emacs / etc / TUTORIAL

   1
   2
   3
   4
   5
   6
   7
   8
   9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
  24
  25
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60
  61
  62
  63
  64
  65
  66
  67
  68
  69
  70
  71
  72
  73
  74
  75
  76
  77
  78
  79
  80
  81
  82
  83
  84
  85
  86
  87
  88
  89
  90
  91
  92
  93
  94
  95
  96
  97
  98
  99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 286
 287
 288
 289
 290
 291
 292
 293
 294
 295
 296
 297
 298
 299
 300
 301
 302
 303
 304
 305
 306
 307
 308
 309
 310
 311
 312
 313
 314
 315
 316
 317
 318
 319
 320
 321
 322
 323
 324
 325
 326
 327
 328
 329
 330
 331
 332
 333
 334
 335
 336
 337
 338
 339
 340
 341
 342
 343
 344
 345
 346
 347
 348
 349
 350
 351
 352
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364
 365
 366
 367
 368
 369
 370
 371
 372
 373
 374
 375
 376
 377
 378
 379
 380
 381
 382
 383
 384
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
Copyright (c) 1985 Free Software Foundation, Inc;  See end for conditions.
You are looking at the Emacs tutorial.

Emacs commands generally involve the CONTROL key (sometimes labeled
CTRL or CTL) or the META key (sometimes labeled EDIT or ALT).  Rather than
write that in full each time, we'll use the following abbreviations:

 C-<chr>  means hold the CONTROL key while typing the character <chr>
	  Thus, C-f would be: hold the CONTROL key and type f.
 M-<chr>  means hold the META or EDIT or ALT key down while typing <chr>.
	  If there is no META, EDIT or ALT key, instead press and release the
	  ESC key and then type <chr>.  We write <ESC> for the ESC key.

Important note: to end the Emacs session, type C-x C-c.  (Two characters.)
The characters ">>" at the left margin indicate directions for you to
try using a command.  For instance:
<<Blank lines inserted here by startup of help-with-tutorial>>
>>  Now type C-v (View next screen) to move to the next screen.
	(go ahead, do it by holding down the control key while typing v).
	From now on, you should do this again whenever you finish
	reading the screen.

Note that there is an overlap of two lines when you move from screen
to screen; this provides some continuity so you can continue reading
the text.

The first thing that you need to know is how to move around from place
to place in the text.  You already know how to move forward one screen,
with C-v.  To move backwards one screen, type M-v (hold down the META key
and type v, or type <ESC>v if you do not have a META, EDIT, or ALT key).

>>  Try typing M-v and then C-v, a few times.


* SUMMARY
---------

The following commands are useful for viewing screenfuls:

	C-v	Move forward one screenful
	M-v	Move backward one screenful
	C-l	Clear screen and redisplay all the text,
		 moving the text around the cursor
		 to the center of the screen.
		 (That's control-L, not control-1.)

>> Find the cursor, and note what text is near it.
   Then type C-l.
   Find the cursor again and notice that the same text
   is near the cursor now.


* BASIC CURSOR CONTROL
----------------------

Moving from screenful to screenful is useful, but how do you
move to a specific place within the text on the screen?

There are several ways you can do this.  The most basic way is to use
the commands C-p, C-b, C-f, and C-n.  Each of these commands moves the
cursor one row or column in a particular direction on the screen.
Here is a table showing these four commands and shows the directions
they move:
 
			  Previous line, C-p
				  :
				  :
   Backward, C-b .... Current cursor position .... Forward, C-f
				  :
				  :
			    Next line, C-n

>> Move the cursor to the line in the middle of that diagram
   using C-n or C-p.  Then type C-l to see the whole diagram
   centered in the screen.

You'll probably find it easy to think of these by letter: P for
previous, N for next, B for backward and F for forward.  These are the
basic cursor positioning commands, and you'll be using them ALL the
time, so it would be of great benefit if you learn them now.

>> Do a few C-n's to bring the cursor down to this line.

>> Move into the line with C-f's and then up with C-p's.
   See what C-p does when the cursor is in the middle of the line.

Each of text line ends with a Newline character, which serves to
separate it from the following line.  The last line in your file ought
to have a Newline at the end (but Emacs does not require it to have
one).

>> Try to C-b at the beginning of a line.  It should move to
   the end of the previous line.  This is because it moves back
   across the Newline character.

C-f can move across a Newline just like C-b.

>> Do a few more C-b's, so you get a feel for where the cursor is.
   Then do C-f's to return to the end of the line.
   Then do one more C-f to move to the following line.

When you move past the top or bottom of the screen, the text beyond
the edge shifts onto the screen.  This is called "scrolling".  It
enables Emacs to move the cursor to the specified place in the text
without moving it off the screen.

>> Try to move the cursor off the bottom of the screen with C-n, and
   see what happens.

If moving by characters is too slow, you can move by words.  M-f
(Meta-f) moves forward a word and M-b moves back a word.

>> Type a few M-f's and M-b's.

When you are in the middle of a word, M-f moves to the end of the word.
When you are in whitespace between words, M-f moves to the end of the
following word.  M-b works likewise in the opposite direction.

>> Type M-f and M-b a few times, interspersed with C-f's and C-b's
   so that you can observe the action of M-f and M-b from various
   places inside and between words.

Notice the parallel between C-f and C-b on the one hand, and M-f and
M-b on the other hand.  Very often Meta characters are used for
operations related to the units defined by language (words, sentences,
paragraphs), while Control characters operate on basic units that are
independent of what you are editing (characters, lines, etc).

This parallel applies between lines and sentences: C-a and C-e move to
the beginning or end of a line, and M-a and M-e move to the beginning
or end of a sentence.

>> Try a couple of C-a's, and then a couple of C-e's.
   Try a couple of M-a's, and then a couple of M-e's.

See how repeated C-a's do nothing, but repeated M-a's keep moving one
more sentence.  Although these are not quite analogous, each one seems
natural.

The location of the cursor in the text is also called "point".  To
paraphrase, the cursor shows on the screen where point is located in
the text.

Here is a summary of simple cursor-moving operations, including the
word and sentence moving commands:

	C-f	Move forward a character
	C-b	Move backward a character

	M-f	Move forward a word
	M-b	Move backward a word

	C-n	Move to next line
	C-p	Move to previous line

	C-a	Move to beginning of line
	C-e	Move to end of line

	M-a	Move back to beginning of sentence
	M-e	Move forward to end of sentence

>> Try all of these commands now a few times for practice.
   These are the most often used commands.

Two other important cursor motion commands are M-< (Meta Less-than),
which moves to the beginning of the whole text, and M-> (Meta
Greater-than), which moves to the end of the whole text.

On most terminals, the "<" is above the comma, so you must use the
shift key to type it.  On these terminals you must use the shift key
to type M-< also; without the shift key, you would be typing M-comma.

>> Try M-< now, to move to the beginning of the tutorial.
   Then use C-v repeatedly to move back here.

>> Try M-> now, to move to the end of the tutorial.
   Then use M-v repeatedly to move back here.

You can also move the cursor with the arrow keys, if your terminal has
arrow keys.  We recommend learning C-b, C-f, C-n and C-p for three
reasons.  First, they work on all kinds of terminals.  Second, once
you gain practice at using Emacs, you will find that typing these Control
characters is faster than typing the arrow keys (because you do not
have to move your hands away from touch-typing position).  Third, once
you form the habit of using these Control character commands, you can
easily learn to use other advanced cursor motion commands as well.

Most Emacs commands accept a numeric argument; for most commands, this
serves as a repeat-count.  The way you give a command a repeat count
is by typing C-u and then the digits before you type the command.  If
you have a META (or EDIT or ALT) key, there is another alternative way
to enter a numeric argument: type the digits while holding down the
META key.  We recommend learning the C-u method because it works on
any terminal.

For instance, C-u 8 C-f moves forward eight characters.
	
>> Try using C-n or C-p with a numeric argument, to move the cursor
   to a line near this one with just one command.

Most commands use the numeric argument as a repeat count.  Certain
exceptional commands use it differently.  C-v and M-v are among the
exceptions.  When given an argument, they scroll the screen up or down
by that many lines, rather than by a screenfuls.  For example, C-u 4
C-v scrolls the screen by 4 lines.

>> Try typing C-u 8 C-v now.

This should have scrolled the screen up by 8 lines.  If you would like
to scroll it down again, you can give an argument to M-v.

If you are using X Windows, there should be a tall rectangular area
called a scroll bar at the left hand side of the Emacs window.  You
can scroll the text by clicking the mouse in the scroll bar.

>> Try pressing the middle button at the top of the highlighted area
   within the scroll bar.  This should scroll the text to a position
   determined by how high or low you click.

>> Try moving the mouse up and down, while holding the middle button
   pressed down.  You'll see that the text scrolls up and down as
   you move the mouse.


* WHEN EMACS IS HUNG
--------------------

If Emacs stops responding to your commands, you can stop it safely by
typing C-g.  You can use C-g to stop a command which is taking too
long to execute.

You can also use C-g to discard a numeric argument or the beginning of
a command that you do not want to finish.

>> Type C-u 100 to make a numeric arg of 100, then type C-g.
   Now type C-f.  It should move just one character,
   because you canceled the argument with C-g.

If you have typed an <ESC> by mistake, you can get rid of it
with a C-g.


* DISABLED COMMANDS
-------------------

Some Emacs commands are "disabled" so that beginning users cannot use
them by accident.

If you type one of the disabled commands, Emacs displays a message
saying what the command was, and asking you whether you want to go
ahead and execute the command.

If you really want to try the command, type Space in answer to the
question.  Normally, if you do not want to execute the disabled
command, answer the question with "n".

>> Type <ESC> : (which is a disabled command),
   then type n to answer the question.


* WINDOWS
---------

Emacs can have several windows, each displaying its own text.  We will
explain later on how to use multiple windows.  Right now we want to
explain how to get rid of extra windows and go back to basic
one-window editing.  It is simple:

	C-x 1	One window (i.e., kill all other windows).

That is Control-x followed by the digit 1.  C-x 1 expands the window
which contains the cursor, to occupy the full screen.  It deletes all
other windows.

>> Move the cursor to this line and type C-u 0 C-l.
>> Type Control-h k Control-f.
   See how this window shrinks, while a new one appears
   to display documentation on the Control-f command.

>> Type C-x 1 and see the documentation listing window disappear.

This command is unlike the other commands you have learned in that it
consists of two characters.  It starts with the character Control-x.
There is a whole series of commands that start with Control-x; many of
them have to do with windows, files, buffers, and related things.
These commands are two, three or four characters long.


* INSERTING AND DELETING
------------------------

If you want to insert text, just type the text.  Characters which you
can see, such as A, 7, *, etc. are taken by Emacs as text and inserted
immediately.  Type <Return> (the carriage-return key) to insert a
Newline character.

You can delete the last character you typed by typing <Delete>.
<Delete> is a key on the keyboard, which may be labeled "Del".  In
some cases, the "Backspace" key serves as <Delete>, but not always!

More generally, <Delete> deletes the character immediately before the
current cursor position.

>> Do this now--type a few characters, then delete them
   by typing <Delete> a few times.  Don't worry about this file
   being changed; you will not alter the master tutorial.  This is
   your personal copy of it.

When a line of text gets too big for one line on the screen, the line
of text is "continued" onto a second screen line.  A backslash ("\")
at the right margin indicates a line which has been continued.

>> Insert text until you reach the right margin, and keep on inserting.
   You'll see a continuation line appear.

>> Use <Delete>s to delete the text until the line fits on one screen
   line again.  The continuation line goes away.

You can delete a Newline character just like any other character.
Deleting the Newline character between two lines merges them into
one line.  If the resulting combined line is too long to fit in the
screen width, it will be displayed with a continuation line.

>> Move the cursor to the beginning of a line and type <Delete>.  This
   merges that line with the previous line.

>> Type <Return> to reinsert the Newline you deleted.

Remember that most Emacs commands can be given a repeat count;
this includes text characters.  Repeating a text character inserts
it several times.

>>  Try that now -- type C-u 8 * to insert ********.

You've now learned the most basic way of typing something in
Emacs and correcting errors.  You can delete by words or lines
as well.  Here is a summary of the delete operations:

	<Delete>     delete the character just before the cursor
	C-d   	     delete the next character after the cursor

	M-<Delete>   kill the word immediately before the cursor
	M-d	     kill the next word after the cursor

	C-k	     kill from the cursor position to end of line
	M-k	     kill to the end of the current sentence

Notice that <Delete> and C-d vs M-<Delete> and M-d extend the parallel
started by C-f and M-f (well, <Delete> is not really a control
character, but let's not worry about that).  C-k and M-k are like C-e
and M-e, sort of, in that lines are opposite sentences.

When you delete more than one character at a time, Emacs saves the
deleted text so that you can bring it back.  Bringing back killed text
is called "yanking".  You can yank the killed text either at the same
place where it was killed, or at some other place in the text.  You
can yank the text several times in order to make multiple copies of
it.  The command to yank is C-y.

Note that the difference between "Killing" and "Deleting" something is
that "Killed" things can be yanked back, and "Deleted" things cannot.
Generally, the commands that can remove a lot of text save the text,
while the commands that delete just one character, or just blank lines
and spaces, do not save the deleted text.

>> Move the cursor to the  beginning of a line which is not empty.
   Then type C-k to kill the text on that line.
>> Type C-k a second time.  You'll see that it kills the Newline
   which follows that line.

Note that a single C-k kills the contents of the line, and a second
C-k kills the line itself, and make all the other lines move up.  C-k
treats a numeric argument specially: it kills that many lines AND
their contents.  This is not mere repetition.  C-u 2 C-k kills two
lines and their newlines; typing C-k twice would not do that.

To retrieve the last killed text and put it where the cursor currently
is, type C-y.

>> Try it; type C-y to yank the text back.

Think of C-y as if you were yanking something back that someone took
away from you.  Notice that if you do several C-k's in a row, all of
the killed text is saved together, so that one C-y will yank all of
the lines.

>> Do this now, type C-k several times.

Now to retrieve that killed text:

>> Type C-y.  Then move the cursor down a few lines and type C-y
   again.  You now see how to copy some text.

What do you do if you have some text you want to yank back, and then
you kill something else?  C-y would yank the more recent kill.  But
the previous text is not lost.  You can get back to it using the M-y
command.  After you have done C-y to get the most recent kill, typing
M-y replaces that yanked text with the previous kill.  Typing M-y
again and again brings in earlier and earlier kills.  When you have
reached the text you are looking for, you do not have to do anything to
keep it.  Just go on with your editing, leaving the yanked text where
it is.

If you M-y enough times, you come back to the starting point (the most
recent kill).

>> Kill a line, move around, kill another line.
   Then do C-y to get back the second killed line.
   Then do M-y and it will be replaced by the first killed line.
   Do more M-y's and see what you get.  Keep doing them until
   the second kill line comes back, and then a few more.
   If you like, you can try giving M-y positive and negative
   arguments.


* UNDO
------

If you make a change to the text, and then decide that it was a
mistake, you can undo the change with the undo command, C-x u.

Normally, C-x u undoes the changes made by one command; if you repeat
the C-x u several times in a row, each repetition undoes one
additional command.

But there are two exceptions: commands that do not change the text do
not count (this includes cursor motion commands and scrolling
command), and self-inserting characters are usually handled in groups
of up to 20.  (This is to reduce the number of C-x u's you have to
type to undo insertion of text.)

>> Kill this line with C-k, then type C-x u and it should reappear.

C-_ is an alternative undo command; it works just the same as C-x u,
but it is easier to type several times in a row.  The disadvantage of
C-_ is that on some keyboards it is not obvious how to type it.  That
is why we provide C-x u as well.  On some terminals, you can type C-_
by typing / while holding down CONTROL.

A numeric argument to C-_ or C-x u acts as a repeat count.


* FILES
-------

In order to make the text you edit permanent, you must put it in a
file.  Otherwise, it will go away when your invocation of Emacs goes
away.  In order to put your text in a file, you must "find" the file
before you enter the text.  (This is also called "visiting" the file.)

Finding a file means that you see the contents of the file within
Emacs.  In many ways, it is as if you were editing the file itself.
However, the changes you make using Emacs do not become permanent
until you "save" the file.  This is so you can avoid leaving a
half-changed file on the system when you do not want to.  Even when
you save, Emacs leaves the original file under a changed name in case
you later decide that your changes were a mistake.

If you look near the bottom of the screen you will see a line that
begins and ends with dashes, and starts with "--:-- TUTORIAL" or
something like that.  This part of the screen normally shows the name
of the file that you are visiting.  Right now, you are visiting a file
called "TUTORIAL" which is your personal scratch copy of the Emacs
tutorial.  When you find a file with Emacs, that file's name will
appear in that precise spot.

One special thing about the command for finding a file is that you
have to say what file name you want.  We say the command "reads an
argument from the terminal" (in this case, the argument is the name of
the file).  After you type the command

	C-x C-f   Find a file

Emacs asks you to type the file name.  The file name you type appears
on the bottom line of the screen.  The bottom line is called the
minibuffer when it is used for this sort of input.  You can use
ordinary Emacs editing commands to edit the file name.

While you are entering the file name (or any minibuffer input),
you can cancel the command with C-g.

>> Type C-x C-f, then type C-g.  This cancels the minibuffer,
   and also cancels the C-x C-f command that was using the
   minibuffer.  So you do not find any file.

When you have finished entering the file name, type <Return> to
terminate it.  Then C-x C-f command goes to work, and finds the file
you chose.  The minibuffer disappears when the C-x C-f command is
finished.

In a little while the file contents appear on the screen, and you can
edit the contents.  When you wish to make your changes permanent,
type the command

	C-x C-s   Save the file

This copies the text within Emacs into the file.  The first time you
do this, Emacs renames the original file to a new name so that it is
not lost.  The new name is made by adding "~" to the end of the
original file's name.

When saving is finished, Emacs prints the name of the file written.
You should save fairly often, so that you will not lose very much
work if the system should crash.

>> Type C-x C-s, saving your copy of the tutorial.
   This should print "Wrote ...TUTORIAL" at the bottom of the screen.

NOTE: On some systems, typing C-x C-s will freeze the screen and you
will see no further output from Emacs.  This indicates that an
operating system "feature" called "flow control" is intercepting the
C-s and not letting it get through to Emacs.  To unfreeze the screen,
type C-q.  Then see the section "Spontaneous Entry to Incremental
Search" in the Emacs manual for advice on dealing with this "feature".

You can find an existing file, to view it or edit it.  You can also
find a file which does not already exist.  This is the way to create a
file with Emacs: find the file, which will start out empty, and then
begin inserting the text for the file.  When you ask to "save" the
file, Emacs will really create the file with the text that you have
inserted.  From then on, you can consider yourself to be editing an
already existing file.


* BUFFERS
---------

If you find a second file with C-x C-f, the first file remains
inside Emacs.  You can switch back to it by finding it again with
C-x C-f.  This way you can get quite a number of files inside Emacs.

>> Create a file named "foo" by typing  C-x C-f foo <Return>.
   Then insert some text, edit it, and save "foo" by typing  C-x C-s.
   Finally, type C-x C-f TUTORIAL <Return>
   to come back to the tutorial.

Emacs stores each file's text inside an object called a "buffer".
Finding a file makes a new buffer inside Emacs.  To see a list of the
buffers that currently exist in your Emacs job, type

	C-x C-b   List buffers

>> Try C-x C-b now.

See how each buffer has a name, and it may also have a file name
for the file whose contents it holds.  Some buffers do not correspond
to files.  For example, the buffer named "*Buffer List*" does
not have any file.  It is the buffer which contains the buffer
list that was made by C-x C-b.  ANY text you see in an Emacs window
is always part of some buffer.

>> Type C-x 1 to get rid of the buffer list.

If you make changes to the text of one file, then find another file,
this does not save the first file.  Its changes remain inside Emacs,
in that file's buffer.  The creation or editing of the second file's
buffer has no effect on the first file's buffer.  This is very useful,
but it also means that you need a convenient way to save the first
file's buffer.  It would be a nuisance to have to switch back to
it with C-x C-f in order to save it with C-x C-s.  So we have

	C-x s     Save some buffers

C-x s asks you about each buffer which contains changes that you have
not saved.  It asks you, for each such buffer, whether to save the
buffer.

>> Insert a line of text, then type C-x s.
   It should ask you whether to save the buffer named TUTORIAL.
   Answer yes to the question by typing "y".

* EXTENDING THE COMMAND SET
---------------------------

There are many, many more Emacs commands than could possibly be put
on all the control and meta characters.  Emacs gets around this with
the X (eXtend) command.  This comes in two flavors:

	C-x	Character eXtend.  Followed by one character.
	M-x	Named command eXtend.  Followed by a long name.

These are commands that are generally useful but used less than the
commands you have already learned about.  You have already seen two of
them: the file commands C-x C-f to Find and C-x C-s to Save.  Another
example is the command to end the Emacs session--this is the command
C-x C-c.  (Do not worry about losing changes you have made; C-x C-c
offers to save each changed file before it kills the Emacs.)

C-z is the command to exit Emacs *temporarily*--so that you can go
back to the same Emacs session afterward.

On systems which allow it, C-z "suspends" Emacs; that is, it returns
to the shell but does not destroy the Emacs.  In the most common
shells, you can resume Emacs with the `fg' command or with `%emacs'.

On systems which do not implement suspending, C-z creates a subshell
running under Emacs to give you the chance to run other programs and
return to Emacs afterward; it does not truly "exit" from Emacs.  In
this case, the shell command `exit' is the usual way to get back to
Emacs from the subshell.

The time to use C-x C-c is when you are about to log out.  It's also
the right thing to use to exit an Emacs invoked under mail handling
programs and other miscellaneous utilities, since they may not know
how to cope with suspension of Emacs.  In ordinary circumstances,
though, if you are not about to log out, it is better to suspend Emacs
with C-z instead of exiting Emacs.

There are many C-x commands.  Here is a list of the ones you have learned:

	C-x C-f		Find file.
	C-x C-s		Save file.
	C-x C-b		List buffers.
	C-x C-c		Quit Emacs.
	C-x u		Undo.

Named eXtended commands are commands which are used even less
frequently, or commands which are used only in certain modes.  An
example is the command replace-string, which globally replaces one
string with another.  When you type M-x, Emacs prompts you at the
bottom of the screen with M-x and you should type the name of the
command; in this case, "replace-string".  Just type "repl s<TAB>" and
Emacs will complete the name.  End the command name with <Return>.

The replace-string command requires two arguments--the string to be
replaced, and the string to replace it with.  You must end each
argument with <Return>.

>> Move the cursor to the blank line two lines below this one.
   Then type M-x repl s<Return>changed<Return>altered<Return>.

   Notice how this line has changed: you've replaced
   the word c-h-a-n-g-e-d with "altered" wherever it occurred,
   after the initial position of the cursor.


* AUTO SAVE
-----------

When you have made changes in a file, but you have not saved them yet,
they could be lost if your computer crashes.  To protect you from
this, Emacs periodically writes an "auto save" file for each file that
you are editing.  The auto save file name has a # at the beginning and
the end; for example, if your file is named "hello.c", its auto save
file's name is "#hello.c#".  When you save the file in the normal way,
Emacs deletes its auto save file.

If the computer crashes, you can recover your auto-saved editing by
finding the file normally (the file you were editing, not the auto
save file) and then typing M-x recover file<Return>.  When it asks for
confirmation, type yes<Return> to go ahead and recover the auto-save
data.


* ECHO AREA
-----------

If Emacs sees that you are typing commands slowly it shows them to you
at the bottom of the screen in an area called the "echo area".  The echo
area contains the bottom line of the screen.


* MODE LINE
-----------

The line immediately above the echo area it is called the "mode line".
The mode line says something like this:

--:**  TUTORIAL          (Fundamental)--L670--58%----------------

This line gives useful information about the status of Emacs and
the text you are editing.

You already know what the filename means--it is the file you have
found.  -NN%-- indicates your current position in the text; it means
that NN percent of the text is above the top of the screen.  If the
top of the file is on the screen, it will say --Top-- instead of
--00%--.  If the bottom of the text is on the screen, it will say
--Bot--.  If you are looking at text so small that all of it fits on
the screen, the mode line says --All--.

The stars near the front mean that you have made changes to the text.
Right after you visit or save a file, that part of the mode line shows
no stars, just dashes.

The part of the mode line inside the parentheses is to tell you what
editing modes you are in.  The default mode is Fundamental which is
what you are using now.  It is an example of a "major mode".  

Emacs has many different major modes.  Some of them are meant for
editing different languages and/or kinds of text, such as Lisp mode,
Text mode, etc.  At any time one and only one major mode is active,
and its name can always be found in the mode line just where
"Fundamental" is now.

Each major mode makes a few commands behave differently.  For example,
there are commands for creating comments in a program, and since each
programming language has a different idea of what a comment should
look like, each major mode has to insert comments differently.  Each
major mode is the name of an extended command, which is how you can
switch to that mode.  For example, M-x fundamental-mode is a command to
switch to Fundamental mode.

If you are going to be editing English text, such as this file, you
should probably use Text Mode.
>> Type M-x text mode<Return>.

Don't worry, none of the commands you have learned changes Emacs in
any great way.  But you can observe that M-f and M-b now treat
apostrophes as part of words.  Previously, in Fundamental mode,
M-f and M-b treated apostrophes as word-separators.

Major modes usually make subtle changes like that one: most commands
do "the same job" in each major mode, but they work a little bit
differently.

To view documentation on your current major mode, type C-h m.

>> Use C-u C-v once or more to bring this line near the top of screen.
>> Type C-h m, to see how Text mode differs from Fundamental mode.
>> Type C-x 1 to remove the documentation from the screen.

Major modes are called major because there are also minor modes.
Minor modes are alternatives not to the major modes, just minor
modifications of them.  Each minor mode can be turned on or off by
itself, independent of all other minor modes, and independent of your
major mode.  So you can use no minor modes, or one minor mode, or any
combination of several minor modes.

One minor mode which is very useful, especially for editing English
text, is Auto Fill mode.  When this mode is on, Emacs breaks the line
in between words automatically whenever you insert text and make a
line that is too wide.

You can turn Auto Fill mode on by doing M-x auto fill mode<Return>.
When the mode is on, you can turn it off by doing M-x
auto fill mode<Return>.  If the mode is off, this command turns it on,
and if the mode is on, this command turns it off.  We say that the
command "toggles the mode".

>> Type M-x auto fill mode<Return> now.  Then insert a line of "asdf "
   over again until you see it divide into two lines.  You must put in
   spaces between them because Auto Fill breaks lines only at spaces.

The margin is usually set at 70 characters, but you can change it
with the C-x f command.  You should give the margin setting you want
as a numeric argument.

>> Type C-x f with an argument of 20.  (C-u 2 0 C-x f).
   Then type in some text and see Emacs fill lines of 20
   characters with it.  Then set the margin back to 70 using
   C-x f again.

If you makes changes in the middle of a paragraph, Auto Fill mode
does not re-fill it for you.
To re-fill the paragraph, type M-q (Meta-q) with the cursor inside
that paragraph.

>> Move the cursor into the previous paragraph and type M-q.

* SEARCHING
-----------

Emacs can do searches for strings (these are groups of contiguous
characters or words) either forward through the text or backward
through it.  Searching for a string is a cursor motion command;
it moves the cursor to the next place where that string appears.

The Emacs search command is different from the search commands
of most editors, in that it is "incremental".  This means that the
search happens while you type in the string to search for.

The command to initiate a search is C-s for forward search, and C-r
for reverse search.  BUT WAIT!  Don't try them now.

When you type C-s you'll notice that the string "I-search" appears as
a prompt in the echo area.  This tells you that Emacs is in what is
called an incremental search waiting for you to type the thing that
you want to search for.  <Return> terminates a search.

>> Now type C-s to start a search.  SLOWLY, one letter at a time,
   type the word 'cursor', pausing after you type each
   character to notice what happens to the cursor.
   Now you have searched for "cursor", once.
>> Type C-s again, to search for the next occurrence of "cursor".
>> Now type <Delete> four times and see how the cursor moves.
>> Type <Return> to terminate the search.

Did you see what happened?  Emacs, in an incremental search, tries to
go to the occurrence of the string that you've typed out so far.  To
go to the next occurrence of 'cursor' just type C-s again.  If no such
occurrence exists Emacs beeps and tells you the search is currently
"failing", C-g would also terminate the search.

NOTE: On some systems, typing C-s will freeze the screen and you will
see no further output from Emacs.  This indicates that an operating
system "feature" called "flow control" is intercepting the C-s and not
letting it get through to Emacs.  To unfreeze the screen, type C-q.
Then see the section "Spontaneous Entry to Incremental Search" in the
Emacs manual for advice on dealing with this "feature".

If you are in the middle of an incremental search and type <Delete>,
you'll notice that the last character in the search string is erased
and the search backs up to the last place of the search.  For
instance, suppose you have typed "c", to search for the first
occurrence of "c".  Now if you type "u", the cursor will move
to the first occurrence of "cu".  Now type <Delete>.  This erases
the "u" from the search string, and the cursor moves back to
the first occurrence of "c".

If you are in the middle of a search and type a control or meta
character (with a few exceptions--characters that are special in
a search, such as C-s and C-r), the search is terminated.

The C-s starts a search that looks for any occurrence of the search
string AFTER the current cursor position.  If you want to search for
something earlier in the text, type C-r instead.  Everything that we
have said about C-s also applies to C-r, except that the direction of
the search is reversed.


* MULTIPLE WINDOWS
------------------

One of the nice features of Emacs is that you can display more than one
window on the screen at the same time.

>> Move the cursor to this line and type C-u 0 C-l.

>> Now type C-x 2 which splits the screen into two windows.
   Both windows display this tutorial.  The cursor stays in the top window.

>> Type C-M-v to scroll the bottom window.
   (If you do not have a real Meta key, type ESC C-v.)

>> Type C-x o ("o" for "other") to move the cursor to the bottom window.
>> Use C-v and M-v in the bottom window to scroll it.
   Keep reading these directions in the top window.

>> Type C-x o again to move the cursor back to the top window.
   The cursor in the top window is just where it was before.

You can keep using C-x o to switch between the windows.  Each
window has its own cursor position, but only one window actually
shows the cursor.  All the ordinary editing commands apply to the
window that the cursor is in.  We call this the "selected window".

The command C-M-v is very useful when you are editing text in one
window and using the other window just for reference.  You can keep
the cursor always in the window where you are editing, and advance
through the other window sequentially with C-M-v.

C-M-v is an example of a CONTROL-META character.  If you have a real
META key, you can type C-M-v by holding down both CONTROL and META while
typing v.  It does not matter whether CONTROL or META "comes first,"
because both of these keys act by modifying the characters you type.

If you do not have a real META key, and you use ESC instead, the order
does matter: you must type ESC followed by Control-v, because
Control-ESC v will not work.  This is because ESC is a character in
its own right, not a modifier key.

>> Type C-x 1 (in the top window) to get rid of the bottom window.

(If you had typed C-x 1 in the bottom window, that would get rid
of the top one.  Think of this command as "Keep just one
window--the window I am already in.")

You do not have to display the same buffer in both windows.  If you
use C-x C-f to find a file in one window, the other window does not
change.  You can find a file in each window independently.

Here is another way to use two windows to display two different
things:

>> Type C-x 4 C-f followed by the name of one of your files.
   End with <Return>.  See the specified file appear in the bottom
   window.  The cursor goes there, too.

>> Type C-x o to go back to the top window, and C-x 1 to delete
   the bottom window.


* RECURSIVE EDITING LEVELS
--------------------------

Sometimes you will get into what is called a "recursive editing
level".  This is indicated by square brackets in the mode line,
surrounding the parentheses around the major mode name.  For
example, you might see [(Fundamental)] instead of (Fundamental).

To get out of the recursive editing level, type ESC ESC ESC.  That is
an all-purpose "get out" command.  You can also use it for eliminating
extra windows, and getting out of the minibuffer.

>> Type M-x to get into a minibuffer; then type ESC ESC ESC to get out.

You cannot use C-g to get out of a recursive editing level.  This is
because C-g is used for canceling commands and arguments WITHIN the
recursive editing level.


* GETTING MORE HELP
-------------------

In this tutorial we have tried to supply just enough information to
get you started using Emacs.  There is so much available in Emacs that
it would be impossible to explain it all here.  However, you may want
to learn more about Emacs since it has many other useful features.
Emacs provides commands for reading documentation about Emacs
commands.  These "help" commands all start with the character
Control-h, which is called "the Help character".

To use the Help features, type the C-h character, and then a
character saying what kind of help you want.  If you are REALLY lost,
type C-h ? and Emacs will tell you what kinds of help it can give.
If you have typed C-h and decide you do not want any help, just
type C-g to cancel it.

(Some sites change the meaning of the character C-h.  They really
should not do this as a blanket measure for all users, so you have
grounds to complain to the system administrator.  Meanwhile, if C-h
does not display a message about help at the bottom of the screen, try
typing the F1 key or M-x help <Return> instead.)

The most basic HELP feature is C-h c.  Type C-h, the character c, and
a command character or sequence; then Emacs displays a very brief
description of the command.

>> Type C-h c Control-p.
  The message should be something like

	C-p runs the command previous-line

This tells you the "name of the function".  Function names are used
mainly for customizing and extending Emacs.  But since function names
are chosen to indicate what the command does, they can serve also as
very brief documentation--sufficient to remind you of commands you
have already learned.

Multi-character commands such as C-x C-s and (if you have no META or
EDIT or ALT key) <ESC>v are also allowed after C-h c.

To get more information about a command, use C-h k instead of C-h c.

>> Type C-h k Control-p.

This displays the documentation of the function, as well as its
name, in an Emacs window.  When you are finished reading the
output, type C-x 1 to get rid of the help text.  You do not have
to do this right away.  You can do some editing while referring
to the help text, and then type C-x 1.

Here are some other useful C-h options:

   C-h f	Describe a function.  You type in the name of the
		function.

>> Try typing C-h f previous-line<Return>.
   This prints all the information Emacs has about the
   function which implements the C-p command.

   C-h a	Command Apropos.  Type in a keyword and Emacs will list
		all the commands whose names contain that keyword.
		These commands can all be invoked with Meta-x.
		For some commands, Command Apropos will also list a one
		or two character sequence which runs the same command.

>> Type C-h a file<Return>.

This displays in another window a list of all M-x commands with "file"
in their names.  You will see character-commands like C-x C-f listed
beside the corresponding command names such as find-file.

>> Type C-M-v to scroll the help window.  Do this a few times.

>> Type C-x 1 to delete the help window.


* CONCLUSION
------------

Remember, to exit Emacs permanently use C-x C-c.  To exit to a shell
temporarily, so that you can come back to Emacs afterward, use C-z.

This tutorial is meant to be understandable to all new users, so if
you found something unclear, don't sit and blame yourself - complain!


COPYING
-------

This tutorial descends from a long line of Emacs tutorials
starting with the one written by Stuart Cracraft for the original Emacs.

This version of the tutorial, like GNU Emacs, is copyrighted, and
comes with permission to distribute copies on certain conditions:

Copyright (c) 1985, 1996 Free Software Foundation

   Permission is granted to anyone to make or distribute verbatim copies
   of this document as received, in any medium, provided that the
   copyright notice and permission notice are preserved,
   and that the distributor grants the recipient permission
   for further redistribution as permitted by this notice.

   Permission is granted to distribute modified versions
   of this document, or of portions of it,
   under the above conditions, provided also that they
   carry prominent notices stating who last altered them.

The conditions for copying Emacs itself are more complex, but in the
same spirit.  Please read the file COPYING and then do give copies of
GNU Emacs to your friends.  Help stamp out software obstructionism
("ownership") by using, writing, and sharing free software!
Tip: Filter by directory path e.g. /media app.js to search for public/media/app.js.
Tip: Use camelCasing e.g. ProjME to search for ProjectModifiedEvent.java.
Tip: Filter by extension type e.g. /repo .js to search for all .js files in the /repo directory.
Tip: Separate your search with spaces e.g. /ssh pom.xml to search for src/ssh/pom.xml.
Tip: Use ↑ and ↓ arrow keys to navigate and return to view the file.
Tip: You can also navigate files with Ctrl+j (next) and Ctrl+k (previous) and view the file with Ctrl+o.
Tip: You can also navigate files with Alt+j (next) and Alt+k (previous) and view the file with Alt+o.