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