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2 @node Glossary, Manifesto, Intro, Top | |
3 @unnumbered Glossary | |
4 | |
5 @table @asis | |
6 @item Abbrev | |
7 An abbrev is a text string which expands into a different text string | |
8 when present in the buffer. For example, you might define a short | |
9 word as an abbrev for a long phrase that you want to insert | |
10 frequently. @xref{Abbrevs}. | |
11 | |
12 @item Aborting | |
13 Aborting means getting out of a recursive edit (q.v.@:). You can use | |
14 the commands @kbd{C-]} and @kbd{M-x top-level} for this. | |
15 @xref{Quitting}. | |
16 | |
17 @item Auto Fill mode | |
18 Auto Fill mode is a minor mode in which text you insert is | |
19 automatically broken into lines of fixed width. @xref{Filling}. | |
20 | |
21 @item Auto Saving | |
22 Auto saving means that Emacs automatically stores the contents of an | |
23 Emacs buffer in a specially-named file so the information will not be | |
24 lost if the buffer is lost due to a system error or user error. | |
25 @xref{Auto Save}. | |
26 | |
27 @item Backup File | |
28 A backup file records the contents that a file had before the current | |
29 editing session. Emacs creates backup files automatically to help you | |
30 track down or cancel changes you later regret. @xref{Backup}. | |
31 | |
32 @item Balance Parentheses | |
33 Emacs can balance parentheses manually or automatically. Manual | |
34 balancing is done by the commands to move over balanced expressions | |
35 (@pxref{Lists}). Automatic balancing is done by blinking the | |
36 parenthesis that matches one just inserted (@pxref{Matching,,Matching | |
37 Parens}). | |
38 | |
39 @item Bind | |
40 To bind a key is to change its binding (q.v.@:). @xref{Rebinding}. | |
41 | |
42 @item Binding | |
43 A key gets its meaning in Emacs by having a binding which is a | |
44 command (q.v.@:), a Lisp function that is run when the key is typed. | |
45 @xref{Commands,Binding}. Customization often involves rebinding a | |
46 character to a different command function. The bindings of all keys | |
47 are recorded in the keymaps (q.v.@:). @xref{Keymaps}. | |
48 | |
49 @item Blank Lines | |
50 Blank lines are lines that contain only whitespace. Emacs has several | |
51 commands for operating on the blank lines in a buffer. | |
52 | |
53 @item Buffer | |
54 The buffer is the basic editing unit; one buffer corresponds to one | |
55 piece of text being edited. You can have several buffers, but at any | |
56 time you are editing only one, the `selected' buffer, though several | |
57 buffers can be visible when you are using multiple windows. @xref{Buffers}. | |
58 | |
59 @item Buffer Selection History | |
60 Emacs keeps a buffer selection history which records how recently each | |
61 Emacs buffer was selected. Emacs uses this list when choosing a buffer to | |
62 select. @xref{Buffers}. | |
63 | |
64 @item C- | |
65 @samp{C} in the name of a character is an abbreviation for Control. | |
66 @xref{Keystrokes,C-}. | |
67 | |
68 @item C-M- | |
69 @samp{C-M-} in the name of a character is an abbreviation for | |
70 Control-Meta. @xref{Keystrokes,C-M-}. | |
71 | |
72 @item Case Conversion | |
73 Case conversion means changing text from upper case to lower case or | |
74 vice versa. @xref{Case}, for the commands for case conversion. | |
75 | |
76 @item Characters | |
77 Characters form the contents of an Emacs buffer; also, Emacs commands | |
78 are invoked by keys (q.v.@:), which are sequences of one or more | |
79 characters. @xref{Keystrokes}. | |
80 | |
81 @item Command | |
82 A command is a Lisp function specially defined to be able to serve as a | |
83 key binding in Emacs. When you type a key (q.v.@:), Emacs looks up its | |
84 binding (q.v.@:) in the relevant keymaps (q.v.@:) to find the command to | |
85 run. @xref{Commands}. | |
86 | |
87 @item Command Name | |
88 A command name is the name of a Lisp symbol which is a command | |
89 (@pxref{Commands}). You can invoke any command by its name using | |
90 @kbd{M-x} (@pxref{M-x}). | |
91 | |
92 @item Comments | |
93 A comment is text in a program which is intended only for the people | |
94 reading the program, and is marked specially so that it will be | |
95 ignored when the program is loaded or compiled. Emacs offers special | |
96 commands for creating, aligning, and killing comments. | |
97 @xref{Comments}. | |
98 | |
99 @item Compilation | |
100 Compilation is the process of creating an executable program from | |
101 source code. Emacs has commands for compiling files of Emacs Lisp | |
102 code (@pxref{Lisp Libraries}) and programs in C and other languages | |
103 (@pxref{Compilation}). | |
104 | |
105 @item Complete Key | |
106 A complete key is a character or sequence of characters which, when typed | |
107 by the user, fully specifies one action to be performed by Emacs. For | |
108 example, @kbd{X} and @kbd{Control-f} and @kbd{Control-x m} are keys. Keys | |
109 derive their meanings from being bound (q.v.@:) to commands (q.v.@:). | |
110 Thus, @kbd{X} is conventionally bound to a command to insert @samp{X} in | |
111 the buffer; @kbd{C-x m} is conventionally bound to a command to begin | |
112 composing a mail message. @xref{Keystrokes}. | |
113 | |
114 @item Completion | |
115 When Emacs automatically fills an abbreviation for a name into the | |
116 entire name, that process is called completion. Completion is done for | |
117 minibuffer (q.v.@:) arguments when the set of possible valid inputs is | |
118 known; for example, on command names, buffer names, and file names. | |
119 Completion occurs when you type @key{TAB}, @key{SPC}, or @key{RET}. | |
120 @xref{Completion}.@refill | |
121 | |
122 @item Continuation Line | |
123 When a line of text is longer than the width of the frame, it | |
124 takes up more than one screen line when displayed. We say that the | |
125 text line is continued, and all screen lines used for it after the | |
126 first are called continuation lines. @xref{Basic,Continuation,Basic | |
127 Editing}. | |
128 | |
129 @item Control-Character | |
130 ASCII characters with octal codes 0 through 037, and also code 0177, | |
131 do not have graphic images assigned to them. These are the control | |
132 characters. Any control character can be typed by holding down the | |
133 @key{CTRL} key and typing some other character; some have special keys | |
134 on the keyboard. @key{RET}, @key{TAB}, @key{ESC}, @key{LFD}, and | |
135 @key{DEL} are all control characters. @xref{Keystrokes}.@refill | |
136 | |
137 @item Copyleft | |
138 A copyleft is a notice giving the public legal permission to redistribute | |
139 a program or other work of art. Copylefts are used by leftists to enrich | |
140 the public just as copyrights are used by rightists to gain power over | |
141 the public. | |
142 | |
143 @item Current Buffer | |
144 The current buffer in Emacs is the Emacs buffer on which most editing | |
145 commands operate. You can select any Emacs buffer as the current one. | |
146 @xref{Buffers}. | |
147 | |
148 @item Current Line | |
149 The line point is on (@pxref{Point}). | |
150 | |
151 @item Current Paragraph | |
152 The paragraph that point is in. If point is between paragraphs, the | |
153 current paragraph is the one that follows point. @xref{Paragraphs}. | |
154 | |
155 @item Current Defun | |
156 The defun (q.v.@:) that point is in. If point is between defuns, the | |
157 current defun is the one that follows point. @xref{Defuns}. | |
158 | |
159 @item Cursor | |
160 The cursor is the rectangle on the screen which indicates the position | |
161 called point (q.v.@:) at which insertion and deletion takes place. | |
162 The cursor is on or under the character that follows point. Often | |
163 people speak of `the cursor' when, strictly speaking, they mean | |
164 `point'. @xref{Basic,Cursor,Basic Editing}. | |
165 | |
166 @item Customization | |
167 Customization is making minor changes in the way Emacs works. It is | |
168 often done by setting variables (@pxref{Variables}) or by rebinding | |
169 keys (@pxref{Keymaps}). | |
170 | |
171 @item Default Argument | |
172 The default for an argument is the value that is used if you do not | |
173 specify one. When Emacs prompts you in the minibuffer for an argument, | |
174 the default argument is used if you just type @key{RET}. | |
175 @xref{Minibuffer}. | |
176 | |
177 @item Default Directory | |
178 When you specify a file name that does not start with @samp{/} or @samp{~}, | |
179 it is interpreted relative to the current buffer's default directory. | |
180 @xref{Minibuffer File,Default Directory}. | |
181 | |
182 @item Defun | |
183 A defun is a list at the top level of parenthesis or bracket structure | |
184 in a program. It is so named because most such lists in Lisp programs | |
185 are calls to the Lisp function @code{defun}. @xref{Defuns}. | |
186 | |
187 @item @key{DEL} | |
188 The @key{DEL} character runs the command that deletes one character of | |
189 text. @xref{Basic,DEL,Basic Editing}. | |
190 | |
191 @item Deletion | |
192 Deleting text means erasing it without saving it. Emacs deletes text | |
193 only when it is expected not to be worth saving (all whitespace, or | |
194 only one character). The alternative is killing (q.v.@:). | |
195 @xref{Killing,Deletion}. | |
196 | |
197 @item Deletion of Files | |
198 Deleting a file means removing it from the file system. | |
199 @xref{Misc File Ops}. | |
200 | |
201 @item Deletion of Messages | |
202 Deleting a message means flagging it to be eliminated from your mail | |
203 file. Until the mail file is expunged, you can undo this by undeleting | |
204 the message. | |
205 | |
206 @item Deletion of Frames | |
207 When working under the multi-frame X-based version of XEmacs, | |
208 you can delete individual frames using the @b{Close} menu item from the | |
209 @b{File} menu. | |
210 | |
211 @item Deletion of Windows | |
212 When you delete a subwindow of an Emacs frame, you eliminate it from | |
213 the frame. Other windows expand to use up the space. The deleted | |
214 window can never come back, but no actual text is lost. @xref{Windows}. | |
215 | |
216 @item Directory | |
217 Files in the Unix file system are grouped into file directories. | |
218 @xref{ListDir,,Directories}. | |
219 | |
220 @item Dired | |
221 Dired is the Emacs facility that displays the contents of a file | |
222 directory and allows you to ``edit the directory'', performing | |
223 operations on the files in the directory. @xref{Dired}. | |
224 | |
225 @item Disabled Command | |
226 A disabled command is one that you may not run without special | |
227 confirmation. Commands are usually disabled because they are | |
228 confusing for beginning users. @xref{Disabling}. | |
229 | |
230 @item Dribble File | |
231 A file into which Emacs writes all the characters that the user types | |
232 on the keyboard. Dribble files are used to make a record for | |
233 debugging Emacs bugs. Emacs does not make a dribble file unless you | |
234 tell it to. @xref{Bugs}. | |
235 | |
236 @item Echo Area | |
237 The area at the bottom of the Emacs frame which is used for echoing the | |
238 arguments to commands, for asking questions, and for printing brief | |
239 messages (including error messages). @xref{Echo Area}. | |
240 | |
241 @item Echoing | |
242 Echoing refers to acknowledging the receipt of commands by displaying them | |
243 (in the echo area). Emacs never echoes single-character keys; longer | |
244 keys echo only if you pause while typing them. | |
245 | |
246 @item Error | |
247 An error occurs when an Emacs command cannot execute in the current | |
248 circumstances. When an error occurs, execution of the command stops | |
249 (unless the command has been programmed to do otherwise) and Emacs | |
250 reports the error by printing an error message (q.v.). Type-ahead | |
251 is discarded. Then Emacs is ready to read another editing command. | |
252 | |
253 @item Error Messages | |
254 Error messages are single lines of output printed by Emacs when the | |
255 user asks for something impossible to do (such as killing text | |
256 forward when point is at the end of the buffer). They appear in the | |
257 echo area, accompanied by a beep. | |
258 | |
259 @item @key{ESC} | |
260 @key{ESC} is a character used as a prefix for typing Meta characters on | |
261 keyboards lacking a @key{META} key. Unlike the @key{META} key (which, | |
262 like the @key{SHIFT} key, is held down while another character is | |
263 typed), the @key{ESC} key is pressed and released, and applies to the | |
264 next character typed. | |
265 | |
266 @item Fill Prefix | |
267 The fill prefix is a string that Emacs enters at the beginning | |
268 of each line when it performs filling. It is not regarded as part of the | |
269 text to be filled. @xref{Filling}. | |
270 | |
271 @item Filling | |
272 Filling text means moving text from line to line so that all the lines | |
273 are approximately the same length. @xref{Filling}. | |
274 | |
275 @item Frame | |
276 When running Emacs on a TTY terminal, ``frame'' means the terminal's | |
277 screen. When running Emacs under X, you can have multiple frames, | |
278 each corresponding to a top-level X window and each looking like | |
279 the screen on a TTY. Each frame contains one or more non-overlapping | |
280 Emacs windows (possibly with associated scrollbars, under X), an | |
281 echo area, and (under X) possibly a menubar. | |
282 | |
283 @item Global | |
284 Global means `independent of the current environment; in effect | |
285 @*throughout Emacs'. It is the opposite of local (q.v.@:). | |
286 Examples of the use of `global' appear below. | |
287 | |
288 @item Global Abbrev | |
289 A global definition of an abbrev (q.v.@:) is effective in all major | |
290 modes that do not have local (q.v.@:) definitions for the same abbrev. | |
291 @xref{Abbrevs}. | |
292 | |
293 @item Global Keymap | |
294 The global keymap (q.v.@:) contains key bindings that are in effect | |
295 unless local key bindings in a major mode's local | |
296 keymap (q.v.@:) override them.@xref{Keymaps}. | |
297 | |
298 @item Global Substitution | |
299 Global substitution means replacing each occurrence of one string by | |
300 another string through a large amount of text. @xref{Replace}. | |
301 | |
302 @item Global Variable | |
303 The global value of a variable (q.v.@:) takes effect in all buffers | |
304 that do not have their own local (q.v.@:) values for the variable. | |
305 @xref{Variables}. | |
306 | |
307 @item Graphic Character | |
308 Graphic characters are those assigned pictorial images rather than | |
309 just names. All the non-Meta (q.v.@:) characters except for the | |
310 Control (q.v.@:) character are graphic characters. These include | |
311 letters, digits, punctuation, and spaces; they do not include | |
312 @key{RET} or @key{ESC}. In Emacs, typing a graphic character inserts | |
313 that character (in ordinary editing modes). @xref{Basic,,Basic Editing}. | |
314 | |
315 @item Grinding | |
316 Grinding means adjusting the indentation in a program to fit the | |
317 nesting structure. @xref{Indentation,Grinding}. | |
318 | |
319 @item Hardcopy | |
320 Hardcopy means printed output. Emacs has commands for making printed | |
321 listings of text in Emacs buffers. @xref{Hardcopy}. | |
322 | |
323 @item @key{HELP} | |
324 You can type @key{HELP} at any time to ask what options you have, or | |
325 to ask what any command does. @key{HELP} is really @kbd{Control-h}. | |
326 @xref{Help}. | |
327 | |
328 @item Inbox | |
329 An inbox is a file in which mail is delivered by the operating system. | |
330 Some mail handlers transfers mail from inboxes to mail files (q.v.) in | |
331 which the mail is then stored permanently or until explicitly deleted. | |
332 | |
333 @item Indentation | |
334 Indentation means blank space at the beginning of a line. Most | |
335 programming languages have conventions for using indentation to | |
336 illuminate the structure of the program, and Emacs has special | |
337 features to help you set up the correct indentation. | |
338 @xref{Indentation}. | |
339 | |
340 @item Insertion | |
341 Insertion means copying text into the buffer, either from the keyboard | |
342 or from some other place in Emacs. | |
343 | |
344 @item Justification | |
345 Justification means adding extra spaces to lines of text to make them | |
346 come exactly to a specified width. @xref{Filling,Justification}. | |
347 | |
348 @item Keyboard Macros | |
349 Keyboard macros are a way of defining new Emacs commands from | |
350 sequences of existing ones, with no need to write a Lisp program. | |
351 @xref{Keyboard Macros}. | |
352 | |
353 @item Key | |
354 A key is a sequence of characters that, when input to Emacs, specify | |
355 or begin to specify a single action for Emacs to perform. That is, | |
356 the sequence is considered a single unit. If the key is enough to | |
357 specify one action, it is a complete key (q.v.); if it is less than | |
358 enough, it is a prefix key (q.v.). @xref{Keystrokes}. | |
359 | |
360 @item Keymap | |
361 The keymap is the data structure that records the bindings (q.v.@:) of | |
362 keys to the commands that they run. For example, the keymap binds the | |
363 character @kbd{C-n} to the command function @code{next-line}. | |
364 @xref{Keymaps}. | |
365 | |
366 @item Kill Ring | |
367 The kill ring is the place where all text you have killed recently is saved. | |
368 You can re-insert any of the killed text still in the ring; this is | |
369 called yanking (q.v.@:). @xref{Yanking}. | |
370 | |
371 @item Killing | |
372 Killing means erasing text and saving it on the kill ring so it can be | |
373 yanked (q.v.@:) later. Some other systems call this ``cutting.'' | |
374 Most Emacs commands to erase text do killing, as opposed to deletion | |
375 (q.v.@:). @xref{Killing}. | |
376 | |
377 @item Killing Jobs | |
378 Killing a job (such as, an invocation of Emacs) means making it cease | |
379 to exist. Any data within it, if not saved in a file, is lost. | |
380 @xref{Exiting}. | |
381 | |
382 @item List | |
383 A list is, approximately, a text string beginning with an open | |
384 parenthesis and ending with the matching close parenthesis. In C mode | |
385 and other non-Lisp modes, groupings surrounded by other kinds of matched | |
386 delimiters appropriate to the language, such as braces, are also | |
387 considered lists. Emacs has special commands for many operations on | |
388 lists. @xref{Lists}. | |
389 | |
390 @item Local | |
391 Local means `in effect only in a particular context'; the relevant | |
392 kind of context is a particular function execution, a particular | |
393 buffer, or a particular major mode. Local is the opposite of `global' | |
394 (q.v.@:). Specific uses of `local' in Emacs terminology appear below. | |
395 | |
396 @item Local Abbrev | |
397 A local abbrev definition is effective only if a particular major mode | |
398 is selected. In that major mode, it overrides any global definition | |
399 for the same abbrev. @xref{Abbrevs}. | |
400 | |
401 @item Local Keymap | |
402 A local keymap is used in a particular major mode; the key bindings | |
403 (q.v.@:) in the current local keymap override global bindings of the | |
404 same keys. @xref{Keymaps}. | |
405 | |
406 @item Local Variable | |
407 A local value of a variable (q.v.@:) applies to only one buffer. | |
408 @xref{Locals}. | |
409 | |
410 @item M- | |
411 @kbd{M-} in the name of a character is an abbreviation for @key{META}, | |
412 one of the modifier keys that can accompany any character. | |
413 @xref{Keystrokes}. | |
414 | |
415 @item M-C- | |
416 @samp{M-C-} in the name of a character is an abbreviation for | |
417 Control-Meta; it means the same thing as @samp{C-M-}. If your | |
418 terminal lacks a real @key{META} key, you type a Control-Meta character by | |
419 typing @key{ESC} and then typing the corresponding Control character. | |
420 @xref{Keystrokes,C-M-}. | |
421 | |
422 @item M-x | |
423 @kbd{M-x} is the key which is used to call an Emacs command by name. | |
424 You use it to call commands that are not bound to keys. | |
425 @xref{M-x}. | |
426 | |
427 @item Mail | |
428 Mail means messages sent from one user to another through the computer | |
429 system, to be read at the recipient's convenience. Emacs has commands for | |
430 composing and sending mail, and for reading and editing the mail you have | |
431 received. @xref{Sending Mail}. | |
432 | |
433 @item Major Mode | |
434 The major modes are a mutually exclusive set of options each of which | |
435 configures Emacs for editing a certain sort of text. Ideally, each | |
436 programming language has its own major mode. @xref{Major Modes}. | |
437 | |
438 @item Mark | |
439 The mark points to a position in the text. It specifies one end of the | |
440 region (q.v.@:), point being the other end. Many commands operate on | |
441 the whole region, that is, all the text from point to the mark. | |
442 @xref{Mark}. | |
443 | |
444 @item Mark Ring | |
445 The mark ring is used to hold several recent previous locations of the | |
446 mark, just in case you want to move back to them. @xref{Mark Ring}. | |
447 | |
448 @item Message | |
449 See `mail'. | |
450 | |
451 @item Meta | |
452 Meta is the name of a modifier bit which a command character may have. | |
453 It is present in a character if the character is typed with the | |
454 @key{META} key held down. Such characters are given names that start | |
455 with @kbd{Meta-}. For example, @kbd{Meta-<} is typed by holding down | |
456 @key{META} and at the same time typing @kbd{<} (which itself is done, | |
457 on most terminals, by holding down @key{SHIFT} and typing @kbd{,}). | |
458 @xref{Keystrokes,Meta}. | |
459 | |
460 @item Meta Character | |
461 A Meta character is one whose character code includes the Meta bit. | |
462 | |
463 @item Minibuffer | |
464 The minibuffer is the window that Emacs displays inside the | |
465 echo area (q.v.@:) when it prompts you for arguments to commands. | |
466 @xref{Minibuffer}. | |
467 | |
468 @item Minor Mode | |
469 A minor mode is an optional feature of Emacs which can be switched on | |
470 or off independent of the major mode. Each minor mode has a | |
471 command to turn it on or off. @xref{Minor Modes}. | |
472 | |
473 @item Mode Line | |
474 The mode line is the line at the bottom of each text window (q.v.@:), | |
475 which gives status information on the buffer displayed in that window. | |
476 @xref{Mode Line}. | |
477 | |
478 @item Modified Buffer | |
479 A buffer (q.v.@:) is modified if its text has been changed since the | |
480 last time the buffer was saved (or since it was created, if it | |
481 has never been saved). @xref{Saving}. | |
482 | |
483 @item Moving Text | |
484 Moving text means erasing it from one place and inserting it in | |
485 another. This is done by killing (q.v.@:) and then yanking (q.v.@:). | |
486 @xref{Killing}. | |
487 | |
488 @item Named Mark | |
489 A named mark is a register (q.v.@:) in its role of recording a | |
490 location in text so that you can move point to that location. | |
491 @xref{Registers}. | |
492 | |
493 @item Narrowing | |
494 Narrowing means creating a restriction (q.v.@:) that limits editing in | |
495 the current buffer to only a part of the text in the buffer. Text | |
496 outside that part is inaccessible to the user until the boundaries are | |
497 widened again, but it is still there, and saving the file saves the | |
498 invisible text. @xref{Narrowing}. | |
499 | |
500 @item Newline | |
501 @key{LFD} characters in the buffer terminate lines of text and are | |
502 called newlines. @xref{Keystrokes,Newline}. | |
503 | |
504 @item Numeric Argument | |
505 A numeric argument is a number, specified before a command, to change | |
506 the effect of the command. Often the numeric argument serves as a | |
507 repeat count. @xref{Arguments}. | |
508 | |
509 @item Option | |
510 An option is a variable (q.v.@:) that allows you to customize | |
511 Emacs by giving it a new value. @xref{Variables}. | |
512 | |
513 @item Overwrite Mode | |
514 Overwrite mode is a minor mode. When it is enabled, ordinary text | |
515 characters replace the existing text after point rather than pushing | |
516 it to the right. @xref{Minor Modes}. | |
517 | |
518 @item Page | |
519 A page is a unit of text, delimited by formfeed characters (ASCII | |
520 Control-L, code 014) coming at the beginning of a line. Some Emacs | |
521 commands are provided for moving over and operating on pages. | |
522 @xref{Pages}. | |
523 | |
524 @item Paragraphs | |
525 Paragraphs are the medium-size unit of English text. There are | |
526 special Emacs commands for moving over and operating on paragraphs. | |
527 @xref{Paragraphs}. | |
528 | |
529 @item Parsing | |
530 We say that Emacs parses words or expressions in the text being | |
531 edited. Really, all it knows how to do is find the other end of a | |
532 word or expression. @xref{Syntax}. | |
533 | |
534 @item Point | |
535 Point is the place in the buffer at which insertion and deletion | |
536 occur. Point is considered to be between two characters, not at one | |
537 character. The terminal's cursor (q.v.@:) indicates the location of | |
538 point. @xref{Basic,Point}. | |
539 | |
540 @item Prefix Key | |
541 A prefix key is a key (q.v.@:) whose sole function is to introduce a | |
542 set of multi-character keys. @kbd{Control-x} is an example of a prefix | |
543 key; any two-character sequence starting with @kbd{C-x} is also | |
544 a legitimate key. @xref{Keystrokes}. | |
545 | |
546 @item Prompt | |
547 A prompt is text printed to ask the user for input. Printing a prompt | |
548 is called prompting. Emacs prompts always appear in the echo area | |
549 (q.v.@:). One kind of prompting happens when the minibuffer is used | |
550 to read an argument (@pxref{Minibuffer}); the echoing which happens | |
551 when you pause in the middle of typing a multi-character key is also a | |
552 kind of prompting (@pxref{Echo Area}). | |
553 | |
554 @item Quitting | |
555 Quitting means cancelling a partially typed command or a running | |
556 command, using @kbd{C-g}. @xref{Quitting}. | |
557 | |
558 @item Quoting | |
559 Quoting means depriving a character of its usual special significance. | |
560 In Emacs this is usually done with @kbd{Control-q}. What constitutes special | |
561 significance depends on the context and on convention. For example, | |
562 an ``ordinary'' character as an Emacs command inserts itself; so in | |
563 this context, a special character is any character that does not | |
564 normally insert itself (such as @key{DEL}, for example), and quoting | |
565 it makes it insert itself as if it were not special. Not all contexts | |
566 allow quoting. @xref{Basic,Quoting,Basic Editing}. | |
567 | |
568 @item Read-only Buffer | |
569 A read-only buffer is one whose text you are not allowed to change. | |
570 Normally Emacs makes buffers read-only when they contain text which | |
571 has a special significance to Emacs, such asDired buffers. | |
572 Visiting a file that is write-protected also makes a read-only buffer. | |
573 @xref{Buffers}. | |
574 | |
575 @item Recursive Editing Level | |
576 A recursive editing level is a state in which part of the execution of | |
577 a command involves asking the user to edit some text. This text may | |
578 or may not be the same as the text to which the command was applied. | |
579 The mode line indicates recursive editing levels with square brackets | |
580 (@samp{[} and @samp{]}). @xref{Recursive Edit}. | |
581 | |
582 @item Redisplay | |
583 Redisplay is the process of correcting the image on the screen to | |
584 correspond to changes that have been made in the text being edited. | |
585 @xref{Frame,Redisplay}. | |
586 | |
587 @item Regexp | |
588 See `regular expression'. | |
589 | |
590 @item Region | |
591 The region is the text between point (q.v.@:) and the mark (q.v.@:). | |
592 Many commands operate on the text of the region. @xref{Mark,Region}. | |
593 | |
594 @item Registers | |
595 Registers are named slots in which text or buffer positions or | |
596 rectangles can be saved for later use. @xref{Registers}. | |
597 | |
598 @item Regular Expression | |
599 A regular expression is a pattern that can match various text strings; | |
600 for example, @samp{l[0-9]+} matches @samp{l} followed by one or more | |
601 digits. @xref{Regexps}. | |
602 | |
603 @item Replacement | |
604 See `global substitution'. | |
605 | |
606 @item Restriction | |
607 A buffer's restriction is the amount of text, at the beginning or the | |
608 end of the buffer, that is temporarily invisible and inaccessible. | |
609 Giving a buffer a nonzero amount of restriction is called narrowing | |
610 (q.v.). @xref{Narrowing}. | |
611 | |
612 @item @key{RET} | |
613 @key{RET} is the character than runs the command to insert a | |
614 newline into the text. It is also used to terminate most arguments | |
615 read in the minibuffer (q.v.@:). @xref{Keystrokes,Return}. | |
616 | |
617 @item Saving | |
618 Saving a buffer means copying its text into the file that was visited | |
619 (q.v.@:) in that buffer. To actually change a file you have edited in | |
620 Emacs, you have to save it. @xref{Saving}. | |
621 | |
622 @item Scrolling | |
623 Scrolling means shifting the text in the Emacs window to make a | |
624 different part ot the buffer visible. @xref{Display,Scrolling}. | |
625 | |
626 @item Searching | |
627 Searching means moving point to the next occurrence of a specified | |
628 string. @xref{Search}. | |
629 | |
630 @item Selecting | |
631 Selecting a buffer means making it the current (q.v.@:) buffer. | |
632 @xref{Buffers,Selecting}. | |
633 | |
634 @item Self-documentation | |
635 Self-documentation is the feature of Emacs which can tell you what any | |
636 command does, or can give you a list of all commands related to a topic | |
637 you specify. You ask for self-documentation with the help character, | |
638 @kbd{C-h}. @xref{Help}. | |
639 | |
640 @item Sentences | |
641 Emacs has commands for moving by or killing by sentences. | |
642 @xref{Sentences}. | |
643 | |
644 @item Sexp | |
645 An sexp (short for `s-expression,' itself short for `symbolic | |
646 expression') is the basic syntactic unit of Lisp | |
647 in its textual form: either a list, or Lisp atom. Many Emacs commands | |
648 operate on sexps. The term `sexp' is generalized to languages other | |
649 than Lisp to mean a syntactically recognizable expression. | |
650 @xref{Lists,Sexps}. | |
651 | |
652 @item Simultaneous Editing | |
653 Simultaneous editing means two users modifying the same file at once. | |
654 If simultaneous editing is not detected, you may lose your | |
655 work. Emacs detects all cases of simultaneous editing and warns the | |
656 user to investigate them. @xref{Interlocking,,Simultaneous Editing}. | |
657 | |
658 @item String | |
659 A string is a kind of Lisp data object which contains a sequence of | |
660 characters. Many Emacs variables are intended to have strings as | |
661 values. The Lisp syntax for a string consists of the characters in | |
662 the string with a @samp{"} before and another @samp{"} after. Write a | |
663 @samp{"} that is part of the string as @samp{\"} and a | |
664 @samp{\} that is part of the string as @samp{\\}. You can include all | |
665 other characters, including newline, just by writing | |
666 them inside the string. You can also include escape sequences as in C, such as | |
667 @samp{\n} for newline or @samp{\241} using an octal character code. | |
668 | |
669 @item String Substitution | |
670 See `global substitution'. | |
671 | |
672 @item Syntax Table | |
673 The syntax table tells Emacs which characters are part of a word, | |
674 which characters balance each other like parentheses, etc. | |
675 @xref{Syntax}. | |
676 | |
677 @item Tag Table | |
678 A tag table is a file that serves as an index to the function | |
679 definitions in one or more other files. @xref{Tags}. | |
680 | |
681 @item Termscript File | |
682 A termscript file contains a record of all characters Emacs sent to | |
683 the terminal. It is used for tracking down bugs in Emacs redisplay. | |
684 Emacs does not make a termscript file unless explicitly instructed to do | |
685 so. | |
686 @xref{Bugs}. | |
687 | |
688 @item Text | |
689 Text has two meanings (@pxref{Text}): | |
690 | |
691 @itemize @bullet | |
692 @item | |
693 Data consisting of a sequence of characters, as opposed to binary | |
694 numbers, images, graphics commands, executable programs, and the like. | |
695 The contents of an Emacs buffer are always text in this sense. | |
696 @item | |
697 Data consisting of written human language, as opposed to programs, | |
698 or something that follows the stylistic conventions of human language. | |
699 @end itemize | |
700 | |
701 @item Top Level | |
702 Top level is the normal state of Emacs, in which you are editing the | |
703 text of the file you have visited. You are at top level whenever you | |
704 are not in a recursive editing level (q.v.@:) or the minibuffer | |
705 (q.v.@:), and not in the middle of a command. You can get back to top | |
706 level by aborting (q.v.@:) and quitting (q.v.@:). @xref{Quitting}. | |
707 | |
708 @item Transposition | |
709 Transposing two units of text means putting each one into the place | |
710 formerly occupied by the other. There are Emacs commands to transpose | |
711 two adjacent characters, words, sexps (q.v.@:), or lines | |
712 (@pxref{Transpose}). | |
713 | |
714 @item Truncation | |
715 Truncating text lines in the display means leaving out any text on a | |
716 line that does not fit within the right margin of the window | |
717 displaying it. See also `continuation line'. | |
718 @xref{Basic,Truncation,Basic Editing}. | |
719 | |
720 @item Undoing | |
721 Undoing means making your previous editing go in reverse, bringing | |
722 back the text that existed earlier in the editing session. | |
723 @xref{Undo}. | |
724 | |
725 @item Variable | |
726 A variable is Lisp object that can store an arbitrary value. Emacs uses | |
727 some variables for internal purposes, and has others (known as `options' | |
728 (q.v.@:)) you can set to control the behavior of Emacs. The variables | |
729 used in Emacs that you are likely to be interested in are listed in the | |
730 Variables Index of this manual. @xref{Variables}, for information on | |
731 variables. | |
732 | |
733 @item Visiting | |
734 Visiting a file means loading its contents into a buffer (q.v.@:) | |
735 where they can be edited. @xref{Visiting}. | |
736 | |
737 @item Whitespace | |
738 Whitespace is any run of consecutive formatting characters (spaces, | |
739 tabs, newlines, and backspaces). | |
740 | |
741 @item Widening | |
742 Widening is removing any restriction (q.v.@:) on the current buffer; | |
743 it is the opposite of narrowing (q.v.@:). @xref{Narrowing}. | |
744 | |
745 @item Window | |
746 Emacs divides the frame into one or more windows, each of which can | |
747 display the contents of one buffer (q.v.@:) at any time. | |
748 @xref{Frame}, for basic information on how Emacs uses the frame. | |
749 @xref{Windows}, for commands to control the use of windows. Note that if | |
750 you are running Emacs under X, terminology can be confusing: Each Emacs | |
751 frame occupies a separate X window and can, in turn, be divided into | |
752 different subwindows. | |
753 | |
754 @item Word Abbrev | |
755 Synonymous with `abbrev'. | |
756 | |
757 @item Word Search | |
758 Word search is searching for a sequence of words, considering the | |
759 punctuation between them as insignificant. @xref{Word Search}. | |
760 | |
761 @item Yanking | |
762 Yanking means reinserting text previously killed. It can be used to | |
763 undo a mistaken kill, or for copying or moving text. Some other | |
764 systems call this ``pasting''. @xref{Yanking}. | |
765 @end table |