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1 Copyright (c) 1985 Free Software Foundation, Inc; See end for conditions.
2
3 You are looking at the Emacs tutorial.
4
5 Emacs commands generally involve the CONTROL key (sometimes labeled
6 CTRL or CTL) or the META key (sometimes labeled EDIT or ALT). Rather than
7 write out META or CONTROL each time we want you to prefix a character,
8 we'll use the following abbreviations:
9
10 C-<chr> means hold the CONTROL key while typing the character <chr>
11 Thus, C-f would be: hold the CONTROL key and type f.
12 M-<chr> means hold the META or EDIT or ALT key down while typing <chr>.
13 If there is no META key or equivalent, type <ESC>, release it,
14 then type the character <chr>. "<ESC>" stands for the
15 key labeled "ESC".
16
17 Important note: to end the Emacs session, type C-x C-c. (Two characters.)
18 The characters ">>" at the left margin indicate directions for you to
19 try using a command. For instance:
20 <<Blank lines inserted here by startup of help-with-tutorial>>
21 >> Now type C-v (View next screen) to move to the next screen.
22 (go ahead, do it by depressing the control key and v together).
23 From now on, you'll be expected to do this whenever you finish
24 reading the screen.
25
26 Note that there is an overlap when going from screen to screen; this
27 provides some continuity when moving through the file.
28
29 The first thing that you need to know is how to move around from
30 place to place in the file. You already know how to move forward a
31 screen, with C-v. To move backwards a screen, type M-v (depress the
32 META key and type v, or type <ESC>v if you don't have a META or EDIT
33 key).
34
35 >> Try typing M-v and then C-v to move back and forth a few times.
36
37
38 * SUMMARY
39 ---------
40
41 The following commands are useful for viewing screenfuls:
42
43 C-v Move forward one screenful
44 M-v Move backward one screenful
45 C-l Clear screen and redisplay everything
46 putting the text near the cursor at the center.
47 (That's control-L, not control-1.)
48
49 >> Find the cursor and remember what text is near it.
50 Then type a C-l.
51 Find the cursor again and see what text is near it now.
52
53
54 * BASIC CURSOR CONTROL
55 ----------------------
56
57 Getting from screenful to screenful is useful, but how do you
58 reposition yourself within a given screen to a specific place?
59 There are several ways you can do this. One way (not the best, but
60 the most basic) is to use the commands previous, backward, forward
61 and next. As you can imagine these commands (which are given to
62 Emacs as C-p, C-b, C-f, and C-n respectively) move the cursor from
63 where it currently is to a new place in the given direction. Here,
64 in a more graphical form are the commands:
65
66 Previous line, C-p
67 :
68 :
69 Backward, C-b .... Current cursor position .... Forward, C-f
70 :
71 :
72 Next line, C-n
73
74 >> Move the cursor to the line in the middle of that diagram
75 and type C-l to see the whole diagram centered in the screen.
76
77 You'll probably find it easy to think of these by letter. P for
78 previous, N for next, B for backward and F for forward. These are
79 the basic cursor positioning commands and you'll be using them ALL
80 the time so it would be of great benefit if you learn them now.
81
82 >> Do a few C-n's to bring the cursor down to this line.
83
84 >> Move into the line with C-f's and then up with C-p's.
85 See what C-p does when the cursor is in the middle of the line.
86
87 Lines are separated by Newline characters. For most applications
88 there should normally be a Newline character at the end of the text,
89 as well, but it is up to you to make sure of this. A file can
90 validly exist without a Newline at the end.
91
92 >> Try to C-b at the beginning of a line. Do a few more C-b's.
93 Then do C-f's back to the end of the line and beyond.
94
95 When you go off the top or bottom of the screen, the text beyond
96 the edge is shifted onto the screen so that your instructions can
97 be carried out while keeping the cursor on the screen.
98
99 >> Try to move the cursor off the bottom of the screen with C-n and
100 see what happens.
101
102 If moving by characters is too slow, you can move by words. M-f
103 (Meta-f) moves forward a word and M-b moves back a word.
104
105 >> Type a few M-f's and M-b's. Intersperse them with C-f's and C-b's.
106
107 Notice the parallel between C-f and C-b on the one hand, and M-f and
108 M-b on the other hand. Very often Meta characters are used for
109 operations related to English text whereas Control characters operate
110 on the basic textual units that are independent of what you are
111 editing (characters, lines, etc). There is a similar parallel between
112 lines and sentences: C-a and C-e move to the beginning or end of a
113 line, and M-a and M-e move to the beginning or end of a sentence.
114
115 >> Try a couple of C-a's, and then a couple of C-e's.
116 Try a couple of M-a's, and then a couple of M-e's.
117
118 See how repeated C-a's do nothing, but repeated M-a's keep moving
119 farther. Do you think that this is right?
120
121 Two other simple cursor motion commands are M-< (Meta Less-than),
122 which moves to the beginning of the file, and M-> (Meta Greater-than),
123 which moves to the end of the file. You probably don't need to try
124 them, since finding this spot again will be boring. On most terminals
125 the "<" is above the comma and you must use the shift key to type it.
126 On these terminals you must use the shift key to type M-< also;
127 without the shift key, you would be typing M-comma.
128
129 The location of the cursor in the text is also called "point". To
130 paraphrase, the cursor shows on the screen where point is located in
131 the text.
132
133 Here is a summary of simple moving operations including the word and
134 sentence moving commands:
135
136 C-f Move forward a character
137 C-b Move backward a character
138
139 M-f Move forward a word
140 M-b Move backward a word
141
142 C-n Move to next line
143 C-p Move to previous line
144
145 C-a Move to beginning of line
146 C-e Move to end of line
147
148 M-a Move back to beginning of sentence
149 M-e Move forward to end of sentence
150
151 M-< Go to beginning of file
152 M-> Go to end of file
153
154 >> Try all of these commands now a few times for practice.
155 Since the last two will take you away from this screen,
156 you can come back here with M-v's and C-v's. These are
157 the most often used commands.
158
159 Like all other commands in Emacs, these commands can be given
160 arguments which cause them to be executed repeatedly. The way you
161 give a command a repeat count is by typing C-u and then the digits
162 before you type the command. If you have a META or EDIT key, you can
163 omit the C-u if you hold down the META or EDIT key while you type the
164 digits. This is easier, but we recommend the C-u method because it
165 works on any terminal.
166
167 For instance, C-u 8 C-f moves forward eight characters.
168
169 >> Try giving a suitable argument to C-n or C-p to come as close
170 as you can to this line in one jump.
171
172 The only apparent exception to this is the screen moving commands,
173 C-v and M-v. When given an argument, they scroll the screen up or
174 down by that many lines, rather than screenfuls. This proves to be
175 much more useful.
176
177 >> Try typing C-u 8 C-v now.
178
179 Did it scroll the screen up by 8 lines? If you would like to
180 scroll it down you can give an argument to M-v.
181
182 If you are using X Windows, there is probably a rectangular area
183 called a scroll bar at the right hand side of the Emacs window. You
184 can scroll the text by clicking the mouse in the scroll bar.
185
186 >> Try pressing the middle button at the top of the highlighted area
187 within the scroll bar, then moving the mouse while holding that button
188 down.
189
190 >> Move the mouse to a point in the scroll bar about three lines from
191 the top, and click the left button a couple of times. Then try the
192 right button a couple of times.
193
194
195 * WHEN EMACS IS HUNG
196 --------------------
197
198 If Emacs gets into an infinite (or simply very long) computation which
199 you don't want to finish, you can stop it safely by typing C-g.
200 You can also use C-g to discard a numeric argument or the beginning of
201 a command that you don't want to finish.
202
203 >> Type C-u 100 to make a numeric arg of 100, then type C-g.
204 Now type C-f. How many characters does it move?
205 If you have typed an <ESC> by mistake, you can get rid of it
206 with a C-g.
207
208 If you type <ESC> : then you get a new window appearing on the screen,
209 telling you that M-: is a "disabled command" and asking whether you
210 really want to execute it. The command M-: is marked as disabled
211 because we expect it would confuse beginners and you probably don't
212 want to use it until you know more about Emacs. If you really want to
213 try the M-: command, you could type a Space in answer to the question,
214 and M-: would go ahead. Normally, if you do not want to execute M-:,
215 you would type "n" to answer the question.
216
217 >> Type <ESC> :, then type n.
218
219
220 * WINDOWS
221 ---------
222
223 Emacs can have several windows, each displaying its own text.
224 At this stage it is better not to go into the techniques of
225 using multiple windows. But you do need to know how to get
226 rid of extra windows that may appear to display help or
227 output from certain commands. It is simple:
228
229 C-x 1 One window (i.e., kill all other windows).
230
231 That is Control-x followed by the digit 1.
232 C-x 1 makes the window which the cursor is in become
233 the full screen, by getting rid of any other windows.
234
235 >> Move the cursor to this line and type C-u 0 C-l.
236 >> Type Control-h k Control-f.
237 See how this window shrinks, while a new one appears
238 to display documentation on the Control-f command.
239
240 >> Type C-x 1 and see the documentation listing window disappear.
241
242
243 * INSERTING AND DELETING
244 ------------------------
245
246 If you want to insert text, just type it. Characters which you can
247 see, such as A, 7, *, etc. are taken by Emacs as text and inserted
248 immediately. Type <Return> (the carriage-return key) to insert a
249 Newline character.
250
251 You can delete the last character you typed by typing <Delete>.
252 <Delete> is a key on the keyboard, which may be labeled "Del". In
253 some cases, the "Backspace" key serves as <Delete>, but not always!
254
255 More generally, <Delete> deletes the character immediately before the
256 current cursor position.
257
258 >> Do this now, type a few characters and then delete them
259 by typing <Delete> a few times. Don't worry about this file
260 being changed; you won't affect the master tutorial. This is just
261 a copy of it.
262
263 >> Now start typing text until you reach the right margin, and keep
264 typing. When a line of text gets too big for one line on the
265 screen, the line of text is "continued" onto a second screen line.
266 The backslash at the right margin indicates a line which has
267 been continued.
268 >> Use <Delete>s to delete the text until the line fits on one screen
269 line again. The continuation line goes away.
270
271 >> Move the cursor to the beginning of a line and type <Delete>. This
272 deletes the newline before the line and merges the line onto
273 the previous line. The resulting line may be too long to fit, in
274 which case it has a continuation line.
275 >> Type <Return> to reinsert the Newline you deleted.
276
277 Remember that most Emacs commands can be given a repeat count;
278 this includes characters which insert themselves.
279
280 >> Try that now -- type C-u 8 * and see what happens.
281
282 You've now learned the most basic way of typing something in
283 Emacs and correcting errors. You can delete by words or lines
284 as well. Here is a summary of the delete operations:
285
286 <Delete> delete the character just before the cursor
287 C-d delete the next character after the cursor
288
289 M-<Delete> kill the word immediately before the cursor
290 M-d kill the next word after the cursor
291
292 C-k kill from the cursor position to end of line
293 M-k kill to the end of the current sentence
294
295 Notice that <Delete> and C-d vs M-<Delete> and M-d extend the parallel
296 started by C-f and M-f (well, <Delete> isn't really a control
297 character, but let's not worry about that). C-k and M-k are like C-e
298 and M-e, sort of, in that lines are opposite sentences.
299
300 Now suppose you kill something, and then you decide that you want to
301 get it back? Well, whenever you kill something bigger than a
302 character, Emacs saves it for you. To yank it back, use C-y. You
303 can kill text in one place, move elsewhere, and then do C-y; this is
304 a good way to move text around. Note that the difference
305 between "Killing" and "Deleting" something is that "Killed" things
306 can be yanked back, and "Deleted" things cannot. Generally, the
307 commands that can destroy a lot of text save it, while the ones that
308 attack only one character, or nothing but blank lines and spaces, do
309 not save.
310
311 For instance, type C-n a couple times to position the cursor
312 at some line on this screen.
313
314 >> Do this now, move the cursor and kill that line with C-k.
315
316 Note that a single C-k kills the contents of the line, and a second
317 C-k kills the line itself, and make all the other lines move up. If
318 you give C-k a repeat count, it kills that many lines AND their
319 contents.
320
321 The text that has just disappeared is saved so that you can
322 retrieve it. To retrieve the last killed text and put it where
323 the cursor currently is, type C-y.
324
325 >> Try it; type C-y to yank the text back.
326
327 Think of C-y as if you were yanking something back that someone
328 took away from you. Notice that if you do several C-k's in a row
329 the text that is killed is all saved together so that one C-y will
330 yank all of the lines.
331
332 >> Do this now, type C-k several times.
333
334 Now to retrieve that killed text:
335
336 >> Type C-y. Then move the cursor down a few lines and type C-y
337 again. You now see how to copy some text.
338
339 What do you do if you have some text you want to yank back, and then
340 you kill something else? C-y would yank the more recent kill. But
341 the previous text is not lost. You can get back to it using the M-y
342 command. After you have done C-y to get the most recent kill, typing
343 M-Y replaces that yanked text with the previous kill. Typing M-y
344 again and again brings in earlier and earlier kills. When you
345 have reached the text you are looking for, you can just go away and
346 leave it there. If you M-y enough times, you come back to the
347 starting point (the most recent kill).
348
349 >> Kill a line, move around, kill another line.
350 Then do C-y to get back the second killed line.
351 Then do M-y and it will be replaced by the first killed line.
352 Do more M-y's and see what you get. Keep doing them until
353 the second kill line comes back, and then a few more.
354 If you like, you can try giving M-y positive and negative
355 arguments.
356
357
358 * UNDO
359 ------
360
361 Any time you make a change to the text and wish you had not done so,
362 you can undo the change (return the text to its previous state)
363 with the undo command, C-x u. Normally, C-x u undoes one command's
364 worth of changes; if you repeat the C-x u several times in a row,
365 each time undoes one more command. There are two exceptions:
366 commands that made no change (just moved the cursor) do not count,
367 and self-inserting characters are often lumped together in groups
368 of up to 20. This is to reduce the number of C-x u's you have to type.
369
370 >> Kill this line with C-k, then type C-x u and it should reappear.
371
372 C-_ is another command for undoing; it is just the same as C-x u
373 but easier to type several times in a row. The problem with C-_ is
374 that on some keyboards it is not obvious how to type it. That is
375 why C-x u is provided as well. On some DEC terminals, you can type
376 C-_ by typing / while holding down CTRL. Illogical, but what can
377 you expect from DEC?
378
379 Giving a numeric argument to C-_ or C-x u is equivalent to repeating
380 it as many times as the argument says.
381
382
383 * FILES
384 -------
385
386 In order to make the text you edit permanent, you must put it in a
387 file. Otherwise, it will go away when your invocation of Emacs goes
388 away. You put your editing in a file by "finding" the file. What
389 finding means is that you see the contents of the file in your Emacs;
390 and, loosely speaking, what you are editing is the file itself.
391 However, the changes still don't become permanent until you "save" the
392 file. This is so you can have control to avoid leaving a half-changed
393 file around when you don't want to. Even then, Emacs leaves the
394 original file under a changed name in case your changes turn out
395 to be a mistake.
396
397 If you look near the bottom of the screen you will see a line that
398 begins and ends with dashes, and contains the string "Emacs: TUTORIAL".
399 Your copy of the Emacs tutorial is called "TUTORIAL". Whatever
400 file you find, that file's name will appear in that precise
401 spot.
402
403 The commands for finding and saving files are unlike the other
404 commands you have learned in that they consist of two characters.
405 They both start with the character Control-x. There is a whole series
406 of commands that start with Control-x; many of them have to do with
407 files, buffers, and related things, and all of them consist of
408 Control-x followed by some other character.
409
410 Another thing about the command for finding a file is that you have
411 to say what file name you want. We say the command "reads an argument
412 from the terminal" (in this case, the argument is the name of the
413 file). After you type the command
414
415 C-x C-f Find a file
416
417 Emacs asks you to type the file name. It echoes on the bottom
418 line of the screen. You are using the minibuffer now! this is
419 what the minibuffer is for. When you type <Return> to end the
420 file name, the minibuffer is no longer needed, so it disappears.
421
422 >> Type C-x C-f, then type C-g. This cancels the minibuffer,
423 and also cancels the C-x C-f command that was using the
424 minibuffer. So you do not find any file.
425
426 In a little while the file contents appear on the screen. You can
427 edit the contents. When you wish to make the changes permanent,
428 issue the command
429
430 C-x C-s Save the file
431
432 The contents of Emacs are written into the file. The first time you
433 do this, the original file is renamed to a new name so that it
434 is not lost. The new name is made by appending "~" to the end
435 of the original file's name.
436
437 When saving is finished, Emacs prints the name of the file written.
438 You should save fairly often, so that you will not lose very much
439 work if the system should crash.
440
441 >> Type C-x C-s, saving your copy of the tutorial.
442 This should print "Wrote .../TUTORIAL" at the bottom of the screen.
443 On VMS it will print "Wrote ...[...]TUTORIAL."
444
445 NOTE: On some systems, typing C-x C-s will freeze the screen and you
446 will see no further output from Emacs. This indicates that an
447 operating system "feature" called "flow control" is intercepting the
448 C-s and not letting it get through to Emacs. To unfreeze the screen,
449 type C-q. Then see the section "Spontaneous Entry to Incremental
450 Search" in the Emacs manual for advice on dealing with this "feature".
451
452 To make a new file, just find it "as if" it already existed. Then
453 start typing in the text. When you ask to "save" the file, Emacs
454 will really create the file with the text that you have inserted.
455 From then on, you can consider yourself to be editing an already
456 existing file.
457
458
459 * BUFFERS
460 ---------
461
462 If you find a second file with C-x C-f, the first file remains
463 inside Emacs. You can switch back to it by finding it again with
464 C-x C-f. This way you can get quite a number of files inside Emacs.
465
466 The object inside Emacs which holds the text read from one file
467 is called a "buffer." Finding a file makes a new buffer inside Emacs.
468 To see a list of the buffers that exist in Emacs, type
469
470 C-x C-b List buffers
471
472 >> Try C-x C-b now.
473
474 See how each buffer has a name, and it may also have a file name
475 for the file whose contents it holds. Some buffers do not correspond
476 to files. For example, the buffer named "*Buffer List*" does
477 not have any file. It is the buffer which contains the buffer
478 list that was made by C-x C-b. ANY text you see in an Emacs window
479 has to be in some buffer.
480
481 >> Type C-x 1 to get rid of the buffer list.
482
483 If you make changes to the text of one file, then find another file,
484 this does not save the first file. Its changes remain inside Emacs,
485 in that file's buffer. The creation or editing of the second file's
486 buffer has no effect on the first file's buffer. This is very useful,
487 but it also means that you need a convenient way to save the first
488 file's buffer. It would be a nuisance to have to switch back to
489 it with C-x C-f in order to save it with C-x C-s. So we have
490
491 C-x s Save some buffers
492
493 C-x s goes through the list of all the buffers you have
494 and finds the ones that contain files you have changed.
495 For each such buffer, C-x s asks you whether to save it.
496
497
498 * EXTENDING THE COMMAND SET
499 ---------------------------
500
501 There are many, many more Emacs commands than could possibly be put
502 on all the control and meta characters. Emacs gets around this with
503 the X (eXtend) command. This comes in two flavors:
504
505 C-x Character eXtend. Followed by one character.
506 M-x Named command eXtend. Followed by a long name.
507
508 These are commands that are generally useful but used less than the
509 commands you have already learned about. You have already seen two
510 of them: the file commands C-x C-f to Find and C-x C-s to Save.
511 Another example is the command to tell Emacs that you'd like to stop
512 editing and get rid of Emacs. The command to do this is C-x C-c.
513 (Don't worry; it offers to save each changed file before it kills the
514 Emacs.)
515
516 C-z is the command to exit Emacs *temporarily*--so that you can go
517 back to the same Emacs session afterward.
518
519 On systems which allow it, C-z exits from Emacs to the shell but does
520 not destroy the Emacs; if you use the C shell, you can resume Emacs
521 with the `fg' command (or, more generally, with `%emacs', which works
522 even if your most recent job was some other). On systems which don't
523 implement suspending, C-z creates a subshell running under Emacs to
524 give you the chance to run other programs and return to Emacs
525 afterward; it does not truly "exit" from Emacs. In this case, the
526 shell command `exit' is the usual way to get back to Emacs from the
527 subshell.
528
529 The time to use C-x C-c is when you are about to log out. It's also
530 the right thing to use to exit an Emacs invoked under mail handling
531 programs and other random utilities, since they may not know how to
532 cope with suspension of Emacs. On other occasions, use C-z, and
533 resume the Emacs when you have more editing to do.
534
535 There are many C-x commands. The ones you know are:
536
537 C-x C-f Find file.
538 C-x C-s Save file.
539 C-x C-b List buffers.
540 C-x C-c Quit Emacs.
541 C-x u Undo.
542
543 Named eXtended commands are commands which are used even less
544 frequently, or commands which are used only in certain modes. These
545 commands are usually called "functions". An example is the function
546 replace-string, which globally replaces one string with another. When
547 you type M-x, Emacs prompts you at the bottom of the screen with
548 M-x and you should type the name of the function you wish to call; in
549 this case, "replace-string". Just type "repl s<TAB>" and Emacs will
550 complete the name. End the command name with <Return>.
551 Then type the two "arguments"--the string to be replaced, and the string
552 to replace it with--each one ended with a Return.
553
554 >> Move the cursor to the blank line two lines below this one.
555 Then type M-x repl s<Return>changed<Return>altered<Return>.
556
557 Notice how this line has changed: you've replaced
558 the word c-h-a-n-g-e-d with "altered" wherever it occurred
559 after the cursor.
560
561
562 * AUTO SAVE
563 -----------
564
565 When you have made changes in a file, but you have not saved them yet,
566 they could be lost if your computer crashes. To protect you from
567 this, Emacs writes "auto save" files periodically. The auto save file
568 name has a # at the beginning and the end; for example, if your file
569 is named "hello.c", its auto save file's name is "#hello.c#". When
570 you save the file in the normal way, its auto save file is no longer
571 necessary so Emacs deletes it.
572
573 If the computer crashes, you can recover your auto-saved editing by
574 finding the file normally (the file you were editing, not the auto
575 save file) and then typing M-x recover file<return>. When it asks for
576 confirmation, type yes<return> to go ahead and recover the auto-save
577 data.
578
579
580 * MODE LINE
581 -----------
582
583 If Emacs sees that you are typing commands slowly it shows them to you
584 at the bottom of the screen in an area called the "echo area." The echo
585 area contains the bottom line of the screen. The line immediately above
586 it is called the MODE LINE. The mode line says something like
587
588 --**-Emacs: TUTORIAL (Fundamental)--58%----------------------
589
590 This is a very useful "information" line.
591
592 You already know what the filename means--it is the file you have
593 found. What the --NN%-- means is that NN percent of the file is
594 above the top of the screen. If the top of the file is on the screen,
595 it will say --Top-- instead of --00%--. If the bottom of the file is
596 on the screen, it will say --Bot--. If you are looking at a file so
597 small it all fits on the screen, it says --All--.
598
599 The stars near the front mean that you have made changes to the text.
600 Right after you visit or save a file, there are no stars, just dashes.
601
602 The part of the mode line inside the parentheses is to tell you what
603 modes you are in. The default mode is Fundamental which is what you
604 are in now. It is an example of a "major mode". There are several
605 major modes in Emacs for editing different languages and text, such as
606 Lisp mode, Text mode, etc. At any time one and only one major mode is
607 active, and its name can always be found in the mode line just where
608 "Fundamental" is now. Each major mode makes a few commands behave
609 differently. For example, there are commands for creating comments in
610 a program, and since each programming language has a different idea of
611 what a comment should look like, each major mode has to insert
612 comments differently. Each major mode is the name of an extended
613 command, which is how you get into the mode. For example,
614 M-x fundamental-mode is how to get into Fundamental mode.
615
616 If you are going to be editing English text, such as this file, you
617 should probably use Text Mode.
618 >> Type M-x text-mode<Return>.
619
620 Don't worry, none of the commands you have learned changes Emacs in
621 any great way. But you can observe that apostrophes are now part of
622 words when you do M-f or M-b. Major modes are usually like that:
623 commands don't change into completely unrelated things, but they work
624 a little bit differently.
625
626 To get documentation on your current major mode, type C-h m.
627
628 >> Use C-u C-v once or more to bring this line near the top of screen.
629 >> Type C-h m, to see how Text mode differs from Fundamental mode.
630 >> Type C-x 1 to remove the documentation from the screen.
631
632 Major modes are called major because there are also minor modes.
633 They are called minor because they aren't alternatives to the major
634 modes, just minor modifications of them. Each minor mode can be
635 turned on or off by itself, regardless of what major mode you are in,
636 and regardless of the other minor modes. So you can use no minor
637 modes, or one minor mode, or any combination of several minor modes.
638
639 One minor mode which is very useful, especially for editing English
640 text, is Auto Fill mode. When this mode is on, Emacs breaks the line
641 in between words automatically whenever the line gets too long. You
642 can turn this mode on by doing M-x auto-fill-mode<Return>. When the
643 mode is on, you can turn it off by doing M-x auto-fill-mode<Return>.
644 If the mode is off, this function turns it on, and if the mode is on,
645 this function turns it off. This is called "toggling".
646
647 >> Type M-x auto-fill-mode<Return> now. Then insert a line of "asdf "
648 over again until you see it divide into two lines. You must put in
649 spaces between them because Auto Fill breaks lines only at spaces.
650
651 The margin is usually set at 70 characters, but you can change it
652 with the C-x f command. You should give the margin setting you want
653 as a numeric argument.
654
655 >> Type C-x f with an argument of 20. (C-u 2 0 C-x f).
656 Then type in some text and see Emacs fill lines of 20
657 characters with it. Then set the margin back to 70 using
658 C-x f again.
659
660 If you makes changes in the middle of a paragraph, Auto Fill mode
661 does not re-fill it for you.
662 To re-fill the paragraph, type M-q (Meta-q) with the cursor inside
663 that paragraph.
664
665 >> Move the cursor into the previous paragraph and type M-q.
666
667 * SEARCHING
668 -----------
669
670 Emacs can do searches for strings (these are groups of contiguous
671 characters or words) either forward through the file or backward
672 through it. To search for the string means that you are trying to
673 locate it somewhere in the file and have Emacs show you where the
674 occurrences of the string exist. This type of search is somewhat
675 different from what you may be familiar with. It is a search that is
676 performed as you type in the thing to search for. The command to
677 initiate a search is C-s for forward search, and C-r for reverse
678 search. BUT WAIT! Don't do them now. When you type C-s you'll
679 notice that the string "I-search" appears as a prompt in the echo
680 area. This tells you that Emacs is in what is called an incremental
681 search waiting for you to type the thing that you want to search for.
682 <RET> terminates a search.
683
684 >> Now type C-s to start a search. SLOWLY, one letter at a time,
685 type the word 'cursor', pausing after you type each
686 character to notice what happens to the cursor.
687 >> Type C-s to find the next occurrence of "cursor".
688 >> Now type <Delete> four times and see how the cursor moves.
689 >> Type <RET> to terminate the search.
690
691 Did you see what happened? Emacs, in an incremental search, tries to
692 go to the occurrence of the string that you've typed out so far. To go
693 to the next occurrence of 'cursor' just type C-s again. If no such
694 occurrence exists Emacs beeps and tells you that it is a failing
695 search. C-g would also terminate the search.
696
697 NOTE: On some systems, typing C-s will freeze the screen and you will
698 see no further output from Emacs. This indicates that an operating
699 system "feature" called "flow control" is intercepting the C-s and not
700 letting it get through to Emacs. To unfreeze the screen, type C-q.
701 Then see the section "Spontaneous Entry to Incremental Search" in the
702 Emacs manual for advice on dealing with this "feature".
703
704 If you are in the middle of an incremental search and type <Delete>,
705 you'll notice that the last character in the search string is erased
706 and the search backs up to the last place of the search. For
707 instance, suppose you currently have typed 'cu' and you see that your
708 cursor is at the first occurrence of 'cu'. If you now type <Delete>,
709 the 'u' on the search line is erased and you'll be repositioned in the
710 text to the occurrence of 'c' where the search took you before you
711 typed the 'u'. This provides a useful means for backing up while you
712 are searching.
713
714 If you are in the middle of a search and type a control or meta
715 character (with a few exceptions--characters that are special in
716 a search, such as C-s and C-r), the search is terminated.
717
718 The C-s starts a search that looks for any occurrence of the search
719 string AFTER the current cursor position. But what if you want to
720 search for something earlier in the text? To do this, type C-r for
721 Reverse search. Everything that applies to C-s applies to C-r except
722 that the direction of the search is reversed.
723
724
725 * MULTIPLE WINDOWS
726 ------------------
727
728 One of the nice features of Emacs is that you can display more than one
729 window on the screen at the same time.
730
731 >> Move the cursor to this line and type C-u 0 C-l.
732
733 >> Now type C-x 2 which splits the screen into two windows.
734 Both windows display this tutorial. The cursor stays in the top window.
735
736 >> Type C-M-v to scroll the bottom window.
737 (If you don't have a real Meta key, type ESC C-v.)
738
739 >> Type C-x o ("o" for "other") to move the cursor to the bottom window.
740 >> Use C-v and M-v in the bottom window to scroll it.
741 Keep reading these directions in the top window.
742
743 >> Type C-x o again to move the cursor back to the top window.
744 The cursor is still just where it was in the top window before.
745
746 You can keep using C-x o to switch between the windows. Each
747 window has its own cursor position, but only one window actually
748 shows the cursor. All the ordinary editing commands apply to the
749 window that the cursor is in.
750
751 The command C-M-v is very useful when you are editing text in one
752 window and using the other window just for reference. You can keep
753 the cursor always in the window where you are editing, and edit
754 there as you advance through the other window.
755
756 C-M-v is an example of a CONTROL-META character. If you have a real
757 META key, you can type C-M-v by holding down both CTRL and META while
758 typing v.
759
760 It doesn't matter whether CTRL or META "comes first," because both of
761 these keys act by modifying the characters you type. But if you don't
762 have a real META key, and you use ESC instead, the order does matter:
763 you must type ESC followed by CTRL-v; CTRL-ESC v will not work. This
764 is because ESC is a character in its own right, not a modifier key.
765
766 >> Type C-x 1 (in the top window) to get rid of the bottom window.
767
768 (If you had typed C-x 1 in the bottom window, that would get rid
769 of the top one. Think of this command as "Keep just one
770 window--the window I am already in.")
771
772 You don't have to display the same buffer in both windows. If
773 you use C-x C-f to find a file in one window, the other window
774 doesn't change. You can pick a file in each window
775 independently.
776
777 Here is another way to use two windows to display two different
778 things:
779
780 >> Type C-x 4 C-f followed by the name of one of your files.
781 End with <RETURN>. See the specified file appear in the bottom
782 window. The cursor goes there, too.
783
784 >> Type C-x o to go back to the top window, and C-x 1 to delete
785 the bottom window.
786
787
788 * RECURSIVE EDITING LEVELS
789 --------------------------
790
791 Sometimes you will get into what is called a "recursive editing
792 level". This is indicated by square brackets in the mode line,
793 surrounding the parentheses around the major mode name. For
794 example, you might see [(Fundamental)] instead of (Fundamental).
795
796 To get out of the recursive editing level, type
797 M-x top-level<Return>.
798
799 >> Try that now; it should display "Back to top level"
800 at the bottom of the screen.
801
802 In fact, you were ALREADY at top level (not inside a recursive editing
803 level) if you have obeyed instructions. M-x top-level does not care;
804 it gets out of any number of recursive editing levels, perhaps zero,
805 to get back to top level.
806
807 You can't use C-g to get out of a recursive editing level because C-g
808 is used for discarding numeric arguments and partially typed commands
809 WITHIN the recursive editing level.
810
811
812 * GETTING MORE HELP
813 -------------------
814
815 In this tutorial we have tried to supply just enough information to
816 get you started using Emacs. There is so much available in Emacs that
817 it would be impossible to explain it all here. However, you may want
818 to learn more about Emacs since it has numerous desirable features
819 that you don't know about yet. Emacs has a great deal of internal
820 documentation. All of these commands can be accessed through
821 the character Control-h, which we call "the Help character"
822 because of the function it serves.
823
824 To use the HELP features, type the C-h character, and then a
825 character saying what kind of help you want. If you are REALLY lost,
826 type C-h ? and Emacs will tell you what kinds of help it can give.
827 If you have typed C-h and decide you don't want any help, just
828 type C-g to cancel it.
829
830 (Some sites rebind the character C-h. They really shouldn't do this
831 as a blanket measure, so complain to the operator. Meanwhile, if C-h
832 does not display a message about help at the bottom of the screen, try
833 typing M-x help RET instead.)
834
835 The most basic HELP feature is C-h c. Type C-h, a c, and a
836 command character or sequence, and Emacs displays a very brief
837 description of the command.
838
839 >> Type C-h c Control-p.
840 The message should be something like
841
842 C-p runs the command previous-line
843
844 This tells you the "name of the function". That is important in
845 writing Lisp code to extend Emacs; it also is enough to remind
846 you of what the command does if you have seen it before but did
847 not remember.
848
849 Multi-character commands such as C-x C-s and (if you have no META or
850 EDIT key) <ESC>v are also allowed after C-h c.
851
852 To get more information on the command, use C-h k instead of C-h c.
853
854 >> Type C-h k Control-p.
855
856 This displays the documentation of the function, as well as its
857 name, in an Emacs window. When you are finished reading the
858 output, type C-x 1 to get rid of the help text. You do not have
859 to do this right away. You can do some editing while referring
860 to the help text and then type C-x 1.
861
862 Here are some other useful C-h options:
863
864 C-h f Describe a function. You type in the name of the
865 function.
866
867 >> Try typing C-h f previous-line<Return>.
868 This prints all the information Emacs has about the
869 function which implements the C-p command.
870
871 C-h a Command Apropos. Type in a keyword and Emacs will list
872 all the commands whose names contain that keyword.
873 These commands can all be invoked with Meta-x.
874 For some commands, Command Apropos will also list a one
875 or two character sequence which has the same effect.
876
877 >> Type C-h a file<Return>.
878
879 This displays in another window a list of all M-x commands with
880 "file" in their names. You will also see commands like C-x C-f
881 and C-x C-w, listed beside the command names find-file and
882 write-file.
883
884 >> Type C-M-v to scroll the help window. Do this a few times.
885
886 >> Type C-x 1 to delete the help window.
887
888
889 * CONCLUSION
890 ------------
891
892 Remember, to exit Emacs permanently use C-x C-c. To exit to a shell
893 temporarily, so that you can come back in, use C-z.
894
895 This tutorial is meant to be understandable to all new users, so if
896 you found something unclear, don't sit and blame yourself - complain!
897
898
899 COPYING
900 -------
901
902 This tutorial descends from a long line of Emacs tutorials
903 starting with the one written by Stuart Cracraft for the original Emacs.
904
905 This version of the tutorial, like GNU Emacs, is copyrighted, and
906 comes with permission to distribute copies on certain conditions:
907
908 Copyright (c) 1985 Free Software Foundation
909
910 Permission is granted to anyone to make or distribute verbatim copies
911 of this document as received, in any medium, provided that the
912 copyright notice and permission notice are preserved,
913 and that the distributor grants the recipient permission
914 for further redistribution as permitted by this notice.
915
916 Permission is granted to distribute modified versions
917 of this document, or of portions of it,
918 under the above conditions, provided also that they
919 carry prominent notices stating who last altered them.
920
921 The conditions for copying Emacs itself are slightly different
922 but in the same spirit. Please read the file COPYING and then
923 do give copies of GNU Emacs to your friends.
924 Help stamp out software obstructionism ("ownership") by using,
925 writing, and sharing free software!