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6bf7aab6 | 1 | @c This is part of the Emacs manual. |
b65d8176 | 2 | @c Copyright (C) 1985, 1986, 1987, 1993, 1994, 1995, 1997, 2000, 2001, |
8d99e09d | 3 | @c 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. |
6bf7aab6 DL |
4 | @c See file emacs.texi for copying conditions. |
5 | @node Basic, Minibuffer, Exiting, Top | |
6 | @chapter Basic Editing Commands | |
7 | ||
8 | @kindex C-h t | |
9 | @findex help-with-tutorial | |
10 | We now give the basics of how to enter text, make corrections, and | |
11 | save the text in a file. If this material is new to you, you might | |
12 | learn it more easily by running the Emacs learn-by-doing tutorial. To | |
13 | use the tutorial, run Emacs and type @kbd{Control-h t} | |
14 | (@code{help-with-tutorial}). | |
15 | ||
16 | To clear the screen and redisplay, type @kbd{C-l} (@code{recenter}). | |
17 | ||
18 | @menu | |
19 | ||
20 | * Inserting Text:: Inserting text by simply typing it. | |
21 | * Moving Point:: How to move the cursor to the place where you want to | |
22 | change something. | |
23 | * Erasing:: Deleting and killing text. | |
dc9bfb46 | 24 | * Basic Undo:: Undoing recent changes in the text. |
6bf7aab6 DL |
25 | * Files: Basic Files. Visiting, creating, and saving files. |
26 | * Help: Basic Help. Asking what a character does. | |
27 | * Blank Lines:: Commands to make or delete blank lines. | |
28 | * Continuation Lines:: Lines too wide for the screen. | |
29 | * Position Info:: What page, line, row, or column is point on? | |
30 | * Arguments:: Numeric arguments for repeating a command. | |
31 | * Repeating:: A short-cut for repeating the previous command. | |
32 | @end menu | |
33 | ||
34 | @node Inserting Text | |
35 | @section Inserting Text | |
36 | ||
37 | @cindex insertion | |
38 | @cindex graphic characters | |
39 | To insert printing characters into the text you are editing, just type | |
40 | them. This inserts the characters you type into the buffer at the | |
41 | cursor (that is, at @dfn{point}; @pxref{Point}). The cursor moves | |
42 | forward, and any text after the cursor moves forward too. If the text | |
43 | in the buffer is @samp{FOOBAR}, with the cursor before the @samp{B}, | |
44 | then if you type @kbd{XX}, you get @samp{FOOXXBAR}, with the cursor | |
45 | still before the @samp{B}. | |
46 | ||
06a97e7d RS |
47 | To @dfn{delete} text you have just inserted, use the large key |
48 | labeled @key{DEL}, @key{BACKSPACE} or @key{DELETE} which is a short | |
49 | distance above the @key{RET} or @key{ENTER} key. This is the key you | |
9ab48fa6 | 50 | normally use, outside Emacs, for erasing the last character that you |
bf1a7e14 RS |
51 | typed. Regardless of the label on that key, Emacs thinks of it as |
52 | @key{DEL}, and that's what we call it in this manual. | |
6bf7aab6 | 53 | |
06a97e7d RS |
54 | The @key{DEL} key deletes the character @emph{before} the cursor. |
55 | As a consequence, the cursor and all the characters after it move | |
56 | backwards. If you type a printing character and then type @key{DEL}, | |
57 | they cancel out. | |
58 | ||
9ab48fa6 RS |
59 | On most computers, Emacs recognizes automatically which key ought to |
60 | be @key{DEL}, and sets it up that way. But in some cases, especially | |
61 | with text-only terminals, you will need to tell Emacs which key to use | |
62 | for that purpose. If the large key not far above the @key{RET} or | |
63 | @key{ENTER} key doesn't delete backwards, you need to do this. | |
82f6ab38 | 64 | @xref{DEL Does Not Delete}, for an explanation of how. |
9ab48fa6 | 65 | |
852ae42a | 66 | Most PC keyboards have both a @key{BACKSPACE} key not far above |
83b344c5 RS |
67 | @key{RET} or @key{ENTER}, and a @key{DELETE} key elsewhere. On these |
68 | keyboards, Emacs supports when possible the usual convention that the | |
69 | @key{BACKSPACE} key deletes backwards (it is @key{DEL}), while the | |
70 | @key{DELETE} key deletes ``forwards,'' deleting the character after | |
71 | point, the one underneath the cursor, like @kbd{C-d} (see below). | |
06a97e7d | 72 | |
6bf7aab6 DL |
73 | @kindex RET |
74 | @cindex newline | |
75 | To end a line and start typing a new one, type @key{RET}. This | |
76 | inserts a newline character in the buffer. If point is in the middle of | |
1b53c26e | 77 | a line, the effect is to split the line. Typing @key{DEL} when the cursor is |
6bf7aab6 DL |
78 | at the beginning of a line deletes the preceding newline, thus joining |
79 | the line with the preceding line. | |
80 | ||
81 | Emacs can split lines automatically when they become too long, if you | |
82 | turn on a special minor mode called @dfn{Auto Fill} mode. | |
a102b252 CY |
83 | @xref{Filling}, for how to use Auto Fill mode and other modes for |
84 | @dfn{filling} text. | |
6bf7aab6 DL |
85 | |
86 | If you prefer to have text characters replace (overwrite) existing | |
87 | text rather than shove it to the right, you can enable Overwrite mode, | |
88 | a minor mode. @xref{Minor Modes}. | |
89 | ||
90 | @cindex quoting | |
91 | @kindex C-q | |
92 | @findex quoted-insert | |
93 | Direct insertion works for printing characters and @key{SPC}, but other | |
94 | characters act as editing commands and do not insert themselves. If you | |
95 | need to insert a control character or a character whose code is above 200 | |
96 | octal, you must @dfn{quote} it by typing the character @kbd{Control-q} | |
97 | (@code{quoted-insert}) first. (This character's name is normally written | |
98 | @kbd{C-q} for short.) There are two ways to use @kbd{C-q}:@refill | |
99 | ||
100 | @itemize @bullet | |
101 | @item | |
102 | @kbd{C-q} followed by any non-graphic character (even @kbd{C-g}) | |
103 | inserts that character. | |
104 | ||
105 | @item | |
106 | @kbd{C-q} followed by a sequence of octal digits inserts the character | |
107 | with the specified octal character code. You can use any number of | |
9acb8eec RS |
108 | octal digits; any non-digit terminates the sequence. If the |
109 | terminating character is @key{RET}, it serves only to terminate the | |
110 | sequence. Any other non-digit terminates the sequence and then acts | |
111 | as normal input---thus, @kbd{C-q 1 0 1 B} inserts @samp{AB}. | |
112 | ||
113 | The use of octal sequences is disabled in ordinary non-binary | |
114 | Overwrite mode, to give you a convenient way to insert a digit instead | |
115 | of overwriting with it. | |
6bf7aab6 DL |
116 | @end itemize |
117 | ||
b5d1e464 | 118 | @cindex 8-bit character codes |
6bf7aab6 | 119 | @noindent |
d3e94981 | 120 | When multibyte characters are enabled, if you specify a code in the |
093b0ab5 RS |
121 | range 0200 through 0377 octal, @kbd{C-q} assumes that you intend to |
122 | use some ISO 8859-@var{n} character set, and converts the specified | |
123 | code to the corresponding Emacs character code. @xref{Enabling | |
124 | Multibyte}. You select @emph{which} of the ISO 8859 character sets to | |
125 | use through your choice of language environment (@pxref{Language | |
126 | Environments}). | |
6bf7aab6 DL |
127 | |
128 | @vindex read-quoted-char-radix | |
129 | To use decimal or hexadecimal instead of octal, set the variable | |
130 | @code{read-quoted-char-radix} to 10 or 16. If the radix is greater than | |
131 | 10, some letters starting with @kbd{a} serve as part of a character | |
132 | code, just like digits. | |
133 | ||
134 | A numeric argument to @kbd{C-q} specifies how many copies of the | |
135 | quoted character should be inserted (@pxref{Arguments}). | |
136 | ||
137 | @findex newline | |
138 | @findex self-insert | |
139 | Customization information: @key{DEL} in most modes runs the command | |
140 | @code{delete-backward-char}; @key{RET} runs the command @code{newline}, and | |
141 | self-inserting printing characters run the command @code{self-insert}, | |
142 | which inserts whatever character was typed to invoke it. Some major modes | |
143 | rebind @key{DEL} to other commands. | |
144 | ||
145 | @node Moving Point | |
146 | @section Changing the Location of Point | |
147 | ||
148 | @cindex arrow keys | |
6bf7aab6 DL |
149 | @cindex moving point |
150 | @cindex movement | |
151 | @cindex cursor motion | |
152 | @cindex moving the cursor | |
153 | To do more than insert characters, you have to know how to move point | |
154 | (@pxref{Point}). The simplest way to do this is with arrow keys, or by | |
155 | clicking the left mouse button where you want to move to. | |
156 | ||
157 | There are also control and meta characters for cursor motion. Some | |
b96ade76 RS |
158 | are equivalent to the arrow keys (it is faster to use these control |
159 | keys than move your hand over to the arrow keys). Others do more | |
160 | sophisticated things. | |
6bf7aab6 DL |
161 | |
162 | @kindex C-a | |
163 | @kindex C-e | |
164 | @kindex C-f | |
165 | @kindex C-b | |
166 | @kindex C-n | |
167 | @kindex C-p | |
168 | @kindex M-> | |
169 | @kindex M-< | |
170 | @kindex M-r | |
06a97e7d RS |
171 | @kindex LEFT |
172 | @kindex RIGHT | |
173 | @kindex UP | |
174 | @kindex DOWN | |
c7bda15b | 175 | @findex move-beginning-of-line |
aa3dd3b5 | 176 | @findex move-end-of-line |
6bf7aab6 DL |
177 | @findex forward-char |
178 | @findex backward-char | |
179 | @findex next-line | |
180 | @findex previous-line | |
181 | @findex beginning-of-buffer | |
182 | @findex end-of-buffer | |
183 | @findex goto-char | |
184 | @findex goto-line | |
185 | @findex move-to-window-line | |
186 | @table @kbd | |
187 | @item C-a | |
c7bda15b | 188 | Move to the beginning of the line (@code{move-beginning-of-line}). |
6bf7aab6 | 189 | @item C-e |
aa3dd3b5 | 190 | Move to the end of the line (@code{move-end-of-line}). |
6bf7aab6 | 191 | @item C-f |
06a97e7d RS |
192 | Move forward one character (@code{forward-char}). The right-arrow key |
193 | does the same thing. | |
6bf7aab6 | 194 | @item C-b |
06a97e7d RS |
195 | Move backward one character (@code{backward-char}). The left-arrow |
196 | key has the same effect. | |
6bf7aab6 DL |
197 | @item M-f |
198 | Move forward one word (@code{forward-word}). | |
199 | @item M-b | |
200 | Move backward one word (@code{backward-word}). | |
201 | @item C-n | |
202 | Move down one line, vertically (@code{next-line}). This command | |
203 | attempts to keep the horizontal position unchanged, so if you start in | |
06a97e7d RS |
204 | the middle of one line, you end in the middle of the next. The |
205 | down-arrow key does the same thing. | |
6bf7aab6 | 206 | @item C-p |
06a97e7d | 207 | Move up one line, vertically (@code{previous-line}). The up-arrow key |
21c983fc | 208 | has the same effect. |
6bf7aab6 DL |
209 | @item M-r |
210 | Move point to left margin, vertically centered in the window | |
211 | (@code{move-to-window-line}). Text does not move on the screen. | |
212 | ||
213 | A numeric argument says which screen line to place point on. It counts | |
214 | screen lines down from the top of the window (zero for the top line). A | |
215 | negative argument counts lines from the bottom (@minus{}1 for the bottom | |
216 | line). | |
217 | @item M-< | |
218 | Move to the top of the buffer (@code{beginning-of-buffer}). With | |
219 | numeric argument @var{n}, move to @var{n}/10 of the way from the top. | |
220 | @xref{Arguments}, for more information on numeric arguments.@refill | |
221 | @item M-> | |
222 | Move to the end of the buffer (@code{end-of-buffer}). | |
06a97e7d | 223 | @item C-v |
1b53c26e RS |
224 | @itemx @key{PAGEDOWN} |
225 | @itemx @key{PRIOR} | |
226 | Scroll the display one screen forward, and move point if necessary to | |
227 | put it on the screen (@code{scroll-up}). This doesn't always move | |
228 | point, but it is commonly used to do so. If your keyboard has a | |
229 | @key{PAGEDOWN} or @key{PRIOR} key, it does the same thing. | |
06a97e7d RS |
230 | |
231 | Scrolling commands are further described in @ref{Scrolling}. | |
232 | @item M-v | |
1b53c26e RS |
233 | @itemx @key{PAGEUP} |
234 | @itemx @key{NEXT} | |
06a97e7d RS |
235 | Scroll one screen backward, and move point if necessary to put it on |
236 | the screen (@code{scroll-down}). This doesn't always move point, but | |
1b53c26e RS |
237 | it is commonly used to do so. If your keyboard has a @key{PAGEUP} or |
238 | @key{NEXT} key, it does the same thing. | |
6bf7aab6 DL |
239 | @item M-x goto-char |
240 | Read a number @var{n} and move point to buffer position @var{n}. | |
241 | Position 1 is the beginning of the buffer. | |
33e54c87 | 242 | @item M-g M-g |
706f4350 | 243 | @itemx M-g g |
33e54c87 | 244 | @itemx M-x goto-line |
48c13f3e LT |
245 | Read a number @var{n} and move point to the beginning of line number |
246 | @var{n}. Line 1 is the beginning of the buffer. If point is on or | |
247 | just after a number, then that is the default for @var{n}, if you just | |
248 | press @key{RET} with an empty minibuffer. | |
6bf7aab6 DL |
249 | @item C-x C-n |
250 | @findex set-goal-column | |
251 | @kindex C-x C-n | |
252 | Use the current column of point as the @dfn{semipermanent goal column} for | |
253 | @kbd{C-n} and @kbd{C-p} (@code{set-goal-column}). Henceforth, those | |
254 | commands always move to this column in each line moved into, or as | |
255 | close as possible given the contents of the line. This goal column remains | |
256 | in effect until canceled. | |
257 | @item C-u C-x C-n | |
258 | Cancel the goal column. Henceforth, @kbd{C-n} and @kbd{C-p} once | |
259 | again try to stick to a fixed horizontal position, as usual. | |
260 | @end table | |
261 | ||
262 | @vindex track-eol | |
263 | If you set the variable @code{track-eol} to a non-@code{nil} value, | |
015a26d7 | 264 | then @kbd{C-n} and @kbd{C-p}, when starting at the end of the line, move |
6bf7aab6 DL |
265 | to the end of another line. Normally, @code{track-eol} is @code{nil}. |
266 | @xref{Variables}, for how to set variables such as @code{track-eol}. | |
267 | ||
268 | @vindex next-line-add-newlines | |
c7bda15b | 269 | @kbd{C-n} normally stops at the end of the buffer when you use it on |
1b53c26e RS |
270 | the last line of the buffer. But if you set the variable |
271 | @code{next-line-add-newlines} to a non-@code{nil} value, @kbd{C-n} on | |
272 | the last line of a buffer creates an additional line at the end and | |
273 | moves down onto it. | |
6bf7aab6 | 274 | |
177c0ea7 | 275 | @node Erasing |
6bf7aab6 DL |
276 | @section Erasing Text |
277 | ||
278 | @table @kbd | |
279 | @item @key{DEL} | |
280 | Delete the character before point (@code{delete-backward-char}). | |
281 | @item C-d | |
282 | Delete the character after point (@code{delete-char}). | |
06a97e7d RS |
283 | @item @key{DELETE} |
284 | @itemx @key{BACKSPACE} | |
285 | One of these keys, whichever is the large key above the @key{RET} or | |
b96ade76 RS |
286 | @key{ENTER} key, deletes the character before point---it is @key{DEL}. |
287 | If @key{BACKSPACE} is @key{DEL}, and your keyboard also has @key{DELETE}, | |
06a97e7d | 288 | then @key{DELETE} deletes forwards, like @kbd{C-d}. |
6bf7aab6 DL |
289 | @item C-k |
290 | Kill to the end of the line (@code{kill-line}). | |
291 | @item M-d | |
292 | Kill forward to the end of the next word (@code{kill-word}). | |
293 | @item M-@key{DEL} | |
294 | Kill back to the beginning of the previous word | |
295 | (@code{backward-kill-word}). | |
296 | @end table | |
297 | ||
298 | @cindex killing characters and lines | |
299 | @cindex deleting characters and lines | |
300 | @cindex erasing characters and lines | |
301 | You already know about the @key{DEL} key which deletes the character | |
302 | before point (that is, before the cursor). Another key, @kbd{Control-d} | |
303 | (@kbd{C-d} for short), deletes the character after point (that is, the | |
304 | character that the cursor is on). This shifts the rest of the text on | |
305 | the line to the left. If you type @kbd{C-d} at the end of a line, it | |
306 | joins together that line and the next line. | |
307 | ||
308 | To erase a larger amount of text, use the @kbd{C-k} key, which kills a | |
309 | line at a time. If you type @kbd{C-k} at the beginning or middle of a | |
310 | line, it kills all the text up to the end of the line. If you type | |
311 | @kbd{C-k} at the end of a line, it joins that line and the next line. | |
312 | ||
313 | @xref{Killing}, for more flexible ways of killing text. | |
314 | ||
dc9bfb46 | 315 | @node Basic Undo |
6bf7aab6 | 316 | @section Undoing Changes |
6bf7aab6 | 317 | |
dc9bfb46 RS |
318 | Emacs records a list of changes made in the buffer text, so you can |
319 | you can undo all the recent changes, as far as the records go. | |
320 | Usually each editing command makes a separate entry in the undo | |
321 | records, but sometimes an entry covers just part of a command, and | |
322 | very simple commands may be grouped. | |
6bf7aab6 DL |
323 | |
324 | @table @kbd | |
325 | @item C-x u | |
dc9bfb46 RS |
326 | Undo one entry of the undo records---usually, one command worth |
327 | (@code{undo}). | |
6bf7aab6 | 328 | @item C-_ |
1b53c26e | 329 | @itemx C-/ |
6bf7aab6 | 330 | The same. |
6bf7aab6 DL |
331 | @end table |
332 | ||
1b53c26e RS |
333 | The command @kbd{C-x u} (or @kbd{C-_} or @kbd{C-/}) is how you undo. |
334 | The first time you give this command, it undoes the last change. | |
335 | Point moves back to where it was before the command that made the | |
336 | change. | |
6bf7aab6 | 337 | |
dc9bfb46 RS |
338 | Consecutive repetitions of @kbd{C-x u} (or its aliases) undo earlier |
339 | and earlier changes, back to the limit of the undo information | |
340 | available. If all recorded changes have already been undone, the undo | |
341 | command displays an error message and does nothing. | |
6bf7aab6 | 342 | |
b96ade76 RS |
343 | The undo command applies only to changes in the buffer; you can't |
344 | use it to undo mere cursor motion. However, some cursor motion | |
345 | commands set the mark, so if you use these commands from time to time, | |
346 | you can move back to the neighborhoods you have moved through by | |
347 | popping the mark ring (@pxref{Mark Ring}). | |
6bf7aab6 | 348 | |
6bf7aab6 DL |
349 | @node Basic Files |
350 | @section Files | |
351 | ||
352 | The commands described above are sufficient for creating and altering | |
353 | text in an Emacs buffer; the more advanced Emacs commands just make | |
b96ade76 | 354 | things easier. However, to keep any text permanently you must put it in a |
6bf7aab6 DL |
355 | @dfn{file}. Files are named units of text which are stored by the |
356 | operating system for you to retrieve later by name. To look at or use | |
357 | the contents of a file in any way, including editing the file with | |
358 | Emacs, you must specify the file name. | |
359 | ||
b96ade76 RS |
360 | Consider a file named @file{test.emacs}. (We can assume it is in |
361 | your home directory.) In Emacs, to begin editing this file, type | |
6bf7aab6 DL |
362 | |
363 | @example | |
b96ade76 | 364 | C-x C-f test.emacs @key{RET} |
6bf7aab6 DL |
365 | @end example |
366 | ||
367 | @noindent | |
368 | Here the file name is given as an @dfn{argument} to the command @kbd{C-x | |
369 | C-f} (@code{find-file}). That command uses the @dfn{minibuffer} to | |
370 | read the argument, and you type @key{RET} to terminate the argument | |
371 | (@pxref{Minibuffer}).@refill | |
372 | ||
373 | Emacs obeys the command by @dfn{visiting} the file: creating a buffer, | |
374 | copying the contents of the file into the buffer, and then displaying | |
375 | the buffer for you to edit. If you alter the text, you can @dfn{save} | |
376 | the new text in the file by typing @kbd{C-x C-s} (@code{save-buffer}). | |
377 | This makes the changes permanent by copying the altered buffer contents | |
b96ade76 RS |
378 | back into the file @file{test.emacs}. Until you save, the changes |
379 | exist only inside Emacs, and the file @file{test.emacs} is unaltered. | |
6bf7aab6 DL |
380 | |
381 | To create a file, just visit the file with @kbd{C-x C-f} as if it | |
382 | already existed. This creates an empty buffer in which you can insert | |
383 | the text you want to put in the file. The file is actually created when | |
384 | you save this buffer with @kbd{C-x C-s}. | |
385 | ||
386 | Of course, there is a lot more to learn about using files. @xref{Files}. | |
387 | ||
388 | @node Basic Help | |
389 | @section Help | |
390 | ||
391 | @cindex getting help with keys | |
392 | If you forget what a key does, you can find out with the Help | |
393 | character, which is @kbd{C-h} (or @key{F1}, which is an alias for | |
394 | @kbd{C-h}). Type @kbd{C-h k} followed by the key you want to know | |
395 | about; for example, @kbd{C-h k C-n} tells you all about what @kbd{C-n} | |
396 | does. @kbd{C-h} is a prefix key; @kbd{C-h k} is just one of its | |
397 | subcommands (the command @code{describe-key}). The other subcommands of | |
398 | @kbd{C-h} provide different kinds of help. Type @kbd{C-h} twice to get | |
399 | a description of all the help facilities. @xref{Help}.@refill | |
400 | ||
401 | @node Blank Lines | |
402 | @section Blank Lines | |
403 | ||
404 | @cindex inserting blank lines | |
405 | @cindex deleting blank lines | |
406 | Here are special commands and techniques for putting in and taking out | |
407 | blank lines. | |
408 | ||
6bf7aab6 DL |
409 | @table @kbd |
410 | @item C-o | |
411 | Insert one or more blank lines after the cursor (@code{open-line}). | |
412 | @item C-x C-o | |
413 | Delete all but one of many consecutive blank lines | |
414 | (@code{delete-blank-lines}). | |
415 | @end table | |
416 | ||
417 | @kindex C-o | |
418 | @kindex C-x C-o | |
419 | @cindex blank lines | |
420 | @findex open-line | |
421 | @findex delete-blank-lines | |
422 | When you want to insert a new line of text before an existing line, you | |
423 | can do it by typing the new line of text, followed by @key{RET}. | |
424 | However, it may be easier to see what you are doing if you first make a | |
425 | blank line and then insert the desired text into it. This is easy to do | |
426 | using the key @kbd{C-o} (@code{open-line}), which inserts a newline | |
427 | after point but leaves point in front of the newline. After @kbd{C-o}, | |
428 | type the text for the new line. @kbd{C-o F O O} has the same effect as | |
429 | @w{@kbd{F O O @key{RET}}}, except for the final location of point. | |
430 | ||
431 | You can make several blank lines by typing @kbd{C-o} several times, or | |
432 | by giving it a numeric argument to tell it how many blank lines to make. | |
c7bda15b | 433 | @xref{Arguments}, for how. If you have a fill prefix, the @kbd{C-o} |
6bf7aab6 DL |
434 | command inserts the fill prefix on the new line, when you use it at the |
435 | beginning of a line. @xref{Fill Prefix}. | |
436 | ||
437 | The easy way to get rid of extra blank lines is with the command | |
438 | @kbd{C-x C-o} (@code{delete-blank-lines}). @kbd{C-x C-o} in a run of | |
439 | several blank lines deletes all but one of them. @kbd{C-x C-o} on a | |
440 | solitary blank line deletes that blank line. When point is on a | |
441 | nonblank line, @kbd{C-x C-o} deletes any blank lines following that | |
442 | nonblank line. | |
443 | ||
444 | @node Continuation Lines | |
445 | @section Continuation Lines | |
446 | ||
447 | @cindex continuation line | |
448 | @cindex wrapping | |
449 | @cindex line wrapping | |
e56823d9 | 450 | @cindex fringes, and continuation lines |
6bf7aab6 | 451 | If you add too many characters to one line without breaking it with |
093b0ab5 RS |
452 | @key{RET}, the line grows to occupy two (or more) lines on the screen. |
453 | On graphical displays, Emacs indicates line wrapping with small bent | |
454 | arrows in the fringes to the left and right of the window. On | |
455 | text-only terminals, Emacs displays a @samp{\} character at the right | |
456 | margin of a screen line if it is not the last in its text line. This | |
457 | @samp{\} character says that the following screen line is not really a | |
458 | distinct line in the text, just a @dfn{continuation} of a line too | |
459 | long to fit the screen. Continuation is also called @dfn{line | |
460 | wrapping}. | |
461 | ||
462 | When line wrapping occurs before a character that is wider than one | |
463 | column, some columns at the end of the previous screen line may be | |
464 | ``empty.'' In this case, Emacs displays additional @samp{\} | |
465 | characters in the ``empty'' columns, just before the @samp{\} | |
466 | character that indicates continuation. | |
6bf7aab6 | 467 | |
a102b252 CY |
468 | Continued lines can be rather difficult to read, since each line is |
469 | typically broken in the middle of a word. You can have Emacs insert a | |
470 | newline automatically when a line gets too long, by using Auto Fill | |
471 | mode. Another approach, intermediate between continued lines and Auto | |
472 | Fill mode, is Long Lines mode, which ensures that wrapping only occurs | |
473 | in the spaces between words. @xref{Filling}. | |
6bf7aab6 | 474 | |
6bf7aab6 | 475 | @cindex truncation |
e56823d9 | 476 | @cindex line truncation, and fringes |
a102b252 CY |
477 | Emacs can also display long lines by @dfn{truncation}. This means |
478 | that all the characters that do not fit in the width of the screen or | |
479 | window do not appear at all. @samp{$} in the last column or a small | |
480 | straight arrow in the fringe to the right of the window indicates a | |
481 | truncated line. | |
ab527690 RS |
482 | |
483 | @xref{Display Custom}, for more information about line truncation, | |
484 | and other variables that affect how text is displayed. | |
6bf7aab6 DL |
485 | |
486 | @node Position Info | |
487 | @section Cursor Position Information | |
488 | ||
489 | Here are commands to get information about the size and position of | |
490 | parts of the buffer, and to count lines. | |
491 | ||
492 | @table @kbd | |
493 | @item M-x what-page | |
093b0ab5 | 494 | Display the page number of point, and the line number within the page. |
6bf7aab6 | 495 | @item M-x what-line |
093b0ab5 | 496 | Display the line number of point in the buffer. |
6bf7aab6 | 497 | @item M-x line-number-mode |
67675c0f DL |
498 | @itemx M-x column-number-mode |
499 | Toggle automatic display of current line number or column number. | |
500 | @xref{Optional Mode Line}. | |
6bf7aab6 | 501 | @item M-= |
093b0ab5 | 502 | Display the number of lines in the current region (@code{count-lines-region}). |
6bf7aab6 DL |
503 | @xref{Mark}, for information about the region. |
504 | @item C-x = | |
093b0ab5 | 505 | Display the character code of character after point, character position of |
6bf7aab6 | 506 | point, and column of point (@code{what-cursor-position}). |
67675c0f | 507 | @item M-x hl-line-mode |
83440f52 EZ |
508 | Enable or disable highlighting of the current line. @xref{Cursor |
509 | Display}. | |
ffa11cf3 LK |
510 | @item M-x size-indication-mode |
511 | Toggle automatic display of the size of the buffer. | |
512 | @xref{Optional Mode Line}. | |
6bf7aab6 DL |
513 | @end table |
514 | ||
515 | @findex what-page | |
516 | @findex what-line | |
517 | @cindex line number commands | |
518 | @cindex location of point | |
519 | @cindex cursor location | |
520 | @cindex point location | |
706f4350 LT |
521 | @kbd{M-x what-line} computes the current line number and displays it |
522 | in the echo area. You can also see the current line number in the | |
523 | mode line; see @ref{Mode Line}. If you narrow the buffer, then the | |
524 | line number in the mode line is relative to the accessible portion | |
525 | (@pxref{Narrowing}). By contrast, @code{what-line} shows both the | |
526 | line number relative to the narrowed region and the line number | |
527 | relative to the whole buffer. | |
6bf7aab6 | 528 | |
9acb8eec | 529 | @kbd{M-x what-page} counts pages from the beginning of the file, and |
1ba2ce68 RS |
530 | counts lines within the page, showing both numbers in the echo area. |
531 | @xref{Pages}. | |
6bf7aab6 DL |
532 | |
533 | @kindex M-= | |
534 | @findex count-lines-region | |
535 | While on this subject, we might as well mention @kbd{M-=} (@code{count-lines-region}), | |
1ba2ce68 | 536 | which displays the number of lines in the region (@pxref{Mark}). |
6bf7aab6 DL |
537 | @xref{Pages}, for the command @kbd{C-x l} which counts the lines in the |
538 | current page. | |
539 | ||
540 | @kindex C-x = | |
541 | @findex what-cursor-position | |
6cf1bebc RS |
542 | The command @kbd{C-x =} (@code{what-cursor-position}) shows what |
543 | column the cursor is in, and other miscellaneous information about | |
544 | point and the character after it. It displays a line in the echo area | |
545 | that looks like this: | |
6bf7aab6 DL |
546 | |
547 | @smallexample | |
fe7c712e | 548 | Char: c (99, #o143, #x63) point=28062 of 36168 (78%) column=53 |
6bf7aab6 DL |
549 | @end smallexample |
550 | ||
6bf7aab6 DL |
551 | The four values after @samp{Char:} describe the character that follows |
552 | point, first by showing it and then by giving its character code in | |
fe7c712e | 553 | decimal, octal and hex. For a non-@acronym{ASCII} multibyte character, these are |
339ef8ce | 554 | followed by @samp{file} and the character's representation, in hex, in |
6bf7aab6 DL |
555 | the buffer's coding system, if that coding system encodes the character |
556 | safely and with a single byte (@pxref{Coding Systems}). If the | |
339ef8ce KH |
557 | character's encoding is longer than one byte, Emacs shows @samp{file ...}. |
558 | ||
559 | However, if the character displayed is in the range 0200 through | |
170e42a1 KH |
560 | 0377 octal, it may actually stand for an invalid UTF-8 byte read from |
561 | a file. In Emacs, that byte is represented as a sequence of 8-bit | |
562 | characters, but all of them together display as the original invalid | |
563 | byte, in octal code. In this case, @kbd{C-x =} shows @samp{part of | |
564 | display ...} instead of @samp{file}. | |
6bf7aab6 DL |
565 | |
566 | @samp{point=} is followed by the position of point expressed as a character | |
567 | count. The front of the buffer counts as position 1, one character later | |
568 | as 2, and so on. The next, larger, number is the total number of characters | |
569 | in the buffer. Afterward in parentheses comes the position expressed as a | |
570 | percentage of the total size. | |
571 | ||
fe7c712e | 572 | @samp{column=} is followed by the horizontal position of point, in |
6bf7aab6 DL |
573 | columns from the left edge of the window. |
574 | ||
575 | If the buffer has been narrowed, making some of the text at the | |
1ba2ce68 | 576 | beginning and the end temporarily inaccessible, @kbd{C-x =} displays |
6bf7aab6 DL |
577 | additional text describing the currently accessible range. For example, it |
578 | might display this: | |
579 | ||
580 | @smallexample | |
fe7c712e | 581 | Char: C (67, #o103, #x43) point=252 of 889 (28%) <231-599> column=0 |
6bf7aab6 DL |
582 | @end smallexample |
583 | ||
584 | @noindent | |
585 | where the two extra numbers give the smallest and largest character | |
586 | position that point is allowed to assume. The characters between those | |
587 | two positions are the accessible ones. @xref{Narrowing}. | |
588 | ||
589 | If point is at the end of the buffer (or the end of the accessible | |
590 | part), the @w{@kbd{C-x =}} output does not describe a character after | |
591 | point. The output might look like this: | |
592 | ||
593 | @smallexample | |
fe7c712e | 594 | point=36169 of 36168 (EOB) column=0 |
6bf7aab6 DL |
595 | @end smallexample |
596 | ||
01005464 | 597 | @cindex character set of character at point |
7923e3c2 | 598 | @cindex font of character at point |
01005464 | 599 | @cindex text properties at point |
c7bda15b | 600 | @w{@kbd{C-u C-x =}} displays the following additional information about a |
27a132c3 KH |
601 | character. |
602 | ||
603 | @itemize @bullet | |
604 | @item | |
42a99593 | 605 | The character set name, and the codes that identify the character |
27a132c3 KH |
606 | within that character set; @acronym{ASCII} characters are identified |
607 | as belonging to the @code{ascii} character set. | |
608 | ||
609 | @item | |
610 | The character's syntax and categories. | |
611 | ||
612 | @item | |
42a99593 RS |
613 | The character's encodings, both internally in the buffer, and externally |
614 | if you were to save the file. | |
27a132c3 KH |
615 | |
616 | @item | |
42a99593 RS |
617 | What to type to input the character in the current input method |
618 | (if it supports the character). | |
27a132c3 KH |
619 | |
620 | @item | |
bbf0fec6 RS |
621 | If you are running Emacs on a graphical display, the font name and |
622 | glyph code for the character. If you are running Emacs on a text-only | |
623 | terminal, the code(s) sent to the terminal. | |
27a132c3 KH |
624 | |
625 | @item | |
626 | The character's text properties (@pxref{Text Properties,,, | |
6cf1bebc RS |
627 | elisp, the Emacs Lisp Reference Manual}), and any overlays containing it |
628 | (@pxref{Overlays,,, elisp, the same manual}). | |
27a132c3 KH |
629 | @end itemize |
630 | ||
6480c8b4 | 631 | Here's an example showing the Latin-1 character A with grave accent, |
27a132c3 | 632 | in a buffer whose coding system is @code{iso-latin-1}, whose |
6480c8b4 | 633 | terminal coding system is @code{iso-latin-1} (so the terminal actually |
01005464 EZ |
634 | displays the character as @samp{@`A}), and which has font-lock-mode |
635 | (@pxref{Font Lock}) enabled: | |
6bf7aab6 | 636 | |
9acb8eec | 637 | @smallexample |
fe7c712e | 638 | character: @`A (2240, #o4300, #x8c0, U+00C0) |
3f3015e4 | 639 | charset: latin-iso8859-1 |
27a132c3 | 640 | (Right-Hand Part of Latin Alphabet 1@dots{} |
3f3015e4 | 641 | code point: #x40 |
27a132c3 KH |
642 | syntax: w which means: word |
643 | category: l:Latin | |
3f3015e4 | 644 | to input: type "`A" with latin-1-prefix |
fe7c712e | 645 | buffer code: #x81 #xC0 |
3f3015e4 | 646 | file code: #xC0 (encoded by coding system iso-latin-1) |
fe7c712e | 647 | display: terminal code #xC0 |
27a132c3 KH |
648 | |
649 | There are text properties here: | |
650 | fontified t | |
9acb8eec | 651 | @end smallexample |
6bf7aab6 DL |
652 | |
653 | @node Arguments | |
654 | @section Numeric Arguments | |
655 | @cindex numeric arguments | |
656 | @cindex prefix arguments | |
4946337d | 657 | @cindex arguments to commands |
6bf7aab6 DL |
658 | |
659 | In mathematics and computer usage, the word @dfn{argument} means | |
660 | ``data provided to a function or operation.'' You can give any Emacs | |
661 | command a @dfn{numeric argument} (also called a @dfn{prefix argument}). | |
662 | Some commands interpret the argument as a repetition count. For | |
663 | example, @kbd{C-f} with an argument of ten moves forward ten characters | |
664 | instead of one. With these commands, no argument is equivalent to an | |
665 | argument of one. Negative arguments tell most such commands to move or | |
666 | act in the opposite direction. | |
667 | ||
668 | @kindex M-1 | |
669 | @kindex M-@t{-} | |
670 | @findex digit-argument | |
671 | @findex negative-argument | |
1b53c26e RS |
672 | If your terminal keyboard has a @key{META} key (labeled @key{ALT} on |
673 | PC keyboards), the easiest way to specify a numeric argument is to | |
674 | type digits and/or a minus sign while holding down the @key{META} key. | |
675 | For example, | |
a1f6ea55 | 676 | |
6bf7aab6 DL |
677 | @example |
678 | M-5 C-n | |
679 | @end example | |
a1f6ea55 | 680 | |
6bf7aab6 DL |
681 | @noindent |
682 | would move down five lines. The characters @kbd{Meta-1}, @kbd{Meta-2}, | |
683 | and so on, as well as @kbd{Meta--}, do this because they are keys bound | |
684 | to commands (@code{digit-argument} and @code{negative-argument}) that | |
a1f6ea55 EZ |
685 | are defined to contribute to an argument for the next command. |
686 | @kbd{Meta--} without digits normally means @minus{}1. Digits and | |
687 | @kbd{-} modified with Control, or Control and Meta, also specify numeric | |
688 | arguments. | |
6bf7aab6 DL |
689 | |
690 | @kindex C-u | |
691 | @findex universal-argument | |
692 | Another way of specifying an argument is to use the @kbd{C-u} | |
693 | (@code{universal-argument}) command followed by the digits of the | |
694 | argument. With @kbd{C-u}, you can type the argument digits without | |
695 | holding down modifier keys; @kbd{C-u} works on all terminals. To type a | |
696 | negative argument, type a minus sign after @kbd{C-u}. Just a minus sign | |
697 | without digits normally means @minus{}1. | |
698 | ||
b96ade76 RS |
699 | @kbd{C-u} without digits or minus sign has the special meaning of |
700 | ``four times'': it multiplies the argument for the next command by | |
701 | four. @kbd{C-u C-u} multiplies it by sixteen. Thus, @kbd{C-u C-u | |
702 | C-f} moves forward sixteen characters. This is a good way to move | |
703 | forward ``fast,'' since it moves about 1/5 of a line in the usual size | |
704 | screen. Other useful combinations are @kbd{C-u C-n}, @kbd{C-u C-u | |
705 | C-n} (move down a good fraction of a screen), @kbd{C-u C-u C-o} (make | |
706 | ``a lot'' of blank lines), and @kbd{C-u C-k} (kill four lines).@refill | |
6bf7aab6 DL |
707 | |
708 | Some commands care only about whether there is an argument, and not about | |
709 | its value. For example, the command @kbd{M-q} (@code{fill-paragraph}) with | |
710 | no argument fills text; with an argument, it justifies the text as well. | |
711 | (@xref{Filling}, for more information on @kbd{M-q}.) Plain @kbd{C-u} is a | |
712 | handy way of providing an argument for such commands. | |
713 | ||
714 | Some commands use the value of the argument as a repeat count, but do | |
715 | something peculiar when there is no argument. For example, the command | |
716 | @kbd{C-k} (@code{kill-line}) with argument @var{n} kills @var{n} lines, | |
717 | including their terminating newlines. But @kbd{C-k} with no argument is | |
718 | special: it kills the text up to the next newline, or, if point is right at | |
719 | the end of the line, it kills the newline itself. Thus, two @kbd{C-k} | |
720 | commands with no arguments can kill a nonblank line, just like @kbd{C-k} | |
721 | with an argument of one. (@xref{Killing}, for more information on | |
722 | @kbd{C-k}.)@refill | |
723 | ||
724 | A few commands treat a plain @kbd{C-u} differently from an ordinary | |
725 | argument. A few others may treat an argument of just a minus sign | |
726 | differently from an argument of @minus{}1. These unusual cases are | |
1b53c26e RS |
727 | described when they come up; they are always for reasons of |
728 | convenience of use of the individual command, and they are documented | |
729 | in the command's documentation string. | |
6bf7aab6 DL |
730 | |
731 | You can use a numeric argument to insert multiple copies of a | |
732 | character. This is straightforward unless the character is a digit; for | |
733 | example, @kbd{C-u 6 4 a} inserts 64 copies of the character @samp{a}. | |
734 | But this does not work for inserting digits; @kbd{C-u 6 4 1} specifies | |
735 | an argument of 641, rather than inserting anything. To separate the | |
736 | digit to insert from the argument, type another @kbd{C-u}; for example, | |
737 | @kbd{C-u 6 4 C-u 1} does insert 64 copies of the character @samp{1}. | |
738 | ||
739 | We use the term ``prefix argument'' as well as ``numeric argument'' to | |
740 | emphasize that you type the argument before the command, and to | |
741 | distinguish these arguments from minibuffer arguments that come after | |
742 | the command. | |
743 | ||
744 | @node Repeating | |
745 | @section Repeating a Command | |
746 | @cindex repeating a command | |
747 | ||
9b3ae7e4 RS |
748 | Many simple commands, such as those invoked with a single key or |
749 | with @kbd{M-x @var{command-name} @key{RET}}, can be repeated by | |
750 | invoking them with a numeric argument that serves as a repeat count | |
751 | (@pxref{Arguments}). However, if the command you want to repeat | |
752 | prompts for some input, or uses a numeric argument in another way, | |
753 | repetition using a numeric argument might be problematical. | |
68b7eaa9 | 754 | |
6bf7aab6 DL |
755 | @kindex C-x z |
756 | @findex repeat | |
757 | The command @kbd{C-x z} (@code{repeat}) provides another way to repeat | |
758 | an Emacs command many times. This command repeats the previous Emacs | |
759 | command, whatever that was. Repeating a command uses the same arguments | |
760 | that were used before; it does not read new arguments each time. | |
761 | ||
762 | To repeat the command more than once, type additional @kbd{z}'s: each | |
763 | @kbd{z} repeats the command one more time. Repetition ends when you | |
764 | type a character other than @kbd{z}, or press a mouse button. | |
765 | ||
766 | For example, suppose you type @kbd{C-u 2 0 C-d} to delete 20 | |
767 | characters. You can repeat that command (including its argument) three | |
768 | additional times, to delete a total of 80 characters, by typing @kbd{C-x | |
769 | z z z}. The first @kbd{C-x z} repeats the command once, and each | |
770 | subsequent @kbd{z} repeats it once again. | |
771 | ||
ab5796a9 MB |
772 | @ignore |
773 | arch-tag: cda8952a-c439-41c1-aecf-4bc0d6482956 | |
774 | @end ignore |