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    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 To quit a partially entered command, type C-g.
   15 To stop the tutorial, type C-x k, then <Return> at the prompt.
   16 The characters ">>" at the left margin indicate directions for you to
   17 try using a command.  For instance:
   18 <<Blank lines inserted around following line by help-with-tutorial>>
   19 [Middle of page left blank for didactic purposes.   Text continues below]
   20 >> Now type C-v (View next screen) to scroll down in the tutorial.
   21 	(go ahead, do it by holding down the CONTROL key while typing v).
   22 	From now on, please do this whenever you reach the end of the screen.
   23 
   24 Note that there is an overlap of two lines when you scroll a whole
   25 screenful; this provides some continuity so you can continue reading
   26 the text.
   27 
   28 This is a copy of the Emacs tutorial text, customized slightly for
   29 you.  Later on we will instruct you to try various commands to alter
   30 this text.  Don't worry if you change this text before we tell you to;
   31 that is called "editing" and that's what Emacs is for.
   32 
   33 The first thing that you need to know is how to move around from place
   34 to place in the text.  You already know how to move forward one screen,
   35 with C-v.  To move backwards one screen, type M-v (hold down the META key
   36 and type v, or type <ESC>v if you do not have a META, EDIT, or ALT key).
   37 
   38 >> Try typing M-v and then C-v, a few times.
   39 
   40 It is ok to scroll this text in other ways, if you know how.
   41 
   42 * SUMMARY
   43 ---------
   44 
   45 The following commands are useful for viewing screenfuls:
   46 
   47 	C-v	Move forward one screenful
   48 	M-v	Move backward one screenful
   49 	C-l	Clear screen and redisplay all the text,
   50 		 moving the text around the cursor
   51 		 to the center of the screen.
   52 		 (That's CONTROL-L, not CONTROL-1.)
   53 
   54 >> Find the cursor, and note what text is near it.  Then type C-l.
   55    Find the cursor again and notice that the same text is still near
   56    the cursor, but now it is in the center of the screen.
   57    If you press C-l again, this piece of text will move to the top of
   58    the screen.  Press C-l again, and it moves to the bottom.
   59 
   60 You can also use the PageUp and PageDn keys to move by screenfuls, if
   61 your terminal has them, but you can edit more efficiently if you use
   62 C-v and M-v.
   63 
   64 * BASIC CURSOR CONTROL
   65 ----------------------
   66 
   67 Moving from screenful to screenful is useful, but how do you
   68 move to a specific place within the text on the screen?
   69 
   70 There are several ways you can do this.  You can use the arrow keys,
   71 but it's more efficient to keep your hands in the standard position
   72 and use the commands C-p, C-b, C-f, and C-n.  These characters
   73 are equivalent to the four arrow keys, like this:
   74 
   75 			  Previous line, C-p
   76 				  :
   77 				  :
   78    Backward, C-b .... Current cursor position .... Forward, C-f
   79 				  :
   80 				  :
   81 			    Next line, C-n
   82 
   83 >> Move the cursor to the line in the middle of that diagram
   84    using C-n or C-p.  Then type C-l to see the whole diagram
   85    centered in the screen.
   86 
   87 You'll find it easy to remember these letters by words they stand for:
   88 P for previous, N for next, B for backward and F for forward.  You
   89 will be using these basic cursor positioning commands all the time.
   90 
   91 >> Do a few C-n's to bring the cursor down to this line.
   92 
   93 >> Move into the line with C-f's and then up with C-p's.
   94    See what C-p does when the cursor is in the middle of the line.
   95 
   96 Each line of text ends with a Newline character, which serves to
   97 separate it from the following line.  (Normally, the last line in
   98 a file will have a Newline at the end, but Emacs does not require it.)
   99 
  100 >> Try to C-b at the beginning of a line.  It should move to
  101    the end of the previous line.  This is because it moves back
  102    across the Newline character.
  103 
  104 C-f can move across a Newline just like C-b.
  105 
  106 >> Do a few more C-b's, so you get a feel for where the cursor is.
  107    Then do C-f's to return to the end of the line.
  108    Then do one more C-f to move to the following line.
  109 
  110 When you move past the top or bottom of the screen, the text beyond
  111 the edge shifts onto the screen.  This is called "scrolling".  It
  112 enables Emacs to move the cursor to the specified place in the text
  113 without moving it off the screen.
  114 
  115 >> Try to move the cursor off the bottom of the screen with C-n, and
  116    see what happens.
  117 
  118 If moving by characters is too slow, you can move by words.  M-f
  119 (META-f) moves forward a word and M-b moves back a word.
  120 
  121 >> Type a few M-f's and M-b's.
  122 
  123 When you are in the middle of a word, M-f moves to the end of the word.
  124 When you are in whitespace between words, M-f moves to the end of the
  125 following word.  M-b works likewise in the opposite direction.
  126 
  127 >> Type M-f and M-b a few times, interspersed with C-f's and C-b's
  128    so that you can observe the action of M-f and M-b from various
  129    places inside and between words.
  130 
  131 Notice the parallel between C-f and C-b on the one hand, and M-f and
  132 M-b on the other hand.  Very often Meta characters are used for
  133 operations related to the units defined by language (words, sentences,
  134 paragraphs), while Control characters operate on basic units that are
  135 independent of what you are editing (characters, lines, etc).
  136 
  137 This parallel applies between lines and sentences: C-a and C-e move to
  138 the beginning or end of a line, and M-a and M-e move to the beginning
  139 or end of a sentence.
  140 
  141 >> Try a couple of C-a's, and then a couple of C-e's.
  142    Try a couple of M-a's, and then a couple of M-e's.
  143 
  144 See how repeated C-a's do nothing, but repeated M-a's keep moving one
  145 more sentence.  Although these are not quite analogous, each one seems
  146 natural.
  147 
  148 The location of the cursor in the text is also called "point".  To
  149 paraphrase, the cursor shows on the screen where point is located in
  150 the text.
  151 
  152 Here is a summary of simple cursor-moving operations, including the
  153 word and sentence moving commands:
  154 
  155 	C-f	Move forward a character
  156 	C-b	Move backward a character
  157 
  158 	M-f	Move forward a word
  159 	M-b	Move backward a word
  160 
  161 	C-n	Move to next line
  162 	C-p	Move to previous line
  163 
  164 	C-a	Move to beginning of line
  165 	C-e	Move to end of line
  166 
  167 	M-a	Move back to beginning of sentence
  168 	M-e	Move forward to end of sentence
  169 
  170 >> Try all of these commands now a few times for practice.
  171    These are the most often used commands.
  172 
  173 Two other important cursor motion commands are M-< (META Less-than),
  174 which moves to the beginning of the whole text, and M-> (META
  175 Greater-than), which moves to the end of the whole text.
  176 
  177 On most terminals, the "<" is above the comma, so you must use the
  178 shift key to type it.  On these terminals you must use the shift key
  179 to type M-< also; without the shift key, you would be typing M-comma.
  180 
  181 >> Try M-< now, to move to the beginning of the tutorial.
  182    Then use C-v repeatedly to move back here.
  183 
  184 >> Try M-> now, to move to the end of the tutorial.
  185    Then use M-v repeatedly to move back here.
  186 
  187 You can also move the cursor with the arrow keys, if your terminal has
  188 arrow keys.  We recommend learning C-b, C-f, C-n and C-p for three
  189 reasons.  First, they work on all kinds of terminals.  Second, once
  190 you gain practice at using Emacs, you will find that typing these Control
  191 characters is faster than typing the arrow keys (because you do not
  192 have to move your hands away from touch-typing position).  Third, once
  193 you form the habit of using these Control character commands, you can
  194 easily learn to use other advanced cursor motion commands as well.
  195 
  196 Most Emacs commands accept a numeric argument; for most commands, this
  197 serves as a repeat-count.  The way you give a command a repeat count
  198 is by typing C-u and then the digits before you type the command.  If
  199 you have a META (or EDIT or ALT) key, there is another, alternative way
  200 to enter a numeric argument: type the digits while holding down the
  201 META key.  We recommend learning the C-u method because it works on
  202 any terminal.  The numeric argument is also called a "prefix argument",
  203 because you type the argument before the command it applies to.
  204 
  205 For instance, C-u 8 C-f moves forward eight characters.
  206 
  207 >> Try using C-n or C-p with a numeric argument, to move the cursor
  208    to a line near this one with just one command.
  209 
  210 Most commands use the numeric argument as a repeat count, but some
  211 commands use it in some other way.  Several commands (but none of
  212 those you have learned so far) use it as a flag--the presence of a
  213 prefix argument, regardless of its value, makes the command do
  214 something different.
  215 
  216 C-v and M-v are another kind of exception.  When given an argument,
  217 they scroll the text up or down by that many lines, rather than by a
  218 screenful.  For example, C-u 8 C-v scrolls by 8 lines.
  219 
  220 >> Try typing C-u 8 C-v now.
  221 
  222 This should have scrolled the text up by 8 lines.  If you would like
  223 to scroll it down again, you can give an argument to M-v.
  224 
  225 If you are using a graphical display, such as X or MS-Windows, there
  226 should be a tall rectangular area called a scroll bar on one side of
  227 the Emacs window.  You can scroll the text by clicking the mouse in
  228 the scroll bar.
  229 
  230 If your mouse has a wheel button, you can also use this to scroll.
  231 
  232 
  233 * IF EMACS STOPS RESPONDING
  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 argument of 100, then type C-g.
  244    Now type C-f.  It should move just one character, because you
  245    canceled the argument with C-g.
  246 
  247 If you have typed an <ESC> by mistake, you can get rid of it with a C-g.
  248 
  249 
  250 * DISABLED COMMANDS
  251 -------------------
  252 
  253 Some Emacs commands are "disabled" so that beginning users cannot use
  254 them by accident.
  255 
  256 If you type one of the disabled commands, Emacs displays a message
  257 saying what the command was, and asking you whether you want to go
  258 ahead and execute the command.
  259 
  260 If you really want to try the command, type <SPC> (the Space bar) in
  261 answer to the question.  Normally, if you do not want to execute the
  262 disabled command, answer the question with "n".
  263 
  264 >> Type C-x C-l (which is a disabled command),
  265    then type n to answer the question.
  266 
  267 
  268 * WINDOWS
  269 ---------
  270 
  271 Emacs can have several "windows", each displaying its own text.  We
  272 will explain later on how to use multiple windows.  Right now we want
  273 to explain how to get rid of extra windows and go back to basic
  274 one-window editing.  It is simple:
  275 
  276 	C-x 1	One window (i.e., kill all other windows).
  277 
  278 That is CONTROL-x followed by the digit 1.  C-x 1 expands the window
  279 which contains the cursor, to occupy the full screen.  It deletes all
  280 other windows.
  281 
  282 >> Move the cursor to this line and type C-u 0 C-l.
  283 >> Type C-h k C-f.
  284    See how this window shrinks, while a new one appears
  285    to display documentation on the C-f command.
  286 
  287 >> Type C-x 1 and see the documentation listing window disappear.
  288 
  289 There is a whole series of commands that start with CONTROL-x; many of
  290 them have to do with windows, files, buffers, and related things.
  291 These commands are two, three or four characters long.
  292 
  293 
  294 * INSERTING AND DELETING
  295 ------------------------
  296 
  297 If you want to insert text, just type the text.  Ordinary characters,
  298 like A, 7, *, etc., are inserted as you type them.  To insert a
  299 Newline character, type <Return> (this is the key on the keyboard
  300 which is sometimes labeled "Enter").
  301 
  302 To delete the character immediately before the current cursor
  303 position, type <DEL>.  This is the key on the keyboard usually labeled
  304 "Backspace"--the same one you normally use, outside Emacs, to delete
  305 the last character typed.
  306 
  307 There may also be another key on your keyboard labeled <Delete>, but
  308 that's not the one we refer to as <DEL>.
  309 
  310 >> Do this now--type a few characters, then delete them by
  311    typing <DEL> a few times.  Don't worry about this file
  312    being changed; you will not alter the master tutorial.
  313    This is your personal copy of it.
  314 
  315 When a line of text gets too big for one line on the screen, the line
  316 of text is "continued" onto a second screen line.  If you're using a
  317 graphical display, little curved arrows appear in the narrow spaces on
  318 each side of the text area (the left and right "fringes"), to indicate
  319 where a line has been continued.  If you're using a text terminal, the
  320 continued line is indicated by a backslash ('\') on the rightmost
  321 screen column.
  322 
  323 >> Insert text until you reach the right margin, and keep on inserting.
  324    You'll see a continuation line appear.
  325 
  326 >> Use <DEL>s to delete the text until the line fits on one screen
  327    line again.  The continuation line goes away.
  328 
  329 You can delete a Newline character just like any other character.
  330 Deleting the Newline character between two lines merges them into
  331 one line.  If the resulting combined line is too long to fit in the
  332 screen width, it will be displayed with a continuation line.
  333 
  334 >> Move the cursor to the beginning of a line and type <DEL>.  This
  335    merges that line with the previous line.
  336 
  337 >> Type <Return> to reinsert the Newline you deleted.
  338 
  339 The <Return> key is special, in that pressing it may do more than
  340 just insert a Newline character.  Depending on the surrounding text,
  341 it may insert whitespace after the Newline character, so that when
  342 you start typing on the newly created line, the text lines up with
  343 that on the previous line.  We call this behavior (where pressing a
  344 key does more than simply inserting the relevant character) "electric".
  345 
  346 >> Here is an example of <Return> being electric.
  347    Type <Return> at the end of this line.
  348 
  349 You should see that after inserting the Newline, Emacs inserts spaces
  350 so that the cursor moves under the "T" of "Type".
  351 
  352 Remember that most Emacs commands can be given a repeat count;
  353 this includes text characters.  Repeating a text character inserts
  354 it several times.
  355 
  356 >> Try that now -- type C-u 8 * to insert ********.
  357 
  358 You've now learned the most basic way of typing something in
  359 Emacs and correcting errors.  You can delete by words or lines
  360 as well.  Here is a summary of the delete operations:
  361 
  362 	<DEL>        Delete the character just before the cursor
  363 	C-d   	     Delete the next character after the cursor
  364 
  365 	M-<DEL>      Kill the word immediately before the cursor
  366 	M-d	     Kill the next word after the cursor
  367 
  368 	C-k	     Kill from the cursor position to end of line
  369 	M-k	     Kill to the end of the current sentence
  370 
  371 Notice that <DEL> and C-d vs M-<DEL> and M-d extend the parallel
  372 started by C-f and M-f (well, <DEL> is not really a control character,
  373 but let's not worry about that).  C-k and M-k are like C-e and M-e,
  374 sort of, in that lines are paired with sentences.
  375 
  376 You can also kill a segment of text with one uniform method.  Move to
  377 one end of that part, and type C-<SPC>.  (<SPC> is the Space bar.)
  378 Next, move the cursor to the other end of the text you intend to kill.
  379 As you do this, Emacs highlights the text between the cursor and the
  380 position where you typed C-<SPC>.  Finally, type C-w.  This kills all
  381 the text between the two positions.
  382 
  383 >> Move the cursor to the Y at the start of the previous paragraph.
  384 >> Type C-<SPC>.  Emacs should display a message "Mark set"
  385    at the bottom of the screen.
  386 >> Move the cursor to the n in "end", on the second line of the
  387    paragraph.
  388 >> Type C-w.  This will kill the text starting from the Y,
  389    and ending just before the n.
  390 
  391 The difference between "killing" and "deleting" is that "killed" text
  392 can be reinserted (at any position), whereas "deleted" things cannot
  393 be reinserted in this way (you can, however, undo a deletion--see
  394 below).  Reinsertion of killed text is called "yanking".  (Think of it
  395 as yanking back, or pulling back, some text that was taken away.)
  396 Generally, the commands that can remove a lot of text kill the text
  397 (they are set up so that you can yank the text), while the commands
  398 that remove just one character, or only remove blank lines and spaces,
  399 do deletion (so you cannot yank that text).  <DEL> and C-d do deletion
  400 in the simplest case, with no argument.  When given an argument, they
  401 kill instead.
  402 
  403 >> Move the cursor to the beginning of a line which is not empty.
  404    Then type C-k to kill the text on that line.
  405 >> Type C-k a second time.  You'll see that it kills the Newline
  406    which follows that line.
  407 
  408 Note that a single C-k kills the contents of the line, and a second
  409 C-k kills the line itself, and makes all the other lines move up.  C-k
  410 treats a numeric argument specially: it kills that many lines AND
  411 their contents.  This is not mere repetition.  C-u 2 C-k kills two
  412 lines and their Newlines; typing C-k twice would not do that.
  413 
  414 You can yank the killed text either at the same place where it was
  415 killed, or at some other place in the text you are editing, or even in
  416 a different file.  You can yank the same text several times; that
  417 makes multiple copies of it.  Some other editors call killing and
  418 yanking "cutting" and "pasting" (see the Glossary in the Emacs
  419 manual).
  420 
  421 The command for yanking is C-y.  It reinserts the last killed text,
  422 at the current cursor position.
  423 
  424 >> Try it; type C-y to yank the text back.
  425 
  426 If you do several C-k's in a row, all of the killed text is saved
  427 together, so that one C-y will yank all of the lines at once.
  428 
  429 >> Do this now, type C-k several times.
  430 
  431 Now to retrieve that killed text:
  432 
  433 >> Type C-y.  Then move the cursor down a few lines and type C-y
  434    again.  You now see how to copy some text.
  435 
  436 What do you do if you have some text you want to yank back, and then
  437 you kill something else?  C-y would yank the more recent kill.  But
  438 the previous text is not lost.  You can get back to it using the M-y
  439 command.  After you have done C-y to get the most recent kill, typing
  440 M-y replaces that yanked text with the previous kill.  Typing M-y
  441 again and again brings in earlier and earlier kills.  When you have
  442 reached the text you are looking for, you do not have to do anything to
  443 keep it.  Just go on with your editing, leaving the yanked text where
  444 it is.
  445 
  446 If you M-y enough times, you come back to the starting point (the most
  447 recent kill).
  448 
  449 >> Kill a line, move around, kill another line.
  450    Then do C-y to get back the second killed line.
  451    Then do M-y and it will be replaced by the first killed line.
  452    Do more M-y's and see what you get.  Keep doing them until
  453    the second kill line comes back, and then a few more.
  454    If you like, you can try giving M-y positive and negative
  455    arguments.
  456 
  457 
  458 * UNDO
  459 ------
  460 
  461 If you make a change to the text, and then decide that it was a
  462 mistake, you can undo the change with the undo command, C-/.
  463 
  464 Normally, C-/ undoes the changes made by one command; if you repeat
  465 C-/ several times in a row, each repetition undoes one more command.
  466 
  467 But there are two exceptions: commands that do not change the text
  468 don't count (this includes cursor motion commands and scrolling
  469 commands), and self-inserting characters are usually handled in groups
  470 of up to 20.  (This is to reduce the number of C-/'s you have to type
  471 to undo insertion of text.)
  472 
  473 >> Kill this line with C-k, then type C-/ and it should reappear.
  474 
  475 C-_ is an alternative undo command; it works exactly the same as C-/.
  476 On some text terminals, typing C-/ actually sends C-_ to Emacs.
  477 Alternatively, C-x u also works exactly like C-/, but is a little less
  478 convenient to type.
  479 
  480 A numeric argument to C-/, C-_, or C-x u acts as a repeat count.
  481 
  482 You can undo deletion of text just as you can undo killing of text.
  483 The distinction between killing something and deleting it affects
  484 whether you can yank it with C-y; it makes no difference for undo.
  485 
  486 
  487 * FILES
  488 -------
  489 
  490 In order to make the text you edit permanent, you must put it in a
  491 file.  Otherwise, it will go away when you exit Emacs.  In order to
  492 put your text in a file, you must "find" the file before you enter the
  493 text.  (This is also called "visiting" the file.)
  494 
  495 Finding a file means that you see the contents of the file within
  496 Emacs.  In many ways, it is as if you were editing the file itself.
  497 However, the changes you make using Emacs do not become permanent
  498 until you "save" the file.  This is so you can avoid leaving a
  499 half-changed file on the system when you do not want to.  Even when
  500 you save, Emacs leaves the original file under a changed name in case
  501 you later decide that your changes were a mistake.
  502 
  503 If you look near the bottom of the screen you will see a line that
  504 begins with dashes, and starts with " -:---  TUTORIAL" or something
  505 like that.  This part of the screen normally shows the name of the
  506 file that you are visiting.  Right now, you are visiting your personal
  507 copy of the Emacs tutorial, which is called "TUTORIAL".  When you find
  508 a file with Emacs, that file's name will appear in that precise spot.
  509 
  510 One special thing about the command for finding a file is that you
  511 have to say what file name you want.  We say the command "reads an
  512 argument" (in this case, the argument is the name of the file).  After
  513 you type the command
  514 
  515 	C-x C-f   Find a file
  516 
  517 Emacs asks you to type the file name.  The file name you type appears
  518 on the bottom line of the screen.  The bottom line is called the
  519 minibuffer when it is used for this sort of input.  You can use
  520 ordinary Emacs editing commands to edit the file name.
  521 
  522 While you are entering the file name (or any minibuffer input),
  523 you can cancel the command with C-g.
  524 
  525 >> Type C-x C-f, then type C-g.  This cancels the minibuffer,
  526    and also cancels the C-x C-f command that was using the
  527    minibuffer.  So you do not find any file.
  528 
  529 When you have finished entering the file name, type <Return> to
  530 terminate it.  The minibuffer disappears, and the C-x C-f command goes
  531 to work to find the file you chose.
  532 
  533 The file contents now appear on the screen, and you can edit the
  534 contents.  When you wish to make your changes permanent, type the
  535 command
  536 
  537 	C-x C-s   Save the file
  538 
  539 This copies the text within Emacs into the file.  The first time you
  540 do this, Emacs renames the original file to a new name so that it is
  541 not lost.  The new name is made by adding "~" to the end of the
  542 original file's name.  When saving is finished, Emacs displays the
  543 name of the file written.
  544 
  545 >> Type C-x C-s TUTORIAL <Return>.
  546    This should save this tutorial to a file named TUTORIAL, and show
  547    "Wrote ...TUTORIAL" at the bottom of the screen.
  548 
  549 You can find an existing file, to view it or edit it.  You can also
  550 find a file which does not already exist.  This is the way to create a
  551 file with Emacs: find the file, which starts out empty, and then begin
  552 inserting the text for the file.  When you ask to "save" the file,
  553 Emacs actually creates the file with the text that you have inserted.
  554 From then on, you can consider yourself to be editing an already
  555 existing file.
  556 
  557 
  558 * BUFFERS
  559 ---------
  560 
  561 If you find a second file with C-x C-f, the first file remains
  562 inside Emacs.  You can switch back to it by finding it again with
  563 C-x C-f.  This way you can get quite a number of files inside Emacs.
  564 
  565 Emacs stores each file's text inside an object called a "buffer".
  566 Finding a file makes a new buffer inside Emacs.  To see a list of the
  567 buffers that currently exist, type
  568 
  569 	C-x C-b   List buffers
  570 
  571 >> Try C-x C-b now.
  572 
  573 See how each buffer has a name, and it may also have a file name for
  574 the file whose contents it holds.  ANY text you see in an Emacs window
  575 is always part of some buffer.
  576 
  577 >> Type C-x 1 to get rid of the buffer list.
  578 
  579 When you have several buffers, only one of them is "current" at any
  580 time.  That buffer is the one you edit.  If you want to edit another
  581 buffer, you need to "switch" to it.  If you want to switch to a buffer
  582 that corresponds to a file, you can do it by visiting the file again
  583 with C-x C-f.  But there is an easier way: use the C-x b command.
  584 In that command, you have to type the buffer's name.
  585 
  586 >> Create a file named "foo" by typing C-x C-f foo <Return>.
  587    Then type C-x b TUTORIAL <Return> to come back to this tutorial.
  588 
  589 Most of the time, the buffer's name is the same as the file name
  590 (without the file directory part).  However, this is not always true.
  591 The buffer list you make with C-x C-b shows you both the buffer name
  592 and the file name of every buffer.
  593 
  594 Some buffers do not correspond to files.  The buffer named
  595 "*Buffer List*", which contains the buffer list that you made with
  596 C-x C-b, does not have any file.  This TUTORIAL buffer initially did
  597 not have a file, but now it does, because in the previous section you
  598 typed C-x C-s and saved it to a file.
  599 
  600 The buffer named "*Messages*" also does not correspond to any file.
  601 This buffer contains the messages that have appeared on the bottom
  602 line during your Emacs session.
  603 
  604 >> Type C-x b *Messages* <Return> to look at the buffer of messages.
  605    Then type C-x b TUTORIAL <Return> to come back to this tutorial.
  606 
  607 If you make changes to the text of one file, then find another file,
  608 this does not save the first file.  Its changes remain inside Emacs,
  609 in that file's buffer.  The creation or editing of the second file's
  610 buffer has no effect on the first file's buffer.  This is very useful,
  611 but it also means that you need a convenient way to save the first
  612 file's buffer.  Having to switch back to that buffer, in order to save
  613 it with C-x C-s, would be a nuisance.  So we have
  614 
  615 	C-x s     Save some buffers
  616 
  617 C-x s asks you about each buffer which contains changes that you have
  618 not saved.  It asks you, for each such buffer, whether to save the
  619 buffer.
  620 
  621 >> Insert a line of text, then type C-x s.
  622    It should ask you whether to save the buffer named TUTORIAL.
  623    Answer yes to the question by typing "y".
  624 
  625 
  626 * EXTENDING THE COMMAND SET
  627 ---------------------------
  628 
  629 There are many, many more Emacs commands than could possibly be put
  630 on all the control and meta characters.  Emacs gets around this with
  631 the X (eXtend) command.  This comes in two flavors:
  632 
  633 	C-x	Character eXtend.  Followed by one character.
  634 	M-x	Named command eXtend.  Followed by a long name.
  635 
  636 These are commands that are generally useful but are used less than the
  637 commands you have already learned about.  You have already seen a few
  638 of them: the file commands C-x C-f to Find and C-x C-s to Save, for
  639 example.  Another example is the command to end the Emacs
  640 session--this is the command C-x C-c.  (Do not worry about losing
  641 changes you have made; C-x C-c offers to save each changed file before
  642 it kills Emacs.)
  643 
  644 If you are using a graphical display, you don't need any special
  645 command to move from Emacs to another application.  You can do this
  646 with the mouse or with window manager commands.  However, if you're
  647 using a text terminal which can only show one application at a time,
  648 you need to "suspend" Emacs to move to any other application.
  649 
  650 C-z is the command to exit Emacs *temporarily*--so that you can go
  651 back to the same Emacs session afterward.  When Emacs is running on a
  652 text terminal, C-z "suspends" Emacs; that is, it returns to the shell
  653 but does not destroy the Emacs job.  In the most common shells, you
  654 can resume Emacs with the "fg" command or with "%emacs".
  655 
  656 The time to use C-x C-c is when you are about to log out.  It's also
  657 the right thing to use to exit an Emacs invoked for a quick edit, such
  658 as by a mail handling utility.
  659 
  660 There are many C-x commands.  Here is a list of the ones you have learned:
  661 
  662 	C-x C-f		Find file
  663 	C-x C-s		Save file
  664 	C-x s		Save some buffers
  665 	C-x C-b		List buffers
  666 	C-x b		Switch buffer
  667 	C-x C-c		Quit Emacs
  668 	C-x 1		Delete all but one window
  669 	C-x u		Undo
  670 
  671 Named eXtended commands are commands which are used even less
  672 frequently, or commands which are used only in certain modes.  An
  673 example is the command replace-string, which replaces one string with
  674 another in the buffer.  When you type M-x, Emacs prompts you at the
  675 bottom of the screen with M-x and you should type the name of the
  676 command; in this case, "replace-string".  Just type "repl s<TAB>" and
  677 Emacs will complete the name.  (<TAB> is the Tab key, usually found
  678 above the CapsLock or Shift key near the left edge of the keyboard.)
  679 Submit the command name with <Return>.
  680 
  681 The replace-string command requires two arguments--the string to be
  682 replaced, and the string to replace it with.  You must end each
  683 argument with <Return>.
  684 
  685 >> Move the cursor to the blank line two lines below this one.
  686    Then type M-x repl s<Return>changed<Return>altered<Return>.
  687 
  688    Notice how this line has changed: you've replaced the word
  689    "changed" with "altered" wherever it occurred, after the
  690    initial position of the cursor.
  691 
  692 
  693 * AUTO SAVE
  694 -----------
  695 
  696 When you have made changes in a file, but you have not saved them yet,
  697 they could be lost if your computer crashes.  To protect you from
  698 this, Emacs periodically writes an "auto save" file for each file that
  699 you are editing.  The auto save file name has a # at the beginning and
  700 the end; for example, if your file is named "hello.c", its auto save
  701 file's name is "#hello.c#".  When you save the file in the normal way,
  702 Emacs deletes its auto save file.
  703 
  704 If the computer crashes, you can recover your auto-saved editing by
  705 finding the file normally (the file you were editing, not the auto
  706 save file) and then typing M-x recover-this-file <Return>.  When it
  707 asks fo confirmation, type yes<Return> to go ahead and recover the
  708 auto-save data.
  709 
  710 
  711 * ECHO AREA
  712 -----------
  713 
  714 If Emacs sees that you are typing multicharacter commands slowly, it
  715 shows them to you at the bottom of the screen in an area called the
  716 "echo area".  The echo area contains the bottom line of the screen.
  717 
  718 
  719 * MODE LINE
  720 -----------
  721 
  722 The line immediately above the echo area is called the "mode line".
  723 The mode line says something like this:
  724 
  725  -:**-  TUTORIAL       63% L749    (Fundamental)
  726 
  727 This line gives useful information about the status of Emacs and
  728 the text you are editing.
  729 
  730 You already know what the filename means--it is the file you have
  731 found.  NN% indicates your current position in the buffer text; it
  732 means that NN percent of the buffer is above the top of the screen.
  733 If the top of the buffer is on the screen, it will say "Top" instead
  734 of " 0%".  If the bottom of the buffer is on the screen, it will say
  735 "Bot".  If you are looking at a buffer so small that all of it fits on
  736 the screen, the mode line says "All".
  737 
  738 The L and digits indicate position in another way: they give the
  739 current line number of point.
  740 
  741 The stars near the front mean that you have made changes to the text.
  742 Right after you visit or save a file, that part of the mode line shows
  743 no stars, just dashes.
  744 
  745 The part of the mode line inside the parentheses is to tell you what
  746 editing modes you are in.  The default mode is Fundamental which is
  747 what you are using now.  It is an example of a "major mode".
  748 
  749 Emacs has many different major modes.  Some of them are meant for
  750 editing different languages and/or kinds of text, such as Lisp mode,
  751 Text mode, etc.  At any time one and only one major mode is active,
  752 and its name can always be found in the mode line just where
  753 "Fundamental" is now.
  754 
  755 Each major mode makes a few commands behave differently.  For example,
  756 there are commands for creating comments in a program, and since each
  757 programming language has a different idea of what a comment should
  758 look like, each major mode has to insert comments differently.  Each
  759 major mode is the name of an extended command, which is how you can
  760 switch to that mode.  For example, M-x fundamental-mode is a command to
  761 switch to Fundamental mode.
  762 
  763 If you are going to be editing human-language text, such as this file, you
  764 should probably use Text Mode.
  765 
  766 >> Type M-x text-mode <Return>.
  767 
  768 Don't worry, none of the Emacs commands you have learned changes in
  769 any great way.  But you can observe that M-f and M-b now treat
  770 apostrophes as part of words.  Previously, in Fundamental mode,
  771 M-f and M-b treated apostrophes as word-separators.
  772 
  773 Major modes usually make subtle changes like that one: most commands
  774 do "the same job" in each major mode, but they work a little bit
  775 differently.
  776 
  777 To view documentation on your current major mode, type C-h m.
  778 
  779 >> Move the cursor to the line following this line.
  780 >> Type C-l C-l to bring this line to 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
  798 M-x auto-fill-mode <Return>.  If the mode is off, this command turns
  799 it on, and if the mode is on, this command turns it off.  We say that
  800 the 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 (a "string" is a group of contiguous
  827 characters) either forward through the text or backward through it.
  828 Searching for a string is a cursor motion command; it moves the cursor
  829 to the next place where that string appears.
  830 
  831 The Emacs search command is "incremental".  This means that the
  832 search happens while you type in the string to search for.
  833 
  834 The command to initiate a search is C-s for forward search, and C-r
  835 for reverse search.  BUT WAIT!  Don't try them now.
  836 
  837 When you type C-s you'll notice that the string "I-search" appears as
  838 a prompt in the echo area.  This tells you that Emacs is in what is
  839 called an incremental search waiting for you to type the thing that
  840 you want to search for.  <Return> terminates a search.
  841 
  842 >> Now type C-s to start a search.  SLOWLY, one letter at a time,
  843    type the word "cursor", pausing after you type each
  844    character to notice what happens to the cursor.
  845    Now you have searched for "cursor", once.
  846 >> Type C-s again, to search for the next occurrence of "cursor".
  847 >> Now type <DEL> four times and see how the cursor moves.
  848 >> Type <Return> to terminate the search.
  849 
  850 Did you see what happened?  Emacs, in an incremental search, tries to
  851 go to the occurrence of the string that you've typed out so far.  To
  852 go to the next occurrence of "cursor" just type C-s again.  If no such
  853 occurrence exists, Emacs beeps and tells you the search is currently
  854 "failing".  C-g would also terminate the search.
  855 
  856 If you are in the middle of an incremental search and type <DEL>, the
  857 search "retreats" to an earlier location.  If you type <DEL> just
  858 after you had typed C-s to advance to the next occurrence of a search
  859 string, the <DEL> moves the cursor back to an earlier occurrence.  If
  860 there are no earlier occurrences, the <DEL> erases the last character
  861 in the search string.  For instance, suppose you have typed "c", to
  862 search for the first occurrence of "c".  Now if you type "u", the
  863 cursor will move to the first occurrence of "cu".  Now type <DEL>.
  864 This erases the "u" from the search string, and the cursor moves back
  865 to the first occurrence of "c".
  866 
  867 If you are in the middle of a search and type a control or meta
  868 character (with a few exceptions--characters that are special in a
  869 search, such as C-s and C-r), the search is terminated.
  870 
  871 C-s starts a search that looks for any occurrence of the search string
  872 AFTER the current cursor position.  If you want to search for
  873 something earlier in the text, type C-r instead.  Everything that we
  874 have said about C-s also applies to C-r, except that the direction of
  875 the search is reversed.
  876 
  877 
  878 * MULTIPLE WINDOWS
  879 ------------------
  880 
  881 One of the nice features of Emacs is that you can display more than
  882 one window on the screen at the same time.  (Note that Emacs uses the
  883 term "frames"--described in the next section--for what some other
  884 applications call "windows".  The Emacs manual contains a Glossary of
  885 Emacs terms.)
  886 
  887 >> Move the cursor to this line and type C-l C-l.
  888 
  889 >> Now type C-x 2 which splits the screen into two windows.
  890    Both windows display this tutorial.  The editing cursor stays in
  891    the top window.
  892 
  893 >> Type C-M-v to scroll the bottom window.
  894    (If you do not have a real META key, type <ESC> C-v.)
  895 
  896 >> Type C-x o ("o" for "other") to move the cursor to the bottom window.
  897 >> Use C-v and M-v in the bottom window to scroll it.
  898    Keep reading these directions in the top window.
  899 
  900 >> Type C-x o again to move the cursor back to the top window.
  901    The cursor in the top window is just where it was before.
  902 
  903 You can keep using C-x o to switch between the windows.  The "selected
  904 window", where most editing takes place, is the one with a prominent
  905 cursor which blinks when you are not typing.  The other windows have
  906 their own cursor positions; if you are running Emacs in a graphical
  907 display, those cursors are drawn as unblinking hollow boxes.
  908 
  909 The command C-M-v is very useful when you are editing text in one
  910 window and using the other window just for reference.  Without leaving
  911 the selected window, you can scroll the text in the other window with
  912 C-M-v.
  913 
  914 C-M-v is an example of a CONTROL-META character.  If you have a META
  915 (or Alt) key, you can type C-M-v by holding down both CONTROL and META
  916 while typing v.  It does not matter whether CONTROL or META "comes
  917 first," as both of these keys act by modifying the characters you
  918 type.
  919 
  920 If you do not have a META key, and you use <ESC> instead, the order
  921 does matter: you must type <ESC> followed by CONTROL-v, because
  922 CONTROL-<ESC> v will not work.  This is because <ESC> is a character
  923 in its own right, not a modifier key.
  924 
  925 >> Type C-x 1 (in the top window) to get rid of the bottom window.
  926 
  927 (If you had typed C-x 1 in the bottom window, that would get rid
  928 of the top one.  Think of this command as "Keep just one
  929 window--the window I am already in.")
  930 
  931 You do not have to display the same buffer in both windows.  If you
  932 use C-x C-f to find a file in one window, the other window does not
  933 change.  You can find a file in each window independently.
  934 
  935 Here is another way to use two windows to display two different things:
  936 
  937 >> Type C-x 4 C-f followed by the name of one of your files.
  938    End with <Return>.  See the specified file appear in the bottom
  939    window.  The cursor goes there, too.
  940 
  941 >> Type C-x o to go back to the top window, and C-x 1 to delete
  942    the bottom window.
  943 
  944 
  945 * MULTIPLE FRAMES
  946 ------------------
  947 
  948 Emacs can also create multiple "frames".  A frame is what we call one
  949 collection of windows, together with its menus, scroll bars, echo
  950 area, etc.  On graphical displays, what Emacs calls a "frame" is what
  951 most other applications call a "window".  Multiple graphical frames
  952 can be shown on the screen at the same time.  On a text terminal, only
  953 one frame can be shown at a time.
  954 
  955 >> Type C-x 5 2.
  956    See a new frame appear on your screen.
  957 
  958 You can do everything you did in the original frame in the new frame.
  959 There is nothing special about the first frame.
  960 
  961 >> Type C-x 5 0.
  962    This removes the selected frame.
  963 
  964 You can also remove a frame by using the normal method provided by the
  965 graphical system (often clicking a button with an "X" at a top corner
  966 of the frame).  If you remove the Emacs job's last frame this way,
  967 that exits Emacs.
  968 
  969 
  970 * RECURSIVE EDITING LEVELS
  971 --------------------------
  972 
  973 Sometimes you will get into what is called a "recursive editing
  974 level".  This is indicated by square brackets in the mode line,
  975 surrounding the parentheses around the major mode name.  For
  976 example, you might see [(Fundamental)] instead of (Fundamental).
  977 
  978 To get out of the recursive editing level, type <ESC> <ESC> <ESC>.
  979 That is an all-purpose "get out" command.  You can also use it for
  980 eliminating extra windows, and getting out of the minibuffer.
  981 
  982 >> Type M-x to get into a minibuffer; then type <ESC> <ESC> <ESC> to
  983    get out.
  984 
  985 You cannot use C-g to get out of a recursive editing level.  This is
  986 because C-g is used for canceling commands and arguments WITHIN the
  987 recursive editing level.
  988 
  989 
  990 * GETTING MORE HELP
  991 -------------------
  992 
  993 In this tutorial we have tried to supply just enough information to
  994 get you started using Emacs.  There is so much available in Emacs that
  995 it would be impossible to explain it all here.  However, you may want
  996 to learn more about Emacs since it has many other useful features.
  997 Emacs provides commands for reading documentation about Emacs
  998 commands.  These "help" commands all start with the character
  999 CONTROL-h, which is called "the Help character".
 1000 
 1001 To use the Help features, type the C-h character, and then a
 1002 character saying what kind of help you want.  If you are REALLY lost,
 1003 type C-h ? and Emacs will tell you what kinds of help it can give.
 1004 If you have typed C-h and decide you do not want any help, just
 1005 type C-g to cancel it.
 1006 
 1007 (If C-h does not display a message about help at the bottom of the
 1008 screen, try typing the F1 key or M-x help <Return> instead.)
 1009 
 1010 The most basic HELP feature is C-h c.  Type C-h, the character c, and
 1011 a command character or sequence; then Emacs displays a very brief
 1012 description of the command.
 1013 
 1014 >> Type C-h c C-p.
 1015 
 1016 The message should be something like this:
 1017 
 1018 	C-p runs the command previous-line
 1019 
 1020 This tells you the "name of the function".  Since function names
 1021 are chosen to indicate what the command does, they can serve as
 1022 very brief documentation--sufficient to remind you of commands you
 1023 have already learned.
 1024 
 1025 Multi-character commands such as C-x C-s and <ESC>v (instead of M-v,
 1026 if you have no META or EDIT or ALT key) are also allowed after C-h c.
 1027 
 1028 To get more information about a command, use C-h k instead of C-h c.
 1029 
 1030 >> Type C-h k C-p.
 1031 
 1032 This displays the documentation of the function, as well as its name,
 1033 in an Emacs window.  When you are finished reading the output, type
 1034 C-x 1 to get rid of that window.  You do not have to do this right
 1035 away.  You can do some editing while referring to the help text, and
 1036 then type C-x 1.
 1037 
 1038 Here are some other useful C-h options:
 1039 
 1040    C-h f	Describe a function.  You type in the name of the
 1041 		function.
 1042 
 1043 >> Try typing C-h f previous-line <Return>.
 1044    This displays all the information Emacs has about the
 1045    function which implements the C-p command.
 1046 
 1047 A similar command C-h v displays the documentation of variables,
 1048 including those whose values you can set to customize Emacs behavior.
 1049 You need to type in the name of the variable when Emacs prompts for it.
 1050 
 1051    C-h a	Command Apropos.  Type in a keyword and Emacs will list
 1052 		all the commands whose names contain that keyword.
 1053 		These commands can all be invoked with META-x.
 1054 		For some commands, Command Apropos will also list a
 1055 		sequence of one or more characters which runs the same
 1056 		command.
 1057 
 1058 >> Type C-h a file <Return>.
 1059 
 1060 This displays in another window a list of all M-x commands with "file"
 1061 in their names.  You will see character-commands listed beside the
 1062 corresponding command names (such as C-x C-f beside find-file).
 1063 
 1064 >> Type C-M-v to scroll the help window.  Do this a few times.
 1065 
 1066 >> Type C-x 1 to delete the help window.
 1067 
 1068    C-h i	Read included Manuals (a.k.a. Info).  This command puts
 1069 		you into a special buffer called "*info*" where you
 1070 		can read manuals for the packages installed on your system.
 1071 		Type m emacs <Return> to read the Emacs manual.
 1072 		If you have never before used Info, type h and Emacs
 1073 		will take you on a guided tour of Info mode facilities.
 1074 		Once you are through with this tutorial, you should
 1075 		consult the Emacs Info manual as your primary documentation.
 1076 
 1077 
 1078 * MORE FEATURES
 1079 ---------------
 1080 
 1081 You can learn more about Emacs by reading its manual, either as a
 1082 printed book, or inside Emacs (use the Help menu or type C-h r).
 1083 Two features that you may like especially are completion, which saves
 1084 typing, and dired, which simplifies file handling.
 1085 
 1086 Completion is a way to avoid unnecessary typing.  For instance, if you
 1087 want to switch to the *Messages* buffer, you can type C-x b *M<Tab>
 1088 and Emacs will fill in the rest of the buffer name as far as it can
 1089 determine from what you have already typed.  Completion also works for
 1090 command names and file names.  Completion is described in the Emacs
 1091 manual in the node called "Completion".
 1092 
 1093 Dired enables you to list files in a directory (and optionally its
 1094 subdirectories), move around that list, visit, rename, delete and
 1095 otherwise operate on the files.  Dired is described in the Emacs
 1096 manual in the node called "Dired".
 1097 
 1098 The manual also describes many other Emacs features.
 1099 
 1100 
 1101 * CONCLUSION
 1102 ------------
 1103 
 1104 To exit Emacs use C-x C-c.
 1105 
 1106 This tutorial is meant to be understandable to all new users, so if
 1107 you found something unclear, don't sit and blame yourself - complain!
 1108 
 1109 
 1110 * COPYING
 1111 ---------
 1112 
 1113 This tutorial descends from a long line of Emacs tutorials
 1114 starting with the one written by Stuart Cracraft for the original Emacs.
 1115 
 1116 This version of the tutorial is a part of GNU Emacs.  It is copyrighted
 1117 and comes with permission to distribute copies on certain conditions:
 1118 
 1119   Copyright (C) 1985, 1996, 1998, 2001-2018 Free Software Foundation,
 1120   Inc.
 1121 
 1122   This file is part of GNU Emacs.
 1123 
 1124   GNU Emacs is free software: you can redistribute it and/or modify
 1125   it under the terms of the GNU General Public License as published by
 1126   the Free Software Foundation, either version 3 of the License, or
 1127   (at your option) any later version.
 1128 
 1129   GNU Emacs is distributed in the hope that it will be useful,
 1130   but WITHOUT ANY WARRANTY; without even the implied warranty of
 1131   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 1132   GNU General Public License for more details.
 1133 
 1134   You should have received a copy of the GNU General Public License
 1135   along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
 1136 
 1137 Please read the file COPYING and then do give copies of GNU Emacs to
 1138 your friends.  Help stamp out software obstructionism ("ownership") by
 1139 using, writing, and sharing free software!