833 To get more general instructions, retrieve the latest Texinfo package
834 (@pxref{Installing Texinfo documentation}).
835
836 @node Viewing Info files outside of Emacs
837 @section Can I view Info files without using Emacs?
838 @cindex Viewing Info files
839 @cindex Info file viewers
840 @cindex Alternative Info file viewers
841
842 Yes. Here are some alternative programs:
843
844 @itemize @bullet
845
846 @item
847 @code{info}, a stand-alone version of the Info program, comes as part of
848 the Texinfo package. @xref{Installing Texinfo documentation}, for
849 details.
850
851 @item
852 Tkinfo, an Info viewer that runs under X Window system and uses Tcl/Tk.
853 You can get Tkinfo at
854 @uref{http://math-www.uni-paderborn.de/~axel/tkinfo/}.
855
856 @end itemize
857
858 @node Informational files for Emacs
859 @section What informational files are available for Emacs?
860 @cindex Informational files included with Emacs
861 @cindex Files included with Emacs
862 @cindex @file{COPYING}, description of file
863 @cindex @file{DISTRIB}, description of file
864 @cindex @file{GNU}, description of file
865 @cindex @file{MACHINES}, description of file
866 @cindex @file{NEWS}, description of file
867
868 This isn't a frequently asked question, but it should be! A variety of
869 informational files about Emacs and relevant aspects of the GNU project
870 are available for you to read.
871
872 The following files (and others) are available in the @file{etc}
873 directory of the Emacs distribution (see @ref{File-name conventions}, if
874 you're not sure where that is). Many of these files are available via
875 the Emacs @samp{Help} menu, or by typing @kbd{C-h ?} (@kbd{M-x
876 help-for-help}).
877
878 @table @file
879
880 @item COPYING
881 GNU General Public License
882
883 @item DISTRIB
884 Emacs Availability Information
885
886 @item GNU
887 The GNU Manifesto
888
889 @item MACHINES
890 Status of Emacs on Various Machines and Systems
891
892 @item NEWS
893 Emacs news, a history of recent user-visible changes
894
895 @end table
896
897 More GNU information, including back issues of the @cite{GNU's
898 Bulletin}, are at
899
900 @uref{http://www.gnu.org/bulletins/bulletins.html} and
901
902 @uref{http://www.cs.pdx.edu/~trent/gnu/gnu.html}
903
904 @node Help installing Emacs
905 @section Where can I get help in installing Emacs?
906 @cindex Installation help
907 @cindex Help installing Emacs
908
909 @xref{Installing Emacs}, for some basic installation hints, and see
910 @ref{Problems building Emacs}, if you have problems with the installation.
911
912 @uref{http://www.fsf.org/resources/service/, The GNU Service directory}
913 lists companies and individuals willing to sell you help in installing
914 or using Emacs and other GNU software.
915
916 @node Obtaining the FAQ
917 @section Where can I get the latest version of this FAQ?
918 @cindex FAQ, obtaining the
919 @cindex Latest FAQ version, obtaining the
920
921 The Emacs FAQ is distributed with Emacs in Info format. You can read it
922 by selecting the @samp{Emacs FAQ} option from the @samp{Help} menu of
923 the Emacs menu bar at the top of any Emacs frame, or by typing @kbd{C-h
924 C-f} (@kbd{M-x view-emacs-FAQ}). The very latest version is available
925 in the Emacs development repository (@pxref{Latest version of Emacs}).
926
927 @c ------------------------------------------------------------
928 @node Status of Emacs
929 @chapter Status of Emacs
930 @cindex Status of Emacs
931
932 This chapter gives you basic information about Emacs, including the
933 status of its latest version.
934
935 @menu
936 * Origin of the term Emacs::
937 * Latest version of Emacs::
938 * New in Emacs 24::
939 * New in Emacs 23::
940 * New in Emacs 22::
941 * New in Emacs 21::
942 * New in Emacs 20::
943 @end menu
944
945 @node Origin of the term Emacs
946 @section Where does the name ``Emacs'' come from?
947 @cindex Origin of the term ``Emacs''
948 @cindex Emacs name origin
949 @cindex TECO
950 @cindex Original version of Emacs
951
952 Emacs originally was an acronym for Editor MACroS@. RMS says he ``picked
953 the name Emacs because @key{E} was not in use as an abbreviation on ITS at
954 the time.'' The first Emacs was a set of macros written in 1976 at MIT
955 by RMS for the editor TECO (Text Editor and COrrector, originally Tape
956 Editor and COrrector) under ITS (the Incompatible Timesharing System) on
957 a PDP-10. RMS had already extended TECO with a ``real-time''
958 full-screen mode with reprogrammable keys. Emacs was started by
959 @c gls@@east.sun.com
960 Guy Steele as a project to unify the many
961 divergent TECO command sets and key bindings at MIT, and completed by
962 RMS.
963
964 Many people have said that TECO code looks a lot like line noise; you
965 can read more at @uref{news:alt.lang.teco}. Someone has written a TECO
966 implementation in Emacs Lisp (to find it, see @ref{Packages that do not
967 come with Emacs}); it would be an interesting project to run the
968 original TECO Emacs inside of Emacs.
969
970 @cindex Why Emacs?
971 For some not-so-serious alternative reasons for Emacs to have that
972 name, check out the file @file{etc/JOKES} (@pxref{File-name
973 conventions}).
974
975 @node Latest version of Emacs
976 @section What is the latest version of Emacs?
977 @cindex Version, latest
978 @cindex Latest version of Emacs
979 @cindex Development, Emacs
980 @cindex Repository, Emacs
981 @cindex Bazaar repository, Emacs
982
983 Emacs @value{EMACSVER} is the current version as of this writing. A version
984 number with two components (e.g., @samp{22.1}) indicates a released
985 version; three components indicate a development
986 version (e.g., @samp{23.0.50} is what will eventually become @samp{23.1}).
987
988 Emacs is under active development, hosted at
989 @uref{http://savannah.gnu.org/projects/emacs/, Savannah}.
990 Follow the instructions given there to clone the project repository.
991
992 Because Emacs undergoes many changes before a release, the version
993 number of a development version is not especially meaningful. It is
994 better to refer to the date on which the sources were retrieved from the
995 development repository. The development version is usually quite robust
996 for every-day use, but if stability is more important to you than the
997 latest features, you may want to stick to the releases.
998
999 The following sections list some of the major new features in the last
1000 few Emacs releases. For full details of the changes in any version of
1001 Emacs, type @kbd{C-h C-n} (@kbd{M-x view-emacs-news}). As of Emacs 22,
1002 you can give this command a prefix argument to read about which features
1003 were new in older versions.
1004
1005 @node New in Emacs 24
1006 @section What is different about Emacs 24?
1007 @cindex Differences between Emacs 23 and Emacs 24
1008 @cindex Emacs 24, new features in
1009
1010 @itemize
1011 @cindex packages, installing more
1012 @item
1013 Emacs now includes a package manager. Type @kbd{M-x list-packages} to
1014 get started. You can use this to download and automatically install
1015 many more Lisp packages.
1016
1017 @cindex lexical binding
1018 @item
1019 Emacs Lisp now supports lexical binding on a per-file basis. In
1020 @emph{lexical binding}, variable references must be located textually
1021 within the binding construct. This contrasts with @emph{dynamic
1022 binding}, where programs can refer to variables defined outside their
1023 local textual scope. A Lisp file can use a local variable setting of
1024 @code{lexical-binding: t} to indicate that the contents should be
1025 interpreted using lexical binding. See the Emacs Lisp Reference
1026 Manual for more details.
1027
1028 @cindex bidirectional display
1029 @cindex right-to-left languages
1030 @item
1031 Some human languages, such as English, are written from left to right.
1032 Others, such as Arabic, are written from right to left. Emacs now has
1033 support for any mixture of these forms---this is ``bidirectional text''.
1034
1035 @item
1036 Handling of text selections has been improved, and now integrates
1037 better with external clipboards.
1038
1039 @cindex themes
1040 @item
1041 A new command @kbd{customize-themes} allows you to easily change the
1042 appearance of your Emacs.
1043
1044 @item
1045 Emacs can be compiled with the GTK+ 3 toolkit.
1046
1047 @item
1048 Support for several new external libraries can be included at compile
1049 time:
1050
1051 @itemize
1052
1053 @item
1054 ``Security-Enhanced Linux'' (SELinux) is a Linux kernel feature that
1055 provides more sophisticated file access controls than ordinary
1056 ``Unix-style'' file permissions.
1057
1058 @item
1059 The ImageMagick display library. This allows you to display many more
1060 image format in Emacs, as well as carry out transformations such as
1061 rotations.
1062
1063 @item
1064 The GnuTLS library for secure network communications. Emacs uses this
1065 transparently for email if your mail server supports it.
1066
1067 @item
1068 The libxml2 library for parsing XML structures.
1069 @end itemize
1070
1071 @item
1072 Much more flexibility in the handling of windows and buffer display.
1073
1074 @end itemize
1075
1076 As always, consult the @file{NEWS} file for more information.
1077
1078
1079 @node New in Emacs 23
1080 @section What is different about Emacs 23?
1081 @cindex Differences between Emacs 22 and Emacs 23
1082 @cindex Emacs 23, new features in
1083
1084 @itemize
1085
1086 @cindex Anti-aliased fonts
1087 @cindex Freetype fonts
1088 @item
1089 Emacs has a new font code that can use multiple font backends,
1090 including freetype and fontconfig. Emacs can use the Xft library for
1091 anti-aliasing, and the otf and m17n libraries for complex text layout and
1092 text shaping.
1093
1094 @cindex Unicode
1095 @cindex Character sets
1096 @item
1097 The Emacs character set is now a superset of Unicode. Several new
1098 language environments have been added.
1099
1100 @cindex Multi-tty support
1101 @cindex X and tty displays
1102 @item
1103 Emacs now supports using both X displays and ttys in the same session
1104 (@samp{multi-tty}).
1105
1106 @cindex Daemon mode
1107 @item
1108 Emacs can be started as a daemon in the background.
1109
1110 @cindex NeXTstep port
1111 @cindex GNUstep port
1112 @cindex Mac OS X Cocoa
1113 @item
1114 There is a new NeXTstep port of Emacs. This supports GNUstep and Mac OS
1115 X (via the Cocoa libraries). The Carbon port of Emacs, which supported
1116 Mac OS X in Emacs 22, has been removed.
1117
1118 @cindex Directory-local variables
1119 @item
1120 Directory-local variables can now be defined, in a similar manner to
1121 file-local variables.
1122
1123 @item
1124 Transient Mark mode (@pxref{Highlighting a region}) is on by default.
1125
1126 @end itemize
1127
1128 @noindent
1129 Other changes include: support for serial port access; D-Bus bindings; a
1130 new Visual Line mode for line-motion; improved completion; a new mode
1131 (@samp{DocView}) for viewing of PDF, PostScript, and DVI documents; nXML
1132 mode (for editing XML documents) is included; VC has been updated for
1133 newer version control systems; etc.
1134
1135
1136 @node New in Emacs 22
1137 @section What is different about Emacs 22?
1138 @cindex Differences between Emacs 21 and Emacs 22
1139 @cindex Emacs 22, new features in
1140
1141 @itemize
1142 @cindex GTK+ Toolkit
1143 @cindex Drag-and-drop
1144 @item
1145 Emacs can be built with GTK+ widgets, and supports drag-and-drop
1146 operation on X.
1147
1148 @cindex Supported systems
1149 @item
1150 Emacs 22 features support for GNU/Linux systems on S390 and x86-64
1151 machines, as well as support for the Mac OS X and Cygwin operating
1152 systems.
1153
1154 @item
1155 The native MS-Windows, and Mac OS X builds include full support
1156 for images, toolbar, and tooltips.
1157
1158 @item
1159 Font Lock mode, Auto Compression mode, and File Name Shadow Mode are
1160 enabled by default.
1161
1162 @item
1163 The maximum size of buffers is increased: on 32-bit machines, it is
1164 256 MBytes for Emacs 23.1, and 512 MBytes for Emacs 23.2 and above.
1165
1166 @item
1167 Links can be followed with @kbd{mouse-1}, in addition to @kbd{mouse-2}.
1168
1169 @cindex Mouse wheel
1170 @item
1171 Mouse wheel support is enabled by default.
1172
1173 @item
1174 Window fringes are customizable.
1175
1176 @item
1177 The mode line of the selected window is now highlighted.
1178
1179 @item
1180 The minibuffer prompt is displayed in a distinct face.
1181
1182 @item
1183 Abbrev definitions are read automatically at startup.
1184
1185 @item
1186 Grep mode is separate from Compilation mode and has many new options and
1187 commands specific to grep.
1188
1189 @item
1190 The original Emacs macro system has been replaced by the new Kmacro
1191 package, which provides many new commands and features and a simple
1192 interface that uses the function keys F3 and F4. Macros are stored in a
1193 macro ring, and can be debugged and edited interactively.
1194
1195 @item
1196 The Grand Unified Debugger (GUD) can be used with a full graphical user
1197 interface to GDB; this provides many features found in traditional
1198 development environments, making it easy to manipulate breakpoints, add
1199 watch points, display the call stack, etc. Breakpoints are visually
1200 indicated in the source buffer.
1201
1202 @item
1203 @cindex New modes
1204 Many new modes and packages have been included in Emacs, such as Calc,
1205 TRAMP, URL, IDO, CUA, ERC, rcirc, Table, Image-Dired, SES, Ruler, Org,
1206 PGG, Flymake, Password, Printing, Reveal, wdired, t-mouse, longlines,
1207 savehist, Conf mode, Python mode, DNS mode, etc.
1208
1209 @cindex Multilingual Environment
1210 @item
1211 Leim is now part of Emacs. Unicode support has been much improved, and
1212 the following input methods have been added: belarusian, bulgarian-bds,
1213 bulgarian-phonetic, chinese-sisheng, croatian, dutch, georgian,
1214 latin-alt-postfix, latin-postfix, latin-prefix, latvian-keyboard,
1215 lithuanian-numeric, lithuanian-keyboard, malayalam-inscript, rfc1345,
1216 russian-computer, sgml, slovenian, tamil-inscript, ucs,
1217 ukrainian-computer, vietnamese-telex, and welsh.
1218
1219 The following language environments have also been added: Belarusian,
1220 Bulgarian, Chinese-EUC-TW, Croatian, French, Georgian, Italian, Latin-6,
1221 Latin-7, Latvian, Lithuanian, Malayalam, Russian, Slovenian, Swedish,
1222 Tajik, Tamil, UTF-8, Ukrainian, Welsh, and Windows-1255.
1223
1224 @cindex Documentation
1225 @cindex Emacs Lisp Manual
1226 @item
1227 In addition, Emacs 22 now includes the Emacs Lisp Reference Manual
1228 (@pxref{Emacs Lisp documentation}) and the Emacs Lisp Intro.
1229 @end itemize
1230
1231
1232 @node New in Emacs 21
1233 @section What is different about Emacs 21?
1234 @cindex Differences between Emacs 20 and Emacs 21
1235 @cindex Emacs 21, new features in
1236
1237 @cindex Variable-size fonts
1238 @cindex Toolbar support
1239 Emacs 21 features a thorough rewrite of the display engine. The new
1240 display engine supports variable-size fonts, images, and can play sounds
1241 on platforms which support that. As a result, the visual appearance of
1242 Emacs, when it runs on a windowed display, is much more reminiscent of
1243 modern GUI programs, and includes 3D widgets (used for the mode line and
1244 the scroll bars), a configurable and extensible toolbar, tooltips
1245 (a.k.a.@: balloon help), and other niceties.
1246
1247 @cindex Colors on text-only terminals
1248 @cindex TTY colors
1249 In addition, Emacs 21 supports faces on text-only terminals. This means
1250 that you can now have colors when you run Emacs on a GNU/Linux console
1251 and on @code{xterm} with @kbd{emacs -nw}.
1252
1253
1254 @node New in Emacs 20
1255 @section What is different about Emacs 20?
1256 @cindex Differences between Emacs 19 and Emacs 20
1257 @cindex Emacs 20, new features in
1258
1259 The differences between Emacs versions 18 and 19 were rather dramatic;
1260 the introduction of frames, faces, and colors on windowing systems was
1261 obvious to even the most casual user.
1262
1263 There are differences between Emacs versions 19 and 20 as well, but many
1264 are more subtle or harder to find. Among the changes are the inclusion
1265 of MULE code for languages that use non-Latin characters and for mixing
1266 several languages in the same document; the ``Customize'' facility for
1267 modifying variables without having to use Lisp; and automatic conversion
1268 of files from Macintosh, Microsoft, and Unix platforms.
1269
1270 @c ------------------------------------------------------------
1271 @node Common requests
1272 @chapter Common requests
1273 @cindex Common requests
1274
1275 @menu
1276 * Setting up a customization file::
1277 * Using Customize::
1278 * Colors on a TTY::
1279 * Debugging a customization file::
1280 * Displaying the current line or column::
1281 * Displaying the current file name in the titlebar::
1282 * Turning on abbrevs by default::
1283 * Associating modes with files::
1284 * Highlighting a region::
1285 * Replacing highlighted text::
1286 * Controlling case sensitivity::
1287 * Working with unprintable characters::
1288 * Searching for/replacing newlines::
1289 * Yanking text in isearch::
1290 * Wrapping words automatically::
1291 * Turning on auto-fill by default::
1292 * Changing load-path::
1293 * Using an already running Emacs process::
1294 * Compiler error messages::
1295 * Indenting switch statements::
1296 * Customizing C and C++ indentation::
1297 * Horizontal scrolling::
1298 * Overwrite mode::
1299 * Turning off beeping::
1300 * Turning the volume down::
1301 * Automatic indentation::
1302 * Matching parentheses::
1303 * Hiding #ifdef lines::
1304 * Repeating commands::
1305 * Valid X resources::
1306 * Evaluating Emacs Lisp code::
1307 * Changing the length of a Tab::
1308 * Inserting text at the beginning of each line::
1309 * Forcing the cursor to remain in the same column::
1310 * Forcing Emacs to iconify itself::
1311 * Using regular expressions::
1312 * Replacing text across multiple files::
1313 * Documentation for etags::
1314 * Disabling backups::
1315 * Disabling auto-save-mode::
1316 * Going to a line by number::
1317 * Modifying pull-down menus::
1318 * Deleting menus and menu options::
1319 * Turning on syntax highlighting::
1320 * Scrolling only one line::
1321 * Editing MS-DOS files::
1322 * Filling paragraphs with a single space::
1323 * Escape sequences in shell output::
1324 * Fullscreen mode on MS-Windows::
1325 @end menu
1326
1327 @node Setting up a customization file
1328 @section How do I set up a @file{.emacs} file properly?
1329 @cindex @file{.emacs} file, setting up
1330 @cindex @file{.emacs} file, locating
1331 @cindex Init file, setting up
1332 @cindex Customization file, setting up
1333
1334 @xref{Init File,,, emacs, The GNU Emacs Manual}.
1335
1336 In general, new Emacs users should not be provided with @file{.emacs}
1337 files, because this can cause confusing non-standard behavior. Then
1338 they send questions to
1339 @url{http://lists.gnu.org/mailman/listinfo/help-gnu-emacs,
1340 the help-gnu-emacs mailing list} asking why Emacs
1341 isn't behaving as documented.
1342
1343 Emacs includes the Customize facility (@pxref{Using Customize}). This
1344 allows users who are unfamiliar with Emacs Lisp to modify their
1345 @file{.emacs} files in a relatively straightforward way, using menus
1346 rather than Lisp code.
1347
1348 While Customize might indeed make it easier to configure Emacs,
1349 consider taking a bit of time to learn Emacs Lisp and modifying your
1350 @file{.emacs} directly. Simple configuration options are described
1351 rather completely in @ref{Init File,,, emacs, The GNU Emacs Manual},
1352 for users interested in performing frequently requested, basic tasks.
1353
1354 Sometimes users are unsure as to where their @file{.emacs} file should
1355 be found. Visiting the file as @file{~/.emacs} from Emacs will find
1356 the correct file.
1357
1358 @node Using Customize
1359 @section How do I start using Customize?
1360 @cindex Customize groups
1361 @cindex Customizing variables
1362 @cindex Customizing faces
1363
1364 The main Customize entry point is @kbd{M-x customize @key{RET}}. This
1365 command takes you to a buffer listing all the available Customize
1366 groups. From there, you can access all customizable options and faces,
1367 change their values, and save your changes to your init file.
1368 @xref{Easy Customization,,, emacs, The GNU Emacs Manual}.
1369
1370 If you know the name of the group in advance (e.g., ``shell''), use
1371 @kbd{M-x customize-group @key{RET}}.
1372
1373 If you wish to customize a single option, use @kbd{M-x customize-option
1374 @key{RET}}. This command prompts you for the name of the option to
1375 customize, with completion.
1376
1377 @node Colors on a TTY
1378 @section How do I get colors and syntax highlighting on a TTY?
1379 @cindex Colors on a TTY
1380 @cindex Syntax highlighting on a TTY
1381 @cindex Console, colors
1382
1383 In Emacs 21.1 and later, colors and faces are supported in non-windowed mode,
1384 i.e., on Unix and GNU/Linux text-only terminals and consoles, and when
1385 invoked as @samp{emacs -nw} on X, and MS-Windows. (Colors and faces were
1386 supported in the MS-DOS port since Emacs 19.29.) Emacs automatically
1387 detects color support at startup and uses it if available. If you think
1388 that your terminal supports colors, but Emacs won't use them, check the
1389 @code{termcap} entry for your display type for color-related
1390 capabilities.
1391
1392 The command @kbd{M-x list-colors-display} pops up a window which
1393 exhibits all the colors Emacs knows about on the current display.
1394
1395 Syntax highlighting is on by default since version 22.1.
1396
1397 @node Debugging a customization file
1398 @section How do I debug a @file{.emacs} file?
1399 @cindex Debugging @file{.emacs} file
1400 @cindex @file{.emacs} debugging
1401 @cindex Init file debugging
1402 @cindex @samp{-debug-init} option
1403
1404 Start Emacs with the @samp{-debug-init} command-line option. This
1405 enables the Emacs Lisp debugger before evaluating your @file{.emacs}
1406 file, and places you in the debugger if something goes wrong. The top
1407 line in the @file{trace-back} buffer will be the error message, and the
1408 second or third line of that buffer will display the Lisp code from your
1409 @file{.emacs} file that caused the problem.
1410
1411 You can also evaluate an individual function or argument to a function
1412 in your @file{.emacs} file by moving the cursor to the end of the
1413 function or argument and typing @kbd{C-x C-e} (@kbd{M-x
1414 eval-last-sexp}).
1415
1416 Use @kbd{C-h v} (@kbd{M-x describe-variable}) to check the value of
1417 variables which you are trying to set or use.
1418
1419 @node Displaying the current line or column
1420 @section How do I make Emacs display the current line (or column) number?
1421 @cindex @code{line-number-mode}
1422 @cindex Displaying the current line or column
1423 @cindex Line number, displaying the current
1424 @cindex Column, displaying the current
1425 @cindex @code{mode-line-format}
1426
1427 By default, Emacs displays the current line number of the point in the
1428 mode line. You can toggle this feature off or on with the command
1429 @kbd{M-x line-number-mode}, or by setting the variable
1430 @code{line-number-mode}. Note that Emacs will not display the line
1431 number if the buffer's size in bytes is larger than the value of the
1432 variable @code{line-number-display-limit}.
1433
1434 You can similarly display the current column with
1435 @kbd{M-x column-number-mode}, or by putting the form
1436
1437 @lisp
1438 (setq column-number-mode t)
1439 @end lisp
1440
1441 @noindent
1442 in your @file{.emacs} file. This feature is off by default.
1443
1444 The @code{"%c"} format specifier in the variable @code{mode-line-format}
1445 will insert the current column's value into the mode line. See the
1446 documentation for @code{mode-line-format} (using @kbd{C-h v
1447 mode-line-format @key{RET}}) for more information on how to set and use
1448 this variable.
1449
1450 @cindex Set number capability in @code{vi} emulators
1451 The @samp{linum} package (distributed with Emacs since version 23.1)
1452 displays line numbers in the left margin, like the ``set number''
1453 capability of @code{vi}. The packages @samp{setnu} and
1454 @samp{wb-line-number} (not distributed with Emacs) also implement this
1455 feature.
1456
1457 @node Displaying the current file name in the titlebar
1458 @section How can I modify the titlebar to contain the current file name?
1459 @cindex Titlebar, displaying the current file name in
1460 @cindex File name, displaying in the titlebar
1461 @cindex @code{frame-title-format}
1462
1463 The contents of an Emacs frame's titlebar is controlled by the variable
1464 @code{frame-title-format}, which has the same structure as the variable
1465 @code{mode-line-format}. (Use @kbd{C-h v} or @kbd{M-x
1466 describe-variable} to get information about one or both of these
1467 variables.)
1468
1469 By default, the titlebar for a frame does contain the name of the buffer
1470 currently being visited, except if there is a single frame. In such a
1471 case, the titlebar contains Emacs invocation name and the name of the
1472 machine at which Emacs was invoked. This is done by setting
1473 @code{frame-title-format} to the default value of
1474
1475 @lisp
1476 (multiple-frames "%b" ("" invocation-name "@@" system-name))
1477 @end lisp
1478
1479 To modify the behavior such that frame titlebars contain the buffer's
1480 name regardless of the number of existing frames, include the following
1481 in your @file{.emacs}:
1482
1483 @lisp
1484 (setq frame-title-format "%b")
1485 @end lisp
1486
1487 @node Turning on abbrevs by default
1488 @section How do I turn on abbrevs by default just in mode @var{mymode}?
1489 @cindex Abbrevs, turning on by default
1490
1491 Abbrev mode expands abbreviations as you type them. To turn it on in a
1492 specific buffer, use @kbd{M-x abbrev-mode}. To turn it on in every
1493 buffer by default, put this in your @file{.emacs} file:
1494
1495 @lisp
1496 (setq-default abbrev-mode t)
1497 @end lisp
1498
1499 @noindent To turn it on in a specific mode, use:
1500
1501 @lisp
1502 (add-hook '@var{mymode}-mode-hook
1503 (lambda ()
1504 (setq abbrev-mode t)))
1505 @end lisp
1506
1507 @noindent If your Emacs version is older then 22.1, you will also need to use:
1508
1509 @lisp
1510 (condition-case ()
1511 (quietly-read-abbrev-file)
1512 (file-error nil))
1513 @end lisp
1514
1515 @node Associating modes with files
1516 @section How do I make Emacs use a certain major mode for certain files?
1517 @cindex Associating modes with files
1518 @cindex File extensions and modes
1519 @cindex @code{auto-mode-alist}, modifying
1520 @cindex Modes, associating with file extensions
1521
1522 If you want to use a certain mode @var{foo} for all files whose names end
1523 with the extension @file{.@var{bar}}, this will do it for you:
1524
1525 @lisp
1526 (add-to-list 'auto-mode-alist '("\\.@var{bar}\\'" . @var{foo}-mode))
1527 @end lisp
1528
1529 Alternatively, put this somewhere in the first line of any file you want to
1530 edit in the mode @var{foo} (in the second line, if the first line begins
1531 with @samp{#!}):
1532
1533 @example
1534 -*- @var{foo} -*-
1535 @end example
1536
1537 @cindex Major mode for shell scripts
1538 The variable @code{interpreter-mode-alist} specifies which mode to use
1539 when loading an interpreted script (e.g., shell, python, etc.). Emacs
1540 determines which interpreter you're using by examining the first line of
1541 the script. Use @kbd{C-h v} (or @kbd{M-x describe-variable}) on
1542 @code{interpreter-mode-alist} to learn more.
1543
1544 @node Highlighting a region
1545 @section How can I highlight a region of text in Emacs?
1546 @cindex Highlighting text
1547 @cindex Text, highlighting
1548 @cindex @code{transient-mark-mode}
1549 @cindex Region, highlighting a
1550
1551 You can cause the region to be highlighted when the mark is active by
1552 including
1553
1554 @lisp
1555 (transient-mark-mode 1)
1556 @end lisp
1557
1558 @noindent
1559 in your @file{.emacs} file. Since Emacs 23.1, this feature is on by default.
1560
1561 @node Replacing highlighted text
1562 @section How can I replace highlighted text with what I type?
1563 @cindex @code{delete-selection-mode}
1564 @cindex Replacing highlighted text
1565 @cindex Highlighting and replacing text
1566
1567 Use @code{delete-selection-mode}, which you can start automatically by
1568 placing the following Lisp form in your @file{.emacs} file:
1569
1570 @lisp
1571 (delete-selection-mode 1)
1572 @end lisp
1573
1574 According to the documentation string for @code{delete-selection-mode}
1575 (which you can read using @kbd{M-x describe-function @key{RET}
1576 delete-selection-mode @key{RET}}):
1577
1578 @quotation
1579 When Delete Selection mode is enabled, typed text replaces the selection
1580 if the selection is active. Otherwise, typed text is just inserted at
1581 point regardless of any selection.
1582 @end quotation
1583
1584 This mode also allows you to delete (not kill) the highlighted region by
1585 pressing @key{DEL}.
1586
1587 @node Controlling case sensitivity
1588 @section How do I control Emacs's case-sensitivity when searching/replacing?
1589 @cindex @code{case-fold-search}
1590 @cindex Case sensitivity of searches
1591 @cindex Searching without case sensitivity
1592 @cindex Ignoring case in searches
1593
1594 @c FIXME
1595 The value of the variable @code{case-fold-search} determines whether
1596 searches are case sensitive:
1597
1598 @lisp
1599 (setq case-fold-search nil) ; make searches case sensitive
1600 (setq case-fold-search t) ; make searches case insensitive
1601 @end lisp
1602
1603 @cindex Case sensitivity in replacements
1604 @cindex Replacing, and case sensitivity
1605 @cindex @code{case-replace}
1606 Similarly, for replacing, the variable @code{case-replace} determines
1607 whether replacements preserve case.
1608
1609 You can also toggle case sensitivity at will in isearch with @kbd{M-c}.
1610
1611 To change the case sensitivity just for one major mode, use the major
1612 mode's hook. For example:
1613
1614 @lisp
1615 (add-hook '@var{foo}-mode-hook
1616 (lambda ()
1617 (setq case-fold-search nil)))
1618 @end lisp
1619
1620 @node Working with unprintable characters
1621 @section How do I search for, delete, or replace unprintable (eight-bit or control) characters?
1622 @cindex Unprintable characters, working with
1623 @cindex Working with unprintable characters
1624 @cindex Control characters, working with
1625 @cindex Eight-bit characters, working with
1626 @cindex Searching for unprintable characters
1627 @cindex Regexps and unprintable characters
1628
1629 To search for a single character that appears in the buffer as, for
1630 example, @samp{\237}, you can type @kbd{C-s C-q 2 3 7}.
1631 Searching for @strong{all} unprintable characters is best done with a
1632 regular expression (@dfn{regexp}) search. The easiest regexp to use for
1633 the unprintable chars is the complement of the regexp for the printable
1634 chars.
1635
1636 @itemize @bullet
1637
1638 @item
1639 Regexp for the printable chars: @samp{[\t\n\r\f -~]}
1640
1641 @item
1642 Regexp for the unprintable chars: @samp{[^\t\n\r\f -~]}
1643
1644 @end itemize
1645
1646 To type these special characters in an interactive argument to
1647 @code{isearch-forward-regexp} or @code{re-search-forward}, you need to
1648 use @kbd{C-q}. (@samp{\t}, @samp{\n}, @samp{\r}, and @samp{\f} stand
1649 respectively for @key{TAB}, @key{LFD}, @key{RET}, and @kbd{C-l}.) So,
1650 to search for unprintable characters using @code{re-search-forward}:
1651
1652 @kbd{M-x re-search-forward @key{RET} [^ @key{TAB} C-q @key{LFD} C-q @key{RET} C-q C-l @key{SPC} -~] @key{RET}}
1653
1654 Using @code{isearch-forward-regexp}:
1655
1656 @kbd{C-M-s [^ @key{TAB} @key{LFD} C-q @key{RET} C-q C-l @key{SPC} -~]}
1657
1658 To delete all unprintable characters, simply use replace-regexp:
1659
1660 @kbd{M-x replace-regexp @key{RET} [^ @key{TAB} C-q @key{LFD} C-q @key{RET} C-q C-l @key{SPC} -~] @key{RET} @key{RET}}
1661
1662 Replacing is similar to the above. To replace all unprintable
1663 characters with a colon, use:
1664
1665 M-x replace-regexp @key{RET} [^ @key{TAB} C-q @key{LFD} C-q @key{RET} C-q C-l @key{SPC} -~] @key{RET} : @key{RET}
1666
1667 @node Searching for/replacing newlines
1668 @section How do I input a newline character in isearch or query-replace?
1669 @cindex Searching for newlines
1670 @cindex Replacing newlines
1671
1672 Use @kbd{C-q C-j}. For more information,
1673 @pxref{Special Isearch,, Special Input for Incremental Search, emacs,
1674 The GNU Emacs Manual}.
1675
1676 @node Yanking text in isearch
1677 @section How do I copy text from the kill ring into the search string?
1678 @cindex Yanking text into the search string
1679 @cindex isearch yanking
1680
1681 Use @kbd{M-y}. @xref{Isearch Yank,,, emacs, The GNU Emacs Manual}.
1682
1683 @node Wrapping words automatically
1684 @section How do I make Emacs wrap words for me?
1685 @cindex Wrapping word automatically
1686 @cindex Wrapping lines
1687 @cindex Line wrap
1688 @cindex @code{auto-fill-mode}, introduction to
1689 @cindex Maximum line width, default value
1690 @cindex @code{fill-column}, default value
1691
1692 Use @code{auto-fill-mode}, activated by typing @kbd{M-x auto-fill-mode}.
1693 The default maximum line width is 70, determined by the variable
1694 @code{fill-column}. To learn how to turn this on automatically, see
1695 @ref{Turning on auto-fill by default}.
1696
1697 @node Turning on auto-fill by default
1698 @section How do I turn on @code{auto-fill-mode} by default?
1699 @cindex @code{auto-fill-mode}, activating automatically
1700 @cindex Filling automatically
1701 @cindex Automatic entry to @code{auto-fill-mode}
1702
1703 To turn on @code{auto-fill-mode} just once for one buffer, use @kbd{M-x
1704 auto-fill-mode}.
1705
1706 To turn it on for every buffer in a certain mode, you must use the hook
1707 for that mode. For example, to turn on @code{auto-fill} mode for all
1708 text buffers, including the following in your @file{.emacs} file:
1709
1710 @lisp
1711 (add-hook 'text-mode-hook 'turn-on-auto-fill)
1712 @end lisp
1713
1714 If you want @code{auto-fill} mode on in all major modes, do this:
1715
1716 @lisp
1717 (setq-default auto-fill-function 'do-auto-fill)
1718 @end lisp
1719
1720 @node Changing load-path
1721 @section How do I change @code{load-path}?
1722 @cindex @code{load-path}, modifying
1723 @cindex Modifying @code{load-path}
1724 @cindex Adding to @code{load-path}
1725
1726 In general, you should only add to the @code{load-path}. You can add
1727 directory @var{/dir/subdir} to the load path like this:
1728
1729 @lisp
1730 (add-to-list 'load-path "/dir/subdir/")
1731 @end lisp
1732
1733 To do this relative to your home directory:
1734
1735 @lisp
1736 (add-to-list 'load-path "~/mysubdir/")
1737 @end lisp
1738
1739 @node Using an already running Emacs process
1740 @section How do I use an already running Emacs from another window?
1741 @cindex @code{emacsclient}
1742 @cindex Emacs server functions
1743 @cindex Using an existing Emacs process
1744
1745 @code{emacsclient}, which comes with Emacs, is for editing a file using
1746 an already running Emacs rather than starting up a new Emacs. It does
1747 this by sending a request to the already running Emacs, which must be
1748 expecting the request.
1749
1750 @itemize @bullet
1751
1752 @item
1753 Setup:
1754
1755 Emacs must have executed the @code{server-start} function for
1756 @samp{emacsclient} to work. This can be done either by a command line
1757 option:
1758
1759 @example
1760 emacs -f server-start
1761 @end example
1762
1763 or by invoking @code{server-start} from @file{.emacs}:
1764
1765 @lisp
1766 (if (@var{some conditions are met}) (server-start))
1767 @end lisp
1768
1769 When this is done, Emacs creates a Unix domain socket named
1770 @file{server} in @file{/tmp/emacs@var{userid}}. See
1771 @code{server-socket-dir}.
1772
1773 To get your news reader, mail reader, etc., to invoke
1774 @samp{emacsclient}, try setting the environment variable @code{EDITOR}
1775 (or sometimes @code{VISUAL}) to the value @samp{emacsclient}. You may
1776 have to specify the full pathname of the @samp{emacsclient} program
1777 instead. Examples:
1778
1779 @example
1780 # csh commands:
1781 setenv EDITOR emacsclient
1782
1783 # using full pathname
1784 setenv EDITOR /usr/local/emacs/etc/emacsclient
1785
1786 # sh command:
1787 EDITOR=emacsclient ; export EDITOR
1788 @end example
1789
1790 @item
1791 Normal use:
1792
1793 When @samp{emacsclient} is run, it connects to the socket and passes its
1794 command line options to Emacs, which at the next opportunity will visit
1795 the files specified. (Line numbers can be specified just like with
1796 Emacs.) The user will have to switch to the Emacs window by hand. When
1797 the user is done editing a file, the user can type @kbd{C-x #} (or
1798 @kbd{M-x server-edit}) to indicate this. If there is another buffer
1799 requested by @code{emacsclient}, Emacs will switch to it; otherwise
1800 @code{emacsclient} will exit, signaling the calling program to continue.
1801
1802 @cindex @code{gnuserv}
1803 There is an alternative version of @samp{emacsclient} called
1804 @c ange@@hplb.hpl.hp.com
1805 @samp{gnuserv}, written by Andy Norman
1806 (@pxref{Packages that do not come with Emacs}). @samp{gnuserv} uses
1807 Internet domain sockets, so it can work across most network connections.
1808
1809 The most recent @samp{gnuserv} package is available at
1810
1811 @uref{http://meltin.net/hacks/emacs/}
1812
1813 @end itemize
1814
1815 @node Compiler error messages
1816 @section How do I make Emacs recognize my compiler's funny error messages?
1817 @cindex Compiler error messages, recognizing
1818 @cindex Recognizing non-standard compiler errors
1819 @cindex Regexps for recognizing compiler errors
1820 @cindex Errors, recognizing compiler
1821
1822 Customize the @code{compilation-error-regexp-alist} variable.
1823
1824 @node Indenting switch statements
1825 @section How do I change the indentation for @code{switch}?
1826 @cindex @code{switch}, indenting
1827 @cindex Indenting of @code{switch}
1828
1829 Many people want to indent their @code{switch} statements like this:
1830
1831 @example
1832 f()
1833 @{
1834 switch(x) @{
1835 case A:
1836 x1;
1837 break;
1838 case B:
1839 x2;
1840 break;
1841 default:
1842 x3;
1843 @}
1844 @}
1845 @end example
1846
1847 @noindent To achieve this, add the following line to your @file{.emacs}:
1848
1849 @lisp
1850 (c-set-offset 'case-label '+)
1851 @end lisp
1852
1853 @node Customizing C and C++ indentation
1854 @section How to customize indentation in C, C@t{++}, and Java buffers?
1855 @cindex Indentation, how to customize
1856 @cindex Customize indentation
1857
1858 The Emacs @code{cc-mode} features an interactive procedure for
1859 customizing the indentation style, which is fully explained in the
1860 @cite{CC Mode} manual that is part of the Emacs distribution, see
1861 @ref{Customizing Indentation, , Customization Indentation, ccmode,
1862 The CC Mode Manual}. Here's a short summary of the procedure:
1863
1864 @enumerate
1865 @item
1866 Go to the beginning of the first line where you don't like the
1867 indentation and type @kbd{C-c C-o}. Emacs will prompt you for the
1868 syntactic symbol; type @key{RET} to accept the default it suggests.
1869
1870 @item
1871 Emacs now prompts for the offset of this syntactic symbol, showing the
1872 default (the current definition) inside parentheses. You can choose
1873 one of these:
1874
1875 @table @code
1876 @item 0
1877 No extra indentation.
1878 @item +
1879 Indent one basic offset.
1880 @item -
1881 Outdent one basic offset.
1882 @item ++
1883 Indent two basic offsets
1884 @item --
1885 Outdent two basic offsets.
1886 @item *
1887 Indent half basic offset.
1888 @item /
1889 Outdent half basic offset.
1890 @end table
1891
1892 @item
1893 After choosing one of these symbols, type @kbd{C-c C-q} to reindent
1894 the line or the block according to what you just specified.
1895
1896 @item
1897 If you don't like the result, go back to step 1. Otherwise, add the
1898 following line to your @file{.emacs}:
1899
1900 @lisp
1901 (c-set-offset '@var{syntactic-symbol} @var{offset})
1902 @end lisp
1903
1904 @noindent
1905 where @var{syntactic-symbol} is the name Emacs shows in the minibuffer
1906 when you type @kbd{C-c C-o} at the beginning of the line, and
1907 @var{offset} is one of the indentation symbols listed above (@code{+},
1908 @code{/}, @code{0}, etc.)@: that you've chosen during the interactive
1909 procedure.
1910
1911 @item
1912 Go to the next line whose indentation is not to your liking and repeat
1913 the process there.
1914 @end enumerate
1915
1916 It is recommended to put all the resulting @code{(c-set-offset ...)}
1917 customizations inside a C mode hook, like this:
1918
1919 @lisp
1920 (defun my-c-mode-hook ()
1921 (c-set-offset ...)
1922 (c-set-offset ...))
1923 (add-hook 'c-mode-hook 'my-c-mode-hook)
1924 @end lisp
1925
1926 @noindent
1927 Using @code{c-mode-hook} avoids the need to put a @w{@code{(require
1928 'cc-mode)}} into your @file{.emacs} file, because @code{c-set-offset}
1929 might be unavailable when @code{cc-mode} is not loaded.
1930
1931 Note that @code{c-mode-hook} runs for C source files only; use
1932 @code{c++-mode-hook} for C@t{++} sources, @code{java-mode-hook} for
1933 Java sources, etc. If you want the same customizations to be in
1934 effect in @emph{all} languages supported by @code{cc-mode}, use
1935 @code{c-mode-common-hook}.
1936
1937 @node Horizontal scrolling
1938 @section How can I make Emacs automatically scroll horizontally?
1939 @cindex @code{hscroll-mode}
1940 @cindex Horizontal scrolling
1941 @cindex Scrolling horizontally
1942
1943 In Emacs 21 and later, this is on by default: if the variable
1944 @code{truncate-lines} is non-@code{nil} in the current buffer, Emacs
1945 automatically scrolls the display horizontally when point moves off the
1946 left or right edge of the window.
1947
1948 Note that this is overridden by the variable
1949 @code{truncate-partial-width-windows} if that variable is non-@code{nil}
1950 and the current buffer is not full-frame width.
1951
1952 In Emacs 20, use @code{hscroll-mode}.
1953
1954 @node Overwrite mode
1955 @section How do I make Emacs ``typeover'' or ``overwrite'' instead of inserting?
1956 @cindex @key{Insert}
1957 @cindex @code{overwrite-mode}
1958 @cindex Overwriting existing text
1959 @cindex Toggling @code{overwrite-mode}
1960
1961 @kbd{M-x overwrite-mode} (a minor mode). This toggles
1962 @code{overwrite-mode} on and off, so exiting from @code{overwrite-mode}
1963 is as easy as another @kbd{M-x overwrite-mode}.
1964
1965 On some systems, @key{Insert} toggles @code{overwrite-mode} on and off.
1966
1967 @node Turning off beeping
1968 @section How do I stop Emacs from beeping on a terminal?
1969 @cindex Beeping, turning off
1970 @cindex Visible bell
1971 @cindex Bell, visible
1972
1973 @c martin@@cc.gatech.edu
1974 Martin R. Frank writes:
1975
1976 Tell Emacs to use the @dfn{visible bell} instead of the audible bell,
1977 and set the visible bell to nothing.
1978
1979 That is, put the following in your @code{TERMCAP} environment variable
1980 (assuming you have one):
1981
1982 @example
1983 ... :vb=: ...
1984 @end example
1985
1986 And evaluate the following Lisp form:
1987
1988 @example
1989 (setq visible-bell t)
1990 @end example
1991
1992 @node Turning the volume down
1993 @section How do I turn down the bell volume in Emacs running under X?
1994 @cindex Bell, volume of
1995 @cindex Volume of bell
1996
1997 On X Window system, you can adjust the bell volume and duration for all
1998 programs with the shell command @code{xset}.
1999
2000 Invoking @code{xset} without any arguments produces some basic
2001 information, including the following:
2002
2003 @example
2004 usage: xset [-display host:dpy] option ...
2005 To turn bell off:
2006 -b b off b 0
2007 To set bell volume, pitch and duration:
2008 b [vol [pitch [dur]]] b on
2009 @end example
2010
2011 @node Automatic indentation
2012 @section How do I tell Emacs to automatically indent a new line to the indentation of the previous line?
2013 @cindex Indenting new lines
2014 @cindex New lines, indenting of
2015 @cindex Previous line, indenting according to
2016 @cindex Text indentation
2017
2018 Such behavior is automatic (in Text mode) in Emacs 20 and later. From the
2019 @file{etc/NEWS} file for Emacs 20.2:
2020
2021 @example
2022 ** In Text mode, now only blank lines separate paragraphs. This makes
2023 it possible to get the full benefit of Adaptive Fill mode in Text mode,
2024 and other modes derived from it (such as Mail mode). @key{TAB} in Text
2025 mode now runs the command @code{indent-relative}; this makes a practical
2026 difference only when you use indented paragraphs.
2027
2028 If you want spaces at the beginning of a line to start a paragraph, use
2029 the new mode, Paragraph Indent Text mode.
2030 @end example
2031
2032 @cindex Prefixing lines
2033 @cindex Fill prefix
2034 If you have @code{auto-fill-mode} turned on (@pxref{Turning on auto-fill
2035 by default}), you can tell Emacs to prefix every line with a certain
2036 character sequence, the @dfn{fill prefix}. Type the prefix at the
2037 beginning of a line, position point after it, and then type @kbd{C-x .}
2038 (@code{set-fill-prefix}) to set the fill prefix. Thereafter,
2039 auto-filling will automatically put the fill prefix at the beginning of
2040 new lines, and @kbd{M-q} (@code{fill-paragraph}) will maintain any fill
2041 prefix when refilling the paragraph.
2042
2043 If you have paragraphs with different levels of indentation, you will
2044 have to set the fill prefix to the correct value each time you move to a
2045 new paragraph. There are many packages available to deal with this
2046 (@pxref{Packages that do not come with Emacs}). Look for ``fill'' and
2047 ``indent'' keywords for guidance.
2048
2049 @node Matching parentheses
2050 @section How do I show which parenthesis matches the one I'm looking at?
2051 @cindex Parentheses, matching
2052 @cindex @file{paren.el}
2053 @cindex Highlighting matching parentheses
2054 @cindex Pairs of parentheses, highlighting
2055 @cindex Matching parentheses
2056
2057 Call @code{show-paren-mode} in your @file{.emacs} file:
2058
2059 @lisp
2060 (show-paren-mode 1)
2061 @end lisp
2062
2063 You can also enable this mode by selecting the @samp{Paren Match
2064 Highlighting} option from the @samp{Options} menu of the Emacs menu bar
2065 at the top of any Emacs frame.
2066
2067 Alternatives to this mode include:
2068
2069 @itemize @bullet
2070
2071 @item
2072 If you're looking at a right parenthesis (or brace or bracket) you can
2073 delete it and reinsert it. Emacs will momentarily move the cursor to
2074 the matching parenthesis.
2075
2076 @item
2077 @kbd{C-M-f} (@code{forward-sexp}) and @kbd{C-M-b} (@code{backward-sexp})
2078 will skip over one set of balanced parentheses, so you can see which
2079 parentheses match. (You can train it to skip over balanced brackets
2080 and braces at the same time by modifying the syntax table.)
2081
2082 @cindex Show matching paren as in @code{vi}
2083 @item
2084 Here is some Emacs Lisp that will make the @key{%} key show the matching
2085 parenthesis, like in @code{vi}. In addition, if the cursor isn't over a
2086 parenthesis, it simply inserts a % like normal.
2087
2088 @lisp
2089 ;; By an unknown contributor
2090
2091 (global-set-key "%" 'match-paren)
2092
2093 (defun match-paren (arg)
2094 "Go to the matching paren if on a paren; otherwise insert %."
2095 (interactive "p")
2096 (cond ((looking-at "\\s\(") (forward-list 1) (backward-char 1))
2097 ((looking-at "\\s\)") (forward-char 1) (backward-list 1))
2098 (t (self-insert-command (or arg 1)))))
2099 @end lisp
2100
2101 @end itemize
2102
2103 @node Hiding #ifdef lines
2104 @section In C mode, can I show just the lines that will be left after @code{#ifdef} commands are handled by the compiler?
2105 @cindex @code{#ifdef}, selective display of
2106 @cindex @code{hide-ifdef-mode}
2107 @cindex Hiding @code{#ifdef} text
2108 @cindex Selectively displaying @code{#ifdef} code
2109
2110 @kbd{M-x hide-ifdef-mode}. (This is a minor mode.) You might also want
2111 to investigate @file{cpp.el}, which is distributed with Emacs.
2112
2113 @node Repeating commands
2114 @section How do I repeat a command as many times as possible?
2115 @cindex Repeating commands many times
2116 @cindex Commands, repeating many times
2117 @cindex @code{.}, equivalent to @code{vi} command
2118
2119 As of Emacs 20.3, there is indeed a @code{repeat} command (@kbd{C-x z})
2120 that repeats the last command. If you preface it with a prefix
2121 argument, the prefix arg is applied to the command.
2122
2123 You can also type @kbd{C-x @key{ESC} @key{ESC}}
2124 (@code{repeat-complex-command}) to reinvoke commands that used the
2125 minibuffer to get arguments. In @code{repeat-complex-command} you can
2126 type @kbd{M-p} and @kbd{M-n} (and also up-arrow and down-arrow, if your
2127 keyboard has these keys) to scan through all the different complex
2128 commands you've typed.
2129
2130 To repeat a set of commands, use keyboard macros. Use @kbd{C-x (} and
2131 @kbd{C-x )} to make a keyboard macro that invokes the command and then
2132 type @kbd{C-x e}. @xref{Keyboard Macros,,, emacs, The GNU Emacs Manual}.
2133
2134 If you're really desperate for the @code{.} command in @code{vi} that
2135 redoes the last insertion/deletion, use VIPER, a @code{vi} emulation
2136 mode which comes with Emacs, and which appears to support it.
2137
2138 @node Valid X resources
2139 @section What are the valid X resource settings (i.e., stuff in .Xdefaults)?
2140 @cindex Resources, X
2141 @cindex X resources
2142 @cindex Setting X resources
2143
2144 @xref{X Resources,,, emacs, The GNU Emacs Manual}.
2145
2146 You can also use a resource editor, such as editres (for X11R5 and
2147 onwards), to look at the resource names for the menu bar, assuming Emacs
2148 was compiled with the X toolkit.
2149
2150 @node Evaluating Emacs Lisp code
2151 @section How do I execute (``evaluate'') a piece of Emacs Lisp code?
2152 @cindex Evaluating Lisp code
2153 @cindex Lisp forms, evaluating
2154
2155 There are a number of ways to execute (@dfn{evaluate}, in Lisp lingo) an
2156 Emacs Lisp @dfn{form}:
2157
2158 @itemize @bullet
2159
2160 @item
2161 If you want it evaluated every time you run Emacs, put it in a file
2162 named @file{.emacs} in your home directory. This is known as ``your
2163 @file{.emacs} file,'' and contains all of your personal customizations.
2164
2165 @item
2166 You can type the form in the @file{*scratch*} buffer, and then type
2167 @key{LFD} (or @kbd{C-j}) after it. The result of evaluating the form
2168 will be inserted in the buffer.
2169
2170 @item
2171 In @code{emacs-lisp-mode}, typing @kbd{C-M-x} evaluates a top-level form
2172 before or around point.
2173
2174 @item
2175 Typing @kbd{C-x C-e} in any buffer evaluates the Lisp form immediately
2176 before point and prints its value in the echo area.
2177
2178 @item
2179 Typing @kbd{M-:} or @kbd{M-x eval-expression} allows you to type a Lisp
2180 form in the minibuffer which will be evaluated once you press @key{RET}.
2181
2182 @item
2183 You can use @kbd{M-x load-file} to have Emacs evaluate all the Lisp
2184 forms in a file. (To do this from Lisp use the function @code{load}
2185 instead.)
2186
2187 The functions @code{load-library}, @code{eval-region},
2188 @code{eval-buffer}, @code{require}, and @code{autoload} are also
2189 useful; see @ref{Emacs Lisp documentation}, if you want to learn more
2190 about them.
2191
2192 @end itemize
2193
2194 @node Changing the length of a Tab
2195 @section How do I change Emacs's idea of the @key{TAB} character's length?
2196 @cindex Tab length
2197 @cindex Length of tab character
2198
2199 Set the default value of the variable @code{tab-width}. For example, to set
2200 @key{TAB} stops every 10 characters, insert the following in your
2201 @file{.emacs} file:
2202
2203 @lisp
2204 (setq-default tab-width 10)
2205 @end lisp
2206
2207 Do not confuse variable @code{tab-width} with variable
2208 @code{tab-stop-list}. The former is used for the display of literal
2209 @key{TAB} characters. The latter controls what characters are inserted
2210 when you press the @key{TAB} character in certain modes.
2211
2212 @node Inserting text at the beginning of each line
2213 @section How do I insert <some text> at the beginning of every line?
2214 @cindex Prefixing a region with some text
2215 @cindex Prefix character, inserting in mail/news replies
2216 @cindex Replies to mail/news, inserting a prefix character
2217 @cindex @code{mail-yank-prefix}
2218 @cindex Mail replies, inserting a prefix character
2219 @cindex News replies, inserting a prefix character
2220
2221 To do this to an entire buffer, type @kbd{M-< M-x replace-regexp
2222 @key{RET} ^ @key{RET} your text @key{RET}}.
2223
2224 To do this to a region, use @code{string-insert-rectangle}.
2225 Set the mark (@kbd{C-@key{SPC}}) at the beginning of the first line you
2226 want to prefix, move the cursor to last line to be prefixed, and type
2227 @kbd{M-x string-insert-rectangle @key{RET}}. To do this for the whole
2228 buffer, type @kbd{C-x h M-x string-insert-rectangle @key{RET}}.
2229
2230 If you are trying to prefix a yanked mail message with @samp{>}, you
2231 might want to set the variable @code{mail-yank-prefix}. In Message
2232 buffers, you can even use @kbd{M-;} to cite yanked messages (@kbd{M-;}
2233 runs the function @code{comment-region}, it is a general-purpose
2234 mechanism to comment regions) (@pxref{Changing the included text prefix}).
2235
2236 @node Forcing the cursor to remain in the same column
2237 @section 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?
2238 @cindex @code{picture-mode}
2239 @cindex Remaining in the same column, regardless of contents
2240 @cindex Vertical movement in empty documents
2241
2242 Use @kbd{M-x picture-mode}.
2243
2244 See also the variable @code{track-eol} and the command
2245 @code{set-goal-column} bound to @kbd{C-x C-n}
2246 (@pxref{Moving Point, , , emacs, The GNU Emacs Manual}).
2247
2248 @node Forcing Emacs to iconify itself
2249 @section How do I tell Emacs to iconify itself?
2250 @cindex Iconification under the X Window System
2251 @cindex X Window System and iconification
2252 @cindex Suspending Emacs
2253
2254 @kbd{C-z} iconifies Emacs when running under X and suspends Emacs
2255 otherwise. @xref{Frame Commands,,, emacs, The GNU Emacs Manual}.
2256
2257 @node Using regular expressions
2258 @section How do I use regexps (regular expressions) in Emacs?
2259 @cindex Regexps
2260 @cindex Regular expressions
2261 @cindex Differences between Unix and Emacs regexps
2262 @cindex Unix regexps, differences from Emacs
2263 @cindex Text strings, putting regexps in
2264
2265 @xref{Regexp Backslash,,, emacs, The GNU Emacs Manual}.
2266
2267 The @code{or} operator is @samp{\|}, not @samp{|}, and the grouping operators
2268 are @samp{\(} and @samp{\)}. Also, the string syntax for a backslash is
2269 @samp{\\}. To specify a regular expression like @samp{xxx\(foo\|bar\)}
2270 in a Lisp string, use @samp{xxx\\(foo\\|bar\\)}.
2271
2272 Note the doubled backslashes!
2273
2274 @itemize @bullet
2275
2276 @item
2277 Unlike in Unix @file{grep}, @file{sed}, etc., a complement character set
2278 (@samp{[^...]}) can match a newline character (@key{LFD} a.k.a.@:
2279 @kbd{C-j} a.k.a.@: @samp{\n}), unless newline is mentioned as one of the
2280 characters not to match.
2281
2282 @item
2283 The character syntax regexps (e.g., @samp{\sw}) are not
2284 meaningful inside character set regexps (e.g., @samp{[aeiou]}). (This
2285 is actually typical for regexp syntax.)
2286
2287 @end itemize
2288
2289 @node Replacing text across multiple files
2290 @section How do I perform a replace operation across more than one file?
2291 @cindex Replacing strings across files
2292 @cindex Multiple files, replacing across
2293 @cindex Files, replacing strings across multiple
2294 @cindex Recursive search/replace operations
2295
2296 Dired mode (@kbd{M-x dired @key{RET}}, or @kbd{C-x d}) supports the
2297 command @code{dired-do-query-replace-regexp} (@kbd{Q}), which allows
2298 users to replace regular expressions in multiple files.
2299
2300 You can use this command to perform search/replace operations on
2301 multiple files by following the following steps:
2302
2303 @itemize @bullet
2304 @item
2305 Assemble a list of files you want to operate on with either
2306 @code{find-dired}, @code{find-name-dired} or @code{find-grep-dired}.
2307
2308 @item
2309 Mark all files in the resulting Dired buffer using @kbd{t}.
2310
2311 @item
2312 Use @kbd{Q} to start a @code{query-replace-regexp} session on the marked
2313 files.
2314
2315 @item
2316 To accept all replacements in each file, hit @kbd{!}.
2317 @end itemize
2318
2319 Another way to do the same thing is to use the ``tags'' feature of
2320 Emacs: it includes the command @code{tags-query-replace} which performs
2321 a query-replace across all the files mentioned in the @file{TAGS} file.
2322 @xref{Tags Search,,, emacs, The GNU Emacs Manual}.
2323
2324 @node Documentation for etags
2325 @section Where is the documentation for @code{etags}?
2326 @cindex Documentation for @code{etags}
2327 @cindex @code{etags}, documentation for
2328
2329 The @code{etags} man page should be in the same place as the
2330 @code{emacs} man page.
2331
2332 Quick command-line switch descriptions are also available. For example,
2333 @samp{etags -H}.
2334
2335 @node Disabling backups
2336 @section How do I disable backup files?
2337 @cindex Backups, disabling
2338 @cindex Disabling backups
2339
2340 You probably don't want to do this, since backups are useful, especially
2341 when something goes wrong.
2342
2343 To avoid seeing backup files (and other ``uninteresting'' files) in Dired,
2344 load @code{dired-x} by adding the following to your @file{.emacs} file:
2345
2346 @lisp
2347 (add-hook 'dired-load-hook
2348 (lambda ()
2349 (require 'dired-x)))
2350 @end lisp
2351
2352 With @code{dired-x} loaded, @kbd{M-o} toggles omitting in each dired buffer.
2353 You can make omitting the default for new dired buffers by putting the
2354 following in your @file{.emacs}:
2355
2356 @lisp
2357 (add-hook 'dired-mode-hook 'dired-omit-toggle)
2358 @end lisp
2359
2360 If you're tired of seeing backup files whenever you do an @samp{ls} at
2361 the Unix shell, try GNU @code{ls} with the @samp{-B} option. GNU
2362 @code{ls} is part of the GNU Fileutils package, available from
2363 @samp{ftp.gnu.org} and its mirrors (@pxref{Current GNU distributions}).
2364
2365 To disable or change the way backups are made,
2366 @pxref{Backup Names,,, emacs, The GNU Emacs Manual}.
2367
2368 @cindex Backup files in a single directory
2369 Beginning with Emacs 21.1, you can control where Emacs puts backup files
2370 by customizing the variable @code{backup-directory-alist}. This
2371 variable's value specifies that files whose names match specific patters
2372 should have their backups put in certain directories. A typical use is
2373 to add the element @code{("." . @var{dir})} to force Emacs to put
2374 @strong{all} backup files in the directory @file{dir}.
2375
2376 @node Disabling auto-save-mode
2377 @section How do I disable @code{auto-save-mode}?
2378 @cindex Disabling @code{auto-save-mode}
2379 @cindex Auto-saving
2380 @cindex Saving at frequent intervals
2381
2382 You probably don't want to do this, since auto-saving is useful,
2383 especially when Emacs or your computer crashes while you are editing a
2384 document.
2385
2386 Instead, you might want to change the variable
2387 @code{auto-save-interval}, which specifies how many keystrokes Emacs
2388 waits before auto-saving. Increasing this value forces Emacs to wait
2389 longer between auto-saves, which might annoy you less.
2390
2391 You might also want to look into Sebastian Kremer's @code{auto-save}
2392 package (@pxref{Packages that do not come with Emacs}). This
2393 package also allows you to place all auto-save files in one directory,
2394 such as @file{/tmp}.
2395
2396 To disable or change how @code{auto-save-mode} works,
2397 @pxref{Auto Save,,, emacs, The GNU Emacs Manual}.
2398
2399 @node Going to a line by number
2400 @section How can I go to a certain line given its number?
2401 @cindex Going to a line by number
2402 @cindex Compilation error messages
2403 @cindex Recompilation
2404
2405 Are you sure you indeed need to go to a line by its number? Perhaps all
2406 you want is to display a line in your source file for which a compiler
2407 printed an error message? If so, compiling from within Emacs using the
2408 @kbd{M-x compile} and @kbd{M-x recompile} commands is a much more
2409 effective way of doing that. Emacs automatically intercepts the compile
2410 error messages, inserts them into a special buffer called
2411 @file{*compilation*}, and lets you visit the locus of each message in
2412 the source. Type @kbd{C-x `} to step through the offending lines one by
2413 one (starting with Emacs 22, you can also use @kbd{M-g M-p} and
2414 @kbd{M-g M-n} to go to the previous and next matches directly). Click
2415 @kbd{Mouse-2} or press @key{RET} on a message text in the
2416 @file{*compilation*} buffer to go to the line whose number is mentioned
2417 in that message.
2418
2419 But if you indeed need to go to a certain text line, type @kbd{M-g M-g}
2420 (which is the default binding of the @code{goto-line} function starting
2421 with Emacs 22). Emacs will prompt you for the number of the line and go
2422 to that line.
2423
2424 You can do this faster by invoking @code{goto-line} with a numeric
2425 argument that is the line's number. For example, @kbd{C-u 286 M-g M-g}
2426 will jump to line number 286 in the current buffer.
2427
2428 @node Modifying pull-down menus
2429 @section How can I create or modify new pull-down menu options?
2430 @cindex Pull-down menus, creating or modifying
2431 @cindex Menus, creating or modifying
2432 @cindex Creating new menu options
2433 @cindex Modifying pull-down menus
2434 @cindex Menus and keymaps
2435 @cindex Keymaps and menus
2436
2437 Each menu title (e.g., @samp{File}, @samp{Edit}, @samp{Buffers})
2438 represents a local or global keymap. Selecting a menu title with the
2439 mouse displays that keymap's non-@code{nil} contents in the form of a menu.
2440
2441 So to add a menu option to an existing menu, all you have to do is add a
2442 new definition to the appropriate keymap. Adding a @samp{Forward Word}
2443 item to the @samp{Edit} menu thus requires the following Lisp code:
2444
2445 @lisp
2446 (define-key global-map
2447 [menu-bar edit forward]
2448 '("Forward word" . forward-word))
2449 @end lisp
2450
2451 @noindent
2452 The first line adds the entry to the global keymap, which includes
2453 global menu bar entries. Replacing the reference to @code{global-map}
2454 with a local keymap would add this menu option only within a particular
2455 mode.
2456
2457 The second line describes the path from the menu-bar to the new entry.
2458 Placing this menu entry underneath the @samp{File} menu would mean
2459 changing the word @code{edit} in the second line to @code{file}.
2460
2461 The third line is a cons cell whose first element is the title that will
2462 be displayed, and whose second element is the function that will be
2463 called when that menu option is invoked.
2464
2465 To add a new menu, rather than a new option to an existing menu, we must
2466 define an entirely new keymap:
2467
2468 @lisp
2469 (define-key global-map [menu-bar words]
2470 (cons "Words" (make-sparse-keymap "Words")))
2471 @end lisp
2472
2473 The above code creates a new sparse keymap, gives it the name
2474 @samp{Words}, and attaches it to the global menu bar. Adding the
2475 @samp{Forward Word} item to this new menu would thus require the
2476 following code:
2477
2478 @lisp
2479 (define-key global-map
2480 [menu-bar words forward]
2481 '("Forward word" . forward-word))
2482 @end lisp
2483
2484 @noindent
2485 Note that because of the way keymaps work, menu options are displayed
2486 with the more recently defined items at the top. Thus if you were to
2487 define menu options @samp{foo}, @samp{bar}, and @samp{baz} (in that
2488 order), the menu option @samp{baz} would appear at the top, and
2489 @samp{foo} would be at the bottom.
2490
2491 One way to avoid this problem is to use the function @code{define-key-after},
2492 which works the same as @code{define-key}, but lets you modify where items
2493 appear. The following Lisp code would insert the @samp{Forward Word}
2494 item in the @samp{Edit} menu immediately following the @samp{Undo} item:
2495
2496 @lisp
2497 (define-key-after
2498 (lookup-key global-map [menu-bar edit])
2499 [forward]
2500 '("Forward word" . forward-word)
2501 'undo)
2502 @end lisp
2503
2504 Note how the second and third arguments to @code{define-key-after} are
2505 different from those of @code{define-key}, and that we have added a new
2506 (final) argument, the function after which our new key should be
2507 defined.
2508
2509 To move a menu option from one position to another, simply evaluate
2510 @code{define-key-after} with the appropriate final argument.
2511
2512 More detailed information---and more examples of how to create and
2513 modify menu options---are in the @cite{Emacs Lisp Reference Manual}, under
2514 ``Menu Keymaps.'' (@xref{Emacs Lisp documentation}, for information on
2515 this manual.)
2516
2517 @node Deleting menus and menu options
2518 @section How do I delete menus and menu options?
2519 @cindex Deleting menus and menu options
2520 @cindex Menus, deleting
2521
2522 The simplest way to remove a menu is to set its keymap to @samp{nil}.
2523 For example, to delete the @samp{Words} menu (@pxref{Modifying pull-down
2524 menus}), use:
2525
2526 @lisp
2527 (define-key global-map [menu-bar words] nil)
2528 @end lisp
2529
2530 Similarly, removing a menu option requires redefining a keymap entry to
2531 @code{nil}. For example, to delete the @samp{Forward word} menu option
2532 from the @samp{Edit} menu (we added it in @ref{Modifying pull-down
2533 menus}), use:
2534
2535 @lisp
2536 (define-key global-map [menu-bar edit forward] nil)
2537 @end lisp
2538
2539 @node Turning on syntax highlighting
2540 @section How do I turn on syntax highlighting?
2541 @cindex Syntax highlighting
2542 @cindex @code{font-lock-mode}
2543 @cindex Highlighting based on syntax
2544 @cindex Colorizing text
2545 @cindex FAQ, @code{font-lock-mode}
2546
2547 @code{font-lock-mode} is the standard way to have Emacs perform syntax
2548 highlighting in the current buffer. It is enabled by default in Emacs
2549 22.1 and later.
2550
2551 With @code{font-lock-mode} turned on, different types of text will
2552 appear in different colors. For instance, in a programming mode,
2553 variables will appear in one face, keywords in a second, and comments in
2554 a third.
2555
2556 To turn @code{font-lock-mode} off within an existing buffer, use
2557 @kbd{M-x font-lock-mode @key{RET}}.
2558
2559 In Emacs 21 and earlier versions, you could use the following code in
2560 your @file{.emacs} file to turn on @code{font-lock-mode} globally:
2561
2562 @lisp
2563 (global-font-lock-mode 1)
2564 @end lisp
2565
2566 Highlighting a buffer with @code{font-lock-mode} can take quite a while,
2567 and cause an annoying delay in display, so several features exist to
2568 work around this.
2569
2570 @cindex Just-In-Time syntax highlighting
2571 In Emacs 21 and later, turning on @code{font-lock-mode} automatically
2572 activates the new @dfn{Just-In-Time fontification} provided by
2573 @code{jit-lock-mode}. @code{jit-lock-mode} defers the fontification of
2574 portions of buffer until you actually need to see them, and can also
2575 fontify while Emacs is idle. This makes display of the visible portion
2576 of a buffer almost instantaneous. For details about customizing
2577 @code{jit-lock-mode}, type @kbd{C-h f jit-lock-mode @key{RET}}.
2578
2579 @cindex Levels of syntax highlighting
2580 @cindex Decoration level, in @code{font-lock-mode}
2581 In versions of Emacs before 21, different levels of decoration are
2582 available, from slight to gaudy. More decoration means you need to wait
2583 more time for a buffer to be fontified (or a faster machine). To
2584 control how decorated your buffers should become, set the value of
2585 @code{font-lock-maximum-decoration} in your @file{.emacs} file, with a
2586 @code{nil} value indicating default (usually minimum) decoration, and a
2587 @code{t} value indicating the maximum decoration. For the gaudiest
2588 possible look, then, include the line
2589
2590 @lisp
2591 (setq font-lock-maximum-decoration t)
2592 @end lisp
2593
2594 @noindent
2595 in your @file{.emacs} file. You can also set this variable such that
2596 different modes are highlighted in a different ways; for more
2597 information, see the documentation for
2598 @code{font-lock-maximum-decoration} with @kbd{C-h v} (or @kbd{M-x
2599 describe-variable @key{RET}}).
2600
2601 Also see the documentation for the function @code{font-lock-mode},
2602 available by typing @kbd{C-h f font-lock-mode} (@kbd{M-x
2603 describe-function @key{RET} font-lock-mode @key{RET}}).
2604
2605 To print buffers with the faces (i.e., colors and fonts) intact, use
2606 @kbd{M-x ps-print-buffer-with-faces} or @kbd{M-x
2607 ps-print-region-with-faces}. You will need a way to send text to a
2608 PostScript printer, or a PostScript interpreter such as Ghostscript;
2609 consult the documentation of the variables @code{ps-printer-name},
2610 @code{ps-lpr-command}, and @code{ps-lpr-switches} for more details.
2611
2612 @node Scrolling only one line
2613 @section How can I force Emacs to scroll only one line when I move past the bottom of the screen?
2614 @cindex Scrolling only one line
2615 @cindex Reducing the increment when scrolling
2616
2617 Customize the @code{scroll-conservatively} variable with @kbd{M-x
2618 customize-variable @key{RET} scroll-conservatively @key{RET}} and set it
2619 to a large value like, say, 10000. For an explanation of what this
2620 means, @pxref{Auto Scrolling,,, emacs, The GNU Emacs Manual}.
2621
2622 Alternatively, use the following Lisp form in your @file{.emacs}:
2623
2624 @lisp
2625 (setq scroll-conservatively most-positive-fixnum)
2626 @end lisp
2627
2628 @node Editing MS-DOS files
2629 @section How can I edit MS-DOS files using Emacs?
2630 @cindex Editing MS-DOS files
2631 @cindex MS-DOS files, editing
2632 @cindex Microsoft files, editing
2633 @cindex Windows files, editing
2634
2635 As of Emacs 20, detection and handling of MS-DOS (and Windows) files is
2636 performed transparently. You can open MS-DOS files on a Unix system,
2637 edit it, and save it without having to worry about the file format.
2638
2639 When editing an MS-DOS style file, the mode line will indicate that it
2640 is a DOS file. On Unix and GNU/Linux systems, and also on a Macintosh,
2641 the string @samp{(DOS)} will appear near the left edge of the mode line;
2642 on DOS and Windows, where the DOS end-of-line (EOL) format is the
2643 default, a backslash (@samp{\}) will appear in the mode line.
2644
2645 @node Filling paragraphs with a single space
2646 @section How can I tell Emacs to fill paragraphs with a single space after each period?
2647 @cindex One space following periods
2648 @cindex Single space following periods
2649 @cindex Periods, one space following
2650
2651 Add the following line to your @file{.emacs} file:
2652
2653 @lisp
2654 (setq sentence-end-double-space nil)
2655 @end lisp
2656
2657 @node Escape sequences in shell output
2658 @section Why these strange escape sequences from @code{ls} from the Shell mode?
2659 @cindex Escape sequences in @code{ls} output
2660 @cindex @code{ls} in Shell mode
2661
2662 In many systems, @code{ls} is aliased to @samp{ls --color}, which
2663 prints using ANSI color escape sequences. Emacs version 21.1 and
2664 later includes the @code{ansi-color} package, which lets Shell mode
2665 recognize these escape sequences. In Emacs 23.2 and later, the
2666 package is enabled by default; in earlier versions you can enable it
2667 by typing @kbd{M-x ansi-color-for-comint-mode} in the Shell buffer, or
2668 by adding @code{(add-hook 'shell-mode-hook
2669 'ansi-color-for-comint-mode-on)} to your init file.
2670
2671 In Emacs versions before 21.1, the @code{ansi-color} package is not
2672 included. In that case, you need to unalias @code{ls} for interactive
2673 shells running in Emacs; this can be done by checking the @code{EMACS}
2674 variable in the environment.
2675
2676 @node Fullscreen mode on MS-Windows
2677 @section How can I start Emacs in fullscreen mode on MS-Windows?
2678 @cindex Maximize frame
2679 @cindex Fullscreen mode
2680
2681 Use the function @code{w32-send-sys-command}. For example, you can
2682 put the following in your @file{.emacs} file:
2683
2684 @lisp
2685 (add-hook 'emacs-startup-hook
2686 (lambda () (w32-send-sys-command ?\xF030)))
2687 @end lisp
2688
2689 To avoid the slightly distracting visual effect of Emacs starting with
2690 its default frame size and then growing to fullscreen, you can add an
2691 @samp{Emacs.Geometry} entry to the Windows registry settings.
2692 @xref{X Resources,,, emacs, The GNU Emacs Manual}.
2693
2694 To compute the correct values for width and height, first maximize the
2695 Emacs frame and then evaluate @code{(frame-height)} and
2696 @code{(frame-width)} with @kbd{M-:}.
2697
2698 @c ------------------------------------------------------------
2699 @node Bugs and problems
2700 @chapter Bugs and problems
2701 @cindex Bugs and problems
2702
2703 The Emacs manual lists some common kinds of trouble users could get
2704 into, see @ref{Lossage, , Dealing with Emacs Trouble, emacs, The GNU
2705 Emacs Manual}, so you might look there if the problem you encounter
2706 isn't described in this chapter. If you decide you've discovered a bug,
2707 see @ref{Bugs, , Reporting Bugs, emacs, The GNU Emacs Manual}, for
2708 instructions how to do that.
2709
2710 The file @file{etc/PROBLEMS} in the Emacs distribution lists various
2711 known problems with building and using Emacs on specific platforms;
2712 type @kbd{C-h C-p} to read it.
2713
2714 @menu
2715 * Problems with very large files::
2716 * ^M in the shell buffer::
2717 * Problems with Shell Mode::
2718 * Termcap/Terminfo entries for Emacs::
2719 * Errors with init files::
2720 * Emacs ignores X resources::
2721 * Emacs ignores frame parameters::
2722 * Editing files with $ in the name::
2723 * Shell mode loses the current directory::
2724 * Security risks with Emacs::
2725 * Dired claims that no file is on this line::
2726 @end menu
2727
2728 @node Problems with very large files
2729 @section Does Emacs have problems with files larger than 8 megabytes?
2730 @cindex Very large files, opening
2731 @cindex Large files, opening
2732 @cindex Opening very large files
2733 @cindex Maximum file size
2734 @cindex Files, maximum size
2735
2736 Old versions (i.e., anything before 19.29) of Emacs had problems editing
2737 files larger than 8 megabytes. In versions 19.29 and later, the maximum
2738 buffer size is at least @math{2^{27}-1}, or 134,217,727 bytes, or 132 MBytes.
2739 The maximum buffer size on 32-bit machines increased to 256 MBytes in
2740 Emacs 22, and again to 512 MBytes in Emacs 23.2.
2741
2742 Emacs compiled on a 64-bit machine can handle much larger buffers.
2743
2744 @node ^M in the shell buffer
2745 @section How do I get rid of @samp{^M} or echoed commands in my shell buffer?
2746 @cindex Shell buffer, echoed commands and @samp{^M} in
2747 @cindex Echoed commands in @code{shell-mode}
2748
2749 Try typing @kbd{M-x shell-strip-ctrl-m @key{RET}} while in @code{shell-mode} to
2750 make them go away. If that doesn't work, you have several options:
2751
2752 For @code{tcsh}, put this in your @file{.cshrc} (or @file{.tcshrc})
2753 file:
2754
2755 @example
2756 if ($?EMACS) then
2757 if ("$EMACS" =~ /*) then
2758 if ($?tcsh) unset edit
2759 stty nl
2760 endif
2761 endif
2762 @end example
2763
2764 Or put this in your @file{.emacs_tcsh} or @file{~/.emacs.d/init_tcsh.sh} file:
2765
2766 @example
2767 unset edit
2768 stty nl
2769 @end example
2770
2771 Alternatively, use @code{csh} in your shell buffers instead of
2772 @code{tcsh}. One way is:
2773
2774 @lisp
2775 (setq explicit-shell-file-name "/bin/csh")
2776 @end lisp
2777
2778 @noindent
2779 and another is to do this in your @file{.cshrc} (or @file{.tcshrc})
2780 file:
2781
2782 @example
2783 setenv ESHELL /bin/csh
2784 @end example
2785
2786 @noindent
2787 (You must start Emacs over again with the environment variable properly
2788 set for this to take effect.)
2789
2790 You can also set the @code{ESHELL} environment variable in Emacs Lisp
2791 with the following Lisp form,
2792
2793 @lisp
2794 (setenv "ESHELL" "/bin/csh")
2795 @end lisp
2796
2797 The above solutions try to prevent the shell from producing the
2798 @samp{^M} characters in the first place. If this is not possible
2799 (e.g., if you use a Windows shell), you can get Emacs to remove these
2800 characters from the buffer by adding this to your @file{.emacs} init
2801 file:
2802
2803 @smalllisp
2804 (add-hook 'comint-output-filter-functions 'shell-strip-ctrl-m)
2805 @end smalllisp
2806
2807 On a related note: if your shell is echoing your input line in the shell
2808 buffer, you might want to customize the @code{comint-process-echoes}
2809 variable in your shell buffers, or try the following command in your
2810 shell start-up file:
2811
2812 @example
2813 stty -icrnl -onlcr -echo susp ^Z
2814 @end example
2815
2816 @node Problems with Shell Mode
2817 @section Why do I get an error message when I try to run @kbd{M-x shell}?
2818
2819 @cindex Shell Mode, problems
2820 @cindex @code{explicit-shell-file-name}
2821 This might happen because Emacs tries to look for the shell in a wrong
2822 place. If you know where your shell executable is, set the variable
2823 @code{explicit-shell-file-name} in your @file{.emacs} file to point to
2824 its full file name.
2825
2826 @cindex Antivirus programs, and Shell Mode
2827 Some people have trouble with Shell Mode on MS-Windows because of
2828 intrusive antivirus software; disabling the resident antivirus program
2829 solves the problems in those cases.
2830
2831 @node Termcap/Terminfo entries for Emacs
2832 @section Where is the termcap/terminfo entry for terminal type @samp{emacs}?
2833 @cindex Termcap
2834 @cindex Terminfo
2835 @cindex Emacs entries for termcap/terminfo
2836
2837 The termcap entry for terminal type @samp{emacs} is ordinarily put in
2838 the @samp{TERMCAP} environment variable of subshells. It may help in
2839 certain situations (e.g., using rlogin from shell buffer) to add an
2840 entry for @samp{emacs} to the system-wide termcap file. Here is a
2841 correct termcap entry for @samp{emacs}:
2842
2843 @example
2844 emacs:tc=unknown:
2845 @end example
2846
2847 To make a terminfo entry for @samp{emacs}, use @code{tic} or
2848 @code{captoinfo}. You need to generate
2849 @file{/usr/lib/terminfo/e/emacs}. It may work to simply copy
2850 @file{/usr/lib/terminfo/d/dumb} to @file{/usr/lib/terminfo/e/emacs}.
2851
2852 Having a termcap/terminfo entry will not enable the use of full screen
2853 programs in shell buffers. Use @kbd{M-x term} for that instead.
2854
2855 A workaround to the problem of missing termcap/terminfo entries is to
2856 change terminal type @samp{emacs} to type @samp{dumb} or @samp{unknown}
2857 in your shell start up file. @code{csh} users could put this in their
2858 @file{.cshrc} files:
2859
2860 @example
2861 if ("$term" == emacs) set term=dumb
2862 @end example
2863
2864 @node Errors with init files
2865 @section Why does Emacs say @samp{Error in init file}?
2866 @cindex Error in @file{.emacs}
2867 @cindex Error in init file
2868 @cindex Init file, errors in
2869 @cindex @file{.emacs} file, errors in
2870 @cindex Debugging @file{.emacs} file
2871
2872 An error occurred while loading either your @file{.emacs} file or the
2873 system-wide file @file{site-lisp/default.el}. Emacs 21.1 and later pops the
2874 @file{*Messages*} buffer, and puts there some additional information
2875 about the error, to provide some hints for debugging.
2876
2877 For information on how to debug your @file{.emacs} file, see
2878 @ref{Debugging a customization file}.
2879
2880 It may be the case that you need to load some package first, or use a
2881 hook that will be evaluated after the package is loaded. A common case
2882 of this is explained in @ref{Terminal setup code works after Emacs has
2883 begun}.
2884
2885 @node Emacs ignores X resources
2886 @section Why does Emacs ignore my X resources (my .Xdefaults file)?
2887 @cindex X resources being ignored
2888 @cindex Ignored X resources
2889 @cindex @file{.Xdefaults}
2890
2891 As of version 19, Emacs searches for X resources in the files specified
2892 by the following environment variables:
2893
2894 @itemize @bullet
2895
2896 @item @code{XFILESEARCHPATH}
2897 @item @code{XUSERFILESEARCHPATH}
2898 @item @code{XAPPLRESDIR}
2899
2900 @end itemize
2901
2902 This emulates the functionality provided by programs written using the
2903 Xt toolkit.
2904
2905 @code{XFILESEARCHPATH} and @code{XUSERFILESEARCHPATH} should be a list
2906 of file names separated by colons. @code{XAPPLRESDIR} should be a list
2907 of directory names separated by colons.
2908
2909 Emacs searches for X resources:
2910
2911 @enumerate
2912
2913 @item
2914 specified on the command line, with the @samp{-xrm RESOURCESTRING} option,
2915
2916 @item
2917 then in the value of the @samp{XENVIRONMENT} environment variable,
2918
2919 @itemize @minus
2920
2921 @item
2922 or if that is unset, in the file named
2923 @file{~/.Xdefaults-@var{hostname}} if it exists (where @var{hostname} is
2924 the name of the machine Emacs is running on),
2925
2926 @end itemize
2927
2928 @item
2929 then in the screen-specific and server-wide resource properties provided
2930 by the server,
2931
2932 @itemize @minus
2933
2934 @item
2935 or if those properties are unset, in the file named @file{~/.Xdefaults}
2936 if it exists,
2937
2938 @end itemize
2939
2940 @item
2941 then in the files listed in @samp{XUSERFILESEARCHPATH},
2942
2943 @itemize @minus
2944
2945 @item
2946 or in files named @file{@var{lang}/Emacs} in directories listed in
2947 @samp{XAPPLRESDIR} (where @var{lang} is the value of the @code{LANG}
2948 environment variable), if the @samp{LANG} environment variable is set,
2949 @item
2950 or in files named Emacs in the directories listed in @samp{XAPPLRESDIR}
2951 @item
2952 or in @file{~/@var{lang}/Emacs} (if the @code{LANG} environment variable
2953 is set),
2954 @item
2955 or in @file{~/Emacs},
2956
2957 @end itemize
2958
2959 @item
2960 then in the files listed in @code{XFILESEARCHPATH}.
2961
2962 @end enumerate
2963
2964 @node Emacs ignores frame parameters
2965 @section Why don't my customizations of the frame parameters work?
2966 @cindex Frame parameters
2967
2968 This probably happens because you have set the frame parameters in the
2969 variable @code{initial-frame-alist}. That variable holds parameters
2970 used only for the first frame created when Emacs starts. To customize
2971 the parameters of all frames, change the variable
2972 @code{default-frame-alist} instead.
2973
2974 These two variables exist because many users customize the initial frame
2975 in a special way. For example, you could determine the position and
2976 size of the initial frame, but would like to control the geometry of the
2977 other frames by individually positioning each one of them.
2978
2979
2980 @node Editing files with $ in the name
2981 @section How do I edit a file with a @samp{$} in its name?
2982 @cindex Editing files with @samp{$} in the name
2983 @cindex @samp{$} in file names
2984 @cindex File names containing @samp{$}, editing
2985
2986 When entering a file name in the minibuffer, Emacs will attempt to expand
2987 a @samp{$} followed by a word as an environment variable. To suppress
2988 this behavior, type @kbd{$$} instead.
2989
2990 @node Shell mode loses the current directory
2991 @section Why does shell mode lose track of the shell's current directory?
2992 @cindex Current directory and @code{shell-mode}
2993 @cindex @code{shell-mode} and current directory
2994 @cindex Directory, current in @code{shell-mode}
2995
2996 Emacs has no way of knowing when the shell actually changes its
2997 directory. This is an intrinsic limitation of Unix. So it tries to
2998 guess by recognizing @samp{cd} commands. If you type @kbd{cd} followed
2999 by a directory name with a variable reference (@kbd{cd $HOME/bin}) or
3000 with a shell metacharacter (@kbd{cd ../lib*}), Emacs will fail to
3001 correctly guess the shell's new current directory. A huge variety of
3002 fixes and enhancements to shell mode for this problem have been written
3003 to handle this problem (@pxref{Finding a package with particular
3004 functionality}).
3005
3006 You can tell Emacs the shell's current directory with the command
3007 @kbd{M-x dirs}.
3008
3009 @node Security risks with Emacs
3010 @section Are there any security risks in Emacs?
3011 @cindex Security with Emacs
3012 @cindex @samp{movemail} and security
3013 @cindex @code{file-local-variable} and security
3014 @cindex Synthetic X events and security
3015 @cindex X events and security
3016
3017 @itemize @bullet
3018
3019 @item
3020 The @file{movemail} incident. (No, this is not a risk.)
3021
3022 In his book @cite{The Cuckoo's Egg}, Cliff Stoll describes this in
3023 chapter 4. The site at LBL had installed the @file{/etc/movemail}
3024 program setuid root. (As of version 19, @file{movemail} is in your
3025 architecture-specific directory; type @kbd{C-h v exec-directory
3026 @key{RET}} to see what it is.) Since @code{movemail} had not been
3027 designed for this situation, a security hole was created and users could
3028 get root privileges.
3029
3030 @code{movemail} has since been changed so that this security hole will
3031 not exist, even if it is installed setuid root. However,
3032 @code{movemail} no longer needs to be installed setuid root, which
3033 should eliminate this particular risk.
3034
3035 We have heard unverified reports that the 1988 Internet worm took
3036 advantage of this configuration problem.
3037
3038 @item
3039 The @code{file-local-variable} feature. (Yes, a risk, but easy to
3040 change.)
3041
3042 There is an Emacs feature that allows the setting of local values for
3043 variables when editing a file by including specially formatted text near
3044 the end of the file. This feature also includes the ability to have
3045 arbitrary Emacs Lisp code evaluated when the file is visited.
3046 Obviously, there is a potential for Trojan horses to exploit this
3047 feature.
3048
3049 As of Emacs 22, Emacs has a list of local variables that are known to
3050 be safe to set. If a file tries to set any variable outside this
3051 list, it asks the user to confirm whether the variables should be set.
3052 You can also tell Emacs whether to allow the evaluation of Emacs Lisp
3053 code found at the bottom of files by setting the variable
3054 @code{enable-local-eval}.
3055
3056 @xref{File Variables,,, emacs, The GNU Emacs Manual}.
3057
3058 @item
3059 Synthetic X events. (Yes, a risk; use @samp{MIT-MAGIC-COOKIE-1} or
3060 better.)
3061
3062 Emacs accepts synthetic X events generated by the @code{SendEvent}
3063 request as though they were regular events. As a result, if you are
3064 using the trivial host-based authentication, other users who can open X
3065 connections to your X workstation can make your Emacs process do
3066 anything, including run other processes with your privileges.
3067
3068 The only fix for this is to prevent other users from being able to open
3069 X connections. The standard way to prevent this is to use a real
3070 authentication mechanism, such as @samp{MIT-MAGIC-COOKIE-1}. If using
3071 the @code{xauth} program has any effect, then you are probably using
3072 @samp{MIT-MAGIC-COOKIE-1}. Your site may be using a superior
3073 authentication method; ask your system administrator.
3074
3075 If real authentication is not a possibility, you may be satisfied by
3076 just allowing hosts access for brief intervals while you start your X
3077 programs, then removing the access. This reduces the risk somewhat by
3078 narrowing the time window when hostile users would have access, but
3079 @emph{does not eliminate the risk}.
3080
3081 On most computers running Unix and X, you enable and disable
3082 access using the @code{xhost} command. To allow all hosts access to
3083 your X server, use
3084
3085 @example
3086 xhost +
3087 @end example
3088
3089 @noindent
3090 at the shell prompt, which (on an HP machine, at least) produces the
3091 following message:
3092
3093 @example
3094 access control disabled, clients can connect from any host
3095 @end example
3096
3097 To deny all hosts access to your X server (except those explicitly
3098 allowed by name), use
3099
3100 @example
3101 xhost -
3102 @end example
3103
3104 On the test HP computer, this command generated the following message:
3105
3106 @example
3107 access control enabled, only authorized clients can connect
3108 @end example
3109
3110 @end itemize
3111
3112 @node Dired claims that no file is on this line
3113 @section Dired says, @samp{no file on this line} when I try to do something.
3114 @cindex Dired does not see a file
3115
3116 Dired uses a regular expression to find the beginning of a file name.
3117 In a long Unix-style directory listing (@samp{ls -l}), the file name
3118 starts after the date. The regexp has thus been written to look for the
3119 date. By default, it should understand dates and times regardless of
3120 the language, but if your directory listing has an unusual format, Dired
3121 may get confused.
3122
3123 There are two approaches to solving this. The first one involves
3124 setting things up so that @samp{ls -l} outputs a more standard format.
3125 See your OS manual for more information.
3126
3127 The second approach involves changing the regular expression used by
3128 dired, @code{directory-listing-before-filename-regexp}.
3129
3130 @c ------------------------------------------------------------
3131 @node Compiling and installing Emacs
3132 @chapter Compiling and installing Emacs
3133 @cindex Compiling and installing Emacs
3134
3135 @menu
3136 * Installing Emacs::
3137 * Problems building Emacs::
3138 @end menu
3139
3140 @node Installing Emacs
3141 @section How do I install Emacs?
3142 @cindex Installing Emacs
3143 @cindex Unix systems, installing Emacs on
3144 @cindex Downloading and installing Emacs
3145 @cindex Building Emacs from source
3146 @cindex Source code, building Emacs from
3147
3148 This answer is meant for users of Unix and Unix-like systems. Users of
3149 other operating systems should see the series of questions beginning
3150 with @ref{Emacs for MS-DOS}, which describe where to get non-Unix source
3151 and binaries, and how to install Emacs on those systems.
3152
3153 Most GNU/Linux distributions provide pre-built Emacs packages.
3154 If Emacs is not installed already, you can install it by running (as
3155 root) a command such as @samp{yum install emacs} (Red Hat and
3156 derivatives) or @samp{apt-get install emacs} (Debian and derivatives).
3157
3158 If you want to compile Emacs yourself, read the file @file{INSTALL} in
3159 the source distribution. In brief:
3160
3161 @itemize @bullet
3162
3163 @item
3164 First download the Emacs sources. @xref{Current GNU distributions}, for
3165 a list of ftp sites that make them available. On @file{ftp.gnu.org},
3166 the main GNU distribution site, sources are available as
3167
3168 @c Don't include VER in the file name, because pretests are not there.
3169 @uref{ftp://ftp.gnu.org/pub/gnu/emacs/emacs-VERSION.tar.gz}
3170
3171 (Replace @samp{VERSION} with the relevant version number, e.g., @samp{23.1}.)
3172
3173 @item
3174 Next uncompress and extract the source files. This requires
3175 the @code{gzip} and @code{tar} programs, which are standard utilities.
3176 If your system does not have them, these can also be downloaded from
3177 @file{ftp.gnu.org}.
3178
3179 GNU @code{tar} can uncompress and extract in a single-step:
3180
3181 @example
3182 tar -zxvf emacs-VERSION.tar.gz
3183 @end example
3184
3185 @item
3186 At this point, the Emacs sources should be sitting in a directory called
3187 @file{emacs-VERSION}. On most common Unix and Unix-like systems,
3188 you should be able to compile Emacs with the following commands:
3189
3190 @example
3191 cd emacs-VERSION
3192 ./configure # configure Emacs for your particular system
3193 make # use Makefile to build components, then Emacs
3194 @end example
3195
3196 If the @code{make} completes successfully, the odds are fairly good that
3197 the build has gone well. (@xref{Problems building Emacs}, if you weren't
3198 successful.)
3199
3200 @item
3201 By default, Emacs is installed in @file{/usr/local}. To actually
3202 install files, become the superuser and type
3203
3204 @example
3205 make install
3206 @end example
3207
3208 Note that @samp{make install} will overwrite @file{/usr/local/bin/emacs}
3209 and any Emacs Info files that might be in @file{/usr/local/share/info/}.
3210
3211 @end itemize
3212
3213 @node Problems building Emacs
3214 @section What should I do if I have trouble building Emacs?
3215 @cindex Problems building Emacs
3216 @cindex Errors when building Emacs
3217
3218 First look in the file @file{etc/PROBLEMS} (where you unpack the Emacs
3219 source) to see if there is already a solution for your problem. Next,
3220 look for other questions in this FAQ that have to do with Emacs
3221 installation and compilation problems.
3222
3223 If you'd like to have someone look at your problem and help solve it,
3224 see @ref{Help installing Emacs}.
3225
3226 If you cannot find a solution in the documentation, please report the
3227 problem (@pxref{Reporting bugs}).
3228
3229
3230 @c ------------------------------------------------------------
3231 @node Finding Emacs and related packages
3232 @chapter Finding Emacs and related packages
3233 @cindex Finding Emacs and related packages
3234
3235 @menu
3236 * Finding Emacs on the Internet::
3237 * Finding a package with particular functionality::
3238 * Packages that do not come with Emacs::
3239 * Spell-checkers::
3240 * Current GNU distributions::
3241 * Difference between Emacs and XEmacs::
3242 * Emacs for minimalists::
3243 * Emacs for MS-DOS::
3244 * Emacs for MS-Windows::
3245 * Emacs for GNUstep::
3246 * Emacs for Mac OS X::
3247 @end menu
3248
3249 @node Finding Emacs on the Internet
3250 @section Where can I get Emacs on the net?
3251 @cindex Finding Emacs on the Internet
3252 @cindex Downloading Emacs
3253
3254 Information on downloading Emacs is available at
3255 @uref{http://www.gnu.org/software/emacs/, the Emacs home-page}.
3256
3257 @xref{Installing Emacs}, for information on how to obtain and build the latest
3258 version of Emacs, and see @ref{Current GNU distributions}, for a list of
3259 archive sites that make GNU software available.
3260
3261 @node Finding a package with particular functionality
3262 @section How do I find a Emacs Lisp package that does XXX?
3263 @cindex Package, finding
3264 @cindex Finding an Emacs Lisp package
3265 @cindex Functionality, finding a particular package
3266
3267 First of all, you should check to make sure that the package isn't
3268 already available. For example, typing @kbd{M-x apropos @key{RET}
3269 python @key{RET}} lists all functions and variables containing the
3270 string @samp{python}.
3271
3272 It is also possible that the package is on your system, but has not been
3273 loaded. To see which packages are available for loading, look through
3274 your computer's lisp directory (@pxref{File-name conventions}). The Lisp
3275 source to most packages contains a short description of how they
3276 should be loaded, invoked, and configured---so before you use or
3277 modify a Lisp package, see if the author has provided any hints in the
3278 source code.
3279
3280 The command @kbd{C-h p} (@code{finder-by-keyword}) allows you to browse
3281 the constituent Emacs packages.
3282
3283 For advice on how to find extra packages that are not part of Emacs,
3284 see @ref{Packages that do not come with Emacs}.
3285
3286 @c Note that M-x view-external-packages references this node.
3287 @node Packages that do not come with Emacs
3288 @section Where can I get Emacs Lisp packages that don't come with Emacs?
3289 @cindex Unbundled packages
3290 @cindex Finding other packages
3291 @cindex Lisp packages that do not come with Emacs
3292 @cindex Packages, those that do not come with Emacs
3293 @cindex Emacs Lisp List
3294 @cindex Emacs Lisp Archive
3295
3296 The easiest way to add more features to your Emacs is to use the
3297 command @kbd{M-x list-packages}. This contacts the
3298 @uref{http:///elpa.gnu.org, GNU ELPA} (``Emacs Lisp Package Archive'')
3299 server and fetches the list of additional packages that it offers.
3300 These are GNU packages that are available for use with Emacs, but are
3301 distributed separately from Emacs itself, for reasons of space, etc.
3302 You can browse the resulting @file{*Packages*} buffer to see what is
3303 available, and then Emacs can automatically download and install the
3304 packages that you select. @xref{Packages,,, emacs, The GNU Emacs Manual}.
3305
3306 There are other, non-GNU, Emacs Lisp package servers, including:
3307 @uref{http://melpa.milkbox.net, MELPA}; and
3308 @uref{http://marmalade-repo.org, Marmalade}. To use additional
3309 package servers, customize the @code{package-archives} variable.
3310 Be aware that installing a package can run arbitrary code, so only add
3311 sources that you trust.
3312
3313 The @uref{https://lists.gnu.org/mailman/listinfo/gnu-emacs-sources,
3314 GNU Emacs sources mailing list}, which is gatewayed to the
3315 @uref{news:gnu.emacs.sources, Emacs sources newsgroup} (although the
3316 connection between the two can be unreliable) is an official place
3317 where people can post or announce their extensions to Emacs.
3318
3319 The @uref{http://emacswiki.org, Emacs Wiki} contains pointers to some
3320 additional extensions. @uref{http://wikemacs.org, WikEmacs} is an
3321 alternative wiki for Emacs.
3322
3323 @uref{http://www.damtp.cam.ac.uk/user/sje30/emacs/ell.html, The Emacs
3324 Lisp List (ELL)}, has pointers to many Emacs Lisp files, but at time
3325 of writing it is no longer being updated.
3326
3327 It is impossible for us to list here all the sites that offer Emacs
3328 Lisp packages. If you are interested in a specific feature, then
3329 after checking Emacs itself and GNU ELPA, a web search is often the
3330 best way to find results.
3331
3332 @node Spell-checkers
3333 @section Spell-checkers
3334 @cindex Spell-checker
3335 @cindex Checking spelling
3336 @cindex Ispell
3337 @cindex Aspell
3338 @cindex Hunspell
3339
3340 Various spell-checkers are compatible with Emacs, including:
3341
3342 @table @b
3343
3344 @item GNU Aspell
3345 @uref{http://aspell.net/}
3346
3347 @item Ispell
3348 @uref{http://fmg-www.cs.ucla.edu/geoff/ispell.html}
3349
3350 @item Hunspell
3351 @uref{http://hunspell.sourceforge.net/}
3352
3353 @end table
3354
3355 @node Current GNU distributions
3356 @section Where can I get other up-to-date GNU stuff?
3357 @cindex Current GNU distributions
3358 @cindex Sources for current GNU distributions
3359 @cindex Stuff, current GNU
3360 @cindex Up-to-date GNU stuff
3361 @cindex Finding current GNU software
3362 @cindex Official GNU software sites
3363
3364 The most up-to-date official GNU software is normally kept at
3365
3366 @uref{ftp://ftp.gnu.org/pub/gnu}
3367
3368 A list of sites mirroring @samp{ftp.gnu.org} can be found at
3369
3370 @uref{http://www.gnu.org/order/ftp.html}
3371
3372 @node Difference between Emacs and XEmacs
3373 @section What is the difference between Emacs and XEmacs (formerly Lucid Emacs)?
3374 @cindex XEmacs
3375 @cindex Difference Emacs and XEmacs
3376 @cindex Lucid Emacs
3377 @cindex Epoch
3378
3379 XEmacs is a branch version of Emacs. It was first called Lucid Emacs,
3380 and was initially derived from a prerelease version of Emacs 19. In
3381 this FAQ, we use the name ``Emacs'' only for the official version.
3382
3383 Emacs and XEmacs each come with Lisp packages that are lacking in the
3384 other. The two versions have some significant differences at the Lisp
3385 programming level. Their current features are roughly comparable,
3386 though the support for some operating systems, character sets and
3387 specific packages might be quite different.
3388
3389 Some XEmacs code has been contributed to Emacs, and we would like to
3390 use other parts, but the earlier XEmacs maintainers did not always
3391 keep track of the authors of contributed code, which makes it
3392 impossible for the FSF to get copyright papers signed for that code.
3393 (The FSF requires these papers for all the code included in the Emacs
3394 release, aside from generic C support packages that retain their
3395 separate identity and are not integrated into the code of Emacs
3396 proper.)
3397
3398 If you want to talk about these two versions and distinguish them,
3399 please call them ``Emacs'' and ``XEmacs.'' To contrast ``XEmacs''
3400 with ``GNU Emacs'' would be misleading, since XEmacs too has its
3401 origin in the work of the GNU Project. Terms such as ``Emacsen'' and
3402 ``(X)Emacs'' are not wrong, but they are not very clear, so it
3403 is better to write ``Emacs and XEmacs.''
3404
3405 @node Emacs for minimalists
3406 @section I don't have enough disk space to install Emacs
3407 @cindex Zile
3408 @cindex Not enough disk space to install Emacs
3409
3410 GNU Zile is a lightweight Emacs clone. Zile is short for @samp{Zile Is
3411 Lossy Emacs}. It has all of Emacs's basic editing features. The Zile
3412 binary typically has a size of about 130 kbytes, so this can be useful
3413 if you are in an extremely space-restricted environment. More
3414 information is available from
3415
3416 @uref{http://www.gnu.org/software/zile/}
3417
3418
3419 @node Emacs for MS-DOS
3420 @section Where can I get Emacs for MS-DOS?
3421 @cindex MS-DOS, Emacs for
3422 @cindex DOS, Emacs for
3423 @cindex Compiling Emacs for DOS
3424 @cindex Emacs for MS-DOS
3425
3426 To build Emacs from source for MS-DOS, see the instructions in the file
3427 @file{msdos/INSTALL} in the distribution. The DOS port builds and runs
3428 on plain DOS, and also on all versions of MS-Windows from version 3.X
3429 onwards, including Windows XP and Vista.
3430
3431 The file @file{etc/PROBLEMS} contains some additional information
3432 regarding Emacs under MS-DOS.
3433
3434 A pre-built binary distribution of the old Emacs 20 is available, as
3435 described at
3436
3437 @uref{ftp://ftp.delorie.com/pub/djgpp/current/v2gnu/emacs.README}
3438
3439 For a list of other MS-DOS implementations of Emacs (and Emacs
3440 look-alikes), consult the list of ``Emacs implementations and literature,''
3441 available at
3442
3443 @uref{http://www.finseth.com/emacs.html}
3444
3445 Note that while many of these programs look similar to Emacs, they often
3446 lack certain features, such as the Emacs Lisp extension language.
3447
3448 @node Emacs for MS-Windows
3449 @section Where can I get Emacs for Microsoft Windows?
3450 @cindex FAQ for Emacs on MS-Windows
3451 @cindex Emacs for MS-Windows
3452 @cindex Microsoft Windows, Emacs for
3453
3454 There is a separate FAQ for Emacs on MS-Windows,
3455 @pxref{Top,,,efaq-w32,FAQ for Emacs on MS Windows}.
3456 For MS-DOS, @pxref{Emacs for MS-DOS}.
3457
3458
3459 @node Emacs for GNUstep
3460 @section Where can I get Emacs for GNUstep?
3461 @cindex GNUstep, Emacs for
3462
3463 Beginning with version 23.1, Emacs supports GNUstep natively.
3464 See the file @file{nextstep/INSTALL} in the distribution.
3465
3466 @node Emacs for Mac OS X
3467 @section Where can I get Emacs for Mac OS X?
3468 @cindex Apple computers, Emacs for
3469 @cindex Macintosh, Emacs for
3470 @cindex Mac OS X, Emacs for
3471
3472 Beginning with version 22.1, Emacs supports Mac OS X natively.
3473 See the file @file{nextstep/INSTALL} in the distribution.
3474
3475 @c ------------------------------------------------------------
3476 @node Key bindings
3477 @chapter Key bindings
3478 @cindex Key bindings
3479
3480 @menu
3481 * Binding keys to commands::
3482 * Invalid prefix characters::
3483 * Terminal setup code works after Emacs has begun::
3484 * Working with function and arrow keys::
3485 * X key translations for Emacs::
3486 * Backspace invokes help::
3487 * Swapping keys::
3488 * Producing C-XXX with the keyboard::
3489 * No Meta key::
3490 * No Escape key::
3491 * Compose Character::
3492 * Binding combinations of modifiers and function keys::
3493 * Meta key does not work in xterm::
3494 * ExtendChar key does not work as Meta::
3495 * SPC no longer completes file names::
3496 @end menu
3497
3498 @node Binding keys to commands
3499 @section How do I bind keys (including function keys) to commands?
3500 @cindex Binding keys to commands
3501 @cindex Keys, binding to commands
3502 @cindex Commands, binding keys to
3503
3504 Keys can be bound to commands either interactively or in your
3505 @file{.emacs} file. To interactively bind keys for all modes, type
3506 @kbd{M-x global-set-key @key{RET} @var{key} @var{cmd} @key{RET}}.
3507
3508 To bind a key just in the current major mode, type @kbd{M-x
3509 local-set-key @key{RET} @var{key} @var{cmd} @key{RET}}.
3510
3511 @xref{Key Bindings,,, emacs, The GNU Emacs Manual}.
3512
3513 To make the process of binding keys interactively easier, use the
3514 following ``trick'': First bind the key interactively, then immediately
3515 type @kbd{C-x @key{ESC} @key{ESC} C-a C-k C-g}. Now, the command needed
3516 to bind the key is in the kill ring, and can be yanked into your
3517 @file{.emacs} file. If the key binding is global, no changes to the
3518 command are required. For example,
3519
3520 @lisp
3521 (global-set-key (quote [f1]) (quote help-for-help))
3522 @end lisp
3523
3524 @noindent
3525 can be placed directly into the @file{.emacs} file. If the key binding is
3526 local, the command is used in conjunction with the @samp{add-hook} function.
3527 For example, in TeX mode, a local binding might be
3528
3529 @lisp
3530 (add-hook 'tex-mode-hook
3531 (lambda ()
3532 (local-set-key (quote [f1]) (quote help-for-help))))
3533 @end lisp
3534
3535
3536 @itemize @bullet
3537
3538 @item
3539 Control characters in key sequences, in the form yanked from the kill
3540 ring are given in their graphic form---i.e., @key{CTRL} is shown as
3541 @samp{^}, @key{TAB} as a set of spaces (usually 8), etc. You may want
3542 to convert these into their vector or string forms.
3543
3544 @item
3545 If a prefix key of the character sequence to be bound is already
3546 bound as a complete key, then you must unbind it before the new
3547 binding. For example, if @kbd{ESC @{} is previously bound:
3548
3549 @lisp
3550 (global-unset-key [?\e ?@{]) ;; or
3551 (local-unset-key [?\e ?@{])
3552 @end lisp
3553
3554 @item
3555 Aside from commands and ``lambda lists,'' a vector or string also
3556 can be bound to a key and thus treated as a macro. For example:
3557
3558 @lisp
3559 (global-set-key [f10] [?\C-x?\e?\e?\C-a?\C-k?\C-g]) ;; or
3560 (global-set-key [f10] "\C-x\e\e\C-a\C-k\C-g")
3561 @end lisp
3562
3563 @end itemize
3564
3565 @node Invalid prefix characters
3566 @section Why does Emacs say @samp{Key sequence XXX uses invalid prefix characters}?
3567 @cindex Prefix characters, invalid
3568 @cindex Invalid prefix characters
3569 @cindex Misspecified key sequences
3570
3571 Usually, one of two things has happened. In one case, the control
3572 character in the key sequence has been misspecified (e.g., @samp{C-f}
3573 used instead of @samp{\C-f} within a Lisp expression). In the other
3574 case, a @dfn{prefix key} in the keystroke sequence you were trying to bind
3575 was already bound as a @dfn{complete key}. Historically, the @samp{ESC [}
3576 prefix was usually the problem, in which case you should evaluate either
3577 of these forms before attempting to bind the key sequence:
3578
3579 @lisp
3580 (global-unset-key [?\e ?[]) ;; or
3581 (global-unset-key "\e[")
3582 @end lisp
3583
3584 @node Terminal setup code works after Emacs has begun
3585 @section Why doesn't this [terminal or window-system setup] code work in my @file{.emacs} file, but it works just fine after Emacs starts up?
3586 @cindex Terminal setup code in @file{.emacs}
3587
3588 During startup, Emacs initializes itself according to a given code/file
3589 order. If some of the code executed in your @file{.emacs} file needs to
3590 be postponed until the initial terminal or window-system setup code has
3591 been executed but is not, then you will experience this problem (this
3592 code/file execution order is not enforced after startup).
3593
3594 To postpone the execution of Emacs Lisp code until after terminal or
3595 window-system setup, treat the code as a @dfn{lambda list} and add it to
3596 @code{emacs-startup-hook} (or @code{tty-setup-hook} in Emacs 24.4 and
3597 newer). For example,
3598
3599 @lisp
3600 (add-hook 'emacs-startup-hook
3601 (lambda ()
3602 (when (string-match "\\`vt220" (or (getenv "TERM") ""))
3603 ;; Make vt220's "Do" key behave like M-x:
3604 (global-set-key [do] 'execute-extended-command))))
3605 @end lisp
3606
3607 For information on what Emacs does every time it is started, see the
3608 @file{lisp/startup.el} file.
3609
3610 @node Working with function and arrow keys
3611 @section How do I tell what characters or symbols my function or arrow keys emit?
3612 @cindex Working with arrow keys
3613 @cindex Arrow keys, symbols generated by
3614 @cindex Working with function keys
3615 @cindex Function keys, symbols generated by
3616 @cindex Symbols generated by function keys
3617
3618 Type @kbd{C-h c} then the function or arrow keys. The command will
3619 return either a function key symbol or character sequence (see the
3620 Emacs documentation for an explanation). This works for other
3621 keys as well.
3622
3623 @node X key translations for Emacs
3624 @section How do I set the X key ``translations'' for Emacs?
3625 @cindex X key translations
3626 @cindex Key translations under X
3627 @cindex Translations for keys under X
3628
3629 Emacs is not written using the Xt library by default, so there are no
3630 ``translations'' to be set. (We aren't sure how to set such translations
3631 if you do build Emacs with Xt; please let us know if you've done this!)
3632
3633 The only way to affect the behavior of keys within Emacs is through
3634 @code{xmodmap} (outside Emacs) or @code{define-key} (inside Emacs). The
3635 @code{define-key} command should be used in conjunction with the
3636 @code{function-key-map} map. For instance,
3637
3638 @lisp
3639 (define-key function-key-map [M-@key{TAB}] [?\M-\t])
3640 @end lisp
3641
3642 @noindent
3643 defines the @kbd{M-@key{TAB}} key sequence.
3644
3645 @node Backspace invokes help
3646 @section Why does the @key{Backspace} key invoke help?
3647 @cindex Backspace key invokes help
3648 @cindex Help invoked by Backspace
3649 @cindex DEL key does not delete
3650
3651 The @key{Backspace} key (on most keyboards) generates @acronym{ASCII} code 8.
3652 @kbd{C-h} sends the same code. In Emacs by default @kbd{C-h} invokes
3653 help-command. This is intended to be easy to remember since the first
3654 letter of @samp{help} is @samp{h}. The easiest solution to this problem
3655 is to use @kbd{C-h} (and @key{Backspace}) for help and @key{DEL} (the
3656 @key{Delete} key) for deleting the previous character.
3657
3658 For many people this solution may be problematic:
3659
3660 @itemize @bullet
3661
3662 @item
3663 They normally use @key{Backspace} outside of Emacs for deleting the
3664 previous character. This can be solved by making @key{DEL} the command
3665 for deleting the previous character outside of Emacs. On many Unix
3666 systems, this command will remap @key{DEL}:
3667
3668 @example
3669 stty erase `^?'
3670 @end example
3671
3672 @item
3673 The user may prefer the @key{Backspace} key for deleting the
3674 previous character because it is more conveniently located on their
3675 keyboard or because they don't even have a separate @key{Delete} key.
3676 In this case, the @key{Backspace} key should be made to behave like
3677 @key{Delete}. There are several methods.
3678
3679 @itemize @minus
3680 @item
3681 Some terminals (e.g., VT3## terminals) and terminal emulators (e.g.,
3682 TeraTerm) allow the character generated by the @key{Backspace} key to be
3683 changed from a setup menu.
3684
3685 @item
3686 You may be able to get a keyboard that is completely programmable, or a
3687 terminal emulator that supports remapping of any key to any other key.
3688
3689 @item
3690 With Emacs 21.1 and later, you can control the effect of the
3691 @key{Backspace} and @key{Delete} keys, on both dumb terminals and a
3692 windowed displays, by customizing the option
3693 @code{normal-erase-is-backspace-mode}, or by invoking @kbd{M-x
3694 normal-erase-is-backspace}. See the documentation of these symbols
3695 (@pxref{Emacs Lisp documentation}) for more info.
3696
3697 @item
3698 It is possible to swap the @key{Backspace} and @key{DEL} keys inside
3699 Emacs:
3700
3701 @lisp
3702 (keyboard-translate ?\C-h ?\C-?)
3703 @end lisp
3704
3705 @noindent
3706 This is the recommended method of forcing @key{Backspace} to act as
3707 @key{DEL}, because it works even in modes which bind @key{DEL} to
3708 something other than @code{delete-backward-char}.
3709
3710 Similarly, you could remap @key{DEL} to act as @kbd{C-d}, which by
3711 default deletes forward:
3712
3713 @lisp
3714 (keyboard-translate ?\C-? ?\C-d)
3715 @end lisp
3716
3717 @xref{Swapping keys}, for further details about @code{keyboard-translate}.
3718
3719 @item
3720 Another approach is to switch key bindings and put help on @kbd{C-x h}
3721 instead:
3722
3723 @lisp
3724 (global-set-key "\C-h" 'delete-backward-char)
3725
3726 ;; overrides mark-whole-buffer
3727 (global-set-key "\C-xh" 'help-command)
3728 @end lisp
3729
3730 @noindent
3731 This method is not recommended, though: it only solves the problem for
3732 those modes which bind @key{DEL} to @code{delete-backward-char}. Modes
3733 which bind @key{DEL} to something else, such as @code{view-mode}, will
3734 not work as you expect when you press the @key{Backspace} key. For this
3735 reason, we recommend the @code{keyboard-translate} method, shown
3736 above.
3737
3738 Other popular key bindings for help are @kbd{M-?} and @kbd{C-x ?}.
3739 @end itemize
3740
3741 Don't try to bind @key{DEL} to @code{help-command}, because there are
3742 many modes that have local bindings of @key{DEL} that will interfere.
3743
3744 @end itemize
3745
3746 When Emacs 21 or later runs on a windowed display, it binds the
3747 @key{Delete} key to a command which deletes the character at point, to
3748 make Emacs more consistent with keyboard operation on these systems.
3749
3750 For more information about troubleshooting this problem, see @ref{DEL
3751 Does Not Delete, , If @key{DEL} Fails to Delete, emacs, The GNU Emacs
3752 Manual}.
3753
3754 @node Swapping keys
3755 @section How do I swap two keys?
3756 @cindex Swapping keys
3757 @cindex Keys, swapping
3758 @cindex @code{keyboard-translate}
3759
3760 You can swap two keys (or key sequences) by using the
3761 @code{keyboard-translate} function. For example, to turn @kbd{C-h}
3762 into @key{DEL} and @key{DEL} to @kbd{C-h}, use
3763
3764 @lisp
3765 (keyboard-translate ?\C-h ?\C-?) ; translate `C-h' to DEL
3766 (keyboard-translate ?\C-? ?\C-h) ; translate DEL to `C-h'.
3767 @end lisp
3768
3769 @noindent
3770 The first key sequence of the pair after the function identifies what is
3771 produced by the keyboard; the second, what is matched for in the
3772 keymaps.
3773
3774 However, in the specific case of @kbd{C-h} and @key{DEL}, you should
3775 toggle @code{normal-erase-is-backspace-mode} instead of calling
3776 @code{keyboard-translate}.
3777 @xref{DEL Does Not Delete,,, emacs, The GNU Emacs Manual}.
3778
3779 Keyboard translations are not the same as key bindings in keymaps.
3780 Emacs contains numerous keymaps that apply in different situations, but
3781 there is only one set of keyboard translations, and it applies to every
3782 character that Emacs reads from the terminal. Keyboard translations
3783 take place at the lowest level of input processing; the keys that are
3784 looked up in keymaps contain the characters that result from keyboard
3785 translation.
3786
3787 @node Producing C-XXX with the keyboard
3788 @section How do I produce C-XXX with my keyboard?
3789 @cindex Producing control characters
3790 @cindex Generating control characters
3791 @cindex Control characters, generating
3792
3793 On terminals (but not under X), some common ``aliases'' are:
3794
3795 @table @asis
3796
3797 @item @kbd{C-2} or @kbd{C-@key{SPC}}
3798 @kbd{C-@@}
3799
3800 @item @kbd{C-6}
3801 @kbd{C-^}
3802
3803 @item @kbd{C-7} or @kbd{C-S--}
3804 @kbd{C-_}
3805
3806 @item @kbd{C-4}
3807 @kbd{C-\}
3808
3809 @item @kbd{C-5}
3810 @kbd{C-]}
3811
3812 @item @kbd{C-/}
3813 @kbd{C-?}
3814
3815 @end table
3816
3817 Often other aliases exist; use the @kbd{C-h c} command and try
3818 @key{CTRL} with all of the digits on your keyboard to see what gets
3819 generated. You can also try the @kbd{C-h w} command if you know the
3820 name of the command.
3821
3822 @node No Meta key
3823 @section What if I don't have a @key{Meta} key?
3824 @cindex No @key{Meta} key
3825 @cindex @key{Meta} key, what to do if you lack it
3826
3827 On many keyboards, the @key{Alt} key acts as @key{Meta}, so try it.
3828
3829 Instead of typing @kbd{M-a}, you can type @kbd{@key{ESC} a}. In fact,
3830 Emacs converts @kbd{M-a} internally into @kbd{@key{ESC} a} anyway
3831 (depending on the value of @code{meta-prefix-char}). Note that you
3832 press @key{Meta} and @key{a} together, but with @key{ESC}, you press
3833 @key{ESC}, release it, and then press @key{a}.
3834
3835 @node No Escape key
3836 @section What if I don't have an @key{Escape} key?
3837 @cindex No Escape key
3838 @cindex Lacking an Escape key
3839 @cindex Escape key, lacking
3840
3841 Type @kbd{C-[} instead. This should send @acronym{ASCII} code 27 just like an
3842 Escape key would. @kbd{C-3} may also work on some terminal (but not
3843 under X). For many terminals (notably DEC terminals) @key{F11}
3844 generates @key{ESC}. If not, the following form can be used to bind it:
3845
3846 @lisp
3847 ;; F11 is the documented ESC replacement on DEC terminals.
3848 (define-key function-key-map [f11] [?\e])
3849 @end lisp
3850
3851 @node Compose Character
3852 @section Can I make my @key{Compose Character} key behave like a @key{Meta} key?
3853 @cindex @key{Compose Character} key, using as @key{Meta}
3854 @cindex @key{Meta}, using @key{Compose Character} for
3855
3856 On a dumb terminal such as a VT220, no. It is rumored that certain
3857 VT220 clones could have their @key{Compose} key configured this way. If
3858 you're using X, you might be able to do this with the @code{xmodmap}
3859 command.
3860
3861 @node Binding combinations of modifiers and function keys
3862 @section How do I bind a combination of modifier key and function key?
3863 @cindex Modifiers and function keys
3864 @cindex Function keys and modifiers
3865 @cindex Binding modifiers and function keys
3866
3867 You can represent modified function keys in vector format by adding
3868 prefixes to the function key symbol. For example (from the Emacs
3869 documentation):
3870
3871 @lisp
3872 (global-set-key [?\C-x right] 'forward-page)
3873 @end lisp
3874
3875 @noindent
3876 where @samp{?\C-x} is the Lisp character constant for the character @kbd{C-x}.
3877
3878 You can use the modifier keys @key{Control}, @key{Meta}, @key{Hyper},
3879 @key{Super}, @key{Alt}, and @key{Shift} with function keys. To
3880 represent these modifiers, prepend the strings @samp{C-}, @samp{M-},
3881 @samp{H-}, @samp{s-}, @samp{A-}, and @samp{S-} to the symbol name. Here
3882 is how to make @kbd{H-M-RIGHT} move forward a word:
3883
3884 @lisp
3885 (global-set-key [H-M-right] 'forward-word)
3886 @end lisp
3887
3888 @itemize @bullet
3889
3890 @item
3891 Not all modifiers are permitted in all situations. @key{Hyper},
3892 @key{Super}, and @key{Alt} are not available on Unix character
3893 terminals. Non-@acronym{ASCII} keys and mouse events (e.g., @kbd{C-=} and
3894 @kbd{Mouse-1}) also fall under this category.
3895
3896 @end itemize
3897
3898 @xref{Binding keys to commands}, for general key binding instructions.
3899
3900 @node Meta key does not work in xterm
3901 @section Why doesn't my @key{Meta} key work in an @code{xterm} window?
3902 @cindex @key{Meta} key and @code{xterm}
3903 @cindex Xterm and @key{Meta} key
3904
3905 @xref{Unibyte Mode,, Single-Byte Character Set Support, emacs, The GNU Emacs Manual}.
3906
3907 If the advice in the Emacs manual fails, try all of these methods before
3908 asking for further help:
3909
3910 @itemize @bullet
3911
3912 @item
3913 You may have big problems using @code{mwm} as your window manager.
3914 (Does anyone know a good generic solution to allow the use of the
3915 @key{Meta} key in Emacs with @file{mwm}?)
3916
3917 @item
3918 For X11: Make sure it really is a @key{Meta} key. Use @code{xev} to
3919 find out what keysym your @key{Meta} key generates. It should be either
3920 @code{Meta_L} or @code{Meta_R}. If it isn't, use @file{xmodmap} to fix
3921 the situation. If @key{Meta} does generate @code{Meta_L} or
3922 @code{Meta_R}, but @kbd{M-x} produces a non-@acronym{ASCII} character, put this in
3923 your @file{~/.Xdefaults} file:
3924
3925 @example
3926 XTerm*eightBitInput: false
3927 XTerm*eightBitOutput: true
3928 @end example
3929
3930 @item
3931 Make sure the @code{pty} the @code{xterm} is using is passing 8 bit
3932 characters. @samp{stty -a} (or @samp{stty everything}) should show
3933 @samp{cs8} somewhere. If it shows @samp{cs7} instead, use @samp{stty
3934 cs8 -istrip} (or @samp{stty pass8}) to fix it.
3935
3936 @item
3937 If there is an @code{rlogin} connection between @code{xterm} and Emacs, the
3938 @samp{-8} argument may need to be given to rlogin to make it pass all 8 bits
3939 of every character.
3940
3941 @item
3942 If Emacs is running on Ultrix, it is reported that evaluating
3943 @code{(set-input-mode t nil)} helps.
3944
3945 @item
3946 If all else fails, you can make @code{xterm} generate @kbd{@key{ESC} W} when
3947 you type @kbd{M-W}, which is the same conversion Emacs would make if it
3948 got the @kbd{M-W} anyway. In X11R4, the following resource
3949 specification will do this:
3950
3951 @example
3952 XTerm.VT100.EightBitInput: false
3953 @end example
3954
3955 @noindent
3956 (This changes the behavior of the @code{insert-eight-bit} action.)
3957
3958 With older @code{xterm}s, you can specify this behavior with a translation:
3959
3960 @example
3961 XTerm.VT100.Translations: #override \
3962 Meta<KeyPress>: string(0x1b) insert()
3963 @end example
3964
3965 @noindent
3966 You might have to replace @samp{Meta} with @samp{Alt}.
3967
3968 @end itemize
3969
3970 @node ExtendChar key does not work as Meta
3971 @section Why doesn't my @key{ExtendChar} key work as a @key{Meta} key under HP-UX 8.0 and 9.x?
3972 @cindex @key{ExtendChar} key as @key{Meta}
3973 @cindex @key{Meta}, using @key{ExtendChar} for
3974 @cindex HP-UX, the @key{ExtendChar} key
3975
3976 This is a result of an internationalization extension in X11R4 and the
3977 fact that HP is now using this extension. Emacs assumes that the
3978 @code{XLookupString} function returns the same result regardless of the
3979 @key{Meta} key state which is no longer necessarily true. Until Emacs
3980 is fixed, the temporary kludge is to run this command after each time
3981 the X server is started but preferably before any xterm clients are:
3982
3983 @example
3984 xmodmap -e 'remove mod1 = Mode_switch'
3985 @end example
3986
3987 @c FIXME: Emacs 21 supports I18N in X11; does that mean that this bug is
3988 @c solved?
3989
3990 This will disable the use of the extra keysyms systemwide, which may be
3991 undesirable if you actually intend to use them.
3992
3993 @node SPC no longer completes file names
3994 @section Why doesn't SPC complete file names anymore?
3995 @cindex @kbd{SPC} file name completion
3996
3997 Starting with Emacs 22.1, @kbd{SPC} no longer completes file names in
3998 the minibuffer, so that file names with embedded spaces could be typed
3999 without the need to quote the spaces.
4000
4001 You can get the old behavior by binding @kbd{SPC} to
4002 @code{minibuffer-complete-word} in the minibuffer, as follows:
4003
4004 @lisp
4005 (define-key minibuffer-local-filename-completion-map (kbd "SPC")
4006 'minibuffer-complete-word)
4007
4008 (define-key minibuffer-local-must-match-filename-map (kbd "SPC")
4009 'minibuffer-complete-word)
4010 @end lisp
4011
4012 @c ------------------------------------------------------------
4013 @node Alternate character sets
4014 @chapter Alternate character sets
4015 @cindex Alternate character sets
4016
4017 @menu
4018 * Emacs does not display 8-bit characters::
4019 * Inputting eight-bit characters::
4020 * Right-to-left alphabets::
4021 * How to add fonts::
4022 @end menu
4023
4024 @node Emacs does not display 8-bit characters
4025 @section How do I make Emacs display 8-bit characters?
4026 @cindex Displaying eight-bit characters
4027 @cindex Eight-bit characters, displaying
4028
4029 @xref{Unibyte Mode,, Single-byte Character Set Support, emacs, The GNU
4030 Emacs Manual}. On a Unix, when Emacs runs on a text-only terminal
4031 display or is invoked with @samp{emacs -nw}, you typically need to use
4032 @code{set-terminal-coding-system} to tell Emacs what the terminal can
4033 display, even after setting the language environment; otherwise
4034 non-@acronym{ASCII} characters will display as @samp{?}. On other operating
4035 systems, such as MS-DOS and MS-Windows, Emacs queries the OS about the
4036 character set supported by the display, and sets up the required
4037 terminal coding system automatically.
4038
4039 @node Inputting eight-bit characters
4040 @section How do I input eight-bit characters?
4041 @cindex Entering eight-bit characters
4042 @cindex Eight-bit characters, entering
4043 @cindex Input, 8-bit characters
4044
4045 Various methods are available for input of eight-bit characters.
4046 @xref{Unibyte Mode,, Single-byte Character Set Support, emacs, The GNU
4047 Emacs Manual}. For more sophisticated methods,
4048 @pxref{Input Methods,,, emacs, The GNU Emacs Manual}.
4049
4050 @node Right-to-left alphabets
4051 @section Where is an Emacs that can handle Semitic (right-to-left) alphabets?
4052 @cindex Right-to-left alphabets
4053 @cindex Hebrew, handling with Emacs
4054 @cindex Semitic alphabets
4055 @cindex Arabic
4056 @cindex Farsi
4057 @cindex bidirectional scripts
4058
4059 Emacs supports display and editing of bidirectional scripts, such as
4060 Arabic, Farsi, and Hebrew, since version 24.1.
4061 @xref{New in Emacs 24, bidirectional display}.
4062
4063
4064 @node How to add fonts
4065 @section How do I add fonts for use with Emacs?
4066 @cindex add fonts for use with Emacs
4067 @cindex intlfonts
4068
4069 First, download and install the BDF font files and any auxiliary
4070 packages they need. The GNU Intlfonts distribution can be found on
4071 @uref{http://directory.fsf.org/localization/intlfonts.html, the GNU
4072 Software Directory Web site}.
4073
4074 Next, if you are on X Window system, issue the following two commands
4075 from the shell's prompt:
4076
4077 @example
4078 xset +fp /usr/local/share/emacs/fonts
4079 xset fp rehash
4080 @end example
4081
4082 @noindent
4083 (Modify the first command if you installed the fonts in a directory
4084 that is not @file{/usr/local/share/emacs/fonts}.) You also need to
4085 arrange for these two commands to run whenever you log in, e.g., by
4086 adding them to your window-system startup file, such as
4087 @file{~/.xsessionrc} or @file{~/.gnomerc}.
4088
4089 Now, add the following line to your @file{~/.emacs} init file:
4090
4091 @lisp
4092 (add-to-list 'bdf-directory-list "/usr/share/emacs/fonts/bdf")
4093 @end lisp
4094
4095 @noindent
4096 (Again, modify the file name if you installed the fonts elsewhere.)
4097
4098 Finally, if you wish to use the installed fonts with @code{ps-print},
4099 add the following line to your @file{~/.emacs}:
4100
4101 @lisp
4102 (setq ps-multibyte-buffer 'bdf-font-except-latin)
4103 @end lisp
4104
4105 A few additional steps are necessary for MS-Windows; they are listed
4106 below.
4107
4108 First, make sure @emph{all} the directories with BDF font files are
4109 mentioned in @code{bdf-directory-list}. On Unix and GNU/Linux
4110 systems, one normally runs @kbd{make install} to install the BDF fonts
4111 in the same directory. By contrast, Windows users typically don't run
4112 the Intlfonts installation command, but unpack the distribution in
4113 some directory, which leaves the BDF fonts in its subdirectories. For
4114 example, assume that you unpacked Intlfonts in @file{C:/Intlfonts};
4115 then you should set @code{bdf-directory-list} as follows:
4116
4117 @lisp
4118 (setq bdf-directory-list
4119 '("C:/Intlfonts/Asian"
4120 "C:/Intlfonts/Chinese" "C:/Intlfonts/Chinese.X"
4121 "C:/Intlfonts/Chinese.BIG" "C:/Intlfonts/Ethiopic"
4122 "C:/Intlfonts/European" "C:/Intlfonts/European.BIG"
4123 "C:/Intlfonts/Japanese" "C:/Intlfonts/Japanese.X"
4124 "C:/Intlfonts/Japanese.BIG" "C:/Intlfonts/Korean.X"
4125 "C:/Intlfonts/Misc"))
4126 @end lisp
4127
4128 @cindex @code{w32-bdf-filename-alist}
4129 @cindex @code{w32-find-bdf-fonts}
4130 Next, you need to set up the variable @code{w32-bdf-filename-alist} to
4131 an alist of the BDF fonts and their corresponding file names.
4132 Assuming you have set @code{bdf-directory-list} to name all the
4133 directories with the BDF font files, the following Lisp snippet will
4134 set up @code{w32-bdf-filename-alist}:
4135
4136 @lisp
4137 (setq w32-bdf-filename-alist
4138 (w32-find-bdf-fonts bdf-directory-list))
4139 @end lisp
4140
4141 Now, create fontsets for the BDF fonts:
4142
4143 @smallexample
4144 (create-fontset-from-fontset-spec
4145 "-*-fixed-medium-r-normal-*-16-*-*-*-c-*-fontset-bdf,
4146 japanese-jisx0208:-*-*-medium-r-normal-*-16-*-*-*-c-*-jisx0208.1983-*,
4147 katakana-jisx0201:-*-*-medium-r-normal-*-16-*-*-*-c-*-jisx0201*-*,
4148 latin-jisx0201:-*-*-medium-r-normal-*-16-*-*-*-c-*-jisx0201*-*,
4149 japanese-jisx0208-1978:-*-*-medium-r-normal-*-16-*-*-*-c-*-jisx0208.1978-*,
4150 thai-tis620:-misc-fixed-medium-r-normal--16-160-72-72-m-80-tis620.2529-1,
4151 lao:-misc-fixed-medium-r-normal--16-160-72-72-m-80-MuleLao-1,
4152 tibetan-1-column:-TibMdXA-fixed-medium-r-normal--16-160-72-72-m-80-MuleTibetan-1,
4153 ethiopic:-Admas-Ethiomx16f-Medium-R-Normal--16-150-100-100-M-160-Ethiopic-Unicode,
4154 tibetan:-TibMdXA-fixed-medium-r-normal--16-160-72-72-m-160-MuleTibetan-0")
4155 @end smallexample
4156
4157 Many of the international bdf fonts from Intlfonts are type 0, and
4158 therefore need to be added to font-encoding-alist:
4159
4160 @lisp
4161 (setq font-encoding-alist
4162 (append '(("MuleTibetan-0" (tibetan . 0))
4163 ("GB2312" (chinese-gb2312 . 0))
4164 ("JISX0208" (japanese-jisx0208 . 0))
4165 ("JISX0212" (japanese-jisx0212 . 0))
4166 ("VISCII" (vietnamese-viscii-lower . 0))
4167 ("KSC5601" (korean-ksc5601 . 0))
4168 ("MuleArabic-0" (arabic-digit . 0))
4169 ("MuleArabic-1" (arabic-1-column . 0))
4170 ("MuleArabic-2" (arabic-2-column . 0)))
4171 font-encoding-alist))
4172 @end lisp
4173
4174 You can now use the Emacs font menu to select the @samp{bdf: 16-dot medium}
4175 fontset, or you can select it by setting the default font in your
4176 @file{~/.emacs}:
4177
4178 @lisp
4179 (set-default-font "fontset-bdf")
4180 @end lisp
4181
4182
4183 @c ------------------------------------------------------------
4184 @node Mail and news
4185 @chapter Mail and news
4186 @cindex Mail and news
4187
4188 @menu
4189 * Changing the included text prefix::
4190 * Saving a copy of outgoing mail::
4191 * Expanding aliases when sending mail::
4192 * Sorting the messages in an Rmail folder::
4193 * Rmail writes to /var/spool/mail::
4194 * Replying to the sender of a message::
4195 * Automatically starting a mail or news reader::
4196 * Reading news with Emacs::
4197 * Making Gnus faster::
4198 * Catching up in all newsgroups::
4199 @end menu
4200
4201 @node Changing the included text prefix
4202 @section How do I change the included text prefix in mail/news followups?
4203 @cindex Prefix in mail/news followups, changing
4204 @cindex Included text prefix, changing
4205 @cindex Setting the included text character
4206 @cindex Quoting in mail messages
4207
4208 If you read mail with Rmail, set the variable @code{mail-yank-prefix}.
4209 For Gnus, set @code{message-yank-prefix}. For VM, set
4210 @code{vm-included-text-prefix}. For mh-e, set @code{mh-ins-buf-prefix}.
4211
4212 For fancier control of citations, use Supercite (@pxref{Top,, the Supercite
4213 Manual, sc, The Supercite Manual}).
4214
4215 To prevent Emacs from including various headers of the replied-to
4216 message, set the value of @code{mail-yank-ignored-headers} to an
4217 appropriate regexp.
4218
4219 @node Saving a copy of outgoing mail
4220 @section How do I save a copy of outgoing mail?
4221 @cindex Saving a copy of outgoing mail
4222 @cindex Copying outgoing mail to a file
4223 @cindex Filing outgoing mail
4224 @cindex Automatic filing of outgoing mail
4225 @cindex Mail, saving outgoing automatically
4226
4227 You can either mail yourself a copy by including a @samp{BCC} header in the
4228 mail message, or store a copy of the message directly to a file by
4229 including an @samp{FCC} header.
4230
4231 If you use standard mail, you can automatically create a @samp{BCC} to
4232 yourself by putting
4233
4234 @lisp
4235 (setq mail-self-blind t)
4236 @end lisp
4237
4238 @noindent
4239 in your @file{.emacs} file. You can automatically include an @samp{FCC}
4240 field by putting something like the following in your @file{.emacs}
4241 file:
4242
4243 @lisp
4244 (setq mail-archive-file-name (expand-file-name "~/outgoing"))
4245 @end lisp
4246
4247 The output file will be in Unix mail format.
4248
4249 If you use @code{mh-e}, add an @samp{FCC} or @samp{BCC} field to your
4250 components file.
4251
4252 It does not work to put @samp{set record filename} in the @file{.mailrc}
4253 file.
4254
4255 @node Expanding aliases when sending mail
4256 @section Why doesn't Emacs expand my aliases when sending mail?
4257 @cindex Expanding aliases when sending mail
4258 @cindex Mail alias expansion
4259 @cindex Sending mail with aliases
4260
4261 @xref{Mail Aliases,, The Emacs Manual, emacs, The Emacs Manual}.
4262
4263 @itemize @bullet
4264
4265 @item
4266 Normally, Emacs expands aliases when you send the message.
4267 To expand them before this, use @kbd{M-x expand-mail-aliases}.
4268
4269 @item
4270 Emacs normally only reads the @file{.mailrc} file once per session, when
4271 you start to compose your first mail message. If you edit the file
4272 after this, you can use @kbd{M-x build-mail-aliases} to make Emacs
4273 reread it. Prior to Emacs 24.1, this is not an interactive command, so
4274 you must instead type @kbd{M-: (build-mail-aliases) @key{RET}}.
4275
4276 @item
4277 If you like, you can expand mail aliases as abbrevs, as soon as you
4278 type them in. To enable this feature, execute the following:
4279
4280 @lisp
4281 (add-hook 'mail-mode-hook 'mail-abbrevs-setup)
4282 @end lisp
4283
4284 Note that the aliases are expanded automatically only after you type
4285 a word-separator character (e.g., @key{RET} or @kbd{,}). You can force their
4286 expansion by moving point to the end of the alias and typing @kbd{C-x a e}
4287 (@kbd{M-x expand-abbrev}).
4288 @end itemize
4289
4290 @node Sorting the messages in an Rmail folder
4291 @section How can I sort the messages in my Rmail folder?
4292 @cindex Rmail, sorting messages in
4293 @cindex Folder, sorting messages in an Rmail
4294 @cindex Sorting messages in an Rmail folder
4295
4296 In Rmail, type @kbd{C-c C-s C-h} to get a list of sorting functions
4297 and their key bindings.
4298
4299 @node Rmail writes to /var/spool/mail
4300 @section Why does Rmail need to write to @file{/var/spool/mail}?
4301 @cindex Rmail and @file{/var/spool/mail}
4302 @cindex @file{/var/spool/mail} and Rmail
4303
4304 This is the behavior of the @code{movemail} program which Rmail uses.
4305 This indicates that @code{movemail} is configured to use lock files.
4306
4307 RMS writes:
4308
4309 @quotation
4310 Certain systems require lock files to interlock access to mail files.
4311 On these systems, @code{movemail} must write lock files, or you risk losing
4312 mail. You simply must arrange to let @code{movemail} write them.
4313
4314 Other systems use the @code{flock} system call to interlock access. On
4315 these systems, you should configure @code{movemail} to use @code{flock}.
4316 @end quotation
4317
4318 @node Replying to the sender of a message
4319 @section How can I force Rmail to reply to the sender of a message, but not the other recipients?
4320 @cindex Replying only to the sender of a message
4321 @cindex Sender, replying only to
4322 @cindex Rmail, replying to the sender of a message in
4323
4324 @c isaacson@@seas.upenn.edu
4325 Ron Isaacson says: When you hit
4326 @key{r} to reply in Rmail, by default it CCs all of the original
4327 recipients (everyone on the original @samp{To} and @samp{CC}
4328 lists). With a prefix argument (i.e., typing @kbd{C-u} before @key{r}),
4329 it replies only to the sender. However, going through the whole
4330 @kbd{C-u} business every time you want to reply is a pain. This is the
4331 best fix I've been able to come up with:
4332
4333 @lisp
4334 (defun rmail-reply-t ()
4335 "Reply only to the sender of the current message. (See rmail-reply.)"
4336 (interactive)
4337 (rmail-reply t))
4338
4339 (add-hook 'rmail-mode-hook
4340 (lambda ()
4341 (define-key rmail-mode-map "r" 'rmail-reply-t)
4342 (define-key rmail-mode-map "R" 'rmail-reply)))
4343 @end lisp
4344
4345 @node Automatically starting a mail or news reader
4346 @section How do I make Emacs automatically start my mail/news reader?
4347 @cindex Mail reader, starting automatically
4348 @cindex News reader, starting automatically
4349 @cindex Starting mail/news reader automatically
4350
4351 To start Emacs in Gnus:
4352
4353 @example
4354 emacs -f gnus
4355 @end example
4356
4357 @noindent
4358 in Rmail:
4359
4360 @example
4361 emacs -f rmail
4362 @end example
4363
4364 A more convenient way to start with Gnus:
4365
4366 @example
4367 alias gnus 'emacs -f gnus'
4368 gnus
4369 @end example
4370
4371 It is probably unwise to automatically start your mail or news reader
4372 from your @file{.emacs} file. This would cause problems if you needed to run
4373 two copies of Emacs at the same time. Also, this would make it difficult for
4374 you to start Emacs quickly when you needed to.
4375
4376 @node Reading news with Emacs
4377 @section How do I read news under Emacs?
4378 @cindex Reading news under Emacs
4379 @cindex Usenet reader in Emacs
4380 @cindex Gnus newsreader
4381 @cindex FAQ for Gnus
4382 @cindex Gnus FAQ
4383 @cindex Learning more about Gnus
4384
4385 Use @kbd{M-x gnus}. For more information on Gnus, @pxref{Top,, the Gnus
4386 Manual, gnus, The Gnus Manual}, which includes @ref{Frequently Asked
4387 Questions,, the Gnus FAQ, gnus, The Gnus Manual}.
4388
4389
4390 @node Making Gnus faster
4391 @section How do I make Gnus faster?
4392 @cindex Faster, starting Gnus
4393 @cindex Starting Gnus faster
4394 @cindex Gnus, starting faster
4395 @cindex Slow catch up in Gnus
4396 @cindex Gnus is slow when catching up
4397 @cindex Crosspostings make Gnus catching up slow
4398
4399 From the Gnus FAQ (@pxref{Reading news with Emacs}):
4400
4401 @quotation
4402 If you have a slow machine, or are just really impatient, there are a
4403 few things you can do to make Gnus run faster.
4404
4405 Set @code{gnus-check-new-newsgroups} and
4406 @code{gnus-check-bogus-newsgroups} to @code{nil} to make startup faster.
4407
4408 Set @code{gnus-show-threads}, @code{gnus-use-cross-reference} and
4409 @code{gnus-nov-is-evil} to @code{nil} to make entering and exiting the
4410 summary buffer faster.
4411 @end quotation
4412
4413 @node Catching up in all newsgroups
4414 @section How do I catch up all newsgroups in Gnus?
4415 @cindex Catching up all newsgroups in Gnus
4416 @cindex Gnus, Catching up all newsgroups in
4417
4418 In the @file{*Newsgroup*} buffer, type @kbd{M-< C-x ( c y C-x ) M-0 C-x e}
4419
4420 Leave off the initial @kbd{M-<} if you only want to catch up from point
4421 to the end of the @file{*Newsgroup*} buffer.
4422
4423 @node Concept index
4424 @unnumbered Concept Index
4425 @printindex cp
4426
4427 @bye