![[BACK]](/cvsweb/icons/back.gif){kind=icon}
Return to emacs-5 CVS log ![[TXT]](/cvsweb/icons/text.gif){kind=icon}
![[DIR]](/cvsweb/icons/dir.gif){kind=icon}
Up to [CSRG BSD Unix] / 43BSDReno / contrib / emacs-18.55 / info|
Return to emacs-5 CVS log | Up to [CSRG BSD Unix] / 43BSDReno / contrib / emacs-18.55 / info |
1.1 root 1: Info file emacs, produced by texinfo-format-buffer -*-Text-*-
2: from file emacs.tex
3:
4: This file documents the GNU Emacs editor.
5:
6: Copyright (C) 1985, 1986 Richard M. Stallman.
7:
8: Permission is granted to make and distribute verbatim copies of
9: this manual provided the copyright notice and this permission notice
10: are preserved on all copies.
11:
12: Permission is granted to copy and distribute modified versions of this
13: manual under the conditions for verbatim copying, provided also that the
14: sections entitled "The GNU Manifesto", "Distribution" and "GNU Emacs
15: General Public License" are included exactly as in the original, and
16: provided that the entire resulting derived work is distributed under the
17: terms of a permission notice identical to this one.
18:
19: Permission is granted to copy and distribute translations of this manual
20: into another language, under the above conditions for modified versions,
21: except that the sections entitled "The GNU Manifesto", "Distribution"
22: and "GNU Emacs General Public License" may be included in a translation
23: approved by the author instead of in the original English.
24:
25:
26: File: emacs Node: Reverting, Prev: Saving, Up: Files, Next: Auto Save
27:
28: Reverting a Buffer
29: ==================
30:
31: If you have made extensive changes to a file and then change your mind
32: about them, you can get rid of them by reading in the previous version of
33: the file. To do this, use `M-x revert-buffer', which operates on the
34: current buffer. Since this is a very dangerous thing to do, you must
35: confirm it with `yes'.
36:
37: If the current buffer has been auto-saved more recently than it has been
38: saved for real, `revert-buffer' offers to read the auto save file
39: instead of the visited file (*Note Auto Save::). This question comes
40: before the usual request for confirmation, and demands `y' or `n'
41: as an answer. If you have started to type `yes' for confirmation
42: without realizing that the other question was going to be asked, the
43: `y' will answer that question, but the `es' will not be valid
44: confirmation. So you will have a chance to cancel the operation with
45: `C-g' and try it again with the answers that you really intend.
46:
47: `revert-buffer' keeps point at the same distance (measured in
48: characters) from the beginning of the file. If the file was edited only
49: slightly, you will be at approximately the same piece of text after
50: reverting as before. If you have made drastic changes, the same value of
51: point in the old file may address a totally different piece of text.
52:
53: A buffer reverted from its visited file is marked "not modified" until
54: another change is made.
55:
56: Some kinds of buffers whose contents reflect data bases other than files,
57: such as Dired buffers, can also be reverted. For them, reverting means
58: recalculating their contents from the appropriate data base. Buffers
59: created randomly with `C-x b' cannot be reverted; `revert-buffer'
60: reports an error when asked to do so.
61:
62:
63: File: emacs Node: Auto Save, Prev: Reverting, Up: Files, Next: ListDir
64:
65: Auto-Saving: Protection Against Disasters
66: =========================================
67:
68: Emacs saves all the visited files from time to time (based on counting
69: your keystrokes) without being asked. This is called "auto-saving".
70: It prevents you from losing more than a limited amount of work if the
71: system crashes.
72:
73: When Emacs determines that it is time for auto-saving, each buffer is
74: considered, and is auto-saved if auto-saving is turned on for it and it has
75: been changed since the last time it was auto-saved. If any auto-saving is
76: done, the message `Auto-saving...' is displayed in the echo area until
77: auto-saving is finished. Errors occurring during auto-saving are caught
78: so that they do not interfere with the execution of commands you have been
79: typing.
80:
81: * Menu:
82:
83: * Files: Auto Save Files.
84: * Control: Auto Save Control.
85: * Recover:: Recovering text from auto-save files.
86:
87:
88: File: emacs Node: Auto Save Files, Prev: Auto Save, Up: Auto Save, Next: Auto Save Control
89:
90: Auto-Save Files
91: ---------------
92:
93: Auto-saving does not normally save in the files that you visited, because
94: it can be very undesirable to save a program that is in an inconsistent
95: state when you have made half of a planned change. Instead, auto-saving
96: is done in a different file called the "auto-save file", and the
97: visited file is changed only when you request saving explicitly (such as
98: with `C-x C-s').
99:
100: Normally, the auto-save file name is made by appending `#' to the
101: front and rear of the visited file name. Thus, a buffer visiting file
102: `foo.c' would be auto-saved in a file `#foo.c#'. Most buffers
103: that are not visiting files are auto-saved only if you request it
104: explicitly; when they are auto-saved, the auto-save file name is made by
105: appending `#%' to the front and `#' to the rear of buffer name.
106: For example, the `*mail*' buffer in which you compose messages to be
107: sent is auto-saved in a file named `#%*mail*#'. Auto-save file names
108: are made this way unless you reprogram parts of Emacs to do something
109: different (the functions `make-auto-save-file-name' and
110: `auto-save-file-name-p'). The file name to be used for auto-saving
111: in a buffer is calculated when auto-saving is turned on in that buffer.
112:
113: If you want auto-saving to be done in the visited file, set the variable
114: `auto-save-visited-file-name' to be non-`nil'. In this mode,
115: there is really no difference between auto-saving and explicit saving.
116:
117: A buffer's auto-save file is deleted when you save the buffer in its
118: visited file. To inhibit this, set the variable `delete-auto-save-files'
119: to `nil'. Changing the visited file name with `C-x C-w' or
120: `set-visited-file-name' renames any auto-save file to go with
121: the new visited name.
122:
123:
124: File: emacs Node: Auto Save Control, Prev: Auto Save Files, Up: Auto Save, Next: Recover
125:
126: Controlling Auto-Saving
127: -----------------------
128:
129: Each time you visit a file, auto-saving is turned on for that file's
130: buffer if the variable `auto-save-default' is non-`nil' (but not
131: in batch mode; *Note Entering Emacs::). The default for this variable is
132: `t', so auto-saving is the usual practice for file-visiting buffers.
133: Auto-saving can be turned on or off for any existing buffer with the
134: command `M-x auto-save-mode'. Like other minor mode commands, `M-x
135: auto-save-mode' turns auto-saving on with a positive argument, off with a
136: zero or negative argument; with no argument, it toggles.
137:
138: Emacs does auto-saving periodically based on counting how many characters
139: you have typed since the last time auto-saving was done. The variable
140: `auto-save-interval' specifies how many characters there are between
141: auto-saves. By default, it is 300. Emacs also auto-saves whenever you
142: call the function `do-auto-save'.
143:
144: Emacs also does auto-saving whenever it gets a fatal error. This
145: includes killing the Emacs job with a shell command such as `kill
146: %emacs', or disconnecting a phone line or network connection.
147:
148:
149: File: emacs Node: Recover, Prev: Auto Save Control, Up: Auto Save
150:
151: Recovering Data from Auto-Saves
152: -------------------------------
153:
154: The way to use the contents of an auto-save file to recover from a loss
155: of data is with the command `M-x recover-file RET FILE RET'. This visits
156: FILE and then (after your confirmation) restores the contents from from its
157: auto-save file `#FILE#'. You can then save with `C-x C-s' to put the
158: recovered text into FILE itself. For example, to recover file `foo.c' from
159: its auto-save file `#foo.c#', do:
160:
161: M-x recover-file RET foo.c RET
162: C-x C-s
163:
164: Before asking for confirmation, `M-x recover-file' displays a
165: directory listing describing the specified file and the auto-save file,
166: so you can compare their sizes and dates. If the auto-save file
167: is older, `M-x recover-file' does not offer to read it.
168:
169: Auto-saving is disabled by `M-x recover-file' because using
170: this command implies that the auto-save file contains valuable data
171: from a past session. If you save the data in the visited file and
172: then go on to make new changes, you should turn auto-saving back on
173: with `M-x auto-save-mode'.
174:
175:
176: File: emacs Node: ListDir, Prev: Auto Save, Up: Files, Next: Dired
177:
178: Listing a File Directory
179: ========================
180:
181: Files are classified by Unix into "directories". A "directory
182: listing" is a list of all the files in a directory. Emacs provides
183: directory listings in brief format (file names only) and verbose format
184: (sizes, dates, and authors included).
185:
186: `C-x C-d DIR-OR-PATTERN'
187: Print a brief directory listing (`list-directory').
188: `C-u C-x C-d DIR-OR-PATTERN'
189: Print a verbose directory listing.
190:
191: The command to print a directory listing is `C-x C-d' (`list-directory').
192: It reads using the minibuffer a file name which is either a directory to be
193: listed or a wildcard-containing pattern for the files to be listed. For
194: example,
195:
196: C-x C-d /u2/emacs/etc RET
197:
198: lists all the files in directory `/u2/emacs/etc'. An example of
199: specifying a file name pattern is
200:
201: C-x C-d /u2/emacs/src/*.c RET
202:
203: Normally, `C-x C-d' prints a brief directory listing containing just
204: file names. A numeric argument (regardless of value) tells it to print a
205: verbose listing (like `ls -l').
206:
207: The text of a directory listing is obtained by running `ls' in an
208: inferior process. Two Emacs variables control the switches passed to
209: `ls': `list-directory-brief-switches' is a string giving the
210: switches to use in brief listings (`"-CF"' by default), and
211: `list-directory-verbose-switches' is a string giving the switches to
212: use in a verbose listing (`"-l"' by default).
213:
214:
215: File: emacs Node: Dired, Prev: ListDir, Up: Files, Next: Misc File Ops
216:
217: Dired, the Directory Editor
218: ===========================
219:
220: Dired makes it easy to delete or visit many of the files in a single
221: directory at once. It makes an Emacs buffer containing a listing of the
222: directory. You can use the normal Emacs commands to move around in this
223: buffer, and special Dired commands to operate on the files.
224:
225: * Menu:
226:
227: * Enter: Dired Enter. How to invoke Dired.
228: * Edit: Dired Edit. Editing the Dired buffer.
229: * Deletion: Dired Deletion. Deleting files with Dired.
230: * Immed: Dired Immed. Other file operations through Dired.
231:
232:
233: File: emacs Node: Dired Enter, Prev: Dired, Up: Dired, Next: Dired Edit
234:
235: Entering Dired
236: --------------
237:
238: To invoke dired, do `C-x d' or `M-x dired'. The command reads a
239: directory name or wildcard file name pattern as a minibuffer argument just
240: like the `list-directory' command, `C-x C-d'. Where `dired'
241: differs from `list-directory' is in naming the buffer after the
242: directory name or the wildcard pattern used for the listing, and putting
243: the buffer into Dired mode so that the special commands of Dired are
244: available in it. The variable `dired-listing-switches' is a string
245: used as an argument to `ls' in making the directory; this string
246: must contain `-l'.
247:
248: To display the Dired buffer in another window rather than in the selected
249: window, use `C-x 4 d' (`dired-other-window)' instead of `C-x d'.
250:
251:
252: File: emacs Node: Dired Edit, Prev: Dired Enter, Up: Dired, Next: Dired Deletion
253:
254: Editing in Dired
255: ----------------
256:
257: Once the Dired buffer exists, you can switch freely between it and other
258: Emacs buffers. Whenever the Dired buffer is selected, certain special
259: commands are provided that operate on files that are listed. The Dired
260: buffer is "read-only", and inserting text in it is not useful, so
261: ordinary printing characters such as `d' and `x' are used for Dired
262: commands. Most Dired commands operate on the file described by the line
263: that point is on. Some commands perform operations immediately; others
264: "flag" the file to be operated on later.
265:
266: Most Dired commands that operate on the current line's file also treat a
267: numeric argument as a repeat count, meaning to act on the files of the
268: next few lines. A negative argument means to operate on the files of the
269: preceding lines, and leave point on the first of those lines.
270:
271: All the usual Emacs cursor motion commands are available in Dired
272: buffers. Some special purpose commands are also provided. The keys
273: `C-n' and `C-p' are redefined so that they try to position
274: the cursor at the beginning of the filename on the line, rather than
275: at the beginning of the line.
276:
277: For extra convenience, SPC and `n' in Dired are equivalent to `C-n'. `p'
278: is equivalent to `C-p'. Moving by lines is done so often in Dired that it
279: deserves to be easy to type. DEL (move up and unflag) is often useful
280: simply for moving up.
281:
282: The `g' command in Dired runs `revert-buffer' to reinitialize
283: the buffer from the actual disk directory and show any changes made in the
284: directory by programs other than Dired. All deletion flags in the Dired
285: buffer are lost when this is done.
286:
287:
288: File: emacs Node: Dired Deletion, Prev: Dired Edit, Up: Dired, Next: Dired Immed
289:
290: Deleting Files with Dired
291: -------------------------
292:
293: The primary use of Dired is to flag files for deletion and then delete
294: them.
295:
296: `d'
297: Flag this file for deletion.
298: `u'
299: Remove deletion-flag on this line.
300: `DEL'
301: Remove deletion-flag on previous line, moving point to that line.
302: `x'
303: Delete the files that are flagged for deletion.
304: `#'
305: Flag all auto-save files (files whose names start and end with `#')
306: for deletion (*Note Auto Save::).
307: `~'
308: Flag all backup files (files whose names end with `~') for deletion
309: (*Note Backup::).
310: `. (Period)'
311: Flag excess numeric backup files for deletion. The oldest and newest
312: few backup files of any one file are exempt; the middle ones are flagged.
313:
314: You can flag a file for deletion by moving to the line describing the
315: file and typing `d' or `C-d'. The deletion flag is visible as a
316: `D' at the beginning of the line. Point is moved to the beginning of
317: the next line, so that repeated `d' commands flag successive files.
318:
319: The files are flagged for deletion rather than deleted immediately to
320: avoid the danger of deleting a file accidentally. Until you direct Dired
321: to delete the flagged files, you can remove deletion flags using the
322: commands `u' and DEL. `u' works just like `d', but
323: removes flags rather than making flags. DEL moves upward, removing
324: flags; it is like `u' with numeric argument automatically negated.
325:
326: To delete the flagged files, type `x'. This command first displays a
327: list of all the file names flagged for deletion, and requests confirmation
328: with `yes'. Once you confirm, all the flagged files are deleted, and their
329: lines are deleted from the text of the Dired buffer. The shortened Dired
330: buffer remains selected. If you answer `no' or quit with `C-g', you
331: return immediately to Dired, with the deletion flags still present and no
332: files actually deleted.
333:
334: The `#', `~' and `.' commands flag many files for deletion, based on
335: their names. These commands are useful precisely because they do not
336: actually delete any files; you can remove the deletion flags from any
337: flagged files that you really wish to keep.
338:
339: `#' flags for deletion all files that appear to have been made by
340: auto-saving (that is, files whose names begin and end with `#').
341: `~' flags for deletion all files that appear to have been made as
342: backups for files that were edited (that is, files whose names end with
343: `~').
344:
345: `.' (Period) flags just some of the backup files for deletion: only
346: numeric backups that are not among the oldest few nor the newest few
347: backups of any one file. Normally `dired-kept-versions' (not
348: `kept-new-versions'; that applies only when saving) specifies the number of
349: newest versions of each file to keep, and `kept-old-versions' specifies the
350: number of oldest versions to keep. Period with a positive numeric
351: argument, as in `C-u 3 .', specifies the number of newest versions to keep,
352: overriding `dired-kept-versions'. A negative numeric argument overrides
353: `kept-old-versions', using minus the value of the argument to specify the
354: number of oldest versions of each file to keep.
355:
356:
357: File: emacs Node: Dired Immed, Prev: Dired Deletion, Up: Dired
358:
359: Immediate File Operations in Dired
360: ----------------------------------
361:
362: Some file operations in Dired take place immediately when they are
363: requested.
364:
365: `c'
366: Copies the file described on the current line. You must supply a file name
367: to copy to, using the minibuffer.
368: `f'
369: Visits the file described on the current line. It is just like typing
370: `C-x C-f' and supplying that file name. If the file on this line is a
371: subdirectory, `f' actually causes Dired to be invoked on that
372: subdirectory. *Note Visiting::.
373: `o'
374: Like `f', but uses another window to display the file's buffer. The
375: Dired buffer remains visible in the first window. This is like using
376: `C-x 4 C-f' to visit the file. *Note Windows::.
377: `r'
378: Renames the file described on the current line. You must supply a file
379: name to rename to, using the minibuffer.
380: `v'
381: Views the file described on this line using `M-x view-file'. Viewing
382: a file is like visiting it, but is slanted toward moving around in the
383: file conveniently and does not allow changing the file. *Note View
384: File: Misc File Ops. Viewing a file that is a directory runs Dired on
385: that directory.
386:
387:
388: File: emacs Node: Misc File Ops, Prev: Dired, Up: Files
389:
390: Miscellaneous File Operations
391: =============================
392:
393: Emacs has commands for performing many other operations on files.
394: All operate on one file; they do not accept wild card file names.
395:
396: `M-x view-file' allows you to scan or read a file by sequential
397: screenfuls. It reads a file name argument using the minibuffer. After
398: reading the file into an Emacs buffer, `view-file' reads and displays
399: one windowful. You can then type SPC to scroll forward one windowful,
400: or DEL to scroll backward. Various other commands are provided for
401: moving around in the file, but none for changing it; type `C-h' while
402: viewing for a list of them. They are mostly the same as normal Emacs
403: cursor motion commands. To exit from viewing, type `C-c'.
404:
405: `M-x insert-file' inserts a copy of the contents of the specified
406: file into the current buffer at point, leaving point unchanged before the
407: contents and the mark after them. *Note Mark::.
408:
409: `M-x write-region' is the inverse of `M-x insert-file'; it copies
410: the contents of the region into the specified file. `M-x append-to-file'
411: adds the text of the region to the end of the specified file.
412:
413: `M-x delete-file' deletes the specified file, like the `rm'
414: command in the shell. If you are deleting many files in one directory, it
415: may be more convenient to use Dired (*Note Dired::).
416:
417: `M-x rename-file' reads two file names OLD and NEW using
418: the minibuffer, then renames file OLD as NEW. If a file named
419: NEW already exists, you must confirm with `yes' or renaming is not
420: done; this is because renaming causes the old meaning of the name NEW
421: to be lost. If OLD and NEW are on different file systems, the
422: file OLD is copied and deleted.
423:
424: The similar command `M-x add-name-to-file' is used to add an
425: additional name to an existing file without removing its old name.
426: The new name must belong on the same file system that the file is on.
427:
428: `M-x copy-file' reads the file OLD and writes a new file named
429: NEW with the same contents. Confirmation is required if a file named
430: NEW already exists, because copying has the consequence of overwriting
431: the old contents of the file NEW.
432:
433: `M-x make-symbolic-link' reads two file names OLD and LINKNAME,
434: and then creates a symbolic link named LINKNAME and pointing at OLD.
435: The effect is that future attempts to open file LINKNAME will refer
436: to whatever file is named OLD at the time the opening is done, or
437: will get an error if the name OLD is not in use at that time.
438: Confirmation is required when creating the link if LINKNAME is in
439: use. Note that not all systems support symbolic links.
440:
441:
442: File: emacs Node: Buffers, Prev: Files, Up: Top, Next: Windows
443:
444: Using Multiple Buffers
445: **********************
446:
447: The text you are editing in Emacs resides in an object called a
448: "buffer". Each time you visit a file, a buffer is created to hold the
449: file's text. Each time you invoke Dired, a buffer is created to hold the
450: directory listing. If you send a message with `C-x m', a buffer named
451: `*mail*' is used to hold the text of the message. When you ask for a
452: command's documentation, that appears in a buffer called `*Help*'.
453:
454: At any time, one and only one buffer is "selected". It is also
455: called the "current buffer". Often we say that a command operates on
456: "the buffer" as if there were only one; but really this means that the
457: command operates on the selected buffer (most commands do).
458:
459: When Emacs makes multiple windows, each window has a chosen buffer which
460: is displayed there, but at any time only one of the windows is selected and
461: its chosen buffer is the selected buffer. Each window's mode line displays
462: the name of the buffer that the window is displaying (*Note Windows::).
463:
464: Each buffer has a name, which can be of any length, and you can select
465: any buffer by giving its name. Most buffers are made by visiting files,
466: and their names are derived from the files' names. But you can also create
467: an empty buffer with any name you want. A newly started Emacs has a buffer
468: named `*scratch*' which can be used for evaluating Lisp expressions in
469: Emacs. The distinction between upper and lower case matters in buffer
470: names.
471:
472: Each buffer records individually what file it is visiting, whether it is
473: modified, and what major mode and minor modes are in effect in it
474: (*Note Major Modes::). Any Emacs variable can be made "local to" a
475: particular buffer, meaning its value in that buffer can be different from
476: the value in other buffers. *Note Locals::.
477:
478: * Menu:
479:
480: * Select Buffer:: Creating a new buffer or reselecting an old one.
481: * List Buffers:: Getting a list of buffers that exist.
482: * Misc Buffer:: Renaming; changing read-onliness; copying text.
483: * Kill Buffer:: Killing buffers you no longer need.
484: * Several Buffers:: How to go through the list of all buffers
485: and operate variously on several of them.
486:
487:
488: File: emacs Node: Select Buffer, Prev: Buffers, Up: Buffers, Next: List Buffers
489:
490: Creating and Selecting Buffers
491: ==============================
492:
493: `C-x b BUFFER RET'
494: Select or create a buffer named BUFFER (`switch-to-buffer').
495: `C-x 4 b BUFFER RET'
496: Similar but select a buffer named BUFFER in another window
497: (`switch-to-buffer-other-window').
498:
499: To select the buffer named BUFNAME, type `C-x b BUFNAME RET'. This is
500: the command `switch-to-buffer' with argument BUFNAME. You can use
501: completion on an abbreviation for the buffer name you want (*Note
502: Completion::). An empty argument to `C-x b' specifies the most recently
503: selected buffer that is not displayed in any window.
504:
505: Most buffers are created by visiting files, or by Emacs commands that
506: want to display some text, but you can also create a buffer explicitly by
507: typing `C-x b BUFNAME RET'. This makes a new, empty buffer which
508: is not visiting any file, and selects it for editing. Such buffers are
509: used for making notes to yourself. If you try to save one, you are asked
510: for the file name to use. The new buffer's major mode is determined by the
511: value of `default-major-mode' (*Note Major Modes::).
512:
513: Note that `C-x C-f', and any other command for visiting a file, can
514: also be used to switch buffers. *Note Visiting::.
515:
516:
517: File: emacs Node: List Buffers, Prev: Select Buffer, Up: Buffers, Next: Misc Buffer
518:
519: Listing Existing Buffers
520: ========================
521:
522: `C-x C-b'
523: List the existing buffers (`list-buffers').
524:
525: To print a list of all the buffers that exist, type `C-x C-b'. Each line
526: in the list shows one buffer's name, major mode and visited file. `*' at
527: the beginning of a line indicates the buffer is "modified". If several
528: buffers are modified, it may be time to save some with `C-x s' (*Note
529: Saving::). `%' indicates a read-only buffer. `.' marks the selected
530: buffer. Here is an example of a buffer list:
531:
532: MR Buffer Size Mode File
533: -- ------ ---- ---- ----
534: .* emacs.tex 383402 Texinfo /u2/emacs/man/emacs.tex
535: *Help* 1287 Fundamental
536: files.el 23076 Emacs-Lisp /u2/emacs/lisp/files.el
537: % RMAIL 64042 RMAIL /u/rms/RMAIL
538: *% man 747 Dired
539: net.emacs 343885 Fundamental /u/rms/net.emacs
540: fileio.c 27691 C /u2/emacs/src/fileio.c
541: NEWS 67340 Text /u2/emacs/etc/NEWS
542: *scratch* 0 Lisp Interaction
543:
544: Note that the buffer `*Help*' was made by a help request; it is not
545: visiting any file. The buffer `man' was made by Dired on the
546: directory `/u2/emacs/man/'.
547:
548:
549: File: emacs Node: Misc Buffer, Prev: List Buffers, Up: Buffers, Next: Kill Buffer
550:
551: Miscellaneous Buffer Operations
552: ===============================
553:
554: `C-x C-q'
555: Toggle read-only status of buffer (`toggle-read-only').
556: `M-x rename-buffer'
557: Change the name of the current buffer.
558: `M-x view-buffer'
559: Scroll through a buffer.
560:
561: A buffer can be "read-only", which means that commands to change its
562: text are not allowed. Normally, read-only buffers are made by subsystems
563: such as Dired and Rmail that have special commands to operate on the text;
564: a read-only buffer is also made if you visit a file that is protected so
565: you cannot write it. If you wish to make changes in a read-only buffer,
566: use the command `C-x C-q' (`toggle-read-only'). It makes a
567: read-only buffer writable, and makes a writable buffer read-only. This
568: works by setting the variable `buffer-read-only', which has a local
569: value in each buffer and makes the buffer read-only if its value is
570: non-`nil'.
571:
572: `M-x rename-buffer' changes the name of the current buffer. Specify
573: the new name as a minibuffer argument. There is no default. If you
574: specify a name that is in use for some other buffer, an error happens and
575: no renaming is done.
576:
577: `M-x view-buffer' is much like `M-x view-file' (*Note Misc File Ops::)
578: except that it examines an already existing Emacs buffer. View mode
579: provides commands for scrolling through the buffer conveniently but not
580: for changing it. When you exit View mode, the value of point that resulted
581: from your perusal remains in effect.
582:
583: The commands `C-x a' (`append-to-buffer') and `M-x insert-buffer' can be
584: used to copy text from one buffer to another. *Note Accumulating Text::.
585:
586:
587: File: emacs Node: Kill Buffer, Prev: Misc Buffer, Up: Buffers, Next: Several Buffers
588:
589: Killing Buffers
590: ===============
591:
592: After you use Emacs for a while, you may accumulate a large number of
593: buffers. You may then find it convenient to eliminate the ones you no
594: longer need. There are several commands provided for doing this.
595:
596: `C-x k'
597: Kill a buffer, specified by name (`kill-buffer').
598: `M-x kill-some-buffers'
599: Offer to kill each buffer, one by one.
600:
601:
602: `C-x k' (`kill-buffer') kills one buffer, whose name you specify
603: in the minibuffer. The default, used if you type just RET in the
604: minibuffer, is to kill the current buffer. If the current buffer is
605: killed, another buffer is selected; a buffer that has been selected
606: recently but does not appear in any window now is chosen to be selected.
607: If the buffer being killed is modified (has unsaved editing) then you are
608: asked to confirm with `yes' before the buffer is killed.
609:
610: The command `M-x kill-some-buffers' asks about each buffer, one by
611: one. An answer of `y' means to kill the buffer. Killing the current
612: buffer or a buffer containing unsaved changes selects a new buffer or asks
613: for confirmation just like `kill-buffer'.
614:
615:
616: File: emacs Node: Several Buffers, Prev: Kill Buffer, Up: Buffers
617:
618: Operating on Several Buffers
619: ============================
620:
621: The "buffer-menu" facility is like a "Dired for buffers"; it allows
622: you to request operations on various Emacs buffers by editing an Emacs
623: buffer containing a list of them. You can save buffers, kill them
624: (here called "deleting" them, for consistency with Dired), or display
625: them.
626:
627: `M-x buffer-menu'
628: Begin editing a buffer listing all Emacs buffers.
629:
630: The command `buffer-menu' writes a list of all Emacs buffers into
631: the buffer `*Buffer List*', and selects that buffer in Buffer Menu
632: mode. The buffer is read-only, and can only be changed through the special
633: commands described in this section. Most of these commands are graphic
634: characters. The usual Emacs cursor motion commands can be used in the
635: `*Buffer List*' buffer. The following special commands apply to the
636: buffer described on the current line.
637:
638: `d'
639: Request to delete (kill) the buffer, then move down. The request
640: shows as a `D' on the line, before the buffer name. Requested
641: deletions take place when the `x' command is used.
642: `k'
643: Synonym for `d'.
644: `C-d'
645: Like `d' but move up afterwards instead of down.
646: `s'
647: Request to save the buffer. The request shows as an `S' on the
648: line. Requested saves take place when the `x' command is used.
649: You may request both saving and deletion for the same buffer.
650: `~'
651: Mark buffer "unmodified". The command `~' does this
652: immediately when typed.
653: `x'
654: Perform previously requested deletions and saves.
655: `u'
656: Remove any request made for the current line, and move down.
657: `DEL'
658: Move to previous line and remove any request made for that line.
659:
660: All the commands that put in or remove flags to request later operations
661: also move down a line, and accept a numeric argument as a repeat count,
662: unless otherwise specified.
663:
664: There are also special commands to use the buffer list to select another
665: buffer, and to specify one or more other buffers for display in additional
666: windows.
667:
668: `1'
669: Select the buffer in a full-screen window. This command takes effect
670: immediately.
671: `2'
672: Immediately set up two windows, with this buffer in one, and the
673: previously selected buffer (aside from the buffer `*Buffer List*')
674: in the other.
675: `f'
676: Immediately select the buffer in place of the `*Buffer List*' buffer.
677: `o'
678: Immediately select the buffer in another window as if by `C-x 4 b',
679: leaving `*Buffer List*' visible.
680: `q'
681: Immediately select this buffer, and also display in other windows any
682: buffers previously flagged with the `m' command. If there are no
683: such buffers, this command is equivalent to `1'.
684: `m'
685: Flag this buffer to be displayed in another window if the `q'
686: command is used. The request shows as a `>' at the beginning of
687: the line. The same buffer may not have both a delete request and a
688: display request.
689:
690: All that `buffer-menu' does directly is create and select a suitable
691: buffer, and turn on Buffer Menu mode. Everything else described above is
692: implemented by the special commands provided in Buffer Menu mode. One
693: consequence of this is that you can switch from the `*Buffer List*'
694: buffer to another Emacs buffer, and edit there. You can reselect the
695: `buffer-menu' buffer later, to perform the operations already
696: requested, or you can kill it, or pay no further attention to it.
697:
698: The only difference between `buffer-menu' and `list-buffers' is
699: that `buffer-menu' selects the `*Buffer List*' buffer and
700: `list-buffers' does not. If you run `list-buffers' (that is,
701: type `C-x C-b') and select the buffer list manually, you can use all of
702: the commands described here.
703:
704:
705: File: emacs Node: Windows, Prev: Buffers, Up: Top, Next: Major Modes
706:
707: Multiple Windows
708: ****************
709:
710: Emacs can split the screen into two or many windows, which can display
711: parts of different buffers, or different parts of one buffer.
712:
713: * Menu:
714:
715: * Basic Window:: Introduction to Emacs windows.
716: * Split Window:: New windows are made by splitting existing windows.
717: * Other Window:: Moving to another window or doing something to it.
718: * Pop Up Window:: Finding a file or buffer in another window.
719: * Change Window:: Deleting windows and changing their sizes.
720:
721:
722: File: emacs Node: Basic Window, Prev: Windows, Up: Windows, Next: Split Window
723:
724: Concepts of Emacs Windows
725: =========================
726:
727: When multiple windows are being displayed, each window has an Emacs
728: buffer designated for display in it. The same buffer may appear in more
729: than one window; if it does, any changes in its text are displayed in all
730: the windows where it appears. But the windows showing the same buffer can
731: show different parts of it, because each window has its own value of point.
732:
733: At any time, one of the windows is the "selected window"; the buffer
734: this window is displaying is the current buffer. The terminal's cursor
735: shows the location of point in this window. Each other window has a
736: location of point as well, but since the terminal has only one cursor there
737: is no way to show where those locations are.
738:
739: Commands to move point affect the value of point for the selected Emacs
740: window only. They do not change the value of point in any other Emacs
741: window, even one showing the same buffer. The same is true for commands
742: such as `C-x b' to change the selected buffer in the selected window;
743: they do not affect other windows at all. However, there are other commands
744: such as `C-x 4 b' that select a different window and switch buffers in
745: it. Also, all commands that display information in a window, including
746: (for example) `C-h f' (`describe-function') and `C-x C-b'
747: (`list-buffers'), work by switching buffers in a nonselected window
748: without affecting the selected window.
749:
750: Each window has its own mode line, which displays the buffer name,
751: modification status and major and minor modes of the buffer that is
752: displayed in the window. *Note Mode Line::, for full details on the mode
753: line.
754:
755:
756: File: emacs Node: Split Window, Prev: Basic Window, Up: Windows, Next: Other Window
757:
758: Splitting Windows
759: =================
760:
761: `C-x 2'
762: Split the selected window into two windows, one above the other
763: (`split-window-vertically').
764: `C-x 5'
765: Split the selected window into two windows positioned side by side
766: (`split-window-horizontally').
767:
768: The command `C-x 2' (`split-window-vertically') breaks the
769: selected window into two windows, one above the other. Both windows start
770: out displaying the same buffer, with the same value of point. By default
771: the two windows each get half the height of the window that was split; a
772: numeric argument specifies how many lines to give to the top window.
773:
774: `C-x 5' (`split-window-horizontally') breaks the selected
775: window into two side-by-side windows. A numeric argument specifies
776: how many columns to give the one on the left. A line of vertical bars
777: separates the two windows. Windows that are not the full width of the
778: screen have mode lines, but they are truncated; also, they do not
779: always appear in inverse video, because, the Emacs display routines
780: have not been taught how to display a region of inverse video that is
781: only part of a line on the screen.
782:
783: When a window is less than the full width, text lines too long to fit are
784: frequent. Continuing all those lines might be confusing. The variable
785: `truncate-partial-width-windows' can be set non-`nil' to force truncation
786: in all windows less than the full width of the screen, independent of the
787: buffer being displayed and its value for `truncate-lines'. *Note
788: Continuation Lines::.
789:
790: Horizontal scrolling is often used in side-by-side windows.
791: *Note Display::.
792:
793:
794: File: emacs Node: Other Window, Prev: Split Window, Up: Windows, Next: Pop Up Window
795:
796: Using Other Windows
797: ===================
798:
799: `C-x o'
800: Select another window (`other-window'). That is `o', not zero.
801: `C-M-v'
802: Scroll the next window (`scroll-other-window').
803: `M-x compare-windows'
804: Find next place where the text in the selected window does not match
805: the text in the next window.
806:
807: To select a different window, use `C-x o' (`other-window').
808: That is an `o', for `other', not a zero. When there are more than two
809: windows, this command moves through all the windows in a cyclic order,
810: generally top to bottom and left to right. From the rightmost and
811: bottommost window, it goes back to the one at the upper left corner. A
812: numeric argument means to move several steps in the cyclic order of
813: windows. A negative argument moves around the cycle in the opposite order.
814: When the minibuffer is active, the minibuffer is the last window in the
815: cycle; you can switch from the minibuffer window to one of the other
816: windows, and later switch back and finish supplying the minibuffer argument
817: that is requested. *Note Minibuffer Edit::.
818:
819: The usual scrolling commands (*Note Display::) apply to the selected
820: window only, but there is one command to scroll the next window.
821: `C-M-v' (`scroll-other-window') scrolls the window that `C-x o'
822: would select. It takes arguments, positive and negative, like `C-v'.
823:
824: The command `M-x compare-windows' compares the text in the current
825: window with that in the next window. Comparison starts at point in each
826: window. Point moves forward in each window, a character at a time in each
827: window, until the next characters in the two windows are different. Then
828: the command is finished.
829:
830:
831: File: emacs Node: Pop Up Window, Prev: Other Window, Up: Windows, Next: Change Window
832:
833: Displaying in Another Window
834: ============================
835:
836: `C-x 4' is a prefix key for commands that select another window
837: (splitting the window if there is only one) and select a buffer in that
838: window. Different `C-x 4' commands have different ways of finding the
839: buffer to select.
840:
841: `C-x 4 b BUFNAME RET'
842: Select buffer BUFNAME in another window. This runs
843: `switch-to-buffer-other-window'.
844: `C-x 4 f FILENAME RET'
845: Visit file FILENAME and select its buffer in another window. This
846: runs `find-file-other-window'. *Note Visiting::.
847: `C-x 4 d DIRECTORY RET'
848: Select a Dired buffer for directory DIRECTORY in another window.
849: This runs `dired-other-window'. *Note Dired::.
850: `C-x 4 m'
851: Start composing a mail message in another window. This runs
852: `mail-other-window', and its same-window version is `C-x m'
853: (*Note Sending Mail::).
854: `C-x 4 .'
855: Find a tag in the current tag table in another window. This runs
856: `find-tag-other-window', the multiple-window variant of `M-.'
857: (*Note Tags::).
858:
859:
860: File: emacs Node: Change Window, Prev: Pop Up Window, Up: Windows
861:
862: Deleting and Rearranging Windows
863: ================================
864:
865: `C-x 0'
866: Get rid of the selected window (`kill-window'). That is a zero.
867: `C-x 1'
868: Get rid of all windows except the selected one (`delete-other-windows').
869: `C-x ^'
870: Make the selected window taller, at the expense of the other(s)
871: (`enlarge-window').
872: `C-x }'
873: Make the selected window wider (`enlarge-window-horizontally').
874:
875: To delete a window, type `C-x 0' (`delete-window'). (That is a
876: zero.) The space occupied by the deleted window is distributed among the
877: other active windows (but not the minibuffer window, even if that is active
878: at the time). Once a window is deleted, its attributes are forgotten;
879: there is no automatic way to make another window of the same shape or
880: showing the same buffer. But the buffer continues to exist, and you can
881: select it in any window with `C-x b'.
882:
883: `C-x 1' (`delete-other-windows') is more powerful than `C-x 0';
884: it deletes all the windows except the selected one (and the minibuffer);
885: the selected window expands to use the whole screen except for the echo
886: area.
887:
888: To readjust the division of space among existing windows, use `C-x ^'
889: (`enlarge-window'). It makes the currently selected window get one
890: line bigger, or as many lines as is specified with a numeric argument.
891: With a negative argument, it makes the selected window smaller. `C-x
892: }' (`enlarge-window-horizontally') makes the selected window wider
893: by the specified number of columns. The extra screen space given to a
894: window comes from one of its neighbors, if that is possible; otherwise, all
895: the competing windows are shrunk in the same proportion. If this makes any
896: windows too small, those windows are deleted and their space is divided up.
897: The minimum size is specified by the variables `window-min-height' and
898: `window-min-width'.
899:
900:
901: File: emacs Node: Major Modes, Prev: Windows, Up: Top, Next: Indentation
902:
903: Major Modes
904: ***********
905:
906: Emacs has many different "major modes", each of which customizes
907: Emacs for editing text of a particular sort. The major modes are mutually
908: exclusive, and each buffer has one major mode at any time. The mode line
909: normally contains the name of the current major mode, in parentheses.
910: *Note Mode Line::.
911:
912: The least specialized major mode is called "Fundamental mode". This
913: mode has no mode-specific redefinitions or variable settings, so that each
914: Emacs command behaves in its most general manner, and each option is in its
915: default state. For editing any specific type of text, such as Lisp code or
916: English text, you should switch to the appropriate major mode, such as Lisp
917: mode or Text mode.
918:
919: Selecting a major mode changes the meanings of a few keys to become more
920: specifically adapted to the language being edited. The ones which are
921: changed frequently are TAB, DEL, and LFD. In addition,
922: the commands which handle comments use the mode to determine how comments
923: are to be delimited. Many major modes redefine the syntactical properties
924: of characters appearing in the buffer. *Note Syntax::.
925:
926: The major modes fall into three major groups. Lisp mode (which has
927: several variants), C mode and Muddle mode are for specific programming
928: languages. Text mode, Nroff mode, TeX mode and Outline mode are for
929: editing English text. The remaining major modes are not intended for use
930: on users' files; they are used in buffers created for specific purposes by
931: Emacs, such as Dired mode for buffers made by Dired (*Note Dired::), and
932: Mail mode for buffers made by `C-x m' (*Note Sending Mail::), and Shell
933: mode for buffers used for communicating with an inferior shell process
934: (*Note Interactive Shell::).
935:
936: Most programming language major modes specify that only blank lines
937: separate paragraphs. This is so that the paragraph commands remain useful.
938: *Note Paragraphs::. They also cause Auto Fill mode to use the definition of
939: TAB to indent the new lines it creates. This is because most lines
940: in a program are usually indented. *Note Indentation::.
941:
942: * Menu:
943:
944: * Choosing Modes:: How major modes are specified or chosen.
945:
946:
947: File: emacs Node: Choosing Modes, Prev: Major Modes, Up: Major Modes
948:
949: How Major Modes are Chosen
950: ==========================
951:
952: You can select a major mode explicitly for the current buffer, but
953: most of the time Emacs determines which mode to use based on the file
954: name or some text in the file.
955:
956: Explicit selection of a new major mode is done with a `M-x' command.
957: From the name of a major mode, add `-mode' to get the name of a
958: command to select that mode. Thus, you can enter Lisp mode by executing
959: `M-x lisp-mode'.
960:
961: When you visit a file, Emacs usually chooses the right major mode based
962: on the file's name. For example, files whose names end in `.c' are
963: edited in C mode. The correspondence between file names and major mode is
964: controlled by the variable `auto-mode-alist'. Its value is a list in
965: which each element has the form
966:
967: (REGEXP . MODE-FUNCTION)
968:
969: For example, one element normally found in the list has the form
970: `("\\.c$" . c-mode)', and it is responsible for selecting C mode
971: for files whose names end in `.c'. (Note that `\\' is needed in
972: Lisp syntax to include a `\' in the string, which is needed to
973: suppress the special meaning of `.' in regexps.) The only practical
974: way to change this variable is with Lisp code.
975:
976: You can specify which major mode should be used for editing a certain
977: file by a special sort of text in the first nonblank line of the file. The
978: mode name should appear in this line both preceded and followed by
979: `-*-'. Other text may appear on the line as well. For example,
980:
981: ;-*-Lisp-*-
982:
983: tells Emacs to use Lisp mode. Note how the semicolon is used to make Lisp
984: treat this line as a comment. Such an explicit specification overrides any
985: defaulting based on the file name.
986:
987: Another format of mode specification is
988:
989: -*-Mode: MODENAME;-*-
990:
991: which allows other things besides the major mode name to be specified.
992: However, Emacs does not look for anything except the mode name.
993:
994: The major mode can also be specified in a local variables list.
995: *Note File Variables::.
996:
997: When a file is visited that does not specify a major mode to use, or when
998: a new buffer is created with `C-x b', the major mode used is that
999: specified by the variable `default-major-mode'. Normally this value
1000: is the symbol `fundamental-mode', which specifies Fundamental mode.
1001: If `default-major-mode' is `nil', the major mode is taken from
1002: the previously selected buffer.
1003:
1004:
1005: File: emacs Node: Indentation, Prev: Major Modes, Up: Top, Next: Text
1006:
1007: Indentation
1008: ***********
1009:
1010: `TAB'
1011: Indent current line "appropriately" in a mode-dependent fashion.
1012: `LFD'
1013: Perform RET followed by TAB (`newline-and-indent').
1014: `M-^'
1015: Merge two lines (`delete-indentation'). This would cancel out
1016: the effect of LFD.
1017: `C-M-o'
1018: Split line at point; text on the line after point becomes a new line
1019: indented to the same column that it now starts in (`split-line').
1020: `M-m'
1021: Move (forward or back) to the first nonblank character on the current
1022: line (`back-to-indentation').
1023: `C-M-\'
1024: Indent several lines to same column (`indent-region').
1025: `C-x TAB'
1026: Shift block of lines rigidly right or left (`indent-rigidly').
1027: `M-i'
1028: Indent from point to the next prespecified tab stop column
1029: (`tab-to-tab-stop').
1030: `M-x indent-relative'
1031: Indent from point to under an indentation point in the previous line.
1032:
1033: Most programming languages have some indentation convention. For Lisp
1034: code, lines are indented according to their nesting in parentheses. The
1035: same general idea is used for C code, though many details are different.
1036:
1037: Whatever the language, to indent a line, use the TAB command. Each
1038: major mode defines this command to perform the sort of indentation
1039: appropriate for the particular language. In Lisp mode, TAB aligns
1040: the line according to its depth in parentheses. No matter where in the
1041: line you are when you type TAB, it aligns the line as a whole. In C
1042: mode, TAB implements a subtle and sophisticated indentation style that
1043: knows about many aspects of C syntax.
1044:
1045: In Text mode, TAB runs the command `tab-to-tab-stop', which
1046: indents to the next tab stop column. You can set the tab stops with
1047: `M-x edit-tab-stops'.
1048:
1049: * Menu:
1050:
1051: * Indentation Commands:: Various commands and techniques for indentation.
1052: * Tab Stops:: You can set arbitrary "tab stops" and then
1053: indent to the next tab stop when you want to.
1054: * Just Spaces:: You can request indentation using just spaces.
1055:
1056:
1057: File: emacs Node: Indentation Commands, Prev: Indentation, Up: Indentation, Next: Tab Stops
1058:
1059: Indentation Commands and Techniques
1060: ===================================
1061:
1062: If you just want to insert a tab character in the buffer, you can type
1063: `C-q TAB'.
1064:
1065: To move over the indentation on a line, do `Meta-m'
1066: (`back-to-indentation'). This command, given anywhere on a line,
1067: positions point at the first nonblank character on the line.
1068:
1069: To insert an indented line before the current line, do `C-a C-o
1070: TAB'. To make an indented line after the current line, use `C-e
1071: LFD'.
1072:
1073: `C-M-o' (`split-line') moves the text from point to the end of
1074: the line vertically down, so that the current line becomes two lines.
1075: `C-M-o' first moves point forward over any spaces and tabs. Then it
1076: inserts after point a newline and enough indentation to reach the same
1077: column point is on. Point remains before the inserted newline; in this
1078: regard, `C-M-o' resembles `C-o'.
1079:
1080: To join two lines cleanly, use the `Meta-^' (`delete-indentation')
1081: command to delete the indentation at the front of the current line, and the
1082: line boundary as well. They are replaced by a single space, or by no space
1083: if at the beginning of a line or before a `)' or after a `('. To
1084: delete just the indentation of a line, go to the beginning of the line and
1085: use `Meta-\' (`delete-horizontal-space'), which deletes all spaces
1086: and tabs around the cursor.
1087:
1088: There are also commands for changing the indentation of several lines at
1089: once. `Control-Meta-\' (`indent-region') gives each line which begins in
1090: the region the "usual" indentation by invoking TAB at the beginning of the
1091: line. A numeric argument specifies the column to indent to, and each line
1092: is shifted left or right so that its first nonblank character appears in
1093: that column. `C-x TAB' (`indent-rigidly') moves all of the lines in the
1094: region right by its argument (left, for negative arguments). The whole
1095: group of lines moves rigidly sideways, which is how the command gets its
1096: name.
1097:
1098: `M-x indent-relative' indents at point based on the previous line
1099: (actually, the last nonempty line.) It inserts whitespace at point, moving
1100: point, until it is underneath an indentation point in the previous line.
1101: An indentation point is the end of a sequence of whitespace or the end of
1102: the line. If point is farther right than any indentation point in the
1103: previous line, the whitespace before point is deleted and the first
1104: indentation point then applicable is used. If no indentation point is
1105: applicable even then, `tab-to-tab-stop' is run (see next section).
1106:
1107: `indent-relative' is the definition of TAB in Indented Text
1108: mode. *Note Text::.
1109:
1110:
1111: File: emacs Node: Tab Stops, Prev: Indentation Commands, Up: Indentation, Next: Just Spaces
1112:
1113: Tab Stops
1114: =========
1115:
1116: For typing in tables, you can use Text mode's definition of TAB,
1117: `tab-to-tab-stop'. This command inserts indentation before point,
1118: enough to reach the next tab stop column. If you are not in Text mode,
1119: this function can be found on `M-i' anyway.
1120:
1121: The tab stops used by `M-i' can be set arbitrarily by the user.
1122: They are stored in a variable called `tab-stop-list', as a list of
1123: column-numbers in increasing order.
1124:
1125: The convenient way to set the tab stops is using `M-x edit-tab-stops',
1126: which creates and selects a buffer containing a description of the tab stop
1127: settings. You can edit this buffer to specify different tab stops, and
1128: then type `C-c C-c' to make those new tab stops take effect. In the
1129: tab stop buffer, `C-c C-c' runs the function
1130: `edit-tab-stops-note-changes' rather than its usual definition
1131: `save-buffer'. `edit-tab-stops' records which buffer was current
1132: when you invoked it, and stores the tab stops back in that buffer; normally
1133: all buffers share the same tab stops and changing them in one buffer
1134: affects all, but if you happen to make `tab-stop-list' local in one
1135: buffer then `edit-tab-stops' in that buffer will edit the local
1136: settings.
1137:
1138: Here is what the text representing the tab stops looks like for ordinary
1139: tab stops every eight columns.
1140:
1141: : : : : : :
1142: 0 1 2 3 4
1143: 0123456789012345678901234567890123456789012345678
1144: To install changes, type C-c C-c
1145:
1146: The first line contains a colon at each tab stop. The remaining lines
1147: are present just to help you see where the colons are and know what to do.
1148:
1149: Note that the tab stops that control `tab-to-tab-stop' have nothing
1150: to do with displaying tab characters in the buffer. *Note Display Vars::,
1151: for more information on that.
1152:
1153:
This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.