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