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