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6bf7aab6 | 1 | @c This is part of the Emacs manual. |
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2 | @c Copyright (C) 1985, 86, 87, 93, 94, 95, 97, 2000 |
3 | @c Free Software Foundation, Inc. | |
6bf7aab6 DL |
4 | @c See file emacs.texi for copying conditions. |
5 | @iftex | |
6 | @chapter Miscellaneous Commands | |
7 | ||
8 | This chapter contains several brief topics that do not fit anywhere | |
9 | else: reading netnews, running shell commands and shell subprocesses, | |
10 | using a single shared Emacs for utilities that expect to run an editor | |
11 | as a subprocess, printing hardcopy, sorting text, narrowing display to | |
12 | part of the buffer, editing double-column files and binary files, saving | |
13 | an Emacs session for later resumption, emulating other editors, and | |
14 | various diversions and amusements. | |
15 | ||
16 | @end iftex | |
17 | @node Gnus, Shell, Calendar/Diary, Top | |
18 | @section Gnus | |
19 | @cindex Gnus | |
20 | @cindex reading netnews | |
21 | ||
22 | Gnus is an Emacs package primarily designed for reading and posting | |
23 | Usenet news. It can also be used to read and respond to messages from a | |
24 | number of other sources---mail, remote directories, digests, and so on. | |
25 | ||
26 | Here we introduce Gnus and describe several basic features. | |
27 | @ifinfo | |
28 | For full details, see @ref{Top, Gnus,, gnus, The Gnus Manual}. | |
29 | @end ifinfo | |
30 | @iftex | |
31 | For full details on Gnus, type @kbd{M-x info} and then select the Gnus | |
32 | manual. | |
33 | @end iftex | |
34 | ||
35 | @findex gnus | |
36 | To start Gnus, type @kbd{M-x gnus @key{RET}}. | |
37 | ||
38 | @menu | |
39 | * Buffers of Gnus:: The group, summary, and article buffers. | |
40 | * Gnus Startup:: What you should know about starting Gnus. | |
41 | * Summary of Gnus:: A short description of the basic Gnus commands. | |
42 | @end menu | |
43 | ||
44 | @node Buffers of Gnus | |
45 | @subsection Gnus Buffers | |
46 | ||
47 | As opposed to most normal Emacs packages, Gnus uses a number of | |
48 | different buffers to display information and to receive commands. The | |
49 | three buffers users spend most of their time in are the @dfn{group | |
50 | buffer}, the @dfn{summary buffer} and the @dfn{article buffer}. | |
51 | ||
52 | The @dfn{group buffer} contains a list of groups. This is the first | |
53 | buffer Gnus displays when it starts up. It normally displays only the | |
54 | groups to which you subscribe and that contain unread articles. Use | |
55 | this buffer to select a specific group. | |
56 | ||
57 | The @dfn{summary buffer} lists one line for each article in a single | |
58 | group. By default, the author, the subject and the line number are | |
59 | displayed for each article, but this is customizable, like most aspects | |
60 | of Gnus display. The summary buffer is created when you select a group | |
61 | in the group buffer, and is killed when you exit the group. Use this | |
62 | buffer to select an article. | |
63 | ||
64 | The @dfn{article buffer} displays the article. In normal Gnus usage, | |
65 | you don't select this buffer---all useful article-oriented commands work | |
66 | in the summary buffer. But you can select the article buffer, and | |
67 | execute all Gnus commands from that buffer, if you want to. | |
68 | ||
69 | @node Gnus Startup | |
70 | @subsection When Gnus Starts Up | |
71 | ||
72 | At startup, Gnus reads your @file{.newsrc} news initialization file | |
73 | and attempts to communicate with the local news server, which is a | |
74 | repository of news articles. The news server need not be the same | |
75 | computer you are logged in on. | |
76 | ||
77 | If you start Gnus and connect to the server, but do not see any | |
78 | newsgroups listed in the group buffer, type @kbd{L} or @kbd{A k} to get | |
79 | a listing of all the groups. Then type @kbd{u} to toggle | |
80 | subscription to groups. | |
81 | ||
82 | The first time you start Gnus, Gnus subscribes you to a few selected | |
83 | groups. All other groups start out as @dfn{killed groups} for you; you | |
84 | can list them with @kbd{A k}. All new groups that subsequently come to | |
85 | exist at the news server become @dfn{zombie groups} for you; type @kbd{A | |
86 | z} to list them. You can subscribe to a group shown in these lists | |
87 | using the @kbd{u} command. | |
88 | ||
89 | When you quit Gnus with @kbd{q}, it automatically records in your | |
90 | @file{.newsrc} and @file{.newsrc.eld} initialization files the | |
91 | subscribed or unsubscribed status of all groups. You should normally | |
92 | not edit these files manually, but you may if you know how. | |
93 | ||
94 | @node Summary of Gnus | |
95 | @subsection Summary of Gnus Commands | |
96 | ||
97 | Reading news is a two step process: | |
98 | ||
99 | @enumerate | |
100 | @item | |
101 | Choose a group in the group buffer. | |
102 | ||
103 | @item | |
104 | Select articles from the summary buffer. Each article selected is | |
105 | displayed in the article buffer in a large window, below the summary | |
106 | buffer in its small window. | |
107 | @end enumerate | |
108 | ||
109 | Each Gnus buffer has its own special commands; however, the meanings | |
110 | of any given key in the various Gnus buffers are usually analogous, even | |
111 | if not identical. Here are commands for the group and summary buffers: | |
112 | ||
113 | @table @kbd | |
114 | @kindex q @r{(Gnus Group mode)} | |
115 | @findex gnus-group-exit | |
116 | @item q | |
117 | In the group buffer, update your @file{.newsrc} initialization file | |
118 | and quit Gnus. | |
119 | ||
120 | In the summary buffer, exit the current group and return to the | |
121 | group buffer. Thus, typing @kbd{q} twice quits Gnus. | |
122 | ||
123 | @kindex L @r{(Gnus Group mode)} | |
124 | @findex gnus-group-list-all-groups | |
125 | @item L | |
126 | In the group buffer, list all the groups available on your news | |
127 | server (except those you have killed). This may be a long list! | |
128 | ||
129 | @kindex l @r{(Gnus Group mode)} | |
130 | @findex gnus-group-list-groups | |
131 | @item l | |
132 | In the group buffer, list only the groups to which you subscribe and | |
133 | which contain unread articles. | |
134 | ||
135 | @kindex u @r{(Gnus Group mode)} | |
136 | @findex gnus-group-unsubscribe-current-group | |
137 | @cindex subscribe groups | |
138 | @cindex unsubscribe groups | |
139 | @item u | |
140 | In the group buffer, unsubscribe from (or subscribe to) the group listed | |
141 | in the line that point is on. When you quit Gnus by typing @kbd{q}, | |
142 | Gnus lists in your @file{.newsrc} file which groups you have subscribed | |
143 | to. The next time you start Gnus, you won't see this group, | |
144 | because Gnus normally displays only subscribed-to groups. | |
145 | ||
146 | @kindex C-k @r{(Gnus)} | |
147 | @findex gnus-group-kill-group | |
148 | @item C-k | |
149 | In the group buffer, ``kill'' the current line's group---don't | |
150 | even list it in @file{.newsrc} from now on. This affects future | |
151 | Gnus sessions as well as the present session. | |
152 | ||
153 | When you quit Gnus by typing @kbd{q}, Gnus writes information | |
154 | in the file @file{.newsrc} describing all newsgroups except those you | |
155 | have ``killed.'' | |
156 | ||
157 | @kindex SPC @r{(Gnus)} | |
158 | @findex gnus-group-read-group | |
159 | @item @key{SPC} | |
160 | In the group buffer, select the group on the line under the cursor | |
161 | and display the first unread article in that group. | |
162 | ||
163 | @need 1000 | |
164 | In the summary buffer, | |
165 | ||
166 | @itemize @bullet | |
167 | @item | |
168 | Select the article on the line under the cursor if none is selected. | |
169 | ||
170 | @item | |
171 | Scroll the text of the selected article (if there is one). | |
172 | ||
173 | @item | |
174 | Select the next unread article if at the end of the current article. | |
175 | @end itemize | |
176 | ||
177 | Thus, you can move through all the articles by repeatedly typing @key{SPC}. | |
178 | ||
179 | @kindex DEL @r{(Gnus)} | |
180 | @item @key{DEL} | |
181 | In the group buffer, move point to the previous group containing | |
182 | unread articles. | |
183 | ||
184 | @findex gnus-summary-prev-page | |
185 | In the summary buffer, scroll the text of the article backwards. | |
186 | ||
187 | @kindex n @r{(Gnus)} | |
188 | @findex gnus-group-next-unread-group | |
189 | @findex gnus-summary-next-unread-article | |
190 | @item n | |
191 | Move point to the next unread group, or select the next unread article. | |
192 | ||
193 | @kindex p @r{(Gnus)} | |
194 | @findex gnus-group-prev-unread-group | |
195 | @findex gnus-summary-prev-unread-article | |
196 | @item p | |
197 | Move point to the previous unread group, or select the previous | |
198 | unread article. | |
199 | ||
200 | @kindex C-n @r{(Gnus Group mode)} | |
201 | @findex gnus-group-next-group | |
202 | @kindex C-p @r{(Gnus Group mode)} | |
203 | @findex gnus-group-prev-group | |
204 | @kindex C-n @r{(Gnus Summary mode)} | |
205 | @findex gnus-summary-next-subject | |
206 | @kindex C-p @r{(Gnus Summary mode)} | |
207 | @findex gnus-summary-prev-subject | |
208 | @item C-n | |
209 | @itemx C-p | |
210 | Move point to the next or previous item, even if it is marked as read. | |
211 | This does not select the article or group on that line. | |
212 | ||
213 | @kindex s @r{(Gnus Summary mode)} | |
214 | @findex gnus-summary-isearch-article | |
215 | @item s | |
216 | In the summary buffer, do an incremental search of the current text in | |
217 | the article buffer, just as if you switched to the article buffer and | |
218 | typed @kbd{C-s}. | |
219 | ||
220 | @kindex M-s @r{(Gnus Summary mode)} | |
221 | @findex gnus-summary-search-article-forward | |
222 | @item M-s @var{regexp} @key{RET} | |
223 | In the summary buffer, search forward for articles containing a match | |
224 | for @var{regexp}. | |
225 | ||
226 | @end table | |
227 | ||
228 | @ignore | |
229 | @node Where to Look | |
230 | @subsection Where to Look Further | |
231 | ||
232 | @c Too many references to the name of the manual if done with xref in TeX! | |
233 | Gnus is powerful and customizable. Here are references to a few | |
234 | @ifinfo | |
235 | additional topics: | |
236 | ||
237 | @end ifinfo | |
238 | @iftex | |
239 | additional topics in @cite{The Gnus Manual}: | |
240 | ||
241 | @itemize @bullet | |
242 | @item | |
243 | Follow discussions on specific topics.@* | |
244 | See section ``Threading.'' | |
245 | ||
246 | @item | |
247 | Read digests. See section ``Document Groups.'' | |
248 | ||
249 | @item | |
250 | Refer to and jump to the parent of the current article.@* | |
251 | See section ``Finding the Parent.'' | |
252 | ||
253 | @item | |
254 | Refer to articles by using Message-IDs included in the messages.@* | |
255 | See section ``Article Keymap.'' | |
256 | ||
257 | @item | |
258 | Save articles. See section ``Saving Articles.'' | |
259 | ||
260 | @item | |
261 | Have Gnus score articles according to various criteria, like author | |
262 | name, subject, or string in the body of the articles.@* | |
263 | See section ``Scoring.'' | |
264 | ||
265 | @item | |
266 | Send an article to a newsgroup.@* | |
267 | See section ``Composing Messages.'' | |
268 | @end itemize | |
269 | @end iftex | |
270 | @ifinfo | |
271 | @itemize @bullet | |
272 | @item | |
273 | Follow discussions on specific topics.@* | |
274 | @xref{Threading, , Reading Based on Conversation Threads, | |
275 | gnus, The Gnus Manual}. | |
276 | ||
277 | @item | |
278 | Read digests. @xref{Document Groups, , , gnus, The Gnus Manual}. | |
279 | ||
280 | @item | |
281 | Refer to and jump to the parent of the current article.@* | |
282 | @xref{Finding the Parent, , , gnus, The Gnus Manual}. | |
283 | ||
284 | @item | |
285 | Refer to articles by using Message-IDs included in the messages.@* | |
286 | @xref{Article Keymap, , , gnus, The Gnus Manual}. | |
287 | ||
288 | @item | |
289 | Save articles. @xref{Saving Articles, , , gnus, The Gnus Manual}. | |
290 | ||
291 | @item | |
292 | Have Gnus score articles according to various criteria, like author | |
293 | name, subject, or string in the body of the articles.@* | |
294 | @xref{Scoring, , , gnus, The Gnus Manual}. | |
295 | ||
296 | @item | |
297 | Send an article to a newsgroup.@* | |
298 | @xref{Composing Messages, , , gnus, The Gnus Manual}. | |
299 | @end itemize | |
300 | @end ifinfo | |
301 | @end ignore | |
302 | ||
303 | @node Shell, Emacs Server, Gnus, Top | |
304 | @section Running Shell Commands from Emacs | |
305 | @cindex subshell | |
306 | @cindex shell commands | |
307 | ||
308 | Emacs has commands for passing single command lines to inferior shell | |
309 | processes; it can also run a shell interactively with input and output to | |
310 | an Emacs buffer named @samp{*shell*}. | |
311 | ||
312 | @table @kbd | |
313 | @item M-! @var{cmd} @key{RET} | |
314 | Run the shell command line @var{cmd} and display the output | |
315 | (@code{shell-command}). | |
316 | @item M-| @var{cmd} @key{RET} | |
317 | Run the shell command line @var{cmd} with region contents as input; | |
318 | optionally replace the region with the output | |
319 | (@code{shell-command-on-region}). | |
320 | @item M-x shell | |
321 | Run a subshell with input and output through an Emacs buffer. | |
322 | You can then give commands interactively. | |
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323 | @item M-x term |
324 | Run a subshell with input and output through an Emacs buffer. | |
325 | You can then give commands interactively. | |
326 | Full terminal emulation is available. | |
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327 | @end table |
328 | ||
329 | @menu | |
330 | * Single Shell:: How to run one shell command and return. | |
331 | * Interactive Shell:: Permanent shell taking input via Emacs. | |
332 | * Shell Mode:: Special Emacs commands used with permanent shell. | |
333 | * History: Shell History. Repeating previous commands in a shell buffer. | |
334 | * Options: Shell Options. Options for customizing Shell mode. | |
3b65ce47 DL |
335 | * Terminal emulator:: An Emacs window as a terminal emulator. |
336 | * Term Mode:: Special Emacs commands used in Term mode. | |
337 | * Paging in Term:: Paging in the terminal emulator. | |
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338 | * Remote Host:: Connecting to another computer. |
339 | @end menu | |
340 | ||
341 | @node Single Shell | |
342 | @subsection Single Shell Commands | |
343 | ||
344 | @kindex M-! | |
345 | @findex shell-command | |
346 | @kbd{M-!} (@code{shell-command}) reads a line of text using the | |
347 | minibuffer and executes it as a shell command in a subshell made just | |
348 | for that command. Standard input for the command comes from the null | |
349 | device. If the shell command produces any output, the output goes into | |
350 | an Emacs buffer named @samp{*Shell Command Output*}, which is displayed | |
351 | in another window but not selected. A numeric argument, as in @kbd{M-1 | |
352 | M-!}, directs this command to insert any output into the current buffer. | |
353 | In that case, point is left before the output and the mark is set after | |
354 | the output. | |
355 | ||
356 | If the shell command line ends in @samp{&}, it runs asynchronously. | |
357 | For a synchronous shell command, @code{shell-command} returns the | |
358 | command's exit status (0 means success), when it is called from a Lisp | |
359 | program. | |
360 | ||
361 | @kindex M-| | |
362 | @findex shell-command-on-region | |
363 | @kbd{M-|} (@code{shell-command-on-region}) is like @kbd{M-!} but | |
364 | passes the contents of the region as the standard input to the shell | |
365 | command, instead of no input. If a numeric argument is used, meaning | |
366 | insert the output in the current buffer, then the old region is deleted | |
367 | first and the output replaces it as the contents of the region. It | |
368 | returns the command's exit status when it is called from a Lisp program. | |
369 | ||
370 | @vindex shell-file-name | |
371 | @cindex environment | |
372 | Both @kbd{M-!} and @kbd{M-|} use @code{shell-file-name} to specify the | |
60a96371 | 373 | shell to use. This variable is initialized based on your @env{SHELL} |
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374 | environment variable when Emacs is started. If the file name does not |
375 | specify a directory, the directories in the list @code{exec-path} are | |
376 | searched; this list is initialized based on the environment variable | |
60a96371 | 377 | @env{PATH} when Emacs is started. Your @file{.emacs} file can override |
6bf7aab6 DL |
378 | either or both of these default initializations.@refill |
379 | ||
380 | Both @kbd{M-!} and @kbd{M-|} wait for the shell command to complete. | |
381 | To stop waiting, type @kbd{C-g} to quit; that terminates the shell | |
382 | command with the signal @code{SIGINT}---the same signal that @kbd{C-c} | |
383 | normally generates in the shell. Emacs waits until the command actually | |
384 | terminates. If the shell command doesn't stop (because it ignores the | |
385 | @code{SIGINT} signal), type @kbd{C-g} again; this sends the command a | |
386 | @code{SIGKILL} signal which is impossible to ignore. | |
387 | ||
388 | To specify a coding system for @kbd{M-!} or @kbd{M-|}, use the command | |
389 | @kbd{C-x @key{RET} c} immediately beforehand. @xref{Specify Coding}. | |
390 | ||
391 | @vindex shell-command-default-error-buffer | |
392 | Error output from the command is normally intermixed with the regular | |
393 | output. If you set the variable | |
394 | @code{shell-command-default-error-buffer} to a string, which is a buffer | |
395 | name, error output is inserted before point in the buffer of that name. | |
396 | ||
397 | @node Interactive Shell | |
398 | @subsection Interactive Inferior Shell | |
399 | ||
400 | @findex shell | |
401 | To run a subshell interactively, putting its typescript in an Emacs | |
402 | buffer, use @kbd{M-x shell}. This creates (or reuses) a buffer named | |
403 | @samp{*shell*} and runs a subshell with input coming from and output going | |
404 | to that buffer. That is to say, any ``terminal output'' from the subshell | |
405 | goes into the buffer, advancing point, and any ``terminal input'' for | |
406 | the subshell comes from text in the buffer. To give input to the subshell, | |
407 | go to the end of the buffer and type the input, terminated by @key{RET}. | |
408 | ||
409 | Emacs does not wait for the subshell to do anything. You can switch | |
410 | windows or buffers and edit them while the shell is waiting, or while it is | |
411 | running a command. Output from the subshell waits until Emacs has time to | |
412 | process it; this happens whenever Emacs is waiting for keyboard input or | |
413 | for time to elapse. | |
414 | ||
415 | To make multiple subshells, rename the buffer @samp{*shell*} to | |
416 | something different using @kbd{M-x rename-uniquely}. Then type @kbd{M-x | |
417 | shell} again to create a new buffer @samp{*shell*} with its own | |
418 | subshell. If you rename this buffer as well, you can create a third | |
419 | one, and so on. All the subshells run independently and in parallel. | |
420 | ||
421 | @vindex explicit-shell-file-name | |
60a96371 GM |
422 | @cindex @env{ESHELL} environment variable |
423 | @cindex @env{SHELL} environment variable | |
6bf7aab6 DL |
424 | The file name used to load the subshell is the value of the variable |
425 | @code{explicit-shell-file-name}, if that is non-@code{nil}. Otherwise, | |
60a96371 GM |
426 | the environment variable @env{ESHELL} is used, or the environment |
427 | variable @env{SHELL} if there is no @env{ESHELL}. If the file name | |
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428 | specified is relative, the directories in the list @code{exec-path} are |
429 | searched; this list is initialized based on the environment variable | |
60a96371 | 430 | @env{PATH} when Emacs is started. Your @file{.emacs} file can override |
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431 | either or both of these default initializations. |
432 | ||
433 | To specify a coding system for the shell, you can use the command | |
434 | @kbd{C-x @key{RET} c} immediately before @kbd{M-x shell}. You can also | |
435 | specify a coding system after starting the shell by using @kbd{C-x | |
436 | @key{RET} p} in the shell buffer. @xref{Specify Coding}. | |
437 | ||
438 | As soon as the subshell is started, it is sent as input the contents | |
439 | of the file @file{~/.emacs_@var{shellname}}, if that file exists, where | |
440 | @var{shellname} is the name of the file that the shell was loaded from. | |
441 | For example, if you use bash, the file sent to it is | |
442 | @file{~/.emacs_bash}. | |
443 | ||
444 | @vindex shell-pushd-regexp | |
445 | @vindex shell-popd-regexp | |
446 | @vindex shell-cd-regexp | |
447 | @code{cd}, @code{pushd} and @code{popd} commands given to the inferior | |
448 | shell are watched by Emacs so it can keep the @samp{*shell*} buffer's | |
449 | default directory the same as the shell's working directory. These | |
450 | commands are recognized syntactically by examining lines of input that are | |
451 | sent. If you use aliases for these commands, you can tell Emacs to | |
452 | recognize them also. For example, if the value of the variable | |
453 | @code{shell-pushd-regexp} matches the beginning of a shell command line, | |
454 | that line is regarded as a @code{pushd} command. Change this variable when | |
455 | you add aliases for @samp{pushd}. Likewise, @code{shell-popd-regexp} and | |
456 | @code{shell-cd-regexp} are used to recognize commands with the meaning of | |
457 | @samp{popd} and @samp{cd}. These commands are recognized only at the | |
458 | beginning of a shell command line.@refill | |
459 | ||
460 | @vindex shell-set-directory-error-hook | |
461 | If Emacs gets an error while trying to handle what it believes is a | |
462 | @samp{cd}, @samp{pushd} or @samp{popd} command, it runs the hook | |
463 | @code{shell-set-directory-error-hook} (@pxref{Hooks}). | |
464 | ||
465 | @findex dirs | |
466 | If Emacs does not properly track changes in the current directory of | |
467 | the subshell, use the command @kbd{M-x dirs} to ask the shell what its | |
468 | current directory is. This command works for shells that support the | |
469 | most common command syntax; it may not work for unusual shells. | |
470 | ||
471 | @findex dirtrack-mode | |
472 | You can also use @kbd{M-x dirtrack-mode} to enable (or disable) an | |
473 | alternative and more aggressive method of tracking changes in the | |
474 | current directory. | |
475 | ||
60a96371 | 476 | Emacs defines the environment variable @env{EMACS} in the subshell, |
6bf7aab6 DL |
477 | with value @code{t}. A shell script can check this variable to |
478 | determine whether it has been run from an Emacs subshell. | |
479 | ||
480 | @node Shell Mode | |
481 | @subsection Shell Mode | |
482 | @cindex Shell mode | |
483 | @cindex mode, Shell | |
484 | ||
485 | Shell buffers use Shell mode, which defines several special keys | |
486 | attached to the @kbd{C-c} prefix. They are chosen to resemble the usual | |
487 | editing and job control characters present in shells that are not under | |
488 | Emacs, except that you must type @kbd{C-c} first. Here is a complete list | |
489 | of the special key bindings of Shell mode: | |
490 | ||
491 | @table @kbd | |
492 | @item @key{RET} | |
493 | @kindex RET @r{(Shell mode)} | |
494 | @findex comint-send-input | |
495 | At end of buffer send line as input; otherwise, copy current line to end | |
496 | of buffer and send it (@code{comint-send-input}). When a line is | |
497 | copied, any text at the beginning of the line that matches the variable | |
498 | @code{shell-prompt-pattern} is left out; this variable's value should be | |
499 | a regexp string that matches the prompts that your shell uses. | |
500 | ||
501 | @item @key{TAB} | |
502 | @kindex TAB @r{(Shell mode)} | |
503 | @findex comint-dynamic-complete | |
504 | Complete the command name or file name before point in the shell buffer | |
505 | (@code{comint-dynamic-complete}). @key{TAB} also completes history | |
506 | references (@pxref{History References}) and environment variable names. | |
507 | ||
508 | @vindex shell-completion-fignore | |
509 | @vindex comint-completion-fignore | |
510 | The variable @code{shell-completion-fignore} specifies a list of file | |
511 | name extensions to ignore in Shell mode completion. The default setting | |
512 | ignores file names ending in @samp{~}, @samp{#} or @samp{%}. Other | |
513 | related Comint modes use the variable @code{comint-completion-fignore} | |
514 | instead. | |
515 | ||
516 | @item M-? | |
517 | @kindex M-? @r{(Shell mode)} | |
518 | @findex comint-dynamic-list-filename@dots{} | |
519 | Display temporarily a list of the possible completions of the file name | |
520 | before point in the shell buffer | |
521 | (@code{comint-dynamic-list-filename-completions}). | |
522 | ||
523 | @item C-d | |
524 | @kindex C-d @r{(Shell mode)} | |
525 | @findex comint-delchar-or-maybe-eof | |
027f547a | 526 | Either delete a character or send @sc{eof} |
6bf7aab6 | 527 | (@code{comint-delchar-or-maybe-eof}). Typed at the end of the shell |
027f547a | 528 | buffer, @kbd{C-d} sends @sc{eof} to the subshell. Typed at any other |
6bf7aab6 DL |
529 | position in the buffer, @kbd{C-d} deletes a character as usual. |
530 | ||
531 | @item C-c C-a | |
532 | @kindex C-c C-a @r{(Shell mode)} | |
533 | @findex comint-bol | |
534 | Move to the beginning of the line, but after the prompt if any | |
535 | (@code{comint-bol}). If you repeat this command twice in a row, the | |
536 | second time it moves back to the process mark, which is the beginning of | |
537 | the input that you have not yet sent to the subshell. (Normally that is | |
538 | the same place---the end of the prompt on this line---but after @kbd{C-c | |
539 | @key{SPC}} the process mark may be in a previous line.) | |
540 | ||
541 | @item C-c @key{SPC} | |
542 | Accumulate multiple lines of input, then send them together. This | |
543 | command inserts a newline before point, but does not send the preceding | |
544 | text as input to the subshell---at least, not yet. Both lines, the one | |
545 | before this newline and the one after, will be sent together (along with | |
546 | the newline that separates them), when you type @key{RET}. | |
547 | ||
548 | @item C-c C-u | |
549 | @kindex C-c C-u @r{(Shell mode)} | |
550 | @findex comint-kill-input | |
551 | Kill all text pending at end of buffer to be sent as input | |
552 | (@code{comint-kill-input}). | |
553 | ||
554 | @item C-c C-w | |
555 | @kindex C-c C-w @r{(Shell mode)} | |
556 | Kill a word before point (@code{backward-kill-word}). | |
557 | ||
558 | @item C-c C-c | |
559 | @kindex C-c C-c @r{(Shell mode)} | |
560 | @findex comint-interrupt-subjob | |
561 | Interrupt the shell or its current subjob if any | |
562 | (@code{comint-interrupt-subjob}). This command also kills | |
563 | any shell input pending in the shell buffer and not yet sent. | |
564 | ||
565 | @item C-c C-z | |
566 | @kindex C-c C-z @r{(Shell mode)} | |
567 | @findex comint-stop-subjob | |
568 | Stop the shell or its current subjob if any (@code{comint-stop-subjob}). | |
569 | This command also kills any shell input pending in the shell buffer and | |
570 | not yet sent. | |
571 | ||
572 | @item C-c C-\ | |
573 | @findex comint-quit-subjob | |
574 | @kindex C-c C-\ @r{(Shell mode)} | |
575 | Send quit signal to the shell or its current subjob if any | |
576 | (@code{comint-quit-subjob}). This command also kills any shell input | |
577 | pending in the shell buffer and not yet sent. | |
578 | ||
579 | @item C-c C-o | |
580 | @kindex C-c C-o @r{(Shell mode)} | |
581 | @findex comint-kill-output | |
582 | Kill the last batch of output from a shell command | |
583 | (@code{comint-kill-output}). This is useful if a shell command spews | |
584 | out lots of output that just gets in the way. | |
585 | ||
586 | @item C-c C-r | |
587 | @itemx C-M-l | |
588 | @kindex C-c C-r @r{(Shell mode)} | |
589 | @kindex C-M-l @r{(Shell mode)} | |
590 | @findex comint-show-output | |
591 | Scroll to display the beginning of the last batch of output at the top | |
592 | of the window; also move the cursor there (@code{comint-show-output}). | |
593 | ||
594 | @item C-c C-e | |
595 | @kindex C-c C-e @r{(Shell mode)} | |
596 | @findex comint-show-maximum-output | |
597 | Scroll to put the end of the buffer at the bottom of the window | |
598 | (@code{comint-show-maximum-output}). | |
599 | ||
600 | @item C-c C-f | |
601 | @kindex C-c C-f @r{(Shell mode)} | |
602 | @findex shell-forward-command | |
603 | @vindex shell-command-regexp | |
604 | Move forward across one shell command, but not beyond the current line | |
605 | (@code{shell-forward-command}). The variable @code{shell-command-regexp} | |
606 | specifies how to recognize the end of a command. | |
607 | ||
608 | @item C-c C-b | |
609 | @kindex C-c C-b @r{(Shell mode)} | |
610 | @findex shell-backward-command | |
611 | Move backward across one shell command, but not beyond the current line | |
612 | (@code{shell-backward-command}). | |
613 | ||
614 | @item C-c C-l | |
615 | @kindex C-c C-l @r{(Shell mode)} | |
616 | @findex comint-dynamic-list-input-ring | |
617 | Display the buffer's history of shell commands in another window | |
618 | (@code{comint-dynamic-list-input-ring}). | |
619 | ||
620 | @item M-x dirs | |
621 | Ask the shell what its current directory is, so that Emacs can agree | |
622 | with the shell. | |
623 | ||
624 | @item M-x send-invisible @key{RET} @var{text} @key{RET} | |
625 | @findex send-invisible | |
626 | Send @var{text} as input to the shell, after reading it without | |
627 | echoing. This is useful when a shell command runs a program that asks | |
628 | for a password. | |
629 | ||
630 | Alternatively, you can arrange for Emacs to notice password prompts | |
631 | and turn off echoing for them, as follows: | |
632 | ||
633 | @example | |
634 | (add-hook 'comint-output-filter-functions | |
635 | 'comint-watch-for-password-prompt) | |
636 | @end example | |
637 | ||
638 | @item M-x comint-continue-subjob | |
639 | @findex comint-continue-subjob | |
640 | Continue the shell process. This is useful if you accidentally suspend | |
641 | the shell process.@footnote{You should not suspend the shell process. | |
642 | Suspending a subjob of the shell is a completely different matter---that | |
643 | is normal practice, but you must use the shell to continue the subjob; | |
644 | this command won't do it.} | |
645 | ||
646 | @item M-x comint-strip-ctrl-m | |
647 | @findex comint-strip-ctrl-m | |
648 | Discard all control-M characters from the current group of shell output. | |
649 | The most convenient way to use this command is to make it run | |
650 | automatically when you get output from the subshell. To do that, | |
651 | evaluate this Lisp expression: | |
652 | ||
653 | @example | |
654 | (add-hook 'comint-output-filter-functions | |
655 | 'comint-strip-ctrl-m) | |
656 | @end example | |
657 | ||
658 | @item M-x comint-truncate-buffer | |
659 | @findex comint-truncate-buffer | |
660 | This command truncates the shell buffer to a certain maximum number of | |
661 | lines, specified by the variable @code{comint-buffer-maximum-size}. | |
662 | Here's how to do this automatically each time you get output from the | |
663 | subshell: | |
664 | ||
665 | @example | |
666 | (add-hook 'comint-output-filter-functions | |
667 | 'comint-truncate-buffer) | |
668 | @end example | |
669 | @end table | |
670 | ||
671 | Shell mode also customizes the paragraph commands so that only shell | |
672 | prompts start new paragraphs. Thus, a paragraph consists of an input | |
673 | command plus the output that follows it in the buffer. | |
674 | ||
675 | @cindex Comint mode | |
676 | @cindex mode, Comint | |
677 | Shell mode is a derivative of Comint mode, a general-purpose mode for | |
678 | communicating with interactive subprocesses. Most of the features of | |
679 | Shell mode actually come from Comint mode, as you can see from the | |
680 | command names listed above. The special features of Shell mode in | |
681 | particular include the choice of regular expression for detecting | |
682 | prompts, the directory tracking feature, and a few user commands. | |
683 | ||
684 | Other Emacs features that use variants of Comint mode include GUD | |
685 | (@pxref{Debuggers}) and @kbd{M-x run-lisp} (@pxref{External Lisp}). | |
686 | ||
687 | @findex comint-run | |
688 | You can use @kbd{M-x comint-run} to execute any program of your choice | |
689 | in a subprocess using unmodified Comint mode---without the | |
690 | specializations of Shell mode. | |
691 | ||
692 | @node Shell History | |
693 | @subsection Shell Command History | |
694 | ||
695 | Shell buffers support three ways of repeating earlier commands. You | |
696 | can use the same keys used in the minibuffer; these work much as they do | |
697 | in the minibuffer, inserting text from prior commands while point | |
698 | remains always at the end of the buffer. You can move through the | |
699 | buffer to previous inputs in their original place, then resubmit them or | |
700 | copy them to the end. Or you can use a @samp{!}-style history | |
701 | reference. | |
702 | ||
703 | @menu | |
704 | * Ring: Shell Ring. Fetching commands from the history list. | |
705 | * Copy: Shell History Copying. Moving to a command and then copying it. | |
706 | * History References:: Expanding @samp{!}-style history references. | |
707 | @end menu | |
708 | ||
709 | @node Shell Ring | |
710 | @subsubsection Shell History Ring | |
711 | ||
712 | @table @kbd | |
713 | @findex comint-previous-input | |
714 | @kindex M-p @r{(Shell mode)} | |
715 | @item M-p | |
716 | Fetch the next earlier old shell command. | |
717 | ||
718 | @kindex M-n @r{(Shell mode)} | |
719 | @findex comint-next-input | |
720 | @item M-n | |
721 | Fetch the next later old shell command. | |
722 | ||
723 | @kindex M-r @r{(Shell mode)} | |
724 | @kindex M-s @r{(Shell mode)} | |
725 | @findex comint-previous-matching-input | |
726 | @findex comint-next-matching-input | |
727 | @item M-r @var{regexp} @key{RET} | |
728 | @itemx M-s @var{regexp} @key{RET} | |
729 | Search backwards or forwards for old shell commands that match @var{regexp}. | |
730 | ||
731 | @item C-c C-x @r{(Shell mode)} | |
732 | @findex comint-get-next-from-history | |
733 | Fetch the next subsequent command from the history. | |
734 | @end table | |
735 | ||
736 | Shell buffers provide a history of previously entered shell commands. To | |
737 | reuse shell commands from the history, use the editing commands @kbd{M-p}, | |
738 | @kbd{M-n}, @kbd{M-r} and @kbd{M-s}. These work just like the minibuffer | |
739 | history commands except that they operate on the text at the end of the | |
740 | shell buffer, where you would normally insert text to send to the shell. | |
741 | ||
742 | @kbd{M-p} fetches an earlier shell command to the end of the shell buffer. | |
743 | Successive use of @kbd{M-p} fetches successively earlier shell commands, | |
744 | each replacing any text that was already present as potential shell input. | |
745 | @kbd{M-n} does likewise except that it finds successively more recent shell | |
746 | commands from the buffer. | |
747 | ||
748 | The history search commands @kbd{M-r} and @kbd{M-s} read a regular | |
749 | expression and search through the history for a matching command. Aside | |
750 | from the choice of which command to fetch, they work just like @kbd{M-p} | |
751 | and @kbd{M-r}. If you enter an empty regexp, these commands reuse the | |
752 | same regexp used last time. | |
753 | ||
754 | When you find the previous input you want, you can resubmit it by | |
755 | typing @key{RET}, or you can edit it first and then resubmit it if you | |
756 | wish. | |
757 | ||
758 | Often it is useful to reexecute several successive shell commands that | |
759 | were previously executed in sequence. To do this, first find and | |
760 | reexecute the first command of the sequence. Then type @kbd{C-c C-x}; | |
761 | that will fetch the following command---the one that follows the command | |
762 | you just repeated. Then type @key{RET} to reexecute this command. You | |
763 | can reexecute several successive commands by typing @kbd{C-c C-x | |
764 | @key{RET}} over and over. | |
765 | ||
766 | These commands get the text of previous shell commands from a special | |
767 | history list, not from the shell buffer itself. Thus, editing the shell | |
768 | buffer, or even killing large parts of it, does not affect the history | |
769 | that these commands access. | |
770 | ||
771 | @vindex shell-input-ring-file-name | |
772 | Some shells store their command histories in files so that you can | |
773 | refer to previous commands from previous shell sessions. Emacs reads | |
774 | the command history file for your chosen shell, to initialize its own | |
775 | command history. The file name is @file{~/.bash_history} for bash, | |
776 | @file{~/.sh_history} for ksh, and @file{~/.history} for other shells. | |
777 | ||
778 | @node Shell History Copying | |
779 | @subsubsection Shell History Copying | |
780 | ||
781 | @table @kbd | |
782 | @kindex C-c C-p @r{(Shell mode)} | |
783 | @findex comint-previous-prompt | |
784 | @item C-c C-p | |
785 | Move point to the previous prompt (@code{comint-previous-prompt}). | |
786 | ||
787 | @kindex C-c C-n @r{(Shell mode)} | |
788 | @findex comint-next-prompt | |
789 | @item C-c C-n | |
790 | Move point to the following prompt (@code{comint-next-prompt}). | |
791 | ||
792 | @kindex C-c RET @r{(Shell mode)} | |
793 | @findex comint-copy-old-input | |
794 | @item C-c @key{RET} | |
795 | Copy the input command which point is in, inserting the copy at the end | |
796 | of the buffer (@code{comint-copy-old-input}). This is useful if you | |
797 | move point back to a previous command. After you copy the command, you | |
798 | can submit the copy as input with @key{RET}. If you wish, you can | |
799 | edit the copy before resubmitting it. | |
800 | @end table | |
801 | ||
802 | Moving to a previous input and then copying it with @kbd{C-c | |
803 | @key{RET}} produces the same results---the same buffer contents---that | |
804 | you would get by using @kbd{M-p} enough times to fetch that previous | |
805 | input from the history list. However, @kbd{C-c @key{RET}} copies the | |
806 | text from the buffer, which can be different from what is in the history | |
807 | list if you edit the input text in the buffer after it has been sent. | |
808 | ||
809 | @node History References | |
810 | @subsubsection Shell History References | |
811 | @cindex history reference | |
812 | ||
813 | Various shells including csh and bash support @dfn{history references} | |
814 | that begin with @samp{!} and @samp{^}. Shell mode can understand these | |
815 | constructs and perform the history substitution for you. If you insert | |
816 | a history reference and type @key{TAB}, this searches the input history | |
817 | for a matching command, performs substitution if necessary, and places | |
818 | the result in the buffer in place of the history reference. For | |
819 | example, you can fetch the most recent command beginning with @samp{mv} | |
820 | with @kbd{! m v @key{TAB}}. You can edit the command if you wish, and | |
821 | then resubmit the command to the shell by typing @key{RET}. | |
822 | ||
823 | @vindex shell-prompt-pattern | |
824 | @vindex comint-prompt-regexp | |
825 | History references take effect only following a shell prompt. The | |
826 | variable @code{shell-prompt-pattern} specifies how to recognize a shell | |
827 | prompt. Comint modes in general use the variable | |
828 | @code{comint-prompt-regexp} to specify how to find a prompt; Shell mode | |
829 | uses @code{shell-prompt-pattern} to set up the local value of | |
830 | @code{comint-prompt-regexp}. | |
831 | ||
832 | @vindex comint-input-autoexpand | |
833 | Shell mode can optionally expand history references in the buffer when | |
834 | you send them to the shell. To request this, set the variable | |
835 | @code{comint-input-autoexpand} to @code{input}. | |
836 | ||
837 | @findex comint-magic-space | |
838 | You can make @key{SPC} perform history expansion by binding @key{SPC} to | |
839 | the command @code{comint-magic-space}. | |
840 | ||
841 | @node Shell Options | |
842 | @subsection Shell Mode Options | |
843 | ||
844 | @vindex comint-scroll-to-bottom-on-input | |
845 | If the variable @code{comint-scroll-to-bottom-on-input} is | |
846 | non-@code{nil}, insertion and yank commands scroll the selected window | |
847 | to the bottom before inserting. | |
848 | ||
849 | @vindex comint-scroll-show-maximum-output | |
850 | If @code{comint-scroll-show-maximum-output} is non-@code{nil}, then | |
851 | scrolling due to arrival of output tries to place the last line of text | |
852 | at the bottom line of the window, so as to show as much useful text as | |
853 | possible. (This mimics the scrolling behavior of many terminals.) | |
854 | The default is @code{nil}. | |
855 | ||
856 | @vindex comint-scroll-to-bottom-on-output | |
857 | By setting @code{comint-scroll-to-bottom-on-output}, you can opt for | |
858 | having point jump to the end of the buffer whenever output arrives---no | |
859 | matter where in the buffer point was before. If the value is | |
860 | @code{this}, point jumps in the selected window. If the value is | |
861 | @code{all}, point jumps in each window that shows the comint buffer. If | |
862 | the value is @code{other}, point jumps in all nonselected windows that | |
863 | show the current buffer. The default value is @code{nil}, which means | |
864 | point does not jump to the end. | |
865 | ||
866 | @vindex comint-input-ignoredups | |
867 | The variable @code{comint-input-ignoredups} controls whether successive | |
868 | identical inputs are stored in the input history. A non-@code{nil} | |
869 | value means to omit an input that is the same as the previous input. | |
870 | The default is @code{nil}, which means to store each input even if it is | |
871 | equal to the previous input. | |
872 | ||
873 | @vindex comint-completion-addsuffix | |
874 | @vindex comint-completion-recexact | |
875 | @vindex comint-completion-autolist | |
876 | Three variables customize file name completion. The variable | |
877 | @code{comint-completion-addsuffix} controls whether completion inserts a | |
878 | space or a slash to indicate a fully completed file or directory name | |
879 | (non-@code{nil} means do insert a space or slash). | |
880 | @code{comint-completion-recexact}, if non-@code{nil}, directs @key{TAB} | |
881 | to choose the shortest possible completion if the usual Emacs completion | |
882 | algorithm cannot add even a single character. | |
883 | @code{comint-completion-autolist}, if non-@code{nil}, says to list all | |
884 | the possible completions whenever completion is not exact. | |
885 | ||
886 | @findex comint-dynamic-complete-variable | |
887 | The command @code{comint-dynamic-complete-variable} does variable-name | |
888 | completion using the environment variables as set within Emacs. The | |
889 | variables controlling file name completion apply to variable-name | |
890 | completion too. This command is normally available through the menu | |
891 | bar. | |
892 | ||
893 | @vindex shell-command-execonly | |
894 | Command completion normally considers only executable files. | |
895 | If you set @code{shell-command-execonly} to @code{nil}, | |
896 | it considers nonexecutable files as well. | |
897 | ||
898 | @findex shell-pushd-tohome | |
899 | @findex shell-pushd-dextract | |
900 | @findex shell-pushd-dunique | |
901 | You can configure the behavior of @samp{pushd}. Variables control | |
902 | whether @samp{pushd} behaves like @samp{cd} if no argument is given | |
903 | (@code{shell-pushd-tohome}), pop rather than rotate with a numeric | |
904 | argument (@code{shell-pushd-dextract}), and only add directories to the | |
905 | directory stack if they are not already on it | |
906 | (@code{shell-pushd-dunique}). The values you choose should match the | |
907 | underlying shell, of course. | |
908 | ||
3b65ce47 DL |
909 | @node Terminal emulator |
910 | @subsection Interactive Inferior Shell with Terminal Emulator | |
911 | @findex term | |
912 | ||
913 | To run a subshell in a terminal emulator, putting its typescript in an Emacs | |
914 | buffer, use @kbd{M-x term}. This creates (or reuses) a buffer named | |
915 | @samp{*term*} and runs a subshell with input coming from your keyboard and | |
916 | output going to that buffer. | |
917 | ||
918 | All the normal keys that you type are sent without any interpretation | |
919 | by Emacs directly to the subshell, as ``terminal input''. | |
920 | Any ``echo'' of your input is the responsibility of the subshell. | |
921 | (The exception is the terminal escape character, | |
922 | which by default is @kbd{C-c}. @xref{Term Mode}.) | |
923 | Any ``terminal output'' from the subshell goes into the buffer, | |
924 | advancing point. | |
925 | ||
926 | Some programs (such as Emacs itself) need to control the | |
927 | appearance on the terminal screen in detail. They do this by | |
928 | sending special control codes. The exact control | |
929 | codes needed vary from terminal to terminal, but nowadays | |
930 | most terminals and terminal emulators (including @code{xterm}) | |
931 | understand the ANSI-standard (VT100-style) escape sequences. | |
932 | Term mode also understands these escape sequences, | |
933 | and for each control code does the appropriate thing | |
934 | to change the buffer so that the appearance of the window | |
935 | matches what it would be on a real terminal. | |
936 | Thus you can actually run Emacs inside an Emacs Term window! | |
937 | ||
938 | Emacs does not wait for the subshell to do anything. You can switch | |
939 | windows or buffers and edit them while the shell is waiting, or while | |
940 | it is running a command. Output from the subshell waits until Emacs | |
941 | has time to process it; this happens whenever Emacs is waiting for | |
942 | keyboard input or for time to elapse. | |
943 | ||
944 | To make multiple terminal emulators, rename the buffer @samp{*term*} | |
945 | to something different using @kbd{M-x rename-uniquely}, | |
946 | just as with Shell mode. | |
947 | ||
948 | The file name used to load the subshell is determined | |
949 | the same way as for Shell mode. | |
950 | ||
951 | Unlike Shell mode, Term mode does not track the current directory | |
952 | by examining your input. Instead, if you use a programmable | |
953 | shell, you can have it tell Term what the current directory is. | |
954 | This is done automatically by @code{bash} version 1.15 and later. | |
955 | ||
956 | @node Term Mode | |
957 | @subsection Term Mode | |
958 | @cindex Term mode | |
959 | @cindex mode, Term | |
960 | ||
961 | Term uses Term mode, which has two input modes: | |
962 | In line mode, Term basically acts like Shell mode. @xref{Shell Mode}. | |
963 | In Char mode, each character is sent directly to the inferior subshell, | |
964 | except for the Term escape character, normally @kbd{C-c}. | |
965 | ||
966 | To switch between line and char mode, use these commands: | |
967 | @table @kbd | |
968 | @kindex C-c C-k @r{(Term mode)} | |
969 | @findex term-char-mode | |
970 | @item C-c C-k | |
971 | Switch to line mode. Do nothing if already in line mode. | |
972 | ||
973 | @kindex C-c C-j @r{(Term mode)} | |
974 | @findex term-line-mode | |
975 | @item C-c C-j | |
976 | Switch to char mode. Do nothing if already in char mode. | |
977 | @end table | |
978 | ||
979 | The following commands are only available in Char mode: | |
980 | @table @kbd | |
981 | @item C-c C-c | |
982 | Send a literal @key{C-c} to the sub-shell. | |
983 | ||
984 | @item C-c C-x | |
985 | A prefix command to access the global @key{C-x} commands conveniently. | |
986 | For example, @kbd{C-c C-x o} invokes the global binding of | |
987 | @kbd{C-x o}, which is normally @samp{other-window}. | |
988 | @end table | |
989 | ||
990 | @node Paging in Term | |
991 | @subsection Paging in the terminal emulator | |
992 | ||
993 | Term mode has a pager feature. When the pager is enabled, | |
994 | term mode will pause at the end of each screenful. | |
995 | ||
996 | @table @kbd | |
997 | @kindex C-c C-q @r{(Term mode)} | |
998 | @findex term-pager-toggle | |
999 | @item C-c C-q | |
1000 | Toggles the pager feature: Disables the pager if it is enabled, | |
1001 | and vice versa. This works in both line and char modes. | |
1002 | If the pager enabled, the mode-line contains the word @samp{page}. | |
1003 | @end table | |
1004 | ||
1005 | If the pager is enabled, and Term receives more than a screenful | |
1006 | of output since your last input, Term will enter More break mode. | |
1007 | This is indicated by @samp{**MORE**} in the mode-line. | |
1008 | Type a @kbd{Space} to display the next screenful of output. | |
1009 | Type @kbd{?} to see your other options. The interface is similar | |
1010 | to the Unix @code{more} program. | |
1011 | ||
6bf7aab6 DL |
1012 | @node Remote Host |
1013 | @subsection Remote Host Shell | |
1014 | @cindex remote host | |
1015 | @cindex connecting to remote host | |
1016 | @cindex Telnet | |
1017 | @cindex Rlogin | |
1018 | ||
3b65ce47 DL |
1019 | You can login to a remote computer, using whatever commands you |
1020 | would from a regular terminal (e.g.@: using the @code{telnet} or | |
1021 | @code{rlogin} commands), from a Term window. | |
1022 | ||
1023 | A program that asks you for a password will normally suppress | |
1024 | echoing of the password, so the password will not show up in the buffer. | |
1025 | This will happen just as if you were using a real terminal, if | |
1026 | the buffer is in char mode. If it is in line mode, the password | |
1027 | will be temporarily visible, but will be erased when you hit return. | |
1028 | (This happens automatically; there is no special password processing.) | |
1029 | ||
1030 | When you log in to a different machine, you need to specify the | |
1031 | type of terminal your using. Terminal types @samp{ansi} | |
1032 | or @samp{vt100} will work on most systems. | |
1033 | ||
1034 | @c If you are talking to a Bourne-compatible | |
60a96371 | 1035 | @c shell, and your system understands the @env{TERMCAP} variable, |
3b65ce47 DL |
1036 | @c you can use the command @kbd{M-x shell-send-termcap}, which |
1037 | @c sends a string specifying the terminal type and size. | |
1038 | @c (This command is also useful after the window has changed size.) | |
1039 | ||
1040 | @c You can of course run @samp{gdb} on that remote computer. One useful | |
1041 | @c trick: If you invoke gdb with the @code{--fullname} option, | |
1042 | @c it will send special commands to Emacs that will cause Emacs to | |
1043 | @c pop up the source files you're debugging. This will work | |
1044 | @c whether or not gdb is running on a different computer than Emacs, | |
1045 | @c as long as Emacs can access the source files specified by gdb. | |
1046 | ||
1047 | You cannot log into to a remove comuter using the Shell mode. | |
1048 | @c (This will change when Shell is re-written to use Term.) | |
1049 | Instead, Emacs provides two commands for logging in to another computer | |
6bf7aab6 DL |
1050 | and communicating with it through an Emacs buffer. |
1051 | ||
1052 | @table @kbd | |
1053 | @item M-x telnet @key{RET} @var{hostname} @key{RET} | |
1054 | Set up a Telnet connection to the computer named @var{hostname}. | |
1055 | @item M-x rlogin @key{RET} @var{hostname} @key{RET} | |
1056 | Set up an Rlogin connection to the computer named @var{hostname}. | |
1057 | @end table | |
1058 | ||
1059 | @findex telnet | |
1060 | Use @kbd{M-x telnet} to set up a Telnet connection to another | |
1061 | computer. (Telnet is the standard Internet protocol for remote login.) | |
1062 | It reads the host name of the other computer as an argument with the | |
1063 | minibuffer. Once the connection is established, talking to the other | |
1064 | computer works like talking to a subshell: you can edit input with the | |
1065 | usual Emacs commands, and send it a line at a time by typing @key{RET}. | |
1066 | The output is inserted in the Telnet buffer interspersed with the input. | |
1067 | ||
1068 | @findex rlogin | |
1069 | @vindex rlogin-explicit-args | |
1070 | Use @kbd{M-x rlogin} to set up an Rlogin connection. Rlogin is | |
1071 | another remote login communication protocol, essentially much like the | |
1072 | Telnet protocol but incompatible with it, and supported only by certain | |
1073 | systems. Rlogin's advantages are that you can arrange not to have to | |
1074 | give your user name and password when communicating between two machines | |
1075 | you frequently use, and that you can make an 8-bit-clean connection. | |
1076 | (To do that in Emacs, set @code{rlogin-explicit-args} to @code{("-8")} | |
1077 | before you run Rlogin.) | |
1078 | ||
1079 | @kbd{M-x rlogin} sets up the default file directory of the Emacs | |
1080 | buffer to access the remote host via FTP (@pxref{File Names}), and it | |
1081 | tracks the shell commands that change the current directory, just like | |
1082 | Shell mode. | |
1083 | ||
1084 | @findex rlogin-directory-tracking-mode | |
1085 | There are two ways of doing directory tracking in an Rlogin | |
1086 | buffer---either with remote directory names | |
1087 | @file{/@var{host}:@var{dir}/} or with local names (that works if the | |
1088 | ``remote'' machine shares file systems with your machine of origin). | |
1089 | You can use the command @code{rlogin-directory-tracking-mode} to switch | |
1090 | modes. No argument means use remote directory names, a positive | |
1091 | argument means use local names, and a negative argument means turn | |
1092 | off directory tracking. | |
1093 | ||
1094 | @node Emacs Server, Hardcopy, Shell, Top | |
1095 | @section Using Emacs as a Server | |
1096 | @pindex emacsclient | |
1097 | @cindex Emacs as a server | |
1098 | @cindex server, using Emacs as | |
60a96371 | 1099 | @cindex @env{EDITOR} environment variable |
6bf7aab6 DL |
1100 | |
1101 | Various programs such as @code{mail} can invoke your choice of editor | |
1102 | to edit a particular piece of text, such as a message that you are | |
1103 | sending. By convention, most of these programs use the environment | |
60a96371 GM |
1104 | variable @env{EDITOR} to specify which editor to run. If you set |
1105 | @env{EDITOR} to @samp{emacs}, they invoke Emacs---but in an | |
6bf7aab6 DL |
1106 | inconvenient fashion, by starting a new, separate Emacs process. This |
1107 | is inconvenient because it takes time and because the new Emacs process | |
1108 | doesn't share the buffers in the existing Emacs process. | |
1109 | ||
1110 | You can arrange to use your existing Emacs process as the editor for | |
1111 | programs like @code{mail} by using the Emacs client and Emacs server | |
1112 | programs. Here is how. | |
1113 | ||
60a96371 | 1114 | @cindex @env{TEXEDIT} environment variable |
6bf7aab6 DL |
1115 | First, the preparation. Within Emacs, call the function |
1116 | @code{server-start}. (Your @file{.emacs} file can do this automatically | |
1117 | if you add the expression @code{(server-start)} to it.) Then, outside | |
60a96371 | 1118 | Emacs, set the @env{EDITOR} environment variable to @samp{emacsclient}. |
6bf7aab6 DL |
1119 | (Note that some programs use a different environment variable; for |
1120 | example, to make @TeX{} use @samp{emacsclient}, you should set the | |
60a96371 | 1121 | @env{TEXEDIT} environment variable to @samp{emacsclient +%d %s}.) |
6bf7aab6 DL |
1122 | |
1123 | @kindex C-x # | |
1124 | @findex server-edit | |
60a96371 | 1125 | Then, whenever any program invokes your specified @env{EDITOR} |
6bf7aab6 DL |
1126 | program, the effect is to send a message to your principal Emacs telling |
1127 | it to visit a file. (That's what the program @code{emacsclient} does.) | |
1128 | Emacs displays the buffer immediately and you can immediately begin | |
1129 | editing it. | |
1130 | ||
1131 | When you've finished editing that buffer, type @kbd{C-x #} | |
1132 | (@code{server-edit}). This saves the file and sends a message back to | |
1133 | the @code{emacsclient} program telling it to exit. The programs that | |
60a96371 | 1134 | use @env{EDITOR} wait for the ``editor'' (actually, @code{emacsclient}) |
6bf7aab6 DL |
1135 | to exit. @kbd{C-x #} also checks for other pending external requests |
1136 | to edit various files, and selects the next such file. | |
1137 | ||
1138 | You can switch to a server buffer manually if you wish; you don't have | |
1139 | to arrive at it with @kbd{C-x #}. But @kbd{C-x #} is the only way to | |
1140 | say that you are ``finished'' with one. | |
1141 | ||
1142 | @vindex server-window | |
1143 | If you set the variable @code{server-window} to a window or a frame, | |
1144 | @kbd{C-x #} displays the server buffer in that window or in that frame. | |
1145 | ||
1146 | While @code{mail} or another application is waiting for | |
1147 | @code{emacsclient} to finish, @code{emacsclient} does not read terminal | |
1148 | input. So the terminal that @code{mail} was using is effectively | |
1149 | blocked for the duration. In order to edit with your principal Emacs, | |
1150 | you need to be able to use it without using that terminal. There are | |
1151 | two ways to do this: | |
1152 | ||
1153 | @itemize @bullet | |
1154 | @item | |
1155 | Using a window system, run @code{mail} and the principal Emacs in two | |
1156 | separate windows. While @code{mail} is waiting for @code{emacsclient}, | |
1157 | the window where it was running is blocked, but you can use Emacs by | |
1158 | switching windows. | |
1159 | ||
1160 | @item | |
1161 | Use Shell mode in Emacs to run the other program such as @code{mail}; | |
1162 | then, @code{emacsclient} blocks only the subshell under Emacs, and you | |
1163 | can still use Emacs to edit the file. | |
1164 | @end itemize | |
1165 | ||
1166 | @vindex server-temp-file-regexp | |
1167 | Some programs write temporary files for you to edit. After you edit | |
1168 | the temporary file, the program reads it back and deletes it. If the | |
1169 | Emacs server is later asked to edit the same file name, it should assume | |
1170 | this has nothing to do with the previous occasion for that file name. | |
1171 | The server accomplishes this by killing the temporary file's buffer when | |
1172 | you finish with the file. Use the variable | |
1173 | @code{server-temp-file-regexp} to specify which files are temporary in | |
1174 | this sense; its value should be a regular expression that matches file | |
1175 | names that are temporary. | |
1176 | ||
1177 | If you run @code{emacsclient} with the option @samp{--no-wait}, it | |
1178 | returns immediately without waiting for you to ``finish'' the buffer in | |
1179 | Emacs. | |
1180 | ||
6182798c GM |
1181 | If you have forgotten to start Emacs, then the option |
1182 | @samp{--alternate-editor=@var{command}} may be useful. It specifies a | |
1183 | command to run if @code{emacsclient} fails to contact Emacs. For | |
1184 | example, the following setting for the @var{EDITOR} environment variable | |
1185 | will always give an editor, even if Emacs is not running. | |
1186 | ||
1187 | @example | |
1188 | EDITOR="emacsclient --alternate-editor vi +%d %s" | |
1189 | @end example | |
1190 | ||
1191 | The environment variable @var{ALTERNATE_EDITOR} has the same effect, but | |
1192 | the value of the @samp{--alternate-editor} takes precedence. | |
1193 | ||
6bf7aab6 DL |
1194 | @menu |
1195 | * Invoking emacsclient:: | |
1196 | @end menu | |
1197 | ||
1198 | @node Invoking emacsclient,, Emacs Server, Emacs Server | |
1199 | @section Invoking @code{emacsclient} | |
1200 | ||
1201 | To run the @code{emacsclient} program, specify file names as arguments, | |
1202 | and optionally line numbers as well. Do it like this: | |
1203 | ||
1204 | @example | |
1205 | emacsclient @r{@{}@r{[}+@var{line}@r{]} @var{filename}@r{@}}@dots{} | |
1206 | @end example | |
1207 | ||
1208 | This tells Emacs to visit each of the specified files; if you specify a | |
1209 | line number for a certain file, Emacs moves to that line in the file. | |
1210 | ||
1211 | Ordinarily, @code{emacsclient} does not return until you use the | |
1212 | @kbd{C-x #} command on each of these buffers. When that happens, Emacs | |
1213 | sends a message to the @code{emacsclient} program telling it to return. | |
1214 | ||
1215 | But if you use the option @samp{-n} or @samp{--no-wait} when running | |
1216 | @code{emacsclient}, then it returns immediately. (You can take as long | |
1217 | as you like to edit the files in Emacs.) | |
1218 | ||
1219 | ||
3b65ce47 | 1220 | @node Hardcopy, PostScript, Emacs Server, Top |
6bf7aab6 DL |
1221 | @section Hardcopy Output |
1222 | @cindex hardcopy | |
1223 | ||
1224 | The Emacs commands for making hardcopy let you print either an entire | |
1225 | buffer or just part of one, either with or without page headers. | |
1226 | See also the hardcopy commands of Dired (@pxref{Misc File Ops}) | |
1227 | and the diary (@pxref{Diary Commands}). | |
1228 | ||
1229 | @table @kbd | |
1230 | @item M-x print-buffer | |
1231 | Print hardcopy of current buffer with page headings containing the file | |
1232 | name and page number. | |
1233 | @item M-x lpr-buffer | |
1234 | Print hardcopy of current buffer without page headings. | |
1235 | @item M-x print-region | |
1236 | Like @code{print-buffer} but print only the current region. | |
1237 | @item M-x lpr-region | |
1238 | Like @code{lpr-buffer} but print only the current region. | |
1239 | @end table | |
1240 | ||
1241 | @findex print-buffer | |
1242 | @findex print-region | |
1243 | @findex lpr-buffer | |
1244 | @findex lpr-region | |
1245 | @vindex lpr-switches | |
1246 | The hardcopy commands (aside from the Postscript commands) pass extra | |
1247 | switches to the @code{lpr} program based on the value of the variable | |
1248 | @code{lpr-switches}. Its value should be a list of strings, each string | |
1249 | an option starting with @samp{-}. For example, to specify a line width | |
1250 | of 80 columns for all the printing you do in Emacs, set | |
1251 | @code{lpr-switches} like this: | |
1252 | ||
1253 | @example | |
1254 | (setq lpr-switches '("-w80")) | |
1255 | @end example | |
1256 | ||
1257 | @vindex printer-name | |
1258 | You can specify the printer to use by setting the variable | |
1259 | @code{printer-name}. | |
1260 | ||
1261 | @vindex lpr-headers-switches | |
1262 | @vindex lpr-commands | |
1263 | @vindex lpr-add-switches | |
1264 | The variable @code{lpr-command} specifies the name of the printer | |
1265 | program to run; the default value depends on your operating system type. | |
1266 | On most systems, the default is @code{"lpr"}. The variable | |
1267 | @code{lpr-headers-switches} similarly specifies the extra switches to | |
1268 | use to make page headers. The variable @code{lpr-add-switches} controls | |
1269 | whether to supply @samp{-T} and @samp{-J} options (suitable for | |
1270 | @code{lpr}) to the printer program: @code{nil} means don't add them. | |
1271 | @code{lpr-add-switches} should be @code{nil} if your printer program is | |
1272 | not compatible with @code{lpr}. | |
1273 | ||
3b65ce47 DL |
1274 | @node PostScript, PostScript Variables, Hardcopy, Top |
1275 | @section PostScript Hardcopy | |
6bf7aab6 | 1276 | |
3b65ce47 | 1277 | These commands convert buffer contents to PostScript, |
6bf7aab6 DL |
1278 | either printing it or leaving it in another Emacs buffer. |
1279 | ||
1280 | @table @kbd | |
1281 | @item M-x ps-print-buffer | |
3b65ce47 | 1282 | Print hardcopy of the current buffer in PostScript form. |
6bf7aab6 | 1283 | @item M-x ps-print-region |
3b65ce47 | 1284 | Print hardcopy of the current region in PostScript form. |
6bf7aab6 | 1285 | @item M-x ps-print-buffer-with-faces |
3b65ce47 DL |
1286 | Print hardcopy of the current buffer in PostScript form, showing the |
1287 | faces used in the text by means of PostScript features. | |
6bf7aab6 | 1288 | @item M-x ps-print-region-with-faces |
3b65ce47 | 1289 | Print hardcopy of the current region in PostScript form, showing the |
6bf7aab6 DL |
1290 | faces used in the text. |
1291 | @item M-x ps-spool-buffer | |
3b65ce47 | 1292 | Generate PostScript for the current buffer text. |
6bf7aab6 | 1293 | @item M-x ps-spool-region |
3b65ce47 | 1294 | Generate PostScript for the current region. |
6bf7aab6 | 1295 | @item M-x ps-spool-buffer-with-faces |
3b65ce47 | 1296 | Generate PostScript for the current buffer, showing the faces used. |
6bf7aab6 | 1297 | @item M-x ps-spool-region-with-faces |
3b65ce47 DL |
1298 | Generate PostScript for the current region, showing the faces used. |
1299 | @item M-x handwrite | |
1300 | Generates/prints PostScript for the current buffer as if handwritten. | |
6bf7aab6 DL |
1301 | @end table |
1302 | ||
1303 | @findex ps-print-region | |
1304 | @findex ps-print-buffer | |
1305 | @findex ps-print-region-with-faces | |
1306 | @findex ps-print-buffer-with-faces | |
3b65ce47 DL |
1307 | The PostScript commands, @code{ps-print-buffer} and |
1308 | @code{ps-print-region}, print buffer contents in PostScript form. One | |
6bf7aab6 DL |
1309 | command prints the entire buffer; the other, just the region. The |
1310 | corresponding @samp{-with-faces} commands, | |
1311 | @code{ps-print-buffer-with-faces} and @code{ps-print-region-with-faces}, | |
3b65ce47 | 1312 | use PostScript features to show the faces (fonts and colors) in the text |
6bf7aab6 DL |
1313 | properties of the text being printed. |
1314 | ||
1315 | If you are using a color display, you can print a buffer of program | |
1316 | code with color highlighting by turning on Font-Lock mode in that | |
1317 | buffer, and using @code{ps-print-buffer-with-faces}. | |
1318 | ||
1319 | @findex ps-spool-region | |
1320 | @findex ps-spool-buffer | |
1321 | @findex ps-spool-region-with-faces | |
1322 | @findex ps-spool-buffer-with-faces | |
1323 | The commands whose names have @samp{spool} instead of @samp{print} | |
3b65ce47 | 1324 | generate the PostScript output in an Emacs buffer instead of sending |
6bf7aab6 DL |
1325 | it to the printer. |
1326 | ||
3b65ce47 DL |
1327 | @findex handwrite |
1328 | @cindex handwriting | |
1329 | @kbd{M-x handwrite} is more frivolous. It generates a PostScript | |
1330 | rendition of the current buffer as a cursive handwritten document. It | |
1331 | can be customized in group @code{handwrite}. | |
1332 | ||
6bf7aab6 DL |
1333 | @ifinfo |
1334 | The following section describes variables for customizing these commands. | |
1335 | @end ifinfo | |
1336 | ||
3b65ce47 DL |
1337 | @node PostScript Variables, Sorting, PostScript, Top |
1338 | @section Variables for PostScript Hardcopy | |
6bf7aab6 DL |
1339 | |
1340 | @vindex ps-lpr-command | |
1341 | @vindex ps-lpr-switches | |
1342 | @vindex ps-printer-name | |
3b65ce47 | 1343 | All the PostScript hardcopy commands use the variables |
6bf7aab6 DL |
1344 | @code{ps-lpr-command} and @code{ps-lpr-switches} to specify how to print |
1345 | the output. @code{ps-lpr-command} specifies the command name to run, | |
1346 | @code{ps-lpr-switches} specifies command line options to use, and | |
1347 | @code{ps-printer-name} specifies the printer. If you don't set the | |
1348 | first two variables yourself, they take their initial values from | |
1349 | @code{lpr-command} and @code{lpr-switches}. If @code{ps-printer-name} | |
1350 | is @code{nil}, @code{printer-name} is used. | |
1351 | ||
1352 | @vindex ps-print-header | |
1353 | @vindex ps-print-color-p | |
1354 | The variable @code{ps-print-header} controls whether these commands | |
1355 | add header lines to each page---set it to @code{nil} to turn headers | |
1356 | off. You can turn off color processing by setting | |
1357 | @code{ps-print-color-p} to @code{nil}. | |
1358 | ||
1359 | @vindex ps-paper-type | |
1360 | @vindex ps-page-dimensions-database | |
1361 | The variable @code{ps-paper-type} specifies which size of paper to | |
1362 | format for; legitimate values include @code{a4}, @code{a3}, | |
1363 | @code{a4small}, @code{b4}, @code{b5}, @code{executive}, @code{ledger}, | |
1364 | @code{legal}, @code{letter}, @code{letter-small}, @code{statement}, | |
1365 | @code{tabloid}. The default is @code{letter}. You can define | |
1366 | additional paper sizes by changing the variable | |
1367 | @code{ps-page-dimensions-database}. | |
1368 | ||
1369 | @vindex ps-landscape-mode | |
1370 | The variable @code{ps-landscape-mode} specifies the orientation of | |
1371 | printing on the page. The default is @code{nil}, which stands for | |
1372 | ``portrait'' mode. Any non-@code{nil} value specifies ``landscape'' | |
1373 | mode. | |
1374 | ||
1375 | @vindex ps-number-of-columns | |
1376 | The variable @code{ps-number-of-columns} specifies the number of | |
1377 | columns; it takes effect in both landscape and portrait mode. The | |
1378 | default is 1. | |
1379 | ||
1380 | @vindex ps-font-family | |
1381 | @vindex ps-font-size | |
1382 | @vindex ps-font-info-database | |
1383 | The variable @code{ps-font-family} specifies which font family to use | |
1384 | for printing ordinary text. Legitimate values include @code{Courier}, | |
1385 | @code{Helvetica}, @code{NewCenturySchlbk}, @code{Palatino} and | |
1386 | @code{Times}. The variable @code{ps-font-size} specifies the size of | |
1387 | the font for ordinary text. It defaults to 8.5 points. | |
1388 | ||
1389 | Many other customization variables for these commands are defined and | |
1390 | described in the Lisp file @file{ps-print.el}. | |
1391 | ||
3b65ce47 | 1392 | @node Sorting, Narrowing, PostScript Variables, Top |
6bf7aab6 DL |
1393 | @section Sorting Text |
1394 | @cindex sorting | |
1395 | ||
1396 | Emacs provides several commands for sorting text in the buffer. All | |
1397 | operate on the contents of the region (the text between point and the | |
1398 | mark). They divide the text of the region into many @dfn{sort records}, | |
1399 | identify a @dfn{sort key} for each record, and then reorder the records | |
1400 | into the order determined by the sort keys. The records are ordered so | |
1401 | that their keys are in alphabetical order, or, for numeric sorting, in | |
1402 | numeric order. In alphabetic sorting, all upper-case letters `A' through | |
1403 | `Z' come before lower-case `a', in accord with the ASCII character | |
1404 | sequence. | |
1405 | ||
1406 | The various sort commands differ in how they divide the text into sort | |
1407 | records and in which part of each record is used as the sort key. Most of | |
1408 | the commands make each line a separate sort record, but some commands use | |
1409 | paragraphs or pages as sort records. Most of the sort commands use each | |
1410 | entire sort record as its own sort key, but some use only a portion of the | |
1411 | record as the sort key. | |
1412 | ||
1413 | @findex sort-lines | |
1414 | @findex sort-paragraphs | |
1415 | @findex sort-pages | |
1416 | @findex sort-fields | |
1417 | @findex sort-numeric-fields | |
efd68b8a | 1418 | @vindex sort-numeric-base |
6bf7aab6 DL |
1419 | @table @kbd |
1420 | @item M-x sort-lines | |
1421 | Divide the region into lines, and sort by comparing the entire | |
1422 | text of a line. A numeric argument means sort into descending order. | |
1423 | ||
1424 | @item M-x sort-paragraphs | |
1425 | Divide the region into paragraphs, and sort by comparing the entire | |
1426 | text of a paragraph (except for leading blank lines). A numeric | |
1427 | argument means sort into descending order. | |
1428 | ||
1429 | @item M-x sort-pages | |
1430 | Divide the region into pages, and sort by comparing the entire | |
1431 | text of a page (except for leading blank lines). A numeric | |
1432 | argument means sort into descending order. | |
1433 | ||
1434 | @item M-x sort-fields | |
1435 | Divide the region into lines, and sort by comparing the contents of | |
1436 | one field in each line. Fields are defined as separated by | |
1437 | whitespace, so the first run of consecutive non-whitespace characters | |
1438 | in a line constitutes field 1, the second such run constitutes field | |
1439 | 2, etc. | |
1440 | ||
1441 | Specify which field to sort by with a numeric argument: 1 to sort by | |
1442 | field 1, etc. A negative argument means count fields from the right | |
1443 | instead of from the left; thus, minus 1 means sort by the last field. | |
1444 | If several lines have identical contents in the field being sorted, they | |
1445 | keep same relative order that they had in the original buffer. | |
1446 | ||
1447 | @item M-x sort-numeric-fields | |
1448 | Like @kbd{M-x sort-fields} except the specified field is converted | |
1449 | to an integer for each line, and the numbers are compared. @samp{10} | |
1450 | comes before @samp{2} when considered as text, but after it when | |
efd68b8a GM |
1451 | considered as a number. By default, numbers are interpreted according |
1452 | to @code{sort-numeric-base}, but numbers beginning with @samp{0x} or | |
1453 | @samp{0} are interpreted as hexadecimal and octal, respectively. | |
6bf7aab6 DL |
1454 | |
1455 | @item M-x sort-columns | |
1456 | Like @kbd{M-x sort-fields} except that the text within each line | |
1457 | used for comparison comes from a fixed range of columns. See below | |
1458 | for an explanation. | |
1459 | ||
1460 | @item M-x reverse-region | |
1461 | Reverse the order of the lines in the region. This is useful for | |
1462 | sorting into descending order by fields or columns, since those sort | |
1463 | commands do not have a feature for doing that. | |
1464 | @end table | |
1465 | ||
1466 | For example, if the buffer contains this: | |
1467 | ||
1468 | @smallexample | |
1469 | On systems where clash detection (locking of files being edited) is | |
1470 | implemented, Emacs also checks the first time you modify a buffer | |
1471 | whether the file has changed on disk since it was last visited or | |
1472 | saved. If it has, you are asked to confirm that you want to change | |
1473 | the buffer. | |
1474 | @end smallexample | |
1475 | ||
1476 | @noindent | |
1477 | applying @kbd{M-x sort-lines} to the entire buffer produces this: | |
1478 | ||
1479 | @smallexample | |
1480 | On systems where clash detection (locking of files being edited) is | |
1481 | implemented, Emacs also checks the first time you modify a buffer | |
1482 | saved. If it has, you are asked to confirm that you want to change | |
1483 | the buffer. | |
1484 | whether the file has changed on disk since it was last visited or | |
1485 | @end smallexample | |
1486 | ||
1487 | @noindent | |
1488 | where the upper-case @samp{O} sorts before all lower-case letters. If | |
1489 | you use @kbd{C-u 2 M-x sort-fields} instead, you get this: | |
1490 | ||
1491 | @smallexample | |
1492 | implemented, Emacs also checks the first time you modify a buffer | |
1493 | saved. If it has, you are asked to confirm that you want to change | |
1494 | the buffer. | |
1495 | On systems where clash detection (locking of files being edited) is | |
1496 | whether the file has changed on disk since it was last visited or | |
1497 | @end smallexample | |
1498 | ||
1499 | @noindent | |
1500 | where the sort keys were @samp{Emacs}, @samp{If}, @samp{buffer}, | |
1501 | @samp{systems} and @samp{the}. | |
1502 | ||
1503 | @findex sort-columns | |
1504 | @kbd{M-x sort-columns} requires more explanation. You specify the | |
1505 | columns by putting point at one of the columns and the mark at the other | |
1506 | column. Because this means you cannot put point or the mark at the | |
1507 | beginning of the first line of the text you want to sort, this command | |
1508 | uses an unusual definition of `region': all of the line point is in is | |
1509 | considered part of the region, and so is all of the line the mark is in, | |
1510 | as well as all the lines in between. | |
1511 | ||
1512 | For example, to sort a table by information found in columns 10 to 15, | |
1513 | you could put the mark on column 10 in the first line of the table, and | |
1514 | point on column 15 in the last line of the table, and then run | |
1515 | @code{sort-columns}. Equivalently, you could run it with the mark on | |
1516 | column 15 in the first line and point on column 10 in the last line. | |
1517 | ||
1518 | This can be thought of as sorting the rectangle specified by point and | |
1519 | the mark, except that the text on each line to the left or right of the | |
1520 | rectangle moves along with the text inside the rectangle. | |
1521 | @xref{Rectangles}. | |
1522 | ||
1523 | @vindex sort-fold-case | |
1524 | Many of the sort commands ignore case differences when comparing, if | |
1525 | @code{sort-fold-case} is non-@code{nil}. | |
1526 | ||
1527 | @node Narrowing, Two-Column, Sorting, Top | |
1528 | @section Narrowing | |
1529 | @cindex widening | |
1530 | @cindex restriction | |
1531 | @cindex narrowing | |
1532 | @cindex accessible portion | |
1533 | ||
1534 | @dfn{Narrowing} means focusing in on some portion of the buffer, | |
1535 | making the rest temporarily inaccessible. The portion which you can | |
1536 | still get to is called the @dfn{accessible portion}. Canceling the | |
1537 | narrowing, which makes the entire buffer once again accessible, is | |
1538 | called @dfn{widening}. The amount of narrowing in effect in a buffer at | |
1539 | any time is called the buffer's @dfn{restriction}. | |
1540 | ||
1541 | Narrowing can make it easier to concentrate on a single subroutine or | |
1542 | paragraph by eliminating clutter. It can also be used to restrict the | |
1543 | range of operation of a replace command or repeating keyboard macro. | |
1544 | ||
1545 | @c WideCommands | |
1546 | @table @kbd | |
1547 | @item C-x n n | |
1548 | Narrow down to between point and mark (@code{narrow-to-region}). | |
1549 | @item C-x n w | |
1550 | Widen to make the entire buffer accessible again (@code{widen}). | |
1551 | @item C-x n p | |
1552 | Narrow down to the current page (@code{narrow-to-page}). | |
1553 | @item C-x n d | |
1554 | Narrow down to the current defun (@code{narrow-to-defun}). | |
1555 | @end table | |
1556 | ||
1557 | When you have narrowed down to a part of the buffer, that part appears | |
1558 | to be all there is. You can't see the rest, you can't move into it | |
1559 | (motion commands won't go outside the accessible part), you can't change | |
1560 | it in any way. However, it is not gone, and if you save the file all | |
1561 | the inaccessible text will be saved. The word @samp{Narrow} appears in | |
1562 | the mode line whenever narrowing is in effect. | |
1563 | ||
1564 | @kindex C-x n n | |
1565 | @findex narrow-to-region | |
1566 | The primary narrowing command is @kbd{C-x n n} (@code{narrow-to-region}). | |
1567 | It sets the current buffer's restrictions so that the text in the current | |
1568 | region remains accessible but all text before the region or after the region | |
1569 | is inaccessible. Point and mark do not change. | |
1570 | ||
1571 | @kindex C-x n p | |
1572 | @findex narrow-to-page | |
1573 | @kindex C-x n d | |
1574 | @findex narrow-to-defun | |
1575 | Alternatively, use @kbd{C-x n p} (@code{narrow-to-page}) to narrow | |
1576 | down to the current page. @xref{Pages}, for the definition of a page. | |
1577 | @kbd{C-x n d} (@code{narrow-to-defun}) narrows down to the defun | |
1578 | containing point (@pxref{Defuns}). | |
1579 | ||
1580 | @kindex C-x n w | |
1581 | @findex widen | |
1582 | The way to cancel narrowing is to widen with @kbd{C-x n w} | |
1583 | (@code{widen}). This makes all text in the buffer accessible again. | |
1584 | ||
1585 | You can get information on what part of the buffer you are narrowed down | |
1586 | to using the @kbd{C-x =} command. @xref{Position Info}. | |
1587 | ||
1588 | Because narrowing can easily confuse users who do not understand it, | |
1589 | @code{narrow-to-region} is normally a disabled command. Attempting to use | |
1590 | this command asks for confirmation and gives you the option of enabling it; | |
1591 | if you enable the command, confirmation will no longer be required for | |
1592 | it. @xref{Disabling}. | |
1593 | ||
1594 | @node Two-Column, Editing Binary Files, Narrowing, Top | |
1595 | @section Two-Column Editing | |
1596 | @cindex two-column editing | |
1597 | @cindex splitting columns | |
1598 | @cindex columns, splitting | |
1599 | ||
1600 | Two-column mode lets you conveniently edit two side-by-side columns of | |
1601 | text. It uses two side-by-side windows, each showing its own | |
1602 | buffer. | |
1603 | ||
1604 | There are three ways to enter two-column mode: | |
1605 | ||
1606 | @table @asis | |
1607 | @item @kbd{@key{F2} 2} or @kbd{C-x 6 2} | |
1608 | @kindex F2 2 | |
1609 | @kindex C-x 6 2 | |
1610 | @findex 2C-two-columns | |
1611 | Enter two-column mode with the current buffer on the left, and on the | |
1612 | right, a buffer whose name is based on the current buffer's name | |
1613 | (@code{2C-two-columns}). If the right-hand buffer doesn't already | |
1614 | exist, it starts out empty; the current buffer's contents are not | |
1615 | changed. | |
1616 | ||
1617 | This command is appropriate when the current buffer is empty or contains | |
1618 | just one column and you want to add another column. | |
1619 | ||
1620 | @item @kbd{@key{F2} s} or @kbd{C-x 6 s} | |
1621 | @kindex F2 s | |
1622 | @kindex C-x 6 s | |
1623 | @findex 2C-split | |
1624 | Split the current buffer, which contains two-column text, into two | |
1625 | buffers, and display them side by side (@code{2C-split}). The current | |
1626 | buffer becomes the left-hand buffer, but the text in the right-hand | |
1627 | column is moved into the right-hand buffer. The current column | |
1628 | specifies the split point. Splitting starts with the current line and | |
1629 | continues to the end of the buffer. | |
1630 | ||
1631 | This command is appropriate when you have a buffer that already contains | |
1632 | two-column text, and you wish to separate the columns temporarily. | |
1633 | ||
1634 | @item @kbd{@key{F2} b @var{buffer} @key{RET}} | |
1635 | @itemx @kbd{C-x 6 b @var{buffer} @key{RET}} | |
1636 | @kindex F2 b | |
1637 | @kindex C-x 6 b | |
1638 | @findex 2C-associate-buffer | |
1639 | Enter two-column mode using the current buffer as the left-hand buffer, | |
1640 | and using buffer @var{buffer} as the right-hand buffer | |
1641 | (@code{2C-associate-buffer}). | |
1642 | @end table | |
1643 | ||
1644 | @kbd{@key{F2} s} or @kbd{C-x 6 s} looks for a column separator, which | |
1645 | is a string that appears on each line between the two columns. You can | |
1646 | specify the width of the separator with a numeric argument to | |
1647 | @kbd{@key{F2} s}; that many characters, before point, constitute the | |
1648 | separator string. By default, the width is 1, so the column separator | |
1649 | is the character before point. | |
1650 | ||
1651 | When a line has the separator at the proper place, @kbd{@key{F2} s} | |
1652 | puts the text after the separator into the right-hand buffer, and | |
1653 | deletes the separator. Lines that don't have the column separator at | |
1654 | the proper place remain unsplit; they stay in the left-hand buffer, and | |
1655 | the right-hand buffer gets an empty line to correspond. (This is the | |
1656 | way to write a line that ``spans both columns while in two-column | |
1657 | mode'': write it in the left-hand buffer, and put an empty line in the | |
1658 | right-hand buffer.) | |
1659 | ||
1660 | @kindex F2 RET | |
1661 | @kindex C-x 6 RET | |
1662 | @findex 2C-newline | |
1663 | The command @kbd{C-x 6 @key{RET}} or @kbd{@key{F2} @key{RET}} | |
1664 | (@code{2C-newline}) inserts a newline in each of the two buffers at | |
1665 | corresponding positions. This is the easiest way to add a new line to | |
1666 | the two-column text while editing it in split buffers. | |
1667 | ||
1668 | @kindex F2 1 | |
1669 | @kindex C-x 6 1 | |
1670 | @findex 2C-merge | |
1671 | When you have edited both buffers as you wish, merge them with | |
1672 | @kbd{@key{F2} 1} or @kbd{C-x 6 1} (@code{2C-merge}). This copies the | |
1673 | text from the right-hand buffer as a second column in the other buffer. | |
1674 | To go back to two-column editing, use @kbd{@key{F2} s}. | |
1675 | ||
1676 | @kindex F2 d | |
1677 | @kindex C-x 6 d | |
1678 | @findex 2C-dissociate | |
1679 | Use @kbd{@key{F2} d} or @kbd{C-x 6 d} to dissociate the two buffers, | |
1680 | leaving each as it stands (@code{2C-dissociate}). If the other buffer, | |
1681 | the one not current when you type @kbd{@key{F2} d}, is empty, | |
1682 | @kbd{@key{F2} d} kills it. | |
1683 | ||
1684 | @node Editing Binary Files, Saving Emacs Sessions, Two-Column, Top | |
1685 | @section Editing Binary Files | |
1686 | ||
1687 | @cindex Hexl mode | |
1688 | @cindex mode, Hexl | |
1689 | @cindex editing binary files | |
1690 | There is a special major mode for editing binary files: Hexl mode. To | |
1691 | use it, use @kbd{M-x hexl-find-file} instead of @kbd{C-x C-f} to visit | |
1692 | the file. This command converts the file's contents to hexadecimal and | |
1693 | lets you edit the translation. When you save the file, it is converted | |
1694 | automatically back to binary. | |
1695 | ||
1696 | You can also use @kbd{M-x hexl-mode} to translate an existing buffer | |
1697 | into hex. This is useful if you visit a file normally and then discover | |
1698 | it is a binary file. | |
1699 | ||
1700 | Ordinary text characters overwrite in Hexl mode. This is to reduce | |
1701 | the risk of accidentally spoiling the alignment of data in the file. | |
1702 | There are special commands for insertion. Here is a list of the | |
1703 | commands of Hexl mode: | |
1704 | ||
1705 | @c I don't think individual index entries for these commands are useful--RMS. | |
1706 | @table @kbd | |
1707 | @item C-M-d | |
1708 | Insert a byte with a code typed in decimal. | |
1709 | ||
1710 | @item C-M-o | |
1711 | Insert a byte with a code typed in octal. | |
1712 | ||
1713 | @item C-M-x | |
1714 | Insert a byte with a code typed in hex. | |
1715 | ||
1716 | @item C-x [ | |
1717 | Move to the beginning of a 1k-byte ``page.'' | |
1718 | ||
1719 | @item C-x ] | |
1720 | Move to the end of a 1k-byte ``page.'' | |
1721 | ||
1722 | @item M-g | |
1723 | Move to an address specified in hex. | |
1724 | ||
1725 | @item M-j | |
1726 | Move to an address specified in decimal. | |
1727 | ||
1728 | @item C-c C-c | |
1729 | Leave Hexl mode, going back to the major mode this buffer had before you | |
1730 | invoked @code{hexl-mode}. | |
1731 | @end table | |
1732 | ||
1733 | @node Saving Emacs Sessions, Recursive Edit, Editing Binary Files, Top | |
1734 | @section Saving Emacs Sessions | |
1735 | @cindex saving sessions | |
1736 | @cindex desktop | |
1737 | ||
1738 | You can use the Desktop library to save the state of Emacs from one | |
1739 | session to another. Saving the state means that Emacs starts up with | |
1740 | the same set of buffers, major modes, buffer positions, and so on that | |
1741 | the previous Emacs session had. | |
1742 | ||
1743 | @vindex desktop-enable | |
1744 | To use Desktop, you should use the Customization buffer (@pxref{Easy | |
1745 | Customization}) to set @code{desktop-enable} to a non-@code{nil} value, | |
1746 | or add these lines at the end of your @file{.emacs} file: | |
1747 | ||
1748 | @example | |
1749 | (desktop-load-default) | |
1750 | (desktop-read) | |
1751 | @end example | |
1752 | ||
1753 | @noindent | |
1754 | @findex desktop-save | |
1755 | The first time you save the state of the Emacs session, you must do it | |
1756 | manually, with the command @kbd{M-x desktop-save}. Once you have done | |
1757 | that, exiting Emacs will save the state again---not only the present | |
1758 | Emacs session, but also subsequent sessions. You can also save the | |
1759 | state at any time, without exiting Emacs, by typing @kbd{M-x | |
1760 | desktop-save} again. | |
1761 | ||
1762 | In order for Emacs to recover the state from a previous session, you | |
1763 | must start it with the same current directory as you used when you | |
1764 | started the previous session. This is because @code{desktop-read} looks | |
1765 | in the current directory for the file to read. This means that you can | |
1766 | have separate saved sessions in different directories; the directory in | |
1767 | which you start Emacs will control which saved session to use. | |
1768 | ||
1769 | @vindex desktop-files-not-to-save | |
1770 | The variable @code{desktop-files-not-to-save} controls which files are | |
1771 | excluded from state saving. Its value is a regular expression that | |
1772 | matches the files to exclude. By default, remote (ftp-accessed) files | |
1773 | are excluded; this is because visiting them again in the subsequent | |
1774 | session would be slow. If you want to include these files in state | |
1775 | saving, set @code{desktop-files-not-to-save} to @code{"^$"}. | |
1776 | @xref{Remote Files}. | |
1777 | ||
17a4f5ec DL |
1778 | @vindex save-place |
1779 | @cindex Saveplace | |
1780 | @findex toggle-save-place | |
1781 | There is a simpler mechanism provided by Saveplace library which records | |
1782 | your position in each file when you kill its buffer (or kill Emacs), and | |
1783 | jumps to the same position when you visit the file again (even in | |
1784 | another Emacs session). Use @key{M-x toggle-save-place} to turn on | |
1785 | place-saving in a given file. Customize the option @code{save-place} to | |
1786 | turn it on for all files in each session. | |
1787 | ||
6bf7aab6 DL |
1788 | @node Recursive Edit, Emulation, Saving Emacs Sessions, Top |
1789 | @section Recursive Editing Levels | |
1790 | @cindex recursive editing level | |
1791 | @cindex editing level, recursive | |
1792 | ||
1793 | A @dfn{recursive edit} is a situation in which you are using Emacs | |
1794 | commands to perform arbitrary editing while in the middle of another | |
1795 | Emacs command. For example, when you type @kbd{C-r} inside of a | |
1796 | @code{query-replace}, you enter a recursive edit in which you can change | |
1797 | the current buffer. On exiting from the recursive edit, you go back to | |
1798 | the @code{query-replace}. | |
1799 | ||
1800 | @kindex C-M-c | |
1801 | @findex exit-recursive-edit | |
1802 | @cindex exiting recursive edit | |
1803 | @dfn{Exiting} the recursive edit means returning to the unfinished | |
1804 | command, which continues execution. The command to exit is @kbd{C-M-c} | |
1805 | (@code{exit-recursive-edit}). | |
1806 | ||
1807 | You can also @dfn{abort} the recursive edit. This is like exiting, | |
1808 | but also quits the unfinished command immediately. Use the command | |
1809 | @kbd{C-]} (@code{abort-recursive-edit}) to do this. @xref{Quitting}. | |
1810 | ||
1811 | The mode line shows you when you are in a recursive edit by displaying | |
1812 | square brackets around the parentheses that always surround the major and | |
1813 | minor mode names. Every window's mode line shows this, in the same way, | |
1814 | since being in a recursive edit is true of Emacs as a whole rather than | |
1815 | any particular window or buffer. | |
1816 | ||
1817 | It is possible to be in recursive edits within recursive edits. For | |
1818 | example, after typing @kbd{C-r} in a @code{query-replace}, you may type a | |
1819 | command that enters the debugger. This begins a recursive editing level | |
1820 | for the debugger, within the recursive editing level for @kbd{C-r}. | |
1821 | Mode lines display a pair of square brackets for each recursive editing | |
1822 | level currently in progress. | |
1823 | ||
1824 | Exiting the inner recursive edit (such as, with the debugger @kbd{c} | |
1825 | command) resumes the command running in the next level up. When that | |
1826 | command finishes, you can then use @kbd{C-M-c} to exit another recursive | |
1827 | editing level, and so on. Exiting applies to the innermost level only. | |
1828 | Aborting also gets out of only one level of recursive edit; it returns | |
1829 | immediately to the command level of the previous recursive edit. If you | |
1830 | wish, you can then abort the next recursive editing level. | |
1831 | ||
1832 | Alternatively, the command @kbd{M-x top-level} aborts all levels of | |
1833 | recursive edits, returning immediately to the top-level command reader. | |
1834 | ||
1835 | The text being edited inside the recursive edit need not be the same text | |
1836 | that you were editing at top level. It depends on what the recursive edit | |
1837 | is for. If the command that invokes the recursive edit selects a different | |
1838 | buffer first, that is the buffer you will edit recursively. In any case, | |
1839 | you can switch buffers within the recursive edit in the normal manner (as | |
1840 | long as the buffer-switching keys have not been rebound). You could | |
1841 | probably do all the rest of your editing inside the recursive edit, | |
1842 | visiting files and all. But this could have surprising effects (such as | |
1843 | stack overflow) from time to time. So remember to exit or abort the | |
1844 | recursive edit when you no longer need it. | |
1845 | ||
1846 | In general, we try to minimize the use of recursive editing levels in | |
1847 | GNU Emacs. This is because they constrain you to ``go back'' in a | |
1848 | particular order---from the innermost level toward the top level. When | |
1849 | possible, we present different activities in separate buffers so that | |
1850 | you can switch between them as you please. Some commands switch to a | |
1851 | new major mode which provides a command to switch back. These | |
1852 | approaches give you more flexibility to go back to unfinished tasks in | |
1853 | the order you choose. | |
1854 | ||
3f724e9a | 1855 | @node Emulation, Hyperlinking, Recursive Edit, Top |
6bf7aab6 DL |
1856 | @section Emulation |
1857 | @cindex emulating other editors | |
1858 | @cindex other editors | |
1859 | @cindex EDT | |
1860 | @cindex vi | |
3b65ce47 DL |
1861 | @cindex CRiSP |
1862 | @cindex Brief | |
1863 | @cindex PC keybindings | |
1864 | @cindex scrolling all windows | |
1865 | @cindex PC selecion | |
1866 | @cindex Motif keybindings | |
1867 | @cindex Macintosh keybindings | |
1868 | @cindex WordStar | |
6bf7aab6 DL |
1869 | |
1870 | GNU Emacs can be programmed to emulate (more or less) most other | |
1871 | editors. Standard facilities can emulate these: | |
1872 | ||
1873 | @table @asis | |
3b65ce47 DL |
1874 | @item CRiSP/Brief (PC editor) |
1875 | @findex crisp-mode | |
1876 | @vindex crisp-override-meta-x | |
1877 | @findex scroll-all-mode | |
1878 | Turn on keybindings to emulate the CRiSP/Brief editor with @kbd{M-x | |
1879 | crisp-mode}. Note that this rebinds @kbd{M-x} to exit Emacs unless you | |
1880 | change the user option @code{crisp-override-meta-x}. You can also load | |
1881 | the @code{scroll-all} package to emulate CRiSP's scroll-all feature | |
284983bd | 1882 | (scrolling all windows together). Do this either with @kbd{M-x |
3b65ce47 DL |
1883 | scroll-all-mode} or set the user option @code{crisp-load-scroll-all} to |
1884 | load it along with @code{crisp-mode}. | |
1885 | ||
6bf7aab6 DL |
1886 | @item EDT (DEC VMS editor) |
1887 | @findex edt-emulation-on | |
1888 | @findex edt-emulation-off | |
1889 | Turn on EDT emulation with @kbd{M-x edt-emulation-on}. @kbd{M-x | |
1890 | edt-emulation-off} restores normal Emacs command bindings. | |
1891 | ||
1892 | Most of the EDT emulation commands are keypad keys, and most standard | |
1893 | Emacs key bindings are still available. The EDT emulation rebindings | |
1894 | are done in the global keymap, so there is no problem switching | |
1895 | buffers or major modes while in EDT emulation. | |
1896 | ||
3b65ce47 DL |
1897 | @item `PC' bindings |
1898 | @findex pc-bindings-mode | |
1899 | @kbd{M-x pc-bindings-mode} sets up certain key bindings for `PC | |
1900 | compatibility'---what people are often used to on PCs---as follows: | |
1901 | @kbd{Delete} and its variants) delete forward instead of backward, | |
1902 | @kbd{C-Backspace} kills backward a word (as @kbd{C-Delete} normally | |
1903 | would), @kbd{M-Backspace} does undo, @kbd{Home} and @kbd{End} move to | |
1904 | beginning and end of line, @kbd{C-Home} and @kbd{C-End} move to | |
1905 | beginning and end of buffer and @kbd{C-Escape} does @code{list-buffers}. | |
1906 | ||
1907 | @item PC selection mode | |
1908 | @findex pc-selection-mode | |
1909 | @kbd{M-x pc-selction-mode} emulates the mark, copy, cut and paste | |
1910 | look-and-feel of Motif programs (which is the same as the Macintosh GUI | |
1911 | and MS-Windows). It makes the keybindings of PC mode and also modifies | |
1912 | the bindings of the cursor keys and the @kbd{next}, @kbd{prior}, | |
1913 | @kbd{home} and @kbd{end} keys. It does not provide the full set of CUA | |
1914 | keybindings---the fundamental Emacs keys @kbd{C-c}, @kbd{C-v} and | |
1915 | @kbd{C-x} are not rebound. | |
1916 | ||
1917 | The standard keys for moving around (@kbd{right}, @kbd{left}, @kbd{up}, | |
1918 | @kbd{down}, @kbd{home}, @kbd{end}, @kbd{prior}, @kbd{next}, called | |
1919 | ``move-keys'') will always de-activate the mark. Using @kbd{Shift} | |
1920 | together with the ``move keys'' activates the region over which they | |
1921 | move. The copy, cut and paste functions (as in many other programs) | |
1922 | operate on the active region, bound to @kbd{C-insert}, @kbd{S-delete} | |
1923 | and @kbd{S-insert} respectively. | |
1924 | ||
1925 | The @code{s-region} package provides similar, but less complete, | |
1926 | facilities. | |
1927 | ||
3f724e9a DL |
1928 | @item TPU (DEC VMS editor) |
1929 | @findex tpu-edt-on | |
1930 | @cindex TPU | |
1931 | @kbd{M-x tpu-edt-on} turns on emulation of the TPU editor emulating EDT. | |
1932 | ||
6bf7aab6 DL |
1933 | @item vi (Berkeley editor) |
1934 | @findex viper-mode | |
1935 | Viper is the newest emulator for vi. It implements several levels of | |
1936 | emulation; level 1 is closest to vi itself, while level 5 departs | |
1937 | somewhat from strict emulation to take advantage of the capabilities of | |
1938 | Emacs. To invoke Viper, type @kbd{M-x viper-mode}; it will guide you | |
1939 | the rest of the way and ask for the emulation level. @inforef{Top, | |
1940 | Viper, viper}. | |
1941 | ||
1942 | @item vi (another emulator) | |
1943 | @findex vi-mode | |
1944 | @kbd{M-x vi-mode} enters a major mode that replaces the previously | |
1945 | established major mode. All of the vi commands that, in real vi, enter | |
1946 | ``input'' mode are programmed instead to return to the previous major | |
1947 | mode. Thus, ordinary Emacs serves as vi's ``input'' mode. | |
1948 | ||
1949 | Because vi emulation works through major modes, it does not work | |
1950 | to switch buffers during emulation. Return to normal Emacs first. | |
1951 | ||
1952 | If you plan to use vi emulation much, you probably want to bind a key | |
1953 | to the @code{vi-mode} command. | |
1954 | ||
1955 | @item vi (alternate emulator) | |
1956 | @findex vip-mode | |
1957 | @kbd{M-x vip-mode} invokes another vi emulator, said to resemble real vi | |
1958 | more thoroughly than @kbd{M-x vi-mode}. ``Input'' mode in this emulator | |
1959 | is changed from ordinary Emacs so you can use @key{ESC} to go back to | |
1960 | emulated vi command mode. To get from emulated vi command mode back to | |
1961 | ordinary Emacs, type @kbd{C-z}. | |
1962 | ||
1963 | This emulation does not work through major modes, and it is possible | |
1964 | to switch buffers in various ways within the emulator. It is not | |
1965 | so necessary to assign a key to the command @code{vip-mode} as | |
1966 | it is with @code{vi-mode} because terminating insert mode does | |
1967 | not use it. | |
1968 | ||
1969 | @inforef{Top, VIP, vip}, for full information. | |
3b65ce47 DL |
1970 | |
1971 | @item WordStar (old wordprocessor) | |
1972 | @findex wordstar-mode | |
1973 | @kbd{M-x wordstar-mode} provides a major mode with WordStar-like | |
1974 | keybindings. | |
6bf7aab6 DL |
1975 | @end table |
1976 | ||
3f724e9a DL |
1977 | @node Hyperlinking, Dissociated Press, Emulation, Top |
1978 | @section Hyperlinking and Navigation Features | |
1979 | ||
1980 | @cindex hyperlinking | |
1981 | @cindex URLs | |
1982 | @cindex navigation | |
1983 | Various modes documented elsewhere have hypertext features whereby you | |
1984 | can follow links, usually with @kbd{mouse-2} or @kbd{RET} on the text of | |
1985 | the link. Info mode, Help mode and the Dired-like modes are examples. | |
1986 | The Tags facility (@pxref{Tags}) links between source files. | |
1987 | ||
1988 | Other non-mode-specific facilities are available to follow links from | |
1989 | the current buffer in a context-sensitive fashion. | |
1990 | ||
1991 | @table @asis | |
1992 | @item Browse-URL (follow URLs) | |
1993 | @cindex World Wide Web | |
1994 | @findex browse-url | |
1995 | @findex browse-url-at-point | |
1996 | @findex browse-url-at-mouse | |
1997 | @vindex browse-url-browser-function | |
1998 | @cindex Browse-URL | |
1999 | @cindex URLs | |
2000 | The Browse-URL package provides facilities for following URLs specifying | |
2001 | links on the World Wide Web. Usually this works by invoking a web | |
2002 | browser, but you can, for instance, invoke @code{compose-mail} from | |
2003 | @samp{mailto:} URLs. Packages such as Gnus may make active links from | |
2004 | URLs themselves. Otherwise you can use @kbd{M-x browse-url} to follow a | |
2005 | link, defaulting to the URL at point. Other commands are available | |
2006 | which you might like to bind to keys, such as @code{browse-url-at-point} | |
2007 | and @code{browse-url-at-mouse}. | |
2008 | ||
2009 | You can customize Browse-URL's behaviour via various options in the | |
2010 | @samp{browse-url} Customize group, particularly | |
2011 | @code{browse-url-browser-function}. You can invoke actions dependent on | |
2012 | the type of URL by defining @code{browse-url-browser-function} as an | |
2013 | association list. The package's commentary available via @kbd{C-h p} | |
2014 | provides more information. Packages with facilities for following URLs | |
2015 | generally should use Browse-URL, so customizing the Browse-URL group | |
2016 | should be sufficient to determine how they all work. | |
2017 | ||
2018 | @item Goto-address (activate URLs) | |
2019 | @findex goto-address | |
2020 | @cindex Goto-address | |
2021 | @cindex URLs, activating | |
2022 | You can arrange to activate URLs in any buffer with @kbd{M-x | |
2023 | goto-address}. It may be useful to add @code{goto-address} to hooks | |
2024 | invoked when buffers are displayed in particular modes. | |
2025 | @code{rmail-show-message-hook} is the appropriate hook if you use Rmail, | |
2026 | or @code{mh-show-mode-hook} if you use MH. | |
2027 | ||
2028 | @item FFAP (find at point) | |
2029 | @findex ffap | |
2030 | @findex find-file-at-point | |
2031 | @findex ffap | |
2032 | @findex ffap-bindings | |
2033 | @cindex FFAP | |
2034 | The package @samp{ffap} provides functions for finding files and URLs at | |
2035 | point. Specifically, @code{find-file-at-point} (abbreviated as | |
2036 | @code{ffap}) can be used as as replacement for @kbd{M-x find-file}. A | |
2037 | set of default bindings can be set up by the function | |
2038 | @code{ffap-bindings}. The package's commentary available via @kbd{C-h | |
2039 | p} provides more information. | |
2040 | ||
2041 | @item Find-func (find function and variable definitions) | |
2042 | @findex find-function | |
2043 | @findex find-function-on-key | |
2044 | @findex find-variable | |
2045 | @findex auto-compression-mode | |
2046 | @cindex examples of Lisp functions | |
2047 | @cindex Lisp examples | |
2048 | @cindex Find-func | |
2049 | @cindex Lisp definitions | |
2050 | @cindex definitions, locating in sources | |
2051 | @cindex tags | |
2052 | The Find-func package provides convenient facilities for finding the | |
2053 | definitions of Emacs Lisp functions and variables. It has a somewhat | |
2054 | similar function to the Tags facility (@pxref{Tags}) but uses Emacs's | |
2055 | introspective facilities which maintain information about loaded | |
2056 | libraries. In contrast to Tags, it only works for functions and | |
2057 | variables with definitions which are already loaded but it relates to | |
2058 | the code actually running and doesn't require maintaining tags files. | |
2059 | ||
2060 | You need to have the Lisp source (@samp{.el}) files available on your | |
2061 | load path along with the compiled (@samp{.elc}) versions for this to | |
2062 | work. The sources may be compressed if you turn on | |
2063 | @samp{auto-compression-mode}. | |
2064 | ||
2065 | The commands available include @kbd{M-x find-function} to find the | |
2066 | definition of a named function, @kbd{find-function-on-key} to find the | |
2067 | definition of the function bound to a key and @kbd{find-variable} to | |
2068 | find a variable's definition. These only work for things defined in | |
2069 | Lisp source files, not primitive functions or variables defined | |
2070 | primitively in the Emacs layer implemented in C. | |
2071 | ||
2072 | Find-func is useful for finding examples of how to do things if you want | |
2073 | to write an Emacs Lisp extension similar to some existing function. | |
2074 | ||
2075 | @item Imenu (indexing in a buffer) | |
2076 | The Imenu package provides navigation amongst items indexed in the current | |
2077 | buffer. @xref{Imenu}. | |
2078 | ||
2079 | @item Info-lookup (finding documentation of items) | |
2080 | @cindex Info | |
2081 | @cindex documentation lookup | |
2082 | The Info-lookup package provides a major mode-sensitive facility for | |
2083 | looking up definitions in Info indexes. @xref{Documentation}. | |
2084 | ||
2085 | @item Speedbar (navigation bar) | |
2086 | @findex speedbar | |
2087 | @cindex browser | |
2088 | Speedbar maintains a frame in which files, and locations in files are | |
2089 | displayed. @xref{Speedbar}. | |
2090 | ||
2091 | @end table | |
2092 | ||
2093 | @node Dissociated Press, Amusements, Hyperlinking, Top | |
6bf7aab6 DL |
2094 | @section Dissociated Press |
2095 | ||
2096 | @findex dissociated-press | |
2097 | @kbd{M-x dissociated-press} is a command for scrambling a file of text | |
2098 | either word by word or character by character. Starting from a buffer of | |
2099 | straight English, it produces extremely amusing output. The input comes | |
2100 | from the current Emacs buffer. Dissociated Press writes its output in a | |
2101 | buffer named @samp{*Dissociation*}, and redisplays that buffer after every | |
2102 | couple of lines (approximately) so you can read the output as it comes out. | |
2103 | ||
2104 | Dissociated Press asks every so often whether to continue generating | |
2105 | output. Answer @kbd{n} to stop it. You can also stop at any time by | |
2106 | typing @kbd{C-g}. The dissociation output remains in the | |
2107 | @samp{*Dissociation*} buffer for you to copy elsewhere if you wish. | |
2108 | ||
2109 | @cindex presidentagon | |
2110 | Dissociated Press operates by jumping at random from one point in the | |
2111 | buffer to another. In order to produce plausible output rather than | |
2112 | gibberish, it insists on a certain amount of overlap between the end of | |
2113 | one run of consecutive words or characters and the start of the next. | |
2114 | That is, if it has just printed out `president' and then decides to jump | |
2115 | to a different point in the file, it might spot the `ent' in `pentagon' | |
2116 | and continue from there, producing `presidentagon'.@footnote{This | |
2117 | dissociword actually appeared during the Vietnam War, when it was very | |
2118 | appropriate.} Long sample texts produce the best results. | |
2119 | ||
2120 | @cindex againformation | |
2121 | A positive argument to @kbd{M-x dissociated-press} tells it to operate | |
2122 | character by character, and specifies the number of overlap characters. A | |
2123 | negative argument tells it to operate word by word and specifies the number | |
2124 | of overlap words. In this mode, whole words are treated as the elements to | |
2125 | be permuted, rather than characters. No argument is equivalent to an | |
2126 | argument of two. For your againformation, the output goes only into the | |
2127 | buffer @samp{*Dissociation*}. The buffer you start with is not changed. | |
2128 | ||
2129 | @cindex Markov chain | |
2130 | @cindex ignoriginal | |
2131 | @cindex techniquitous | |
2132 | Dissociated Press produces nearly the same results as a Markov chain | |
2133 | based on a frequency table constructed from the sample text. It is, | |
2134 | however, an independent, ignoriginal invention. Dissociated Press | |
2135 | techniquitously copies several consecutive characters from the sample | |
2136 | between random choices, whereas a Markov chain would choose randomly for | |
2137 | each word or character. This makes for more plausible sounding results, | |
2138 | and runs faster. | |
2139 | ||
2140 | @cindex outragedy | |
2141 | @cindex buggestion | |
2142 | @cindex properbose | |
2143 | @cindex mustatement | |
2144 | @cindex developediment | |
2145 | @cindex userenced | |
2146 | It is a mustatement that too much use of Dissociated Press can be a | |
2147 | developediment to your real work. Sometimes to the point of outragedy. | |
2148 | And keep dissociwords out of your documentation, if you want it to be well | |
2149 | userenced and properbose. Have fun. Your buggestions are welcome. | |
2150 | ||
2151 | @node Amusements, Customization, Dissociated Press, Top | |
2152 | @section Other Amusements | |
2153 | @cindex boredom | |
2154 | @findex hanoi | |
2155 | @findex yow | |
2156 | @findex gomoku | |
6bf7aab6 DL |
2157 | @cindex tower of Hanoi |
2158 | ||
2159 | If you are a little bit bored, you can try @kbd{M-x hanoi}. If you are | |
2160 | considerably bored, give it a numeric argument. If you are very very | |
2161 | bored, try an argument of 9. Sit back and watch. | |
2162 | ||
2163 | @cindex Go Moku | |
2164 | If you want a little more personal involvement, try @kbd{M-x gomoku}, | |
2165 | which plays the game Go Moku with you. | |
2166 | ||
2167 | @findex blackbox | |
2168 | @findex mpuz | |
3b65ce47 | 2169 | @findex 5x5 |
6bf7aab6 | 2170 | @cindex puzzles |
3b65ce47 | 2171 | @kbd{M-x blackbox}, @kbd{M-x mpuz} and @kbd{M-x 5x5} are kinds of puzzles. |
6bf7aab6 DL |
2172 | @code{blackbox} challenges you to determine the location of objects |
2173 | inside a box by tomography. @code{mpuz} displays a multiplication | |
2174 | puzzle with letters standing for digits in a code that you must | |
2175 | guess---to guess a value, type a letter and then the digit you think it | |
3b65ce47 | 2176 | stands for. The aim of @code{5x5} is to fill in all the squares. |
6bf7aab6 DL |
2177 | |
2178 | @findex dunnet | |
2179 | @kbd{M-x dunnet} runs an adventure-style exploration game, which is | |
2180 | a bigger sort of puzzle. | |
2181 | ||
3b65ce47 DL |
2182 | @findex lm |
2183 | @cindex landmark game | |
2184 | @kbd{M-x lm} runs a relatively non-participatory game in which a robot | |
2185 | attempts to maneuver towards a tree at the center of the window based on | |
2186 | unique olfactory cues from each of the four directions. | |
2187 | ||
2188 | @findex life | |
2189 | @cindex Life | |
2190 | @kbd{M-x life} runs Conway's `Life' cellular automaton. | |
2191 | ||
2192 | @findex solitaire | |
2193 | @cindex solitaire | |
2194 | @kbd{M-x solitaire} plays a game of solitaire in which you jump pegs | |
2195 | across other pegs. | |
2196 | ||
2197 | @findex tetris | |
2198 | @cindex Tetris | |
2199 | @kbd{M-x tetris} runs an implementation of the well-known Tetris game. | |
2200 | @findex snake | |
2201 | @cindex Snake | |
2202 | Likewise, @kbd{M-x snake} provides an implementation of Snake. | |
2203 | ||
6bf7aab6 DL |
2204 | When you are frustrated, try the famous Eliza program. Just do |
2205 | @kbd{M-x doctor}. End each input by typing @key{RET} twice. | |
2206 | ||
2207 | @cindex Zippy | |
2208 | When you are feeling strange, type @kbd{M-x yow}. |