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1 GNU Emacs NEWS -- history of user-visible changes. 2000-09-17
2 Copyright (C) 1999, 2000 Free Software Foundation, Inc.
3 See the end for copying conditions.
4
5 Please send Emacs bug reports to bug-gnu-emacs@gnu.org.
6 For older news, see the file ONEWS
7
8 \f
9 * Installation Changes in Emacs 21.1
10
11 ** Support for GNU/Linux on IA64 machines has been added.
12
13 ** Support for LynxOS has been added.
14
15 ** `movemail' defaults to supporting POP. You can turn this off using
16 the --without-pop configure option, should that be necessary.
17
18 ** There are new configure options associated with the support for
19 images and toolkit scrollbars. Use the --help option in `configure'
20 to list them.
21
22 ** There is a new configure option `--without-xim' that instructs
23 Emacs to not use X Input Methods (XIM), if these are available.
24
25 ** There is a new configure option `--disable-largefile' to omit
26 Unix-98-style support for large files if that is available.
27
28 ** You can build a 64-bit Emacs for SPARC/Solaris systems which
29 support 64-bit executables. See etc/MACHINES for instructions.
30
31 \f
32 * Changes in Emacs 21.1
33
34 ** The header line in an Info buffer is now displayed as an emacs header-line
35 (which is like a mode-line, but at the top of the window), so that it
36 remains visible even when the buffer has been scrolled. This behavior
37 may be disabled by customizing the option `Info-use-header-line'.
38
39 ** `gnus-user-agent' is a new possibility for `mail-user-agent'. It
40 is like `message-user-agent', but with all the Gnus paraphernalia.
41
42 +++
43 ** The recommended way of using Iswitchb is via the new global minor
44 mode `iswitchb-mode'.
45
46 ** Gnus changes.
47
48 The Gnus NEWS entries are short, but they reflect sweeping changes in
49 four areas: Article display treatment, MIME treatment,
50 internationalization and mail-fetching.
51
52 *** The mail-fetching functions have changed. See the manual for the
53 many details. In particular, all procmail fetching variables are gone.
54
55 If you used procmail like in
56
57 (setq nnmail-use-procmail t)
58 (setq nnmail-spool-file 'procmail)
59 (setq nnmail-procmail-directory "~/mail/incoming/")
60 (setq nnmail-procmail-suffix "\\.in")
61
62 this now has changed to
63
64 (setq mail-sources
65 '((directory :path "~/mail/incoming/"
66 :suffix ".in")))
67
68 More information is available in the info doc at Select Methods ->
69 Getting Mail -> Mail Sources
70
71 *** Gnus is now a MIME-capable reader. This affects many parts of
72 Gnus, and adds a slew of new commands. See the manual for details.
73
74 *** Gnus has also been multilingualized. This also affects too
75 many parts of Gnus to summarize here, and adds many new variables.
76
77 *** gnus-auto-select-first can now be a function to be
78 called to position point.
79
80 *** The user can now decide which extra headers should be included in
81 summary buffers and NOV files.
82
83 *** `gnus-article-display-hook' has been removed. Instead, a number
84 of variables starting with `gnus-treat-' have been added.
85
86 *** The Gnus posting styles have been redone again and now work in a
87 subtly different manner.
88
89 *** New web-based backends have been added: nnslashdot, nnwarchive
90 and nnultimate. nnweb has been revamped, again, to keep up with
91 ever-changing layouts.
92
93 *** Gnus can now read IMAP mail via nnimap.
94
95 *** There is image support.
96
97 ** When your terminal can't display characters from some of the ISO
98 8859 character sets but can display Latin-1, you can display
99 more-or-less mnemonic sequences of ASCII/Latin-1 characters instead of
100 empty boxes (under a window system) or question marks (not under a
101 window system). Customize the option `latin1-display' to turn this
102 on.
103
104 ** The new user-option `find-file-suppress-same-file-warnings' can be
105 set to suppress warnings ``X and Y are the same file'' when visiting a
106 file that is already visited under a different name.
107
108 ** The new user-option `electric-help-shrink-window' can be set to
109 nil to prevent adjusting the help window size to the buffer size.
110
111 ** Emacs now checks for recursive loads of Lisp files. If the
112 recursion depth exceeds `recursive-load-depth-limit', an error is
113 signaled.
114
115 ** The Strokes package has been updated. If your Emacs has XPM
116 support, you can use it for pictographic editing. In Strokes mode,
117 use C-mouse-2 to compose a complex stoke and insert it into the
118 buffer. You can encode or decode a strokes buffer with new commands
119 M-x strokes-encode-buffer and M-x strokes-decode-buffer. There is a
120 new command M-x strokes-list-strokes.
121
122 +++
123 ** New command M-x describe-character-set reads a character set name
124 and displayes information about that.
125
126 ** When an error is signaled during the loading of the user's init
127 file, Emacs now pops up the *Messages* buffer.
128
129 ** Polish and German translations of Emacs' reference card have been
130 added. They are named `pl-refcard.tex' and `de-refcard.tex'.
131 Postscript files are included.
132
133 ** A reference card for Dired has been added. Its name is
134 `dired-ref.tex'.
135
136 ** The new variable `auto-mode-interpreter-regexp' contains a regular
137 expression matching interpreters, for file mode determination.
138
139 This regular expression is matched against the first line of a file to
140 determine the file's mode in `set-auto-mode' when Emacs can't deduce a
141 mode from the file's name. If it matches, the file is assumed to be
142 interpreted by the interpreter matched by the second group of the
143 regular expression. The mode is then determined as the mode
144 associated with that interpreter in `interpreter-mode-alist'.
145
146 +++
147 ** C-down-mouse-3 is bound differently. Now if the menu bar is not
148 displayed it pops up a menu containing the items which would be on the
149 menu bar. If the menu bar is displayed, it pops up the major mode
150 menu or the Edit menu if there is no major mode menu.
151
152 ** Variable `load-path' is no longer customizable because it contains
153 a version-dependent component.
154
155 ** The <delete> function key is now bound to `delete-char' by default.
156 Note that this takes effect only on window systems. On TTYs, Emacs
157 will receive ASCII 127 when the DEL key is pressed. This
158 character is still bound as before.
159
160 ** Item Save Options on the Options menu allows saving options set
161 using that menu.
162
163 ** New function executable-make-buffer-file-executable-if-script-p is
164 suitable as an after-save-hook as an alternative to `executable-chmod'.
165
166 +++
167 ** The most preferred coding-system is now used to save a buffer if
168 buffer-file-coding-system is `undecided' and it is safe for the buffer
169 contents. (The most preferred is set by set-language-environment or
170 by M-x prefer-coding-system.) Thus if you visit an ASCII file and
171 insert a non-ASCII character from your current language environment,
172 the file will be saved silently with the appropriate coding.
173 Previously you would be prompted for a safe coding system.
174
175 +++
176 ** New variable `inhibit-iso-escape-detection' determines if Emacs'
177 coding system detection algorithm should pay attention to ISO2022's
178 escape sequences. If this variable is non-nil, the algorithm ignores
179 such escape sequences. The default value is nil, and it is
180 recommended not to change it except for the special case that you
181 always want to read any escape code verbatim. If you just want to
182 read a specific file without decoding escape codes, use C-x RET c
183 (`universal-coding-system-argument'). For instance, C-x RET c latin-1
184 RET C-x C-f filename RET.
185
186 ** Variable `default-korean-keyboard' is initialized properly from the
187 environment variable `HANGUL_KEYBOARD_TYPE'.
188
189 +++
190 ** C-u C-x = provides detailed information about the character at
191 point in a pop-up window.
192
193 +++
194 ** New command M-x list-charset-chars reads a character set name and
195 displays all characters in that character set.
196
197 ** M-x set-terminal-coding-system (C-x RET t) now allows CCL-based
198 coding systems such as cpXXX and cyrillic-koi8.
199
200 +++
201 ** M-; now calls comment-dwim which tries to do something clever based
202 on the context. M-x kill-comment is now an alias to comment-kill,
203 defined on newcomment.el.
204
205 +++
206 ** The function `getenv' is now callable interactively.
207
208 ** The many obsolete language `setup-...-environment' commands have
209 been removed -- use `set-language-environment'.
210
211 +++
212 ** New user options `display-time-mail-face' and
213 `display-time-use-mail-icon' control the appearance of mode-line mail
214 indicator used by the display-time package. On a suitable display the
215 indicator can be an icon and is mouse-sensitive.
216
217 +++
218 ** Emacs' auto-save list files are now by default stored in a
219 sub-directory `.emacs.d/auto-save-list/' of the user's home directory.
220 (On MS-DOS, this subdirectory's name is `_emacs.d/auto-save.list/'.)
221 You can customize `auto-save-list-prefix' to change this location.
222
223 +++
224 ** On window-systems, additional space can be put between text lines
225 on the display using several methods
226
227 +++
228 - By setting frame parameter `line-spacing' to PIXELS. PIXELS must be
229 a positive integer, and specifies that PIXELS number of pixels should
230 be put below text lines on the affected frame or frames.
231
232 +++
233 - By setting X resource `lineSpacing', class `LineSpacing'. This is
234 equivalent ot specifying the frame parameter.
235
236 - By specifying `--line-spacing=N' or `-lsp N' on the command line.
237
238 - By setting buffer-local variable `line-spacing'. The meaning is
239 the same, but applies to the a particular buffer only.
240
241 +++
242 ** The new command `clone-indirect-buffer' can be used to create
243 an indirect buffer that is a twin copy of the current buffer. The
244 command `clone-indirect-buffer-other-window', bound to C-x 4 c,
245 does the same but displays the indirect buffer in another window.
246
247 +++
248 ** New user options `backup-directory-alist' and
249 `make-backup-file-name-function' control the placement of backups,
250 typically in a single directory or in an invisible sub-directory.
251
252 ** New commands iso-iso2sgml and iso-sgml2iso convert between Latin-1
253 characters and the corresponding SGML (HTML) entities.
254
255 +++
256 ** Emacs now refuses to load compiled Lisp files which weren't
257 compiled with Emacs. Set `load-dangerous-libraries' to t to change
258 this behavior.
259
260 The reason for this change is an incompatible change in XEmacs' byte
261 compiler. Files compiled with XEmacs can contain byte codes that let
262 Emacs dump core.
263
264 +++
265 ** New X resources recognized
266
267 *** The X resource `synchronous', class `Synchronous', specifies
268 whether Emacs should run in synchronous mode. Synchronous mode
269 is useful for debugging X problems.
270
271 Example:
272
273 emacs.synchronous: true
274
275 *** The X resource `visualClass, class `VisualClass', specifies the
276 visual Emacs should use. The resource's value should be a string of
277 the form `CLASS-DEPTH', where CLASS is the name of the visual class,
278 and DEPTH is the requested color depth as a decimal number. Valid
279 visual class names are
280
281 TrueColor
282 PseudoColor
283 DirectColor
284 StaticColor
285 GrayScale
286 StaticGray
287
288 Visual class names specified as X resource are case-insensitive, i.e.
289 `pseudocolor', `Pseudocolor' and `PseudoColor' all have the same
290 meaning.
291
292 The program `xdpyinfo' can be used to list the visual classes
293 supported on your display, and which depths they have. If
294 `visualClass' is not specified, Emacs uses the display's default
295 visual.
296
297 Example:
298
299 emacs.visualClass: TrueColor-8
300
301 *** The X resource `privateColormap', class `PrivateColormap',
302 specifies that Emacs should use a private colormap if it is using the
303 default visual, and that visual is of class PseudoColor. Recognized
304 resource values are `true' or `on'.
305
306 Example:
307
308 emacs.privateColormap: true
309
310 ** The menu bar configuration has changed. The new configuration is
311 more CUA-compliant. The most significant change is that Options is
312 now a separate menu-bar item, with Mule and Customize as its submenus.
313
314 ** User-option `show-cursor-in-non-selected-windows' controls how to
315 display the cursor in non-selected windows. If nil, no cursor is
316 shown, if non-nil a hollow box cursor is shown. This option can
317 be customized.
318
319 +++
320 ** The variable `echo-keystrokes' may now have a floating point value.
321
322 +++
323 ** C-x 5 1 runs the new command delete-other-frames which deletes
324 all frames except the selected one.
325
326 ** If your init file is compiled (.emacs.elc), `user-init-file' is set
327 to the source name (.emacs.el), if that exists, after loading it.
328
329 ** The help string specified for a menu-item whose definition contains
330 the property `:help HELP' is now displayed under X, on MS-Windows, and
331 MS-DOS, either in the echo area or with tooltips. Many standard menus
332 displayed by Emacs now have help strings.
333
334 +++
335 ** Highlighting of mouse-sensitive regions is now supported in the
336 MS-DOS version of Emacs.
337
338 ** New user option `read-mail-command' specifies a command to use to
339 read mail from the menu etc.
340
341 +++
342 ** Hexl contains a new command `hexl-insert-hex-string' which inserts
343 a string of hexadecimal numbers read from the mini-buffer.
344
345 ** Changes in Texinfo mode.
346
347 ** A couple of new key bindings have been added for inserting Texinfo
348 macros
349
350 Key binding Macro
351 -------------------------
352 C-c C-c C-s @strong
353 C-c C-c C-e @emph
354 C-c C-c u @url
355 C-c C-c q @quotation
356 C-c C-c m @email
357
358 ** Changes in Outline mode.
359
360 There is now support for Imenu to index headings. A new command
361 `outline-headers-as-kill' copies the visible headings in the region to
362 the kill ring, e.g. to produce a table of contents.
363
364 ** Changes to Emacs Server
365
366 +++
367 *** The new option `server-kill-new-buffers' specifies what to do
368 with buffers when done with them. If non-nil, the default, buffers
369 are killed, unless they were already present before visiting them with
370 Emacs Server. If nil, `server-temp-file-regexp' specifies which
371 buffers to kill, as before.
372
373 Please note that only buffers are killed that still have a client,
374 i.e. buffers visited with `emacsclient --no-wait' are never killed in
375 this way.
376
377 ** Changes to Show Paren mode.
378
379 *** Overlays used by Show Paren mode now use a priority property.
380 The new user option show-paren-priority specifies the priority to
381 use. Default is 1000.
382
383 +++
384 ** New command M-x check-parens can be used to find unbalanced paren
385 groups and strings in buffers in Lisp mode (or other modes).
386
387 +++
388 ** You can now easily create new *Info* buffers using either
389 M-x clone-buffer, C-u m <entry> RET or C-u g <entry> RET.
390 M-x clone-buffer can also be used on *Help* and several other special
391 buffers.
392
393 +++
394 ** Emacs can now support 'wheeled' mice (such as the MS IntelliMouse)
395 under XFree86. To enable this, simply put (mwheel-install) in your
396 .emacs file.
397
398 The variables `mwheel-follow-mouse' and `mwheel-scroll-amount'
399 determine where and by how much buffers are scrolled.
400
401 ** Listing buffers with M-x list-buffers (C-x C-b) now shows
402 abbreviated file names. Abbreviations can be customized by changing
403 `directory-abbrev-alist'.
404
405 ** Faces and frame parameters.
406
407 There are four new faces `scroll-bar', `border', `cursor' and `mouse'.
408 Setting the frame parameters `scroll-bar-foreground' and
409 `scroll-bar-background' sets foreground and background color of face
410 `scroll-bar' and vice versa. Setting frame parameter `border-color'
411 sets the background color of face `border' and vice versa. Likewise
412 for frame parameters `cursor-color' and face `cursor', and frame
413 parameter `mouse-color' and face `mouse'.
414
415 Changing frame parameter `font' sets font-related attributes of the
416 `default' face and vice versa. Setting frame parameters
417 `foreground-color' or `background-color' sets the colors of the
418 `default' face and vice versa.
419
420 +++
421 ** New face `menu'.
422
423 The face `menu' can be used to change colors and font of Emacs' menus.
424 Setting the font of LessTif/Motif menus is currently not supported;
425 attempts to set the font are ignored in this case.
426
427 +++
428 ** New frame parameter `screen-gamma' for gamma correction.
429
430 The new frame parameter `screen-gamma' specifies gamma-correction for
431 colors. Its value may be nil, the default, in which case no gamma
432 correction occurs, or a number > 0, usually a float, that specifies
433 the screen gamma of a frame's display.
434
435 PC monitors usually have a screen gamma of 2.2. smaller values result
436 in darker colors. You might want to try a screen gamma of 1.5 for LCD
437 color displays. The viewing gamma Emacs uses is 0.4545. (1/2.2).
438
439 The X resource name of this parameter is `screenGamma', class
440 `ScreenGamma'.
441
442 ** Emacs has a new redisplay engine.
443
444 The new redisplay handles characters of variable width and height.
445 Italic text can be used without redisplay problems. Fonts containing
446 oversized characters, i.e. characters larger than the logical height
447 of a font can be used. Images of various formats can be displayed in
448 the text.
449
450 ** Emacs has a new face implementation.
451
452 The new faces no longer fundamentally use X font names to specify the
453 font. Instead, each face has several independent attributes--family,
454 height, width, weight and slant--that it may or may not specify.
455 These attributes can be merged from various faces, and then together
456 specify a font.
457
458 Faces are supported on terminals that can display color or fonts.
459 These terminal capabilities are auto-detected. Details can be found
460 under Lisp changes, below.
461
462 ** New default font is Courier 12pt.
463
464 +++
465 ** When using a windowing terminal, each Emacs window now has a cursor
466 of its own. When the window is selected, the cursor is solid;
467 otherwise, it is hollow.
468
469 ** Bitmap areas to the left and right of windows are used to display
470 truncation marks, continuation marks, overlay arrows and alike. The
471 foreground, background, and stipple of these areas can be changed by
472 customizing face `fringe'.
473
474 ** The mode line under X is now drawn with shadows by default. You
475 can change its appearance by modifying the face `modeline'.
476
477 ** LessTif support.
478
479 Emacs now runs with the LessTif toolkit (see <http://www.lesstif.org>).
480 You will need a version 0.88.1 or later.
481
482 ** Toolkit scroll bars.
483
484 Emacs now uses toolkit scrollbars if available. When configured for
485 LessTif/Motif, it will use that toolkit's scrollbar. Otherwise, when
486 configured for Lucid and Athena widgets, it will use the Xaw3d scroll
487 bar if Xaw3d is available. You can turn off the use of toolkit scroll
488 bars by specifying `--with-toolkit-scroll-bars=no' when configuring
489 Emacs.
490
491 When you encounter problems with the Xaw3d scroll bar, watch out how
492 Xaw3d is compiled on your system. If the Makefile generated from
493 Xaw3d's Imakefile contains a `-DNARROWPROTO' compiler option, and your
494 Emacs system configuration file `s/your-system.h' does not contain a
495 define for NARROWPROTO, you might consider adding it. Take
496 `s/freebsd.h' as an example.
497
498 Alternatively, if you don't have access to the Xaw3d source code, take
499 a look at your system's imake configuration file, for example in the
500 directory `/usr/X11R6/lib/X11/config' (paths are different on
501 different systems). You will find files `*.cf' there. If your
502 system's cf-file contains a line like `#define NeedWidePrototypes NO',
503 add a `#define NARROWPROTO' to your Emacs system configuration file.
504
505 The reason for this is that one Xaw3d function uses `double' or
506 `float' function parameters depending on the setting of NARROWPROTO.
507 This is not a problem when Imakefiles are used because each system's
508 image configuration file contains the necessary information. Since
509 Emacs doesn't use imake, this has do be done manually.
510
511 ** Toggle buttons and radio buttons in menus.
512
513 When compiled with LessTif (or Motif) support, Emacs uses toolkit
514 widgets for radio and toggle buttons in menus. When configured for
515 Lucid, Emacs draws radio buttons and toggle buttons similar to Motif.
516
517 +++
518 ** Highlighting of trailing whitespace.
519
520 When `show-trailing-whitespace' is non-nil, Emacs displays trailing
521 whitespace in the face `trailing-whitespace'. Trailing whitespace is
522 defined as spaces or tabs at the end of a line. To avoid busy
523 highlighting when entering new text, trailing whitespace is not
524 displayed if point is at the end of the line containing the
525 whitespace.
526
527 +++
528 ** Busy-cursor.
529
530 Emacs can optionally display a busy-cursor under X. You can turn the
531 display on or off by customizing group `cursor'.
532
533 +++
534 ** Blinking cursor
535
536 M-x blink-cursor-mode toggles a blinking cursor under X and on
537 terminals having terminal capabilities `vi', `vs', and `ve'. Blinking
538 and related parameters like frequency and delay can be customized in
539 the group `cursor'.
540
541 ** New font-lock support mode `jit-lock-mode'.
542
543 This support mode is roughly equivalent to `lazy-lock' but is
544 generally faster. It supports stealth and deferred fontification.
545 See the documentation of the function `jit-lock-mode' for more
546 details.
547
548 Font-lock uses jit-lock-mode as default support mode, so you don't
549 have to do anything to activate it.
550
551 ** Tabs and variable-width text.
552
553 Tabs are now displayed with stretch properties; the width of a tab is
554 defined as a multiple of the normal character width of a frame, and is
555 independent of the fonts used in the text where the tab appears.
556 Thus, tabs can be used to line up text in different fonts.
557
558 ** Enhancements of the Lucid menu bar
559
560 +++
561 *** The Lucid menu bar now supports the resource "margin".
562
563 emacs.pane.menubar.margin: 5
564
565 The default margin is 4 which makes the menu bar appear like the
566 LessTif/Motif one.
567
568 *** Arrows that indicate sub-menus are now drawn with shadows, as in
569 LessTif and Motif.
570
571 +++
572 ** Hscrolling in C code.
573
574 Horizontal scrolling now happens automatically if
575 `automatic-hscrolling' is set (the default). This setting can be
576 customized.
577
578 ** Tool bar support.
579
580 Emacs supports a tool bar at the top of a frame under X. For details
581 how to define a tool bar, see the page describing Lisp-level changes.
582 Tool-bar global minor mode controls whether or not it is displayed.
583 To make the tool bar more useful, we need contributions of extra icons
584 for specific modes (with copyright assignments).
585
586 +++
587 ** Mouse-sensitive mode line.
588
589 Different parts of the mode line under X have been made
590 mouse-sensitive. Moving the mouse to a mouse-sensitive part in the mode
591 line changes the appearance of the mouse pointer to an arrow, and help
592 about available mouse actions is displayed either in the echo area, or
593 in the tooltip window if you have enabled one.
594
595 Currently, the following actions have been defined:
596
597 - Mouse-1 on the buffer name in the mode line switches between two
598 buffers.
599
600 - Mouse-2 on the buffer-name switches to the next buffer, and
601 M-mouse-2 switches to the previous buffer in the buffer list.
602
603 - Mouse-3 on the buffer-name displays a buffer menu.
604
605 - Mouse-2 on the read-only or modified status in the mode line (`%' or
606 `*') toggles the status.
607
608 - Mouse-3 on the mode name display a minor-mode menu.
609
610 ** LessTif/Motif file selection dialog.
611
612 When Emacs is configured to use LessTif or Motif, reading a file name
613 from a menu will pop up a file selection dialog if `use-dialog-box' is
614 non-nil.
615
616 ** Emacs can display faces on TTY frames.
617
618 Emacs automatically detects terminals that are able to display colors.
619 Faces with a weight greater than normal are displayed extra-bright, if
620 the terminal supports it. Faces with a weight less than normal and
621 italic faces are displayed dimmed, if the terminal supports it.
622 Underlined faces are displayed underlined if possible. Other face
623 attributes such as `overline', `strike-through', and `box' are ignored
624 on terminals.
625
626 ** Sound support
627
628 Emacs supports playing sound files on GNU/Linux and FreeBSD (Voxware
629 driver and native BSD driver, a.k.a. Luigi's driver). Currently
630 supported file formats are RIFF-WAVE (*.wav) and Sun Audio (*.au).
631
632 +++
633 ** A new variable, backup-by-copying-when-privileged-mismatch, gives
634 the highest file uid for which backup-by-copying-when-mismatch will be
635 forced on. The assumption is that uids less than or equal to this
636 value are special uids (root, bin, daemon, etc.--not real system
637 users) and that files owned by these users should not change ownership,
638 even if your system policy allows users other than root to edit them.
639
640 The default is 200; set the variable to nil to disable the feature.
641
642 +++
643 ** A block cursor can be drawn as wide as the glyph under it under X.
644
645 As an example: if a block cursor is over a tab character, it will be
646 drawn as wide as that tab on the display. To do this, set
647 `x-stretch-cursor' to a non-nil value.
648
649 +++
650 ** Empty display lines at the end of a buffer may be marked with a
651 bitmap (this is similar to the tilde displayed by vi).
652
653 This behavior is activated by setting the buffer-local variable
654 `indicate-empty-lines' to a non-nil value. The default value of this
655 variable is found in `default-indicate-empty-lines'.
656
657 +++
658 ** There is a new "aggressive" scrolling method.
659
660 When scrolling up because point is above the window start, if the
661 value of the buffer-local variable `scroll-up-aggessively' is a
662 number, Emacs chooses a new window start so that point ends up that
663 fraction of the window's height from the top of the window.
664
665 When scrolling down because point is below the window end, if the
666 value of the buffer-local variable `scroll-down-aggessively' is a
667 number, Emacs chooses a new window start so that point ends up that
668 fraction of the window's height from the bottom of the window.
669
670 ** The rectangle commands now avoid inserting undesirable spaces,
671 notably at the end of lines.
672
673 All these functions have been rewritten to avoid inserting unwanted
674 spaces, and an optional prefix now allows them to behave the old way.
675
676 +++
677 There is a new command M-x replace-rectangle.
678
679 ** The new command M-x query-replace-regexp-eval acts like
680 query-replace-regexp, but takes a Lisp expression which is evaluated
681 after each match to get the replacement text.
682
683 +++
684 ** M-x query-replace recognizes a new command `e' (or `E') that lets
685 you edit the replacement string.
686
687 ** The new command mail-abbrev-complete-alias, bound to `M-TAB', lets
688 you complete mail aliases in the text, analogous to
689 lisp-complete-symbol.
690
691 +++
692 ** Emacs now resizes mini-windows if appropriate.
693
694 If a message is longer than one line, or minibuffer contents are
695 longer than one line, Emacs now resizes the minibuffer window unless
696 it is on a frame of its own. You can control the maximum minibuffer
697 window size by setting the following variable:
698
699 - User option: max-mini-window-height
700
701 Maximum height for resizing mini-windows. If a float, it specifies a
702 fraction of the mini-window frame's height. If an integer, it
703 specifies a number of lines. If nil, don't resize.
704
705 Default is 0.25.
706
707 ** The command `Info-search' now uses a search history.
708
709 ** Changes to hideshow.el
710
711 Hideshow is now at version 5.x. It uses a new algorithms for block
712 selection and traversal, includes more isearch support, and has more
713 conventional keybindings.
714
715 *** Generalized block selection and traversal
716
717 A block is now recognized by three things: its start and end regexps
718 (both strings), and a match-data selector (an integer) specifying
719 which sub-expression in the start regexp serves as the place where a
720 `forward-sexp'-like function can operate. Hideshow always adjusts
721 point to this sub-expression before calling `hs-forward-sexp-func'
722 (which for most modes evaluates to `forward-sexp').
723
724 If the match-data selector is not specified, it defaults to zero,
725 i.e., the entire start regexp is valid, w/ no prefix. This is
726 backwards compatible with previous versions of hideshow. Please see
727 the docstring for variable `hs-special-modes-alist' for details.
728
729 *** Isearch support for updating mode line
730
731 During incremental search, if Hideshow minor mode is active, hidden
732 blocks are temporarily shown. The variable `hs-headline' records the
733 line at the beginning of the opened block (preceding the hidden
734 portion of the buffer), and the mode line is refreshed. When a block
735 is re-hidden, the variable is set to nil.
736
737 To show `hs-headline' in the mode line, you may wish to include
738 something like this in your .emacs.
739
740 (add-hook 'hs-minor-mode-hook
741 (lambda ()
742 (add-to-list 'mode-line-format 'hs-headline)))
743
744 *** New customization var: `hs-hide-all-non-comment-function'
745
746 Normally, `hs-hide-all' hides everything, leaving only the
747 header lines of top-level forms (and comments, unless var
748 `hs-hide-comments-when-hiding-all' is non-nil). It does this by
749 moving point to each top-level block beginning and hiding the
750 block there. In some major modes (for example, Java), this
751 behavior results in few blocks left visible, which may not be so
752 useful.
753
754 You can now set var `hs-hide-all-non-comment-function' to a
755 function to be called at each top-level block beginning, instead
756 of the normal block-hiding function. For example, the following
757 code defines a function to hide one level down and move point
758 appropriately, and then tells hideshow to use the new function.
759
760 (defun ttn-hs-hide-level-1 ()
761 (hs-hide-level 1)
762 (forward-sexp 1))
763 (setq hs-hide-all-non-comment-function 'ttn-hs-hide-level-1)
764
765 The name `hs-hide-all-non-comment-function' was chosen to
766 emphasize that this function is not called for comment blocks,
767 only for code blocks.
768
769 *** Command deleted: `hs-show-region'
770
771 Historical Note: This command was added to handle "unbalanced
772 parentheses" emergencies back when hideshow.el used selective
773 display for implementation.
774
775 *** Commands rebound to more conventional keys
776
777 The hideshow commands used to be bound to keys of the form "C-c
778 LETTER". This is contrary to the Emacs keybinding convention,
779 which reserves that space for user modification. Here are the
780 new bindings (which includes the addition of `hs-toggle-hiding'):
781
782 hs-hide-block C-c C-h
783 hs-show-block C-c C-s
784 hs-hide-all C-c C-M-h
785 hs-show-all C-c C-M-s
786 hs-hide-level C-c C-l
787 hs-toggle-hiding C-c C-c
788 hs-mouse-toggle-hiding [(shift button-2)]
789
790 These were chosen to roughly imitate those used by Outline mode.
791
792 ** Changes to Change Log mode and Add-Log functions
793
794 +++
795 *** If you invoke `add-change-log-entry' from a backup file, it makes
796 an entry appropriate for the file's parent. This is useful for making
797 log entries by comparing a version with deleted functions.
798
799 +++
800 **** New command M-x change-log-merge merges another log into the
801 current buffer.
802
803 +++
804 *** New command M-x change-log-redate fixes any old-style date entries
805 in a log file.
806
807 +++
808 *** Change Log mode now adds a file's version number to change log
809 entries if user-option `change-log-version-info-enabled' is non-nil.
810
811 +++
812 *** Unless the file is under version control the search for a file's
813 version number is performed based on regular expressions from
814 `change-log-version-number-regexp-list' which can be cutomized.
815 Version numbers are only found in the first 10 percent of a file.
816
817 *** Change Log mode now defines its own faces for font-lock
818 highlighting.
819
820 ** Changes in Font Lock
821
822 *** The new function `font-lock-remove-keywords' can be used to remove
823 font-lock keywords from the current buffer or from a specific major
824 mode.
825
826 ** Comint (subshell) changes
827
828 By default, comint no longer uses the variable `comint-prompt-regexp' to
829 distiguish prompts from user-input. Instead, it notices which parts of
830 the text were output by the process, and which entered by the user, and
831 attaches `field' properties to allow emacs commands to use this information.
832 Common movement commands, notably beginning-of-line, respect field
833 boundaries in a fairly natural manner.
834 To disable this feature, and use the old behavior, set the variable
835 `comint-use-prompt-regexp-instead-of-fields' to a non-nil value.
836
837 Comint now includes new features to send commands to running processes
838 and redirect the output to a designated buffer or buffers.
839
840 The command M-x comint-redirect-send-command reads a command and
841 buffer name from the mini-buffer. The command is sent to the current
842 buffer's process, and its output is inserted into the specified buffer.
843
844 The command M-x comint-redirect-send-command-to-process acts like
845 M-x comint-redirect-send-command but additionally reads the name of
846 the buffer whose process should be used from the mini-buffer.
847
848 Packages based on comint.el like shell-mode, and scheme-interaction-mode
849 now highlight user input and program prompts, and support choosing
850 previous input with mouse-2. To control these feature, see the
851 user-options `comint-highlight-input' and `comint-highlight-prompt'.
852
853 ** Changes to Rmail mode
854
855 *** The new user-option rmail-rmail-user-mail-address-regexp can be
856 set to fine tune the identification of of the correspondent when
857 receiving new mail. If it matches the address of the sender, the
858 recipient is taken as correspondent of a mail. If nil, the default,
859 `user-login-name' and `user-mail-address' are used to exclude yourself
860 as correspondent.
861
862 Usually you don't have to set this variable, except if you collect
863 mails sent by you under different user names. Then it should be a
864 regexp matching your mail addresses.
865
866 *** The new user-option rmail-confirm-expunge controls whether and how
867 to ask for confirmation before expunging deleted messages from an
868 Rmail file. You can choose between no confirmation, confirmation
869 with y-or-n-p, or confirmation with yes-or-no-p. Default is to ask
870 for confirmation with yes-or-no-p.
871
872 *** RET is now bound in the Rmail summary to rmail-summary-goto-msg,
873 like `j'.
874
875 *** There is a new user option `rmail-digest-end-regexps' that
876 specifies the regular expressions to detect the line that ends a
877 digest message.
878
879 *** The new user option `rmail-automatic-folder-directives' specifies
880 in which folder to put messages automatically.
881
882 ** Changes to TeX mode
883
884 The default mode has been changed from `plain-tex-mode' to
885 `latex-mode'.
886
887 ** Changes to RefTeX mode
888
889 *** RefTeX has new support for index generation. Index entries can be
890 created with `C-c <', with completion available on index keys.
891 Pressing `C-c /' indexes the word at the cursor with a default
892 macro. `C-c >' compiles all index entries into an alphabetically
893 sorted *Index* buffer which looks like the final index. Entries
894 can be edited from that buffer.
895
896 *** Label and citation key selection now allow to select several
897 items and reference them together (use `m' to mark items, `a' or
898 `A' to use all marked entries).
899
900 *** reftex.el has been split into a number of smaller files to reduce
901 memory use when only a part of RefTeX is being used.
902
903 *** a new command `reftex-view-crossref-from-bibtex' (bound to `C-c &'
904 in BibTeX-mode) can be called in a BibTeX database buffer in order
905 to show locations in LaTeX documents where a particular entry has
906 been cited.
907
908 ** Emacs Lisp mode now allows multiple levels of outline headings.
909 The level of a heading is determined from the number of leading
910 semicolons in a heading line. Toplevel forms starting with a `('
911 in column 1 are always made leaves.
912
913 ** The M-x time-stamp command (most commonly used on write-file-hooks)
914 has the following new features:
915
916 *** The patterns for finding the time stamp and for updating a pattern
917 may match text spanning multiple lines. For example, some people like
918 to have the filename and date on separate lines. The new variable
919 time-stamp-inserts-lines controls the matching for multi-line patterns.
920
921 *** More than one time stamp can be updated in the same file. This
922 feature is useful if you need separate time stamps in a program source
923 file to both include in formatted documentation and insert in the
924 compiled binary. The same time-stamp will be written at each matching
925 pattern. The variable time-stamp-count enables this new feature; it
926 defaults to 1.
927
928 ** Partial Completion mode now completes environment variables in
929 file names.
930
931 +++
932 ** Tooltips.
933
934 Tooltips are small X windows displaying a help string at the current
935 mouse position. To use them, use the Lisp package `tooltip' which you
936 can access via the user option `tooltip-mode'.
937
938 Tooltips also provides support for GUD debugging. If activated,
939 variable values can be displayed in tooltips by pointing at them with
940 the mouse in source buffers. You can customize various aspects of the
941 tooltip display in the group `tooltip'.
942
943 +++
944 ** Customize changes
945
946 *** Customize now supports comments about customized items. Use the
947 `State' menu to add comments. Note that customization comments will
948 cause the customizations to fail in earlier versions of Emacs.
949
950 *** The new option `custom-buffer-done-function' says whether to kill
951 Custom buffers when you've done with them or just bury them (the
952 default).
953
954 *** The keyword :set-after in defcustom allows to specify dependencies
955 between custom options. Example:
956
957 (defcustom default-input-method nil
958 "*Default input method for multilingual text (a string).
959 This is the input method activated automatically by the command
960 `toggle-input-method' (\\[toggle-input-method])."
961 :group 'mule
962 :type '(choice (const nil) string)
963 :set-after '(current-language-environment))
964
965 This specifies that default-input-method should be set after
966 current-language-environment even if default-input-method appears
967 first in a custom-set-variables statement.
968
969 ** New features in evaluation commands
970
971 *** The commands to evaluate Lisp expressions, such as C-M-x in Lisp
972 modes, C-j in Lisp Interaction mode, and M-:, now bind the variables
973 print-level, print-length, and debug-on-error based on the
974 customizable variables eval-expression-print-level,
975 eval-expression-print-length, and eval-expression-debug-on-error.
976
977 *** The function `eval-defun' (M-C-x) now loads Edebug and instruments
978 code when called with a prefix argument.
979
980 ** Ispell changes
981
982 +++
983 *** The command `ispell' now spell-checks a region if
984 transient-mark-mode is on, and the mark is active. Otherwise it
985 spell-checks the current buffer.
986
987 +++
988 *** Support for synchronous subprocesses - DOS/Windoze - has been
989 added.
990
991 *** An "alignment error" bug was fixed when a manual spelling
992 correction is made and re-checked.
993
994 *** An Italian and a Portuguese dictionary definition has been added.
995
996 *** Region skipping performance has been vastly improved in some
997 cases.
998
999 *** Spell checking HTML buffers has been improved and isn't so strict
1000 on syntax errors.
1001
1002 *** The buffer-local words are now always placed on a new line at the
1003 end of the buffer.
1004
1005 ** Dired changes
1006
1007 *** New variable `dired-recursive-deletes' determines if the delete
1008 command will delete non-empty directories recursively. The default
1009 is, delete only empty directories.
1010
1011 *** New variable `dired-recursive-copies' determines if the copy
1012 command will copy directories recursively. The default is, do not
1013 copy directories recursively.
1014
1015 *** In command `dired-do-shell-command' (usually bound to `!') a `?'
1016 in the shell command has a special meaning similar to `*', but with
1017 the difference that the command will be run on each file individually.
1018
1019 *** The new command `dired-find-alternate-file' (usually bound to `a')
1020 replaces the Dired buffer with the buffer for an alternate file or
1021 directory.
1022
1023 *** The new command `dired-show-file-type' (usually bound to `w') shows
1024 a message in the echo area describing what type of file the point is on.
1025 This command invokes the external program `file' do its work, and so
1026 will only work on systems with that program, and will be only as
1027 accurate or inaccurate as it is.
1028
1029 *** Dired now properly handles undo changes of adding/removing `-R'
1030 from ls switches.
1031
1032 ** The variable mail-specify-envelope-from controls whether to
1033 use the -f option when sending mail.
1034
1035 ** CC mode changes.
1036
1037 Note: This release contains changes that might not be compatible with
1038 current user setups (although it's believed that these
1039 incompatibilities will only show in very uncommon circumstances).
1040 However, since the impact is uncertain, these changes may be rolled
1041 back depending on user feedback. Therefore there's no forward
1042 compatibility guarantee wrt the new features introduced in this
1043 release.
1044
1045 *** c-style-variables-are-local-p now defaults to t.
1046 This is an incompatible change that has been made to make the behavior
1047 of the style system wrt global variable settings less confusing for
1048 non-advanced users. If you know what this variable does you might
1049 want to set it to nil in your .emacs, otherwise you probably don't
1050 have to bother.
1051
1052 Defaulting c-style-variables-are-local-p to t avoids the confusing
1053 situation that occurs when a user sets some style variables globally
1054 and edits both a Java and a non-Java file in the same Emacs session.
1055 If the style variables aren't buffer local in this case, loading of
1056 the second file will cause the default style (either "gnu" or "java"
1057 by default) to override the global settings made by the user.
1058
1059 *** New initialization procedure for the style system.
1060 When the initial style for a buffer is determined by CC Mode (from the
1061 variable c-default-style), the global values of style variables now
1062 take precedence over the values specified by the chosen style. This
1063 is different than the old behavior: previously, the style-specific
1064 settings would override the global settings. This change makes it
1065 possible to do simple configuration in the intuitive way with
1066 Customize or with setq lines in one's .emacs file.
1067
1068 By default, the global value of every style variable is the new
1069 special symbol set-from-style, which causes the value to be taken from
1070 the style system. This means that in effect, only an explicit setting
1071 of a style variable will cause the "overriding" behavior described
1072 above.
1073
1074 Also note that global settings override style-specific settings *only*
1075 when the initial style of a buffer is chosen by a CC Mode major mode
1076 function. When a style is chosen in other ways --- for example, by a
1077 call like (c-set-style "gnu") in a hook, or via M-x c-set-style ---
1078 then the style-specific values take precedence over any global style
1079 values. In Lisp terms, global values override style-specific values
1080 only when the new second argument to c-set-style is non-nil; see the
1081 function documentation for more info.
1082
1083 The purpose of these changes is to make it easier for users,
1084 especially novice users, to do simple customizations with Customize or
1085 with setq in their .emacs files. On the other hand, the new system is
1086 intended to be compatible with advanced users' customizations as well,
1087 such as those that choose styles in hooks or whatnot. This new system
1088 is believed to be almost entirely compatible with current
1089 configurations, in spite of the changed precedence between style and
1090 global variable settings when a buffer's default style is set.
1091
1092 (Thanks to Eric Eide for clarifying this explanation a bit.)
1093
1094 **** c-offsets-alist is now a customizable variable.
1095 This became possible as a result of the new initialization behavior.
1096
1097 This variable is treated slightly differently from the other style
1098 variables; instead of using the symbol set-from-style, it will be
1099 completed with the syntactic symbols it doesn't already contain when
1100 the style is first initialized. This means it now defaults to the
1101 empty list to make all syntactic elements get their values from the
1102 style system.
1103
1104 **** Compatibility variable to restore the old behavior.
1105 In case your configuration doesn't work with this change, you can set
1106 c-old-style-variable-behavior to non-nil to get the old behavior back
1107 as far as possible.
1108
1109 *** Improvements to line breaking and text filling.
1110 CC Mode now handles this more intelligently and seamlessly wrt the
1111 surrounding code, especially inside comments. For details see the new
1112 chapter about this in the manual.
1113
1114 **** New variable to recognize comment line prefix decorations.
1115 The variable c-comment-prefix-regexp has been added to properly
1116 recognize the line prefix in both block and line comments. It's
1117 primarily used to initialize the various paragraph recognition and
1118 adaptive filling variables that the text handling functions uses.
1119
1120 **** New variable c-block-comment-prefix.
1121 This is a generalization of the now obsolete variable
1122 c-comment-continuation-stars to handle arbitrary strings.
1123
1124 **** CC Mode now uses adaptive fill mode.
1125 This to make it adapt better to the paragraph style inside comments.
1126
1127 It's also possible to use other adaptive filling packages inside CC
1128 Mode, notably Kyle E. Jones' Filladapt mode (http://wonderworks.com/).
1129 A new convenience function c-setup-filladapt sets up Filladapt for use
1130 inside CC Mode.
1131
1132 Note though that the 2.12 version of Filladapt lacks a feature that
1133 causes it to work suboptimally when c-comment-prefix-regexp can match
1134 the empty string (which it commonly does). A patch for that is
1135 available from the CC Mode web site (http://www.python.org/emacs/
1136 cc-mode/).
1137
1138 **** It's now possible to selectively turn off auto filling.
1139 The variable c-ignore-auto-fill is used to ignore auto fill mode in
1140 specific contexts, e.g. in preprocessor directives and in string
1141 literals.
1142
1143 **** New context sensitive line break function c-context-line-break.
1144 It works like newline-and-indent in normal code, and adapts the line
1145 prefix according to the comment style when used inside comments. If
1146 you're normally using newline-and-indent, you might want to switch to
1147 this function.
1148
1149 *** Fixes to IDL mode.
1150 It now does a better job in recognizing only the constructs relevant
1151 to IDL. E.g. it no longer matches "class" as the beginning of a
1152 struct block, but it does match the CORBA 2.3 "valuetype" keyword.
1153 Thanks to Eric Eide.
1154
1155 *** Improvements to the Whitesmith style.
1156 It now keeps the style consistently on all levels and both when
1157 opening braces hangs and when they don't.
1158
1159 **** New lineup function c-lineup-whitesmith-in-block.
1160
1161 *** New lineup functions c-lineup-template-args and c-indent-multi-line-block.
1162 See their docstrings for details. c-lineup-template-args does a
1163 better job of tracking the brackets used as parens in C++ templates,
1164 and is used by default to line up continued template arguments.
1165
1166 *** c-lineup-comment now preserves alignment with a comment on the
1167 previous line. It used to instead preserve comments that started in
1168 the column specified by comment-column.
1169
1170 *** c-lineup-C-comments handles "free form" text comments.
1171 In comments with a long delimiter line at the start, the indentation
1172 is kept unchanged for lines that start with an empty comment line
1173 prefix. This is intended for the type of large block comments that
1174 contain documentation with its own formatting. In these you normally
1175 don't want CC Mode to change the indentation.
1176
1177 *** The `c' syntactic symbol is now relative to the comment start
1178 instead of the previous line, to make integers usable as lineup
1179 arguments.
1180
1181 *** All lineup functions have gotten docstrings.
1182
1183 *** More preprocessor directive movement functions.
1184 c-down-conditional does the reverse of c-up-conditional.
1185 c-up-conditional-with-else and c-down-conditional-with-else are
1186 variants of these that also stops at "#else" lines (suggested by Don
1187 Provan).
1188
1189 *** Minor improvements to many movement functions in tricky situations.
1190
1191 ** Makefile mode changes
1192
1193 *** The mode now uses the abbrev table `makefile-mode-abbrev-table'.
1194
1195 *** Conditionals and include statements are now highlighted when
1196 Fontlock mode is active.
1197
1198 ** Isearch changes
1199
1200 *** Isearch now puts a call to `isearch-resume' in the command history,
1201 so that searches can be resumed.
1202
1203 *** In Isearch mode, M-C-s and M-C-r are now bound like C-s and C-r,
1204 respectively, i.e. you can repeat a regexp isearch with the same keys
1205 that started the search.
1206
1207 *** In Isearch mode, mouse-2 in the echo area now yanks the current
1208 selection into the search string rather than giving an error.
1209
1210 +++
1211 *** There is a new lazy highlighting feature in incremental search.
1212
1213 Lazy highlighting is switched on/off by customizing variable
1214 `isearch-lazy-highlight'. When active, all matches for the current
1215 search string are highlighted. The current match is highlighted as
1216 before using face `isearch' or `region'. All other matches are
1217 highlighted using face `isearch-lazy-highlight-face' which defaults to
1218 `secondary-selection'.
1219
1220 The extra highlighting makes it easier to anticipate where the cursor
1221 will end up each time you press C-s or C-r to repeat a pending search.
1222 Highlighting of these additional matches happens in a deferred fashion
1223 using "idle timers," so the cycles needed do not rob isearch of its
1224 usual snappy response.
1225
1226 If `isearch-lazy-highlight-cleanup' is set to t, highlights for
1227 matches are automatically cleared when you end the search. If it is
1228 set to nil, you can remove the highlights manually with `M-x
1229 isearch-lazy-highlight-cleanup'.
1230
1231 +++
1232 ** Changes in sort.el
1233
1234 The function sort-numeric-fields interprets numbers starting with `0'
1235 as octal and numbers starting with `0x' or `0X' as hexadecimal. The
1236 new user-option sort-numeric-base can be used to specify a default
1237 numeric base.
1238
1239 ** Changes to Ange-ftp
1240
1241 +++
1242 *** Ange-ftp allows you to specify of a port number in remote file
1243 names cleanly. It is appended to the host name, separated by a hash
1244 sign, e.g. `/foo@bar.org#666:mumble'. (This syntax comes from EFS.)
1245
1246 *** If the new user-option `ange-ftp-try-passive-mode' is set, passive
1247 ftp mode will be used if the ftp client supports that.
1248
1249 *** Ange-ftp handles the output of the w32-style clients which
1250 output ^M at the end of lines.
1251
1252 ** Shell script mode changes.
1253
1254 Shell script mode (sh-script) can now indent scripts for shells
1255 derived from sh and rc. The indentation style is customizeable, and
1256 sh-script can attempt to "learn" the current buffer's style.
1257
1258 ** Etags changes.
1259
1260 *** In DOS, etags looks for file.cgz if it cannot find file.c.
1261
1262 *** New option --ignore-case-regex is an alternative to --regex. It is now
1263 possible to bind a regexp to a language, by prepending the regexp with
1264 {lang}, where lang is one of the languages that `etags --help' prints out.
1265 This feature is useful especially for regex files, where each line contains
1266 a regular expression. The manual contains details.
1267
1268 *** In C and derived languages, etags creates tags for function
1269 declarations when given the --declarations option.
1270
1271 *** In C++, tags are created for "operator". The tags have the form
1272 "operator+", without spaces between the keyword and the operator.
1273
1274 *** New language Ada: tags are functions, procedures, packages, tasks, and
1275 types.
1276
1277 *** In Fortran, `procedure' is not tagged.
1278
1279 *** In Java, tags are created for "interface".
1280
1281 *** In Lisp, "(defstruct (foo", "(defun (operator" and similar constructs
1282 are now tagged.
1283
1284 *** In Perl, the --globals option tags global variables. my and local
1285 variables are tagged.
1286
1287 *** New language Python: def and class at the beginning of a line are tags.
1288
1289 *** .ss files are Scheme files, .pdb is Postscript with C syntax, .psw is
1290 for PSWrap.
1291
1292 +++
1293 ** Changes in etags.el
1294
1295 *** The new user-option tags-case-fold-search can be used to make
1296 tags operations case-sensitive or case-insensitive. The default
1297 is to use the same setting as case-fold-search.
1298
1299 *** You can display additional output with M-x tags-apropos by setting
1300 the new variable tags-apropos-additional-actions.
1301
1302 If non-nil, the variable's value should be a list of triples (TITLE
1303 FUNCTION TO-SEARCH). For each triple, M-x tags-apropos processes
1304 TO-SEARCH and lists tags from it. TO-SEARCH should be an alist,
1305 obarray, or symbol. If it is a symbol, the symbol's value is used.
1306
1307 TITLE is a string to use to label the list of tags from TO-SEARCH.
1308
1309 FUNCTION is a function to call when an entry is selected in the Tags
1310 List buffer. It is called with one argument, the selected symbol.
1311
1312 A useful example value for this variable might be something like:
1313
1314 '(("Emacs Lisp" Info-goto-emacs-command-node obarray)
1315 ("Common Lisp" common-lisp-hyperspec common-lisp-hyperspec-obarray)
1316 ("SCWM" scwm-documentation scwm-obarray))
1317
1318 *** The face tags-tag-face can be used to customize the appearance
1319 of tags in the output of M-x tags-apropos.
1320
1321 *** Setting tags-apropos-verbose to a non-nil value displays the
1322 names of tags files in the *Tags List* buffer.
1323
1324 +++
1325 ** Emacs now attempts to determine the initial language environment
1326 and preferred and locale coding systems systematically from the
1327 LC_ALL, LC_CTYPE, and LANG environment variables during startup.
1328
1329 +++
1330 ** New language environments `Polish', `Latin-8' and `Latin-9'.
1331 Latin-8 and Latin-9 correspond respectively to the ISO character sets
1332 8859-14 (Celtic) and 8859-15 (updated Latin-1, with the Euro sign).
1333 GNU Intlfonts doesn't support these yet; there are basic 8859-14 and
1334 8859-15 fonts at <URL:http://czyborra.com/charsets/> and recent X
1335 releases have 8859-15. There are new Latin-8 and Latin-9 prefix
1336 (only) and Polish slash input methods in Leim.
1337
1338 +++
1339 ** Fortran mode has a new command `fortran-strip-sequence-nos' to
1340 remove text past column 72. The syntax class of `\' in Fortran is now
1341 appropriate for C-style escape sequences in strings.
1342
1343 ** SGML mode's default `sgml-validate-command' is now `nsgmls'.
1344
1345 +++
1346 ** A new command `view-emacs-problems' (C-h P) displays the PROBLEMS file.
1347
1348 +++
1349 ** The Dabbrev package has a new user-option `dabbrev-ignored-regexps'
1350 containing a list of regular expressions. Buffers matching a regular
1351 expression from that list, are not checked.
1352
1353 ** Emacs can now figure out modification times of remote files.
1354 When you do C-x C-f /user@host:/path/file RET and edit the file,
1355 and someone else modifies the file, you will be prompted to revert
1356 the buffer, just like for the local files.
1357
1358 ** The buffer menu (C-x C-b) no longer lists the *Buffer List* buffer.
1359
1360 +++
1361 ** When invoked with a prefix argument, the command `list-abbrevs' now
1362 displays local abbrevs, only.
1363
1364 ** VC Changes
1365
1366 VC has been overhauled internally. It is now modular, making it
1367 easier to plug-in arbitrary version control backends. (See Lisp
1368 Changes for details on the new structure.) As a result, the mechanism
1369 to enable and disable support for particular version systems has
1370 changed: everything is now controlled by the new variable
1371 `vc-handled-backends'. Its value is a list of atoms that identify
1372 version systems; the default is '(RCS CVS SCCS). When finding a file,
1373 each of the backends in that list is tried in order to see whether the
1374 file is registered in that backend.
1375
1376 When registering a new file, VC first tries each of the listed
1377 backends to see if any of them considers itself "responsible" for the
1378 directory of the file (e.g. because a corresponding subdirectory for
1379 master files exists). If none of the backends is responsible, then
1380 the first backend in the list that could register the file is chosen.
1381 As a consequence, the variable `vc-default-back-end' is now obsolete.
1382
1383 The old variable `vc-master-templates' is also obsolete, although VC
1384 still supports it for backward compatibility. To define templates for
1385 RCS or SCCS, you should rather use the new variables
1386 vc-{rcs,sccs}-master-templates. (There is no such feature under CVS
1387 where it doesn't make sense.)
1388
1389 The variables `vc-ignore-vc-files' and `vc-handle-cvs' are also
1390 obsolete now, you must set `vc-handled-backends' to nil or exclude
1391 `CVS' from the list, respectively, to achieve their effect now.
1392
1393 *** General Changes
1394
1395 The variable `vc-checkout-carefully' is obsolete: the corresponding
1396 checks are always done now.
1397
1398 VC Dired buffers are now kept up-to-date during all version control
1399 operations.
1400
1401 *** Changes for CVS
1402
1403 There is a new user option, `vc-cvs-stay-local'. If it is `t' (the
1404 default), then VC avoids network queries for files registered in
1405 remote repositories. The state of such files is then only determined
1406 by heuristics and past information. `vc-cvs-stay-local' can also be a
1407 regexp to match against repository hostnames; only files from hosts
1408 that match it are treated locally. If the variable is nil, then VC
1409 queries the repository just as often as it does for local files.
1410
1411 If `vc-cvs-stay-local' is on, and there have been changes in the
1412 repository, VC notifies you about it when you actually try to commit.
1413 If you want to check for updates from the repository without trying to
1414 commit, you can either use C-u C-x v m to perform an update on the
1415 current file, or you can use C-x v r RET to get an update for an
1416 entire directory tree.
1417
1418 The new user option `vc-cvs-use-edit' indicates whether VC should call
1419 "cvs edit" to make files writeable; it defaults to `t'. (This option
1420 is only meaningful if the CVSREAD variable is set, or if files are
1421 "watched" by other developers.)
1422
1423 *** Lisp Changes in VC
1424
1425 VC has been restructured internally to make it modular. You can now
1426 add support for arbitrary version control backends by writing a
1427 library that provides a certain set of backend-specific functions, and
1428 then telling VC to use that library. For example, to add support for
1429 a version system named FOO, you write a library named vc-foo.el, which
1430 provides a number of functions vc-foo-... (see commentary at the end
1431 of vc.el for a detailed list of them). To make VC use that library,
1432 you need to put it somewhere into Emacs' load path and add the atom
1433 `FOO' to the list `vc-handled-backends'.
1434
1435 ** New modes and packages
1436
1437 +++
1438 *** The new package timeclock.el is a mode is for keeping track of time
1439 intervals. You can use it for whatever purpose you like, but the
1440 typical scenario is to keep track of how much time you spend working
1441 on certain projects.
1442
1443 +++
1444 *** The new package hi-lock.el, text matching interactively entered
1445 regexp's can be highlighted. For example,
1446
1447 M-x highlight-regexp RET clearly RET RET
1448
1449 will highlight all occurrences of `clearly' using a yellow background
1450 face. New occurrences of `clearly' will be highlighted as they are
1451 typed. `M-x unhighlight-regexp RET' will remove the highlighting.
1452 Any existing face can be used for highlighting and a set of
1453 appropriate faces is provided. The regexps can be written into the
1454 current buffer in a form that will be recognized the next time the
1455 corresponding file is read.
1456
1457 +++
1458 *** The new package zone.el plays games with Emacs' display when
1459 Emacs is idle.
1460
1461 *** The new package xml.el provides a simple but generic XML
1462 parser. It doesn't parse the DTDs however.
1463
1464 *** The comment operations are now provided by the newcomment.el
1465 package which allows different styles of comment-region and should
1466 be more robust while offering the same functionality.
1467
1468 +++
1469 *** The Ebrowse package implements a C++ class browser and tags
1470 facilities tailored for use with C++. It is documented in a
1471 separate Texinfo file.
1472
1473 +++
1474 *** The PCL-CVS package available by either running M-x cvs-examine or
1475 by visiting a CVS administrative directory (with a prefix argument)
1476 provides an alternative interface to VC-dired for CVS. It comes with
1477 `log-view-mode' to view RCS and SCCS logs and `log-edit-mode' used to
1478 enter checkin log messages.
1479
1480 +++
1481 *** The new package called `woman' allows to browse Unix man pages
1482 without invoking external programs.
1483
1484 The command `M-x woman' formats manual pages entirely in Emacs Lisp
1485 and then displays them, like `M-x manual-entry' does. Unlike
1486 `manual-entry', `woman' does not invoke any external programs, so it
1487 is useful on systems such as MS-DOS/MS-Windows where the `man' and
1488 Groff or `troff' commands are not readily available.
1489
1490 The command `M-x woman-find-file' asks for the file name of a man
1491 page, then formats and displays it like `M-x woman' does.
1492
1493 +++
1494 *** The new command M-x re-builder offers a convenient interface for
1495 authoring regular expressions with immediate visual feedback.
1496
1497 The buffer from which the command was called becomes the target for
1498 the regexp editor popping up in a separate window. Matching text in
1499 the target buffer is immediately color marked during the editing.
1500 Each sub-expression of the regexp will show up in a different face so
1501 even complex regexps can be edited and verified on target data in a
1502 single step.
1503
1504 On displays not supporting faces the matches instead blink like
1505 matching parens to make them stand out. On such a setup you will
1506 probably also want to use the sub-expression mode when the regexp
1507 contains such to get feedback about their respective limits.
1508
1509 +++
1510 *** glasses-mode is a minor mode that makes
1511 unreadableIdentifiersLikeThis readable. It works as glasses, without
1512 actually modifying content of a buffer.
1513
1514 *** The package ebnf2ps translates an EBNF to a syntactic chart in
1515 PostScript.
1516
1517 Currently accepts ad-hoc EBNF, ISO EBNF and Bison/Yacc.
1518
1519 The ad-hoc default EBNF syntax has the following elements:
1520
1521 ; comment (until end of line)
1522 A non-terminal
1523 "C" terminal
1524 ?C? special
1525 $A default non-terminal
1526 $"C" default terminal
1527 $?C? default special
1528 A = B. production (A is the header and B the body)
1529 C D sequence (C occurs before D)
1530 C | D alternative (C or D occurs)
1531 A - B exception (A excluding B, B without any non-terminal)
1532 n * A repetition (A repeats n (integer) times)
1533 (C) group (expression C is grouped together)
1534 [C] optional (C may or not occurs)
1535 C+ one or more occurrences of C
1536 {C}+ one or more occurrences of C
1537 {C}* zero or more occurrences of C
1538 {C} zero or more occurrences of C
1539 C / D equivalent to: C {D C}*
1540 {C || D}+ equivalent to: C {D C}*
1541 {C || D}* equivalent to: [C {D C}*]
1542 {C || D} equivalent to: [C {D C}*]
1543
1544 Please, see ebnf2ps documentation for EBNF syntax and how to use it.
1545
1546 *** The package align.el will align columns within a region, using M-x
1547 align. Its mode-specific rules, based on regular expressions,
1548 determine where the columns should be split. In C and C++, for
1549 example, it will align variable names in declaration lists, or the
1550 equal signs of assignments.
1551
1552 +++
1553 *** `paragraph-indent-minor-mode' is a new minor mode supporting
1554 paragraphs in the same style as `paragraph-indent-text-mode'.
1555
1556 +++
1557 *** bs.el is a new package for buffer selection similar to
1558 list-buffers or electric-buffer-list. Use M-x bs-show to display a
1559 buffer menu with this package. You can use M-x bs-customize to
1560 customize the package.
1561
1562 *** find-lisp.el is a package emulating the Unix find command in Lisp.
1563
1564 *** calculator.el is a small calculator package that is intended to
1565 replace desktop calculators such as xcalc and calc.exe. Actually, it
1566 is not too small - it has more features than most desktop calculators,
1567 and can be customized easily to get many more functions. It should
1568 not be confused with "calc" which is a much bigger mathematical tool
1569 which answers different needs.
1570
1571 +++
1572 *** The minor modes cwarn-mode and global-cwarn-mode highlights
1573 suspicious C and C++ constructions. Currently, assignments inside
1574 expressions, semicolon following `if', `for' and `while' (except, of
1575 course, after a `do .. while' statement), and C++ functions with
1576 reference parameters are recognized. The modes require font-lock mode
1577 to be enabled.
1578
1579 +++
1580 *** smerge-mode.el provides `smerge-mode', a simple minor-mode for files
1581 containing diff3-style conflict markers, such as generated by RCS.
1582
1583 +++
1584 *** 5x5.el is a simple puzzle game.
1585
1586 +++
1587 *** hl-line.el provides a minor mode to highlight the current line.
1588
1589 *** ansi-color.el translates ANSI terminal escapes into text-properties.
1590
1591 *** delphi.el provides a major mode for editing the Delphi (Object
1592 Pascal) language.
1593
1594 +++
1595 *** quickurl.el provides a simple method of inserting a URL based on
1596 the text at point.
1597
1598 *** sql.el provides an interface to SQL data bases.
1599
1600 +++
1601 *** fortune.el uses the fortune program to create mail/news signatures.
1602
1603 *** whitespace.el ???
1604
1605 *** PostScript mode (ps-mode) is a new major mode for editing PostScript
1606 files. It offers: interaction with a PostScript interpreter, including
1607 (very basic) error handling; fontification, easily customizable for
1608 interpreter messages; auto-indentation; insertion of EPSF templates and
1609 often used code snippets; viewing of BoundingBox; commenting out /
1610 uncommenting regions; conversion of 8bit characters to PostScript octal
1611 codes. All functionality is accessible through a menu.
1612
1613 *** delim-col helps to prettify columns in a text region or rectangle.
1614
1615 Here is an example of columns:
1616
1617 horse apple bus
1618 dog pineapple car EXTRA
1619 porcupine strawberry airplane
1620
1621 Doing the following settings:
1622
1623 (setq delimit-columns-str-before "[ ")
1624 (setq delimit-columns-str-after " ]")
1625 (setq delimit-columns-str-separator ", ")
1626 (setq delimit-columns-separator "\t")
1627
1628
1629 Selecting the lines above and typing:
1630
1631 M-x delimit-columns-region
1632
1633 It results:
1634
1635 [ horse , apple , bus , ]
1636 [ dog , pineapple , car , EXTRA ]
1637 [ porcupine, strawberry, airplane, ]
1638
1639 delim-col has the following options:
1640
1641 delimit-columns-str-before Specify a string to be inserted
1642 before all columns.
1643
1644 delimit-columns-str-separator Specify a string to be inserted
1645 between each column.
1646
1647 delimit-columns-str-after Specify a string to be inserted
1648 after all columns.
1649
1650 delimit-columns-separator Specify a regexp which separates
1651 each column.
1652
1653 delim-col has the following commands:
1654
1655 delimit-columns-region Prettify all columns in a text region.
1656 delimit-columns-rectangle Prettify all columns in a text rectangle.
1657
1658 +++
1659 *** The package recentf.el maintains a menu for visiting files that
1660 were operated on recently.
1661
1662 M-x recentf-mode RET toggles recentf mode.
1663
1664 M-x customize-variable RET recentf-mode RET can be used to enable
1665 recentf at Emacs startup.
1666
1667 M-x customize-variable RET recentf-menu-filter RET to specify a menu
1668 filter function to change the menu appearance. For example, the recent
1669 file list can be displayed:
1670
1671 - organized by major modes, directories or user defined rules.
1672 - sorted by file pathes, file names, ascending or descending.
1673 - showing pathes relative to the current default-directory
1674
1675 The `recentf-filter-changer' menu filter function allows to
1676 dynamically change the menu appearance.
1677
1678 *** elide-head.el provides a mechanism for eliding boilerplate header
1679 text.
1680
1681 +++
1682 *** footnote.el provides `footnote-mode', a minor mode supporting use
1683 of footnotes. It is intended for use with Message mode, but isn't
1684 specific to Message mode.
1685
1686 +++
1687 *** diff-mode.el provides `diff-mode', a major mode for
1688 viewing/editing context diffs (patches). It is selected for files
1689 with extension `.diff', `.diffs', `.patch' and `.rej'.
1690
1691 +++
1692 *** EUDC, the Emacs Unified Directory Client, provides a common user
1693 interface to access directory servers using different directory
1694 protocols. It has a separate manual.
1695
1696 *** autoconf.el provides a major mode for editing configure.in files
1697 for Autoconf, selected automatically.
1698
1699 +++
1700 *** windmove.el provides moving between windows.
1701
1702 *** crm.el provides a facility to read multiple strings from the
1703 minibuffer with completion.
1704
1705 *** todo-mode.el provides management of TODO lists and integration
1706 with the diary features.
1707
1708 *** autoarg.el provides a feature reported from Twenex Emacs whereby
1709 numeric keys supply prefix args rather than self inserting.
1710
1711 *** The function `turn-off-auto-fill' unconditionally turns off Auto
1712 Fill mode.
1713
1714 ** Withdrawn packages
1715
1716 *** mldrag.el has been removed. mouse.el provides the same
1717 functionality with aliases for the mldrag functions.
1718
1719 *** eval-reg.el has been obsoleted by changes to edebug.el and removed.
1720
1721 *** ph.el has been obsoleted by EUDC and removed.
1722
1723 \f
1724 * Lisp changes made after edition 2.6 of the Emacs Lisp Manual,
1725 (Display-related features are described in a page of their own below.)
1726
1727 ** In image specifications, `:heuristic-mask' has been replaced
1728 with the more general `:mask' property.
1729
1730 ** Image specifications accept more `:algorithm's.
1731
1732 ** A `?' can be used in a symbol name without escaping it with a
1733 backslash.
1734
1735 +++
1736 ** Reading from the mini-buffer now reads from standard input if Emacs
1737 is running in batch mode. For example,
1738
1739 (message "%s" (read t))
1740
1741 will read a Lisp expression from standard input and print the result
1742 to standard output.
1743
1744 +++
1745 ** The argument of `down-list', `backward-up-list', `up-list',
1746 `kill-sexp', `backward-kill-sexp' and `mark-sexp' is now optional.
1747
1748 ** If `display-buffer-reuse-frames' is set, function `display-buffer'
1749 will raise frames displaying a buffer, instead of creating a new
1750 frame or window.
1751
1752 +++
1753 ** Two new functions for removing elements from lists/sequences
1754 were added
1755
1756 - Function: remove ELT SEQ
1757
1758 Return a copy of SEQ with all occurences of ELT removed. SEQ must be
1759 a list, vector, or string. The comparison is done with `equal'.
1760
1761 - Function: remq ELT LIST
1762
1763 Return a copy of LIST with all occurences of ELT removed. The
1764 comparison is done with `eq'.
1765
1766 ** The function `delete' now also works with vectors and strings.
1767
1768 ** The meaning of the `:weakness WEAK' argument of make-hash-table
1769 has been changed.
1770
1771 +++
1772 ** Function `aset' stores any multibyte character in any string
1773 without signaling "Attempt to change char length of a string". It may
1774 convert a unibyte string to multibyte if necessary.
1775
1776 ** The value of the `help-echo' text property is called as a function
1777 or evaluated, if it is not a string already, to obtain a help string.
1778
1779 ** Function `make-obsolete' now has an optional arg to say when the
1780 function was declared obsolete.
1781
1782 ** Function `plist-member' is renamed from `widget-plist-member' (which is
1783 retained as an alias).
1784
1785 ** Easy-menu's :filter now works as in XEmacs.
1786 It takes the unconverted (i.e. XEmacs) form of the menu and the result
1787 is automatically converted to Emacs' form.
1788
1789 ** The new function `window-list' has been defined
1790
1791 - Function: window-list &optional WINDOW MINIBUF ALL-FRAMES
1792
1793 Return a list of windows in canonical order. The parameters WINDOW,
1794 MINIBUF and ALL-FRAMES are defined like for `next-window'.
1795
1796 ** There's a new function `some-window' defined as follows
1797
1798 - Function: some-window PREDICATE &optional MINIBUF ALL-FRAMES DEFAULT
1799
1800 Return a window satisfying PREDICATE.
1801
1802 This function cycles through all visible windows using `walk-windows',
1803 calling PREDICATE on each one. PREDICATE is called with a window as
1804 argument. The first window for which PREDICATE returns a non-nil
1805 value is returned. If no window satisfies PREDICATE, DEFAULT is
1806 returned.
1807
1808 Optional second arg MINIBUF t means count the minibuffer window even
1809 if not active. MINIBUF nil or omitted means count the minibuffer iff
1810 it is active. MINIBUF neither t nor nil means not to count the
1811 minibuffer even if it is active.
1812
1813 Several frames may share a single minibuffer; if the minibuffer
1814 counts, all windows on all frames that share that minibuffer count
1815 too. Therefore, if you are using a separate minibuffer frame
1816 and the minibuffer is active and MINIBUF says it counts,
1817 `walk-windows' includes the windows in the frame from which you
1818 entered the minibuffer, as well as the minibuffer window.
1819
1820 ALL-FRAMES is the optional third argument.
1821 ALL-FRAMES nil or omitted means cycle within the frames as specified above.
1822 ALL-FRAMES = `visible' means include windows on all visible frames.
1823 ALL-FRAMES = 0 means include windows on all visible and iconified frames.
1824 ALL-FRAMES = t means include windows on all frames including invisible frames.
1825 If ALL-FRAMES is a frame, it means include windows on that frame.
1826 Anything else means restrict to the selected frame.
1827
1828 ** The function `single-key-description' now encloses function key and
1829 event names in angle brackets. When called with a second optional
1830 argument non-nil, angle brackets won't be printed.
1831
1832 ** If the variable `message-truncate-lines' is bound to t around a
1833 call to `message', the echo area will not be resized to display that
1834 message; it will be truncated instead, as it was done in 20.x.
1835 Default value is nil.
1836
1837 ** The user option `line-number-display-limit' can now be set to nil,
1838 meaning no limit.
1839
1840 ** `select-safe-coding-system' now also checks the most preferred
1841 coding-system if buffer-file-coding-system is `undecided' and
1842 DEFAULT-CODING-SYSTEM is not specified,
1843
1844 ** The function `subr-arity' provides information on the argument list
1845 of a primitive.
1846
1847 ** The text property `keymap' specifies a key map which overrides the
1848 buffer's local map and the map specified by the `local-map' property.
1849 This is probably what most current uses of `local-map' want, rather
1850 than replacing the local map.
1851
1852 ** The obsolete variables before-change-function and
1853 after-change-function are no longer acted upon and have been removed.
1854
1855 ** The function `apropos-mode' runs the hook `apropos-mode-hook'.
1856
1857 +++
1858 ** `concat' no longer accepts individual integer arguments, as
1859 promised long ago.
1860
1861 ** The new function `float-time' returns the current time as a float.
1862 \f
1863 * Lisp changes in Emacs 21.1 (see following page for display-related features)
1864
1865 Note that +++ before an item means the Lisp manual has been updated.
1866 --- means that I have decided it does not need to be in the Lisp manual.
1867 When you add a new item, please add it without either +++ or ---
1868 so I will know I still need to look at it -- rms.
1869
1870 *** The special form `save-restriction' now works correctly even if the
1871 buffer is widened inside the save-restriction and changes made outside
1872 the original restriction. Previously, doing this would cause the saved
1873 restriction to be restored incorrectly.
1874
1875 *** The functions `find-charset-region' and `find-charset-string' include
1876 `eight-bit-control' and/or `eight-bit-graphic' in the returned list
1877 when it finds 8-bit characters. Previously, it included `ascii' in a
1878 multibyte buffer and `unknown' in a unibyte buffer.
1879
1880 *** The functions `set-buffer-modified', `string-as-multibyte' and
1881 `string-as-unibyte' change the byte sequence of a buffer if it
1882 contains a character from the `eight-bit-control' character set.
1883
1884 *** The handling of multibyte sequences in a multibyte buffer is
1885 changed. Previously, a byte sequence matching the pattern
1886 [\200-\237][\240-\377]+ was interpreted as a single character
1887 regardless of the length of the trailing bytes [\240-\377]+. Thus, if
1888 the sequence was longer than what the leading byte indicated, the
1889 extra trailing bytes were ignored by Lisp functions. Now such extra
1890 bytes are independent 8-bit characters belonging to the charset
1891 eight-bit-graphic.
1892
1893 ** Fontsets are now implemented using char-tables.
1894
1895 A fontset can now be specified for for each independent character, for
1896 a group of characters or for a character set rather than just for a
1897 character set as previously.
1898
1899 *** The arguments of the function `set-fontset-font' are changed.
1900 They are NAME, CHARACTER, FONTNAME, and optional FRAME. The function
1901 modifies fontset NAME to use FONTNAME for CHARACTER.
1902
1903 CHARACTER may be a cons (FROM . TO), where FROM and TO are non-generic
1904 characters. In that case FONTNAME is used for all characters in the
1905 range FROM and TO (inclusive). CHARACTER may be a charset. In that
1906 case FONTNAME is used for all character in the charset.
1907
1908 FONTNAME may be a cons (FAMILY . REGISTRY), where FAMILY is the family
1909 name of a font and REGSITRY is a registry name of a font.
1910
1911 *** Variable x-charset-registry has been deleted. The default charset
1912 registries of character sets are set in the default fontset
1913 "fontset-default".
1914
1915 *** The function `create-fontset-from-fontset-spec' ignores the second
1916 argument STYLE-VARIANT. It never creates style-variant fontsets.
1917
1918 ** The method of composing characters is changed. Now character
1919 composition is done by a special text property `composition' in
1920 buffers and strings.
1921
1922 *** Charset composition is deleted. Emacs never creates a `composite
1923 character' which is an independent character with a unique character
1924 code. Thus the following functions handling `composite characters'
1925 have been deleted: composite-char-component,
1926 composite-char-component-count, composite-char-composition-rule,
1927 composite-char-composition-rule and decompose-composite-char delete.
1928 The variables leading-code-composition and min-composite-char have
1929 also been deleted.
1930
1931 *** Three more glyph reference points are added. They can be used to
1932 specify a composition rule. See the documentation of the variable
1933 `reference-point-alist' for more detail.
1934
1935 *** The function `compose-region' takes new arguments COMPONENTS and
1936 MODIFICATION-FUNC. With COMPONENTS, you can specify not only a
1937 composition rule but also characters to be composed. Such characters
1938 may differ between buffer and string text.
1939
1940 *** The function `compose-string' takes new arguments START, END,
1941 COMPONENTS, and MODIFICATION-FUNC.
1942
1943 *** The function `compose-string' puts text property `composition'
1944 directly on the argument STRING instead of returning a new string.
1945 Likewise, the function `decompose-string' just removes text property
1946 `composition' from STRING.
1947
1948 *** The new function `find-composition' returns information about
1949 a composition at a specified position in a buffer or a string.
1950
1951 *** The function `decompose-composite-char' is now labeled as
1952 obsolete.
1953
1954 ** The new character set `mule-unicode-0100-24ff' is introduced for
1955 Unicode characters of the range U+0100..U+24FF. Currently, this
1956 character set is not used.
1957
1958 ** The new character sets `japanese-jisx0213-1' and
1959 `japanese-jisx0213-2' are introduced for the new Japanese standard JIS
1960 X 0213 Plane 1 and Plane 2.
1961
1962 +++
1963 ** The new character sets `eight-bit-control' and `eight-bit-graphic'
1964 are introduced for 8-bit characters in the ranges 0x80..0x9F and
1965 0xA0..0xFF respectively.
1966
1967 +++
1968 ** If the APPEND argument of `write-region' is an integer, it seeks to
1969 that offset in the file before writing.
1970
1971 ** The function `add-minor-mode' has been added for convenience and
1972 compatibility with XEmacs (and is used internally by define-minor-mode).
1973
1974 ** The function `shell-command' now sets the default directory of the
1975 `*Shell Command Output*' buffer to the default directory of the buffer
1976 from which the command was issued.
1977
1978 ** The functions `query-replace', `query-replace-regexp',
1979 `query-replace-regexp-eval' `map-query-replace-regexp',
1980 `replace-string', `replace-regexp', and `perform-replace' take two
1981 additional optional arguments START and END that specify the region to
1982 operate on.
1983
1984 ** The new function `count-screen-lines' is a more flexible alternative
1985 to `window-buffer-height'.
1986
1987 - Function: count-screen-lines &optional BEG END COUNT-FINAL-NEWLINE WINDOW
1988
1989 Return the number of screen lines in the region between BEG and END.
1990 The number of screen lines may be different from the number of actual
1991 lines, due to line breaking, display table, etc.
1992
1993 Optional arguments BEG and END default to `point-min' and `point-max'
1994 respectively.
1995
1996 If region ends with a newline, ignore it unless optinal third argument
1997 COUNT-FINAL-NEWLINE is non-nil.
1998
1999 The optional fourth argument WINDOW specifies the window used for
2000 obtaining parameters such as width, horizontal scrolling, and so
2001 on. The default is to use the selected window's parameters.
2002
2003 Like `vertical-motion', `count-screen-lines' always uses the current
2004 buffer, regardless of which buffer is displayed in WINDOW. This makes
2005 possible to use `count-screen-lines' in any buffer, whether or not it
2006 is currently displayed in some window.
2007
2008 ** The new function `mapc' is like `mapcar' but doesn't collect the
2009 argument function's results.
2010
2011 ** The functions base64-decode-region and base64-decode-string now
2012 signal an error instead of returning nil if decoding fails.
2013
2014 ** The function sendmail-user-agent-compose now recognizes a `body'
2015 header in the list of headers passed to it.
2016
2017 ** The new function member-ignore-case works like `member', but
2018 ignores differences in case and text representation.
2019
2020 ** The buffer-local variable cursor-type can be used to specify the
2021 cursor to use in windows displaying a buffer. Values are interpreted
2022 as follows:
2023
2024 t use the cursor specified for the frame (default)
2025 nil don't display a cursor
2026 `bar' display a bar cursor with default width
2027 (bar . WIDTH) display a bar cursor with width WIDTH
2028 others display a box cursor.
2029
2030 ** The variable open-paren-in-column-0-is-defun-start controls whether
2031 an open parenthesis in column 0 is considered to be the start of a
2032 defun. If set, the default, it is considered a defun start. If not
2033 set, an open parenthesis in column 0 has no special meaning.
2034
2035 ** The new function `string-to-syntax' can be used to translate syntax
2036 specifications in string form as accepted by `modify-syntax-entry' to
2037 the cons-cell form that is used for the values of the `syntax-table'
2038 text property, and in `font-lock-syntactic-keywords'.
2039
2040 Example:
2041
2042 (string-to-syntax "()")
2043 => (4 . 41)
2044
2045 ** Emacs' reader supports CL read syntax for integers in bases
2046 other than 10.
2047
2048 *** `#BINTEGER' or `#bINTEGER' reads INTEGER in binary (radix 2).
2049 INTEGER optionally contains a sign.
2050
2051 #b1111
2052 => 15
2053 #b-1111
2054 => -15
2055
2056 *** `#OINTEGER' or `#oINTEGER' reads INTEGER in octal (radix 8).
2057
2058 #o666
2059 => 438
2060
2061 *** `#XINTEGER' or `#xINTEGER' reads INTEGER in hexadecimal (radix 16).
2062
2063 #xbeef
2064 => 48815
2065
2066 *** `#RADIXrINTEGER' reads INTEGER in radix RADIX, 2 <= RADIX <= 36.
2067
2068 #2R-111
2069 => -7
2070 #25rah
2071 => 267
2072
2073 ** The function `documentation-property' now evaluates the value of
2074 the given property to obtain a string if it doesn't refer to etc/DOC
2075 and isn't a string.
2076
2077 ** If called for a symbol, the function `documentation' now looks for
2078 a `function-documentation' property of that symbol. If it has a non-nil
2079 value, the documentation is taken from that value. If the value is
2080 not a string, it is evaluated to obtain a string.
2081
2082 +++
2083 ** The last argument of `define-key-after' defaults to t for convenience.
2084
2085 ** The new function `replace-regexp-in-string' replaces all matches
2086 for a regexp in a string.
2087
2088 ** `mouse-position' now runs the abnormal hook
2089 `mouse-position-function'.
2090
2091 ** The function string-to-number now returns a float for numbers
2092 that don't fit into a Lisp integer.
2093
2094 ** The variable keyword-symbols-constants-flag has been removed.
2095 Keywords are now always considered constants.
2096
2097 +++
2098 ** The new function `delete-and-extract-region' deletes text and
2099 returns it.
2100
2101 ** The function `clear-this-command-keys' now also clears the vector
2102 returned by function `recent-keys'.
2103
2104 +++
2105 ** Variables `beginning-of-defun-function' and `end-of-defun-function'
2106 can be used to define handlers for the functions that find defuns.
2107 Major modes can define these locally instead of rebinding M-C-a
2108 etc. if the normal conventions for defuns are not appropriate for the
2109 mode.
2110
2111 +++
2112 ** easy-mmode-define-minor-mode now takes an additional BODY argument
2113 and is renamed `define-minor-mode'.
2114
2115 +++
2116 ** If an abbrev has a hook function which is a symbol, and that symbol
2117 has a non-nil `no-self-insert' property, the return value of the hook
2118 function specifies whether an expansion has been done or not. If it
2119 returns nil, abbrev-expand also returns nil, meaning "no expansion has
2120 been performed."
2121
2122 When abbrev expansion is done by typing a self-inserting character,
2123 and the abbrev has a hook with the `no-self-insert' property, and the
2124 hook function returns non-nil meaning expansion has been done,
2125 then the self-inserting character is not inserted.
2126
2127 +++
2128 ** The function `intern-soft' now accepts a symbol as first argument.
2129 In this case, that exact symbol is looked up in the specified obarray,
2130 and the function's value is nil if it is not found.
2131
2132 +++
2133 ** The new macro `with-syntax-table' can be used to evaluate forms
2134 with the syntax table of the current buffer temporarily set to a
2135 specified table.
2136
2137 (with-syntax-table TABLE &rest BODY)
2138
2139 Evaluate BODY with syntax table of current buffer set to a copy of
2140 TABLE. The current syntax table is saved, BODY is evaluated, and the
2141 saved table is restored, even in case of an abnormal exit. Value is
2142 what BODY returns.
2143
2144 +++
2145 ** Regular expressions now support intervals \{n,m\} as well as
2146 Perl's shy-groups \(?:...\) and non-greedy *? +? and ?? operators.
2147
2148 +++
2149 ** The optional argument BUFFER of function file-local-copy has been
2150 removed since it wasn't used by anything.
2151
2152 +++
2153 ** The file name argument of function `file-locked-p' is now required
2154 instead of being optional.
2155
2156 +++
2157 ** The new built-in error `text-read-only' is signaled when trying to
2158 modify read-only text.
2159
2160 +++
2161 ** New functions and variables for locales.
2162
2163 The new variable `locale-coding-system' specifies how to encode and
2164 decode strings passed to low-level message functions like strerror and
2165 time functions like strftime. The new variables
2166 `system-messages-locale' and `system-time-locale' give the system
2167 locales to be used when invoking these two types of functions.
2168
2169 The new function `set-locale-environment' sets the language
2170 environment, preferred coding system, and locale coding system from
2171 the system locale as specified by the LC_ALL, LC_CTYPE, and LANG
2172 environment variables. Normally, it is invoked during startup and need
2173 not be invoked thereafter. It uses the new variables
2174 `locale-language-names', `locale-charset-language-names', and
2175 `locale-preferred-coding-systems' to make its decisions.
2176
2177 +++
2178 ** syntax tables now understand nested comments.
2179 To declare a comment syntax as allowing nesting, just add an `n'
2180 modifier to either of the characters of the comment end and the comment
2181 start sequences.
2182
2183 +++
2184 ** The function `pixmap-spec-p' has been renamed `bitmap-spec-p'
2185 because `bitmap' is more in line with the usual X terminology.
2186
2187 +++
2188 ** New function `propertize'
2189
2190 The new function `propertize' can be used to conveniently construct
2191 strings with text properties.
2192
2193 - Function: propertize STRING &rest PROPERTIES
2194
2195 Value is a copy of STRING with text properties assigned as specified
2196 by PROPERTIES. PROPERTIES is a sequence of pairs PROPERTY VALUE, with
2197 PROPERTY being the name of a text property and VALUE being the
2198 specified value of that property. Example:
2199
2200 (propertize "foo" 'face 'bold 'read-only t)
2201
2202 +++
2203 ** push and pop macros.
2204
2205 Simple versions of the push and pop macros of Common Lisp
2206 are now defined in Emacs Lisp. These macros allow only symbols
2207 as the place that holds the list to be changed.
2208
2209 (push NEWELT LISTNAME) add NEWELT to the front of LISTNAME's value.
2210 (pop LISTNAME) return first elt of LISTNAME, and remove it
2211 (thus altering the value of LISTNAME).
2212
2213 ** New dolist and dotimes macros.
2214
2215 Simple versions of the dolist and dotimes macros of Common Lisp
2216 are now defined in Emacs Lisp.
2217
2218 (dolist (VAR LIST [RESULT]) BODY...)
2219 Execute body once for each element of LIST,
2220 using the variable VAR to hold the current element.
2221 Then return the value of RESULT, or nil if RESULT is omitted.
2222
2223 (dotimes (VAR COUNT [RESULT]) BODY...)
2224 Execute BODY with VAR bound to successive integers running from 0,
2225 inclusive, to COUNT, exclusive.
2226 Then return the value of RESULT, or nil if RESULT is omitted.
2227
2228 +++
2229 ** Regular expressions now support Posix character classes such
2230 as [:alpha:], [:space:] and so on.
2231
2232 [:digit:] matches 0 through 9
2233 [:cntrl:] matches ASCII control characters
2234 [:xdigit:] matches 0 through 9, a through f and A through F.
2235 [:blank:] matches space and tab only
2236 [:graph:] matches graphic characters--everything except ASCII control chars,
2237 space, and DEL.
2238 [:print:] matches printing characters--everything except ASCII control chars
2239 and DEL.
2240 [:alnum:] matches letters and digits.
2241 (But at present, for multibyte characters,
2242 it matches anything that has word syntax.)
2243 [:alpha:] matches letters.
2244 (But at present, for multibyte characters,
2245 it matches anything that has word syntax.)
2246 [:ascii:] matches ASCII (unibyte) characters.
2247 [:nonascii:] matches non-ASCII (multibyte) characters.
2248 [:lower:] matches anything lower-case.
2249 [:punct:] matches punctuation.
2250 (But at present, for multibyte characters,
2251 it matches anything that has non-word syntax.)
2252 [:space:] matches anything that has whitespace syntax.
2253 [:upper:] matches anything upper-case.
2254 [:word:] matches anything that has word syntax.
2255
2256 +++
2257 ** Emacs now has built-in hash tables.
2258
2259 The following functions are defined for hash tables:
2260
2261 - Function: make-hash-table ARGS
2262
2263 The argument list ARGS consists of keyword/argument pairs. All arguments
2264 are optional. The following arguments are defined:
2265
2266 :test TEST
2267
2268 TEST must be a symbol specifying how to compare keys. Default is `eql'.
2269 Predefined are `eq', `eql' and `equal'. If TEST is not predefined,
2270 it must have been defined with `define-hash-table-test'.
2271
2272 :size SIZE
2273
2274 SIZE must be an integer > 0 giving a hint to the implementation how
2275 many elements will be put in the hash table. Default size is 65.
2276
2277 :rehash-size REHASH-SIZE
2278
2279 REHASH-SIZE specifies by how much to grow a hash table once it becomes
2280 full. If REHASH-SIZE is an integer, add that to the hash table's old
2281 size to get the new size. Otherwise, REHASH-SIZE must be a float >
2282 1.0, and the new size is computed by multiplying REHASH-SIZE with the
2283 old size. Default rehash size is 1.5.
2284
2285 :rehash-threshold THRESHOLD
2286
2287 THRESHOLD must be a float > 0 and <= 1.0 specifying when to resize the
2288 hash table. It is resized when the ratio of (number of entries) /
2289 (size of hash table) is >= THRESHOLD. Default threshold is 0.8.
2290
2291 :weakness WEAK
2292
2293 WEAK must be either nil, one of the symbols `key, `value',
2294 `key-or-value', `key-and-value', or t, meaning the same as
2295 `key-and-value'. Entries are removed from weak tables during garbage
2296 collection if their key and/or value are not referenced elsewhere
2297 outside of the hash table. Default are non-weak hash tables.
2298
2299 - Function: makehash &optional TEST
2300
2301 Similar to make-hash-table, but only TEST can be specified.
2302
2303 - Function: hash-table-p TABLE
2304
2305 Returns non-nil if TABLE is a hash table object.
2306
2307 - Function: copy-hash-table TABLE
2308
2309 Returns a copy of TABLE. Only the table itself is copied, keys and
2310 values are shared.
2311
2312 - Function: hash-table-count TABLE
2313
2314 Returns the number of entries in TABLE.
2315
2316 - Function: hash-table-rehash-size TABLE
2317
2318 Returns the rehash size of TABLE.
2319
2320 - Function: hash-table-rehash-threshold TABLE
2321
2322 Returns the rehash threshold of TABLE.
2323
2324 - Function: hash-table-rehash-size TABLE
2325
2326 Returns the size of TABLE.
2327
2328 - Function: hash-table-test TABLE
2329
2330 Returns the test TABLE uses to compare keys.
2331
2332 - Function: hash-table-weakness TABLE
2333
2334 Returns the weakness specified for TABLE.
2335
2336 - Function: clrhash TABLE
2337
2338 Clear TABLE.
2339
2340 - Function: gethash KEY TABLE &optional DEFAULT
2341
2342 Look up KEY in TABLE and return its associated VALUE or DEFAULT if
2343 not found.
2344
2345 - Function: puthash KEY VALUE TABLE
2346
2347 Associate KEY with VALUE in TABLE. If KEY is already associated with
2348 another value, replace the old value with VALUE.
2349
2350 - Function: remhash KEY TABLE
2351
2352 Remove KEY from TABLE if it is there.
2353
2354 - Function: maphash FUNCTION TABLE
2355
2356 Call FUNCTION for all elements in TABLE. FUNCTION must take two
2357 arguments KEY and VALUE.
2358
2359 - Function: sxhash OBJ
2360
2361 Return a hash code for Lisp object OBJ.
2362
2363 - Function: define-hash-table-test NAME TEST-FN HASH-FN
2364
2365 Define a new hash table test named NAME. If NAME is specified as
2366 a test in `make-hash-table', the table created will use TEST-FN for
2367 comparing keys, and HASH-FN to compute hash codes for keys. Test
2368 and hash function are stored as symbol property `hash-table-test'
2369 of NAME with a value of (TEST-FN HASH-FN).
2370
2371 TEST-FN must take two arguments and return non-nil if they are the same.
2372
2373 HASH-FN must take one argument and return an integer that is the hash
2374 code of the argument. The function should use the whole range of
2375 integer values for hash code computation, including negative integers.
2376
2377 Example: The following creates a hash table whose keys are supposed to
2378 be strings that are compared case-insensitively.
2379
2380 (defun case-fold-string= (a b)
2381 (compare-strings a nil nil b nil nil t))
2382
2383 (defun case-fold-string-hash (a)
2384 (sxhash (upcase a)))
2385
2386 (define-hash-table-test 'case-fold 'case-fold-string=
2387 'case-fold-string-hash))
2388
2389 (make-hash-table :test 'case-fold)
2390
2391 +++
2392 ** The Lisp reader handles circular structure.
2393
2394 It now works to use the #N= and #N# constructs to represent
2395 circular structures. For example, #1=(a . #1#) represents
2396 a cons cell which is its own cdr.
2397
2398 +++
2399 ** The Lisp printer handles circular structure.
2400
2401 If you bind print-circle to a non-nil value, the Lisp printer outputs
2402 #N= and #N# constructs to represent circular and shared structure.
2403
2404 +++
2405 ** If the second argument to `move-to-column' is anything but nil or
2406 t, that means replace a tab with spaces if necessary to reach the
2407 specified column, but do not add spaces at the end of the line if it
2408 is too short to reach that column.
2409
2410 +++
2411 ** perform-replace has a new feature: the REPLACEMENTS argument may
2412 now be a cons cell (FUNCTION . DATA). This means to call FUNCTION
2413 after each match to get the replacement text. FUNCTION is called with
2414 two arguments: DATA, and the number of replacements already made.
2415
2416 If the FROM-STRING contains any upper-case letters,
2417 perform-replace also turns off `case-fold-search' temporarily
2418 and inserts the replacement text without altering case in it.
2419
2420 +++
2421 ** The function buffer-size now accepts an optional argument
2422 to specify which buffer to return the size of.
2423
2424 +++
2425 ** The calendar motion commands now run the normal hook
2426 calendar-move-hook after moving point.
2427
2428 +++
2429 ** The new variable small-temporary-file-directory specifies a
2430 directory to use for creating temporary files that are likely to be
2431 small. (Certain Emacs features use this directory.) If
2432 small-temporary-file-directory is nil, they use
2433 temporary-file-directory instead.
2434
2435 +++
2436 ** The variable `inhibit-modification-hooks', if non-nil, inhibits all
2437 the hooks that track changes in the buffer. This affects
2438 `before-change-functions' and `after-change-functions', as well as
2439 hooks attached to text properties and overlay properties.
2440
2441 +++
2442 ** assoc-delete-all is a new function that deletes all the
2443 elements of an alist which have a particular value as the car.
2444
2445 +++
2446 ** make-temp-file provides a more reliable way to create a temporary file.
2447
2448 make-temp-file is used like make-temp-name, except that it actually
2449 creates the file before it returns. This prevents a timing error,
2450 ensuring that no other job can use the same name for a temporary file.
2451
2452 +++
2453 ** New exclusive-open feature in `write-region'
2454
2455 The optional seventh arg is now called MUSTBENEW. If non-nil, it insists
2456 on a check for an existing file with the same name. If MUSTBENEW
2457 is `excl', that means to get an error if the file already exists;
2458 never overwrite. If MUSTBENEW is neither nil nor `excl', that means
2459 ask for confirmation before overwriting, but do go ahead and
2460 overwrite the file if the user gives confirmation.
2461
2462 If the MUSTBENEW argument in `write-region' is `excl',
2463 that means to use a special feature in the `open' system call
2464 to get an error if the file exists at that time.
2465 The error reported is `file-already-exists'.
2466
2467 +++
2468 ** Function `format' now handles text properties.
2469
2470 Text properties of the format string are applied to the result string.
2471 If the result string is longer than the format string, text properties
2472 ending at the end of the format string are extended to the end of the
2473 result string.
2474
2475 Text properties from string arguments are applied to the result
2476 string where arguments appear in the result string.
2477
2478 Example:
2479
2480 (let ((s1 "hello, %s")
2481 (s2 "world"))
2482 (put-text-property 0 (length s1) 'face 'bold s1)
2483 (put-text-property 0 (length s2) 'face 'italic s2)
2484 (format s1 s2))
2485
2486 results in a bold-face string with an italic `world' at the end.
2487
2488 +++
2489 ** Messages can now be displayed with text properties.
2490
2491 Text properties are handled as described above for function `format'.
2492 The following example displays a bold-face message with an italic
2493 argument in it.
2494
2495 (let ((msg "hello, %s!")
2496 (arg "world"))
2497 (put-text-property 0 (length msg) 'face 'bold msg)
2498 (put-text-property 0 (length arg) 'face 'italic arg)
2499 (message msg arg))
2500
2501 +++
2502 ** Sound support
2503
2504 Emacs supports playing sound files on GNU/Linux and the free BSDs
2505 (Voxware driver and native BSD driver, aka as Luigi's driver).
2506
2507 Currently supported file formats are RIFF-WAVE (*.wav) and Sun Audio
2508 (*.au). You must configure Emacs with the option `--with-sound=yes'
2509 to enable sound support.
2510
2511 Sound files can be played by calling (play-sound SOUND). SOUND is a
2512 list of the form `(sound PROPERTY...)'. The function is only defined
2513 when sound support is present for the system on which Emacs runs. The
2514 functions runs `play-sound-functions' with one argument which is the
2515 sound to play, before playing the sound.
2516
2517 The following sound properties are supported:
2518
2519 - `:file FILE'
2520
2521 FILE is a file name. If FILE isn't an absolute name, it will be
2522 searched relative to `data-directory'.
2523
2524 - `:data DATA'
2525
2526 DATA is a string containing sound data. Either :file or :data
2527 may be present, but not both.
2528
2529 - `:volume VOLUME'
2530
2531 VOLUME must be an integer in the range 0..100 or a float in the range
2532 0..1. This property is optional.
2533
2534 Other properties are ignored.
2535
2536 ** `multimedia' is a new Finder keyword and Custom group.
2537
2538 ** keywordp is a new predicate to test efficiently for an object being
2539 a keyword symbol.
2540
2541 ** Changes to garbage collection
2542
2543 *** The function garbage-collect now additionally returns the number
2544 of live and free strings.
2545
2546 *** There is a new variable `strings-consed' holding the number of
2547 strings that have been consed so far.
2548
2549 \f
2550 * Lisp-level Display features added after release 2.6 of the Emacs
2551 Lisp Manual
2552
2553 *** On window systems, `glyph-table' is no longer used.
2554
2555 +++
2556 ** Help strings in menu items are now used to provide `help-echo' text.
2557
2558 ** The function `image-size' can be used to determine the size of an
2559 image.
2560
2561 - Function: image-size SPEC &optional PIXELS FRAME
2562
2563 Return the size of an image as a pair (WIDTH . HEIGHT).
2564
2565 SPEC is an image specification. PIXELS non-nil means return sizes
2566 measured in pixels, otherwise return sizes measured in canonical
2567 character units (fractions of the width/height of the frame's default
2568 font). FRAME is the frame on which the image will be displayed.
2569 FRAME nil or omitted means use the selected frame.
2570
2571 ** The function `image-mask-p' can be used to determine if an image
2572 has a mask bitmap.
2573
2574 - Function: image-mask-p SPEC &optional FRAME
2575
2576 Return t if image SPEC has a mask bitmap.
2577 FRAME is the frame on which the image will be displayed. FRAME nil
2578 or omitted means use the selected frame.
2579
2580 +++
2581 ** The function `find-image' can be used to find a usable image
2582 satisfying one of a list of specifications.
2583
2584 +++
2585 ** The STRING argument of `put-image' and `insert-image' is now
2586 optional.
2587
2588 +++
2589 ** Image specifications may contain the property `:ascent center' (see
2590 below).
2591
2592 \f
2593 * New Lisp-level Display features in Emacs 21.1
2594
2595 Note that +++ before an item means the Lisp manual has been updated.
2596 --- means that I have decided it does not need to be in the Lisp manual.
2597 When you add a new item, please add it without either +++ or ---
2598 so I will know I still need to look at it -- rms.
2599
2600 ** The function tty-suppress-bold-inverse-default-colors can be used
2601 to make Emacs avoid displaying text with bold black foreground on TTYs.
2602
2603 Some terminals, notably PC consoles, emulate bold text by displaying
2604 text in brighter colors. On such a console, a bold black foreground
2605 is displayed in a gray color. If this turns out to be hard to read on
2606 your monitor---the problem occurred with the mode line on
2607 laptops---you can instruct Emacs to ignore the text's boldness, and to
2608 just display it black instead.
2609
2610 This situation can't be detected automatically. You will have to put
2611 a line like
2612
2613 (tty-suppress-bold-inverse-default-colors t)
2614
2615 in your `.emacs'.
2616
2617 ** New face implementation.
2618
2619 Emacs faces have been reimplemented from scratch. They don't use XLFD
2620 font names anymore and face merging now works as expected.
2621
2622 +++
2623 *** New faces.
2624
2625 Each face can specify the following display attributes:
2626
2627 1. Font family or fontset alias name.
2628
2629 2. Relative proportionate width, aka character set width or set
2630 width (swidth), e.g. `semi-compressed'.
2631
2632 3. Font height in 1/10pt
2633
2634 4. Font weight, e.g. `bold'.
2635
2636 5. Font slant, e.g. `italic'.
2637
2638 6. Foreground color.
2639
2640 7. Background color.
2641
2642 8. Whether or not characters should be underlined, and in what color.
2643
2644 9. Whether or not characters should be displayed in inverse video.
2645
2646 10. A background stipple, a bitmap.
2647
2648 11. Whether or not characters should be overlined, and in what color.
2649
2650 12. Whether or not characters should be strike-through, and in what
2651 color.
2652
2653 13. Whether or not a box should be drawn around characters, its
2654 color, the width of the box lines, and 3D appearance.
2655
2656 Faces are frame-local by nature because Emacs allows to define the
2657 same named face (face names are symbols) differently for different
2658 frames. Each frame has an alist of face definitions for all named
2659 faces. The value of a named face in such an alist is a Lisp vector
2660 with the symbol `face' in slot 0, and a slot for each each of the face
2661 attributes mentioned above.
2662
2663 There is also a global face alist `face-new-frame-defaults'. Face
2664 definitions from this list are used to initialize faces of newly
2665 created frames.
2666
2667 A face doesn't have to specify all attributes. Those not specified
2668 have a nil value. Faces specifying all attributes are called
2669 `fully-specified'.
2670
2671 +++
2672 *** Face merging.
2673
2674 The display style of a given character in the text is determined by
2675 combining several faces. This process is called `face merging'. Any
2676 aspect of the display style that isn't specified by overlays or text
2677 properties is taken from the `default' face. Since it is made sure
2678 that the default face is always fully-specified, face merging always
2679 results in a fully-specified face.
2680
2681 +++
2682 *** Face realization.
2683
2684 After all face attributes for a character have been determined by
2685 merging faces of that character, that face is `realized'. The
2686 realization process maps face attributes to what is physically
2687 available on the system where Emacs runs. The result is a `realized
2688 face' in form of an internal structure which is stored in the face
2689 cache of the frame on which it was realized.
2690
2691 Face realization is done in the context of the charset of the
2692 character to display because different fonts and encodings are used
2693 for different charsets. In other words, for characters of different
2694 charsets, different realized faces are needed to display them.
2695
2696 Except for composite characters, faces are always realized for a
2697 specific character set and contain a specific font, even if the face
2698 being realized specifies a fontset. The reason is that the result of
2699 the new font selection stage is better than what can be done with
2700 statically defined font name patterns in fontsets.
2701
2702 In unibyte text, Emacs' charsets aren't applicable; function
2703 `char-charset' reports ASCII for all characters, including those >
2704 0x7f. The X registry and encoding of fonts to use is determined from
2705 the variable `face-default-registry' in this case. The variable is
2706 initialized at Emacs startup time from the font the user specified for
2707 Emacs.
2708
2709 Currently all unibyte text, i.e. all buffers with
2710 `enable-multibyte-characters' nil are displayed with fonts of the same
2711 registry and encoding `face-default-registry'. This is consistent
2712 with the fact that languages can also be set globally, only.
2713
2714 ++++
2715 **** Clearing face caches.
2716
2717 The Lisp function `clear-face-cache' can be called to clear face caches
2718 on all frames. If called with a non-nil argument, it will also unload
2719 unused fonts.
2720
2721 +++
2722 *** Font selection.
2723
2724 Font selection tries to find the best available matching font for a
2725 given (charset, face) combination. This is done slightly differently
2726 for faces specifying a fontset, or a font family name.
2727
2728 If the face specifies a fontset name, that fontset determines a
2729 pattern for fonts of the given charset. If the face specifies a font
2730 family, a font pattern is constructed. Charset symbols have a
2731 property `x-charset-registry' for that purpose that maps a charset to
2732 an XLFD registry and encoding in the font pattern constructed.
2733
2734 Available fonts on the system on which Emacs runs are then matched
2735 against the font pattern. The result of font selection is the best
2736 match for the given face attributes in this font list.
2737
2738 Font selection can be influenced by the user.
2739
2740 The user can specify the relative importance he gives the face
2741 attributes width, height, weight, and slant by setting
2742 face-font-selection-order (faces.el) to a list of face attribute
2743 names. The default is (:width :height :weight :slant), and means
2744 that font selection first tries to find a good match for the font
2745 width specified by a face, then---within fonts with that width---tries
2746 to find a best match for the specified font height, etc.
2747
2748 Setting `face-alternative-font-family-alist' allows the user to
2749 specify alternative font families to try if a family specified by a
2750 face doesn't exist.
2751
2752 +++
2753 **** Scalable fonts
2754
2755 Emacs can make use of scalable fonts but doesn't do so by default,
2756 since the use of too many or too big scalable fonts may crash XFree86
2757 servers.
2758
2759 To enable scalable font use, set the variable
2760 `scalable-fonts-allowed'. A value of nil, the default, means never use
2761 scalable fonts. A value of t means any scalable font may be used.
2762 Otherwise, the value must be a list of regular expressions. A
2763 scalable font may then be used if it matches a regular expression from
2764 that list. Example:
2765
2766 (setq scalable-fonts-allowed '("muleindian-2$"))
2767
2768 allows the use of scalable fonts with registry `muleindian-2'.
2769
2770 +++
2771 *** Functions and variables related to font selection.
2772
2773 - Function: x-family-fonts &optional FAMILY FRAME
2774
2775 Return a list of available fonts of family FAMILY on FRAME. If FAMILY
2776 is omitted or nil, list all families. Otherwise, FAMILY must be a
2777 string, possibly containing wildcards `?' and `*'.
2778
2779 If FRAME is omitted or nil, use the selected frame. Each element of
2780 the result is a vector [FAMILY WIDTH POINT-SIZE WEIGHT SLANT FIXED-P
2781 FULL REGISTRY-AND-ENCODING]. FAMILY is the font family name.
2782 POINT-SIZE is the size of the font in 1/10 pt. WIDTH, WEIGHT, and
2783 SLANT are symbols describing the width, weight and slant of the font.
2784 These symbols are the same as for face attributes. FIXED-P is non-nil
2785 if the font is fixed-pitch. FULL is the full name of the font, and
2786 REGISTRY-AND-ENCODING is a string giving the registry and encoding of
2787 the font. The result list is sorted according to the current setting
2788 of the face font sort order.
2789
2790 - Function: x-font-family-list
2791
2792 Return a list of available font families on FRAME. If FRAME is
2793 omitted or nil, use the selected frame. Value is a list of conses
2794 (FAMILY . FIXED-P) where FAMILY is a font family, and FIXED-P is
2795 non-nil if fonts of that family are fixed-pitch.
2796
2797 - Variable: font-list-limit
2798
2799 Limit for font matching. If an integer > 0, font matching functions
2800 won't load more than that number of fonts when searching for a
2801 matching font. The default is currently 100.
2802
2803 +++
2804 *** Setting face attributes.
2805
2806 For the most part, the new face implementation is interface-compatible
2807 with the old one. Old face attribute related functions are now
2808 implemented in terms of the new functions `set-face-attribute' and
2809 `face-attribute'.
2810
2811 Face attributes are identified by their names which are keyword
2812 symbols. All attributes can be set to `unspecified'.
2813
2814 The following attributes are recognized:
2815
2816 `:family'
2817
2818 VALUE must be a string specifying the font family, e.g. ``courier'',
2819 or a fontset alias name. If a font family is specified, wild-cards `*'
2820 and `?' are allowed.
2821
2822 `:width'
2823
2824 VALUE specifies the relative proportionate width of the font to use.
2825 It must be one of the symbols `ultra-condensed', `extra-condensed',
2826 `condensed', `semi-condensed', `normal', `semi-expanded', `expanded',
2827 `extra-expanded', or `ultra-expanded'.
2828
2829 `:height'
2830
2831 VALUE must be either an integer specifying the height of the font to use
2832 in 1/10 pt, a floating point number specifying the amount by which to
2833 scale any underlying face, or a function, which is called with the old
2834 height (from the underlying face), and should return the new height.
2835
2836 `:weight'
2837
2838 VALUE specifies the weight of the font to use. It must be one of the
2839 symbols `ultra-bold', `extra-bold', `bold', `semi-bold', `normal',
2840 `semi-light', `light', `extra-light', `ultra-light'.
2841
2842 `:slant'
2843
2844 VALUE specifies the slant of the font to use. It must be one of the
2845 symbols `italic', `oblique', `normal', `reverse-italic', or
2846 `reverse-oblique'.
2847
2848 `:foreground', `:background'
2849
2850 VALUE must be a color name, a string.
2851
2852 `:underline'
2853
2854 VALUE specifies whether characters in FACE should be underlined. If
2855 VALUE is t, underline with foreground color of the face. If VALUE is
2856 a string, underline with that color. If VALUE is nil, explicitly
2857 don't underline.
2858
2859 `:overline'
2860
2861 VALUE specifies whether characters in FACE should be overlined. If
2862 VALUE is t, overline with foreground color of the face. If VALUE is a
2863 string, overline with that color. If VALUE is nil, explicitly don't
2864 overline.
2865
2866 `:strike-through'
2867
2868 VALUE specifies whether characters in FACE should be drawn with a line
2869 striking through them. If VALUE is t, use the foreground color of the
2870 face. If VALUE is a string, strike-through with that color. If VALUE
2871 is nil, explicitly don't strike through.
2872
2873 `:box'
2874
2875 VALUE specifies whether characters in FACE should have a box drawn
2876 around them. If VALUE is nil, explicitly don't draw boxes. If
2877 VALUE is t, draw a box with lines of width 1 in the foreground color
2878 of the face. If VALUE is a string, the string must be a color name,
2879 and the box is drawn in that color with a line width of 1. Otherwise,
2880 VALUE must be a property list of the form `(:line-width WIDTH
2881 :color COLOR :style STYLE)'. If a keyword/value pair is missing from
2882 the property list, a default value will be used for the value, as
2883 specified below. WIDTH specifies the width of the lines to draw; it
2884 defaults to 1. COLOR is the name of the color to draw in, default is
2885 the foreground color of the face for simple boxes, and the background
2886 color of the face for 3D boxes. STYLE specifies whether a 3D box
2887 should be draw. If STYLE is `released-button', draw a box looking
2888 like a released 3D button. If STYLE is `pressed-button' draw a box
2889 that appears like a pressed button. If STYLE is nil, the default if
2890 the property list doesn't contain a style specification, draw a 2D
2891 box.
2892
2893 `:inverse-video'
2894
2895 VALUE specifies whether characters in FACE should be displayed in
2896 inverse video. VALUE must be one of t or nil.
2897
2898 `:stipple'
2899
2900 If VALUE is a string, it must be the name of a file of pixmap data.
2901 The directories listed in the `x-bitmap-file-path' variable are
2902 searched. Alternatively, VALUE may be a list of the form (WIDTH
2903 HEIGHT DATA) where WIDTH and HEIGHT are the size in pixels, and DATA
2904 is a string containing the raw bits of the bitmap. VALUE nil means
2905 explicitly don't use a stipple pattern.
2906
2907 For convenience, attributes `:family', `:width', `:height', `:weight',
2908 and `:slant' may also be set in one step from an X font name:
2909
2910 `:font'
2911
2912 Set font-related face attributes from VALUE. VALUE must be a valid
2913 XLFD font name. If it is a font name pattern, the first matching font
2914 is used--this is for compatibility with the behavior of previous
2915 versions of Emacs.
2916
2917 For compatibility with Emacs 20, keywords `:bold' and `:italic' can
2918 be used to specify that a bold or italic font should be used. VALUE
2919 must be t or nil in that case. A value of `unspecified' is not allowed."
2920
2921 Please see also the documentation of `set-face-attribute' and
2922 `defface'.
2923
2924 `:inherit'
2925
2926 VALUE is the name of a face from which to inherit attributes, or a list
2927 of face names. Attributes from inherited faces are merged into the face
2928 like an underlying face would be, with higher priority than underlying faces.
2929
2930 *** Face attributes and X resources
2931
2932 The following X resource names can be used to set face attributes
2933 from X resources:
2934
2935 Face attribute X resource class
2936 -----------------------------------------------------------------------
2937 :family attributeFamily . Face.AttributeFamily
2938 :width attributeWidth Face.AttributeWidth
2939 :height attributeHeight Face.AttributeHeight
2940 :weight attributeWeight Face.AttributeWeight
2941 :slant attributeSlant Face.AttributeSlant
2942 foreground attributeForeground Face.AttributeForeground
2943 :background attributeBackground . Face.AttributeBackground
2944 :overline attributeOverline Face.AttributeOverline
2945 :strike-through attributeStrikeThrough Face.AttributeStrikeThrough
2946 :box attributeBox Face.AttributeBox
2947 :underline attributeUnderline Face.AttributeUnderline
2948 :inverse-video attributeInverse Face.AttributeInverse
2949 :stipple attributeStipple Face.AttributeStipple
2950 or attributeBackgroundPixmap
2951 Face.AttributeBackgroundPixmap
2952 :font attributeFont Face.AttributeFont
2953 :bold attributeBold Face.AttributeBold
2954 :italic attributeItalic . Face.AttributeItalic
2955 :font attributeFont Face.AttributeFont
2956
2957 +++
2958 *** Text property `face'.
2959
2960 The value of the `face' text property can now be a single face
2961 specification or a list of such specifications. Each face
2962 specification can be
2963
2964 1. A symbol or string naming a Lisp face.
2965
2966 2. A property list of the form (KEYWORD VALUE ...) where each
2967 KEYWORD is a face attribute name, and VALUE is an appropriate value
2968 for that attribute. Please see the doc string of `set-face-attribute'
2969 for face attribute names.
2970
2971 3. Conses of the form (FOREGROUND-COLOR . COLOR) or
2972 (BACKGROUND-COLOR . COLOR) where COLOR is a color name. This is
2973 for compatibility with previous Emacs versions.
2974
2975 +++
2976 ** Support functions for colors on text-only terminals.
2977
2978 The function `tty-color-define' can be used to define colors for use
2979 on TTY and MSDOS frames. It maps a color name to a color number on
2980 the terminal. Emacs defines a couple of common color mappings by
2981 default. You can get defined colors with a call to
2982 `defined-colors'. The function `tty-color-clear' can be
2983 used to clear the mapping table.
2984
2985 ** Unified support for colors independent of frame type.
2986
2987 The new functions `defined-colors', `color-defined-p', `color-values',
2988 and `display-color-p' work for any type of frame. On frames whose
2989 type is neither x nor w32, these functions transparently map X-style
2990 color specifications to the closest colors supported by the frame
2991 display. Lisp programs should use these new functions instead of the
2992 old `x-defined-colors', `x-color-defined-p', `x-color-values', and
2993 `x-display-color-p'. (The old function names are still available for
2994 compatibility; they are now aliases of the new names.) Lisp programs
2995 should no more look at the value of the variable window-system to
2996 modify their color-related behavior.
2997
2998 The primitives `color-gray-p' and `color-supported-p' also work for
2999 any frame type.
3000
3001 ** Platform-independent functions to describe display capabilities.
3002
3003 The new functions `display-mouse-p', `display-popup-menus-p',
3004 `display-graphic-p', `display-selections-p', `display-screens',
3005 `display-pixel-width', `display-pixel-height', `display-mm-width',
3006 `display-mm-height', `display-backing-store', `display-save-under',
3007 `display-planes', `display-color-cells', `display-visual-class', and
3008 `display-grayscale-p' describe the basic capabilities of a particular
3009 display. Lisp programs should call these functions instead of testing
3010 the value of the variables `window-system' or `system-type', or calling
3011 platform-specific functions such as `x-display-pixel-width'.
3012
3013 +++
3014 ** The minibuffer prompt is now actually inserted in the minibuffer.
3015
3016 This makes it possible to scroll through the prompt, if you want to.
3017
3018 The function minubuffer-prompt-end returns the current position of the
3019 end of the minibuffer prompt, if the minibuffer is current.
3020 Otherwise, it returns zero.
3021
3022 ** New `field' abstraction in buffers.
3023
3024 There is now code to support an abstraction called `fields' in emacs
3025 buffers. A field is a contiguous region of text with the same `field'
3026 property (which can be a text property or an overlay).
3027
3028 Many emacs functions, such as forward-word, forward-sentence,
3029 forward-paragraph, beginning-of-line, etc., stop moving when they come
3030 to the boundary between fields; beginning-of-line and end-of-line will
3031 not let the point move past the field boundary, but other movement
3032 commands continue into the next field if repeated. Stopping at field
3033 boundaries can be suppressed programmatically by binding
3034 `inhibit-field-text-motion' to a non-nil value around calls to these
3035 functions.
3036
3037 Now that the minibuffer prompt is inserted into the minibuffer, it is in
3038 a separate field from the user-input part of the buffer, so that common
3039 editing commands treat the user's text separately from the prompt.
3040
3041 The following functions are defined for operating on fields:
3042
3043 - Function: constrain-to-field NEW-POS OLD-POS &optional ESCAPE-FROM-EDGE ONLY-IN-LINE INHIBIT-CAPTURE-PROPERTY
3044
3045 Return the position closest to NEW-POS that is in the same field as OLD-POS.
3046
3047 A field is a region of text with the same `field' property.
3048 If NEW-POS is nil, then the current point is used instead, and set to the
3049 constrained position if that is is different.
3050
3051 If OLD-POS is at the boundary of two fields, then the allowable
3052 positions for NEW-POS depends on the value of the optional argument
3053 ESCAPE-FROM-EDGE: If ESCAPE-FROM-EDGE is nil, then NEW-POS is
3054 constrained to the field that has the same `field' char-property
3055 as any new characters inserted at OLD-POS, whereas if ESCAPE-FROM-EDGE
3056 is non-nil, NEW-POS is constrained to the union of the two adjacent
3057 fields. Additionally, if two fields are separated by another field with
3058 the special value `boundary', then any point within this special field is
3059 also considered to be `on the boundary'.
3060
3061 If the optional argument ONLY-IN-LINE is non-nil and constraining
3062 NEW-POS would move it to a different line, NEW-POS is returned
3063 unconstrained. This useful for commands that move by line, like
3064 C-n or C-a, which should generally respect field boundaries
3065 only in the case where they can still move to the right line.
3066
3067 If the optional argument INHIBIT-CAPTURE-PROPERTY is non-nil, and OLD-POS has
3068 a non-nil property of that name, then any field boundaries are ignored.
3069
3070 Field boundaries are not noticed if `inhibit-field-text-motion' is non-nil.
3071
3072 - Function: delete-field &optional POS
3073
3074 Delete the field surrounding POS.
3075 A field is a region of text with the same `field' property.
3076 If POS is nil, the value of point is used for POS.
3077
3078 - Function: field-beginning &optional POS ESCAPE-FROM-EDGE
3079
3080 Return the beginning of the field surrounding POS.
3081 A field is a region of text with the same `field' property.
3082 If POS is nil, the value of point is used for POS.
3083 If ESCAPE-FROM-EDGE is non-nil and POS is at the beginning of its
3084 field, then the beginning of the *previous* field is returned.
3085
3086 - Function: field-end &optional POS ESCAPE-FROM-EDGE
3087
3088 Return the end of the field surrounding POS.
3089 A field is a region of text with the same `field' property.
3090 If POS is nil, the value of point is used for POS.
3091 If ESCAPE-FROM-EDGE is non-nil and POS is at the end of its field,
3092 then the end of the *following* field is returned.
3093
3094 - Function: field-string &optional POS
3095
3096 Return the contents of the field surrounding POS as a string.
3097 A field is a region of text with the same `field' property.
3098 If POS is nil, the value of point is used for POS.
3099
3100 - Function: field-string-no-properties &optional POS
3101
3102 Return the contents of the field around POS, without text-properties.
3103 A field is a region of text with the same `field' property.
3104 If POS is nil, the value of point is used for POS.
3105
3106 +++
3107 ** Image support.
3108
3109 Emacs can now display images. Images are inserted into text by giving
3110 strings or buffer text a `display' text property containing one of
3111 (AREA IMAGE) or IMAGE. The display of the `display' property value
3112 replaces the display of the characters having that property.
3113
3114 If the property value has the form (AREA IMAGE), AREA must be one of
3115 `(margin left-margin)', `(margin right-margin)' or `(margin nil)'. If
3116 AREA is `(margin nil)', IMAGE will be displayed in the text area of a
3117 window, otherwise it will be displayed in the left or right marginal
3118 area.
3119
3120 IMAGE is an image specification.
3121
3122 *** Image specifications
3123
3124 Image specifications are lists of the form `(image PROPS)' where PROPS
3125 is a property list whose keys are keyword symbols. Each
3126 specifications must contain a property `:type TYPE' with TYPE being a
3127 symbol specifying the image type, e.g. `xbm'. Properties not
3128 described below are ignored.
3129
3130 The following is a list of properties all image types share.
3131
3132 `:ascent ASCENT'
3133
3134 ASCENT must be a number in the range 0..100, or the symbol `center'.
3135 If it is a number, it specifies the percentage of the image's height
3136 to use for its ascent.
3137
3138 If not specified, ASCENT defaults to the value 50 which means that the
3139 image will be centered with the base line of the row it appears in.
3140
3141 If ASCENT is `center' the image is vertically centered around a
3142 centerline which is the vertical center of text drawn at the position
3143 of the image, in the manner specified by the text properties and
3144 overlays that apply to the image.
3145
3146 `:margin MARGIN'
3147
3148 MARGIN must be a number >= 0 specifying how many pixels to put as
3149 margin around the image. Default is 0.
3150
3151 `:relief RELIEF'
3152
3153 RELIEF is analogous to the `:relief' attribute of faces. Puts a relief
3154 around an image.
3155
3156 `:algorithm ALGO'
3157
3158 Apply an image algorithm to the image before displaying it.
3159
3160 ALGO `laplace' or `emboss' means apply a Laplace or ``emboss''
3161 edge-detection algorithm to the image.
3162
3163 ALGO `(edge-detection :matrix MATRIX :color-adjust ADJUST)' means
3164 apply a general edge-detection algorithm. MATRIX must be either a
3165 nine-element list or a nine-element vector of numbers. A pixel at
3166 position x/y in the transformed image is computed from original pixels
3167 around that position. MATRIX specifies, for each pixel in the
3168 neighborhood of x/y, a factor with which that pixel will influence the
3169 transformed pixel; element 0 specifies the factor for the pixel at
3170 x-1/y-1, element 1 the factor for the pixel at x/y-1 etc. as shown
3171 below.
3172
3173 (x-1/y-1 x/y-1 x+1/y-1
3174 x-1/y x/y x+1/y
3175 x-1/y+1 x/y+1 x+1/y+1)
3176
3177 The resulting pixel is computed from the color intensity of the color
3178 resulting from summing up the RGB values of surrounding pixels,
3179 multiplied by the specified factors, and dividing that sum by the sum
3180 of the factors' absolute values.
3181
3182 Laplace edge-detection currently uses a matrix of
3183
3184 (1 0 0
3185 0 0 0
3186 9 9 -1)
3187
3188 Emboss edge-detection uses a matrix of
3189
3190 ( 2 -1 0
3191 -1 0 1
3192 0 1 -2)
3193
3194 ALGO `disabled' means transform the image so that it looks
3195 ``disabled''.
3196
3197 `:mask MASK'
3198
3199 If MASK is `heuristic' or `(heuristic BG)', build a clipping mask for
3200 the image, so that the background of a frame is visible behind the
3201 image. If BG is not specified, or if BG is t, determine the
3202 background color of the image by looking at the 4 corners of the
3203 image, assuming the most frequently occuring color from the corners is
3204 the background color of the image. Otherwise, BG must be a list `(RED
3205 GREEN BLUE)' specifying the color to assume for the background of the
3206 image.
3207
3208 If MASK is nil, remove a mask from the image, if it has one. Images
3209 in some formats include a mask which can be removed by specifying
3210 `:mask nil'.
3211
3212 `:file FILE'
3213
3214 Load image from FILE. If FILE is not absolute after expanding it,
3215 search for the image in `data-directory'. Some image types support
3216 building images from data. When this is done, no `:file' property
3217 may be present in the image specification.
3218
3219 `:data DATA'
3220
3221 Get image data from DATA. (As of this writing, this is not yet
3222 supported for image type `postscript'). Either :file or :data may be
3223 present in an image specification, but not both. All image types
3224 support strings as DATA, some types allow additional types of DATA.
3225
3226 *** Supported image types
3227
3228 **** XBM, image type `xbm'.
3229
3230 XBM images don't require an external library. Additional image
3231 properties supported are
3232
3233 `:foreground FG'
3234
3235 FG must be a string specifying the image foreground color. Default
3236 is the frame's foreground.
3237
3238 `:background FG'
3239
3240 BG must be a string specifying the image foreground color. Default is
3241 the frame's background color.
3242
3243 XBM images can be constructed from data instead of file. In this
3244 case, the image specification must contain the following properties
3245 instead of a `:file' property.
3246
3247 `:width WIDTH'
3248
3249 WIDTH specifies the width of the image in pixels.
3250
3251 `:height HEIGHT'
3252
3253 HEIGHT specifies the height of the image in pixels.
3254
3255 `:data DATA'
3256
3257 DATA must be either
3258
3259 1. a string large enough to hold the bitmap data, i.e. it must
3260 have a size >= (WIDTH + 7) / 8 * HEIGHT
3261
3262 2. a bool-vector of size >= WIDTH * HEIGHT
3263
3264 3. a vector of strings or bool-vectors, one for each line of the
3265 bitmap.
3266
3267 4. a string that's an in-memory XBM file. Neither width nor
3268 height may be specified in this case because these are defined
3269 in the file.
3270
3271 **** XPM, image type `xpm'
3272
3273 XPM images require the external library `libXpm', package
3274 `xpm-3.4k.tar.gz', version 3.4k or later. Make sure the library is
3275 found when Emacs is configured by supplying appropriate paths via
3276 `--x-includes' and `--x-libraries'.
3277
3278 Additional image properties supported are:
3279
3280 `:color-symbols SYMBOLS'
3281
3282 SYMBOLS must be a list of pairs (NAME . COLOR), with NAME being the
3283 name of color as it appears in an XPM file, and COLOR being an X color
3284 name.
3285
3286 XPM images can be built from memory instead of files. In that case,
3287 add a `:data' property instead of a `:file' property.
3288
3289 The XPM library uses libz in its implementation so that it is able
3290 to display compressed images.
3291
3292 **** PBM, image type `pbm'
3293
3294 PBM images don't require an external library. Color, gray-scale and
3295 mono images are supported. There are no additional image properties
3296 defined.
3297
3298 **** JPEG, image type `jpeg'
3299
3300 Support for JPEG images requires the external library `libjpeg',
3301 package `jpegsrc.v6a.tar.gz', or later. Additional image properties
3302 are:
3303
3304 **** TIFF, image type `tiff'
3305
3306 Support for TIFF images requires the external library `libtiff',
3307 package `tiff-v3.4-tar.gz', or later. There are no additional image
3308 properties defined.
3309
3310 **** GIF, image type `gif'
3311
3312 Support for GIF images requires the external library `libungif', package
3313 `libungif-4.1.0', or later.
3314
3315 Additional image properties supported are:
3316
3317 `:index INDEX'
3318
3319 INDEX must be an integer >= 0. Load image number INDEX from a
3320 multi-image GIF file. An error is signalled if INDEX is too large.
3321
3322 This could be used to implement limited support for animated GIFs.
3323 For example, the following function displays a multi-image GIF file
3324 at point-min in the current buffer, switching between sub-images
3325 every 0.1 seconds.
3326
3327 (defun show-anim (file max)
3328 "Display multi-image GIF file FILE which contains MAX subimages."
3329 (display-anim (current-buffer) file 0 max t))
3330
3331 (defun display-anim (buffer file idx max first-time)
3332 (when (= idx max)
3333 (setq idx 0))
3334 (let ((img (create-image file nil nil :index idx)))
3335 (save-excursion
3336 (set-buffer buffer)
3337 (goto-char (point-min))
3338 (unless first-time (delete-char 1))
3339 (insert-image img "x"))
3340 (run-with-timer 0.1 nil 'display-anim buffer file (1+ idx) max nil)))
3341
3342 **** PNG, image type `png'
3343
3344 Support for PNG images requires the external library `libpng',
3345 package `libpng-1.0.2.tar.gz', or later. There are no additional image
3346 properties defined.
3347
3348 **** Ghostscript, image type `postscript'.
3349
3350 Additional image properties supported are:
3351
3352 `:pt-width WIDTH'
3353
3354 WIDTH is width of the image in pt (1/72 inch). WIDTH must be an
3355 integer. This is a required property.
3356
3357 `:pt-height HEIGHT'
3358
3359 HEIGHT specifies the height of the image in pt (1/72 inch). HEIGHT
3360 must be a integer. This is an required property.
3361
3362 `:bounding-box BOX'
3363
3364 BOX must be a list or vector of 4 integers giving the bounding box of
3365 the PS image, analogous to the `BoundingBox' comment found in PS
3366 files. This is an required property.
3367
3368 Part of the Ghostscript interface is implemented in Lisp. See
3369 lisp/gs.el.
3370
3371 *** Lisp interface.
3372
3373 The variable `image-types' contains a list of those image types
3374 which are supported in the current configuration.
3375
3376 Images are stored in an image cache and removed from the cache when
3377 they haven't been displayed for `image-cache-eviction-delay seconds.
3378 The function `clear-image-cache' can be used to clear the image cache
3379 manually. Images in the cache are compared with `equal', i.e. all
3380 images with `equal' specifications share the same image.
3381
3382 *** Simplified image API, image.el
3383
3384 The new Lisp package image.el contains functions that simplify image
3385 creation and putting images into text. The function `create-image'
3386 can be used to create images. The macro `defimage' can be used to
3387 define an image based on available image types. The functions
3388 `put-image' and `insert-image' can be used to insert an image into a
3389 buffer.
3390
3391 +++
3392 ** Display margins.
3393
3394 Windows can now have margins which are used for special text
3395 and images.
3396
3397 To give a window margins, either set the buffer-local variables
3398 `left-margin-width' and `right-margin-width', or call
3399 `set-window-margins'. The function `window-margins' can be used to
3400 obtain the current settings. To make `left-margin-width' and
3401 `right-margin-width' take effect, you must set them before displaying
3402 the buffer in a window, or use `set-window-buffer' to force an update
3403 of the display margins.
3404
3405 You can put text in margins by giving it a `display' text property
3406 containing a pair of the form `(LOCATION . VALUE)', where LOCATION is
3407 one of `left-margin' or `right-margin' or nil. VALUE can be either a
3408 string, an image specification or a stretch specification (see later
3409 in this file).
3410
3411 +++
3412 ** Help display
3413
3414 Emacs displays short help messages in the echo area, when the mouse
3415 moves over a tool-bar item or a piece of text that has a text property
3416 `help-echo'. This feature also applies to strings in the mode line
3417 that have a `help-echo' property.
3418
3419 If the value of the `help-echo' property is a function, that function
3420 is called with three arguments WINDOW, OBJECT and POSITION. WINDOW is
3421 the window in which the help was found.
3422
3423 If OBJECT is a buffer, POS is the position in the buffer where the
3424 `help-echo' text property was found.
3425
3426 If OBJECT is an overlay, that overlay has a `help-echo' property, and
3427 POS is the position in the overlay's buffer under the mouse.
3428
3429 If OBJECT is a string (an overlay string or a string displayed with
3430 the `display' property), POS is the position in that string under the
3431 mouse.
3432
3433 If the value of the `help-echo' property is neither a function nor a
3434 string, it is evaluated to obtain a help string.
3435
3436 For tool-bar and menu-bar items, their key definition is used to
3437 determine the help to display. If their definition contains a
3438 property `:help FORM', FORM is evaluated to determine the help string.
3439 For tool-bar items without a help form, the caption of the item is
3440 used as help string.
3441
3442 The hook `show-help-function' can be set to a function that displays
3443 the help string differently. For example, enabling a tooltip window
3444 causes the help display to appear there instead of in the echo area.
3445
3446 +++
3447 ** Vertical fractional scrolling.
3448
3449 The display of text in windows can be scrolled smoothly in pixels.
3450 This is useful, for example, for making parts of large images visible.
3451
3452 The function `window-vscroll' returns the current value of vertical
3453 scrolling, a non-negative fraction of the canonical character height.
3454 The function `set-window-vscroll' can be used to set the vertical
3455 scrolling value. Here is an example of how these function might be
3456 used.
3457
3458 (global-set-key [A-down]
3459 #'(lambda ()
3460 (interactive)
3461 (set-window-vscroll (selected-window)
3462 (+ 0.5 (window-vscroll)))))
3463 (global-set-key [A-up]
3464 #'(lambda ()
3465 (interactive)
3466 (set-window-vscroll (selected-window)
3467 (- (window-vscroll) 0.5)))))
3468
3469 +++
3470 ** New hook `fontification-functions'.
3471
3472 Functions from `fontification-functions' are called from redisplay
3473 when it encounters a region of text that is not yet fontified. This
3474 variable automatically becomes buffer-local when set. Each function
3475 is called with one argument, POS.
3476
3477 At least one of the hook functions should fontify one or more
3478 characters starting at POS in the current buffer. It should mark them
3479 as fontified by giving them a non-nil value of the `fontified' text
3480 property. It may be reasonable for these functions to check for the
3481 `fontified' property and not put it back on, but they do not have to.
3482
3483 +++
3484 ** Tool bar support.
3485
3486 Emacs supports a tool bar at the top of a frame under X. The frame
3487 parameter `tool-bar-lines' (X resource "toolBar", class "ToolBar")
3488 controls how may lines to reserve for the tool bar. A zero value
3489 suppresses the tool bar. If the value is non-zero and
3490 `auto-resize-tool-bars' is non-nil the tool bar's size will be changed
3491 automatically so that all tool bar items are visible.
3492
3493 *** Tool bar item definitions
3494
3495 Tool bar items are defined using `define-key' with a prefix-key
3496 `tool-bar'. For example `(define-key global-map [tool-bar item1] ITEM)'
3497 where ITEM is a list `(menu-item CAPTION BINDING PROPS...)'.
3498
3499 CAPTION is the caption of the item, If it's not a string, it is
3500 evaluated to get a string. The caption is currently not displayed in
3501 the tool bar, but it is displayed if the item doesn't have a `:help'
3502 property (see below).
3503
3504 BINDING is the tool bar item's binding. Tool bar items with keymaps as
3505 binding are currently ignored.
3506
3507 The following properties are recognized:
3508
3509 `:enable FORM'.
3510
3511 FORM is evaluated and specifies whether the tool bar item is enabled
3512 or disabled.
3513
3514 `:visible FORM'
3515
3516 FORM is evaluated and specifies whether the tool bar item is displayed.
3517
3518 `:filter FUNCTION'
3519
3520 FUNCTION is called with one parameter, the same list BINDING in which
3521 FUNCTION is specified as the filter. The value FUNCTION returns is
3522 used instead of BINDING to display this item.
3523
3524 `:button (TYPE SELECTED)'
3525
3526 TYPE must be one of `:radio' or `:toggle'. SELECTED is evaluated
3527 and specifies whether the button is selected (pressed) or not.
3528
3529 `:image IMAGES'
3530
3531 IMAGES is either a single image specification or a vector of four
3532 image specifications. If it is a vector, this table lists the
3533 meaning of each of the four elements:
3534
3535 Index Use when item is
3536 ----------------------------------------
3537 0 enabled and selected
3538 1 enabled and deselected
3539 2 disabled and selected
3540 3 disabled and deselected
3541
3542 If IMAGE is a single image specification, a Laplace edge-detection
3543 algorithm is used on that image to draw the image in disabled state.
3544
3545 `:help HELP-STRING'.
3546
3547 Gives a help string to display for the tool bar item. This help
3548 is displayed when the mouse is moved over the item.
3549
3550 The function `toolbar-add-item' is a convenience function for adding
3551 toolbar items generally, and `tool-bar-add-item-from-menu' can be used
3552 to define a toolbar item with a binding copied from an item on the
3553 menu bar.
3554
3555 *** Tool-bar-related variables.
3556
3557 If `auto-resize-tool-bar' is non-nil, the tool bar will automatically
3558 resize to show all defined tool bar items. It will never grow larger
3559 than 1/4 of the frame's size.
3560
3561 If `auto-raise-tool-bar-buttons' is non-nil, tool bar buttons will be
3562 raised when the mouse moves over them.
3563
3564 You can add extra space between tool bar items by setting
3565 `tool-bar-button-margin' to a positive integer specifying a number of
3566 pixels. Default is 1.
3567
3568 You can change the shadow thickness of tool bar buttons by setting
3569 `tool-bar-button-relief' to an integer. Default is 3.
3570
3571 *** Tool-bar clicks with modifiers.
3572
3573 You can bind commands to clicks with control, shift, meta etc. on
3574 a tool bar item. If
3575
3576 (define-key global-map [tool-bar shell]
3577 '(menu-item "Shell" shell
3578 :image (image :type xpm :file "shell.xpm")))
3579
3580 is the original tool bar item definition, then
3581
3582 (define-key global-map [tool-bar S-shell] 'some-command)
3583
3584 makes a binding to run `some-command' for a shifted click on the same
3585 item.
3586
3587 ** Mode line changes.
3588
3589 +++
3590 *** Mouse-sensitive mode line.
3591
3592 The mode line can be made mouse-sensitive by displaying strings there
3593 that have a `local-map' text property. There are three ways to display
3594 a string with a `local-map' property in the mode line.
3595
3596 1. The mode line spec contains a variable whose string value has
3597 a `local-map' text property.
3598
3599 2. The mode line spec contains a format specifier (e.g. `%12b'), and
3600 that format specifier has a `local-map' property.
3601
3602 3. The mode line spec contains a list containing `:eval FORM'. FORM
3603 is evaluated. If the result is a string, and that string has a
3604 `local-map' property.
3605
3606 The same mechanism is used to determine the `face' and `help-echo'
3607 properties of strings in the mode line. See `bindings.el' for an
3608 example.
3609
3610 *** If a mode line element has the form `(:eval FORM)', FORM is
3611 evaluated and the result is used as mode line element.
3612
3613 +++
3614 *** You can suppress mode-line display by setting the buffer-local
3615 variable mode-line-format to nil.
3616
3617 +++
3618 *** A headerline can now be displayed at the top of a window.
3619
3620 This mode line's contents are controlled by the new variable
3621 `header-line-format' and `default-header-line-format' which are
3622 completely analogous to `mode-line-format' and
3623 `default-mode-line-format'. A value of nil means don't display a top
3624 line.
3625
3626 The appearance of top mode lines is controlled by the face
3627 `header-line'.
3628
3629 The function `coordinates-in-window-p' returns `header-line' for a
3630 position in the header-line.
3631
3632 +++
3633 ** Text property `display'
3634
3635 The `display' text property is used to insert images into text,
3636 replace text with other text, display text in marginal area, and it is
3637 also used to control other aspects of how text displays. The value of
3638 the `display' property should be a display specification, as described
3639 below, or a list or vector containing display specifications.
3640
3641 *** Replacing text, displaying text in marginal areas
3642
3643 To replace the text having the `display' property with some other
3644 text, use a display specification of the form `(LOCATION STRING)'.
3645
3646 If LOCATION is `(margin left-margin)', STRING is displayed in the left
3647 marginal area, if it is `(margin right-margin)', it is displayed in
3648 the right marginal area, and if LOCATION is `(margin nil)' STRING
3649 is displayed in the text. In the latter case you can also use the
3650 simpler form STRING as property value.
3651
3652 *** Variable width and height spaces
3653
3654 To display a space of fractional width or height, use a display
3655 specification of the form `(LOCATION STRECH)'. If LOCATION is
3656 `(margin left-margin)', the space is displayed in the left marginal
3657 area, if it is `(margin right-margin)', it is displayed in the right
3658 marginal area, and if LOCATION is `(margin nil)' the space is
3659 displayed in the text. In the latter case you can also use the
3660 simpler form STRETCH as property value.
3661
3662 The stretch specification STRETCH itself is a list of the form `(space
3663 PROPS)', where PROPS is a property list which can contain the
3664 properties described below.
3665
3666 The display of the fractional space replaces the display of the
3667 characters having the `display' property.
3668
3669 - :width WIDTH
3670
3671 Specifies that the space width should be WIDTH times the normal
3672 character width. WIDTH can be an integer or floating point number.
3673
3674 - :relative-width FACTOR
3675
3676 Specifies that the width of the stretch should be computed from the
3677 first character in a group of consecutive characters that have the
3678 same `display' property. The computation is done by multiplying the
3679 width of that character by FACTOR.
3680
3681 - :align-to HPOS
3682
3683 Specifies that the space should be wide enough to reach HPOS. The
3684 value HPOS is measured in units of the normal character width.
3685
3686 Exactly one of the above properties should be used.
3687
3688 - :height HEIGHT
3689
3690 Specifies the height of the space, as HEIGHT, measured in terms of the
3691 normal line height.
3692
3693 - :relative-height FACTOR
3694
3695 The height of the space is computed as the product of the height
3696 of the text having the `display' property and FACTOR.
3697
3698 - :ascent ASCENT
3699
3700 Specifies that ASCENT percent of the height of the stretch should be
3701 used for the ascent of the stretch, i.e. for the part above the
3702 baseline. The value of ASCENT must be a non-negative number less or
3703 equal to 100.
3704
3705 You should not use both `:height' and `:relative-height' together.
3706
3707 *** Images
3708
3709 A display specification for an image has the form `(LOCATION
3710 . IMAGE)', where IMAGE is an image specification. The image replaces,
3711 in the display, the characters having this display specification in
3712 their `display' text property. If LOCATION is `(margin left-margin)',
3713 the image will be displayed in the left marginal area, if it is
3714 `(margin right-margin)' it will be displayed in the right marginal
3715 area, and if LOCATION is `(margin nil)' the image will be displayed in
3716 the text. In the latter case you can also use the simpler form IMAGE
3717 as display specification.
3718
3719 *** Other display properties
3720
3721 - :space-width FACTOR
3722
3723 Specifies that space characters in the text having that property
3724 should be displayed FACTOR times as wide as normal; FACTOR must be an
3725 integer or float.
3726
3727 - :height HEIGHT
3728
3729 Display text having this property in a font that is smaller or larger.
3730
3731 If HEIGHT is a list of the form `(+ N)', where N is an integer, that
3732 means to use a font that is N steps larger. If HEIGHT is a list of
3733 the form `(- N)', that means to use a font that is N steps smaller. A
3734 ``step'' is defined by the set of available fonts; each size for which
3735 a font is available counts as a step.
3736
3737 If HEIGHT is a number, that means to use a font that is HEIGHT times
3738 as tall as the frame's default font.
3739
3740 If HEIGHT is a symbol, it is called as a function with the current
3741 height as argument. The function should return the new height to use.
3742
3743 Otherwise, HEIGHT is evaluated to get the new height, with the symbol
3744 `height' bound to the current specified font height.
3745
3746 - :raise FACTOR
3747
3748 FACTOR must be a number, specifying a multiple of the current
3749 font's height. If it is positive, that means to display the characters
3750 raised. If it is negative, that means to display them lower down. The
3751 amount of raising or lowering is computed without taking account of the
3752 `:height' subproperty.
3753
3754 *** Conditional display properties
3755
3756 All display specifications can be conditionalized. If a specification
3757 has the form `(:when CONDITION . SPEC)', the specification SPEC
3758 applies only when CONDITION yields a non-nil value when evaluated.
3759 During evaluattion, point is temporarily set to the end position of
3760 the text having the `display' property.
3761
3762 The normal specification consisting of SPEC only is equivalent to
3763 `(:when t SPEC)'.
3764
3765 +++
3766 ** New menu separator types.
3767
3768 Emacs now supports more than one menu separator type. Menu items with
3769 item names consisting of dashes only (including zero dashes) are
3770 treated like before. In addition, the following item names are used
3771 to specify other menu separator types.
3772
3773 - `--no-line' or `--space', or `--:space', or `--:noLine'
3774
3775 No separator lines are drawn, but a small space is inserted where the
3776 separator occurs.
3777
3778 - `--single-line' or `--:singleLine'
3779
3780 A single line in the menu's foreground color.
3781
3782 - `--double-line' or `--:doubleLine'
3783
3784 A double line in the menu's foreground color.
3785
3786 - `--single-dashed-line' or `--:singleDashedLine'
3787
3788 A single dashed line in the menu's foreground color.
3789
3790 - `--double-dashed-line' or `--:doubleDashedLine'
3791
3792 A double dashed line in the menu's foreground color.
3793
3794 - `--shadow-etched-in' or `--:shadowEtchedIn'
3795
3796 A single line with 3D sunken appearance. This is the the form
3797 displayed for item names consisting of dashes only.
3798
3799 - `--shadow-etched-out' or `--:shadowEtchedOut'
3800
3801 A single line with 3D raised appearance.
3802
3803 - `--shadow-etched-in-dash' or `--:shadowEtchedInDash'
3804
3805 A single dashed line with 3D sunken appearance.
3806
3807 - `--shadow-etched-out-dash' or `--:shadowEtchedOutDash'
3808
3809 A single dashed line with 3D raise appearance.
3810
3811 - `--shadow-double-etched-in' or `--:shadowDoubleEtchedIn'
3812
3813 Two lines with 3D sunken appearance.
3814
3815 - `--shadow-double-etched-out' or `--:shadowDoubleEtchedOut'
3816
3817 Two lines with 3D raised appearance.
3818
3819 - `--shadow-double-etched-in-dash' or `--:shadowDoubleEtchedInDash'
3820
3821 Two dashed lines with 3D sunken appearance.
3822
3823 - `--shadow-double-etched-out-dash' or `--:shadowDoubleEtchedOutDash'
3824
3825 Two dashed lines with 3D raised appearance.
3826
3827 Under LessTif/Motif, the last four separator types are displayed like
3828 the corresponding single-line separators.
3829
3830 +++
3831 ** New frame parameters for scroll bar colors.
3832
3833 The new frame parameters `scroll-bar-foreground' and
3834 `scroll-bar-background' can be used to change scroll bar colors.
3835 Their value must be either a color name, a string, or nil to specify
3836 that scroll bars should use a default color. For toolkit scroll bars,
3837 default colors are toolkit specific. For non-toolkit scroll bars, the
3838 default background is the background color of the frame, and the
3839 default foreground is black.
3840
3841 The X resource name of these parameters are `scrollBarForeground'
3842 (class ScrollBarForeground) and `scrollBarBackground' (class
3843 `ScrollBarBackground').
3844
3845 Setting these parameters overrides toolkit specific X resource
3846 settings for scroll bar colors.
3847
3848 +++
3849 ** You can set `redisplay-dont-pause' to a non-nil value to prevent
3850 display updates from being interrupted when input is pending.
3851
3852 ---
3853 ** Changing a window's width may now change its window start if it
3854 starts on a continuation line. The new window start is computed based
3855 on the window's new width, starting from the start of the continued
3856 line as the start of the screen line with the minimum distance from
3857 the original window start.
3858
3859 ---
3860 ** The variable `hscroll-step' and the functions
3861 `hscroll-point-visible' and `hscroll-window-column' have been removed
3862 now that proper horizontal scrolling is implemented.
3863
3864 +++
3865 ** Windows can now be made fixed-width and/or fixed-height.
3866
3867 A window is fixed-size if its buffer has a buffer-local variable
3868 `window-size-fixed' whose value is not nil. A value of `height' makes
3869 windows fixed-height, a value of `width' makes them fixed-width, any
3870 other non-nil value makes them both fixed-width and fixed-height.
3871
3872 The following code makes all windows displaying the current buffer
3873 fixed-width and fixed-height.
3874
3875 (set (make-local-variable 'window-size-fixed) t)
3876
3877 A call to enlarge-window on a window gives an error if that window is
3878 fixed-width and it is tried to change the window's width, or if the
3879 window is fixed-height, and it is tried to change its height. To
3880 change the size of a fixed-size window, bind `window-size-fixed'
3881 temporarily to nil, for example
3882
3883 (let ((window-size-fixed nil))
3884 (enlarge-window 10))
3885
3886 Likewise, an attempt to split a fixed-height window vertically,
3887 or a fixed-width window horizontally results in a error.
3888
3889 ** The cursor-type frame parameter is now supported on MS-DOS
3890 terminals. When Emacs starts, it by default changes the cursor shape
3891 to a solid box, as it does on Unix. The `cursor-type' frame parameter
3892 overrides this as it does on Unix, except that the bar cursor is
3893 horizontal rather than vertical (since the MS-DOS display doesn't
3894 support a vertical-bar cursor).
3895
3896
3897 ^L
3898 * Emacs 20.7 is a bug-fix release with few user-visible changes
3899
3900 ** It is now possible to use CCL-based coding systems for keyboard
3901 input.
3902
3903 ** ange-ftp now handles FTP security extensions, like Kerberos.
3904
3905 ** Rmail has been extended to recognize more forms of digest messages.
3906
3907 ** Now, most coding systems set in keyboard coding system work not
3908 only for character input, but also in incremental search. The
3909 exceptions are such coding systems that handle 2-byte character sets
3910 (e.g euc-kr, euc-jp) and that use ISO's escape sequence
3911 (e.g. iso-2022-jp). They are ignored in incremental search.
3912
3913 ** Support for Macintosh PowerPC-based machines running GNU/Linux has
3914 been added.
3915
3916 ^L
3917 * Emacs 20.6 is a bug-fix release with one user-visible change
3918
3919 ** Support for ARM-based non-RISCiX machines has been added.
3920
3921 ^L
3922 * Emacs 20.5 is a bug-fix release with no user-visible changes.
3923
3924 ** Not new, but not mentioned before:
3925 M-w when Transient Mark mode is enabled disables the mark.
3926 \f
3927 * Changes in Emacs 20.4
3928
3929 ** Init file may be called .emacs.el.
3930
3931 You can now call the Emacs init file `.emacs.el'.
3932 Formerly the name had to be `.emacs'. If you use the name
3933 `.emacs.el', you can byte-compile the file in the usual way.
3934
3935 If both `.emacs' and `.emacs.el' exist, the latter file
3936 is the one that is used.
3937
3938 ** shell-command, and shell-command-on-region, now return
3939 the exit code of the command (unless it is asynchronous).
3940 Also, you can specify a place to put the error output,
3941 separate from the command's regular output.
3942 Interactively, the variable shell-command-default-error-buffer
3943 says where to put error output; set it to a buffer name.
3944 In calls from Lisp, an optional argument ERROR-BUFFER specifies
3945 the buffer name.
3946
3947 When you specify a non-nil error buffer (or buffer name), any error
3948 output is inserted before point in that buffer, with \f\n to separate
3949 it from the previous batch of error output. The error buffer is not
3950 cleared, so error output from successive commands accumulates there.
3951
3952 ** Setting the default value of enable-multibyte-characters to nil in
3953 the .emacs file, either explicitly using setq-default, or via Custom,
3954 is now essentially equivalent to using --unibyte: all buffers
3955 created during startup will be made unibyte after loading .emacs.
3956
3957 ** C-x C-f now handles the wildcards * and ? in file names. For
3958 example, typing C-x C-f c*.c RET visits all the files whose names
3959 match c*.c. To visit a file whose name contains * or ?, add the
3960 quoting sequence /: to the beginning of the file name.
3961
3962 ** The M-x commands keep-lines, flush-lines and count-matches
3963 now have the same feature as occur and query-replace:
3964 if the pattern contains any upper case letters, then
3965 they never ignore case.
3966
3967 ** The end-of-line format conversion feature previously mentioned
3968 under `* Emacs 20.1 changes for MS-DOS and MS-Windows' actually
3969 applies to all operating systems. Emacs recognizes from the contents
3970 of a file what convention it uses to separate lines--newline, CRLF, or
3971 just CR--and automatically converts the contents to the normal Emacs
3972 convention (using newline to separate lines) for editing. This is a
3973 part of the general feature of coding system conversion.
3974
3975 If you subsequently save the buffer, Emacs converts the text back to
3976 the same format that was used in the file before.
3977
3978 You can turn off end-of-line conversion by setting the variable
3979 `inhibit-eol-conversion' to non-nil, e.g. with Custom in the MULE group.
3980
3981 ** The character set property `prefered-coding-system' has been
3982 renamed to `preferred-coding-system', for the sake of correct spelling.
3983 This is a fairly internal feature, so few programs should be affected.
3984
3985 ** Mode-line display of end-of-line format is changed.
3986 The indication of the end-of-line format of the file visited by a
3987 buffer is now more explicit when that format is not the usual one for
3988 your operating system. For example, the DOS-style end-of-line format
3989 is displayed as "(DOS)" on Unix and GNU/Linux systems. The usual
3990 end-of-line format is still displayed as a single character (colon for
3991 Unix, backslash for DOS and Windows, and forward slash for the Mac).
3992
3993 The values of the variables eol-mnemonic-unix, eol-mnemonic-dos,
3994 eol-mnemonic-mac, and eol-mnemonic-undecided, which are strings,
3995 control what is displayed in the mode line for each end-of-line
3996 format. You can now customize these variables.
3997
3998 ** In the previous version of Emacs, tar-mode didn't work well if a
3999 filename contained non-ASCII characters. Now this is fixed. Such a
4000 filename is decoded by file-name-coding-system if the default value of
4001 enable-multibyte-characters is non-nil.
4002
4003 ** The command temp-buffer-resize-mode toggles a minor mode
4004 in which temporary buffers (such as help buffers) are given
4005 windows just big enough to hold the whole contents.
4006
4007 ** If you use completion.el, you must now run the function
4008 dynamic-completion-mode to enable it. Just loading the file
4009 doesn't have any effect.
4010
4011 ** In Flyspell mode, the default is now to make just one Ispell process,
4012 not one per buffer.
4013
4014 ** If you use iswitchb but do not call (iswitchb-default-keybindings) to
4015 use the default keybindings, you will need to add the following line:
4016 (add-hook 'minibuffer-setup-hook 'iswitchb-minibuffer-setup)
4017
4018 ** Auto-show mode is no longer enabled just by loading auto-show.el.
4019 To control it, set `auto-show-mode' via Custom or use the
4020 `auto-show-mode' command.
4021
4022 ** Handling of X fonts' ascent/descent parameters has been changed to
4023 avoid redisplay problems. As a consequence, compared with previous
4024 versions the line spacing and frame size now differ with some font
4025 choices, typically increasing by a pixel per line. This change
4026 occurred in version 20.3 but was not documented then.
4027
4028 ** If you select the bar cursor style, it uses the frame's
4029 cursor-color, rather than the cursor foreground pixel.
4030
4031 ** In multibyte mode, Rmail decodes incoming MIME messages using the
4032 character set specified in the message. If you want to disable this
4033 feature, set the variable rmail-decode-mime-charset to nil.
4034
4035 ** Not new, but not mentioned previously in NEWS: when you use #! at
4036 the beginning of a file to make it executable and specify an
4037 interpreter program, Emacs looks on the second line for the -*- mode
4038 and variable specification, as well as on the first line.
4039
4040 ** Support for IBM codepage encoding of non-ASCII characters.
4041
4042 The new command M-x codepage-setup creates a special coding system
4043 that can be used to convert text between a specific IBM codepage and
4044 one of the character sets built into Emacs which matches that
4045 codepage. For example, codepage 850 corresponds to Latin-1 character
4046 set, codepage 855 corresponds to Cyrillic-ISO character set, etc.
4047
4048 Windows codepages 1250, 1251 and some others, where Windows deviates
4049 from the corresponding ISO character set, are also supported.
4050
4051 IBM box-drawing characters and other glyphs which don't have
4052 equivalents in the corresponding ISO character set, are converted to
4053 a character defined by dos-unsupported-char-glyph on MS-DOS, and to
4054 `?' on other systems.
4055
4056 IBM codepages are widely used on MS-DOS and MS-Windows, so this
4057 feature is most useful on those platforms, but it can also be used on
4058 Unix.
4059
4060 Emacs compiled for MS-DOS automatically loads the support for the
4061 current codepage when it starts.
4062
4063 ** Mail changes
4064
4065 *** When mail is sent using compose-mail (C-x m), and if
4066 `mail-send-nonascii' is set to the new default value `mime',
4067 appropriate MIME headers are added. The headers are added only if
4068 non-ASCII characters are present in the body of the mail, and no other
4069 MIME headers are already present. For example, the following three
4070 headers are added if the coding system used in the *mail* buffer is
4071 latin-1:
4072
4073 MIME-version: 1.0
4074 Content-type: text/plain; charset=iso-8859-1
4075 Content-Transfer-Encoding: 8bit
4076
4077 *** The new variable default-sendmail-coding-system specifies the
4078 default way to encode outgoing mail. This has higher priority than
4079 default-buffer-file-coding-system but has lower priority than
4080 sendmail-coding-system and the local value of
4081 buffer-file-coding-system.
4082
4083 You should not set this variable manually. Instead, set
4084 sendmail-coding-system to specify a fixed encoding for all outgoing
4085 mail.
4086
4087 *** When you try to send a message that contains non-ASCII characters,
4088 if the coding system specified by those variables doesn't handle them,
4089 Emacs will ask you to select a suitable coding system while showing a
4090 list of possible coding systems.
4091
4092 ** CC Mode changes
4093
4094 *** c-default-style can now take an association list that maps major
4095 modes to style names. When this variable is an alist, Java mode no
4096 longer hardcodes a setting to "java" style. See the variable's
4097 docstring for details.
4098
4099 *** It's now possible to put a list as the offset on a syntactic
4100 symbol. The list is evaluated recursively until a non-nil offset is
4101 found. This is useful to combine several lineup functions to act in a
4102 prioritized order on a single line. However, none of the supplied
4103 lineup functions use this feature currently.
4104
4105 *** New syntactic symbol catch-clause, which is used on the "catch" and
4106 "finally" lines in try-catch constructs in C++ and Java.
4107
4108 *** New cleanup brace-catch-brace on c-cleanup-list, which does for
4109 "catch" lines what brace-elseif-brace does for "else if" lines.
4110
4111 *** The braces of Java anonymous inner classes are treated separately
4112 from the braces of other classes in auto-newline mode. Two new
4113 symbols inexpr-class-open and inexpr-class-close may be used on
4114 c-hanging-braces-alist to control the automatic newlines used for
4115 anonymous classes.
4116
4117 *** Support for the Pike language added, along with new Pike specific
4118 syntactic symbols: inlambda, lambda-intro-cont
4119
4120 *** Support for Java anonymous classes via new syntactic symbol
4121 inexpr-class. New syntactic symbol inexpr-statement for Pike
4122 support and gcc-style statements inside expressions. New lineup
4123 function c-lineup-inexpr-block.
4124
4125 *** New syntactic symbol brace-entry-open which is used in brace lists
4126 (i.e. static initializers) when a list entry starts with an open
4127 brace. These used to be recognized as brace-list-entry's.
4128 c-electric-brace also recognizes brace-entry-open braces
4129 (brace-list-entry's can no longer be electrified).
4130
4131 *** New command c-indent-line-or-region, not bound by default.
4132
4133 *** `#' is only electric when typed in the indentation of a line.
4134
4135 *** Parentheses are now electric (via the new command c-electric-paren)
4136 for auto-reindenting lines when parens are typed.
4137
4138 *** In "gnu" style, inline-open offset is now set to zero.
4139
4140 *** Uniform handling of the inclass syntactic symbol. The indentation
4141 associated with it is now always relative to the class opening brace.
4142 This means that the indentation behavior has changed in some
4143 circumstances, but only if you've put anything besides 0 on the
4144 class-open syntactic symbol (none of the default styles do that).
4145
4146 ** Gnus changes.
4147
4148 *** New functionality for using Gnus as an offline newsreader has been
4149 added. A plethora of new commands and modes have been added. See the
4150 Gnus manual for the full story.
4151
4152 *** The nndraft backend has returned, but works differently than
4153 before. All Message buffers are now also articles in the nndraft
4154 group, which is created automatically.
4155
4156 *** `gnus-alter-header-function' can now be used to alter header
4157 values.
4158
4159 *** `gnus-summary-goto-article' now accept Message-ID's.
4160
4161 *** A new Message command for deleting text in the body of a message
4162 outside the region: `C-c C-v'.
4163
4164 *** You can now post to component group in nnvirtual groups with
4165 `C-u C-c C-c'.
4166
4167 *** `nntp-rlogin-program' -- new variable to ease customization.
4168
4169 *** `C-u C-c C-c' in `gnus-article-edit-mode' will now inhibit
4170 re-highlighting of the article buffer.
4171
4172 *** New element in `gnus-boring-article-headers' -- `long-to'.
4173
4174 *** `M-i' symbolic prefix command. See the section "Symbolic
4175 Prefixes" in the Gnus manual for details.
4176
4177 *** `L' and `I' in the summary buffer now take the symbolic prefix
4178 `a' to add the score rule to the "all.SCORE" file.
4179
4180 *** `gnus-simplify-subject-functions' variable to allow greater
4181 control over simplification.
4182
4183 *** `A T' -- new command for fetching the current thread.
4184
4185 *** `/ T' -- new command for including the current thread in the
4186 limit.
4187
4188 *** `M-RET' is a new Message command for breaking cited text.
4189
4190 *** \\1-expressions are now valid in `nnmail-split-methods'.
4191
4192 *** The `custom-face-lookup' function has been removed.
4193 If you used this function in your initialization files, you must
4194 rewrite them to use `face-spec-set' instead.
4195
4196 *** Cancelling now uses the current select method. Symbolic prefix
4197 `a' forces normal posting method.
4198
4199 *** New command to translate M******** sm*rtq**t*s into proper text
4200 -- `W d'.
4201
4202 *** For easier debugging of nntp, you can set `nntp-record-commands'
4203 to a non-nil value.
4204
4205 *** nntp now uses ~/.authinfo, a .netrc-like file, for controlling
4206 where and how to send AUTHINFO to NNTP servers.
4207
4208 *** A command for editing group parameters from the summary buffer
4209 has been added.
4210
4211 *** A history of where mails have been split is available.
4212
4213 *** A new article date command has been added -- `article-date-iso8601'.
4214
4215 *** Subjects can be simplified when threading by setting
4216 `gnus-score-thread-simplify'.
4217
4218 *** A new function for citing in Message has been added --
4219 `message-cite-original-without-signature'.
4220
4221 *** `article-strip-all-blank-lines' -- new article command.
4222
4223 *** A new Message command to kill to the end of the article has
4224 been added.
4225
4226 *** A minimum adaptive score can be specified by using the
4227 `gnus-adaptive-word-minimum' variable.
4228
4229 *** The "lapsed date" article header can be kept continually
4230 updated by the `gnus-start-date-timer' command.
4231
4232 *** Web listserv archives can be read with the nnlistserv backend.
4233
4234 *** Old dejanews archives can now be read by nnweb.
4235
4236 *** `gnus-posting-styles' has been re-activated.
4237
4238 ** Changes to TeX and LaTeX mode
4239
4240 *** The new variable `tex-start-options-string' can be used to give
4241 options for the TeX run. The default value causes TeX to run in
4242 nonstopmode. For an interactive TeX run set it to nil or "".
4243
4244 *** The command `tex-feed-input' sends input to the Tex Shell. In a
4245 TeX buffer it is bound to the keys C-RET, C-c RET, and C-c C-m (some
4246 of these keys may not work on all systems). For instance, if you run
4247 TeX interactively and if the TeX run stops because of an error, you
4248 can continue it without leaving the TeX buffer by typing C-RET.
4249
4250 *** The Tex Shell Buffer is now in `compilation-shell-minor-mode'.
4251 All error-parsing commands of the Compilation major mode are available
4252 but bound to keys that don't collide with the shell. Thus you can use
4253 the Tex Shell for command line executions like a usual shell.
4254
4255 *** The commands `tex-validate-region' and `tex-validate-buffer' check
4256 the matching of braces and $'s. The errors are listed in a *Occur*
4257 buffer and you can use C-c C-c or mouse-2 to go to a particular
4258 mismatch.
4259
4260 ** Changes to RefTeX mode
4261
4262 *** The table of contents buffer can now also display labels and
4263 file boundaries in addition to sections. Use `l', `i', and `c' keys.
4264
4265 *** Labels derived from context (the section heading) are now
4266 lowercase by default. To make the label legal in LaTeX, latin-1
4267 characters will lose their accent. All Mule characters will be
4268 removed from the label.
4269
4270 *** The automatic display of cross reference information can also use
4271 a window instead of the echo area. See variable `reftex-auto-view-crossref'.
4272
4273 *** kpsewhich can be used by RefTeX to find TeX and BibTeX files. See the
4274 customization group `reftex-finding-files'.
4275
4276 *** The option `reftex-bibfile-ignore-list' has been renamed to
4277 `reftex-bibfile-ignore-regexps' and indeed can be fed with regular
4278 expressions.
4279
4280 *** Multiple Selection buffers are now hidden buffers.
4281
4282 ** New/deleted modes and packages
4283
4284 *** The package snmp-mode.el provides major modes for editing SNMP and
4285 SNMPv2 MIBs. It has entries on `auto-mode-alist'.
4286
4287 *** The package sql.el provides a major mode, M-x sql-mode, for
4288 editing SQL files, and M-x sql-interactive-mode for interacting with
4289 SQL interpreters. It has an entry on `auto-mode-alist'.
4290
4291 *** M-x highlight-changes-mode provides a minor mode displaying buffer
4292 changes with a special face.
4293
4294 *** ispell4.el has been deleted. It got in the way of ispell.el and
4295 this was hard to fix reliably. It has long been obsolete -- use
4296 Ispell 3.1 and ispell.el.
4297 \f
4298 * MS-DOS changes in Emacs 20.4
4299
4300 ** Emacs compiled for MS-DOS now supports MULE features better.
4301 This includes support for display of all ISO 8859-N character sets,
4302 conversion to and from IBM codepage encoding of non-ASCII characters,
4303 and automatic setup of the MULE environment at startup. For details,
4304 check out the section `MS-DOS and MULE' in the manual.
4305
4306 The MS-DOS installation procedure automatically configures and builds
4307 Emacs with input method support if it finds an unpacked Leim
4308 distribution when the config.bat script is run.
4309
4310 ** Formerly, the value of lpr-command did not affect printing on
4311 MS-DOS unless print-region-function was set to nil, but now it
4312 controls whether an external program is invoked or output is written
4313 directly to a printer port. Similarly, in the previous version of
4314 Emacs, the value of ps-lpr-command did not affect PostScript printing
4315 on MS-DOS unless ps-printer-name was set to something other than a
4316 string (eg. t or `pipe'), but now it controls whether an external
4317 program is used. (These changes were made so that configuration of
4318 printing variables would be almost identical across all platforms.)
4319
4320 ** In the previous version of Emacs, PostScript and non-PostScript
4321 output was piped to external programs, but because most print programs
4322 available for MS-DOS and MS-Windows cannot read data from their standard
4323 input, on those systems the data to be output is now written to a
4324 temporary file whose name is passed as the last argument to the external
4325 program.
4326
4327 An exception is made for `print', a standard program on Windows NT,
4328 and `nprint', a standard program on Novell Netware. For both of these
4329 programs, the command line is constructed in the appropriate syntax
4330 automatically, using only the value of printer-name or ps-printer-name
4331 as appropriate--the value of the relevant `-switches' variable is
4332 ignored, as both programs have no useful switches.
4333
4334 ** The value of the variable dos-printer (cf. dos-ps-printer), if it has
4335 a value, overrides the value of printer-name (cf. ps-printer-name), on
4336 MS-DOS and MS-Windows only. This has been true since version 20.3, but
4337 was not documented clearly before.
4338
4339 ** All the Emacs games now work on MS-DOS terminals.
4340 This includes Tetris and Snake.
4341 \f
4342 * Lisp changes in Emacs 20.4
4343
4344 ** New functions line-beginning-position and line-end-position
4345 return the position of the beginning or end of the current line.
4346 They both accept an optional argument, which has the same
4347 meaning as the argument to beginning-of-line or end-of-line.
4348
4349 ** find-file and allied functions now have an optional argument
4350 WILDCARD. If this is non-nil, they do wildcard processing,
4351 and visit all files that match the wildcard pattern.
4352
4353 ** Changes in the file-attributes function.
4354
4355 *** The file size returned by file-attributes may be an integer or a float.
4356 It is an integer if the size fits in a Lisp integer, float otherwise.
4357
4358 *** The inode number returned by file-attributes may be an integer (if
4359 the number fits in a Lisp integer) or a cons cell containing two
4360 integers.
4361
4362 ** The new function directory-files-and-attributes returns a list of
4363 files in a directory and their attributes. It accepts the same
4364 arguments as directory-files and has similar semantics, except that
4365 file names and attributes are returned.
4366
4367 ** The new function file-attributes-lessp is a helper function for
4368 sorting the list generated by directory-files-and-attributes. It
4369 accepts two arguments, each a list of a file name and its atttributes.
4370 It compares the file names of each according to string-lessp and
4371 returns the result.
4372
4373 ** The new function file-expand-wildcards expands a wildcard-pattern
4374 to produce a list of existing files that match the pattern.
4375
4376 ** New functions for base64 conversion:
4377
4378 The function base64-encode-region converts a part of the buffer
4379 into the base64 code used in MIME. base64-decode-region
4380 performs the opposite conversion. Line-breaking is supported
4381 optionally.
4382
4383 Functions base64-encode-string and base64-decode-string do a similar
4384 job on the text in a string. They return the value as a new string.
4385
4386 **
4387 The new function process-running-child-p
4388 will tell you if a subprocess has given control of its
4389 terminal to its own child process.
4390
4391 ** interrupt-process and such functions have a new feature:
4392 when the second argument is `lambda', they send a signal
4393 to the running child of the subshell, if any, but if the shell
4394 itself owns its terminal, no signal is sent.
4395
4396 ** There are new widget types `plist' and `alist' which can
4397 be used for customizing variables whose values are plists or alists.
4398
4399 ** easymenu.el Now understands `:key-sequence' and `:style button'.
4400 :included is an alias for :visible.
4401
4402 easy-menu-add-item now understands the values returned by
4403 easy-menu-remove-item and easy-menu-item-present-p. This can be used
4404 to move or copy menu entries.
4405
4406 ** Multibyte editing changes
4407
4408 *** The definitions of sref and char-bytes are changed. Now, sref is
4409 an alias of aref and char-bytes always returns 1. This change is to
4410 make some Emacs Lisp code which works on 20.2 and earlier also
4411 work on the latest Emacs. Such code uses a combination of sref and
4412 char-bytes in a loop typically as below:
4413 (setq char (sref str idx)
4414 idx (+ idx (char-bytes idx)))
4415 The byte-compiler now warns that this is obsolete.
4416
4417 If you want to know how many bytes a specific multibyte character
4418 (say, CH) occupies in a multibyte buffer, use this code:
4419 (charset-bytes (char-charset ch))
4420
4421 *** In multibyte mode, when you narrow a buffer to some region, and the
4422 region is preceded or followed by non-ASCII codes, inserting or
4423 deleting at the head or the end of the region may signal this error:
4424
4425 Byte combining across boundary of accessible buffer text inhibitted
4426
4427 This is to avoid some bytes being combined together into a character
4428 across the boundary.
4429
4430 *** The functions find-charset-region and find-charset-string include
4431 `unknown' in the returned list in the following cases:
4432 o The current buffer or the target string is unibyte and
4433 contains 8-bit characters.
4434 o The current buffer or the target string is multibyte and
4435 contains invalid characters.
4436
4437 *** The functions decode-coding-region and encode-coding-region remove
4438 text properties of the target region. Ideally, they should correctly
4439 preserve text properties, but for the moment, it's hard. Removing
4440 text properties is better than preserving them in a less-than-correct
4441 way.
4442
4443 *** prefer-coding-system sets EOL conversion of default coding systems.
4444 If the argument to prefer-coding-system specifies a certain type of
4445 end of line conversion, the default coding systems set by
4446 prefer-coding-system will specify that conversion type for end of line.
4447
4448 *** The new function thai-compose-string can be used to properly
4449 compose Thai characters in a string.
4450
4451 ** The primitive `define-prefix-command' now takes an optional third
4452 argument NAME, which should be a string. It supplies the menu name
4453 for the created keymap. Keymaps created in order to be displayed as
4454 menus should always use the third argument.
4455
4456 ** The meanings of optional second arguments for read-char,
4457 read-event, and read-char-exclusive are flipped. Now the second
4458 arguments are INHERIT-INPUT-METHOD. These functions use the current
4459 input method (if any) if and only if INHERIT-INPUT-METHOD is non-nil.
4460
4461 ** The new function clear-this-command-keys empties out the contents
4462 of the vector that (this-command-keys) returns. This is useful in
4463 programs that read passwords, to prevent the passwords from echoing
4464 inadvertently as part of the next command in certain cases.
4465
4466 ** The new macro `with-temp-message' displays a temporary message in
4467 the echo area, while executing some Lisp code. Like `progn', it
4468 returns the value of the last form, but it also restores the previous
4469 echo area contents.
4470
4471 (with-temp-message MESSAGE &rest BODY)
4472
4473 ** The function `require' now takes an optional third argument
4474 NOERROR. If it is non-nil, then there is no error if the
4475 requested feature cannot be loaded.
4476
4477 ** In the function modify-face, an argument of (nil) for the
4478 foreground color, background color or stipple pattern
4479 means to clear out that attribute.
4480
4481 ** The `outer-window-id' frame property of an X frame
4482 gives the window number of the outermost X window for the frame.
4483
4484 ** Temporary buffers made with with-output-to-temp-buffer are now
4485 read-only by default, and normally use the major mode Help mode
4486 unless you put them in some other non-Fundamental mode before the
4487 end of with-output-to-temp-buffer.
4488
4489 ** The new functions gap-position and gap-size return information on
4490 the gap of the current buffer.
4491
4492 ** The new functions position-bytes and byte-to-position provide a way
4493 to convert between character positions and byte positions in the
4494 current buffer.
4495
4496 ** vc.el defines two new macros, `edit-vc-file' and `with-vc-file', to
4497 facilitate working with version-controlled files from Lisp programs.
4498 These macros check out a given file automatically if needed, and check
4499 it back in after any modifications have been made.
4500 \f
4501 * Installation Changes in Emacs 20.3
4502
4503 ** The default value of load-path now includes most subdirectories of
4504 the site-specific directories /usr/local/share/emacs/site-lisp and
4505 /usr/local/share/emacs/VERSION/site-lisp, in addition to those
4506 directories themselves. Both immediate subdirectories and
4507 subdirectories multiple levels down are added to load-path.
4508
4509 Not all subdirectories are included, though. Subdirectories whose
4510 names do not start with a letter or digit are excluded.
4511 Subdirectories named RCS or CVS are excluded. Also, a subdirectory
4512 which contains a file named `.nosearch' is excluded. You can use
4513 these methods to prevent certain subdirectories from being searched.
4514
4515 Emacs finds these subdirectories and adds them to load-path when it
4516 starts up. While it would be cleaner to find the subdirectories each
4517 time Emacs loads a file, that would be much slower.
4518
4519 This feature is an incompatible change. If you have stored some Emacs
4520 Lisp files in a subdirectory of the site-lisp directory specifically
4521 to prevent them from being used, you will need to rename the
4522 subdirectory to start with a non-alphanumeric character, or create a
4523 `.nosearch' file in it, in order to continue to achieve the desired
4524 results.
4525
4526 ** Emacs no longer includes an old version of the C preprocessor from
4527 GCC. This was formerly used to help compile Emacs with C compilers
4528 that had limits on the significant length of an identifier, but in
4529 fact we stopped supporting such compilers some time ago.
4530 \f
4531 * Changes in Emacs 20.3
4532
4533 ** The new command C-x z (repeat) repeats the previous command
4534 including its argument. If you repeat the z afterward,
4535 it repeats the command additional times; thus, you can
4536 perform many repetitions with one keystroke per repetition.
4537
4538 ** Emacs now supports "selective undo" which undoes only within a
4539 specified region. To do this, set point and mark around the desired
4540 region and type C-u C-x u (or C-u C-_). You can then continue undoing
4541 further, within the same region, by repeating the ordinary undo
4542 command C-x u or C-_. This will keep undoing changes that were made
4543 within the region you originally specified, until either all of them
4544 are undone, or it encounters a change which crosses the edge of that
4545 region.
4546
4547 In Transient Mark mode, undoing when a region is active requests
4548 selective undo.
4549
4550 ** If you specify --unibyte when starting Emacs, then all buffers are
4551 unibyte, except when a Lisp program specifically creates a multibyte
4552 buffer. Setting the environment variable EMACS_UNIBYTE has the same
4553 effect. The --no-unibyte option overrides EMACS_UNIBYTE and directs
4554 Emacs to run normally in multibyte mode.
4555
4556 The option --unibyte does not affect the reading of Emacs Lisp files,
4557 though. If you want a Lisp file to be read in unibyte mode, use
4558 -*-unibyte: t;-*- on its first line. That will force Emacs to
4559 load that file in unibyte mode, regardless of how Emacs was started.
4560
4561 ** toggle-enable-multibyte-characters no longer has a key binding and
4562 no longer appears in the menu bar. We've realized that changing the
4563 enable-multibyte-characters variable in an existing buffer is
4564 something that most users not do.
4565
4566 ** You can specify a coding system to use for the next cut or paste
4567 operations through the window system with the command C-x RET X.
4568 The coding system can make a difference for communication with other
4569 applications.
4570
4571 C-x RET x specifies a coding system for all subsequent cutting and
4572 pasting operations.
4573
4574 ** You can specify the printer to use for commands that do printing by
4575 setting the variable `printer-name'. Just what a printer name looks
4576 like depends on your operating system. You can specify a different
4577 printer for the Postscript printing commands by setting
4578 `ps-printer-name'.
4579
4580 ** Emacs now supports on-the-fly spell checking by the means of a
4581 minor mode. It is called M-x flyspell-mode. You don't have to remember
4582 any other special commands to use it, and you will hardly notice it
4583 except when you make a spelling error. Flyspell works by highlighting
4584 incorrect words as soon as they are completed or as soon as the cursor
4585 hits a new word.
4586
4587 Flyspell mode works with whichever dictionary you have selected for
4588 Ispell in Emacs. In TeX mode, it understands TeX syntax so as not
4589 to be confused by TeX commands.
4590
4591 You can correct a misspelled word by editing it into something
4592 correct. You can also correct it, or accept it as correct, by
4593 clicking on the word with Mouse-2; that gives you a pop-up menu
4594 of various alternative replacements and actions.
4595
4596 Flyspell mode also proposes "automatic" corrections. M-TAB replaces
4597 the current misspelled word with a possible correction. If several
4598 corrections are made possible, M-TAB cycles through them in
4599 alphabetical order, or in order of decreasing likelihood if
4600 flyspell-sort-corrections is nil.
4601
4602 Flyspell mode also flags an error when a word is repeated, if
4603 flyspell-mark-duplications-flag is non-nil.
4604
4605 ** Changes in input method usage.
4606
4607 Now you can use arrow keys (right, left, down, up) for selecting among
4608 the alternatives just the same way as you do by C-f, C-b, C-n, and C-p
4609 respectively.
4610
4611 You can use the ENTER key to accept the current conversion.
4612
4613 If you type TAB to display a list of alternatives, you can select one
4614 of the alternatives with Mouse-2.
4615
4616 The meaning of the variable `input-method-verbose-flag' is changed so
4617 that you can set it to t, nil, `default', or `complex-only'.
4618
4619 If the value is nil, extra guidance is never given.
4620
4621 If the value is t, extra guidance is always given.
4622
4623 If the value is `complex-only', extra guidance is always given only
4624 when you are using complex input methods such as chinese-py.
4625
4626 If the value is `default' (this is the default), extra guidance is
4627 given in the following case:
4628 o When you are using a complex input method.
4629 o When you are using a simple input method but not in the minibuffer.
4630
4631 If you are using Emacs through a very slow line, setting
4632 input-method-verbose-flag to nil or to complex-only is a good choice,
4633 and if you are using an input method you are not familiar with,
4634 setting it to t is helpful.
4635
4636 The old command select-input-method is now called set-input-method.
4637
4638 In the language environment "Korean", you can use the following
4639 keys:
4640 Shift-SPC toggle-korean-input-method
4641 C-F9 quail-hangul-switch-symbol-ksc
4642 F9 quail-hangul-switch-hanja
4643 These key bindings are canceled when you switch to another language
4644 environment.
4645
4646 ** The minibuffer history of file names now records the specified file
4647 names, not the entire minibuffer input. For example, if the
4648 minibuffer starts out with /usr/foo/, you might type in /etc/passwd to
4649 get
4650
4651 /usr/foo//etc/passwd
4652
4653 which stands for the file /etc/passwd.
4654
4655 Formerly, this used to put /usr/foo//etc/passwd in the history list.
4656 Now this puts just /etc/passwd in the history list.
4657
4658 ** If you are root, Emacs sets backup-by-copying-when-mismatch to t
4659 at startup, so that saving a file will be sure to preserve
4660 its owner and group.
4661
4662 ** find-func.el can now also find the place of definition of Emacs
4663 Lisp variables in user-loaded libraries.
4664
4665 ** C-x r t (string-rectangle) now deletes the existing rectangle
4666 contents before inserting the specified string on each line.
4667
4668 ** There is a new command delete-whitespace-rectangle
4669 which deletes whitespace starting from a particular column
4670 in all the lines on a rectangle. The column is specified
4671 by the left edge of the rectangle.
4672
4673 ** You can now store a number into a register with C-u NUMBER C-x r n REG,
4674 increment it by INC with C-u INC C-x r + REG (to increment by one, omit
4675 C-u INC), and insert it in the buffer with C-x r g REG. This is useful
4676 for writing keyboard macros.
4677
4678 ** The new command M-x speedbar displays a frame in which directories,
4679 files, and tags can be displayed, manipulated, and jumped to. The
4680 frame defaults to 20 characters in width, and is the same height as
4681 the frame that it was started from. Some major modes define
4682 additional commands for the speedbar, including Rmail, GUD/GDB, and
4683 info.
4684
4685 ** query-replace-regexp is now bound to C-M-%.
4686
4687 ** In Transient Mark mode, when the region is active, M-x
4688 query-replace and the other replace commands now operate on the region
4689 contents only.
4690
4691 ** M-x write-region, when used interactively, now asks for
4692 confirmation before overwriting an existing file. When you call
4693 the function from a Lisp program, a new optional argument CONFIRM
4694 says whether to ask for confirmation in this case.
4695
4696 ** If you use find-file-literally and the file is already visited
4697 non-literally, the command asks you whether to revisit the file
4698 literally. If you say no, it signals an error.
4699
4700 ** Major modes defined with the "derived mode" feature
4701 now use the proper name for the mode hook: WHATEVER-mode-hook.
4702 Formerly they used the name WHATEVER-mode-hooks, but that is
4703 inconsistent with Emacs conventions.
4704
4705 ** shell-command-on-region (and shell-command) reports success or
4706 failure if the command produces no output.
4707
4708 ** Set focus-follows-mouse to nil if your window system or window
4709 manager does not transfer focus to another window when you just move
4710 the mouse.
4711
4712 ** mouse-menu-buffer-maxlen has been renamed to
4713 mouse-buffer-menu-maxlen to be consistent with the other related
4714 function and variable names.
4715
4716 ** The new variable auto-coding-alist specifies coding systems for
4717 reading specific files. This has higher priority than
4718 file-coding-system-alist.
4719
4720 ** If you set the variable unibyte-display-via-language-environment to
4721 t, then Emacs displays non-ASCII characters are displayed by
4722 converting them to the equivalent multibyte characters according to
4723 the current language environment. As a result, they are displayed
4724 according to the current fontset.
4725
4726 ** C-q's handling of codes in the range 0200 through 0377 is changed.
4727
4728 The codes in the range 0200 through 0237 are inserted as one byte of
4729 that code regardless of the values of nonascii-translation-table and
4730 nonascii-insert-offset.
4731
4732 For the codes in the range 0240 through 0377, if
4733 enable-multibyte-characters is non-nil and nonascii-translation-table
4734 nor nonascii-insert-offset can't convert them to valid multibyte
4735 characters, they are converted to Latin-1 characters.
4736
4737 ** If you try to find a file that is not read-accessible, you now get
4738 an error, rather than an empty buffer and a warning.
4739
4740 ** In the minibuffer history commands M-r and M-s, an upper case
4741 letter in the regular expression forces case-sensitive search.
4742
4743 ** In the *Help* buffer, cross-references to commands and variables
4744 are inferred and hyperlinked. Use C-h m in Help mode for the relevant
4745 command keys.
4746
4747 ** M-x apropos-command, with a prefix argument, no longer looks for
4748 user option variables--instead it looks for noninteractive functions.
4749
4750 Meanwhile, the command apropos-variable normally searches for
4751 user option variables; with a prefix argument, it looks at
4752 all variables that have documentation.
4753
4754 ** When you type a long line in the minibuffer, and the minibuffer
4755 shows just one line, automatically scrolling works in a special way
4756 that shows you overlap with the previous line of text. The variable
4757 minibuffer-scroll-overlap controls how many characters of overlap
4758 it should show; the default is 20.
4759
4760 Meanwhile, Resize Minibuffer mode is still available; in that mode,
4761 the minibuffer grows taller (up to a point) as needed to show the whole
4762 of your input.
4763
4764 ** The new command M-x customize-changed-options lets you customize
4765 all the options whose meanings or default values have changed in
4766 recent Emacs versions. You specify a previous Emacs version number as
4767 argument, and the command creates a customization buffer showing all
4768 the customizable options which were changed since that version.
4769 Newly added options are included as well.
4770
4771 If you don't specify a particular version number argument,
4772 then the customization buffer shows all the customizable options
4773 for which Emacs versions of changes are recorded.
4774
4775 This function is also bound to the Changed Options entry in the
4776 Customize menu.
4777
4778 ** When you run M-x grep with a prefix argument, it figures out
4779 the tag around point and puts that into the default grep command.
4780
4781 ** The new command M-* (pop-tag-mark) pops back through a history of
4782 buffer positions from which M-. or other tag-finding commands were
4783 invoked.
4784
4785 ** The new variable comment-padding specifies the number of spaces
4786 that `comment-region' will insert before the actual text of the comment.
4787 The default is 1.
4788
4789 ** In Fortran mode the characters `.', `_' and `$' now have symbol
4790 syntax, not word syntax. Fortran mode now supports `imenu' and has
4791 new commands fortran-join-line (M-^) and fortran-narrow-to-subprogram
4792 (C-x n d). M-q can be used to fill a statement or comment block
4793 sensibly.
4794
4795 ** GUD now supports jdb, the Java debugger, and pdb, the Python debugger.
4796
4797 ** If you set the variable add-log-keep-changes-together to a non-nil
4798 value, the command `C-x 4 a' will automatically notice when you make
4799 two entries in one day for one file, and combine them.
4800
4801 ** You can use the command M-x diary-mail-entries to mail yourself a
4802 reminder about upcoming diary entries. See the documentation string
4803 for a sample shell script for calling this function automatically
4804 every night.
4805
4806 ** Desktop changes
4807
4808 *** All you need to do to enable use of the Desktop package, is to set
4809 the variable desktop-enable to t with Custom.
4810
4811 *** Minor modes are now restored. Which minor modes are restored
4812 and how modes are restored is controlled by `desktop-minor-mode-table'.
4813
4814 ** There is no need to do anything special, now, to enable Gnus to
4815 read and post multi-lingual articles.
4816
4817 ** Outline mode has now support for showing hidden outlines when
4818 doing an isearch. In order for this to happen search-invisible should
4819 be set to open (the default). If an isearch match is inside a hidden
4820 outline the outline is made visible. If you continue pressing C-s and
4821 the match moves outside the formerly invisible outline, the outline is
4822 made invisible again.
4823
4824 ** Mail reading and sending changes
4825
4826 *** The Rmail e command now switches to displaying the whole header of
4827 the message before it lets you edit the message. This is so that any
4828 changes you make in the header will not be lost if you subsequently
4829 toggle.
4830
4831 *** The w command in Rmail, which writes the message body into a file,
4832 now works in the summary buffer as well. (The command to delete the
4833 summary buffer is now Q.) The default file name for the w command, if
4834 the message has no subject, is stored in the variable
4835 rmail-default-body-file.
4836
4837 *** Most of the commands and modes that operate on mail and netnews no
4838 longer depend on the value of mail-header-separator. Instead, they
4839 handle whatever separator the buffer happens to use.
4840
4841 *** If you set mail-signature to a value which is not t, nil, or a string,
4842 it should be an expression. When you send a message, this expression
4843 is evaluated to insert the signature.
4844
4845 *** The new Lisp library feedmail.el (version 8) enhances processing of
4846 outbound email messages. It works in coordination with other email
4847 handling packages (e.g., rmail, VM, gnus) and is responsible for
4848 putting final touches on messages and actually submitting them for
4849 transmission. Users of the emacs program "fakemail" might be
4850 especially interested in trying feedmail.
4851
4852 feedmail is not enabled by default. See comments at the top of
4853 feedmail.el for set-up instructions. Among the bigger features
4854 provided by feedmail are:
4855
4856 **** you can park outgoing messages into a disk-based queue and
4857 stimulate sending some or all of them later (handy for laptop users);
4858 there is also a queue for draft messages
4859
4860 **** you can get one last look at the prepped outbound message and
4861 be prompted for confirmation
4862
4863 **** does smart filling of address headers
4864
4865 **** can generate a MESSAGE-ID: line and a DATE: line; the date can be
4866 the time the message was written or the time it is being sent; this
4867 can make FCC copies more closely resemble copies that recipients get
4868
4869 **** you can specify an arbitrary function for actually transmitting
4870 the message; included in feedmail are interfaces for /bin/[r]mail,
4871 /usr/lib/sendmail, and elisp smtpmail; it's easy to write a new
4872 function for something else (10-20 lines of elisp)
4873
4874 ** Dired changes
4875
4876 *** The Dired function dired-do-toggle, which toggles marked and unmarked
4877 files, is now bound to "t" instead of "T".
4878
4879 *** dired-at-point has been added to ffap.el. It allows one to easily
4880 run Dired on the directory name at point.
4881
4882 *** Dired has a new command: %g. It searches the contents of
4883 files in the directory and marks each file that contains a match
4884 for a specified regexp.
4885
4886 ** VC Changes
4887
4888 *** New option vc-ignore-vc-files lets you turn off version control
4889 conveniently.
4890
4891 *** VC Dired has been completely rewritten. It is now much
4892 faster, especially for CVS, and works very similar to ordinary
4893 Dired.
4894
4895 VC Dired is invoked by typing C-x v d and entering the name of the
4896 directory to display. By default, VC Dired gives you a recursive
4897 listing of all files at or below the given directory which are
4898 currently locked (for CVS, all files not up-to-date are shown).
4899
4900 You can change the listing format by setting vc-dired-recurse to nil,
4901 then it shows only the given directory, and you may also set
4902 vc-dired-terse-display to nil, then it shows all files under version
4903 control plus the names of any subdirectories, so that you can type `i'
4904 on such lines to insert them manually, as in ordinary Dired.
4905
4906 All Dired commands operate normally in VC Dired, except for `v', which
4907 is redefined as the version control prefix. That means you may type
4908 `v l', `v =' etc. to invoke `vc-print-log', `vc-diff' and the like on
4909 the file named in the current Dired buffer line. `v v' invokes
4910 `vc-next-action' on this file, or on all files currently marked.
4911
4912 The new command `v t' (vc-dired-toggle-terse-mode) allows you to
4913 toggle between terse display (only locked files) and full display (all
4914 VC files plus subdirectories). There is also a special command,
4915 `* l', to mark all files currently locked.
4916
4917 Giving a prefix argument to C-x v d now does the same thing as in
4918 ordinary Dired: it allows you to supply additional options for the ls
4919 command in the minibuffer, to fine-tune VC Dired's output.
4920
4921 *** Under CVS, if you merge changes from the repository into a working
4922 file, and CVS detects conflicts, VC now offers to start an ediff
4923 session to resolve them.
4924
4925 Alternatively, you can use the new command `vc-resolve-conflicts' to
4926 resolve conflicts in a file at any time. It works in any buffer that
4927 contains conflict markers as generated by rcsmerge (which is what CVS
4928 uses as well).
4929
4930 *** You can now transfer changes between branches, using the new
4931 command vc-merge (C-x v m). It is implemented for RCS and CVS. When
4932 you invoke it in a buffer under version-control, you can specify
4933 either an entire branch or a pair of versions, and the changes on that
4934 branch or between the two versions are merged into the working file.
4935 If this results in any conflicts, they may be resolved interactively,
4936 using ediff.
4937
4938 ** Changes in Font Lock
4939
4940 *** The face and variable previously known as font-lock-reference-face
4941 are now called font-lock-constant-face to better reflect their typical
4942 use for highlighting constants and labels. (Its face properties are
4943 unchanged.) The variable font-lock-reference-face remains for now for
4944 compatibility reasons, but its value is font-lock-constant-face.
4945
4946 ** Frame name display changes
4947
4948 *** The command set-frame-name lets you set the name of the current
4949 frame. You can use the new command select-frame-by-name to select and
4950 raise a frame; this is mostly useful on character-only terminals, or
4951 when many frames are invisible or iconified.
4952
4953 *** On character-only terminal (not a window system), changing the
4954 frame name is now reflected on the mode line and in the Buffers/Frames
4955 menu.
4956
4957 ** Comint (subshell) changes
4958
4959 *** In Comint modes, the commands to kill, stop or interrupt a
4960 subjob now also kill pending input. This is for compatibility
4961 with ordinary shells, where the signal characters do this.
4962
4963 *** There are new commands in Comint mode.
4964
4965 C-c C-x fetches the "next" line from the input history;
4966 that is, the line after the last line you got.
4967 You can use this command to fetch successive lines, one by one.
4968
4969 C-c SPC accumulates lines of input. More precisely, it arranges to
4970 send the current line together with the following line, when you send
4971 the following line.
4972
4973 C-c C-a if repeated twice consecutively now moves to the process mark,
4974 which separates the pending input from the subprocess output and the
4975 previously sent input.
4976
4977 C-c M-r now runs comint-previous-matching-input-from-input;
4978 it searches for a previous command, using the current pending input
4979 as the search string.
4980
4981 *** New option compilation-scroll-output can be set to scroll
4982 automatically in compilation-mode windows.
4983
4984 ** C mode changes
4985
4986 *** Multiline macros are now handled, both as they affect indentation,
4987 and as recognized syntax. New syntactic symbol cpp-macro-cont is
4988 assigned to second and subsequent lines of a multiline macro
4989 definition.
4990
4991 *** A new style "user" which captures all non-hook-ified
4992 (i.e. top-level) .emacs file variable settings and customizations.
4993 Style "cc-mode" is an alias for "user" and is deprecated. "gnu"
4994 style is still the default however.
4995
4996 *** "java" style now conforms to Sun's JDK coding style.
4997
4998 *** There are new commands c-beginning-of-defun, c-end-of-defun which
4999 are alternatives which you could bind to C-M-a and C-M-e if you prefer
5000 them. They do not have key bindings by default.
5001
5002 *** New and improved implementations of M-a (c-beginning-of-statement)
5003 and M-e (c-end-of-statement).
5004
5005 *** C++ namespace blocks are supported, with new syntactic symbols
5006 namespace-open, namespace-close, and innamespace.
5007
5008 *** File local variable settings of c-file-style and c-file-offsets
5009 makes the style variables local to that buffer only.
5010
5011 *** New indentation functions c-lineup-close-paren,
5012 c-indent-one-line-block, c-lineup-dont-change.
5013
5014 *** Improvements (hopefully!) to the way CC Mode is loaded. You
5015 should now be able to do a (require 'cc-mode) to get the entire
5016 package loaded properly for customization in your .emacs file. A new
5017 variable c-initialize-on-load controls this and is t by default.
5018
5019 ** Changes to hippie-expand.
5020
5021 *** New customization variable `hippie-expand-dabbrev-skip-space'. If
5022 non-nil, trailing spaces may be included in the abbreviation to search for,
5023 which then gives the same behavior as the original `dabbrev-expand'.
5024
5025 *** New customization variable `hippie-expand-dabbrev-as-symbol'. If
5026 non-nil, characters of syntax '_' is considered part of the word when
5027 expanding dynamically.
5028
5029 *** New customization variable `hippie-expand-no-restriction'. If
5030 non-nil, narrowed buffers are widened before they are searched.
5031
5032 *** New customization variable `hippie-expand-only-buffers'. If
5033 non-empty, buffers searched are restricted to the types specified in
5034 this list. Useful for example when constructing new special-purpose
5035 expansion functions with `make-hippie-expand-function'.
5036
5037 *** Text properties of the expansion are no longer copied.
5038
5039 ** Changes in BibTeX mode.
5040
5041 *** Any titleword matching a regexp in the new variable
5042 bibtex-autokey-titleword-ignore (case sensitive) is ignored during
5043 automatic key generation. This replaces variable
5044 bibtex-autokey-titleword-first-ignore, which only checked for matches
5045 against the first word in the title.
5046
5047 *** Autokey generation now uses all words from the title, not just
5048 capitalized words. To avoid conflicts with existing customizations,
5049 bibtex-autokey-titleword-ignore is set up such that words starting with
5050 lowerkey characters will still be ignored. Thus, if you want to use
5051 lowercase words from the title, you will have to overwrite the
5052 bibtex-autokey-titleword-ignore standard setting.
5053
5054 *** Case conversion of names and title words for automatic key
5055 generation is more flexible. Variable bibtex-autokey-preserve-case is
5056 replaced by bibtex-autokey-titleword-case-convert and
5057 bibtex-autokey-name-case-convert.
5058
5059 ** Changes in vcursor.el.
5060
5061 *** Support for character terminals is available: there is a new keymap
5062 and the vcursor will appear as an arrow between buffer text. A
5063 variable `vcursor-interpret-input' allows input from the vcursor to be
5064 entered exactly as if typed. Numerous functions, including
5065 `vcursor-compare-windows', have been rewritten to improve consistency
5066 in the selection of windows and corresponding keymaps.
5067
5068 *** vcursor options can now be altered with M-x customize under the
5069 Editing group once the package is loaded.
5070
5071 *** Loading vcursor now does not define keys by default, as this is
5072 generally a bad side effect. Use M-x customize to set
5073 vcursor-key-bindings to t to restore the old behaviour.
5074
5075 *** vcursor-auto-disable can be `copy', which turns off copying from the
5076 vcursor, but doesn't disable it, after any non-vcursor command.
5077
5078 ** Ispell changes.
5079
5080 *** You can now spell check comments and strings in the current
5081 buffer with M-x ispell-comments-and-strings. Comments and strings
5082 are identified by syntax tables in effect.
5083
5084 *** Generic region skipping implemented.
5085 A single buffer can be broken into a number of regions where text will
5086 and will not be checked. The definitions of the regions can be user
5087 defined. New applications and improvements made available by this
5088 include:
5089
5090 o URLs are automatically skipped
5091 o EMail message checking is vastly improved.
5092
5093 *** Ispell can highlight the erroneous word even on non-window terminals.
5094
5095 ** Changes to RefTeX mode
5096
5097 RefTeX has been updated in order to make it more usable with very
5098 large projects (like a several volume math book). The parser has been
5099 re-written from scratch. To get maximum speed from RefTeX, check the
5100 section `Optimizations' in the manual.
5101
5102 *** New recursive parser.
5103
5104 The old version of RefTeX created a single large buffer containing the
5105 entire multifile document in order to parse the document. The new
5106 recursive parser scans the individual files.
5107
5108 *** Parsing only part of a document.
5109
5110 Reparsing of changed document parts can now be made faster by enabling
5111 partial scans. To use this feature, read the documentation string of
5112 the variable `reftex-enable-partial-scans' and set the variable to t.
5113
5114 (setq reftex-enable-partial-scans t)
5115
5116 *** Storing parsing information in a file.
5117
5118 This can improve startup times considerably. To turn it on, use
5119
5120 (setq reftex-save-parse-info t)
5121
5122 *** Using multiple selection buffers
5123
5124 If the creation of label selection buffers is too slow (this happens
5125 for large documents), you can reuse these buffers by setting
5126
5127 (setq reftex-use-multiple-selection-buffers t)
5128
5129 *** References to external documents.
5130
5131 The LaTeX package `xr' allows to cross-reference labels in external
5132 documents. RefTeX can provide information about the external
5133 documents as well. To use this feature, set up the \externaldocument
5134 macros required by the `xr' package and rescan the document with
5135 RefTeX. The external labels can then be accessed with the `x' key in
5136 the selection buffer provided by `reftex-reference' (bound to `C-c )').
5137 The `x' key also works in the table of contents buffer.
5138
5139 *** Many more labeled LaTeX environments are recognized by default.
5140
5141 The builtin command list now covers all the standard LaTeX commands,
5142 and all of the major packages included in the LaTeX distribution.
5143
5144 Also, RefTeX now understands the \appendix macro and changes
5145 the enumeration of sections in the *toc* buffer accordingly.
5146
5147 *** Mouse support for selection and *toc* buffers
5148
5149 The mouse can now be used to select items in the selection and *toc*
5150 buffers. See also the new option `reftex-highlight-selection'.
5151
5152 *** New keymaps for selection and table of contents modes.
5153
5154 The selection processes for labels and citation keys, and the table of
5155 contents buffer now have their own keymaps: `reftex-select-label-map',
5156 `reftex-select-bib-map', `reftex-toc-map'. The selection processes
5157 have a number of new keys predefined. In particular, TAB lets you
5158 enter a label with completion. Check the on-the-fly help (press `?'
5159 at the selection prompt) or read the Info documentation to find out
5160 more.
5161
5162 *** Support for the varioref package
5163
5164 The `v' key in the label selection buffer toggles \ref versus \vref.
5165
5166 *** New hooks
5167
5168 Three new hooks can be used to redefine the way labels, references,
5169 and citations are created. These hooks are
5170 `reftex-format-label-function', `reftex-format-ref-function',
5171 `reftex-format-cite-function'.
5172
5173 *** Citations outside LaTeX
5174
5175 The command `reftex-citation' may also be used outside LaTeX (e.g. in
5176 a mail buffer). See the Info documentation for details.
5177
5178 *** Short context is no longer fontified.
5179
5180 The short context in the label menu no longer copies the
5181 fontification from the text in the buffer. If you prefer it to be
5182 fontified, use
5183
5184 (setq reftex-refontify-context t)
5185
5186 ** file-cache-minibuffer-complete now accepts a prefix argument.
5187 With a prefix argument, it does not try to do completion of
5188 the file name within its directory; it only checks for other
5189 directories that contain the same file name.
5190
5191 Thus, given the file name Makefile, and assuming that a file
5192 Makefile.in exists in the same directory, ordinary
5193 file-cache-minibuffer-complete will try to complete Makefile to
5194 Makefile.in and will therefore never look for other directories that
5195 have Makefile. A prefix argument tells it not to look for longer
5196 names such as Makefile.in, so that instead it will look for other
5197 directories--just as if the name were already complete in its present
5198 directory.
5199
5200 ** New modes and packages
5201
5202 *** There is a new alternative major mode for Perl, Cperl mode.
5203 It has many more features than Perl mode, and some people prefer
5204 it, but some do not.
5205
5206 *** There is a new major mode, M-x vhdl-mode, for editing files of VHDL
5207 code.
5208
5209 *** M-x which-function-mode enables a minor mode that displays the
5210 current function name continuously in the mode line, as you move
5211 around in a buffer.
5212
5213 Which Function mode is effective in major modes which support Imenu.
5214
5215 *** Gametree is a major mode for editing game analysis trees. The author
5216 uses it for keeping notes about his postal Chess games, but it should
5217 be helpful for other two-player games as well, as long as they have an
5218 established system of notation similar to Chess.
5219
5220 *** The new minor mode checkdoc-minor-mode provides Emacs Lisp
5221 documentation string checking for style and spelling. The style
5222 guidelines are found in the Emacs Lisp programming manual.
5223
5224 *** The net-utils package makes some common networking features
5225 available in Emacs. Some of these functions are wrappers around
5226 system utilities (ping, nslookup, etc); others are implementations of
5227 simple protocols (finger, whois) in Emacs Lisp. There are also
5228 functions to make simple connections to TCP/IP ports for debugging and
5229 the like.
5230
5231 *** highlight-changes-mode is a minor mode that uses colors to
5232 identify recently changed parts of the buffer text.
5233
5234 *** The new package `midnight' lets you specify things to be done
5235 within Emacs at midnight--by default, kill buffers that you have not
5236 used in a considerable time. To use this feature, customize
5237 the user option `midnight-mode' to t.
5238
5239 *** The file generic-x.el defines a number of simple major modes.
5240
5241 apache-generic-mode: For Apache and NCSA httpd configuration files
5242 samba-generic-mode: Samba configuration files
5243 fvwm-generic-mode: For fvwm initialization files
5244 x-resource-generic-mode: For X resource files
5245 hosts-generic-mode: For hosts files (.rhosts, /etc/hosts, etc)
5246 mailagent-rules-generic-mode: For mailagent .rules files
5247 javascript-generic-mode: For JavaScript files
5248 vrml-generic-mode: For VRML files
5249 java-manifest-generic-mode: For Java MANIFEST files
5250 java-properties-generic-mode: For Java property files
5251 mailrc-generic-mode: For .mailrc files
5252
5253 Platform-specific modes:
5254
5255 prototype-generic-mode: For Solaris/Sys V prototype files
5256 pkginfo-generic-mode: For Solaris/Sys V pkginfo files
5257 alias-generic-mode: For C shell alias files
5258 inf-generic-mode: For MS-Windows INF files
5259 ini-generic-mode: For MS-Windows INI files
5260 reg-generic-mode: For MS-Windows Registry files
5261 bat-generic-mode: For MS-Windows BAT scripts
5262 rc-generic-mode: For MS-Windows Resource files
5263 rul-generic-mode: For InstallShield scripts
5264 \f
5265 * Lisp changes in Emacs 20.3 since the Emacs Lisp Manual was published
5266
5267 ** If you want a Lisp file to be read in unibyte mode,
5268 use -*-unibyte: t;-*- on its first line.
5269 That will force Emacs to read that file in unibyte mode.
5270 Otherwise, the file will be loaded and byte-compiled in multibyte mode.
5271
5272 Thus, each lisp file is read in a consistent way regardless of whether
5273 you started Emacs with --unibyte, so that a Lisp program gives
5274 consistent results regardless of how Emacs was started.
5275
5276 ** The new function assoc-default is useful for searching an alist,
5277 and using a default value if the key is not found there. You can
5278 specify a comparison predicate, so this function is useful for
5279 searching comparing a string against an alist of regular expressions.
5280
5281 ** The functions unibyte-char-to-multibyte and
5282 multibyte-char-to-unibyte convert between unibyte and multibyte
5283 character codes, in a way that is appropriate for the current language
5284 environment.
5285
5286 ** The functions read-event, read-char and read-char-exclusive now
5287 take two optional arguments. PROMPT, if non-nil, specifies a prompt
5288 string. SUPPRESS-INPUT-METHOD, if non-nil, says to disable the
5289 current input method for reading this one event.
5290
5291 ** Two new variables print-escape-nonascii and print-escape-multibyte
5292 now control whether to output certain characters as
5293 backslash-sequences. print-escape-nonascii applies to single-byte
5294 non-ASCII characters; print-escape-multibyte applies to multibyte
5295 characters. Both of these variables are used only when printing
5296 in readable fashion (prin1 uses them, princ does not).
5297 \f
5298 * Lisp changes in Emacs 20.3 before the Emacs Lisp Manual was published
5299
5300 ** Compiled Emacs Lisp files made with the modified "MBSK" version
5301 of Emacs 20.2 do not work in Emacs 20.3.
5302
5303 ** Buffer positions are now measured in characters, as they were
5304 in Emacs 19 and before. This means that (forward-char 1)
5305 always increases point by 1.
5306
5307 The function chars-in-region now just subtracts its arguments. It is
5308 considered obsolete. The function char-boundary-p has been deleted.
5309
5310 See below for additional changes relating to multibyte characters.
5311
5312 ** defcustom, defface and defgroup now accept the keyword `:version'.
5313 Use this to specify in which version of Emacs a certain variable's
5314 default value changed. For example,
5315
5316 (defcustom foo-max 34 "*Maximum number of foo's allowed."
5317 :type 'integer
5318 :group 'foo
5319 :version "20.3")
5320
5321 (defgroup foo-group nil "The foo group."
5322 :version "20.3")
5323
5324 If an entire new group is added or the variables in it have the
5325 default values changed, then just add a `:version' to that group. It
5326 is recommended that new packages added to the distribution contain a
5327 `:version' in the top level group.
5328
5329 This information is used to control the customize-changed-options command.
5330
5331 ** It is now an error to change the value of a symbol whose name
5332 starts with a colon--if it is interned in the standard obarray.
5333
5334 However, setting such a symbol to its proper value, which is that
5335 symbol itself, is not an error. This is for the sake of programs that
5336 support previous Emacs versions by explicitly setting these variables
5337 to themselves.
5338
5339 If you set the variable keyword-symbols-constant-flag to nil,
5340 this error is suppressed, and you can set these symbols to any
5341 values whatever.
5342
5343 ** There is a new debugger command, R.
5344 It evaluates an expression like e, but saves the result
5345 in the buffer *Debugger-record*.
5346
5347 ** Frame-local variables.
5348
5349 You can now make a variable local to various frames. To do this, call
5350 the function make-variable-frame-local; this enables frames to have
5351 local bindings for that variable.
5352
5353 These frame-local bindings are actually frame parameters: you create a
5354 frame-local binding in a specific frame by calling
5355 modify-frame-parameters and specifying the variable name as the
5356 parameter name.
5357
5358 Buffer-local bindings take precedence over frame-local bindings.
5359 Thus, if the current buffer has a buffer-local binding, that binding is
5360 active; otherwise, if the selected frame has a frame-local binding,
5361 that binding is active; otherwise, the default binding is active.
5362
5363 It would not be hard to implement window-local bindings, but it is not
5364 clear that this would be very useful; windows tend to come and go in a
5365 very transitory fashion, so that trying to produce any specific effect
5366 through a window-local binding would not be very robust.
5367
5368 ** `sregexq' and `sregex' are two new functions for constructing
5369 "symbolic regular expressions." These are Lisp expressions that, when
5370 evaluated, yield conventional string-based regexps. The symbolic form
5371 makes it easier to construct, read, and maintain complex patterns.
5372 See the documentation in sregex.el.
5373
5374 ** parse-partial-sexp's return value has an additional element which
5375 is used to pass information along if you pass it to another call to
5376 parse-partial-sexp, starting its scan where the first call ended.
5377 The contents of this field are not yet finalized.
5378
5379 ** eval-region now accepts a fourth optional argument READ-FUNCTION.
5380 If it is non-nil, that function is used instead of `read'.
5381
5382 ** unload-feature by default removes the feature's functions from
5383 known hooks to avoid trouble, but a package providing FEATURE can
5384 define a hook FEATURE-unload-hook to be run by unload-feature instead.
5385
5386 ** read-from-minibuffer no longer returns the argument DEFAULT-VALUE
5387 when the user enters empty input. It now returns the null string, as
5388 it did in Emacs 19. The default value is made available in the
5389 history via M-n, but it is not applied here as a default.
5390
5391 The other, more specialized minibuffer-reading functions continue to
5392 return the default value (not the null string) when the user enters
5393 empty input.
5394
5395 ** The new variable read-buffer-function controls which routine to use
5396 for selecting buffers. For example, if you set this variable to
5397 `iswitchb-read-buffer', iswitchb will be used to read buffer names.
5398 Other functions can also be used if they accept the same arguments as
5399 `read-buffer' and return the selected buffer name as a string.
5400
5401 ** The new function read-passwd reads a password from the terminal,
5402 echoing a period for each character typed. It takes three arguments:
5403 a prompt string, a flag which says "read it twice to make sure", and a
5404 default password to use if the user enters nothing.
5405
5406 ** The variable fill-nobreak-predicate gives major modes a way to
5407 specify not to break a line at certain places. Its value is a
5408 function which is called with no arguments, with point located at the
5409 place where a break is being considered. If the function returns
5410 non-nil, then the line won't be broken there.
5411
5412 ** window-end now takes an optional second argument, UPDATE.
5413 If this is non-nil, then the function always returns an accurate
5414 up-to-date value for the buffer position corresponding to the
5415 end of the window, even if this requires computation.
5416
5417 ** other-buffer now takes an optional argument FRAME
5418 which specifies which frame's buffer list to use.
5419 If it is nil, that means use the selected frame's buffer list.
5420
5421 ** The new variable buffer-display-time, always local in every buffer,
5422 holds the value of (current-time) as of the last time that a window
5423 was directed to display this buffer.
5424
5425 ** It is now meaningful to compare two window-configuration objects
5426 with `equal'. Two window-configuration objects are equal if they
5427 describe equivalent arrangements of windows, in the same frame--in
5428 other words, if they would give the same results if passed to
5429 set-window-configuration.
5430
5431 ** compare-window-configurations is a new function that compares two
5432 window configurations loosely. It ignores differences in saved buffer
5433 positions and scrolling, and considers only the structure and sizes of
5434 windows and the choice of buffers to display.
5435
5436 ** The variable minor-mode-overriding-map-alist allows major modes to
5437 override the key bindings of a minor mode. The elements of this alist
5438 look like the elements of minor-mode-map-alist: (VARIABLE . KEYMAP).
5439
5440 If the VARIABLE in an element of minor-mode-overriding-map-alist has a
5441 non-nil value, the paired KEYMAP is active, and totally overrides the
5442 map (if any) specified for the same variable in minor-mode-map-alist.
5443
5444 minor-mode-overriding-map-alist is automatically local in all buffers,
5445 and it is meant to be set by major modes.
5446
5447 ** The function match-string-no-properties is like match-string
5448 except that it discards all text properties from the result.
5449
5450 ** The function load-average now accepts an optional argument
5451 USE-FLOATS. If it is non-nil, the load average values are returned as
5452 floating point numbers, rather than as integers to be divided by 100.
5453
5454 ** The new variable temporary-file-directory specifies the directory
5455 to use for creating temporary files. The default value is determined
5456 in a reasonable way for your operating system; on GNU and Unix systems
5457 it is based on the TMP and TMPDIR environment variables.
5458
5459 ** Menu changes
5460
5461 *** easymenu.el now uses the new menu item format and supports the
5462 keywords :visible and :filter. The existing keyword :keys is now
5463 better supported.
5464
5465 The variable `easy-menu-precalculate-equivalent-keybindings' controls
5466 a new feature which calculates keyboard equivalents for the menu when
5467 you define the menu. The default is t. If you rarely use menus, you
5468 can set the variable to nil to disable this precalculation feature;
5469 then the calculation is done only if you use the menu bar.
5470
5471 *** A new format for menu items is supported.
5472
5473 In a keymap, a key binding that has the format
5474 (STRING . REAL-BINDING) or (STRING HELP-STRING . REAL-BINDING)
5475 defines a menu item. Now a menu item definition may also be a list that
5476 starts with the symbol `menu-item'.
5477
5478 The format is:
5479 (menu-item ITEM-NAME) or
5480 (menu-item ITEM-NAME REAL-BINDING . ITEM-PROPERTY-LIST)
5481 where ITEM-NAME is an expression which evaluates to the menu item
5482 string, and ITEM-PROPERTY-LIST has the form of a property list.
5483 The supported properties include
5484
5485 :enable FORM Evaluate FORM to determine whether the
5486 item is enabled.
5487 :visible FORM Evaluate FORM to determine whether the
5488 item should appear in the menu.
5489 :filter FILTER-FN
5490 FILTER-FN is a function of one argument,
5491 which will be REAL-BINDING.
5492 It should return a binding to use instead.
5493 :keys DESCRIPTION
5494 DESCRIPTION is a string that describes an equivalent keyboard
5495 binding for for REAL-BINDING. DESCRIPTION is expanded with
5496 `substitute-command-keys' before it is used.
5497 :key-sequence KEY-SEQUENCE
5498 KEY-SEQUENCE is a key-sequence for an equivalent
5499 keyboard binding.
5500 :key-sequence nil
5501 This means that the command normally has no
5502 keyboard equivalent.
5503 :help HELP HELP is the extra help string (not currently used).
5504 :button (TYPE . SELECTED)
5505 TYPE is :toggle or :radio.
5506 SELECTED is a form, to be evaluated, and its
5507 value says whether this button is currently selected.
5508
5509 Buttons are at the moment only simulated by prefixes in the menu.
5510 Eventually ordinary X-buttons may be supported.
5511
5512 (menu-item ITEM-NAME) defines unselectable item.
5513
5514 ** New event types
5515
5516 *** The new event type `mouse-wheel' is generated by a wheel on a
5517 mouse (such as the MS Intellimouse). The event contains a delta that
5518 corresponds to the amount and direction that the wheel is rotated,
5519 which is typically used to implement a scroll or zoom. The format is:
5520
5521 (mouse-wheel POSITION DELTA)
5522
5523 where POSITION is a list describing the position of the event in the
5524 same format as a mouse-click event, and DELTA is a signed number
5525 indicating the number of increments by which the wheel was rotated. A
5526 negative DELTA indicates that the wheel was rotated backwards, towards
5527 the user, and a positive DELTA indicates that the wheel was rotated
5528 forward, away from the user.
5529
5530 As of now, this event type is generated only on MS Windows.
5531
5532 *** The new event type `drag-n-drop' is generated when a group of
5533 files is selected in an application outside of Emacs, and then dragged
5534 and dropped onto an Emacs frame. The event contains a list of
5535 filenames that were dragged and dropped, which are then typically
5536 loaded into Emacs. The format is:
5537
5538 (drag-n-drop POSITION FILES)
5539
5540 where POSITION is a list describing the position of the event in the
5541 same format as a mouse-click event, and FILES is the list of filenames
5542 that were dragged and dropped.
5543
5544 As of now, this event type is generated only on MS Windows.
5545
5546 ** Changes relating to multibyte characters.
5547
5548 *** The variable enable-multibyte-characters is now read-only;
5549 any attempt to set it directly signals an error. The only way
5550 to change this value in an existing buffer is with set-buffer-multibyte.
5551
5552 *** In a string constant, `\ ' now stands for "nothing at all". You
5553 can use it to terminate a hex escape which is followed by a character
5554 that could otherwise be read as part of the hex escape.
5555
5556 *** String indices are now measured in characters, as they were
5557 in Emacs 19 and before.
5558
5559 The function chars-in-string has been deleted.
5560 The function concat-chars has been renamed to `string'.
5561
5562 *** The function set-buffer-multibyte sets the flag in the current
5563 buffer that says whether the buffer uses multibyte representation or
5564 unibyte representation. If the argument is nil, it selects unibyte
5565 representation. Otherwise it selects multibyte representation.
5566
5567 This function does not change the contents of the buffer, viewed
5568 as a sequence of bytes. However, it does change the contents
5569 viewed as characters; a sequence of two bytes which is treated as
5570 one character when the buffer uses multibyte representation
5571 will count as two characters using unibyte representation.
5572
5573 This function sets enable-multibyte-characters to record which
5574 representation is in use. It also adjusts various data in the buffer
5575 (including its markers, overlays and text properties) so that they are
5576 consistent with the new representation.
5577
5578 *** string-make-multibyte takes a string and converts it to multibyte
5579 representation. Most of the time, you don't need to care
5580 about the representation, because Emacs converts when necessary;
5581 however, it makes a difference when you compare strings.
5582
5583 The conversion of non-ASCII characters works by adding the value of
5584 nonascii-insert-offset to each character, or by translating them
5585 using the table nonascii-translation-table.
5586
5587 *** string-make-unibyte takes a string and converts it to unibyte
5588 representation. Most of the time, you don't need to care about the
5589 representation, but it makes a difference when you compare strings.
5590
5591 The conversion from multibyte to unibyte representation
5592 loses information; the only time Emacs performs it automatically
5593 is when inserting a multibyte string into a unibyte buffer.
5594
5595 *** string-as-multibyte takes a string, and returns another string
5596 which contains the same bytes, but treats them as multibyte.
5597
5598 *** string-as-unibyte takes a string, and returns another string
5599 which contains the same bytes, but treats them as unibyte.
5600
5601 *** The new function compare-strings lets you compare
5602 portions of two strings. Unibyte strings are converted to multibyte,
5603 so that a unibyte string can match a multibyte string.
5604 You can specify whether to ignore case or not.
5605
5606 *** assoc-ignore-case now uses compare-strings so that
5607 it can treat unibyte and multibyte strings as equal.
5608
5609 *** Regular expression operations and buffer string searches now
5610 convert the search pattern to multibyte or unibyte to accord with the
5611 buffer or string being searched.
5612
5613 One consequence is that you cannot always use \200-\377 inside of
5614 [...] to match all non-ASCII characters. This does still work when
5615 searching or matching a unibyte buffer or string, but not when
5616 searching or matching a multibyte string. Unfortunately, there is no
5617 obvious choice of syntax to use within [...] for that job. But, what
5618 you want is just to match all non-ASCII characters, the regular
5619 expression [^\0-\177] works for it.
5620
5621 *** Structure of coding system changed.
5622
5623 All coding systems (including aliases and subsidiaries) are named
5624 by symbols; the symbol's `coding-system' property is a vector
5625 which defines the coding system. Aliases share the same vector
5626 as the principal name, so that altering the contents of this
5627 vector affects the principal name and its aliases. You can define
5628 your own alias name of a coding system by the function
5629 define-coding-system-alias.
5630
5631 The coding system definition includes a property list of its own. Use
5632 the new functions `coding-system-get' and `coding-system-put' to
5633 access such coding system properties as post-read-conversion,
5634 pre-write-conversion, character-translation-table-for-decode,
5635 character-translation-table-for-encode, mime-charset, and
5636 safe-charsets. For instance, (coding-system-get 'iso-latin-1
5637 'mime-charset) gives the corresponding MIME-charset parameter
5638 `iso-8859-1'.
5639
5640 Among the coding system properties listed above, safe-charsets is new.
5641 The value of this property is a list of character sets which this
5642 coding system can correctly encode and decode. For instance:
5643 (coding-system-get 'iso-latin-1 'safe-charsets) => (ascii latin-iso8859-1)
5644
5645 Here, "correctly encode" means that the encoded character sets can
5646 also be handled safely by systems other than Emacs as far as they
5647 are capable of that coding system. Though, Emacs itself can encode
5648 the other character sets and read it back correctly.
5649
5650 *** The new function select-safe-coding-system can be used to find a
5651 proper coding system for encoding the specified region or string.
5652 This function requires a user interaction.
5653
5654 *** The new functions find-coding-systems-region and
5655 find-coding-systems-string are helper functions used by
5656 select-safe-coding-system. They return a list of all proper coding
5657 systems to encode a text in some region or string. If you don't want
5658 a user interaction, use one of these functions instead of
5659 select-safe-coding-system.
5660
5661 *** The explicit encoding and decoding functions, such as
5662 decode-coding-region and encode-coding-string, now set
5663 last-coding-system-used to reflect the actual way encoding or decoding
5664 was done.
5665
5666 *** The new function detect-coding-with-language-environment can be
5667 used to detect a coding system of text according to priorities of
5668 coding systems used by some specific language environment.
5669
5670 *** The functions detect-coding-region and detect-coding-string always
5671 return a list if the arg HIGHEST is nil. Thus, if only ASCII
5672 characters are found, they now return a list of single element
5673 `undecided' or its subsidiaries.
5674
5675 *** The new functions coding-system-change-eol-conversion and
5676 coding-system-change-text-conversion can be used to get a different
5677 coding system than what specified only in how end-of-line or text is
5678 converted.
5679
5680 *** The new function set-selection-coding-system can be used to set a
5681 coding system for communicating with other X clients.
5682
5683 *** The function `map-char-table' now passes as argument only valid
5684 character codes, plus generic characters that stand for entire
5685 character sets or entire subrows of a character set. In other words,
5686 each time `map-char-table' calls its FUNCTION argument, the key value
5687 either will be a valid individual character code, or will stand for a
5688 range of characters.
5689
5690 *** The new function `char-valid-p' can be used for checking whether a
5691 Lisp object is a valid character code or not.
5692
5693 *** The new function `charset-after' returns a charset of a character
5694 in the current buffer at position POS.
5695
5696 *** Input methods are now implemented using the variable
5697 input-method-function. If this is non-nil, its value should be a
5698 function; then, whenever Emacs reads an input event that is a printing
5699 character with no modifier bits, it calls that function, passing the
5700 event as an argument. Often this function will read more input, first
5701 binding input-method-function to nil.
5702
5703 The return value should be a list of the events resulting from input
5704 method processing. These events will be processed sequentially as
5705 input, before resorting to unread-command-events. Events returned by
5706 the input method function are not passed to the input method function,
5707 not even if they are printing characters with no modifier bits.
5708
5709 The input method function is not called when reading the second and
5710 subsequent events of a key sequence.
5711
5712 *** You can customize any language environment by using
5713 set-language-environment-hook and exit-language-environment-hook.
5714
5715 The hook `exit-language-environment-hook' should be used to undo
5716 customizations that you made with set-language-environment-hook. For
5717 instance, if you set up a special key binding for a specific language
5718 environment by set-language-environment-hook, you should set up
5719 exit-language-environment-hook to restore the normal key binding.
5720 \f
5721 * Changes in Emacs 20.1
5722
5723 ** Emacs has a new facility for customization of its many user
5724 options. It is called M-x customize. With this facility you can look
5725 at the many user options in an organized way; they are grouped into a
5726 tree structure.
5727
5728 M-x customize also knows what sorts of values are legitimate for each
5729 user option and ensures that you don't use invalid values.
5730
5731 With M-x customize, you can set options either for the present Emacs
5732 session or permanently. (Permanent settings are stored automatically
5733 in your .emacs file.)
5734
5735 ** Scroll bars are now on the left side of the window.
5736 You can change this with M-x customize-option scroll-bar-mode.
5737
5738 ** The mode line no longer includes the string `Emacs'.
5739 This makes more space in the mode line for other information.
5740
5741 ** When you select a region with the mouse, it is highlighted
5742 immediately afterward. At that time, if you type the DELETE key, it
5743 kills the region.
5744
5745 The BACKSPACE key, and the ASCII character DEL, do not do this; they
5746 delete the character before point, as usual.
5747
5748 ** In an incremental search the whole current match is highlighted
5749 on terminals which support this. (You can disable this feature
5750 by setting search-highlight to nil.)
5751
5752 ** In the minibuffer, in some cases, you can now use M-n to
5753 insert the default value into the minibuffer as text. In effect,
5754 the default value (if the minibuffer routines know it) is tacked
5755 onto the history "in the future". (The more normal use of the
5756 history list is to use M-p to insert minibuffer input used in the
5757 past.)
5758
5759 ** In Text mode, now only blank lines separate paragraphs.
5760 This makes it possible to get the full benefit of Adaptive Fill mode
5761 in Text mode, and other modes derived from it (such as Mail mode).
5762 TAB in Text mode now runs the command indent-relative; this
5763 makes a practical difference only when you use indented paragraphs.
5764
5765 As a result, the old Indented Text mode is now identical to Text mode,
5766 and is an alias for it.
5767
5768 If you want spaces at the beginning of a line to start a paragraph,
5769 use the new mode, Paragraph Indent Text mode.
5770
5771 ** Scrolling changes
5772
5773 *** Scroll commands to scroll a whole screen now preserve the screen
5774 position of the cursor, if scroll-preserve-screen-position is non-nil.
5775
5776 In this mode, if you scroll several screens back and forth, finishing
5777 on the same screen where you started, the cursor goes back to the line
5778 where it started.
5779
5780 *** If you set scroll-conservatively to a small number, then when you
5781 move point a short distance off the screen, Emacs will scroll the
5782 screen just far enough to bring point back on screen, provided that
5783 does not exceed `scroll-conservatively' lines.
5784
5785 *** The new variable scroll-margin says how close point can come to the
5786 top or bottom of a window. It is a number of screen lines; if point
5787 comes within that many lines of the top or bottom of the window, Emacs
5788 recenters the window.
5789
5790 ** International character set support (MULE)
5791
5792 Emacs now supports a wide variety of international character sets,
5793 including European variants of the Latin alphabet, as well as Chinese,
5794 Devanagari (Hindi and Marathi), Ethiopian, Greek, IPA, Japanese,
5795 Korean, Lao, Russian, Thai, Tibetan, and Vietnamese scripts. These
5796 features have been merged from the modified version of Emacs known as
5797 MULE (for "MULti-lingual Enhancement to GNU Emacs")
5798
5799 Users of these scripts have established many more-or-less standard
5800 coding systems for storing files. Emacs uses a single multibyte
5801 character encoding within Emacs buffers; it can translate from a wide
5802 variety of coding systems when reading a file and can translate back
5803 into any of these coding systems when saving a file.
5804
5805 Keyboards, even in the countries where these character sets are used,
5806 generally don't have keys for all the characters in them. So Emacs
5807 supports various "input methods", typically one for each script or
5808 language, to make it possible to type them.
5809
5810 The Emacs internal multibyte encoding represents a non-ASCII
5811 character as a sequence of bytes in the range 0200 through 0377.
5812
5813 The new prefix key C-x RET is used for commands that pertain
5814 to multibyte characters, coding systems, and input methods.
5815
5816 You can disable multibyte character support as follows:
5817
5818 (setq-default enable-multibyte-characters nil)
5819
5820 Calling the function standard-display-european turns off multibyte
5821 characters, unless you specify a non-nil value for the second
5822 argument, AUTO. This provides compatibility for people who are
5823 already using standard-display-european to continue using unibyte
5824 characters for their work until they want to change.
5825
5826 *** Input methods
5827
5828 An input method is a kind of character conversion which is designed
5829 specifically for interactive input. In Emacs, typically each language
5830 has its own input method (though sometimes several languages which use
5831 the same characters can share one input method). Some languages
5832 support several input methods.
5833
5834 The simplest kind of input method works by mapping ASCII letters into
5835 another alphabet. This is how the Greek and Russian input methods
5836 work.
5837
5838 A more powerful technique is composition: converting sequences of
5839 characters into one letter. Many European input methods use
5840 composition to produce a single non-ASCII letter from a sequence which
5841 consists of a letter followed by diacritics. For example, a' is one
5842 sequence of two characters that might be converted into a single
5843 letter.
5844
5845 The input methods for syllabic scripts typically use mapping followed
5846 by conversion. The input methods for Thai and Korean work this way.
5847 First, letters are mapped into symbols for particular sounds or tone
5848 marks; then, sequences of these which make up a whole syllable are
5849 mapped into one syllable sign--most often a "composite character".
5850
5851 None of these methods works very well for Chinese and Japanese, so
5852 they are handled specially. First you input a whole word using
5853 phonetic spelling; then, after the word is in the buffer, Emacs
5854 converts it into one or more characters using a large dictionary.
5855
5856 Since there is more than one way to represent a phonetically spelled
5857 word using Chinese characters, Emacs can only guess which one to use;
5858 typically these input methods give you a way to say "guess again" if
5859 the first guess is wrong.
5860
5861 *** The command C-x RET m (toggle-enable-multibyte-characters)
5862 turns multibyte character support on or off for the current buffer.
5863
5864 If multibyte character support is turned off in a buffer, then each
5865 byte is a single character, even codes 0200 through 0377--exactly as
5866 they did in Emacs 19.34. This includes the features for support for
5867 the European characters, ISO Latin-1 and ISO Latin-2.
5868
5869 However, there is no need to turn off multibyte character support to
5870 use ISO Latin-1 or ISO Latin-2; the Emacs multibyte character set
5871 includes all the characters in these character sets, and Emacs can
5872 translate automatically to and from either one.
5873
5874 *** Visiting a file in unibyte mode.
5875
5876 Turning off multibyte character support in the buffer after visiting a
5877 file with multibyte code conversion will display the multibyte
5878 sequences already in the buffer, byte by byte. This is probably not
5879 what you want.
5880
5881 If you want to edit a file of unibyte characters (Latin-1, for
5882 example), you can do it by specifying `no-conversion' as the coding
5883 system when reading the file. This coding system also turns off
5884 multibyte characters in that buffer.
5885
5886 If you turn off multibyte character support entirely, this turns off
5887 character conversion as well.
5888
5889 *** Displaying international characters on X Windows.
5890
5891 A font for X typically displays just one alphabet or script.
5892 Therefore, displaying the entire range of characters Emacs supports
5893 requires using many fonts.
5894
5895 Therefore, Emacs now supports "fontsets". Each fontset is a
5896 collection of fonts, each assigned to a range of character codes.
5897
5898 A fontset has a name, like a font. Individual fonts are defined by
5899 the X server; fontsets are defined within Emacs itself. But once you
5900 have defined a fontset, you can use it in a face or a frame just as
5901 you would use a font.
5902
5903 If a fontset specifies no font for a certain character, or if it
5904 specifies a font that does not exist on your system, then it cannot
5905 display that character. It will display an empty box instead.
5906
5907 The fontset height and width are determined by the ASCII characters
5908 (that is, by the font in the fontset which is used for ASCII
5909 characters). If another font in the fontset has a different height,
5910 or the wrong width, then characters assigned to that font are clipped,
5911 and displayed within a box if highlight-wrong-size-font is non-nil.
5912
5913 *** Defining fontsets.
5914
5915 Emacs does not use any fontset by default. Its default font is still
5916 chosen as in previous versions. You can tell Emacs to use a fontset
5917 with the `-fn' option or the `Font' X resource.
5918
5919 Emacs creates a standard fontset automatically according to the value
5920 of standard-fontset-spec. This fontset's short name is
5921 `fontset-standard'. Bold, italic, and bold-italic variants of the
5922 standard fontset are created automatically.
5923
5924 If you specify a default ASCII font with the `Font' resource or `-fn'
5925 argument, a fontset is generated from it. This works by replacing the
5926 FOUNDARY, FAMILY, ADD_STYLE, and AVERAGE_WIDTH fields of the font name
5927 with `*' then using this to specify a fontset. This fontset's short
5928 name is `fontset-startup'.
5929
5930 Emacs checks resources of the form Fontset-N where N is 0, 1, 2...
5931 The resource value should have this form:
5932 FONTSET-NAME, [CHARSET-NAME:FONT-NAME]...
5933 FONTSET-NAME should have the form of a standard X font name, except:
5934 * most fields should be just the wild card "*".
5935 * the CHARSET_REGISTRY field should be "fontset"
5936 * the CHARSET_ENCODING field can be any nickname of the fontset.
5937 The construct CHARSET-NAME:FONT-NAME can be repeated any number
5938 of times; each time specifies the font for one character set.
5939 CHARSET-NAME should be the name name of a character set, and
5940 FONT-NAME should specify an actual font to use for that character set.
5941
5942 Each of these fontsets has an alias which is made from the
5943 last two font name fields, CHARSET_REGISTRY and CHARSET_ENCODING.
5944 You can refer to the fontset by that alias or by its full name.
5945
5946 For any character sets that you don't mention, Emacs tries to choose a
5947 font by substituting into FONTSET-NAME. For instance, with the
5948 following resource,
5949 Emacs*Fontset-0: -*-fixed-medium-r-normal-*-24-*-*-*-*-*-fontset-24
5950 the font for ASCII is generated as below:
5951 -*-fixed-medium-r-normal-*-24-*-ISO8859-1
5952 Here is the substitution rule:
5953 Change CHARSET_REGISTRY and CHARSET_ENCODING to that of the charset
5954 defined in the variable x-charset-registries. For instance, ASCII has
5955 the entry (ascii . "ISO8859-1") in this variable. Then, reduce
5956 sequences of wild cards -*-...-*- with a single wildcard -*-.
5957 (This is to prevent use of auto-scaled fonts.)
5958
5959 The function which processes the fontset resource value to create the
5960 fontset is called create-fontset-from-fontset-spec. You can also call
5961 that function explicitly to create a fontset.
5962
5963 With the X resource Emacs.Font, you can specify a fontset name just
5964 like an actual font name. But be careful not to specify a fontset
5965 name in a wildcard resource like Emacs*Font--that tries to specify the
5966 fontset for other purposes including menus, and they cannot handle
5967 fontsets.
5968
5969 *** The command M-x set-language-environment sets certain global Emacs
5970 defaults for a particular choice of language.
5971
5972 Selecting a language environment typically specifies a default input
5973 method and which coding systems to recognize automatically when
5974 visiting files. However, it does not try to reread files you have
5975 already visited; the text in those buffers is not affected. The
5976 language environment may also specify a default choice of coding
5977 system for new files that you create.
5978
5979 It makes no difference which buffer is current when you use
5980 set-language-environment, because these defaults apply globally to the
5981 whole Emacs session.
5982
5983 For example, M-x set-language-environment RET Latin-1 RET
5984 chooses the Latin-1 character set. In the .emacs file, you can do this
5985 with (set-language-environment "Latin-1").
5986
5987 *** The command C-x RET f (set-buffer-file-coding-system)
5988 specifies the file coding system for the current buffer. This
5989 specifies what sort of character code translation to do when saving
5990 the file. As an argument, you must specify the name of one of the
5991 coding systems that Emacs supports.
5992
5993 *** The command C-x RET c (universal-coding-system-argument)
5994 lets you specify a coding system when you read or write a file.
5995 This command uses the minibuffer to read a coding system name.
5996 After you exit the minibuffer, the specified coding system
5997 is used for *the immediately following command*.
5998
5999 So if the immediately following command is a command to read or
6000 write a file, it uses the specified coding system for that file.
6001
6002 If the immediately following command does not use the coding system,
6003 then C-x RET c ultimately has no effect.
6004
6005 For example, C-x RET c iso-8859-1 RET C-x C-f temp RET
6006 visits the file `temp' treating it as ISO Latin-1.
6007
6008 *** You can specify the coding system for a file using the -*-
6009 construct. Include `coding: CODINGSYSTEM;' inside the -*-...-*-
6010 to specify use of coding system CODINGSYSTEM. You can also
6011 specify the coding system in a local variable list at the end
6012 of the file.
6013
6014 *** The command C-x RET t (set-terminal-coding-system) specifies
6015 the coding system for terminal output. If you specify a character
6016 code for terminal output, all characters output to the terminal are
6017 translated into that character code.
6018
6019 This feature is useful for certain character-only terminals built in
6020 various countries to support the languages of those countries.
6021
6022 By default, output to the terminal is not translated at all.
6023
6024 *** The command C-x RET k (set-keyboard-coding-system) specifies
6025 the coding system for keyboard input.
6026
6027 Character code translation of keyboard input is useful for terminals
6028 with keys that send non-ASCII graphic characters--for example,
6029 some terminals designed for ISO Latin-1 or subsets of it.
6030
6031 By default, keyboard input is not translated at all.
6032
6033 Character code translation of keyboard input is similar to using an
6034 input method, in that both define sequences of keyboard input that
6035 translate into single characters. However, input methods are designed
6036 to be convenient for interactive use, while the code translations are
6037 designed to work with terminals.
6038
6039 *** The command C-x RET p (set-buffer-process-coding-system)
6040 specifies the coding system for input and output to a subprocess.
6041 This command applies to the current buffer; normally, each subprocess
6042 has its own buffer, and thus you can use this command to specify
6043 translation to and from a particular subprocess by giving the command
6044 in the corresponding buffer.
6045
6046 By default, process input and output are not translated at all.
6047
6048 *** The variable file-name-coding-system specifies the coding system
6049 to use for encoding file names before operating on them.
6050 It is also used for decoding file names obtained from the system.
6051
6052 *** The command C-\ (toggle-input-method) activates or deactivates
6053 an input method. If no input method has been selected before, the
6054 command prompts for you to specify the language and input method you
6055 want to use.
6056
6057 C-u C-\ (select-input-method) lets you switch to a different input
6058 method. C-h C-\ (or C-h I) describes the current input method.
6059
6060 *** Some input methods remap the keyboard to emulate various keyboard
6061 layouts commonly used for particular scripts. How to do this
6062 remapping properly depends on your actual keyboard layout. To specify
6063 which layout your keyboard has, use M-x quail-set-keyboard-layout.
6064
6065 *** The command C-h C (describe-coding-system) displays
6066 the coding systems currently selected for various purposes, plus
6067 related information.
6068
6069 *** The command C-h h (view-hello-file) displays a file called
6070 HELLO, which has examples of text in many languages, using various
6071 scripts.
6072
6073 *** The command C-h L (describe-language-support) displays
6074 information about the support for a particular language.
6075 You specify the language as an argument.
6076
6077 *** The mode line now contains a letter or character that identifies
6078 the coding system used in the visited file. It normally follows the
6079 first dash.
6080
6081 A dash indicates the default state of affairs: no code conversion
6082 (except CRLF => newline if appropriate). `=' means no conversion
6083 whatsoever. The ISO 8859 coding systems are represented by digits
6084 1 through 9. Other coding systems are represented by letters:
6085
6086 A alternativnyj (Russian)
6087 B big5 (Chinese)
6088 C cn-gb-2312 (Chinese)
6089 C iso-2022-cn (Chinese)
6090 D in-is13194-devanagari (Indian languages)
6091 E euc-japan (Japanese)
6092 I iso-2022-cjk or iso-2022-ss2 (Chinese, Japanese, Korean)
6093 J junet (iso-2022-7) or old-jis (iso-2022-jp-1978-irv) (Japanese)
6094 K euc-korea (Korean)
6095 R koi8 (Russian)
6096 Q tibetan
6097 S shift_jis (Japanese)
6098 T lao
6099 T tis620 (Thai)
6100 V viscii or vscii (Vietnamese)
6101 i iso-2022-lock (Chinese, Japanese, Korean)
6102 k iso-2022-kr (Korean)
6103 v viqr (Vietnamese)
6104 z hz (Chinese)
6105
6106 When you are using a character-only terminal (not a window system),
6107 two additional characters appear in between the dash and the file
6108 coding system. These two characters describe the coding system for
6109 keyboard input, and the coding system for terminal output.
6110
6111 *** The new variable rmail-file-coding-system specifies the code
6112 conversion to use for RMAIL files. The default value is nil.
6113
6114 When you read mail with Rmail, each message is decoded automatically
6115 into Emacs' internal format. This has nothing to do with
6116 rmail-file-coding-system. That variable controls reading and writing
6117 Rmail files themselves.
6118
6119 *** The new variable sendmail-coding-system specifies the code
6120 conversion for outgoing mail. The default value is nil.
6121
6122 Actually, there are three different ways of specifying the coding system
6123 for sending mail:
6124
6125 - If you use C-x RET f in the mail buffer, that takes priority.
6126 - Otherwise, if you set sendmail-coding-system non-nil, that specifies it.
6127 - Otherwise, the default coding system for new files is used,
6128 if that is non-nil. That comes from your language environment.
6129 - Otherwise, Latin-1 is used.
6130
6131 *** The command C-h t (help-with-tutorial) accepts a prefix argument
6132 to specify the language for the tutorial file. Currently, English,
6133 Japanese, Korean and Thai are supported. We welcome additional
6134 translations.
6135
6136 ** An easy new way to visit a file with no code or format conversion
6137 of any kind: Use M-x find-file-literally. There is also a command
6138 insert-file-literally which inserts a file into the current buffer
6139 without any conversion.
6140
6141 ** C-q's handling of octal character codes is changed.
6142 You can now specify any number of octal digits.
6143 RET terminates the digits and is discarded;
6144 any other non-digit terminates the digits and is then used as input.
6145
6146 ** There are new commands for looking up Info documentation for
6147 functions, variables and file names used in your programs.
6148
6149 Type M-x info-lookup-symbol to look up a symbol in the buffer at point.
6150 Type M-x info-lookup-file to look up a file in the buffer at point.
6151
6152 Precisely which Info files are used to look it up depends on the major
6153 mode. For example, in C mode, the GNU libc manual is used.
6154
6155 ** M-TAB in most programming language modes now runs the command
6156 complete-symbol. This command performs completion on the symbol name
6157 in the buffer before point.
6158
6159 With a numeric argument, it performs completion based on the set of
6160 symbols documented in the Info files for the programming language that
6161 you are using.
6162
6163 With no argument, it does completion based on the current tags tables,
6164 just like the old binding of M-TAB (complete-tag).
6165
6166 ** File locking works with NFS now.
6167
6168 The lock file for FILENAME is now a symbolic link named .#FILENAME,
6169 in the same directory as FILENAME.
6170
6171 This means that collision detection between two different machines now
6172 works reasonably well; it also means that no file server or directory
6173 can become a bottleneck.
6174
6175 The new method does have drawbacks. It means that collision detection
6176 does not operate when you edit a file in a directory where you cannot
6177 create new files. Collision detection also doesn't operate when the
6178 file server does not support symbolic links. But these conditions are
6179 rare, and the ability to have collision detection while using NFS is
6180 so useful that the change is worth while.
6181
6182 When Emacs or a system crashes, this may leave behind lock files which
6183 are stale. So you may occasionally get warnings about spurious
6184 collisions. When you determine that the collision is spurious, just
6185 tell Emacs to go ahead anyway.
6186
6187 ** If you wish to use Show Paren mode to display matching parentheses,
6188 it is no longer sufficient to load paren.el. Instead you must call
6189 show-paren-mode.
6190
6191 ** If you wish to use Delete Selection mode to replace a highlighted
6192 selection when you insert new text, it is no longer sufficient to load
6193 delsel.el. Instead you must call the function delete-selection-mode.
6194
6195 ** If you wish to use Partial Completion mode to complete partial words
6196 within symbols or filenames, it is no longer sufficient to load
6197 complete.el. Instead you must call the function partial-completion-mode.
6198
6199 ** If you wish to use uniquify to rename buffers for you,
6200 it is no longer sufficient to load uniquify.el. You must also
6201 set uniquify-buffer-name-style to one of the non-nil legitimate values.
6202
6203 ** Changes in View mode.
6204
6205 *** Several new commands are available in View mode.
6206 Do H in view mode for a list of commands.
6207
6208 *** There are two new commands for entering View mode:
6209 view-file-other-frame and view-buffer-other-frame.
6210
6211 *** Exiting View mode does a better job of restoring windows to their
6212 previous state.
6213
6214 *** New customization variable view-scroll-auto-exit. If non-nil,
6215 scrolling past end of buffer makes view mode exit.
6216
6217 *** New customization variable view-exits-all-viewing-windows. If
6218 non-nil, view-mode will at exit restore all windows viewing buffer,
6219 not just the selected window.
6220
6221 *** New customization variable view-read-only. If non-nil, visiting a
6222 read-only file automatically enters View mode, and toggle-read-only
6223 turns View mode on or off.
6224
6225 *** New customization variable view-remove-frame-by-deleting controls
6226 how to remove a not needed frame at view mode exit. If non-nil,
6227 delete the frame, if nil make an icon of it.
6228
6229 ** C-x v l, the command to print a file's version control log,
6230 now positions point at the entry for the file's current branch version.
6231
6232 ** C-x v =, the command to compare a file with the last checked-in version,
6233 has a new feature. If the file is currently not locked, so that it is
6234 presumably identical to the last checked-in version, the command now asks
6235 which version to compare with.
6236
6237 ** When using hideshow.el, incremental search can temporarily show hidden
6238 blocks if a match is inside the block.
6239
6240 The block is hidden again if the search is continued and the next match
6241 is outside the block. By customizing the variable
6242 isearch-hide-immediately you can choose to hide all the temporarily
6243 shown blocks only when exiting from incremental search.
6244
6245 By customizing the variable hs-isearch-open you can choose what kind
6246 of blocks to temporarily show during isearch: comment blocks, code
6247 blocks, all of them or none.
6248
6249 ** The new command C-x 4 0 (kill-buffer-and-window) kills the
6250 current buffer and deletes the selected window. It asks for
6251 confirmation first.
6252
6253 ** C-x C-w, which saves the buffer into a specified file name,
6254 now changes the major mode according to that file name.
6255 However, the mode will not be changed if
6256 (1) a local variables list or the `-*-' line specifies a major mode, or
6257 (2) the current major mode is a "special" mode,
6258 not suitable for ordinary files, or
6259 (3) the new file name does not particularly specify any mode.
6260
6261 This applies to M-x set-visited-file-name as well.
6262
6263 However, if you set change-major-mode-with-file-name to nil, then
6264 these commands do not change the major mode.
6265
6266 ** M-x occur changes.
6267
6268 *** If the argument to M-x occur contains upper case letters,
6269 it performs a case-sensitive search.
6270
6271 *** In the *Occur* buffer made by M-x occur,
6272 if you type g or M-x revert-buffer, this repeats the search
6273 using the same regular expression and the same buffer as before.
6274
6275 ** In Transient Mark mode, the region in any one buffer is highlighted
6276 in just one window at a time. At first, it is highlighted in the
6277 window where you set the mark. The buffer's highlighting remains in
6278 that window unless you select to another window which shows the same
6279 buffer--then the highlighting moves to that window.
6280
6281 ** The feature to suggest key bindings when you use M-x now operates
6282 after the command finishes. The message suggesting key bindings
6283 appears temporarily in the echo area. The previous echo area contents
6284 come back after a few seconds, in case they contain useful information.
6285
6286 ** Each frame now independently records the order for recently
6287 selected buffers, so that the default for C-x b is now based on the
6288 buffers recently selected in the selected frame.
6289
6290 ** Outline mode changes.
6291
6292 *** Outline mode now uses overlays (this is the former noutline.el).
6293
6294 *** Incremental searches skip over invisible text in Outline mode.
6295
6296 ** When a minibuffer window is active but not the selected window, if
6297 you try to use the minibuffer, you used to get a nested minibuffer.
6298 Now, this not only gives an error, it also cancels the minibuffer that
6299 was already active.
6300
6301 The motive for this change is so that beginning users do not
6302 unknowingly move away from minibuffers, leaving them active, and then
6303 get confused by it.
6304
6305 If you want to be able to have recursive minibuffers, you must
6306 set enable-recursive-minibuffers to non-nil.
6307
6308 ** Changes in dynamic abbrevs.
6309
6310 *** Expanding dynamic abbrevs with M-/ is now smarter about case
6311 conversion. If the expansion has mixed case not counting the first
6312 character, and the abbreviation matches the beginning of the expansion
6313 including case, then the expansion is copied verbatim.
6314
6315 The expansion is also copied verbatim if the abbreviation itself has
6316 mixed case. And using SPC M-/ to copy an additional word always
6317 copies it verbatim except when the previous copied word is all caps.
6318
6319 *** The values of `dabbrev-case-replace' and `dabbrev-case-fold-search'
6320 are no longer Lisp expressions. They have simply three possible
6321 values.
6322
6323 `dabbrev-case-replace' has these three values: nil (don't preserve
6324 case), t (do), or `case-replace' (do like M-x query-replace).
6325 `dabbrev-case-fold-search' has these three values: nil (don't ignore
6326 case), t (do), or `case-fold-search' (do like search).
6327
6328 ** Minibuffer history lists are truncated automatically now to a
6329 certain length. The variable history-length specifies how long they
6330 can be. The default value is 30.
6331
6332 ** Changes in Mail mode.
6333
6334 *** The key C-x m no longer runs the `mail' command directly.
6335 Instead, it runs the command `compose-mail', which invokes the mail
6336 composition mechanism you have selected with the variable
6337 `mail-user-agent'. The default choice of user agent is
6338 `sendmail-user-agent', which gives behavior compatible with the old
6339 behavior.
6340
6341 C-x 4 m now runs compose-mail-other-window, and C-x 5 m runs
6342 compose-mail-other-frame.
6343
6344 *** While composing a reply to a mail message, from Rmail, you can use
6345 the command C-c C-r to cite just the region from the message you are
6346 replying to. This copies the text which is the selected region in the
6347 buffer that shows the original message.
6348
6349 *** The command C-c C-i inserts a file at the end of the message,
6350 with separator lines around the contents.
6351
6352 *** The command M-x expand-mail-aliases expands all mail aliases
6353 in suitable mail headers. Emacs automatically extracts mail alias
6354 definitions from your mail alias file (e.g., ~/.mailrc). You do not
6355 need to expand mail aliases yourself before sending mail.
6356
6357 *** New features in the mail-complete command.
6358
6359 **** The mail-complete command now inserts the user's full name,
6360 for local users or if that is known. The variable mail-complete-style
6361 controls the style to use, and whether to do this at all.
6362 Its values are like those of mail-from-style.
6363
6364 **** The variable mail-passwd-command lets you specify a shell command
6365 to run to fetch a set of password-entries that add to the ones in
6366 /etc/passwd.
6367
6368 **** The variable mail-passwd-file now specifies a list of files to read
6369 to get the list of user ids. By default, one file is used:
6370 /etc/passwd.
6371
6372 ** You can "quote" a file name to inhibit special significance of
6373 special syntax, by adding `/:' to the beginning. Thus, if you have a
6374 directory named `/foo:', you can prevent it from being treated as a
6375 reference to a remote host named `foo' by writing it as `/:/foo:'.
6376
6377 Emacs uses this new construct automatically when necessary, such as
6378 when you start it with a working directory whose name might otherwise
6379 be taken to be magic.
6380
6381 ** There is a new command M-x grep-find which uses find to select
6382 files to search through, and grep to scan them. The output is
6383 available in a Compile mode buffer, as with M-x grep.
6384
6385 M-x grep now uses the -e option if the grep program supports that.
6386 (-e prevents problems if the search pattern starts with a dash.)
6387
6388 ** In Dired, the & command now flags for deletion the files whose names
6389 suggest they are probably not needed in the long run.
6390
6391 In Dired, * is now a prefix key for mark-related commands.
6392
6393 new key dired.el binding old key
6394 ------- ---------------- -------
6395 * c dired-change-marks c
6396 * m dired-mark m
6397 * * dired-mark-executables * (binding deleted)
6398 * / dired-mark-directories / (binding deleted)
6399 * @ dired-mark-symlinks @ (binding deleted)
6400 * u dired-unmark u
6401 * DEL dired-unmark-backward DEL
6402 * ? dired-unmark-all-files M-C-?
6403 * ! dired-unmark-all-marks
6404 * % dired-mark-files-regexp % m
6405 * C-n dired-next-marked-file M-}
6406 * C-p dired-prev-marked-file M-{
6407
6408 ** Rmail changes.
6409
6410 *** When Rmail cannot convert your incoming mail into Babyl format, it
6411 saves the new mail in the file RMAILOSE.n, where n is an integer
6412 chosen to make a unique name. This way, Rmail will not keep crashing
6413 each time you run it.
6414
6415 *** In Rmail, the variable rmail-summary-line-count-flag now controls
6416 whether to include the line count in the summary. Non-nil means yes.
6417
6418 *** In Rmail summary buffers, d and C-d (the commands to delete
6419 messages) now take repeat counts as arguments. A negative argument
6420 means to move in the opposite direction.
6421
6422 *** In Rmail, the t command now takes an optional argument which lets
6423 you specify whether to show the message headers in full or pruned.
6424
6425 *** In Rmail, the new command w (rmail-output-body-to-file) writes
6426 just the body of the current message into a file, without the headers.
6427 It takes the file name from the message subject, by default, but you
6428 can edit that file name in the minibuffer before it is actually used
6429 for output.
6430
6431 ** Gnus changes.
6432
6433 *** nntp.el has been totally rewritten in an asynchronous fashion.
6434
6435 *** Article prefetching functionality has been moved up into
6436 Gnus.
6437
6438 *** Scoring can now be performed with logical operators like
6439 `and', `or', `not', and parent redirection.
6440
6441 *** Article washing status can be displayed in the
6442 article mode line.
6443
6444 *** gnus.el has been split into many smaller files.
6445
6446 *** Suppression of duplicate articles based on Message-ID.
6447
6448 (setq gnus-suppress-duplicates t)
6449
6450 *** New variables for specifying what score and adapt files
6451 are to be considered home score and adapt files. See
6452 `gnus-home-score-file' and `gnus-home-adapt-files'.
6453
6454 *** Groups can inherit group parameters from parent topics.
6455
6456 *** Article editing has been revamped and is now usable.
6457
6458 *** Signatures can be recognized in more intelligent fashions.
6459 See `gnus-signature-separator' and `gnus-signature-limit'.
6460
6461 *** Summary pick mode has been made to look more nn-like.
6462 Line numbers are displayed and the `.' command can be
6463 used to pick articles.
6464
6465 *** Commands for moving the .newsrc.eld from one server to
6466 another have been added.
6467
6468 `M-x gnus-change-server'
6469
6470 *** A way to specify that "uninteresting" fields be suppressed when
6471 generating lines in buffers.
6472
6473 *** Several commands in the group buffer can be undone with
6474 `M-C-_'.
6475
6476 *** Scoring can be done on words using the new score type `w'.
6477
6478 *** Adaptive scoring can be done on a Subject word-by-word basis:
6479
6480 (setq gnus-use-adaptive-scoring '(word))
6481
6482 *** Scores can be decayed.
6483
6484 (setq gnus-decay-scores t)
6485
6486 *** Scoring can be performed using a regexp on the Date header. The
6487 Date is normalized to compact ISO 8601 format first.
6488
6489 *** A new command has been added to remove all data on articles from
6490 the native server.
6491
6492 `M-x gnus-group-clear-data-on-native-groups'
6493
6494 *** A new command for reading collections of documents
6495 (nndoc with nnvirtual on top) has been added -- `M-C-d'.
6496
6497 *** Process mark sets can be pushed and popped.
6498
6499 *** A new mail-to-news backend makes it possible to post
6500 even when the NNTP server doesn't allow posting.
6501
6502 *** A new backend for reading searches from Web search engines
6503 (DejaNews, Alta Vista, InReference) has been added.
6504
6505 Use the `G w' command in the group buffer to create such
6506 a group.
6507
6508 *** Groups inside topics can now be sorted using the standard
6509 sorting functions, and each topic can be sorted independently.
6510
6511 See the commands under the `T S' submap.
6512
6513 *** Subsets of the groups can be sorted independently.
6514
6515 See the commands under the `G P' submap.
6516
6517 *** Cached articles can be pulled into the groups.
6518
6519 Use the `Y c' command.
6520
6521 *** Score files are now applied in a more reliable order.
6522
6523 *** Reports on where mail messages end up can be generated.
6524
6525 `M-x nnmail-split-history'
6526
6527 *** More hooks and functions have been added to remove junk
6528 from incoming mail before saving the mail.
6529
6530 See `nnmail-prepare-incoming-header-hook'.
6531
6532 *** The nnml mail backend now understands compressed article files.
6533
6534 *** To enable Gnus to read/post multi-lingual articles, you must execute
6535 the following code, for instance, in your .emacs.
6536
6537 (add-hook 'gnus-startup-hook 'gnus-mule-initialize)
6538
6539 Then, when you start Gnus, it will decode non-ASCII text automatically
6540 and show appropriate characters. (Note: if you are using gnus-mime
6541 from the SEMI package, formerly known as TM, you should NOT add this
6542 hook to gnus-startup-hook; gnus-mime has its own method of handling
6543 this issue.)
6544
6545 Since it is impossible to distinguish all coding systems
6546 automatically, you may need to specify a choice of coding system for a
6547 particular news group. This can be done by:
6548
6549 (gnus-mule-add-group NEWSGROUP 'CODING-SYSTEM)
6550
6551 Here NEWSGROUP should be a string which names a newsgroup or a tree
6552 of newsgroups. If NEWSGROUP is "XXX.YYY", all news groups under
6553 "XXX.YYY" (including "XXX.YYY.ZZZ") will use the specified coding
6554 system. CODING-SYSTEM specifies which coding system to use (for both
6555 for reading and posting).
6556
6557 CODING-SYSTEM can also be a cons cell of the form
6558 (READ-CODING-SYSTEM . POST-CODING-SYSTEM)
6559 Then READ-CODING-SYSTEM is used when you read messages from the
6560 newsgroups, while POST-CODING-SYSTEM is used when you post messages
6561 there.
6562
6563 Emacs knows the right coding systems for certain newsgroups by
6564 default. Here are some of these default settings:
6565
6566 (gnus-mule-add-group "fj" 'iso-2022-7)
6567 (gnus-mule-add-group "alt.chinese.text" 'hz-gb-2312)
6568 (gnus-mule-add-group "alt.hk" 'hz-gb-2312)
6569 (gnus-mule-add-group "alt.chinese.text.big5" 'cn-big5)
6570 (gnus-mule-add-group "soc.culture.vietnamese" '(nil . viqr))
6571
6572 When you reply by mail to an article, these settings are ignored;
6573 the mail is encoded according to sendmail-coding-system, as usual.
6574
6575 ** CC mode changes.
6576
6577 *** If you edit primarily one style of C (or C++, Objective-C, Java)
6578 code, you may want to make the CC Mode style variables have global
6579 values so that you can set them directly in your .emacs file. To do
6580 this, set c-style-variables-are-local-p to nil in your .emacs file.
6581 Note that this only takes effect if you do it *before* cc-mode.el is
6582 loaded.
6583
6584 If you typically edit more than one style of C (or C++, Objective-C,
6585 Java) code in a single Emacs session, you may want to make the CC Mode
6586 style variables have buffer local values. By default, all buffers
6587 share the same style variable settings; to make them buffer local, set
6588 c-style-variables-are-local-p to t in your .emacs file. Note that you
6589 must do this *before* CC Mode is loaded.
6590
6591 *** The new variable c-indentation-style holds the C style name
6592 of the current buffer.
6593
6594 *** The variable c-block-comments-indent-p has been deleted, because
6595 it is no longer necessary. C mode now handles all the supported styles
6596 of block comments, with no need to say which one you will use.
6597
6598 *** There is a new indentation style "python", which specifies the C
6599 style that the Python developers like.
6600
6601 *** There is a new c-cleanup-list option: brace-elseif-brace.
6602 This says to put ...} else if (...) {... on one line,
6603 just as brace-else-brace says to put ...} else {... on one line.
6604
6605 ** VC Changes [new]
6606
6607 ** In vc-retrieve-snapshot (C-x v r), if you don't specify a snapshot
6608 name, it retrieves the *latest* versions of all files in the current
6609 directory and its subdirectories (aside from files already locked).
6610
6611 This feature is useful if your RCS directory is a link to a common
6612 master directory, and you want to pick up changes made by other
6613 developers.
6614
6615 You can do the same thing for an individual file by typing C-u C-x C-q
6616 RET in a buffer visiting that file.
6617
6618 *** VC can now handle files under CVS that are being "watched" by
6619 other developers. Such files are made read-only by CVS. To get a
6620 writable copy, type C-x C-q in a buffer visiting such a file. VC then
6621 calls "cvs edit", which notifies the other developers of it.
6622
6623 *** vc-version-diff (C-u C-x v =) now suggests reasonable defaults for
6624 version numbers, based on the current state of the file.
6625
6626 ** Calendar changes.
6627
6628 A new function, list-holidays, allows you list holidays or subclasses
6629 of holidays for ranges of years. Related menu items allow you do this
6630 for the year of the selected date, or the following/previous years.
6631
6632 ** ps-print changes
6633
6634 There are some new user variables for customizing the page layout.
6635
6636 *** Paper size, paper orientation, columns
6637
6638 The variable `ps-paper-type' determines the size of paper ps-print
6639 formats for; it should contain one of the symbols:
6640 `a4' `a3' `letter' `legal' `letter-small' `tabloid'
6641 `ledger' `statement' `executive' `a4small' `b4' `b5'
6642 It defaults to `letter'.
6643 If you need other sizes, see the variable `ps-page-dimensions-database'.
6644
6645 The variable `ps-landscape-mode' determines the orientation
6646 of the printing on the page. nil, the default, means "portrait" mode,
6647 non-nil means "landscape" mode.
6648
6649 The variable `ps-number-of-columns' must be a positive integer.
6650 It determines the number of columns both in landscape and portrait mode.
6651 It defaults to 1.
6652
6653 *** Horizontal layout
6654
6655 The horizontal layout is determined by the variables
6656 `ps-left-margin', `ps-inter-column', and `ps-right-margin'.
6657 All are measured in points.
6658
6659 *** Vertical layout
6660
6661 The vertical layout is determined by the variables
6662 `ps-bottom-margin', `ps-top-margin', and `ps-header-offset'.
6663 All are measured in points.
6664
6665 *** Headers
6666
6667 If the variable `ps-print-header' is nil, no header is printed. Then
6668 `ps-header-offset' is not relevant and `ps-top-margin' represents the
6669 margin above the text.
6670
6671 If the variable `ps-print-header-frame' is non-nil, a gaudy
6672 framing box is printed around the header.
6673
6674 The contents of the header are determined by `ps-header-lines',
6675 `ps-show-n-of-n', `ps-left-header' and `ps-right-header'.
6676
6677 The height of the header is determined by `ps-header-line-pad',
6678 `ps-header-font-family', `ps-header-title-font-size' and
6679 `ps-header-font-size'.
6680
6681 *** Font managing
6682
6683 The variable `ps-font-family' determines which font family is to be
6684 used for ordinary text. Its value must be a key symbol in the alist
6685 `ps-font-info-database'. You can add other font families by adding
6686 elements to this alist.
6687
6688 The variable `ps-font-size' determines the size of the font
6689 for ordinary text. It defaults to 8.5 points.
6690
6691 ** hideshow changes.
6692
6693 *** now supports hiding of blocks of single line comments (like // for
6694 C++, ; for lisp).
6695
6696 *** Support for java-mode added.
6697
6698 *** When doing `hs-hide-all' it is now possible to also hide the comments
6699 in the file if `hs-hide-comments-when-hiding-all' is set.
6700
6701 *** The new function `hs-hide-initial-comment' hides the the comments at
6702 the beginning of the files. Finally those huge RCS logs don't stay in your
6703 way! This is run by default when entering the `hs-minor-mode'.
6704
6705 *** Now uses overlays instead of `selective-display', so is more
6706 robust and a lot faster.
6707
6708 *** A block beginning can span multiple lines.
6709
6710 *** The new variable `hs-show-hidden-short-form' if t, directs hideshow
6711 to show only the beginning of a block when it is hidden. See the
6712 documentation for more details.
6713
6714 ** Changes in Enriched mode.
6715
6716 *** When you visit a file in enriched-mode, Emacs will make sure it is
6717 filled to the current fill-column. This behavior is now independent
6718 of the size of the window. When you save the file, the fill-column in
6719 use is stored as well, so that the whole buffer need not be refilled
6720 the next time unless the fill-column is different.
6721
6722 *** use-hard-newlines is now a minor mode. When it is enabled, Emacs
6723 distinguishes between hard and soft newlines, and treats hard newlines
6724 as paragraph boundaries. Otherwise all newlines inserted are marked
6725 as soft, and paragraph boundaries are determined solely from the text.
6726
6727 ** Font Lock mode
6728
6729 *** Custom support
6730
6731 The variables font-lock-face-attributes, font-lock-display-type and
6732 font-lock-background-mode are now obsolete; the recommended way to specify the
6733 faces to use for Font Lock mode is with M-x customize-group on the new custom
6734 group font-lock-highlighting-faces. If you set font-lock-face-attributes in
6735 your ~/.emacs file, Font Lock mode will respect its value. However, you should
6736 consider converting from setting that variable to using M-x customize.
6737
6738 You can still use X resources to specify Font Lock face appearances.
6739
6740 *** Maximum decoration
6741
6742 Fontification now uses the maximum level of decoration supported by
6743 default. Previously, fontification used a mode-specific default level
6744 of decoration, which is typically the minimum level of decoration
6745 supported. You can set font-lock-maximum-decoration to nil
6746 to get the old behavior.
6747
6748 *** New support
6749
6750 Support is now provided for Java, Objective-C, AWK and SIMULA modes.
6751
6752 Note that Font Lock mode can be turned on without knowing exactly what modes
6753 support Font Lock mode, via the command global-font-lock-mode.
6754
6755 *** Configurable support
6756
6757 Support for C, C++, Objective-C and Java can be more easily configured for
6758 additional types and classes via the new variables c-font-lock-extra-types,
6759 c++-font-lock-extra-types, objc-font-lock-extra-types and, you guessed it,
6760 java-font-lock-extra-types. These value of each of these variables should be a
6761 list of regexps matching the extra type names. For example, the default value
6762 of c-font-lock-extra-types is ("\\sw+_t") which means fontification follows the
6763 convention that C type names end in _t. This results in slower fontification.
6764
6765 Of course, you can change the variables that specify fontification in whatever
6766 way you wish, typically by adding regexps. However, these new variables make
6767 it easier to make specific and common changes for the fontification of types.
6768
6769 *** Adding highlighting patterns to existing support
6770
6771 You can use the new function font-lock-add-keywords to add your own
6772 highlighting patterns, such as for project-local or user-specific constructs,
6773 for any mode.
6774
6775 For example, to highlight `FIXME:' words in C comments, put:
6776
6777 (font-lock-add-keywords 'c-mode '(("\\<FIXME:" 0 font-lock-warning-face t)))
6778
6779 in your ~/.emacs.
6780
6781 *** New faces
6782
6783 Font Lock now defines two new faces, font-lock-builtin-face and
6784 font-lock-warning-face. These are intended to highlight builtin keywords,
6785 distinct from a language's normal keywords, and objects that should be brought
6786 to user attention, respectively. Various modes now use these new faces.
6787
6788 *** Changes to fast-lock support mode
6789
6790 The fast-lock package, one of the two Font Lock support modes, can now process
6791 cache files silently. You can use the new variable fast-lock-verbose, in the
6792 same way as font-lock-verbose, to control this feature.
6793
6794 *** Changes to lazy-lock support mode
6795
6796 The lazy-lock package, one of the two Font Lock support modes, can now fontify
6797 according to the true syntactic context relative to other lines. You can use
6798 the new variable lazy-lock-defer-contextually to control this feature. If
6799 non-nil, changes to the buffer will cause subsequent lines in the buffer to be
6800 refontified after lazy-lock-defer-time seconds of idle time. If nil, then only
6801 the modified lines will be refontified; this is the same as the previous Lazy
6802 Lock mode behaviour and the behaviour of Font Lock mode.
6803
6804 This feature is useful in modes where strings or comments can span lines.
6805 For example, if a string or comment terminating character is deleted, then if
6806 this feature is enabled subsequent lines in the buffer will be correctly
6807 refontified to reflect their new syntactic context. Previously, only the line
6808 containing the deleted character would be refontified and you would have to use
6809 the command M-g M-g (font-lock-fontify-block) to refontify some lines.
6810
6811 As a consequence of this new feature, two other variables have changed:
6812
6813 Variable `lazy-lock-defer-driven' is renamed `lazy-lock-defer-on-scrolling'.
6814 Variable `lazy-lock-defer-time' can now only be a time, i.e., a number.
6815 Buffer modes for which on-the-fly deferral applies can be specified via the
6816 new variable `lazy-lock-defer-on-the-fly'.
6817
6818 If you set these variables in your ~/.emacs, then you may have to change those
6819 settings.
6820
6821 ** Ada mode changes.
6822
6823 *** There is now better support for using find-file.el with Ada mode.
6824 If you switch between spec and body, the cursor stays in the same
6825 procedure (modulo overloading). If a spec has no body file yet, but
6826 you try to switch to its body file, Ada mode now generates procedure
6827 stubs.
6828
6829 *** There are two new commands:
6830 - `ada-make-local' : invokes gnatmake on the current buffer
6831 - `ada-check-syntax' : check syntax of current buffer.
6832
6833 The user options `ada-compiler-make', `ada-make-options',
6834 `ada-language-version', `ada-compiler-syntax-check', and
6835 `ada-compile-options' are used within these commands.
6836
6837 *** Ada mode can now work with Outline minor mode. The outline level
6838 is calculated from the indenting, not from syntactic constructs.
6839 Outlining does not work if your code is not correctly indented.
6840
6841 *** The new function `ada-gnat-style' converts the buffer to the style of
6842 formatting used in GNAT. It places two blanks after a comment start,
6843 places one blank between a word end and an opening '(', and puts one
6844 space between a comma and the beginning of a word.
6845
6846 ** Scheme mode changes.
6847
6848 *** Scheme mode indentation now uses many of the facilities of Lisp
6849 mode; therefore, the variables to customize it are the variables used
6850 for Lisp mode which have names starting with `lisp-'. The variables
6851 with names starting with `scheme-' which used to do this no longer
6852 have any effect.
6853
6854 If you want to use different indentation for Scheme and Lisp, this is
6855 still possible, but now you must do it by adding a hook to
6856 scheme-mode-hook, which could work by setting the `lisp-' indentation
6857 variables as buffer-local variables.
6858
6859 *** DSSSL mode is a variant of Scheme mode, for editing DSSSL scripts.
6860 Use M-x dsssl-mode.
6861
6862 ** Changes to the emacsclient program
6863
6864 *** If a socket can't be found, and environment variables LOGNAME or
6865 USER are set, emacsclient now looks for a socket based on the UID
6866 associated with the name. That is an emacsclient running as root
6867 can connect to an Emacs server started by a non-root user.
6868
6869 *** The emacsclient program now accepts an option --no-wait which tells
6870 it to return immediately without waiting for you to "finish" the
6871 buffer in Emacs.
6872
6873 *** The new option --alternate-editor allows to specify an editor to
6874 use if Emacs is not running. The environment variable
6875 ALTERNATE_EDITOR can be used for the same effect; the command line
6876 option takes precedence.
6877
6878 ** M-x eldoc-mode enables a minor mode in which the echo area
6879 constantly shows the parameter list for function being called at point
6880 (in Emacs Lisp and Lisp Interaction modes only).
6881
6882 ** C-x n d now runs the new command narrow-to-defun,
6883 which narrows the accessible parts of the buffer to just
6884 the current defun.
6885
6886 ** Emacs now handles the `--' argument in the standard way; all
6887 following arguments are treated as ordinary file names.
6888
6889 ** On MSDOS and Windows, the bookmark file is now called _emacs.bmk,
6890 and the saved desktop file is now called _emacs.desktop (truncated if
6891 necessary).
6892
6893 ** When you kill a buffer that visits a file,
6894 if there are any registers that save positions in the file,
6895 these register values no longer become completely useless.
6896 If you try to go to such a register with C-x j, then you are
6897 asked whether to visit the file again. If you say yes,
6898 it visits the file and then goes to the same position.
6899
6900 ** When you visit a file that changes frequently outside Emacs--for
6901 example, a log of output from a process that continues to run--it may
6902 be useful for Emacs to revert the file without querying you whenever
6903 you visit the file afresh with C-x C-f.
6904
6905 You can request this behavior for certain files by setting the
6906 variable revert-without-query to a list of regular expressions. If a
6907 file's name matches any of these regular expressions, find-file and
6908 revert-buffer revert the buffer without asking for permission--but
6909 only if you have not edited the buffer text yourself.
6910
6911 ** set-default-font has been renamed to set-frame-font
6912 since it applies only to the current frame.
6913
6914 ** In TeX mode, you can use the variable tex-main-file to specify the
6915 file for tex-file to run TeX on. (By default, tex-main-file is nil,
6916 and tex-file runs TeX on the current visited file.)
6917
6918 This is useful when you are editing a document that consists of
6919 multiple files. In each of the included files, you can set up a local
6920 variable list which specifies the top-level file of your document for
6921 tex-main-file. Then tex-file will run TeX on the whole document
6922 instead of just the file you are editing.
6923
6924 ** RefTeX mode
6925
6926 RefTeX mode is a new minor mode with special support for \label, \ref
6927 and \cite macros in LaTeX documents. RefTeX distinguishes labels of
6928 different environments (equation, figure, ...) and has full support for
6929 multifile documents. To use it, select a buffer with a LaTeX document and
6930 turn the mode on with M-x reftex-mode. Here are the main user commands:
6931
6932 C-c ( reftex-label
6933 Creates a label semi-automatically. RefTeX is context sensitive and
6934 knows which kind of label is needed.
6935
6936 C-c ) reftex-reference
6937 Offers in a menu all labels in the document, along with context of the
6938 label definition. The selected label is referenced as \ref{LABEL}.
6939
6940 C-c [ reftex-citation
6941 Prompts for a regular expression and displays a list of matching BibTeX
6942 database entries. The selected entry is cited with a \cite{KEY} macro.
6943
6944 C-c & reftex-view-crossref
6945 Views the cross reference of a \ref or \cite command near point.
6946
6947 C-c = reftex-toc
6948 Shows a table of contents of the (multifile) document. From there you
6949 can quickly jump to every section.
6950
6951 Under X, RefTeX installs a "Ref" menu in the menu bar, with additional
6952 commands. Press `?' to get help when a prompt mentions this feature.
6953 Full documentation and customization examples are in the file
6954 reftex.el. You can use the finder to view the file documentation:
6955 C-h p --> tex --> reftex.el
6956
6957 ** Changes in BibTeX mode.
6958
6959 *** Info documentation is now available.
6960
6961 *** Don't allow parentheses in string constants anymore. This confused
6962 both the BibTeX program and Emacs BibTeX mode.
6963
6964 *** Renamed variable bibtex-mode-user-optional-fields to
6965 bibtex-user-optional-fields.
6966
6967 *** Removed variable bibtex-include-OPTannote
6968 (use bibtex-user-optional-fields instead).
6969
6970 *** New interactive functions to copy and kill fields and complete
6971 entries to the BibTeX kill ring, from where they can be yanked back by
6972 appropriate functions.
6973
6974 *** New interactive functions for repositioning and marking of
6975 entries. They are bound by default to M-C-l and M-C-h.
6976
6977 *** New hook bibtex-clean-entry-hook. It is called after entry has
6978 been cleaned.
6979
6980 *** New variable bibtex-field-delimiters, which replaces variables
6981 bibtex-field-{left|right}-delimiter.
6982
6983 *** New variable bibtex-entry-delimiters to determine how entries
6984 shall be delimited.
6985
6986 *** Allow preinitialization of fields. See documentation of
6987 bibtex-user-optional-fields, bibtex-entry-field-alist, and
6988 bibtex-include-OPTkey for details.
6989
6990 *** Book and InBook entries require either an author or an editor
6991 field. This is now supported by bibtex.el. Alternative fields are
6992 prefixed with `ALT'.
6993
6994 *** New variable bibtex-entry-format, which replaces variable
6995 bibtex-clean-entry-zap-empty-opts and allows specification of many
6996 formatting options performed on cleaning an entry (see variable
6997 documentation).
6998
6999 *** Even more control on how automatic keys are generated. See
7000 documentation of bibtex-generate-autokey for details. Transcriptions
7001 for foreign languages other than German are now handled, too.
7002
7003 *** New boolean user option bibtex-comma-after-last-field to decide if
7004 comma should be inserted at end of last field.
7005
7006 *** New boolean user option bibtex-align-at-equal-sign to determine if
7007 alignment should be made at left side of field contents or at equal
7008 signs. New user options to control entry layout (e.g. indentation).
7009
7010 *** New function bibtex-fill-entry to realign entries.
7011
7012 *** New function bibtex-reformat to reformat region or buffer.
7013
7014 *** New function bibtex-convert-alien to convert a BibTeX database
7015 from alien sources.
7016
7017 *** New function bibtex-complete-key (similar to bibtex-complete-string)
7018 to complete prefix to a key defined in buffer. Mainly useful in
7019 crossref entries.
7020
7021 *** New function bibtex-count-entries to count entries in buffer or
7022 region.
7023
7024 *** Added support for imenu.
7025
7026 *** The function `bibtex-validate' now checks current region instead
7027 of buffer if mark is active. Now it shows all errors of buffer in a
7028 `compilation mode' buffer. You can use the normal commands (e.g.
7029 `next-error') for compilation modes to jump to errors.
7030
7031 *** New variable `bibtex-string-file-path' to determine where the files
7032 from `bibtex-string-files' are searched.
7033
7034 ** Iso Accents mode now supports Latin-3 as an alternative.
7035
7036 ** The command next-error now opens blocks hidden by hideshow.
7037
7038 ** The function using-unix-filesystems has been replaced by the
7039 functions add-untranslated-filesystem and remove-untranslated-filesystem.
7040 Each of these functions takes the name of a drive letter or directory
7041 as an argument.
7042
7043 When a filesystem is added as untranslated, all files on it are read
7044 and written in binary mode (no cr/lf translation is performed).
7045
7046 ** browse-url changes
7047
7048 *** New methods for: Grail (browse-url-generic), MMM (browse-url-mmm),
7049 Lynx in a separate xterm (browse-url-lynx-xterm) or in an Emacs window
7050 (browse-url-lynx-emacs), remote W3 (browse-url-w3-gnudoit), generic
7051 non-remote-controlled browsers (browse-url-generic) and associated
7052 customization variables.
7053
7054 *** New commands `browse-url-of-region' and `browse-url'.
7055
7056 *** URLs marked up with <URL:...> (RFC1738) work if broken across
7057 lines. Browsing methods can be associated with URL regexps
7058 (e.g. mailto: URLs) via `browse-url-browser-function'.
7059
7060 ** Changes in Ediff
7061
7062 *** Clicking Mouse-2 on a brief command description in Ediff control panel
7063 pops up the Info file for this command.
7064
7065 *** There is now a variable, ediff-autostore-merges, which controls whether
7066 the result of a merge is saved in a file. By default, this is done only when
7067 merge is done from a session group (eg, when merging files in two different
7068 directories).
7069
7070 *** Since Emacs 19.31 (this hasn't been announced before), Ediff can compare
7071 and merge groups of files residing in different directories, or revisions of
7072 files in the same directory.
7073
7074 *** Since Emacs 19.31, Ediff can apply multi-file patches interactively.
7075 The patches must be in the context format or GNU unified format. (The bug
7076 related to the GNU format has now been fixed.)
7077
7078 ** Changes in Viper
7079
7080 *** The startup file is now .viper instead of .vip
7081 *** All variable/function names have been changed to start with viper-
7082 instead of vip-.
7083 *** C-\ now simulates the meta-key in all Viper states.
7084 *** C-z in Insert state now escapes to Vi for the duration of the next
7085 Viper command. In Vi and Insert states, C-z behaves as before.
7086 *** C-c \ escapes to Vi for one command if Viper is in Insert or Emacs states.
7087 *** _ is no longer the meta-key in Vi state.
7088 *** The variable viper-insert-state-cursor-color can be used to change cursor
7089 color when Viper is in insert state.
7090 *** If search lands the cursor near the top or the bottom of the window,
7091 Viper pulls the window up or down to expose more context. The variable
7092 viper-adjust-window-after-search controls this behavior.
7093
7094 ** Etags changes.
7095
7096 *** In C, C++, Objective C and Java, Etags tags global variables by
7097 default. The resulting tags files are inflated by 30% on average.
7098 Use --no-globals to turn this feature off. Etags can also tag
7099 variables which are members of structure-like constructs, but it does
7100 not by default. Use --members to turn this feature on.
7101
7102 *** C++ member functions are now recognized as tags.
7103
7104 *** Java is tagged like C++. In addition, "extends" and "implements"
7105 constructs are tagged. Files are recognised by the extension .java.
7106
7107 *** Etags can now handle programs written in Postscript. Files are
7108 recognised by the extensions .ps and .pdb (Postscript with C syntax).
7109 In Postscript, tags are lines that start with a slash.
7110
7111 *** Etags now handles Objective C and Objective C++ code. The usual C and
7112 C++ tags are recognized in these languages; in addition, etags
7113 recognizes special Objective C syntax for classes, class categories,
7114 methods and protocols.
7115
7116 *** Etags also handles Cobol. Files are recognised by the extension
7117 .cobol. The tagged lines are those containing a word that begins in
7118 column 8 and ends in a full stop, i.e. anything that could be a
7119 paragraph name.
7120
7121 *** Regexps in Etags now support intervals, as in ed or grep. The syntax of
7122 an interval is \{M,N\}, and it means to match the preceding expression
7123 at least M times and as many as N times.
7124
7125 ** The format for specifying a custom format for time-stamp to insert
7126 in files has changed slightly.
7127
7128 With the new enhancements to the functionality of format-time-string,
7129 time-stamp-format will change to be eventually compatible with it.
7130 This conversion is being done in two steps to maintain compatibility
7131 with old time-stamp-format values.
7132
7133 In the new scheme, alternate case is signified by the number-sign
7134 (`#') modifier, rather than changing the case of the format character.
7135 This feature is as yet incompletely implemented for compatibility
7136 reasons.
7137
7138 In the old time-stamp-format, all numeric fields defaulted to their
7139 natural width. (With format-time-string, each format has a
7140 fixed-width default.) In this version, you can specify the colon
7141 (`:') modifier to a numeric conversion to mean "give me the historical
7142 time-stamp-format width default." Do not use colon if you are
7143 specifying an explicit width, as in "%02d".
7144
7145 Numbers are no longer truncated to the requested width, except in the
7146 case of "%02y", which continues to give a two-digit year. Digit
7147 truncation probably wasn't being used for anything else anyway.
7148
7149 The new formats will work with old versions of Emacs. New formats are
7150 being recommended now to allow time-stamp-format to change in the
7151 future to be compatible with format-time-string. The new forms being
7152 recommended now will continue to work then.
7153
7154 See the documentation string for the variable time-stamp-format for
7155 details.
7156
7157 ** There are some additional major modes:
7158
7159 dcl-mode, for editing VMS DCL files.
7160 m4-mode, for editing files of m4 input.
7161 meta-mode, for editing MetaFont and MetaPost source files.
7162
7163 ** In Shell mode, the command shell-copy-environment-variable lets you
7164 copy the value of a specified environment variable from the subshell
7165 into Emacs.
7166
7167 ** New Lisp packages include:
7168
7169 *** battery.el displays battery status for laptops.
7170
7171 *** M-x bruce (named after Lenny Bruce) is a program that might
7172 be used for adding some indecent words to your email.
7173
7174 *** M-x crisp-mode enables an emulation for the CRiSP editor.
7175
7176 *** M-x dirtrack arranges for better tracking of directory changes
7177 in shell buffers.
7178
7179 *** The new library elint.el provides for linting of Emacs Lisp code.
7180 See the documentation for `elint-initialize', `elint-current-buffer'
7181 and `elint-defun'.
7182
7183 *** M-x expand-add-abbrevs defines a special kind of abbrev which is
7184 meant for programming constructs. These abbrevs expand like ordinary
7185 ones, when you type SPC, but only at the end of a line and not within
7186 strings or comments.
7187
7188 These abbrevs can act as templates: you can define places within an
7189 abbrev for insertion of additional text. Once you expand the abbrev,
7190 you can then use C-x a p and C-x a n to move back and forth to these
7191 insertion points. Thus you can conveniently insert additional text
7192 at these points.
7193
7194 *** filecache.el remembers the location of files so that you
7195 can visit them by short forms of their names.
7196
7197 *** find-func.el lets you find the definition of the user-loaded
7198 Emacs Lisp function at point.
7199
7200 *** M-x handwrite converts text to a "handwritten" picture.
7201
7202 *** M-x iswitchb-buffer is a command for switching to a buffer, much like
7203 switch-buffer, but it reads the argument in a more helpful way.
7204
7205 *** M-x landmark implements a neural network for landmark learning.
7206
7207 *** M-x locate provides a convenient interface to the `locate' program.
7208
7209 *** M4 mode is a new mode for editing files of m4 input.
7210
7211 *** mantemp.el creates C++ manual template instantiations
7212 from the GCC error messages which indicate which instantiations are needed.
7213
7214 *** mouse-copy.el provides a one-click copy and move feature.
7215 You can drag a region with M-mouse-1, and it is automatically
7216 inserted at point. M-Shift-mouse-1 deletes the text from its
7217 original place after inserting the copy.
7218
7219 *** mouse-drag.el lets you do scrolling by dragging Mouse-2
7220 on the buffer.
7221
7222 You click the mouse and move; that distance either translates into the
7223 velocity to scroll (with mouse-drag-throw) or the distance to scroll
7224 (with mouse-drag-drag). Horizontal scrolling is enabled when needed.
7225
7226 Enable mouse-drag with:
7227 (global-set-key [down-mouse-2] 'mouse-drag-throw)
7228 -or-
7229 (global-set-key [down-mouse-2] 'mouse-drag-drag)
7230
7231 *** mspools.el is useful for determining which mail folders have
7232 mail waiting to be read in them. It works with procmail.
7233
7234 *** Octave mode is a major mode for editing files of input for Octave.
7235 It comes with a facility for communicating with an Octave subprocess.
7236
7237 *** ogonek
7238
7239 The ogonek package provides functions for changing the coding of
7240 Polish diacritic characters in buffers. Codings known from various
7241 platforms are supported such as ISO8859-2, Mazovia, IBM Latin2, and
7242 TeX. For example, you can change the coding from Mazovia to
7243 ISO8859-2. Another example is a change of coding from ISO8859-2 to
7244 prefix notation (in which `/a' stands for the aogonek character, for
7245 instance) and vice versa.
7246
7247 To use this package load it using
7248 M-x load-library [enter] ogonek
7249 Then, you may get an explanation by calling one of
7250 M-x ogonek-jak -- in Polish
7251 M-x ogonek-how -- in English
7252 The info specifies the commands and variables provided as well as the
7253 ways of customization in `.emacs'.
7254
7255 *** Interface to ph.
7256
7257 Emacs provides a client interface to CCSO Nameservers (ph/qi)
7258
7259 The CCSO nameserver is used in many universities to provide directory
7260 services about people. ph.el provides a convenient Emacs interface to
7261 these servers.
7262
7263 *** uce.el is useful for replying to unsolicited commercial email.
7264
7265 *** vcursor.el implements a "virtual cursor" feature.
7266 You can move the virtual cursor with special commands
7267 while the real cursor does not move.
7268
7269 *** webjump.el is a "hot list" package which you can set up
7270 for visiting your favorite web sites.
7271
7272 *** M-x winner-mode is a minor mode which saves window configurations,
7273 so you can move back to other configurations that you have recently used.
7274
7275 ** movemail change
7276
7277 Movemail no longer needs to be installed setuid root in order for POP
7278 mail retrieval to function properly. This is because it no longer
7279 supports the RPOP (reserved-port POP) protocol; instead, it uses the
7280 user's POP password to authenticate to the mail server.
7281
7282 This change was made earlier, but not reported in NEWS before.
7283 \f
7284 * Emacs 20.1 changes for MS-DOS and MS-Windows.
7285
7286 ** Changes in handling MS-DOS/MS-Windows text files.
7287
7288 Emacs handles three different conventions for representing
7289 end-of-line: CRLF for MSDOS, LF for Unix and GNU, and CR (used on the
7290 Macintosh). Emacs determines which convention is used in a specific
7291 file based on the contents of that file (except for certain special
7292 file names), and when it saves the file, it uses the same convention.
7293
7294 To save the file and change the end-of-line convention, you can use
7295 C-x RET f (set-buffer-file-coding-system) to specify a different
7296 coding system for the buffer. Then, when you save the file, the newly
7297 specified coding system will take effect. For example, to save with
7298 LF, specify undecided-unix (or some other ...-unix coding system); to
7299 save with CRLF, specify undecided-dos.
7300 \f
7301 * Lisp Changes in Emacs 20.1
7302
7303 ** Byte-compiled files made with Emacs 20 will, in general, work in
7304 Emacs 19 as well, as long as the source code runs in Emacs 19. And
7305 vice versa: byte-compiled files made with Emacs 19 should also run in
7306 Emacs 20, as long as the program itself works in Emacs 20.
7307
7308 ** Windows-specific functions and variables have been renamed
7309 to start with w32- instead of win32-.
7310
7311 In hacker language, calling something a "win" is a form of praise. We
7312 don't want to praise a non-free Microsoft system, so we don't call it
7313 "win".
7314
7315 ** Basic Lisp changes
7316
7317 *** A symbol whose name starts with a colon now automatically
7318 evaluates to itself. Therefore such a symbol can be used as a constant.
7319
7320 *** The defined purpose of `defconst' has been changed. It should now
7321 be used only for values that should not be changed whether by a program
7322 or by the user.
7323
7324 The actual behavior of defconst has not been changed.
7325
7326 *** There are new macros `when' and `unless'
7327
7328 (when CONDITION BODY...) is short for (if CONDITION (progn BODY...))
7329 (unless CONDITION BODY...) is short for (if CONDITION nil BODY...)
7330
7331 *** Emacs now defines functions caar, cadr, cdar and cddr with their
7332 usual Lisp meanings. For example, caar returns the car of the car of
7333 its argument.
7334
7335 *** equal, when comparing strings, now ignores their text properties.
7336
7337 *** The new function `functionp' tests whether an object is a function.
7338
7339 *** arrayp now returns t for char-tables and bool-vectors.
7340
7341 *** Certain primitives which use characters (as integers) now get an
7342 error if the integer is not a valid character code. These primitives
7343 include insert-char, char-to-string, and the %c construct in the
7344 `format' function.
7345
7346 *** The `require' function now insists on adding a suffix, either .el
7347 or .elc, to the file name. Thus, (require 'foo) will not use a file
7348 whose name is just foo. It insists on foo.el or foo.elc.
7349
7350 *** The `autoload' function, when the file name does not contain
7351 either a directory name or the suffix .el or .elc, insists on
7352 adding one of these suffixes.
7353
7354 *** string-to-number now takes an optional second argument BASE
7355 which specifies the base to use when converting an integer.
7356 If BASE is omitted, base 10 is used.
7357
7358 We have not implemented other radices for floating point numbers,
7359 because that would be much more work and does not seem useful.
7360
7361 *** substring now handles vectors as well as strings.
7362
7363 *** The Common Lisp function eql is no longer defined normally.
7364 You must load the `cl' library to define it.
7365
7366 *** The new macro `with-current-buffer' lets you evaluate an expression
7367 conveniently with a different current buffer. It looks like this:
7368
7369 (with-current-buffer BUFFER BODY-FORMS...)
7370
7371 BUFFER is the expression that says which buffer to use.
7372 BODY-FORMS say what to do in that buffer.
7373
7374 *** The new primitive `save-current-buffer' saves and restores the
7375 choice of current buffer, like `save-excursion', but without saving or
7376 restoring the value of point or the mark. `with-current-buffer'
7377 works using `save-current-buffer'.
7378
7379 *** The new macro `with-temp-file' lets you do some work in a new buffer and
7380 write the output to a specified file. Like `progn', it returns the value
7381 of the last form.
7382
7383 *** The new macro `with-temp-buffer' lets you do some work in a new buffer,
7384 which is discarded after use. Like `progn', it returns the value of the
7385 last form. If you wish to return the buffer contents, use (buffer-string)
7386 as the last form.
7387
7388 *** The new function split-string takes a string, splits it at certain
7389 characters, and returns a list of the substrings in between the
7390 matches.
7391
7392 For example, (split-string "foo bar lose" " +") returns ("foo" "bar" "lose").
7393
7394 *** The new macro with-output-to-string executes some Lisp expressions
7395 with standard-output set up so that all output feeds into a string.
7396 Then it returns that string.
7397
7398 For example, if the current buffer name is `foo',
7399
7400 (with-output-to-string
7401 (princ "The buffer is ")
7402 (princ (buffer-name)))
7403
7404 returns "The buffer is foo".
7405
7406 ** Non-ASCII characters are now supported, if enable-multibyte-characters
7407 is non-nil.
7408
7409 These characters have character codes above 256. When inserted in the
7410 buffer or stored in a string, they are represented as multibyte
7411 characters that occupy several buffer positions each.
7412
7413 *** When enable-multibyte-characters is non-nil, a single character in
7414 a buffer or string can be two or more bytes (as many as four).
7415
7416 Buffers and strings are still made up of unibyte elements;
7417 character positions and string indices are always measured in bytes.
7418 Therefore, moving forward one character can increase the buffer
7419 position by 2, 3 or 4. The function forward-char moves by whole
7420 characters, and therefore is no longer equivalent to
7421 (lambda (n) (goto-char (+ (point) n))).
7422
7423 ASCII characters (codes 0 through 127) are still single bytes, always.
7424 Sequences of byte values 128 through 255 are used to represent
7425 non-ASCII characters. These sequences are called "multibyte
7426 characters".
7427
7428 The first byte of a multibyte character is always in the range 128
7429 through 159 (octal 0200 through 0237). These values are called
7430 "leading codes". The second and subsequent bytes are always in the
7431 range 160 through 255 (octal 0240 through 0377). The first byte, the
7432 leading code, determines how many bytes long the sequence is.
7433
7434 *** The function forward-char moves over characters, and therefore
7435 (forward-char 1) may increase point by more than 1 if it moves over a
7436 multibyte character. Likewise, delete-char always deletes a
7437 character, which may be more than one buffer position.
7438
7439 This means that some Lisp programs, which assume that a character is
7440 always one buffer position, need to be changed.
7441
7442 However, all ASCII characters are always one buffer position.
7443
7444 *** The regexp [\200-\377] no longer matches all non-ASCII characters,
7445 because when enable-multibyte-characters is non-nil, these characters
7446 have codes that are not in the range octal 200 to octal 377. However,
7447 the regexp [^\000-\177] does match all non-ASCII characters,
7448 guaranteed.
7449
7450 *** The function char-boundary-p returns non-nil if position POS is
7451 between two characters in the buffer (not in the middle of a
7452 character).
7453
7454 When the value is non-nil, it says what kind of character follows POS:
7455
7456 0 if POS is at an ASCII character or at the end of range,
7457 1 if POS is before a 2-byte length multi-byte form,
7458 2 if POS is at a head of 3-byte length multi-byte form,
7459 3 if POS is at a head of 4-byte length multi-byte form,
7460 4 if POS is at a head of multi-byte form of a composite character.
7461
7462 *** The function char-bytes returns how many bytes the character CHAR uses.
7463
7464 *** Strings can contain multibyte characters. The function
7465 `length' returns the string length counting bytes, which may be
7466 more than the number of characters.
7467
7468 You can include a multibyte character in a string constant by writing
7469 it literally. You can also represent it with a hex escape,
7470 \xNNNNNNN..., using as many digits as necessary. Any character which
7471 is not a valid hex digit terminates this construct. If you want to
7472 follow it with a character that is a hex digit, write backslash and
7473 newline in between; that will terminate the hex escape.
7474
7475 *** The function concat-chars takes arguments which are characters
7476 and returns a string containing those characters.
7477
7478 *** The function sref access a multibyte character in a string.
7479 (sref STRING INDX) returns the character in STRING at INDEX. INDEX
7480 counts from zero. If INDEX is at a position in the middle of a
7481 character, sref signals an error.
7482
7483 *** The function chars-in-string returns the number of characters
7484 in a string. This is less than the length of the string, if the
7485 string contains multibyte characters (the length counts bytes).
7486
7487 *** The function chars-in-region returns the number of characters
7488 in a region from BEG to END. This is less than (- END BEG) if the
7489 region contains multibyte characters (the length counts bytes).
7490
7491 *** The function string-to-list converts a string to a list of
7492 the characters in it. string-to-vector converts a string
7493 to a vector of the characters in it.
7494
7495 *** The function store-substring alters part of the contents
7496 of a string. You call it as follows:
7497
7498 (store-substring STRING IDX OBJ)
7499
7500 This says to alter STRING, by storing OBJ starting at index IDX in
7501 STRING. OBJ may be either a character or a (smaller) string.
7502 This function really does alter the contents of STRING.
7503 Since it is impossible to change the length of an existing string,
7504 it is an error if OBJ doesn't fit within STRING's actual length.
7505
7506 *** char-width returns the width (in columns) of the character CHAR,
7507 if it were displayed in the current buffer and the selected window.
7508
7509 *** string-width returns the width (in columns) of the text in STRING,
7510 if it were displayed in the current buffer and the selected window.
7511
7512 *** truncate-string-to-width shortens a string, if necessary,
7513 to fit within a certain number of columns. (Of course, it does
7514 not alter the string that you give it; it returns a new string
7515 which contains all or just part of the existing string.)
7516
7517 (truncate-string-to-width STR END-COLUMN &optional START-COLUMN PADDING)
7518
7519 This returns the part of STR up to column END-COLUMN.
7520
7521 The optional argument START-COLUMN specifies the starting column.
7522 If this is non-nil, then the first START-COLUMN columns of the string
7523 are not included in the resulting value.
7524
7525 The optional argument PADDING, if non-nil, is a padding character to be added
7526 at the beginning and end the resulting string, to extend it to exactly
7527 WIDTH columns. If PADDING is nil, that means do not pad; then, if STRING
7528 is narrower than WIDTH, the value is equal to STRING.
7529
7530 If PADDING and START-COLUMN are both non-nil, and if there is no clean
7531 place in STRING that corresponds to START-COLUMN (because one
7532 character extends across that column), then the padding character
7533 PADDING is added one or more times at the beginning of the result
7534 string, so that its columns line up as if it really did start at
7535 column START-COLUMN.
7536
7537 *** When the functions in the list after-change-functions are called,
7538 the third argument is the number of bytes in the pre-change text, not
7539 necessarily the number of characters. It is, in effect, the
7540 difference in buffer position between the beginning and the end of the
7541 changed text, before the change.
7542
7543 *** The characters Emacs uses are classified in various character
7544 sets, each of which has a name which is a symbol. In general there is
7545 one character set for each script, not for each language.
7546
7547 **** The function charsetp tests whether an object is a character set name.
7548
7549 **** The variable charset-list holds a list of character set names.
7550
7551 **** char-charset, given a character code, returns the name of the character
7552 set that the character belongs to. (The value is a symbol.)
7553
7554 **** split-char, given a character code, returns a list containing the
7555 name of the character set, followed by one or two byte-values
7556 which identify the character within that character set.
7557
7558 **** make-char, given a character set name and one or two subsequent
7559 byte-values, constructs a character code. This is roughly the
7560 opposite of split-char.
7561
7562 **** find-charset-region returns a list of the character sets
7563 of all the characters between BEG and END.
7564
7565 **** find-charset-string returns a list of the character sets
7566 of all the characters in a string.
7567
7568 *** Here are the Lisp facilities for working with coding systems
7569 and specifying coding systems.
7570
7571 **** The function coding-system-list returns a list of all coding
7572 system names (symbols). With optional argument t, it returns a list
7573 of all distinct base coding systems, not including variants.
7574 (Variant coding systems are those like latin-1-dos, latin-1-unix
7575 and latin-1-mac which specify the end-of-line conversion as well
7576 as what to do about code conversion.)
7577
7578 **** coding-system-p tests a symbol to see if it is a coding system
7579 name. It returns t if so, nil if not.
7580
7581 **** file-coding-system-alist specifies which coding systems to use
7582 for certain file names. It works like network-coding-system-alist,
7583 except that the PATTERN is matched against the file name.
7584
7585 Each element has the format (PATTERN . VAL), where PATTERN determines
7586 which file names the element applies to. PATTERN should be a regexp
7587 to match against a file name.
7588
7589 VAL is a coding system, a cons cell containing two coding systems, or
7590 a function symbol. If VAL is a coding system, it is used for both
7591 decoding what received from the network stream and encoding what sent
7592 to the network stream. If VAL is a cons cell containing two coding
7593 systems, the car specifies the coding system for decoding, and the cdr
7594 specifies the coding system for encoding.
7595
7596 If VAL is a function symbol, the function must return a coding system
7597 or a cons cell containing two coding systems, which is used as above.
7598
7599 **** The variable network-coding-system-alist specifies
7600 the coding system to use for network sockets.
7601
7602 Each element has the format (PATTERN . VAL), where PATTERN determines
7603 which network sockets the element applies to. PATTERN should be
7604 either a port number or a regular expression matching some network
7605 service names.
7606
7607 VAL is a coding system, a cons cell containing two coding systems, or
7608 a function symbol. If VAL is a coding system, it is used for both
7609 decoding what received from the network stream and encoding what sent
7610 to the network stream. If VAL is a cons cell containing two coding
7611 systems, the car specifies the coding system for decoding, and the cdr
7612 specifies the coding system for encoding.
7613
7614 If VAL is a function symbol, the function must return a coding system
7615 or a cons cell containing two coding systems, which is used as above.
7616
7617 **** process-coding-system-alist specifies which coding systems to use
7618 for certain subprocess. It works like network-coding-system-alist,
7619 except that the PATTERN is matched against the program name used to
7620 start the subprocess.
7621
7622 **** The variable default-process-coding-system specifies the coding
7623 systems to use for subprocess (and net connection) input and output,
7624 when nothing else specifies what to do. The value is a cons cell
7625 (OUTPUT-CODING . INPUT-CODING). OUTPUT-CODING applies to output
7626 to the subprocess, and INPUT-CODING applies to input from it.
7627
7628 **** The variable coding-system-for-write, if non-nil, specifies the
7629 coding system to use for writing a file, or for output to a synchronous
7630 subprocess.
7631
7632 It also applies to any asynchronous subprocess or network connection,
7633 but in a different way: the value of coding-system-for-write when you
7634 start the subprocess or connection affects that subprocess or
7635 connection permanently or until overridden.
7636
7637 The variable coding-system-for-write takes precedence over
7638 file-coding-system-alist, process-coding-system-alist and
7639 network-coding-system-alist, and all other methods of specifying a
7640 coding system for output. But most of the time this variable is nil.
7641 It exists so that Lisp programs can bind it to a specific coding
7642 system for one operation at a time.
7643
7644 **** coding-system-for-read applies similarly to input from
7645 files, subprocesses or network connections.
7646
7647 **** The function process-coding-system tells you what
7648 coding systems(s) an existing subprocess is using.
7649 The value is a cons cell,
7650 (DECODING-CODING-SYSTEM . ENCODING-CODING-SYSTEM)
7651 where DECODING-CODING-SYSTEM is used for decoding output from
7652 the subprocess, and ENCODING-CODING-SYSTEM is used for encoding
7653 input to the subprocess.
7654
7655 **** The function set-process-coding-system can be used to
7656 change the coding systems in use for an existing subprocess.
7657
7658 ** Emacs has a new facility to help users manage the many
7659 customization options. To make a Lisp program work with this facility,
7660 you need to use the new macros defgroup and defcustom.
7661
7662 You use defcustom instead of defvar, for defining a user option
7663 variable. The difference is that you specify two additional pieces of
7664 information (usually): the "type" which says what values are
7665 legitimate, and the "group" which specifies the hierarchy for
7666 customization.
7667
7668 Thus, instead of writing
7669
7670 (defvar foo-blurgoze nil
7671 "*Non-nil means that foo will act very blurgozely.")
7672
7673 you would now write this:
7674
7675 (defcustom foo-blurgoze nil
7676 "*Non-nil means that foo will act very blurgozely."
7677 :type 'boolean
7678 :group foo)
7679
7680 The type `boolean' means that this variable has only
7681 two meaningful states: nil and non-nil. Other type values
7682 describe other possibilities; see the manual for Custom
7683 for a description of them.
7684
7685 The "group" argument is used to specify a group which the option
7686 should belong to. You define a new group like this:
7687
7688 (defgroup ispell nil
7689 "Spell checking using Ispell."
7690 :group 'processes)
7691
7692 The "group" argument in defgroup specifies the parent group. The root
7693 group is called `emacs'; it should not contain any variables itself,
7694 but only other groups. The immediate subgroups of `emacs' correspond
7695 to the keywords used by C-h p. Under these subgroups come
7696 second-level subgroups that belong to individual packages.
7697
7698 Each Emacs package should have its own set of groups. A simple
7699 package should have just one group; a more complex package should
7700 have a hierarchy of its own groups. The sole or root group of a
7701 package should be a subgroup of one or more of the "keyword"
7702 first-level subgroups.
7703
7704 ** New `widget' library for inserting UI components in buffers.
7705
7706 This library, used by the new custom library, is documented in a
7707 separate manual that accompanies Emacs.
7708
7709 ** easy-mmode
7710
7711 The easy-mmode package provides macros and functions that make
7712 developing minor modes easier. Roughly, the programmer has to code
7713 only the functionality of the minor mode. All the rest--toggles,
7714 predicate, and documentation--can be done in one call to the macro
7715 `easy-mmode-define-minor-mode' (see the documentation). See also
7716 `easy-mmode-define-keymap'.
7717
7718 ** Text property changes
7719
7720 *** The `intangible' property now works on overlays as well as on a
7721 text property.
7722
7723 *** The new functions next-char-property-change and
7724 previous-char-property-change scan through the buffer looking for a
7725 place where either a text property or an overlay might change. The
7726 functions take two arguments, POSITION and LIMIT. POSITION is the
7727 starting position for the scan. LIMIT says where to stop the scan.
7728
7729 If no property change is found before LIMIT, the value is LIMIT. If
7730 LIMIT is nil, scan goes to the beginning or end of the accessible part
7731 of the buffer. If no property change is found, the value is the
7732 position of the beginning or end of the buffer.
7733
7734 *** In the `local-map' text property or overlay property, the property
7735 value can now be a symbol whose function definition is a keymap. This
7736 is an alternative to using the keymap itself.
7737
7738 ** Changes in invisibility features
7739
7740 *** Isearch can now temporarily show parts of the buffer which are
7741 hidden by an overlay with a invisible property, when the search match
7742 is inside that portion of the buffer. To enable this the overlay
7743 should have a isearch-open-invisible property which is a function that
7744 would be called having the overlay as an argument, the function should
7745 make the overlay visible.
7746
7747 During incremental search the overlays are shown by modifying the
7748 invisible and intangible properties, if beside this more actions are
7749 needed the overlay should have a isearch-open-invisible-temporary
7750 which is a function. The function is called with 2 arguments: one is
7751 the overlay and the second is nil when it should show the overlay and
7752 t when it should hide it.
7753
7754 *** add-to-invisibility-spec, remove-from-invisibility-spec
7755
7756 Modes that use overlays to hide portions of a buffer should set the
7757 invisible property of the overlay to the mode's name (or another symbol)
7758 and modify the `buffer-invisibility-spec' to include that symbol.
7759 Use `add-to-invisibility-spec' and `remove-from-invisibility-spec' to
7760 manipulate the `buffer-invisibility-spec'.
7761 Here is an example of how to do this:
7762
7763 ;; If we want to display an ellipsis:
7764 (add-to-invisibility-spec '(my-symbol . t))
7765 ;; If you don't want ellipsis:
7766 (add-to-invisibility-spec 'my-symbol)
7767
7768 ...
7769 (overlay-put (make-overlay beginning end) 'invisible 'my-symbol)
7770
7771 ...
7772 ;; When done with the overlays:
7773 (remove-from-invisibility-spec '(my-symbol . t))
7774 ;; Or respectively:
7775 (remove-from-invisibility-spec 'my-symbol)
7776
7777 ** Changes in syntax parsing.
7778
7779 *** The syntax-directed buffer-scan functions (such as
7780 `parse-partial-sexp', `forward-word' and similar functions) can now
7781 obey syntax information specified by text properties, if the variable
7782 `parse-sexp-lookup-properties' is non-nil.
7783
7784 If the value of `parse-sexp-lookup-properties' is nil, the behavior
7785 is as before: the syntax-table of the current buffer is always
7786 used to determine the syntax of the character at the position.
7787
7788 When `parse-sexp-lookup-properties' is non-nil, the syntax of a
7789 character in the buffer is calculated thus:
7790
7791 a) if the `syntax-table' text-property of that character
7792 is a cons, this cons becomes the syntax-type;
7793
7794 Valid values of `syntax-table' text-property are: nil, a valid
7795 syntax-table, and a valid syntax-table element, i.e.,
7796 a cons cell of the form (SYNTAX-CODE . MATCHING-CHAR).
7797
7798 b) if the character's `syntax-table' text-property
7799 is a syntax table, this syntax table is used
7800 (instead of the syntax-table of the current buffer) to
7801 determine the syntax type of the character.
7802
7803 c) otherwise the syntax-type is determined by the syntax-table
7804 of the current buffer.
7805
7806 *** The meaning of \s in regular expressions is also affected by the
7807 value of `parse-sexp-lookup-properties'. The details are the same as
7808 for the syntax-directed buffer-scan functions.
7809
7810 *** There are two new syntax-codes, `!' and `|' (numeric values 14
7811 and 15). A character with a code `!' starts a comment which is ended
7812 only by another character with the same code (unless quoted). A
7813 character with a code `|' starts a string which is ended only by
7814 another character with the same code (unless quoted).
7815
7816 These codes are mainly meant for use as values of the `syntax-table'
7817 text property.
7818
7819 *** The function `parse-partial-sexp' has new semantics for the sixth
7820 arg COMMENTSTOP. If it is `syntax-table', parse stops after the start
7821 of a comment or a string, or after end of a comment or a string.
7822
7823 *** The state-list which the return value from `parse-partial-sexp'
7824 (and can also be used as an argument) now has an optional ninth
7825 element: the character address of the start of last comment or string;
7826 nil if none. The fourth and eighth elements have special values if the
7827 string/comment is started by a "!" or "|" syntax-code.
7828
7829 *** Since new features of `parse-partial-sexp' allow a complete
7830 syntactic parsing, `font-lock' no longer supports
7831 `font-lock-comment-start-regexp'.
7832
7833 ** Changes in face features
7834
7835 *** The face functions are now unconditionally defined in Emacs, even
7836 if it does not support displaying on a device that supports faces.
7837
7838 *** The function face-documentation returns the documentation string
7839 of a face (or nil if it doesn't have one).
7840
7841 *** The function face-bold-p returns t if a face should be bold.
7842 set-face-bold-p sets that flag.
7843
7844 *** The function face-italic-p returns t if a face should be italic.
7845 set-face-italic-p sets that flag.
7846
7847 *** You can now specify foreground and background colors for text
7848 by adding elements of the form (foreground-color . COLOR-NAME)
7849 and (background-color . COLOR-NAME) to the list of faces in
7850 the `face' property (either the character's text property or an
7851 overlay property).
7852
7853 This means that you no longer need to create named faces to use
7854 arbitrary colors in a Lisp package.
7855
7856 ** Changes in file-handling functions
7857
7858 *** File-access primitive functions no longer discard an extra redundant
7859 directory name from the beginning of the file name. In other words,
7860 they no longer do anything special with // or /~. That conversion
7861 is now done only in substitute-in-file-name.
7862
7863 This makes it possible for a Lisp program to open a file whose name
7864 begins with ~.
7865
7866 *** If copy-file is unable to set the date of the output file,
7867 it now signals an error with the condition file-date-error.
7868
7869 *** The inode number returned by file-attributes may be an integer (if
7870 the number fits in a Lisp integer) or a list of integers.
7871
7872 *** insert-file-contents can now read from a special file,
7873 as long as the arguments VISIT and REPLACE are nil.
7874
7875 *** The RAWFILE arg to find-file-noselect, if non-nil, now suppresses
7876 character code conversion as well as other things.
7877
7878 Meanwhile, this feature does work with remote file names
7879 (formerly it did not).
7880
7881 *** Lisp packages which create temporary files should use the TMPDIR
7882 environment variable to decide which directory to put them in.
7883
7884 *** interpreter-mode-alist elements now specify regexps
7885 instead of constant strings.
7886
7887 *** expand-file-name no longer treats `//' or `/~' specially. It used
7888 to delete all the text of a file name up through the first slash of
7889 any `//' or `/~' sequence. Now it passes them straight through.
7890
7891 substitute-in-file-name continues to treat those sequences specially,
7892 in the same way as before.
7893
7894 *** The variable `format-alist' is more general now.
7895 The FROM-FN and TO-FN in a format definition can now be strings
7896 which specify shell commands to use as filters to perform conversion.
7897
7898 *** The new function access-file tries to open a file, and signals an
7899 error if that fails. If the open succeeds, access-file does nothing
7900 else, and returns nil.
7901
7902 *** The function insert-directory now signals an error if the specified
7903 directory cannot be listed.
7904
7905 ** Changes in minibuffer input
7906
7907 *** The functions read-buffer, read-variable, read-command, read-string
7908 read-file-name, read-from-minibuffer and completing-read now take an
7909 additional argument which specifies the default value. If this
7910 argument is non-nil, it should be a string; that string is used in two
7911 ways:
7912
7913 It is returned if the user enters empty input.
7914 It is available through the history command M-n.
7915
7916 *** The functions read-string, read-from-minibuffer,
7917 read-no-blanks-input and completing-read now take an additional
7918 argument INHERIT-INPUT-METHOD. If this is non-nil, then the
7919 minibuffer inherits the current input method and the setting of
7920 enable-multibyte-characters from the previously current buffer.
7921
7922 In an interactive spec, you can use M instead of s to read an
7923 argument in this way.
7924
7925 *** All minibuffer input functions discard text properties
7926 from the text you enter in the minibuffer, unless the variable
7927 minibuffer-allow-text-properties is non-nil.
7928
7929 ** Echo area features
7930
7931 *** Clearing the echo area now runs the normal hook
7932 echo-area-clear-hook. Note that the echo area can be used while the
7933 minibuffer is active; in that case, the minibuffer is still active
7934 after the echo area is cleared.
7935
7936 *** The function current-message returns the message currently displayed
7937 in the echo area, or nil if there is none.
7938
7939 ** Keyboard input features
7940
7941 *** tty-erase-char is a new variable that reports which character was
7942 set up as the terminal's erase character when time Emacs was started.
7943
7944 *** num-nonmacro-input-events is the total number of input events
7945 received so far from the terminal. It does not count those generated
7946 by keyboard macros.
7947
7948 ** Frame-related changes
7949
7950 *** make-frame runs the normal hook before-make-frame-hook just before
7951 creating a frame, and just after creating a frame it runs the abnormal
7952 hook after-make-frame-functions with the new frame as arg.
7953
7954 *** The new hook window-configuration-change-hook is now run every time
7955 the window configuration has changed. The frame whose configuration
7956 has changed is the selected frame when the hook is run.
7957
7958 *** Each frame now independently records the order for recently
7959 selected buffers, in its buffer-list frame parameter, so that the
7960 value of other-buffer is now based on the buffers recently displayed
7961 in the selected frame.
7962
7963 *** The value of the frame parameter vertical-scroll-bars
7964 is now `left', `right' or nil. A non-nil value specifies
7965 which side of the window to put the scroll bars on.
7966
7967 ** X Windows features
7968
7969 *** You can examine X resources for other applications by binding
7970 x-resource-class around a call to x-get-resource. The usual value of
7971 x-resource-class is "Emacs", which is the correct value for Emacs.
7972
7973 *** In menus, checkboxes and radio buttons now actually work.
7974 The menu displays the current status of the box or button.
7975
7976 *** The function x-list-fonts now takes an optional fourth argument
7977 MAXIMUM which sets a limit on how many matching fonts to return.
7978 A smaller value of MAXIMUM makes the function faster.
7979
7980 If the only question is whether *any* font matches the pattern,
7981 it is good to supply 1 for this argument.
7982
7983 ** Subprocess features
7984
7985 *** A reminder: it is no longer necessary for subprocess filter
7986 functions and sentinels to do save-match-data, because Emacs does this
7987 automatically.
7988
7989 *** The new function shell-command-to-string executes a shell command
7990 and returns the output from the command as a string.
7991
7992 *** The new function process-contact returns t for a child process,
7993 and (HOSTNAME SERVICE) for a net connection.
7994
7995 ** An error in running pre-command-hook or post-command-hook
7996 does clear the variable to nil. The documentation was wrong before.
7997
7998 ** In define-key-after, if AFTER is t, the new binding now always goes
7999 at the end of the keymap. If the keymap is a menu, this means it
8000 goes after the other menu items.
8001
8002 ** If you have a program that makes several changes in the same area
8003 of the buffer, you can use the macro combine-after-change-calls
8004 around that Lisp code to make it faster when after-change hooks
8005 are in use.
8006
8007 The macro arranges to call the after-change functions just once for a
8008 series of several changes--if that seems safe.
8009
8010 Don't alter the variables after-change-functions and
8011 after-change-function within the body of a combine-after-change-calls
8012 form.
8013
8014 ** If you define an abbrev (with define-abbrev) whose EXPANSION
8015 is not a string, then the abbrev does not expand in the usual sense,
8016 but its hook is still run.
8017
8018 ** Normally, the Lisp debugger is not used (even if you have enabled it)
8019 for errors that are handled by condition-case.
8020
8021 If you set debug-on-signal to a non-nil value, then the debugger is called
8022 regardless of whether there is a handler for the condition. This is
8023 useful for debugging problems that happen inside of a condition-case.
8024
8025 This mode of operation seems to be unreliable in other ways. Errors that
8026 are normal and ought to be handled, perhaps in timers or process
8027 filters, will instead invoke the debugger. So don't say you weren't
8028 warned.
8029
8030 ** The new variable ring-bell-function lets you specify your own
8031 way for Emacs to "ring the bell".
8032
8033 ** If run-at-time's TIME argument is t, the action is repeated at
8034 integral multiples of REPEAT from the epoch; this is useful for
8035 functions like display-time.
8036
8037 ** You can use the function locate-library to find the precise file
8038 name of a Lisp library. This isn't new, but wasn't documented before.
8039
8040 ** Commands for entering view mode have new optional arguments that
8041 can be used from Lisp. Low-level entrance to and exit from view mode
8042 is done by functions view-mode-enter and view-mode-exit.
8043
8044 ** batch-byte-compile-file now makes Emacs return a nonzero status code
8045 if there is an error in compilation.
8046
8047 ** pop-to-buffer, switch-to-buffer-other-window and
8048 switch-to-buffer-other-frame now accept an additional optional
8049 argument NORECORD, much like switch-to-buffer. If it is non-nil,
8050 they don't put the buffer at the front of the buffer list.
8051
8052 ** If your .emacs file leaves the *scratch* buffer non-empty,
8053 Emacs does not display the startup message, so as to avoid changing
8054 the *scratch* buffer.
8055
8056 ** The new function regexp-opt returns an efficient regexp to match a string.
8057 The arguments are STRINGS and (optionally) PAREN. This function can be used
8058 where regexp matching or searching is intensively used and speed is important,
8059 e.g., in Font Lock mode.
8060
8061 ** The variable buffer-display-count is local to each buffer,
8062 and is incremented each time the buffer is displayed in a window.
8063 It starts at 0 when the buffer is created.
8064
8065 ** The new function compose-mail starts composing a mail message
8066 using the user's chosen mail composition agent (specified with the
8067 variable mail-user-agent). It has variants compose-mail-other-window
8068 and compose-mail-other-frame.
8069
8070 ** The `user-full-name' function now takes an optional parameter which
8071 can either be a number (the UID) or a string (the login name). The
8072 full name of the specified user will be returned.
8073
8074 ** Lisp packages that load files of customizations, or any other sort
8075 of user profile, should obey the variable init-file-user in deciding
8076 where to find it. They should load the profile of the user name found
8077 in that variable. If init-file-user is nil, meaning that the -q
8078 option was used, then Lisp packages should not load the customization
8079 files at all.
8080
8081 ** format-time-string now allows you to specify the field width
8082 and type of padding. This works as in printf: you write the field
8083 width as digits in the middle of a %-construct. If you start
8084 the field width with 0, it means to pad with zeros.
8085
8086 For example, %S normally specifies the number of seconds since the
8087 minute; %03S means to pad this with zeros to 3 positions, %_3S to pad
8088 with spaces to 3 positions. Plain %3S pads with zeros, because that
8089 is how %S normally pads to two positions.
8090
8091 ** thing-at-point now supports a new kind of "thing": url.
8092
8093 ** imenu.el changes.
8094
8095 You can now specify a function to be run when selecting an
8096 item from menu created by imenu.
8097
8098 An example of using this feature: if we define imenu items for the
8099 #include directives in a C file, we can open the included file when we
8100 select one of those items.
8101 \f
8102 * Emacs 19.34 is a bug-fix release with no user-visible changes.
8103 \f
8104 * Changes in Emacs 19.33.
8105
8106 ** Bibtex mode no longer turns on Auto Fill automatically. (No major
8107 mode should do that--it is the user's choice.)
8108
8109 ** The variable normal-auto-fill-function specifies the function to
8110 use for auto-fill-function, if and when Auto Fill is turned on.
8111 Major modes can set this locally to alter how Auto Fill works.
8112 \f
8113 * Editing Changes in Emacs 19.32
8114
8115 ** C-x f with no argument now signals an error.
8116 To set the fill column at the current column, use C-u C-x f.
8117
8118 ** Expanding dynamic abbrevs with M-/ is now smarter about case
8119 conversion. If you type the abbreviation with mixed case, and it
8120 matches the beginning of the expansion including case, then the
8121 expansion is copied verbatim. Using SPC M-/ to copy an additional
8122 word always copies it verbatim except when the previous copied word is
8123 all caps.
8124
8125 ** On a non-windowing terminal, which can display only one Emacs frame
8126 at a time, creating a new frame with C-x 5 2 also selects that frame.
8127
8128 When using a display that can show multiple frames at once, C-x 5 2
8129 does make the frame visible, but does not select it. This is the same
8130 as in previous Emacs versions.
8131
8132 ** You can use C-x 5 2 to create multiple frames on MSDOS, just as on a
8133 non-X terminal on Unix. Of course, only one frame is visible at any
8134 time, since your terminal doesn't have the ability to display multiple
8135 frames.
8136
8137 ** On Windows, set win32-pass-alt-to-system to a non-nil value
8138 if you would like tapping the Alt key to invoke the Windows menu.
8139 This feature is not enabled by default; since the Alt key is also the
8140 Meta key, it is too easy and painful to activate this feature by
8141 accident.
8142
8143 ** The command apply-macro-to-region-lines repeats the last defined
8144 keyboard macro once for each complete line within the current region.
8145 It does this line by line, by moving point to the beginning of that
8146 line and then executing the macro.
8147
8148 This command is not new, but was never documented before.
8149
8150 ** You can now use Mouse-1 to place the region around a string constant
8151 (something surrounded by doublequote characters or other delimiter
8152 characters of like syntax) by double-clicking on one of the delimiting
8153 characters.
8154
8155 ** Font Lock mode
8156
8157 *** Font Lock support modes
8158
8159 Font Lock can be configured to use Fast Lock mode and Lazy Lock mode (see
8160 below) in a flexible way. Rather than adding the appropriate function to the
8161 hook font-lock-mode-hook, you can use the new variable font-lock-support-mode
8162 to control which modes have Fast Lock mode or Lazy Lock mode turned on when
8163 Font Lock mode is enabled.
8164
8165 For example, to use Fast Lock mode when Font Lock mode is turned on, put:
8166
8167 (setq font-lock-support-mode 'fast-lock-mode)
8168
8169 in your ~/.emacs.
8170
8171 *** lazy-lock
8172
8173 The lazy-lock package speeds up Font Lock mode by making fontification occur
8174 only when necessary, such as when a previously unfontified part of the buffer
8175 becomes visible in a window. When you create a buffer with Font Lock mode and
8176 Lazy Lock mode turned on, the buffer is not fontified. When certain events
8177 occur (such as scrolling), Lazy Lock makes sure that the visible parts of the
8178 buffer are fontified. Lazy Lock also defers on-the-fly fontification until
8179 Emacs has been idle for a given amount of time.
8180
8181 To use this package, put in your ~/.emacs:
8182
8183 (setq font-lock-support-mode 'lazy-lock-mode)
8184
8185 To control the package behaviour, see the documentation for `lazy-lock-mode'.
8186
8187 ** Changes in BibTeX mode.
8188
8189 *** For all entries allow spaces and tabs between opening brace or
8190 paren and key.
8191
8192 *** Non-escaped double-quoted characters (as in `Sch"of') are now
8193 supported.
8194
8195 ** Gnus changes.
8196
8197 Gnus, the Emacs news reader, has undergone further rewriting. Many new
8198 commands and variables have been added. There should be no
8199 significant incompatibilities between this Gnus version and the
8200 previously released version, except in the message composition area.
8201
8202 Below is a list of the more user-visible changes. Coding changes
8203 between Gnus 5.1 and 5.2 are more extensive.
8204
8205 *** A new message composition mode is used. All old customization
8206 variables for mail-mode, rnews-reply-mode and gnus-msg are now
8207 obsolete.
8208
8209 *** Gnus is now able to generate "sparse" threads -- threads where
8210 missing articles are represented by empty nodes.
8211
8212 (setq gnus-build-sparse-threads 'some)
8213
8214 *** Outgoing articles are stored on a special archive server.
8215
8216 To disable this: (setq gnus-message-archive-group nil)
8217
8218 *** Partial thread regeneration now happens when articles are
8219 referred.
8220
8221 *** Gnus can make use of GroupLens predictions:
8222
8223 (setq gnus-use-grouplens t)
8224
8225 *** A trn-line tree buffer can be displayed.
8226
8227 (setq gnus-use-trees t)
8228
8229 *** An nn-like pick-and-read minor mode is available for the summary
8230 buffers.
8231
8232 (add-hook 'gnus-summary-mode-hook 'gnus-pick-mode)
8233
8234 *** In binary groups you can use a special binary minor mode:
8235
8236 `M-x gnus-binary-mode'
8237
8238 *** Groups can be grouped in a folding topic hierarchy.
8239
8240 (add-hook 'gnus-group-mode-hook 'gnus-topic-mode)
8241
8242 *** Gnus can re-send and bounce mail.
8243
8244 Use the `S D r' and `S D b'.
8245
8246 *** Groups can now have a score, and bubbling based on entry frequency
8247 is possible.
8248
8249 (add-hook 'gnus-summary-exit-hook 'gnus-summary-bubble-group)
8250
8251 *** Groups can be process-marked, and commands can be performed on
8252 groups of groups.
8253
8254 *** Caching is possible in virtual groups.
8255
8256 *** nndoc now understands all kinds of digests, mail boxes, rnews news
8257 batches, ClariNet briefs collections, and just about everything else.
8258
8259 *** Gnus has a new backend (nnsoup) to create/read SOUP packets.
8260
8261 *** The Gnus cache is much faster.
8262
8263 *** Groups can be sorted according to many criteria.
8264
8265 For instance: (setq gnus-group-sort-function 'gnus-group-sort-by-rank)
8266
8267 *** New group parameters have been introduced to set list-address and
8268 expiration times.
8269
8270 *** All formatting specs allow specifying faces to be used.
8271
8272 *** There are several more commands for setting/removing/acting on
8273 process marked articles on the `M P' submap.
8274
8275 *** The summary buffer can be limited to show parts of the available
8276 articles based on a wide range of criteria. These commands have been
8277 bound to keys on the `/' submap.
8278
8279 *** Articles can be made persistent -- as an alternative to saving
8280 articles with the `*' command.
8281
8282 *** All functions for hiding article elements are now toggles.
8283
8284 *** Article headers can be buttonized.
8285
8286 (add-hook 'gnus-article-display-hook 'gnus-article-add-buttons-to-head)
8287
8288 *** All mail backends support fetching articles by Message-ID.
8289
8290 *** Duplicate mail can now be treated properly. See the
8291 `nnmail-treat-duplicates' variable.
8292
8293 *** All summary mode commands are available directly from the article
8294 buffer.
8295
8296 *** Frames can be part of `gnus-buffer-configuration'.
8297
8298 *** Mail can be re-scanned by a daemonic process.
8299
8300 *** Gnus can make use of NoCeM files to filter spam.
8301
8302 (setq gnus-use-nocem t)
8303
8304 *** Groups can be made permanently visible.
8305
8306 (setq gnus-permanently-visible-groups "^nnml:")
8307
8308 *** Many new hooks have been introduced to make customizing easier.
8309
8310 *** Gnus respects the Mail-Copies-To header.
8311
8312 *** Threads can be gathered by looking at the References header.
8313
8314 (setq gnus-summary-thread-gathering-function
8315 'gnus-gather-threads-by-references)
8316
8317 *** Read articles can be stored in a special backlog buffer to avoid
8318 refetching.
8319
8320 (setq gnus-keep-backlog 50)
8321
8322 *** A clean copy of the current article is always stored in a separate
8323 buffer to allow easier treatment.
8324
8325 *** Gnus can suggest where to save articles. See `gnus-split-methods'.
8326
8327 *** Gnus doesn't have to do as much prompting when saving.
8328
8329 (setq gnus-prompt-before-saving t)
8330
8331 *** gnus-uu can view decoded files asynchronously while fetching
8332 articles.
8333
8334 (setq gnus-uu-grabbed-file-functions 'gnus-uu-grab-view)
8335
8336 *** Filling in the article buffer now works properly on cited text.
8337
8338 *** Hiding cited text adds buttons to toggle hiding, and how much
8339 cited text to hide is now customizable.
8340
8341 (setq gnus-cited-lines-visible 2)
8342
8343 *** Boring headers can be hidden.
8344
8345 (add-hook 'gnus-article-display-hook 'gnus-article-hide-boring-headers)
8346
8347 *** Default scoring values can now be set from the menu bar.
8348
8349 *** Further syntax checking of outgoing articles have been added.
8350
8351 The Gnus manual has been expanded. It explains all these new features
8352 in greater detail.
8353 \f
8354 * Lisp Changes in Emacs 19.32
8355
8356 ** The function set-visited-file-name now accepts an optional
8357 second argument NO-QUERY. If it is non-nil, then the user is not
8358 asked for confirmation in the case where the specified file already
8359 exists.
8360
8361 ** The variable print-length applies to printing vectors and bitvectors,
8362 as well as lists.
8363
8364 ** The new function keymap-parent returns the parent keymap
8365 of a given keymap.
8366
8367 ** The new function set-keymap-parent specifies a new parent for a
8368 given keymap. The arguments are KEYMAP and PARENT. PARENT must be a
8369 keymap or nil.
8370
8371 ** Sometimes menu keymaps use a command name, a symbol, which is really
8372 an automatically generated alias for some other command, the "real"
8373 name. In such a case, you should give that alias symbol a non-nil
8374 menu-alias property. That property tells the menu system to look for
8375 equivalent keys for the real name instead of equivalent keys for the
8376 alias.
8377 \f
8378 * Editing Changes in Emacs 19.31
8379
8380 ** Freedom of the press restricted in the United States.
8381
8382 Emacs has been censored in accord with the Communications Decency Act.
8383 This includes removing some features of the doctor program. That law
8384 was described by its supporters as a ban on pornography, but it bans
8385 far more than that. The Emacs distribution has never contained any
8386 pornography, but parts of it were nonetheless prohibited.
8387
8388 For information on US government censorship of the Internet, and what
8389 you can do to bring back freedom of the press, see the web site
8390 `http://www.vtw.org/'.
8391
8392 ** A note about C mode indentation customization.
8393
8394 The old (Emacs 19.29) ways of specifying a C indentation style
8395 do not normally work in the new implementation of C mode.
8396 It has its own methods of customizing indentation, which are
8397 much more powerful than the old C mode. See the Editing Programs
8398 chapter of the manual for details.
8399
8400 However, you can load the library cc-compat to make the old
8401 customization variables take effect.
8402
8403 ** Marking with the mouse.
8404
8405 When you mark a region with the mouse, the region now remains
8406 highlighted until the next input event, regardless of whether you are
8407 using M-x transient-mark-mode.
8408
8409 ** Improved Windows NT/95 support.
8410
8411 *** Emacs now supports scroll bars on Windows NT and Windows 95.
8412
8413 *** Emacs now supports subprocesses on Windows 95. (Subprocesses used
8414 to work on NT only and not on 95.)
8415
8416 *** There are difficulties with subprocesses, though, due to problems
8417 in Windows, beyond the control of Emacs. They work fine as long as
8418 you run Windows applications. The problems arise when you run a DOS
8419 application in a subprocesses. Since current shells run as DOS
8420 applications, these problems are significant.
8421
8422 If you run a DOS application in a subprocess, then the application is
8423 likely to busy-wait, which means that your machine will be 100% busy.
8424 However, if you don't mind the temporary heavy load, the subprocess
8425 will work OK as long as you tell it to terminate before you start any
8426 other DOS application as a subprocess.
8427
8428 Emacs is unable to terminate or interrupt a DOS subprocess.
8429 You have to do this by providing input directly to the subprocess.
8430
8431 If you run two DOS applications at the same time in two separate
8432 subprocesses, even if one of them is asynchronous, you will probably
8433 have to reboot your machine--until then, it will remain 100% busy.
8434 Windows simply does not cope when one Windows process tries to run two
8435 separate DOS subprocesses. Typing CTL-ALT-DEL and then choosing
8436 Shutdown seems to work although it may take a few minutes.
8437
8438 ** M-x resize-minibuffer-mode.
8439
8440 This command, not previously mentioned in NEWS, toggles a mode in
8441 which the minibuffer window expands to show as many lines as the
8442 minibuffer contains.
8443
8444 ** `title' frame parameter and resource.
8445
8446 The `title' X resource now specifies just the frame title, nothing else.
8447 It does not affect the name used for looking up other X resources.
8448 It works by setting the new `title' frame parameter, which likewise
8449 affects just the displayed title of the frame.
8450
8451 The `name' parameter continues to do what it used to do:
8452 it specifies the frame name for looking up X resources,
8453 and also serves as the default for the displayed title
8454 when the `title' parameter is unspecified or nil.
8455
8456 ** Emacs now uses the X toolkit by default, if you have a new
8457 enough version of X installed (X11R5 or newer).
8458
8459 ** When you compile Emacs with the Motif widget set, Motif handles the
8460 F10 key by activating the menu bar. To avoid confusion, the usual
8461 Emacs binding of F10 is replaced with a no-op when using Motif.
8462
8463 If you want to be able to use F10 in Emacs, you can rebind the Motif
8464 menubar to some other key which you don't use. To do so, add
8465 something like this to your X resources file. This example rebinds
8466 the Motif menu bar activation key to S-F12:
8467
8468 Emacs*defaultVirtualBindings: osfMenuBar : Shift<Key>F12
8469
8470 ** In overwrite mode, DEL now inserts spaces in most cases
8471 to replace the characters it "deletes".
8472
8473 ** The Rmail summary now shows the number of lines in each message.
8474
8475 ** Rmail has a new command M-x unforward-rmail-message, which extracts
8476 a forwarded message from the message that forwarded it. To use it,
8477 select a message which contains a forwarded message and then type the command.
8478 It inserts the forwarded message as a separate Rmail message
8479 immediately after the selected one.
8480
8481 This command also undoes the textual modifications that are standardly
8482 made, as part of forwarding, by Rmail and other mail reader programs.
8483
8484 ** Turning off saving of .saves-... files in your home directory.
8485
8486 Each Emacs session writes a file named .saves-... in your home
8487 directory to record which files M-x recover-session should recover.
8488 If you exit Emacs normally with C-x C-c, it deletes that file. If
8489 Emacs or the operating system crashes, the file remains for M-x
8490 recover-session.
8491
8492 You can turn off the writing of these files by setting
8493 auto-save-list-file-name to nil. If you do this, M-x recover-session
8494 will not work.
8495
8496 Some previous Emacs versions failed to delete these files even on
8497 normal exit. This is fixed now. If you are thinking of turning off
8498 this feature because of past experiences with versions that had this
8499 bug, it would make sense to check whether you still want to do so
8500 now that the bug is fixed.
8501
8502 ** Changes to Version Control (VC)
8503
8504 There is a new variable, vc-follow-symlinks. It indicates what to do
8505 when you visit a link to a file that is under version control.
8506 Editing the file through the link bypasses the version control system,
8507 which is dangerous and probably not what you want.
8508
8509 If this variable is t, VC follows the link and visits the real file,
8510 telling you about it in the echo area. If it is `ask' (the default),
8511 VC asks for confirmation whether it should follow the link. If nil,
8512 the link is visited and a warning displayed.
8513
8514 ** iso-acc.el now lets you specify a choice of language.
8515 Languages include "latin-1" (the default) and "latin-2" (which
8516 is designed for entering ISO Latin-2 characters).
8517
8518 There are also choices for specific human languages such as French and
8519 Portuguese. These are subsets of Latin-1, which differ in that they
8520 enable only the accent characters needed for particular language.
8521 The other accent characters, not needed for the chosen language,
8522 remain normal.
8523
8524 ** Posting articles and sending mail now has M-TAB completion on various
8525 header fields (Newsgroups, To, CC, ...).
8526
8527 Completion in the Newsgroups header depends on the list of groups
8528 known to your news reader. Completion in the Followup-To header
8529 offers those groups which are in the Newsgroups header, since
8530 Followup-To usually just holds one of those.
8531
8532 Completion in fields that hold mail addresses works based on the list
8533 of local users plus your aliases. Additionally, if your site provides
8534 a mail directory or a specific host to use for any unrecognized user
8535 name, you can arrange to query that host for completion also. (See the
8536 documentation of variables `mail-directory-process' and
8537 `mail-directory-stream'.)
8538
8539 ** A greatly extended sgml-mode offers new features such as (to be configured)
8540 skeletons with completing read for tags and attributes, typing named
8541 characters including optionally all 8bit characters, making tags invisible
8542 with optional alternate display text, skipping and deleting tag(pair)s.
8543
8544 Note: since Emacs' syntax feature cannot limit the special meaning of ', " and
8545 - to inside <>, for some texts the result, especially of font locking, may be
8546 wrong (see `sgml-specials' if you get wrong results).
8547
8548 The derived html-mode configures this with tags and attributes more or
8549 less HTML3ish. It also offers optional quick keys like C-c 1 for
8550 headline or C-c u for unordered list (see `html-quick-keys'). Edit /
8551 Text Properties / Face or M-g combinations create tags as applicable.
8552 Outline minor mode is supported and level 1 font-locking tries to
8553 fontify tag contents (which only works when they fit on one line, due
8554 to a limitation in font-lock).
8555
8556 External viewing via browse-url can occur automatically upon saving.
8557
8558 ** M-x imenu-add-to-menubar now adds to the menu bar for the current
8559 buffer only. If you want to put an Imenu item in the menu bar for all
8560 buffers that use a particular major mode, use the mode hook, as in
8561 this example:
8562
8563 (add-hook 'emacs-lisp-mode-hook
8564 '(lambda () (imenu-add-to-menubar "Index")))
8565
8566 ** Changes in BibTeX mode.
8567
8568 *** Field names may now contain digits, hyphens, and underscores.
8569
8570 *** Font Lock mode is now supported.
8571
8572 *** bibtex-make-optional-field is no longer interactive.
8573
8574 *** If bibtex-maintain-sorted-entries is non-nil, inserting new
8575 entries is now done with a faster algorithm. However, inserting
8576 will fail in this case if the buffer contains invalid entries or
8577 isn't in sorted order, so you should finish each entry with C-c C-c
8578 (bibtex-close-entry) after you have inserted or modified it.
8579 The default value of bibtex-maintain-sorted-entries is nil.
8580
8581 *** Function `show-all' is no longer bound to a key, since C-u C-c C-q
8582 does the same job.
8583
8584 *** Entries with quotes inside quote-delimited fields (as `author =
8585 "Stefan Sch{\"o}f"') are now supported.
8586
8587 *** Case in field names doesn't matter anymore when searching for help
8588 text.
8589
8590 ** Font Lock mode
8591
8592 *** Global Font Lock mode
8593
8594 Font Lock mode can be turned on globally, in buffers that support it, by the
8595 new command global-font-lock-mode. You can use the new variable
8596 font-lock-global-modes to control which modes have Font Lock mode automagically
8597 turned on. By default, this variable is set so that Font Lock mode is turned
8598 on globally where the buffer mode supports it.
8599
8600 For example, to automagically turn on Font Lock mode where supported, put:
8601
8602 (global-font-lock-mode t)
8603
8604 in your ~/.emacs.
8605
8606 *** Local Refontification
8607
8608 In Font Lock mode, editing a line automatically refontifies that line only.
8609 However, if your change alters the syntactic context for following lines,
8610 those lines remain incorrectly fontified. To refontify them, use the new
8611 command M-g M-g (font-lock-fontify-block).
8612
8613 In certain major modes, M-g M-g refontifies the entire current function.
8614 (The variable font-lock-mark-block-function controls how to find the
8615 current function.) In other major modes, M-g M-g refontifies 16 lines
8616 above and below point.
8617
8618 With a prefix argument N, M-g M-g refontifies N lines above and below point.
8619
8620 ** Follow mode
8621
8622 Follow mode is a new minor mode combining windows showing the same
8623 buffer into one tall "virtual window". The windows are typically two
8624 side-by-side windows. Follow mode makes them scroll together as if
8625 they were a unit. To use it, go to a frame with just one window,
8626 split it into two side-by-side windows using C-x 3, and then type M-x
8627 follow-mode.
8628
8629 M-x follow-mode turns off Follow mode if it is already enabled.
8630
8631 To display two side-by-side windows and activate Follow mode, use the
8632 command M-x follow-delete-other-windows-and-split.
8633
8634 ** hide-show changes.
8635
8636 The hooks hs-hide-hooks and hs-show-hooks have been renamed
8637 to hs-hide-hook and hs-show-hook, to follow the convention for
8638 normal hooks.
8639
8640 ** Simula mode now has a menu containing the most important commands.
8641 The new command simula-indent-exp is bound to C-M-q.
8642
8643 ** etags can now handle programs written in Erlang. Files are
8644 recognised by the extensions .erl and .hrl. The tagged lines are
8645 those that begin a function, record, or macro.
8646
8647 ** MSDOS Changes
8648
8649 *** It is now possible to compile Emacs with the version 2 of DJGPP.
8650 Compilation with DJGPP version 1 also still works.
8651
8652 *** The documentation of DOS-specific aspects of Emacs was rewritten
8653 and expanded; see the ``MS-DOS'' node in the on-line docs.
8654
8655 *** Emacs now uses ~ for backup file names, not .bak.
8656
8657 *** You can simulate mouse-3 on two-button mice by simultaneously
8658 pressing both mouse buttons.
8659
8660 *** A number of packages and commands which previously failed or had
8661 restricted functionality on MS-DOS, now work. The most important ones
8662 are:
8663
8664 **** Printing (both with `M-x lpr-buffer' and with `ps-print' package)
8665 now works.
8666
8667 **** `Ediff' works (in a single-frame mode).
8668
8669 **** `M-x display-time' can be used on MS-DOS (due to the new
8670 implementation of Emacs timers, see below).
8671
8672 **** `Dired' supports Unix-style shell wildcards.
8673
8674 **** The `c-macro-expand' command now works as on other platforms.
8675
8676 **** `M-x recover-session' works.
8677
8678 **** `M-x list-colors-display' displays all the available colors.
8679
8680 **** The `TPU-EDT' package works.
8681 \f
8682 * Lisp changes in Emacs 19.31.
8683
8684 ** The function using-unix-filesystems on Windows NT and Windows 95
8685 tells Emacs to read and write files assuming that they reside on a
8686 remote Unix filesystem. No CR/LF translation is done on any files in
8687 this case. Invoking using-unix-filesystems with t activates this
8688 behavior, and invoking it with any other value deactivates it.
8689
8690 ** Change in system-type and system-configuration values.
8691
8692 The value of system-type on a Linux-based GNU system is now `lignux',
8693 not `linux'. This means that some programs which use `system-type'
8694 need to be changed. The value of `system-configuration' will also
8695 be different.
8696
8697 It is generally recommended to use `system-configuration' rather
8698 than `system-type'.
8699
8700 See the file LINUX-GNU in this directory for more about this.
8701
8702 ** The functions shell-command and dired-call-process
8703 now run file name handlers for default-directory, if it has them.
8704
8705 ** Undoing the deletion of text now restores the positions of markers
8706 that pointed into or next to the deleted text.
8707
8708 ** Timers created with run-at-time now work internally to Emacs, and
8709 no longer use a separate process. Therefore, they now work more
8710 reliably and can be used for shorter time delays.
8711
8712 The new function run-with-timer is a convenient way to set up a timer
8713 to run a specified amount of time after the present. A call looks
8714 like this:
8715
8716 (run-with-timer SECS REPEAT FUNCTION ARGS...)
8717
8718 SECS says how many seconds should elapse before the timer happens.
8719 It may be an integer or a floating point number. When the timer
8720 becomes ripe, the action is to call FUNCTION with arguments ARGS.
8721
8722 REPEAT gives the interval for repeating the timer (measured in
8723 seconds). It may be an integer or a floating point number. nil or 0
8724 means don't repeat at all--call FUNCTION just once.
8725
8726 *** with-timeout provides an easy way to do something but give
8727 up if too much time passes.
8728
8729 (with-timeout (SECONDS TIMEOUT-FORMS...) BODY...)
8730
8731 This executes BODY, but gives up after SECONDS seconds.
8732 If it gives up, it runs the TIMEOUT-FORMS and returns the value
8733 of the last one of them. Normally it returns the value of the last
8734 form in BODY.
8735
8736 *** You can now arrange to call a function whenever Emacs is idle for
8737 a certain length of time. To do this, call run-with-idle-timer. A
8738 call looks like this:
8739
8740 (run-with-idle-timer SECS REPEAT FUNCTION ARGS...)
8741
8742 SECS says how many seconds of idleness should elapse before the timer
8743 runs. It may be an integer or a floating point number. When the
8744 timer becomes ripe, the action is to call FUNCTION with arguments
8745 ARGS.
8746
8747 Emacs becomes idle whenever it finishes executing a keyboard or mouse
8748 command. It remains idle until it receives another keyboard or mouse
8749 command.
8750
8751 REPEAT, if non-nil, means this timer should be activated again each
8752 time Emacs becomes idle and remains idle for SECS seconds The timer
8753 does not repeat if Emacs *remains* idle; it runs at most once after
8754 each time Emacs becomes idle.
8755
8756 If REPEAT is nil, the timer runs just once, the first time Emacs is
8757 idle for SECS seconds.
8758
8759 *** post-command-idle-hook is now obsolete; you shouldn't use it at
8760 all, because it interferes with the idle timer mechanism. If your
8761 programs use post-command-idle-hook, convert them to use idle timers
8762 instead.
8763
8764 *** y-or-n-p-with-timeout lets you ask a question but give up if
8765 there is no answer within a certain time.
8766
8767 (y-or-n-p-with-timeout PROMPT SECONDS DEFAULT-VALUE)
8768
8769 asks the question PROMPT (just like y-or-n-p). If the user answers
8770 within SECONDS seconds, it returns the answer that the user gave.
8771 Otherwise it gives up after SECONDS seconds, and returns DEFAULT-VALUE.
8772
8773 ** Minor change to `encode-time': you can now pass more than seven
8774 arguments. If you do that, the first six arguments have the usual
8775 meaning, the last argument is interpreted as the time zone, and the
8776 arguments in between are ignored.
8777
8778 This means that it works to use the list returned by `decode-time' as
8779 the list of arguments for `encode-time'.
8780
8781 ** The default value of load-path now includes the directory
8782 /usr/local/share/emacs/VERSION/site-lisp In addition to
8783 /usr/local/share/emacs/site-lisp. You can use this new directory for
8784 site-specific Lisp packages that belong with a particular Emacs
8785 version.
8786
8787 It is not unusual for a Lisp package that works well in one Emacs
8788 version to cause trouble in another. Sometimes packages need updating
8789 for incompatible changes; sometimes they look at internal data that
8790 has changed; sometimes the package has been installed in Emacs itself
8791 and the installed version should be used. Whatever the reason for the
8792 problem, this new feature makes it easier to solve.
8793
8794 ** When your program contains a fixed file name (like .completions or
8795 .abbrev.defs), the file name usually needs to be different on operating
8796 systems with limited file name syntax.
8797
8798 Now you can avoid ad-hoc conditionals by using the function
8799 convert-standard-filename to convert the file name to a proper form
8800 for each operating system. Here is an example of use, from the file
8801 completions.el:
8802
8803 (defvar save-completions-file-name
8804 (convert-standard-filename "~/.completions")
8805 "*The filename to save completions to.")
8806
8807 This sets the variable save-completions-file-name to a value that
8808 depends on the operating system, because the definition of
8809 convert-standard-filename depends on the operating system. On
8810 Unix-like systems, it returns the specified file name unchanged. On
8811 MS-DOS, it adapts the name to fit the limitations of that system.
8812
8813 ** The interactive spec N now returns the numeric prefix argument
8814 rather than the raw prefix argument. (It still reads a number using the
8815 minibuffer if there is no prefix argument at all.)
8816
8817 ** When a process is deleted, this no longer disconnects the process
8818 marker from its buffer position.
8819
8820 ** The variable garbage-collection-messages now controls whether
8821 Emacs displays a message at the beginning and end of garbage collection.
8822 The default is nil, meaning there are no messages.
8823
8824 ** The variable debug-ignored-errors specifies certain kinds of errors
8825 that should not enter the debugger. Its value is a list of error
8826 condition symbols and/or regular expressions. If the error has any
8827 of the condition symbols listed, or if any of the regular expressions
8828 matches the error message, then that error does not enter the debugger,
8829 regardless of the value of debug-on-error.
8830
8831 This variable is initialized to match certain common but uninteresting
8832 errors that happen often during editing.
8833
8834 ** The new function error-message-string converts an error datum
8835 into its error message. The error datum is what condition-case
8836 puts into the variable, to describe the error that happened.
8837
8838 ** Anything that changes which buffer appears in a given window
8839 now runs the window-scroll-functions for that window.
8840
8841 ** The new function get-buffer-window-list returns a list of windows displaying
8842 a buffer. The function is called with the buffer (a buffer object or a buffer
8843 name) and two optional arguments specifying the minibuffer windows and frames
8844 to search. Therefore this function takes optional args like next-window etc.,
8845 and not get-buffer-window.
8846
8847 ** buffer-substring now runs the hook buffer-access-fontify-functions,
8848 calling each function with two arguments--the range of the buffer
8849 being accessed. buffer-substring-no-properties does not call them.
8850
8851 If you use this feature, you should set the variable
8852 buffer-access-fontified-property to a non-nil symbol, which is a
8853 property name. Then, if all the characters in the buffer range have a
8854 non-nil value for that property, the buffer-access-fontify-functions
8855 are not called. When called, these functions should put a non-nil
8856 property on the text that they fontify, so that they won't get called
8857 over and over for the same text.
8858
8859 ** Changes in lisp-mnt.el
8860
8861 *** The lisp-mnt package can now recognize file headers that are written
8862 in the formats used by the `what' command and the RCS `ident' command:
8863
8864 ;; @(#) HEADER: text
8865 ;; $HEADER: text $
8866
8867 in addition to the normal
8868
8869 ;; HEADER: text
8870
8871 *** The commands lm-verify and lm-synopsis are now interactive. lm-verify
8872 checks that the library file has proper sections and headers, and
8873 lm-synopsis extracts first line "synopsis'"information.
8874
8875
8876 \f
8877 * For older news, see the file ONEWS
8878
8879 ----------------------------------------------------------------------
8880 Copyright information:
8881
8882 Copyright (C) 1999, 2000 Free Software Foundation, Inc.
8883
8884 Permission is granted to anyone to make or distribute verbatim copies
8885 of this document as received, in any medium, provided that the
8886 copyright notice and this permission notice are preserved,
8887 thus giving the recipient permission to redistribute in turn.
8888
8889 Permission is granted to distribute modified versions
8890 of this document, or of portions of it,
8891 under the above conditions, provided also that they
8892 carry prominent notices stating who last changed them.
8893 \f
8894 Local variables:
8895 mode: outline
8896 paragraph-separate: "[ \f]*$"
8897 end: