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1 1 @c This is part of the XEmacs manual.
2 @c Copyright (C) 1985, 86, 87, 93, 94, 95, 1997 Free Software Foundation, Inc.
3 @c See file xemacs.texi for copying conditions.
2 @node Basic, Undo, Startup Paths, Top 4 @node Basic, Undo, Startup Paths, Top
3 @chapter Basic Editing Commands 5 @chapter Basic Editing Commands
4 6
5 @kindex C-h t 7 @kindex C-h t
6 @findex help-with-tutorial 8 @findex help-with-tutorial
7 We now give the basics of how to enter text, make corrections, and 9 We now give the basics of how to enter text, make corrections, and
8 save the text in a file. If this material is new to you, you might 10 save the text in a file. If this material is new to you, you might
9 learn it more easily by running the Emacs learn-by-doing tutorial. To 11 learn it more easily by running the Emacs learn-by-doing tutorial. To
10 do this, type @kbd{Control-h t} (@code{help-with-tutorial}). 12 use the tutorial, run Emacs and type @kbd{Control-h t}
11 13 (@code{help-with-tutorial}). You can also use @b{Tutorials} item from
14 the @b{Help} menu.
15
16 XEmacs comes with many translations of tutorial. If your XEmacs is with
17 MULE and you set up language environment correctly, XEmacs choses right
18 tutorial when available (@pxref{Language Environments}). If you want
19 specific translation, give @kbd{C-h t} a prefix argument, like @kbd{C-u
20 C-h t}.
21
22 To clear the screen and redisplay, type @kbd{C-l} (@code{recenter}).
23
24 @menu
25
26 * Inserting Text:: Inserting text by simply typing it.
27 * Moving Point:: How to move the cursor to the place where you want to
28 change something.
29 * Erasing:: Deleting and killing text.
30 * Files: Basic Files. Visiting, creating, and saving files.
31 * Help: Basic Help. Asking what a character does.
32 * Blank Lines:: Commands to make or delete blank lines.
33 * Continuation Lines:: Lines too wide for the screen.
34 * Position Info:: What page, line, row, or column is point on?
35 * Arguments:: Numeric arguments for repeating a command.
36 @c * Repeating:: A short-cut for repeating the previous command.
37 @end menu
38
39 @node Inserting Text, Moving Point, , Basic
12 @section Inserting Text 40 @section Inserting Text
13 41
14 @cindex insertion 42 @cindex insertion
15 @cindex point 43 @cindex point
16 @cindex cursor 44 @cindex cursor
17 @cindex graphic characters 45 @cindex graphic characters
18 To insert printing characters into the text you are editing, just type 46 To insert printing characters into the text you are editing, just type
19 them. This inserts the characters into the buffer at the cursor (that 47 them. This inserts the characters you type into the buffer at the
20 is, at @dfn{point}; @pxref{Point}). The cursor moves forward. Any 48 cursor (that is, at @dfn{point}; @pxref{Point}). The cursor moves
21 characters after the cursor move forward too. If the text in the buffer 49 forward, and any text after the cursor moves forward too. If the text
22 is @samp{FOOBAR}, with the cursor before the @samp{B}, and you type 50 in the buffer is @samp{FOOBAR}, with the cursor before the @samp{B},
23 @kbd{XX}, the result is @samp{FOOXXBAR}, with the cursor still before the 51 then if you type @kbd{XX}, you get @samp{FOOXXBAR}, with the cursor
24 @samp{B}. 52 still before the @samp{B}.
25 53
26 @kindex DEL 54 @kindex BS
27 @cindex deletion 55 @cindex deletion
28 To @dfn{delete} text you have just inserted, use @key{DEL}. 56 To @dfn{delete} text you have just inserted, use @key{BS}. @key{BS}
29 @key{DEL} deletes the character @var{before} the cursor (not the one 57 deletes the character @emph{before} the cursor (not the one that the
30 that the cursor is on top of or under; that is the character @var{after} 58 cursor is on top of or under; that is the character @var{after} the
31 the cursor). The cursor and all characters after it move backwards. 59 cursor). The cursor and all characters after it move backwards.
32 Therefore, if you type a printing character and then type @key{DEL}, 60 Therefore, if you type a printing character and then type @key{BS}, they
33 they cancel out. 61 cancel out.
34 62
35 @kindex RET 63 @kindex RET
36 @cindex newline 64 @cindex newline
37 To end a line and start typing a new one, type @key{RET}. This 65 To end a line and start typing a new one, type @key{RET}. This
38 inserts a newline character in the buffer. If point is in the middle of 66 inserts a newline character in the buffer. If point is in the middle of
39 a line, @key{RET} splits the line. Typing @key{DEL} when the cursor is 67 a line, @key{RET} splits the line. Typing @key{DEL} when the cursor is
40 at the beginning of a line rubs out the newline before the line, thus 68 at the beginning of a line deletes the preceding newline, thus joining
41 joining the line with the preceding line. 69 the line with the preceding line.
42 70
43 Emacs automatically splits lines when they become too long, if you 71 Emacs can split lines automatically when they become too long, if you
44 turn on a special mode called @dfn{Auto Fill} mode. @xref{Filling}, for 72 turn on a special minor mode called @dfn{Auto Fill} mode.
45 information on using Auto Fill mode. 73 @xref{Filling}, for how to use Auto Fill mode.
46 74
47 @findex delete-backward-char 75 If you prefer to have text characters replace (overwrite) existing
76 text rather than shove it to the right, you can enable Overwrite mode,
77 a minor mode. @xref{Minor Modes}.
78
79 @cindex quoting
80 @kindex C-q
81 @findex quoted-insert
82 Direct insertion works for printing characters and @key{SPC}, but other
83 characters act as editing commands and do not insert themselves. If you
84 need to insert a control character or a character whose code is above 200
85 octal, you must @dfn{quote} it by typing the character @kbd{Control-q}
86 (@code{quoted-insert}) first. (This character's name is normally written
87 @kbd{C-q} for short.) There are two ways to use @kbd{C-q}:
88
89 @itemize @bullet
90 @item
91 @kbd{C-q} followed by any non-graphic character (even @kbd{C-g})
92 inserts that character.
93
94 @item
95 @kbd{C-q} followed by a sequence of octal digits inserts the character
96 with the specified octal character code. You can use any number of
97 octal digits; any non-digit terminates the sequence. If the terminating
98 character is @key{RET}, it serves only to terminate the sequence; any
99 other non-digit is itself used as input after terminating the sequence.
100 (The use of octal sequences is disabled in ordinary non-binary Overwrite
101 mode, to give you a convenient way to insert a digit instead of
102 overwriting with it.)
103 @end itemize
104
105 @noindent
106 A numeric argument to @kbd{C-q} specifies how many copies of the quoted
107 character should be inserted (@pxref{Arguments}).
108
109 @findex backward-or-forward-delete-char
48 @findex newline 110 @findex newline
49 @findex self-insert 111 @findex self-insert
50 Customization information: @key{DEL}, in most modes, runs the command 112 Customization information: @key{DEL}, in most modes, runs the command
51 @code{delete-backward-char}; @key{RET} runs the command @code{newline}, 113 @code{backward-or-forward-delete-char}; @key{RET} runs the command
52 and self-inserting printing characters run the command 114 @code{newline}, and self-inserting printing characters run the command
53 @code{self-insert}, which inserts whatever character was typed to invoke 115 @code{self-insert}, which inserts whatever character was typed to invoke
54 it. Some major modes rebind @key{DEL} to other commands. 116 it. Some major modes rebind @key{DEL} to other commands.
55 117
56 @cindex quoting 118 @node Moving Point, Erasing, Inserting Text, Basic
57 @kindex C-q
58 @findex quoted-insert
59 Direct insertion works for printing characters and @key{SPC}, but
60 other characters act as editing commands and do not insert themselves.
61 If you need to insert a control character or a character whose code is
62 above 200 octal, you must @dfn{quote} it by typing the character
63 @kbd{control-q} (@code{quoted-insert}) first. There are two ways to use
64 @kbd{C-q}:@refill
65
66 @itemize @bullet
67 @item
68 @kbd{Control-q} followed by any non-graphic character (even @kbd{C-g})
69 inserts that character.
70 @item
71 @kbd{Control-q} followed by three octal digits inserts the character
72 with the specified character code.
73 @end itemize
74
75 @noindent
76 A numeric argument to @kbd{C-q} specifies how many copies of the quoted
77 character should be inserted (@pxref{Arguments}).
78
79 If you prefer to have text characters replace (overwrite) existing
80 text instead of moving it to the right, you can enable Overwrite mode, a
81 minor mode. @xref{Minor Modes}.
82
83 @section Changing the Location of Point 119 @section Changing the Location of Point
84 120
121 @cindex arrow keys
122 @kindex LEFT
123 @kindex RIGHT
124 @kindex UP
125 @kindex DOWN
126 @cindex moving point
127 @cindex movement
128 @cindex cursor motion
129 @cindex moving the cursor
85 To do more than insert characters, you have to know how to move point 130 To do more than insert characters, you have to know how to move point
86 (@pxref{Point}). Here are a few of the available commands. 131 (@pxref{Point}). The simplest way to do this is with arrow keys, or by
132 clicking the left mouse button where you want to move to.
87 133
88 NOTE: Many of the following commands have two versions, one that uses 134 NOTE: Many of the following commands have two versions, one that uses
89 the function keys (e.g. @key{LEFT} or @key{END}) and one that doesn't. 135 the function keys (e.g. @key{LEFT} or @key{END}) and one that doesn't.
90 The former versions may only be available on X terminals (i.e. not on 136 The former versions may only be available on X terminals (i.e. not on
91 TTY's), but the latter are available on all terminals. 137 TTY's), but the latter are available on all terminals.
147 @item M-b 193 @item M-b
148 @itemx C-LEFT 194 @itemx C-LEFT
149 Move backward one word (@code{backward-word}). 195 Move backward one word (@code{backward-word}).
150 @item C-n 196 @item C-n
151 @itemx DOWN 197 @itemx DOWN
152 Move down one line, vertically (@code{next-line}). This command attempts to keep the horizontal position unchanged, so if you start in the middle of one line, you end in the middle of the next. When on the last line of text, @kbd{C-n} creates a new line and moves onto it. 198 Move down one line, vertically (@code{next-line}). This command
199 attempts to keep the horizontal position unchanged, so if you start in
200 the middle of one line, you end in the middle of the next. When on the
201 last line of text, @kbd{C-n} creates a new line and moves onto it.
153 @item C-p 202 @item C-p
154 @itemx UP 203 @itemx UP
155 Move up one line, vertically (@code{previous-line}). 204 Move up one line, vertically (@code{previous-line}).
156 @item C-v 205 @item C-v
157 @itemx PGDN 206 @itemx PGDN
161 Move up one page, vertically (@code{scroll-down}). 210 Move up one page, vertically (@code{scroll-down}).
162 @item C-l 211 @item C-l
163 Clear the frame and reprint everything (@code{recenter}). Text moves 212 Clear the frame and reprint everything (@code{recenter}). Text moves
164 on the frame to bring point to the center of the window. 213 on the frame to bring point to the center of the window.
165 @item M-r 214 @item M-r
166 Move point to left margin on the line halfway down the frame or 215 Move point to left margin, vertically centered in the window
167 window (@code{move-to-window-line}). Text does not move on the 216 (@code{move-to-window-line}). Text does not move on the screen.
168 frame. A numeric argument says how many screen lines down from the 217
169 top of the window (zero for the top). A negative argument counts from 218 A numeric argument says which screen line to place point on. It counts
170 the bottom (@minus{}1 for the bottom). 219 screen lines down from the top of the window (zero for the top line). A
220 negative argument counts lines from the bottom (@minus{}1 for the bottom
221 line).
171 @item C-t 222 @item C-t
172 Transpose two characters, the ones before and after the cursor 223 Transpose two characters, the ones before and after the cursor
173 @*(@code{transpose-chars}). 224 (@code{transpose-chars}).
174 @item M-< 225 @item M-<
175 @itemx C-HOME 226 @itemx C-HOME
176 Move to the top of the buffer (@code{beginning-of-buffer}). With 227 Move to the top of the buffer (@code{beginning-of-buffer}). With
177 numeric argument @var{n}, move to @var{n}/10 of the way from the top. 228 numeric argument @var{n}, move to @var{n}/10 of the way from the top.
178 @xref{Arguments}, for more information on numeric arguments.@refill 229 @xref{Arguments}, for more information on numeric arguments.@refill
179 @item M-> 230 @item M->
180 @itemx C-END 231 @itemx C-END
181 Move to the end of the buffer (@code{end-of-buffer}). 232 Move to the end of the buffer (@code{end-of-buffer}).
182 @item M-x goto-char 233 @item M-x goto-char
183 Read a number @var{n} and move the cursor to character number @var{n}. 234 Read a number @var{n} and move point to buffer position @var{n}.
184 Position 1 is the beginning of the buffer. 235 Position 1 is the beginning of the buffer.
185 @item M-g 236 @item M-g
186 Read a number @var{n} and move cursor to line number @var{n} 237 Read a number @var{n} and move point to line number @var{n}
187 (@code{goto-line}). Line 1 is the beginning of the buffer. 238 (@code{goto-line}). Line 1 is the beginning of the buffer.
188 @item C-x C-n 239 @c @item C-x C-n
240 @item M-x set-goal-column
189 @findex set-goal-column 241 @findex set-goal-column
190 Use the current column of point as the @dfn{semi-permanent goal column} for 242 Use the current column of point as the @dfn{semi-permanent goal column} for
191 @kbd{C-n} and @kbd{C-p} (@code{set-goal-column}). Henceforth, those 243 @kbd{C-n} and @kbd{C-p} (@code{set-goal-column}). Henceforth, those
192 commands always move to this column in each line moved into, or as 244 commands always move to this column in each line moved into, or as
193 close as possible given the contents of the line. This goal column remains 245 close as possible given the contents of the line. This goal column remains
194 in effect until canceled. 246 in effect until canceled.
195 @item C-u C-x C-n 247 @c @item C-u C-x C-n
248 @item C-u M-x set-goal-column
196 Cancel the goal column. Henceforth, @kbd{C-n} and @kbd{C-p} once 249 Cancel the goal column. Henceforth, @kbd{C-n} and @kbd{C-p} once
197 again try to avoid changing the horizontal position, as usual. 250 again try to avoid changing the horizontal position, as usual.
198 @end table 251 @end table
199 252
200 @vindex track-eol 253 @vindex track-eol
201 If you set the variable @code{track-eol} to a non-@code{nil} value, 254 If you set the variable @code{track-eol} to a non-@code{nil} value,
202 @kbd{C-n} and @kbd{C-p} move to the end of the line when at the end of 255 then @kbd{C-n} and @kbd{C-p} when at the end of the starting line move
203 the starting line. By default, @code{track-eol} is @code{nil}. 256 to the end of another line. Normally, @code{track-eol} is @code{nil}.
204 257 @xref{Variables}, for how to set variables such as @code{track-eol}.
258
259 @vindex next-line-add-newlines
260 Normally, @kbd{C-n} on the last line of a buffer appends a newline to
261 it. If the variable @code{next-line-add-newlines} is @code{nil}, then
262 @kbd{C-n} gets an error instead (like @kbd{C-p} on the first line).
263
264 @node Erasing, Basic Files, Moving Point, Basic
205 @section Erasing Text 265 @section Erasing Text
206 266
207 @table @kbd 267 @table @kbd
208 @item @key{DEL} 268 @item @key{DEL}
209 Delete the character before the cursor (@code{delete-backward-char}). 269 Delete the character before or after point
270 (@code{backward-or-forward-delete-char}). You can customize
271 this behavior by setting the variable @code{delete-key-deletes-forward}.
210 @item C-d 272 @item C-d
211 Delete the character after the cursor (@code{delete-char}). 273 Delete the character after point (@code{delete-char}).
212 @item C-k 274 @item C-k
213 Kill to the end of the line (@code{kill-line}). 275 Kill to the end of the line (@code{kill-line}).
214 @item M-d 276 @item M-d
215 Kill forward to the end of the next word (@code{kill-word}). 277 Kill forward to the end of the next word (@code{kill-word}).
216 @item M-@key{DEL} 278 @item M-@key{DEL}
217 Kill back to the beginning of the previous word 279 Kill back to the beginning of the previous word
218 (@code{backward-kill-word}). 280 (@code{backward-kill-word}).
219 @end table 281 @end table
220 282
221 In contrast to the @key{DEL} key, which deletes the character before 283 @cindex killing characters and lines
222 the cursor, @kbd{Control-d} deletes the character after the cursor, 284 @cindex deleting characters and lines
223 causing the rest of the text on the line to shift left. If 285 @cindex erasing characters and lines
224 @kbd{Control-d} is typed at the end of a line, that line and the next 286 You already know about the @key{DEL} key which deletes the character
225 line are joined. 287 before point (that is, before the cursor). Another key, @kbd{Control-d}
226 288 (@kbd{C-d} for short), deletes the character after point (that is, the
227 To erase a larger amount of text, use @kbd{Control-k}, which kills a 289 character that the cursor is on). This shifts the rest of the text on
228 line at a time. If you use @kbd{C-k} at the beginning or in the middle 290 the line to the left. If you type @kbd{C-d} at the end of a line, it
229 of a line, it kills all the text up to the end of the line. If you use 291 joins together that line and the next line.
230 @kbd{C-k} at the end of a line, it joins that line and the next 292
231 line. 293 To erase a larger amount of text, use the @kbd{C-k} key, which kills a
294 line at a time. If you type @kbd{C-k} at the beginning or middle of a
295 line, it kills all the text up to the end of the line. If you type
296 @kbd{C-k} at the end of a line, it joins that line and the next line.
232 297
233 @xref{Killing}, for more flexible ways of killing text. 298 @xref{Killing}, for more flexible ways of killing text.
234 299
300 @node Basic Files, Basic Help, Erasing, Basic
235 @section Files 301 @section Files
236 302
237 @cindex files 303 @cindex files
238 The commands above are sufficient for creating and altering text in an 304 The commands described above are sufficient for creating and altering
239 Emacs buffer. More advanced Emacs commands just make things easier. But 305 text in an Emacs buffer; the more advanced Emacs commands just make
240 to keep any text permanently you must put it in a @dfn{file}. Files are 306 things easier. But to keep any text permanently you must put it in a
241 named units of text which are stored by the operating system and which 307 @dfn{file}. Files are named units of text which are stored by the
242 you can retrieve by name. To look at or use the contents of a file in 308 operating system for you to retrieve later by name. To look at or use
243 any way, including editing the file with Emacs, you must specify the 309 the contents of a file in any way, including editing the file with
244 file name. 310 Emacs, you must specify the file name.
245 311
246 Consider a file named @file{/usr/rms/foo.c}. To begin editing 312 Consider a file named @file{/usr/rms/foo.c}. To begin editing
247 this file from Emacs, type: 313 this file from Emacs, type:
248 314
249 @example 315 @example
250 C-x C-f /usr/rms/foo.c @key{RET} 316 C-x C-f /usr/rms/foo.c @key{RET}
251 @end example 317 @end example
252 318
253 @noindent 319 @noindent
254 The file name is given as an @dfn{argument} to the command @kbd{C-x 320 Here the file name is given as an @dfn{argument} to the command @kbd{C-x
255 C-f} (@code{find-file}). The command uses the @dfn{minibuffer} to 321 C-f} (@code{find-file}). That command uses the @dfn{minibuffer} to
256 read the argument. You have to type @key{RET} to terminate the argument 322 read the argument, and you type @key{RET} to terminate the argument
257 (@pxref{Minibuffer}).@refill 323 (@pxref{Minibuffer}).
258 324
259 You can also use the @b{Open...} menu item from the @b{File} menu, then 325 You can also use the @b{Open...} menu item from the @b{File} menu, then
260 type the name of the file to the prompt. 326 type the name of the file to the prompt.
261 327
262 Emacs obeys the command by @dfn{visiting} the file: it creates a 328 Emacs obeys the command by @dfn{visiting} the file: creating a buffer,
263 buffer, copies the contents of the file into the buffer, and then 329 copying the contents of the file into the buffer, and then displaying
264 displays the buffer for you to edit. You can make changes in the 330 the buffer for you to edit. If you alter the text, you can @dfn{save}
265 buffer, and then @dfn{save} the file by typing @kbd{C-x C-s} 331 the new text in the file by typing @kbd{C-x C-s} (@code{save-buffer}) or
266 (@code{save-buffer}) or choosing @b{Save Buffer} from the @b{File} menu. 332 choosing @b{Save Buffer} from the @b{File} menu. This makes the changes
267 This makes the changes permanent by copying the altered contents of the 333 permanent by copying the altered buffer contents back into the file
268 buffer back into the file @file{/usr/rms/foo.c}. Until then, the 334 @file{/usr/rms/foo.c}. Until you save, the changes exist only inside
269 changes are only inside your Emacs buffer, and the file @file{foo.c} is 335 Emacs, and the file @file{foo.c} is unaltered.
270 not changed.@refill
271 336
272 To create a file, visit the file with @kbd{C-x C-f} as if it already 337 To create a file, visit the file with @kbd{C-x C-f} as if it already
273 existed or choose @b{Open...} from the @b{File} menu and provide the 338 existed or choose @b{Open...} from the @b{File} menu and provide the
274 name for the new file in the minibuffer. Emacs will create an empty 339 name for the new file. Emacs will create an empty buffer in which you
275 buffer in which you can insert the text you want to put in the file. 340 can insert the text you want to put in the file. When you save the
276 When you save the buffer with @kbd{C-x C-s}, or by choosing @b{Save 341 buffer with @kbd{C-x C-s}, or by choosing @b{Save Buffer} from the
277 Buffer} from the @b{File} menu, the file is created. 342 @b{File} menu, the file is created.
278 343
279 To learn more about using files, @pxref{Files}. 344 To learn more about using files, @xref{Files}.
280 345
346 @node Basic Help, Blank Lines, Basic Files, Basic
281 @section Help 347 @section Help
282 348
283 If you forget what a key does, you can use the Help character 349 @cindex getting help with keys
284 (@kbd{C-h}) to find out: Type @kbd{C-h k} followed by the key you want 350 If you forget what a key does, you can find out with the Help
285 to know about. For example, @kbd{C-h k C-n} tells you what @kbd{C-n} 351 character, which is @kbd{C-h} (or @key{F1}, which is an alias for
352 @kbd{C-h}). Type @kbd{C-h k} followed by the key you want to know
353 about; for example, @kbd{C-h k C-n} tells you all about what @kbd{C-n}
286 does. @kbd{C-h} is a prefix key; @kbd{C-h k} is just one of its 354 does. @kbd{C-h} is a prefix key; @kbd{C-h k} is just one of its
287 subcommands (the command @code{describe-key}). The other subcommands of 355 subcommands (the command @code{describe-key}). The other subcommands of
288 @kbd{C-h} provide different kinds of help. Type @kbd{C-h} three times 356 @kbd{C-h} provide different kinds of help. Type @kbd{C-h} twice to get
289 to get a description of all the help facilities. @xref{Help}.@refill 357 a description of all the help facilities. @xref{Help}.
290 358
291 @menu 359 @node Blank Lines, Continuation Lines, Basic Help, Basic
292 * Blank Lines:: Commands to make or delete blank lines.
293 * Continuation Lines:: Lines too wide for the frame.
294 * Position Info:: What page, line, row, or column is point on?
295 * Arguments:: Numeric arguments for repeating a command.
296 @end menu
297
298 @node Blank Lines, Continuation Lines, Basic, Basic
299 @section Blank Lines 360 @section Blank Lines
300 361
301 Here are special commands and techniques for entering and removing 362 @cindex inserting blank lines
363 @cindex deleting blank lines
364 Here are special commands and techniques for putting in and taking out
302 blank lines. 365 blank lines.
303 366
304 @c widecommands 367 @c widecommands
305 @table @kbd 368 @table @kbd
306 @item C-o 369 @item C-o
313 @kindex C-o 376 @kindex C-o
314 @kindex C-x C-o 377 @kindex C-x C-o
315 @cindex blank lines 378 @cindex blank lines
316 @findex open-line 379 @findex open-line
317 @findex delete-blank-lines 380 @findex delete-blank-lines
318 When you want to insert a new line of text before an existing line, 381 When you want to insert a new line of text before an existing line, you
319 you just type the new line of text, followed by @key{RET}. If you 382 can do it by typing the new line of text, followed by @key{RET}.
320 prefer to create a blank line first and then insert the desired text, 383 However, it may be easier to see what you are doing if you first make a
321 use the key @kbd{C-o} (@code{open-line}), which inserts a newline after 384 blank line and then insert the desired text into it. This is easy to do
322 point but leaves point in front of the newline. Then type 385 using the key @kbd{C-o} (@code{open-line}), which inserts a newline
323 the text into the new line. @kbd{C-o F O O} has the same effect as 386 after point but leaves point in front of the newline. After @kbd{C-o},
324 @kbd{F O O @key{RET}}, except for the final location of point. 387 type the text for the new line. @kbd{C-o F O O} has the same effect as
325 388 @w{@kbd{F O O @key{RET}}}, except for the final location of point.
326 To create several blank lines, type @kbd{C-o} several times, or 389
327 give @kbd{C-o} an argument indicating how many blank lines to create. 390 You can make several blank lines by typing @kbd{C-o} several times, or
328 @xref{Arguments}, for more information. 391 by giving it a numeric argument to tell it how many blank lines to make.
329 392 @xref{Arguments}, for how. If you have a fill prefix, then @kbd{C-o}
330 If you have many blank lines in a row and want to get rid of them, use 393 command inserts the fill prefix on the new line, when you use it at the
331 @kbd{C-x C-o} (@code{delete-blank-lines}). If point is on a blank 394 beginning of a line. @xref{Fill Prefix}.
332 line which is adjacent to at least one other blank line, @kbd{C-x C-o} 395
333 deletes all but one of the blank lines. 396 The easy way to get rid of extra blank lines is with the command
334 If point is on a blank line with no other adjacent blank line, the 397 @kbd{C-x C-o} (@code{delete-blank-lines}). @kbd{C-x C-o} in a run of
335 sole blank line is deleted. If point is on a non-blank 398 several blank lines deletes all but one of them. @kbd{C-x C-o} on a
336 line, @kbd{C-x C-o} deletes any blank lines following that non-blank 399 solitary blank line deletes that blank line. When point is on a
337 line. 400 nonblank line, @kbd{C-x C-o} deletes any blank lines following that
401 nonblank line.
338 402
339 @node Continuation Lines, Position Info, Blank Lines, Basic 403 @node Continuation Lines, Position Info, Blank Lines, Basic
340 @section Continuation Lines 404 @section Continuation Lines
341 405
342 @cindex continuation line 406 @cindex continuation line
343 If you add too many characters to one line without breaking with a 407 @cindex wrapping
344 @key{RET}, the line grows to occupy two (or more) screen lines, with a 408 @cindex line wrapping
345 curved arrow at the extreme right margin of all but the last line. The 409 If you add too many characters to one line without breaking it with
346 curved arrow indicates that the following screen line is not really a 410 @key{RET}, the line will grow to occupy two (or more) lines on the
347 distinct line in the text, but just the @dfn{continuation} of a line too 411 screen, with a curved arrow at the extreme right margin of all but the
348 long to fit the frame. You can use Auto Fill mode (@pxref{Filling}) 412 last of them. The curved arrow says that the following screen line is
349 to have Emacs insert newlines automatically when a line gets too long. 413 not really a distinct line in the text, but just the @dfn{continuation}
350 414 of a line too long to fit the screen. Continuation is also called
415 @dfn{line wrapping}.
416
417 Sometimes it is nice to have Emacs insert newlines automatically when
418 a line gets too long. Continuation on the screen does not do that. Use
419 Auto Fill mode (@pxref{Filling}) if that's what you want.
351 420
352 @vindex truncate-lines 421 @vindex truncate-lines
353 @cindex truncation 422 @cindex truncation
354 Instead of continuation, long lines can be displayed by @dfn{truncation}. 423 Instead of continuation, long lines can be displayed by @dfn{truncation}.
355 This means that all the characters that do not fit in the width of the 424 This means that all the characters that do not fit in the width of the
356 frame or window do not appear at all. They remain in the buffer, 425 frame or window do not appear at all. They remain in the buffer,
357 temporarily invisible. Three diagonal dots in the last column (instead of 426 temporarily invisible. Right arrow in the last column (instead of the
358 the curved arrow inform you that truncation is in effect. 427 curved arrow) inform you that truncation is in effect.
359 428
360 To turn off continuation for a particular buffer, set the 429 Truncation instead of continuation happens whenever horizontal
361 variable @code{truncate-lines} to non-@code{nil} in that buffer. 430 scrolling is in use, and optionally in all side-by-side windows
362 Truncation instead of continuation also happens whenever horizontal 431 (@pxref{Windows}). You can enable truncation for a particular buffer by
363 scrolling is in use, and optionally whenever side-by-side windows are in 432 setting the variable @code{truncate-lines} to non-@code{nil} in that
364 use (@pxref{Windows}). Altering the value of @code{truncate-lines} makes 433 buffer. (@xref{Variables}.) Altering the value of
365 it local to the current buffer; until that time, the default value is in 434 @code{truncate-lines} makes it local to the current buffer; until that
366 effect. The default is initially @code{nil}. @xref{Locals}.@refill 435 time, the default value is in effect. The default is initially
436 @code{nil}. @xref{Locals}.
437
438 @xref{Display Vars}, for additional variables that affect how text is
439 displayed.
367 440
368 @node Position Info, Arguments, Continuation Lines, Basic 441 @node Position Info, Arguments, Continuation Lines, Basic
369 @section Cursor Position Information 442 @section Cursor Position Information
370 443
371 If you are accustomed to other display editors, you may be surprised 444 If you are accustomed to other display editors, you may be surprised
378 @table @kbd 451 @table @kbd
379 @item M-x what-page 452 @item M-x what-page
380 Print page number of point, and line number within page. 453 Print page number of point, and line number within page.
381 @item M-x what-line 454 @item M-x what-line
382 Print line number of point in the buffer. 455 Print line number of point in the buffer.
456 @item M-x line-number-mode
457 Toggle automatic display of current line number.
383 @item M-= 458 @item M-=
384 Print number of lines and characters in the current region 459 Print number of lines and characters in the current region
385 (@code{count-lines-region}). 460 (@code{count-lines-region}). @xref{Mark}, for information about the
461 region.
386 @item C-x = 462 @item C-x =
387 Print character code of character after point, character position of 463 Print character code of character after point, character position of
388 point, and column of point (@code{what-cursor-position}). 464 point, and column of point (@code{what-cursor-position}).
389 @end table 465 @end table
390 466
394 @cindex page number 470 @cindex page number
395 @kindex M-= 471 @kindex M-=
396 @findex count-lines-region 472 @findex count-lines-region
397 473
398 There are several commands for printing line numbers: 474 There are several commands for printing line numbers:
475
399 @itemize @bullet 476 @itemize @bullet
400 @item 477 @item
401 @kbd{M-x what-line} counts lines from the beginning of the file and 478 @kbd{M-x what-line} counts lines from the beginning of the file and
402 prints the line number point is on. The first line of the file is line 479 prints the line number point is on. The first line of the file is line
403 number 1. You can use these numbers as arguments to @kbd{M-x 480 number 1. You can use these numbers as arguments to @kbd{M-x
405 @item 482 @item
406 @kbd{M-x what-page} counts pages from the beginning of the file, and 483 @kbd{M-x what-page} counts pages from the beginning of the file, and
407 counts lines within the page, printing both of them. @xref{Pages}, for 484 counts lines within the page, printing both of them. @xref{Pages}, for
408 the command @kbd{C-x l}, which counts the lines in the current page. 485 the command @kbd{C-x l}, which counts the lines in the current page.
409 @item 486 @item
410 @kbd{M-=} (@code{count-lines-region}) prints the number of lines in 487 @kbd{M-=} (@code{count-lines-region}) prints the number of lines in the
411 the region (@pxref{Mark}). 488 region (@pxref{Mark}). @xref{Pages}, for the command @kbd{C-x l} which
489 counts the lines in the
412 @end itemize 490 @end itemize
413 491
414 @kindex C-x = 492 @kindex C-x =
415 @findex what-cursor-position 493 @findex what-cursor-position
416 The command @kbd{C-x =} (@code{what-cursor-position}) provides 494 The command @kbd{C-x =} (@code{what-cursor-position}) can be used to find out
417 information about point and about the column the cursor is in. 495 the column that the cursor is in, and other miscellaneous information about
418 It prints a line in the echo area that looks like this: 496 point. It prints a line in the echo area that looks like this:
419 497
420 @example 498 @example
421 Char: x (0170) point=65986 of 563027(12%) column 44 499 Char: c (0143, 99, 0x63) point=18862 of 24800(76%) column 53
422 @end example 500 @end example
423 501
424 @noindent 502 @noindent
425 (In fact, this is the output produced when point is before @samp{column 44} 503 (In fact, this is the output produced when point is before @samp{column
426 in the example.) 504 53} in the example.)
427 505
428 The two values after @samp{Char:} describe the character following point, 506 The four values after @samp{Char:} describe the character that follows
429 first by showing it and second by giving its octal character code. 507 point, first by showing it and then by giving its character code in
508 octal, decimal and hex.
430 509
431 @samp{point=} is followed by the position of point expressed as a character 510 @samp{point=} is followed by the position of point expressed as a character
432 count. The front of the buffer counts as position 1, one character later 511 count. The front of the buffer counts as position 1, one character later
433 as 2, and so on. The next, larger number is the total number of characters 512 as 2, and so on. The next, larger number is the total number of characters
434 in the buffer. Afterward in parentheses comes the position expressed as a 513 in the buffer. Afterward in parentheses comes the position expressed as a
435 percentage of the total size. 514 percentage of the total size.
436 515
437 @samp{column} is followed by the horizontal position of point, in columns 516 @samp{column} is followed by the horizontal position of point, in
438 from the left edge of the window. 517 columns from the left edge of the window.
439 518
440 If the buffer has been narrowed, making some of the text at the 519 If the buffer has been narrowed, making some of the text at the
441 beginning and the end temporarily invisible, @kbd{C-x =} prints 520 beginning and the end temporarily invisible, @kbd{C-x =} prints
442 additional text describing the current visible range. For example, it 521 additional text describing the current visible range. For example, it
443 might say: 522 might say:
444 523
445 @smallexample 524 @smallexample
446 Char: x (0170) point=65986 of 563025(12%) <65102 - 68533> column 44 525 Char: c (0143, 99, 0x63) point=19674 of 24575(80%) <19591 - 19703> column 69
447 @end smallexample 526 @end smallexample
448 527
449 @noindent 528 @noindent
450 where the two extra numbers give the smallest and largest character position 529 where the two extra numbers give the smallest and largest character position
451 that point is allowed to assume. The characters between those two positions 530 that point is allowed to assume. The characters between those two positions
461 540
462 @node Arguments,, Position Info, Basic 541 @node Arguments,, Position Info, Basic
463 @section Numeric Arguments 542 @section Numeric Arguments
464 @cindex numeric arguments 543 @cindex numeric arguments
465 544
466 Any Emacs command can be given a @dfn{numeric argument}. Some commands 545 In mathematics and computer usage, the word @dfn{argument} means
467 interpret the argument as a repetition count. For example, giving an 546 ``data provided to a function or operation.'' Any Emacs command can be
468 argument of ten to the key @kbd{C-f} (the command @code{forward-char}, move 547 given a @dfn{numeric argument} (also called a @dfn{prefix argument}).
469 forward one character) moves forward ten characters. With these commands, 548 Some commands interpret the argument as a repetition count. For
470 no argument is equivalent to an argument of one. Negative arguments are 549 example, giving an argument of ten to the key @kbd{C-f} (the command
471 allowed. Often they tell a command to move or act backwards. 550 @code{forward-char}, move forward one character) moves forward ten
551 characters. With these commands, no argument is equivalent to an
552 argument of one. Negative arguments are allowed. Often they tell a
553 command to move or act in the opposite direction.
472 554
473 @kindex M-1 555 @kindex M-1
474 @kindex M-@t{-} 556 @kindex M-@t{-}
475 @findex digit-argument 557 @findex digit-argument
476 @findex negative-argument 558 @findex negative-argument
480 minus sign while holding down the @key{META} key. For example, 562 minus sign while holding down the @key{META} key. For example,
481 @example 563 @example
482 M-5 C-n 564 M-5 C-n
483 @end example 565 @end example
484 @noindent 566 @noindent
485 moves down five lines. The characters @kbd{Meta-1}, @kbd{Meta-2}, and 567 would move down five lines. The characters @kbd{Meta-1}, @kbd{Meta-2},
486 so on, as well as @kbd{Meta--}, do this because they are keys bound to 568 and so on, as well as @kbd{Meta--}, do this because they are keys bound
487 commands (@code{digit-argument} and @code{negative-argument}) that are 569 to commands (@code{digit-argument} and @code{negative-argument}) that
488 defined to contribute to an argument for the next command. 570 are defined to contribute to an argument for the next command. Digits
571 and @kbd{-} modified with Control, or Control and Meta, also specify
572 numeric arguments.
489 573
490 @kindex C-u 574 @kindex C-u
491 @findex universal-argument 575 @findex universal-argument
492 Another way of specifying an argument is to use the @kbd{C-u} 576 Another way of specifying an argument is to use the @kbd{C-u}
493 (@code{universal-argument}) command followed by the digits of the argument. 577 (@code{universal-argument}) command followed by the digits of the
494 With @kbd{C-u}, you can type the argument digits without holding 578 argument. With @kbd{C-u}, you can type the argument digits without
495 down shift keys. To type a negative argument, start with a minus sign. 579 holding down modifier keys; @kbd{C-u} works on all terminals. To type a
496 Just a minus sign normally means @minus{}1. @kbd{C-u} works on all terminals. 580 negative argument, type a minus sign after @kbd{C-u}. Just a minus sign
581 without digits normally means @minus{}1.
497 582
498 @kbd{C-u} followed by a character which is neither a digit nor a minus 583 @kbd{C-u} followed by a character which is neither a digit nor a minus
499 sign has the special meaning of ``multiply by four''. It multiplies the 584 sign has the special meaning of ``multiply by four''. It multiplies the
500 argument for the next command by four. @kbd{C-u} twice multiplies it by 585 argument for the next command by four. @kbd{C-u} twice multiplies it by
501 sixteen. Thus, @kbd{C-u C-u C-f} moves forward sixteen characters. This 586 sixteen. Thus, @kbd{C-u C-u C-f} moves forward sixteen characters. This
502 is a good way to move forward ``fast'', since it moves about 1/5 of a line 587 is a good way to move forward ``fast'', since it moves about 1/5 of a line
503 in the usual size frame. Other useful combinations are @kbd{C-u C-n}, 588 in the usual size frame. Other useful combinations are @kbd{C-u C-n},
504 @kbd{C-u C-u C-n} (move down a good fraction of a frame), @kbd{C-u C-u 589 @kbd{C-u C-u C-n} (move down a good fraction of a frame), @kbd{C-u C-u
505 C-o} (make ``a lot'' of blank lines), and @kbd{C-u C-k} (kill four 590 C-o} (make ``a lot'' of blank lines), and @kbd{C-u C-k} (kill four
506 lines).@refill 591 lines).
507 592
508 Some commands care only about whether there is an argument and not about 593 Some commands care only about whether there is an argument and not about
509 its value. For example, the command @kbd{M-q} (@code{fill-paragraph}) with 594 its value. For example, the command @kbd{M-q} (@code{fill-paragraph}) with
510 no argument fills text; with an argument, it justifies the text as well. 595 no argument fills text; with an argument, it justifies the text as well.
511 (@xref{Filling}, for more information on @kbd{M-q}.) Just @kbd{C-u} is a 596 (@xref{Filling}, for more information on @kbd{M-q}.) Just @kbd{C-u} is a
517 including their terminating newlines. But @kbd{C-k} with no argument is 602 including their terminating newlines. But @kbd{C-k} with no argument is
518 special: it kills the text up to the next newline, or, if point is right at 603 special: it kills the text up to the next newline, or, if point is right at
519 the end of the line, it kills the newline itself. Thus, two @kbd{C-k} 604 the end of the line, it kills the newline itself. Thus, two @kbd{C-k}
520 commands with no arguments can kill a non-blank line, just like @kbd{C-k} 605 commands with no arguments can kill a non-blank line, just like @kbd{C-k}
521 with an argument of one. (@xref{Killing}, for more information on 606 with an argument of one. (@xref{Killing}, for more information on
522 @kbd{C-k}.)@refill 607 @kbd{C-k}.)
523 608
524 A few commands treat a plain @kbd{C-u} differently from an ordinary 609 A few commands treat a plain @kbd{C-u} differently from an ordinary
525 argument. A few others may treat an argument of just a minus sign 610 argument. A few others may treat an argument of just a minus sign
526 differently from an argument of @minus{}1. These unusual cases will be 611 differently from an argument of @minus{}1. These unusual cases are
527 described when they come up; they are always to make the individual 612 described when they come up; they are always for reasons of convenience
528 command more convenient to use. 613 of use of the individual command.
529 614
530 @c section Autoarg Mode 615 You can use a numeric argument to insert multiple copies of a
616 character. This is straightforward unless the character is a digit; for
617 example, @kbd{C-u 6 4 a} inserts 64 copies of the character @samp{a}.
618 But this does not work for inserting digits; @kbd{C-u 6 4 1} specifies
619 an argument of 641, rather than inserting anything. To separate the
620 digit to insert from the argument, type another @kbd{C-u}; for example,
621 @kbd{C-u 6 4 C-u 1} does insert 64 copies of the character @samp{1}.
622
623 We use the term ``prefix argument'' as well as ``numeric argument'' to
624 emphasize that you type the argument before the command, and to
625 distinguish these arguments from minibuffer arguments that come after
626 the command.
627
531 @ignore 628 @ignore
532 @cindex autoarg mode 629 @node Repeating
533 Users of ASCII keyboards may prefer to use Autoarg mode. Autoarg mode 630 @section Repeating a Command
534 means that you don't need to type @kbd{C-u} to specify a numeric argument. 631 @cindex repeating a command
535 Instead, you type just the digits. Digits followed by an ordinary 632
536 inserting character are themselves inserted, but digits followed by an 633 @kindex C-x z
537 Escape or Control character serve as an argument to it and are not 634 @findex repeat
538 inserted. A minus sign can also be part of an argument, but only at the 635 The command @kbd{C-x z} (@code{repeat}) provides another way to repeat
539 beginning. If you type a minus sign following some digits, both the digits 636 an Emacs command many times. This command repeats the previous Emacs
540 and the minus sign are inserted. 637 command, whatever that was. Repeating a command uses the same arguments
541 638 that were used before; it does not read new arguments each time.
542 To use Autoarg mode, set the variable Autoarg Mode nonzero. 639
543 @xref{Variables}. 640 To repeat the command more than once, type additional @kbd{z}'s: each
544 641 @kbd{z} repeats the command one more time. Repetition ends when you
545 Autoargument digits echo at the bottom of the frame; the first 642 type a character other than @kbd{z}, or press a mouse button.
546 nondigit causes them to be inserted or uses them as an argument. To 643
547 insert some digits and nothing else, you must follow them with a Space 644 For example, suppose you type @kbd{C-u 2 0 C-d} to delete 20
548 and then rub it out. @kbd{C-g} cancels the digits, while Delete inserts 645 characters. You can repeat that command (including its argument) three
549 them all and then rubs out the last. 646 additional times, to delete a total of 80 characters, by typing @kbd{C-x
647 z z z}. The first @kbd{C-x z} repeats the command once, and each
648 subsequent @kbd{z} repeats it once again.
649
550 @end ignore 650 @end ignore