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1GNU Emacs NEWS -- history of user-visible changes. 23 Jan 1999
2Copyright (C) 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
3See the end for copying conditions.
4
5Please send Emacs bug reports to bug-gnu-emacs@gnu.org.
6For older news, see the file ONEWS.
7
8\f
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9* Installation Changes in Emacs 21.1
10
11** `movemail' defaults to supporting POP. You can turn this off using
12the --without-pop configure option, should that be necessary.
13\f
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14* Changes in Emacs 21.1
15
16** Faces and frame parameters.
17
18There are four new faces `scroll-bar', `border', `cursor' and `mouse'.
19Setting the frame parameters `scroll-bar-foreground' and
20`scroll-bar-background' sets foreground and background color of face
21`scroll-bar' and vice versa. Setting frame parameter `border-color'
22sets the background color of face `border' and vice versa. Likewise
23for frame parameters `cursor-color' and face `cursor', and frame
24parameter `mouse-color' and face `mouse'.
25
26Changing frame parameter `font' sets font-related attributes of the
27`default' face and vice versa. Setting frame parameters
28`foreground-color' or `background-color' sets the colors of the
29`default' face and vice versa.
30
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31** New face `menu'.
32
33The face `menu' can be used to change colors and font of Emacs' menus.
34Setting the font of LessTif/Motif menus is currently not supported;
35attempts to set the font are ignored in this case.
36
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37** New frame parameter `screen-gamma' for gamma correction.
38
39The new frame parameter `screen-gamma' specifies gamma-correction for
40colors. Its value may be nil, the default, in which case no gamma
41correction occurs, or a number > 0, usually a float, that specifies
42the screen gamma of a frame's display.
43
44PC monitors usually have a screen gamma of 2.2. smaller values result
45in darker colors. You might want to try a screen gamma of 1.5 for LCD
46color displays. The viewing gamma Emacs uses is 0.4545. (1/2.2).
47
48The X resource name of this parameter is `screenGamma', class
49`ScreenGamma'.
50
51** Emacs has a new redisplay engine.
52
53The new redisplay handles characters of variable width and height.
54Italic text can be used without redisplay problems. Fonts containing
55oversized characters, i.e. characters larger than the logical height
56of a font can be used. Images of various formats can be displayed in
57the text.
58
59** Emacs has a new face implementation.
60
61The new faces no longer fundamentally use X font names to specify the
62font. Instead, each face has several independent attributes--family,
63height, width, weight and slant--that it may or may not specify.
64These attributes can be merged from various faces, and then together
65specify a font.
66
67Faces are supported on terminals that can display color or fonts.
68These terminal capabilities are auto-detected. Details can be found
69under Lisp changes, below.
70
71** New default font is Courier 12pt.
72
73** When using a windowing terminal, Emacs window now has a cursor of
74its own. When the window is selected, the cursor is solid; otherwise,
75it is hollow.
76
77** Bitmap areas to the left and right of windows are used to display
78truncation marks, continuation marks, overlay arrows and alike. The
79foreground, background, and stipple of these areas can be changed by
80customizing face `fringe'.
81
82** The mode line under X is now drawn with shadows by default. You
83can change its appearance by modifying the face `modeline'.
84
85** LessTif support.
86
87Emacs now runs with LessTif (see <http://www.lesstif.org>). You will
88need a version 0.88.1 or later.
89
90** Toolkit scroll bars.
91
92Emacs now uses toolkit scrollbars if available. When configured for
93LessTif/Motif, it will use that toolkit's scrollbar. Otherwise, when
94configured for Lucid and Athena widgets, it will use the Xaw3d scroll
95bar if Xaw3d is available. You can turn off the use of toolkit scroll
96bars by specifying `--with-toolkit-scroll-bars=no' when configuring
97Emacs.
98
99When you encounter problems with the Xaw3d scroll bar, watch out how
100Xaw3d is compiled on your system. If the Makefile generated from
101Xaw3d's Imakefile contains a `-DNARROWPROTO' compiler option, and your
102Emacs system configuration file `s/your-system.h' does not contain a
103define for NARROWPROTO, you might consider adding it. Take
104`s/freebsd.h' as an example.
105
106Alternatively, if you don't have access to the Xaw3d source code, take
107a look at your system's imake configuration file, for example in the
108directory `/usr/X11R6/lib/X11/config' (paths are different on
109different systems). You will find files `*.cf' there. If your
110system's cf-file contains a line like `#define NeedWidePrototypes NO',
111add a `#define NARROWPROTO' to your Emacs system configuration file.
112
113The reason for this is that one Xaw3d function uses `double' or
114`float' function parameters depending on the setting of NARROWPROTO.
115This is not a problem when Imakefiles are used because each system's
116image configuration file contains the necessary information. Since
117Emacs doesn't use imake, this has do be done manually.
118
119** Toggle buttons and radio buttons in menus.
120
121When compiled with LessTif (or Motif) support, Emacs uses toolkit
122widgets for radio and toggle buttons in menus. When configured for
123Lucid, Emacs draws radio buttons and toggle buttons similar to Motif.
124
125** Highlighting of trailing whitespace.
126
127When `show-trailing-whitespace' is non-nil, Emacs displays trailing
128whitespace in the face `trailing-whitespace'. Trailing whitespace is
129defined as spaces or tabs at the end of a line. To avoid busy
130highlighting when entering new text, trailing whitespace is not
131displayed if point is at the end of the line containing the
132whitespace.
133
134** Busy-cursor.
135
136Emacs can optionally display a busy-cursor under X. You can turn the
137display on or off by customizing group `cursor'.
138
139** Blinking cursor
140
141M-x blink-cursor-mode toggles a blinking cursor under X and on
142terminals having terminal capabilities `vi', `vs', and `ve'. Blinking
143and related parameters like frequency and delay can be customized in
144the group `cursor'.
145
146** New font-lock support mode `jit-lock-mode'.
147
148This support mode is roughly equivalent to `lazy-lock' but is
149generally faster. It supports stealth and deferred fontification.
150See the documentation of the function `jit-lock-mode' for more
151details.
152
153Font-lock uses jit-lock-mode as default support mode, so you don't
154have to do anything to activate it.
155
156** Tabs and variable-width text.
157
158Tabs are now displayed with stretch properties; the width of a tab is
159defined as a multiple of the normal character width of a frame, and is
160independent of the fonts used in the text where the tab appears.
161Thus, tabs can be used to line up text in different fonts.
162
163** Enhancements of the Lucid menu bar
164
165*** The Lucid menu bar now supports the resource "margin".
166
167 emacs.pane.menubar.margin: 5
168
169The default margin is 4 which makes the menu bar appear like the Motif
170one.
171
172*** Arrows that indicate sub-menus are now drawn with shadows, like in
173Motif.
174
175** Hscrolling in C code.
176
177Horizontal scrolling now happens automatically.
178
179** Tool bar support.
180
181Emacs supports a tool bar at the top of a frame under X. For details
182how to define a tool bar, see the page describing Lisp-level changes.
183
184** Mouse-sensitive mode line.
185
186Different parts of the mode line under X have been made
187mouse-sensitive. Moving the mouse to a mouse-sensitive part in the mode
188line changes the appearance of the mouse pointer to an arrow, and help
189about available mouse actions is displayed either in the echo area, or
190in the tooltip window if you have enabled one.
191
192Currently, the following actions have been defined:
193
194- Mouse-1 on the buffer name in the mode line switches between two
195buffers.
196
197- Mouse-2 on the buffer-name switches to the next buffer, and
198M-mouse-2 switches to the previous buffer in the buffer list.
199
200- Mouse-3 on the buffer-name displays a buffer menu.
201
202- Mouse-1 on the read-only status in the mode line (`%' or `*')
203toggles the read-only status.
204
205- Mouse-3 on the mode name display a minor-mode menu.
206
207** LessTif/Motif file selection dialog.
208
209When Emacs is configured to use LessTif or Motif, reading a file name
210from a menu will pop up a file selection dialog if `use-dialogs' is
211non-nil.
212
213** Emacs can display faces on TTY frames.
214
215Emacs automatically detects terminals that are able to display colors.
216Faces with a weight greater than normal are displayed extra-bright, if
217the terminal supports it. Faces with a weight less than normal and
218italic faces are displayed dimmed, if the terminal supports it.
219Underlined faces are displayed underlined if possible. Other face
220attributes like overlines, strike-throught, box are ignored.
221
222** Sound support
223
224Emacs supports playing sound files on GNU/Linux and the free BSDs
225(Voxware driver and native BSD driver, aka as Luigi's driver).
226Currently supported file formats are RIFF-WAVE (*.wav) and Sun Audio
227(*.au). You must configure Emacs with the option `--with-sound=yes'
228to enable sound support.
229
230** A new variable, backup-by-copying-when-privileged-mismatch, gives
231the highest file uid for which backup-by-copying-when-mismatch will be
232forced on. The assumption is that uids less than or equal to this
233value are special uids (root, bin, daemon, etc.--not real system
234users) and that files owned by these users should not change ownership,
235even if your system policy allows users other than root to edit them.
236
237The default is 200; set the variable to nil to disable the feature.
238
239** A block cursor can be drawn as wide as the glyph under it under X.
240
241As an example: if a block cursor is over a tab character, it will be
242drawn as wide as that tab on the display. To do this, set
243`x-stretch-cursor' to a non-nil value.
244
245** Empty display lines at the end of a buffer may be marked with a
246bitmap (this is similar to the tilde displayed by vi).
247
248This behavior is activated by setting the buffer-local variable
249`indicate-empty-lines' to a non-nil value. The default value of this
250variable is found in `default-indicate-empty-lines'.
251
252** There is a new "aggressive" scrolling method.
253
254When scrolling up because point is above the window start, if the
255value of the buffer-local variable `scroll-up-aggessively' is a
256number, Emacs chooses a new window start so that point ends up that
257fraction of the window's height from the bottom of the window.
258
259When scrolling down because point is below the window end, if the
260value of the buffer-local variable `scroll-down-aggessively' is a
261number, Emacs chooses a new window start so that point ends up that
262fraction of the window's height from the top of the window.
263
264** The rectangle commands now avoid inserting undesirable spaces,
265notably at the end of lines.
266
267All these functions have been rewritten to avoid inserting unwanted
268spaces, and an optional prefix now allows them to behave the old way.
269
270** The new command M-x query-replace-regexp-eval acts like
271query-replace-regexp, but takes a Lisp expression which is evaluated
272after each match to get the replacement text.
273
274** Emacs now resizes mini-windows if appropriate.
275
276If a message is longer than one line, or mini-buffer contents are
277longer than one line, Emacs now resizes the mini-window unless it is
278on a frame of its own. You can control the maximum mini-window size
279by setting the following variable:
280
281- User option: max-mini-window-height
282
283Maximum height for resizing mini-windows. If a float, it specifies a
284fraction of the mini-window frame's height. If an integer, it
285specifies a number of lines. If nil, don't resize.
286
287Default is 0.25.
288
289** Changes to RefTeX mode
290
291*** RefTeX has new support for index generation. Index entries can be
292 created with `C-c <', with completion available on index keys.
293 Pressing `C-c /' indexes the word at the cursor with a default
294 macro. `C-c >' compiles all index entries into an alphabetically
295 sorted *Index* buffer which looks like the final index. Entries
296 can be edited from that buffer.
297
298*** Label and citation key selection now allow to select several
299 items and reference them together (use `m' to mark items, `a' or
300 `A' to use all marked entries).
301
302*** reftex.el has been split into a number of smaller files to reduce
303 memory use when only a part of RefTeX is being used.
304
305*** a new command `reftex-view-crossref-from-bibtex' (bound to `C-c &'
306 in BibTeX-mode) can be called in a BibTeX database buffer in order
307 to show locations in LaTeX documents where a particular entry has
308 been cited.
309
310** The M-x time-stamp command (most commonly used on write-file-hooks)
311has the following new features:
312
313*** The patterns for finding the time stamp and for updating a pattern
314may match text spanning multiple lines. For example, some people like
315to have the filename and date on separate lines. The new variable
316time-stamp-inserts-lines controls the matching for multi-line patterns.
317
318*** More than one time stamp can be updated in the same file. This
319feature is useful if you need separate time stamps in a program source
320file to both include in formatted documentation and insert in the
321compiled binary. The same time-stamp will be written at each matching
322pattern. The variable time-stamp-count enables this new feature; it
323defaults to 1.
324
325** Tooltips.
326
327Tooltips are small X windows displaying a help string at the current
328mouse position. To use them, use the Lisp package `tooltip' which you
329can access via the user option `tooltip-mode'.
330
331Tooltips also provides support for GUD debugging. If activated,
332variable values can be displayed in tooltips by pointing at them with
333the mouse in source buffers. You can customize various aspects of the
334tooltip display in the group `tooltip'.
335
336** Customize changes
337
338*** Customize now supports comments about customized items. Use the
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339`State' menu to add comments. Note that customization comments will
340cause the customizations to fail in earlier versions of Emacs.
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341
342*** The new option `custom-buffer-done-function' says whether to kill
343Custom buffers when you've done with them or just bury them (the
344default).
345
346** New features in evaluation commands
347
348The commands to evaluate Lisp expressions, such as C-M-x in Lisp
349modes, C-j in Lisp Interaction mode, and M-:, now bind the variables
350print-level, print-length, and debug-on-error based on the
351customizable variables eval-expression-print-level,
352eval-expression-print-length, and eval-expression-debug-on-error.
353
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354** Dired changes
355
356*** New variable `dired-recursive-deletes' determines if the delete
357command will delete non-empty directories recursively. The default
358is, delete only empty directories.
359
360*** New variable `dired-recursive-copies' determines if the copy
361command will copy directories recursively. The default is, do not
362copy directories recursively.
363
364** The variable mail-specify-envelope-from controls whether to
365use the -f option when sending mail.
366
367** In Isearch mode, mouse-2 in the echo area now yanks the current
368selection into the search string rather than giving an error.
369
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370** Ange-ftp allows you to specify of a port number in remote file
371names cleanly. It is appended to the host name, separated by a hash
372sign, e.g. `/foo@bar.org#666:mumble'. (This syntax comes from EFS.)
373
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374** Shell script mode changes.
375
376Shell script mode (sh-script) can now indent scripts for shells
377derived from sh and rc. The indentation style is customizeable, and
378sh-script can attempt to "learn" the current buffer's style.
379
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380** Emacs now attempts to determine the initial language environment
381and preferred and locale coding systems systematically from the
382LC_ALL, LC_CTYPE, and LANG environment variables during startup.
383
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384** New language environments `Latin-8' and `Latin-9'.
385These correspond respectively to the ISO character sets 8859-14
386(Celtic) and 8859-15 (updated Latin-1, with the Euro sign). There is
387currently no specific input method support for them.
388
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389** New modes and packages
390
391*** 5x5.el is a simple puzzle game.
392
393*** hl-line.el provides a minor mode to highlight the current line.
394
395*** ansi-color.el translates ANSI terminal escapes into text-properties.
396
397*** delphi.el provides a major mode for editing the Delphi (Object
398Pascal) language.
399
400*** quickurl.el provides a simple method of inserting a URL based on
401the text at point.
402
403*** sql.el provides an interface to SQL data bases.
404
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405*** fortune.el uses the fortune program to create mail/news signatures.
406
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407*** whitespace.el ???
408
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409*** PostScript mode (ps-mode) is a new major mode for editing PostScript
410files. It offers: interaction with a PostScript interpreter, including
411(very basic) error handling; fontification, easily customizable for
412interpreter messages; auto-indentation; insertion of EPSF templates and
413often used code snippets; viewing of BoundingBox; commenting out /
414uncommenting regions; conversion of 8bit characters to PostScript octal
415codes. All functionality is accessible through a menu.
416
417*** delim-col helps to prettify columns in a text region or rectangle.
418
419Here is an example of columns:
420
421horse apple bus
422dog pineapple car EXTRA
423porcupine strawberry airplane
424
425Doing the following settings:
426
427 (setq delimit-columns-str-before "[ ")
428 (setq delimit-columns-str-after " ]")
429 (setq delimit-columns-str-separator ", ")
430 (setq delimit-columns-separator "\t")
431
432
433Selecting the lines above and typing:
434
435 M-x delimit-columns-region
436
437It results:
438
439[ horse , apple , bus , ]
440[ dog , pineapple , car , EXTRA ]
441[ porcupine, strawberry, airplane, ]
442
443delim-col has the following options:
444
445 delimit-columns-str-before Specify a string to be inserted
446 before all columns.
447
448 delimit-columns-str-separator Specify a string to be inserted
449 between each column.
450
451 delimit-columns-str-after Specify a string to be inserted
452 after all columns.
453
454 delimit-columns-separator Specify a regexp which separates
455 each column.
456
457delim-col has the following commands:
458
459 delimit-columns-region Prettify all columns in a text region.
460 delimit-columns-rectangle Prettify all columns in a text rectangle.
461
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462*** The package recentf.el maintains a menu for visiting files that
463were operated on recently. When enabled, a new "Open Recent" submenu
464is displayed in the "Files" menu.
465
466The recent files list is automatically saved across Emacs sessions.
467
468To enable/disable recentf use M-x recentf-mode.
469
470To enable recentf at Emacs startup use
471M-x customize-variable RET recentf-mode RET.
472
473To change the number of recent files displayed and others options use
474M-x customize-group RET recentf RET.
475
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476** Withdrawn packages
477
478*** mldrag.el has been removed. mouse.el provides the same
479functionality with aliases for the mldrag functions.
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480
481*** eval-reg.el has been obsoleted by changes to edebug.el.
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482
483** Not new, but not mentioned before:
484M-w when Transient Mark mode is enabled disables the mark.
485
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486\f
487* Lisp changes in Emacs 21.1 (see following page for display-related features)
488
489Note that +++ before an item means the Lisp manual has been updated.
490--- means that I have decided it does not need to be in the Lisp manual.
491When you add a new item, please add it without either +++ or ---
492so I will know I still need to look at it -- rms.
493
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494** New functions and variables for locales.
495
496The new variable `locale-coding-system' specifies how to encode and
497decode strings passed to low-level message functions like strerror and
498time functions like strftime. The new variables `messages-locale' and
499`time-locale' give the system locales to be used during the next
500invocations of these two types of functions; the new variables
501`previous-messages-locale' and `previous-time-locale' give the locales
502most recently used.
503
504The new function `set-locale-environment' sets the language
505environment, preferred coding system, and locale coding system from
506the system locale as specified by the LC_ALL, LC_CTYPE, and LANG
507environment variables. It is normally invoked during startup. It
508uses the new variables `locale-language-names',
509`locale-charset-language-names', and `locale-preferred-coding-systems'
510to make its decisions.
511
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512** syntax tables now understand nested comments.
513To declare a comment syntax as allowing nesting, just add an `n'
514modifier to either of the characters of the comment end and the comment
515start sequences.
516
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517** The function `pixmap-spec-p' has been renamed `bitmap-spec-p'
518because `bitmap' is more in line with the usual X terminology.
519
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520** New function `propertize'
521
522The new function `propertize' can be used to conveniently construct
523strings with text properties.
524
525- Function: propertize STRING &rest PROPERTIES
526
527Value is a copy of STRING with text properties assigned as specified
528by PROPERTIES. PROPERTIES is a sequence of pairs PROPERTY VALUE, with
529PROPERTY being the name of a text property and VALUE being the
530specified value of that property. Example:
531
532 (propertize "foo" 'face 'bold 'read-only t)
533
534+++
535** push and pop macros.
536
537A simple version of the push and pop macros of Common Lisp
538is now defined in Emacs Lisp. These macros allow only symbols
539as the place that holds the list to be changed.
540
541(push NEWELT LISTNAME) add NEWELT to the front of LISTNAME's value.
542(pop LISTNAME) return first elt of LISTNAME, and remove it
543 (thus altering the value of LISTNAME).
544
545+++
546** Regular expressions now support Posix character classes such
547as [:alpha:], [:space:] and so on.
548
549[:digit:] matches 0 through 9
550[:cntrl:] matches ASCII control characters
551[:xdigit:] matches 0 through 9, a through f and A through F.
552[:blank:] matches space and tab only
553[:graph:] matches graphic characters--everything except ASCII control chars,
554 space, and DEL.
555[:print:] matches printing characters--everything except ASCII control chars
556 and DEL.
557[:alnum:] matches letters and digits.
558 (But at present, for multibyte characters,
559 it matches anything that has word syntax.)
560[:alpha:] matches letters.
561 (But at present, for multibyte characters,
562 it matches anything that has word syntax.)
563[:ascii:] matches ASCII (unibyte) characters.
564[:nonascii:] matches non-ASCII (multibyte) characters.
565[:lower:] matches anything lower-case.
566[:punct:] matches punctuation.
567 (But at present, for multibyte characters,
568 it matches anything that has non-word syntax.)
569[:space:] matches anything that has whitespace syntax.
570[:upper:] matches anything upper-case.
571[:word:] matches anything that has word syntax.
572
573+++
574** Emacs now has built-in hash tables.
575
576The following functions are defined for hash tables:
577
578- Function: make-hash-table ARGS
579
580The argument list ARGS consists of keyword/argument pairs. All arguments
581are optional. The following arguments are defined:
582
583:test TEST
584
585TEST must be a symbol specifying how to compare keys. Default is `eql'.
586Predefined are `eq', `eql' and `equal'. If TEST is not predefined,
587it must have been defined with `define-hash-table-test'.
588
589:size SIZE
590
591SIZE must be an integer > 0 giving a hint to the implementation how
592many elements will be put in the hash table. Default size is 65.
593
594:rehash-size REHASH-SIZE
595
596REHASH-SIZE specifies by how much to grow a hash table once it becomes
597full. If REHASH-SIZE is an integer, add that to the hash table's old
598size to get the new size. Otherwise, REHASH-SIZE must be a float >
5991.0, and the new size is computed by multiplying REHASH-SIZE with the
600old size. Default rehash size is 1.5.
601
602:rehash-threshold THRESHOLD
603
604THRESHOLD must be a float > 0 and <= 1.0 specifying when to resize the
605hash table. It is resized when the ratio of (number of entries) /
606(size of hash table) is >= THRESHOLD. Default threshold is 0.8.
607
608:weakness WEAK
609
610WEAK must be either nil, one of the symbols `key, `value', or t.
611Entries are removed from weak tables during garbage collection if
612their key and/or value are not referenced elsewhere outside of the
613hash table. Default are non-weak hash tables.
614
615- Function: makehash &optional TEST
616
617Similar to make-hash-table, but only TEST can be specified.
618
619- Function: hash-table-p TABLE
620
621Returns non-nil if TABLE is a hash table object.
622
623- Function: copy-hash-table TABLE
624
625Returns a copy of TABLE. Only the table itself is copied, keys and
626values are shared.
627
628- Function: hash-table-count TABLE
629
630Returns the number of entries in TABLE.
631
632- Function: hash-table-rehash-size TABLE
633
634Returns the rehash size of TABLE.
635
636- Function: hash-table-rehash-threshold TABLE
637
638Returns the rehash threshold of TABLE.
639
640- Function: hash-table-rehash-size TABLE
641
642Returns the size of TABLE.
643
644- Function: hash-table-rehash-test TABLE
645
646Returns the test TABLE uses to compare keys.
647
648- Function: hash-table-weakness TABLE
649
650Returns the weakness specified for TABLE.
651
652- Function: clrhash TABLE
653
654Clear TABLE.
655
656- Function: gethash KEY TABLE &optional DEFAULT
657
658Look up KEY in TABLE and return its associated VALUE or DEFAULT if
659not found.
660
661- Function: puthash KEY VALUE TABLE
662
663Associate KEY with VALUE in TABLE. If KEY is already associated with
664another value, replace the old value with VALUE.
665
666- Function: remhash KEY TABLE
667
668Remove KEY from TABLE if it is there.
669
670- Function: maphash FUNCTION TABLE
671
672Call FUNCTION for all elements in TABLE. FUNCTION must take two
673arguments KEY and VALUE.
674
675- Function: sxhash OBJ
676
677Return a hash code for Lisp object OBJ.
678
679- Function: define-hash-table-test NAME TEST-FN HASH-FN
680
681Define a new hash table test named NAME. If NAME is specified as
682a test in `make-hash-table', the table created will use TEST-FN for
683comparing keys, and HASH-FN to compute hash codes for keys. Test
684and hash function are stored as symbol property `hash-table-test'
685of NAME with a value of (TEST-FN HASH-FN).
686
687TEST-FN must take two arguments and return non-nil if they are the same.
688
689HASH-FN must take one argument and return an integer that is the hash
690code of the argument. The function should use the whole range of
691integer values for hash code computation, including negative integers.
692
693Example: The following creates a hash table whose keys are supposed to
694be strings that are compared case-insensitively.
695
696 (defun case-fold-string= (a b)
697 (compare-strings a nil nil b nil nil t))
698
699 (defun case-fold-string-hash (a)
700 (sxhash (upcase a)))
701
702 (define-hash-table-test 'case-fold 'case-fold-string=
703 'case-fold-string-hash))
704
705 (make-hash-table :test 'case-fold)
706
707+++
708** The Lisp reader handles circular structure.
709
710It now works to use the #N= and #N# constructs to represent
711circular structures. For example, #1=(a . #1#) represents
712a cons cell which is its own cdr.
713
714+++
715** The Lisp printer handles circular structure.
716
717If you bind print-circle to a non-nil value, the Lisp printer outputs
718#N= and #N# constructs to represent circular and shared structure.
719
720You can also do several calls to print functions using a common
721set of #N= constructs; here is how.
722
723 (let ((print-circle t)
724 (print-continuous-numbering t)
725 print-number-table)
726 (print1 ...)
727 (print1 ...)
728 ...)
729
730+++
731** If the second argument to `move-to-column' is anything but nil or
732t, that means replace a tab with spaces if necessary to reach the
733specified column, but do not add spaces at the end of the line if it
734is too short to reach that column.
735
736+++
737** perform-replace has a new feature: the REPLACEMENTS argument may
738now be a cons cell (FUNCTION . DATA). This means to call FUNCTION
739after each match to get the replacement text. FUNCTION is called with
740two arguments: DATA, and the number of replacements already made.
741
742If the FROM-STRING contains any upper-case letters,
743perform-replace also turns off `case-fold-search' temporarily
744and inserts the replacement text without altering case in it.
745
746+++
747** The function buffer-size now accepts an optional argument
748to specify which buffer to return the size of.
749
750+++
751** The calendar motion commands now run the normal hook
752calendar-move-hook after moving point.
753
754+++
755** The new variable small-temporary-file-directory specifies a
756directory to use for creating temporary files that are likely to be
757small. (Certain Emacs features use this directory.) If
758small-temporary-file-directory is nil, they use
759temporary-file-directory instead.
760
761+++
762** The variable `inhibit-modification-hooks', if non-nil, inhibits all
763the hooks that track changes in the buffer. This affects
764`before-change-functions' and `after-change-functions', as well as
765hooks attached to text properties and overlay properties.
766
767+++
768** assoc-delete-all is a new function that deletes all the
769elements of an alist which have a particular value as the car.
770
771+++
772** make-temp-file provides a more reliable way to create a temporary file.
773
774make-temp-file is used like make-temp-name, except that it actually
775creates the file before it returns. This prevents a timing error,
776ensuring that no other job can use the same name for a temporary file.
777
778+++
779** New exclusive-open feature in `write-region'
780
781The optional seventh arg is now called MUSTBENEW. If non-nil, it insists
782on a check for an existing file with the same name. If MUSTBENEW
783is `excl', that means to get an error if the file already exists;
784never overwrite. If MUSTBENEW is neither nil nor `excl', that means
785ask for confirmation before overwriting, but do go ahead and
786overwrite the file if the user gives confirmation.
787
788If the MUSTBENEW argument in `write-region' is `excl',
789that means to use a special feature in the `open' system call
790to get an error if the file exists at that time.
791The error reported is `file-already-exists'.
792
793+++
794** Function `format' now handles text properties.
795
796Text properties of the format string are applied to the result string.
797If the result string is longer than the format string, text properties
798ending at the end of the format string are extended to the end of the
799result string.
800
801Text properties from string arguments are applied to the result
802string where arguments appear in the result string.
803
804Example:
805
806 (let ((s1 "hello, %s")
807 (s2 "world"))
808 (put-text-property 0 (length s1) 'face 'bold s1)
809 (put-text-property 0 (length s2) 'face 'italic s2)
b246b1f6 810 (format s1 s2))
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811
812results in a bold-face string with an italic `world' at the end.
813
814+++
815** Messages can now be displayed with text properties.
816
817Text properties are handled as described above for function `format'.
818The following example displays a bold-face message with an italic
819argument in it.
820
821 (let ((msg "hello, %s!")
822 (arg "world"))
823 (put-text-property 0 (length msg) 'face 'bold msg)
824 (put-text-property 0 (length arg) 'face 'italic arg)
825 (message msg arg))
826
827+++
828** Sound support
829
830Emacs supports playing sound files on GNU/Linux and the free BSDs
831(Voxware driver and native BSD driver, aka as Luigi's driver).
832
833Currently supported file formats are RIFF-WAVE (*.wav) and Sun Audio
834(*.au). You must configure Emacs with the option `--with-sound=yes'
835to enable sound support.
836
837Sound files can be played by calling (play-sound SOUND). SOUND is a
838list of the form `(sound PROPERTY...)'. The function is only defined
839when sound support is present for the system on which Emacs runs. The
840functions runs `play-sound-functions' with one argument which is the
841sound to play, before playing the sound.
842
843The following sound properties are supported:
844
845- `:file FILE'
846
847FILE is a file name. If FILE isn't an absolute name, it will be
848searched relative to `data-directory'.
849
850- `:volume VOLUME'
851
852VOLUME must be an integer in the range 0..100 or a float in the range
8530..1. This property is optional.
854
855Other properties are ignored.
856
857** `multimedia' is a new Finder keyword and Custom group.
858\f
859* New Lisp-level Display features in Emacs 21.1
860
861Note that +++ before an item means the Lisp manual has been updated.
862--- means that I have decided it does not need to be in the Lisp manual.
863When you add a new item, please add it without either +++ or ---
864so I will know I still need to look at it -- rms.
865
866** New face implementation.
867
868Emacs faces have been reimplemented from scratch. They don't use XLFD
869font names anymore and face merging now works as expected.
870
871+++
872*** New faces.
873
874Each face can specify the following display attributes:
875
876 1. Font family or fontset alias name.
877
878 2. Relative proportionate width, aka character set width or set
879 width (swidth), e.g. `semi-compressed'.
880
881 3. Font height in 1/10pt
882
883 4. Font weight, e.g. `bold'.
884
885 5. Font slant, e.g. `italic'.
886
887 6. Foreground color.
888
889 7. Background color.
890
891 8. Whether or not characters should be underlined, and in what color.
892
893 9. Whether or not characters should be displayed in inverse video.
894
895 10. A background stipple, a bitmap.
896
897 11. Whether or not characters should be overlined, and in what color.
898
899 12. Whether or not characters should be strike-through, and in what
900 color.
901
902 13. Whether or not a box should be drawn around characters, its
903 color, the width of the box lines, and 3D appearance.
904
905Faces are frame-local by nature because Emacs allows to define the
906same named face (face names are symbols) differently for different
907frames. Each frame has an alist of face definitions for all named
908faces. The value of a named face in such an alist is a Lisp vector
909with the symbol `face' in slot 0, and a slot for each each of the face
910attributes mentioned above.
911
912There is also a global face alist `face-new-frame-defaults'. Face
913definitions from this list are used to initialize faces of newly
914created frames.
915
916A face doesn't have to specify all attributes. Those not specified
917have a nil value. Faces specifying all attributes are called
918`fully-specified'.
919
920+++
921*** Face merging.
922
923The display style of a given character in the text is determined by
924combining several faces. This process is called `face merging'. Any
925aspect of the display style that isn't specified by overlays or text
926properties is taken from the `default' face. Since it is made sure
927that the default face is always fully-specified, face merging always
928results in a fully-specified face.
929
930+++
931*** Face realization.
932
933After all face attributes for a character have been determined by
934merging faces of that character, that face is `realized'. The
935realization process maps face attributes to what is physically
936available on the system where Emacs runs. The result is a `realized
937face' in form of an internal structure which is stored in the face
938cache of the frame on which it was realized.
939
940Face realization is done in the context of the charset of the
941character to display because different fonts and encodings are used
942for different charsets. In other words, for characters of different
943charsets, different realized faces are needed to display them.
944
945Except for composite characters, faces are always realized for a
946specific character set and contain a specific font, even if the face
947being realized specifies a fontset. The reason is that the result of
948the new font selection stage is better than what can be done with
949statically defined font name patterns in fontsets.
950
951In unibyte text, Emacs' charsets aren't applicable; function
952`char-charset' reports ASCII for all characters, including those >
9530x7f. The X registry and encoding of fonts to use is determined from
954the variable `face-default-registry' in this case. The variable is
955initialized at Emacs startup time from the font the user specified for
956Emacs.
957
958Currently all unibyte text, i.e. all buffers with
959`enable-multibyte-characters' nil are displayed with fonts of the same
960registry and encoding `face-default-registry'. This is consistent
961with the fact that languages can also be set globally, only.
962
963++++
964**** Clearing face caches.
965
966The Lisp function `clear-face-cache' can be called to clear face caches
967on all frames. If called with a non-nil argument, it will also unload
968unused fonts.
969
970+++
971*** Font selection.
972
973Font selection tries to find the best available matching font for a
974given (charset, face) combination. This is done slightly differently
975for faces specifying a fontset, or a font family name.
976
977If the face specifies a fontset name, that fontset determines a
978pattern for fonts of the given charset. If the face specifies a font
979family, a font pattern is constructed. Charset symbols have a
980property `x-charset-registry' for that purpose that maps a charset to
981an XLFD registry and encoding in the font pattern constructed.
982
983Available fonts on the system on which Emacs runs are then matched
984against the font pattern. The result of font selection is the best
985match for the given face attributes in this font list.
986
987Font selection can be influenced by the user.
988
989The user can specify the relative importance he gives the face
990attributes width, height, weight, and slant by setting
991face-font-selection-order (faces.el) to a list of face attribute
992names. The default is (:width :height :weight :slant), and means
993that font selection first tries to find a good match for the font
994width specified by a face, then---within fonts with that width---tries
995to find a best match for the specified font height, etc.
996
997Setting `face-alternative-font-family-alist' allows the user to
998specify alternative font families to try if a family specified by a
999face doesn't exist.
1000
1001+++
1002**** Scalable fonts
1003
1004Emacs can make use of scalable fonts but doesn't do so by default,
1005since the use of too many or too big scalable fonts may crash XFree86
1006servers.
1007
1008To enable scalable font use, set the variable
b246b1f6 1009`scalable-fonts-allowed'. A value of nil, the default, means never use
a933dad1
DL
1010scalable fonts. A value of t means any scalable font may be used.
1011Otherwise, the value must be a list of regular expressions. A
1012scalable font may then be used if it matches a regular expression from
1013that list. Example:
1014
1015 (setq scalable-fonts-allowed '("muleindian-2$"))
1016
1017allows the use of scalable fonts with registry `muleindian-2'.
1018
1019+++
1020*** Functions and variables related to font selection.
1021
1022- Function: x-family-fonts &optional FAMILY FRAME
1023
1024Return a list of available fonts of family FAMILY on FRAME. If FAMILY
1025is omitted or nil, list all families. Otherwise, FAMILY must be a
1026string, possibly containing wildcards `?' and `*'.
1027
1028If FRAME is omitted or nil, use the selected frame. Each element of
1029the result is a vector [FAMILY WIDTH POINT-SIZE WEIGHT SLANT FIXED-P
1030FULL REGISTRY-AND-ENCODING]. FAMILY is the font family name.
1031POINT-SIZE is the size of the font in 1/10 pt. WIDTH, WEIGHT, and
1032SLANT are symbols describing the width, weight and slant of the font.
1033These symbols are the same as for face attributes. FIXED-P is non-nil
1034if the font is fixed-pitch. FULL is the full name of the font, and
1035REGISTRY-AND-ENCODING is a string giving the registry and encoding of
1036the font. The result list is sorted according to the current setting
1037of the face font sort order.
1038
1039- Function: x-font-family-list
1040
1041Return a list of available font families on FRAME. If FRAME is
1042omitted or nil, use the selected frame. Value is a list of conses
1043(FAMILY . FIXED-P) where FAMILY is a font family, and FIXED-P is
1044non-nil if fonts of that family are fixed-pitch.
1045
1046- Variable: font-list-limit
1047
1048Limit for font matching. If an integer > 0, font matching functions
1049won't load more than that number of fonts when searching for a
1050matching font. The default is currently 100.
1051
1052+++
1053*** Setting face attributes.
1054
1055For the most part, the new face implementation is interface-compatible
1056with the old one. Old face attribute related functions are now
1057implemented in terms of the new functions `set-face-attribute' and
1058`face-attribute'.
1059
1060Face attributes are identified by their names which are keyword
1061symbols. All attributes can be set to `unspecified'.
1062
1063The following attributes are recognized:
1064
1065`:family'
1066
1067VALUE must be a string specifying the font family, e.g. ``courier'',
1068or a fontset alias name. If a font family is specified, wild-cards `*'
1069and `?' are allowed.
1070
1071`:width'
1072
1073VALUE specifies the relative proportionate width of the font to use.
1074It must be one of the symbols `ultra-condensed', `extra-condensed',
1075`condensed', `semi-condensed', `normal', `semi-expanded', `expanded',
1076`extra-expanded', or `ultra-expanded'.
1077
1078`:height'
1079
1080VALUE must be an integer specifying the height of the font to use in
10811/10 pt.
1082
1083`:weight'
1084
1085VALUE specifies the weight of the font to use. It must be one of the
1086symbols `ultra-bold', `extra-bold', `bold', `semi-bold', `normal',
1087`semi-light', `light', `extra-light', `ultra-light'.
1088
1089`:slant'
1090
1091VALUE specifies the slant of the font to use. It must be one of the
1092symbols `italic', `oblique', `normal', `reverse-italic', or
1093`reverse-oblique'.
1094
1095`:foreground', `:background'
1096
1097VALUE must be a color name, a string.
1098
1099`:underline'
1100
1101VALUE specifies whether characters in FACE should be underlined. If
1102VALUE is t, underline with foreground color of the face. If VALUE is
1103a string, underline with that color. If VALUE is nil, explicitly
1104don't underline.
1105
1106`:overline'
1107
1108VALUE specifies whether characters in FACE should be overlined. If
1109VALUE is t, overline with foreground color of the face. If VALUE is a
1110string, overline with that color. If VALUE is nil, explicitly don't
1111overline.
1112
1113`:strike-through'
1114
1115VALUE specifies whether characters in FACE should be drawn with a line
1116striking through them. If VALUE is t, use the foreground color of the
1117face. If VALUE is a string, strike-through with that color. If VALUE
1118is nil, explicitly don't strike through.
1119
1120`:box'
1121
1122VALUE specifies whether characters in FACE should have a box drawn
1123around them. If VALUE is nil, explicitly don't draw boxes. If
1124VALUE is t, draw a box with lines of width 1 in the foreground color
1125of the face. If VALUE is a string, the string must be a color name,
1126and the box is drawn in that color with a line width of 1. Otherwise,
1127VALUE must be a property list of the form `(:line-width WIDTH
1128:color COLOR :style STYLE)'. If a keyword/value pair is missing from
1129the property list, a default value will be used for the value, as
1130specified below. WIDTH specifies the width of the lines to draw; it
1131defaults to 1. COLOR is the name of the color to draw in, default is
1132the foreground color of the face for simple boxes, and the background
1133color of the face for 3D boxes. STYLE specifies whether a 3D box
1134should be draw. If STYLE is `released-button', draw a box looking
1135like a released 3D button. If STYLE is `pressed-button' draw a box
1136that appears like a pressed button. If STYLE is nil, the default if
1137the property list doesn't contain a style specification, draw a 2D
1138box.
1139
1140`:inverse-video'
1141
1142VALUE specifies whether characters in FACE should be displayed in
1143inverse video. VALUE must be one of t or nil.
1144
1145`:stipple'
1146
1147If VALUE is a string, it must be the name of a file of pixmap data.
1148The directories listed in the `x-bitmap-file-path' variable are
1149searched. Alternatively, VALUE may be a list of the form (WIDTH
1150HEIGHT DATA) where WIDTH and HEIGHT are the size in pixels, and DATA
1151is a string containing the raw bits of the bitmap. VALUE nil means
1152explicitly don't use a stipple pattern.
1153
1154For convenience, attributes `:family', `:width', `:height', `:weight',
1155and `:slant' may also be set in one step from an X font name:
1156
1157`:font'
1158
1159Set font-related face attributes from VALUE. VALUE must be a valid
1160XLFD font name. If it is a font name pattern, the first matching font
1161is used--this is for compatibility with the behavior of previous
1162versions of Emacs.
1163
1164For compatibility with Emacs 20, keywords `:bold' and `:italic' can
1165be used to specify that a bold or italic font should be used. VALUE
1166must be t or nil in that case. A value of `unspecified' is not allowed."
1167
1168Please see also the documentation of `set-face-attribute' and
1169`defface'.
1170
1171*** Face attributes and X resources
1172
1173The following X resource names can be used to set face attributes
1174from X resources:
1175
1176 Face attribute X resource class
1177-----------------------------------------------------------------------
1178 :family attributeFamily . Face.AttributeFamily
1179 :width attributeWidth Face.AttributeWidth
1180 :height attributeHeight Face.AttributeHeight
1181 :weight attributeWeight Face.AttributeWeight
1182 :slant attributeSlant Face.AttributeSlant
1183 foreground attributeForeground Face.AttributeForeground
1184 :background attributeBackground . Face.AttributeBackground
1185 :overline attributeOverline Face.AttributeOverline
1186 :strike-through attributeStrikeThrough Face.AttributeStrikeThrough
1187 :box attributeBox Face.AttributeBox
1188 :underline attributeUnderline Face.AttributeUnderline
1189 :inverse-video attributeInverse Face.AttributeInverse
1190 :stipple attributeStipple Face.AttributeStipple
1191 or attributeBackgroundPixmap
1192 Face.AttributeBackgroundPixmap
1193 :font attributeFont Face.AttributeFont
1194 :bold attributeBold Face.AttributeBold
1195 :italic attributeItalic . Face.AttributeItalic
1196 :font attributeFont Face.AttributeFont
1197
1198+++
1199*** Text property `face'.
1200
1201The value of the `face' text property can now be a single face
1202specification or a list of such specifications. Each face
1203specification can be
1204
12051. A symbol or string naming a Lisp face.
1206
12072. A property list of the form (KEYWORD VALUE ...) where each
1208 KEYWORD is a face attribute name, and VALUE is an appropriate value
1209 for that attribute. Please see the doc string of `set-face-attribute'
1210 for face attribute names.
1211
12123. Conses of the form (FOREGROUND-COLOR . COLOR) or
1213 (BACKGROUND-COLOR . COLOR) where COLOR is a color name. This is
1214 for compatibility with previous Emacs versions.
1215
1216+++
1217** Support functions for colors on text-only terminals.
1218
1219The function `face-register-tty-color' can be used to define colors
1220for use on TTY frames. It maps a color name to a color number on the
1221terminal. Emacs defines a couple of default color mappings by
1222default. You can get defined colors with a call to
1223`tty-defined-colors'. The function `face-clear-tty-colors' can be
1224used to clear the mapping table.
1225
1226+++
1227** The minibuffer prompt is now actually inserted in the minibuffer.
a933dad1 1228
463cac2d 1229This makes it possible to scroll through the prompt, if you want to.
a933dad1
DL
1230
1231The function minubuffer-prompt-end returns the current position of the
1232end of the minibuffer prompt, if the minibuffer is current.
1233Otherwise, it returns zero.
1234
463cac2d
GM
1235** New `field' abstraction in buffers.
1236
1237There is now code to support an abstraction called `fields' in emacs
1238buffers. A field is a contiguous region of text with the same `field'
1239text-property.
1240
1241Certain functions, such as forward-word, forward-sentence,
1242forward-paragraph, beginning-of-line, etc., stop moving when they come
1243to the boundary between fields (beginning-of-line and end-of-line will
1244not let the point move past the field boundary, but other movement
1245commands continue into the next field if repeated).
1246
1247The new function constrain-to-field may be used to achieve similar
1248behavior; other new field functions include field-beginning, field-end,
1249erase-field, and field-string.
1250
1251Now that the minibuffer prompt is inserted into the minibuffer, it is in
1252a separate field from the user-input part of the buffer, so that many
1253editing commands treat the user's text separately from the prompt.
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1254
1255+++
1256** Image support.
1257
1258Emacs can now display images. Images are inserted into text by giving
1259strings or buffer text a `display' text property containing one of
1260(AREA IMAGE) or IMAGE. The display of the `display' property value
1261replaces the display of the characters having that property.
1262
1263If the property value has the form (AREA IMAGE), AREA must be one of
1264`(margin left-margin)', `(margin right-margin)' or `(margin nil)'. If
1265AREA is `(margin nil)', IMAGE will be displayed in the text area of a
1266window, otherwise it will be displayed in the left or right marginal
1267area.
1268
1269IMAGE is an image specification.
1270
1271*** Image specifications
1272
1273Image specifications are lists of the form `(image PROPS)' where PROPS
1274is a property list whose keys are keyword symbols. Each
1275specifications must contain a property `:type TYPE' with TYPE being a
1276symbol specifying the image type, e.g. `xbm'.
1277
1278The following is a list of properties all image types share.
1279
1280`:ascent ASCENT'
1281
1282ASCENT must be a number in the range 0..100, and specifies the percentage
1283of the image's height to use for its ascent. Default is 50.
1284
1285`:margin MARGIN'
1286
1287MARGIN must be a number >= 0 specifying how many pixels to put as
1288margin around the image. Default is 0.
1289
1290`:relief RELIEF'
1291
1292RELIEF is analogous to the `:relief' attribute of faces. Puts a relief
1293around an image.
1294
1295`:algorithm ALGO'
1296
1297Apply an image algorithm to the image before displaying it. ALGO must
1298be a symbol specifying the algorithm. Currently only `laplace' is
1299supported which applies a Laplace edge detection algorithm to an image
1300which is intended to display images "disabled."
1301
1302`:heuristic-mask BG'
1303
1304If BG is not nil, build a clipping mask for the image, so that the
1305background of a frame is visible behind the image. If BG is t,
1306determine the background color of the image by looking at the 4
1307corners of the image, assuming the most frequently occuring color from
1308the corners is the background color of the image. Otherwise, BG must
1309be a list `(RED GREEN BLUE)' specifying the color to assume for the
1310background of the image.
1311
1312`:file FILE'
1313
1314Load image from FILE. If FILE is not absolute after expanding it,
1315search for the image in `data-directory'. Some image types support
1316building images from data. When this is done, no `:file' property
1317may be present in the image specification.
1318
1319
1320*** Supported image types
1321
b246b1f6 1322**** XBM, image type `xbm'.
a933dad1
DL
1323
1324XBM images don't require an external library. Additional image
1325properties supported are
1326
1327`:foreground FG'
1328
1329FG must be a string specifying the image foreground color. Default
1330is the frame's foreground.
1331
1332`:background FG'
1333
1334BG must be a string specifying the image foreground color. Default is
1335the frame's background color.
1336
1337XBM images can be constructed from data instead of file. In this
1338case, the image specification must contain the following properties
1339instead of a `:file' property.
1340
1341`:width WIDTH'
1342
1343WIDTH specifies the width of the image in pixels.
1344
1345`:height HEIGHT'
1346
1347HEIGHT specifies the height of the image in pixels.
1348
1349`:data DATA'
1350
1351DATA must be either
1352
1353 1. a string large enough to hold the bitmap data, i.e. it must
1354 have a size >= (WIDTH + 7) / 8 * HEIGHT
1355
1356 2. a bool-vector of size >= WIDTH * HEIGHT
1357
1358 3. a vector of strings or bool-vectors, one for each line of the
1359 bitmap.
1360
1361**** XPM, image type `xpm'
1362
1363XPM images require the external library `libXpm', package
1364`xpm-3.4k.tar.gz', version 3.4k or later. Make sure the library is
1365found when Emacs is configured by supplying appropriate paths via
1366`--x-includes' and `--x-libraries'.
1367
1368Additional image properties supported are:
1369
1370`:color-symbols SYMBOLS'
1371
1372SYMBOLS must be a list of pairs (NAME . COLOR), with NAME being the
1373name of color as it appears in an XPM file, and COLOR being an X color
1374name.
1375
1376XPM images can be built from memory instead of files. In that case,
1377add a `:data' property instead of a `:file' property.
1378
1379`:data DATA'
1380
1381DATA must be a string containing an XPM image. The contents of the
1382string are of the same format as that of XPM files.
1383
1384The XPM library uses libz in its implementation so that it is able
1385to display compressed images.
1386
1387**** PBM, image type `pbm'
1388
1389PBM images don't require an external library. Color, gray-scale and
1390mono images are supported. There are no additional image properties
1391defined.
1392
1393**** JPEG, image type `jpeg'
1394
1395Support for JPEG images requires the external library `libjpeg',
1396package `jpegsrc.v6a.tar.gz', or later. There are no additional image
1397properties defined.
1398
1399**** TIFF, image type `tiff'
1400
1401Support for TIFF images requires the external library `libtiff',
1402package `tiff-v3.4-tar.gz', or later. There are no additional image
1403properties defined.
1404
1405**** GIF, image type `gif'
1406
1407Support for GIF images requires the external library `libungif', package
1408`libungif-4.1.0', or later.
1409
1410Additional image properties supported are:
1411
1412`:index INDEX'
1413
1414INDEX must be an integer >= 0. Load image number INDEX from a
1415multi-image GIF file. An error is signalled if INDEX is too large.
1416
1417This could be used to implement limited support for animated GIFs.
1418For example, the following function displays a multi-image GIF file
1419at point-min in the current buffer, switching between sub-images
1420every 0.1 seconds.
1421
1422(defun show-anim (file max)
1423 "Display multi-image GIF file FILE which contains MAX subimages."
1424 (display-anim (current-buffer) file 0 max t))
1425
1426(defun display-anim (buffer file idx max first-time)
1427 (when (= idx max)
1428 (setq idx 0))
1429 (let ((img (create-image file nil :index idx)))
1430 (save-excursion
1431 (set-buffer buffer)
1432 (goto-char (point-min))
1433 (unless first-time (delete-char 1))
1434 (insert-image img "x"))
1435 (run-with-timer 0.1 nil 'display-anim buffer file (1+ idx) max nil)))
1436
1437**** PNG, image type `png'
1438
1439Support for PNG images requires the external library `libpng',
1440package `libpng-1.0.2.tar.gz', or later. There are no additional image
1441properties defined.
1442
1443**** Ghostscript, image type `postscript'.
1444
1445Additional image properties supported are:
1446
1447`:pt-width WIDTH'
1448
1449WIDTH is width of the image in pt (1/72 inch). WIDTH must be an
b246b1f6 1450integer. This is a required property.
a933dad1
DL
1451
1452`:pt-height HEIGHT'
1453
1454HEIGHT specifies the height of the image in pt (1/72 inch). HEIGHT
b246b1f6 1455must be a integer. This is an required property.
a933dad1
DL
1456
1457`:bounding-box BOX'
1458
1459BOX must be a list or vector of 4 integers giving the bounding box of
1460the PS image, analogous to the `BoundingBox' comment found in PS
1461files. This is an required property.
1462
1463Part of the Ghostscript interface is implemented in Lisp. See
1464lisp/gs.el.
1465
1466*** Lisp interface.
1467
1468The variable `image-types' contains a list of those image types
1469which are supported in the current configuration.
1470
1471Images are stored in an image cache and removed from the cache when
1472they haven't been displayed for `image-cache-eviction-delay seconds.
1473The function `clear-image-cache' can be used to clear the image cache
1474manually.
1475
1476*** Simplified image API, image.el
1477
1478The new Lisp package image.el contains functions that simplify image
1479creation and putting images into text. The function `create-image'
1480can be used to create images. The macro `defimage' can be used to
1481define an image based on available image types. The functions
1482`put-image' and `insert-image' can be used to insert an image into a
1483buffer.
1484
1485+++
1486** Display margins.
1487
1488Windows can now have margins which are used for special text
1489and images.
1490
1491To give a window margins, either set the buffer-local variables
1492`left-margin-width' and `right-margin-width', or call
1493`set-window-margins'. The function `window-margins' can be used to
1494obtain the current settings. To make `left-margin-width' and
1495`right-margin-width' take effect, you must set them before displaying
1496the buffer in a window, or use `set-window-buffer' to force an update
1497of the display margins.
1498
1499You can put text in margins by giving it a `display' text property
1500containing a pair of the form `(LOCATION . VALUE)', where LOCATION is
1501one of `left-margin' or `right-margin' or nil. VALUE can be either a
1502string, an image specification or a stretch specification (see later
1503in this file).
1504
1505+++
1506** Help display
1507
1508Emacs displays short help messages in the echo area, when the mouse
1509moves over a tool-bar item or a piece of text that has a text property
1510`help-echo'. This feature also applies to strings in the mode line
1511that have a `help-echo' property.
1512
1513The value of the `help-echo' property must be a string. For tool-bar
1514items, their key definition is used to determine the help to display.
1515If their definition contains a property `:help FORM', FORM is
1516evaluated to determine the help string. Otherwise, the caption of the
1517tool-bar item is used.
1518
1519The hook `show-help-function' can be set to a function that displays
1520help differently. For example, enabling a tooltip window causes the
1521help display to appear there instead of in the echo area.
1522
1523+++
1524** Vertical fractional scrolling.
1525
1526The display of text in windows can be scrolled smoothly in pixels.
1527This is useful, for example, for making parts of large images visible.
1528
1529The function `window-vscroll' returns the current value of vertical
1530scrolling, a non-negative fraction of the canonical character height.
1531The function `set-window-vscroll' can be used to set the vertical
1532scrolling value. Here is an example of how these function might be
1533used.
1534
1535 (global-set-key [A-down]
1536 #'(lambda ()
1537 (interactive)
1538 (set-window-vscroll (selected-window)
1539 (+ 0.5 (window-vscroll)))))
1540 (global-set-key [A-up]
1541 #'(lambda ()
1542 (interactive)
1543 (set-window-vscroll (selected-window)
1544 (- (window-vscroll) 0.5)))))
1545
1546+++
1547** New hook `fontification-functions'.
1548
1549Functions from `fontification-functions' are called from redisplay
1550when it encounters a region of text that is not yet fontified. This
1551variable automatically becomes buffer-local when set. Each function
1552is called with one argument, POS.
1553
1554At least one of the hook functions should fontify one or more
1555characters starting at POS in the current buffer. It should mark them
1556as fontified by giving them a non-nil value of the `fontified' text
1557property. It may be reasonable for these functions to check for the
1558`fontified' property and not put it back on, but they do not have to.
1559
1560+++
1561** Tool bar support.
1562
1563Emacs supports a tool bar at the top of a frame under X. The frame
1564parameter `tool-bar-lines' (X resource "toolBar", class "ToolBar")
1565controls how may lines to reserve for the tool bar. A zero value
1566suppresses the tool bar. If the value is non-zero and
1567`auto-resize-tool-bars' is non-nil the tool bar's size will be changed
1568automatically so that all tool bar items are visible.
1569
1570*** Tool bar item definitions
1571
1572Tool bar items are defined using `define-key' with a prefix-key
1573`tool-bar'. For example `(define-key global-map [tool-bar item1] ITEM)'
1574where ITEM is a list `(menu-item CAPTION BINDING PROPS...)'.
1575
1576CAPTION is the caption of the item, If it's not a string, it is
1577evaluated to get a string. The caption is currently not displayed in
1578the tool bar, but it is displayed if the item doesn't have a `:help'
1579property (see below).
1580
1581BINDING is the tool bar item's binding. Tool bar items with keymaps as
1582binding are currently ignored.
1583
1584The following properties are recognized:
1585
1586`:enable FORM'.
1587
1588FORM is evaluated and specifies whether the tool bar item is enabled
1589or disabled.
1590
1591`:visible FORM'
1592
1593FORM is evaluated and specifies whether the tool bar item is displayed.
1594
1595`:filter FUNCTION'
1596
1597FUNCTION is called with one parameter, the same list BINDING in which
1598FUNCTION is specified as the filter. The value FUNCTION returns is
1599used instead of BINDING to display this item.
1600
1601`:button (TYPE SELECTED)'
1602
1603TYPE must be one of `:radio' or `:toggle'. SELECTED is evaluated
1604and specifies whether the button is selected (pressed) or not.
1605
1606`:image IMAGES'
1607
1608IMAGES is either a single image specification or a vector of four
1609image specifications. If it is a vector, this table lists the
1610meaning of each of the four elements:
1611
1612 Index Use when item is
1613 ----------------------------------------
1614 0 enabled and selected
1615 1 enabled and deselected
1616 2 disabled and selected
1617 3 disabled and deselected
1618
1619`:help HELP-STRING'.
1620
1621Gives a help string to display for the tool bar item. This help
1622is displayed when the mouse is moved over the item.
1623
1624*** Tool-bar-related variables.
1625
1626If `auto-resize-tool-bar' is non-nil, the tool bar will automatically
1627resize to show all defined tool bar items. It will never grow larger
1628than 1/4 of the frame's size.
1629
1630If `auto-raise-tool-bar-buttons' is non-nil, tool bar buttons will be
1631raised when the mouse moves over them.
1632
1633You can add extra space between tool bar items by setting
1634`tool-bar-button-margin' to a positive integer specifying a number of
1635pixels. Default is 1.
1636
1637You can change the shadow thickness of tool bar buttons by setting
1638`tool-bar-button-relief' to an integer. Default is 3.
1639
1640*** Tool-bar clicks with modifiers.
1641
1642You can bind commands to clicks with control, shift, meta etc. on
1643a tool bar item. If
1644
1645 (define-key global-map [tool-bar shell]
1646 '(menu-item "Shell" shell
1647 :image (image :type xpm :file "shell.xpm")))
1648
1649is the original tool bar item definition, then
1650
1651 (define-key global-map [tool-bar S-shell] 'some-command)
1652
1653makes a binding to run `some-command' for a shifted click on the same
1654item.
1655
1656** Mode line changes.
1657
1658+++
1659*** Mouse-sensitive mode line.
1660
1661The mode line can be made mouse-sensitive by displaying strings there
1662that have a `local-map' text property. There are three ways to display
1663a string with a `local-map' property in the mode line.
1664
16651. The mode line spec contains a variable whose string value has
1666a `local-map' text property.
1667
16682. The mode line spec contains a format specifier (e.g. `%12b'), and
1669that format specifier has a `local-map' property.
1670
16713. The mode line spec contains a list containing `:eval FORM'. FORM
1672is evaluated. If the result is a string, and that string has a
1673`local-map' property.
1674
1675The same mechanism is used to determine the `face' and `help-echo'
1676properties of strings in the mode line. See `bindings.el' for an
1677example.
1678
1679+++
1680*** You can suppress mode-line display by setting the buffer-local
1681variable mode-line-format to nil.
1682
1683+++
1684*** A headerline can now be displayed at the top of a window.
1685
1686This mode line's contents are controlled by the new variable
1687`header-line-format' and `default-header-line-format' which are
1688completely analogous to `mode-line-format' and
1689`default-mode-line-format'. A value of nil means don't display a top
1690line.
1691
1692The appearance of top mode lines is controlled by the face
1693`header-line'.
1694
1695The function `coordinates-in-window-p' returns `header-line' for a
1696position in the header-line.
1697
1698+++
1699** Text property `display'
1700
1701The `display' text property is used to insert images into text, and
1702also control other aspects of how text displays. The value of the
1703`display' property should be a display specification, as described
1704below, or a list or vector containing display specifications.
1705
1706*** Variable width and height spaces
1707
1708To display a space of fractional width or height, use a display
1709specification of the form `(LOCATION STRECH)'. If LOCATION is
1710`(margin left-margin)', the space is displayed in the left marginal
1711area, if it is `(margin right-margin)', it is displayed in the right
1712marginal area, and if LOCATION is `(margin nil)' the space is
1713displayed in the text. In the latter case you can also use the
1714simpler form STRETCH as property value.
1715
1716The stretch specification STRETCH itself is a list of the form `(space
1717PROPS)', where PROPS is a property list which can contain the
1718properties described below.
1719
1720The display of the fractional space replaces the display of the
1721characters having the `display' property.
1722
1723- :width WIDTH
1724
1725Specifies that the space width should be WIDTH times the normal
1726character width. WIDTH can be an integer or floating point number.
1727
1728- :relative-width FACTOR
1729
1730Specifies that the width of the stretch should be computed from the
1731first character in a group of consecutive characters that have the
1732same `display' property. The computation is done by multiplying the
1733width of that character by FACTOR.
1734
1735- :align-to HPOS
1736
1737Specifies that the space should be wide enough to reach HPOS. The
1738value HPOS is measured in units of the normal character width.
1739
1740Exactly one of the above properties should be used.
1741
1742- :height HEIGHT
1743
1744Specifies the height of the space, as HEIGHT, measured in terms of the
1745normal line height.
1746
1747- :relative-height FACTOR
1748
1749The height of the space is computed as the product of the height
1750of the text having the `display' property and FACTOR.
1751
1752- :ascent ASCENT
1753
1754Specifies that ASCENT percent of the height of the stretch should be
1755used for the ascent of the stretch, i.e. for the part above the
1756baseline. The value of ASCENT must be a non-negative number less or
1757equal to 100.
1758
1759You should not use both `:height' and `:relative-height' together.
1760
1761*** Images
1762
1763A display specification for an image has the form `(LOCATION
1764. IMAGE)', where IMAGE is an image specification. The image replaces,
1765in the display, the characters having this display specification in
1766their `display' text property. If LOCATION is `(margin left-margin)',
1767the image will be displayed in the left marginal area, if it is
1768`(margin right-margin)' it will be displayed in the right marginal
1769area, and if LOCATION is `(margin nil)' the image will be displayed in
1770the text. In the latter case you can also use the simpler form IMAGE
1771as display specification.
1772
1773*** Other display properties
1774
1775- :space-width FACTOR
1776
1777Specifies that space characters in the text having that property
1778should be displayed FACTOR times as wide as normal; FACTOR must be an
1779integer or float.
1780
1781- :height HEIGHT
1782
1783Display text having this property in a font that is smaller or larger.
1784
1785If HEIGHT is a list of the form `(+ N)', where N is an integer, that
1786means to use a font that is N steps larger. If HEIGHT is a list of
1787the form `(- N)', that means to use a font that is N steps smaller. A
1788``step'' is defined by the set of available fonts; each size for which
1789a font is available counts as a step.
1790
1791If HEIGHT is a number, that means to use a font that is HEIGHT times
1792as tall as the frame's default font.
1793
1794If HEIGHT is a symbol, it is called as a function with the current
1795height as argument. The function should return the new height to use.
1796
1797Otherwise, HEIGHT is evaluated to get the new height, with the symbol
1798`height' bound to the current specified font height.
1799
1800- :raise FACTOR
1801
1802FACTOR must be a number, specifying a multiple of the current
1803font's height. If it is positive, that means to display the characters
1804raised. If it is negative, that means to display them lower down. The
1805amount of raising or lowering is computed without taking account of the
1806`:height' subproperty.
1807
1808*** Conditional display properties
1809
1810All display specifications can be conditionalized. If a specification
1811has the form `(:when CONDITION . SPEC)', the specification SPEC
1812applies only when CONDITION yields a non-nil value when evaluated.
1813During evaluattion, point is temporarily set to the end position of
1814the text having the `display' property.
1815
1816The normal specification consisting of SPEC only is equivalent to
1817`(:when t SPEC)'.
1818
1819+++
1820** New menu separator types.
1821
1822Emacs now supports more than one menu separator type. Menu items with
1823item names consisting of dashes only (including zero dashes) are
1824treated like before. In addition, the following item names are used
1825to specify other menu separator types.
1826
1827- `--no-line' or `--space', or `--:space', or `--:noLine'
1828
1829No separator lines are drawn, but a small space is inserted where the
1830separator occurs.
1831
1832- `--single-line' or `--:singleLine'
1833
1834A single line in the menu's foreground color.
1835
1836- `--double-line' or `--:doubleLine'
1837
1838A double line in the menu's foreground color.
1839
1840- `--single-dashed-line' or `--:singleDashedLine'
1841
1842A single dashed line in the menu's foreground color.
1843
1844- `--double-dashed-line' or `--:doubleDashedLine'
1845
1846A double dashed line in the menu's foreground color.
1847
1848- `--shadow-etched-in' or `--:shadowEtchedIn'
1849
1850A single line with 3D sunken appearance. This is the the form
1851displayed for item names consisting of dashes only.
1852
1853- `--shadow-etched-out' or `--:shadowEtchedOut'
1854
1855A single line with 3D raised appearance.
1856
1857- `--shadow-etched-in-dash' or `--:shadowEtchedInDash'
1858
1859A single dashed line with 3D sunken appearance.
1860
1861- `--shadow-etched-out-dash' or `--:shadowEtchedOutDash'
1862
1863A single dashed line with 3D raise appearance.
1864
1865- `--shadow-double-etched-in' or `--:shadowDoubleEtchedIn'
1866
1867Two lines with 3D sunken appearance.
1868
1869- `--shadow-double-etched-out' or `--:shadowDoubleEtchedOut'
1870
1871Two lines with 3D raised appearance.
1872
1873- `--shadow-double-etched-in-dash' or `--:shadowDoubleEtchedInDash'
1874
1875Two dashed lines with 3D sunken appearance.
1876
1877- `--shadow-double-etched-out-dash' or `--:shadowDoubleEtchedOutDash'
1878
1879Two dashed lines with 3D raised appearance.
1880
1881Under LessTif/Motif, the last four separator types are displayed like
1882the corresponding single-line separators.
1883
1884+++
1885** New frame parameters for scroll bar colors.
1886
1887The new frame parameters `scroll-bar-foreground' and
1888`scroll-bar-background' can be used to change scroll bar colors.
1889Their value must be either a color name, a string, or nil to specify
1890that scroll bars should use a default color. For toolkit scroll bars,
1891default colors are toolkit specific. For non-toolkit scroll bars, the
1892default background is the background color of the frame, and the
1893default foreground is black.
1894
1895The X resource name of these parameters are `scrollBarForeground'
1896(class ScrollBarForeground) and `scrollBarBackground' (class
1897`ScrollBarBackground').
1898
1899Setting these parameters overrides toolkit specific X resource
1900settings for scroll bar colors.
1901
1902+++
1903** You can set `redisplay-dont-pause' to a non-nil value to prevent
1904display updates from being interrupted when input is pending.
1905
1906---
1907** Changing a window's width may now change its window start if it
1908starts on a continuation line. The new window start is computed based
1909on the window's new width, starting from the start of the continued
1910line as the start of the screen line with the minimum distance from
1911the original window start.
1912
1913---
1914** The variable `hscroll-step' and the functions
1915`hscroll-point-visible' and `hscroll-window-column' have been removed
1916now that proper horizontal scrolling is implemented.
1917
1918+++
1919** Windows can now be made fixed-width and/or fixed-height.
1920
1921A window is fixed-size if its buffer has a buffer-local variable
1922`window-size-fixed' whose value is not nil. A value of `height' makes
1923windows fixed-height, a value of `width' makes them fixed-width, any
1924other non-nil value makes them both fixed-width and fixed-height.
1925
1926The following code makes all windows displaying the current buffer
1927fixed-width and fixed-height.
1928
1929 (set (make-local-variable 'window-size-fixed) t)
1930
1931A call to enlarge-window on a window gives an error if that window is
1932fixed-width and it is tried to change the window's width, or if the
1933window is fixed-height, and it is tried to change its height. To
1934change the size of a fixed-size window, bind `window-size-fixed'
1935temporarily to nil, for example
1936
1937 (let ((window-size-fixed nil))
1938 (enlarge-window 10))
1939
1940Likewise, an attempt to split a fixed-height window vertically,
1941or a fixed-width window horizontally results in a error.
1942\f
1943* Changes in Emacs 20.4
1944
1945** Init file may be called .emacs.el.
1946
1947You can now call the Emacs init file `.emacs.el'.
1948Formerly the name had to be `.emacs'. If you use the name
1949`.emacs.el', you can byte-compile the file in the usual way.
1950
1951If both `.emacs' and `.emacs.el' exist, the latter file
1952is the one that is used.
1953
1954** shell-command, and shell-command-on-region, now return
1955the exit code of the command (unless it is asynchronous).
1956Also, you can specify a place to put the error output,
1957separate from the command's regular output.
1958Interactively, the variable shell-command-default-error-buffer
1959says where to put error output; set it to a buffer name.
1960In calls from Lisp, an optional argument ERROR-BUFFER specifies
1961the buffer name.
1962
1963When you specify a non-nil error buffer (or buffer name), any error
1964output is inserted before point in that buffer, with \f\n to separate
1965it from the previous batch of error output. The error buffer is not
1966cleared, so error output from successive commands accumulates there.
1967
1968** Setting the default value of enable-multibyte-characters to nil in
1969the .emacs file, either explicitly using setq-default, or via Custom,
1970is now essentially equivalent to using --unibyte: all buffers
1971created during startup will be made unibyte after loading .emacs.
1972
1973** C-x C-f now handles the wildcards * and ? in file names. For
1974example, typing C-x C-f c*.c RET visits all the files whose names
1975match c*.c. To visit a file whose name contains * or ?, add the
1976quoting sequence /: to the beginning of the file name.
1977
1978** The M-x commands keep-lines, flush-lines and count-matches
1979now have the same feature as occur and query-replace:
1980if the pattern contains any upper case letters, then
1981they never ignore case.
1982
1983** The end-of-line format conversion feature previously mentioned
1984under `* Emacs 20.1 changes for MS-DOS and MS-Windows' actually
1985applies to all operating systems. Emacs recognizes from the contents
1986of a file what convention it uses to separate lines--newline, CRLF, or
1987just CR--and automatically converts the contents to the normal Emacs
1988convention (using newline to separate lines) for editing. This is a
1989part of the general feature of coding system conversion.
1990
1991If you subsequently save the buffer, Emacs converts the text back to
1992the same format that was used in the file before.
1993
1994You can turn off end-of-line conversion by setting the variable
1995`inhibit-eol-conversion' to non-nil, e.g. with Custom in the MULE group.
1996
1997** The character set property `prefered-coding-system' has been
1998renamed to `preferred-coding-system', for the sake of correct spelling.
1999This is a fairly internal feature, so few programs should be affected.
2000
2001** Mode-line display of end-of-line format is changed.
2002The indication of the end-of-line format of the file visited by a
2003buffer is now more explicit when that format is not the usual one for
2004your operating system. For example, the DOS-style end-of-line format
2005is displayed as "(DOS)" on Unix and GNU/Linux systems. The usual
2006end-of-line format is still displayed as a single character (colon for
2007Unix, backslash for DOS and Windows, and forward slash for the Mac).
2008
2009The values of the variables eol-mnemonic-unix, eol-mnemonic-dos,
2010eol-mnemonic-mac, and eol-mnemonic-undecided, which are strings,
2011control what is displayed in the mode line for each end-of-line
2012format. You can now customize these variables.
2013
2014** In the previous version of Emacs, tar-mode didn't work well if a
2015filename contained non-ASCII characters. Now this is fixed. Such a
2016filename is decoded by file-name-coding-system if the default value of
2017enable-multibyte-characters is non-nil.
2018
2019** The command temp-buffer-resize-mode toggles a minor mode
2020in which temporary buffers (such as help buffers) are given
2021windows just big enough to hold the whole contents.
2022
2023** If you use completion.el, you must now run the function
2024dynamic-completion-mode to enable it. Just loading the file
2025doesn't have any effect.
2026
2027** In Flyspell mode, the default is now to make just one Ispell process,
2028not one per buffer.
2029
2030** If you use iswitchb but do not call (iswitchb-default-keybindings) to
2031use the default keybindings, you will need to add the following line:
2032 (add-hook 'minibuffer-setup-hook 'iswitchb-minibuffer-setup)
2033
2034** Auto-show mode is no longer enabled just by loading auto-show.el.
2035To control it, set `auto-show-mode' via Custom or use the
2036`auto-show-mode' command.
2037
2038** Handling of X fonts' ascent/descent parameters has been changed to
2039avoid redisplay problems. As a consequence, compared with previous
2040versions the line spacing and frame size now differ with some font
2041choices, typically increasing by a pixel per line. This change
2042occurred in version 20.3 but was not documented then.
2043
2044** If you select the bar cursor style, it uses the frame's
2045cursor-color, rather than the cursor foreground pixel.
2046
2047** In multibyte mode, Rmail decodes incoming MIME messages using the
2048character set specified in the message. If you want to disable this
2049feature, set the variable rmail-decode-mime-charset to nil.
2050
2051** Not new, but not mentioned previously in NEWS: when you use #! at
2052the beginning of a file to make it executable and specify an
2053interpreter program, Emacs looks on the second line for the -*- mode
2054and variable specification, as well as on the first line.
2055
2056** Support for IBM codepage encoding of non-ASCII characters.
2057
2058The new command M-x codepage-setup creates a special coding system
2059that can be used to convert text between a specific IBM codepage and
2060one of the character sets built into Emacs which matches that
2061codepage. For example, codepage 850 corresponds to Latin-1 character
2062set, codepage 855 corresponds to Cyrillic-ISO character set, etc.
2063
2064Windows codepages 1250, 1251 and some others, where Windows deviates
2065from the corresponding ISO character set, are also supported.
2066
2067IBM box-drawing characters and other glyphs which don't have
2068equivalents in the corresponding ISO character set, are converted to
2069a character defined by dos-unsupported-char-glyph on MS-DOS, and to
2070`?' on other systems.
2071
2072IBM codepages are widely used on MS-DOS and MS-Windows, so this
2073feature is most useful on those platforms, but it can also be used on
2074Unix.
2075
2076Emacs compiled for MS-DOS automatically loads the support for the
2077current codepage when it starts.
2078
2079** Mail changes
2080
2081*** The new variable default-sendmail-coding-system specifies the
2082default way to encode outgoing mail. This has higher priority than
2083default-buffer-file-coding-system but has lower priority than
2084sendmail-coding-system and the local value of
2085buffer-file-coding-system.
2086
2087You should not set this variable manually. Instead, set
2088sendmail-coding-system to specify a fixed encoding for all outgoing
2089mail.
2090
2091*** When you try to send a message that contains non-ASCII characters,
2092if the coding system specified by those variables doesn't handle them,
2093Emacs will ask you to select a suitable coding system while showing a
2094list of possible coding systems.
2095
2096** CC Mode changes
2097
2098*** c-default-style can now take an association list that maps major
2099modes to style names. When this variable is an alist, Java mode no
2100longer hardcodes a setting to "java" style. See the variable's
2101docstring for details.
2102
2103*** It's now possible to put a list as the offset on a syntactic
2104symbol. The list is evaluated recursively until a non-nil offset is
2105found. This is useful to combine several lineup functions to act in a
2106prioritized order on a single line. However, none of the supplied
2107lineup functions use this feature currently.
2108
2109*** New syntactic symbol catch-clause, which is used on the "catch" and
2110"finally" lines in try-catch constructs in C++ and Java.
2111
2112*** New cleanup brace-catch-brace on c-cleanup-list, which does for
2113"catch" lines what brace-elseif-brace does for "else if" lines.
2114
2115*** The braces of Java anonymous inner classes are treated separately
2116from the braces of other classes in auto-newline mode. Two new
2117symbols inexpr-class-open and inexpr-class-close may be used on
2118c-hanging-braces-alist to control the automatic newlines used for
2119anonymous classes.
2120
2121*** Support for the Pike language added, along with new Pike specific
2122syntactic symbols: inlambda, lambda-intro-cont
2123
2124*** Support for Java anonymous classes via new syntactic symbol
2125inexpr-class. New syntactic symbol inexpr-statement for Pike
2126support and gcc-style statements inside expressions. New lineup
2127function c-lineup-inexpr-block.
2128
2129*** New syntactic symbol brace-entry-open which is used in brace lists
2130(i.e. static initializers) when a list entry starts with an open
2131brace. These used to be recognized as brace-list-entry's.
2132c-electric-brace also recognizes brace-entry-open braces
2133(brace-list-entry's can no longer be electrified).
2134
2135*** New command c-indent-line-or-region, not bound by default.
2136
2137*** `#' is only electric when typed in the indentation of a line.
2138
2139*** Parentheses are now electric (via the new command c-electric-paren)
2140for auto-reindenting lines when parens are typed.
2141
2142*** In "gnu" style, inline-open offset is now set to zero.
2143
2144*** Uniform handling of the inclass syntactic symbol. The indentation
2145associated with it is now always relative to the class opening brace.
2146This means that the indentation behavior has changed in some
2147circumstances, but only if you've put anything besides 0 on the
2148class-open syntactic symbol (none of the default styles do that).
2149
2150** Gnus changes.
2151
2152*** New functionality for using Gnus as an offline newsreader has been
2153added. A plethora of new commands and modes have been added. See the
2154Gnus manual for the full story.
2155
2156*** The nndraft backend has returned, but works differently than
2157before. All Message buffers are now also articles in the nndraft
2158group, which is created automatically.
2159
2160*** `gnus-alter-header-function' can now be used to alter header
2161values.
2162
2163*** `gnus-summary-goto-article' now accept Message-ID's.
2164
2165*** A new Message command for deleting text in the body of a message
2166outside the region: `C-c C-v'.
2167
2168*** You can now post to component group in nnvirtual groups with
2169`C-u C-c C-c'.
2170
2171*** `nntp-rlogin-program' -- new variable to ease customization.
2172
2173*** `C-u C-c C-c' in `gnus-article-edit-mode' will now inhibit
2174re-highlighting of the article buffer.
2175
2176*** New element in `gnus-boring-article-headers' -- `long-to'.
2177
2178*** `M-i' symbolic prefix command. See the section "Symbolic
2179Prefixes" in the Gnus manual for details.
2180
2181*** `L' and `I' in the summary buffer now take the symbolic prefix
2182`a' to add the score rule to the "all.SCORE" file.
2183
2184*** `gnus-simplify-subject-functions' variable to allow greater
2185control over simplification.
2186
2187*** `A T' -- new command for fetching the current thread.
2188
2189*** `/ T' -- new command for including the current thread in the
2190limit.
2191
2192*** `M-RET' is a new Message command for breaking cited text.
2193
2194*** \\1-expressions are now valid in `nnmail-split-methods'.
2195
2196*** The `custom-face-lookup' function has been removed.
2197If you used this function in your initialization files, you must
2198rewrite them to use `face-spec-set' instead.
2199
2200*** Cancelling now uses the current select method. Symbolic prefix
2201`a' forces normal posting method.
2202
2203*** New command to translate M******** sm*rtq**t*s into proper text
2204-- `W d'.
2205
2206*** For easier debugging of nntp, you can set `nntp-record-commands'
2207to a non-nil value.
2208
2209*** nntp now uses ~/.authinfo, a .netrc-like file, for controlling
2210where and how to send AUTHINFO to NNTP servers.
2211
2212*** A command for editing group parameters from the summary buffer
2213has been added.
2214
2215*** A history of where mails have been split is available.
2216
2217*** A new article date command has been added -- `article-date-iso8601'.
2218
2219*** Subjects can be simplified when threading by setting
2220`gnus-score-thread-simplify'.
2221
2222*** A new function for citing in Message has been added --
2223`message-cite-original-without-signature'.
2224
2225*** `article-strip-all-blank-lines' -- new article command.
2226
2227*** A new Message command to kill to the end of the article has
2228been added.
2229
2230*** A minimum adaptive score can be specified by using the
2231`gnus-adaptive-word-minimum' variable.
2232
2233*** The "lapsed date" article header can be kept continually
2234updated by the `gnus-start-date-timer' command.
2235
2236*** Web listserv archives can be read with the nnlistserv backend.
2237
2238*** Old dejanews archives can now be read by nnweb.
2239
2240*** `gnus-posting-styles' has been re-activated.
2241
2242** Changes to TeX and LaTeX mode
2243
2244*** The new variable `tex-start-options-string' can be used to give
2245options for the TeX run. The default value causes TeX to run in
2246nonstopmode. For an interactive TeX run set it to nil or "".
2247
2248*** The command `tex-feed-input' sends input to the Tex Shell. In a
2249TeX buffer it is bound to the keys C-RET, C-c RET, and C-c C-m (some
2250of these keys may not work on all systems). For instance, if you run
2251TeX interactively and if the TeX run stops because of an error, you
2252can continue it without leaving the TeX buffer by typing C-RET.
2253
2254*** The Tex Shell Buffer is now in `compilation-shell-minor-mode'.
2255All error-parsing commands of the Compilation major mode are available
2256but bound to keys that don't collide with the shell. Thus you can use
2257the Tex Shell for command line executions like a usual shell.
2258
2259*** The commands `tex-validate-region' and `tex-validate-buffer' check
2260the matching of braces and $'s. The errors are listed in a *Occur*
2261buffer and you can use C-c C-c or mouse-2 to go to a particular
2262mismatch.
2263
2264** Changes to RefTeX mode
2265
2266*** The table of contents buffer can now also display labels and
2267file boundaries in addition to sections. Use `l', `i', and `c' keys.
2268
2269*** Labels derived from context (the section heading) are now
2270lowercase by default. To make the label legal in LaTeX, latin-1
2271characters will lose their accent. All Mule characters will be
2272removed from the label.
2273
2274*** The automatic display of cross reference information can also use
2275a window instead of the echo area. See variable `reftex-auto-view-crossref'.
2276
2277*** kpsewhich can be used by RefTeX to find TeX and BibTeX files. See the
2278customization group `reftex-finding-files'.
2279
2280*** The option `reftex-bibfile-ignore-list' has been renamed to
2281`reftex-bibfile-ignore-regexps' and indeed can be fed with regular
2282expressions.
2283
2284*** Multiple Selection buffers are now hidden buffers.
2285
2286** New/deleted modes and packages
2287
2288*** The package snmp-mode.el provides major modes for editing SNMP and
2289SNMPv2 MIBs. It has entries on `auto-mode-alist'.
2290
2291*** The package sql.el provides a major mode, M-x sql-mode, for
2292editing SQL files, and M-x sql-interactive-mode for interacting with
2293SQL interpreters. It has an entry on `auto-mode-alist'.
2294
2295*** M-x highlight-changes-mode provides a minor mode displaying buffer
2296changes with a special face.
2297
2298*** ispell4.el has been deleted. It got in the way of ispell.el and
2299this was hard to fix reliably. It has long been obsolete -- use
2300Ispell 3.1 and ispell.el.
2301\f
2302* MS-DOS changes in Emacs 20.4
2303
2304** Emacs compiled for MS-DOS now supports MULE features better.
2305This includes support for display of all ISO 8859-N character sets,
2306conversion to and from IBM codepage encoding of non-ASCII characters,
2307and automatic setup of the MULE environment at startup. For details,
2308check out the section `MS-DOS and MULE' in the manual.
2309
2310The MS-DOS installation procedure automatically configures and builds
2311Emacs with input method support if it finds an unpacked Leim
2312distribution when the config.bat script is run.
2313
2314** Formerly, the value of lpr-command did not affect printing on
2315MS-DOS unless print-region-function was set to nil, but now it
2316controls whether an external program is invoked or output is written
2317directly to a printer port. Similarly, in the previous version of
2318Emacs, the value of ps-lpr-command did not affect PostScript printing
2319on MS-DOS unless ps-printer-name was set to something other than a
2320string (eg. t or `pipe'), but now it controls whether an external
2321program is used. (These changes were made so that configuration of
2322printing variables would be almost identical across all platforms.)
2323
2324** In the previous version of Emacs, PostScript and non-PostScript
2325output was piped to external programs, but because most print programs
2326available for MS-DOS and MS-Windows cannot read data from their standard
2327input, on those systems the data to be output is now written to a
2328temporary file whose name is passed as the last argument to the external
2329program.
2330
2331An exception is made for `print', a standard program on Windows NT,
2332and `nprint', a standard program on Novell Netware. For both of these
2333programs, the command line is constructed in the appropriate syntax
2334automatically, using only the value of printer-name or ps-printer-name
2335as appropriate--the value of the relevant `-switches' variable is
2336ignored, as both programs have no useful switches.
2337
2338** The value of the variable dos-printer (cf. dos-ps-printer), if it has
2339a value, overrides the value of printer-name (cf. ps-printer-name), on
2340MS-DOS and MS-Windows only. This has been true since version 20.3, but
2341was not documented clearly before.
2342
2343** All the Emacs games now work on MS-DOS terminals.
2344This includes Tetris and Snake.
2345\f
2346* Lisp changes in Emacs 20.4
2347
2348** New functions line-beginning-position and line-end-position
2349return the position of the beginning or end of the current line.
2350They both accept an optional argument, which has the same
2351meaning as the argument to beginning-of-line or end-of-line.
2352
2353** find-file and allied functions now have an optional argument
2354WILDCARD. If this is non-nil, they do wildcard processing,
2355and visit all files that match the wildcard pattern.
2356
2357** Changes in the file-attributes function.
2358
2359*** The file size returned by file-attributes may be an integer or a float.
2360It is an integer if the size fits in a Lisp integer, float otherwise.
2361
2362*** The inode number returned by file-attributes may be an integer (if
2363the number fits in a Lisp integer) or a cons cell containing two
2364integers.
2365
2366** The new function directory-files-and-attributes returns a list of
2367files in a directory and their attributes. It accepts the same
2368arguments as directory-files and has similar semantics, except that
2369file names and attributes are returned.
2370
2371** The new function file-attributes-lessp is a helper function for
2372sorting the list generated by directory-files-and-attributes. It
2373accepts two arguments, each a list of a file name and its atttributes.
2374It compares the file names of each according to string-lessp and
2375returns the result.
2376
2377** The new function file-expand-wildcards expands a wildcard-pattern
2378to produce a list of existing files that match the pattern.
2379
2380** New functions for base64 conversion:
2381
2382The function base64-encode-region converts a part of the buffer
2383into the base64 code used in MIME. base64-decode-region
2384performs the opposite conversion. Line-breaking is supported
2385optionally.
2386
2387Functions base64-encode-string and base64-decode-string do a similar
2388job on the text in a string. They return the value as a new string.
2389
2390**
2391The new function process-running-child-p
2392will tell you if a subprocess has given control of its
2393terminal to its own child process.
2394
2395** interrupt-process and such functions have a new feature:
2396when the second argument is `lambda', they send a signal
2397to the running child of the subshell, if any, but if the shell
2398itself owns its terminal, no signal is sent.
2399
2400** There are new widget types `plist' and `alist' which can
2401be used for customizing variables whose values are plists or alists.
2402
2403** easymenu.el Now understands `:key-sequence' and `:style button'.
2404:included is an alias for :visible.
2405
2406easy-menu-add-item now understands the values returned by
2407easy-menu-remove-item and easy-menu-item-present-p. This can be used
2408to move or copy menu entries.
2409
2410** Multibyte editing changes
2411
2412*** The definitions of sref and char-bytes are changed. Now, sref is
2413an alias of aref and char-bytes always returns 1. This change is to
2414make some Emacs Lisp code which works on 20.2 and earlier also
2415work on the latest Emacs. Such code uses a combination of sref and
2416char-bytes in a loop typically as below:
2417 (setq char (sref str idx)
2418 idx (+ idx (char-bytes idx)))
2419The byte-compiler now warns that this is obsolete.
2420
2421If you want to know how many bytes a specific multibyte character
2422(say, CH) occupies in a multibyte buffer, use this code:
2423 (charset-bytes (char-charset ch))
2424
2425*** In multibyte mode, when you narrow a buffer to some region, and the
2426region is preceded or followed by non-ASCII codes, inserting or
2427deleting at the head or the end of the region may signal this error:
2428
2429 Byte combining across boundary of accessible buffer text inhibitted
2430
2431This is to avoid some bytes being combined together into a character
2432across the boundary.
2433
2434*** The functions find-charset-region and find-charset-string include
2435`unknown' in the returned list in the following cases:
2436 o The current buffer or the target string is unibyte and
2437 contains 8-bit characters.
2438 o The current buffer or the target string is multibyte and
2439 contains invalid characters.
2440
2441*** The functions decode-coding-region and encode-coding-region remove
2442text properties of the target region. Ideally, they should correctly
2443preserve text properties, but for the moment, it's hard. Removing
2444text properties is better than preserving them in a less-than-correct
2445way.
2446
2447*** prefer-coding-system sets EOL conversion of default coding systems.
2448If the argument to prefer-coding-system specifies a certain type of
2449end of line conversion, the default coding systems set by
2450prefer-coding-system will specify that conversion type for end of line.
2451
2452*** The new function thai-compose-string can be used to properly
2453compose Thai characters in a string.
2454
2455** The primitive `define-prefix-command' now takes an optional third
2456argument NAME, which should be a string. It supplies the menu name
2457for the created keymap. Keymaps created in order to be displayed as
2458menus should always use the third argument.
2459
2460** The meanings of optional second arguments for read-char,
2461read-event, and read-char-exclusive are flipped. Now the second
2462arguments are INHERIT-INPUT-METHOD. These functions use the current
2463input method (if any) if and only if INHERIT-INPUT-METHOD is non-nil.
2464
2465** The new function clear-this-command-keys empties out the contents
2466of the vector that (this-command-keys) returns. This is useful in
2467programs that read passwords, to prevent the passwords from echoing
2468inadvertently as part of the next command in certain cases.
2469
2470** The new macro `with-temp-message' displays a temporary message in
2471the echo area, while executing some Lisp code. Like `progn', it
2472returns the value of the last form, but it also restores the previous
2473echo area contents.
2474
2475 (with-temp-message MESSAGE &rest BODY)
2476
2477** The function `require' now takes an optional third argument
2478NOERROR. If it is non-nil, then there is no error if the
2479requested feature cannot be loaded.
2480
2481** In the function modify-face, an argument of (nil) for the
2482foreground color, background color or stipple pattern
2483means to clear out that attribute.
2484
2485** The `outer-window-id' frame property of an X frame
2486gives the window number of the outermost X window for the frame.
2487
2488** Temporary buffers made with with-output-to-temp-buffer are now
2489read-only by default, and normally use the major mode Help mode
2490unless you put them in some other non-Fundamental mode before the
2491end of with-output-to-temp-buffer.
2492
2493** The new functions gap-position and gap-size return information on
2494the gap of the current buffer.
2495
2496** The new functions position-bytes and byte-to-position provide a way
2497to convert between character positions and byte positions in the
2498current buffer.
2499
2500** vc.el defines two new macros, `edit-vc-file' and `with-vc-file', to
2501facilitate working with version-controlled files from Lisp programs.
2502These macros check out a given file automatically if needed, and check
2503it back in after any modifications have been made.
2504\f
2505* Installation Changes in Emacs 20.3
2506
2507** The default value of load-path now includes most subdirectories of
2508the site-specific directories /usr/local/share/emacs/site-lisp and
2509/usr/local/share/emacs/VERSION/site-lisp, in addition to those
2510directories themselves. Both immediate subdirectories and
2511subdirectories multiple levels down are added to load-path.
2512
2513Not all subdirectories are included, though. Subdirectories whose
2514names do not start with a letter or digit are excluded.
2515Subdirectories named RCS or CVS are excluded. Also, a subdirectory
2516which contains a file named `.nosearch' is excluded. You can use
2517these methods to prevent certain subdirectories from being searched.
2518
2519Emacs finds these subdirectories and adds them to load-path when it
2520starts up. While it would be cleaner to find the subdirectories each
2521time Emacs loads a file, that would be much slower.
2522
2523This feature is an incompatible change. If you have stored some Emacs
2524Lisp files in a subdirectory of the site-lisp directory specifically
2525to prevent them from being used, you will need to rename the
2526subdirectory to start with a non-alphanumeric character, or create a
2527`.nosearch' file in it, in order to continue to achieve the desired
2528results.
2529
2530** Emacs no longer includes an old version of the C preprocessor from
2531GCC. This was formerly used to help compile Emacs with C compilers
2532that had limits on the significant length of an identifier, but in
2533fact we stopped supporting such compilers some time ago.
2534\f
2535* Changes in Emacs 20.3
2536
2537** The new command C-x z (repeat) repeats the previous command
2538including its argument. If you repeat the z afterward,
2539it repeats the command additional times; thus, you can
2540perform many repetitions with one keystroke per repetition.
2541
2542** Emacs now supports "selective undo" which undoes only within a
2543specified region. To do this, set point and mark around the desired
2544region and type C-u C-x u (or C-u C-_). You can then continue undoing
2545further, within the same region, by repeating the ordinary undo
2546command C-x u or C-_. This will keep undoing changes that were made
2547within the region you originally specified, until either all of them
2548are undone, or it encounters a change which crosses the edge of that
2549region.
2550
2551In Transient Mark mode, undoing when a region is active requests
2552selective undo.
2553
2554** If you specify --unibyte when starting Emacs, then all buffers are
2555unibyte, except when a Lisp program specifically creates a multibyte
2556buffer. Setting the environment variable EMACS_UNIBYTE has the same
2557effect. The --no-unibyte option overrides EMACS_UNIBYTE and directs
2558Emacs to run normally in multibyte mode.
2559
2560The option --unibyte does not affect the reading of Emacs Lisp files,
2561though. If you want a Lisp file to be read in unibyte mode, use
2562-*-unibyte: t;-*- on its first line. That will force Emacs to
2563load that file in unibyte mode, regardless of how Emacs was started.
2564
2565** toggle-enable-multibyte-characters no longer has a key binding and
2566no longer appears in the menu bar. We've realized that changing the
2567enable-multibyte-characters variable in an existing buffer is
2568something that most users not do.
2569
2570** You can specify a coding system to use for the next cut or paste
2571operations through the window system with the command C-x RET X.
2572The coding system can make a difference for communication with other
2573applications.
2574
2575C-x RET x specifies a coding system for all subsequent cutting and
2576pasting operations.
2577
2578** You can specify the printer to use for commands that do printing by
2579setting the variable `printer-name'. Just what a printer name looks
2580like depends on your operating system. You can specify a different
2581printer for the Postscript printing commands by setting
2582`ps-printer-name'.
2583
2584** Emacs now supports on-the-fly spell checking by the means of a
2585minor mode. It is called M-x flyspell-mode. You don't have to remember
2586any other special commands to use it, and you will hardly notice it
2587except when you make a spelling error. Flyspell works by highlighting
2588incorrect words as soon as they are completed or as soon as the cursor
2589hits a new word.
2590
2591Flyspell mode works with whichever dictionary you have selected for
2592Ispell in Emacs. In TeX mode, it understands TeX syntax so as not
2593to be confused by TeX commands.
2594
2595You can correct a misspelled word by editing it into something
2596correct. You can also correct it, or accept it as correct, by
2597clicking on the word with Mouse-2; that gives you a pop-up menu
2598of various alternative replacements and actions.
2599
2600Flyspell mode also proposes "automatic" corrections. M-TAB replaces
2601the current misspelled word with a possible correction. If several
2602corrections are made possible, M-TAB cycles through them in
2603alphabetical order, or in order of decreasing likelihood if
2604flyspell-sort-corrections is nil.
2605
2606Flyspell mode also flags an error when a word is repeated, if
2607flyspell-mark-duplications-flag is non-nil.
2608
2609** Changes in input method usage.
2610
2611Now you can use arrow keys (right, left, down, up) for selecting among
2612the alternatives just the same way as you do by C-f, C-b, C-n, and C-p
2613respectively.
2614
2615You can use the ENTER key to accept the current conversion.
2616
2617If you type TAB to display a list of alternatives, you can select one
2618of the alternatives with Mouse-2.
2619
2620The meaning of the variable `input-method-verbose-flag' is changed so
2621that you can set it to t, nil, `default', or `complex-only'.
2622
2623 If the value is nil, extra guidance is never given.
2624
2625 If the value is t, extra guidance is always given.
2626
2627 If the value is `complex-only', extra guidance is always given only
2628 when you are using complex input methods such as chinese-py.
2629
2630 If the value is `default' (this is the default), extra guidance is
2631 given in the following case:
2632 o When you are using a complex input method.
2633 o When you are using a simple input method but not in the minibuffer.
2634
2635If you are using Emacs through a very slow line, setting
2636input-method-verbose-flag to nil or to complex-only is a good choice,
2637and if you are using an input method you are not familiar with,
2638setting it to t is helpful.
2639
2640The old command select-input-method is now called set-input-method.
2641
2642In the language environment "Korean", you can use the following
2643keys:
2644 Shift-SPC toggle-korean-input-method
2645 C-F9 quail-hangul-switch-symbol-ksc
2646 F9 quail-hangul-switch-hanja
2647These key bindings are canceled when you switch to another language
2648environment.
2649
2650** The minibuffer history of file names now records the specified file
2651names, not the entire minibuffer input. For example, if the
2652minibuffer starts out with /usr/foo/, you might type in /etc/passwd to
2653get
2654
2655 /usr/foo//etc/passwd
2656
2657which stands for the file /etc/passwd.
2658
2659Formerly, this used to put /usr/foo//etc/passwd in the history list.
2660Now this puts just /etc/passwd in the history list.
2661
2662** If you are root, Emacs sets backup-by-copying-when-mismatch to t
2663at startup, so that saving a file will be sure to preserve
2664its owner and group.
2665
2666** find-func.el can now also find the place of definition of Emacs
2667Lisp variables in user-loaded libraries.
2668
2669** C-x r t (string-rectangle) now deletes the existing rectangle
2670contents before inserting the specified string on each line.
2671
2672** There is a new command delete-whitespace-rectangle
2673which deletes whitespace starting from a particular column
2674in all the lines on a rectangle. The column is specified
2675by the left edge of the rectangle.
2676
2677** You can now store a number into a register with C-u NUMBER C-x r n REG,
2678increment it by INC with C-u INC C-x r + REG (to increment by one, omit
2679C-u INC), and insert it in the buffer with C-x r g REG. This is useful
2680for writing keyboard macros.
2681
2682** The new command M-x speedbar displays a frame in which directories,
2683files, and tags can be displayed, manipulated, and jumped to. The
2684frame defaults to 20 characters in width, and is the same height as
2685the frame that it was started from. Some major modes define
2686additional commands for the speedbar, including Rmail, GUD/GDB, and
2687info.
2688
2689** query-replace-regexp is now bound to C-M-%.
2690
2691** In Transient Mark mode, when the region is active, M-x
2692query-replace and the other replace commands now operate on the region
2693contents only.
2694
2695** M-x write-region, when used interactively, now asks for
2696confirmation before overwriting an existing file. When you call
2697the function from a Lisp program, a new optional argument CONFIRM
2698says whether to ask for confirmation in this case.
2699
2700** If you use find-file-literally and the file is already visited
2701non-literally, the command asks you whether to revisit the file
2702literally. If you say no, it signals an error.
2703
2704** Major modes defined with the "derived mode" feature
2705now use the proper name for the mode hook: WHATEVER-mode-hook.
2706Formerly they used the name WHATEVER-mode-hooks, but that is
2707inconsistent with Emacs conventions.
2708
2709** shell-command-on-region (and shell-command) reports success or
2710failure if the command produces no output.
2711
2712** Set focus-follows-mouse to nil if your window system or window
2713manager does not transfer focus to another window when you just move
2714the mouse.
2715
2716** mouse-menu-buffer-maxlen has been renamed to
2717mouse-buffer-menu-maxlen to be consistent with the other related
2718function and variable names.
2719
2720** The new variable auto-coding-alist specifies coding systems for
2721reading specific files. This has higher priority than
2722file-coding-system-alist.
2723
2724** If you set the variable unibyte-display-via-language-environment to
2725t, then Emacs displays non-ASCII characters are displayed by
2726converting them to the equivalent multibyte characters according to
2727the current language environment. As a result, they are displayed
2728according to the current fontset.
2729
2730** C-q's handling of codes in the range 0200 through 0377 is changed.
2731
2732The codes in the range 0200 through 0237 are inserted as one byte of
2733that code regardless of the values of nonascii-translation-table and
2734nonascii-insert-offset.
2735
2736For the codes in the range 0240 through 0377, if
2737enable-multibyte-characters is non-nil and nonascii-translation-table
2738nor nonascii-insert-offset can't convert them to valid multibyte
2739characters, they are converted to Latin-1 characters.
2740
2741** If you try to find a file that is not read-accessible, you now get
2742an error, rather than an empty buffer and a warning.
2743
2744** In the minibuffer history commands M-r and M-s, an upper case
2745letter in the regular expression forces case-sensitive search.
2746
2747** In the *Help* buffer, cross-references to commands and variables
2748are inferred and hyperlinked. Use C-h m in Help mode for the relevant
2749command keys.
2750
2751** M-x apropos-command, with a prefix argument, no longer looks for
2752user option variables--instead it looks for noninteractive functions.
2753
2754Meanwhile, the command apropos-variable normally searches for
2755user option variables; with a prefix argument, it looks at
2756all variables that have documentation.
2757
2758** When you type a long line in the minibuffer, and the minibuffer
2759shows just one line, automatically scrolling works in a special way
2760that shows you overlap with the previous line of text. The variable
2761minibuffer-scroll-overlap controls how many characters of overlap
2762it should show; the default is 20.
2763
2764Meanwhile, Resize Minibuffer mode is still available; in that mode,
2765the minibuffer grows taller (up to a point) as needed to show the whole
2766of your input.
2767
2768** The new command M-x customize-changed-options lets you customize
2769all the options whose meanings or default values have changed in
2770recent Emacs versions. You specify a previous Emacs version number as
2771argument, and the command creates a customization buffer showing all
2772the customizable options which were changed since that version.
2773Newly added options are included as well.
2774
2775If you don't specify a particular version number argument,
2776then the customization buffer shows all the customizable options
2777for which Emacs versions of changes are recorded.
2778
2779This function is also bound to the Changed Options entry in the
2780Customize menu.
2781
2782** When you run M-x grep with a prefix argument, it figures out
2783the tag around point and puts that into the default grep command.
2784
2785** The new command M-* (pop-tag-mark) pops back through a history of
2786buffer positions from which M-. or other tag-finding commands were
2787invoked.
2788
2789** The new variable comment-padding specifies the number of spaces
2790that `comment-region' will insert before the actual text of the comment.
2791The default is 1.
2792
2793** In Fortran mode the characters `.', `_' and `$' now have symbol
2794syntax, not word syntax. Fortran mode now supports `imenu' and has
2795new commands fortran-join-line (M-^) and fortran-narrow-to-subprogram
2796(C-x n d). M-q can be used to fill a statement or comment block
2797sensibly.
2798
2799** GUD now supports jdb, the Java debugger, and pdb, the Python debugger.
2800
2801** If you set the variable add-log-keep-changes-together to a non-nil
2802value, the command `C-x 4 a' will automatically notice when you make
2803two entries in one day for one file, and combine them.
2804
2805** You can use the command M-x diary-mail-entries to mail yourself a
2806reminder about upcoming diary entries. See the documentation string
2807for a sample shell script for calling this function automatically
2808every night.
2809
2810** All you need to do, to enable use of the Desktop package, is to set
2811the variable desktop-enable to t with Custom.
2812
2813** There is no need to do anything special, now, to enable Gnus to
2814read and post multi-lingual articles.
2815
2816** Outline mode has now support for showing hidden outlines when
2817doing an isearch. In order for this to happen search-invisible should
2818be set to open (the default). If an isearch match is inside a hidden
2819outline the outline is made visible. If you continue pressing C-s and
2820the match moves outside the formerly invisible outline, the outline is
2821made invisible again.
2822
2823** Mail reading and sending changes
2824
2825*** The Rmail e command now switches to displaying the whole header of
2826the message before it lets you edit the message. This is so that any
2827changes you make in the header will not be lost if you subsequently
2828toggle.
2829
2830*** The w command in Rmail, which writes the message body into a file,
2831now works in the summary buffer as well. (The command to delete the
2832summary buffer is now Q.) The default file name for the w command, if
2833the message has no subject, is stored in the variable
2834rmail-default-body-file.
2835
2836*** Most of the commands and modes that operate on mail and netnews no
2837longer depend on the value of mail-header-separator. Instead, they
2838handle whatever separator the buffer happens to use.
2839
2840*** If you set mail-signature to a value which is not t, nil, or a string,
2841it should be an expression. When you send a message, this expression
2842is evaluated to insert the signature.
2843
2844*** The new Lisp library feedmail.el (version 8) enhances processing of
2845outbound email messages. It works in coordination with other email
2846handling packages (e.g., rmail, VM, gnus) and is responsible for
2847putting final touches on messages and actually submitting them for
2848transmission. Users of the emacs program "fakemail" might be
2849especially interested in trying feedmail.
2850
2851feedmail is not enabled by default. See comments at the top of
2852feedmail.el for set-up instructions. Among the bigger features
2853provided by feedmail are:
2854
2855**** you can park outgoing messages into a disk-based queue and
2856stimulate sending some or all of them later (handy for laptop users);
2857there is also a queue for draft messages
2858
2859**** you can get one last look at the prepped outbound message and
2860be prompted for confirmation
2861
2862**** does smart filling of address headers
2863
2864**** can generate a MESSAGE-ID: line and a DATE: line; the date can be
2865the time the message was written or the time it is being sent; this
2866can make FCC copies more closely resemble copies that recipients get
2867
2868**** you can specify an arbitrary function for actually transmitting
2869the message; included in feedmail are interfaces for /bin/[r]mail,
2870/usr/lib/sendmail, and elisp smtpmail; it's easy to write a new
2871function for something else (10-20 lines of elisp)
2872
2873** Dired changes
2874
2875*** The Dired function dired-do-toggle, which toggles marked and unmarked
2876files, is now bound to "t" instead of "T".
2877
2878*** dired-at-point has been added to ffap.el. It allows one to easily
2879run Dired on the directory name at point.
2880
2881*** Dired has a new command: %g. It searches the contents of
2882files in the directory and marks each file that contains a match
2883for a specified regexp.
2884
2885** VC Changes
2886
2887*** New option vc-ignore-vc-files lets you turn off version control
2888conveniently.
2889
2890*** VC Dired has been completely rewritten. It is now much
2891faster, especially for CVS, and works very similar to ordinary
2892Dired.
2893
2894VC Dired is invoked by typing C-x v d and entering the name of the
2895directory to display. By default, VC Dired gives you a recursive
2896listing of all files at or below the given directory which are
2897currently locked (for CVS, all files not up-to-date are shown).
2898
2899You can change the listing format by setting vc-dired-recurse to nil,
2900then it shows only the given directory, and you may also set
2901vc-dired-terse-display to nil, then it shows all files under version
2902control plus the names of any subdirectories, so that you can type `i'
2903on such lines to insert them manually, as in ordinary Dired.
2904
2905All Dired commands operate normally in VC Dired, except for `v', which
2906is redefined as the version control prefix. That means you may type
2907`v l', `v =' etc. to invoke `vc-print-log', `vc-diff' and the like on
2908the file named in the current Dired buffer line. `v v' invokes
2909`vc-next-action' on this file, or on all files currently marked.
2910
2911The new command `v t' (vc-dired-toggle-terse-mode) allows you to
2912toggle between terse display (only locked files) and full display (all
2913VC files plus subdirectories). There is also a special command,
2914`* l', to mark all files currently locked.
2915
2916Giving a prefix argument to C-x v d now does the same thing as in
2917ordinary Dired: it allows you to supply additional options for the ls
2918command in the minibuffer, to fine-tune VC Dired's output.
2919
2920*** Under CVS, if you merge changes from the repository into a working
2921file, and CVS detects conflicts, VC now offers to start an ediff
2922session to resolve them.
2923
2924Alternatively, you can use the new command `vc-resolve-conflicts' to
2925resolve conflicts in a file at any time. It works in any buffer that
2926contains conflict markers as generated by rcsmerge (which is what CVS
2927uses as well).
2928
2929*** You can now transfer changes between branches, using the new
2930command vc-merge (C-x v m). It is implemented for RCS and CVS. When
2931you invoke it in a buffer under version-control, you can specify
2932either an entire branch or a pair of versions, and the changes on that
2933branch or between the two versions are merged into the working file.
2934If this results in any conflicts, they may be resolved interactively,
2935using ediff.
2936
2937** Changes in Font Lock
2938
2939*** The face and variable previously known as font-lock-reference-face
2940are now called font-lock-constant-face to better reflect their typical
2941use for highlighting constants and labels. (Its face properties are
2942unchanged.) The variable font-lock-reference-face remains for now for
2943compatibility reasons, but its value is font-lock-constant-face.
2944
2945** Frame name display changes
2946
2947*** The command set-frame-name lets you set the name of the current
2948frame. You can use the new command select-frame-by-name to select and
2949raise a frame; this is mostly useful on character-only terminals, or
2950when many frames are invisible or iconified.
2951
2952*** On character-only terminal (not a window system), changing the
2953frame name is now reflected on the mode line and in the Buffers/Frames
2954menu.
2955
2956** Comint (subshell) changes
2957
2958*** In Comint modes, the commands to kill, stop or interrupt a
2959subjob now also kill pending input. This is for compatibility
2960with ordinary shells, where the signal characters do this.
2961
2962*** There are new commands in Comint mode.
2963
2964C-c C-x fetches the "next" line from the input history;
2965that is, the line after the last line you got.
2966You can use this command to fetch successive lines, one by one.
2967
2968C-c SPC accumulates lines of input. More precisely, it arranges to
2969send the current line together with the following line, when you send
2970the following line.
2971
2972C-c C-a if repeated twice consecutively now moves to the process mark,
2973which separates the pending input from the subprocess output and the
2974previously sent input.
2975
2976C-c M-r now runs comint-previous-matching-input-from-input;
2977it searches for a previous command, using the current pending input
2978as the search string.
2979
2980*** New option compilation-scroll-output can be set to scroll
2981automatically in compilation-mode windows.
2982
2983** C mode changes
2984
2985*** Multiline macros are now handled, both as they affect indentation,
2986and as recognized syntax. New syntactic symbol cpp-macro-cont is
2987assigned to second and subsequent lines of a multiline macro
2988definition.
2989
2990*** A new style "user" which captures all non-hook-ified
2991(i.e. top-level) .emacs file variable settings and customizations.
2992Style "cc-mode" is an alias for "user" and is deprecated. "gnu"
2993style is still the default however.
2994
2995*** "java" style now conforms to Sun's JDK coding style.
2996
2997*** There are new commands c-beginning-of-defun, c-end-of-defun which
2998are alternatives which you could bind to C-M-a and C-M-e if you prefer
2999them. They do not have key bindings by default.
3000
3001*** New and improved implementations of M-a (c-beginning-of-statement)
3002and M-e (c-end-of-statement).
3003
3004*** C++ namespace blocks are supported, with new syntactic symbols
3005namespace-open, namespace-close, and innamespace.
3006
3007*** File local variable settings of c-file-style and c-file-offsets
3008makes the style variables local to that buffer only.
3009
3010*** New indentation functions c-lineup-close-paren,
3011c-indent-one-line-block, c-lineup-dont-change.
3012
3013*** Improvements (hopefully!) to the way CC Mode is loaded. You
3014should now be able to do a (require 'cc-mode) to get the entire
3015package loaded properly for customization in your .emacs file. A new
3016variable c-initialize-on-load controls this and is t by default.
3017
3018** Changes to hippie-expand.
3019
3020*** New customization variable `hippie-expand-dabbrev-skip-space'. If
3021non-nil, trailing spaces may be included in the abbreviation to search for,
3022which then gives the same behavior as the original `dabbrev-expand'.
3023
3024*** New customization variable `hippie-expand-dabbrev-as-symbol'. If
3025non-nil, characters of syntax '_' is considered part of the word when
3026expanding dynamically.
3027
3028*** New customization variable `hippie-expand-no-restriction'. If
3029non-nil, narrowed buffers are widened before they are searched.
3030
3031*** New customization variable `hippie-expand-only-buffers'. If
3032non-empty, buffers searched are restricted to the types specified in
3033this list. Useful for example when constructing new special-purpose
3034expansion functions with `make-hippie-expand-function'.
3035
3036*** Text properties of the expansion are no longer copied.
3037
3038** Changes in BibTeX mode.
3039
3040*** Any titleword matching a regexp in the new variable
3041bibtex-autokey-titleword-ignore (case sensitive) is ignored during
3042automatic key generation. This replaces variable
3043bibtex-autokey-titleword-first-ignore, which only checked for matches
3044against the first word in the title.
3045
3046*** Autokey generation now uses all words from the title, not just
3047capitalized words. To avoid conflicts with existing customizations,
3048bibtex-autokey-titleword-ignore is set up such that words starting with
3049lowerkey characters will still be ignored. Thus, if you want to use
3050lowercase words from the title, you will have to overwrite the
3051bibtex-autokey-titleword-ignore standard setting.
3052
3053*** Case conversion of names and title words for automatic key
3054generation is more flexible. Variable bibtex-autokey-preserve-case is
3055replaced by bibtex-autokey-titleword-case-convert and
3056bibtex-autokey-name-case-convert.
3057
3058** Changes in vcursor.el.
3059
3060*** Support for character terminals is available: there is a new keymap
3061and the vcursor will appear as an arrow between buffer text. A
3062variable `vcursor-interpret-input' allows input from the vcursor to be
3063entered exactly as if typed. Numerous functions, including
3064`vcursor-compare-windows', have been rewritten to improve consistency
3065in the selection of windows and corresponding keymaps.
3066
3067*** vcursor options can now be altered with M-x customize under the
3068Editing group once the package is loaded.
3069
3070*** Loading vcursor now does not define keys by default, as this is
3071generally a bad side effect. Use M-x customize to set
3072vcursor-key-bindings to t to restore the old behaviour.
3073
3074*** vcursor-auto-disable can be `copy', which turns off copying from the
3075vcursor, but doesn't disable it, after any non-vcursor command.
3076
3077** Ispell changes.
3078
3079*** You can now spell check comments and strings in the current
3080buffer with M-x ispell-comments-and-strings. Comments and strings
3081are identified by syntax tables in effect.
3082
3083*** Generic region skipping implemented.
3084A single buffer can be broken into a number of regions where text will
3085and will not be checked. The definitions of the regions can be user
3086defined. New applications and improvements made available by this
3087include:
3088
3089 o URLs are automatically skipped
3090 o EMail message checking is vastly improved.
3091
3092*** Ispell can highlight the erroneous word even on non-window terminals.
3093
3094** Changes to RefTeX mode
3095
3096RefTeX has been updated in order to make it more usable with very
3097large projects (like a several volume math book). The parser has been
3098re-written from scratch. To get maximum speed from RefTeX, check the
3099section `Optimizations' in the manual.
3100
3101*** New recursive parser.
3102
3103The old version of RefTeX created a single large buffer containing the
3104entire multifile document in order to parse the document. The new
3105recursive parser scans the individual files.
3106
3107*** Parsing only part of a document.
3108
3109Reparsing of changed document parts can now be made faster by enabling
3110partial scans. To use this feature, read the documentation string of
3111the variable `reftex-enable-partial-scans' and set the variable to t.
3112
3113 (setq reftex-enable-partial-scans t)
3114
3115*** Storing parsing information in a file.
3116
3117This can improve startup times considerably. To turn it on, use
3118
3119 (setq reftex-save-parse-info t)
3120
3121*** Using multiple selection buffers
3122
3123If the creation of label selection buffers is too slow (this happens
3124for large documents), you can reuse these buffers by setting
3125
3126 (setq reftex-use-multiple-selection-buffers t)
3127
3128*** References to external documents.
3129
3130The LaTeX package `xr' allows to cross-reference labels in external
3131documents. RefTeX can provide information about the external
3132documents as well. To use this feature, set up the \externaldocument
3133macros required by the `xr' package and rescan the document with
3134RefTeX. The external labels can then be accessed with the `x' key in
3135the selection buffer provided by `reftex-reference' (bound to `C-c )').
3136The `x' key also works in the table of contents buffer.
3137
3138*** Many more labeled LaTeX environments are recognized by default.
3139
3140The builtin command list now covers all the standard LaTeX commands,
3141and all of the major packages included in the LaTeX distribution.
3142
3143Also, RefTeX now understands the \appendix macro and changes
3144the enumeration of sections in the *toc* buffer accordingly.
3145
3146*** Mouse support for selection and *toc* buffers
3147
3148The mouse can now be used to select items in the selection and *toc*
3149buffers. See also the new option `reftex-highlight-selection'.
3150
3151*** New keymaps for selection and table of contents modes.
3152
3153The selection processes for labels and citation keys, and the table of
3154contents buffer now have their own keymaps: `reftex-select-label-map',
3155`reftex-select-bib-map', `reftex-toc-map'. The selection processes
3156have a number of new keys predefined. In particular, TAB lets you
3157enter a label with completion. Check the on-the-fly help (press `?'
3158at the selection prompt) or read the Info documentation to find out
3159more.
3160
3161*** Support for the varioref package
3162
3163The `v' key in the label selection buffer toggles \ref versus \vref.
3164
3165*** New hooks
3166
3167Three new hooks can be used to redefine the way labels, references,
3168and citations are created. These hooks are
3169`reftex-format-label-function', `reftex-format-ref-function',
3170`reftex-format-cite-function'.
3171
3172*** Citations outside LaTeX
3173
3174The command `reftex-citation' may also be used outside LaTeX (e.g. in
3175a mail buffer). See the Info documentation for details.
3176
3177*** Short context is no longer fontified.
3178
3179The short context in the label menu no longer copies the
3180fontification from the text in the buffer. If you prefer it to be
3181fontified, use
3182
3183 (setq reftex-refontify-context t)
3184
3185** file-cache-minibuffer-complete now accepts a prefix argument.
3186With a prefix argument, it does not try to do completion of
3187the file name within its directory; it only checks for other
3188directories that contain the same file name.
3189
3190Thus, given the file name Makefile, and assuming that a file
3191Makefile.in exists in the same directory, ordinary
3192file-cache-minibuffer-complete will try to complete Makefile to
3193Makefile.in and will therefore never look for other directories that
3194have Makefile. A prefix argument tells it not to look for longer
3195names such as Makefile.in, so that instead it will look for other
3196directories--just as if the name were already complete in its present
3197directory.
3198
3199** New modes and packages
3200
3201*** There is a new alternative major mode for Perl, Cperl mode.
3202It has many more features than Perl mode, and some people prefer
3203it, but some do not.
3204
3205*** There is a new major mode, M-x vhdl-mode, for editing files of VHDL
3206code.
3207
3208*** M-x which-function-mode enables a minor mode that displays the
3209current function name continuously in the mode line, as you move
3210around in a buffer.
3211
3212Which Function mode is effective in major modes which support Imenu.
3213
3214*** Gametree is a major mode for editing game analysis trees. The author
3215uses it for keeping notes about his postal Chess games, but it should
3216be helpful for other two-player games as well, as long as they have an
3217established system of notation similar to Chess.
3218
3219*** The new minor mode checkdoc-minor-mode provides Emacs Lisp
3220documentation string checking for style and spelling. The style
3221guidelines are found in the Emacs Lisp programming manual.
3222
3223*** The net-utils package makes some common networking features
3224available in Emacs. Some of these functions are wrappers around
3225system utilities (ping, nslookup, etc); others are implementations of
3226simple protocols (finger, whois) in Emacs Lisp. There are also
3227functions to make simple connections to TCP/IP ports for debugging and
3228the like.
3229
3230*** highlight-changes-mode is a minor mode that uses colors to
3231identify recently changed parts of the buffer text.
3232
3233*** The new package `midnight' lets you specify things to be done
3234within Emacs at midnight--by default, kill buffers that you have not
3235used in a considerable time. To use this feature, customize
3236the user option `midnight-mode' to t.
3237
3238*** The file generic-x.el defines a number of simple major modes.
3239
3240 apache-generic-mode: For Apache and NCSA httpd configuration files
3241 samba-generic-mode: Samba configuration files
3242 fvwm-generic-mode: For fvwm initialization files
3243 x-resource-generic-mode: For X resource files
3244 hosts-generic-mode: For hosts files (.rhosts, /etc/hosts, etc)
3245 mailagent-rules-generic-mode: For mailagent .rules files
3246 javascript-generic-mode: For JavaScript files
3247 vrml-generic-mode: For VRML files
3248 java-manifest-generic-mode: For Java MANIFEST files
3249 java-properties-generic-mode: For Java property files
3250 mailrc-generic-mode: For .mailrc files
3251
3252 Platform-specific modes:
3253
3254 prototype-generic-mode: For Solaris/Sys V prototype files
3255 pkginfo-generic-mode: For Solaris/Sys V pkginfo files
3256 alias-generic-mode: For C shell alias files
3257 inf-generic-mode: For MS-Windows INF files
3258 ini-generic-mode: For MS-Windows INI files
3259 reg-generic-mode: For MS-Windows Registry files
3260 bat-generic-mode: For MS-Windows BAT scripts
3261 rc-generic-mode: For MS-Windows Resource files
3262 rul-generic-mode: For InstallShield scripts
3263\f
3264* Lisp changes in Emacs 20.3 since the Emacs Lisp Manual was published
3265
3266** If you want a Lisp file to be read in unibyte mode,
3267use -*-unibyte: t;-*- on its first line.
3268That will force Emacs to read that file in unibyte mode.
3269Otherwise, the file will be loaded and byte-compiled in multibyte mode.
3270
3271Thus, each lisp file is read in a consistent way regardless of whether
3272you started Emacs with --unibyte, so that a Lisp program gives
3273consistent results regardless of how Emacs was started.
3274
3275** The new function assoc-default is useful for searching an alist,
3276and using a default value if the key is not found there. You can
3277specify a comparison predicate, so this function is useful for
3278searching comparing a string against an alist of regular expressions.
3279
3280** The functions unibyte-char-to-multibyte and
3281multibyte-char-to-unibyte convert between unibyte and multibyte
3282character codes, in a way that is appropriate for the current language
3283environment.
3284
3285** The functions read-event, read-char and read-char-exclusive now
3286take two optional arguments. PROMPT, if non-nil, specifies a prompt
3287string. SUPPRESS-INPUT-METHOD, if non-nil, says to disable the
3288current input method for reading this one event.
3289
3290** Two new variables print-escape-nonascii and print-escape-multibyte
3291now control whether to output certain characters as
3292backslash-sequences. print-escape-nonascii applies to single-byte
3293non-ASCII characters; print-escape-multibyte applies to multibyte
3294characters. Both of these variables are used only when printing
3295in readable fashion (prin1 uses them, princ does not).
3296\f
3297* Lisp changes in Emacs 20.3 before the Emacs Lisp Manual was published
3298
3299** Compiled Emacs Lisp files made with the modified "MBSK" version
3300of Emacs 20.2 do not work in Emacs 20.3.
3301
3302** Buffer positions are now measured in characters, as they were
3303in Emacs 19 and before. This means that (forward-char 1)
3304always increases point by 1.
3305
3306The function chars-in-region now just subtracts its arguments. It is
3307considered obsolete. The function char-boundary-p has been deleted.
3308
3309See below for additional changes relating to multibyte characters.
3310
3311** defcustom, defface and defgroup now accept the keyword `:version'.
3312Use this to specify in which version of Emacs a certain variable's
3313default value changed. For example,
3314
3315 (defcustom foo-max 34 "*Maximum number of foo's allowed."
3316 :type 'integer
3317 :group 'foo
3318 :version "20.3")
3319
3320 (defgroup foo-group nil "The foo group."
3321 :version "20.3")
3322
3323If an entire new group is added or the variables in it have the
3324default values changed, then just add a `:version' to that group. It
3325is recommended that new packages added to the distribution contain a
3326`:version' in the top level group.
3327
3328This information is used to control the customize-changed-options command.
3329
3330** It is now an error to change the value of a symbol whose name
3331starts with a colon--if it is interned in the standard obarray.
3332
3333However, setting such a symbol to its proper value, which is that
3334symbol itself, is not an error. This is for the sake of programs that
3335support previous Emacs versions by explicitly setting these variables
3336to themselves.
3337
3338If you set the variable keyword-symbols-constant-flag to nil,
3339this error is suppressed, and you can set these symbols to any
3340values whatever.
3341
3342** There is a new debugger command, R.
3343It evaluates an expression like e, but saves the result
3344in the buffer *Debugger-record*.
3345
3346** Frame-local variables.
3347
3348You can now make a variable local to various frames. To do this, call
3349the function make-variable-frame-local; this enables frames to have
3350local bindings for that variable.
3351
3352These frame-local bindings are actually frame parameters: you create a
3353frame-local binding in a specific frame by calling
3354modify-frame-parameters and specifying the variable name as the
3355parameter name.
3356
3357Buffer-local bindings take precedence over frame-local bindings.
3358Thus, if the current buffer has a buffer-local binding, that binding is
3359active; otherwise, if the selected frame has a frame-local binding,
3360that binding is active; otherwise, the default binding is active.
3361
3362It would not be hard to implement window-local bindings, but it is not
3363clear that this would be very useful; windows tend to come and go in a
3364very transitory fashion, so that trying to produce any specific effect
3365through a window-local binding would not be very robust.
3366
3367** `sregexq' and `sregex' are two new functions for constructing
3368"symbolic regular expressions." These are Lisp expressions that, when
3369evaluated, yield conventional string-based regexps. The symbolic form
3370makes it easier to construct, read, and maintain complex patterns.
3371See the documentation in sregex.el.
3372
3373** parse-partial-sexp's return value has an additional element which
3374is used to pass information along if you pass it to another call to
3375parse-partial-sexp, starting its scan where the first call ended.
3376The contents of this field are not yet finalized.
3377
3378** eval-region now accepts a fourth optional argument READ-FUNCTION.
3379If it is non-nil, that function is used instead of `read'.
3380
3381** unload-feature by default removes the feature's functions from
3382known hooks to avoid trouble, but a package providing FEATURE can
3383define a hook FEATURE-unload-hook to be run by unload-feature instead.
3384
3385** read-from-minibuffer no longer returns the argument DEFAULT-VALUE
3386when the user enters empty input. It now returns the null string, as
3387it did in Emacs 19. The default value is made available in the
3388history via M-n, but it is not applied here as a default.
3389
3390The other, more specialized minibuffer-reading functions continue to
3391return the default value (not the null string) when the user enters
3392empty input.
3393
3394** The new variable read-buffer-function controls which routine to use
3395for selecting buffers. For example, if you set this variable to
3396`iswitchb-read-buffer', iswitchb will be used to read buffer names.
3397Other functions can also be used if they accept the same arguments as
3398`read-buffer' and return the selected buffer name as a string.
3399
3400** The new function read-passwd reads a password from the terminal,
3401echoing a period for each character typed. It takes three arguments:
3402a prompt string, a flag which says "read it twice to make sure", and a
3403default password to use if the user enters nothing.
3404
3405** The variable fill-nobreak-predicate gives major modes a way to
3406specify not to break a line at certain places. Its value is a
3407function which is called with no arguments, with point located at the
3408place where a break is being considered. If the function returns
3409non-nil, then the line won't be broken there.
3410
3411** window-end now takes an optional second argument, UPDATE.
3412If this is non-nil, then the function always returns an accurate
3413up-to-date value for the buffer position corresponding to the
3414end of the window, even if this requires computation.
3415
3416** other-buffer now takes an optional argument FRAME
3417which specifies which frame's buffer list to use.
3418If it is nil, that means use the selected frame's buffer list.
3419
3420** The new variable buffer-display-time, always local in every buffer,
3421holds the value of (current-time) as of the last time that a window
3422was directed to display this buffer.
3423
3424** It is now meaningful to compare two window-configuration objects
3425with `equal'. Two window-configuration objects are equal if they
3426describe equivalent arrangements of windows, in the same frame--in
3427other words, if they would give the same results if passed to
3428set-window-configuration.
3429
3430** compare-window-configurations is a new function that compares two
3431window configurations loosely. It ignores differences in saved buffer
3432positions and scrolling, and considers only the structure and sizes of
3433windows and the choice of buffers to display.
3434
3435** The variable minor-mode-overriding-map-alist allows major modes to
3436override the key bindings of a minor mode. The elements of this alist
3437look like the elements of minor-mode-map-alist: (VARIABLE . KEYMAP).
3438
3439If the VARIABLE in an element of minor-mode-overriding-map-alist has a
3440non-nil value, the paired KEYMAP is active, and totally overrides the
3441map (if any) specified for the same variable in minor-mode-map-alist.
3442
3443minor-mode-overriding-map-alist is automatically local in all buffers,
3444and it is meant to be set by major modes.
3445
3446** The function match-string-no-properties is like match-string
3447except that it discards all text properties from the result.
3448
3449** The function load-average now accepts an optional argument
3450USE-FLOATS. If it is non-nil, the load average values are returned as
3451floating point numbers, rather than as integers to be divided by 100.
3452
3453** The new variable temporary-file-directory specifies the directory
3454to use for creating temporary files. The default value is determined
3455in a reasonable way for your operating system; on GNU and Unix systems
3456it is based on the TMP and TMPDIR environment variables.
3457
3458** Menu changes
3459
3460*** easymenu.el now uses the new menu item format and supports the
3461keywords :visible and :filter. The existing keyword :keys is now
3462better supported.
3463
3464The variable `easy-menu-precalculate-equivalent-keybindings' controls
3465a new feature which calculates keyboard equivalents for the menu when
3466you define the menu. The default is t. If you rarely use menus, you
3467can set the variable to nil to disable this precalculation feature;
3468then the calculation is done only if you use the menu bar.
3469
3470*** A new format for menu items is supported.
3471
3472In a keymap, a key binding that has the format
3473 (STRING . REAL-BINDING) or (STRING HELP-STRING . REAL-BINDING)
3474defines a menu item. Now a menu item definition may also be a list that
3475starts with the symbol `menu-item'.
3476
3477The format is:
3478 (menu-item ITEM-NAME) or
3479 (menu-item ITEM-NAME REAL-BINDING . ITEM-PROPERTY-LIST)
3480where ITEM-NAME is an expression which evaluates to the menu item
3481string, and ITEM-PROPERTY-LIST has the form of a property list.
3482The supported properties include
3483
3484:enable FORM Evaluate FORM to determine whether the
3485 item is enabled.
3486:visible FORM Evaluate FORM to determine whether the
3487 item should appear in the menu.
3488:filter FILTER-FN
3489 FILTER-FN is a function of one argument,
3490 which will be REAL-BINDING.
3491 It should return a binding to use instead.
3492:keys DESCRIPTION
3493 DESCRIPTION is a string that describes an equivalent keyboard
3494 binding for for REAL-BINDING. DESCRIPTION is expanded with
3495 `substitute-command-keys' before it is used.
3496:key-sequence KEY-SEQUENCE
3497 KEY-SEQUENCE is a key-sequence for an equivalent
3498 keyboard binding.
3499:key-sequence nil
3500 This means that the command normally has no
3501 keyboard equivalent.
3502:help HELP HELP is the extra help string (not currently used).
3503:button (TYPE . SELECTED)
3504 TYPE is :toggle or :radio.
3505 SELECTED is a form, to be evaluated, and its
3506 value says whether this button is currently selected.
3507
3508Buttons are at the moment only simulated by prefixes in the menu.
3509Eventually ordinary X-buttons may be supported.
3510
3511(menu-item ITEM-NAME) defines unselectable item.
3512
3513** New event types
3514
3515*** The new event type `mouse-wheel' is generated by a wheel on a
3516mouse (such as the MS Intellimouse). The event contains a delta that
3517corresponds to the amount and direction that the wheel is rotated,
3518which is typically used to implement a scroll or zoom. The format is:
3519
3520 (mouse-wheel POSITION DELTA)
3521
3522where POSITION is a list describing the position of the event in the
3523same format as a mouse-click event, and DELTA is a signed number
3524indicating the number of increments by which the wheel was rotated. A
3525negative DELTA indicates that the wheel was rotated backwards, towards
3526the user, and a positive DELTA indicates that the wheel was rotated
3527forward, away from the user.
3528
3529As of now, this event type is generated only on MS Windows.
3530
3531*** The new event type `drag-n-drop' is generated when a group of
3532files is selected in an application outside of Emacs, and then dragged
3533and dropped onto an Emacs frame. The event contains a list of
3534filenames that were dragged and dropped, which are then typically
3535loaded into Emacs. The format is:
3536
3537 (drag-n-drop POSITION FILES)
3538
3539where POSITION is a list describing the position of the event in the
3540same format as a mouse-click event, and FILES is the list of filenames
3541that were dragged and dropped.
3542
3543As of now, this event type is generated only on MS Windows.
3544
3545** Changes relating to multibyte characters.
3546
3547*** The variable enable-multibyte-characters is now read-only;
3548any attempt to set it directly signals an error. The only way
3549to change this value in an existing buffer is with set-buffer-multibyte.
3550
3551*** In a string constant, `\ ' now stands for "nothing at all". You
3552can use it to terminate a hex escape which is followed by a character
3553that could otherwise be read as part of the hex escape.
3554
3555*** String indices are now measured in characters, as they were
3556in Emacs 19 and before.
3557
3558The function chars-in-string has been deleted.
3559The function concat-chars has been renamed to `string'.
3560
3561*** The function set-buffer-multibyte sets the flag in the current
3562buffer that says whether the buffer uses multibyte representation or
3563unibyte representation. If the argument is nil, it selects unibyte
3564representation. Otherwise it selects multibyte representation.
3565
3566This function does not change the contents of the buffer, viewed
3567as a sequence of bytes. However, it does change the contents
3568viewed as characters; a sequence of two bytes which is treated as
3569one character when the buffer uses multibyte representation
3570will count as two characters using unibyte representation.
3571
3572This function sets enable-multibyte-characters to record which
3573representation is in use. It also adjusts various data in the buffer
3574(including its markers, overlays and text properties) so that they are
3575consistent with the new representation.
3576
3577*** string-make-multibyte takes a string and converts it to multibyte
3578representation. Most of the time, you don't need to care
3579about the representation, because Emacs converts when necessary;
3580however, it makes a difference when you compare strings.
3581
3582The conversion of non-ASCII characters works by adding the value of
3583nonascii-insert-offset to each character, or by translating them
3584using the table nonascii-translation-table.
3585
3586*** string-make-unibyte takes a string and converts it to unibyte
3587representation. Most of the time, you don't need to care about the
3588representation, but it makes a difference when you compare strings.
3589
3590The conversion from multibyte to unibyte representation
3591loses information; the only time Emacs performs it automatically
3592is when inserting a multibyte string into a unibyte buffer.
3593
3594*** string-as-multibyte takes a string, and returns another string
3595which contains the same bytes, but treats them as multibyte.
3596
3597*** string-as-unibyte takes a string, and returns another string
3598which contains the same bytes, but treats them as unibyte.
3599
3600*** The new function compare-strings lets you compare
3601portions of two strings. Unibyte strings are converted to multibyte,
3602so that a unibyte string can match a multibyte string.
3603You can specify whether to ignore case or not.
3604
3605*** assoc-ignore-case now uses compare-strings so that
3606it can treat unibyte and multibyte strings as equal.
3607
3608*** Regular expression operations and buffer string searches now
3609convert the search pattern to multibyte or unibyte to accord with the
3610buffer or string being searched.
3611
3612One consequence is that you cannot always use \200-\377 inside of
3613[...] to match all non-ASCII characters. This does still work when
3614searching or matching a unibyte buffer or string, but not when
3615searching or matching a multibyte string. Unfortunately, there is no
3616obvious choice of syntax to use within [...] for that job. But, what
3617you want is just to match all non-ASCII characters, the regular
3618expression [^\0-\177] works for it.
3619
3620*** Structure of coding system changed.
3621
3622All coding systems (including aliases and subsidiaries) are named
3623by symbols; the symbol's `coding-system' property is a vector
3624which defines the coding system. Aliases share the same vector
3625as the principal name, so that altering the contents of this
3626vector affects the principal name and its aliases. You can define
3627your own alias name of a coding system by the function
3628define-coding-system-alias.
3629
3630The coding system definition includes a property list of its own. Use
3631the new functions `coding-system-get' and `coding-system-put' to
3632access such coding system properties as post-read-conversion,
3633pre-write-conversion, character-translation-table-for-decode,
3634character-translation-table-for-encode, mime-charset, and
3635safe-charsets. For instance, (coding-system-get 'iso-latin-1
3636'mime-charset) gives the corresponding MIME-charset parameter
3637`iso-8859-1'.
3638
3639Among the coding system properties listed above, safe-charsets is new.
3640The value of this property is a list of character sets which this
3641coding system can correctly encode and decode. For instance:
3642(coding-system-get 'iso-latin-1 'safe-charsets) => (ascii latin-iso8859-1)
3643
3644Here, "correctly encode" means that the encoded character sets can
3645also be handled safely by systems other than Emacs as far as they
3646are capable of that coding system. Though, Emacs itself can encode
3647the other character sets and read it back correctly.
3648
3649*** The new function select-safe-coding-system can be used to find a
3650proper coding system for encoding the specified region or string.
3651This function requires a user interaction.
3652
3653*** The new functions find-coding-systems-region and
3654find-coding-systems-string are helper functions used by
3655select-safe-coding-system. They return a list of all proper coding
3656systems to encode a text in some region or string. If you don't want
3657a user interaction, use one of these functions instead of
3658select-safe-coding-system.
3659
3660*** The explicit encoding and decoding functions, such as
3661decode-coding-region and encode-coding-string, now set
3662last-coding-system-used to reflect the actual way encoding or decoding
3663was done.
3664
3665*** The new function detect-coding-with-language-environment can be
3666used to detect a coding system of text according to priorities of
3667coding systems used by some specific language environment.
3668
3669*** The functions detect-coding-region and detect-coding-string always
3670return a list if the arg HIGHEST is nil. Thus, if only ASCII
3671characters are found, they now return a list of single element
3672`undecided' or its subsidiaries.
3673
3674*** The new functions coding-system-change-eol-conversion and
3675coding-system-change-text-conversion can be used to get a different
3676coding system than what specified only in how end-of-line or text is
3677converted.
3678
3679*** The new function set-selection-coding-system can be used to set a
3680coding system for communicating with other X clients.
3681
3682*** The function `map-char-table' now passes as argument only valid
3683character codes, plus generic characters that stand for entire
3684character sets or entire subrows of a character set. In other words,
3685each time `map-char-table' calls its FUNCTION argument, the key value
3686either will be a valid individual character code, or will stand for a
3687range of characters.
3688
3689*** The new function `char-valid-p' can be used for checking whether a
3690Lisp object is a valid character code or not.
3691
3692*** The new function `charset-after' returns a charset of a character
3693in the current buffer at position POS.
3694
3695*** Input methods are now implemented using the variable
3696input-method-function. If this is non-nil, its value should be a
3697function; then, whenever Emacs reads an input event that is a printing
3698character with no modifier bits, it calls that function, passing the
3699event as an argument. Often this function will read more input, first
3700binding input-method-function to nil.
3701
3702The return value should be a list of the events resulting from input
3703method processing. These events will be processed sequentially as
3704input, before resorting to unread-command-events. Events returned by
3705the input method function are not passed to the input method function,
3706not even if they are printing characters with no modifier bits.
3707
3708The input method function is not called when reading the second and
3709subsequent events of a key sequence.
3710
3711*** You can customize any language environment by using
3712set-language-environment-hook and exit-language-environment-hook.
3713
3714The hook `exit-language-environment-hook' should be used to undo
3715customizations that you made with set-language-environment-hook. For
3716instance, if you set up a special key binding for a specific language
3717environment by set-language-environment-hook, you should set up
3718exit-language-environment-hook to restore the normal key binding.
3719\f
3720* Changes in Emacs 20.1
3721
3722** Emacs has a new facility for customization of its many user
3723options. It is called M-x customize. With this facility you can look
3724at the many user options in an organized way; they are grouped into a
3725tree structure.
3726
3727M-x customize also knows what sorts of values are legitimate for each
3728user option and ensures that you don't use invalid values.
3729
3730With M-x customize, you can set options either for the present Emacs
3731session or permanently. (Permanent settings are stored automatically
3732in your .emacs file.)
3733
3734** Scroll bars are now on the left side of the window.
3735You can change this with M-x customize-option scroll-bar-mode.
3736
3737** The mode line no longer includes the string `Emacs'.
3738This makes more space in the mode line for other information.
3739
3740** When you select a region with the mouse, it is highlighted
3741immediately afterward. At that time, if you type the DELETE key, it
3742kills the region.
3743
3744The BACKSPACE key, and the ASCII character DEL, do not do this; they
3745delete the character before point, as usual.
3746
3747** In an incremental search the whole current match is highlighted
3748on terminals which support this. (You can disable this feature
3749by setting search-highlight to nil.)
3750
3751** In the minibuffer, in some cases, you can now use M-n to
3752insert the default value into the minibuffer as text. In effect,
3753the default value (if the minibuffer routines know it) is tacked
3754onto the history "in the future". (The more normal use of the
3755history list is to use M-p to insert minibuffer input used in the
3756past.)
3757
3758** In Text mode, now only blank lines separate paragraphs.
3759This makes it possible to get the full benefit of Adaptive Fill mode
3760in Text mode, and other modes derived from it (such as Mail mode).
3761TAB in Text mode now runs the command indent-relative; this
3762makes a practical difference only when you use indented paragraphs.
3763
3764As a result, the old Indented Text mode is now identical to Text mode,
3765and is an alias for it.
3766
3767If you want spaces at the beginning of a line to start a paragraph,
3768use the new mode, Paragraph Indent Text mode.
3769
3770** Scrolling changes
3771
3772*** Scroll commands to scroll a whole screen now preserve the screen
3773position of the cursor, if scroll-preserve-screen-position is non-nil.
3774
3775In this mode, if you scroll several screens back and forth, finishing
3776on the same screen where you started, the cursor goes back to the line
3777where it started.
3778
3779*** If you set scroll-conservatively to a small number, then when you
3780move point a short distance off the screen, Emacs will scroll the
3781screen just far enough to bring point back on screen, provided that
3782does not exceed `scroll-conservatively' lines.
3783
3784*** The new variable scroll-margin says how close point can come to the
3785top or bottom of a window. It is a number of screen lines; if point
3786comes within that many lines of the top or bottom of the window, Emacs
3787recenters the window.
3788
3789** International character set support (MULE)
3790
3791Emacs now supports a wide variety of international character sets,
3792including European variants of the Latin alphabet, as well as Chinese,
3793Devanagari (Hindi and Marathi), Ethiopian, Greek, IPA, Japanese,
3794Korean, Lao, Russian, Thai, Tibetan, and Vietnamese scripts. These
3795features have been merged from the modified version of Emacs known as
3796MULE (for "MULti-lingual Enhancement to GNU Emacs")
3797
3798Users of these scripts have established many more-or-less standard
3799coding systems for storing files. Emacs uses a single multibyte
3800character encoding within Emacs buffers; it can translate from a wide
3801variety of coding systems when reading a file and can translate back
3802into any of these coding systems when saving a file.
3803
3804Keyboards, even in the countries where these character sets are used,
3805generally don't have keys for all the characters in them. So Emacs
3806supports various "input methods", typically one for each script or
3807language, to make it possible to type them.
3808
3809The Emacs internal multibyte encoding represents a non-ASCII
3810character as a sequence of bytes in the range 0200 through 0377.
3811
3812The new prefix key C-x RET is used for commands that pertain
3813to multibyte characters, coding systems, and input methods.
3814
3815You can disable multibyte character support as follows:
3816
3817 (setq-default enable-multibyte-characters nil)
3818
3819Calling the function standard-display-european turns off multibyte
3820characters, unless you specify a non-nil value for the second
3821argument, AUTO. This provides compatibility for people who are
3822already using standard-display-european to continue using unibyte
3823characters for their work until they want to change.
3824
3825*** Input methods
3826
3827An input method is a kind of character conversion which is designed
3828specifically for interactive input. In Emacs, typically each language
3829has its own input method (though sometimes several languages which use
3830the same characters can share one input method). Some languages
3831support several input methods.
3832
3833The simplest kind of input method works by mapping ASCII letters into
3834another alphabet. This is how the Greek and Russian input methods
3835work.
3836
3837A more powerful technique is composition: converting sequences of
3838characters into one letter. Many European input methods use
3839composition to produce a single non-ASCII letter from a sequence which
3840consists of a letter followed by diacritics. For example, a' is one
3841sequence of two characters that might be converted into a single
3842letter.
3843
3844The input methods for syllabic scripts typically use mapping followed
3845by conversion. The input methods for Thai and Korean work this way.
3846First, letters are mapped into symbols for particular sounds or tone
3847marks; then, sequences of these which make up a whole syllable are
3848mapped into one syllable sign--most often a "composite character".
3849
3850None of these methods works very well for Chinese and Japanese, so
3851they are handled specially. First you input a whole word using
3852phonetic spelling; then, after the word is in the buffer, Emacs
3853converts it into one or more characters using a large dictionary.
3854
3855Since there is more than one way to represent a phonetically spelled
3856word using Chinese characters, Emacs can only guess which one to use;
3857typically these input methods give you a way to say "guess again" if
3858the first guess is wrong.
3859
3860*** The command C-x RET m (toggle-enable-multibyte-characters)
3861turns multibyte character support on or off for the current buffer.
3862
3863If multibyte character support is turned off in a buffer, then each
3864byte is a single character, even codes 0200 through 0377--exactly as
3865they did in Emacs 19.34. This includes the features for support for
3866the European characters, ISO Latin-1 and ISO Latin-2.
3867
3868However, there is no need to turn off multibyte character support to
3869use ISO Latin-1 or ISO Latin-2; the Emacs multibyte character set
3870includes all the characters in these character sets, and Emacs can
3871translate automatically to and from either one.
3872
3873*** Visiting a file in unibyte mode.
3874
3875Turning off multibyte character support in the buffer after visiting a
3876file with multibyte code conversion will display the multibyte
3877sequences already in the buffer, byte by byte. This is probably not
3878what you want.
3879
3880If you want to edit a file of unibyte characters (Latin-1, for
3881example), you can do it by specifying `no-conversion' as the coding
3882system when reading the file. This coding system also turns off
3883multibyte characters in that buffer.
3884
3885If you turn off multibyte character support entirely, this turns off
3886character conversion as well.
3887
3888*** Displaying international characters on X Windows.
3889
3890A font for X typically displays just one alphabet or script.
3891Therefore, displaying the entire range of characters Emacs supports
3892requires using many fonts.
3893
3894Therefore, Emacs now supports "fontsets". Each fontset is a
3895collection of fonts, each assigned to a range of character codes.
3896
3897A fontset has a name, like a font. Individual fonts are defined by
3898the X server; fontsets are defined within Emacs itself. But once you
3899have defined a fontset, you can use it in a face or a frame just as
3900you would use a font.
3901
3902If a fontset specifies no font for a certain character, or if it
3903specifies a font that does not exist on your system, then it cannot
3904display that character. It will display an empty box instead.
3905
3906The fontset height and width are determined by the ASCII characters
3907(that is, by the font in the fontset which is used for ASCII
3908characters). If another font in the fontset has a different height,
3909or the wrong width, then characters assigned to that font are clipped,
3910and displayed within a box if highlight-wrong-size-font is non-nil.
3911
3912*** Defining fontsets.
3913
3914Emacs does not use any fontset by default. Its default font is still
3915chosen as in previous versions. You can tell Emacs to use a fontset
3916with the `-fn' option or the `Font' X resource.
3917
3918Emacs creates a standard fontset automatically according to the value
3919of standard-fontset-spec. This fontset's short name is
3920`fontset-standard'. Bold, italic, and bold-italic variants of the
3921standard fontset are created automatically.
3922
3923If you specify a default ASCII font with the `Font' resource or `-fn'
3924argument, a fontset is generated from it. This works by replacing the
3925FOUNDARY, FAMILY, ADD_STYLE, and AVERAGE_WIDTH fields of the font name
3926with `*' then using this to specify a fontset. This fontset's short
3927name is `fontset-startup'.
3928
3929Emacs checks resources of the form Fontset-N where N is 0, 1, 2...
3930The resource value should have this form:
3931 FONTSET-NAME, [CHARSET-NAME:FONT-NAME]...
3932FONTSET-NAME should have the form of a standard X font name, except:
3933 * most fields should be just the wild card "*".
3934 * the CHARSET_REGISTRY field should be "fontset"
3935 * the CHARSET_ENCODING field can be any nickname of the fontset.
3936The construct CHARSET-NAME:FONT-NAME can be repeated any number
3937of times; each time specifies the font for one character set.
3938CHARSET-NAME should be the name name of a character set, and
3939FONT-NAME should specify an actual font to use for that character set.
3940
3941Each of these fontsets has an alias which is made from the
3942last two font name fields, CHARSET_REGISTRY and CHARSET_ENCODING.
3943You can refer to the fontset by that alias or by its full name.
3944
3945For any character sets that you don't mention, Emacs tries to choose a
3946font by substituting into FONTSET-NAME. For instance, with the
3947following resource,
3948 Emacs*Fontset-0: -*-fixed-medium-r-normal-*-24-*-*-*-*-*-fontset-24
3949the font for ASCII is generated as below:
3950 -*-fixed-medium-r-normal-*-24-*-ISO8859-1
3951Here is the substitution rule:
3952 Change CHARSET_REGISTRY and CHARSET_ENCODING to that of the charset
3953 defined in the variable x-charset-registries. For instance, ASCII has
3954 the entry (ascii . "ISO8859-1") in this variable. Then, reduce
3955 sequences of wild cards -*-...-*- with a single wildcard -*-.
3956 (This is to prevent use of auto-scaled fonts.)
3957
3958The function which processes the fontset resource value to create the
3959fontset is called create-fontset-from-fontset-spec. You can also call
3960that function explicitly to create a fontset.
3961
3962With the X resource Emacs.Font, you can specify a fontset name just
3963like an actual font name. But be careful not to specify a fontset
3964name in a wildcard resource like Emacs*Font--that tries to specify the
3965fontset for other purposes including menus, and they cannot handle
3966fontsets.
3967
3968*** The command M-x set-language-environment sets certain global Emacs
3969defaults for a particular choice of language.
3970
3971Selecting a language environment typically specifies a default input
3972method and which coding systems to recognize automatically when
3973visiting files. However, it does not try to reread files you have
3974already visited; the text in those buffers is not affected. The
3975language environment may also specify a default choice of coding
3976system for new files that you create.
3977
3978It makes no difference which buffer is current when you use
3979set-language-environment, because these defaults apply globally to the
3980whole Emacs session.
3981
3982For example, M-x set-language-environment RET Latin-1 RET
3983chooses the Latin-1 character set. In the .emacs file, you can do this
3984with (set-language-environment "Latin-1").
3985
3986*** The command C-x RET f (set-buffer-file-coding-system)
3987specifies the file coding system for the current buffer. This
3988specifies what sort of character code translation to do when saving
3989the file. As an argument, you must specify the name of one of the
3990coding systems that Emacs supports.
3991
3992*** The command C-x RET c (universal-coding-system-argument)
3993lets you specify a coding system when you read or write a file.
3994This command uses the minibuffer to read a coding system name.
3995After you exit the minibuffer, the specified coding system
3996is used for *the immediately following command*.
3997
3998So if the immediately following command is a command to read or
3999write a file, it uses the specified coding system for that file.
4000
4001If the immediately following command does not use the coding system,
4002then C-x RET c ultimately has no effect.
4003
4004For example, C-x RET c iso-8859-1 RET C-x C-f temp RET
4005visits the file `temp' treating it as ISO Latin-1.
4006
4007*** You can specify the coding system for a file using the -*-
4008construct. Include `coding: CODINGSYSTEM;' inside the -*-...-*-
4009to specify use of coding system CODINGSYSTEM. You can also
4010specify the coding system in a local variable list at the end
4011of the file.
4012
4013*** The command C-x RET t (set-terminal-coding-system) specifies
4014the coding system for terminal output. If you specify a character
4015code for terminal output, all characters output to the terminal are
4016translated into that character code.
4017
4018This feature is useful for certain character-only terminals built in
4019various countries to support the languages of those countries.
4020
4021By default, output to the terminal is not translated at all.
4022
4023*** The command C-x RET k (set-keyboard-coding-system) specifies
4024the coding system for keyboard input.
4025
4026Character code translation of keyboard input is useful for terminals
4027with keys that send non-ASCII graphic characters--for example,
4028some terminals designed for ISO Latin-1 or subsets of it.
4029
4030By default, keyboard input is not translated at all.
4031
4032Character code translation of keyboard input is similar to using an
4033input method, in that both define sequences of keyboard input that
4034translate into single characters. However, input methods are designed
4035to be convenient for interactive use, while the code translations are
4036designed to work with terminals.
4037
4038*** The command C-x RET p (set-buffer-process-coding-system)
4039specifies the coding system for input and output to a subprocess.
4040This command applies to the current buffer; normally, each subprocess
4041has its own buffer, and thus you can use this command to specify
4042translation to and from a particular subprocess by giving the command
4043in the corresponding buffer.
4044
4045By default, process input and output are not translated at all.
4046
4047*** The variable file-name-coding-system specifies the coding system
4048to use for encoding file names before operating on them.
4049It is also used for decoding file names obtained from the system.
4050
4051*** The command C-\ (toggle-input-method) activates or deactivates
4052an input method. If no input method has been selected before, the
4053command prompts for you to specify the language and input method you
4054want to use.
4055
4056C-u C-\ (select-input-method) lets you switch to a different input
4057method. C-h C-\ (or C-h I) describes the current input method.
4058
4059*** Some input methods remap the keyboard to emulate various keyboard
4060layouts commonly used for particular scripts. How to do this
4061remapping properly depends on your actual keyboard layout. To specify
4062which layout your keyboard has, use M-x quail-set-keyboard-layout.
4063
4064*** The command C-h C (describe-coding-system) displays
4065the coding systems currently selected for various purposes, plus
4066related information.
4067
4068*** The command C-h h (view-hello-file) displays a file called
4069HELLO, which has examples of text in many languages, using various
4070scripts.
4071
4072*** The command C-h L (describe-language-support) displays
4073information about the support for a particular language.
4074You specify the language as an argument.
4075
4076*** The mode line now contains a letter or character that identifies
4077the coding system used in the visited file. It normally follows the
4078first dash.
4079
4080A dash indicates the default state of affairs: no code conversion
4081(except CRLF => newline if appropriate). `=' means no conversion
4082whatsoever. The ISO 8859 coding systems are represented by digits
40831 through 9. Other coding systems are represented by letters:
4084
4085 A alternativnyj (Russian)
4086 B big5 (Chinese)
4087 C cn-gb-2312 (Chinese)
4088 C iso-2022-cn (Chinese)
4089 D in-is13194-devanagari (Indian languages)
4090 E euc-japan (Japanese)
4091 I iso-2022-cjk or iso-2022-ss2 (Chinese, Japanese, Korean)
4092 J junet (iso-2022-7) or old-jis (iso-2022-jp-1978-irv) (Japanese)
4093 K euc-korea (Korean)
4094 R koi8 (Russian)
4095 Q tibetan
4096 S shift_jis (Japanese)
4097 T lao
4098 T tis620 (Thai)
4099 V viscii or vscii (Vietnamese)
4100 i iso-2022-lock (Chinese, Japanese, Korean)
4101 k iso-2022-kr (Korean)
4102 v viqr (Vietnamese)
4103 z hz (Chinese)
4104
4105When you are using a character-only terminal (not a window system),
4106two additional characters appear in between the dash and the file
4107coding system. These two characters describe the coding system for
4108keyboard input, and the coding system for terminal output.
4109
4110*** The new variable rmail-file-coding-system specifies the code
4111conversion to use for RMAIL files. The default value is nil.
4112
4113When you read mail with Rmail, each message is decoded automatically
4114into Emacs' internal format. This has nothing to do with
4115rmail-file-coding-system. That variable controls reading and writing
4116Rmail files themselves.
4117
4118*** The new variable sendmail-coding-system specifies the code
4119conversion for outgoing mail. The default value is nil.
4120
4121Actually, there are three different ways of specifying the coding system
4122for sending mail:
4123
4124- If you use C-x RET f in the mail buffer, that takes priority.
4125- Otherwise, if you set sendmail-coding-system non-nil, that specifies it.
4126- Otherwise, the default coding system for new files is used,
4127 if that is non-nil. That comes from your language environment.
4128- Otherwise, Latin-1 is used.
4129
4130*** The command C-h t (help-with-tutorial) accepts a prefix argument
4131to specify the language for the tutorial file. Currently, English,
4132Japanese, Korean and Thai are supported. We welcome additional
4133translations.
4134
4135** An easy new way to visit a file with no code or format conversion
4136of any kind: Use M-x find-file-literally. There is also a command
4137insert-file-literally which inserts a file into the current buffer
4138without any conversion.
4139
4140** C-q's handling of octal character codes is changed.
4141You can now specify any number of octal digits.
4142RET terminates the digits and is discarded;
4143any other non-digit terminates the digits and is then used as input.
4144
4145** There are new commands for looking up Info documentation for
4146functions, variables and file names used in your programs.
4147
4148Type M-x info-lookup-symbol to look up a symbol in the buffer at point.
4149Type M-x info-lookup-file to look up a file in the buffer at point.
4150
4151Precisely which Info files are used to look it up depends on the major
4152mode. For example, in C mode, the GNU libc manual is used.
4153
4154** M-TAB in most programming language modes now runs the command
4155complete-symbol. This command performs completion on the symbol name
4156in the buffer before point.
4157
4158With a numeric argument, it performs completion based on the set of
4159symbols documented in the Info files for the programming language that
4160you are using.
4161
4162With no argument, it does completion based on the current tags tables,
4163just like the old binding of M-TAB (complete-tag).
4164
4165** File locking works with NFS now.
4166
4167The lock file for FILENAME is now a symbolic link named .#FILENAME,
4168in the same directory as FILENAME.
4169
4170This means that collision detection between two different machines now
4171works reasonably well; it also means that no file server or directory
4172can become a bottleneck.
4173
4174The new method does have drawbacks. It means that collision detection
4175does not operate when you edit a file in a directory where you cannot
4176create new files. Collision detection also doesn't operate when the
4177file server does not support symbolic links. But these conditions are
4178rare, and the ability to have collision detection while using NFS is
4179so useful that the change is worth while.
4180
4181When Emacs or a system crashes, this may leave behind lock files which
4182are stale. So you may occasionally get warnings about spurious
4183collisions. When you determine that the collision is spurious, just
4184tell Emacs to go ahead anyway.
4185
4186** If you wish to use Show Paren mode to display matching parentheses,
4187it is no longer sufficient to load paren.el. Instead you must call
4188show-paren-mode.
4189
4190** If you wish to use Delete Selection mode to replace a highlighted
4191selection when you insert new text, it is no longer sufficient to load
4192delsel.el. Instead you must call the function delete-selection-mode.
4193
4194** If you wish to use Partial Completion mode to complete partial words
4195within symbols or filenames, it is no longer sufficient to load
4196complete.el. Instead you must call the function partial-completion-mode.
4197
4198** If you wish to use uniquify to rename buffers for you,
4199it is no longer sufficient to load uniquify.el. You must also
4200set uniquify-buffer-name-style to one of the non-nil legitimate values.
4201
4202** Changes in View mode.
4203
4204*** Several new commands are available in View mode.
4205Do H in view mode for a list of commands.
4206
4207*** There are two new commands for entering View mode:
4208view-file-other-frame and view-buffer-other-frame.
4209
4210*** Exiting View mode does a better job of restoring windows to their
4211previous state.
4212
4213*** New customization variable view-scroll-auto-exit. If non-nil,
4214scrolling past end of buffer makes view mode exit.
4215
4216*** New customization variable view-exits-all-viewing-windows. If
4217non-nil, view-mode will at exit restore all windows viewing buffer,
4218not just the selected window.
4219
4220*** New customization variable view-read-only. If non-nil, visiting a
4221read-only file automatically enters View mode, and toggle-read-only
4222turns View mode on or off.
4223
4224*** New customization variable view-remove-frame-by-deleting controls
4225how to remove a not needed frame at view mode exit. If non-nil,
4226delete the frame, if nil make an icon of it.
4227
4228** C-x v l, the command to print a file's version control log,
4229now positions point at the entry for the file's current branch version.
4230
4231** C-x v =, the command to compare a file with the last checked-in version,
4232has a new feature. If the file is currently not locked, so that it is
4233presumably identical to the last checked-in version, the command now asks
4234which version to compare with.
4235
4236** When using hideshow.el, incremental search can temporarily show hidden
4237blocks if a match is inside the block.
4238
4239The block is hidden again if the search is continued and the next match
4240is outside the block. By customizing the variable
4241isearch-hide-immediately you can choose to hide all the temporarily
4242shown blocks only when exiting from incremental search.
4243
4244By customizing the variable hs-isearch-open you can choose what kind
4245of blocks to temporarily show during isearch: comment blocks, code
4246blocks, all of them or none.
4247
4248** The new command C-x 4 0 (kill-buffer-and-window) kills the
4249current buffer and deletes the selected window. It asks for
4250confirmation first.
4251
4252** C-x C-w, which saves the buffer into a specified file name,
4253now changes the major mode according to that file name.
4254However, the mode will not be changed if
4255(1) a local variables list or the `-*-' line specifies a major mode, or
4256(2) the current major mode is a "special" mode,
4257 not suitable for ordinary files, or
4258(3) the new file name does not particularly specify any mode.
4259
4260This applies to M-x set-visited-file-name as well.
4261
4262However, if you set change-major-mode-with-file-name to nil, then
4263these commands do not change the major mode.
4264
4265** M-x occur changes.
4266
4267*** If the argument to M-x occur contains upper case letters,
4268it performs a case-sensitive search.
4269
4270*** In the *Occur* buffer made by M-x occur,
4271if you type g or M-x revert-buffer, this repeats the search
4272using the same regular expression and the same buffer as before.
4273
4274** In Transient Mark mode, the region in any one buffer is highlighted
4275in just one window at a time. At first, it is highlighted in the
4276window where you set the mark. The buffer's highlighting remains in
4277that window unless you select to another window which shows the same
4278buffer--then the highlighting moves to that window.
4279
4280** The feature to suggest key bindings when you use M-x now operates
4281after the command finishes. The message suggesting key bindings
4282appears temporarily in the echo area. The previous echo area contents
4283come back after a few seconds, in case they contain useful information.
4284
4285** Each frame now independently records the order for recently
4286selected buffers, so that the default for C-x b is now based on the
4287buffers recently selected in the selected frame.
4288
4289** Outline mode changes.
4290
4291*** Outline mode now uses overlays (this is the former noutline.el).
4292
4293*** Incremental searches skip over invisible text in Outline mode.
4294
4295** When a minibuffer window is active but not the selected window, if
4296you try to use the minibuffer, you used to get a nested minibuffer.
4297Now, this not only gives an error, it also cancels the minibuffer that
4298was already active.
4299
4300The motive for this change is so that beginning users do not
4301unknowingly move away from minibuffers, leaving them active, and then
4302get confused by it.
4303
4304If you want to be able to have recursive minibuffers, you must
4305set enable-recursive-minibuffers to non-nil.
4306
4307** Changes in dynamic abbrevs.
4308
4309*** Expanding dynamic abbrevs with M-/ is now smarter about case
4310conversion. If the expansion has mixed case not counting the first
4311character, and the abbreviation matches the beginning of the expansion
4312including case, then the expansion is copied verbatim.
4313
4314The expansion is also copied verbatim if the abbreviation itself has
4315mixed case. And using SPC M-/ to copy an additional word always
4316copies it verbatim except when the previous copied word is all caps.
4317
4318*** The values of `dabbrev-case-replace' and `dabbrev-case-fold-search'
4319are no longer Lisp expressions. They have simply three possible
4320values.
4321
4322`dabbrev-case-replace' has these three values: nil (don't preserve
4323case), t (do), or `case-replace' (do like M-x query-replace).
4324`dabbrev-case-fold-search' has these three values: nil (don't ignore
4325case), t (do), or `case-fold-search' (do like search).
4326
4327** Minibuffer history lists are truncated automatically now to a
4328certain length. The variable history-length specifies how long they
4329can be. The default value is 30.
4330
4331** Changes in Mail mode.
4332
4333*** The key C-x m no longer runs the `mail' command directly.
4334Instead, it runs the command `compose-mail', which invokes the mail
4335composition mechanism you have selected with the variable
4336`mail-user-agent'. The default choice of user agent is
4337`sendmail-user-agent', which gives behavior compatible with the old
4338behavior.
4339
4340C-x 4 m now runs compose-mail-other-window, and C-x 5 m runs
4341compose-mail-other-frame.
4342
4343*** While composing a reply to a mail message, from Rmail, you can use
4344the command C-c C-r to cite just the region from the message you are
4345replying to. This copies the text which is the selected region in the
4346buffer that shows the original message.
4347
4348*** The command C-c C-i inserts a file at the end of the message,
4349with separator lines around the contents.
4350
4351*** The command M-x expand-mail-aliases expands all mail aliases
4352in suitable mail headers. Emacs automatically extracts mail alias
4353definitions from your mail alias file (e.g., ~/.mailrc). You do not
4354need to expand mail aliases yourself before sending mail.
4355
4356*** New features in the mail-complete command.
4357
4358**** The mail-complete command now inserts the user's full name,
4359for local users or if that is known. The variable mail-complete-style
4360controls the style to use, and whether to do this at all.
4361Its values are like those of mail-from-style.
4362
4363**** The variable mail-passwd-command lets you specify a shell command
4364to run to fetch a set of password-entries that add to the ones in
4365/etc/passwd.
4366
4367**** The variable mail-passwd-file now specifies a list of files to read
4368to get the list of user ids. By default, one file is used:
4369/etc/passwd.
4370
4371** You can "quote" a file name to inhibit special significance of
4372special syntax, by adding `/:' to the beginning. Thus, if you have a
4373directory named `/foo:', you can prevent it from being treated as a
4374reference to a remote host named `foo' by writing it as `/:/foo:'.
4375
4376Emacs uses this new construct automatically when necessary, such as
4377when you start it with a working directory whose name might otherwise
4378be taken to be magic.
4379
4380** There is a new command M-x grep-find which uses find to select
4381files to search through, and grep to scan them. The output is
4382available in a Compile mode buffer, as with M-x grep.
4383
4384M-x grep now uses the -e option if the grep program supports that.
4385(-e prevents problems if the search pattern starts with a dash.)
4386
4387** In Dired, the & command now flags for deletion the files whose names
4388suggest they are probably not needed in the long run.
4389
4390In Dired, * is now a prefix key for mark-related commands.
4391
4392new key dired.el binding old key
4393------- ---------------- -------
4394 * c dired-change-marks c
4395 * m dired-mark m
4396 * * dired-mark-executables * (binding deleted)
4397 * / dired-mark-directories / (binding deleted)
4398 * @ dired-mark-symlinks @ (binding deleted)
4399 * u dired-unmark u
4400 * DEL dired-unmark-backward DEL
4401 * ? dired-unmark-all-files M-C-?
4402 * ! dired-unmark-all-marks
4403 * % dired-mark-files-regexp % m
4404 * C-n dired-next-marked-file M-}
4405 * C-p dired-prev-marked-file M-{
4406
4407** Rmail changes.
4408
4409*** When Rmail cannot convert your incoming mail into Babyl format, it
4410saves the new mail in the file RMAILOSE.n, where n is an integer
4411chosen to make a unique name. This way, Rmail will not keep crashing
4412each time you run it.
4413
4414*** In Rmail, the variable rmail-summary-line-count-flag now controls
4415whether to include the line count in the summary. Non-nil means yes.
4416
4417*** In Rmail summary buffers, d and C-d (the commands to delete
4418messages) now take repeat counts as arguments. A negative argument
4419means to move in the opposite direction.
4420
4421*** In Rmail, the t command now takes an optional argument which lets
4422you specify whether to show the message headers in full or pruned.
4423
4424*** In Rmail, the new command w (rmail-output-body-to-file) writes
4425just the body of the current message into a file, without the headers.
4426It takes the file name from the message subject, by default, but you
4427can edit that file name in the minibuffer before it is actually used
4428for output.
4429
4430** Gnus changes.
4431
4432*** nntp.el has been totally rewritten in an asynchronous fashion.
4433
4434*** Article prefetching functionality has been moved up into
4435Gnus.
4436
4437*** Scoring can now be performed with logical operators like
4438`and', `or', `not', and parent redirection.
4439
4440*** Article washing status can be displayed in the
4441article mode line.
4442
4443*** gnus.el has been split into many smaller files.
4444
4445*** Suppression of duplicate articles based on Message-ID.
4446
4447(setq gnus-suppress-duplicates t)
4448
4449*** New variables for specifying what score and adapt files
4450are to be considered home score and adapt files. See
4451`gnus-home-score-file' and `gnus-home-adapt-files'.
4452
4453*** Groups can inherit group parameters from parent topics.
4454
4455*** Article editing has been revamped and is now usable.
4456
4457*** Signatures can be recognized in more intelligent fashions.
4458See `gnus-signature-separator' and `gnus-signature-limit'.
4459
4460*** Summary pick mode has been made to look more nn-like.
4461Line numbers are displayed and the `.' command can be
4462used to pick articles.
4463
4464*** Commands for moving the .newsrc.eld from one server to
4465another have been added.
4466
4467 `M-x gnus-change-server'
4468
4469*** A way to specify that "uninteresting" fields be suppressed when
4470generating lines in buffers.
4471
4472*** Several commands in the group buffer can be undone with
4473`M-C-_'.
4474
4475*** Scoring can be done on words using the new score type `w'.
4476
4477*** Adaptive scoring can be done on a Subject word-by-word basis:
4478
4479 (setq gnus-use-adaptive-scoring '(word))
4480
4481*** Scores can be decayed.
4482
4483 (setq gnus-decay-scores t)
4484
4485*** Scoring can be performed using a regexp on the Date header. The
4486Date is normalized to compact ISO 8601 format first.
4487
4488*** A new command has been added to remove all data on articles from
4489the native server.
4490
4491 `M-x gnus-group-clear-data-on-native-groups'
4492
4493*** A new command for reading collections of documents
4494(nndoc with nnvirtual on top) has been added -- `M-C-d'.
4495
4496*** Process mark sets can be pushed and popped.
4497
4498*** A new mail-to-news backend makes it possible to post
4499even when the NNTP server doesn't allow posting.
4500
4501*** A new backend for reading searches from Web search engines
4502(DejaNews, Alta Vista, InReference) has been added.
4503
4504 Use the `G w' command in the group buffer to create such
4505 a group.
4506
4507*** Groups inside topics can now be sorted using the standard
4508sorting functions, and each topic can be sorted independently.
4509
4510 See the commands under the `T S' submap.
4511
4512*** Subsets of the groups can be sorted independently.
4513
4514 See the commands under the `G P' submap.
4515
4516*** Cached articles can be pulled into the groups.
4517
4518 Use the `Y c' command.
4519
4520*** Score files are now applied in a more reliable order.
4521
4522*** Reports on where mail messages end up can be generated.
4523
4524 `M-x nnmail-split-history'
4525
4526*** More hooks and functions have been added to remove junk
4527from incoming mail before saving the mail.
4528
4529 See `nnmail-prepare-incoming-header-hook'.
4530
4531*** The nnml mail backend now understands compressed article files.
4532
4533*** To enable Gnus to read/post multi-lingual articles, you must execute
4534the following code, for instance, in your .emacs.
4535
4536 (add-hook 'gnus-startup-hook 'gnus-mule-initialize)
4537
4538Then, when you start Gnus, it will decode non-ASCII text automatically
4539and show appropriate characters. (Note: if you are using gnus-mime
4540from the SEMI package, formerly known as TM, you should NOT add this
4541hook to gnus-startup-hook; gnus-mime has its own method of handling
4542this issue.)
4543
4544Since it is impossible to distinguish all coding systems
4545automatically, you may need to specify a choice of coding system for a
4546particular news group. This can be done by:
4547
4548 (gnus-mule-add-group NEWSGROUP 'CODING-SYSTEM)
4549
4550Here NEWSGROUP should be a string which names a newsgroup or a tree
4551of newsgroups. If NEWSGROUP is "XXX.YYY", all news groups under
4552"XXX.YYY" (including "XXX.YYY.ZZZ") will use the specified coding
4553system. CODING-SYSTEM specifies which coding system to use (for both
4554for reading and posting).
4555
4556CODING-SYSTEM can also be a cons cell of the form
4557 (READ-CODING-SYSTEM . POST-CODING-SYSTEM)
4558Then READ-CODING-SYSTEM is used when you read messages from the
4559newsgroups, while POST-CODING-SYSTEM is used when you post messages
4560there.
4561
4562Emacs knows the right coding systems for certain newsgroups by
4563default. Here are some of these default settings:
4564
4565 (gnus-mule-add-group "fj" 'iso-2022-7)
4566 (gnus-mule-add-group "alt.chinese.text" 'hz-gb-2312)
4567 (gnus-mule-add-group "alt.hk" 'hz-gb-2312)
4568 (gnus-mule-add-group "alt.chinese.text.big5" 'cn-big5)
4569 (gnus-mule-add-group "soc.culture.vietnamese" '(nil . viqr))
4570
4571When you reply by mail to an article, these settings are ignored;
4572the mail is encoded according to sendmail-coding-system, as usual.
4573
4574** CC mode changes.
4575
4576*** If you edit primarily one style of C (or C++, Objective-C, Java)
4577code, you may want to make the CC Mode style variables have global
4578values so that you can set them directly in your .emacs file. To do
4579this, set c-style-variables-are-local-p to nil in your .emacs file.
4580Note that this only takes effect if you do it *before* cc-mode.el is
4581loaded.
4582
4583If you typically edit more than one style of C (or C++, Objective-C,
4584Java) code in a single Emacs session, you may want to make the CC Mode
4585style variables have buffer local values. By default, all buffers
4586share the same style variable settings; to make them buffer local, set
4587c-style-variables-are-local-p to t in your .emacs file. Note that you
4588must do this *before* CC Mode is loaded.
4589
4590*** The new variable c-indentation-style holds the C style name
4591of the current buffer.
4592
4593*** The variable c-block-comments-indent-p has been deleted, because
4594it is no longer necessary. C mode now handles all the supported styles
4595of block comments, with no need to say which one you will use.
4596
4597*** There is a new indentation style "python", which specifies the C
4598style that the Python developers like.
4599
4600*** There is a new c-cleanup-list option: brace-elseif-brace.
4601This says to put ...} else if (...) {... on one line,
4602just as brace-else-brace says to put ...} else {... on one line.
4603
4604** VC Changes [new]
4605
4606** In vc-retrieve-snapshot (C-x v r), if you don't specify a snapshot
4607name, it retrieves the *latest* versions of all files in the current
4608directory and its subdirectories (aside from files already locked).
4609
4610This feature is useful if your RCS directory is a link to a common
4611master directory, and you want to pick up changes made by other
4612developers.
4613
4614You can do the same thing for an individual file by typing C-u C-x C-q
4615RET in a buffer visiting that file.
4616
4617*** VC can now handle files under CVS that are being "watched" by
4618other developers. Such files are made read-only by CVS. To get a
4619writable copy, type C-x C-q in a buffer visiting such a file. VC then
4620calls "cvs edit", which notifies the other developers of it.
4621
4622*** vc-version-diff (C-u C-x v =) now suggests reasonable defaults for
4623version numbers, based on the current state of the file.
4624
4625** Calendar changes.
4626
4627A new function, list-holidays, allows you list holidays or subclasses
4628of holidays for ranges of years. Related menu items allow you do this
4629for the year of the selected date, or the following/previous years.
4630
4631** ps-print changes
4632
4633There are some new user variables for customizing the page layout.
4634
4635*** Paper size, paper orientation, columns
4636
4637The variable `ps-paper-type' determines the size of paper ps-print
4638formats for; it should contain one of the symbols:
4639`a4' `a3' `letter' `legal' `letter-small' `tabloid'
4640`ledger' `statement' `executive' `a4small' `b4' `b5'
4641It defaults to `letter'.
4642If you need other sizes, see the variable `ps-page-dimensions-database'.
4643
4644The variable `ps-landscape-mode' determines the orientation
4645of the printing on the page. nil, the default, means "portrait" mode,
4646non-nil means "landscape" mode.
4647
4648The variable `ps-number-of-columns' must be a positive integer.
4649It determines the number of columns both in landscape and portrait mode.
4650It defaults to 1.
4651
4652*** Horizontal layout
4653
4654The horizontal layout is determined by the variables
4655`ps-left-margin', `ps-inter-column', and `ps-right-margin'.
4656All are measured in points.
4657
4658*** Vertical layout
4659
4660The vertical layout is determined by the variables
4661`ps-bottom-margin', `ps-top-margin', and `ps-header-offset'.
4662All are measured in points.
4663
4664*** Headers
4665
4666If the variable `ps-print-header' is nil, no header is printed. Then
4667`ps-header-offset' is not relevant and `ps-top-margin' represents the
4668margin above the text.
4669
4670If the variable `ps-print-header-frame' is non-nil, a gaudy
4671framing box is printed around the header.
4672
4673The contents of the header are determined by `ps-header-lines',
4674`ps-show-n-of-n', `ps-left-header' and `ps-right-header'.
4675
4676The height of the header is determined by `ps-header-line-pad',
4677`ps-header-font-family', `ps-header-title-font-size' and
4678`ps-header-font-size'.
4679
4680*** Font managing
4681
4682The variable `ps-font-family' determines which font family is to be
4683used for ordinary text. Its value must be a key symbol in the alist
4684`ps-font-info-database'. You can add other font families by adding
4685elements to this alist.
4686
4687The variable `ps-font-size' determines the size of the font
4688for ordinary text. It defaults to 8.5 points.
4689
4690** hideshow changes.
4691
4692*** now supports hiding of blocks of single line comments (like // for
4693C++, ; for lisp).
4694
4695*** Support for java-mode added.
4696
4697*** When doing `hs-hide-all' it is now possible to also hide the comments
4698in the file if `hs-hide-comments-when-hiding-all' is set.
4699
4700*** The new function `hs-hide-initial-comment' hides the the comments at
4701the beginning of the files. Finally those huge RCS logs don't stay in your
4702way! This is run by default when entering the `hs-minor-mode'.
4703
4704*** Now uses overlays instead of `selective-display', so is more
4705robust and a lot faster.
4706
4707*** A block beginning can span multiple lines.
4708
4709*** The new variable `hs-show-hidden-short-form' if t, directs hideshow
4710to show only the beginning of a block when it is hidden. See the
4711documentation for more details.
4712
4713** Changes in Enriched mode.
4714
4715*** When you visit a file in enriched-mode, Emacs will make sure it is
4716filled to the current fill-column. This behavior is now independent
4717of the size of the window. When you save the file, the fill-column in
4718use is stored as well, so that the whole buffer need not be refilled
4719the next time unless the fill-column is different.
4720
4721*** use-hard-newlines is now a minor mode. When it is enabled, Emacs
4722distinguishes between hard and soft newlines, and treats hard newlines
4723as paragraph boundaries. Otherwise all newlines inserted are marked
4724as soft, and paragraph boundaries are determined solely from the text.
4725
4726** Font Lock mode
4727
4728*** Custom support
4729
4730The variables font-lock-face-attributes, font-lock-display-type and
4731font-lock-background-mode are now obsolete; the recommended way to specify the
4732faces to use for Font Lock mode is with M-x customize-group on the new custom
4733group font-lock-highlighting-faces. If you set font-lock-face-attributes in
4734your ~/.emacs file, Font Lock mode will respect its value. However, you should
4735consider converting from setting that variable to using M-x customize.
4736
4737You can still use X resources to specify Font Lock face appearances.
4738
4739*** Maximum decoration
4740
4741Fontification now uses the maximum level of decoration supported by
4742default. Previously, fontification used a mode-specific default level
4743of decoration, which is typically the minimum level of decoration
4744supported. You can set font-lock-maximum-decoration to nil
4745to get the old behavior.
4746
4747*** New support
4748
4749Support is now provided for Java, Objective-C, AWK and SIMULA modes.
4750
4751Note that Font Lock mode can be turned on without knowing exactly what modes
4752support Font Lock mode, via the command global-font-lock-mode.
4753
4754*** Configurable support
4755
4756Support for C, C++, Objective-C and Java can be more easily configured for
4757additional types and classes via the new variables c-font-lock-extra-types,
4758c++-font-lock-extra-types, objc-font-lock-extra-types and, you guessed it,
4759java-font-lock-extra-types. These value of each of these variables should be a
4760list of regexps matching the extra type names. For example, the default value
4761of c-font-lock-extra-types is ("\\sw+_t") which means fontification follows the
4762convention that C type names end in _t. This results in slower fontification.
4763
4764Of course, you can change the variables that specify fontification in whatever
4765way you wish, typically by adding regexps. However, these new variables make
4766it easier to make specific and common changes for the fontification of types.
4767
4768*** Adding highlighting patterns to existing support
4769
4770You can use the new function font-lock-add-keywords to add your own
4771highlighting patterns, such as for project-local or user-specific constructs,
4772for any mode.
4773
4774For example, to highlight `FIXME:' words in C comments, put:
4775
4776 (font-lock-add-keywords 'c-mode '(("\\<FIXME:" 0 font-lock-warning-face t)))
4777
4778in your ~/.emacs.
4779
4780*** New faces
4781
4782Font Lock now defines two new faces, font-lock-builtin-face and
4783font-lock-warning-face. These are intended to highlight builtin keywords,
4784distinct from a language's normal keywords, and objects that should be brought
4785to user attention, respectively. Various modes now use these new faces.
4786
4787*** Changes to fast-lock support mode
4788
4789The fast-lock package, one of the two Font Lock support modes, can now process
4790cache files silently. You can use the new variable fast-lock-verbose, in the
4791same way as font-lock-verbose, to control this feature.
4792
4793*** Changes to lazy-lock support mode
4794
4795The lazy-lock package, one of the two Font Lock support modes, can now fontify
4796according to the true syntactic context relative to other lines. You can use
4797the new variable lazy-lock-defer-contextually to control this feature. If
4798non-nil, changes to the buffer will cause subsequent lines in the buffer to be
4799refontified after lazy-lock-defer-time seconds of idle time. If nil, then only
4800the modified lines will be refontified; this is the same as the previous Lazy
4801Lock mode behaviour and the behaviour of Font Lock mode.
4802
4803This feature is useful in modes where strings or comments can span lines.
4804For example, if a string or comment terminating character is deleted, then if
4805this feature is enabled subsequent lines in the buffer will be correctly
4806refontified to reflect their new syntactic context. Previously, only the line
4807containing the deleted character would be refontified and you would have to use
4808the command M-g M-g (font-lock-fontify-block) to refontify some lines.
4809
4810As a consequence of this new feature, two other variables have changed:
4811
4812Variable `lazy-lock-defer-driven' is renamed `lazy-lock-defer-on-scrolling'.
4813Variable `lazy-lock-defer-time' can now only be a time, i.e., a number.
4814Buffer modes for which on-the-fly deferral applies can be specified via the
4815new variable `lazy-lock-defer-on-the-fly'.
4816
4817If you set these variables in your ~/.emacs, then you may have to change those
4818settings.
4819
4820** Ada mode changes.
4821
4822*** There is now better support for using find-file.el with Ada mode.
4823If you switch between spec and body, the cursor stays in the same
4824procedure (modulo overloading). If a spec has no body file yet, but
4825you try to switch to its body file, Ada mode now generates procedure
4826stubs.
4827
4828*** There are two new commands:
4829 - `ada-make-local' : invokes gnatmake on the current buffer
4830 - `ada-check-syntax' : check syntax of current buffer.
4831
4832The user options `ada-compiler-make', `ada-make-options',
4833`ada-language-version', `ada-compiler-syntax-check', and
4834`ada-compile-options' are used within these commands.
4835
4836*** Ada mode can now work with Outline minor mode. The outline level
4837is calculated from the indenting, not from syntactic constructs.
4838Outlining does not work if your code is not correctly indented.
4839
4840*** The new function `ada-gnat-style' converts the buffer to the style of
4841formatting used in GNAT. It places two blanks after a comment start,
4842places one blank between a word end and an opening '(', and puts one
4843space between a comma and the beginning of a word.
4844
4845** Scheme mode changes.
4846
4847*** Scheme mode indentation now uses many of the facilities of Lisp
4848mode; therefore, the variables to customize it are the variables used
4849for Lisp mode which have names starting with `lisp-'. The variables
4850with names starting with `scheme-' which used to do this no longer
4851have any effect.
4852
4853If you want to use different indentation for Scheme and Lisp, this is
4854still possible, but now you must do it by adding a hook to
4855scheme-mode-hook, which could work by setting the `lisp-' indentation
4856variables as buffer-local variables.
4857
4858*** DSSSL mode is a variant of Scheme mode, for editing DSSSL scripts.
4859Use M-x dsssl-mode.
4860
4861** The emacsclient program now accepts an option --no-wait which tells
4862it to return immediately without waiting for you to "finish" the
4863buffer in Emacs.
4864
4865** M-x eldoc-mode enables a minor mode in which the echo area
4866constantly shows the parameter list for function being called at point
4867(in Emacs Lisp and Lisp Interaction modes only).
4868
4869** C-x n d now runs the new command narrow-to-defun,
4870which narrows the accessible parts of the buffer to just
4871the current defun.
4872
4873** Emacs now handles the `--' argument in the standard way; all
4874following arguments are treated as ordinary file names.
4875
4876** On MSDOS and Windows, the bookmark file is now called _emacs.bmk,
4877and the saved desktop file is now called _emacs.desktop (truncated if
4878necessary).
4879
4880** When you kill a buffer that visits a file,
4881if there are any registers that save positions in the file,
4882these register values no longer become completely useless.
4883If you try to go to such a register with C-x j, then you are
4884asked whether to visit the file again. If you say yes,
4885it visits the file and then goes to the same position.
4886
4887** When you visit a file that changes frequently outside Emacs--for
4888example, a log of output from a process that continues to run--it may
4889be useful for Emacs to revert the file without querying you whenever
4890you visit the file afresh with C-x C-f.
4891
4892You can request this behavior for certain files by setting the
4893variable revert-without-query to a list of regular expressions. If a
4894file's name matches any of these regular expressions, find-file and
4895revert-buffer revert the buffer without asking for permission--but
4896only if you have not edited the buffer text yourself.
4897
4898** set-default-font has been renamed to set-frame-font
4899since it applies only to the current frame.
4900
4901** In TeX mode, you can use the variable tex-main-file to specify the
4902file for tex-file to run TeX on. (By default, tex-main-file is nil,
4903and tex-file runs TeX on the current visited file.)
4904
4905This is useful when you are editing a document that consists of
4906multiple files. In each of the included files, you can set up a local
4907variable list which specifies the top-level file of your document for
4908tex-main-file. Then tex-file will run TeX on the whole document
4909instead of just the file you are editing.
4910
4911** RefTeX mode
4912
4913RefTeX mode is a new minor mode with special support for \label, \ref
4914and \cite macros in LaTeX documents. RefTeX distinguishes labels of
4915different environments (equation, figure, ...) and has full support for
4916multifile documents. To use it, select a buffer with a LaTeX document and
4917turn the mode on with M-x reftex-mode. Here are the main user commands:
4918
4919C-c ( reftex-label
4920 Creates a label semi-automatically. RefTeX is context sensitive and
4921 knows which kind of label is needed.
4922
4923C-c ) reftex-reference
4924 Offers in a menu all labels in the document, along with context of the
4925 label definition. The selected label is referenced as \ref{LABEL}.
4926
4927C-c [ reftex-citation
4928 Prompts for a regular expression and displays a list of matching BibTeX
4929 database entries. The selected entry is cited with a \cite{KEY} macro.
4930
4931C-c & reftex-view-crossref
4932 Views the cross reference of a \ref or \cite command near point.
4933
4934C-c = reftex-toc
4935 Shows a table of contents of the (multifile) document. From there you
4936 can quickly jump to every section.
4937
4938Under X, RefTeX installs a "Ref" menu in the menu bar, with additional
4939commands. Press `?' to get help when a prompt mentions this feature.
4940Full documentation and customization examples are in the file
4941reftex.el. You can use the finder to view the file documentation:
4942C-h p --> tex --> reftex.el
4943
4944** Changes in BibTeX mode.
4945
4946*** Info documentation is now available.
4947
4948*** Don't allow parentheses in string constants anymore. This confused
4949both the BibTeX program and Emacs BibTeX mode.
4950
4951*** Renamed variable bibtex-mode-user-optional-fields to
4952bibtex-user-optional-fields.
4953
4954*** Removed variable bibtex-include-OPTannote
4955(use bibtex-user-optional-fields instead).
4956
4957*** New interactive functions to copy and kill fields and complete
4958entries to the BibTeX kill ring, from where they can be yanked back by
4959appropriate functions.
4960
4961*** New interactive functions for repositioning and marking of
4962entries. They are bound by default to M-C-l and M-C-h.
4963
4964*** New hook bibtex-clean-entry-hook. It is called after entry has
4965been cleaned.
4966
4967*** New variable bibtex-field-delimiters, which replaces variables
4968bibtex-field-{left|right}-delimiter.
4969
4970*** New variable bibtex-entry-delimiters to determine how entries
4971shall be delimited.
4972
4973*** Allow preinitialization of fields. See documentation of
4974bibtex-user-optional-fields, bibtex-entry-field-alist, and
4975bibtex-include-OPTkey for details.
4976
4977*** Book and InBook entries require either an author or an editor
4978field. This is now supported by bibtex.el. Alternative fields are
4979prefixed with `ALT'.
4980
4981*** New variable bibtex-entry-format, which replaces variable
4982bibtex-clean-entry-zap-empty-opts and allows specification of many
4983formatting options performed on cleaning an entry (see variable
4984documentation).
4985
4986*** Even more control on how automatic keys are generated. See
4987documentation of bibtex-generate-autokey for details. Transcriptions
4988for foreign languages other than German are now handled, too.
4989
4990*** New boolean user option bibtex-comma-after-last-field to decide if
4991comma should be inserted at end of last field.
4992
4993*** New boolean user option bibtex-align-at-equal-sign to determine if
4994alignment should be made at left side of field contents or at equal
4995signs. New user options to control entry layout (e.g. indentation).
4996
4997*** New function bibtex-fill-entry to realign entries.
4998
4999*** New function bibtex-reformat to reformat region or buffer.
5000
5001*** New function bibtex-convert-alien to convert a BibTeX database
5002from alien sources.
5003
5004*** New function bibtex-complete-key (similar to bibtex-complete-string)
5005to complete prefix to a key defined in buffer. Mainly useful in
5006crossref entries.
5007
5008*** New function bibtex-count-entries to count entries in buffer or
5009region.
5010
5011*** Added support for imenu.
5012
5013*** The function `bibtex-validate' now checks current region instead
5014of buffer if mark is active. Now it shows all errors of buffer in a
5015`compilation mode' buffer. You can use the normal commands (e.g.
5016`next-error') for compilation modes to jump to errors.
5017
5018*** New variable `bibtex-string-file-path' to determine where the files
5019from `bibtex-string-files' are searched.
5020
5021** Iso Accents mode now supports Latin-3 as an alternative.
5022
5023** The function using-unix-filesystems has been replaced by the
5024functions add-untranslated-filesystem and remove-untranslated-filesystem.
5025Each of these functions takes the name of a drive letter or directory
5026as an argument.
5027
5028When a filesystem is added as untranslated, all files on it are read
5029and written in binary mode (no cr/lf translation is performed).
5030
5031** browse-url changes
5032
5033*** New methods for: Grail (browse-url-generic), MMM (browse-url-mmm),
5034Lynx in a separate xterm (browse-url-lynx-xterm) or in an Emacs window
5035(browse-url-lynx-emacs), remote W3 (browse-url-w3-gnudoit), generic
5036non-remote-controlled browsers (browse-url-generic) and associated
5037customization variables.
5038
5039*** New commands `browse-url-of-region' and `browse-url'.
5040
5041*** URLs marked up with <URL:...> (RFC1738) work if broken across
5042lines. Browsing methods can be associated with URL regexps
5043(e.g. mailto: URLs) via `browse-url-browser-function'.
5044
5045** Changes in Ediff
5046
5047*** Clicking Mouse-2 on a brief command description in Ediff control panel
5048pops up the Info file for this command.
5049
5050*** There is now a variable, ediff-autostore-merges, which controls whether
5051the result of a merge is saved in a file. By default, this is done only when
5052merge is done from a session group (eg, when merging files in two different
5053directories).
5054
5055*** Since Emacs 19.31 (this hasn't been announced before), Ediff can compare
5056and merge groups of files residing in different directories, or revisions of
5057files in the same directory.
5058
5059*** Since Emacs 19.31, Ediff can apply multi-file patches interactively.
5060The patches must be in the context format or GNU unified format. (The bug
5061related to the GNU format has now been fixed.)
5062
5063** Changes in Viper
5064
5065*** The startup file is now .viper instead of .vip
5066*** All variable/function names have been changed to start with viper-
5067 instead of vip-.
5068*** C-\ now simulates the meta-key in all Viper states.
5069*** C-z in Insert state now escapes to Vi for the duration of the next
5070Viper command. In Vi and Insert states, C-z behaves as before.
5071*** C-c \ escapes to Vi for one command if Viper is in Insert or Emacs states.
5072*** _ is no longer the meta-key in Vi state.
5073*** The variable viper-insert-state-cursor-color can be used to change cursor
5074color when Viper is in insert state.
5075*** If search lands the cursor near the top or the bottom of the window,
5076Viper pulls the window up or down to expose more context. The variable
5077viper-adjust-window-after-search controls this behavior.
5078
5079** Etags changes.
5080
5081*** In C, C++, Objective C and Java, Etags tags global variables by
5082default. The resulting tags files are inflated by 30% on average.
5083Use --no-globals to turn this feature off. Etags can also tag
5084variables which are members of structure-like constructs, but it does
5085not by default. Use --members to turn this feature on.
5086
5087*** C++ member functions are now recognized as tags.
5088
5089*** Java is tagged like C++. In addition, "extends" and "implements"
5090constructs are tagged. Files are recognised by the extension .java.
5091
5092*** Etags can now handle programs written in Postscript. Files are
5093recognised by the extensions .ps and .pdb (Postscript with C syntax).
5094In Postscript, tags are lines that start with a slash.
5095
5096*** Etags now handles Objective C and Objective C++ code. The usual C and
5097C++ tags are recognized in these languages; in addition, etags
5098recognizes special Objective C syntax for classes, class categories,
5099methods and protocols.
5100
5101*** Etags also handles Cobol. Files are recognised by the extension
5102.cobol. The tagged lines are those containing a word that begins in
5103column 8 and ends in a full stop, i.e. anything that could be a
5104paragraph name.
5105
5106*** Regexps in Etags now support intervals, as in ed or grep. The syntax of
5107an interval is \{M,N\}, and it means to match the preceding expression
5108at least M times and as many as N times.
5109
5110** The format for specifying a custom format for time-stamp to insert
5111in files has changed slightly.
5112
5113With the new enhancements to the functionality of format-time-string,
5114time-stamp-format will change to be eventually compatible with it.
5115This conversion is being done in two steps to maintain compatibility
5116with old time-stamp-format values.
5117
5118In the new scheme, alternate case is signified by the number-sign
5119(`#') modifier, rather than changing the case of the format character.
5120This feature is as yet incompletely implemented for compatibility
5121reasons.
5122
5123In the old time-stamp-format, all numeric fields defaulted to their
5124natural width. (With format-time-string, each format has a
5125fixed-width default.) In this version, you can specify the colon
5126(`:') modifier to a numeric conversion to mean "give me the historical
5127time-stamp-format width default." Do not use colon if you are
5128specifying an explicit width, as in "%02d".
5129
5130Numbers are no longer truncated to the requested width, except in the
5131case of "%02y", which continues to give a two-digit year. Digit
5132truncation probably wasn't being used for anything else anyway.
5133
5134The new formats will work with old versions of Emacs. New formats are
5135being recommended now to allow time-stamp-format to change in the
5136future to be compatible with format-time-string. The new forms being
5137recommended now will continue to work then.
5138
5139See the documentation string for the variable time-stamp-format for
5140details.
5141
5142** There are some additional major modes:
5143
5144dcl-mode, for editing VMS DCL files.
5145m4-mode, for editing files of m4 input.
5146meta-mode, for editing MetaFont and MetaPost source files.
5147
5148** In Shell mode, the command shell-copy-environment-variable lets you
5149copy the value of a specified environment variable from the subshell
5150into Emacs.
5151
5152** New Lisp packages include:
5153
5154*** battery.el displays battery status for laptops.
5155
5156*** M-x bruce (named after Lenny Bruce) is a program that might
5157be used for adding some indecent words to your email.
5158
5159*** M-x crisp-mode enables an emulation for the CRiSP editor.
5160
5161*** M-x dirtrack arranges for better tracking of directory changes
5162in shell buffers.
5163
5164*** The new library elint.el provides for linting of Emacs Lisp code.
5165See the documentation for `elint-initialize', `elint-current-buffer'
5166and `elint-defun'.
5167
5168*** M-x expand-add-abbrevs defines a special kind of abbrev which is
5169meant for programming constructs. These abbrevs expand like ordinary
5170ones, when you type SPC, but only at the end of a line and not within
5171strings or comments.
5172
5173These abbrevs can act as templates: you can define places within an
5174abbrev for insertion of additional text. Once you expand the abbrev,
5175you can then use C-x a p and C-x a n to move back and forth to these
5176insertion points. Thus you can conveniently insert additional text
5177at these points.
5178
5179*** filecache.el remembers the location of files so that you
5180can visit them by short forms of their names.
5181
5182*** find-func.el lets you find the definition of the user-loaded
5183Emacs Lisp function at point.
5184
5185*** M-x handwrite converts text to a "handwritten" picture.
5186
5187*** M-x iswitchb-buffer is a command for switching to a buffer, much like
5188switch-buffer, but it reads the argument in a more helpful way.
5189
5190*** M-x landmark implements a neural network for landmark learning.
5191
5192*** M-x locate provides a convenient interface to the `locate' program.
5193
5194*** M4 mode is a new mode for editing files of m4 input.
5195
5196*** mantemp.el creates C++ manual template instantiations
5197from the GCC error messages which indicate which instantiations are needed.
5198
5199*** mouse-copy.el provides a one-click copy and move feature.
5200You can drag a region with M-mouse-1, and it is automatically
5201inserted at point. M-Shift-mouse-1 deletes the text from its
5202original place after inserting the copy.
5203
5204*** mouse-drag.el lets you do scrolling by dragging Mouse-2
5205on the buffer.
5206
5207You click the mouse and move; that distance either translates into the
5208velocity to scroll (with mouse-drag-throw) or the distance to scroll
5209(with mouse-drag-drag). Horizontal scrolling is enabled when needed.
5210
5211Enable mouse-drag with:
5212 (global-set-key [down-mouse-2] 'mouse-drag-throw)
5213-or-
5214 (global-set-key [down-mouse-2] 'mouse-drag-drag)
5215
5216*** mspools.el is useful for determining which mail folders have
5217mail waiting to be read in them. It works with procmail.
5218
5219*** Octave mode is a major mode for editing files of input for Octave.
5220It comes with a facility for communicating with an Octave subprocess.
5221
5222*** ogonek
5223
5224The ogonek package provides functions for changing the coding of
5225Polish diacritic characters in buffers. Codings known from various
5226platforms are supported such as ISO8859-2, Mazovia, IBM Latin2, and
5227TeX. For example, you can change the coding from Mazovia to
5228ISO8859-2. Another example is a change of coding from ISO8859-2 to
5229prefix notation (in which `/a' stands for the aogonek character, for
5230instance) and vice versa.
5231
5232To use this package load it using
5233 M-x load-library [enter] ogonek
5234Then, you may get an explanation by calling one of
5235 M-x ogonek-jak -- in Polish
5236 M-x ogonek-how -- in English
5237The info specifies the commands and variables provided as well as the
5238ways of customization in `.emacs'.
5239
5240*** Interface to ph.
5241
5242Emacs provides a client interface to CCSO Nameservers (ph/qi)
5243
5244The CCSO nameserver is used in many universities to provide directory
5245services about people. ph.el provides a convenient Emacs interface to
5246these servers.
5247
5248*** uce.el is useful for replying to unsolicited commercial email.
5249
5250*** vcursor.el implements a "virtual cursor" feature.
5251You can move the virtual cursor with special commands
5252while the real cursor does not move.
5253
5254*** webjump.el is a "hot list" package which you can set up
5255for visiting your favorite web sites.
5256
5257*** M-x winner-mode is a minor mode which saves window configurations,
5258so you can move back to other configurations that you have recently used.
5259
5260** movemail change
5261
5262Movemail no longer needs to be installed setuid root in order for POP
5263mail retrieval to function properly. This is because it no longer
5264supports the RPOP (reserved-port POP) protocol; instead, it uses the
5265user's POP password to authenticate to the mail server.
5266
5267This change was made earlier, but not reported in NEWS before.
5268\f
5269* Emacs 20.1 changes for MS-DOS and MS-Windows.
5270
5271** Changes in handling MS-DOS/MS-Windows text files.
5272
5273Emacs handles three different conventions for representing
5274end-of-line: CRLF for MSDOS, LF for Unix and GNU, and CR (used on the
5275Macintosh). Emacs determines which convention is used in a specific
5276file based on the contents of that file (except for certain special
5277file names), and when it saves the file, it uses the same convention.
5278
5279To save the file and change the end-of-line convention, you can use
5280C-x RET f (set-buffer-file-coding-system) to specify a different
5281coding system for the buffer. Then, when you save the file, the newly
5282specified coding system will take effect. For example, to save with
5283LF, specify undecided-unix (or some other ...-unix coding system); to
5284save with CRLF, specify undecided-dos.
5285\f
5286* Lisp Changes in Emacs 20.1
5287
5288** Byte-compiled files made with Emacs 20 will, in general, work in
5289Emacs 19 as well, as long as the source code runs in Emacs 19. And
5290vice versa: byte-compiled files made with Emacs 19 should also run in
5291Emacs 20, as long as the program itself works in Emacs 20.
5292
5293** Windows-specific functions and variables have been renamed
5294to start with w32- instead of win32-.
5295
5296In hacker language, calling something a "win" is a form of praise. We
5297don't want to praise a non-free Microsoft system, so we don't call it
5298"win".
5299
5300** Basic Lisp changes
5301
5302*** A symbol whose name starts with a colon now automatically
5303evaluates to itself. Therefore such a symbol can be used as a constant.
5304
5305*** The defined purpose of `defconst' has been changed. It should now
5306be used only for values that should not be changed whether by a program
5307or by the user.
5308
5309The actual behavior of defconst has not been changed.
5310
5311*** There are new macros `when' and `unless'
5312
5313(when CONDITION BODY...) is short for (if CONDITION (progn BODY...))
5314(unless CONDITION BODY...) is short for (if CONDITION nil BODY...)
5315
5316*** Emacs now defines functions caar, cadr, cdar and cddr with their
5317usual Lisp meanings. For example, caar returns the car of the car of
5318its argument.
5319
5320*** equal, when comparing strings, now ignores their text properties.
5321
5322*** The new function `functionp' tests whether an object is a function.
5323
5324*** arrayp now returns t for char-tables and bool-vectors.
5325
5326*** Certain primitives which use characters (as integers) now get an
5327error if the integer is not a valid character code. These primitives
5328include insert-char, char-to-string, and the %c construct in the
5329`format' function.
5330
5331*** The `require' function now insists on adding a suffix, either .el
5332or .elc, to the file name. Thus, (require 'foo) will not use a file
5333whose name is just foo. It insists on foo.el or foo.elc.
5334
5335*** The `autoload' function, when the file name does not contain
5336either a directory name or the suffix .el or .elc, insists on
5337adding one of these suffixes.
5338
5339*** string-to-number now takes an optional second argument BASE
5340which specifies the base to use when converting an integer.
5341If BASE is omitted, base 10 is used.
5342
5343We have not implemented other radices for floating point numbers,
5344because that would be much more work and does not seem useful.
5345
5346*** substring now handles vectors as well as strings.
5347
5348*** The Common Lisp function eql is no longer defined normally.
5349You must load the `cl' library to define it.
5350
5351*** The new macro `with-current-buffer' lets you evaluate an expression
5352conveniently with a different current buffer. It looks like this:
5353
5354 (with-current-buffer BUFFER BODY-FORMS...)
5355
5356BUFFER is the expression that says which buffer to use.
5357BODY-FORMS say what to do in that buffer.
5358
5359*** The new primitive `save-current-buffer' saves and restores the
5360choice of current buffer, like `save-excursion', but without saving or
5361restoring the value of point or the mark. `with-current-buffer'
5362works using `save-current-buffer'.
5363
5364*** The new macro `with-temp-file' lets you do some work in a new buffer and
5365write the output to a specified file. Like `progn', it returns the value
5366of the last form.
5367
5368*** The new macro `with-temp-buffer' lets you do some work in a new buffer,
5369which is discarded after use. Like `progn', it returns the value of the
5370last form. If you wish to return the buffer contents, use (buffer-string)
5371as the last form.
5372
5373*** The new function split-string takes a string, splits it at certain
5374characters, and returns a list of the substrings in between the
5375matches.
5376
5377For example, (split-string "foo bar lose" " +") returns ("foo" "bar" "lose").
5378
5379*** The new macro with-output-to-string executes some Lisp expressions
5380with standard-output set up so that all output feeds into a string.
5381Then it returns that string.
5382
5383For example, if the current buffer name is `foo',
5384
5385(with-output-to-string
5386 (princ "The buffer is ")
5387 (princ (buffer-name)))
5388
5389returns "The buffer is foo".
5390
5391** Non-ASCII characters are now supported, if enable-multibyte-characters
5392is non-nil.
5393
5394These characters have character codes above 256. When inserted in the
5395buffer or stored in a string, they are represented as multibyte
5396characters that occupy several buffer positions each.
5397
5398*** When enable-multibyte-characters is non-nil, a single character in
5399a buffer or string can be two or more bytes (as many as four).
5400
5401Buffers and strings are still made up of unibyte elements;
5402character positions and string indices are always measured in bytes.
5403Therefore, moving forward one character can increase the buffer
5404position by 2, 3 or 4. The function forward-char moves by whole
5405characters, and therefore is no longer equivalent to
5406 (lambda (n) (goto-char (+ (point) n))).
5407
5408ASCII characters (codes 0 through 127) are still single bytes, always.
5409Sequences of byte values 128 through 255 are used to represent
5410non-ASCII characters. These sequences are called "multibyte
5411characters".
5412
5413The first byte of a multibyte character is always in the range 128
5414through 159 (octal 0200 through 0237). These values are called
5415"leading codes". The second and subsequent bytes are always in the
5416range 160 through 255 (octal 0240 through 0377). The first byte, the
5417leading code, determines how many bytes long the sequence is.
5418
5419*** The function forward-char moves over characters, and therefore
5420(forward-char 1) may increase point by more than 1 if it moves over a
5421multibyte character. Likewise, delete-char always deletes a
5422character, which may be more than one buffer position.
5423
5424This means that some Lisp programs, which assume that a character is
5425always one buffer position, need to be changed.
5426
5427However, all ASCII characters are always one buffer position.
5428
5429*** The regexp [\200-\377] no longer matches all non-ASCII characters,
5430because when enable-multibyte-characters is non-nil, these characters
5431have codes that are not in the range octal 200 to octal 377. However,
5432the regexp [^\000-\177] does match all non-ASCII characters,
5433guaranteed.
5434
5435*** The function char-boundary-p returns non-nil if position POS is
5436between two characters in the buffer (not in the middle of a
5437character).
5438
5439When the value is non-nil, it says what kind of character follows POS:
5440
5441 0 if POS is at an ASCII character or at the end of range,
5442 1 if POS is before a 2-byte length multi-byte form,
5443 2 if POS is at a head of 3-byte length multi-byte form,
5444 3 if POS is at a head of 4-byte length multi-byte form,
5445 4 if POS is at a head of multi-byte form of a composite character.
5446
5447*** The function char-bytes returns how many bytes the character CHAR uses.
5448
5449*** Strings can contain multibyte characters. The function
5450`length' returns the string length counting bytes, which may be
5451more than the number of characters.
5452
5453You can include a multibyte character in a string constant by writing
5454it literally. You can also represent it with a hex escape,
5455\xNNNNNNN..., using as many digits as necessary. Any character which
5456is not a valid hex digit terminates this construct. If you want to
5457follow it with a character that is a hex digit, write backslash and
5458newline in between; that will terminate the hex escape.
5459
5460*** The function concat-chars takes arguments which are characters
5461and returns a string containing those characters.
5462
5463*** The function sref access a multibyte character in a string.
5464(sref STRING INDX) returns the character in STRING at INDEX. INDEX
5465counts from zero. If INDEX is at a position in the middle of a
5466character, sref signals an error.
5467
5468*** The function chars-in-string returns the number of characters
5469in a string. This is less than the length of the string, if the
5470string contains multibyte characters (the length counts bytes).
5471
5472*** The function chars-in-region returns the number of characters
5473in a region from BEG to END. This is less than (- END BEG) if the
5474region contains multibyte characters (the length counts bytes).
5475
5476*** The function string-to-list converts a string to a list of
5477the characters in it. string-to-vector converts a string
5478to a vector of the characters in it.
5479
5480*** The function store-substring alters part of the contents
5481of a string. You call it as follows:
5482
5483 (store-substring STRING IDX OBJ)
5484
5485This says to alter STRING, by storing OBJ starting at index IDX in
5486STRING. OBJ may be either a character or a (smaller) string.
5487This function really does alter the contents of STRING.
5488Since it is impossible to change the length of an existing string,
5489it is an error if OBJ doesn't fit within STRING's actual length.
5490
5491*** char-width returns the width (in columns) of the character CHAR,
5492if it were displayed in the current buffer and the selected window.
5493
5494*** string-width returns the width (in columns) of the text in STRING,
5495if it were displayed in the current buffer and the selected window.
5496
5497*** truncate-string-to-width shortens a string, if necessary,
5498to fit within a certain number of columns. (Of course, it does
5499not alter the string that you give it; it returns a new string
5500which contains all or just part of the existing string.)
5501
5502(truncate-string-to-width STR END-COLUMN &optional START-COLUMN PADDING)
5503
5504This returns the part of STR up to column END-COLUMN.
5505
5506The optional argument START-COLUMN specifies the starting column.
5507If this is non-nil, then the first START-COLUMN columns of the string
5508are not included in the resulting value.
5509
5510The optional argument PADDING, if non-nil, is a padding character to be added
5511at the beginning and end the resulting string, to extend it to exactly
5512WIDTH columns. If PADDING is nil, that means do not pad; then, if STRING
5513is narrower than WIDTH, the value is equal to STRING.
5514
5515If PADDING and START-COLUMN are both non-nil, and if there is no clean
5516place in STRING that corresponds to START-COLUMN (because one
5517character extends across that column), then the padding character
5518PADDING is added one or more times at the beginning of the result
5519string, so that its columns line up as if it really did start at
5520column START-COLUMN.
5521
5522*** When the functions in the list after-change-functions are called,
5523the third argument is the number of bytes in the pre-change text, not
5524necessarily the number of characters. It is, in effect, the
5525difference in buffer position between the beginning and the end of the
5526changed text, before the change.
5527
5528*** The characters Emacs uses are classified in various character
5529sets, each of which has a name which is a symbol. In general there is
5530one character set for each script, not for each language.
5531
5532**** The function charsetp tests whether an object is a character set name.
5533
5534**** The variable charset-list holds a list of character set names.
5535
5536**** char-charset, given a character code, returns the name of the character
5537set that the character belongs to. (The value is a symbol.)
5538
5539**** split-char, given a character code, returns a list containing the
5540name of the character set, followed by one or two byte-values
5541which identify the character within that character set.
5542
5543**** make-char, given a character set name and one or two subsequent
5544byte-values, constructs a character code. This is roughly the
5545opposite of split-char.
5546
5547**** find-charset-region returns a list of the character sets
5548of all the characters between BEG and END.
5549
5550**** find-charset-string returns a list of the character sets
5551of all the characters in a string.
5552
5553*** Here are the Lisp facilities for working with coding systems
5554and specifying coding systems.
5555
5556**** The function coding-system-list returns a list of all coding
5557system names (symbols). With optional argument t, it returns a list
5558of all distinct base coding systems, not including variants.
5559(Variant coding systems are those like latin-1-dos, latin-1-unix
5560and latin-1-mac which specify the end-of-line conversion as well
5561as what to do about code conversion.)
5562
5563**** coding-system-p tests a symbol to see if it is a coding system
5564name. It returns t if so, nil if not.
5565
5566**** file-coding-system-alist specifies which coding systems to use
5567for certain file names. It works like network-coding-system-alist,
5568except that the PATTERN is matched against the file name.
5569
5570Each element has the format (PATTERN . VAL), where PATTERN determines
5571which file names the element applies to. PATTERN should be a regexp
5572to match against a file name.
5573
5574VAL is a coding system, a cons cell containing two coding systems, or
5575a function symbol. If VAL is a coding system, it is used for both
5576decoding what received from the network stream and encoding what sent
5577to the network stream. If VAL is a cons cell containing two coding
5578systems, the car specifies the coding system for decoding, and the cdr
5579specifies the coding system for encoding.
5580
5581If VAL is a function symbol, the function must return a coding system
5582or a cons cell containing two coding systems, which is used as above.
5583
5584**** The variable network-coding-system-alist specifies
5585the coding system to use for network sockets.
5586
5587Each element has the format (PATTERN . VAL), where PATTERN determines
5588which network sockets the element applies to. PATTERN should be
5589either a port number or a regular expression matching some network
5590service names.
5591
5592VAL is a coding system, a cons cell containing two coding systems, or
5593a function symbol. If VAL is a coding system, it is used for both
5594decoding what received from the network stream and encoding what sent
5595to the network stream. If VAL is a cons cell containing two coding
5596systems, the car specifies the coding system for decoding, and the cdr
5597specifies the coding system for encoding.
5598
5599If VAL is a function symbol, the function must return a coding system
5600or a cons cell containing two coding systems, which is used as above.
5601
5602**** process-coding-system-alist specifies which coding systems to use
5603for certain subprocess. It works like network-coding-system-alist,
5604except that the PATTERN is matched against the program name used to
5605start the subprocess.
5606
5607**** The variable default-process-coding-system specifies the coding
5608systems to use for subprocess (and net connection) input and output,
5609when nothing else specifies what to do. The value is a cons cell
5610(OUTPUT-CODING . INPUT-CODING). OUTPUT-CODING applies to output
5611to the subprocess, and INPUT-CODING applies to input from it.
5612
5613**** The variable coding-system-for-write, if non-nil, specifies the
5614coding system to use for writing a file, or for output to a synchronous
5615subprocess.
5616
5617It also applies to any asynchronous subprocess or network connection,
5618but in a different way: the value of coding-system-for-write when you
5619start the subprocess or connection affects that subprocess or
5620connection permanently or until overridden.
5621
5622The variable coding-system-for-write takes precedence over
5623file-coding-system-alist, process-coding-system-alist and
5624network-coding-system-alist, and all other methods of specifying a
5625coding system for output. But most of the time this variable is nil.
5626It exists so that Lisp programs can bind it to a specific coding
5627system for one operation at a time.
5628
5629**** coding-system-for-read applies similarly to input from
5630files, subprocesses or network connections.
5631
5632**** The function process-coding-system tells you what
5633coding systems(s) an existing subprocess is using.
5634The value is a cons cell,
5635 (DECODING-CODING-SYSTEM . ENCODING-CODING-SYSTEM)
5636where DECODING-CODING-SYSTEM is used for decoding output from
5637the subprocess, and ENCODING-CODING-SYSTEM is used for encoding
5638input to the subprocess.
5639
5640**** The function set-process-coding-system can be used to
5641change the coding systems in use for an existing subprocess.
5642
5643** Emacs has a new facility to help users manage the many
5644customization options. To make a Lisp program work with this facility,
5645you need to use the new macros defgroup and defcustom.
5646
5647You use defcustom instead of defvar, for defining a user option
5648variable. The difference is that you specify two additional pieces of
5649information (usually): the "type" which says what values are
5650legitimate, and the "group" which specifies the hierarchy for
5651customization.
5652
5653Thus, instead of writing
5654
5655 (defvar foo-blurgoze nil
5656 "*Non-nil means that foo will act very blurgozely.")
5657
5658you would now write this:
5659
5660 (defcustom foo-blurgoze nil
5661 "*Non-nil means that foo will act very blurgozely."
5662 :type 'boolean
5663 :group foo)
5664
5665The type `boolean' means that this variable has only
5666two meaningful states: nil and non-nil. Other type values
5667describe other possibilities; see the manual for Custom
5668for a description of them.
5669
5670The "group" argument is used to specify a group which the option
5671should belong to. You define a new group like this:
5672
5673 (defgroup ispell nil
5674 "Spell checking using Ispell."
5675 :group 'processes)
5676
5677The "group" argument in defgroup specifies the parent group. The root
5678group is called `emacs'; it should not contain any variables itself,
5679but only other groups. The immediate subgroups of `emacs' correspond
5680to the keywords used by C-h p. Under these subgroups come
5681second-level subgroups that belong to individual packages.
5682
5683Each Emacs package should have its own set of groups. A simple
5684package should have just one group; a more complex package should
5685have a hierarchy of its own groups. The sole or root group of a
5686package should be a subgroup of one or more of the "keyword"
5687first-level subgroups.
5688
5689** New `widget' library for inserting UI components in buffers.
5690
5691This library, used by the new custom library, is documented in a
5692separate manual that accompanies Emacs.
5693
5694** easy-mmode
5695
5696The easy-mmode package provides macros and functions that make
5697developing minor modes easier. Roughly, the programmer has to code
5698only the functionality of the minor mode. All the rest--toggles,
5699predicate, and documentation--can be done in one call to the macro
5700`easy-mmode-define-minor-mode' (see the documentation). See also
5701`easy-mmode-define-keymap'.
5702
5703** Text property changes
5704
5705*** The `intangible' property now works on overlays as well as on a
5706text property.
5707
5708*** The new functions next-char-property-change and
5709previous-char-property-change scan through the buffer looking for a
5710place where either a text property or an overlay might change. The
5711functions take two arguments, POSITION and LIMIT. POSITION is the
5712starting position for the scan. LIMIT says where to stop the scan.
5713
5714If no property change is found before LIMIT, the value is LIMIT. If
5715LIMIT is nil, scan goes to the beginning or end of the accessible part
5716of the buffer. If no property change is found, the value is the
5717position of the beginning or end of the buffer.
5718
5719*** In the `local-map' text property or overlay property, the property
5720value can now be a symbol whose function definition is a keymap. This
5721is an alternative to using the keymap itself.
5722
5723** Changes in invisibility features
5724
5725*** Isearch can now temporarily show parts of the buffer which are
5726hidden by an overlay with a invisible property, when the search match
5727is inside that portion of the buffer. To enable this the overlay
5728should have a isearch-open-invisible property which is a function that
5729would be called having the overlay as an argument, the function should
5730make the overlay visible.
5731
5732During incremental search the overlays are shown by modifying the
5733invisible and intangible properties, if beside this more actions are
5734needed the overlay should have a isearch-open-invisible-temporary
5735which is a function. The function is called with 2 arguments: one is
5736the overlay and the second is nil when it should show the overlay and
5737t when it should hide it.
5738
5739*** add-to-invisibility-spec, remove-from-invisibility-spec
5740
5741Modes that use overlays to hide portions of a buffer should set the
5742invisible property of the overlay to the mode's name (or another symbol)
5743and modify the `buffer-invisibility-spec' to include that symbol.
5744Use `add-to-invisibility-spec' and `remove-from-invisibility-spec' to
5745manipulate the `buffer-invisibility-spec'.
5746Here is an example of how to do this:
5747
5748 ;; If we want to display an ellipsis:
5749 (add-to-invisibility-spec '(my-symbol . t))
5750 ;; If you don't want ellipsis:
5751 (add-to-invisibility-spec 'my-symbol)
5752
5753 ...
5754 (overlay-put (make-overlay beginning end) 'invisible 'my-symbol)
5755
5756 ...
5757 ;; When done with the overlays:
5758 (remove-from-invisibility-spec '(my-symbol . t))
5759 ;; Or respectively:
5760 (remove-from-invisibility-spec 'my-symbol)
5761
5762** Changes in syntax parsing.
5763
5764*** The syntax-directed buffer-scan functions (such as
5765`parse-partial-sexp', `forward-word' and similar functions) can now
5766obey syntax information specified by text properties, if the variable
5767`parse-sexp-lookup-properties' is non-nil.
5768
5769If the value of `parse-sexp-lookup-properties' is nil, the behavior
5770is as before: the syntax-table of the current buffer is always
5771used to determine the syntax of the character at the position.
5772
5773When `parse-sexp-lookup-properties' is non-nil, the syntax of a
5774character in the buffer is calculated thus:
5775
5776 a) if the `syntax-table' text-property of that character
5777 is a cons, this cons becomes the syntax-type;
5778
5779 Valid values of `syntax-table' text-property are: nil, a valid
5780 syntax-table, and a valid syntax-table element, i.e.,
5781 a cons cell of the form (SYNTAX-CODE . MATCHING-CHAR).
5782
5783 b) if the character's `syntax-table' text-property
5784 is a syntax table, this syntax table is used
5785 (instead of the syntax-table of the current buffer) to
5786 determine the syntax type of the character.
5787
5788 c) otherwise the syntax-type is determined by the syntax-table
5789 of the current buffer.
5790
5791*** The meaning of \s in regular expressions is also affected by the
5792value of `parse-sexp-lookup-properties'. The details are the same as
5793for the syntax-directed buffer-scan functions.
5794
5795*** There are two new syntax-codes, `!' and `|' (numeric values 14
5796and 15). A character with a code `!' starts a comment which is ended
5797only by another character with the same code (unless quoted). A
5798character with a code `|' starts a string which is ended only by
5799another character with the same code (unless quoted).
5800
5801These codes are mainly meant for use as values of the `syntax-table'
5802text property.
5803
5804*** The function `parse-partial-sexp' has new semantics for the sixth
5805arg COMMENTSTOP. If it is `syntax-table', parse stops after the start
5806of a comment or a string, or after end of a comment or a string.
5807
5808*** The state-list which the return value from `parse-partial-sexp'
5809(and can also be used as an argument) now has an optional ninth
5810element: the character address of the start of last comment or string;
5811nil if none. The fourth and eighth elements have special values if the
5812string/comment is started by a "!" or "|" syntax-code.
5813
5814*** Since new features of `parse-partial-sexp' allow a complete
5815syntactic parsing, `font-lock' no longer supports
5816`font-lock-comment-start-regexp'.
5817
5818** Changes in face features
5819
5820*** The face functions are now unconditionally defined in Emacs, even
5821if it does not support displaying on a device that supports faces.
5822
5823*** The function face-documentation returns the documentation string
5824of a face (or nil if it doesn't have one).
5825
5826*** The function face-bold-p returns t if a face should be bold.
5827set-face-bold-p sets that flag.
5828
5829*** The function face-italic-p returns t if a face should be italic.
5830set-face-italic-p sets that flag.
5831
5832*** You can now specify foreground and background colors for text
5833by adding elements of the form (foreground-color . COLOR-NAME)
5834and (background-color . COLOR-NAME) to the list of faces in
5835the `face' property (either the character's text property or an
5836overlay property).
5837
5838This means that you no longer need to create named faces to use
5839arbitrary colors in a Lisp package.
5840
5841** Changes in file-handling functions
5842
5843*** File-access primitive functions no longer discard an extra redundant
5844directory name from the beginning of the file name. In other words,
5845they no longer do anything special with // or /~. That conversion
5846is now done only in substitute-in-file-name.
5847
5848This makes it possible for a Lisp program to open a file whose name
5849begins with ~.
5850
5851*** If copy-file is unable to set the date of the output file,
5852it now signals an error with the condition file-date-error.
5853
5854*** The inode number returned by file-attributes may be an integer (if
5855the number fits in a Lisp integer) or a list of integers.
5856
5857*** insert-file-contents can now read from a special file,
5858as long as the arguments VISIT and REPLACE are nil.
5859
5860*** The RAWFILE arg to find-file-noselect, if non-nil, now suppresses
5861character code conversion as well as other things.
5862
5863Meanwhile, this feature does work with remote file names
5864(formerly it did not).
5865
5866*** Lisp packages which create temporary files should use the TMPDIR
5867environment variable to decide which directory to put them in.
5868
5869*** interpreter-mode-alist elements now specify regexps
5870instead of constant strings.
5871
5872*** expand-file-name no longer treats `//' or `/~' specially. It used
5873to delete all the text of a file name up through the first slash of
5874any `//' or `/~' sequence. Now it passes them straight through.
5875
5876substitute-in-file-name continues to treat those sequences specially,
5877in the same way as before.
5878
5879*** The variable `format-alist' is more general now.
5880The FROM-FN and TO-FN in a format definition can now be strings
5881which specify shell commands to use as filters to perform conversion.
5882
5883*** The new function access-file tries to open a file, and signals an
5884error if that fails. If the open succeeds, access-file does nothing
5885else, and returns nil.
5886
5887*** The function insert-directory now signals an error if the specified
5888directory cannot be listed.
5889
5890** Changes in minibuffer input
5891
5892*** The functions read-buffer, read-variable, read-command, read-string
5893read-file-name, read-from-minibuffer and completing-read now take an
5894additional argument which specifies the default value. If this
5895argument is non-nil, it should be a string; that string is used in two
5896ways:
5897
5898 It is returned if the user enters empty input.
5899 It is available through the history command M-n.
5900
5901*** The functions read-string, read-from-minibuffer,
5902read-no-blanks-input and completing-read now take an additional
5903argument INHERIT-INPUT-METHOD. If this is non-nil, then the
5904minibuffer inherits the current input method and the setting of
5905enable-multibyte-characters from the previously current buffer.
5906
5907In an interactive spec, you can use M instead of s to read an
5908argument in this way.
5909
5910*** All minibuffer input functions discard text properties
5911from the text you enter in the minibuffer, unless the variable
5912minibuffer-allow-text-properties is non-nil.
5913
5914** Echo area features
5915
5916*** Clearing the echo area now runs the normal hook
5917echo-area-clear-hook. Note that the echo area can be used while the
5918minibuffer is active; in that case, the minibuffer is still active
5919after the echo area is cleared.
5920
5921*** The function current-message returns the message currently displayed
5922in the echo area, or nil if there is none.
5923
5924** Keyboard input features
5925
5926*** tty-erase-char is a new variable that reports which character was
5927set up as the terminal's erase character when time Emacs was started.
5928
5929*** num-nonmacro-input-events is the total number of input events
5930received so far from the terminal. It does not count those generated
5931by keyboard macros.
5932
5933** Frame-related changes
5934
5935*** make-frame runs the normal hook before-make-frame-hook just before
5936creating a frame, and just after creating a frame it runs the abnormal
5937hook after-make-frame-functions with the new frame as arg.
5938
5939*** The new hook window-configuration-change-hook is now run every time
5940the window configuration has changed. The frame whose configuration
5941has changed is the selected frame when the hook is run.
5942
5943*** Each frame now independently records the order for recently
5944selected buffers, in its buffer-list frame parameter, so that the
5945value of other-buffer is now based on the buffers recently displayed
5946in the selected frame.
5947
5948*** The value of the frame parameter vertical-scroll-bars
5949is now `left', `right' or nil. A non-nil value specifies
5950which side of the window to put the scroll bars on.
5951
5952** X Windows features
5953
5954*** You can examine X resources for other applications by binding
5955x-resource-class around a call to x-get-resource. The usual value of
5956x-resource-class is "Emacs", which is the correct value for Emacs.
5957
5958*** In menus, checkboxes and radio buttons now actually work.
5959The menu displays the current status of the box or button.
5960
5961*** The function x-list-fonts now takes an optional fourth argument
5962MAXIMUM which sets a limit on how many matching fonts to return.
5963A smaller value of MAXIMUM makes the function faster.
5964
5965If the only question is whether *any* font matches the pattern,
5966it is good to supply 1 for this argument.
5967
5968** Subprocess features
5969
5970*** A reminder: it is no longer necessary for subprocess filter
5971functions and sentinels to do save-match-data, because Emacs does this
5972automatically.
5973
5974*** The new function shell-command-to-string executes a shell command
5975and returns the output from the command as a string.
5976
5977*** The new function process-contact returns t for a child process,
5978and (HOSTNAME SERVICE) for a net connection.
5979
5980** An error in running pre-command-hook or post-command-hook
5981does clear the variable to nil. The documentation was wrong before.
5982
5983** In define-key-after, if AFTER is t, the new binding now always goes
5984at the end of the keymap. If the keymap is a menu, this means it
5985goes after the other menu items.
5986
5987** If you have a program that makes several changes in the same area
5988of the buffer, you can use the macro combine-after-change-calls
5989around that Lisp code to make it faster when after-change hooks
5990are in use.
5991
5992The macro arranges to call the after-change functions just once for a
5993series of several changes--if that seems safe.
5994
5995Don't alter the variables after-change-functions and
5996after-change-function within the body of a combine-after-change-calls
5997form.
5998
5999** If you define an abbrev (with define-abbrev) whose EXPANSION
6000is not a string, then the abbrev does not expand in the usual sense,
6001but its hook is still run.
6002
6003** Normally, the Lisp debugger is not used (even if you have enabled it)
6004for errors that are handled by condition-case.
6005
6006If you set debug-on-signal to a non-nil value, then the debugger is called
6007regardless of whether there is a handler for the condition. This is
6008useful for debugging problems that happen inside of a condition-case.
6009
6010This mode of operation seems to be unreliable in other ways. Errors that
6011are normal and ought to be handled, perhaps in timers or process
6012filters, will instead invoke the debugger. So don't say you weren't
6013warned.
6014
6015** The new variable ring-bell-function lets you specify your own
6016way for Emacs to "ring the bell".
6017
6018** If run-at-time's TIME argument is t, the action is repeated at
6019integral multiples of REPEAT from the epoch; this is useful for
6020functions like display-time.
6021
6022** You can use the function locate-library to find the precise file
6023name of a Lisp library. This isn't new, but wasn't documented before.
6024
6025** Commands for entering view mode have new optional arguments that
6026can be used from Lisp. Low-level entrance to and exit from view mode
6027is done by functions view-mode-enter and view-mode-exit.
6028
6029** batch-byte-compile-file now makes Emacs return a nonzero status code
6030if there is an error in compilation.
6031
6032** pop-to-buffer, switch-to-buffer-other-window and
6033switch-to-buffer-other-frame now accept an additional optional
6034argument NORECORD, much like switch-to-buffer. If it is non-nil,
6035they don't put the buffer at the front of the buffer list.
6036
6037** If your .emacs file leaves the *scratch* buffer non-empty,
6038Emacs does not display the startup message, so as to avoid changing
6039the *scratch* buffer.
6040
6041** The new function regexp-opt returns an efficient regexp to match a string.
6042The arguments are STRINGS and (optionally) PAREN. This function can be used
6043where regexp matching or searching is intensively used and speed is important,
6044e.g., in Font Lock mode.
6045
6046** The variable buffer-display-count is local to each buffer,
6047and is incremented each time the buffer is displayed in a window.
6048It starts at 0 when the buffer is created.
6049
6050** The new function compose-mail starts composing a mail message
6051using the user's chosen mail composition agent (specified with the
6052variable mail-user-agent). It has variants compose-mail-other-window
6053and compose-mail-other-frame.
6054
6055** The `user-full-name' function now takes an optional parameter which
6056can either be a number (the UID) or a string (the login name). The
6057full name of the specified user will be returned.
6058
6059** Lisp packages that load files of customizations, or any other sort
6060of user profile, should obey the variable init-file-user in deciding
6061where to find it. They should load the profile of the user name found
6062in that variable. If init-file-user is nil, meaning that the -q
6063option was used, then Lisp packages should not load the customization
6064files at all.
6065
6066** format-time-string now allows you to specify the field width
6067and type of padding. This works as in printf: you write the field
6068width as digits in the middle of a %-construct. If you start
6069the field width with 0, it means to pad with zeros.
6070
6071For example, %S normally specifies the number of seconds since the
6072minute; %03S means to pad this with zeros to 3 positions, %_3S to pad
6073with spaces to 3 positions. Plain %3S pads with zeros, because that
6074is how %S normally pads to two positions.
6075
6076** thing-at-point now supports a new kind of "thing": url.
6077
6078** imenu.el changes.
6079
6080You can now specify a function to be run when selecting an
6081item from menu created by imenu.
6082
6083An example of using this feature: if we define imenu items for the
6084#include directives in a C file, we can open the included file when we
6085select one of those items.
6086\f
6087* Emacs 19.34 is a bug-fix release with no user-visible changes.
6088\f
6089* Changes in Emacs 19.33.
6090
6091** Bibtex mode no longer turns on Auto Fill automatically. (No major
6092mode should do that--it is the user's choice.)
6093
6094** The variable normal-auto-fill-function specifies the function to
6095use for auto-fill-function, if and when Auto Fill is turned on.
6096Major modes can set this locally to alter how Auto Fill works.
6097\f
6098* Editing Changes in Emacs 19.32
6099
6100** C-x f with no argument now signals an error.
6101To set the fill column at the current column, use C-u C-x f.
6102
6103** Expanding dynamic abbrevs with M-/ is now smarter about case
6104conversion. If you type the abbreviation with mixed case, and it
6105matches the beginning of the expansion including case, then the
6106expansion is copied verbatim. Using SPC M-/ to copy an additional
6107word always copies it verbatim except when the previous copied word is
6108all caps.
6109
6110** On a non-windowing terminal, which can display only one Emacs frame
6111at a time, creating a new frame with C-x 5 2 also selects that frame.
6112
6113When using a display that can show multiple frames at once, C-x 5 2
6114does make the frame visible, but does not select it. This is the same
6115as in previous Emacs versions.
6116
6117** You can use C-x 5 2 to create multiple frames on MSDOS, just as on a
6118non-X terminal on Unix. Of course, only one frame is visible at any
6119time, since your terminal doesn't have the ability to display multiple
6120frames.
6121
6122** On Windows, set win32-pass-alt-to-system to a non-nil value
6123if you would like tapping the Alt key to invoke the Windows menu.
6124This feature is not enabled by default; since the Alt key is also the
6125Meta key, it is too easy and painful to activate this feature by
6126accident.
6127
6128** The command apply-macro-to-region-lines repeats the last defined
6129keyboard macro once for each complete line within the current region.
6130It does this line by line, by moving point to the beginning of that
6131line and then executing the macro.
6132
6133This command is not new, but was never documented before.
6134
6135** You can now use Mouse-1 to place the region around a string constant
6136(something surrounded by doublequote characters or other delimiter
6137characters of like syntax) by double-clicking on one of the delimiting
6138characters.
6139
6140** Font Lock mode
6141
6142*** Font Lock support modes
6143
6144Font Lock can be configured to use Fast Lock mode and Lazy Lock mode (see
6145below) in a flexible way. Rather than adding the appropriate function to the
6146hook font-lock-mode-hook, you can use the new variable font-lock-support-mode
6147to control which modes have Fast Lock mode or Lazy Lock mode turned on when
6148Font Lock mode is enabled.
6149
6150For example, to use Fast Lock mode when Font Lock mode is turned on, put:
6151
6152 (setq font-lock-support-mode 'fast-lock-mode)
6153
6154in your ~/.emacs.
6155
6156*** lazy-lock
6157
6158The lazy-lock package speeds up Font Lock mode by making fontification occur
6159only when necessary, such as when a previously unfontified part of the buffer
6160becomes visible in a window. When you create a buffer with Font Lock mode and
6161Lazy Lock mode turned on, the buffer is not fontified. When certain events
6162occur (such as scrolling), Lazy Lock makes sure that the visible parts of the
6163buffer are fontified. Lazy Lock also defers on-the-fly fontification until
6164Emacs has been idle for a given amount of time.
6165
6166To use this package, put in your ~/.emacs:
6167
6168 (setq font-lock-support-mode 'lazy-lock-mode)
6169
6170To control the package behaviour, see the documentation for `lazy-lock-mode'.
6171
6172** Changes in BibTeX mode.
6173
6174*** For all entries allow spaces and tabs between opening brace or
6175paren and key.
6176
6177*** Non-escaped double-quoted characters (as in `Sch"of') are now
6178supported.
6179
6180** Gnus changes.
6181
6182Gnus, the Emacs news reader, has undergone further rewriting. Many new
6183commands and variables have been added. There should be no
6184significant incompatibilities between this Gnus version and the
6185previously released version, except in the message composition area.
6186
6187Below is a list of the more user-visible changes. Coding changes
6188between Gnus 5.1 and 5.2 are more extensive.
6189
6190*** A new message composition mode is used. All old customization
6191variables for mail-mode, rnews-reply-mode and gnus-msg are now
6192obsolete.
6193
6194*** Gnus is now able to generate "sparse" threads -- threads where
6195missing articles are represented by empty nodes.
6196
6197 (setq gnus-build-sparse-threads 'some)
6198
6199*** Outgoing articles are stored on a special archive server.
6200
6201 To disable this: (setq gnus-message-archive-group nil)
6202
6203*** Partial thread regeneration now happens when articles are
6204referred.
6205
6206*** Gnus can make use of GroupLens predictions:
6207
6208 (setq gnus-use-grouplens t)
6209
6210*** A trn-line tree buffer can be displayed.
6211
6212 (setq gnus-use-trees t)
6213
6214*** An nn-like pick-and-read minor mode is available for the summary
6215buffers.
6216
6217 (add-hook 'gnus-summary-mode-hook 'gnus-pick-mode)
6218
6219*** In binary groups you can use a special binary minor mode:
6220
6221 `M-x gnus-binary-mode'
6222
6223*** Groups can be grouped in a folding topic hierarchy.
6224
6225 (add-hook 'gnus-group-mode-hook 'gnus-topic-mode)
6226
6227*** Gnus can re-send and bounce mail.
6228
6229 Use the `S D r' and `S D b'.
6230
6231*** Groups can now have a score, and bubbling based on entry frequency
6232is possible.
6233
6234 (add-hook 'gnus-summary-exit-hook 'gnus-summary-bubble-group)
6235
6236*** Groups can be process-marked, and commands can be performed on
6237groups of groups.
6238
6239*** Caching is possible in virtual groups.
6240
6241*** nndoc now understands all kinds of digests, mail boxes, rnews news
6242batches, ClariNet briefs collections, and just about everything else.
6243
6244*** Gnus has a new backend (nnsoup) to create/read SOUP packets.
6245
6246*** The Gnus cache is much faster.
6247
6248*** Groups can be sorted according to many criteria.
6249
6250 For instance: (setq gnus-group-sort-function 'gnus-group-sort-by-rank)
6251
6252*** New group parameters have been introduced to set list-address and
6253expiration times.
6254
6255*** All formatting specs allow specifying faces to be used.
6256
6257*** There are several more commands for setting/removing/acting on
6258process marked articles on the `M P' submap.
6259
6260*** The summary buffer can be limited to show parts of the available
6261articles based on a wide range of criteria. These commands have been
6262bound to keys on the `/' submap.
6263
6264*** Articles can be made persistent -- as an alternative to saving
6265articles with the `*' command.
6266
6267*** All functions for hiding article elements are now toggles.
6268
6269*** Article headers can be buttonized.
6270
6271 (add-hook 'gnus-article-display-hook 'gnus-article-add-buttons-to-head)
6272
6273*** All mail backends support fetching articles by Message-ID.
6274
6275*** Duplicate mail can now be treated properly. See the
6276`nnmail-treat-duplicates' variable.
6277
6278*** All summary mode commands are available directly from the article
6279buffer.
6280
6281*** Frames can be part of `gnus-buffer-configuration'.
6282
6283*** Mail can be re-scanned by a daemonic process.
6284
6285*** Gnus can make use of NoCeM files to filter spam.
6286
6287 (setq gnus-use-nocem t)
6288
6289*** Groups can be made permanently visible.
6290
6291 (setq gnus-permanently-visible-groups "^nnml:")
6292
6293*** Many new hooks have been introduced to make customizing easier.
6294
6295*** Gnus respects the Mail-Copies-To header.
6296
6297*** Threads can be gathered by looking at the References header.
6298
6299 (setq gnus-summary-thread-gathering-function
6300 'gnus-gather-threads-by-references)
6301
6302*** Read articles can be stored in a special backlog buffer to avoid
6303refetching.
6304
6305 (setq gnus-keep-backlog 50)
6306
6307*** A clean copy of the current article is always stored in a separate
6308buffer to allow easier treatment.
6309
6310*** Gnus can suggest where to save articles. See `gnus-split-methods'.
6311
6312*** Gnus doesn't have to do as much prompting when saving.
6313
6314 (setq gnus-prompt-before-saving t)
6315
6316*** gnus-uu can view decoded files asynchronously while fetching
6317articles.
6318
6319 (setq gnus-uu-grabbed-file-functions 'gnus-uu-grab-view)
6320
6321*** Filling in the article buffer now works properly on cited text.
6322
6323*** Hiding cited text adds buttons to toggle hiding, and how much
6324cited text to hide is now customizable.
6325
6326 (setq gnus-cited-lines-visible 2)
6327
6328*** Boring headers can be hidden.
6329
6330 (add-hook 'gnus-article-display-hook 'gnus-article-hide-boring-headers)
6331
6332*** Default scoring values can now be set from the menu bar.
6333
6334*** Further syntax checking of outgoing articles have been added.
6335
6336The Gnus manual has been expanded. It explains all these new features
6337in greater detail.
6338\f
6339* Lisp Changes in Emacs 19.32
6340
6341** The function set-visited-file-name now accepts an optional
6342second argument NO-QUERY. If it is non-nil, then the user is not
6343asked for confirmation in the case where the specified file already
6344exists.
6345
6346** The variable print-length applies to printing vectors and bitvectors,
6347as well as lists.
6348
6349** The new function keymap-parent returns the parent keymap
6350of a given keymap.
6351
6352** The new function set-keymap-parent specifies a new parent for a
6353given keymap. The arguments are KEYMAP and PARENT. PARENT must be a
6354keymap or nil.
6355
6356** Sometimes menu keymaps use a command name, a symbol, which is really
6357an automatically generated alias for some other command, the "real"
6358name. In such a case, you should give that alias symbol a non-nil
6359menu-alias property. That property tells the menu system to look for
6360equivalent keys for the real name instead of equivalent keys for the
6361alias.
6362\f
6363* Editing Changes in Emacs 19.31
6364
6365** Freedom of the press restricted in the United States.
6366
6367Emacs has been censored in accord with the Communications Decency Act.
6368This includes removing some features of the doctor program. That law
6369was described by its supporters as a ban on pornography, but it bans
6370far more than that. The Emacs distribution has never contained any
6371pornography, but parts of it were nonetheless prohibited.
6372
6373For information on US government censorship of the Internet, and what
6374you can do to bring back freedom of the press, see the web site
6375`http://www.vtw.org/'.
6376
6377** A note about C mode indentation customization.
6378
6379The old (Emacs 19.29) ways of specifying a C indentation style
6380do not normally work in the new implementation of C mode.
6381It has its own methods of customizing indentation, which are
6382much more powerful than the old C mode. See the Editing Programs
6383chapter of the manual for details.
6384
6385However, you can load the library cc-compat to make the old
6386customization variables take effect.
6387
6388** Marking with the mouse.
6389
6390When you mark a region with the mouse, the region now remains
6391highlighted until the next input event, regardless of whether you are
6392using M-x transient-mark-mode.
6393
6394** Improved Windows NT/95 support.
6395
6396*** Emacs now supports scroll bars on Windows NT and Windows 95.
6397
6398*** Emacs now supports subprocesses on Windows 95. (Subprocesses used
6399to work on NT only and not on 95.)
6400
6401*** There are difficulties with subprocesses, though, due to problems
6402in Windows, beyond the control of Emacs. They work fine as long as
6403you run Windows applications. The problems arise when you run a DOS
6404application in a subprocesses. Since current shells run as DOS
6405applications, these problems are significant.
6406
6407If you run a DOS application in a subprocess, then the application is
6408likely to busy-wait, which means that your machine will be 100% busy.
6409However, if you don't mind the temporary heavy load, the subprocess
6410will work OK as long as you tell it to terminate before you start any
6411other DOS application as a subprocess.
6412
6413Emacs is unable to terminate or interrupt a DOS subprocess.
6414You have to do this by providing input directly to the subprocess.
6415
6416If you run two DOS applications at the same time in two separate
6417subprocesses, even if one of them is asynchronous, you will probably
6418have to reboot your machine--until then, it will remain 100% busy.
6419Windows simply does not cope when one Windows process tries to run two
6420separate DOS subprocesses. Typing CTL-ALT-DEL and then choosing
6421Shutdown seems to work although it may take a few minutes.
6422
6423** M-x resize-minibuffer-mode.
6424
6425This command, not previously mentioned in NEWS, toggles a mode in
6426which the minibuffer window expands to show as many lines as the
6427minibuffer contains.
6428
6429** `title' frame parameter and resource.
6430
6431The `title' X resource now specifies just the frame title, nothing else.
6432It does not affect the name used for looking up other X resources.
6433It works by setting the new `title' frame parameter, which likewise
6434affects just the displayed title of the frame.
6435
6436The `name' parameter continues to do what it used to do:
6437it specifies the frame name for looking up X resources,
6438and also serves as the default for the displayed title
6439when the `title' parameter is unspecified or nil.
6440
6441** Emacs now uses the X toolkit by default, if you have a new
6442enough version of X installed (X11R5 or newer).
6443
6444** When you compile Emacs with the Motif widget set, Motif handles the
6445F10 key by activating the menu bar. To avoid confusion, the usual
6446Emacs binding of F10 is replaced with a no-op when using Motif.
6447
6448If you want to be able to use F10 in Emacs, you can rebind the Motif
6449menubar to some other key which you don't use. To do so, add
6450something like this to your X resources file. This example rebinds
6451the Motif menu bar activation key to S-F12:
6452
6453 Emacs*defaultVirtualBindings: osfMenuBar : Shift<Key>F12
6454
6455** In overwrite mode, DEL now inserts spaces in most cases
6456to replace the characters it "deletes".
6457
6458** The Rmail summary now shows the number of lines in each message.
6459
6460** Rmail has a new command M-x unforward-rmail-message, which extracts
6461a forwarded message from the message that forwarded it. To use it,
6462select a message which contains a forwarded message and then type the command.
6463It inserts the forwarded message as a separate Rmail message
6464immediately after the selected one.
6465
6466This command also undoes the textual modifications that are standardly
6467made, as part of forwarding, by Rmail and other mail reader programs.
6468
6469** Turning off saving of .saves-... files in your home directory.
6470
6471Each Emacs session writes a file named .saves-... in your home
6472directory to record which files M-x recover-session should recover.
6473If you exit Emacs normally with C-x C-c, it deletes that file. If
6474Emacs or the operating system crashes, the file remains for M-x
6475recover-session.
6476
6477You can turn off the writing of these files by setting
6478auto-save-list-file-name to nil. If you do this, M-x recover-session
6479will not work.
6480
6481Some previous Emacs versions failed to delete these files even on
6482normal exit. This is fixed now. If you are thinking of turning off
6483this feature because of past experiences with versions that had this
6484bug, it would make sense to check whether you still want to do so
6485now that the bug is fixed.
6486
6487** Changes to Version Control (VC)
6488
6489There is a new variable, vc-follow-symlinks. It indicates what to do
6490when you visit a link to a file that is under version control.
6491Editing the file through the link bypasses the version control system,
6492which is dangerous and probably not what you want.
6493
6494If this variable is t, VC follows the link and visits the real file,
6495telling you about it in the echo area. If it is `ask' (the default),
6496VC asks for confirmation whether it should follow the link. If nil,
6497the link is visited and a warning displayed.
6498
6499** iso-acc.el now lets you specify a choice of language.
6500Languages include "latin-1" (the default) and "latin-2" (which
6501is designed for entering ISO Latin-2 characters).
6502
6503There are also choices for specific human languages such as French and
6504Portuguese. These are subsets of Latin-1, which differ in that they
6505enable only the accent characters needed for particular language.
6506The other accent characters, not needed for the chosen language,
6507remain normal.
6508
6509** Posting articles and sending mail now has M-TAB completion on various
6510header fields (Newsgroups, To, CC, ...).
6511
6512Completion in the Newsgroups header depends on the list of groups
6513known to your news reader. Completion in the Followup-To header
6514offers those groups which are in the Newsgroups header, since
6515Followup-To usually just holds one of those.
6516
6517Completion in fields that hold mail addresses works based on the list
6518of local users plus your aliases. Additionally, if your site provides
6519a mail directory or a specific host to use for any unrecognized user
6520name, you can arrange to query that host for completion also. (See the
6521documentation of variables `mail-directory-process' and
6522`mail-directory-stream'.)
6523
6524** A greatly extended sgml-mode offers new features such as (to be configured)
6525skeletons with completing read for tags and attributes, typing named
6526characters including optionally all 8bit characters, making tags invisible
6527with optional alternate display text, skipping and deleting tag(pair)s.
6528
6529Note: since Emacs' syntax feature cannot limit the special meaning of ', " and
6530- to inside <>, for some texts the result, especially of font locking, may be
6531wrong (see `sgml-specials' if you get wrong results).
6532
6533The derived html-mode configures this with tags and attributes more or
6534less HTML3ish. It also offers optional quick keys like C-c 1 for
6535headline or C-c u for unordered list (see `html-quick-keys'). Edit /
6536Text Properties / Face or M-g combinations create tags as applicable.
6537Outline minor mode is supported and level 1 font-locking tries to
6538fontify tag contents (which only works when they fit on one line, due
6539to a limitation in font-lock).
6540
6541External viewing via browse-url can occur automatically upon saving.
6542
6543** M-x imenu-add-to-menubar now adds to the menu bar for the current
6544buffer only. If you want to put an Imenu item in the menu bar for all
6545buffers that use a particular major mode, use the mode hook, as in
6546this example:
6547
6548 (add-hook 'emacs-lisp-mode-hook
6549 '(lambda () (imenu-add-to-menubar "Index")))
6550
6551** Changes in BibTeX mode.
6552
6553*** Field names may now contain digits, hyphens, and underscores.
6554
6555*** Font Lock mode is now supported.
6556
6557*** bibtex-make-optional-field is no longer interactive.
6558
6559*** If bibtex-maintain-sorted-entries is non-nil, inserting new
6560entries is now done with a faster algorithm. However, inserting
6561will fail in this case if the buffer contains invalid entries or
6562isn't in sorted order, so you should finish each entry with C-c C-c
6563(bibtex-close-entry) after you have inserted or modified it.
6564The default value of bibtex-maintain-sorted-entries is nil.
6565
6566*** Function `show-all' is no longer bound to a key, since C-u C-c C-q
6567does the same job.
6568
6569*** Entries with quotes inside quote-delimited fields (as `author =
6570"Stefan Sch{\"o}f"') are now supported.
6571
6572*** Case in field names doesn't matter anymore when searching for help
6573text.
6574
6575** Font Lock mode
6576
6577*** Global Font Lock mode
6578
6579Font Lock mode can be turned on globally, in buffers that support it, by the
6580new command global-font-lock-mode. You can use the new variable
6581font-lock-global-modes to control which modes have Font Lock mode automagically
6582turned on. By default, this variable is set so that Font Lock mode is turned
6583on globally where the buffer mode supports it.
6584
6585For example, to automagically turn on Font Lock mode where supported, put:
6586
6587 (global-font-lock-mode t)
6588
6589in your ~/.emacs.
6590
6591*** Local Refontification
6592
6593In Font Lock mode, editing a line automatically refontifies that line only.
6594However, if your change alters the syntactic context for following lines,
6595those lines remain incorrectly fontified. To refontify them, use the new
6596command M-g M-g (font-lock-fontify-block).
6597
6598In certain major modes, M-g M-g refontifies the entire current function.
6599(The variable font-lock-mark-block-function controls how to find the
6600current function.) In other major modes, M-g M-g refontifies 16 lines
6601above and below point.
6602
6603With a prefix argument N, M-g M-g refontifies N lines above and below point.
6604
6605** Follow mode
6606
6607Follow mode is a new minor mode combining windows showing the same
6608buffer into one tall "virtual window". The windows are typically two
6609side-by-side windows. Follow mode makes them scroll together as if
6610they were a unit. To use it, go to a frame with just one window,
6611split it into two side-by-side windows using C-x 3, and then type M-x
6612follow-mode.
6613
6614M-x follow-mode turns off Follow mode if it is already enabled.
6615
6616To display two side-by-side windows and activate Follow mode, use the
6617command M-x follow-delete-other-windows-and-split.
6618
6619** hide-show changes.
6620
6621The hooks hs-hide-hooks and hs-show-hooks have been renamed
6622to hs-hide-hook and hs-show-hook, to follow the convention for
6623normal hooks.
6624
6625** Simula mode now has a menu containing the most important commands.
6626The new command simula-indent-exp is bound to C-M-q.
6627
6628** etags can now handle programs written in Erlang. Files are
6629recognised by the extensions .erl and .hrl. The tagged lines are
6630those that begin a function, record, or macro.
6631
6632** MSDOS Changes
6633
6634*** It is now possible to compile Emacs with the version 2 of DJGPP.
6635Compilation with DJGPP version 1 also still works.
6636
6637*** The documentation of DOS-specific aspects of Emacs was rewritten
6638and expanded; see the ``MS-DOS'' node in the on-line docs.
6639
6640*** Emacs now uses ~ for backup file names, not .bak.
6641
6642*** You can simulate mouse-3 on two-button mice by simultaneously
6643pressing both mouse buttons.
6644
6645*** A number of packages and commands which previously failed or had
6646restricted functionality on MS-DOS, now work. The most important ones
6647are:
6648
6649**** Printing (both with `M-x lpr-buffer' and with `ps-print' package)
6650now works.
6651
6652**** `Ediff' works (in a single-frame mode).
6653
6654**** `M-x display-time' can be used on MS-DOS (due to the new
6655implementation of Emacs timers, see below).
6656
6657**** `Dired' supports Unix-style shell wildcards.
6658
6659**** The `c-macro-expand' command now works as on other platforms.
6660
6661**** `M-x recover-session' works.
6662
6663**** `M-x list-colors-display' displays all the available colors.
6664
6665**** The `TPU-EDT' package works.
6666\f
6667* Lisp changes in Emacs 19.31.
6668
6669** The function using-unix-filesystems on Windows NT and Windows 95
6670tells Emacs to read and write files assuming that they reside on a
6671remote Unix filesystem. No CR/LF translation is done on any files in
6672this case. Invoking using-unix-filesystems with t activates this
6673behavior, and invoking it with any other value deactivates it.
6674
6675** Change in system-type and system-configuration values.
6676
6677The value of system-type on a Linux-based GNU system is now `lignux',
6678not `linux'. This means that some programs which use `system-type'
6679need to be changed. The value of `system-configuration' will also
6680be different.
6681
6682It is generally recommended to use `system-configuration' rather
6683than `system-type'.
6684
6685See the file LINUX-GNU in this directory for more about this.
6686
6687** The functions shell-command and dired-call-process
6688now run file name handlers for default-directory, if it has them.
6689
6690** Undoing the deletion of text now restores the positions of markers
6691that pointed into or next to the deleted text.
6692
6693** Timers created with run-at-time now work internally to Emacs, and
6694no longer use a separate process. Therefore, they now work more
6695reliably and can be used for shorter time delays.
6696
6697The new function run-with-timer is a convenient way to set up a timer
6698to run a specified amount of time after the present. A call looks
6699like this:
6700
6701 (run-with-timer SECS REPEAT FUNCTION ARGS...)
6702
6703SECS says how many seconds should elapse before the timer happens.
6704It may be an integer or a floating point number. When the timer
6705becomes ripe, the action is to call FUNCTION with arguments ARGS.
6706
6707REPEAT gives the interval for repeating the timer (measured in
6708seconds). It may be an integer or a floating point number. nil or 0
6709means don't repeat at all--call FUNCTION just once.
6710
6711*** with-timeout provides an easy way to do something but give
6712up if too much time passes.
6713
6714 (with-timeout (SECONDS TIMEOUT-FORMS...) BODY...)
6715
6716This executes BODY, but gives up after SECONDS seconds.
6717If it gives up, it runs the TIMEOUT-FORMS and returns the value
6718of the last one of them. Normally it returns the value of the last
6719form in BODY.
6720
6721*** You can now arrange to call a function whenever Emacs is idle for
6722a certain length of time. To do this, call run-with-idle-timer. A
6723call looks like this:
6724
6725 (run-with-idle-timer SECS REPEAT FUNCTION ARGS...)
6726
6727SECS says how many seconds of idleness should elapse before the timer
6728runs. It may be an integer or a floating point number. When the
6729timer becomes ripe, the action is to call FUNCTION with arguments
6730ARGS.
6731
6732Emacs becomes idle whenever it finishes executing a keyboard or mouse
6733command. It remains idle until it receives another keyboard or mouse
6734command.
6735
6736REPEAT, if non-nil, means this timer should be activated again each
6737time Emacs becomes idle and remains idle for SECS seconds The timer
6738does not repeat if Emacs *remains* idle; it runs at most once after
6739each time Emacs becomes idle.
6740
6741If REPEAT is nil, the timer runs just once, the first time Emacs is
6742idle for SECS seconds.
6743
6744*** post-command-idle-hook is now obsolete; you shouldn't use it at
6745all, because it interferes with the idle timer mechanism. If your
6746programs use post-command-idle-hook, convert them to use idle timers
6747instead.
6748
6749*** y-or-n-p-with-timeout lets you ask a question but give up if
6750there is no answer within a certain time.
6751
6752 (y-or-n-p-with-timeout PROMPT SECONDS DEFAULT-VALUE)
6753
6754asks the question PROMPT (just like y-or-n-p). If the user answers
6755within SECONDS seconds, it returns the answer that the user gave.
6756Otherwise it gives up after SECONDS seconds, and returns DEFAULT-VALUE.
6757
6758** Minor change to `encode-time': you can now pass more than seven
6759arguments. If you do that, the first six arguments have the usual
6760meaning, the last argument is interpreted as the time zone, and the
6761arguments in between are ignored.
6762
6763This means that it works to use the list returned by `decode-time' as
6764the list of arguments for `encode-time'.
6765
6766** The default value of load-path now includes the directory
6767/usr/local/share/emacs/VERSION/site-lisp In addition to
6768/usr/local/share/emacs/site-lisp. You can use this new directory for
6769site-specific Lisp packages that belong with a particular Emacs
6770version.
6771
6772It is not unusual for a Lisp package that works well in one Emacs
6773version to cause trouble in another. Sometimes packages need updating
6774for incompatible changes; sometimes they look at internal data that
6775has changed; sometimes the package has been installed in Emacs itself
6776and the installed version should be used. Whatever the reason for the
6777problem, this new feature makes it easier to solve.
6778
6779** When your program contains a fixed file name (like .completions or
6780.abbrev.defs), the file name usually needs to be different on operating
6781systems with limited file name syntax.
6782
6783Now you can avoid ad-hoc conditionals by using the function
6784convert-standard-filename to convert the file name to a proper form
6785for each operating system. Here is an example of use, from the file
6786completions.el:
6787
6788(defvar save-completions-file-name
6789 (convert-standard-filename "~/.completions")
6790 "*The filename to save completions to.")
6791
6792This sets the variable save-completions-file-name to a value that
6793depends on the operating system, because the definition of
6794convert-standard-filename depends on the operating system. On
6795Unix-like systems, it returns the specified file name unchanged. On
6796MS-DOS, it adapts the name to fit the limitations of that system.
6797
6798** The interactive spec N now returns the numeric prefix argument
6799rather than the raw prefix argument. (It still reads a number using the
6800minibuffer if there is no prefix argument at all.)
6801
6802** When a process is deleted, this no longer disconnects the process
6803marker from its buffer position.
6804
6805** The variable garbage-collection-messages now controls whether
6806Emacs displays a message at the beginning and end of garbage collection.
6807The default is nil, meaning there are no messages.
6808
6809** The variable debug-ignored-errors specifies certain kinds of errors
6810that should not enter the debugger. Its value is a list of error
6811condition symbols and/or regular expressions. If the error has any
6812of the condition symbols listed, or if any of the regular expressions
6813matches the error message, then that error does not enter the debugger,
6814regardless of the value of debug-on-error.
6815
6816This variable is initialized to match certain common but uninteresting
6817errors that happen often during editing.
6818
6819** The new function error-message-string converts an error datum
6820into its error message. The error datum is what condition-case
6821puts into the variable, to describe the error that happened.
6822
6823** Anything that changes which buffer appears in a given window
6824now runs the window-scroll-functions for that window.
6825
6826** The new function get-buffer-window-list returns a list of windows displaying
6827a buffer. The function is called with the buffer (a buffer object or a buffer
6828name) and two optional arguments specifying the minibuffer windows and frames
6829to search. Therefore this function takes optional args like next-window etc.,
6830and not get-buffer-window.
6831
6832** buffer-substring now runs the hook buffer-access-fontify-functions,
6833calling each function with two arguments--the range of the buffer
6834being accessed. buffer-substring-no-properties does not call them.
6835
6836If you use this feature, you should set the variable
6837buffer-access-fontified-property to a non-nil symbol, which is a
6838property name. Then, if all the characters in the buffer range have a
6839non-nil value for that property, the buffer-access-fontify-functions
6840are not called. When called, these functions should put a non-nil
6841property on the text that they fontify, so that they won't get called
6842over and over for the same text.
6843
6844** Changes in lisp-mnt.el
6845
6846*** The lisp-mnt package can now recognize file headers that are written
6847in the formats used by the `what' command and the RCS `ident' command:
6848
6849;; @(#) HEADER: text
6850;; $HEADER: text $
6851
6852in addition to the normal
6853
6854;; HEADER: text
6855
6856*** The commands lm-verify and lm-synopsis are now interactive. lm-verify
6857checks that the library file has proper sections and headers, and
6858lm-synopsis extracts first line "synopsis'"information.
6859\f
6860* For older news, see the file ONEWS.
6861
6862----------------------------------------------------------------------
6863Copyright information:
6864
6865Copyright (C) 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
6866
6867 Permission is granted to anyone to make or distribute verbatim copies
6868 of this document as received, in any medium, provided that the
6869 copyright notice and this permission notice are preserved,
6870 thus giving the recipient permission to redistribute in turn.
6871
6872 Permission is granted to distribute modified versions
6873 of this document, or of portions of it,
6874 under the above conditions, provided also that they
6875 carry prominent notices stating who last changed them.
6876\f
6877Local variables:
6878mode: outline
6879paragraph-separate: "[ \f]*$"
6880end: