Merge from emacs--rel--22
[bpt/emacs.git] / etc / tutorials / TUTORIAL
1 Emacs tutorial. See end for copying conditions.
2
3 Emacs commands generally involve the CONTROL key (sometimes labeled
4 CTRL or CTL) or the META key (sometimes labeled EDIT or ALT). Rather than
5 write that in full each time, we'll use the following abbreviations:
6
7 C-<chr> means hold the CONTROL key while typing the character <chr>
8 Thus, C-f would be: hold the CONTROL key and type f.
9 M-<chr> means hold the META or EDIT or ALT key down while typing <chr>.
10 If there is no META, EDIT or ALT key, instead press and release the
11 ESC key and then type <chr>. We write <ESC> for the ESC key.
12
13 Important note: to end the Emacs session, type C-x C-c. (Two characters.)
14 The characters ">>" at the left margin indicate directions for you to
15 try using a command. For instance:
16 <<Blank lines inserted around following line by help-with-tutorial>>
17 [Middle of page left blank for didactic purposes. Text continues below]
18 >> Now type C-v (View next screen) to move to the next screen.
19 (go ahead, do it by holding down the CONTROL key while typing v).
20 From now on, you should do this again whenever you finish
21 reading the screen.
22
23 Note that there is an overlap of two lines when you move from screen
24 to screen; this provides some continuity so you can continue reading
25 the text.
26
27 The first thing that you need to know is how to move around from place
28 to place in the text. You already know how to move forward one screen,
29 with C-v. To move backwards one screen, type M-v (hold down the META key
30 and type v, or type <ESC>v if you do not have a META, EDIT, or ALT key).
31
32 >> Try typing M-v and then C-v, a few times.
33
34
35 * SUMMARY
36 ---------
37
38 The following commands are useful for viewing screenfuls:
39
40 C-v Move forward one screenful
41 M-v Move backward one screenful
42 C-l Clear screen and redisplay all the text,
43 moving the text around the cursor
44 to the center of the screen.
45 (That's CONTROL-L, not CONTROL-1.)
46
47 >> Find the cursor, and note what text is near it.
48 Then type C-l.
49 Find the cursor again and notice that the same text
50 is near the cursor now.
51
52 You can also use the PageUp and PageDn keys to move by screenfuls, if
53 your terminal has them, but you can edit more efficiently if you use
54 C-v and M-v.
55
56
57 * BASIC CURSOR CONTROL
58 ----------------------
59
60 Moving from screenful to screenful is useful, but how do you
61 move to a specific place within the text on the screen?
62
63 There are several ways you can do this. You can use the arrow keys,
64 but it's more efficient to keep your hands in the standard position
65 and use the commands C-p, C-b, C-f, and C-n. These characters
66 are equivalent to the four arrow keys, like this:
67
68 Previous line, C-p
69 :
70 :
71 Backward, C-b .... Current cursor position .... Forward, C-f
72 :
73 :
74 Next line, C-n
75
76 >> Move the cursor to the line in the middle of that diagram
77 using C-n or C-p. Then type C-l to see the whole diagram
78 centered in the screen.
79
80 You'll find it easy to remember these letters by words they stand for:
81 P for previous, N for next, B for backward and F for forward. You
82 will be using these basic cursor positioning commands all the time.
83
84 >> Do a few C-n's to bring the cursor down to this line.
85
86 >> Move into the line with C-f's and then up with C-p's.
87 See what C-p does when the cursor is in the middle of the line.
88
89 Each line of text ends with a Newline character, which serves to
90 separate it from the following line. The last line in your file ought
91 to have a Newline at the end (but Emacs does not require it to have
92 one).
93
94 >> Try to C-b at the beginning of a line. It should move to
95 the end of the previous line. This is because it moves back
96 across the Newline character.
97
98 C-f can move across a Newline just like C-b.
99
100 >> Do a few more C-b's, so you get a feel for where the cursor is.
101 Then do C-f's to return to the end of the line.
102 Then do one more C-f to move to the following line.
103
104 When you move past the top or bottom of the screen, the text beyond
105 the edge shifts onto the screen. This is called "scrolling". It
106 enables Emacs to move the cursor to the specified place in the text
107 without moving it off the screen.
108
109 >> Try to move the cursor off the bottom of the screen with C-n, and
110 see what happens.
111
112 If moving by characters is too slow, you can move by words. M-f
113 (META-f) moves forward a word and M-b moves back a word.
114
115 >> Type a few M-f's and M-b's.
116
117 When you are in the middle of a word, M-f moves to the end of the word.
118 When you are in whitespace between words, M-f moves to the end of the
119 following word. M-b works likewise in the opposite direction.
120
121 >> Type M-f and M-b a few times, interspersed with C-f's and C-b's
122 so that you can observe the action of M-f and M-b from various
123 places inside and between words.
124
125 Notice the parallel between C-f and C-b on the one hand, and M-f and
126 M-b on the other hand. Very often Meta characters are used for
127 operations related to the units defined by language (words, sentences,
128 paragraphs), while Control characters operate on basic units that are
129 independent of what you are editing (characters, lines, etc).
130
131 This parallel applies between lines and sentences: C-a and C-e move to
132 the beginning or end of a line, and M-a and M-e move to the beginning
133 or end of a sentence.
134
135 >> Try a couple of C-a's, and then a couple of C-e's.
136 Try a couple of M-a's, and then a couple of M-e's.
137
138 See how repeated C-a's do nothing, but repeated M-a's keep moving one
139 more sentence. Although these are not quite analogous, each one seems
140 natural.
141
142 The location of the cursor in the text is also called "point". To
143 paraphrase, the cursor shows on the screen where point is located in
144 the text.
145
146 Here is a summary of simple cursor-moving operations, including the
147 word and sentence moving commands:
148
149 C-f Move forward a character
150 C-b Move backward a character
151
152 M-f Move forward a word
153 M-b Move backward a word
154
155 C-n Move to next line
156 C-p Move to previous line
157
158 C-a Move to beginning of line
159 C-e Move to end of line
160
161 M-a Move back to beginning of sentence
162 M-e Move forward to end of sentence
163
164 >> Try all of these commands now a few times for practice.
165 These are the most often used commands.
166
167 Two other important cursor motion commands are M-< (META Less-than),
168 which moves to the beginning of the whole text, and M-> (META
169 Greater-than), which moves to the end of the whole text.
170
171 On most terminals, the "<" is above the comma, so you must use the
172 shift key to type it. On these terminals you must use the shift key
173 to type M-< also; without the shift key, you would be typing M-comma.
174
175 >> Try M-< now, to move to the beginning of the tutorial.
176 Then use C-v repeatedly to move back here.
177
178 >> Try M-> now, to move to the end of the tutorial.
179 Then use M-v repeatedly to move back here.
180
181 You can also move the cursor with the arrow keys, if your terminal has
182 arrow keys. We recommend learning C-b, C-f, C-n and C-p for three
183 reasons. First, they work on all kinds of terminals. Second, once
184 you gain practice at using Emacs, you will find that typing these Control
185 characters is faster than typing the arrow keys (because you do not
186 have to move your hands away from touch-typing position). Third, once
187 you form the habit of using these Control character commands, you can
188 easily learn to use other advanced cursor motion commands as well.
189
190 Most Emacs commands accept a numeric argument; for most commands, this
191 serves as a repeat-count. The way you give a command a repeat count
192 is by typing C-u and then the digits before you type the command. If
193 you have a META (or EDIT or ALT) key, there is another, alternative way
194 to enter a numeric argument: type the digits while holding down the
195 META key. We recommend learning the C-u method because it works on
196 any terminal. The numeric argument is also called a "prefix argument",
197 because you type the argument before the command it applies to.
198
199 For instance, C-u 8 C-f moves forward eight characters.
200
201 >> Try using C-n or C-p with a numeric argument, to move the cursor
202 to a line near this one with just one command.
203
204 Most commands use the numeric argument as a repeat count, but some
205 commands use it in some other way. Several commands (but none of
206 those you have learned so far) use it as a flag--the presence of a
207 prefix argument, regardless of its value, makes the command do
208 something different.
209
210 C-v and M-v are another kind of exception. When given an argument,
211 they scroll the screen up or down by that many lines, rather than by a
212 screenful. For example, C-u 8 C-v scrolls the screen by 8 lines.
213
214 >> Try typing C-u 8 C-v now.
215
216 This should have scrolled the screen up by 8 lines. If you would like
217 to scroll it down again, you can give an argument to M-v.
218
219 If you are using a windowed display, such as X11 or MS-Windows, there
220 should be a tall rectangular area called a scroll bar at the
221 side of the Emacs window. You can scroll the text by clicking the
222 mouse in the scroll bar.
223
224 >> Try pressing the middle button at the top of the highlighted area
225 within the scroll bar. This should scroll the text to a position
226 determined by how high or low you click.
227
228 >> Try moving the mouse up and down, while holding the middle button
229 pressed down. You'll see that the text scrolls up and down as
230 you move the mouse.
231
232
233 * WHEN EMACS IS HUNG
234 --------------------
235
236 If Emacs stops responding to your commands, you can stop it safely by
237 typing C-g. You can use C-g to stop a command which is taking too
238 long to execute.
239
240 You can also use C-g to discard a numeric argument or the beginning of
241 a command that you do not want to finish.
242
243 >> Type C-u 100 to make a numeric arg of 100, then type C-g.
244 Now type C-f. It should move just one character,
245 because you canceled the argument with C-g.
246
247 If you have typed an <ESC> by mistake, you can get rid of it
248 with a C-g.
249
250
251 * DISABLED COMMANDS
252 -------------------
253
254 Some Emacs commands are "disabled" so that beginning users cannot use
255 them by accident.
256
257 If you type one of the disabled commands, Emacs displays a message
258 saying what the command was, and asking you whether you want to go
259 ahead and execute the command.
260
261 If you really want to try the command, type <SPC> (the Space bar) in
262 answer to the question. Normally, if you do not want to execute the
263 disabled command, answer the question with "n".
264
265 >> Type C-x C-l (which is a disabled command),
266 then type n to answer the question.
267
268
269 * WINDOWS
270 ---------
271
272 Emacs can have several windows, each displaying its own text. We will
273 explain later on how to use multiple windows. Right now we want to
274 explain how to get rid of extra windows and go back to basic
275 one-window editing. It is simple:
276
277 C-x 1 One window (i.e., kill all other windows).
278
279 That is CONTROL-x followed by the digit 1. C-x 1 expands the window
280 which contains the cursor, to occupy the full screen. It deletes all
281 other windows.
282
283 >> Move the cursor to this line and type C-u 0 C-l.
284 >> Type CONTROL-h k CONTROL-f.
285 See how this window shrinks, while a new one appears
286 to display documentation on the CONTROL-f command.
287
288 >> Type C-x 1 and see the documentation listing window disappear.
289
290 This command is unlike the other commands you have learned in that it
291 consists of two characters. It starts with the character CONTROL-x.
292 There is a whole series of commands that start with CONTROL-x; many of
293 them have to do with windows, files, buffers, and related things.
294 These commands are two, three or four characters long.
295
296
297 * INSERTING AND DELETING
298 ------------------------
299
300 If you want to insert text, just type the text. Characters which you
301 can see, such as A, 7, *, etc. are taken by Emacs as text and inserted
302 immediately. Type <Return> (the carriage-return key) to insert a
303 Newline character.
304
305 You can delete the last character you typed by typing <Delback>.
306 <Delback> is a key on the keyboard--the same one you normally use,
307 outside Emacs, for deleting the last character you typed. It is
308 normally a large key a couple of lines up from the <Return> key, and
309 it is usually labeled "Delete", "Del" or "Backspace".
310
311 If the large key there is labeled "Backspace", then that's the one you
312 use for <Delback>. There may also be another key labeled "Delete"
313 somewhere else, but that's not <Delback>.
314
315 More generally, <Delback> deletes the character immediately before the
316 current cursor position.
317
318 >> Do this now--type a few characters, then delete them
319 by typing <Delback> a few times. Don't worry about this file
320 being changed; you will not alter the master tutorial. This is
321 your personal copy of it.
322
323 When a line of text gets too big for one line on the screen, the line
324 of text is "continued" onto a second screen line. A backslash ("\")
325 (or, if you're using a windowed display, a little curved arrow) at the
326 right margin indicates a line which has been continued.
327
328 >> Insert text until you reach the right margin, and keep on inserting.
329 You'll see a continuation line appear.
330
331 >> Use <Delback>s to delete the text until the line fits on one screen
332 line again. The continuation line goes away.
333
334 You can delete a Newline character just like any other character.
335 Deleting the Newline character between two lines merges them into
336 one line. If the resulting combined line is too long to fit in the
337 screen width, it will be displayed with a continuation line.
338
339 >> Move the cursor to the beginning of a line and type <Delback>. This
340 merges that line with the previous line.
341
342 >> Type <Return> to reinsert the Newline you deleted.
343
344 Remember that most Emacs commands can be given a repeat count;
345 this includes text characters. Repeating a text character inserts
346 it several times.
347
348 >> Try that now -- type C-u 8 * to insert ********.
349
350 You've now learned the most basic way of typing something in
351 Emacs and correcting errors. You can delete by words or lines
352 as well. Here is a summary of the delete operations:
353
354 <Delback> Delete the character just before the cursor
355 C-d Delete the next character after the cursor
356
357 M-<Delback> Kill the word immediately before the cursor
358 M-d Kill the next word after the cursor
359
360 C-k Kill from the cursor position to end of line
361 M-k Kill to the end of the current sentence
362
363 Notice that <Delback> and C-d vs M-<Delback> and M-d extend the parallel
364 started by C-f and M-f (well, <Delback> is not really a control
365 character, but let's not worry about that). C-k and M-k are like C-e
366 and M-e, sort of, in that lines are opposite sentences.
367
368 You can also kill any part of the text with one uniform method. Move
369 to one end of that part, and type C-@ or C-<SPC> (either one). (<SPC>
370 is the Space bar.) Move to the other end of that part, and type C-w.
371 That kills all the text between the two positions.
372
373 >> Move the cursor to the Y at the start of the previous paragraph.
374 >> Type C-<SPC>. Emacs should display a message "Mark set"
375 at the bottom of the screen.
376 >> Move the cursor to the n in "end", on the second line of the
377 paragraph.
378 >> Type C-w. This will kill the text starting from the Y,
379 and ending just before the n.
380
381 The difference between "killing" and "deleting" is that "killed" text
382 can be reinserted, whereas "deleted" things cannot be reinserted.
383 Reinsertion of killed text is called "yanking". Generally, the
384 commands that can remove a lot of text kill the text (they set up so
385 that you can yank the text), while the commands that remove just one
386 character, or only remove blank lines and spaces, do deletion (so you
387 cannot yank that text). <Delback> and C-d do deletion in the simplest
388 case, with no argument. When given an argument, they kill instead.
389
390 >> Move the cursor to the beginning of a line which is not empty.
391 Then type C-k to kill the text on that line.
392 >> Type C-k a second time. You'll see that it kills the Newline
393 which follows that line.
394
395 Note that a single C-k kills the contents of the line, and a second
396 C-k kills the line itself, and makes all the other lines move up. C-k
397 treats a numeric argument specially: it kills that many lines AND
398 their contents. This is not mere repetition. C-u 2 C-k kills two
399 lines and their newlines; typing C-k twice would not do that.
400
401 Bringing back killed text is called "yanking". (Think of it as
402 yanking back, or pulling back, some text that was taken away.) You
403 can yank the killed text either at the same place where it was killed,
404 or at some other place in the text you are editing, or even in a
405 different file. You can yank the same text several times; that makes
406 multiple copies of it.
407
408 The command for yanking is C-y. It reinserts the last killed text,
409 at the current cursor position.
410
411 >> Try it; type C-y to yank the text back.
412
413 If you do several C-k's in a row, all of the killed text is saved
414 together, so that one C-y will yank all of the lines at once.
415
416 >> Do this now, type C-k several times.
417
418 Now to retrieve that killed text:
419
420 >> Type C-y. Then move the cursor down a few lines and type C-y
421 again. You now see how to copy some text.
422
423 What do you do if you have some text you want to yank back, and then
424 you kill something else? C-y would yank the more recent kill. But
425 the previous text is not lost. You can get back to it using the M-y
426 command. After you have done C-y to get the most recent kill, typing
427 M-y replaces that yanked text with the previous kill. Typing M-y
428 again and again brings in earlier and earlier kills. When you have
429 reached the text you are looking for, you do not have to do anything to
430 keep it. Just go on with your editing, leaving the yanked text where
431 it is.
432
433 If you M-y enough times, you come back to the starting point (the most
434 recent kill).
435
436 >> Kill a line, move around, kill another line.
437 Then do C-y to get back the second killed line.
438 Then do M-y and it will be replaced by the first killed line.
439 Do more M-y's and see what you get. Keep doing them until
440 the second kill line comes back, and then a few more.
441 If you like, you can try giving M-y positive and negative
442 arguments.
443
444
445 * UNDO
446 ------
447
448 If you make a change to the text, and then decide that it was a
449 mistake, you can undo the change with the undo command, C-x u.
450
451 Normally, C-x u undoes the changes made by one command; if you repeat
452 the C-x u several times in a row, each repetition undoes one
453 additional command.
454
455 But there are two exceptions: commands that do not change the text do
456 not count (this includes cursor motion commands and scrolling
457 command), and self-inserting characters are usually handled in groups
458 of up to 20. (This is to reduce the number of C-x u's you have to
459 type to undo insertion of text.)
460
461 >> Kill this line with C-k, then type C-x u and it should reappear.
462
463 C-_ is an alternative undo command; it works just the same as C-x u,
464 but it is easier to type several times in a row. The disadvantage of
465 C-_ is that on some keyboards it is not obvious how to type it. That
466 is why we provide C-x u as well. On some terminals, you can type C-_
467 by typing / while holding down CONTROL.
468
469 A numeric argument to C-_ or C-x u acts as a repeat count.
470
471 You can undo deletion of text just as you can undo killing of text.
472 The distinction between killing something and deleting it affects
473 whether you can yank it with C-y; it makes no difference for undo.
474
475
476 * FILES
477 -------
478
479 In order to make the text you edit permanent, you must put it in a
480 file. Otherwise, it will go away when your invocation of Emacs goes
481 away. In order to put your text in a file, you must "find" the file
482 before you enter the text. (This is also called "visiting" the file.)
483
484 Finding a file means that you see the contents of the file within
485 Emacs. In many ways, it is as if you were editing the file itself.
486 However, the changes you make using Emacs do not become permanent
487 until you "save" the file. This is so you can avoid leaving a
488 half-changed file on the system when you do not want to. Even when
489 you save, Emacs leaves the original file under a changed name in case
490 you later decide that your changes were a mistake.
491
492 If you look near the bottom of the screen you will see a line that
493 begins and ends with dashes, and starts with "--:-- TUTORIAL" or
494 something like that. This part of the screen normally shows the name
495 of the file that you are visiting. Right now, you are visiting a file
496 called "TUTORIAL" which is your personal scratch copy of the Emacs
497 tutorial. When you find a file with Emacs, that file's name will
498 appear in that precise spot.
499
500 One special thing about the command for finding a file is that you
501 have to say what file name you want. We say the command "reads an
502 argument from the terminal" (in this case, the argument is the name of
503 the file). After you type the command
504
505 C-x C-f Find a file
506
507 Emacs asks you to type the file name. The file name you type appears
508 on the bottom line of the screen. The bottom line is called the
509 minibuffer when it is used for this sort of input. You can use
510 ordinary Emacs editing commands to edit the file name.
511
512 While you are entering the file name (or any minibuffer input),
513 you can cancel the command with C-g.
514
515 >> Type C-x C-f, then type C-g. This cancels the minibuffer,
516 and also cancels the C-x C-f command that was using the
517 minibuffer. So you do not find any file.
518
519 When you have finished entering the file name, type <Return> to
520 terminate it. Then C-x C-f command goes to work, and finds the file
521 you chose. The minibuffer disappears when the C-x C-f command is
522 finished.
523
524 In a little while the file contents appear on the screen, and you can
525 edit the contents. When you wish to make your changes permanent,
526 type the command
527
528 C-x C-s Save the file
529
530 This copies the text within Emacs into the file. The first time you
531 do this, Emacs renames the original file to a new name so that it is
532 not lost. The new name is made by adding "~" to the end of the
533 original file's name.
534
535 When saving is finished, Emacs displays the name of the file written.
536 You should save fairly often, so that you will not lose very much
537 work if the system should crash.
538
539 >> Type C-x C-s, saving your copy of the tutorial.
540 This should show "Wrote ...TUTORIAL" at the bottom of the screen.
541
542 You can find an existing file, to view it or edit it. You can also
543 find a file which does not already exist. This is the way to create a
544 file with Emacs: find the file, which will start out empty, and then
545 begin inserting the text for the file. When you ask to "save" the
546 file, Emacs will really create the file with the text that you have
547 inserted. From then on, you can consider yourself to be editing an
548 already existing file.
549
550
551 * BUFFERS
552 ---------
553
554 If you find a second file with C-x C-f, the first file remains
555 inside Emacs. You can switch back to it by finding it again with
556 C-x C-f. This way you can get quite a number of files inside Emacs.
557
558 >> Create a file named "foo" by typing C-x C-f foo <Return>.
559 Then insert some text, edit it, and save "foo" by typing C-x C-s.
560 Finally, type C-x C-f TUTORIAL <Return>
561 to come back to the tutorial.
562
563 Emacs stores each file's text inside an object called a "buffer".
564 Finding a file makes a new buffer inside Emacs. To see a list of the
565 buffers that currently exist in your Emacs job, type
566
567 C-x C-b List buffers
568
569 >> Try C-x C-b now.
570
571 See how each buffer has a name, and it may also have a file name for
572 the file whose contents it holds. ANY text you see in an Emacs window
573 is always part of some buffer.
574
575 >> Type C-x 1 to get rid of the buffer list.
576
577 When you have several buffers, only one of them is "current" at any
578 time. That buffer is the one you edit. If you want to edit another
579 buffer, you need to "switch" to it. If you want to switch to a buffer
580 that corresponds to a file, you can do it by visiting the file again
581 with C-x C-f. But there is an easier way: use the C-x b command.
582 In that command, you have to type the buffer's name.
583
584 >> Type C-x b foo <Return> to go back to the buffer "foo" which holds
585 the text of the file "foo". Then type C-x b TUTORIAL <Return>
586 to come back to this tutorial.
587
588 Most of the time, the buffer's name is the same as the file name
589 (without the file directory part). However, this is not always true.
590 The buffer list you make with C-x C-b always shows you the name of
591 every buffer.
592
593 ANY text you see in an Emacs window is always part of some buffer.
594 Some buffers do not correspond to files. For example, the buffer
595 named "*Buffer List*" does not have any file. It is the buffer which
596 contains the buffer list that you made with C-x C-b. The buffer named
597 "*Messages*" also does not correspond to any file; it contains the
598 messages that have appeared on the bottom line during your Emacs
599 session.
600
601 >> Type C-x b *Messages* <Return> to look at the buffer of messages.
602 Then type C-x b TUTORIAL <Return> to come back to this tutorial.
603
604 If you make changes to the text of one file, then find another file,
605 this does not save the first file. Its changes remain inside Emacs,
606 in that file's buffer. The creation or editing of the second file's
607 buffer has no effect on the first file's buffer. This is very useful,
608 but it also means that you need a convenient way to save the first
609 file's buffer. It would be a nuisance to have to switch back to
610 it with C-x C-f in order to save it with C-x C-s. So we have
611
612 C-x s Save some buffers
613
614 C-x s asks you about each buffer which contains changes that you have
615 not saved. It asks you, for each such buffer, whether to save the
616 buffer.
617
618 >> Insert a line of text, then type C-x s.
619 It should ask you whether to save the buffer named TUTORIAL.
620 Answer yes to the question by typing "y".
621
622
623 * EXTENDING THE COMMAND SET
624 ---------------------------
625
626 There are many, many more Emacs commands than could possibly be put
627 on all the control and meta characters. Emacs gets around this with
628 the X (eXtend) command. This comes in two flavors:
629
630 C-x Character eXtend. Followed by one character.
631 M-x Named command eXtend. Followed by a long name.
632
633 These are commands that are generally useful but used less than the
634 commands you have already learned about. You have already seen a few
635 of them: the file commands C-x C-f to Find and C-x C-s to Save, for
636 example. Another example is the command to end the Emacs
637 session--this is the command C-x C-c. (Do not worry about losing
638 changes you have made; C-x C-c offers to save each changed file before
639 it kills the Emacs.)
640
641 If you are using a graphical display that supports multiple
642 applications in parallel, you don't need any special command to move
643 from Emacs to another application. You can do this with the mouse or
644 with window manager commands. However, if you're using a text
645 terminal which can only show one application at a time, you need to
646 "suspend" Emacs to move to any other program.
647
648 C-z is the command to exit Emacs *temporarily*--so that you can go
649 back to the same Emacs session afterward. When Emacs is running on a
650 text terminal, C-z "suspends" Emacs; that is, it returns to the shell
651 but does not destroy the Emacs. In the most common shells, you can
652 resume Emacs with the `fg' command or with `%emacs'.
653
654 The time to use C-x C-c is when you are about to log out. It's also
655 the right thing to use to exit an Emacs invoked under mail handling
656 programs and other miscellaneous utilities, since they may not know
657 how to cope with suspension of Emacs. In ordinary circumstances,
658 though, if you are not about to log out, it is better to suspend Emacs
659 with C-z instead of exiting Emacs.
660
661 There are many C-x commands. Here is a list of the ones you have learned:
662
663 C-x C-f Find file
664 C-x C-s Save file
665 C-x s Save some buffers
666 C-x C-b List buffers
667 C-x b Switch buffer
668 C-x C-c Quit Emacs
669 C-x 1 Delete all but one window
670 C-x u Undo
671
672 Named eXtended commands are commands which are used even less
673 frequently, or commands which are used only in certain modes. An
674 example is the command replace-string, which globally replaces one
675 string with another. When you type M-x, Emacs prompts you at the
676 bottom of the screen with M-x and you should type the name of the
677 command; in this case, "replace-string". Just type "repl s<TAB>" and
678 Emacs will complete the name. (<TAB> is the Tab key, usually found
679 above the CapsLock or Shift key near the left edge of the keyboard.)
680 End the command name with <Return>.
681
682 The replace-string command requires two arguments--the string to be
683 replaced, and the string to replace it with. You must end each
684 argument with <Return>.
685
686 >> Move the cursor to the blank line two lines below this one.
687 Then type M-x repl s<Return>changed<Return>altered<Return>.
688
689 Notice how this line has changed: you've replaced
690 the word c-h-a-n-g-e-d with "altered" wherever it occurred,
691 after the initial position of the cursor.
692
693
694 * AUTO SAVE
695 -----------
696
697 When you have made changes in a file, but you have not saved them yet,
698 they could be lost if your computer crashes. To protect you from
699 this, Emacs periodically writes an "auto save" file for each file that
700 you are editing. The auto save file name has a # at the beginning and
701 the end; for example, if your file is named "hello.c", its auto save
702 file's name is "#hello.c#". When you save the file in the normal way,
703 Emacs deletes its auto save file.
704
705 If the computer crashes, you can recover your auto-saved editing by
706 finding the file normally (the file you were editing, not the auto
707 save file) and then typing M-x recover file<Return>. When it asks for
708 confirmation, type yes<Return> to go ahead and recover the auto-save
709 data.
710
711
712 * ECHO AREA
713 -----------
714
715 If Emacs sees that you are typing multicharacter commands slowly, it
716 shows them to you at the bottom of the screen in an area called the
717 "echo area". The echo area contains the bottom line of the screen.
718
719
720 * MODE LINE
721 -----------
722
723 The line immediately above the echo area is called the "mode line".
724 The mode line says something like this:
725
726 --:** TUTORIAL 63% L749 (Fundamental)-----------------------
727
728 This line gives useful information about the status of Emacs and
729 the text you are editing.
730
731 You already know what the filename means--it is the file you have
732 found. NN% indicates your current position in the text; it means that
733 NN percent of the text is above the top of the screen. If the top of
734 the file is on the screen, it will say "Top" instead of " 0%". If the
735 bottom of the text is on the screen, it will say "Bot". If you are
736 looking at text so small that all of it fits on the screen, the mode
737 line says "All".
738
739 The L and digits indicate position in another way: they give the
740 current line number of point.
741
742 The stars near the front mean that you have made changes to the text.
743 Right after you visit or save a file, that part of the mode line shows
744 no stars, just dashes.
745
746 The part of the mode line inside the parentheses is to tell you what
747 editing modes you are in. The default mode is Fundamental which is
748 what you are using now. It is an example of a "major mode".
749
750 Emacs has many different major modes. Some of them are meant for
751 editing different languages and/or kinds of text, such as Lisp mode,
752 Text mode, etc. At any time one and only one major mode is active,
753 and its name can always be found in the mode line just where
754 "Fundamental" is now.
755
756 Each major mode makes a few commands behave differently. For example,
757 there are commands for creating comments in a program, and since each
758 programming language has a different idea of what a comment should
759 look like, each major mode has to insert comments differently. Each
760 major mode is the name of an extended command, which is how you can
761 switch to that mode. For example, M-x fundamental-mode is a command to
762 switch to Fundamental mode.
763
764 If you are going to be editing human-language text, such as this file, you
765 should probably use Text Mode.
766
767 >> Type M-x text mode<Return>.
768
769 Don't worry, none of the Emacs commands you have learned changes in
770 any great way. But you can observe that M-f and M-b now treat
771 apostrophes as part of words. Previously, in Fundamental mode,
772 M-f and M-b treated apostrophes as word-separators.
773
774 Major modes usually make subtle changes like that one: most commands
775 do "the same job" in each major mode, but they work a little bit
776 differently.
777
778 To view documentation on your current major mode, type C-h m.
779
780 >> Use C-u C-v once or more to bring this line near the top of screen.
781 >> Type C-h m, to see how Text mode differs from Fundamental mode.
782 >> Type C-x 1 to remove the documentation from the screen.
783
784 Major modes are called major because there are also minor modes.
785 Minor modes are not alternatives to the major modes, just minor
786 modifications of them. Each minor mode can be turned on or off by
787 itself, independent of all other minor modes, and independent of your
788 major mode. So you can use no minor modes, or one minor mode, or any
789 combination of several minor modes.
790
791 One minor mode which is very useful, especially for editing
792 human-language text, is Auto Fill mode. When this mode is on, Emacs
793 breaks the line in between words automatically whenever you insert
794 text and make a line that is too wide.
795
796 You can turn Auto Fill mode on by doing M-x auto fill mode<Return>.
797 When the mode is on, you can turn it off again by doing M-x
798 auto fill mode<Return>. If the mode is off, this command turns it on,
799 and if the mode is on, this command turns it off. We say that the
800 command "toggles the mode".
801
802 >> Type M-x auto fill mode<Return> now. Then insert a line of "asdf "
803 over again until you see it divide into two lines. You must put in
804 spaces between them because Auto Fill breaks lines only at spaces.
805
806 The margin is usually set at 70 characters, but you can change it
807 with the C-x f command. You should give the margin setting you want
808 as a numeric argument.
809
810 >> Type C-x f with an argument of 20. (C-u 2 0 C-x f).
811 Then type in some text and see Emacs fill lines of 20
812 characters with it. Then set the margin back to 70 using
813 C-x f again.
814
815 If you make changes in the middle of a paragraph, Auto Fill mode
816 does not re-fill it for you.
817 To re-fill the paragraph, type M-q (META-q) with the cursor inside
818 that paragraph.
819
820 >> Move the cursor into the previous paragraph and type M-q.
821
822
823 * SEARCHING
824 -----------
825
826 Emacs can do searches for strings (these are groups of contiguous
827 characters or words) either forward through the text or backward
828 through it. Searching for a string is a cursor motion command;
829 it moves the cursor to the next place where that string appears.
830
831 The Emacs search command is different from the search commands
832 of most editors, in that it is "incremental". This means that the
833 search happens while you type in the string to search for.
834
835 The command to initiate a search is C-s for forward search, and C-r
836 for reverse search. BUT WAIT! Don't try them now.
837
838 When you type C-s you'll notice that the string "I-search" appears as
839 a prompt in the echo area. This tells you that Emacs is in what is
840 called an incremental search waiting for you to type the thing that
841 you want to search for. <Return> terminates a search.
842
843 >> Now type C-s to start a search. SLOWLY, one letter at a time,
844 type the word 'cursor', pausing after you type each
845 character to notice what happens to the cursor.
846 Now you have searched for "cursor", once.
847 >> Type C-s again, to search for the next occurrence of "cursor".
848 >> Now type <Delback> four times and see how the cursor moves.
849 >> Type <Return> to terminate the search.
850
851 Did you see what happened? Emacs, in an incremental search, tries to
852 go to the occurrence of the string that you've typed out so far. To
853 go to the next occurrence of 'cursor' just type C-s again. If no such
854 occurrence exists, Emacs beeps and tells you the search is currently
855 "failing". C-g would also terminate the search.
856
857 NOTE: On some systems, typing C-s will freeze the screen and you will
858 see no further output from Emacs. This indicates that an operating
859 system "feature" called "flow control" is intercepting the C-s and not
860 letting it get through to Emacs. To unfreeze the screen, type C-q.
861 Then see the section "Spontaneous Entry to Incremental Search" in the
862 Emacs manual for advice on dealing with this "feature".
863
864 If you are in the middle of an incremental search and type <Delback>,
865 you'll notice that the last character in the search string is erased
866 and the search backs up to the last place of the search. For
867 instance, suppose you have typed "c", to search for the first
868 occurrence of "c". Now if you type "u", the cursor will move
869 to the first occurrence of "cu". Now type <Delback>. This erases
870 the "u" from the search string, and the cursor moves back to
871 the first occurrence of "c".
872
873 If you are in the middle of a search and type a control or meta
874 character (with a few exceptions--characters that are special in
875 a search, such as C-s and C-r), the search is terminated.
876
877 The C-s starts a search that looks for any occurrence of the search
878 string AFTER the current cursor position. If you want to search for
879 something earlier in the text, type C-r instead. Everything that we
880 have said about C-s also applies to C-r, except that the direction of
881 the search is reversed.
882
883
884 * MULTIPLE WINDOWS
885 ------------------
886
887 One of the nice features of Emacs is that you can display more than one
888 window on the screen at the same time.
889
890 >> Move the cursor to this line and type C-u 0 C-l (that's CONTROL-L, not
891 CONTROL-1).
892
893 >> Now type C-x 2 which splits the screen into two windows.
894 Both windows display this tutorial. The cursor stays in the top window.
895
896 >> Type C-M-v to scroll the bottom window.
897 (If you do not have a real META key, type <ESC> C-v.)
898
899 >> Type C-x o ("o" for "other") to move the cursor to the bottom window.
900 >> Use C-v and M-v in the bottom window to scroll it.
901 Keep reading these directions in the top window.
902
903 >> Type C-x o again to move the cursor back to the top window.
904 The cursor in the top window is just where it was before.
905
906 You can keep using C-x o to switch between the windows. Each
907 window has its own cursor position, but only one window actually
908 shows the cursor. All the ordinary editing commands apply to the
909 window that the cursor is in. We call this the "selected window".
910
911 The command C-M-v is very useful when you are editing text in one
912 window and using the other window just for reference. You can keep
913 the cursor always in the window where you are editing, and advance
914 through the other window sequentially with C-M-v.
915
916 C-M-v is an example of a CONTROL-META character. If you have a real
917 META key, you can type C-M-v by holding down both CONTROL and META while
918 typing v. It does not matter whether CONTROL or META "comes first,"
919 because both of these keys act by modifying the characters you type.
920
921 If you do not have a real META key, and you use <ESC> instead, the
922 order does matter: you must type <ESC> followed by CONTROL-v, because
923 CONTROL-<ESC> v will not work. This is because <ESC> is a character
924 in its own right, not a modifier key.
925
926 >> Type C-x 1 (in the top window) to get rid of the bottom window.
927
928 (If you had typed C-x 1 in the bottom window, that would get rid
929 of the top one. Think of this command as "Keep just one
930 window--the window I am already in.")
931
932 You do not have to display the same buffer in both windows. If you
933 use C-x C-f to find a file in one window, the other window does not
934 change. You can find a file in each window independently.
935
936 Here is another way to use two windows to display two different
937 things:
938
939 >> Type C-x 4 C-f followed by the name of one of your files.
940 End with <Return>. See the specified file appear in the bottom
941 window. The cursor goes there, too.
942
943 >> Type C-x o to go back to the top window, and C-x 1 to delete
944 the bottom window.
945
946
947 * RECURSIVE EDITING LEVELS
948 --------------------------
949
950 Sometimes you will get into what is called a "recursive editing
951 level". This is indicated by square brackets in the mode line,
952 surrounding the parentheses around the major mode name. For
953 example, you might see [(Fundamental)] instead of (Fundamental).
954
955 To get out of the recursive editing level, type <ESC> <ESC> <ESC>.
956 That is an all-purpose "get out" command. You can also use it for
957 eliminating extra windows, and getting out of the minibuffer.
958
959 >> Type M-x to get into a minibuffer; then type <ESC> <ESC> <ESC> to
960 get out.
961
962 You cannot use C-g to get out of a recursive editing level. This is
963 because C-g is used for canceling commands and arguments WITHIN the
964 recursive editing level.
965
966
967 * GETTING MORE HELP
968 -------------------
969
970 In this tutorial we have tried to supply just enough information to
971 get you started using Emacs. There is so much available in Emacs that
972 it would be impossible to explain it all here. However, you may want
973 to learn more about Emacs since it has many other useful features.
974 Emacs provides commands for reading documentation about Emacs
975 commands. These "help" commands all start with the character
976 CONTROL-h, which is called "the Help character".
977
978 To use the Help features, type the C-h character, and then a
979 character saying what kind of help you want. If you are REALLY lost,
980 type C-h ? and Emacs will tell you what kinds of help it can give.
981 If you have typed C-h and decide you do not want any help, just
982 type C-g to cancel it.
983
984 (Some sites change the meaning of the character C-h. They really
985 should not do this as a blanket measure for all users, so you have
986 grounds to complain to the system administrator. Meanwhile, if C-h
987 does not display a message about help at the bottom of the screen, try
988 typing the F1 key or M-x help <Return> instead.)
989
990 The most basic HELP feature is C-h c. Type C-h, the character c, and
991 a command character or sequence; then Emacs displays a very brief
992 description of the command.
993
994 >> Type C-h c C-p.
995
996 The message should be something like this:
997
998 C-p runs the command previous-line
999
1000 This tells you the "name of the function". Function names are used
1001 mainly for customizing and extending Emacs. But since function names
1002 are chosen to indicate what the command does, they can serve also as
1003 very brief documentation--sufficient to remind you of commands you
1004 have already learned.
1005
1006 Multi-character commands such as C-x C-s and (if you have no META or
1007 EDIT or ALT key) <ESC>v are also allowed after C-h c.
1008
1009 To get more information about a command, use C-h k instead of C-h c.
1010
1011 >> Type C-h k C-p.
1012
1013 This displays the documentation of the function, as well as its
1014 name, in an Emacs window. When you are finished reading the
1015 output, type C-x 1 to get rid of the help text. You do not have
1016 to do this right away. You can do some editing while referring
1017 to the help text, and then type C-x 1.
1018
1019 Here are some other useful C-h options:
1020
1021 C-h f Describe a function. You type in the name of the
1022 function.
1023
1024 >> Try typing C-h f previous-line<Return>.
1025 This displays all the information Emacs has about the
1026 function which implements the C-p command.
1027
1028 A similar command C-h v displays the documentation of variables whose
1029 values you can set to customize Emacs behavior. You need to type in
1030 the name of the variable when Emacs prompts for it.
1031
1032 C-h a Command Apropos. Type in a keyword and Emacs will list
1033 all the commands whose names contain that keyword.
1034 These commands can all be invoked with META-x.
1035 For some commands, Command Apropos will also list a one
1036 or two character sequence which runs the same command.
1037
1038 >> Type C-h a file<Return>.
1039
1040 This displays in another window a list of all M-x commands with "file"
1041 in their names. You will see character-commands like C-x C-f listed
1042 beside the corresponding command names such as find-file.
1043
1044 >> Type C-M-v to scroll the help window. Do this a few times.
1045
1046 >> Type C-x 1 to delete the help window.
1047
1048 C-h i Read On-line Manuals (a.k.a. Info). This command puts
1049 you into a special buffer called `*info*' where you
1050 can read on-line manuals for the packages installed on
1051 your system. Type m emacs <Return> to read the Emacs
1052 manual. If you have never before used Info, type ?
1053 and Emacs will take you on a guided tour of Info mode
1054 facilities. Once you are through with this tutorial,
1055 you should consult the Emacs Info manual as your
1056 primary documentation.
1057
1058
1059 * MORE FEATURES
1060 ---------------
1061
1062 You can learn more about Emacs by reading its manual, either as a book
1063 or on-line in Info (use the Help menu or type F10 h r). Two features
1064 that you may like especially are completion, which saves typing, and
1065 dired, which simplifies file handling.
1066
1067 Completion is a way to avoid unnecessary typing. For instance, if you
1068 want to switch to the *Messages* buffer, you can type C-x b *M<Tab>
1069 and Emacs will fill in the rest of the buffer name as far as it can
1070 determine from what you have already typed. Completion is described
1071 in Info in the Emacs manual in the node called "Completion".
1072
1073 Dired enables you to list files in a directory (and optionally its
1074 subdirectories), move around that list, visit, rename, delete and
1075 otherwise operate on the files. Dired is described in Info in the
1076 Emacs manual in the node called "Dired".
1077
1078 The manual also describes many other Emacs features.
1079
1080
1081 * CONCLUSION
1082 ------------
1083
1084 Remember, to exit Emacs permanently use C-x C-c. To exit to a shell
1085 temporarily, so that you can come back to Emacs afterward, use C-z.
1086
1087 This tutorial is meant to be understandable to all new users, so if
1088 you found something unclear, don't sit and blame yourself - complain!
1089
1090
1091 * COPYING
1092 ---------
1093
1094 This tutorial descends from a long line of Emacs tutorials
1095 starting with the one written by Stuart Cracraft for the original Emacs.
1096
1097 This version of the tutorial is a part of GNU Emacs. It is copyrighted
1098 and comes with permission to distribute copies on certain conditions:
1099
1100 Copyright (C) 1985, 1996, 1998, 2001, 2002, 2003, 2004, 2005, 2006,
1101 2007, 2008 Free Software Foundation, Inc.
1102
1103 This file is part of GNU Emacs.
1104
1105 GNU Emacs is free software: you can redistribute it and/or modify
1106 it under the terms of the GNU General Public License as published by
1107 the Free Software Foundation, either version 3 of the License, or
1108 (at your option) any later version.
1109
1110 GNU Emacs is distributed in the hope that it will be useful,
1111 but WITHOUT ANY WARRANTY; without even the implied warranty of
1112 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1113 GNU General Public License for more details.
1114
1115 You should have received a copy of the GNU General Public License
1116 along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
1117
1118 Please read the file COPYING and then do give copies of GNU Emacs to
1119 your friends. Help stamp out software obstructionism ("ownership") by
1120 using, writing, and sharing free software!
1121
1122 ;;; arch-tag: a0f84628-777f-4238-8865-451a73167f55