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1 GNU Emacs NEWS -- history of user-visible changes. 2000-09-27
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 and also on Irix 6.5. This increases the
30 maximum buffer size. See etc/MACHINES for instructions.
31
32 \f
33 * Changes in Emacs 21.1
34
35 ** `browse-url-gnome-moz' is a new option for
36 `browse-url-browser-function', invoking Mozilla in GNOME.
37
38 +++
39 ** The new global minor mode `auto-image-file-mode' allows image files
40 to be visited as images.
41
42 ** The functions `keep-lines', `flush-lines' and `how-many' now
43 operate on the active region in Transient Mark mode.
44
45 ** The header line in an Info buffer is now displayed as an emacs header-line
46 (which is like a mode-line, but at the top of the window), so that it
47 remains visible even when the buffer has been scrolled. This behavior
48 may be disabled by customizing the option `Info-use-header-line'.
49
50 ** `gnus-user-agent' is a new possibility for `mail-user-agent'. It
51 is like `message-user-agent', but with all the Gnus paraphernalia.
52
53 +++
54 ** The recommended way of using Iswitchb is via the new global minor
55 mode `iswitchb-mode'.
56
57 ** Gnus changes.
58
59 The Gnus NEWS entries are short, but they reflect sweeping changes in
60 four areas: Article display treatment, MIME treatment,
61 internationalization and mail-fetching.
62
63 *** The mail-fetching functions have changed. See the manual for the
64 many details. In particular, all procmail fetching variables are gone.
65
66 If you used procmail like in
67
68 (setq nnmail-use-procmail t)
69 (setq nnmail-spool-file 'procmail)
70 (setq nnmail-procmail-directory "~/mail/incoming/")
71 (setq nnmail-procmail-suffix "\\.in")
72
73 this now has changed to
74
75 (setq mail-sources
76 '((directory :path "~/mail/incoming/"
77 :suffix ".in")))
78
79 More information is available in the info doc at Select Methods ->
80 Getting Mail -> Mail Sources
81
82 *** Gnus is now a MIME-capable reader. This affects many parts of
83 Gnus, and adds a slew of new commands. See the manual for details.
84
85 *** Gnus has also been multilingualized. This also affects too many
86 parts of Gnus to summarize here, and adds many new variables.
87 Separate MIME packages like SEMI will not work. There are built-in
88 facilities equivalent to those of gnus-mule.el, which is now just a
89 compatibility layer.
90
91 *** gnus-auto-select-first can now be a function to be
92 called to position point.
93
94 *** The user can now decide which extra headers should be included in
95 summary buffers and NOV files.
96
97 *** `gnus-article-display-hook' has been removed. Instead, a number
98 of variables starting with `gnus-treat-' have been added.
99
100 *** The Gnus posting styles have been redone again and now work in a
101 subtly different manner.
102
103 *** New web-based backends have been added: nnslashdot, nnwarchive
104 and nnultimate. nnweb has been revamped, again, to keep up with
105 ever-changing layouts.
106
107 *** Gnus can now read IMAP mail via nnimap.
108
109 *** There is image support.
110
111 ** When your terminal can't display characters from some of the ISO
112 8859 character sets but can display Latin-1, you can display
113 more-or-less mnemonic sequences of ASCII/Latin-1 characters instead of
114 empty boxes (under a window system) or question marks (not under a
115 window system). Customize the option `latin1-display' to turn this
116 on.
117
118 ** The new user-option `find-file-suppress-same-file-warnings' can be
119 set to suppress warnings ``X and Y are the same file'' when visiting a
120 file that is already visited under a different name.
121
122 ** The new user-option `electric-help-shrink-window' can be set to
123 nil to prevent adjusting the help window size to the buffer size.
124
125 ** Emacs now checks for recursive loads of Lisp files. If the
126 recursion depth exceeds `recursive-load-depth-limit', an error is
127 signaled.
128
129 ** The Strokes package has been updated. If your Emacs has XPM
130 support, you can use it for pictographic editing. In Strokes mode,
131 use C-mouse-2 to compose a complex stoke and insert it into the
132 buffer. You can encode or decode a strokes buffer with new commands
133 M-x strokes-encode-buffer and M-x strokes-decode-buffer. There is a
134 new command M-x strokes-list-strokes.
135
136 +++
137 ** New command M-x describe-character-set reads a character set name
138 and displays information about that.
139
140 ** When an error is signaled during the loading of the user's init
141 file, Emacs now pops up the *Messages* buffer.
142
143 ** Polish and German translations of Emacs' reference card have been
144 added. They are named `pl-refcard.tex' and `de-refcard.tex'.
145 Postscript files are included.
146
147 ** A reference card for Dired has been added. Its name is
148 `dired-ref.tex'.
149
150 ** The new variable `auto-mode-interpreter-regexp' contains a regular
151 expression matching interpreters, for file mode determination.
152
153 This regular expression is matched against the first line of a file to
154 determine the file's mode in `set-auto-mode' when Emacs can't deduce a
155 mode from the file's name. If it matches, the file is assumed to be
156 interpreted by the interpreter matched by the second group of the
157 regular expression. The mode is then determined as the mode
158 associated with that interpreter in `interpreter-mode-alist'.
159
160 ** C-down-mouse-3 is bound differently. Now if the menu bar is not
161 displayed it pops up a menu containing the items which would be on the
162 menu bar. If the menu bar is displayed, it pops up the major mode
163 menu or the Edit menu if there is no major mode menu.
164
165 ** Variable `load-path' is no longer customizable because it contains
166 a version-dependent component.
167
168 ** The <delete> function key is now bound to `delete-char' by default.
169 Note that this takes effect only on window systems. On TTYs, Emacs
170 will receive ASCII 127 when the DEL key is pressed. This
171 character is still bound as before.
172
173 ** Item Save Options on the Options menu allows saving options set
174 using that menu.
175
176 ** New function executable-make-buffer-file-executable-if-script-p is
177 suitable as an after-save-hook as an alternative to `executable-chmod'.
178
179 +++
180 ** The most preferred coding-system is now used to save a buffer if
181 buffer-file-coding-system is `undecided' and it is safe for the buffer
182 contents. (The most preferred is set by set-language-environment or
183 by M-x prefer-coding-system.) Thus if you visit an ASCII file and
184 insert a non-ASCII character from your current language environment,
185 the file will be saved silently with the appropriate coding.
186 Previously you would be prompted for a safe coding system.
187
188 +++
189 ** New variable `inhibit-iso-escape-detection' determines if Emacs'
190 coding system detection algorithm should pay attention to ISO2022's
191 escape sequences. If this variable is non-nil, the algorithm ignores
192 such escape sequences. The default value is nil, and it is
193 recommended not to change it except for the special case that you
194 always want to read any escape code verbatim. If you just want to
195 read a specific file without decoding escape codes, use C-x RET c
196 (`universal-coding-system-argument'). For instance, C-x RET c latin-1
197 RET C-x C-f filename RET.
198
199 ** Variable `default-korean-keyboard' is initialized properly from the
200 environment variable `HANGUL_KEYBOARD_TYPE'.
201
202 +++
203 ** C-u C-x = provides detailed information about the character at
204 point in a pop-up window.
205
206 +++
207 ** New command M-x list-charset-chars reads a character set name and
208 displays all characters in that character set.
209
210 ** M-x set-terminal-coding-system (C-x RET t) now allows CCL-based
211 coding systems such as cpXXX and cyrillic-koi8.
212
213 +++
214 ** M-; now calls comment-dwim which tries to do something clever based
215 on the context. M-x kill-comment is now an alias to comment-kill,
216 defined on newcomment.el.
217
218 +++
219 ** The function `getenv' is now callable interactively.
220
221 ** The many obsolete language `setup-...-environment' commands have
222 been removed -- use `set-language-environment'.
223
224 +++
225 ** New user options `display-time-mail-face' and
226 `display-time-use-mail-icon' control the appearance of mode-line mail
227 indicator used by the display-time package. On a suitable display the
228 indicator can be an icon and is mouse-sensitive.
229
230 +++
231 ** Emacs' auto-save list files are now by default stored in a
232 sub-directory `.emacs.d/auto-save-list/' of the user's home directory.
233 (On MS-DOS, this subdirectory's name is `_emacs.d/auto-save.list/'.)
234 You can customize `auto-save-list-prefix' to change this location.
235
236 +++
237 ** On window-systems, additional space can be put between text lines
238 on the display using several methods
239
240 +++
241 - By setting frame parameter `line-spacing' to PIXELS. PIXELS must be
242 a positive integer, and specifies that PIXELS number of pixels should
243 be put below text lines on the affected frame or frames.
244
245 +++
246 - By setting X resource `lineSpacing', class `LineSpacing'. This is
247 equivalent ot specifying the frame parameter.
248
249 - By specifying `--line-spacing=N' or `-lsp N' on the command line.
250
251 - By setting buffer-local variable `line-spacing'. The meaning is
252 the same, but applies to the a particular buffer only.
253
254 +++
255 ** The new command `clone-indirect-buffer' can be used to create
256 an indirect buffer that is a twin copy of the current buffer. The
257 command `clone-indirect-buffer-other-window', bound to C-x 4 c,
258 does the same but displays the indirect buffer in another window.
259
260 +++
261 ** New user options `backup-directory-alist' and
262 `make-backup-file-name-function' control the placement of backups,
263 typically in a single directory or in an invisible sub-directory.
264
265 ** New commands iso-iso2sgml and iso-sgml2iso convert between Latin-1
266 characters and the corresponding SGML (HTML) entities.
267
268 +++
269 ** Emacs now refuses to load compiled Lisp files which weren't
270 compiled with Emacs. Set `load-dangerous-libraries' to t to change
271 this behavior.
272
273 The reason for this change is an incompatible change in XEmacs' byte
274 compiler. Files compiled with XEmacs can contain byte codes that let
275 Emacs dump core.
276
277 +++
278 ** New X resources recognized
279
280 *** The X resource `synchronous', class `Synchronous', specifies
281 whether Emacs should run in synchronous mode. Synchronous mode
282 is useful for debugging X problems.
283
284 Example:
285
286 emacs.synchronous: true
287
288 *** The X resource `visualClass, class `VisualClass', specifies the
289 visual Emacs should use. The resource's value should be a string of
290 the form `CLASS-DEPTH', where CLASS is the name of the visual class,
291 and DEPTH is the requested color depth as a decimal number. Valid
292 visual class names are
293
294 TrueColor
295 PseudoColor
296 DirectColor
297 StaticColor
298 GrayScale
299 StaticGray
300
301 Visual class names specified as X resource are case-insensitive, i.e.
302 `pseudocolor', `Pseudocolor' and `PseudoColor' all have the same
303 meaning.
304
305 The program `xdpyinfo' can be used to list the visual classes
306 supported on your display, and which depths they have. If
307 `visualClass' is not specified, Emacs uses the display's default
308 visual.
309
310 Example:
311
312 emacs.visualClass: TrueColor-8
313
314 *** The X resource `privateColormap', class `PrivateColormap',
315 specifies that Emacs should use a private colormap if it is using the
316 default visual, and that visual is of class PseudoColor. Recognized
317 resource values are `true' or `on'.
318
319 Example:
320
321 emacs.privateColormap: true
322
323 ** The menu bar configuration has changed. The new configuration is
324 more CUA-compliant. The most significant change is that Options is
325 now a separate menu-bar item, with Mule and Customize as its submenus.
326
327 ** User-option `show-cursor-in-non-selected-windows' controls how to
328 display the cursor in non-selected windows. If nil, no cursor is
329 shown, if non-nil a hollow box cursor is shown. This option can
330 be customized.
331
332 +++
333 ** The variable `echo-keystrokes' may now have a floating point value.
334
335 +++
336 ** C-x 5 1 runs the new command delete-other-frames which deletes
337 all frames except the selected one.
338
339 ** If your init file is compiled (.emacs.elc), `user-init-file' is set
340 to the source name (.emacs.el), if that exists, after loading it.
341
342 ** The help string specified for a menu-item whose definition contains
343 the property `:help HELP' is now displayed under X, on MS-Windows, and
344 MS-DOS, either in the echo area or with tooltips. Many standard menus
345 displayed by Emacs now have help strings.
346
347 +++
348 ** Highlighting of mouse-sensitive regions is now supported in the
349 MS-DOS version of Emacs.
350
351 ** New user option `read-mail-command' specifies a command to use to
352 read mail from the menu etc.
353
354 +++
355 ** Hexl contains a new command `hexl-insert-hex-string' which inserts
356 a string of hexadecimal numbers read from the mini-buffer.
357
358 ** Changes in Texinfo mode.
359
360 ** A couple of new key bindings have been added for inserting Texinfo
361 macros
362
363 Key binding Macro
364 -------------------------
365 C-c C-c C-s @strong
366 C-c C-c C-e @emph
367 C-c C-c u @url
368 C-c C-c q @quotation
369 C-c C-c m @email
370
371 ** Changes in Outline mode.
372
373 There is now support for Imenu to index headings. A new command
374 `outline-headers-as-kill' copies the visible headings in the region to
375 the kill ring, e.g. to produce a table of contents.
376
377 ** Changes to Emacs Server
378
379 +++
380 *** The new option `server-kill-new-buffers' specifies what to do
381 with buffers when done with them. If non-nil, the default, buffers
382 are killed, unless they were already present before visiting them with
383 Emacs Server. If nil, `server-temp-file-regexp' specifies which
384 buffers to kill, as before.
385
386 Please note that only buffers are killed that still have a client,
387 i.e. buffers visited with `emacsclient --no-wait' are never killed in
388 this way.
389
390 ** Changes to Show Paren mode.
391
392 *** Overlays used by Show Paren mode now use a priority property.
393 The new user option show-paren-priority specifies the priority to
394 use. Default is 1000.
395
396 +++
397 ** New command M-x check-parens can be used to find unbalanced paren
398 groups and strings in buffers in Lisp mode (or other modes).
399
400 +++
401 ** You can now easily create new *Info* buffers using either
402 M-x clone-buffer, C-u m <entry> RET or C-u g <entry> RET.
403 M-x clone-buffer can also be used on *Help* and several other special
404 buffers.
405
406 +++
407 ** Emacs can now support 'wheeled' mice (such as the MS IntelliMouse)
408 under XFree86. To enable this, simply put (mwheel-install) in your
409 .emacs file.
410
411 The variables `mwheel-follow-mouse' and `mwheel-scroll-amount'
412 determine where and by how much buffers are scrolled.
413
414 ** Listing buffers with M-x list-buffers (C-x C-b) now shows
415 abbreviated file names. Abbreviations can be customized by changing
416 `directory-abbrev-alist'.
417
418 ** Faces and frame parameters.
419
420 There are four new faces `scroll-bar', `border', `cursor' and `mouse'.
421 Setting the frame parameters `scroll-bar-foreground' and
422 `scroll-bar-background' sets foreground and background color of face
423 `scroll-bar' and vice versa. Setting frame parameter `border-color'
424 sets the background color of face `border' and vice versa. Likewise
425 for frame parameters `cursor-color' and face `cursor', and frame
426 parameter `mouse-color' and face `mouse'.
427
428 Changing frame parameter `font' sets font-related attributes of the
429 `default' face and vice versa. Setting frame parameters
430 `foreground-color' or `background-color' sets the colors of the
431 `default' face and vice versa.
432
433 +++
434 ** New face `menu'.
435
436 The face `menu' can be used to change colors and font of Emacs' menus.
437 Setting the font of LessTif/Motif menus is currently not supported;
438 attempts to set the font are ignored in this case.
439
440 +++
441 ** New frame parameter `screen-gamma' for gamma correction.
442
443 The new frame parameter `screen-gamma' specifies gamma-correction for
444 colors. Its value may be nil, the default, in which case no gamma
445 correction occurs, or a number > 0, usually a float, that specifies
446 the screen gamma of a frame's display.
447
448 PC monitors usually have a screen gamma of 2.2. smaller values result
449 in darker colors. You might want to try a screen gamma of 1.5 for LCD
450 color displays. The viewing gamma Emacs uses is 0.4545. (1/2.2).
451
452 The X resource name of this parameter is `screenGamma', class
453 `ScreenGamma'.
454
455 ** Emacs has a new redisplay engine.
456
457 The new redisplay handles characters of variable width and height.
458 Italic text can be used without redisplay problems. Fonts containing
459 oversized characters, i.e. characters larger than the logical height
460 of a font can be used. Images of various formats can be displayed in
461 the text.
462
463 ** Emacs has a new face implementation.
464
465 The new faces no longer fundamentally use X font names to specify the
466 font. Instead, each face has several independent attributes--family,
467 height, width, weight and slant--that it may or may not specify.
468 These attributes can be merged from various faces, and then together
469 specify a font.
470
471 Faces are supported on terminals that can display color or fonts.
472 These terminal capabilities are auto-detected. Details can be found
473 under Lisp changes, below.
474
475 ** New default font is Courier 12pt.
476
477 +++
478 ** When using a windowing terminal, each Emacs window now has a cursor
479 of its own. When the window is selected, the cursor is solid;
480 otherwise, it is hollow.
481
482 ** Bitmap areas to the left and right of windows are used to display
483 truncation marks, continuation marks, overlay arrows and alike. The
484 foreground, background, and stipple of these areas can be changed by
485 customizing face `fringe'.
486
487 ** The mode line under X is now drawn with shadows by default. You
488 can change its appearance by modifying the face `modeline'.
489
490 ** LessTif support.
491
492 Emacs now runs with the LessTif toolkit (see <http://www.lesstif.org>).
493 You will need a version 0.88.1 or later.
494
495 ** Toolkit scroll bars.
496
497 Emacs now uses toolkit scrollbars if available. When configured for
498 LessTif/Motif, it will use that toolkit's scrollbar. Otherwise, when
499 configured for Lucid and Athena widgets, it will use the Xaw3d scroll
500 bar if Xaw3d is available. You can turn off the use of toolkit scroll
501 bars by specifying `--with-toolkit-scroll-bars=no' when configuring
502 Emacs.
503
504 When you encounter problems with the Xaw3d scroll bar, watch out how
505 Xaw3d is compiled on your system. If the Makefile generated from
506 Xaw3d's Imakefile contains a `-DNARROWPROTO' compiler option, and your
507 Emacs system configuration file `s/your-system.h' does not contain a
508 define for NARROWPROTO, you might consider adding it. Take
509 `s/freebsd.h' as an example.
510
511 Alternatively, if you don't have access to the Xaw3d source code, take
512 a look at your system's imake configuration file, for example in the
513 directory `/usr/X11R6/lib/X11/config' (paths are different on
514 different systems). You will find files `*.cf' there. If your
515 system's cf-file contains a line like `#define NeedWidePrototypes NO',
516 add a `#define NARROWPROTO' to your Emacs system configuration file.
517
518 The reason for this is that one Xaw3d function uses `double' or
519 `float' function parameters depending on the setting of NARROWPROTO.
520 This is not a problem when Imakefiles are used because each system's
521 image configuration file contains the necessary information. Since
522 Emacs doesn't use imake, this has do be done manually.
523
524 ** Toggle buttons and radio buttons in menus.
525
526 When compiled with LessTif (or Motif) support, Emacs uses toolkit
527 widgets for radio and toggle buttons in menus. When configured for
528 Lucid, Emacs draws radio buttons and toggle buttons similar to Motif.
529
530 +++
531 ** Highlighting of trailing whitespace.
532
533 When `show-trailing-whitespace' is non-nil, Emacs displays trailing
534 whitespace in the face `trailing-whitespace'. Trailing whitespace is
535 defined as spaces or tabs at the end of a line. To avoid busy
536 highlighting when entering new text, trailing whitespace is not
537 displayed if point is at the end of the line containing the
538 whitespace.
539
540 +++
541 ** Busy-cursor.
542
543 Emacs can optionally display a busy-cursor under X. You can turn the
544 display on or off by customizing group `cursor'.
545
546 +++
547 ** Blinking cursor
548
549 M-x blink-cursor-mode toggles a blinking cursor under X and on
550 terminals having terminal capabilities `vi', `vs', and `ve'. Blinking
551 and related parameters like frequency and delay can be customized in
552 the group `cursor'.
553
554 ** New font-lock support mode `jit-lock-mode'.
555
556 This support mode is roughly equivalent to `lazy-lock' but is
557 generally faster. It supports stealth and deferred fontification.
558 See the documentation of the function `jit-lock-mode' for more
559 details.
560
561 Font-lock uses jit-lock-mode as default support mode, so you don't
562 have to do anything to activate it.
563
564 ** Tabs and variable-width text.
565
566 Tabs are now displayed with stretch properties; the width of a tab is
567 defined as a multiple of the normal character width of a frame, and is
568 independent of the fonts used in the text where the tab appears.
569 Thus, tabs can be used to line up text in different fonts.
570
571 ** Enhancements of the Lucid menu bar
572
573 +++
574 *** The Lucid menu bar now supports the resource "margin".
575
576 emacs.pane.menubar.margin: 5
577
578 The default margin is 4 which makes the menu bar appear like the
579 LessTif/Motif one.
580
581 *** Arrows that indicate sub-menus are now drawn with shadows, as in
582 LessTif and Motif.
583
584 +++
585 ** Hscrolling in C code.
586
587 Horizontal scrolling now happens automatically if
588 `automatic-hscrolling' is set (the default). This setting can be
589 customized.
590
591 ** Tool bar support.
592
593 Emacs supports a tool bar at the top of a frame under X. For details
594 how to define a tool bar, see the page describing Lisp-level changes.
595 Tool-bar global minor mode controls whether or not it is displayed.
596 To make the tool bar more useful, we need contributions of extra icons
597 for specific modes (with copyright assignments).
598
599 +++
600 ** Mouse-sensitive mode line.
601
602 Different parts of the mode line under X have been made
603 mouse-sensitive. Moving the mouse to a mouse-sensitive part in the mode
604 line changes the appearance of the mouse pointer to an arrow, and help
605 about available mouse actions is displayed either in the echo area, or
606 in the tooltip window if you have enabled one.
607
608 Currently, the following actions have been defined:
609
610 - Mouse-1 on the buffer name in the mode line switches between two
611 buffers.
612
613 - Mouse-2 on the buffer-name switches to the next buffer, and
614 M-mouse-2 switches to the previous buffer in the buffer list.
615
616 - Mouse-3 on the buffer-name displays a buffer menu.
617
618 - Mouse-2 on the read-only or modified status in the mode line (`%' or
619 `*') toggles the status.
620
621 - Mouse-3 on the mode name display a minor-mode menu.
622
623 ** LessTif/Motif file selection dialog.
624
625 When Emacs is configured to use LessTif or Motif, reading a file name
626 from a menu will pop up a file selection dialog if `use-dialog-box' is
627 non-nil.
628
629 ** Emacs can display faces on TTY frames.
630
631 Emacs automatically detects terminals that are able to display colors.
632 Faces with a weight greater than normal are displayed extra-bright, if
633 the terminal supports it. Faces with a weight less than normal and
634 italic faces are displayed dimmed, if the terminal supports it.
635 Underlined faces are displayed underlined if possible. Other face
636 attributes such as `overline', `strike-through', and `box' are ignored
637 on terminals.
638
639 ** Sound support
640
641 Emacs supports playing sound files on GNU/Linux and FreeBSD (Voxware
642 driver and native BSD driver, a.k.a. Luigi's driver). Currently
643 supported file formats are RIFF-WAVE (*.wav) and Sun Audio (*.au).
644
645 +++
646 ** A new variable, backup-by-copying-when-privileged-mismatch, gives
647 the highest file uid for which backup-by-copying-when-mismatch will be
648 forced on. The assumption is that uids less than or equal to this
649 value are special uids (root, bin, daemon, etc.--not real system
650 users) and that files owned by these users should not change ownership,
651 even if your system policy allows users other than root to edit them.
652
653 The default is 200; set the variable to nil to disable the feature.
654
655 +++
656 ** A block cursor can be drawn as wide as the glyph under it under X.
657
658 As an example: if a block cursor is over a tab character, it will be
659 drawn as wide as that tab on the display. To do this, set
660 `x-stretch-cursor' to a non-nil value.
661
662 +++
663 ** Empty display lines at the end of a buffer may be marked with a
664 bitmap (this is similar to the tilde displayed by vi).
665
666 This behavior is activated by setting the buffer-local variable
667 `indicate-empty-lines' to a non-nil value. The default value of this
668 variable is found in `default-indicate-empty-lines'.
669
670 +++
671 ** There is a new "aggressive" scrolling method.
672
673 When scrolling up because point is above the window start, if the
674 value of the buffer-local variable `scroll-up-aggessively' is a
675 number, Emacs chooses a new window start so that point ends up that
676 fraction of the window's height from the top of the window.
677
678 When scrolling down because point is below the window end, if the
679 value of the buffer-local variable `scroll-down-aggessively' is a
680 number, Emacs chooses a new window start so that point ends up that
681 fraction of the window's height from the bottom of the window.
682
683 ** The rectangle commands now avoid inserting undesirable spaces,
684 notably at the end of lines.
685
686 All these functions have been rewritten to avoid inserting unwanted
687 spaces, and an optional prefix now allows them to behave the old way.
688
689 +++
690 There is a new command M-x replace-rectangle.
691
692 ** The new command M-x query-replace-regexp-eval acts like
693 query-replace-regexp, but takes a Lisp expression which is evaluated
694 after each match to get the replacement text.
695
696 +++
697 ** M-x query-replace recognizes a new command `e' (or `E') that lets
698 you edit the replacement string.
699
700 ** The new command mail-abbrev-complete-alias, bound to `M-TAB', lets
701 you complete mail aliases in the text, analogous to
702 lisp-complete-symbol.
703
704 +++
705 ** Emacs now resizes mini-windows if appropriate.
706
707 If a message is longer than one line, or minibuffer contents are
708 longer than one line, Emacs now resizes the minibuffer window unless
709 it is on a frame of its own. You can control the maximum minibuffer
710 window size by setting the following variable:
711
712 - User option: max-mini-window-height
713
714 Maximum height for resizing mini-windows. If a float, it specifies a
715 fraction of the mini-window frame's height. If an integer, it
716 specifies a number of lines. If nil, don't resize.
717
718 Default is 0.25.
719
720 ** The command `Info-search' now uses a search history.
721
722 ** Changes to hideshow.el
723
724 Hideshow is now at version 5.x. It uses a new algorithms for block
725 selection and traversal, includes more isearch support, and has more
726 conventional keybindings.
727
728 *** Generalized block selection and traversal
729
730 A block is now recognized by three things: its start and end regexps
731 (both strings), and a match-data selector (an integer) specifying
732 which sub-expression in the start regexp serves as the place where a
733 `forward-sexp'-like function can operate. Hideshow always adjusts
734 point to this sub-expression before calling `hs-forward-sexp-func'
735 (which for most modes evaluates to `forward-sexp').
736
737 If the match-data selector is not specified, it defaults to zero,
738 i.e., the entire start regexp is valid, w/ no prefix. This is
739 backwards compatible with previous versions of hideshow. Please see
740 the docstring for variable `hs-special-modes-alist' for details.
741
742 *** Isearch support for updating mode line
743
744 During incremental search, if Hideshow minor mode is active, hidden
745 blocks are temporarily shown. The variable `hs-headline' records the
746 line at the beginning of the opened block (preceding the hidden
747 portion of the buffer), and the mode line is refreshed. When a block
748 is re-hidden, the variable is set to nil.
749
750 To show `hs-headline' in the mode line, you may wish to include
751 something like this in your .emacs.
752
753 (add-hook 'hs-minor-mode-hook
754 (lambda ()
755 (add-to-list 'mode-line-format 'hs-headline)))
756
757 *** New customization var: `hs-hide-all-non-comment-function'
758
759 Normally, `hs-hide-all' hides everything, leaving only the
760 header lines of top-level forms (and comments, unless var
761 `hs-hide-comments-when-hiding-all' is non-nil). It does this by
762 moving point to each top-level block beginning and hiding the
763 block there. In some major modes (for example, Java), this
764 behavior results in few blocks left visible, which may not be so
765 useful.
766
767 You can now set var `hs-hide-all-non-comment-function' to a
768 function to be called at each top-level block beginning, instead
769 of the normal block-hiding function. For example, the following
770 code defines a function to hide one level down and move point
771 appropriately, and then tells hideshow to use the new function.
772
773 (defun ttn-hs-hide-level-1 ()
774 (hs-hide-level 1)
775 (forward-sexp 1))
776 (setq hs-hide-all-non-comment-function 'ttn-hs-hide-level-1)
777
778 The name `hs-hide-all-non-comment-function' was chosen to
779 emphasize that this function is not called for comment blocks,
780 only for code blocks.
781
782 *** Command deleted: `hs-show-region'
783
784 Historical Note: This command was added to handle "unbalanced
785 parentheses" emergencies back when hideshow.el used selective
786 display for implementation.
787
788 *** Commands rebound to more conventional keys
789
790 The hideshow commands used to be bound to keys of the form "C-c
791 LETTER". This is contrary to the Emacs keybinding convention,
792 which reserves that space for user modification. Here are the
793 new bindings (which includes the addition of `hs-toggle-hiding'):
794
795 hs-hide-block C-c C-h
796 hs-show-block C-c C-s
797 hs-hide-all C-c C-M-h
798 hs-show-all C-c C-M-s
799 hs-hide-level C-c C-l
800 hs-toggle-hiding C-c C-c
801 hs-mouse-toggle-hiding [(shift button-2)]
802
803 These were chosen to roughly imitate those used by Outline mode.
804
805 ** Changes to Change Log mode and Add-Log functions
806
807 +++
808 *** If you invoke `add-change-log-entry' from a backup file, it makes
809 an entry appropriate for the file's parent. This is useful for making
810 log entries by comparing a version with deleted functions.
811
812 +++
813 **** New command M-x change-log-merge merges another log into the
814 current buffer.
815
816 +++
817 *** New command M-x change-log-redate fixes any old-style date entries
818 in a log file.
819
820 +++
821 *** Change Log mode now adds a file's version number to change log
822 entries if user-option `change-log-version-info-enabled' is non-nil.
823
824 +++
825 *** Unless the file is under version control the search for a file's
826 version number is performed based on regular expressions from
827 `change-log-version-number-regexp-list' which can be cutomized.
828 Version numbers are only found in the first 10 percent of a file.
829
830 *** Change Log mode now defines its own faces for font-lock
831 highlighting.
832
833 ** Changes in Font Lock
834
835 *** The new function `font-lock-remove-keywords' can be used to remove
836 font-lock keywords from the current buffer or from a specific major
837 mode.
838
839 ** Comint (subshell) changes
840
841 By default, comint no longer uses the variable `comint-prompt-regexp' to
842 distinguish prompts from user-input. Instead, it notices which parts of
843 the text were output by the process, and which entered by the user, and
844 attaches `field' properties to allow emacs commands to use this information.
845 Common movement commands, notably beginning-of-line, respect field
846 boundaries in a fairly natural manner.
847 To disable this feature, and use the old behavior, set the variable
848 `comint-use-prompt-regexp-instead-of-fields' to a non-nil value.
849
850 Comint now includes new features to send commands to running processes
851 and redirect the output to a designated buffer or buffers.
852
853 The command M-x comint-redirect-send-command reads a command and
854 buffer name from the mini-buffer. The command is sent to the current
855 buffer's process, and its output is inserted into the specified buffer.
856
857 The command M-x comint-redirect-send-command-to-process acts like
858 M-x comint-redirect-send-command but additionally reads the name of
859 the buffer whose process should be used from the mini-buffer.
860
861 Packages based on comint.el like shell-mode, and scheme-interaction-mode
862 now highlight user input and program prompts, and support choosing
863 previous input with mouse-2. To control these feature, see the
864 user-options `comint-highlight-input' and `comint-highlight-prompt'.
865
866 ** Changes to Rmail mode
867
868 *** The new user-option rmail-rmail-user-mail-address-regexp can be
869 set to fine tune the identification of of the correspondent when
870 receiving new mail. If it matches the address of the sender, the
871 recipient is taken as correspondent of a mail. If nil, the default,
872 `user-login-name' and `user-mail-address' are used to exclude yourself
873 as correspondent.
874
875 Usually you don't have to set this variable, except if you collect
876 mails sent by you under different user names. Then it should be a
877 regexp matching your mail addresses.
878
879 *** The new user-option rmail-confirm-expunge controls whether and how
880 to ask for confirmation before expunging deleted messages from an
881 Rmail file. You can choose between no confirmation, confirmation
882 with y-or-n-p, or confirmation with yes-or-no-p. Default is to ask
883 for confirmation with yes-or-no-p.
884
885 *** RET is now bound in the Rmail summary to rmail-summary-goto-msg,
886 like `j'.
887
888 *** There is a new user option `rmail-digest-end-regexps' that
889 specifies the regular expressions to detect the line that ends a
890 digest message.
891
892 *** The new user option `rmail-automatic-folder-directives' specifies
893 in which folder to put messages automatically.
894
895 ** Changes to TeX mode
896
897 The default mode has been changed from `plain-tex-mode' to
898 `latex-mode'.
899
900 ** Changes to RefTeX mode
901
902 *** RefTeX has new support for index generation. Index entries can be
903 created with `C-c <', with completion available on index keys.
904 Pressing `C-c /' indexes the word at the cursor with a default
905 macro. `C-c >' compiles all index entries into an alphabetically
906 sorted *Index* buffer which looks like the final index. Entries
907 can be edited from that buffer.
908
909 *** Label and citation key selection now allow to select several
910 items and reference them together (use `m' to mark items, `a' or
911 `A' to use all marked entries).
912
913 *** reftex.el has been split into a number of smaller files to reduce
914 memory use when only a part of RefTeX is being used.
915
916 *** a new command `reftex-view-crossref-from-bibtex' (bound to `C-c &'
917 in BibTeX-mode) can be called in a BibTeX database buffer in order
918 to show locations in LaTeX documents where a particular entry has
919 been cited.
920
921 ** Emacs Lisp mode now allows multiple levels of outline headings.
922 The level of a heading is determined from the number of leading
923 semicolons in a heading line. Toplevel forms starting with a `('
924 in column 1 are always made leaves.
925
926 ** The M-x time-stamp command (most commonly used on write-file-hooks)
927 has the following new features:
928
929 *** The patterns for finding the time stamp and for updating a pattern
930 may match text spanning multiple lines. For example, some people like
931 to have the filename and date on separate lines. The new variable
932 time-stamp-inserts-lines controls the matching for multi-line patterns.
933
934 *** More than one time stamp can be updated in the same file. This
935 feature is useful if you need separate time stamps in a program source
936 file to both include in formatted documentation and insert in the
937 compiled binary. The same time-stamp will be written at each matching
938 pattern. The variable time-stamp-count enables this new feature; it
939 defaults to 1.
940
941 ** Partial Completion mode now completes environment variables in
942 file names.
943
944 +++
945 ** Tooltips.
946
947 Tooltips are small X windows displaying a help string at the current
948 mouse position. To use them, use the Lisp package `tooltip' which you
949 can access via the user option `tooltip-mode'.
950
951 Tooltips also provides support for GUD debugging. If activated,
952 variable values can be displayed in tooltips by pointing at them with
953 the mouse in source buffers. You can customize various aspects of the
954 tooltip display in the group `tooltip'.
955
956 +++
957 ** Customize changes
958
959 *** Customize now supports comments about customized items. Use the
960 `State' menu to add comments. Note that customization comments will
961 cause the customizations to fail in earlier versions of Emacs.
962
963 *** The new option `custom-buffer-done-function' says whether to kill
964 Custom buffers when you've done with them or just bury them (the
965 default).
966
967 *** The keyword :set-after in defcustom allows to specify dependencies
968 between custom options. Example:
969
970 (defcustom default-input-method nil
971 "*Default input method for multilingual text (a string).
972 This is the input method activated automatically by the command
973 `toggle-input-method' (\\[toggle-input-method])."
974 :group 'mule
975 :type '(choice (const nil) string)
976 :set-after '(current-language-environment))
977
978 This specifies that default-input-method should be set after
979 current-language-environment even if default-input-method appears
980 first in a custom-set-variables statement.
981
982 ** New features in evaluation commands
983
984 *** The commands to evaluate Lisp expressions, such as C-M-x in Lisp
985 modes, C-j in Lisp Interaction mode, and M-:, now bind the variables
986 print-level, print-length, and debug-on-error based on the
987 customizable variables eval-expression-print-level,
988 eval-expression-print-length, and eval-expression-debug-on-error.
989
990 *** The function `eval-defun' (M-C-x) now loads Edebug and instruments
991 code when called with a prefix argument.
992
993 ** Ispell changes
994
995 +++
996 *** The command `ispell' now spell-checks a region if
997 transient-mark-mode is on, and the mark is active. Otherwise it
998 spell-checks the current buffer.
999
1000 +++
1001 *** Support for synchronous subprocesses - DOS/Windoze - has been
1002 added.
1003
1004 *** An "alignment error" bug was fixed when a manual spelling
1005 correction is made and re-checked.
1006
1007 *** An Italian and a Portuguese dictionary definition has been added.
1008
1009 *** Region skipping performance has been vastly improved in some
1010 cases.
1011
1012 *** Spell checking HTML buffers has been improved and isn't so strict
1013 on syntax errors.
1014
1015 *** The buffer-local words are now always placed on a new line at the
1016 end of the buffer.
1017
1018 ** Dired changes
1019
1020 *** New variable `dired-recursive-deletes' determines if the delete
1021 command will delete non-empty directories recursively. The default
1022 is, delete only empty directories.
1023
1024 *** New variable `dired-recursive-copies' determines if the copy
1025 command will copy directories recursively. The default is, do not
1026 copy directories recursively.
1027
1028 *** In command `dired-do-shell-command' (usually bound to `!') a `?'
1029 in the shell command has a special meaning similar to `*', but with
1030 the difference that the command will be run on each file individually.
1031
1032 *** The new command `dired-find-alternate-file' (usually bound to `a')
1033 replaces the Dired buffer with the buffer for an alternate file or
1034 directory.
1035
1036 *** The new command `dired-show-file-type' (usually bound to `w') shows
1037 a message in the echo area describing what type of file the point is on.
1038 This command invokes the external program `file' do its work, and so
1039 will only work on systems with that program, and will be only as
1040 accurate or inaccurate as it is.
1041
1042 *** Dired now properly handles undo changes of adding/removing `-R'
1043 from ls switches.
1044
1045 ** The variable mail-specify-envelope-from controls whether to
1046 use the -f option when sending mail.
1047
1048 ** CC mode changes.
1049
1050 Note: This release contains changes that might not be compatible with
1051 current user setups (although it's believed that these
1052 incompatibilities will only show in very uncommon circumstances).
1053 However, since the impact is uncertain, these changes may be rolled
1054 back depending on user feedback. Therefore there's no forward
1055 compatibility guarantee wrt the new features introduced in this
1056 release.
1057
1058 *** c-style-variables-are-local-p now defaults to t.
1059 This is an incompatible change that has been made to make the behavior
1060 of the style system wrt global variable settings less confusing for
1061 non-advanced users. If you know what this variable does you might
1062 want to set it to nil in your .emacs, otherwise you probably don't
1063 have to bother.
1064
1065 Defaulting c-style-variables-are-local-p to t avoids the confusing
1066 situation that occurs when a user sets some style variables globally
1067 and edits both a Java and a non-Java file in the same Emacs session.
1068 If the style variables aren't buffer local in this case, loading of
1069 the second file will cause the default style (either "gnu" or "java"
1070 by default) to override the global settings made by the user.
1071
1072 *** New initialization procedure for the style system.
1073 When the initial style for a buffer is determined by CC Mode (from the
1074 variable c-default-style), the global values of style variables now
1075 take precedence over the values specified by the chosen style. This
1076 is different than the old behavior: previously, the style-specific
1077 settings would override the global settings. This change makes it
1078 possible to do simple configuration in the intuitive way with
1079 Customize or with setq lines in one's .emacs file.
1080
1081 By default, the global value of every style variable is the new
1082 special symbol set-from-style, which causes the value to be taken from
1083 the style system. This means that in effect, only an explicit setting
1084 of a style variable will cause the "overriding" behavior described
1085 above.
1086
1087 Also note that global settings override style-specific settings *only*
1088 when the initial style of a buffer is chosen by a CC Mode major mode
1089 function. When a style is chosen in other ways --- for example, by a
1090 call like (c-set-style "gnu") in a hook, or via M-x c-set-style ---
1091 then the style-specific values take precedence over any global style
1092 values. In Lisp terms, global values override style-specific values
1093 only when the new second argument to c-set-style is non-nil; see the
1094 function documentation for more info.
1095
1096 The purpose of these changes is to make it easier for users,
1097 especially novice users, to do simple customizations with Customize or
1098 with setq in their .emacs files. On the other hand, the new system is
1099 intended to be compatible with advanced users' customizations as well,
1100 such as those that choose styles in hooks or whatnot. This new system
1101 is believed to be almost entirely compatible with current
1102 configurations, in spite of the changed precedence between style and
1103 global variable settings when a buffer's default style is set.
1104
1105 (Thanks to Eric Eide for clarifying this explanation a bit.)
1106
1107 **** c-offsets-alist is now a customizable variable.
1108 This became possible as a result of the new initialization behavior.
1109
1110 This variable is treated slightly differently from the other style
1111 variables; instead of using the symbol set-from-style, it will be
1112 completed with the syntactic symbols it doesn't already contain when
1113 the style is first initialized. This means it now defaults to the
1114 empty list to make all syntactic elements get their values from the
1115 style system.
1116
1117 **** Compatibility variable to restore the old behavior.
1118 In case your configuration doesn't work with this change, you can set
1119 c-old-style-variable-behavior to non-nil to get the old behavior back
1120 as far as possible.
1121
1122 *** Improvements to line breaking and text filling.
1123 CC Mode now handles this more intelligently and seamlessly wrt the
1124 surrounding code, especially inside comments. For details see the new
1125 chapter about this in the manual.
1126
1127 **** New variable to recognize comment line prefix decorations.
1128 The variable c-comment-prefix-regexp has been added to properly
1129 recognize the line prefix in both block and line comments. It's
1130 primarily used to initialize the various paragraph recognition and
1131 adaptive filling variables that the text handling functions uses.
1132
1133 **** New variable c-block-comment-prefix.
1134 This is a generalization of the now obsolete variable
1135 c-comment-continuation-stars to handle arbitrary strings.
1136
1137 **** CC Mode now uses adaptive fill mode.
1138 This to make it adapt better to the paragraph style inside comments.
1139
1140 It's also possible to use other adaptive filling packages inside CC
1141 Mode, notably Kyle E. Jones' Filladapt mode (http://wonderworks.com/).
1142 A new convenience function c-setup-filladapt sets up Filladapt for use
1143 inside CC Mode.
1144
1145 Note though that the 2.12 version of Filladapt lacks a feature that
1146 causes it to work suboptimally when c-comment-prefix-regexp can match
1147 the empty string (which it commonly does). A patch for that is
1148 available from the CC Mode web site (http://www.python.org/emacs/
1149 cc-mode/).
1150
1151 **** It's now possible to selectively turn off auto filling.
1152 The variable c-ignore-auto-fill is used to ignore auto fill mode in
1153 specific contexts, e.g. in preprocessor directives and in string
1154 literals.
1155
1156 **** New context sensitive line break function c-context-line-break.
1157 It works like newline-and-indent in normal code, and adapts the line
1158 prefix according to the comment style when used inside comments. If
1159 you're normally using newline-and-indent, you might want to switch to
1160 this function.
1161
1162 *** Fixes to IDL mode.
1163 It now does a better job in recognizing only the constructs relevant
1164 to IDL. E.g. it no longer matches "class" as the beginning of a
1165 struct block, but it does match the CORBA 2.3 "valuetype" keyword.
1166 Thanks to Eric Eide.
1167
1168 *** Improvements to the Whitesmith style.
1169 It now keeps the style consistently on all levels and both when
1170 opening braces hangs and when they don't.
1171
1172 **** New lineup function c-lineup-whitesmith-in-block.
1173
1174 *** New lineup functions c-lineup-template-args and c-indent-multi-line-block.
1175 See their docstrings for details. c-lineup-template-args does a
1176 better job of tracking the brackets used as parens in C++ templates,
1177 and is used by default to line up continued template arguments.
1178
1179 *** c-lineup-comment now preserves alignment with a comment on the
1180 previous line. It used to instead preserve comments that started in
1181 the column specified by comment-column.
1182
1183 *** c-lineup-C-comments handles "free form" text comments.
1184 In comments with a long delimiter line at the start, the indentation
1185 is kept unchanged for lines that start with an empty comment line
1186 prefix. This is intended for the type of large block comments that
1187 contain documentation with its own formatting. In these you normally
1188 don't want CC Mode to change the indentation.
1189
1190 *** The `c' syntactic symbol is now relative to the comment start
1191 instead of the previous line, to make integers usable as lineup
1192 arguments.
1193
1194 *** All lineup functions have gotten docstrings.
1195
1196 *** More preprocessor directive movement functions.
1197 c-down-conditional does the reverse of c-up-conditional.
1198 c-up-conditional-with-else and c-down-conditional-with-else are
1199 variants of these that also stops at "#else" lines (suggested by Don
1200 Provan).
1201
1202 *** Minor improvements to many movement functions in tricky situations.
1203
1204 ** Makefile mode changes
1205
1206 *** The mode now uses the abbrev table `makefile-mode-abbrev-table'.
1207
1208 *** Conditionals and include statements are now highlighted when
1209 Fontlock mode is active.
1210
1211 ** Isearch changes
1212
1213 *** Isearch now puts a call to `isearch-resume' in the command history,
1214 so that searches can be resumed.
1215
1216 *** In Isearch mode, M-C-s and M-C-r are now bound like C-s and C-r,
1217 respectively, i.e. you can repeat a regexp isearch with the same keys
1218 that started the search.
1219
1220 *** In Isearch mode, mouse-2 in the echo area now yanks the current
1221 selection into the search string rather than giving an error.
1222
1223 +++
1224 *** There is a new lazy highlighting feature in incremental search.
1225
1226 Lazy highlighting is switched on/off by customizing variable
1227 `isearch-lazy-highlight'. When active, all matches for the current
1228 search string are highlighted. The current match is highlighted as
1229 before using face `isearch' or `region'. All other matches are
1230 highlighted using face `isearch-lazy-highlight-face' which defaults to
1231 `secondary-selection'.
1232
1233 The extra highlighting makes it easier to anticipate where the cursor
1234 will end up each time you press C-s or C-r to repeat a pending search.
1235 Highlighting of these additional matches happens in a deferred fashion
1236 using "idle timers," so the cycles needed do not rob isearch of its
1237 usual snappy response.
1238
1239 If `isearch-lazy-highlight-cleanup' is set to t, highlights for
1240 matches are automatically cleared when you end the search. If it is
1241 set to nil, you can remove the highlights manually with `M-x
1242 isearch-lazy-highlight-cleanup'.
1243
1244 +++
1245 ** Changes in sort.el
1246
1247 The function sort-numeric-fields interprets numbers starting with `0'
1248 as octal and numbers starting with `0x' or `0X' as hexadecimal. The
1249 new user-option sort-numeric-base can be used to specify a default
1250 numeric base.
1251
1252 ** Changes to Ange-ftp
1253
1254 +++
1255 *** Ange-ftp allows you to specify of a port number in remote file
1256 names cleanly. It is appended to the host name, separated by a hash
1257 sign, e.g. `/foo@bar.org#666:mumble'. (This syntax comes from EFS.)
1258
1259 *** If the new user-option `ange-ftp-try-passive-mode' is set, passive
1260 ftp mode will be used if the ftp client supports that.
1261
1262 *** Ange-ftp handles the output of the w32-style clients which
1263 output ^M at the end of lines.
1264
1265 ** Shell script mode changes.
1266
1267 Shell script mode (sh-script) can now indent scripts for shells
1268 derived from sh and rc. The indentation style is customizeable, and
1269 sh-script can attempt to "learn" the current buffer's style.
1270
1271 ** Etags changes.
1272
1273 *** In DOS, etags looks for file.cgz if it cannot find file.c.
1274
1275 *** New option --ignore-case-regex is an alternative to --regex. It is now
1276 possible to bind a regexp to a language, by prepending the regexp with
1277 {lang}, where lang is one of the languages that `etags --help' prints out.
1278 This feature is useful especially for regex files, where each line contains
1279 a regular expression. The manual contains details.
1280
1281 *** In C and derived languages, etags creates tags for function
1282 declarations when given the --declarations option.
1283
1284 *** In C++, tags are created for "operator". The tags have the form
1285 "operator+", without spaces between the keyword and the operator.
1286
1287 *** New language Ada: tags are functions, procedures, packages, tasks, and
1288 types.
1289
1290 *** In Fortran, `procedure' is not tagged.
1291
1292 *** In Java, tags are created for "interface".
1293
1294 *** In Lisp, "(defstruct (foo", "(defun (operator" and similar constructs
1295 are now tagged.
1296
1297 *** In Perl, the --globals option tags global variables. my and local
1298 variables are tagged.
1299
1300 *** New language Python: def and class at the beginning of a line are tags.
1301
1302 *** .ss files are Scheme files, .pdb is Postscript with C syntax, .psw is
1303 for PSWrap.
1304
1305 +++
1306 ** Changes in etags.el
1307
1308 *** The new user-option tags-case-fold-search can be used to make
1309 tags operations case-sensitive or case-insensitive. The default
1310 is to use the same setting as case-fold-search.
1311
1312 *** You can display additional output with M-x tags-apropos by setting
1313 the new variable tags-apropos-additional-actions.
1314
1315 If non-nil, the variable's value should be a list of triples (TITLE
1316 FUNCTION TO-SEARCH). For each triple, M-x tags-apropos processes
1317 TO-SEARCH and lists tags from it. TO-SEARCH should be an alist,
1318 obarray, or symbol. If it is a symbol, the symbol's value is used.
1319
1320 TITLE is a string to use to label the list of tags from TO-SEARCH.
1321
1322 FUNCTION is a function to call when an entry is selected in the Tags
1323 List buffer. It is called with one argument, the selected symbol.
1324
1325 A useful example value for this variable might be something like:
1326
1327 '(("Emacs Lisp" Info-goto-emacs-command-node obarray)
1328 ("Common Lisp" common-lisp-hyperspec common-lisp-hyperspec-obarray)
1329 ("SCWM" scwm-documentation scwm-obarray))
1330
1331 *** The face tags-tag-face can be used to customize the appearance
1332 of tags in the output of M-x tags-apropos.
1333
1334 *** Setting tags-apropos-verbose to a non-nil value displays the
1335 names of tags files in the *Tags List* buffer.
1336
1337 +++
1338 ** Emacs now attempts to determine the initial language environment
1339 and preferred and locale coding systems systematically from the
1340 LC_ALL, LC_CTYPE, and LANG environment variables during startup.
1341
1342 +++
1343 ** New language environments `Polish', `Latin-8' and `Latin-9'.
1344 Latin-8 and Latin-9 correspond respectively to the ISO character sets
1345 8859-14 (Celtic) and 8859-15 (updated Latin-1, with the Euro sign).
1346 GNU Intlfonts doesn't support these yet; there are basic 8859-14 and
1347 8859-15 fonts at <URL:http://czyborra.com/charsets/> and recent X
1348 releases have 8859-15. There are new Latin-8 and Latin-9 prefix
1349 (only) and Polish slash input methods in Leim.
1350
1351 +++
1352 ** Fortran mode has a new command `fortran-strip-sequence-nos' to
1353 remove text past column 72. The syntax class of `\' in Fortran is now
1354 appropriate for C-style escape sequences in strings.
1355
1356 ** SGML mode's default `sgml-validate-command' is now `nsgmls'.
1357
1358 +++
1359 ** A new command `view-emacs-problems' (C-h P) displays the PROBLEMS file.
1360
1361 +++
1362 ** The Dabbrev package has a new user-option `dabbrev-ignored-regexps'
1363 containing a list of regular expressions. Buffers matching a regular
1364 expression from that list, are not checked.
1365
1366 ** Emacs can now figure out modification times of remote files.
1367 When you do C-x C-f /user@host:/path/file RET and edit the file,
1368 and someone else modifies the file, you will be prompted to revert
1369 the buffer, just like for the local files.
1370
1371 ** The buffer menu (C-x C-b) no longer lists the *Buffer List* buffer.
1372
1373 +++
1374 ** When invoked with a prefix argument, the command `list-abbrevs' now
1375 displays local abbrevs, only.
1376
1377 ** VC Changes
1378
1379 VC has been overhauled internally. It is now modular, making it
1380 easier to plug-in arbitrary version control backends. (See Lisp
1381 Changes for details on the new structure.) As a result, the mechanism
1382 to enable and disable support for particular version systems has
1383 changed: everything is now controlled by the new variable
1384 `vc-handled-backends'. Its value is a list of atoms that identify
1385 version systems; the default is '(RCS CVS SCCS). When finding a file,
1386 each of the backends in that list is tried in order to see whether the
1387 file is registered in that backend.
1388
1389 When registering a new file, VC first tries each of the listed
1390 backends to see if any of them considers itself "responsible" for the
1391 directory of the file (e.g. because a corresponding subdirectory for
1392 master files exists). If none of the backends is responsible, then
1393 the first backend in the list that could register the file is chosen.
1394 As a consequence, the variable `vc-default-back-end' is now obsolete.
1395
1396 The old variable `vc-master-templates' is also obsolete, although VC
1397 still supports it for backward compatibility. To define templates for
1398 RCS or SCCS, you should rather use the new variables
1399 vc-{rcs,sccs}-master-templates. (There is no such feature under CVS
1400 where it doesn't make sense.)
1401
1402 The variables `vc-ignore-vc-files' and `vc-handle-cvs' are also
1403 obsolete now, you must set `vc-handled-backends' to nil or exclude
1404 `CVS' from the list, respectively, to achieve their effect now.
1405
1406 *** General Changes
1407
1408 The variable `vc-checkout-carefully' is obsolete: the corresponding
1409 checks are always done now.
1410
1411 VC Dired buffers are now kept up-to-date during all version control
1412 operations.
1413
1414 *** Changes for CVS
1415
1416 There is a new user option, `vc-cvs-stay-local'. If it is `t' (the
1417 default), then VC avoids network queries for files registered in
1418 remote repositories. The state of such files is then only determined
1419 by heuristics and past information. `vc-cvs-stay-local' can also be a
1420 regexp to match against repository hostnames; only files from hosts
1421 that match it are treated locally. If the variable is nil, then VC
1422 queries the repository just as often as it does for local files.
1423
1424 If `vc-cvs-stay-local' is on, and there have been changes in the
1425 repository, VC notifies you about it when you actually try to commit.
1426 If you want to check for updates from the repository without trying to
1427 commit, you can either use C-u C-x v m to perform an update on the
1428 current file, or you can use C-x v r RET to get an update for an
1429 entire directory tree.
1430
1431 The new user option `vc-cvs-use-edit' indicates whether VC should call
1432 "cvs edit" to make files writeable; it defaults to `t'. (This option
1433 is only meaningful if the CVSREAD variable is set, or if files are
1434 "watched" by other developers.)
1435
1436 *** Lisp Changes in VC
1437
1438 VC has been restructured internally to make it modular. You can now
1439 add support for arbitrary version control backends by writing a
1440 library that provides a certain set of backend-specific functions, and
1441 then telling VC to use that library. For example, to add support for
1442 a version system named FOO, you write a library named vc-foo.el, which
1443 provides a number of functions vc-foo-... (see commentary at the end
1444 of vc.el for a detailed list of them). To make VC use that library,
1445 you need to put it somewhere into Emacs' load path and add the atom
1446 `FOO' to the list `vc-handled-backends'.
1447
1448 ** New modes and packages
1449
1450 +++
1451 *** The new package timeclock.el is a mode is for keeping track of time
1452 intervals. You can use it for whatever purpose you like, but the
1453 typical scenario is to keep track of how much time you spend working
1454 on certain projects.
1455
1456 +++
1457 *** The new package hi-lock.el, text matching interactively entered
1458 regexp's can be highlighted. For example,
1459
1460 M-x highlight-regexp RET clearly RET RET
1461
1462 will highlight all occurrences of `clearly' using a yellow background
1463 face. New occurrences of `clearly' will be highlighted as they are
1464 typed. `M-x unhighlight-regexp RET' will remove the highlighting.
1465 Any existing face can be used for highlighting and a set of
1466 appropriate faces is provided. The regexps can be written into the
1467 current buffer in a form that will be recognized the next time the
1468 corresponding file is read.
1469
1470 +++
1471 *** The new package zone.el plays games with Emacs' display when
1472 Emacs is idle.
1473
1474 *** The new package xml.el provides a simple but generic XML
1475 parser. It doesn't parse the DTDs however.
1476
1477 *** The comment operations are now provided by the newcomment.el
1478 package which allows different styles of comment-region and should
1479 be more robust while offering the same functionality.
1480
1481 +++
1482 *** The Ebrowse package implements a C++ class browser and tags
1483 facilities tailored for use with C++. It is documented in a
1484 separate Texinfo file.
1485
1486 +++
1487 *** The PCL-CVS package available by either running M-x cvs-examine or
1488 by visiting a CVS administrative directory (with a prefix argument)
1489 provides an alternative interface to VC-dired for CVS. It comes with
1490 `log-view-mode' to view RCS and SCCS logs and `log-edit-mode' used to
1491 enter checkin log messages.
1492
1493 +++
1494 *** The new package called `woman' allows to browse Unix man pages
1495 without invoking external programs.
1496
1497 The command `M-x woman' formats manual pages entirely in Emacs Lisp
1498 and then displays them, like `M-x manual-entry' does. Unlike
1499 `manual-entry', `woman' does not invoke any external programs, so it
1500 is useful on systems such as MS-DOS/MS-Windows where the `man' and
1501 Groff or `troff' commands are not readily available.
1502
1503 The command `M-x woman-find-file' asks for the file name of a man
1504 page, then formats and displays it like `M-x woman' does.
1505
1506 +++
1507 *** The new command M-x re-builder offers a convenient interface for
1508 authoring regular expressions with immediate visual feedback.
1509
1510 The buffer from which the command was called becomes the target for
1511 the regexp editor popping up in a separate window. Matching text in
1512 the target buffer is immediately color marked during the editing.
1513 Each sub-expression of the regexp will show up in a different face so
1514 even complex regexps can be edited and verified on target data in a
1515 single step.
1516
1517 On displays not supporting faces the matches instead blink like
1518 matching parens to make them stand out. On such a setup you will
1519 probably also want to use the sub-expression mode when the regexp
1520 contains such to get feedback about their respective limits.
1521
1522 +++
1523 *** glasses-mode is a minor mode that makes
1524 unreadableIdentifiersLikeThis readable. It works as glasses, without
1525 actually modifying content of a buffer.
1526
1527 *** The package ebnf2ps translates an EBNF to a syntactic chart in
1528 PostScript.
1529
1530 Currently accepts ad-hoc EBNF, ISO EBNF and Bison/Yacc.
1531
1532 The ad-hoc default EBNF syntax has the following elements:
1533
1534 ; comment (until end of line)
1535 A non-terminal
1536 "C" terminal
1537 ?C? special
1538 $A default non-terminal
1539 $"C" default terminal
1540 $?C? default special
1541 A = B. production (A is the header and B the body)
1542 C D sequence (C occurs before D)
1543 C | D alternative (C or D occurs)
1544 A - B exception (A excluding B, B without any non-terminal)
1545 n * A repetition (A repeats n (integer) times)
1546 (C) group (expression C is grouped together)
1547 [C] optional (C may or not occurs)
1548 C+ one or more occurrences of C
1549 {C}+ one or more occurrences of C
1550 {C}* zero or more occurrences of C
1551 {C} zero or more occurrences of C
1552 C / D equivalent to: C {D C}*
1553 {C || D}+ equivalent to: C {D C}*
1554 {C || D}* equivalent to: [C {D C}*]
1555 {C || D} equivalent to: [C {D C}*]
1556
1557 Please, see ebnf2ps documentation for EBNF syntax and how to use it.
1558
1559 *** The package align.el will align columns within a region, using M-x
1560 align. Its mode-specific rules, based on regular expressions,
1561 determine where the columns should be split. In C and C++, for
1562 example, it will align variable names in declaration lists, or the
1563 equal signs of assignments.
1564
1565 +++
1566 *** `paragraph-indent-minor-mode' is a new minor mode supporting
1567 paragraphs in the same style as `paragraph-indent-text-mode'.
1568
1569 +++
1570 *** bs.el is a new package for buffer selection similar to
1571 list-buffers or electric-buffer-list. Use M-x bs-show to display a
1572 buffer menu with this package. You can use M-x bs-customize to
1573 customize the package.
1574
1575 *** find-lisp.el is a package emulating the Unix find command in Lisp.
1576
1577 *** calculator.el is a small calculator package that is intended to
1578 replace desktop calculators such as xcalc and calc.exe. Actually, it
1579 is not too small - it has more features than most desktop calculators,
1580 and can be customized easily to get many more functions. It should
1581 not be confused with "calc" which is a much bigger mathematical tool
1582 which answers different needs.
1583
1584 +++
1585 *** The minor modes cwarn-mode and global-cwarn-mode highlights
1586 suspicious C and C++ constructions. Currently, assignments inside
1587 expressions, semicolon following `if', `for' and `while' (except, of
1588 course, after a `do .. while' statement), and C++ functions with
1589 reference parameters are recognized. The modes require font-lock mode
1590 to be enabled.
1591
1592 +++
1593 *** smerge-mode.el provides `smerge-mode', a simple minor-mode for files
1594 containing diff3-style conflict markers, such as generated by RCS.
1595
1596 +++
1597 *** 5x5.el is a simple puzzle game.
1598
1599 +++
1600 *** hl-line.el provides a minor mode to highlight the current line.
1601
1602 *** ansi-color.el translates ANSI terminal escapes into text-properties.
1603
1604 Please note: if `ansi-color-for-shell-mode' and
1605 `global-font-lock-mode' are non-nil, loading ansi-color.el will
1606 disable font-lock and add `ansi-color-apply' to
1607 `comint-preoutput-filter-functions' for all shell-mode buffers. This
1608 displays the output of "ls --color=yes" using the correct foreground
1609 and background colors.
1610
1611 *** delphi.el provides a major mode for editing the Delphi (Object
1612 Pascal) language.
1613
1614 +++
1615 *** quickurl.el provides a simple method of inserting a URL based on
1616 the text at point.
1617
1618 *** sql.el provides an interface to SQL data bases.
1619
1620 +++
1621 *** fortune.el uses the fortune program to create mail/news signatures.
1622
1623 *** whitespace.el ???
1624
1625 *** PostScript mode (ps-mode) is a new major mode for editing PostScript
1626 files. It offers: interaction with a PostScript interpreter, including
1627 (very basic) error handling; fontification, easily customizable for
1628 interpreter messages; auto-indentation; insertion of EPSF templates and
1629 often used code snippets; viewing of BoundingBox; commenting out /
1630 uncommenting regions; conversion of 8bit characters to PostScript octal
1631 codes. All functionality is accessible through a menu.
1632
1633 *** delim-col helps to prettify columns in a text region or rectangle.
1634
1635 Here is an example of columns:
1636
1637 horse apple bus
1638 dog pineapple car EXTRA
1639 porcupine strawberry airplane
1640
1641 Doing the following settings:
1642
1643 (setq delimit-columns-str-before "[ ")
1644 (setq delimit-columns-str-after " ]")
1645 (setq delimit-columns-str-separator ", ")
1646 (setq delimit-columns-separator "\t")
1647
1648
1649 Selecting the lines above and typing:
1650
1651 M-x delimit-columns-region
1652
1653 It results:
1654
1655 [ horse , apple , bus , ]
1656 [ dog , pineapple , car , EXTRA ]
1657 [ porcupine, strawberry, airplane, ]
1658
1659 delim-col has the following options:
1660
1661 delimit-columns-str-before Specify a string to be inserted
1662 before all columns.
1663
1664 delimit-columns-str-separator Specify a string to be inserted
1665 between each column.
1666
1667 delimit-columns-str-after Specify a string to be inserted
1668 after all columns.
1669
1670 delimit-columns-separator Specify a regexp which separates
1671 each column.
1672
1673 delim-col has the following commands:
1674
1675 delimit-columns-region Prettify all columns in a text region.
1676 delimit-columns-rectangle Prettify all columns in a text rectangle.
1677
1678 +++
1679 *** The package recentf.el maintains a menu for visiting files that
1680 were operated on recently.
1681
1682 M-x recentf-mode RET toggles recentf mode.
1683
1684 M-x customize-variable RET recentf-mode RET can be used to enable
1685 recentf at Emacs startup.
1686
1687 M-x customize-variable RET recentf-menu-filter RET to specify a menu
1688 filter function to change the menu appearance. For example, the recent
1689 file list can be displayed:
1690
1691 - organized by major modes, directories or user defined rules.
1692 - sorted by file pathes, file names, ascending or descending.
1693 - showing pathes relative to the current default-directory
1694
1695 The `recentf-filter-changer' menu filter function allows to
1696 dynamically change the menu appearance.
1697
1698 *** elide-head.el provides a mechanism for eliding boilerplate header
1699 text.
1700
1701 +++
1702 *** footnote.el provides `footnote-mode', a minor mode supporting use
1703 of footnotes. It is intended for use with Message mode, but isn't
1704 specific to Message mode.
1705
1706 +++
1707 *** diff-mode.el provides `diff-mode', a major mode for
1708 viewing/editing context diffs (patches). It is selected for files
1709 with extension `.diff', `.diffs', `.patch' and `.rej'.
1710
1711 +++
1712 *** EUDC, the Emacs Unified Directory Client, provides a common user
1713 interface to access directory servers using different directory
1714 protocols. It has a separate manual.
1715
1716 *** autoconf.el provides a major mode for editing configure.in files
1717 for Autoconf, selected automatically.
1718
1719 +++
1720 *** windmove.el provides moving between windows.
1721
1722 *** crm.el provides a facility to read multiple strings from the
1723 minibuffer with completion.
1724
1725 *** todo-mode.el provides management of TODO lists and integration
1726 with the diary features.
1727
1728 *** autoarg.el provides a feature reported from Twenex Emacs whereby
1729 numeric keys supply prefix args rather than self inserting.
1730
1731 *** The function `turn-off-auto-fill' unconditionally turns off Auto
1732 Fill mode.
1733
1734 *** gnus-mule.el is now just a compatibility layer over the built-in
1735 Gnus facilities.
1736
1737 ** Withdrawn packages
1738
1739 *** mldrag.el has been removed. mouse.el provides the same
1740 functionality with aliases for the mldrag functions.
1741
1742 *** eval-reg.el has been obsoleted by changes to edebug.el and removed.
1743
1744 *** ph.el has been obsoleted by EUDC and removed.
1745
1746 \f
1747 * Lisp changes made after edition 2.6 of the Emacs Lisp Manual,
1748 (Display-related features are described in a page of their own below.)
1749
1750 +++
1751 ** The new function `display-message-or-buffer' displays a message in
1752 the echo area or pops up a buffer, depending on the length of the
1753 message.
1754
1755 ** The new macro `with-auto-compression-mode' allows evaluating an
1756 expression with auto-compression-mode enabled.
1757
1758 ** In image specifications, `:heuristic-mask' has been replaced
1759 with the more general `:mask' property.
1760
1761 ** Image specifications accept more `:algorithm's.
1762
1763 ** A `?' can be used in a symbol name without escaping it with a
1764 backslash.
1765
1766 +++
1767 ** Reading from the mini-buffer now reads from standard input if Emacs
1768 is running in batch mode. For example,
1769
1770 (message "%s" (read t))
1771
1772 will read a Lisp expression from standard input and print the result
1773 to standard output.
1774
1775 +++
1776 ** The argument of `down-list', `backward-up-list', `up-list',
1777 `kill-sexp', `backward-kill-sexp' and `mark-sexp' is now optional.
1778
1779 ** If `display-buffer-reuse-frames' is set, function `display-buffer'
1780 will raise frames displaying a buffer, instead of creating a new
1781 frame or window.
1782
1783 +++
1784 ** Two new functions for removing elements from lists/sequences
1785 were added
1786
1787 - Function: remove ELT SEQ
1788
1789 Return a copy of SEQ with all occurences of ELT removed. SEQ must be
1790 a list, vector, or string. The comparison is done with `equal'.
1791
1792 - Function: remq ELT LIST
1793
1794 Return a copy of LIST with all occurences of ELT removed. The
1795 comparison is done with `eq'.
1796
1797 ** The function `delete' now also works with vectors and strings.
1798
1799 ** The meaning of the `:weakness WEAK' argument of make-hash-table
1800 has been changed.
1801
1802 +++
1803 ** Function `aset' stores any multibyte character in any string
1804 without signaling "Attempt to change char length of a string". It may
1805 convert a unibyte string to multibyte if necessary.
1806
1807 ** The value of the `help-echo' text property is called as a function
1808 or evaluated, if it is not a string already, to obtain a help string.
1809
1810 ** Function `make-obsolete' now has an optional arg to say when the
1811 function was declared obsolete.
1812
1813 ** Function `plist-member' is renamed from `widget-plist-member' (which is
1814 retained as an alias).
1815
1816 ** Easy-menu's :filter now works as in XEmacs.
1817 It takes the unconverted (i.e. XEmacs) form of the menu and the result
1818 is automatically converted to Emacs' form.
1819
1820 ** The new function `window-list' has been defined
1821
1822 - Function: window-list &optional WINDOW MINIBUF ALL-FRAMES
1823
1824 Return a list of windows in canonical order. The parameters WINDOW,
1825 MINIBUF and ALL-FRAMES are defined like for `next-window'.
1826
1827 ** There's a new function `some-window' defined as follows
1828
1829 - Function: some-window PREDICATE &optional MINIBUF ALL-FRAMES DEFAULT
1830
1831 Return a window satisfying PREDICATE.
1832
1833 This function cycles through all visible windows using `walk-windows',
1834 calling PREDICATE on each one. PREDICATE is called with a window as
1835 argument. The first window for which PREDICATE returns a non-nil
1836 value is returned. If no window satisfies PREDICATE, DEFAULT is
1837 returned.
1838
1839 Optional second arg MINIBUF t means count the minibuffer window even
1840 if not active. MINIBUF nil or omitted means count the minibuffer iff
1841 it is active. MINIBUF neither t nor nil means not to count the
1842 minibuffer even if it is active.
1843
1844 Several frames may share a single minibuffer; if the minibuffer
1845 counts, all windows on all frames that share that minibuffer count
1846 too. Therefore, if you are using a separate minibuffer frame
1847 and the minibuffer is active and MINIBUF says it counts,
1848 `walk-windows' includes the windows in the frame from which you
1849 entered the minibuffer, as well as the minibuffer window.
1850
1851 ALL-FRAMES is the optional third argument.
1852 ALL-FRAMES nil or omitted means cycle within the frames as specified above.
1853 ALL-FRAMES = `visible' means include windows on all visible frames.
1854 ALL-FRAMES = 0 means include windows on all visible and iconified frames.
1855 ALL-FRAMES = t means include windows on all frames including invisible frames.
1856 If ALL-FRAMES is a frame, it means include windows on that frame.
1857 Anything else means restrict to the selected frame.
1858
1859 ** The function `single-key-description' now encloses function key and
1860 event names in angle brackets. When called with a second optional
1861 argument non-nil, angle brackets won't be printed.
1862
1863 ** If the variable `message-truncate-lines' is bound to t around a
1864 call to `message', the echo area will not be resized to display that
1865 message; it will be truncated instead, as it was done in 20.x.
1866 Default value is nil.
1867
1868 ** The user option `line-number-display-limit' can now be set to nil,
1869 meaning no limit.
1870
1871 ** `select-safe-coding-system' now also checks the most preferred
1872 coding-system if buffer-file-coding-system is `undecided' and
1873 DEFAULT-CODING-SYSTEM is not specified,
1874
1875 ** The function `subr-arity' provides information on the argument list
1876 of a primitive.
1877
1878 ** The text property `keymap' specifies a key map which overrides the
1879 buffer's local map and the map specified by the `local-map' property.
1880 This is probably what most current uses of `local-map' want, rather
1881 than replacing the local map.
1882
1883 ** The obsolete variables before-change-function and
1884 after-change-function are no longer acted upon and have been removed.
1885
1886 ** The function `apropos-mode' runs the hook `apropos-mode-hook'.
1887
1888 +++
1889 ** `concat' no longer accepts individual integer arguments, as
1890 promised long ago.
1891
1892 ** The new function `float-time' returns the current time as a float.
1893 \f
1894 * Lisp changes in Emacs 21.1 (see following page for display-related features)
1895
1896 Note that +++ before an item means the Lisp manual has been updated.
1897 --- means that I have decided it does not need to be in the Lisp manual.
1898 When you add a new item, please add it without either +++ or ---
1899 so I will know I still need to look at it -- rms.
1900
1901 *** The special form `save-restriction' now works correctly even if the
1902 buffer is widened inside the save-restriction and changes made outside
1903 the original restriction. Previously, doing this would cause the saved
1904 restriction to be restored incorrectly.
1905
1906 *** The functions `find-charset-region' and `find-charset-string' include
1907 `eight-bit-control' and/or `eight-bit-graphic' in the returned list
1908 when it finds 8-bit characters. Previously, it included `ascii' in a
1909 multibyte buffer and `unknown' in a unibyte buffer.
1910
1911 *** The functions `set-buffer-modified', `string-as-multibyte' and
1912 `string-as-unibyte' change the byte sequence of a buffer if it
1913 contains a character from the `eight-bit-control' character set.
1914
1915 *** The handling of multibyte sequences in a multibyte buffer is
1916 changed. Previously, a byte sequence matching the pattern
1917 [\200-\237][\240-\377]+ was interpreted as a single character
1918 regardless of the length of the trailing bytes [\240-\377]+. Thus, if
1919 the sequence was longer than what the leading byte indicated, the
1920 extra trailing bytes were ignored by Lisp functions. Now such extra
1921 bytes are independent 8-bit characters belonging to the charset
1922 eight-bit-graphic.
1923
1924 ** Fontsets are now implemented using char-tables.
1925
1926 A fontset can now be specified for for each independent character, for
1927 a group of characters or for a character set rather than just for a
1928 character set as previously.
1929
1930 *** The arguments of the function `set-fontset-font' are changed.
1931 They are NAME, CHARACTER, FONTNAME, and optional FRAME. The function
1932 modifies fontset NAME to use FONTNAME for CHARACTER.
1933
1934 CHARACTER may be a cons (FROM . TO), where FROM and TO are non-generic
1935 characters. In that case FONTNAME is used for all characters in the
1936 range FROM and TO (inclusive). CHARACTER may be a charset. In that
1937 case FONTNAME is used for all character in the charset.
1938
1939 FONTNAME may be a cons (FAMILY . REGISTRY), where FAMILY is the family
1940 name of a font and REGSITRY is a registry name of a font.
1941
1942 *** Variable x-charset-registry has been deleted. The default charset
1943 registries of character sets are set in the default fontset
1944 "fontset-default".
1945
1946 *** The function `create-fontset-from-fontset-spec' ignores the second
1947 argument STYLE-VARIANT. It never creates style-variant fontsets.
1948
1949 ** The method of composing characters is changed. Now character
1950 composition is done by a special text property `composition' in
1951 buffers and strings.
1952
1953 *** Charset composition is deleted. Emacs never creates a `composite
1954 character' which is an independent character with a unique character
1955 code. Thus the following functions handling `composite characters'
1956 have been deleted: composite-char-component,
1957 composite-char-component-count, composite-char-composition-rule,
1958 composite-char-composition-rule and decompose-composite-char delete.
1959 The variables leading-code-composition and min-composite-char have
1960 also been deleted.
1961
1962 *** Three more glyph reference points are added. They can be used to
1963 specify a composition rule. See the documentation of the variable
1964 `reference-point-alist' for more detail.
1965
1966 *** The function `compose-region' takes new arguments COMPONENTS and
1967 MODIFICATION-FUNC. With COMPONENTS, you can specify not only a
1968 composition rule but also characters to be composed. Such characters
1969 may differ between buffer and string text.
1970
1971 *** The function `compose-string' takes new arguments START, END,
1972 COMPONENTS, and MODIFICATION-FUNC.
1973
1974 *** The function `compose-string' puts text property `composition'
1975 directly on the argument STRING instead of returning a new string.
1976 Likewise, the function `decompose-string' just removes text property
1977 `composition' from STRING.
1978
1979 *** The new function `find-composition' returns information about
1980 a composition at a specified position in a buffer or a string.
1981
1982 *** The function `decompose-composite-char' is now labeled as
1983 obsolete.
1984
1985 ** The new character set `mule-unicode-0100-24ff' is introduced for
1986 Unicode characters of the range U+0100..U+24FF. Currently, this
1987 character set is not used.
1988
1989 ** The new character sets `japanese-jisx0213-1' and
1990 `japanese-jisx0213-2' are introduced for the new Japanese standard JIS
1991 X 0213 Plane 1 and Plane 2.
1992
1993 +++
1994 ** The new character sets `eight-bit-control' and `eight-bit-graphic'
1995 are introduced for 8-bit characters in the ranges 0x80..0x9F and
1996 0xA0..0xFF respectively.
1997
1998 +++
1999 ** If the APPEND argument of `write-region' is an integer, it seeks to
2000 that offset in the file before writing.
2001
2002 ** The function `add-minor-mode' has been added for convenience and
2003 compatibility with XEmacs (and is used internally by define-minor-mode).
2004
2005 ** The function `shell-command' now sets the default directory of the
2006 `*Shell Command Output*' buffer to the default directory of the buffer
2007 from which the command was issued.
2008
2009 ** The functions `query-replace', `query-replace-regexp',
2010 `query-replace-regexp-eval' `map-query-replace-regexp',
2011 `replace-string', `replace-regexp', and `perform-replace' take two
2012 additional optional arguments START and END that specify the region to
2013 operate on.
2014
2015 ** The new function `count-screen-lines' is a more flexible alternative
2016 to `window-buffer-height'.
2017
2018 - Function: count-screen-lines &optional BEG END COUNT-FINAL-NEWLINE WINDOW
2019
2020 Return the number of screen lines in the region between BEG and END.
2021 The number of screen lines may be different from the number of actual
2022 lines, due to line breaking, display table, etc.
2023
2024 Optional arguments BEG and END default to `point-min' and `point-max'
2025 respectively.
2026
2027 If region ends with a newline, ignore it unless optinal third argument
2028 COUNT-FINAL-NEWLINE is non-nil.
2029
2030 The optional fourth argument WINDOW specifies the window used for
2031 obtaining parameters such as width, horizontal scrolling, and so
2032 on. The default is to use the selected window's parameters.
2033
2034 Like `vertical-motion', `count-screen-lines' always uses the current
2035 buffer, regardless of which buffer is displayed in WINDOW. This makes
2036 possible to use `count-screen-lines' in any buffer, whether or not it
2037 is currently displayed in some window.
2038
2039 ** The new function `mapc' is like `mapcar' but doesn't collect the
2040 argument function's results.
2041
2042 ** The functions base64-decode-region and base64-decode-string now
2043 signal an error instead of returning nil if decoding fails.
2044
2045 ** The function sendmail-user-agent-compose now recognizes a `body'
2046 header in the list of headers passed to it.
2047
2048 ** The new function member-ignore-case works like `member', but
2049 ignores differences in case and text representation.
2050
2051 ** The buffer-local variable cursor-type can be used to specify the
2052 cursor to use in windows displaying a buffer. Values are interpreted
2053 as follows:
2054
2055 t use the cursor specified for the frame (default)
2056 nil don't display a cursor
2057 `bar' display a bar cursor with default width
2058 (bar . WIDTH) display a bar cursor with width WIDTH
2059 others display a box cursor.
2060
2061 ** The variable open-paren-in-column-0-is-defun-start controls whether
2062 an open parenthesis in column 0 is considered to be the start of a
2063 defun. If set, the default, it is considered a defun start. If not
2064 set, an open parenthesis in column 0 has no special meaning.
2065
2066 ** The new function `string-to-syntax' can be used to translate syntax
2067 specifications in string form as accepted by `modify-syntax-entry' to
2068 the cons-cell form that is used for the values of the `syntax-table'
2069 text property, and in `font-lock-syntactic-keywords'.
2070
2071 Example:
2072
2073 (string-to-syntax "()")
2074 => (4 . 41)
2075
2076 ** Emacs' reader supports CL read syntax for integers in bases
2077 other than 10.
2078
2079 *** `#BINTEGER' or `#bINTEGER' reads INTEGER in binary (radix 2).
2080 INTEGER optionally contains a sign.
2081
2082 #b1111
2083 => 15
2084 #b-1111
2085 => -15
2086
2087 *** `#OINTEGER' or `#oINTEGER' reads INTEGER in octal (radix 8).
2088
2089 #o666
2090 => 438
2091
2092 *** `#XINTEGER' or `#xINTEGER' reads INTEGER in hexadecimal (radix 16).
2093
2094 #xbeef
2095 => 48815
2096
2097 *** `#RADIXrINTEGER' reads INTEGER in radix RADIX, 2 <= RADIX <= 36.
2098
2099 #2R-111
2100 => -7
2101 #25rah
2102 => 267
2103
2104 ** The function `documentation-property' now evaluates the value of
2105 the given property to obtain a string if it doesn't refer to etc/DOC
2106 and isn't a string.
2107
2108 ** If called for a symbol, the function `documentation' now looks for
2109 a `function-documentation' property of that symbol. If it has a non-nil
2110 value, the documentation is taken from that value. If the value is
2111 not a string, it is evaluated to obtain a string.
2112
2113 +++
2114 ** The last argument of `define-key-after' defaults to t for convenience.
2115
2116 ** The new function `replace-regexp-in-string' replaces all matches
2117 for a regexp in a string.
2118
2119 ** `mouse-position' now runs the abnormal hook
2120 `mouse-position-function'.
2121
2122 ** The function string-to-number now returns a float for numbers
2123 that don't fit into a Lisp integer.
2124
2125 ** The variable keyword-symbols-constants-flag has been removed.
2126 Keywords are now always considered constants.
2127
2128 +++
2129 ** The new function `delete-and-extract-region' deletes text and
2130 returns it.
2131
2132 ** The function `clear-this-command-keys' now also clears the vector
2133 returned by function `recent-keys'.
2134
2135 +++
2136 ** Variables `beginning-of-defun-function' and `end-of-defun-function'
2137 can be used to define handlers for the functions that find defuns.
2138 Major modes can define these locally instead of rebinding M-C-a
2139 etc. if the normal conventions for defuns are not appropriate for the
2140 mode.
2141
2142 +++
2143 ** easy-mmode-define-minor-mode now takes an additional BODY argument
2144 and is renamed `define-minor-mode'.
2145
2146 +++
2147 ** If an abbrev has a hook function which is a symbol, and that symbol
2148 has a non-nil `no-self-insert' property, the return value of the hook
2149 function specifies whether an expansion has been done or not. If it
2150 returns nil, abbrev-expand also returns nil, meaning "no expansion has
2151 been performed."
2152
2153 When abbrev expansion is done by typing a self-inserting character,
2154 and the abbrev has a hook with the `no-self-insert' property, and the
2155 hook function returns non-nil meaning expansion has been done,
2156 then the self-inserting character is not inserted.
2157
2158 +++
2159 ** The function `intern-soft' now accepts a symbol as first argument.
2160 In this case, that exact symbol is looked up in the specified obarray,
2161 and the function's value is nil if it is not found.
2162
2163 +++
2164 ** The new macro `with-syntax-table' can be used to evaluate forms
2165 with the syntax table of the current buffer temporarily set to a
2166 specified table.
2167
2168 (with-syntax-table TABLE &rest BODY)
2169
2170 Evaluate BODY with syntax table of current buffer set to a copy of
2171 TABLE. The current syntax table is saved, BODY is evaluated, and the
2172 saved table is restored, even in case of an abnormal exit. Value is
2173 what BODY returns.
2174
2175 +++
2176 ** Regular expressions now support intervals \{n,m\} as well as
2177 Perl's shy-groups \(?:...\) and non-greedy *? +? and ?? operators.
2178
2179 +++
2180 ** The optional argument BUFFER of function file-local-copy has been
2181 removed since it wasn't used by anything.
2182
2183 +++
2184 ** The file name argument of function `file-locked-p' is now required
2185 instead of being optional.
2186
2187 +++
2188 ** The new built-in error `text-read-only' is signaled when trying to
2189 modify read-only text.
2190
2191 +++
2192 ** New functions and variables for locales.
2193
2194 The new variable `locale-coding-system' specifies how to encode and
2195 decode strings passed to low-level message functions like strerror and
2196 time functions like strftime. The new variables
2197 `system-messages-locale' and `system-time-locale' give the system
2198 locales to be used when invoking these two types of functions.
2199
2200 The new function `set-locale-environment' sets the language
2201 environment, preferred coding system, and locale coding system from
2202 the system locale as specified by the LC_ALL, LC_CTYPE, and LANG
2203 environment variables. Normally, it is invoked during startup and need
2204 not be invoked thereafter. It uses the new variables
2205 `locale-language-names', `locale-charset-language-names', and
2206 `locale-preferred-coding-systems' to make its decisions.
2207
2208 +++
2209 ** syntax tables now understand nested comments.
2210 To declare a comment syntax as allowing nesting, just add an `n'
2211 modifier to either of the characters of the comment end and the comment
2212 start sequences.
2213
2214 +++
2215 ** The function `pixmap-spec-p' has been renamed `bitmap-spec-p'
2216 because `bitmap' is more in line with the usual X terminology.
2217
2218 +++
2219 ** New function `propertize'
2220
2221 The new function `propertize' can be used to conveniently construct
2222 strings with text properties.
2223
2224 - Function: propertize STRING &rest PROPERTIES
2225
2226 Value is a copy of STRING with text properties assigned as specified
2227 by PROPERTIES. PROPERTIES is a sequence of pairs PROPERTY VALUE, with
2228 PROPERTY being the name of a text property and VALUE being the
2229 specified value of that property. Example:
2230
2231 (propertize "foo" 'face 'bold 'read-only t)
2232
2233 +++
2234 ** push and pop macros.
2235
2236 Simple versions of the push and pop macros of Common Lisp
2237 are now defined in Emacs Lisp. These macros allow only symbols
2238 as the place that holds the list to be changed.
2239
2240 (push NEWELT LISTNAME) add NEWELT to the front of LISTNAME's value.
2241 (pop LISTNAME) return first elt of LISTNAME, and remove it
2242 (thus altering the value of LISTNAME).
2243
2244 ** New dolist and dotimes macros.
2245
2246 Simple versions of the dolist and dotimes macros of Common Lisp
2247 are now defined in Emacs Lisp.
2248
2249 (dolist (VAR LIST [RESULT]) BODY...)
2250 Execute body once for each element of LIST,
2251 using the variable VAR to hold the current element.
2252 Then return the value of RESULT, or nil if RESULT is omitted.
2253
2254 (dotimes (VAR COUNT [RESULT]) BODY...)
2255 Execute BODY with VAR bound to successive integers running from 0,
2256 inclusive, to COUNT, exclusive.
2257 Then return the value of RESULT, or nil if RESULT is omitted.
2258
2259 +++
2260 ** Regular expressions now support Posix character classes such
2261 as [:alpha:], [:space:] and so on.
2262
2263 [:digit:] matches 0 through 9
2264 [:cntrl:] matches ASCII control characters
2265 [:xdigit:] matches 0 through 9, a through f and A through F.
2266 [:blank:] matches space and tab only
2267 [:graph:] matches graphic characters--everything except ASCII control chars,
2268 space, and DEL.
2269 [:print:] matches printing characters--everything except ASCII control chars
2270 and DEL.
2271 [:alnum:] matches letters and digits.
2272 (But at present, for multibyte characters,
2273 it matches anything that has word syntax.)
2274 [:alpha:] matches letters.
2275 (But at present, for multibyte characters,
2276 it matches anything that has word syntax.)
2277 [:ascii:] matches ASCII (unibyte) characters.
2278 [:nonascii:] matches non-ASCII (multibyte) characters.
2279 [:lower:] matches anything lower-case.
2280 [:punct:] matches punctuation.
2281 (But at present, for multibyte characters,
2282 it matches anything that has non-word syntax.)
2283 [:space:] matches anything that has whitespace syntax.
2284 [:upper:] matches anything upper-case.
2285 [:word:] matches anything that has word syntax.
2286
2287 +++
2288 ** Emacs now has built-in hash tables.
2289
2290 The following functions are defined for hash tables:
2291
2292 - Function: make-hash-table ARGS
2293
2294 The argument list ARGS consists of keyword/argument pairs. All arguments
2295 are optional. The following arguments are defined:
2296
2297 :test TEST
2298
2299 TEST must be a symbol specifying how to compare keys. Default is `eql'.
2300 Predefined are `eq', `eql' and `equal'. If TEST is not predefined,
2301 it must have been defined with `define-hash-table-test'.
2302
2303 :size SIZE
2304
2305 SIZE must be an integer > 0 giving a hint to the implementation how
2306 many elements will be put in the hash table. Default size is 65.
2307
2308 :rehash-size REHASH-SIZE
2309
2310 REHASH-SIZE specifies by how much to grow a hash table once it becomes
2311 full. If REHASH-SIZE is an integer, add that to the hash table's old
2312 size to get the new size. Otherwise, REHASH-SIZE must be a float >
2313 1.0, and the new size is computed by multiplying REHASH-SIZE with the
2314 old size. Default rehash size is 1.5.
2315
2316 :rehash-threshold THRESHOLD
2317
2318 THRESHOLD must be a float > 0 and <= 1.0 specifying when to resize the
2319 hash table. It is resized when the ratio of (number of entries) /
2320 (size of hash table) is >= THRESHOLD. Default threshold is 0.8.
2321
2322 :weakness WEAK
2323
2324 WEAK must be either nil, one of the symbols `key, `value',
2325 `key-or-value', `key-and-value', or t, meaning the same as
2326 `key-and-value'. Entries are removed from weak tables during garbage
2327 collection if their key and/or value are not referenced elsewhere
2328 outside of the hash table. Default are non-weak hash tables.
2329
2330 - Function: makehash &optional TEST
2331
2332 Similar to make-hash-table, but only TEST can be specified.
2333
2334 - Function: hash-table-p TABLE
2335
2336 Returns non-nil if TABLE is a hash table object.
2337
2338 - Function: copy-hash-table TABLE
2339
2340 Returns a copy of TABLE. Only the table itself is copied, keys and
2341 values are shared.
2342
2343 - Function: hash-table-count TABLE
2344
2345 Returns the number of entries in TABLE.
2346
2347 - Function: hash-table-rehash-size TABLE
2348
2349 Returns the rehash size of TABLE.
2350
2351 - Function: hash-table-rehash-threshold TABLE
2352
2353 Returns the rehash threshold of TABLE.
2354
2355 - Function: hash-table-rehash-size TABLE
2356
2357 Returns the size of TABLE.
2358
2359 - Function: hash-table-test TABLE
2360
2361 Returns the test TABLE uses to compare keys.
2362
2363 - Function: hash-table-weakness TABLE
2364
2365 Returns the weakness specified for TABLE.
2366
2367 - Function: clrhash TABLE
2368
2369 Clear TABLE.
2370
2371 - Function: gethash KEY TABLE &optional DEFAULT
2372
2373 Look up KEY in TABLE and return its associated VALUE or DEFAULT if
2374 not found.
2375
2376 - Function: puthash KEY VALUE TABLE
2377
2378 Associate KEY with VALUE in TABLE. If KEY is already associated with
2379 another value, replace the old value with VALUE.
2380
2381 - Function: remhash KEY TABLE
2382
2383 Remove KEY from TABLE if it is there.
2384
2385 - Function: maphash FUNCTION TABLE
2386
2387 Call FUNCTION for all elements in TABLE. FUNCTION must take two
2388 arguments KEY and VALUE.
2389
2390 - Function: sxhash OBJ
2391
2392 Return a hash code for Lisp object OBJ.
2393
2394 - Function: define-hash-table-test NAME TEST-FN HASH-FN
2395
2396 Define a new hash table test named NAME. If NAME is specified as
2397 a test in `make-hash-table', the table created will use TEST-FN for
2398 comparing keys, and HASH-FN to compute hash codes for keys. Test
2399 and hash function are stored as symbol property `hash-table-test'
2400 of NAME with a value of (TEST-FN HASH-FN).
2401
2402 TEST-FN must take two arguments and return non-nil if they are the same.
2403
2404 HASH-FN must take one argument and return an integer that is the hash
2405 code of the argument. The function should use the whole range of
2406 integer values for hash code computation, including negative integers.
2407
2408 Example: The following creates a hash table whose keys are supposed to
2409 be strings that are compared case-insensitively.
2410
2411 (defun case-fold-string= (a b)
2412 (compare-strings a nil nil b nil nil t))
2413
2414 (defun case-fold-string-hash (a)
2415 (sxhash (upcase a)))
2416
2417 (define-hash-table-test 'case-fold 'case-fold-string=
2418 'case-fold-string-hash))
2419
2420 (make-hash-table :test 'case-fold)
2421
2422 +++
2423 ** The Lisp reader handles circular structure.
2424
2425 It now works to use the #N= and #N# constructs to represent
2426 circular structures. For example, #1=(a . #1#) represents
2427 a cons cell which is its own cdr.
2428
2429 +++
2430 ** The Lisp printer handles circular structure.
2431
2432 If you bind print-circle to a non-nil value, the Lisp printer outputs
2433 #N= and #N# constructs to represent circular and shared structure.
2434
2435 +++
2436 ** If the second argument to `move-to-column' is anything but nil or
2437 t, that means replace a tab with spaces if necessary to reach the
2438 specified column, but do not add spaces at the end of the line if it
2439 is too short to reach that column.
2440
2441 +++
2442 ** perform-replace has a new feature: the REPLACEMENTS argument may
2443 now be a cons cell (FUNCTION . DATA). This means to call FUNCTION
2444 after each match to get the replacement text. FUNCTION is called with
2445 two arguments: DATA, and the number of replacements already made.
2446
2447 If the FROM-STRING contains any upper-case letters,
2448 perform-replace also turns off `case-fold-search' temporarily
2449 and inserts the replacement text without altering case in it.
2450
2451 +++
2452 ** The function buffer-size now accepts an optional argument
2453 to specify which buffer to return the size of.
2454
2455 +++
2456 ** The calendar motion commands now run the normal hook
2457 calendar-move-hook after moving point.
2458
2459 +++
2460 ** The new variable small-temporary-file-directory specifies a
2461 directory to use for creating temporary files that are likely to be
2462 small. (Certain Emacs features use this directory.) If
2463 small-temporary-file-directory is nil, they use
2464 temporary-file-directory instead.
2465
2466 +++
2467 ** The variable `inhibit-modification-hooks', if non-nil, inhibits all
2468 the hooks that track changes in the buffer. This affects
2469 `before-change-functions' and `after-change-functions', as well as
2470 hooks attached to text properties and overlay properties.
2471
2472 +++
2473 ** assoc-delete-all is a new function that deletes all the
2474 elements of an alist which have a particular value as the car.
2475
2476 +++
2477 ** make-temp-file provides a more reliable way to create a temporary file.
2478
2479 make-temp-file is used like make-temp-name, except that it actually
2480 creates the file before it returns. This prevents a timing error,
2481 ensuring that no other job can use the same name for a temporary file.
2482
2483 +++
2484 ** New exclusive-open feature in `write-region'
2485
2486 The optional seventh arg is now called MUSTBENEW. If non-nil, it insists
2487 on a check for an existing file with the same name. If MUSTBENEW
2488 is `excl', that means to get an error if the file already exists;
2489 never overwrite. If MUSTBENEW is neither nil nor `excl', that means
2490 ask for confirmation before overwriting, but do go ahead and
2491 overwrite the file if the user gives confirmation.
2492
2493 If the MUSTBENEW argument in `write-region' is `excl',
2494 that means to use a special feature in the `open' system call
2495 to get an error if the file exists at that time.
2496 The error reported is `file-already-exists'.
2497
2498 +++
2499 ** Function `format' now handles text properties.
2500
2501 Text properties of the format string are applied to the result string.
2502 If the result string is longer than the format string, text properties
2503 ending at the end of the format string are extended to the end of the
2504 result string.
2505
2506 Text properties from string arguments are applied to the result
2507 string where arguments appear in the result string.
2508
2509 Example:
2510
2511 (let ((s1 "hello, %s")
2512 (s2 "world"))
2513 (put-text-property 0 (length s1) 'face 'bold s1)
2514 (put-text-property 0 (length s2) 'face 'italic s2)
2515 (format s1 s2))
2516
2517 results in a bold-face string with an italic `world' at the end.
2518
2519 +++
2520 ** Messages can now be displayed with text properties.
2521
2522 Text properties are handled as described above for function `format'.
2523 The following example displays a bold-face message with an italic
2524 argument in it.
2525
2526 (let ((msg "hello, %s!")
2527 (arg "world"))
2528 (put-text-property 0 (length msg) 'face 'bold msg)
2529 (put-text-property 0 (length arg) 'face 'italic arg)
2530 (message msg arg))
2531
2532 +++
2533 ** Sound support
2534
2535 Emacs supports playing sound files on GNU/Linux and the free BSDs
2536 (Voxware driver and native BSD driver, aka as Luigi's driver).
2537
2538 Currently supported file formats are RIFF-WAVE (*.wav) and Sun Audio
2539 (*.au). You must configure Emacs with the option `--with-sound=yes'
2540 to enable sound support.
2541
2542 Sound files can be played by calling (play-sound SOUND). SOUND is a
2543 list of the form `(sound PROPERTY...)'. The function is only defined
2544 when sound support is present for the system on which Emacs runs. The
2545 functions runs `play-sound-functions' with one argument which is the
2546 sound to play, before playing the sound.
2547
2548 The following sound properties are supported:
2549
2550 - `:file FILE'
2551
2552 FILE is a file name. If FILE isn't an absolute name, it will be
2553 searched relative to `data-directory'.
2554
2555 - `:data DATA'
2556
2557 DATA is a string containing sound data. Either :file or :data
2558 may be present, but not both.
2559
2560 - `:volume VOLUME'
2561
2562 VOLUME must be an integer in the range 0..100 or a float in the range
2563 0..1. This property is optional.
2564
2565 Other properties are ignored.
2566
2567 ** `multimedia' is a new Finder keyword and Custom group.
2568
2569 ** keywordp is a new predicate to test efficiently for an object being
2570 a keyword symbol.
2571
2572 ** Changes to garbage collection
2573
2574 *** The function garbage-collect now additionally returns the number
2575 of live and free strings.
2576
2577 *** There is a new variable `strings-consed' holding the number of
2578 strings that have been consed so far.
2579
2580 \f
2581 * Lisp-level Display features added after release 2.6 of the Emacs
2582 Lisp Manual
2583
2584 *** On window systems, `glyph-table' is no longer used.
2585
2586 +++
2587 ** Help strings in menu items are now used to provide `help-echo' text.
2588
2589 ** The function `image-size' can be used to determine the size of an
2590 image.
2591
2592 - Function: image-size SPEC &optional PIXELS FRAME
2593
2594 Return the size of an image as a pair (WIDTH . HEIGHT).
2595
2596 SPEC is an image specification. PIXELS non-nil means return sizes
2597 measured in pixels, otherwise return sizes measured in canonical
2598 character units (fractions of the width/height of the frame's default
2599 font). FRAME is the frame on which the image will be displayed.
2600 FRAME nil or omitted means use the selected frame.
2601
2602 ** The function `image-mask-p' can be used to determine if an image
2603 has a mask bitmap.
2604
2605 - Function: image-mask-p SPEC &optional FRAME
2606
2607 Return t if image SPEC has a mask bitmap.
2608 FRAME is the frame on which the image will be displayed. FRAME nil
2609 or omitted means use the selected frame.
2610
2611 +++
2612 ** The function `find-image' can be used to find a usable image
2613 satisfying one of a list of specifications.
2614
2615 +++
2616 ** The STRING argument of `put-image' and `insert-image' is now
2617 optional.
2618
2619 +++
2620 ** Image specifications may contain the property `:ascent center' (see
2621 below).
2622
2623 \f
2624 * New Lisp-level Display features in Emacs 21.1
2625
2626 Note that +++ before an item means the Lisp manual has been updated.
2627 --- means that I have decided it does not need to be in the Lisp manual.
2628 When you add a new item, please add it without either +++ or ---
2629 so I will know I still need to look at it -- rms.
2630
2631 ** The function tty-suppress-bold-inverse-default-colors can be used
2632 to make Emacs avoid displaying text with bold black foreground on TTYs.
2633
2634 Some terminals, notably PC consoles, emulate bold text by displaying
2635 text in brighter colors. On such a console, a bold black foreground
2636 is displayed in a gray color. If this turns out to be hard to read on
2637 your monitor---the problem occurred with the mode line on
2638 laptops---you can instruct Emacs to ignore the text's boldness, and to
2639 just display it black instead.
2640
2641 This situation can't be detected automatically. You will have to put
2642 a line like
2643
2644 (tty-suppress-bold-inverse-default-colors t)
2645
2646 in your `.emacs'.
2647
2648 ** New face implementation.
2649
2650 Emacs faces have been reimplemented from scratch. They don't use XLFD
2651 font names anymore and face merging now works as expected.
2652
2653 +++
2654 *** New faces.
2655
2656 Each face can specify the following display attributes:
2657
2658 1. Font family or fontset alias name.
2659
2660 2. Relative proportionate width, aka character set width or set
2661 width (swidth), e.g. `semi-compressed'.
2662
2663 3. Font height in 1/10pt
2664
2665 4. Font weight, e.g. `bold'.
2666
2667 5. Font slant, e.g. `italic'.
2668
2669 6. Foreground color.
2670
2671 7. Background color.
2672
2673 8. Whether or not characters should be underlined, and in what color.
2674
2675 9. Whether or not characters should be displayed in inverse video.
2676
2677 10. A background stipple, a bitmap.
2678
2679 11. Whether or not characters should be overlined, and in what color.
2680
2681 12. Whether or not characters should be strike-through, and in what
2682 color.
2683
2684 13. Whether or not a box should be drawn around characters, its
2685 color, the width of the box lines, and 3D appearance.
2686
2687 Faces are frame-local by nature because Emacs allows to define the
2688 same named face (face names are symbols) differently for different
2689 frames. Each frame has an alist of face definitions for all named
2690 faces. The value of a named face in such an alist is a Lisp vector
2691 with the symbol `face' in slot 0, and a slot for each each of the face
2692 attributes mentioned above.
2693
2694 There is also a global face alist `face-new-frame-defaults'. Face
2695 definitions from this list are used to initialize faces of newly
2696 created frames.
2697
2698 A face doesn't have to specify all attributes. Those not specified
2699 have a nil value. Faces specifying all attributes are called
2700 `fully-specified'.
2701
2702 +++
2703 *** Face merging.
2704
2705 The display style of a given character in the text is determined by
2706 combining several faces. This process is called `face merging'. Any
2707 aspect of the display style that isn't specified by overlays or text
2708 properties is taken from the `default' face. Since it is made sure
2709 that the default face is always fully-specified, face merging always
2710 results in a fully-specified face.
2711
2712 +++
2713 *** Face realization.
2714
2715 After all face attributes for a character have been determined by
2716 merging faces of that character, that face is `realized'. The
2717 realization process maps face attributes to what is physically
2718 available on the system where Emacs runs. The result is a `realized
2719 face' in form of an internal structure which is stored in the face
2720 cache of the frame on which it was realized.
2721
2722 Face realization is done in the context of the charset of the
2723 character to display because different fonts and encodings are used
2724 for different charsets. In other words, for characters of different
2725 charsets, different realized faces are needed to display them.
2726
2727 Except for composite characters, faces are always realized for a
2728 specific character set and contain a specific font, even if the face
2729 being realized specifies a fontset. The reason is that the result of
2730 the new font selection stage is better than what can be done with
2731 statically defined font name patterns in fontsets.
2732
2733 In unibyte text, Emacs' charsets aren't applicable; function
2734 `char-charset' reports ASCII for all characters, including those >
2735 0x7f. The X registry and encoding of fonts to use is determined from
2736 the variable `face-default-registry' in this case. The variable is
2737 initialized at Emacs startup time from the font the user specified for
2738 Emacs.
2739
2740 Currently all unibyte text, i.e. all buffers with
2741 `enable-multibyte-characters' nil are displayed with fonts of the same
2742 registry and encoding `face-default-registry'. This is consistent
2743 with the fact that languages can also be set globally, only.
2744
2745 ++++
2746 **** Clearing face caches.
2747
2748 The Lisp function `clear-face-cache' can be called to clear face caches
2749 on all frames. If called with a non-nil argument, it will also unload
2750 unused fonts.
2751
2752 +++
2753 *** Font selection.
2754
2755 Font selection tries to find the best available matching font for a
2756 given (charset, face) combination. This is done slightly differently
2757 for faces specifying a fontset, or a font family name.
2758
2759 If the face specifies a fontset name, that fontset determines a
2760 pattern for fonts of the given charset. If the face specifies a font
2761 family, a font pattern is constructed. Charset symbols have a
2762 property `x-charset-registry' for that purpose that maps a charset to
2763 an XLFD registry and encoding in the font pattern constructed.
2764
2765 Available fonts on the system on which Emacs runs are then matched
2766 against the font pattern. The result of font selection is the best
2767 match for the given face attributes in this font list.
2768
2769 Font selection can be influenced by the user.
2770
2771 The user can specify the relative importance he gives the face
2772 attributes width, height, weight, and slant by setting
2773 face-font-selection-order (faces.el) to a list of face attribute
2774 names. The default is (:width :height :weight :slant), and means
2775 that font selection first tries to find a good match for the font
2776 width specified by a face, then---within fonts with that width---tries
2777 to find a best match for the specified font height, etc.
2778
2779 Setting `face-alternative-font-family-alist' allows the user to
2780 specify alternative font families to try if a family specified by a
2781 face doesn't exist.
2782
2783 +++
2784 **** Scalable fonts
2785
2786 Emacs can make use of scalable fonts but doesn't do so by default,
2787 since the use of too many or too big scalable fonts may crash XFree86
2788 servers.
2789
2790 To enable scalable font use, set the variable
2791 `scalable-fonts-allowed'. A value of nil, the default, means never use
2792 scalable fonts. A value of t means any scalable font may be used.
2793 Otherwise, the value must be a list of regular expressions. A
2794 scalable font may then be used if it matches a regular expression from
2795 that list. Example:
2796
2797 (setq scalable-fonts-allowed '("muleindian-2$"))
2798
2799 allows the use of scalable fonts with registry `muleindian-2'.
2800
2801 +++
2802 *** Functions and variables related to font selection.
2803
2804 - Function: x-family-fonts &optional FAMILY FRAME
2805
2806 Return a list of available fonts of family FAMILY on FRAME. If FAMILY
2807 is omitted or nil, list all families. Otherwise, FAMILY must be a
2808 string, possibly containing wildcards `?' and `*'.
2809
2810 If FRAME is omitted or nil, use the selected frame. Each element of
2811 the result is a vector [FAMILY WIDTH POINT-SIZE WEIGHT SLANT FIXED-P
2812 FULL REGISTRY-AND-ENCODING]. FAMILY is the font family name.
2813 POINT-SIZE is the size of the font in 1/10 pt. WIDTH, WEIGHT, and
2814 SLANT are symbols describing the width, weight and slant of the font.
2815 These symbols are the same as for face attributes. FIXED-P is non-nil
2816 if the font is fixed-pitch. FULL is the full name of the font, and
2817 REGISTRY-AND-ENCODING is a string giving the registry and encoding of
2818 the font. The result list is sorted according to the current setting
2819 of the face font sort order.
2820
2821 - Function: x-font-family-list
2822
2823 Return a list of available font families on FRAME. If FRAME is
2824 omitted or nil, use the selected frame. Value is a list of conses
2825 (FAMILY . FIXED-P) where FAMILY is a font family, and FIXED-P is
2826 non-nil if fonts of that family are fixed-pitch.
2827
2828 - Variable: font-list-limit
2829
2830 Limit for font matching. If an integer > 0, font matching functions
2831 won't load more than that number of fonts when searching for a
2832 matching font. The default is currently 100.
2833
2834 +++
2835 *** Setting face attributes.
2836
2837 For the most part, the new face implementation is interface-compatible
2838 with the old one. Old face attribute related functions are now
2839 implemented in terms of the new functions `set-face-attribute' and
2840 `face-attribute'.
2841
2842 Face attributes are identified by their names which are keyword
2843 symbols. All attributes can be set to `unspecified'.
2844
2845 The following attributes are recognized:
2846
2847 `:family'
2848
2849 VALUE must be a string specifying the font family, e.g. ``courier'',
2850 or a fontset alias name. If a font family is specified, wild-cards `*'
2851 and `?' are allowed.
2852
2853 `:width'
2854
2855 VALUE specifies the relative proportionate width of the font to use.
2856 It must be one of the symbols `ultra-condensed', `extra-condensed',
2857 `condensed', `semi-condensed', `normal', `semi-expanded', `expanded',
2858 `extra-expanded', or `ultra-expanded'.
2859
2860 `:height'
2861
2862 VALUE must be either an integer specifying the height of the font to use
2863 in 1/10 pt, a floating point number specifying the amount by which to
2864 scale any underlying face, or a function, which is called with the old
2865 height (from the underlying face), and should return the new height.
2866
2867 `:weight'
2868
2869 VALUE specifies the weight of the font to use. It must be one of the
2870 symbols `ultra-bold', `extra-bold', `bold', `semi-bold', `normal',
2871 `semi-light', `light', `extra-light', `ultra-light'.
2872
2873 `:slant'
2874
2875 VALUE specifies the slant of the font to use. It must be one of the
2876 symbols `italic', `oblique', `normal', `reverse-italic', or
2877 `reverse-oblique'.
2878
2879 `:foreground', `:background'
2880
2881 VALUE must be a color name, a string.
2882
2883 `:underline'
2884
2885 VALUE specifies whether characters in FACE should be underlined. If
2886 VALUE is t, underline with foreground color of the face. If VALUE is
2887 a string, underline with that color. If VALUE is nil, explicitly
2888 don't underline.
2889
2890 `:overline'
2891
2892 VALUE specifies whether characters in FACE should be overlined. If
2893 VALUE is t, overline with foreground color of the face. If VALUE is a
2894 string, overline with that color. If VALUE is nil, explicitly don't
2895 overline.
2896
2897 `:strike-through'
2898
2899 VALUE specifies whether characters in FACE should be drawn with a line
2900 striking through them. If VALUE is t, use the foreground color of the
2901 face. If VALUE is a string, strike-through with that color. If VALUE
2902 is nil, explicitly don't strike through.
2903
2904 `:box'
2905
2906 VALUE specifies whether characters in FACE should have a box drawn
2907 around them. If VALUE is nil, explicitly don't draw boxes. If
2908 VALUE is t, draw a box with lines of width 1 in the foreground color
2909 of the face. If VALUE is a string, the string must be a color name,
2910 and the box is drawn in that color with a line width of 1. Otherwise,
2911 VALUE must be a property list of the form `(:line-width WIDTH
2912 :color COLOR :style STYLE)'. If a keyword/value pair is missing from
2913 the property list, a default value will be used for the value, as
2914 specified below. WIDTH specifies the width of the lines to draw; it
2915 defaults to 1. COLOR is the name of the color to draw in, default is
2916 the foreground color of the face for simple boxes, and the background
2917 color of the face for 3D boxes. STYLE specifies whether a 3D box
2918 should be draw. If STYLE is `released-button', draw a box looking
2919 like a released 3D button. If STYLE is `pressed-button' draw a box
2920 that appears like a pressed button. If STYLE is nil, the default if
2921 the property list doesn't contain a style specification, draw a 2D
2922 box.
2923
2924 `:inverse-video'
2925
2926 VALUE specifies whether characters in FACE should be displayed in
2927 inverse video. VALUE must be one of t or nil.
2928
2929 `:stipple'
2930
2931 If VALUE is a string, it must be the name of a file of pixmap data.
2932 The directories listed in the `x-bitmap-file-path' variable are
2933 searched. Alternatively, VALUE may be a list of the form (WIDTH
2934 HEIGHT DATA) where WIDTH and HEIGHT are the size in pixels, and DATA
2935 is a string containing the raw bits of the bitmap. VALUE nil means
2936 explicitly don't use a stipple pattern.
2937
2938 For convenience, attributes `:family', `:width', `:height', `:weight',
2939 and `:slant' may also be set in one step from an X font name:
2940
2941 `:font'
2942
2943 Set font-related face attributes from VALUE. VALUE must be a valid
2944 XLFD font name. If it is a font name pattern, the first matching font
2945 is used--this is for compatibility with the behavior of previous
2946 versions of Emacs.
2947
2948 For compatibility with Emacs 20, keywords `:bold' and `:italic' can
2949 be used to specify that a bold or italic font should be used. VALUE
2950 must be t or nil in that case. A value of `unspecified' is not allowed."
2951
2952 Please see also the documentation of `set-face-attribute' and
2953 `defface'.
2954
2955 `:inherit'
2956
2957 VALUE is the name of a face from which to inherit attributes, or a list
2958 of face names. Attributes from inherited faces are merged into the face
2959 like an underlying face would be, with higher priority than underlying faces.
2960
2961 *** Face attributes and X resources
2962
2963 The following X resource names can be used to set face attributes
2964 from X resources:
2965
2966 Face attribute X resource class
2967 -----------------------------------------------------------------------
2968 :family attributeFamily . Face.AttributeFamily
2969 :width attributeWidth Face.AttributeWidth
2970 :height attributeHeight Face.AttributeHeight
2971 :weight attributeWeight Face.AttributeWeight
2972 :slant attributeSlant Face.AttributeSlant
2973 foreground attributeForeground Face.AttributeForeground
2974 :background attributeBackground . Face.AttributeBackground
2975 :overline attributeOverline Face.AttributeOverline
2976 :strike-through attributeStrikeThrough Face.AttributeStrikeThrough
2977 :box attributeBox Face.AttributeBox
2978 :underline attributeUnderline Face.AttributeUnderline
2979 :inverse-video attributeInverse Face.AttributeInverse
2980 :stipple attributeStipple Face.AttributeStipple
2981 or attributeBackgroundPixmap
2982 Face.AttributeBackgroundPixmap
2983 :font attributeFont Face.AttributeFont
2984 :bold attributeBold Face.AttributeBold
2985 :italic attributeItalic . Face.AttributeItalic
2986 :font attributeFont Face.AttributeFont
2987
2988 +++
2989 *** Text property `face'.
2990
2991 The value of the `face' text property can now be a single face
2992 specification or a list of such specifications. Each face
2993 specification can be
2994
2995 1. A symbol or string naming a Lisp face.
2996
2997 2. A property list of the form (KEYWORD VALUE ...) where each
2998 KEYWORD is a face attribute name, and VALUE is an appropriate value
2999 for that attribute. Please see the doc string of `set-face-attribute'
3000 for face attribute names.
3001
3002 3. Conses of the form (FOREGROUND-COLOR . COLOR) or
3003 (BACKGROUND-COLOR . COLOR) where COLOR is a color name. This is
3004 for compatibility with previous Emacs versions.
3005
3006 +++
3007 ** Support functions for colors on text-only terminals.
3008
3009 The function `tty-color-define' can be used to define colors for use
3010 on TTY and MSDOS frames. It maps a color name to a color number on
3011 the terminal. Emacs defines a couple of common color mappings by
3012 default. You can get defined colors with a call to
3013 `defined-colors'. The function `tty-color-clear' can be
3014 used to clear the mapping table.
3015
3016 ** Unified support for colors independent of frame type.
3017
3018 The new functions `defined-colors', `color-defined-p', `color-values',
3019 and `display-color-p' work for any type of frame. On frames whose
3020 type is neither x nor w32, these functions transparently map X-style
3021 color specifications to the closest colors supported by the frame
3022 display. Lisp programs should use these new functions instead of the
3023 old `x-defined-colors', `x-color-defined-p', `x-color-values', and
3024 `x-display-color-p'. (The old function names are still available for
3025 compatibility; they are now aliases of the new names.) Lisp programs
3026 should no more look at the value of the variable window-system to
3027 modify their color-related behavior.
3028
3029 The primitives `color-gray-p' and `color-supported-p' also work for
3030 any frame type.
3031
3032 ** Platform-independent functions to describe display capabilities.
3033
3034 The new functions `display-mouse-p', `display-popup-menus-p',
3035 `display-graphic-p', `display-selections-p', `display-screens',
3036 `display-pixel-width', `display-pixel-height', `display-mm-width',
3037 `display-mm-height', `display-backing-store', `display-save-under',
3038 `display-planes', `display-color-cells', `display-visual-class', and
3039 `display-grayscale-p' describe the basic capabilities of a particular
3040 display. Lisp programs should call these functions instead of testing
3041 the value of the variables `window-system' or `system-type', or calling
3042 platform-specific functions such as `x-display-pixel-width'.
3043
3044 +++
3045 ** The minibuffer prompt is now actually inserted in the minibuffer.
3046
3047 This makes it possible to scroll through the prompt, if you want to.
3048
3049 The function minubuffer-prompt-end returns the current position of the
3050 end of the minibuffer prompt, if the minibuffer is current.
3051 Otherwise, it returns zero.
3052
3053 ** New `field' abstraction in buffers.
3054
3055 There is now code to support an abstraction called `fields' in emacs
3056 buffers. A field is a contiguous region of text with the same `field'
3057 property (which can be a text property or an overlay).
3058
3059 Many emacs functions, such as forward-word, forward-sentence,
3060 forward-paragraph, beginning-of-line, etc., stop moving when they come
3061 to the boundary between fields; beginning-of-line and end-of-line will
3062 not let the point move past the field boundary, but other movement
3063 commands continue into the next field if repeated. Stopping at field
3064 boundaries can be suppressed programmatically by binding
3065 `inhibit-field-text-motion' to a non-nil value around calls to these
3066 functions.
3067
3068 Now that the minibuffer prompt is inserted into the minibuffer, it is in
3069 a separate field from the user-input part of the buffer, so that common
3070 editing commands treat the user's text separately from the prompt.
3071
3072 The following functions are defined for operating on fields:
3073
3074 - Function: constrain-to-field NEW-POS OLD-POS &optional ESCAPE-FROM-EDGE ONLY-IN-LINE INHIBIT-CAPTURE-PROPERTY
3075
3076 Return the position closest to NEW-POS that is in the same field as OLD-POS.
3077
3078 A field is a region of text with the same `field' property.
3079 If NEW-POS is nil, then the current point is used instead, and set to the
3080 constrained position if that is is different.
3081
3082 If OLD-POS is at the boundary of two fields, then the allowable
3083 positions for NEW-POS depends on the value of the optional argument
3084 ESCAPE-FROM-EDGE: If ESCAPE-FROM-EDGE is nil, then NEW-POS is
3085 constrained to the field that has the same `field' char-property
3086 as any new characters inserted at OLD-POS, whereas if ESCAPE-FROM-EDGE
3087 is non-nil, NEW-POS is constrained to the union of the two adjacent
3088 fields. Additionally, if two fields are separated by another field with
3089 the special value `boundary', then any point within this special field is
3090 also considered to be `on the boundary'.
3091
3092 If the optional argument ONLY-IN-LINE is non-nil and constraining
3093 NEW-POS would move it to a different line, NEW-POS is returned
3094 unconstrained. This useful for commands that move by line, like
3095 C-n or C-a, which should generally respect field boundaries
3096 only in the case where they can still move to the right line.
3097
3098 If the optional argument INHIBIT-CAPTURE-PROPERTY is non-nil, and OLD-POS has
3099 a non-nil property of that name, then any field boundaries are ignored.
3100
3101 Field boundaries are not noticed if `inhibit-field-text-motion' is non-nil.
3102
3103 - Function: delete-field &optional POS
3104
3105 Delete the field surrounding POS.
3106 A field is a region of text with the same `field' property.
3107 If POS is nil, the value of point is used for POS.
3108
3109 - Function: field-beginning &optional POS ESCAPE-FROM-EDGE
3110
3111 Return the beginning of the field surrounding POS.
3112 A field is a region of text with the same `field' property.
3113 If POS is nil, the value of point is used for POS.
3114 If ESCAPE-FROM-EDGE is non-nil and POS is at the beginning of its
3115 field, then the beginning of the *previous* field is returned.
3116
3117 - Function: field-end &optional POS ESCAPE-FROM-EDGE
3118
3119 Return the end of the field surrounding POS.
3120 A field is a region of text with the same `field' property.
3121 If POS is nil, the value of point is used for POS.
3122 If ESCAPE-FROM-EDGE is non-nil and POS is at the end of its field,
3123 then the end of the *following* field is returned.
3124
3125 - Function: field-string &optional POS
3126
3127 Return the contents of the field surrounding POS as a string.
3128 A field is a region of text with the same `field' property.
3129 If POS is nil, the value of point is used for POS.
3130
3131 - Function: field-string-no-properties &optional POS
3132
3133 Return the contents of the field around POS, without text-properties.
3134 A field is a region of text with the same `field' property.
3135 If POS is nil, the value of point is used for POS.
3136
3137 +++
3138 ** Image support.
3139
3140 Emacs can now display images. Images are inserted into text by giving
3141 strings or buffer text a `display' text property containing one of
3142 (AREA IMAGE) or IMAGE. The display of the `display' property value
3143 replaces the display of the characters having that property.
3144
3145 If the property value has the form (AREA IMAGE), AREA must be one of
3146 `(margin left-margin)', `(margin right-margin)' or `(margin nil)'. If
3147 AREA is `(margin nil)', IMAGE will be displayed in the text area of a
3148 window, otherwise it will be displayed in the left or right marginal
3149 area.
3150
3151 IMAGE is an image specification.
3152
3153 *** Image specifications
3154
3155 Image specifications are lists of the form `(image PROPS)' where PROPS
3156 is a property list whose keys are keyword symbols. Each
3157 specifications must contain a property `:type TYPE' with TYPE being a
3158 symbol specifying the image type, e.g. `xbm'. Properties not
3159 described below are ignored.
3160
3161 The following is a list of properties all image types share.
3162
3163 `:ascent ASCENT'
3164
3165 ASCENT must be a number in the range 0..100, or the symbol `center'.
3166 If it is a number, it specifies the percentage of the image's height
3167 to use for its ascent.
3168
3169 If not specified, ASCENT defaults to the value 50 which means that the
3170 image will be centered with the base line of the row it appears in.
3171
3172 If ASCENT is `center' the image is vertically centered around a
3173 centerline which is the vertical center of text drawn at the position
3174 of the image, in the manner specified by the text properties and
3175 overlays that apply to the image.
3176
3177 `:margin MARGIN'
3178
3179 MARGIN must be a number >= 0 specifying how many pixels to put as
3180 margin around the image. Default is 0.
3181
3182 `:relief RELIEF'
3183
3184 RELIEF is analogous to the `:relief' attribute of faces. Puts a relief
3185 around an image.
3186
3187 `:algorithm ALGO'
3188
3189 Apply an image algorithm to the image before displaying it.
3190
3191 ALGO `laplace' or `emboss' means apply a Laplace or ``emboss''
3192 edge-detection algorithm to the image.
3193
3194 ALGO `(edge-detection :matrix MATRIX :color-adjust ADJUST)' means
3195 apply a general edge-detection algorithm. MATRIX must be either a
3196 nine-element list or a nine-element vector of numbers. A pixel at
3197 position x/y in the transformed image is computed from original pixels
3198 around that position. MATRIX specifies, for each pixel in the
3199 neighborhood of x/y, a factor with which that pixel will influence the
3200 transformed pixel; element 0 specifies the factor for the pixel at
3201 x-1/y-1, element 1 the factor for the pixel at x/y-1 etc. as shown
3202 below.
3203
3204 (x-1/y-1 x/y-1 x+1/y-1
3205 x-1/y x/y x+1/y
3206 x-1/y+1 x/y+1 x+1/y+1)
3207
3208 The resulting pixel is computed from the color intensity of the color
3209 resulting from summing up the RGB values of surrounding pixels,
3210 multiplied by the specified factors, and dividing that sum by the sum
3211 of the factors' absolute values.
3212
3213 Laplace edge-detection currently uses a matrix of
3214
3215 (1 0 0
3216 0 0 0
3217 9 9 -1)
3218
3219 Emboss edge-detection uses a matrix of
3220
3221 ( 2 -1 0
3222 -1 0 1
3223 0 1 -2)
3224
3225 ALGO `disabled' means transform the image so that it looks
3226 ``disabled''.
3227
3228 `:mask MASK'
3229
3230 If MASK is `heuristic' or `(heuristic BG)', build a clipping mask for
3231 the image, so that the background of a frame is visible behind the
3232 image. If BG is not specified, or if BG is t, determine the
3233 background color of the image by looking at the 4 corners of the
3234 image, assuming the most frequently occuring color from the corners is
3235 the background color of the image. Otherwise, BG must be a list `(RED
3236 GREEN BLUE)' specifying the color to assume for the background of the
3237 image.
3238
3239 If MASK is nil, remove a mask from the image, if it has one. Images
3240 in some formats include a mask which can be removed by specifying
3241 `:mask nil'.
3242
3243 `:file FILE'
3244
3245 Load image from FILE. If FILE is not absolute after expanding it,
3246 search for the image in `data-directory'. Some image types support
3247 building images from data. When this is done, no `:file' property
3248 may be present in the image specification.
3249
3250 `:data DATA'
3251
3252 Get image data from DATA. (As of this writing, this is not yet
3253 supported for image type `postscript'). Either :file or :data may be
3254 present in an image specification, but not both. All image types
3255 support strings as DATA, some types allow additional types of DATA.
3256
3257 *** Supported image types
3258
3259 **** XBM, image type `xbm'.
3260
3261 XBM images don't require an external library. Additional image
3262 properties supported are
3263
3264 `:foreground FG'
3265
3266 FG must be a string specifying the image foreground color. Default
3267 is the frame's foreground.
3268
3269 `:background FG'
3270
3271 BG must be a string specifying the image foreground color. Default is
3272 the frame's background color.
3273
3274 XBM images can be constructed from data instead of file. In this
3275 case, the image specification must contain the following properties
3276 instead of a `:file' property.
3277
3278 `:width WIDTH'
3279
3280 WIDTH specifies the width of the image in pixels.
3281
3282 `:height HEIGHT'
3283
3284 HEIGHT specifies the height of the image in pixels.
3285
3286 `:data DATA'
3287
3288 DATA must be either
3289
3290 1. a string large enough to hold the bitmap data, i.e. it must
3291 have a size >= (WIDTH + 7) / 8 * HEIGHT
3292
3293 2. a bool-vector of size >= WIDTH * HEIGHT
3294
3295 3. a vector of strings or bool-vectors, one for each line of the
3296 bitmap.
3297
3298 4. a string that's an in-memory XBM file. Neither width nor
3299 height may be specified in this case because these are defined
3300 in the file.
3301
3302 **** XPM, image type `xpm'
3303
3304 XPM images require the external library `libXpm', package
3305 `xpm-3.4k.tar.gz', version 3.4k or later. Make sure the library is
3306 found when Emacs is configured by supplying appropriate paths via
3307 `--x-includes' and `--x-libraries'.
3308
3309 Additional image properties supported are:
3310
3311 `:color-symbols SYMBOLS'
3312
3313 SYMBOLS must be a list of pairs (NAME . COLOR), with NAME being the
3314 name of color as it appears in an XPM file, and COLOR being an X color
3315 name.
3316
3317 XPM images can be built from memory instead of files. In that case,
3318 add a `:data' property instead of a `:file' property.
3319
3320 The XPM library uses libz in its implementation so that it is able
3321 to display compressed images.
3322
3323 **** PBM, image type `pbm'
3324
3325 PBM images don't require an external library. Color, gray-scale and
3326 mono images are supported. There are no additional image properties
3327 defined.
3328
3329 **** JPEG, image type `jpeg'
3330
3331 Support for JPEG images requires the external library `libjpeg',
3332 package `jpegsrc.v6a.tar.gz', or later. Additional image properties
3333 are:
3334
3335 **** TIFF, image type `tiff'
3336
3337 Support for TIFF images requires the external library `libtiff',
3338 package `tiff-v3.4-tar.gz', or later. There are no additional image
3339 properties defined.
3340
3341 **** GIF, image type `gif'
3342
3343 Support for GIF images requires the external library `libungif', package
3344 `libungif-4.1.0', or later.
3345
3346 Additional image properties supported are:
3347
3348 `:index INDEX'
3349
3350 INDEX must be an integer >= 0. Load image number INDEX from a
3351 multi-image GIF file. An error is signalled if INDEX is too large.
3352
3353 This could be used to implement limited support for animated GIFs.
3354 For example, the following function displays a multi-image GIF file
3355 at point-min in the current buffer, switching between sub-images
3356 every 0.1 seconds.
3357
3358 (defun show-anim (file max)
3359 "Display multi-image GIF file FILE which contains MAX subimages."
3360 (display-anim (current-buffer) file 0 max t))
3361
3362 (defun display-anim (buffer file idx max first-time)
3363 (when (= idx max)
3364 (setq idx 0))
3365 (let ((img (create-image file nil nil :index idx)))
3366 (save-excursion
3367 (set-buffer buffer)
3368 (goto-char (point-min))
3369 (unless first-time (delete-char 1))
3370 (insert-image img "x"))
3371 (run-with-timer 0.1 nil 'display-anim buffer file (1+ idx) max nil)))
3372
3373 **** PNG, image type `png'
3374
3375 Support for PNG images requires the external library `libpng',
3376 package `libpng-1.0.2.tar.gz', or later. There are no additional image
3377 properties defined.
3378
3379 **** Ghostscript, image type `postscript'.
3380
3381 Additional image properties supported are:
3382
3383 `:pt-width WIDTH'
3384
3385 WIDTH is width of the image in pt (1/72 inch). WIDTH must be an
3386 integer. This is a required property.
3387
3388 `:pt-height HEIGHT'
3389
3390 HEIGHT specifies the height of the image in pt (1/72 inch). HEIGHT
3391 must be a integer. This is an required property.
3392
3393 `:bounding-box BOX'
3394
3395 BOX must be a list or vector of 4 integers giving the bounding box of
3396 the PS image, analogous to the `BoundingBox' comment found in PS
3397 files. This is an required property.
3398
3399 Part of the Ghostscript interface is implemented in Lisp. See
3400 lisp/gs.el.
3401
3402 *** Lisp interface.
3403
3404 The variable `image-types' contains a list of those image types
3405 which are supported in the current configuration.
3406
3407 Images are stored in an image cache and removed from the cache when
3408 they haven't been displayed for `image-cache-eviction-delay seconds.
3409 The function `clear-image-cache' can be used to clear the image cache
3410 manually. Images in the cache are compared with `equal', i.e. all
3411 images with `equal' specifications share the same image.
3412
3413 *** Simplified image API, image.el
3414
3415 The new Lisp package image.el contains functions that simplify image
3416 creation and putting images into text. The function `create-image'
3417 can be used to create images. The macro `defimage' can be used to
3418 define an image based on available image types. The functions
3419 `put-image' and `insert-image' can be used to insert an image into a
3420 buffer.
3421
3422 +++
3423 ** Display margins.
3424
3425 Windows can now have margins which are used for special text
3426 and images.
3427
3428 To give a window margins, either set the buffer-local variables
3429 `left-margin-width' and `right-margin-width', or call
3430 `set-window-margins'. The function `window-margins' can be used to
3431 obtain the current settings. To make `left-margin-width' and
3432 `right-margin-width' take effect, you must set them before displaying
3433 the buffer in a window, or use `set-window-buffer' to force an update
3434 of the display margins.
3435
3436 You can put text in margins by giving it a `display' text property
3437 containing a pair of the form `(LOCATION . VALUE)', where LOCATION is
3438 one of `left-margin' or `right-margin' or nil. VALUE can be either a
3439 string, an image specification or a stretch specification (see later
3440 in this file).
3441
3442 +++
3443 ** Help display
3444
3445 Emacs displays short help messages in the echo area, when the mouse
3446 moves over a tool-bar item or a piece of text that has a text property
3447 `help-echo'. This feature also applies to strings in the mode line
3448 that have a `help-echo' property.
3449
3450 If the value of the `help-echo' property is a function, that function
3451 is called with three arguments WINDOW, OBJECT and POSITION. WINDOW is
3452 the window in which the help was found.
3453
3454 If OBJECT is a buffer, POS is the position in the buffer where the
3455 `help-echo' text property was found.
3456
3457 If OBJECT is an overlay, that overlay has a `help-echo' property, and
3458 POS is the position in the overlay's buffer under the mouse.
3459
3460 If OBJECT is a string (an overlay string or a string displayed with
3461 the `display' property), POS is the position in that string under the
3462 mouse.
3463
3464 If the value of the `help-echo' property is neither a function nor a
3465 string, it is evaluated to obtain a help string.
3466
3467 For tool-bar and menu-bar items, their key definition is used to
3468 determine the help to display. If their definition contains a
3469 property `:help FORM', FORM is evaluated to determine the help string.
3470 For tool-bar items without a help form, the caption of the item is
3471 used as help string.
3472
3473 The hook `show-help-function' can be set to a function that displays
3474 the help string differently. For example, enabling a tooltip window
3475 causes the help display to appear there instead of in the echo area.
3476
3477 +++
3478 ** Vertical fractional scrolling.
3479
3480 The display of text in windows can be scrolled smoothly in pixels.
3481 This is useful, for example, for making parts of large images visible.
3482
3483 The function `window-vscroll' returns the current value of vertical
3484 scrolling, a non-negative fraction of the canonical character height.
3485 The function `set-window-vscroll' can be used to set the vertical
3486 scrolling value. Here is an example of how these function might be
3487 used.
3488
3489 (global-set-key [A-down]
3490 #'(lambda ()
3491 (interactive)
3492 (set-window-vscroll (selected-window)
3493 (+ 0.5 (window-vscroll)))))
3494 (global-set-key [A-up]
3495 #'(lambda ()
3496 (interactive)
3497 (set-window-vscroll (selected-window)
3498 (- (window-vscroll) 0.5)))))
3499
3500 +++
3501 ** New hook `fontification-functions'.
3502
3503 Functions from `fontification-functions' are called from redisplay
3504 when it encounters a region of text that is not yet fontified. This
3505 variable automatically becomes buffer-local when set. Each function
3506 is called with one argument, POS.
3507
3508 At least one of the hook functions should fontify one or more
3509 characters starting at POS in the current buffer. It should mark them
3510 as fontified by giving them a non-nil value of the `fontified' text
3511 property. It may be reasonable for these functions to check for the
3512 `fontified' property and not put it back on, but they do not have to.
3513
3514 +++
3515 ** Tool bar support.
3516
3517 Emacs supports a tool bar at the top of a frame under X. The frame
3518 parameter `tool-bar-lines' (X resource "toolBar", class "ToolBar")
3519 controls how may lines to reserve for the tool bar. A zero value
3520 suppresses the tool bar. If the value is non-zero and
3521 `auto-resize-tool-bars' is non-nil the tool bar's size will be changed
3522 automatically so that all tool bar items are visible.
3523
3524 *** Tool bar item definitions
3525
3526 Tool bar items are defined using `define-key' with a prefix-key
3527 `tool-bar'. For example `(define-key global-map [tool-bar item1] ITEM)'
3528 where ITEM is a list `(menu-item CAPTION BINDING PROPS...)'.
3529
3530 CAPTION is the caption of the item, If it's not a string, it is
3531 evaluated to get a string. The caption is currently not displayed in
3532 the tool bar, but it is displayed if the item doesn't have a `:help'
3533 property (see below).
3534
3535 BINDING is the tool bar item's binding. Tool bar items with keymaps as
3536 binding are currently ignored.
3537
3538 The following properties are recognized:
3539
3540 `:enable FORM'.
3541
3542 FORM is evaluated and specifies whether the tool bar item is enabled
3543 or disabled.
3544
3545 `:visible FORM'
3546
3547 FORM is evaluated and specifies whether the tool bar item is displayed.
3548
3549 `:filter FUNCTION'
3550
3551 FUNCTION is called with one parameter, the same list BINDING in which
3552 FUNCTION is specified as the filter. The value FUNCTION returns is
3553 used instead of BINDING to display this item.
3554
3555 `:button (TYPE SELECTED)'
3556
3557 TYPE must be one of `:radio' or `:toggle'. SELECTED is evaluated
3558 and specifies whether the button is selected (pressed) or not.
3559
3560 `:image IMAGES'
3561
3562 IMAGES is either a single image specification or a vector of four
3563 image specifications. If it is a vector, this table lists the
3564 meaning of each of the four elements:
3565
3566 Index Use when item is
3567 ----------------------------------------
3568 0 enabled and selected
3569 1 enabled and deselected
3570 2 disabled and selected
3571 3 disabled and deselected
3572
3573 If IMAGE is a single image specification, a Laplace edge-detection
3574 algorithm is used on that image to draw the image in disabled state.
3575
3576 `:help HELP-STRING'.
3577
3578 Gives a help string to display for the tool bar item. This help
3579 is displayed when the mouse is moved over the item.
3580
3581 The function `toolbar-add-item' is a convenience function for adding
3582 toolbar items generally, and `tool-bar-add-item-from-menu' can be used
3583 to define a toolbar item with a binding copied from an item on the
3584 menu bar.
3585
3586 *** Tool-bar-related variables.
3587
3588 If `auto-resize-tool-bar' is non-nil, the tool bar will automatically
3589 resize to show all defined tool bar items. It will never grow larger
3590 than 1/4 of the frame's size.
3591
3592 If `auto-raise-tool-bar-buttons' is non-nil, tool bar buttons will be
3593 raised when the mouse moves over them.
3594
3595 You can add extra space between tool bar items by setting
3596 `tool-bar-button-margin' to a positive integer specifying a number of
3597 pixels. Default is 1.
3598
3599 You can change the shadow thickness of tool bar buttons by setting
3600 `tool-bar-button-relief' to an integer. Default is 3.
3601
3602 *** Tool-bar clicks with modifiers.
3603
3604 You can bind commands to clicks with control, shift, meta etc. on
3605 a tool bar item. If
3606
3607 (define-key global-map [tool-bar shell]
3608 '(menu-item "Shell" shell
3609 :image (image :type xpm :file "shell.xpm")))
3610
3611 is the original tool bar item definition, then
3612
3613 (define-key global-map [tool-bar S-shell] 'some-command)
3614
3615 makes a binding to run `some-command' for a shifted click on the same
3616 item.
3617
3618 ** Mode line changes.
3619
3620 +++
3621 *** Mouse-sensitive mode line.
3622
3623 The mode line can be made mouse-sensitive by displaying strings there
3624 that have a `local-map' text property. There are three ways to display
3625 a string with a `local-map' property in the mode line.
3626
3627 1. The mode line spec contains a variable whose string value has
3628 a `local-map' text property.
3629
3630 2. The mode line spec contains a format specifier (e.g. `%12b'), and
3631 that format specifier has a `local-map' property.
3632
3633 3. The mode line spec contains a list containing `:eval FORM'. FORM
3634 is evaluated. If the result is a string, and that string has a
3635 `local-map' property.
3636
3637 The same mechanism is used to determine the `face' and `help-echo'
3638 properties of strings in the mode line. See `bindings.el' for an
3639 example.
3640
3641 *** If a mode line element has the form `(:eval FORM)', FORM is
3642 evaluated and the result is used as mode line element.
3643
3644 +++
3645 *** You can suppress mode-line display by setting the buffer-local
3646 variable mode-line-format to nil.
3647
3648 +++
3649 *** A headerline can now be displayed at the top of a window.
3650
3651 This mode line's contents are controlled by the new variable
3652 `header-line-format' and `default-header-line-format' which are
3653 completely analogous to `mode-line-format' and
3654 `default-mode-line-format'. A value of nil means don't display a top
3655 line.
3656
3657 The appearance of top mode lines is controlled by the face
3658 `header-line'.
3659
3660 The function `coordinates-in-window-p' returns `header-line' for a
3661 position in the header-line.
3662
3663 +++
3664 ** Text property `display'
3665
3666 The `display' text property is used to insert images into text,
3667 replace text with other text, display text in marginal area, and it is
3668 also used to control other aspects of how text displays. The value of
3669 the `display' property should be a display specification, as described
3670 below, or a list or vector containing display specifications.
3671
3672 *** Replacing text, displaying text in marginal areas
3673
3674 To replace the text having the `display' property with some other
3675 text, use a display specification of the form `(LOCATION STRING)'.
3676
3677 If LOCATION is `(margin left-margin)', STRING is displayed in the left
3678 marginal area, if it is `(margin right-margin)', it is displayed in
3679 the right marginal area, and if LOCATION is `(margin nil)' STRING
3680 is displayed in the text. In the latter case you can also use the
3681 simpler form STRING as property value.
3682
3683 *** Variable width and height spaces
3684
3685 To display a space of fractional width or height, use a display
3686 specification of the form `(LOCATION STRECH)'. If LOCATION is
3687 `(margin left-margin)', the space is displayed in the left marginal
3688 area, if it is `(margin right-margin)', it is displayed in the right
3689 marginal area, and if LOCATION is `(margin nil)' the space is
3690 displayed in the text. In the latter case you can also use the
3691 simpler form STRETCH as property value.
3692
3693 The stretch specification STRETCH itself is a list of the form `(space
3694 PROPS)', where PROPS is a property list which can contain the
3695 properties described below.
3696
3697 The display of the fractional space replaces the display of the
3698 characters having the `display' property.
3699
3700 - :width WIDTH
3701
3702 Specifies that the space width should be WIDTH times the normal
3703 character width. WIDTH can be an integer or floating point number.
3704
3705 - :relative-width FACTOR
3706
3707 Specifies that the width of the stretch should be computed from the
3708 first character in a group of consecutive characters that have the
3709 same `display' property. The computation is done by multiplying the
3710 width of that character by FACTOR.
3711
3712 - :align-to HPOS
3713
3714 Specifies that the space should be wide enough to reach HPOS. The
3715 value HPOS is measured in units of the normal character width.
3716
3717 Exactly one of the above properties should be used.
3718
3719 - :height HEIGHT
3720
3721 Specifies the height of the space, as HEIGHT, measured in terms of the
3722 normal line height.
3723
3724 - :relative-height FACTOR
3725
3726 The height of the space is computed as the product of the height
3727 of the text having the `display' property and FACTOR.
3728
3729 - :ascent ASCENT
3730
3731 Specifies that ASCENT percent of the height of the stretch should be
3732 used for the ascent of the stretch, i.e. for the part above the
3733 baseline. The value of ASCENT must be a non-negative number less or
3734 equal to 100.
3735
3736 You should not use both `:height' and `:relative-height' together.
3737
3738 *** Images
3739
3740 A display specification for an image has the form `(LOCATION
3741 . IMAGE)', where IMAGE is an image specification. The image replaces,
3742 in the display, the characters having this display specification in
3743 their `display' text property. If LOCATION is `(margin left-margin)',
3744 the image will be displayed in the left marginal area, if it is
3745 `(margin right-margin)' it will be displayed in the right marginal
3746 area, and if LOCATION is `(margin nil)' the image will be displayed in
3747 the text. In the latter case you can also use the simpler form IMAGE
3748 as display specification.
3749
3750 *** Other display properties
3751
3752 - :space-width FACTOR
3753
3754 Specifies that space characters in the text having that property
3755 should be displayed FACTOR times as wide as normal; FACTOR must be an
3756 integer or float.
3757
3758 - :height HEIGHT
3759
3760 Display text having this property in a font that is smaller or larger.
3761
3762 If HEIGHT is a list of the form `(+ N)', where N is an integer, that
3763 means to use a font that is N steps larger. If HEIGHT is a list of
3764 the form `(- N)', that means to use a font that is N steps smaller. A
3765 ``step'' is defined by the set of available fonts; each size for which
3766 a font is available counts as a step.
3767
3768 If HEIGHT is a number, that means to use a font that is HEIGHT times
3769 as tall as the frame's default font.
3770
3771 If HEIGHT is a symbol, it is called as a function with the current
3772 height as argument. The function should return the new height to use.
3773
3774 Otherwise, HEIGHT is evaluated to get the new height, with the symbol
3775 `height' bound to the current specified font height.
3776
3777 - :raise FACTOR
3778
3779 FACTOR must be a number, specifying a multiple of the current
3780 font's height. If it is positive, that means to display the characters
3781 raised. If it is negative, that means to display them lower down. The
3782 amount of raising or lowering is computed without taking account of the
3783 `:height' subproperty.
3784
3785 *** Conditional display properties
3786
3787 All display specifications can be conditionalized. If a specification
3788 has the form `(:when CONDITION . SPEC)', the specification SPEC
3789 applies only when CONDITION yields a non-nil value when evaluated.
3790 During evaluattion, point is temporarily set to the end position of
3791 the text having the `display' property.
3792
3793 The normal specification consisting of SPEC only is equivalent to
3794 `(:when t SPEC)'.
3795
3796 +++
3797 ** New menu separator types.
3798
3799 Emacs now supports more than one menu separator type. Menu items with
3800 item names consisting of dashes only (including zero dashes) are
3801 treated like before. In addition, the following item names are used
3802 to specify other menu separator types.
3803
3804 - `--no-line' or `--space', or `--:space', or `--:noLine'
3805
3806 No separator lines are drawn, but a small space is inserted where the
3807 separator occurs.
3808
3809 - `--single-line' or `--:singleLine'
3810
3811 A single line in the menu's foreground color.
3812
3813 - `--double-line' or `--:doubleLine'
3814
3815 A double line in the menu's foreground color.
3816
3817 - `--single-dashed-line' or `--:singleDashedLine'
3818
3819 A single dashed line in the menu's foreground color.
3820
3821 - `--double-dashed-line' or `--:doubleDashedLine'
3822
3823 A double dashed line in the menu's foreground color.
3824
3825 - `--shadow-etched-in' or `--:shadowEtchedIn'
3826
3827 A single line with 3D sunken appearance. This is the the form
3828 displayed for item names consisting of dashes only.
3829
3830 - `--shadow-etched-out' or `--:shadowEtchedOut'
3831
3832 A single line with 3D raised appearance.
3833
3834 - `--shadow-etched-in-dash' or `--:shadowEtchedInDash'
3835
3836 A single dashed line with 3D sunken appearance.
3837
3838 - `--shadow-etched-out-dash' or `--:shadowEtchedOutDash'
3839
3840 A single dashed line with 3D raise appearance.
3841
3842 - `--shadow-double-etched-in' or `--:shadowDoubleEtchedIn'
3843
3844 Two lines with 3D sunken appearance.
3845
3846 - `--shadow-double-etched-out' or `--:shadowDoubleEtchedOut'
3847
3848 Two lines with 3D raised appearance.
3849
3850 - `--shadow-double-etched-in-dash' or `--:shadowDoubleEtchedInDash'
3851
3852 Two dashed lines with 3D sunken appearance.
3853
3854 - `--shadow-double-etched-out-dash' or `--:shadowDoubleEtchedOutDash'
3855
3856 Two dashed lines with 3D raised appearance.
3857
3858 Under LessTif/Motif, the last four separator types are displayed like
3859 the corresponding single-line separators.
3860
3861 +++
3862 ** New frame parameters for scroll bar colors.
3863
3864 The new frame parameters `scroll-bar-foreground' and
3865 `scroll-bar-background' can be used to change scroll bar colors.
3866 Their value must be either a color name, a string, or nil to specify
3867 that scroll bars should use a default color. For toolkit scroll bars,
3868 default colors are toolkit specific. For non-toolkit scroll bars, the
3869 default background is the background color of the frame, and the
3870 default foreground is black.
3871
3872 The X resource name of these parameters are `scrollBarForeground'
3873 (class ScrollBarForeground) and `scrollBarBackground' (class
3874 `ScrollBarBackground').
3875
3876 Setting these parameters overrides toolkit specific X resource
3877 settings for scroll bar colors.
3878
3879 +++
3880 ** You can set `redisplay-dont-pause' to a non-nil value to prevent
3881 display updates from being interrupted when input is pending.
3882
3883 ---
3884 ** Changing a window's width may now change its window start if it
3885 starts on a continuation line. The new window start is computed based
3886 on the window's new width, starting from the start of the continued
3887 line as the start of the screen line with the minimum distance from
3888 the original window start.
3889
3890 ---
3891 ** The variable `hscroll-step' and the functions
3892 `hscroll-point-visible' and `hscroll-window-column' have been removed
3893 now that proper horizontal scrolling is implemented.
3894
3895 +++
3896 ** Windows can now be made fixed-width and/or fixed-height.
3897
3898 A window is fixed-size if its buffer has a buffer-local variable
3899 `window-size-fixed' whose value is not nil. A value of `height' makes
3900 windows fixed-height, a value of `width' makes them fixed-width, any
3901 other non-nil value makes them both fixed-width and fixed-height.
3902
3903 The following code makes all windows displaying the current buffer
3904 fixed-width and fixed-height.
3905
3906 (set (make-local-variable 'window-size-fixed) t)
3907
3908 A call to enlarge-window on a window gives an error if that window is
3909 fixed-width and it is tried to change the window's width, or if the
3910 window is fixed-height, and it is tried to change its height. To
3911 change the size of a fixed-size window, bind `window-size-fixed'
3912 temporarily to nil, for example
3913
3914 (let ((window-size-fixed nil))
3915 (enlarge-window 10))
3916
3917 Likewise, an attempt to split a fixed-height window vertically,
3918 or a fixed-width window horizontally results in a error.
3919
3920 ** The cursor-type frame parameter is now supported on MS-DOS
3921 terminals. When Emacs starts, it by default changes the cursor shape
3922 to a solid box, as it does on Unix. The `cursor-type' frame parameter
3923 overrides this as it does on Unix, except that the bar cursor is
3924 horizontal rather than vertical (since the MS-DOS display doesn't
3925 support a vertical-bar cursor).
3926
3927
3928 ^L
3929 * Emacs 20.7 is a bug-fix release with few user-visible changes
3930
3931 ** It is now possible to use CCL-based coding systems for keyboard
3932 input.
3933
3934 ** ange-ftp now handles FTP security extensions, like Kerberos.
3935
3936 ** Rmail has been extended to recognize more forms of digest messages.
3937
3938 ** Now, most coding systems set in keyboard coding system work not
3939 only for character input, but also in incremental search. The
3940 exceptions are such coding systems that handle 2-byte character sets
3941 (e.g euc-kr, euc-jp) and that use ISO's escape sequence
3942 (e.g. iso-2022-jp). They are ignored in incremental search.
3943
3944 ** Support for Macintosh PowerPC-based machines running GNU/Linux has
3945 been added.
3946
3947 ^L
3948 * Emacs 20.6 is a bug-fix release with one user-visible change
3949
3950 ** Support for ARM-based non-RISCiX machines has been added.
3951
3952 ^L
3953 * Emacs 20.5 is a bug-fix release with no user-visible changes.
3954
3955 ** Not new, but not mentioned before:
3956 M-w when Transient Mark mode is enabled disables the mark.
3957 \f
3958 * Changes in Emacs 20.4
3959
3960 ** Init file may be called .emacs.el.
3961
3962 You can now call the Emacs init file `.emacs.el'.
3963 Formerly the name had to be `.emacs'. If you use the name
3964 `.emacs.el', you can byte-compile the file in the usual way.
3965
3966 If both `.emacs' and `.emacs.el' exist, the latter file
3967 is the one that is used.
3968
3969 ** shell-command, and shell-command-on-region, now return
3970 the exit code of the command (unless it is asynchronous).
3971 Also, you can specify a place to put the error output,
3972 separate from the command's regular output.
3973 Interactively, the variable shell-command-default-error-buffer
3974 says where to put error output; set it to a buffer name.
3975 In calls from Lisp, an optional argument ERROR-BUFFER specifies
3976 the buffer name.
3977
3978 When you specify a non-nil error buffer (or buffer name), any error
3979 output is inserted before point in that buffer, with \f\n to separate
3980 it from the previous batch of error output. The error buffer is not
3981 cleared, so error output from successive commands accumulates there.
3982
3983 ** Setting the default value of enable-multibyte-characters to nil in
3984 the .emacs file, either explicitly using setq-default, or via Custom,
3985 is now essentially equivalent to using --unibyte: all buffers
3986 created during startup will be made unibyte after loading .emacs.
3987
3988 ** C-x C-f now handles the wildcards * and ? in file names. For
3989 example, typing C-x C-f c*.c RET visits all the files whose names
3990 match c*.c. To visit a file whose name contains * or ?, add the
3991 quoting sequence /: to the beginning of the file name.
3992
3993 ** The M-x commands keep-lines, flush-lines and count-matches
3994 now have the same feature as occur and query-replace:
3995 if the pattern contains any upper case letters, then
3996 they never ignore case.
3997
3998 ** The end-of-line format conversion feature previously mentioned
3999 under `* Emacs 20.1 changes for MS-DOS and MS-Windows' actually
4000 applies to all operating systems. Emacs recognizes from the contents
4001 of a file what convention it uses to separate lines--newline, CRLF, or
4002 just CR--and automatically converts the contents to the normal Emacs
4003 convention (using newline to separate lines) for editing. This is a
4004 part of the general feature of coding system conversion.
4005
4006 If you subsequently save the buffer, Emacs converts the text back to
4007 the same format that was used in the file before.
4008
4009 You can turn off end-of-line conversion by setting the variable
4010 `inhibit-eol-conversion' to non-nil, e.g. with Custom in the MULE group.
4011
4012 ** The character set property `prefered-coding-system' has been
4013 renamed to `preferred-coding-system', for the sake of correct spelling.
4014 This is a fairly internal feature, so few programs should be affected.
4015
4016 ** Mode-line display of end-of-line format is changed.
4017 The indication of the end-of-line format of the file visited by a
4018 buffer is now more explicit when that format is not the usual one for
4019 your operating system. For example, the DOS-style end-of-line format
4020 is displayed as "(DOS)" on Unix and GNU/Linux systems. The usual
4021 end-of-line format is still displayed as a single character (colon for
4022 Unix, backslash for DOS and Windows, and forward slash for the Mac).
4023
4024 The values of the variables eol-mnemonic-unix, eol-mnemonic-dos,
4025 eol-mnemonic-mac, and eol-mnemonic-undecided, which are strings,
4026 control what is displayed in the mode line for each end-of-line
4027 format. You can now customize these variables.
4028
4029 ** In the previous version of Emacs, tar-mode didn't work well if a
4030 filename contained non-ASCII characters. Now this is fixed. Such a
4031 filename is decoded by file-name-coding-system if the default value of
4032 enable-multibyte-characters is non-nil.
4033
4034 ** The command temp-buffer-resize-mode toggles a minor mode
4035 in which temporary buffers (such as help buffers) are given
4036 windows just big enough to hold the whole contents.
4037
4038 ** If you use completion.el, you must now run the function
4039 dynamic-completion-mode to enable it. Just loading the file
4040 doesn't have any effect.
4041
4042 ** In Flyspell mode, the default is now to make just one Ispell process,
4043 not one per buffer.
4044
4045 ** If you use iswitchb but do not call (iswitchb-default-keybindings) to
4046 use the default keybindings, you will need to add the following line:
4047 (add-hook 'minibuffer-setup-hook 'iswitchb-minibuffer-setup)
4048
4049 ** Auto-show mode is no longer enabled just by loading auto-show.el.
4050 To control it, set `auto-show-mode' via Custom or use the
4051 `auto-show-mode' command.
4052
4053 ** Handling of X fonts' ascent/descent parameters has been changed to
4054 avoid redisplay problems. As a consequence, compared with previous
4055 versions the line spacing and frame size now differ with some font
4056 choices, typically increasing by a pixel per line. This change
4057 occurred in version 20.3 but was not documented then.
4058
4059 ** If you select the bar cursor style, it uses the frame's
4060 cursor-color, rather than the cursor foreground pixel.
4061
4062 ** In multibyte mode, Rmail decodes incoming MIME messages using the
4063 character set specified in the message. If you want to disable this
4064 feature, set the variable rmail-decode-mime-charset to nil.
4065
4066 ** Not new, but not mentioned previously in NEWS: when you use #! at
4067 the beginning of a file to make it executable and specify an
4068 interpreter program, Emacs looks on the second line for the -*- mode
4069 and variable specification, as well as on the first line.
4070
4071 ** Support for IBM codepage encoding of non-ASCII characters.
4072
4073 The new command M-x codepage-setup creates a special coding system
4074 that can be used to convert text between a specific IBM codepage and
4075 one of the character sets built into Emacs which matches that
4076 codepage. For example, codepage 850 corresponds to Latin-1 character
4077 set, codepage 855 corresponds to Cyrillic-ISO character set, etc.
4078
4079 Windows codepages 1250, 1251 and some others, where Windows deviates
4080 from the corresponding ISO character set, are also supported.
4081
4082 IBM box-drawing characters and other glyphs which don't have
4083 equivalents in the corresponding ISO character set, are converted to
4084 a character defined by dos-unsupported-char-glyph on MS-DOS, and to
4085 `?' on other systems.
4086
4087 IBM codepages are widely used on MS-DOS and MS-Windows, so this
4088 feature is most useful on those platforms, but it can also be used on
4089 Unix.
4090
4091 Emacs compiled for MS-DOS automatically loads the support for the
4092 current codepage when it starts.
4093
4094 ** Mail changes
4095
4096 *** When mail is sent using compose-mail (C-x m), and if
4097 `mail-send-nonascii' is set to the new default value `mime',
4098 appropriate MIME headers are added. The headers are added only if
4099 non-ASCII characters are present in the body of the mail, and no other
4100 MIME headers are already present. For example, the following three
4101 headers are added if the coding system used in the *mail* buffer is
4102 latin-1:
4103
4104 MIME-version: 1.0
4105 Content-type: text/plain; charset=iso-8859-1
4106 Content-Transfer-Encoding: 8bit
4107
4108 *** The new variable default-sendmail-coding-system specifies the
4109 default way to encode outgoing mail. This has higher priority than
4110 default-buffer-file-coding-system but has lower priority than
4111 sendmail-coding-system and the local value of
4112 buffer-file-coding-system.
4113
4114 You should not set this variable manually. Instead, set
4115 sendmail-coding-system to specify a fixed encoding for all outgoing
4116 mail.
4117
4118 *** When you try to send a message that contains non-ASCII characters,
4119 if the coding system specified by those variables doesn't handle them,
4120 Emacs will ask you to select a suitable coding system while showing a
4121 list of possible coding systems.
4122
4123 ** CC Mode changes
4124
4125 *** c-default-style can now take an association list that maps major
4126 modes to style names. When this variable is an alist, Java mode no
4127 longer hardcodes a setting to "java" style. See the variable's
4128 docstring for details.
4129
4130 *** It's now possible to put a list as the offset on a syntactic
4131 symbol. The list is evaluated recursively until a non-nil offset is
4132 found. This is useful to combine several lineup functions to act in a
4133 prioritized order on a single line. However, none of the supplied
4134 lineup functions use this feature currently.
4135
4136 *** New syntactic symbol catch-clause, which is used on the "catch" and
4137 "finally" lines in try-catch constructs in C++ and Java.
4138
4139 *** New cleanup brace-catch-brace on c-cleanup-list, which does for
4140 "catch" lines what brace-elseif-brace does for "else if" lines.
4141
4142 *** The braces of Java anonymous inner classes are treated separately
4143 from the braces of other classes in auto-newline mode. Two new
4144 symbols inexpr-class-open and inexpr-class-close may be used on
4145 c-hanging-braces-alist to control the automatic newlines used for
4146 anonymous classes.
4147
4148 *** Support for the Pike language added, along with new Pike specific
4149 syntactic symbols: inlambda, lambda-intro-cont
4150
4151 *** Support for Java anonymous classes via new syntactic symbol
4152 inexpr-class. New syntactic symbol inexpr-statement for Pike
4153 support and gcc-style statements inside expressions. New lineup
4154 function c-lineup-inexpr-block.
4155
4156 *** New syntactic symbol brace-entry-open which is used in brace lists
4157 (i.e. static initializers) when a list entry starts with an open
4158 brace. These used to be recognized as brace-list-entry's.
4159 c-electric-brace also recognizes brace-entry-open braces
4160 (brace-list-entry's can no longer be electrified).
4161
4162 *** New command c-indent-line-or-region, not bound by default.
4163
4164 *** `#' is only electric when typed in the indentation of a line.
4165
4166 *** Parentheses are now electric (via the new command c-electric-paren)
4167 for auto-reindenting lines when parens are typed.
4168
4169 *** In "gnu" style, inline-open offset is now set to zero.
4170
4171 *** Uniform handling of the inclass syntactic symbol. The indentation
4172 associated with it is now always relative to the class opening brace.
4173 This means that the indentation behavior has changed in some
4174 circumstances, but only if you've put anything besides 0 on the
4175 class-open syntactic symbol (none of the default styles do that).
4176
4177 ** Gnus changes.
4178
4179 *** New functionality for using Gnus as an offline newsreader has been
4180 added. A plethora of new commands and modes have been added. See the
4181 Gnus manual for the full story.
4182
4183 *** The nndraft backend has returned, but works differently than
4184 before. All Message buffers are now also articles in the nndraft
4185 group, which is created automatically.
4186
4187 *** `gnus-alter-header-function' can now be used to alter header
4188 values.
4189
4190 *** `gnus-summary-goto-article' now accept Message-ID's.
4191
4192 *** A new Message command for deleting text in the body of a message
4193 outside the region: `C-c C-v'.
4194
4195 *** You can now post to component group in nnvirtual groups with
4196 `C-u C-c C-c'.
4197
4198 *** `nntp-rlogin-program' -- new variable to ease customization.
4199
4200 *** `C-u C-c C-c' in `gnus-article-edit-mode' will now inhibit
4201 re-highlighting of the article buffer.
4202
4203 *** New element in `gnus-boring-article-headers' -- `long-to'.
4204
4205 *** `M-i' symbolic prefix command. See the section "Symbolic
4206 Prefixes" in the Gnus manual for details.
4207
4208 *** `L' and `I' in the summary buffer now take the symbolic prefix
4209 `a' to add the score rule to the "all.SCORE" file.
4210
4211 *** `gnus-simplify-subject-functions' variable to allow greater
4212 control over simplification.
4213
4214 *** `A T' -- new command for fetching the current thread.
4215
4216 *** `/ T' -- new command for including the current thread in the
4217 limit.
4218
4219 *** `M-RET' is a new Message command for breaking cited text.
4220
4221 *** \\1-expressions are now valid in `nnmail-split-methods'.
4222
4223 *** The `custom-face-lookup' function has been removed.
4224 If you used this function in your initialization files, you must
4225 rewrite them to use `face-spec-set' instead.
4226
4227 *** Cancelling now uses the current select method. Symbolic prefix
4228 `a' forces normal posting method.
4229
4230 *** New command to translate M******** sm*rtq**t*s into proper text
4231 -- `W d'.
4232
4233 *** For easier debugging of nntp, you can set `nntp-record-commands'
4234 to a non-nil value.
4235
4236 *** nntp now uses ~/.authinfo, a .netrc-like file, for controlling
4237 where and how to send AUTHINFO to NNTP servers.
4238
4239 *** A command for editing group parameters from the summary buffer
4240 has been added.
4241
4242 *** A history of where mails have been split is available.
4243
4244 *** A new article date command has been added -- `article-date-iso8601'.
4245
4246 *** Subjects can be simplified when threading by setting
4247 `gnus-score-thread-simplify'.
4248
4249 *** A new function for citing in Message has been added --
4250 `message-cite-original-without-signature'.
4251
4252 *** `article-strip-all-blank-lines' -- new article command.
4253
4254 *** A new Message command to kill to the end of the article has
4255 been added.
4256
4257 *** A minimum adaptive score can be specified by using the
4258 `gnus-adaptive-word-minimum' variable.
4259
4260 *** The "lapsed date" article header can be kept continually
4261 updated by the `gnus-start-date-timer' command.
4262
4263 *** Web listserv archives can be read with the nnlistserv backend.
4264
4265 *** Old dejanews archives can now be read by nnweb.
4266
4267 *** `gnus-posting-styles' has been re-activated.
4268
4269 ** Changes to TeX and LaTeX mode
4270
4271 *** The new variable `tex-start-options-string' can be used to give
4272 options for the TeX run. The default value causes TeX to run in
4273 nonstopmode. For an interactive TeX run set it to nil or "".
4274
4275 *** The command `tex-feed-input' sends input to the Tex Shell. In a
4276 TeX buffer it is bound to the keys C-RET, C-c RET, and C-c C-m (some
4277 of these keys may not work on all systems). For instance, if you run
4278 TeX interactively and if the TeX run stops because of an error, you
4279 can continue it without leaving the TeX buffer by typing C-RET.
4280
4281 *** The Tex Shell Buffer is now in `compilation-shell-minor-mode'.
4282 All error-parsing commands of the Compilation major mode are available
4283 but bound to keys that don't collide with the shell. Thus you can use
4284 the Tex Shell for command line executions like a usual shell.
4285
4286 *** The commands `tex-validate-region' and `tex-validate-buffer' check
4287 the matching of braces and $'s. The errors are listed in a *Occur*
4288 buffer and you can use C-c C-c or mouse-2 to go to a particular
4289 mismatch.
4290
4291 ** Changes to RefTeX mode
4292
4293 *** The table of contents buffer can now also display labels and
4294 file boundaries in addition to sections. Use `l', `i', and `c' keys.
4295
4296 *** Labels derived from context (the section heading) are now
4297 lowercase by default. To make the label legal in LaTeX, latin-1
4298 characters will lose their accent. All Mule characters will be
4299 removed from the label.
4300
4301 *** The automatic display of cross reference information can also use
4302 a window instead of the echo area. See variable `reftex-auto-view-crossref'.
4303
4304 *** kpsewhich can be used by RefTeX to find TeX and BibTeX files. See the
4305 customization group `reftex-finding-files'.
4306
4307 *** The option `reftex-bibfile-ignore-list' has been renamed to
4308 `reftex-bibfile-ignore-regexps' and indeed can be fed with regular
4309 expressions.
4310
4311 *** Multiple Selection buffers are now hidden buffers.
4312
4313 ** New/deleted modes and packages
4314
4315 *** The package snmp-mode.el provides major modes for editing SNMP and
4316 SNMPv2 MIBs. It has entries on `auto-mode-alist'.
4317
4318 *** The package sql.el provides a major mode, M-x sql-mode, for
4319 editing SQL files, and M-x sql-interactive-mode for interacting with
4320 SQL interpreters. It has an entry on `auto-mode-alist'.
4321
4322 *** M-x highlight-changes-mode provides a minor mode displaying buffer
4323 changes with a special face.
4324
4325 *** ispell4.el has been deleted. It got in the way of ispell.el and
4326 this was hard to fix reliably. It has long been obsolete -- use
4327 Ispell 3.1 and ispell.el.
4328 \f
4329 * MS-DOS changes in Emacs 20.4
4330
4331 ** Emacs compiled for MS-DOS now supports MULE features better.
4332 This includes support for display of all ISO 8859-N character sets,
4333 conversion to and from IBM codepage encoding of non-ASCII characters,
4334 and automatic setup of the MULE environment at startup. For details,
4335 check out the section `MS-DOS and MULE' in the manual.
4336
4337 The MS-DOS installation procedure automatically configures and builds
4338 Emacs with input method support if it finds an unpacked Leim
4339 distribution when the config.bat script is run.
4340
4341 ** Formerly, the value of lpr-command did not affect printing on
4342 MS-DOS unless print-region-function was set to nil, but now it
4343 controls whether an external program is invoked or output is written
4344 directly to a printer port. Similarly, in the previous version of
4345 Emacs, the value of ps-lpr-command did not affect PostScript printing
4346 on MS-DOS unless ps-printer-name was set to something other than a
4347 string (eg. t or `pipe'), but now it controls whether an external
4348 program is used. (These changes were made so that configuration of
4349 printing variables would be almost identical across all platforms.)
4350
4351 ** In the previous version of Emacs, PostScript and non-PostScript
4352 output was piped to external programs, but because most print programs
4353 available for MS-DOS and MS-Windows cannot read data from their standard
4354 input, on those systems the data to be output is now written to a
4355 temporary file whose name is passed as the last argument to the external
4356 program.
4357
4358 An exception is made for `print', a standard program on Windows NT,
4359 and `nprint', a standard program on Novell Netware. For both of these
4360 programs, the command line is constructed in the appropriate syntax
4361 automatically, using only the value of printer-name or ps-printer-name
4362 as appropriate--the value of the relevant `-switches' variable is
4363 ignored, as both programs have no useful switches.
4364
4365 ** The value of the variable dos-printer (cf. dos-ps-printer), if it has
4366 a value, overrides the value of printer-name (cf. ps-printer-name), on
4367 MS-DOS and MS-Windows only. This has been true since version 20.3, but
4368 was not documented clearly before.
4369
4370 ** All the Emacs games now work on MS-DOS terminals.
4371 This includes Tetris and Snake.
4372 \f
4373 * Lisp changes in Emacs 20.4
4374
4375 ** New functions line-beginning-position and line-end-position
4376 return the position of the beginning or end of the current line.
4377 They both accept an optional argument, which has the same
4378 meaning as the argument to beginning-of-line or end-of-line.
4379
4380 ** find-file and allied functions now have an optional argument
4381 WILDCARD. If this is non-nil, they do wildcard processing,
4382 and visit all files that match the wildcard pattern.
4383
4384 ** Changes in the file-attributes function.
4385
4386 *** The file size returned by file-attributes may be an integer or a float.
4387 It is an integer if the size fits in a Lisp integer, float otherwise.
4388
4389 *** The inode number returned by file-attributes may be an integer (if
4390 the number fits in a Lisp integer) or a cons cell containing two
4391 integers.
4392
4393 ** The new function directory-files-and-attributes returns a list of
4394 files in a directory and their attributes. It accepts the same
4395 arguments as directory-files and has similar semantics, except that
4396 file names and attributes are returned.
4397
4398 ** The new function file-attributes-lessp is a helper function for
4399 sorting the list generated by directory-files-and-attributes. It
4400 accepts two arguments, each a list of a file name and its atttributes.
4401 It compares the file names of each according to string-lessp and
4402 returns the result.
4403
4404 ** The new function file-expand-wildcards expands a wildcard-pattern
4405 to produce a list of existing files that match the pattern.
4406
4407 ** New functions for base64 conversion:
4408
4409 The function base64-encode-region converts a part of the buffer
4410 into the base64 code used in MIME. base64-decode-region
4411 performs the opposite conversion. Line-breaking is supported
4412 optionally.
4413
4414 Functions base64-encode-string and base64-decode-string do a similar
4415 job on the text in a string. They return the value as a new string.
4416
4417 **
4418 The new function process-running-child-p
4419 will tell you if a subprocess has given control of its
4420 terminal to its own child process.
4421
4422 ** interrupt-process and such functions have a new feature:
4423 when the second argument is `lambda', they send a signal
4424 to the running child of the subshell, if any, but if the shell
4425 itself owns its terminal, no signal is sent.
4426
4427 ** There are new widget types `plist' and `alist' which can
4428 be used for customizing variables whose values are plists or alists.
4429
4430 ** easymenu.el Now understands `:key-sequence' and `:style button'.
4431 :included is an alias for :visible.
4432
4433 easy-menu-add-item now understands the values returned by
4434 easy-menu-remove-item and easy-menu-item-present-p. This can be used
4435 to move or copy menu entries.
4436
4437 ** Multibyte editing changes
4438
4439 *** The definitions of sref and char-bytes are changed. Now, sref is
4440 an alias of aref and char-bytes always returns 1. This change is to
4441 make some Emacs Lisp code which works on 20.2 and earlier also
4442 work on the latest Emacs. Such code uses a combination of sref and
4443 char-bytes in a loop typically as below:
4444 (setq char (sref str idx)
4445 idx (+ idx (char-bytes idx)))
4446 The byte-compiler now warns that this is obsolete.
4447
4448 If you want to know how many bytes a specific multibyte character
4449 (say, CH) occupies in a multibyte buffer, use this code:
4450 (charset-bytes (char-charset ch))
4451
4452 *** In multibyte mode, when you narrow a buffer to some region, and the
4453 region is preceded or followed by non-ASCII codes, inserting or
4454 deleting at the head or the end of the region may signal this error:
4455
4456 Byte combining across boundary of accessible buffer text inhibitted
4457
4458 This is to avoid some bytes being combined together into a character
4459 across the boundary.
4460
4461 *** The functions find-charset-region and find-charset-string include
4462 `unknown' in the returned list in the following cases:
4463 o The current buffer or the target string is unibyte and
4464 contains 8-bit characters.
4465 o The current buffer or the target string is multibyte and
4466 contains invalid characters.
4467
4468 *** The functions decode-coding-region and encode-coding-region remove
4469 text properties of the target region. Ideally, they should correctly
4470 preserve text properties, but for the moment, it's hard. Removing
4471 text properties is better than preserving them in a less-than-correct
4472 way.
4473
4474 *** prefer-coding-system sets EOL conversion of default coding systems.
4475 If the argument to prefer-coding-system specifies a certain type of
4476 end of line conversion, the default coding systems set by
4477 prefer-coding-system will specify that conversion type for end of line.
4478
4479 *** The new function thai-compose-string can be used to properly
4480 compose Thai characters in a string.
4481
4482 ** The primitive `define-prefix-command' now takes an optional third
4483 argument NAME, which should be a string. It supplies the menu name
4484 for the created keymap. Keymaps created in order to be displayed as
4485 menus should always use the third argument.
4486
4487 ** The meanings of optional second arguments for read-char,
4488 read-event, and read-char-exclusive are flipped. Now the second
4489 arguments are INHERIT-INPUT-METHOD. These functions use the current
4490 input method (if any) if and only if INHERIT-INPUT-METHOD is non-nil.
4491
4492 ** The new function clear-this-command-keys empties out the contents
4493 of the vector that (this-command-keys) returns. This is useful in
4494 programs that read passwords, to prevent the passwords from echoing
4495 inadvertently as part of the next command in certain cases.
4496
4497 ** The new macro `with-temp-message' displays a temporary message in
4498 the echo area, while executing some Lisp code. Like `progn', it
4499 returns the value of the last form, but it also restores the previous
4500 echo area contents.
4501
4502 (with-temp-message MESSAGE &rest BODY)
4503
4504 ** The function `require' now takes an optional third argument
4505 NOERROR. If it is non-nil, then there is no error if the
4506 requested feature cannot be loaded.
4507
4508 ** In the function modify-face, an argument of (nil) for the
4509 foreground color, background color or stipple pattern
4510 means to clear out that attribute.
4511
4512 ** The `outer-window-id' frame property of an X frame
4513 gives the window number of the outermost X window for the frame.
4514
4515 ** Temporary buffers made with with-output-to-temp-buffer are now
4516 read-only by default, and normally use the major mode Help mode
4517 unless you put them in some other non-Fundamental mode before the
4518 end of with-output-to-temp-buffer.
4519
4520 ** The new functions gap-position and gap-size return information on
4521 the gap of the current buffer.
4522
4523 ** The new functions position-bytes and byte-to-position provide a way
4524 to convert between character positions and byte positions in the
4525 current buffer.
4526
4527 ** vc.el defines two new macros, `edit-vc-file' and `with-vc-file', to
4528 facilitate working with version-controlled files from Lisp programs.
4529 These macros check out a given file automatically if needed, and check
4530 it back in after any modifications have been made.
4531 \f
4532 * Installation Changes in Emacs 20.3
4533
4534 ** The default value of load-path now includes most subdirectories of
4535 the site-specific directories /usr/local/share/emacs/site-lisp and
4536 /usr/local/share/emacs/VERSION/site-lisp, in addition to those
4537 directories themselves. Both immediate subdirectories and
4538 subdirectories multiple levels down are added to load-path.
4539
4540 Not all subdirectories are included, though. Subdirectories whose
4541 names do not start with a letter or digit are excluded.
4542 Subdirectories named RCS or CVS are excluded. Also, a subdirectory
4543 which contains a file named `.nosearch' is excluded. You can use
4544 these methods to prevent certain subdirectories from being searched.
4545
4546 Emacs finds these subdirectories and adds them to load-path when it
4547 starts up. While it would be cleaner to find the subdirectories each
4548 time Emacs loads a file, that would be much slower.
4549
4550 This feature is an incompatible change. If you have stored some Emacs
4551 Lisp files in a subdirectory of the site-lisp directory specifically
4552 to prevent them from being used, you will need to rename the
4553 subdirectory to start with a non-alphanumeric character, or create a
4554 `.nosearch' file in it, in order to continue to achieve the desired
4555 results.
4556
4557 ** Emacs no longer includes an old version of the C preprocessor from
4558 GCC. This was formerly used to help compile Emacs with C compilers
4559 that had limits on the significant length of an identifier, but in
4560 fact we stopped supporting such compilers some time ago.
4561 \f
4562 * Changes in Emacs 20.3
4563
4564 ** The new command C-x z (repeat) repeats the previous command
4565 including its argument. If you repeat the z afterward,
4566 it repeats the command additional times; thus, you can
4567 perform many repetitions with one keystroke per repetition.
4568
4569 ** Emacs now supports "selective undo" which undoes only within a
4570 specified region. To do this, set point and mark around the desired
4571 region and type C-u C-x u (or C-u C-_). You can then continue undoing
4572 further, within the same region, by repeating the ordinary undo
4573 command C-x u or C-_. This will keep undoing changes that were made
4574 within the region you originally specified, until either all of them
4575 are undone, or it encounters a change which crosses the edge of that
4576 region.
4577
4578 In Transient Mark mode, undoing when a region is active requests
4579 selective undo.
4580
4581 ** If you specify --unibyte when starting Emacs, then all buffers are
4582 unibyte, except when a Lisp program specifically creates a multibyte
4583 buffer. Setting the environment variable EMACS_UNIBYTE has the same
4584 effect. The --no-unibyte option overrides EMACS_UNIBYTE and directs
4585 Emacs to run normally in multibyte mode.
4586
4587 The option --unibyte does not affect the reading of Emacs Lisp files,
4588 though. If you want a Lisp file to be read in unibyte mode, use
4589 -*-unibyte: t;-*- on its first line. That will force Emacs to
4590 load that file in unibyte mode, regardless of how Emacs was started.
4591
4592 ** toggle-enable-multibyte-characters no longer has a key binding and
4593 no longer appears in the menu bar. We've realized that changing the
4594 enable-multibyte-characters variable in an existing buffer is
4595 something that most users not do.
4596
4597 ** You can specify a coding system to use for the next cut or paste
4598 operations through the window system with the command C-x RET X.
4599 The coding system can make a difference for communication with other
4600 applications.
4601
4602 C-x RET x specifies a coding system for all subsequent cutting and
4603 pasting operations.
4604
4605 ** You can specify the printer to use for commands that do printing by
4606 setting the variable `printer-name'. Just what a printer name looks
4607 like depends on your operating system. You can specify a different
4608 printer for the Postscript printing commands by setting
4609 `ps-printer-name'.
4610
4611 ** Emacs now supports on-the-fly spell checking by the means of a
4612 minor mode. It is called M-x flyspell-mode. You don't have to remember
4613 any other special commands to use it, and you will hardly notice it
4614 except when you make a spelling error. Flyspell works by highlighting
4615 incorrect words as soon as they are completed or as soon as the cursor
4616 hits a new word.
4617
4618 Flyspell mode works with whichever dictionary you have selected for
4619 Ispell in Emacs. In TeX mode, it understands TeX syntax so as not
4620 to be confused by TeX commands.
4621
4622 You can correct a misspelled word by editing it into something
4623 correct. You can also correct it, or accept it as correct, by
4624 clicking on the word with Mouse-2; that gives you a pop-up menu
4625 of various alternative replacements and actions.
4626
4627 Flyspell mode also proposes "automatic" corrections. M-TAB replaces
4628 the current misspelled word with a possible correction. If several
4629 corrections are made possible, M-TAB cycles through them in
4630 alphabetical order, or in order of decreasing likelihood if
4631 flyspell-sort-corrections is nil.
4632
4633 Flyspell mode also flags an error when a word is repeated, if
4634 flyspell-mark-duplications-flag is non-nil.
4635
4636 ** Changes in input method usage.
4637
4638 Now you can use arrow keys (right, left, down, up) for selecting among
4639 the alternatives just the same way as you do by C-f, C-b, C-n, and C-p
4640 respectively.
4641
4642 You can use the ENTER key to accept the current conversion.
4643
4644 If you type TAB to display a list of alternatives, you can select one
4645 of the alternatives with Mouse-2.
4646
4647 The meaning of the variable `input-method-verbose-flag' is changed so
4648 that you can set it to t, nil, `default', or `complex-only'.
4649
4650 If the value is nil, extra guidance is never given.
4651
4652 If the value is t, extra guidance is always given.
4653
4654 If the value is `complex-only', extra guidance is always given only
4655 when you are using complex input methods such as chinese-py.
4656
4657 If the value is `default' (this is the default), extra guidance is
4658 given in the following case:
4659 o When you are using a complex input method.
4660 o When you are using a simple input method but not in the minibuffer.
4661
4662 If you are using Emacs through a very slow line, setting
4663 input-method-verbose-flag to nil or to complex-only is a good choice,
4664 and if you are using an input method you are not familiar with,
4665 setting it to t is helpful.
4666
4667 The old command select-input-method is now called set-input-method.
4668
4669 In the language environment "Korean", you can use the following
4670 keys:
4671 Shift-SPC toggle-korean-input-method
4672 C-F9 quail-hangul-switch-symbol-ksc
4673 F9 quail-hangul-switch-hanja
4674 These key bindings are canceled when you switch to another language
4675 environment.
4676
4677 ** The minibuffer history of file names now records the specified file
4678 names, not the entire minibuffer input. For example, if the
4679 minibuffer starts out with /usr/foo/, you might type in /etc/passwd to
4680 get
4681
4682 /usr/foo//etc/passwd
4683
4684 which stands for the file /etc/passwd.
4685
4686 Formerly, this used to put /usr/foo//etc/passwd in the history list.
4687 Now this puts just /etc/passwd in the history list.
4688
4689 ** If you are root, Emacs sets backup-by-copying-when-mismatch to t
4690 at startup, so that saving a file will be sure to preserve
4691 its owner and group.
4692
4693 ** find-func.el can now also find the place of definition of Emacs
4694 Lisp variables in user-loaded libraries.
4695
4696 ** C-x r t (string-rectangle) now deletes the existing rectangle
4697 contents before inserting the specified string on each line.
4698
4699 ** There is a new command delete-whitespace-rectangle
4700 which deletes whitespace starting from a particular column
4701 in all the lines on a rectangle. The column is specified
4702 by the left edge of the rectangle.
4703
4704 ** You can now store a number into a register with C-u NUMBER C-x r n REG,
4705 increment it by INC with C-u INC C-x r + REG (to increment by one, omit
4706 C-u INC), and insert it in the buffer with C-x r g REG. This is useful
4707 for writing keyboard macros.
4708
4709 ** The new command M-x speedbar displays a frame in which directories,
4710 files, and tags can be displayed, manipulated, and jumped to. The
4711 frame defaults to 20 characters in width, and is the same height as
4712 the frame that it was started from. Some major modes define
4713 additional commands for the speedbar, including Rmail, GUD/GDB, and
4714 info.
4715
4716 ** query-replace-regexp is now bound to C-M-%.
4717
4718 ** In Transient Mark mode, when the region is active, M-x
4719 query-replace and the other replace commands now operate on the region
4720 contents only.
4721
4722 ** M-x write-region, when used interactively, now asks for
4723 confirmation before overwriting an existing file. When you call
4724 the function from a Lisp program, a new optional argument CONFIRM
4725 says whether to ask for confirmation in this case.
4726
4727 ** If you use find-file-literally and the file is already visited
4728 non-literally, the command asks you whether to revisit the file
4729 literally. If you say no, it signals an error.
4730
4731 ** Major modes defined with the "derived mode" feature
4732 now use the proper name for the mode hook: WHATEVER-mode-hook.
4733 Formerly they used the name WHATEVER-mode-hooks, but that is
4734 inconsistent with Emacs conventions.
4735
4736 ** shell-command-on-region (and shell-command) reports success or
4737 failure if the command produces no output.
4738
4739 ** Set focus-follows-mouse to nil if your window system or window
4740 manager does not transfer focus to another window when you just move
4741 the mouse.
4742
4743 ** mouse-menu-buffer-maxlen has been renamed to
4744 mouse-buffer-menu-maxlen to be consistent with the other related
4745 function and variable names.
4746
4747 ** The new variable auto-coding-alist specifies coding systems for
4748 reading specific files. This has higher priority than
4749 file-coding-system-alist.
4750
4751 ** If you set the variable unibyte-display-via-language-environment to
4752 t, then Emacs displays non-ASCII characters are displayed by
4753 converting them to the equivalent multibyte characters according to
4754 the current language environment. As a result, they are displayed
4755 according to the current fontset.
4756
4757 ** C-q's handling of codes in the range 0200 through 0377 is changed.
4758
4759 The codes in the range 0200 through 0237 are inserted as one byte of
4760 that code regardless of the values of nonascii-translation-table and
4761 nonascii-insert-offset.
4762
4763 For the codes in the range 0240 through 0377, if
4764 enable-multibyte-characters is non-nil and nonascii-translation-table
4765 nor nonascii-insert-offset can't convert them to valid multibyte
4766 characters, they are converted to Latin-1 characters.
4767
4768 ** If you try to find a file that is not read-accessible, you now get
4769 an error, rather than an empty buffer and a warning.
4770
4771 ** In the minibuffer history commands M-r and M-s, an upper case
4772 letter in the regular expression forces case-sensitive search.
4773
4774 ** In the *Help* buffer, cross-references to commands and variables
4775 are inferred and hyperlinked. Use C-h m in Help mode for the relevant
4776 command keys.
4777
4778 ** M-x apropos-command, with a prefix argument, no longer looks for
4779 user option variables--instead it looks for noninteractive functions.
4780
4781 Meanwhile, the command apropos-variable normally searches for
4782 user option variables; with a prefix argument, it looks at
4783 all variables that have documentation.
4784
4785 ** When you type a long line in the minibuffer, and the minibuffer
4786 shows just one line, automatically scrolling works in a special way
4787 that shows you overlap with the previous line of text. The variable
4788 minibuffer-scroll-overlap controls how many characters of overlap
4789 it should show; the default is 20.
4790
4791 Meanwhile, Resize Minibuffer mode is still available; in that mode,
4792 the minibuffer grows taller (up to a point) as needed to show the whole
4793 of your input.
4794
4795 ** The new command M-x customize-changed-options lets you customize
4796 all the options whose meanings or default values have changed in
4797 recent Emacs versions. You specify a previous Emacs version number as
4798 argument, and the command creates a customization buffer showing all
4799 the customizable options which were changed since that version.
4800 Newly added options are included as well.
4801
4802 If you don't specify a particular version number argument,
4803 then the customization buffer shows all the customizable options
4804 for which Emacs versions of changes are recorded.
4805
4806 This function is also bound to the Changed Options entry in the
4807 Customize menu.
4808
4809 ** When you run M-x grep with a prefix argument, it figures out
4810 the tag around point and puts that into the default grep command.
4811
4812 ** The new command M-* (pop-tag-mark) pops back through a history of
4813 buffer positions from which M-. or other tag-finding commands were
4814 invoked.
4815
4816 ** The new variable comment-padding specifies the number of spaces
4817 that `comment-region' will insert before the actual text of the comment.
4818 The default is 1.
4819
4820 ** In Fortran mode the characters `.', `_' and `$' now have symbol
4821 syntax, not word syntax. Fortran mode now supports `imenu' and has
4822 new commands fortran-join-line (M-^) and fortran-narrow-to-subprogram
4823 (C-x n d). M-q can be used to fill a statement or comment block
4824 sensibly.
4825
4826 ** GUD now supports jdb, the Java debugger, and pdb, the Python debugger.
4827
4828 ** If you set the variable add-log-keep-changes-together to a non-nil
4829 value, the command `C-x 4 a' will automatically notice when you make
4830 two entries in one day for one file, and combine them.
4831
4832 ** You can use the command M-x diary-mail-entries to mail yourself a
4833 reminder about upcoming diary entries. See the documentation string
4834 for a sample shell script for calling this function automatically
4835 every night.
4836
4837 ** Desktop changes
4838
4839 *** All you need to do to enable use of the Desktop package, is to set
4840 the variable desktop-enable to t with Custom.
4841
4842 *** Minor modes are now restored. Which minor modes are restored
4843 and how modes are restored is controlled by `desktop-minor-mode-table'.
4844
4845 ** There is no need to do anything special, now, to enable Gnus to
4846 read and post multi-lingual articles.
4847
4848 ** Outline mode has now support for showing hidden outlines when
4849 doing an isearch. In order for this to happen search-invisible should
4850 be set to open (the default). If an isearch match is inside a hidden
4851 outline the outline is made visible. If you continue pressing C-s and
4852 the match moves outside the formerly invisible outline, the outline is
4853 made invisible again.
4854
4855 ** Mail reading and sending changes
4856
4857 *** The Rmail e command now switches to displaying the whole header of
4858 the message before it lets you edit the message. This is so that any
4859 changes you make in the header will not be lost if you subsequently
4860 toggle.
4861
4862 *** The w command in Rmail, which writes the message body into a file,
4863 now works in the summary buffer as well. (The command to delete the
4864 summary buffer is now Q.) The default file name for the w command, if
4865 the message has no subject, is stored in the variable
4866 rmail-default-body-file.
4867
4868 *** Most of the commands and modes that operate on mail and netnews no
4869 longer depend on the value of mail-header-separator. Instead, they
4870 handle whatever separator the buffer happens to use.
4871
4872 *** If you set mail-signature to a value which is not t, nil, or a string,
4873 it should be an expression. When you send a message, this expression
4874 is evaluated to insert the signature.
4875
4876 *** The new Lisp library feedmail.el (version 8) enhances processing of
4877 outbound email messages. It works in coordination with other email
4878 handling packages (e.g., rmail, VM, gnus) and is responsible for
4879 putting final touches on messages and actually submitting them for
4880 transmission. Users of the emacs program "fakemail" might be
4881 especially interested in trying feedmail.
4882
4883 feedmail is not enabled by default. See comments at the top of
4884 feedmail.el for set-up instructions. Among the bigger features
4885 provided by feedmail are:
4886
4887 **** you can park outgoing messages into a disk-based queue and
4888 stimulate sending some or all of them later (handy for laptop users);
4889 there is also a queue for draft messages
4890
4891 **** you can get one last look at the prepped outbound message and
4892 be prompted for confirmation
4893
4894 **** does smart filling of address headers
4895
4896 **** can generate a MESSAGE-ID: line and a DATE: line; the date can be
4897 the time the message was written or the time it is being sent; this
4898 can make FCC copies more closely resemble copies that recipients get
4899
4900 **** you can specify an arbitrary function for actually transmitting
4901 the message; included in feedmail are interfaces for /bin/[r]mail,
4902 /usr/lib/sendmail, and elisp smtpmail; it's easy to write a new
4903 function for something else (10-20 lines of elisp)
4904
4905 ** Dired changes
4906
4907 *** The Dired function dired-do-toggle, which toggles marked and unmarked
4908 files, is now bound to "t" instead of "T".
4909
4910 *** dired-at-point has been added to ffap.el. It allows one to easily
4911 run Dired on the directory name at point.
4912
4913 *** Dired has a new command: %g. It searches the contents of
4914 files in the directory and marks each file that contains a match
4915 for a specified regexp.
4916
4917 ** VC Changes
4918
4919 *** New option vc-ignore-vc-files lets you turn off version control
4920 conveniently.
4921
4922 *** VC Dired has been completely rewritten. It is now much
4923 faster, especially for CVS, and works very similar to ordinary
4924 Dired.
4925
4926 VC Dired is invoked by typing C-x v d and entering the name of the
4927 directory to display. By default, VC Dired gives you a recursive
4928 listing of all files at or below the given directory which are
4929 currently locked (for CVS, all files not up-to-date are shown).
4930
4931 You can change the listing format by setting vc-dired-recurse to nil,
4932 then it shows only the given directory, and you may also set
4933 vc-dired-terse-display to nil, then it shows all files under version
4934 control plus the names of any subdirectories, so that you can type `i'
4935 on such lines to insert them manually, as in ordinary Dired.
4936
4937 All Dired commands operate normally in VC Dired, except for `v', which
4938 is redefined as the version control prefix. That means you may type
4939 `v l', `v =' etc. to invoke `vc-print-log', `vc-diff' and the like on
4940 the file named in the current Dired buffer line. `v v' invokes
4941 `vc-next-action' on this file, or on all files currently marked.
4942
4943 The new command `v t' (vc-dired-toggle-terse-mode) allows you to
4944 toggle between terse display (only locked files) and full display (all
4945 VC files plus subdirectories). There is also a special command,
4946 `* l', to mark all files currently locked.
4947
4948 Giving a prefix argument to C-x v d now does the same thing as in
4949 ordinary Dired: it allows you to supply additional options for the ls
4950 command in the minibuffer, to fine-tune VC Dired's output.
4951
4952 *** Under CVS, if you merge changes from the repository into a working
4953 file, and CVS detects conflicts, VC now offers to start an ediff
4954 session to resolve them.
4955
4956 Alternatively, you can use the new command `vc-resolve-conflicts' to
4957 resolve conflicts in a file at any time. It works in any buffer that
4958 contains conflict markers as generated by rcsmerge (which is what CVS
4959 uses as well).
4960
4961 *** You can now transfer changes between branches, using the new
4962 command vc-merge (C-x v m). It is implemented for RCS and CVS. When
4963 you invoke it in a buffer under version-control, you can specify
4964 either an entire branch or a pair of versions, and the changes on that
4965 branch or between the two versions are merged into the working file.
4966 If this results in any conflicts, they may be resolved interactively,
4967 using ediff.
4968
4969 ** Changes in Font Lock
4970
4971 *** The face and variable previously known as font-lock-reference-face
4972 are now called font-lock-constant-face to better reflect their typical
4973 use for highlighting constants and labels. (Its face properties are
4974 unchanged.) The variable font-lock-reference-face remains for now for
4975 compatibility reasons, but its value is font-lock-constant-face.
4976
4977 ** Frame name display changes
4978
4979 *** The command set-frame-name lets you set the name of the current
4980 frame. You can use the new command select-frame-by-name to select and
4981 raise a frame; this is mostly useful on character-only terminals, or
4982 when many frames are invisible or iconified.
4983
4984 *** On character-only terminal (not a window system), changing the
4985 frame name is now reflected on the mode line and in the Buffers/Frames
4986 menu.
4987
4988 ** Comint (subshell) changes
4989
4990 *** In Comint modes, the commands to kill, stop or interrupt a
4991 subjob now also kill pending input. This is for compatibility
4992 with ordinary shells, where the signal characters do this.
4993
4994 *** There are new commands in Comint mode.
4995
4996 C-c C-x fetches the "next" line from the input history;
4997 that is, the line after the last line you got.
4998 You can use this command to fetch successive lines, one by one.
4999
5000 C-c SPC accumulates lines of input. More precisely, it arranges to
5001 send the current line together with the following line, when you send
5002 the following line.
5003
5004 C-c C-a if repeated twice consecutively now moves to the process mark,
5005 which separates the pending input from the subprocess output and the
5006 previously sent input.
5007
5008 C-c M-r now runs comint-previous-matching-input-from-input;
5009 it searches for a previous command, using the current pending input
5010 as the search string.
5011
5012 *** New option compilation-scroll-output can be set to scroll
5013 automatically in compilation-mode windows.
5014
5015 ** C mode changes
5016
5017 *** Multiline macros are now handled, both as they affect indentation,
5018 and as recognized syntax. New syntactic symbol cpp-macro-cont is
5019 assigned to second and subsequent lines of a multiline macro
5020 definition.
5021
5022 *** A new style "user" which captures all non-hook-ified
5023 (i.e. top-level) .emacs file variable settings and customizations.
5024 Style "cc-mode" is an alias for "user" and is deprecated. "gnu"
5025 style is still the default however.
5026
5027 *** "java" style now conforms to Sun's JDK coding style.
5028
5029 *** There are new commands c-beginning-of-defun, c-end-of-defun which
5030 are alternatives which you could bind to C-M-a and C-M-e if you prefer
5031 them. They do not have key bindings by default.
5032
5033 *** New and improved implementations of M-a (c-beginning-of-statement)
5034 and M-e (c-end-of-statement).
5035
5036 *** C++ namespace blocks are supported, with new syntactic symbols
5037 namespace-open, namespace-close, and innamespace.
5038
5039 *** File local variable settings of c-file-style and c-file-offsets
5040 makes the style variables local to that buffer only.
5041
5042 *** New indentation functions c-lineup-close-paren,
5043 c-indent-one-line-block, c-lineup-dont-change.
5044
5045 *** Improvements (hopefully!) to the way CC Mode is loaded. You
5046 should now be able to do a (require 'cc-mode) to get the entire
5047 package loaded properly for customization in your .emacs file. A new
5048 variable c-initialize-on-load controls this and is t by default.
5049
5050 ** Changes to hippie-expand.
5051
5052 *** New customization variable `hippie-expand-dabbrev-skip-space'. If
5053 non-nil, trailing spaces may be included in the abbreviation to search for,
5054 which then gives the same behavior as the original `dabbrev-expand'.
5055
5056 *** New customization variable `hippie-expand-dabbrev-as-symbol'. If
5057 non-nil, characters of syntax '_' is considered part of the word when
5058 expanding dynamically.
5059
5060 *** New customization variable `hippie-expand-no-restriction'. If
5061 non-nil, narrowed buffers are widened before they are searched.
5062
5063 *** New customization variable `hippie-expand-only-buffers'. If
5064 non-empty, buffers searched are restricted to the types specified in
5065 this list. Useful for example when constructing new special-purpose
5066 expansion functions with `make-hippie-expand-function'.
5067
5068 *** Text properties of the expansion are no longer copied.
5069
5070 ** Changes in BibTeX mode.
5071
5072 *** Any titleword matching a regexp in the new variable
5073 bibtex-autokey-titleword-ignore (case sensitive) is ignored during
5074 automatic key generation. This replaces variable
5075 bibtex-autokey-titleword-first-ignore, which only checked for matches
5076 against the first word in the title.
5077
5078 *** Autokey generation now uses all words from the title, not just
5079 capitalized words. To avoid conflicts with existing customizations,
5080 bibtex-autokey-titleword-ignore is set up such that words starting with
5081 lowerkey characters will still be ignored. Thus, if you want to use
5082 lowercase words from the title, you will have to overwrite the
5083 bibtex-autokey-titleword-ignore standard setting.
5084
5085 *** Case conversion of names and title words for automatic key
5086 generation is more flexible. Variable bibtex-autokey-preserve-case is
5087 replaced by bibtex-autokey-titleword-case-convert and
5088 bibtex-autokey-name-case-convert.
5089
5090 ** Changes in vcursor.el.
5091
5092 *** Support for character terminals is available: there is a new keymap
5093 and the vcursor will appear as an arrow between buffer text. A
5094 variable `vcursor-interpret-input' allows input from the vcursor to be
5095 entered exactly as if typed. Numerous functions, including
5096 `vcursor-compare-windows', have been rewritten to improve consistency
5097 in the selection of windows and corresponding keymaps.
5098
5099 *** vcursor options can now be altered with M-x customize under the
5100 Editing group once the package is loaded.
5101
5102 *** Loading vcursor now does not define keys by default, as this is
5103 generally a bad side effect. Use M-x customize to set
5104 vcursor-key-bindings to t to restore the old behaviour.
5105
5106 *** vcursor-auto-disable can be `copy', which turns off copying from the
5107 vcursor, but doesn't disable it, after any non-vcursor command.
5108
5109 ** Ispell changes.
5110
5111 *** You can now spell check comments and strings in the current
5112 buffer with M-x ispell-comments-and-strings. Comments and strings
5113 are identified by syntax tables in effect.
5114
5115 *** Generic region skipping implemented.
5116 A single buffer can be broken into a number of regions where text will
5117 and will not be checked. The definitions of the regions can be user
5118 defined. New applications and improvements made available by this
5119 include:
5120
5121 o URLs are automatically skipped
5122 o EMail message checking is vastly improved.
5123
5124 *** Ispell can highlight the erroneous word even on non-window terminals.
5125
5126 ** Changes to RefTeX mode
5127
5128 RefTeX has been updated in order to make it more usable with very
5129 large projects (like a several volume math book). The parser has been
5130 re-written from scratch. To get maximum speed from RefTeX, check the
5131 section `Optimizations' in the manual.
5132
5133 *** New recursive parser.
5134
5135 The old version of RefTeX created a single large buffer containing the
5136 entire multifile document in order to parse the document. The new
5137 recursive parser scans the individual files.
5138
5139 *** Parsing only part of a document.
5140
5141 Reparsing of changed document parts can now be made faster by enabling
5142 partial scans. To use this feature, read the documentation string of
5143 the variable `reftex-enable-partial-scans' and set the variable to t.
5144
5145 (setq reftex-enable-partial-scans t)
5146
5147 *** Storing parsing information in a file.
5148
5149 This can improve startup times considerably. To turn it on, use
5150
5151 (setq reftex-save-parse-info t)
5152
5153 *** Using multiple selection buffers
5154
5155 If the creation of label selection buffers is too slow (this happens
5156 for large documents), you can reuse these buffers by setting
5157
5158 (setq reftex-use-multiple-selection-buffers t)
5159
5160 *** References to external documents.
5161
5162 The LaTeX package `xr' allows to cross-reference labels in external
5163 documents. RefTeX can provide information about the external
5164 documents as well. To use this feature, set up the \externaldocument
5165 macros required by the `xr' package and rescan the document with
5166 RefTeX. The external labels can then be accessed with the `x' key in
5167 the selection buffer provided by `reftex-reference' (bound to `C-c )').
5168 The `x' key also works in the table of contents buffer.
5169
5170 *** Many more labeled LaTeX environments are recognized by default.
5171
5172 The builtin command list now covers all the standard LaTeX commands,
5173 and all of the major packages included in the LaTeX distribution.
5174
5175 Also, RefTeX now understands the \appendix macro and changes
5176 the enumeration of sections in the *toc* buffer accordingly.
5177
5178 *** Mouse support for selection and *toc* buffers
5179
5180 The mouse can now be used to select items in the selection and *toc*
5181 buffers. See also the new option `reftex-highlight-selection'.
5182
5183 *** New keymaps for selection and table of contents modes.
5184
5185 The selection processes for labels and citation keys, and the table of
5186 contents buffer now have their own keymaps: `reftex-select-label-map',
5187 `reftex-select-bib-map', `reftex-toc-map'. The selection processes
5188 have a number of new keys predefined. In particular, TAB lets you
5189 enter a label with completion. Check the on-the-fly help (press `?'
5190 at the selection prompt) or read the Info documentation to find out
5191 more.
5192
5193 *** Support for the varioref package
5194
5195 The `v' key in the label selection buffer toggles \ref versus \vref.
5196
5197 *** New hooks
5198
5199 Three new hooks can be used to redefine the way labels, references,
5200 and citations are created. These hooks are
5201 `reftex-format-label-function', `reftex-format-ref-function',
5202 `reftex-format-cite-function'.
5203
5204 *** Citations outside LaTeX
5205
5206 The command `reftex-citation' may also be used outside LaTeX (e.g. in
5207 a mail buffer). See the Info documentation for details.
5208
5209 *** Short context is no longer fontified.
5210
5211 The short context in the label menu no longer copies the
5212 fontification from the text in the buffer. If you prefer it to be
5213 fontified, use
5214
5215 (setq reftex-refontify-context t)
5216
5217 ** file-cache-minibuffer-complete now accepts a prefix argument.
5218 With a prefix argument, it does not try to do completion of
5219 the file name within its directory; it only checks for other
5220 directories that contain the same file name.
5221
5222 Thus, given the file name Makefile, and assuming that a file
5223 Makefile.in exists in the same directory, ordinary
5224 file-cache-minibuffer-complete will try to complete Makefile to
5225 Makefile.in and will therefore never look for other directories that
5226 have Makefile. A prefix argument tells it not to look for longer
5227 names such as Makefile.in, so that instead it will look for other
5228 directories--just as if the name were already complete in its present
5229 directory.
5230
5231 ** New modes and packages
5232
5233 *** There is a new alternative major mode for Perl, Cperl mode.
5234 It has many more features than Perl mode, and some people prefer
5235 it, but some do not.
5236
5237 *** There is a new major mode, M-x vhdl-mode, for editing files of VHDL
5238 code.
5239
5240 *** M-x which-function-mode enables a minor mode that displays the
5241 current function name continuously in the mode line, as you move
5242 around in a buffer.
5243
5244 Which Function mode is effective in major modes which support Imenu.
5245
5246 *** Gametree is a major mode for editing game analysis trees. The author
5247 uses it for keeping notes about his postal Chess games, but it should
5248 be helpful for other two-player games as well, as long as they have an
5249 established system of notation similar to Chess.
5250
5251 *** The new minor mode checkdoc-minor-mode provides Emacs Lisp
5252 documentation string checking for style and spelling. The style
5253 guidelines are found in the Emacs Lisp programming manual.
5254
5255 *** The net-utils package makes some common networking features
5256 available in Emacs. Some of these functions are wrappers around
5257 system utilities (ping, nslookup, etc); others are implementations of
5258 simple protocols (finger, whois) in Emacs Lisp. There are also
5259 functions to make simple connections to TCP/IP ports for debugging and
5260 the like.
5261
5262 *** highlight-changes-mode is a minor mode that uses colors to
5263 identify recently changed parts of the buffer text.
5264
5265 *** The new package `midnight' lets you specify things to be done
5266 within Emacs at midnight--by default, kill buffers that you have not
5267 used in a considerable time. To use this feature, customize
5268 the user option `midnight-mode' to t.
5269
5270 *** The file generic-x.el defines a number of simple major modes.
5271
5272 apache-generic-mode: For Apache and NCSA httpd configuration files
5273 samba-generic-mode: Samba configuration files
5274 fvwm-generic-mode: For fvwm initialization files
5275 x-resource-generic-mode: For X resource files
5276 hosts-generic-mode: For hosts files (.rhosts, /etc/hosts, etc)
5277 mailagent-rules-generic-mode: For mailagent .rules files
5278 javascript-generic-mode: For JavaScript files
5279 vrml-generic-mode: For VRML files
5280 java-manifest-generic-mode: For Java MANIFEST files
5281 java-properties-generic-mode: For Java property files
5282 mailrc-generic-mode: For .mailrc files
5283
5284 Platform-specific modes:
5285
5286 prototype-generic-mode: For Solaris/Sys V prototype files
5287 pkginfo-generic-mode: For Solaris/Sys V pkginfo files
5288 alias-generic-mode: For C shell alias files
5289 inf-generic-mode: For MS-Windows INF files
5290 ini-generic-mode: For MS-Windows INI files
5291 reg-generic-mode: For MS-Windows Registry files
5292 bat-generic-mode: For MS-Windows BAT scripts
5293 rc-generic-mode: For MS-Windows Resource files
5294 rul-generic-mode: For InstallShield scripts
5295 \f
5296 * Lisp changes in Emacs 20.3 since the Emacs Lisp Manual was published
5297
5298 ** If you want a Lisp file to be read in unibyte mode,
5299 use -*-unibyte: t;-*- on its first line.
5300 That will force Emacs to read that file in unibyte mode.
5301 Otherwise, the file will be loaded and byte-compiled in multibyte mode.
5302
5303 Thus, each lisp file is read in a consistent way regardless of whether
5304 you started Emacs with --unibyte, so that a Lisp program gives
5305 consistent results regardless of how Emacs was started.
5306
5307 ** The new function assoc-default is useful for searching an alist,
5308 and using a default value if the key is not found there. You can
5309 specify a comparison predicate, so this function is useful for
5310 searching comparing a string against an alist of regular expressions.
5311
5312 ** The functions unibyte-char-to-multibyte and
5313 multibyte-char-to-unibyte convert between unibyte and multibyte
5314 character codes, in a way that is appropriate for the current language
5315 environment.
5316
5317 ** The functions read-event, read-char and read-char-exclusive now
5318 take two optional arguments. PROMPT, if non-nil, specifies a prompt
5319 string. SUPPRESS-INPUT-METHOD, if non-nil, says to disable the
5320 current input method for reading this one event.
5321
5322 ** Two new variables print-escape-nonascii and print-escape-multibyte
5323 now control whether to output certain characters as
5324 backslash-sequences. print-escape-nonascii applies to single-byte
5325 non-ASCII characters; print-escape-multibyte applies to multibyte
5326 characters. Both of these variables are used only when printing
5327 in readable fashion (prin1 uses them, princ does not).
5328 \f
5329 * Lisp changes in Emacs 20.3 before the Emacs Lisp Manual was published
5330
5331 ** Compiled Emacs Lisp files made with the modified "MBSK" version
5332 of Emacs 20.2 do not work in Emacs 20.3.
5333
5334 ** Buffer positions are now measured in characters, as they were
5335 in Emacs 19 and before. This means that (forward-char 1)
5336 always increases point by 1.
5337
5338 The function chars-in-region now just subtracts its arguments. It is
5339 considered obsolete. The function char-boundary-p has been deleted.
5340
5341 See below for additional changes relating to multibyte characters.
5342
5343 ** defcustom, defface and defgroup now accept the keyword `:version'.
5344 Use this to specify in which version of Emacs a certain variable's
5345 default value changed. For example,
5346
5347 (defcustom foo-max 34 "*Maximum number of foo's allowed."
5348 :type 'integer
5349 :group 'foo
5350 :version "20.3")
5351
5352 (defgroup foo-group nil "The foo group."
5353 :version "20.3")
5354
5355 If an entire new group is added or the variables in it have the
5356 default values changed, then just add a `:version' to that group. It
5357 is recommended that new packages added to the distribution contain a
5358 `:version' in the top level group.
5359
5360 This information is used to control the customize-changed-options command.
5361
5362 ** It is now an error to change the value of a symbol whose name
5363 starts with a colon--if it is interned in the standard obarray.
5364
5365 However, setting such a symbol to its proper value, which is that
5366 symbol itself, is not an error. This is for the sake of programs that
5367 support previous Emacs versions by explicitly setting these variables
5368 to themselves.
5369
5370 If you set the variable keyword-symbols-constant-flag to nil,
5371 this error is suppressed, and you can set these symbols to any
5372 values whatever.
5373
5374 ** There is a new debugger command, R.
5375 It evaluates an expression like e, but saves the result
5376 in the buffer *Debugger-record*.
5377
5378 ** Frame-local variables.
5379
5380 You can now make a variable local to various frames. To do this, call
5381 the function make-variable-frame-local; this enables frames to have
5382 local bindings for that variable.
5383
5384 These frame-local bindings are actually frame parameters: you create a
5385 frame-local binding in a specific frame by calling
5386 modify-frame-parameters and specifying the variable name as the
5387 parameter name.
5388
5389 Buffer-local bindings take precedence over frame-local bindings.
5390 Thus, if the current buffer has a buffer-local binding, that binding is
5391 active; otherwise, if the selected frame has a frame-local binding,
5392 that binding is active; otherwise, the default binding is active.
5393
5394 It would not be hard to implement window-local bindings, but it is not
5395 clear that this would be very useful; windows tend to come and go in a
5396 very transitory fashion, so that trying to produce any specific effect
5397 through a window-local binding would not be very robust.
5398
5399 ** `sregexq' and `sregex' are two new functions for constructing
5400 "symbolic regular expressions." These are Lisp expressions that, when
5401 evaluated, yield conventional string-based regexps. The symbolic form
5402 makes it easier to construct, read, and maintain complex patterns.
5403 See the documentation in sregex.el.
5404
5405 ** parse-partial-sexp's return value has an additional element which
5406 is used to pass information along if you pass it to another call to
5407 parse-partial-sexp, starting its scan where the first call ended.
5408 The contents of this field are not yet finalized.
5409
5410 ** eval-region now accepts a fourth optional argument READ-FUNCTION.
5411 If it is non-nil, that function is used instead of `read'.
5412
5413 ** unload-feature by default removes the feature's functions from
5414 known hooks to avoid trouble, but a package providing FEATURE can
5415 define a hook FEATURE-unload-hook to be run by unload-feature instead.
5416
5417 ** read-from-minibuffer no longer returns the argument DEFAULT-VALUE
5418 when the user enters empty input. It now returns the null string, as
5419 it did in Emacs 19. The default value is made available in the
5420 history via M-n, but it is not applied here as a default.
5421
5422 The other, more specialized minibuffer-reading functions continue to
5423 return the default value (not the null string) when the user enters
5424 empty input.
5425
5426 ** The new variable read-buffer-function controls which routine to use
5427 for selecting buffers. For example, if you set this variable to
5428 `iswitchb-read-buffer', iswitchb will be used to read buffer names.
5429 Other functions can also be used if they accept the same arguments as
5430 `read-buffer' and return the selected buffer name as a string.
5431
5432 ** The new function read-passwd reads a password from the terminal,
5433 echoing a period for each character typed. It takes three arguments:
5434 a prompt string, a flag which says "read it twice to make sure", and a
5435 default password to use if the user enters nothing.
5436
5437 ** The variable fill-nobreak-predicate gives major modes a way to
5438 specify not to break a line at certain places. Its value is a
5439 function which is called with no arguments, with point located at the
5440 place where a break is being considered. If the function returns
5441 non-nil, then the line won't be broken there.
5442
5443 ** window-end now takes an optional second argument, UPDATE.
5444 If this is non-nil, then the function always returns an accurate
5445 up-to-date value for the buffer position corresponding to the
5446 end of the window, even if this requires computation.
5447
5448 ** other-buffer now takes an optional argument FRAME
5449 which specifies which frame's buffer list to use.
5450 If it is nil, that means use the selected frame's buffer list.
5451
5452 ** The new variable buffer-display-time, always local in every buffer,
5453 holds the value of (current-time) as of the last time that a window
5454 was directed to display this buffer.
5455
5456 ** It is now meaningful to compare two window-configuration objects
5457 with `equal'. Two window-configuration objects are equal if they
5458 describe equivalent arrangements of windows, in the same frame--in
5459 other words, if they would give the same results if passed to
5460 set-window-configuration.
5461
5462 ** compare-window-configurations is a new function that compares two
5463 window configurations loosely. It ignores differences in saved buffer
5464 positions and scrolling, and considers only the structure and sizes of
5465 windows and the choice of buffers to display.
5466
5467 ** The variable minor-mode-overriding-map-alist allows major modes to
5468 override the key bindings of a minor mode. The elements of this alist
5469 look like the elements of minor-mode-map-alist: (VARIABLE . KEYMAP).
5470
5471 If the VARIABLE in an element of minor-mode-overriding-map-alist has a
5472 non-nil value, the paired KEYMAP is active, and totally overrides the
5473 map (if any) specified for the same variable in minor-mode-map-alist.
5474
5475 minor-mode-overriding-map-alist is automatically local in all buffers,
5476 and it is meant to be set by major modes.
5477
5478 ** The function match-string-no-properties is like match-string
5479 except that it discards all text properties from the result.
5480
5481 ** The function load-average now accepts an optional argument
5482 USE-FLOATS. If it is non-nil, the load average values are returned as
5483 floating point numbers, rather than as integers to be divided by 100.
5484
5485 ** The new variable temporary-file-directory specifies the directory
5486 to use for creating temporary files. The default value is determined
5487 in a reasonable way for your operating system; on GNU and Unix systems
5488 it is based on the TMP and TMPDIR environment variables.
5489
5490 ** Menu changes
5491
5492 *** easymenu.el now uses the new menu item format and supports the
5493 keywords :visible and :filter. The existing keyword :keys is now
5494 better supported.
5495
5496 The variable `easy-menu-precalculate-equivalent-keybindings' controls
5497 a new feature which calculates keyboard equivalents for the menu when
5498 you define the menu. The default is t. If you rarely use menus, you
5499 can set the variable to nil to disable this precalculation feature;
5500 then the calculation is done only if you use the menu bar.
5501
5502 *** A new format for menu items is supported.
5503
5504 In a keymap, a key binding that has the format
5505 (STRING . REAL-BINDING) or (STRING HELP-STRING . REAL-BINDING)
5506 defines a menu item. Now a menu item definition may also be a list that
5507 starts with the symbol `menu-item'.
5508
5509 The format is:
5510 (menu-item ITEM-NAME) or
5511 (menu-item ITEM-NAME REAL-BINDING . ITEM-PROPERTY-LIST)
5512 where ITEM-NAME is an expression which evaluates to the menu item
5513 string, and ITEM-PROPERTY-LIST has the form of a property list.
5514 The supported properties include
5515
5516 :enable FORM Evaluate FORM to determine whether the
5517 item is enabled.
5518 :visible FORM Evaluate FORM to determine whether the
5519 item should appear in the menu.
5520 :filter FILTER-FN
5521 FILTER-FN is a function of one argument,
5522 which will be REAL-BINDING.
5523 It should return a binding to use instead.
5524 :keys DESCRIPTION
5525 DESCRIPTION is a string that describes an equivalent keyboard
5526 binding for for REAL-BINDING. DESCRIPTION is expanded with
5527 `substitute-command-keys' before it is used.
5528 :key-sequence KEY-SEQUENCE
5529 KEY-SEQUENCE is a key-sequence for an equivalent
5530 keyboard binding.
5531 :key-sequence nil
5532 This means that the command normally has no
5533 keyboard equivalent.
5534 :help HELP HELP is the extra help string (not currently used).
5535 :button (TYPE . SELECTED)
5536 TYPE is :toggle or :radio.
5537 SELECTED is a form, to be evaluated, and its
5538 value says whether this button is currently selected.
5539
5540 Buttons are at the moment only simulated by prefixes in the menu.
5541 Eventually ordinary X-buttons may be supported.
5542
5543 (menu-item ITEM-NAME) defines unselectable item.
5544
5545 ** New event types
5546
5547 *** The new event type `mouse-wheel' is generated by a wheel on a
5548 mouse (such as the MS Intellimouse). The event contains a delta that
5549 corresponds to the amount and direction that the wheel is rotated,
5550 which is typically used to implement a scroll or zoom. The format is:
5551
5552 (mouse-wheel POSITION DELTA)
5553
5554 where POSITION is a list describing the position of the event in the
5555 same format as a mouse-click event, and DELTA is a signed number
5556 indicating the number of increments by which the wheel was rotated. A
5557 negative DELTA indicates that the wheel was rotated backwards, towards
5558 the user, and a positive DELTA indicates that the wheel was rotated
5559 forward, away from the user.
5560
5561 As of now, this event type is generated only on MS Windows.
5562
5563 *** The new event type `drag-n-drop' is generated when a group of
5564 files is selected in an application outside of Emacs, and then dragged
5565 and dropped onto an Emacs frame. The event contains a list of
5566 filenames that were dragged and dropped, which are then typically
5567 loaded into Emacs. The format is:
5568
5569 (drag-n-drop POSITION FILES)
5570
5571 where POSITION is a list describing the position of the event in the
5572 same format as a mouse-click event, and FILES is the list of filenames
5573 that were dragged and dropped.
5574
5575 As of now, this event type is generated only on MS Windows.
5576
5577 ** Changes relating to multibyte characters.
5578
5579 *** The variable enable-multibyte-characters is now read-only;
5580 any attempt to set it directly signals an error. The only way
5581 to change this value in an existing buffer is with set-buffer-multibyte.
5582
5583 *** In a string constant, `\ ' now stands for "nothing at all". You
5584 can use it to terminate a hex escape which is followed by a character
5585 that could otherwise be read as part of the hex escape.
5586
5587 *** String indices are now measured in characters, as they were
5588 in Emacs 19 and before.
5589
5590 The function chars-in-string has been deleted.
5591 The function concat-chars has been renamed to `string'.
5592
5593 *** The function set-buffer-multibyte sets the flag in the current
5594 buffer that says whether the buffer uses multibyte representation or
5595 unibyte representation. If the argument is nil, it selects unibyte
5596 representation. Otherwise it selects multibyte representation.
5597
5598 This function does not change the contents of the buffer, viewed
5599 as a sequence of bytes. However, it does change the contents
5600 viewed as characters; a sequence of two bytes which is treated as
5601 one character when the buffer uses multibyte representation
5602 will count as two characters using unibyte representation.
5603
5604 This function sets enable-multibyte-characters to record which
5605 representation is in use. It also adjusts various data in the buffer
5606 (including its markers, overlays and text properties) so that they are
5607 consistent with the new representation.
5608
5609 *** string-make-multibyte takes a string and converts it to multibyte
5610 representation. Most of the time, you don't need to care
5611 about the representation, because Emacs converts when necessary;
5612 however, it makes a difference when you compare strings.
5613
5614 The conversion of non-ASCII characters works by adding the value of
5615 nonascii-insert-offset to each character, or by translating them
5616 using the table nonascii-translation-table.
5617
5618 *** string-make-unibyte takes a string and converts it to unibyte
5619 representation. Most of the time, you don't need to care about the
5620 representation, but it makes a difference when you compare strings.
5621
5622 The conversion from multibyte to unibyte representation
5623 loses information; the only time Emacs performs it automatically
5624 is when inserting a multibyte string into a unibyte buffer.
5625
5626 *** string-as-multibyte takes a string, and returns another string
5627 which contains the same bytes, but treats them as multibyte.
5628
5629 *** string-as-unibyte takes a string, and returns another string
5630 which contains the same bytes, but treats them as unibyte.
5631
5632 *** The new function compare-strings lets you compare
5633 portions of two strings. Unibyte strings are converted to multibyte,
5634 so that a unibyte string can match a multibyte string.
5635 You can specify whether to ignore case or not.
5636
5637 *** assoc-ignore-case now uses compare-strings so that
5638 it can treat unibyte and multibyte strings as equal.
5639
5640 *** Regular expression operations and buffer string searches now
5641 convert the search pattern to multibyte or unibyte to accord with the
5642 buffer or string being searched.
5643
5644 One consequence is that you cannot always use \200-\377 inside of
5645 [...] to match all non-ASCII characters. This does still work when
5646 searching or matching a unibyte buffer or string, but not when
5647 searching or matching a multibyte string. Unfortunately, there is no
5648 obvious choice of syntax to use within [...] for that job. But, what
5649 you want is just to match all non-ASCII characters, the regular
5650 expression [^\0-\177] works for it.
5651
5652 *** Structure of coding system changed.
5653
5654 All coding systems (including aliases and subsidiaries) are named
5655 by symbols; the symbol's `coding-system' property is a vector
5656 which defines the coding system. Aliases share the same vector
5657 as the principal name, so that altering the contents of this
5658 vector affects the principal name and its aliases. You can define
5659 your own alias name of a coding system by the function
5660 define-coding-system-alias.
5661
5662 The coding system definition includes a property list of its own. Use
5663 the new functions `coding-system-get' and `coding-system-put' to
5664 access such coding system properties as post-read-conversion,
5665 pre-write-conversion, character-translation-table-for-decode,
5666 character-translation-table-for-encode, mime-charset, and
5667 safe-charsets. For instance, (coding-system-get 'iso-latin-1
5668 'mime-charset) gives the corresponding MIME-charset parameter
5669 `iso-8859-1'.
5670
5671 Among the coding system properties listed above, safe-charsets is new.
5672 The value of this property is a list of character sets which this
5673 coding system can correctly encode and decode. For instance:
5674 (coding-system-get 'iso-latin-1 'safe-charsets) => (ascii latin-iso8859-1)
5675
5676 Here, "correctly encode" means that the encoded character sets can
5677 also be handled safely by systems other than Emacs as far as they
5678 are capable of that coding system. Though, Emacs itself can encode
5679 the other character sets and read it back correctly.
5680
5681 *** The new function select-safe-coding-system can be used to find a
5682 proper coding system for encoding the specified region or string.
5683 This function requires a user interaction.
5684
5685 *** The new functions find-coding-systems-region and
5686 find-coding-systems-string are helper functions used by
5687 select-safe-coding-system. They return a list of all proper coding
5688 systems to encode a text in some region or string. If you don't want
5689 a user interaction, use one of these functions instead of
5690 select-safe-coding-system.
5691
5692 *** The explicit encoding and decoding functions, such as
5693 decode-coding-region and encode-coding-string, now set
5694 last-coding-system-used to reflect the actual way encoding or decoding
5695 was done.
5696
5697 *** The new function detect-coding-with-language-environment can be
5698 used to detect a coding system of text according to priorities of
5699 coding systems used by some specific language environment.
5700
5701 *** The functions detect-coding-region and detect-coding-string always
5702 return a list if the arg HIGHEST is nil. Thus, if only ASCII
5703 characters are found, they now return a list of single element
5704 `undecided' or its subsidiaries.
5705
5706 *** The new functions coding-system-change-eol-conversion and
5707 coding-system-change-text-conversion can be used to get a different
5708 coding system than what specified only in how end-of-line or text is
5709 converted.
5710
5711 *** The new function set-selection-coding-system can be used to set a
5712 coding system for communicating with other X clients.
5713
5714 *** The function `map-char-table' now passes as argument only valid
5715 character codes, plus generic characters that stand for entire
5716 character sets or entire subrows of a character set. In other words,
5717 each time `map-char-table' calls its FUNCTION argument, the key value
5718 either will be a valid individual character code, or will stand for a
5719 range of characters.
5720
5721 *** The new function `char-valid-p' can be used for checking whether a
5722 Lisp object is a valid character code or not.
5723
5724 *** The new function `charset-after' returns a charset of a character
5725 in the current buffer at position POS.
5726
5727 *** Input methods are now implemented using the variable
5728 input-method-function. If this is non-nil, its value should be a
5729 function; then, whenever Emacs reads an input event that is a printing
5730 character with no modifier bits, it calls that function, passing the
5731 event as an argument. Often this function will read more input, first
5732 binding input-method-function to nil.
5733
5734 The return value should be a list of the events resulting from input
5735 method processing. These events will be processed sequentially as
5736 input, before resorting to unread-command-events. Events returned by
5737 the input method function are not passed to the input method function,
5738 not even if they are printing characters with no modifier bits.
5739
5740 The input method function is not called when reading the second and
5741 subsequent events of a key sequence.
5742
5743 *** You can customize any language environment by using
5744 set-language-environment-hook and exit-language-environment-hook.
5745
5746 The hook `exit-language-environment-hook' should be used to undo
5747 customizations that you made with set-language-environment-hook. For
5748 instance, if you set up a special key binding for a specific language
5749 environment by set-language-environment-hook, you should set up
5750 exit-language-environment-hook to restore the normal key binding.
5751 \f
5752 * Changes in Emacs 20.1
5753
5754 ** Emacs has a new facility for customization of its many user
5755 options. It is called M-x customize. With this facility you can look
5756 at the many user options in an organized way; they are grouped into a
5757 tree structure.
5758
5759 M-x customize also knows what sorts of values are legitimate for each
5760 user option and ensures that you don't use invalid values.
5761
5762 With M-x customize, you can set options either for the present Emacs
5763 session or permanently. (Permanent settings are stored automatically
5764 in your .emacs file.)
5765
5766 ** Scroll bars are now on the left side of the window.
5767 You can change this with M-x customize-option scroll-bar-mode.
5768
5769 ** The mode line no longer includes the string `Emacs'.
5770 This makes more space in the mode line for other information.
5771
5772 ** When you select a region with the mouse, it is highlighted
5773 immediately afterward. At that time, if you type the DELETE key, it
5774 kills the region.
5775
5776 The BACKSPACE key, and the ASCII character DEL, do not do this; they
5777 delete the character before point, as usual.
5778
5779 ** In an incremental search the whole current match is highlighted
5780 on terminals which support this. (You can disable this feature
5781 by setting search-highlight to nil.)
5782
5783 ** In the minibuffer, in some cases, you can now use M-n to
5784 insert the default value into the minibuffer as text. In effect,
5785 the default value (if the minibuffer routines know it) is tacked
5786 onto the history "in the future". (The more normal use of the
5787 history list is to use M-p to insert minibuffer input used in the
5788 past.)
5789
5790 ** In Text mode, now only blank lines separate paragraphs.
5791 This makes it possible to get the full benefit of Adaptive Fill mode
5792 in Text mode, and other modes derived from it (such as Mail mode).
5793 TAB in Text mode now runs the command indent-relative; this
5794 makes a practical difference only when you use indented paragraphs.
5795
5796 As a result, the old Indented Text mode is now identical to Text mode,
5797 and is an alias for it.
5798
5799 If you want spaces at the beginning of a line to start a paragraph,
5800 use the new mode, Paragraph Indent Text mode.
5801
5802 ** Scrolling changes
5803
5804 *** Scroll commands to scroll a whole screen now preserve the screen
5805 position of the cursor, if scroll-preserve-screen-position is non-nil.
5806
5807 In this mode, if you scroll several screens back and forth, finishing
5808 on the same screen where you started, the cursor goes back to the line
5809 where it started.
5810
5811 *** If you set scroll-conservatively to a small number, then when you
5812 move point a short distance off the screen, Emacs will scroll the
5813 screen just far enough to bring point back on screen, provided that
5814 does not exceed `scroll-conservatively' lines.
5815
5816 *** The new variable scroll-margin says how close point can come to the
5817 top or bottom of a window. It is a number of screen lines; if point
5818 comes within that many lines of the top or bottom of the window, Emacs
5819 recenters the window.
5820
5821 ** International character set support (MULE)
5822
5823 Emacs now supports a wide variety of international character sets,
5824 including European variants of the Latin alphabet, as well as Chinese,
5825 Devanagari (Hindi and Marathi), Ethiopian, Greek, IPA, Japanese,
5826 Korean, Lao, Russian, Thai, Tibetan, and Vietnamese scripts. These
5827 features have been merged from the modified version of Emacs known as
5828 MULE (for "MULti-lingual Enhancement to GNU Emacs")
5829
5830 Users of these scripts have established many more-or-less standard
5831 coding systems for storing files. Emacs uses a single multibyte
5832 character encoding within Emacs buffers; it can translate from a wide
5833 variety of coding systems when reading a file and can translate back
5834 into any of these coding systems when saving a file.
5835
5836 Keyboards, even in the countries where these character sets are used,
5837 generally don't have keys for all the characters in them. So Emacs
5838 supports various "input methods", typically one for each script or
5839 language, to make it possible to type them.
5840
5841 The Emacs internal multibyte encoding represents a non-ASCII
5842 character as a sequence of bytes in the range 0200 through 0377.
5843
5844 The new prefix key C-x RET is used for commands that pertain
5845 to multibyte characters, coding systems, and input methods.
5846
5847 You can disable multibyte character support as follows:
5848
5849 (setq-default enable-multibyte-characters nil)
5850
5851 Calling the function standard-display-european turns off multibyte
5852 characters, unless you specify a non-nil value for the second
5853 argument, AUTO. This provides compatibility for people who are
5854 already using standard-display-european to continue using unibyte
5855 characters for their work until they want to change.
5856
5857 *** Input methods
5858
5859 An input method is a kind of character conversion which is designed
5860 specifically for interactive input. In Emacs, typically each language
5861 has its own input method (though sometimes several languages which use
5862 the same characters can share one input method). Some languages
5863 support several input methods.
5864
5865 The simplest kind of input method works by mapping ASCII letters into
5866 another alphabet. This is how the Greek and Russian input methods
5867 work.
5868
5869 A more powerful technique is composition: converting sequences of
5870 characters into one letter. Many European input methods use
5871 composition to produce a single non-ASCII letter from a sequence which
5872 consists of a letter followed by diacritics. For example, a' is one
5873 sequence of two characters that might be converted into a single
5874 letter.
5875
5876 The input methods for syllabic scripts typically use mapping followed
5877 by conversion. The input methods for Thai and Korean work this way.
5878 First, letters are mapped into symbols for particular sounds or tone
5879 marks; then, sequences of these which make up a whole syllable are
5880 mapped into one syllable sign--most often a "composite character".
5881
5882 None of these methods works very well for Chinese and Japanese, so
5883 they are handled specially. First you input a whole word using
5884 phonetic spelling; then, after the word is in the buffer, Emacs
5885 converts it into one or more characters using a large dictionary.
5886
5887 Since there is more than one way to represent a phonetically spelled
5888 word using Chinese characters, Emacs can only guess which one to use;
5889 typically these input methods give you a way to say "guess again" if
5890 the first guess is wrong.
5891
5892 *** The command C-x RET m (toggle-enable-multibyte-characters)
5893 turns multibyte character support on or off for the current buffer.
5894
5895 If multibyte character support is turned off in a buffer, then each
5896 byte is a single character, even codes 0200 through 0377--exactly as
5897 they did in Emacs 19.34. This includes the features for support for
5898 the European characters, ISO Latin-1 and ISO Latin-2.
5899
5900 However, there is no need to turn off multibyte character support to
5901 use ISO Latin-1 or ISO Latin-2; the Emacs multibyte character set
5902 includes all the characters in these character sets, and Emacs can
5903 translate automatically to and from either one.
5904
5905 *** Visiting a file in unibyte mode.
5906
5907 Turning off multibyte character support in the buffer after visiting a
5908 file with multibyte code conversion will display the multibyte
5909 sequences already in the buffer, byte by byte. This is probably not
5910 what you want.
5911
5912 If you want to edit a file of unibyte characters (Latin-1, for
5913 example), you can do it by specifying `no-conversion' as the coding
5914 system when reading the file. This coding system also turns off
5915 multibyte characters in that buffer.
5916
5917 If you turn off multibyte character support entirely, this turns off
5918 character conversion as well.
5919
5920 *** Displaying international characters on X Windows.
5921
5922 A font for X typically displays just one alphabet or script.
5923 Therefore, displaying the entire range of characters Emacs supports
5924 requires using many fonts.
5925
5926 Therefore, Emacs now supports "fontsets". Each fontset is a
5927 collection of fonts, each assigned to a range of character codes.
5928
5929 A fontset has a name, like a font. Individual fonts are defined by
5930 the X server; fontsets are defined within Emacs itself. But once you
5931 have defined a fontset, you can use it in a face or a frame just as
5932 you would use a font.
5933
5934 If a fontset specifies no font for a certain character, or if it
5935 specifies a font that does not exist on your system, then it cannot
5936 display that character. It will display an empty box instead.
5937
5938 The fontset height and width are determined by the ASCII characters
5939 (that is, by the font in the fontset which is used for ASCII
5940 characters). If another font in the fontset has a different height,
5941 or the wrong width, then characters assigned to that font are clipped,
5942 and displayed within a box if highlight-wrong-size-font is non-nil.
5943
5944 *** Defining fontsets.
5945
5946 Emacs does not use any fontset by default. Its default font is still
5947 chosen as in previous versions. You can tell Emacs to use a fontset
5948 with the `-fn' option or the `Font' X resource.
5949
5950 Emacs creates a standard fontset automatically according to the value
5951 of standard-fontset-spec. This fontset's short name is
5952 `fontset-standard'. Bold, italic, and bold-italic variants of the
5953 standard fontset are created automatically.
5954
5955 If you specify a default ASCII font with the `Font' resource or `-fn'
5956 argument, a fontset is generated from it. This works by replacing the
5957 FOUNDARY, FAMILY, ADD_STYLE, and AVERAGE_WIDTH fields of the font name
5958 with `*' then using this to specify a fontset. This fontset's short
5959 name is `fontset-startup'.
5960
5961 Emacs checks resources of the form Fontset-N where N is 0, 1, 2...
5962 The resource value should have this form:
5963 FONTSET-NAME, [CHARSET-NAME:FONT-NAME]...
5964 FONTSET-NAME should have the form of a standard X font name, except:
5965 * most fields should be just the wild card "*".
5966 * the CHARSET_REGISTRY field should be "fontset"
5967 * the CHARSET_ENCODING field can be any nickname of the fontset.
5968 The construct CHARSET-NAME:FONT-NAME can be repeated any number
5969 of times; each time specifies the font for one character set.
5970 CHARSET-NAME should be the name name of a character set, and
5971 FONT-NAME should specify an actual font to use for that character set.
5972
5973 Each of these fontsets has an alias which is made from the
5974 last two font name fields, CHARSET_REGISTRY and CHARSET_ENCODING.
5975 You can refer to the fontset by that alias or by its full name.
5976
5977 For any character sets that you don't mention, Emacs tries to choose a
5978 font by substituting into FONTSET-NAME. For instance, with the
5979 following resource,
5980 Emacs*Fontset-0: -*-fixed-medium-r-normal-*-24-*-*-*-*-*-fontset-24
5981 the font for ASCII is generated as below:
5982 -*-fixed-medium-r-normal-*-24-*-ISO8859-1
5983 Here is the substitution rule:
5984 Change CHARSET_REGISTRY and CHARSET_ENCODING to that of the charset
5985 defined in the variable x-charset-registries. For instance, ASCII has
5986 the entry (ascii . "ISO8859-1") in this variable. Then, reduce
5987 sequences of wild cards -*-...-*- with a single wildcard -*-.
5988 (This is to prevent use of auto-scaled fonts.)
5989
5990 The function which processes the fontset resource value to create the
5991 fontset is called create-fontset-from-fontset-spec. You can also call
5992 that function explicitly to create a fontset.
5993
5994 With the X resource Emacs.Font, you can specify a fontset name just
5995 like an actual font name. But be careful not to specify a fontset
5996 name in a wildcard resource like Emacs*Font--that tries to specify the
5997 fontset for other purposes including menus, and they cannot handle
5998 fontsets.
5999
6000 *** The command M-x set-language-environment sets certain global Emacs
6001 defaults for a particular choice of language.
6002
6003 Selecting a language environment typically specifies a default input
6004 method and which coding systems to recognize automatically when
6005 visiting files. However, it does not try to reread files you have
6006 already visited; the text in those buffers is not affected. The
6007 language environment may also specify a default choice of coding
6008 system for new files that you create.
6009
6010 It makes no difference which buffer is current when you use
6011 set-language-environment, because these defaults apply globally to the
6012 whole Emacs session.
6013
6014 For example, M-x set-language-environment RET Latin-1 RET
6015 chooses the Latin-1 character set. In the .emacs file, you can do this
6016 with (set-language-environment "Latin-1").
6017
6018 *** The command C-x RET f (set-buffer-file-coding-system)
6019 specifies the file coding system for the current buffer. This
6020 specifies what sort of character code translation to do when saving
6021 the file. As an argument, you must specify the name of one of the
6022 coding systems that Emacs supports.
6023
6024 *** The command C-x RET c (universal-coding-system-argument)
6025 lets you specify a coding system when you read or write a file.
6026 This command uses the minibuffer to read a coding system name.
6027 After you exit the minibuffer, the specified coding system
6028 is used for *the immediately following command*.
6029
6030 So if the immediately following command is a command to read or
6031 write a file, it uses the specified coding system for that file.
6032
6033 If the immediately following command does not use the coding system,
6034 then C-x RET c ultimately has no effect.
6035
6036 For example, C-x RET c iso-8859-1 RET C-x C-f temp RET
6037 visits the file `temp' treating it as ISO Latin-1.
6038
6039 *** You can specify the coding system for a file using the -*-
6040 construct. Include `coding: CODINGSYSTEM;' inside the -*-...-*-
6041 to specify use of coding system CODINGSYSTEM. You can also
6042 specify the coding system in a local variable list at the end
6043 of the file.
6044
6045 *** The command C-x RET t (set-terminal-coding-system) specifies
6046 the coding system for terminal output. If you specify a character
6047 code for terminal output, all characters output to the terminal are
6048 translated into that character code.
6049
6050 This feature is useful for certain character-only terminals built in
6051 various countries to support the languages of those countries.
6052
6053 By default, output to the terminal is not translated at all.
6054
6055 *** The command C-x RET k (set-keyboard-coding-system) specifies
6056 the coding system for keyboard input.
6057
6058 Character code translation of keyboard input is useful for terminals
6059 with keys that send non-ASCII graphic characters--for example,
6060 some terminals designed for ISO Latin-1 or subsets of it.
6061
6062 By default, keyboard input is not translated at all.
6063
6064 Character code translation of keyboard input is similar to using an
6065 input method, in that both define sequences of keyboard input that
6066 translate into single characters. However, input methods are designed
6067 to be convenient for interactive use, while the code translations are
6068 designed to work with terminals.
6069
6070 *** The command C-x RET p (set-buffer-process-coding-system)
6071 specifies the coding system for input and output to a subprocess.
6072 This command applies to the current buffer; normally, each subprocess
6073 has its own buffer, and thus you can use this command to specify
6074 translation to and from a particular subprocess by giving the command
6075 in the corresponding buffer.
6076
6077 By default, process input and output are not translated at all.
6078
6079 *** The variable file-name-coding-system specifies the coding system
6080 to use for encoding file names before operating on them.
6081 It is also used for decoding file names obtained from the system.
6082
6083 *** The command C-\ (toggle-input-method) activates or deactivates
6084 an input method. If no input method has been selected before, the
6085 command prompts for you to specify the language and input method you
6086 want to use.
6087
6088 C-u C-\ (select-input-method) lets you switch to a different input
6089 method. C-h C-\ (or C-h I) describes the current input method.
6090
6091 *** Some input methods remap the keyboard to emulate various keyboard
6092 layouts commonly used for particular scripts. How to do this
6093 remapping properly depends on your actual keyboard layout. To specify
6094 which layout your keyboard has, use M-x quail-set-keyboard-layout.
6095
6096 *** The command C-h C (describe-coding-system) displays
6097 the coding systems currently selected for various purposes, plus
6098 related information.
6099
6100 *** The command C-h h (view-hello-file) displays a file called
6101 HELLO, which has examples of text in many languages, using various
6102 scripts.
6103
6104 *** The command C-h L (describe-language-support) displays
6105 information about the support for a particular language.
6106 You specify the language as an argument.
6107
6108 *** The mode line now contains a letter or character that identifies
6109 the coding system used in the visited file. It normally follows the
6110 first dash.
6111
6112 A dash indicates the default state of affairs: no code conversion
6113 (except CRLF => newline if appropriate). `=' means no conversion
6114 whatsoever. The ISO 8859 coding systems are represented by digits
6115 1 through 9. Other coding systems are represented by letters:
6116
6117 A alternativnyj (Russian)
6118 B big5 (Chinese)
6119 C cn-gb-2312 (Chinese)
6120 C iso-2022-cn (Chinese)
6121 D in-is13194-devanagari (Indian languages)
6122 E euc-japan (Japanese)
6123 I iso-2022-cjk or iso-2022-ss2 (Chinese, Japanese, Korean)
6124 J junet (iso-2022-7) or old-jis (iso-2022-jp-1978-irv) (Japanese)
6125 K euc-korea (Korean)
6126 R koi8 (Russian)
6127 Q tibetan
6128 S shift_jis (Japanese)
6129 T lao
6130 T tis620 (Thai)
6131 V viscii or vscii (Vietnamese)
6132 i iso-2022-lock (Chinese, Japanese, Korean)
6133 k iso-2022-kr (Korean)
6134 v viqr (Vietnamese)
6135 z hz (Chinese)
6136
6137 When you are using a character-only terminal (not a window system),
6138 two additional characters appear in between the dash and the file
6139 coding system. These two characters describe the coding system for
6140 keyboard input, and the coding system for terminal output.
6141
6142 *** The new variable rmail-file-coding-system specifies the code
6143 conversion to use for RMAIL files. The default value is nil.
6144
6145 When you read mail with Rmail, each message is decoded automatically
6146 into Emacs' internal format. This has nothing to do with
6147 rmail-file-coding-system. That variable controls reading and writing
6148 Rmail files themselves.
6149
6150 *** The new variable sendmail-coding-system specifies the code
6151 conversion for outgoing mail. The default value is nil.
6152
6153 Actually, there are three different ways of specifying the coding system
6154 for sending mail:
6155
6156 - If you use C-x RET f in the mail buffer, that takes priority.
6157 - Otherwise, if you set sendmail-coding-system non-nil, that specifies it.
6158 - Otherwise, the default coding system for new files is used,
6159 if that is non-nil. That comes from your language environment.
6160 - Otherwise, Latin-1 is used.
6161
6162 *** The command C-h t (help-with-tutorial) accepts a prefix argument
6163 to specify the language for the tutorial file. Currently, English,
6164 Japanese, Korean and Thai are supported. We welcome additional
6165 translations.
6166
6167 ** An easy new way to visit a file with no code or format conversion
6168 of any kind: Use M-x find-file-literally. There is also a command
6169 insert-file-literally which inserts a file into the current buffer
6170 without any conversion.
6171
6172 ** C-q's handling of octal character codes is changed.
6173 You can now specify any number of octal digits.
6174 RET terminates the digits and is discarded;
6175 any other non-digit terminates the digits and is then used as input.
6176
6177 ** There are new commands for looking up Info documentation for
6178 functions, variables and file names used in your programs.
6179
6180 Type M-x info-lookup-symbol to look up a symbol in the buffer at point.
6181 Type M-x info-lookup-file to look up a file in the buffer at point.
6182
6183 Precisely which Info files are used to look it up depends on the major
6184 mode. For example, in C mode, the GNU libc manual is used.
6185
6186 ** M-TAB in most programming language modes now runs the command
6187 complete-symbol. This command performs completion on the symbol name
6188 in the buffer before point.
6189
6190 With a numeric argument, it performs completion based on the set of
6191 symbols documented in the Info files for the programming language that
6192 you are using.
6193
6194 With no argument, it does completion based on the current tags tables,
6195 just like the old binding of M-TAB (complete-tag).
6196
6197 ** File locking works with NFS now.
6198
6199 The lock file for FILENAME is now a symbolic link named .#FILENAME,
6200 in the same directory as FILENAME.
6201
6202 This means that collision detection between two different machines now
6203 works reasonably well; it also means that no file server or directory
6204 can become a bottleneck.
6205
6206 The new method does have drawbacks. It means that collision detection
6207 does not operate when you edit a file in a directory where you cannot
6208 create new files. Collision detection also doesn't operate when the
6209 file server does not support symbolic links. But these conditions are
6210 rare, and the ability to have collision detection while using NFS is
6211 so useful that the change is worth while.
6212
6213 When Emacs or a system crashes, this may leave behind lock files which
6214 are stale. So you may occasionally get warnings about spurious
6215 collisions. When you determine that the collision is spurious, just
6216 tell Emacs to go ahead anyway.
6217
6218 ** If you wish to use Show Paren mode to display matching parentheses,
6219 it is no longer sufficient to load paren.el. Instead you must call
6220 show-paren-mode.
6221
6222 ** If you wish to use Delete Selection mode to replace a highlighted
6223 selection when you insert new text, it is no longer sufficient to load
6224 delsel.el. Instead you must call the function delete-selection-mode.
6225
6226 ** If you wish to use Partial Completion mode to complete partial words
6227 within symbols or filenames, it is no longer sufficient to load
6228 complete.el. Instead you must call the function partial-completion-mode.
6229
6230 ** If you wish to use uniquify to rename buffers for you,
6231 it is no longer sufficient to load uniquify.el. You must also
6232 set uniquify-buffer-name-style to one of the non-nil legitimate values.
6233
6234 ** Changes in View mode.
6235
6236 *** Several new commands are available in View mode.
6237 Do H in view mode for a list of commands.
6238
6239 *** There are two new commands for entering View mode:
6240 view-file-other-frame and view-buffer-other-frame.
6241
6242 *** Exiting View mode does a better job of restoring windows to their
6243 previous state.
6244
6245 *** New customization variable view-scroll-auto-exit. If non-nil,
6246 scrolling past end of buffer makes view mode exit.
6247
6248 *** New customization variable view-exits-all-viewing-windows. If
6249 non-nil, view-mode will at exit restore all windows viewing buffer,
6250 not just the selected window.
6251
6252 *** New customization variable view-read-only. If non-nil, visiting a
6253 read-only file automatically enters View mode, and toggle-read-only
6254 turns View mode on or off.
6255
6256 *** New customization variable view-remove-frame-by-deleting controls
6257 how to remove a not needed frame at view mode exit. If non-nil,
6258 delete the frame, if nil make an icon of it.
6259
6260 ** C-x v l, the command to print a file's version control log,
6261 now positions point at the entry for the file's current branch version.
6262
6263 ** C-x v =, the command to compare a file with the last checked-in version,
6264 has a new feature. If the file is currently not locked, so that it is
6265 presumably identical to the last checked-in version, the command now asks
6266 which version to compare with.
6267
6268 ** When using hideshow.el, incremental search can temporarily show hidden
6269 blocks if a match is inside the block.
6270
6271 The block is hidden again if the search is continued and the next match
6272 is outside the block. By customizing the variable
6273 isearch-hide-immediately you can choose to hide all the temporarily
6274 shown blocks only when exiting from incremental search.
6275
6276 By customizing the variable hs-isearch-open you can choose what kind
6277 of blocks to temporarily show during isearch: comment blocks, code
6278 blocks, all of them or none.
6279
6280 ** The new command C-x 4 0 (kill-buffer-and-window) kills the
6281 current buffer and deletes the selected window. It asks for
6282 confirmation first.
6283
6284 ** C-x C-w, which saves the buffer into a specified file name,
6285 now changes the major mode according to that file name.
6286 However, the mode will not be changed if
6287 (1) a local variables list or the `-*-' line specifies a major mode, or
6288 (2) the current major mode is a "special" mode,
6289 not suitable for ordinary files, or
6290 (3) the new file name does not particularly specify any mode.
6291
6292 This applies to M-x set-visited-file-name as well.
6293
6294 However, if you set change-major-mode-with-file-name to nil, then
6295 these commands do not change the major mode.
6296
6297 ** M-x occur changes.
6298
6299 *** If the argument to M-x occur contains upper case letters,
6300 it performs a case-sensitive search.
6301
6302 *** In the *Occur* buffer made by M-x occur,
6303 if you type g or M-x revert-buffer, this repeats the search
6304 using the same regular expression and the same buffer as before.
6305
6306 ** In Transient Mark mode, the region in any one buffer is highlighted
6307 in just one window at a time. At first, it is highlighted in the
6308 window where you set the mark. The buffer's highlighting remains in
6309 that window unless you select to another window which shows the same
6310 buffer--then the highlighting moves to that window.
6311
6312 ** The feature to suggest key bindings when you use M-x now operates
6313 after the command finishes. The message suggesting key bindings
6314 appears temporarily in the echo area. The previous echo area contents
6315 come back after a few seconds, in case they contain useful information.
6316
6317 ** Each frame now independently records the order for recently
6318 selected buffers, so that the default for C-x b is now based on the
6319 buffers recently selected in the selected frame.
6320
6321 ** Outline mode changes.
6322
6323 *** Outline mode now uses overlays (this is the former noutline.el).
6324
6325 *** Incremental searches skip over invisible text in Outline mode.
6326
6327 ** When a minibuffer window is active but not the selected window, if
6328 you try to use the minibuffer, you used to get a nested minibuffer.
6329 Now, this not only gives an error, it also cancels the minibuffer that
6330 was already active.
6331
6332 The motive for this change is so that beginning users do not
6333 unknowingly move away from minibuffers, leaving them active, and then
6334 get confused by it.
6335
6336 If you want to be able to have recursive minibuffers, you must
6337 set enable-recursive-minibuffers to non-nil.
6338
6339 ** Changes in dynamic abbrevs.
6340
6341 *** Expanding dynamic abbrevs with M-/ is now smarter about case
6342 conversion. If the expansion has mixed case not counting the first
6343 character, and the abbreviation matches the beginning of the expansion
6344 including case, then the expansion is copied verbatim.
6345
6346 The expansion is also copied verbatim if the abbreviation itself has
6347 mixed case. And using SPC M-/ to copy an additional word always
6348 copies it verbatim except when the previous copied word is all caps.
6349
6350 *** The values of `dabbrev-case-replace' and `dabbrev-case-fold-search'
6351 are no longer Lisp expressions. They have simply three possible
6352 values.
6353
6354 `dabbrev-case-replace' has these three values: nil (don't preserve
6355 case), t (do), or `case-replace' (do like M-x query-replace).
6356 `dabbrev-case-fold-search' has these three values: nil (don't ignore
6357 case), t (do), or `case-fold-search' (do like search).
6358
6359 ** Minibuffer history lists are truncated automatically now to a
6360 certain length. The variable history-length specifies how long they
6361 can be. The default value is 30.
6362
6363 ** Changes in Mail mode.
6364
6365 *** The key C-x m no longer runs the `mail' command directly.
6366 Instead, it runs the command `compose-mail', which invokes the mail
6367 composition mechanism you have selected with the variable
6368 `mail-user-agent'. The default choice of user agent is
6369 `sendmail-user-agent', which gives behavior compatible with the old
6370 behavior.
6371
6372 C-x 4 m now runs compose-mail-other-window, and C-x 5 m runs
6373 compose-mail-other-frame.
6374
6375 *** While composing a reply to a mail message, from Rmail, you can use
6376 the command C-c C-r to cite just the region from the message you are
6377 replying to. This copies the text which is the selected region in the
6378 buffer that shows the original message.
6379
6380 *** The command C-c C-i inserts a file at the end of the message,
6381 with separator lines around the contents.
6382
6383 *** The command M-x expand-mail-aliases expands all mail aliases
6384 in suitable mail headers. Emacs automatically extracts mail alias
6385 definitions from your mail alias file (e.g., ~/.mailrc). You do not
6386 need to expand mail aliases yourself before sending mail.
6387
6388 *** New features in the mail-complete command.
6389
6390 **** The mail-complete command now inserts the user's full name,
6391 for local users or if that is known. The variable mail-complete-style
6392 controls the style to use, and whether to do this at all.
6393 Its values are like those of mail-from-style.
6394
6395 **** The variable mail-passwd-command lets you specify a shell command
6396 to run to fetch a set of password-entries that add to the ones in
6397 /etc/passwd.
6398
6399 **** The variable mail-passwd-file now specifies a list of files to read
6400 to get the list of user ids. By default, one file is used:
6401 /etc/passwd.
6402
6403 ** You can "quote" a file name to inhibit special significance of
6404 special syntax, by adding `/:' to the beginning. Thus, if you have a
6405 directory named `/foo:', you can prevent it from being treated as a
6406 reference to a remote host named `foo' by writing it as `/:/foo:'.
6407
6408 Emacs uses this new construct automatically when necessary, such as
6409 when you start it with a working directory whose name might otherwise
6410 be taken to be magic.
6411
6412 ** There is a new command M-x grep-find which uses find to select
6413 files to search through, and grep to scan them. The output is
6414 available in a Compile mode buffer, as with M-x grep.
6415
6416 M-x grep now uses the -e option if the grep program supports that.
6417 (-e prevents problems if the search pattern starts with a dash.)
6418
6419 ** In Dired, the & command now flags for deletion the files whose names
6420 suggest they are probably not needed in the long run.
6421
6422 In Dired, * is now a prefix key for mark-related commands.
6423
6424 new key dired.el binding old key
6425 ------- ---------------- -------
6426 * c dired-change-marks c
6427 * m dired-mark m
6428 * * dired-mark-executables * (binding deleted)
6429 * / dired-mark-directories / (binding deleted)
6430 * @ dired-mark-symlinks @ (binding deleted)
6431 * u dired-unmark u
6432 * DEL dired-unmark-backward DEL
6433 * ? dired-unmark-all-files M-C-?
6434 * ! dired-unmark-all-marks
6435 * % dired-mark-files-regexp % m
6436 * C-n dired-next-marked-file M-}
6437 * C-p dired-prev-marked-file M-{
6438
6439 ** Rmail changes.
6440
6441 *** When Rmail cannot convert your incoming mail into Babyl format, it
6442 saves the new mail in the file RMAILOSE.n, where n is an integer
6443 chosen to make a unique name. This way, Rmail will not keep crashing
6444 each time you run it.
6445
6446 *** In Rmail, the variable rmail-summary-line-count-flag now controls
6447 whether to include the line count in the summary. Non-nil means yes.
6448
6449 *** In Rmail summary buffers, d and C-d (the commands to delete
6450 messages) now take repeat counts as arguments. A negative argument
6451 means to move in the opposite direction.
6452
6453 *** In Rmail, the t command now takes an optional argument which lets
6454 you specify whether to show the message headers in full or pruned.
6455
6456 *** In Rmail, the new command w (rmail-output-body-to-file) writes
6457 just the body of the current message into a file, without the headers.
6458 It takes the file name from the message subject, by default, but you
6459 can edit that file name in the minibuffer before it is actually used
6460 for output.
6461
6462 ** Gnus changes.
6463
6464 *** nntp.el has been totally rewritten in an asynchronous fashion.
6465
6466 *** Article prefetching functionality has been moved up into
6467 Gnus.
6468
6469 *** Scoring can now be performed with logical operators like
6470 `and', `or', `not', and parent redirection.
6471
6472 *** Article washing status can be displayed in the
6473 article mode line.
6474
6475 *** gnus.el has been split into many smaller files.
6476
6477 *** Suppression of duplicate articles based on Message-ID.
6478
6479 (setq gnus-suppress-duplicates t)
6480
6481 *** New variables for specifying what score and adapt files
6482 are to be considered home score and adapt files. See
6483 `gnus-home-score-file' and `gnus-home-adapt-files'.
6484
6485 *** Groups can inherit group parameters from parent topics.
6486
6487 *** Article editing has been revamped and is now usable.
6488
6489 *** Signatures can be recognized in more intelligent fashions.
6490 See `gnus-signature-separator' and `gnus-signature-limit'.
6491
6492 *** Summary pick mode has been made to look more nn-like.
6493 Line numbers are displayed and the `.' command can be
6494 used to pick articles.
6495
6496 *** Commands for moving the .newsrc.eld from one server to
6497 another have been added.
6498
6499 `M-x gnus-change-server'
6500
6501 *** A way to specify that "uninteresting" fields be suppressed when
6502 generating lines in buffers.
6503
6504 *** Several commands in the group buffer can be undone with
6505 `M-C-_'.
6506
6507 *** Scoring can be done on words using the new score type `w'.
6508
6509 *** Adaptive scoring can be done on a Subject word-by-word basis:
6510
6511 (setq gnus-use-adaptive-scoring '(word))
6512
6513 *** Scores can be decayed.
6514
6515 (setq gnus-decay-scores t)
6516
6517 *** Scoring can be performed using a regexp on the Date header. The
6518 Date is normalized to compact ISO 8601 format first.
6519
6520 *** A new command has been added to remove all data on articles from
6521 the native server.
6522
6523 `M-x gnus-group-clear-data-on-native-groups'
6524
6525 *** A new command for reading collections of documents
6526 (nndoc with nnvirtual on top) has been added -- `M-C-d'.
6527
6528 *** Process mark sets can be pushed and popped.
6529
6530 *** A new mail-to-news backend makes it possible to post
6531 even when the NNTP server doesn't allow posting.
6532
6533 *** A new backend for reading searches from Web search engines
6534 (DejaNews, Alta Vista, InReference) has been added.
6535
6536 Use the `G w' command in the group buffer to create such
6537 a group.
6538
6539 *** Groups inside topics can now be sorted using the standard
6540 sorting functions, and each topic can be sorted independently.
6541
6542 See the commands under the `T S' submap.
6543
6544 *** Subsets of the groups can be sorted independently.
6545
6546 See the commands under the `G P' submap.
6547
6548 *** Cached articles can be pulled into the groups.
6549
6550 Use the `Y c' command.
6551
6552 *** Score files are now applied in a more reliable order.
6553
6554 *** Reports on where mail messages end up can be generated.
6555
6556 `M-x nnmail-split-history'
6557
6558 *** More hooks and functions have been added to remove junk
6559 from incoming mail before saving the mail.
6560
6561 See `nnmail-prepare-incoming-header-hook'.
6562
6563 *** The nnml mail backend now understands compressed article files.
6564
6565 *** To enable Gnus to read/post multi-lingual articles, you must execute
6566 the following code, for instance, in your .emacs.
6567
6568 (add-hook 'gnus-startup-hook 'gnus-mule-initialize)
6569
6570 Then, when you start Gnus, it will decode non-ASCII text automatically
6571 and show appropriate characters. (Note: if you are using gnus-mime
6572 from the SEMI package, formerly known as TM, you should NOT add this
6573 hook to gnus-startup-hook; gnus-mime has its own method of handling
6574 this issue.)
6575
6576 Since it is impossible to distinguish all coding systems
6577 automatically, you may need to specify a choice of coding system for a
6578 particular news group. This can be done by:
6579
6580 (gnus-mule-add-group NEWSGROUP 'CODING-SYSTEM)
6581
6582 Here NEWSGROUP should be a string which names a newsgroup or a tree
6583 of newsgroups. If NEWSGROUP is "XXX.YYY", all news groups under
6584 "XXX.YYY" (including "XXX.YYY.ZZZ") will use the specified coding
6585 system. CODING-SYSTEM specifies which coding system to use (for both
6586 for reading and posting).
6587
6588 CODING-SYSTEM can also be a cons cell of the form
6589 (READ-CODING-SYSTEM . POST-CODING-SYSTEM)
6590 Then READ-CODING-SYSTEM is used when you read messages from the
6591 newsgroups, while POST-CODING-SYSTEM is used when you post messages
6592 there.
6593
6594 Emacs knows the right coding systems for certain newsgroups by
6595 default. Here are some of these default settings:
6596
6597 (gnus-mule-add-group "fj" 'iso-2022-7)
6598 (gnus-mule-add-group "alt.chinese.text" 'hz-gb-2312)
6599 (gnus-mule-add-group "alt.hk" 'hz-gb-2312)
6600 (gnus-mule-add-group "alt.chinese.text.big5" 'cn-big5)
6601 (gnus-mule-add-group "soc.culture.vietnamese" '(nil . viqr))
6602
6603 When you reply by mail to an article, these settings are ignored;
6604 the mail is encoded according to sendmail-coding-system, as usual.
6605
6606 ** CC mode changes.
6607
6608 *** If you edit primarily one style of C (or C++, Objective-C, Java)
6609 code, you may want to make the CC Mode style variables have global
6610 values so that you can set them directly in your .emacs file. To do
6611 this, set c-style-variables-are-local-p to nil in your .emacs file.
6612 Note that this only takes effect if you do it *before* cc-mode.el is
6613 loaded.
6614
6615 If you typically edit more than one style of C (or C++, Objective-C,
6616 Java) code in a single Emacs session, you may want to make the CC Mode
6617 style variables have buffer local values. By default, all buffers
6618 share the same style variable settings; to make them buffer local, set
6619 c-style-variables-are-local-p to t in your .emacs file. Note that you
6620 must do this *before* CC Mode is loaded.
6621
6622 *** The new variable c-indentation-style holds the C style name
6623 of the current buffer.
6624
6625 *** The variable c-block-comments-indent-p has been deleted, because
6626 it is no longer necessary. C mode now handles all the supported styles
6627 of block comments, with no need to say which one you will use.
6628
6629 *** There is a new indentation style "python", which specifies the C
6630 style that the Python developers like.
6631
6632 *** There is a new c-cleanup-list option: brace-elseif-brace.
6633 This says to put ...} else if (...) {... on one line,
6634 just as brace-else-brace says to put ...} else {... on one line.
6635
6636 ** VC Changes [new]
6637
6638 ** In vc-retrieve-snapshot (C-x v r), if you don't specify a snapshot
6639 name, it retrieves the *latest* versions of all files in the current
6640 directory and its subdirectories (aside from files already locked).
6641
6642 This feature is useful if your RCS directory is a link to a common
6643 master directory, and you want to pick up changes made by other
6644 developers.
6645
6646 You can do the same thing for an individual file by typing C-u C-x C-q
6647 RET in a buffer visiting that file.
6648
6649 *** VC can now handle files under CVS that are being "watched" by
6650 other developers. Such files are made read-only by CVS. To get a
6651 writable copy, type C-x C-q in a buffer visiting such a file. VC then
6652 calls "cvs edit", which notifies the other developers of it.
6653
6654 *** vc-version-diff (C-u C-x v =) now suggests reasonable defaults for
6655 version numbers, based on the current state of the file.
6656
6657 ** Calendar changes.
6658
6659 A new function, list-holidays, allows you list holidays or subclasses
6660 of holidays for ranges of years. Related menu items allow you do this
6661 for the year of the selected date, or the following/previous years.
6662
6663 ** ps-print changes
6664
6665 There are some new user variables for customizing the page layout.
6666
6667 *** Paper size, paper orientation, columns
6668
6669 The variable `ps-paper-type' determines the size of paper ps-print
6670 formats for; it should contain one of the symbols:
6671 `a4' `a3' `letter' `legal' `letter-small' `tabloid'
6672 `ledger' `statement' `executive' `a4small' `b4' `b5'
6673 It defaults to `letter'.
6674 If you need other sizes, see the variable `ps-page-dimensions-database'.
6675
6676 The variable `ps-landscape-mode' determines the orientation
6677 of the printing on the page. nil, the default, means "portrait" mode,
6678 non-nil means "landscape" mode.
6679
6680 The variable `ps-number-of-columns' must be a positive integer.
6681 It determines the number of columns both in landscape and portrait mode.
6682 It defaults to 1.
6683
6684 *** Horizontal layout
6685
6686 The horizontal layout is determined by the variables
6687 `ps-left-margin', `ps-inter-column', and `ps-right-margin'.
6688 All are measured in points.
6689
6690 *** Vertical layout
6691
6692 The vertical layout is determined by the variables
6693 `ps-bottom-margin', `ps-top-margin', and `ps-header-offset'.
6694 All are measured in points.
6695
6696 *** Headers
6697
6698 If the variable `ps-print-header' is nil, no header is printed. Then
6699 `ps-header-offset' is not relevant and `ps-top-margin' represents the
6700 margin above the text.
6701
6702 If the variable `ps-print-header-frame' is non-nil, a gaudy
6703 framing box is printed around the header.
6704
6705 The contents of the header are determined by `ps-header-lines',
6706 `ps-show-n-of-n', `ps-left-header' and `ps-right-header'.
6707
6708 The height of the header is determined by `ps-header-line-pad',
6709 `ps-header-font-family', `ps-header-title-font-size' and
6710 `ps-header-font-size'.
6711
6712 *** Font managing
6713
6714 The variable `ps-font-family' determines which font family is to be
6715 used for ordinary text. Its value must be a key symbol in the alist
6716 `ps-font-info-database'. You can add other font families by adding
6717 elements to this alist.
6718
6719 The variable `ps-font-size' determines the size of the font
6720 for ordinary text. It defaults to 8.5 points.
6721
6722 ** hideshow changes.
6723
6724 *** now supports hiding of blocks of single line comments (like // for
6725 C++, ; for lisp).
6726
6727 *** Support for java-mode added.
6728
6729 *** When doing `hs-hide-all' it is now possible to also hide the comments
6730 in the file if `hs-hide-comments-when-hiding-all' is set.
6731
6732 *** The new function `hs-hide-initial-comment' hides the the comments at
6733 the beginning of the files. Finally those huge RCS logs don't stay in your
6734 way! This is run by default when entering the `hs-minor-mode'.
6735
6736 *** Now uses overlays instead of `selective-display', so is more
6737 robust and a lot faster.
6738
6739 *** A block beginning can span multiple lines.
6740
6741 *** The new variable `hs-show-hidden-short-form' if t, directs hideshow
6742 to show only the beginning of a block when it is hidden. See the
6743 documentation for more details.
6744
6745 ** Changes in Enriched mode.
6746
6747 *** When you visit a file in enriched-mode, Emacs will make sure it is
6748 filled to the current fill-column. This behavior is now independent
6749 of the size of the window. When you save the file, the fill-column in
6750 use is stored as well, so that the whole buffer need not be refilled
6751 the next time unless the fill-column is different.
6752
6753 *** use-hard-newlines is now a minor mode. When it is enabled, Emacs
6754 distinguishes between hard and soft newlines, and treats hard newlines
6755 as paragraph boundaries. Otherwise all newlines inserted are marked
6756 as soft, and paragraph boundaries are determined solely from the text.
6757
6758 ** Font Lock mode
6759
6760 *** Custom support
6761
6762 The variables font-lock-face-attributes, font-lock-display-type and
6763 font-lock-background-mode are now obsolete; the recommended way to specify the
6764 faces to use for Font Lock mode is with M-x customize-group on the new custom
6765 group font-lock-highlighting-faces. If you set font-lock-face-attributes in
6766 your ~/.emacs file, Font Lock mode will respect its value. However, you should
6767 consider converting from setting that variable to using M-x customize.
6768
6769 You can still use X resources to specify Font Lock face appearances.
6770
6771 *** Maximum decoration
6772
6773 Fontification now uses the maximum level of decoration supported by
6774 default. Previously, fontification used a mode-specific default level
6775 of decoration, which is typically the minimum level of decoration
6776 supported. You can set font-lock-maximum-decoration to nil
6777 to get the old behavior.
6778
6779 *** New support
6780
6781 Support is now provided for Java, Objective-C, AWK and SIMULA modes.
6782
6783 Note that Font Lock mode can be turned on without knowing exactly what modes
6784 support Font Lock mode, via the command global-font-lock-mode.
6785
6786 *** Configurable support
6787
6788 Support for C, C++, Objective-C and Java can be more easily configured for
6789 additional types and classes via the new variables c-font-lock-extra-types,
6790 c++-font-lock-extra-types, objc-font-lock-extra-types and, you guessed it,
6791 java-font-lock-extra-types. These value of each of these variables should be a
6792 list of regexps matching the extra type names. For example, the default value
6793 of c-font-lock-extra-types is ("\\sw+_t") which means fontification follows the
6794 convention that C type names end in _t. This results in slower fontification.
6795
6796 Of course, you can change the variables that specify fontification in whatever
6797 way you wish, typically by adding regexps. However, these new variables make
6798 it easier to make specific and common changes for the fontification of types.
6799
6800 *** Adding highlighting patterns to existing support
6801
6802 You can use the new function font-lock-add-keywords to add your own
6803 highlighting patterns, such as for project-local or user-specific constructs,
6804 for any mode.
6805
6806 For example, to highlight `FIXME:' words in C comments, put:
6807
6808 (font-lock-add-keywords 'c-mode '(("\\<FIXME:" 0 font-lock-warning-face t)))
6809
6810 in your ~/.emacs.
6811
6812 *** New faces
6813
6814 Font Lock now defines two new faces, font-lock-builtin-face and
6815 font-lock-warning-face. These are intended to highlight builtin keywords,
6816 distinct from a language's normal keywords, and objects that should be brought
6817 to user attention, respectively. Various modes now use these new faces.
6818
6819 *** Changes to fast-lock support mode
6820
6821 The fast-lock package, one of the two Font Lock support modes, can now process
6822 cache files silently. You can use the new variable fast-lock-verbose, in the
6823 same way as font-lock-verbose, to control this feature.
6824
6825 *** Changes to lazy-lock support mode
6826
6827 The lazy-lock package, one of the two Font Lock support modes, can now fontify
6828 according to the true syntactic context relative to other lines. You can use
6829 the new variable lazy-lock-defer-contextually to control this feature. If
6830 non-nil, changes to the buffer will cause subsequent lines in the buffer to be
6831 refontified after lazy-lock-defer-time seconds of idle time. If nil, then only
6832 the modified lines will be refontified; this is the same as the previous Lazy
6833 Lock mode behaviour and the behaviour of Font Lock mode.
6834
6835 This feature is useful in modes where strings or comments can span lines.
6836 For example, if a string or comment terminating character is deleted, then if
6837 this feature is enabled subsequent lines in the buffer will be correctly
6838 refontified to reflect their new syntactic context. Previously, only the line
6839 containing the deleted character would be refontified and you would have to use
6840 the command M-g M-g (font-lock-fontify-block) to refontify some lines.
6841
6842 As a consequence of this new feature, two other variables have changed:
6843
6844 Variable `lazy-lock-defer-driven' is renamed `lazy-lock-defer-on-scrolling'.
6845 Variable `lazy-lock-defer-time' can now only be a time, i.e., a number.
6846 Buffer modes for which on-the-fly deferral applies can be specified via the
6847 new variable `lazy-lock-defer-on-the-fly'.
6848
6849 If you set these variables in your ~/.emacs, then you may have to change those
6850 settings.
6851
6852 ** Ada mode changes.
6853
6854 *** There is now better support for using find-file.el with Ada mode.
6855 If you switch between spec and body, the cursor stays in the same
6856 procedure (modulo overloading). If a spec has no body file yet, but
6857 you try to switch to its body file, Ada mode now generates procedure
6858 stubs.
6859
6860 *** There are two new commands:
6861 - `ada-make-local' : invokes gnatmake on the current buffer
6862 - `ada-check-syntax' : check syntax of current buffer.
6863
6864 The user options `ada-compiler-make', `ada-make-options',
6865 `ada-language-version', `ada-compiler-syntax-check', and
6866 `ada-compile-options' are used within these commands.
6867
6868 *** Ada mode can now work with Outline minor mode. The outline level
6869 is calculated from the indenting, not from syntactic constructs.
6870 Outlining does not work if your code is not correctly indented.
6871
6872 *** The new function `ada-gnat-style' converts the buffer to the style of
6873 formatting used in GNAT. It places two blanks after a comment start,
6874 places one blank between a word end and an opening '(', and puts one
6875 space between a comma and the beginning of a word.
6876
6877 ** Scheme mode changes.
6878
6879 *** Scheme mode indentation now uses many of the facilities of Lisp
6880 mode; therefore, the variables to customize it are the variables used
6881 for Lisp mode which have names starting with `lisp-'. The variables
6882 with names starting with `scheme-' which used to do this no longer
6883 have any effect.
6884
6885 If you want to use different indentation for Scheme and Lisp, this is
6886 still possible, but now you must do it by adding a hook to
6887 scheme-mode-hook, which could work by setting the `lisp-' indentation
6888 variables as buffer-local variables.
6889
6890 *** DSSSL mode is a variant of Scheme mode, for editing DSSSL scripts.
6891 Use M-x dsssl-mode.
6892
6893 ** Changes to the emacsclient program
6894
6895 *** If a socket can't be found, and environment variables LOGNAME or
6896 USER are set, emacsclient now looks for a socket based on the UID
6897 associated with the name. That is an emacsclient running as root
6898 can connect to an Emacs server started by a non-root user.
6899
6900 *** The emacsclient program now accepts an option --no-wait which tells
6901 it to return immediately without waiting for you to "finish" the
6902 buffer in Emacs.
6903
6904 *** The new option --alternate-editor allows to specify an editor to
6905 use if Emacs is not running. The environment variable
6906 ALTERNATE_EDITOR can be used for the same effect; the command line
6907 option takes precedence.
6908
6909 ** M-x eldoc-mode enables a minor mode in which the echo area
6910 constantly shows the parameter list for function being called at point
6911 (in Emacs Lisp and Lisp Interaction modes only).
6912
6913 ** C-x n d now runs the new command narrow-to-defun,
6914 which narrows the accessible parts of the buffer to just
6915 the current defun.
6916
6917 ** Emacs now handles the `--' argument in the standard way; all
6918 following arguments are treated as ordinary file names.
6919
6920 ** On MSDOS and Windows, the bookmark file is now called _emacs.bmk,
6921 and the saved desktop file is now called _emacs.desktop (truncated if
6922 necessary).
6923
6924 ** When you kill a buffer that visits a file,
6925 if there are any registers that save positions in the file,
6926 these register values no longer become completely useless.
6927 If you try to go to such a register with C-x j, then you are
6928 asked whether to visit the file again. If you say yes,
6929 it visits the file and then goes to the same position.
6930
6931 ** When you visit a file that changes frequently outside Emacs--for
6932 example, a log of output from a process that continues to run--it may
6933 be useful for Emacs to revert the file without querying you whenever
6934 you visit the file afresh with C-x C-f.
6935
6936 You can request this behavior for certain files by setting the
6937 variable revert-without-query to a list of regular expressions. If a
6938 file's name matches any of these regular expressions, find-file and
6939 revert-buffer revert the buffer without asking for permission--but
6940 only if you have not edited the buffer text yourself.
6941
6942 ** set-default-font has been renamed to set-frame-font
6943 since it applies only to the current frame.
6944
6945 ** In TeX mode, you can use the variable tex-main-file to specify the
6946 file for tex-file to run TeX on. (By default, tex-main-file is nil,
6947 and tex-file runs TeX on the current visited file.)
6948
6949 This is useful when you are editing a document that consists of
6950 multiple files. In each of the included files, you can set up a local
6951 variable list which specifies the top-level file of your document for
6952 tex-main-file. Then tex-file will run TeX on the whole document
6953 instead of just the file you are editing.
6954
6955 ** RefTeX mode
6956
6957 RefTeX mode is a new minor mode with special support for \label, \ref
6958 and \cite macros in LaTeX documents. RefTeX distinguishes labels of
6959 different environments (equation, figure, ...) and has full support for
6960 multifile documents. To use it, select a buffer with a LaTeX document and
6961 turn the mode on with M-x reftex-mode. Here are the main user commands:
6962
6963 C-c ( reftex-label
6964 Creates a label semi-automatically. RefTeX is context sensitive and
6965 knows which kind of label is needed.
6966
6967 C-c ) reftex-reference
6968 Offers in a menu all labels in the document, along with context of the
6969 label definition. The selected label is referenced as \ref{LABEL}.
6970
6971 C-c [ reftex-citation
6972 Prompts for a regular expression and displays a list of matching BibTeX
6973 database entries. The selected entry is cited with a \cite{KEY} macro.
6974
6975 C-c & reftex-view-crossref
6976 Views the cross reference of a \ref or \cite command near point.
6977
6978 C-c = reftex-toc
6979 Shows a table of contents of the (multifile) document. From there you
6980 can quickly jump to every section.
6981
6982 Under X, RefTeX installs a "Ref" menu in the menu bar, with additional
6983 commands. Press `?' to get help when a prompt mentions this feature.
6984 Full documentation and customization examples are in the file
6985 reftex.el. You can use the finder to view the file documentation:
6986 C-h p --> tex --> reftex.el
6987
6988 ** Changes in BibTeX mode.
6989
6990 *** Info documentation is now available.
6991
6992 *** Don't allow parentheses in string constants anymore. This confused
6993 both the BibTeX program and Emacs BibTeX mode.
6994
6995 *** Renamed variable bibtex-mode-user-optional-fields to
6996 bibtex-user-optional-fields.
6997
6998 *** Removed variable bibtex-include-OPTannote
6999 (use bibtex-user-optional-fields instead).
7000
7001 *** New interactive functions to copy and kill fields and complete
7002 entries to the BibTeX kill ring, from where they can be yanked back by
7003 appropriate functions.
7004
7005 *** New interactive functions for repositioning and marking of
7006 entries. They are bound by default to M-C-l and M-C-h.
7007
7008 *** New hook bibtex-clean-entry-hook. It is called after entry has
7009 been cleaned.
7010
7011 *** New variable bibtex-field-delimiters, which replaces variables
7012 bibtex-field-{left|right}-delimiter.
7013
7014 *** New variable bibtex-entry-delimiters to determine how entries
7015 shall be delimited.
7016
7017 *** Allow preinitialization of fields. See documentation of
7018 bibtex-user-optional-fields, bibtex-entry-field-alist, and
7019 bibtex-include-OPTkey for details.
7020
7021 *** Book and InBook entries require either an author or an editor
7022 field. This is now supported by bibtex.el. Alternative fields are
7023 prefixed with `ALT'.
7024
7025 *** New variable bibtex-entry-format, which replaces variable
7026 bibtex-clean-entry-zap-empty-opts and allows specification of many
7027 formatting options performed on cleaning an entry (see variable
7028 documentation).
7029
7030 *** Even more control on how automatic keys are generated. See
7031 documentation of bibtex-generate-autokey for details. Transcriptions
7032 for foreign languages other than German are now handled, too.
7033
7034 *** New boolean user option bibtex-comma-after-last-field to decide if
7035 comma should be inserted at end of last field.
7036
7037 *** New boolean user option bibtex-align-at-equal-sign to determine if
7038 alignment should be made at left side of field contents or at equal
7039 signs. New user options to control entry layout (e.g. indentation).
7040
7041 *** New function bibtex-fill-entry to realign entries.
7042
7043 *** New function bibtex-reformat to reformat region or buffer.
7044
7045 *** New function bibtex-convert-alien to convert a BibTeX database
7046 from alien sources.
7047
7048 *** New function bibtex-complete-key (similar to bibtex-complete-string)
7049 to complete prefix to a key defined in buffer. Mainly useful in
7050 crossref entries.
7051
7052 *** New function bibtex-count-entries to count entries in buffer or
7053 region.
7054
7055 *** Added support for imenu.
7056
7057 *** The function `bibtex-validate' now checks current region instead
7058 of buffer if mark is active. Now it shows all errors of buffer in a
7059 `compilation mode' buffer. You can use the normal commands (e.g.
7060 `next-error') for compilation modes to jump to errors.
7061
7062 *** New variable `bibtex-string-file-path' to determine where the files
7063 from `bibtex-string-files' are searched.
7064
7065 ** Iso Accents mode now supports Latin-3 as an alternative.
7066
7067 ** The command next-error now opens blocks hidden by hideshow.
7068
7069 ** The function using-unix-filesystems has been replaced by the
7070 functions add-untranslated-filesystem and remove-untranslated-filesystem.
7071 Each of these functions takes the name of a drive letter or directory
7072 as an argument.
7073
7074 When a filesystem is added as untranslated, all files on it are read
7075 and written in binary mode (no cr/lf translation is performed).
7076
7077 ** browse-url changes
7078
7079 *** New methods for: Grail (browse-url-generic), MMM (browse-url-mmm),
7080 Lynx in a separate xterm (browse-url-lynx-xterm) or in an Emacs window
7081 (browse-url-lynx-emacs), remote W3 (browse-url-w3-gnudoit), generic
7082 non-remote-controlled browsers (browse-url-generic) and associated
7083 customization variables.
7084
7085 *** New commands `browse-url-of-region' and `browse-url'.
7086
7087 *** URLs marked up with <URL:...> (RFC1738) work if broken across
7088 lines. Browsing methods can be associated with URL regexps
7089 (e.g. mailto: URLs) via `browse-url-browser-function'.
7090
7091 ** Changes in Ediff
7092
7093 *** Clicking Mouse-2 on a brief command description in Ediff control panel
7094 pops up the Info file for this command.
7095
7096 *** There is now a variable, ediff-autostore-merges, which controls whether
7097 the result of a merge is saved in a file. By default, this is done only when
7098 merge is done from a session group (eg, when merging files in two different
7099 directories).
7100
7101 *** Since Emacs 19.31 (this hasn't been announced before), Ediff can compare
7102 and merge groups of files residing in different directories, or revisions of
7103 files in the same directory.
7104
7105 *** Since Emacs 19.31, Ediff can apply multi-file patches interactively.
7106 The patches must be in the context format or GNU unified format. (The bug
7107 related to the GNU format has now been fixed.)
7108
7109 ** Changes in Viper
7110
7111 *** The startup file is now .viper instead of .vip
7112 *** All variable/function names have been changed to start with viper-
7113 instead of vip-.
7114 *** C-\ now simulates the meta-key in all Viper states.
7115 *** C-z in Insert state now escapes to Vi for the duration of the next
7116 Viper command. In Vi and Insert states, C-z behaves as before.
7117 *** C-c \ escapes to Vi for one command if Viper is in Insert or Emacs states.
7118 *** _ is no longer the meta-key in Vi state.
7119 *** The variable viper-insert-state-cursor-color can be used to change cursor
7120 color when Viper is in insert state.
7121 *** If search lands the cursor near the top or the bottom of the window,
7122 Viper pulls the window up or down to expose more context. The variable
7123 viper-adjust-window-after-search controls this behavior.
7124
7125 ** Etags changes.
7126
7127 *** In C, C++, Objective C and Java, Etags tags global variables by
7128 default. The resulting tags files are inflated by 30% on average.
7129 Use --no-globals to turn this feature off. Etags can also tag
7130 variables which are members of structure-like constructs, but it does
7131 not by default. Use --members to turn this feature on.
7132
7133 *** C++ member functions are now recognized as tags.
7134
7135 *** Java is tagged like C++. In addition, "extends" and "implements"
7136 constructs are tagged. Files are recognised by the extension .java.
7137
7138 *** Etags can now handle programs written in Postscript. Files are
7139 recognised by the extensions .ps and .pdb (Postscript with C syntax).
7140 In Postscript, tags are lines that start with a slash.
7141
7142 *** Etags now handles Objective C and Objective C++ code. The usual C and
7143 C++ tags are recognized in these languages; in addition, etags
7144 recognizes special Objective C syntax for classes, class categories,
7145 methods and protocols.
7146
7147 *** Etags also handles Cobol. Files are recognised by the extension
7148 .cobol. The tagged lines are those containing a word that begins in
7149 column 8 and ends in a full stop, i.e. anything that could be a
7150 paragraph name.
7151
7152 *** Regexps in Etags now support intervals, as in ed or grep. The syntax of
7153 an interval is \{M,N\}, and it means to match the preceding expression
7154 at least M times and as many as N times.
7155
7156 ** The format for specifying a custom format for time-stamp to insert
7157 in files has changed slightly.
7158
7159 With the new enhancements to the functionality of format-time-string,
7160 time-stamp-format will change to be eventually compatible with it.
7161 This conversion is being done in two steps to maintain compatibility
7162 with old time-stamp-format values.
7163
7164 In the new scheme, alternate case is signified by the number-sign
7165 (`#') modifier, rather than changing the case of the format character.
7166 This feature is as yet incompletely implemented for compatibility
7167 reasons.
7168
7169 In the old time-stamp-format, all numeric fields defaulted to their
7170 natural width. (With format-time-string, each format has a
7171 fixed-width default.) In this version, you can specify the colon
7172 (`:') modifier to a numeric conversion to mean "give me the historical
7173 time-stamp-format width default." Do not use colon if you are
7174 specifying an explicit width, as in "%02d".
7175
7176 Numbers are no longer truncated to the requested width, except in the
7177 case of "%02y", which continues to give a two-digit year. Digit
7178 truncation probably wasn't being used for anything else anyway.
7179
7180 The new formats will work with old versions of Emacs. New formats are
7181 being recommended now to allow time-stamp-format to change in the
7182 future to be compatible with format-time-string. The new forms being
7183 recommended now will continue to work then.
7184
7185 See the documentation string for the variable time-stamp-format for
7186 details.
7187
7188 ** There are some additional major modes:
7189
7190 dcl-mode, for editing VMS DCL files.
7191 m4-mode, for editing files of m4 input.
7192 meta-mode, for editing MetaFont and MetaPost source files.
7193
7194 ** In Shell mode, the command shell-copy-environment-variable lets you
7195 copy the value of a specified environment variable from the subshell
7196 into Emacs.
7197
7198 ** New Lisp packages include:
7199
7200 *** battery.el displays battery status for laptops.
7201
7202 *** M-x bruce (named after Lenny Bruce) is a program that might
7203 be used for adding some indecent words to your email.
7204
7205 *** M-x crisp-mode enables an emulation for the CRiSP editor.
7206
7207 *** M-x dirtrack arranges for better tracking of directory changes
7208 in shell buffers.
7209
7210 *** The new library elint.el provides for linting of Emacs Lisp code.
7211 See the documentation for `elint-initialize', `elint-current-buffer'
7212 and `elint-defun'.
7213
7214 *** M-x expand-add-abbrevs defines a special kind of abbrev which is
7215 meant for programming constructs. These abbrevs expand like ordinary
7216 ones, when you type SPC, but only at the end of a line and not within
7217 strings or comments.
7218
7219 These abbrevs can act as templates: you can define places within an
7220 abbrev for insertion of additional text. Once you expand the abbrev,
7221 you can then use C-x a p and C-x a n to move back and forth to these
7222 insertion points. Thus you can conveniently insert additional text
7223 at these points.
7224
7225 *** filecache.el remembers the location of files so that you
7226 can visit them by short forms of their names.
7227
7228 *** find-func.el lets you find the definition of the user-loaded
7229 Emacs Lisp function at point.
7230
7231 *** M-x handwrite converts text to a "handwritten" picture.
7232
7233 *** M-x iswitchb-buffer is a command for switching to a buffer, much like
7234 switch-buffer, but it reads the argument in a more helpful way.
7235
7236 *** M-x landmark implements a neural network for landmark learning.
7237
7238 *** M-x locate provides a convenient interface to the `locate' program.
7239
7240 *** M4 mode is a new mode for editing files of m4 input.
7241
7242 *** mantemp.el creates C++ manual template instantiations
7243 from the GCC error messages which indicate which instantiations are needed.
7244
7245 *** mouse-copy.el provides a one-click copy and move feature.
7246 You can drag a region with M-mouse-1, and it is automatically
7247 inserted at point. M-Shift-mouse-1 deletes the text from its
7248 original place after inserting the copy.
7249
7250 *** mouse-drag.el lets you do scrolling by dragging Mouse-2
7251 on the buffer.
7252
7253 You click the mouse and move; that distance either translates into the
7254 velocity to scroll (with mouse-drag-throw) or the distance to scroll
7255 (with mouse-drag-drag). Horizontal scrolling is enabled when needed.
7256
7257 Enable mouse-drag with:
7258 (global-set-key [down-mouse-2] 'mouse-drag-throw)
7259 -or-
7260 (global-set-key [down-mouse-2] 'mouse-drag-drag)
7261
7262 *** mspools.el is useful for determining which mail folders have
7263 mail waiting to be read in them. It works with procmail.
7264
7265 *** Octave mode is a major mode for editing files of input for Octave.
7266 It comes with a facility for communicating with an Octave subprocess.
7267
7268 *** ogonek
7269
7270 The ogonek package provides functions for changing the coding of
7271 Polish diacritic characters in buffers. Codings known from various
7272 platforms are supported such as ISO8859-2, Mazovia, IBM Latin2, and
7273 TeX. For example, you can change the coding from Mazovia to
7274 ISO8859-2. Another example is a change of coding from ISO8859-2 to
7275 prefix notation (in which `/a' stands for the aogonek character, for
7276 instance) and vice versa.
7277
7278 To use this package load it using
7279 M-x load-library [enter] ogonek
7280 Then, you may get an explanation by calling one of
7281 M-x ogonek-jak -- in Polish
7282 M-x ogonek-how -- in English
7283 The info specifies the commands and variables provided as well as the
7284 ways of customization in `.emacs'.
7285
7286 *** Interface to ph.
7287
7288 Emacs provides a client interface to CCSO Nameservers (ph/qi)
7289
7290 The CCSO nameserver is used in many universities to provide directory
7291 services about people. ph.el provides a convenient Emacs interface to
7292 these servers.
7293
7294 *** uce.el is useful for replying to unsolicited commercial email.
7295
7296 *** vcursor.el implements a "virtual cursor" feature.
7297 You can move the virtual cursor with special commands
7298 while the real cursor does not move.
7299
7300 *** webjump.el is a "hot list" package which you can set up
7301 for visiting your favorite web sites.
7302
7303 *** M-x winner-mode is a minor mode which saves window configurations,
7304 so you can move back to other configurations that you have recently used.
7305
7306 ** movemail change
7307
7308 Movemail no longer needs to be installed setuid root in order for POP
7309 mail retrieval to function properly. This is because it no longer
7310 supports the RPOP (reserved-port POP) protocol; instead, it uses the
7311 user's POP password to authenticate to the mail server.
7312
7313 This change was made earlier, but not reported in NEWS before.
7314 \f
7315 * Emacs 20.1 changes for MS-DOS and MS-Windows.
7316
7317 ** Changes in handling MS-DOS/MS-Windows text files.
7318
7319 Emacs handles three different conventions for representing
7320 end-of-line: CRLF for MSDOS, LF for Unix and GNU, and CR (used on the
7321 Macintosh). Emacs determines which convention is used in a specific
7322 file based on the contents of that file (except for certain special
7323 file names), and when it saves the file, it uses the same convention.
7324
7325 To save the file and change the end-of-line convention, you can use
7326 C-x RET f (set-buffer-file-coding-system) to specify a different
7327 coding system for the buffer. Then, when you save the file, the newly
7328 specified coding system will take effect. For example, to save with
7329 LF, specify undecided-unix (or some other ...-unix coding system); to
7330 save with CRLF, specify undecided-dos.
7331 \f
7332 * Lisp Changes in Emacs 20.1
7333
7334 ** Byte-compiled files made with Emacs 20 will, in general, work in
7335 Emacs 19 as well, as long as the source code runs in Emacs 19. And
7336 vice versa: byte-compiled files made with Emacs 19 should also run in
7337 Emacs 20, as long as the program itself works in Emacs 20.
7338
7339 ** Windows-specific functions and variables have been renamed
7340 to start with w32- instead of win32-.
7341
7342 In hacker language, calling something a "win" is a form of praise. We
7343 don't want to praise a non-free Microsoft system, so we don't call it
7344 "win".
7345
7346 ** Basic Lisp changes
7347
7348 *** A symbol whose name starts with a colon now automatically
7349 evaluates to itself. Therefore such a symbol can be used as a constant.
7350
7351 *** The defined purpose of `defconst' has been changed. It should now
7352 be used only for values that should not be changed whether by a program
7353 or by the user.
7354
7355 The actual behavior of defconst has not been changed.
7356
7357 *** There are new macros `when' and `unless'
7358
7359 (when CONDITION BODY...) is short for (if CONDITION (progn BODY...))
7360 (unless CONDITION BODY...) is short for (if CONDITION nil BODY...)
7361
7362 *** Emacs now defines functions caar, cadr, cdar and cddr with their
7363 usual Lisp meanings. For example, caar returns the car of the car of
7364 its argument.
7365
7366 *** equal, when comparing strings, now ignores their text properties.
7367
7368 *** The new function `functionp' tests whether an object is a function.
7369
7370 *** arrayp now returns t for char-tables and bool-vectors.
7371
7372 *** Certain primitives which use characters (as integers) now get an
7373 error if the integer is not a valid character code. These primitives
7374 include insert-char, char-to-string, and the %c construct in the
7375 `format' function.
7376
7377 *** The `require' function now insists on adding a suffix, either .el
7378 or .elc, to the file name. Thus, (require 'foo) will not use a file
7379 whose name is just foo. It insists on foo.el or foo.elc.
7380
7381 *** The `autoload' function, when the file name does not contain
7382 either a directory name or the suffix .el or .elc, insists on
7383 adding one of these suffixes.
7384
7385 *** string-to-number now takes an optional second argument BASE
7386 which specifies the base to use when converting an integer.
7387 If BASE is omitted, base 10 is used.
7388
7389 We have not implemented other radices for floating point numbers,
7390 because that would be much more work and does not seem useful.
7391
7392 *** substring now handles vectors as well as strings.
7393
7394 *** The Common Lisp function eql is no longer defined normally.
7395 You must load the `cl' library to define it.
7396
7397 *** The new macro `with-current-buffer' lets you evaluate an expression
7398 conveniently with a different current buffer. It looks like this:
7399
7400 (with-current-buffer BUFFER BODY-FORMS...)
7401
7402 BUFFER is the expression that says which buffer to use.
7403 BODY-FORMS say what to do in that buffer.
7404
7405 *** The new primitive `save-current-buffer' saves and restores the
7406 choice of current buffer, like `save-excursion', but without saving or
7407 restoring the value of point or the mark. `with-current-buffer'
7408 works using `save-current-buffer'.
7409
7410 *** The new macro `with-temp-file' lets you do some work in a new buffer and
7411 write the output to a specified file. Like `progn', it returns the value
7412 of the last form.
7413
7414 *** The new macro `with-temp-buffer' lets you do some work in a new buffer,
7415 which is discarded after use. Like `progn', it returns the value of the
7416 last form. If you wish to return the buffer contents, use (buffer-string)
7417 as the last form.
7418
7419 *** The new function split-string takes a string, splits it at certain
7420 characters, and returns a list of the substrings in between the
7421 matches.
7422
7423 For example, (split-string "foo bar lose" " +") returns ("foo" "bar" "lose").
7424
7425 *** The new macro with-output-to-string executes some Lisp expressions
7426 with standard-output set up so that all output feeds into a string.
7427 Then it returns that string.
7428
7429 For example, if the current buffer name is `foo',
7430
7431 (with-output-to-string
7432 (princ "The buffer is ")
7433 (princ (buffer-name)))
7434
7435 returns "The buffer is foo".
7436
7437 ** Non-ASCII characters are now supported, if enable-multibyte-characters
7438 is non-nil.
7439
7440 These characters have character codes above 256. When inserted in the
7441 buffer or stored in a string, they are represented as multibyte
7442 characters that occupy several buffer positions each.
7443
7444 *** When enable-multibyte-characters is non-nil, a single character in
7445 a buffer or string can be two or more bytes (as many as four).
7446
7447 Buffers and strings are still made up of unibyte elements;
7448 character positions and string indices are always measured in bytes.
7449 Therefore, moving forward one character can increase the buffer
7450 position by 2, 3 or 4. The function forward-char moves by whole
7451 characters, and therefore is no longer equivalent to
7452 (lambda (n) (goto-char (+ (point) n))).
7453
7454 ASCII characters (codes 0 through 127) are still single bytes, always.
7455 Sequences of byte values 128 through 255 are used to represent
7456 non-ASCII characters. These sequences are called "multibyte
7457 characters".
7458
7459 The first byte of a multibyte character is always in the range 128
7460 through 159 (octal 0200 through 0237). These values are called
7461 "leading codes". The second and subsequent bytes are always in the
7462 range 160 through 255 (octal 0240 through 0377). The first byte, the
7463 leading code, determines how many bytes long the sequence is.
7464
7465 *** The function forward-char moves over characters, and therefore
7466 (forward-char 1) may increase point by more than 1 if it moves over a
7467 multibyte character. Likewise, delete-char always deletes a
7468 character, which may be more than one buffer position.
7469
7470 This means that some Lisp programs, which assume that a character is
7471 always one buffer position, need to be changed.
7472
7473 However, all ASCII characters are always one buffer position.
7474
7475 *** The regexp [\200-\377] no longer matches all non-ASCII characters,
7476 because when enable-multibyte-characters is non-nil, these characters
7477 have codes that are not in the range octal 200 to octal 377. However,
7478 the regexp [^\000-\177] does match all non-ASCII characters,
7479 guaranteed.
7480
7481 *** The function char-boundary-p returns non-nil if position POS is
7482 between two characters in the buffer (not in the middle of a
7483 character).
7484
7485 When the value is non-nil, it says what kind of character follows POS:
7486
7487 0 if POS is at an ASCII character or at the end of range,
7488 1 if POS is before a 2-byte length multi-byte form,
7489 2 if POS is at a head of 3-byte length multi-byte form,
7490 3 if POS is at a head of 4-byte length multi-byte form,
7491 4 if POS is at a head of multi-byte form of a composite character.
7492
7493 *** The function char-bytes returns how many bytes the character CHAR uses.
7494
7495 *** Strings can contain multibyte characters. The function
7496 `length' returns the string length counting bytes, which may be
7497 more than the number of characters.
7498
7499 You can include a multibyte character in a string constant by writing
7500 it literally. You can also represent it with a hex escape,
7501 \xNNNNNNN..., using as many digits as necessary. Any character which
7502 is not a valid hex digit terminates this construct. If you want to
7503 follow it with a character that is a hex digit, write backslash and
7504 newline in between; that will terminate the hex escape.
7505
7506 *** The function concat-chars takes arguments which are characters
7507 and returns a string containing those characters.
7508
7509 *** The function sref access a multibyte character in a string.
7510 (sref STRING INDX) returns the character in STRING at INDEX. INDEX
7511 counts from zero. If INDEX is at a position in the middle of a
7512 character, sref signals an error.
7513
7514 *** The function chars-in-string returns the number of characters
7515 in a string. This is less than the length of the string, if the
7516 string contains multibyte characters (the length counts bytes).
7517
7518 *** The function chars-in-region returns the number of characters
7519 in a region from BEG to END. This is less than (- END BEG) if the
7520 region contains multibyte characters (the length counts bytes).
7521
7522 *** The function string-to-list converts a string to a list of
7523 the characters in it. string-to-vector converts a string
7524 to a vector of the characters in it.
7525
7526 *** The function store-substring alters part of the contents
7527 of a string. You call it as follows:
7528
7529 (store-substring STRING IDX OBJ)
7530
7531 This says to alter STRING, by storing OBJ starting at index IDX in
7532 STRING. OBJ may be either a character or a (smaller) string.
7533 This function really does alter the contents of STRING.
7534 Since it is impossible to change the length of an existing string,
7535 it is an error if OBJ doesn't fit within STRING's actual length.
7536
7537 *** char-width returns the width (in columns) of the character CHAR,
7538 if it were displayed in the current buffer and the selected window.
7539
7540 *** string-width returns the width (in columns) of the text in STRING,
7541 if it were displayed in the current buffer and the selected window.
7542
7543 *** truncate-string-to-width shortens a string, if necessary,
7544 to fit within a certain number of columns. (Of course, it does
7545 not alter the string that you give it; it returns a new string
7546 which contains all or just part of the existing string.)
7547
7548 (truncate-string-to-width STR END-COLUMN &optional START-COLUMN PADDING)
7549
7550 This returns the part of STR up to column END-COLUMN.
7551
7552 The optional argument START-COLUMN specifies the starting column.
7553 If this is non-nil, then the first START-COLUMN columns of the string
7554 are not included in the resulting value.
7555
7556 The optional argument PADDING, if non-nil, is a padding character to be added
7557 at the beginning and end the resulting string, to extend it to exactly
7558 WIDTH columns. If PADDING is nil, that means do not pad; then, if STRING
7559 is narrower than WIDTH, the value is equal to STRING.
7560
7561 If PADDING and START-COLUMN are both non-nil, and if there is no clean
7562 place in STRING that corresponds to START-COLUMN (because one
7563 character extends across that column), then the padding character
7564 PADDING is added one or more times at the beginning of the result
7565 string, so that its columns line up as if it really did start at
7566 column START-COLUMN.
7567
7568 *** When the functions in the list after-change-functions are called,
7569 the third argument is the number of bytes in the pre-change text, not
7570 necessarily the number of characters. It is, in effect, the
7571 difference in buffer position between the beginning and the end of the
7572 changed text, before the change.
7573
7574 *** The characters Emacs uses are classified in various character
7575 sets, each of which has a name which is a symbol. In general there is
7576 one character set for each script, not for each language.
7577
7578 **** The function charsetp tests whether an object is a character set name.
7579
7580 **** The variable charset-list holds a list of character set names.
7581
7582 **** char-charset, given a character code, returns the name of the character
7583 set that the character belongs to. (The value is a symbol.)
7584
7585 **** split-char, given a character code, returns a list containing the
7586 name of the character set, followed by one or two byte-values
7587 which identify the character within that character set.
7588
7589 **** make-char, given a character set name and one or two subsequent
7590 byte-values, constructs a character code. This is roughly the
7591 opposite of split-char.
7592
7593 **** find-charset-region returns a list of the character sets
7594 of all the characters between BEG and END.
7595
7596 **** find-charset-string returns a list of the character sets
7597 of all the characters in a string.
7598
7599 *** Here are the Lisp facilities for working with coding systems
7600 and specifying coding systems.
7601
7602 **** The function coding-system-list returns a list of all coding
7603 system names (symbols). With optional argument t, it returns a list
7604 of all distinct base coding systems, not including variants.
7605 (Variant coding systems are those like latin-1-dos, latin-1-unix
7606 and latin-1-mac which specify the end-of-line conversion as well
7607 as what to do about code conversion.)
7608
7609 **** coding-system-p tests a symbol to see if it is a coding system
7610 name. It returns t if so, nil if not.
7611
7612 **** file-coding-system-alist specifies which coding systems to use
7613 for certain file names. It works like network-coding-system-alist,
7614 except that the PATTERN is matched against the file name.
7615
7616 Each element has the format (PATTERN . VAL), where PATTERN determines
7617 which file names the element applies to. PATTERN should be a regexp
7618 to match against a file name.
7619
7620 VAL is a coding system, a cons cell containing two coding systems, or
7621 a function symbol. If VAL is a coding system, it is used for both
7622 decoding what received from the network stream and encoding what sent
7623 to the network stream. If VAL is a cons cell containing two coding
7624 systems, the car specifies the coding system for decoding, and the cdr
7625 specifies the coding system for encoding.
7626
7627 If VAL is a function symbol, the function must return a coding system
7628 or a cons cell containing two coding systems, which is used as above.
7629
7630 **** The variable network-coding-system-alist specifies
7631 the coding system to use for network sockets.
7632
7633 Each element has the format (PATTERN . VAL), where PATTERN determines
7634 which network sockets the element applies to. PATTERN should be
7635 either a port number or a regular expression matching some network
7636 service names.
7637
7638 VAL is a coding system, a cons cell containing two coding systems, or
7639 a function symbol. If VAL is a coding system, it is used for both
7640 decoding what received from the network stream and encoding what sent
7641 to the network stream. If VAL is a cons cell containing two coding
7642 systems, the car specifies the coding system for decoding, and the cdr
7643 specifies the coding system for encoding.
7644
7645 If VAL is a function symbol, the function must return a coding system
7646 or a cons cell containing two coding systems, which is used as above.
7647
7648 **** process-coding-system-alist specifies which coding systems to use
7649 for certain subprocess. It works like network-coding-system-alist,
7650 except that the PATTERN is matched against the program name used to
7651 start the subprocess.
7652
7653 **** The variable default-process-coding-system specifies the coding
7654 systems to use for subprocess (and net connection) input and output,
7655 when nothing else specifies what to do. The value is a cons cell
7656 (OUTPUT-CODING . INPUT-CODING). OUTPUT-CODING applies to output
7657 to the subprocess, and INPUT-CODING applies to input from it.
7658
7659 **** The variable coding-system-for-write, if non-nil, specifies the
7660 coding system to use for writing a file, or for output to a synchronous
7661 subprocess.
7662
7663 It also applies to any asynchronous subprocess or network connection,
7664 but in a different way: the value of coding-system-for-write when you
7665 start the subprocess or connection affects that subprocess or
7666 connection permanently or until overridden.
7667
7668 The variable coding-system-for-write takes precedence over
7669 file-coding-system-alist, process-coding-system-alist and
7670 network-coding-system-alist, and all other methods of specifying a
7671 coding system for output. But most of the time this variable is nil.
7672 It exists so that Lisp programs can bind it to a specific coding
7673 system for one operation at a time.
7674
7675 **** coding-system-for-read applies similarly to input from
7676 files, subprocesses or network connections.
7677
7678 **** The function process-coding-system tells you what
7679 coding systems(s) an existing subprocess is using.
7680 The value is a cons cell,
7681 (DECODING-CODING-SYSTEM . ENCODING-CODING-SYSTEM)
7682 where DECODING-CODING-SYSTEM is used for decoding output from
7683 the subprocess, and ENCODING-CODING-SYSTEM is used for encoding
7684 input to the subprocess.
7685
7686 **** The function set-process-coding-system can be used to
7687 change the coding systems in use for an existing subprocess.
7688
7689 ** Emacs has a new facility to help users manage the many
7690 customization options. To make a Lisp program work with this facility,
7691 you need to use the new macros defgroup and defcustom.
7692
7693 You use defcustom instead of defvar, for defining a user option
7694 variable. The difference is that you specify two additional pieces of
7695 information (usually): the "type" which says what values are
7696 legitimate, and the "group" which specifies the hierarchy for
7697 customization.
7698
7699 Thus, instead of writing
7700
7701 (defvar foo-blurgoze nil
7702 "*Non-nil means that foo will act very blurgozely.")
7703
7704 you would now write this:
7705
7706 (defcustom foo-blurgoze nil
7707 "*Non-nil means that foo will act very blurgozely."
7708 :type 'boolean
7709 :group foo)
7710
7711 The type `boolean' means that this variable has only
7712 two meaningful states: nil and non-nil. Other type values
7713 describe other possibilities; see the manual for Custom
7714 for a description of them.
7715
7716 The "group" argument is used to specify a group which the option
7717 should belong to. You define a new group like this:
7718
7719 (defgroup ispell nil
7720 "Spell checking using Ispell."
7721 :group 'processes)
7722
7723 The "group" argument in defgroup specifies the parent group. The root
7724 group is called `emacs'; it should not contain any variables itself,
7725 but only other groups. The immediate subgroups of `emacs' correspond
7726 to the keywords used by C-h p. Under these subgroups come
7727 second-level subgroups that belong to individual packages.
7728
7729 Each Emacs package should have its own set of groups. A simple
7730 package should have just one group; a more complex package should
7731 have a hierarchy of its own groups. The sole or root group of a
7732 package should be a subgroup of one or more of the "keyword"
7733 first-level subgroups.
7734
7735 ** New `widget' library for inserting UI components in buffers.
7736
7737 This library, used by the new custom library, is documented in a
7738 separate manual that accompanies Emacs.
7739
7740 ** easy-mmode
7741
7742 The easy-mmode package provides macros and functions that make
7743 developing minor modes easier. Roughly, the programmer has to code
7744 only the functionality of the minor mode. All the rest--toggles,
7745 predicate, and documentation--can be done in one call to the macro
7746 `easy-mmode-define-minor-mode' (see the documentation). See also
7747 `easy-mmode-define-keymap'.
7748
7749 ** Text property changes
7750
7751 *** The `intangible' property now works on overlays as well as on a
7752 text property.
7753
7754 *** The new functions next-char-property-change and
7755 previous-char-property-change scan through the buffer looking for a
7756 place where either a text property or an overlay might change. The
7757 functions take two arguments, POSITION and LIMIT. POSITION is the
7758 starting position for the scan. LIMIT says where to stop the scan.
7759
7760 If no property change is found before LIMIT, the value is LIMIT. If
7761 LIMIT is nil, scan goes to the beginning or end of the accessible part
7762 of the buffer. If no property change is found, the value is the
7763 position of the beginning or end of the buffer.
7764
7765 *** In the `local-map' text property or overlay property, the property
7766 value can now be a symbol whose function definition is a keymap. This
7767 is an alternative to using the keymap itself.
7768
7769 ** Changes in invisibility features
7770
7771 *** Isearch can now temporarily show parts of the buffer which are
7772 hidden by an overlay with a invisible property, when the search match
7773 is inside that portion of the buffer. To enable this the overlay
7774 should have a isearch-open-invisible property which is a function that
7775 would be called having the overlay as an argument, the function should
7776 make the overlay visible.
7777
7778 During incremental search the overlays are shown by modifying the
7779 invisible and intangible properties, if beside this more actions are
7780 needed the overlay should have a isearch-open-invisible-temporary
7781 which is a function. The function is called with 2 arguments: one is
7782 the overlay and the second is nil when it should show the overlay and
7783 t when it should hide it.
7784
7785 *** add-to-invisibility-spec, remove-from-invisibility-spec
7786
7787 Modes that use overlays to hide portions of a buffer should set the
7788 invisible property of the overlay to the mode's name (or another symbol)
7789 and modify the `buffer-invisibility-spec' to include that symbol.
7790 Use `add-to-invisibility-spec' and `remove-from-invisibility-spec' to
7791 manipulate the `buffer-invisibility-spec'.
7792 Here is an example of how to do this:
7793
7794 ;; If we want to display an ellipsis:
7795 (add-to-invisibility-spec '(my-symbol . t))
7796 ;; If you don't want ellipsis:
7797 (add-to-invisibility-spec 'my-symbol)
7798
7799 ...
7800 (overlay-put (make-overlay beginning end) 'invisible 'my-symbol)
7801
7802 ...
7803 ;; When done with the overlays:
7804 (remove-from-invisibility-spec '(my-symbol . t))
7805 ;; Or respectively:
7806 (remove-from-invisibility-spec 'my-symbol)
7807
7808 ** Changes in syntax parsing.
7809
7810 *** The syntax-directed buffer-scan functions (such as
7811 `parse-partial-sexp', `forward-word' and similar functions) can now
7812 obey syntax information specified by text properties, if the variable
7813 `parse-sexp-lookup-properties' is non-nil.
7814
7815 If the value of `parse-sexp-lookup-properties' is nil, the behavior
7816 is as before: the syntax-table of the current buffer is always
7817 used to determine the syntax of the character at the position.
7818
7819 When `parse-sexp-lookup-properties' is non-nil, the syntax of a
7820 character in the buffer is calculated thus:
7821
7822 a) if the `syntax-table' text-property of that character
7823 is a cons, this cons becomes the syntax-type;
7824
7825 Valid values of `syntax-table' text-property are: nil, a valid
7826 syntax-table, and a valid syntax-table element, i.e.,
7827 a cons cell of the form (SYNTAX-CODE . MATCHING-CHAR).
7828
7829 b) if the character's `syntax-table' text-property
7830 is a syntax table, this syntax table is used
7831 (instead of the syntax-table of the current buffer) to
7832 determine the syntax type of the character.
7833
7834 c) otherwise the syntax-type is determined by the syntax-table
7835 of the current buffer.
7836
7837 *** The meaning of \s in regular expressions is also affected by the
7838 value of `parse-sexp-lookup-properties'. The details are the same as
7839 for the syntax-directed buffer-scan functions.
7840
7841 *** There are two new syntax-codes, `!' and `|' (numeric values 14
7842 and 15). A character with a code `!' starts a comment which is ended
7843 only by another character with the same code (unless quoted). A
7844 character with a code `|' starts a string which is ended only by
7845 another character with the same code (unless quoted).
7846
7847 These codes are mainly meant for use as values of the `syntax-table'
7848 text property.
7849
7850 *** The function `parse-partial-sexp' has new semantics for the sixth
7851 arg COMMENTSTOP. If it is `syntax-table', parse stops after the start
7852 of a comment or a string, or after end of a comment or a string.
7853
7854 *** The state-list which the return value from `parse-partial-sexp'
7855 (and can also be used as an argument) now has an optional ninth
7856 element: the character address of the start of last comment or string;
7857 nil if none. The fourth and eighth elements have special values if the
7858 string/comment is started by a "!" or "|" syntax-code.
7859
7860 *** Since new features of `parse-partial-sexp' allow a complete
7861 syntactic parsing, `font-lock' no longer supports
7862 `font-lock-comment-start-regexp'.
7863
7864 ** Changes in face features
7865
7866 *** The face functions are now unconditionally defined in Emacs, even
7867 if it does not support displaying on a device that supports faces.
7868
7869 *** The function face-documentation returns the documentation string
7870 of a face (or nil if it doesn't have one).
7871
7872 *** The function face-bold-p returns t if a face should be bold.
7873 set-face-bold-p sets that flag.
7874
7875 *** The function face-italic-p returns t if a face should be italic.
7876 set-face-italic-p sets that flag.
7877
7878 *** You can now specify foreground and background colors for text
7879 by adding elements of the form (foreground-color . COLOR-NAME)
7880 and (background-color . COLOR-NAME) to the list of faces in
7881 the `face' property (either the character's text property or an
7882 overlay property).
7883
7884 This means that you no longer need to create named faces to use
7885 arbitrary colors in a Lisp package.
7886
7887 ** Changes in file-handling functions
7888
7889 *** File-access primitive functions no longer discard an extra redundant
7890 directory name from the beginning of the file name. In other words,
7891 they no longer do anything special with // or /~. That conversion
7892 is now done only in substitute-in-file-name.
7893
7894 This makes it possible for a Lisp program to open a file whose name
7895 begins with ~.
7896
7897 *** If copy-file is unable to set the date of the output file,
7898 it now signals an error with the condition file-date-error.
7899
7900 *** The inode number returned by file-attributes may be an integer (if
7901 the number fits in a Lisp integer) or a list of integers.
7902
7903 *** insert-file-contents can now read from a special file,
7904 as long as the arguments VISIT and REPLACE are nil.
7905
7906 *** The RAWFILE arg to find-file-noselect, if non-nil, now suppresses
7907 character code conversion as well as other things.
7908
7909 Meanwhile, this feature does work with remote file names
7910 (formerly it did not).
7911
7912 *** Lisp packages which create temporary files should use the TMPDIR
7913 environment variable to decide which directory to put them in.
7914
7915 *** interpreter-mode-alist elements now specify regexps
7916 instead of constant strings.
7917
7918 *** expand-file-name no longer treats `//' or `/~' specially. It used
7919 to delete all the text of a file name up through the first slash of
7920 any `//' or `/~' sequence. Now it passes them straight through.
7921
7922 substitute-in-file-name continues to treat those sequences specially,
7923 in the same way as before.
7924
7925 *** The variable `format-alist' is more general now.
7926 The FROM-FN and TO-FN in a format definition can now be strings
7927 which specify shell commands to use as filters to perform conversion.
7928
7929 *** The new function access-file tries to open a file, and signals an
7930 error if that fails. If the open succeeds, access-file does nothing
7931 else, and returns nil.
7932
7933 *** The function insert-directory now signals an error if the specified
7934 directory cannot be listed.
7935
7936 ** Changes in minibuffer input
7937
7938 *** The functions read-buffer, read-variable, read-command, read-string
7939 read-file-name, read-from-minibuffer and completing-read now take an
7940 additional argument which specifies the default value. If this
7941 argument is non-nil, it should be a string; that string is used in two
7942 ways:
7943
7944 It is returned if the user enters empty input.
7945 It is available through the history command M-n.
7946
7947 *** The functions read-string, read-from-minibuffer,
7948 read-no-blanks-input and completing-read now take an additional
7949 argument INHERIT-INPUT-METHOD. If this is non-nil, then the
7950 minibuffer inherits the current input method and the setting of
7951 enable-multibyte-characters from the previously current buffer.
7952
7953 In an interactive spec, you can use M instead of s to read an
7954 argument in this way.
7955
7956 *** All minibuffer input functions discard text properties
7957 from the text you enter in the minibuffer, unless the variable
7958 minibuffer-allow-text-properties is non-nil.
7959
7960 ** Echo area features
7961
7962 *** Clearing the echo area now runs the normal hook
7963 echo-area-clear-hook. Note that the echo area can be used while the
7964 minibuffer is active; in that case, the minibuffer is still active
7965 after the echo area is cleared.
7966
7967 *** The function current-message returns the message currently displayed
7968 in the echo area, or nil if there is none.
7969
7970 ** Keyboard input features
7971
7972 *** tty-erase-char is a new variable that reports which character was
7973 set up as the terminal's erase character when time Emacs was started.
7974
7975 *** num-nonmacro-input-events is the total number of input events
7976 received so far from the terminal. It does not count those generated
7977 by keyboard macros.
7978
7979 ** Frame-related changes
7980
7981 *** make-frame runs the normal hook before-make-frame-hook just before
7982 creating a frame, and just after creating a frame it runs the abnormal
7983 hook after-make-frame-functions with the new frame as arg.
7984
7985 *** The new hook window-configuration-change-hook is now run every time
7986 the window configuration has changed. The frame whose configuration
7987 has changed is the selected frame when the hook is run.
7988
7989 *** Each frame now independently records the order for recently
7990 selected buffers, in its buffer-list frame parameter, so that the
7991 value of other-buffer is now based on the buffers recently displayed
7992 in the selected frame.
7993
7994 *** The value of the frame parameter vertical-scroll-bars
7995 is now `left', `right' or nil. A non-nil value specifies
7996 which side of the window to put the scroll bars on.
7997
7998 ** X Windows features
7999
8000 *** You can examine X resources for other applications by binding
8001 x-resource-class around a call to x-get-resource. The usual value of
8002 x-resource-class is "Emacs", which is the correct value for Emacs.
8003
8004 *** In menus, checkboxes and radio buttons now actually work.
8005 The menu displays the current status of the box or button.
8006
8007 *** The function x-list-fonts now takes an optional fourth argument
8008 MAXIMUM which sets a limit on how many matching fonts to return.
8009 A smaller value of MAXIMUM makes the function faster.
8010
8011 If the only question is whether *any* font matches the pattern,
8012 it is good to supply 1 for this argument.
8013
8014 ** Subprocess features
8015
8016 *** A reminder: it is no longer necessary for subprocess filter
8017 functions and sentinels to do save-match-data, because Emacs does this
8018 automatically.
8019
8020 *** The new function shell-command-to-string executes a shell command
8021 and returns the output from the command as a string.
8022
8023 *** The new function process-contact returns t for a child process,
8024 and (HOSTNAME SERVICE) for a net connection.
8025
8026 ** An error in running pre-command-hook or post-command-hook
8027 does clear the variable to nil. The documentation was wrong before.
8028
8029 ** In define-key-after, if AFTER is t, the new binding now always goes
8030 at the end of the keymap. If the keymap is a menu, this means it
8031 goes after the other menu items.
8032
8033 ** If you have a program that makes several changes in the same area
8034 of the buffer, you can use the macro combine-after-change-calls
8035 around that Lisp code to make it faster when after-change hooks
8036 are in use.
8037
8038 The macro arranges to call the after-change functions just once for a
8039 series of several changes--if that seems safe.
8040
8041 Don't alter the variables after-change-functions and
8042 after-change-function within the body of a combine-after-change-calls
8043 form.
8044
8045 ** If you define an abbrev (with define-abbrev) whose EXPANSION
8046 is not a string, then the abbrev does not expand in the usual sense,
8047 but its hook is still run.
8048
8049 ** Normally, the Lisp debugger is not used (even if you have enabled it)
8050 for errors that are handled by condition-case.
8051
8052 If you set debug-on-signal to a non-nil value, then the debugger is called
8053 regardless of whether there is a handler for the condition. This is
8054 useful for debugging problems that happen inside of a condition-case.
8055
8056 This mode of operation seems to be unreliable in other ways. Errors that
8057 are normal and ought to be handled, perhaps in timers or process
8058 filters, will instead invoke the debugger. So don't say you weren't
8059 warned.
8060
8061 ** The new variable ring-bell-function lets you specify your own
8062 way for Emacs to "ring the bell".
8063
8064 ** If run-at-time's TIME argument is t, the action is repeated at
8065 integral multiples of REPEAT from the epoch; this is useful for
8066 functions like display-time.
8067
8068 ** You can use the function locate-library to find the precise file
8069 name of a Lisp library. This isn't new, but wasn't documented before.
8070
8071 ** Commands for entering view mode have new optional arguments that
8072 can be used from Lisp. Low-level entrance to and exit from view mode
8073 is done by functions view-mode-enter and view-mode-exit.
8074
8075 ** batch-byte-compile-file now makes Emacs return a nonzero status code
8076 if there is an error in compilation.
8077
8078 ** pop-to-buffer, switch-to-buffer-other-window and
8079 switch-to-buffer-other-frame now accept an additional optional
8080 argument NORECORD, much like switch-to-buffer. If it is non-nil,
8081 they don't put the buffer at the front of the buffer list.
8082
8083 ** If your .emacs file leaves the *scratch* buffer non-empty,
8084 Emacs does not display the startup message, so as to avoid changing
8085 the *scratch* buffer.
8086
8087 ** The new function regexp-opt returns an efficient regexp to match a string.
8088 The arguments are STRINGS and (optionally) PAREN. This function can be used
8089 where regexp matching or searching is intensively used and speed is important,
8090 e.g., in Font Lock mode.
8091
8092 ** The variable buffer-display-count is local to each buffer,
8093 and is incremented each time the buffer is displayed in a window.
8094 It starts at 0 when the buffer is created.
8095
8096 ** The new function compose-mail starts composing a mail message
8097 using the user's chosen mail composition agent (specified with the
8098 variable mail-user-agent). It has variants compose-mail-other-window
8099 and compose-mail-other-frame.
8100
8101 ** The `user-full-name' function now takes an optional parameter which
8102 can either be a number (the UID) or a string (the login name). The
8103 full name of the specified user will be returned.
8104
8105 ** Lisp packages that load files of customizations, or any other sort
8106 of user profile, should obey the variable init-file-user in deciding
8107 where to find it. They should load the profile of the user name found
8108 in that variable. If init-file-user is nil, meaning that the -q
8109 option was used, then Lisp packages should not load the customization
8110 files at all.
8111
8112 ** format-time-string now allows you to specify the field width
8113 and type of padding. This works as in printf: you write the field
8114 width as digits in the middle of a %-construct. If you start
8115 the field width with 0, it means to pad with zeros.
8116
8117 For example, %S normally specifies the number of seconds since the
8118 minute; %03S means to pad this with zeros to 3 positions, %_3S to pad
8119 with spaces to 3 positions. Plain %3S pads with zeros, because that
8120 is how %S normally pads to two positions.
8121
8122 ** thing-at-point now supports a new kind of "thing": url.
8123
8124 ** imenu.el changes.
8125
8126 You can now specify a function to be run when selecting an
8127 item from menu created by imenu.
8128
8129 An example of using this feature: if we define imenu items for the
8130 #include directives in a C file, we can open the included file when we
8131 select one of those items.
8132 \f
8133 * Emacs 19.34 is a bug-fix release with no user-visible changes.
8134 \f
8135 * Changes in Emacs 19.33.
8136
8137 ** Bibtex mode no longer turns on Auto Fill automatically. (No major
8138 mode should do that--it is the user's choice.)
8139
8140 ** The variable normal-auto-fill-function specifies the function to
8141 use for auto-fill-function, if and when Auto Fill is turned on.
8142 Major modes can set this locally to alter how Auto Fill works.
8143 \f
8144 * Editing Changes in Emacs 19.32
8145
8146 ** C-x f with no argument now signals an error.
8147 To set the fill column at the current column, use C-u C-x f.
8148
8149 ** Expanding dynamic abbrevs with M-/ is now smarter about case
8150 conversion. If you type the abbreviation with mixed case, and it
8151 matches the beginning of the expansion including case, then the
8152 expansion is copied verbatim. Using SPC M-/ to copy an additional
8153 word always copies it verbatim except when the previous copied word is
8154 all caps.
8155
8156 ** On a non-windowing terminal, which can display only one Emacs frame
8157 at a time, creating a new frame with C-x 5 2 also selects that frame.
8158
8159 When using a display that can show multiple frames at once, C-x 5 2
8160 does make the frame visible, but does not select it. This is the same
8161 as in previous Emacs versions.
8162
8163 ** You can use C-x 5 2 to create multiple frames on MSDOS, just as on a
8164 non-X terminal on Unix. Of course, only one frame is visible at any
8165 time, since your terminal doesn't have the ability to display multiple
8166 frames.
8167
8168 ** On Windows, set win32-pass-alt-to-system to a non-nil value
8169 if you would like tapping the Alt key to invoke the Windows menu.
8170 This feature is not enabled by default; since the Alt key is also the
8171 Meta key, it is too easy and painful to activate this feature by
8172 accident.
8173
8174 ** The command apply-macro-to-region-lines repeats the last defined
8175 keyboard macro once for each complete line within the current region.
8176 It does this line by line, by moving point to the beginning of that
8177 line and then executing the macro.
8178
8179 This command is not new, but was never documented before.
8180
8181 ** You can now use Mouse-1 to place the region around a string constant
8182 (something surrounded by doublequote characters or other delimiter
8183 characters of like syntax) by double-clicking on one of the delimiting
8184 characters.
8185
8186 ** Font Lock mode
8187
8188 *** Font Lock support modes
8189
8190 Font Lock can be configured to use Fast Lock mode and Lazy Lock mode (see
8191 below) in a flexible way. Rather than adding the appropriate function to the
8192 hook font-lock-mode-hook, you can use the new variable font-lock-support-mode
8193 to control which modes have Fast Lock mode or Lazy Lock mode turned on when
8194 Font Lock mode is enabled.
8195
8196 For example, to use Fast Lock mode when Font Lock mode is turned on, put:
8197
8198 (setq font-lock-support-mode 'fast-lock-mode)
8199
8200 in your ~/.emacs.
8201
8202 *** lazy-lock
8203
8204 The lazy-lock package speeds up Font Lock mode by making fontification occur
8205 only when necessary, such as when a previously unfontified part of the buffer
8206 becomes visible in a window. When you create a buffer with Font Lock mode and
8207 Lazy Lock mode turned on, the buffer is not fontified. When certain events
8208 occur (such as scrolling), Lazy Lock makes sure that the visible parts of the
8209 buffer are fontified. Lazy Lock also defers on-the-fly fontification until
8210 Emacs has been idle for a given amount of time.
8211
8212 To use this package, put in your ~/.emacs:
8213
8214 (setq font-lock-support-mode 'lazy-lock-mode)
8215
8216 To control the package behaviour, see the documentation for `lazy-lock-mode'.
8217
8218 ** Changes in BibTeX mode.
8219
8220 *** For all entries allow spaces and tabs between opening brace or
8221 paren and key.
8222
8223 *** Non-escaped double-quoted characters (as in `Sch"of') are now
8224 supported.
8225
8226 ** Gnus changes.
8227
8228 Gnus, the Emacs news reader, has undergone further rewriting. Many new
8229 commands and variables have been added. There should be no
8230 significant incompatibilities between this Gnus version and the
8231 previously released version, except in the message composition area.
8232
8233 Below is a list of the more user-visible changes. Coding changes
8234 between Gnus 5.1 and 5.2 are more extensive.
8235
8236 *** A new message composition mode is used. All old customization
8237 variables for mail-mode, rnews-reply-mode and gnus-msg are now
8238 obsolete.
8239
8240 *** Gnus is now able to generate "sparse" threads -- threads where
8241 missing articles are represented by empty nodes.
8242
8243 (setq gnus-build-sparse-threads 'some)
8244
8245 *** Outgoing articles are stored on a special archive server.
8246
8247 To disable this: (setq gnus-message-archive-group nil)
8248
8249 *** Partial thread regeneration now happens when articles are
8250 referred.
8251
8252 *** Gnus can make use of GroupLens predictions:
8253
8254 (setq gnus-use-grouplens t)
8255
8256 *** A trn-line tree buffer can be displayed.
8257
8258 (setq gnus-use-trees t)
8259
8260 *** An nn-like pick-and-read minor mode is available for the summary
8261 buffers.
8262
8263 (add-hook 'gnus-summary-mode-hook 'gnus-pick-mode)
8264
8265 *** In binary groups you can use a special binary minor mode:
8266
8267 `M-x gnus-binary-mode'
8268
8269 *** Groups can be grouped in a folding topic hierarchy.
8270
8271 (add-hook 'gnus-group-mode-hook 'gnus-topic-mode)
8272
8273 *** Gnus can re-send and bounce mail.
8274
8275 Use the `S D r' and `S D b'.
8276
8277 *** Groups can now have a score, and bubbling based on entry frequency
8278 is possible.
8279
8280 (add-hook 'gnus-summary-exit-hook 'gnus-summary-bubble-group)
8281
8282 *** Groups can be process-marked, and commands can be performed on
8283 groups of groups.
8284
8285 *** Caching is possible in virtual groups.
8286
8287 *** nndoc now understands all kinds of digests, mail boxes, rnews news
8288 batches, ClariNet briefs collections, and just about everything else.
8289
8290 *** Gnus has a new backend (nnsoup) to create/read SOUP packets.
8291
8292 *** The Gnus cache is much faster.
8293
8294 *** Groups can be sorted according to many criteria.
8295
8296 For instance: (setq gnus-group-sort-function 'gnus-group-sort-by-rank)
8297
8298 *** New group parameters have been introduced to set list-address and
8299 expiration times.
8300
8301 *** All formatting specs allow specifying faces to be used.
8302
8303 *** There are several more commands for setting/removing/acting on
8304 process marked articles on the `M P' submap.
8305
8306 *** The summary buffer can be limited to show parts of the available
8307 articles based on a wide range of criteria. These commands have been
8308 bound to keys on the `/' submap.
8309
8310 *** Articles can be made persistent -- as an alternative to saving
8311 articles with the `*' command.
8312
8313 *** All functions for hiding article elements are now toggles.
8314
8315 *** Article headers can be buttonized.
8316
8317 (add-hook 'gnus-article-display-hook 'gnus-article-add-buttons-to-head)
8318
8319 *** All mail backends support fetching articles by Message-ID.
8320
8321 *** Duplicate mail can now be treated properly. See the
8322 `nnmail-treat-duplicates' variable.
8323
8324 *** All summary mode commands are available directly from the article
8325 buffer.
8326
8327 *** Frames can be part of `gnus-buffer-configuration'.
8328
8329 *** Mail can be re-scanned by a daemonic process.
8330
8331 *** Gnus can make use of NoCeM files to filter spam.
8332
8333 (setq gnus-use-nocem t)
8334
8335 *** Groups can be made permanently visible.
8336
8337 (setq gnus-permanently-visible-groups "^nnml:")
8338
8339 *** Many new hooks have been introduced to make customizing easier.
8340
8341 *** Gnus respects the Mail-Copies-To header.
8342
8343 *** Threads can be gathered by looking at the References header.
8344
8345 (setq gnus-summary-thread-gathering-function
8346 'gnus-gather-threads-by-references)
8347
8348 *** Read articles can be stored in a special backlog buffer to avoid
8349 refetching.
8350
8351 (setq gnus-keep-backlog 50)
8352
8353 *** A clean copy of the current article is always stored in a separate
8354 buffer to allow easier treatment.
8355
8356 *** Gnus can suggest where to save articles. See `gnus-split-methods'.
8357
8358 *** Gnus doesn't have to do as much prompting when saving.
8359
8360 (setq gnus-prompt-before-saving t)
8361
8362 *** gnus-uu can view decoded files asynchronously while fetching
8363 articles.
8364
8365 (setq gnus-uu-grabbed-file-functions 'gnus-uu-grab-view)
8366
8367 *** Filling in the article buffer now works properly on cited text.
8368
8369 *** Hiding cited text adds buttons to toggle hiding, and how much
8370 cited text to hide is now customizable.
8371
8372 (setq gnus-cited-lines-visible 2)
8373
8374 *** Boring headers can be hidden.
8375
8376 (add-hook 'gnus-article-display-hook 'gnus-article-hide-boring-headers)
8377
8378 *** Default scoring values can now be set from the menu bar.
8379
8380 *** Further syntax checking of outgoing articles have been added.
8381
8382 The Gnus manual has been expanded. It explains all these new features
8383 in greater detail.
8384 \f
8385 * Lisp Changes in Emacs 19.32
8386
8387 ** The function set-visited-file-name now accepts an optional
8388 second argument NO-QUERY. If it is non-nil, then the user is not
8389 asked for confirmation in the case where the specified file already
8390 exists.
8391
8392 ** The variable print-length applies to printing vectors and bitvectors,
8393 as well as lists.
8394
8395 ** The new function keymap-parent returns the parent keymap
8396 of a given keymap.
8397
8398 ** The new function set-keymap-parent specifies a new parent for a
8399 given keymap. The arguments are KEYMAP and PARENT. PARENT must be a
8400 keymap or nil.
8401
8402 ** Sometimes menu keymaps use a command name, a symbol, which is really
8403 an automatically generated alias for some other command, the "real"
8404 name. In such a case, you should give that alias symbol a non-nil
8405 menu-alias property. That property tells the menu system to look for
8406 equivalent keys for the real name instead of equivalent keys for the
8407 alias.
8408 \f
8409 * Editing Changes in Emacs 19.31
8410
8411 ** Freedom of the press restricted in the United States.
8412
8413 Emacs has been censored in accord with the Communications Decency Act.
8414 This includes removing some features of the doctor program. That law
8415 was described by its supporters as a ban on pornography, but it bans
8416 far more than that. The Emacs distribution has never contained any
8417 pornography, but parts of it were nonetheless prohibited.
8418
8419 For information on US government censorship of the Internet, and what
8420 you can do to bring back freedom of the press, see the web site
8421 `http://www.vtw.org/'.
8422
8423 ** A note about C mode indentation customization.
8424
8425 The old (Emacs 19.29) ways of specifying a C indentation style
8426 do not normally work in the new implementation of C mode.
8427 It has its own methods of customizing indentation, which are
8428 much more powerful than the old C mode. See the Editing Programs
8429 chapter of the manual for details.
8430
8431 However, you can load the library cc-compat to make the old
8432 customization variables take effect.
8433
8434 ** Marking with the mouse.
8435
8436 When you mark a region with the mouse, the region now remains
8437 highlighted until the next input event, regardless of whether you are
8438 using M-x transient-mark-mode.
8439
8440 ** Improved Windows NT/95 support.
8441
8442 *** Emacs now supports scroll bars on Windows NT and Windows 95.
8443
8444 *** Emacs now supports subprocesses on Windows 95. (Subprocesses used
8445 to work on NT only and not on 95.)
8446
8447 *** There are difficulties with subprocesses, though, due to problems
8448 in Windows, beyond the control of Emacs. They work fine as long as
8449 you run Windows applications. The problems arise when you run a DOS
8450 application in a subprocesses. Since current shells run as DOS
8451 applications, these problems are significant.
8452
8453 If you run a DOS application in a subprocess, then the application is
8454 likely to busy-wait, which means that your machine will be 100% busy.
8455 However, if you don't mind the temporary heavy load, the subprocess
8456 will work OK as long as you tell it to terminate before you start any
8457 other DOS application as a subprocess.
8458
8459 Emacs is unable to terminate or interrupt a DOS subprocess.
8460 You have to do this by providing input directly to the subprocess.
8461
8462 If you run two DOS applications at the same time in two separate
8463 subprocesses, even if one of them is asynchronous, you will probably
8464 have to reboot your machine--until then, it will remain 100% busy.
8465 Windows simply does not cope when one Windows process tries to run two
8466 separate DOS subprocesses. Typing CTL-ALT-DEL and then choosing
8467 Shutdown seems to work although it may take a few minutes.
8468
8469 ** M-x resize-minibuffer-mode.
8470
8471 This command, not previously mentioned in NEWS, toggles a mode in
8472 which the minibuffer window expands to show as many lines as the
8473 minibuffer contains.
8474
8475 ** `title' frame parameter and resource.
8476
8477 The `title' X resource now specifies just the frame title, nothing else.
8478 It does not affect the name used for looking up other X resources.
8479 It works by setting the new `title' frame parameter, which likewise
8480 affects just the displayed title of the frame.
8481
8482 The `name' parameter continues to do what it used to do:
8483 it specifies the frame name for looking up X resources,
8484 and also serves as the default for the displayed title
8485 when the `title' parameter is unspecified or nil.
8486
8487 ** Emacs now uses the X toolkit by default, if you have a new
8488 enough version of X installed (X11R5 or newer).
8489
8490 ** When you compile Emacs with the Motif widget set, Motif handles the
8491 F10 key by activating the menu bar. To avoid confusion, the usual
8492 Emacs binding of F10 is replaced with a no-op when using Motif.
8493
8494 If you want to be able to use F10 in Emacs, you can rebind the Motif
8495 menubar to some other key which you don't use. To do so, add
8496 something like this to your X resources file. This example rebinds
8497 the Motif menu bar activation key to S-F12:
8498
8499 Emacs*defaultVirtualBindings: osfMenuBar : Shift<Key>F12
8500
8501 ** In overwrite mode, DEL now inserts spaces in most cases
8502 to replace the characters it "deletes".
8503
8504 ** The Rmail summary now shows the number of lines in each message.
8505
8506 ** Rmail has a new command M-x unforward-rmail-message, which extracts
8507 a forwarded message from the message that forwarded it. To use it,
8508 select a message which contains a forwarded message and then type the command.
8509 It inserts the forwarded message as a separate Rmail message
8510 immediately after the selected one.
8511
8512 This command also undoes the textual modifications that are standardly
8513 made, as part of forwarding, by Rmail and other mail reader programs.
8514
8515 ** Turning off saving of .saves-... files in your home directory.
8516
8517 Each Emacs session writes a file named .saves-... in your home
8518 directory to record which files M-x recover-session should recover.
8519 If you exit Emacs normally with C-x C-c, it deletes that file. If
8520 Emacs or the operating system crashes, the file remains for M-x
8521 recover-session.
8522
8523 You can turn off the writing of these files by setting
8524 auto-save-list-file-name to nil. If you do this, M-x recover-session
8525 will not work.
8526
8527 Some previous Emacs versions failed to delete these files even on
8528 normal exit. This is fixed now. If you are thinking of turning off
8529 this feature because of past experiences with versions that had this
8530 bug, it would make sense to check whether you still want to do so
8531 now that the bug is fixed.
8532
8533 ** Changes to Version Control (VC)
8534
8535 There is a new variable, vc-follow-symlinks. It indicates what to do
8536 when you visit a link to a file that is under version control.
8537 Editing the file through the link bypasses the version control system,
8538 which is dangerous and probably not what you want.
8539
8540 If this variable is t, VC follows the link and visits the real file,
8541 telling you about it in the echo area. If it is `ask' (the default),
8542 VC asks for confirmation whether it should follow the link. If nil,
8543 the link is visited and a warning displayed.
8544
8545 ** iso-acc.el now lets you specify a choice of language.
8546 Languages include "latin-1" (the default) and "latin-2" (which
8547 is designed for entering ISO Latin-2 characters).
8548
8549 There are also choices for specific human languages such as French and
8550 Portuguese. These are subsets of Latin-1, which differ in that they
8551 enable only the accent characters needed for particular language.
8552 The other accent characters, not needed for the chosen language,
8553 remain normal.
8554
8555 ** Posting articles and sending mail now has M-TAB completion on various
8556 header fields (Newsgroups, To, CC, ...).
8557
8558 Completion in the Newsgroups header depends on the list of groups
8559 known to your news reader. Completion in the Followup-To header
8560 offers those groups which are in the Newsgroups header, since
8561 Followup-To usually just holds one of those.
8562
8563 Completion in fields that hold mail addresses works based on the list
8564 of local users plus your aliases. Additionally, if your site provides
8565 a mail directory or a specific host to use for any unrecognized user
8566 name, you can arrange to query that host for completion also. (See the
8567 documentation of variables `mail-directory-process' and
8568 `mail-directory-stream'.)
8569
8570 ** A greatly extended sgml-mode offers new features such as (to be configured)
8571 skeletons with completing read for tags and attributes, typing named
8572 characters including optionally all 8bit characters, making tags invisible
8573 with optional alternate display text, skipping and deleting tag(pair)s.
8574
8575 Note: since Emacs' syntax feature cannot limit the special meaning of ', " and
8576 - to inside <>, for some texts the result, especially of font locking, may be
8577 wrong (see `sgml-specials' if you get wrong results).
8578
8579 The derived html-mode configures this with tags and attributes more or
8580 less HTML3ish. It also offers optional quick keys like C-c 1 for
8581 headline or C-c u for unordered list (see `html-quick-keys'). Edit /
8582 Text Properties / Face or M-g combinations create tags as applicable.
8583 Outline minor mode is supported and level 1 font-locking tries to
8584 fontify tag contents (which only works when they fit on one line, due
8585 to a limitation in font-lock).
8586
8587 External viewing via browse-url can occur automatically upon saving.
8588
8589 ** M-x imenu-add-to-menubar now adds to the menu bar for the current
8590 buffer only. If you want to put an Imenu item in the menu bar for all
8591 buffers that use a particular major mode, use the mode hook, as in
8592 this example:
8593
8594 (add-hook 'emacs-lisp-mode-hook
8595 '(lambda () (imenu-add-to-menubar "Index")))
8596
8597 ** Changes in BibTeX mode.
8598
8599 *** Field names may now contain digits, hyphens, and underscores.
8600
8601 *** Font Lock mode is now supported.
8602
8603 *** bibtex-make-optional-field is no longer interactive.
8604
8605 *** If bibtex-maintain-sorted-entries is non-nil, inserting new
8606 entries is now done with a faster algorithm. However, inserting
8607 will fail in this case if the buffer contains invalid entries or
8608 isn't in sorted order, so you should finish each entry with C-c C-c
8609 (bibtex-close-entry) after you have inserted or modified it.
8610 The default value of bibtex-maintain-sorted-entries is nil.
8611
8612 *** Function `show-all' is no longer bound to a key, since C-u C-c C-q
8613 does the same job.
8614
8615 *** Entries with quotes inside quote-delimited fields (as `author =
8616 "Stefan Sch{\"o}f"') are now supported.
8617
8618 *** Case in field names doesn't matter anymore when searching for help
8619 text.
8620
8621 ** Font Lock mode
8622
8623 *** Global Font Lock mode
8624
8625 Font Lock mode can be turned on globally, in buffers that support it, by the
8626 new command global-font-lock-mode. You can use the new variable
8627 font-lock-global-modes to control which modes have Font Lock mode automagically
8628 turned on. By default, this variable is set so that Font Lock mode is turned
8629 on globally where the buffer mode supports it.
8630
8631 For example, to automagically turn on Font Lock mode where supported, put:
8632
8633 (global-font-lock-mode t)
8634
8635 in your ~/.emacs.
8636
8637 *** Local Refontification
8638
8639 In Font Lock mode, editing a line automatically refontifies that line only.
8640 However, if your change alters the syntactic context for following lines,
8641 those lines remain incorrectly fontified. To refontify them, use the new
8642 command M-g M-g (font-lock-fontify-block).
8643
8644 In certain major modes, M-g M-g refontifies the entire current function.
8645 (The variable font-lock-mark-block-function controls how to find the
8646 current function.) In other major modes, M-g M-g refontifies 16 lines
8647 above and below point.
8648
8649 With a prefix argument N, M-g M-g refontifies N lines above and below point.
8650
8651 ** Follow mode
8652
8653 Follow mode is a new minor mode combining windows showing the same
8654 buffer into one tall "virtual window". The windows are typically two
8655 side-by-side windows. Follow mode makes them scroll together as if
8656 they were a unit. To use it, go to a frame with just one window,
8657 split it into two side-by-side windows using C-x 3, and then type M-x
8658 follow-mode.
8659
8660 M-x follow-mode turns off Follow mode if it is already enabled.
8661
8662 To display two side-by-side windows and activate Follow mode, use the
8663 command M-x follow-delete-other-windows-and-split.
8664
8665 ** hide-show changes.
8666
8667 The hooks hs-hide-hooks and hs-show-hooks have been renamed
8668 to hs-hide-hook and hs-show-hook, to follow the convention for
8669 normal hooks.
8670
8671 ** Simula mode now has a menu containing the most important commands.
8672 The new command simula-indent-exp is bound to C-M-q.
8673
8674 ** etags can now handle programs written in Erlang. Files are
8675 recognised by the extensions .erl and .hrl. The tagged lines are
8676 those that begin a function, record, or macro.
8677
8678 ** MSDOS Changes
8679
8680 *** It is now possible to compile Emacs with the version 2 of DJGPP.
8681 Compilation with DJGPP version 1 also still works.
8682
8683 *** The documentation of DOS-specific aspects of Emacs was rewritten
8684 and expanded; see the ``MS-DOS'' node in the on-line docs.
8685
8686 *** Emacs now uses ~ for backup file names, not .bak.
8687
8688 *** You can simulate mouse-3 on two-button mice by simultaneously
8689 pressing both mouse buttons.
8690
8691 *** A number of packages and commands which previously failed or had
8692 restricted functionality on MS-DOS, now work. The most important ones
8693 are:
8694
8695 **** Printing (both with `M-x lpr-buffer' and with `ps-print' package)
8696 now works.
8697
8698 **** `Ediff' works (in a single-frame mode).
8699
8700 **** `M-x display-time' can be used on MS-DOS (due to the new
8701 implementation of Emacs timers, see below).
8702
8703 **** `Dired' supports Unix-style shell wildcards.
8704
8705 **** The `c-macro-expand' command now works as on other platforms.
8706
8707 **** `M-x recover-session' works.
8708
8709 **** `M-x list-colors-display' displays all the available colors.
8710
8711 **** The `TPU-EDT' package works.
8712 \f
8713 * Lisp changes in Emacs 19.31.
8714
8715 ** The function using-unix-filesystems on Windows NT and Windows 95
8716 tells Emacs to read and write files assuming that they reside on a
8717 remote Unix filesystem. No CR/LF translation is done on any files in
8718 this case. Invoking using-unix-filesystems with t activates this
8719 behavior, and invoking it with any other value deactivates it.
8720
8721 ** Change in system-type and system-configuration values.
8722
8723 The value of system-type on a Linux-based GNU system is now `lignux',
8724 not `linux'. This means that some programs which use `system-type'
8725 need to be changed. The value of `system-configuration' will also
8726 be different.
8727
8728 It is generally recommended to use `system-configuration' rather
8729 than `system-type'.
8730
8731 See the file LINUX-GNU in this directory for more about this.
8732
8733 ** The functions shell-command and dired-call-process
8734 now run file name handlers for default-directory, if it has them.
8735
8736 ** Undoing the deletion of text now restores the positions of markers
8737 that pointed into or next to the deleted text.
8738
8739 ** Timers created with run-at-time now work internally to Emacs, and
8740 no longer use a separate process. Therefore, they now work more
8741 reliably and can be used for shorter time delays.
8742
8743 The new function run-with-timer is a convenient way to set up a timer
8744 to run a specified amount of time after the present. A call looks
8745 like this:
8746
8747 (run-with-timer SECS REPEAT FUNCTION ARGS...)
8748
8749 SECS says how many seconds should elapse before the timer happens.
8750 It may be an integer or a floating point number. When the timer
8751 becomes ripe, the action is to call FUNCTION with arguments ARGS.
8752
8753 REPEAT gives the interval for repeating the timer (measured in
8754 seconds). It may be an integer or a floating point number. nil or 0
8755 means don't repeat at all--call FUNCTION just once.
8756
8757 *** with-timeout provides an easy way to do something but give
8758 up if too much time passes.
8759
8760 (with-timeout (SECONDS TIMEOUT-FORMS...) BODY...)
8761
8762 This executes BODY, but gives up after SECONDS seconds.
8763 If it gives up, it runs the TIMEOUT-FORMS and returns the value
8764 of the last one of them. Normally it returns the value of the last
8765 form in BODY.
8766
8767 *** You can now arrange to call a function whenever Emacs is idle for
8768 a certain length of time. To do this, call run-with-idle-timer. A
8769 call looks like this:
8770
8771 (run-with-idle-timer SECS REPEAT FUNCTION ARGS...)
8772
8773 SECS says how many seconds of idleness should elapse before the timer
8774 runs. It may be an integer or a floating point number. When the
8775 timer becomes ripe, the action is to call FUNCTION with arguments
8776 ARGS.
8777
8778 Emacs becomes idle whenever it finishes executing a keyboard or mouse
8779 command. It remains idle until it receives another keyboard or mouse
8780 command.
8781
8782 REPEAT, if non-nil, means this timer should be activated again each
8783 time Emacs becomes idle and remains idle for SECS seconds The timer
8784 does not repeat if Emacs *remains* idle; it runs at most once after
8785 each time Emacs becomes idle.
8786
8787 If REPEAT is nil, the timer runs just once, the first time Emacs is
8788 idle for SECS seconds.
8789
8790 *** post-command-idle-hook is now obsolete; you shouldn't use it at
8791 all, because it interferes with the idle timer mechanism. If your
8792 programs use post-command-idle-hook, convert them to use idle timers
8793 instead.
8794
8795 *** y-or-n-p-with-timeout lets you ask a question but give up if
8796 there is no answer within a certain time.
8797
8798 (y-or-n-p-with-timeout PROMPT SECONDS DEFAULT-VALUE)
8799
8800 asks the question PROMPT (just like y-or-n-p). If the user answers
8801 within SECONDS seconds, it returns the answer that the user gave.
8802 Otherwise it gives up after SECONDS seconds, and returns DEFAULT-VALUE.
8803
8804 ** Minor change to `encode-time': you can now pass more than seven
8805 arguments. If you do that, the first six arguments have the usual
8806 meaning, the last argument is interpreted as the time zone, and the
8807 arguments in between are ignored.
8808
8809 This means that it works to use the list returned by `decode-time' as
8810 the list of arguments for `encode-time'.
8811
8812 ** The default value of load-path now includes the directory
8813 /usr/local/share/emacs/VERSION/site-lisp In addition to
8814 /usr/local/share/emacs/site-lisp. You can use this new directory for
8815 site-specific Lisp packages that belong with a particular Emacs
8816 version.
8817
8818 It is not unusual for a Lisp package that works well in one Emacs
8819 version to cause trouble in another. Sometimes packages need updating
8820 for incompatible changes; sometimes they look at internal data that
8821 has changed; sometimes the package has been installed in Emacs itself
8822 and the installed version should be used. Whatever the reason for the
8823 problem, this new feature makes it easier to solve.
8824
8825 ** When your program contains a fixed file name (like .completions or
8826 .abbrev.defs), the file name usually needs to be different on operating
8827 systems with limited file name syntax.
8828
8829 Now you can avoid ad-hoc conditionals by using the function
8830 convert-standard-filename to convert the file name to a proper form
8831 for each operating system. Here is an example of use, from the file
8832 completions.el:
8833
8834 (defvar save-completions-file-name
8835 (convert-standard-filename "~/.completions")
8836 "*The filename to save completions to.")
8837
8838 This sets the variable save-completions-file-name to a value that
8839 depends on the operating system, because the definition of
8840 convert-standard-filename depends on the operating system. On
8841 Unix-like systems, it returns the specified file name unchanged. On
8842 MS-DOS, it adapts the name to fit the limitations of that system.
8843
8844 ** The interactive spec N now returns the numeric prefix argument
8845 rather than the raw prefix argument. (It still reads a number using the
8846 minibuffer if there is no prefix argument at all.)
8847
8848 ** When a process is deleted, this no longer disconnects the process
8849 marker from its buffer position.
8850
8851 ** The variable garbage-collection-messages now controls whether
8852 Emacs displays a message at the beginning and end of garbage collection.
8853 The default is nil, meaning there are no messages.
8854
8855 ** The variable debug-ignored-errors specifies certain kinds of errors
8856 that should not enter the debugger. Its value is a list of error
8857 condition symbols and/or regular expressions. If the error has any
8858 of the condition symbols listed, or if any of the regular expressions
8859 matches the error message, then that error does not enter the debugger,
8860 regardless of the value of debug-on-error.
8861
8862 This variable is initialized to match certain common but uninteresting
8863 errors that happen often during editing.
8864
8865 ** The new function error-message-string converts an error datum
8866 into its error message. The error datum is what condition-case
8867 puts into the variable, to describe the error that happened.
8868
8869 ** Anything that changes which buffer appears in a given window
8870 now runs the window-scroll-functions for that window.
8871
8872 ** The new function get-buffer-window-list returns a list of windows displaying
8873 a buffer. The function is called with the buffer (a buffer object or a buffer
8874 name) and two optional arguments specifying the minibuffer windows and frames
8875 to search. Therefore this function takes optional args like next-window etc.,
8876 and not get-buffer-window.
8877
8878 ** buffer-substring now runs the hook buffer-access-fontify-functions,
8879 calling each function with two arguments--the range of the buffer
8880 being accessed. buffer-substring-no-properties does not call them.
8881
8882 If you use this feature, you should set the variable
8883 buffer-access-fontified-property to a non-nil symbol, which is a
8884 property name. Then, if all the characters in the buffer range have a
8885 non-nil value for that property, the buffer-access-fontify-functions
8886 are not called. When called, these functions should put a non-nil
8887 property on the text that they fontify, so that they won't get called
8888 over and over for the same text.
8889
8890 ** Changes in lisp-mnt.el
8891
8892 *** The lisp-mnt package can now recognize file headers that are written
8893 in the formats used by the `what' command and the RCS `ident' command:
8894
8895 ;; @(#) HEADER: text
8896 ;; $HEADER: text $
8897
8898 in addition to the normal
8899
8900 ;; HEADER: text
8901
8902 *** The commands lm-verify and lm-synopsis are now interactive. lm-verify
8903 checks that the library file has proper sections and headers, and
8904 lm-synopsis extracts first line "synopsis'"information.
8905
8906
8907 \f
8908 * For older news, see the file ONEWS
8909
8910 ----------------------------------------------------------------------
8911 Copyright information:
8912
8913 Copyright (C) 1999, 2000 Free Software Foundation, Inc.
8914
8915 Permission is granted to anyone to make or distribute verbatim copies
8916 of this document as received, in any medium, provided that the
8917 copyright notice and this permission notice are preserved,
8918 thus giving the recipient permission to redistribute in turn.
8919
8920 Permission is granted to distribute modified versions
8921 of this document, or of portions of it,
8922 under the above conditions, provided also that they
8923 carry prominent notices stating who last changed them.
8924 \f
8925 Local variables:
8926 mode: outline
8927 paragraph-separate: "[ \f]*$"
8928 end: