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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** New language environments `Latin-8' and `Latin-9'.
381These correspond respectively to the ISO character sets 8859-14
382(Celtic) and 8859-15 (updated Latin-1, with the Euro sign). There is
383currently no specific input method support for them.
384
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385** New modes and packages
386
387*** 5x5.el is a simple puzzle game.
388
389*** hl-line.el provides a minor mode to highlight the current line.
390
391*** ansi-color.el translates ANSI terminal escapes into text-properties.
392
393*** delphi.el provides a major mode for editing the Delphi (Object
394Pascal) language.
395
396*** quickurl.el provides a simple method of inserting a URL based on
397the text at point.
398
399*** sql.el provides an interface to SQL data bases.
400
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401*** fortune.el uses the fortune program to create mail/news signatures.
402
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403*** whitespace.el ???
404
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405*** PostScript mode (ps-mode) is a new major mode for editing PostScript
406files. It offers: interaction with a PostScript interpreter, including
407(very basic) error handling; fontification, easily customizable for
408interpreter messages; auto-indentation; insertion of EPSF templates and
409often used code snippets; viewing of BoundingBox; commenting out /
410uncommenting regions; conversion of 8bit characters to PostScript octal
411codes. All functionality is accessible through a menu.
412
413*** delim-col helps to prettify columns in a text region or rectangle.
414
415Here is an example of columns:
416
417horse apple bus
418dog pineapple car EXTRA
419porcupine strawberry airplane
420
421Doing the following settings:
422
423 (setq delimit-columns-str-before "[ ")
424 (setq delimit-columns-str-after " ]")
425 (setq delimit-columns-str-separator ", ")
426 (setq delimit-columns-separator "\t")
427
428
429Selecting the lines above and typing:
430
431 M-x delimit-columns-region
432
433It results:
434
435[ horse , apple , bus , ]
436[ dog , pineapple , car , EXTRA ]
437[ porcupine, strawberry, airplane, ]
438
439delim-col has the following options:
440
441 delimit-columns-str-before Specify a string to be inserted
442 before all columns.
443
444 delimit-columns-str-separator Specify a string to be inserted
445 between each column.
446
447 delimit-columns-str-after Specify a string to be inserted
448 after all columns.
449
450 delimit-columns-separator Specify a regexp which separates
451 each column.
452
453delim-col has the following commands:
454
455 delimit-columns-region Prettify all columns in a text region.
456 delimit-columns-rectangle Prettify all columns in a text rectangle.
457
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458*** The package recentf.el maintains a menu for visiting files that
459were operated on recently. When enabled, a new "Open Recent" submenu
460is displayed in the "Files" menu.
461
462The recent files list is automatically saved across Emacs sessions.
463
464To enable/disable recentf use M-x recentf-mode.
465
466To enable recentf at Emacs startup use
467M-x customize-variable RET recentf-mode RET.
468
469To change the number of recent files displayed and others options use
470M-x customize-group RET recentf RET.
471
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472** Withdrawn packages
473
474*** mldrag.el has been removed. mouse.el provides the same
475functionality with aliases for the mldrag functions.
476\f
477* Lisp changes in Emacs 21.1 (see following page for display-related features)
478
479Note that +++ before an item means the Lisp manual has been updated.
480--- means that I have decided it does not need to be in the Lisp manual.
481When you add a new item, please add it without either +++ or ---
482so I will know I still need to look at it -- rms.
483
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484** syntax tables now understand nested comments.
485To declare a comment syntax as allowing nesting, just add an `n'
486modifier to either of the characters of the comment end and the comment
487start sequences.
488
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489** The function `pixmap-spec-p' has been renamed `bitmap-spec-p'
490because `bitmap' is more in line with the usual X terminology.
491
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492** New function `propertize'
493
494The new function `propertize' can be used to conveniently construct
495strings with text properties.
496
497- Function: propertize STRING &rest PROPERTIES
498
499Value is a copy of STRING with text properties assigned as specified
500by PROPERTIES. PROPERTIES is a sequence of pairs PROPERTY VALUE, with
501PROPERTY being the name of a text property and VALUE being the
502specified value of that property. Example:
503
504 (propertize "foo" 'face 'bold 'read-only t)
505
506+++
507** push and pop macros.
508
509A simple version of the push and pop macros of Common Lisp
510is now defined in Emacs Lisp. These macros allow only symbols
511as the place that holds the list to be changed.
512
513(push NEWELT LISTNAME) add NEWELT to the front of LISTNAME's value.
514(pop LISTNAME) return first elt of LISTNAME, and remove it
515 (thus altering the value of LISTNAME).
516
517+++
518** Regular expressions now support Posix character classes such
519as [:alpha:], [:space:] and so on.
520
521[:digit:] matches 0 through 9
522[:cntrl:] matches ASCII control characters
523[:xdigit:] matches 0 through 9, a through f and A through F.
524[:blank:] matches space and tab only
525[:graph:] matches graphic characters--everything except ASCII control chars,
526 space, and DEL.
527[:print:] matches printing characters--everything except ASCII control chars
528 and DEL.
529[:alnum:] matches letters and digits.
530 (But at present, for multibyte characters,
531 it matches anything that has word syntax.)
532[:alpha:] matches letters.
533 (But at present, for multibyte characters,
534 it matches anything that has word syntax.)
535[:ascii:] matches ASCII (unibyte) characters.
536[:nonascii:] matches non-ASCII (multibyte) characters.
537[:lower:] matches anything lower-case.
538[:punct:] matches punctuation.
539 (But at present, for multibyte characters,
540 it matches anything that has non-word syntax.)
541[:space:] matches anything that has whitespace syntax.
542[:upper:] matches anything upper-case.
543[:word:] matches anything that has word syntax.
544
545+++
546** Emacs now has built-in hash tables.
547
548The following functions are defined for hash tables:
549
550- Function: make-hash-table ARGS
551
552The argument list ARGS consists of keyword/argument pairs. All arguments
553are optional. The following arguments are defined:
554
555:test TEST
556
557TEST must be a symbol specifying how to compare keys. Default is `eql'.
558Predefined are `eq', `eql' and `equal'. If TEST is not predefined,
559it must have been defined with `define-hash-table-test'.
560
561:size SIZE
562
563SIZE must be an integer > 0 giving a hint to the implementation how
564many elements will be put in the hash table. Default size is 65.
565
566:rehash-size REHASH-SIZE
567
568REHASH-SIZE specifies by how much to grow a hash table once it becomes
569full. If REHASH-SIZE is an integer, add that to the hash table's old
570size to get the new size. Otherwise, REHASH-SIZE must be a float >
5711.0, and the new size is computed by multiplying REHASH-SIZE with the
572old size. Default rehash size is 1.5.
573
574:rehash-threshold THRESHOLD
575
576THRESHOLD must be a float > 0 and <= 1.0 specifying when to resize the
577hash table. It is resized when the ratio of (number of entries) /
578(size of hash table) is >= THRESHOLD. Default threshold is 0.8.
579
580:weakness WEAK
581
582WEAK must be either nil, one of the symbols `key, `value', or t.
583Entries are removed from weak tables during garbage collection if
584their key and/or value are not referenced elsewhere outside of the
585hash table. Default are non-weak hash tables.
586
587- Function: makehash &optional TEST
588
589Similar to make-hash-table, but only TEST can be specified.
590
591- Function: hash-table-p TABLE
592
593Returns non-nil if TABLE is a hash table object.
594
595- Function: copy-hash-table TABLE
596
597Returns a copy of TABLE. Only the table itself is copied, keys and
598values are shared.
599
600- Function: hash-table-count TABLE
601
602Returns the number of entries in TABLE.
603
604- Function: hash-table-rehash-size TABLE
605
606Returns the rehash size of TABLE.
607
608- Function: hash-table-rehash-threshold TABLE
609
610Returns the rehash threshold of TABLE.
611
612- Function: hash-table-rehash-size TABLE
613
614Returns the size of TABLE.
615
616- Function: hash-table-rehash-test TABLE
617
618Returns the test TABLE uses to compare keys.
619
620- Function: hash-table-weakness TABLE
621
622Returns the weakness specified for TABLE.
623
624- Function: clrhash TABLE
625
626Clear TABLE.
627
628- Function: gethash KEY TABLE &optional DEFAULT
629
630Look up KEY in TABLE and return its associated VALUE or DEFAULT if
631not found.
632
633- Function: puthash KEY VALUE TABLE
634
635Associate KEY with VALUE in TABLE. If KEY is already associated with
636another value, replace the old value with VALUE.
637
638- Function: remhash KEY TABLE
639
640Remove KEY from TABLE if it is there.
641
642- Function: maphash FUNCTION TABLE
643
644Call FUNCTION for all elements in TABLE. FUNCTION must take two
645arguments KEY and VALUE.
646
647- Function: sxhash OBJ
648
649Return a hash code for Lisp object OBJ.
650
651- Function: define-hash-table-test NAME TEST-FN HASH-FN
652
653Define a new hash table test named NAME. If NAME is specified as
654a test in `make-hash-table', the table created will use TEST-FN for
655comparing keys, and HASH-FN to compute hash codes for keys. Test
656and hash function are stored as symbol property `hash-table-test'
657of NAME with a value of (TEST-FN HASH-FN).
658
659TEST-FN must take two arguments and return non-nil if they are the same.
660
661HASH-FN must take one argument and return an integer that is the hash
662code of the argument. The function should use the whole range of
663integer values for hash code computation, including negative integers.
664
665Example: The following creates a hash table whose keys are supposed to
666be strings that are compared case-insensitively.
667
668 (defun case-fold-string= (a b)
669 (compare-strings a nil nil b nil nil t))
670
671 (defun case-fold-string-hash (a)
672 (sxhash (upcase a)))
673
674 (define-hash-table-test 'case-fold 'case-fold-string=
675 'case-fold-string-hash))
676
677 (make-hash-table :test 'case-fold)
678
679+++
680** The Lisp reader handles circular structure.
681
682It now works to use the #N= and #N# constructs to represent
683circular structures. For example, #1=(a . #1#) represents
684a cons cell which is its own cdr.
685
686+++
687** The Lisp printer handles circular structure.
688
689If you bind print-circle to a non-nil value, the Lisp printer outputs
690#N= and #N# constructs to represent circular and shared structure.
691
692You can also do several calls to print functions using a common
693set of #N= constructs; here is how.
694
695 (let ((print-circle t)
696 (print-continuous-numbering t)
697 print-number-table)
698 (print1 ...)
699 (print1 ...)
700 ...)
701
702+++
703** If the second argument to `move-to-column' is anything but nil or
704t, that means replace a tab with spaces if necessary to reach the
705specified column, but do not add spaces at the end of the line if it
706is too short to reach that column.
707
708+++
709** perform-replace has a new feature: the REPLACEMENTS argument may
710now be a cons cell (FUNCTION . DATA). This means to call FUNCTION
711after each match to get the replacement text. FUNCTION is called with
712two arguments: DATA, and the number of replacements already made.
713
714If the FROM-STRING contains any upper-case letters,
715perform-replace also turns off `case-fold-search' temporarily
716and inserts the replacement text without altering case in it.
717
718+++
719** The function buffer-size now accepts an optional argument
720to specify which buffer to return the size of.
721
722+++
723** The calendar motion commands now run the normal hook
724calendar-move-hook after moving point.
725
726+++
727** The new variable small-temporary-file-directory specifies a
728directory to use for creating temporary files that are likely to be
729small. (Certain Emacs features use this directory.) If
730small-temporary-file-directory is nil, they use
731temporary-file-directory instead.
732
733+++
734** The variable `inhibit-modification-hooks', if non-nil, inhibits all
735the hooks that track changes in the buffer. This affects
736`before-change-functions' and `after-change-functions', as well as
737hooks attached to text properties and overlay properties.
738
739+++
740** assoc-delete-all is a new function that deletes all the
741elements of an alist which have a particular value as the car.
742
743+++
744** make-temp-file provides a more reliable way to create a temporary file.
745
746make-temp-file is used like make-temp-name, except that it actually
747creates the file before it returns. This prevents a timing error,
748ensuring that no other job can use the same name for a temporary file.
749
750+++
751** New exclusive-open feature in `write-region'
752
753The optional seventh arg is now called MUSTBENEW. If non-nil, it insists
754on a check for an existing file with the same name. If MUSTBENEW
755is `excl', that means to get an error if the file already exists;
756never overwrite. If MUSTBENEW is neither nil nor `excl', that means
757ask for confirmation before overwriting, but do go ahead and
758overwrite the file if the user gives confirmation.
759
760If the MUSTBENEW argument in `write-region' is `excl',
761that means to use a special feature in the `open' system call
762to get an error if the file exists at that time.
763The error reported is `file-already-exists'.
764
765+++
766** Function `format' now handles text properties.
767
768Text properties of the format string are applied to the result string.
769If the result string is longer than the format string, text properties
770ending at the end of the format string are extended to the end of the
771result string.
772
773Text properties from string arguments are applied to the result
774string where arguments appear in the result string.
775
776Example:
777
778 (let ((s1 "hello, %s")
779 (s2 "world"))
780 (put-text-property 0 (length s1) 'face 'bold s1)
781 (put-text-property 0 (length s2) 'face 'italic s2)
b246b1f6 782 (format s1 s2))
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783
784results in a bold-face string with an italic `world' at the end.
785
786+++
787** Messages can now be displayed with text properties.
788
789Text properties are handled as described above for function `format'.
790The following example displays a bold-face message with an italic
791argument in it.
792
793 (let ((msg "hello, %s!")
794 (arg "world"))
795 (put-text-property 0 (length msg) 'face 'bold msg)
796 (put-text-property 0 (length arg) 'face 'italic arg)
797 (message msg arg))
798
799+++
800** Sound support
801
802Emacs supports playing sound files on GNU/Linux and the free BSDs
803(Voxware driver and native BSD driver, aka as Luigi's driver).
804
805Currently supported file formats are RIFF-WAVE (*.wav) and Sun Audio
806(*.au). You must configure Emacs with the option `--with-sound=yes'
807to enable sound support.
808
809Sound files can be played by calling (play-sound SOUND). SOUND is a
810list of the form `(sound PROPERTY...)'. The function is only defined
811when sound support is present for the system on which Emacs runs. The
812functions runs `play-sound-functions' with one argument which is the
813sound to play, before playing the sound.
814
815The following sound properties are supported:
816
817- `:file FILE'
818
819FILE is a file name. If FILE isn't an absolute name, it will be
820searched relative to `data-directory'.
821
822- `:volume VOLUME'
823
824VOLUME must be an integer in the range 0..100 or a float in the range
8250..1. This property is optional.
826
827Other properties are ignored.
828
829** `multimedia' is a new Finder keyword and Custom group.
830\f
831* New Lisp-level Display features in Emacs 21.1
832
833Note that +++ before an item means the Lisp manual has been updated.
834--- means that I have decided it does not need to be in the Lisp manual.
835When you add a new item, please add it without either +++ or ---
836so I will know I still need to look at it -- rms.
837
838** New face implementation.
839
840Emacs faces have been reimplemented from scratch. They don't use XLFD
841font names anymore and face merging now works as expected.
842
843+++
844*** New faces.
845
846Each face can specify the following display attributes:
847
848 1. Font family or fontset alias name.
849
850 2. Relative proportionate width, aka character set width or set
851 width (swidth), e.g. `semi-compressed'.
852
853 3. Font height in 1/10pt
854
855 4. Font weight, e.g. `bold'.
856
857 5. Font slant, e.g. `italic'.
858
859 6. Foreground color.
860
861 7. Background color.
862
863 8. Whether or not characters should be underlined, and in what color.
864
865 9. Whether or not characters should be displayed in inverse video.
866
867 10. A background stipple, a bitmap.
868
869 11. Whether or not characters should be overlined, and in what color.
870
871 12. Whether or not characters should be strike-through, and in what
872 color.
873
874 13. Whether or not a box should be drawn around characters, its
875 color, the width of the box lines, and 3D appearance.
876
877Faces are frame-local by nature because Emacs allows to define the
878same named face (face names are symbols) differently for different
879frames. Each frame has an alist of face definitions for all named
880faces. The value of a named face in such an alist is a Lisp vector
881with the symbol `face' in slot 0, and a slot for each each of the face
882attributes mentioned above.
883
884There is also a global face alist `face-new-frame-defaults'. Face
885definitions from this list are used to initialize faces of newly
886created frames.
887
888A face doesn't have to specify all attributes. Those not specified
889have a nil value. Faces specifying all attributes are called
890`fully-specified'.
891
892+++
893*** Face merging.
894
895The display style of a given character in the text is determined by
896combining several faces. This process is called `face merging'. Any
897aspect of the display style that isn't specified by overlays or text
898properties is taken from the `default' face. Since it is made sure
899that the default face is always fully-specified, face merging always
900results in a fully-specified face.
901
902+++
903*** Face realization.
904
905After all face attributes for a character have been determined by
906merging faces of that character, that face is `realized'. The
907realization process maps face attributes to what is physically
908available on the system where Emacs runs. The result is a `realized
909face' in form of an internal structure which is stored in the face
910cache of the frame on which it was realized.
911
912Face realization is done in the context of the charset of the
913character to display because different fonts and encodings are used
914for different charsets. In other words, for characters of different
915charsets, different realized faces are needed to display them.
916
917Except for composite characters, faces are always realized for a
918specific character set and contain a specific font, even if the face
919being realized specifies a fontset. The reason is that the result of
920the new font selection stage is better than what can be done with
921statically defined font name patterns in fontsets.
922
923In unibyte text, Emacs' charsets aren't applicable; function
924`char-charset' reports ASCII for all characters, including those >
9250x7f. The X registry and encoding of fonts to use is determined from
926the variable `face-default-registry' in this case. The variable is
927initialized at Emacs startup time from the font the user specified for
928Emacs.
929
930Currently all unibyte text, i.e. all buffers with
931`enable-multibyte-characters' nil are displayed with fonts of the same
932registry and encoding `face-default-registry'. This is consistent
933with the fact that languages can also be set globally, only.
934
935++++
936**** Clearing face caches.
937
938The Lisp function `clear-face-cache' can be called to clear face caches
939on all frames. If called with a non-nil argument, it will also unload
940unused fonts.
941
942+++
943*** Font selection.
944
945Font selection tries to find the best available matching font for a
946given (charset, face) combination. This is done slightly differently
947for faces specifying a fontset, or a font family name.
948
949If the face specifies a fontset name, that fontset determines a
950pattern for fonts of the given charset. If the face specifies a font
951family, a font pattern is constructed. Charset symbols have a
952property `x-charset-registry' for that purpose that maps a charset to
953an XLFD registry and encoding in the font pattern constructed.
954
955Available fonts on the system on which Emacs runs are then matched
956against the font pattern. The result of font selection is the best
957match for the given face attributes in this font list.
958
959Font selection can be influenced by the user.
960
961The user can specify the relative importance he gives the face
962attributes width, height, weight, and slant by setting
963face-font-selection-order (faces.el) to a list of face attribute
964names. The default is (:width :height :weight :slant), and means
965that font selection first tries to find a good match for the font
966width specified by a face, then---within fonts with that width---tries
967to find a best match for the specified font height, etc.
968
969Setting `face-alternative-font-family-alist' allows the user to
970specify alternative font families to try if a family specified by a
971face doesn't exist.
972
973+++
974**** Scalable fonts
975
976Emacs can make use of scalable fonts but doesn't do so by default,
977since the use of too many or too big scalable fonts may crash XFree86
978servers.
979
980To enable scalable font use, set the variable
b246b1f6 981`scalable-fonts-allowed'. A value of nil, the default, means never use
a933dad1
DL
982scalable fonts. A value of t means any scalable font may be used.
983Otherwise, the value must be a list of regular expressions. A
984scalable font may then be used if it matches a regular expression from
985that list. Example:
986
987 (setq scalable-fonts-allowed '("muleindian-2$"))
988
989allows the use of scalable fonts with registry `muleindian-2'.
990
991+++
992*** Functions and variables related to font selection.
993
994- Function: x-family-fonts &optional FAMILY FRAME
995
996Return a list of available fonts of family FAMILY on FRAME. If FAMILY
997is omitted or nil, list all families. Otherwise, FAMILY must be a
998string, possibly containing wildcards `?' and `*'.
999
1000If FRAME is omitted or nil, use the selected frame. Each element of
1001the result is a vector [FAMILY WIDTH POINT-SIZE WEIGHT SLANT FIXED-P
1002FULL REGISTRY-AND-ENCODING]. FAMILY is the font family name.
1003POINT-SIZE is the size of the font in 1/10 pt. WIDTH, WEIGHT, and
1004SLANT are symbols describing the width, weight and slant of the font.
1005These symbols are the same as for face attributes. FIXED-P is non-nil
1006if the font is fixed-pitch. FULL is the full name of the font, and
1007REGISTRY-AND-ENCODING is a string giving the registry and encoding of
1008the font. The result list is sorted according to the current setting
1009of the face font sort order.
1010
1011- Function: x-font-family-list
1012
1013Return a list of available font families on FRAME. If FRAME is
1014omitted or nil, use the selected frame. Value is a list of conses
1015(FAMILY . FIXED-P) where FAMILY is a font family, and FIXED-P is
1016non-nil if fonts of that family are fixed-pitch.
1017
1018- Variable: font-list-limit
1019
1020Limit for font matching. If an integer > 0, font matching functions
1021won't load more than that number of fonts when searching for a
1022matching font. The default is currently 100.
1023
1024+++
1025*** Setting face attributes.
1026
1027For the most part, the new face implementation is interface-compatible
1028with the old one. Old face attribute related functions are now
1029implemented in terms of the new functions `set-face-attribute' and
1030`face-attribute'.
1031
1032Face attributes are identified by their names which are keyword
1033symbols. All attributes can be set to `unspecified'.
1034
1035The following attributes are recognized:
1036
1037`:family'
1038
1039VALUE must be a string specifying the font family, e.g. ``courier'',
1040or a fontset alias name. If a font family is specified, wild-cards `*'
1041and `?' are allowed.
1042
1043`:width'
1044
1045VALUE specifies the relative proportionate width of the font to use.
1046It must be one of the symbols `ultra-condensed', `extra-condensed',
1047`condensed', `semi-condensed', `normal', `semi-expanded', `expanded',
1048`extra-expanded', or `ultra-expanded'.
1049
1050`:height'
1051
1052VALUE must be an integer specifying the height of the font to use in
10531/10 pt.
1054
1055`:weight'
1056
1057VALUE specifies the weight of the font to use. It must be one of the
1058symbols `ultra-bold', `extra-bold', `bold', `semi-bold', `normal',
1059`semi-light', `light', `extra-light', `ultra-light'.
1060
1061`:slant'
1062
1063VALUE specifies the slant of the font to use. It must be one of the
1064symbols `italic', `oblique', `normal', `reverse-italic', or
1065`reverse-oblique'.
1066
1067`:foreground', `:background'
1068
1069VALUE must be a color name, a string.
1070
1071`:underline'
1072
1073VALUE specifies whether characters in FACE should be underlined. If
1074VALUE is t, underline with foreground color of the face. If VALUE is
1075a string, underline with that color. If VALUE is nil, explicitly
1076don't underline.
1077
1078`:overline'
1079
1080VALUE specifies whether characters in FACE should be overlined. If
1081VALUE is t, overline with foreground color of the face. If VALUE is a
1082string, overline with that color. If VALUE is nil, explicitly don't
1083overline.
1084
1085`:strike-through'
1086
1087VALUE specifies whether characters in FACE should be drawn with a line
1088striking through them. If VALUE is t, use the foreground color of the
1089face. If VALUE is a string, strike-through with that color. If VALUE
1090is nil, explicitly don't strike through.
1091
1092`:box'
1093
1094VALUE specifies whether characters in FACE should have a box drawn
1095around them. If VALUE is nil, explicitly don't draw boxes. If
1096VALUE is t, draw a box with lines of width 1 in the foreground color
1097of the face. If VALUE is a string, the string must be a color name,
1098and the box is drawn in that color with a line width of 1. Otherwise,
1099VALUE must be a property list of the form `(:line-width WIDTH
1100:color COLOR :style STYLE)'. If a keyword/value pair is missing from
1101the property list, a default value will be used for the value, as
1102specified below. WIDTH specifies the width of the lines to draw; it
1103defaults to 1. COLOR is the name of the color to draw in, default is
1104the foreground color of the face for simple boxes, and the background
1105color of the face for 3D boxes. STYLE specifies whether a 3D box
1106should be draw. If STYLE is `released-button', draw a box looking
1107like a released 3D button. If STYLE is `pressed-button' draw a box
1108that appears like a pressed button. If STYLE is nil, the default if
1109the property list doesn't contain a style specification, draw a 2D
1110box.
1111
1112`:inverse-video'
1113
1114VALUE specifies whether characters in FACE should be displayed in
1115inverse video. VALUE must be one of t or nil.
1116
1117`:stipple'
1118
1119If VALUE is a string, it must be the name of a file of pixmap data.
1120The directories listed in the `x-bitmap-file-path' variable are
1121searched. Alternatively, VALUE may be a list of the form (WIDTH
1122HEIGHT DATA) where WIDTH and HEIGHT are the size in pixels, and DATA
1123is a string containing the raw bits of the bitmap. VALUE nil means
1124explicitly don't use a stipple pattern.
1125
1126For convenience, attributes `:family', `:width', `:height', `:weight',
1127and `:slant' may also be set in one step from an X font name:
1128
1129`:font'
1130
1131Set font-related face attributes from VALUE. VALUE must be a valid
1132XLFD font name. If it is a font name pattern, the first matching font
1133is used--this is for compatibility with the behavior of previous
1134versions of Emacs.
1135
1136For compatibility with Emacs 20, keywords `:bold' and `:italic' can
1137be used to specify that a bold or italic font should be used. VALUE
1138must be t or nil in that case. A value of `unspecified' is not allowed."
1139
1140Please see also the documentation of `set-face-attribute' and
1141`defface'.
1142
1143*** Face attributes and X resources
1144
1145The following X resource names can be used to set face attributes
1146from X resources:
1147
1148 Face attribute X resource class
1149-----------------------------------------------------------------------
1150 :family attributeFamily . Face.AttributeFamily
1151 :width attributeWidth Face.AttributeWidth
1152 :height attributeHeight Face.AttributeHeight
1153 :weight attributeWeight Face.AttributeWeight
1154 :slant attributeSlant Face.AttributeSlant
1155 foreground attributeForeground Face.AttributeForeground
1156 :background attributeBackground . Face.AttributeBackground
1157 :overline attributeOverline Face.AttributeOverline
1158 :strike-through attributeStrikeThrough Face.AttributeStrikeThrough
1159 :box attributeBox Face.AttributeBox
1160 :underline attributeUnderline Face.AttributeUnderline
1161 :inverse-video attributeInverse Face.AttributeInverse
1162 :stipple attributeStipple Face.AttributeStipple
1163 or attributeBackgroundPixmap
1164 Face.AttributeBackgroundPixmap
1165 :font attributeFont Face.AttributeFont
1166 :bold attributeBold Face.AttributeBold
1167 :italic attributeItalic . Face.AttributeItalic
1168 :font attributeFont Face.AttributeFont
1169
1170+++
1171*** Text property `face'.
1172
1173The value of the `face' text property can now be a single face
1174specification or a list of such specifications. Each face
1175specification can be
1176
11771. A symbol or string naming a Lisp face.
1178
11792. A property list of the form (KEYWORD VALUE ...) where each
1180 KEYWORD is a face attribute name, and VALUE is an appropriate value
1181 for that attribute. Please see the doc string of `set-face-attribute'
1182 for face attribute names.
1183
11843. Conses of the form (FOREGROUND-COLOR . COLOR) or
1185 (BACKGROUND-COLOR . COLOR) where COLOR is a color name. This is
1186 for compatibility with previous Emacs versions.
1187
1188+++
1189** Support functions for colors on text-only terminals.
1190
1191The function `face-register-tty-color' can be used to define colors
1192for use on TTY frames. It maps a color name to a color number on the
1193terminal. Emacs defines a couple of default color mappings by
1194default. You can get defined colors with a call to
1195`tty-defined-colors'. The function `face-clear-tty-colors' can be
1196used to clear the mapping table.
1197
1198+++
1199** The minibuffer prompt is now actually inserted in the minibuffer.
a933dad1 1200
463cac2d 1201This makes it possible to scroll through the prompt, if you want to.
a933dad1
DL
1202
1203The function minubuffer-prompt-end returns the current position of the
1204end of the minibuffer prompt, if the minibuffer is current.
1205Otherwise, it returns zero.
1206
463cac2d
GM
1207** New `field' abstraction in buffers.
1208
1209There is now code to support an abstraction called `fields' in emacs
1210buffers. A field is a contiguous region of text with the same `field'
1211text-property.
1212
1213Certain functions, such as forward-word, forward-sentence,
1214forward-paragraph, beginning-of-line, etc., stop moving when they come
1215to the boundary between fields (beginning-of-line and end-of-line will
1216not let the point move past the field boundary, but other movement
1217commands continue into the next field if repeated).
1218
1219The new function constrain-to-field may be used to achieve similar
1220behavior; other new field functions include field-beginning, field-end,
1221erase-field, and field-string.
1222
1223Now that the minibuffer prompt is inserted into the minibuffer, it is in
1224a separate field from the user-input part of the buffer, so that many
1225editing commands treat the user's text separately from the prompt.
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1226
1227+++
1228** Image support.
1229
1230Emacs can now display images. Images are inserted into text by giving
1231strings or buffer text a `display' text property containing one of
1232(AREA IMAGE) or IMAGE. The display of the `display' property value
1233replaces the display of the characters having that property.
1234
1235If the property value has the form (AREA IMAGE), AREA must be one of
1236`(margin left-margin)', `(margin right-margin)' or `(margin nil)'. If
1237AREA is `(margin nil)', IMAGE will be displayed in the text area of a
1238window, otherwise it will be displayed in the left or right marginal
1239area.
1240
1241IMAGE is an image specification.
1242
1243*** Image specifications
1244
1245Image specifications are lists of the form `(image PROPS)' where PROPS
1246is a property list whose keys are keyword symbols. Each
1247specifications must contain a property `:type TYPE' with TYPE being a
1248symbol specifying the image type, e.g. `xbm'.
1249
1250The following is a list of properties all image types share.
1251
1252`:ascent ASCENT'
1253
1254ASCENT must be a number in the range 0..100, and specifies the percentage
1255of the image's height to use for its ascent. Default is 50.
1256
1257`:margin MARGIN'
1258
1259MARGIN must be a number >= 0 specifying how many pixels to put as
1260margin around the image. Default is 0.
1261
1262`:relief RELIEF'
1263
1264RELIEF is analogous to the `:relief' attribute of faces. Puts a relief
1265around an image.
1266
1267`:algorithm ALGO'
1268
1269Apply an image algorithm to the image before displaying it. ALGO must
1270be a symbol specifying the algorithm. Currently only `laplace' is
1271supported which applies a Laplace edge detection algorithm to an image
1272which is intended to display images "disabled."
1273
1274`:heuristic-mask BG'
1275
1276If BG is not nil, build a clipping mask for the image, so that the
1277background of a frame is visible behind the image. If BG is t,
1278determine the background color of the image by looking at the 4
1279corners of the image, assuming the most frequently occuring color from
1280the corners is the background color of the image. Otherwise, BG must
1281be a list `(RED GREEN BLUE)' specifying the color to assume for the
1282background of the image.
1283
1284`:file FILE'
1285
1286Load image from FILE. If FILE is not absolute after expanding it,
1287search for the image in `data-directory'. Some image types support
1288building images from data. When this is done, no `:file' property
1289may be present in the image specification.
1290
1291
1292*** Supported image types
1293
b246b1f6 1294**** XBM, image type `xbm'.
a933dad1
DL
1295
1296XBM images don't require an external library. Additional image
1297properties supported are
1298
1299`:foreground FG'
1300
1301FG must be a string specifying the image foreground color. Default
1302is the frame's foreground.
1303
1304`:background FG'
1305
1306BG must be a string specifying the image foreground color. Default is
1307the frame's background color.
1308
1309XBM images can be constructed from data instead of file. In this
1310case, the image specification must contain the following properties
1311instead of a `:file' property.
1312
1313`:width WIDTH'
1314
1315WIDTH specifies the width of the image in pixels.
1316
1317`:height HEIGHT'
1318
1319HEIGHT specifies the height of the image in pixels.
1320
1321`:data DATA'
1322
1323DATA must be either
1324
1325 1. a string large enough to hold the bitmap data, i.e. it must
1326 have a size >= (WIDTH + 7) / 8 * HEIGHT
1327
1328 2. a bool-vector of size >= WIDTH * HEIGHT
1329
1330 3. a vector of strings or bool-vectors, one for each line of the
1331 bitmap.
1332
1333**** XPM, image type `xpm'
1334
1335XPM images require the external library `libXpm', package
1336`xpm-3.4k.tar.gz', version 3.4k or later. Make sure the library is
1337found when Emacs is configured by supplying appropriate paths via
1338`--x-includes' and `--x-libraries'.
1339
1340Additional image properties supported are:
1341
1342`:color-symbols SYMBOLS'
1343
1344SYMBOLS must be a list of pairs (NAME . COLOR), with NAME being the
1345name of color as it appears in an XPM file, and COLOR being an X color
1346name.
1347
1348XPM images can be built from memory instead of files. In that case,
1349add a `:data' property instead of a `:file' property.
1350
1351`:data DATA'
1352
1353DATA must be a string containing an XPM image. The contents of the
1354string are of the same format as that of XPM files.
1355
1356The XPM library uses libz in its implementation so that it is able
1357to display compressed images.
1358
1359**** PBM, image type `pbm'
1360
1361PBM images don't require an external library. Color, gray-scale and
1362mono images are supported. There are no additional image properties
1363defined.
1364
1365**** JPEG, image type `jpeg'
1366
1367Support for JPEG images requires the external library `libjpeg',
1368package `jpegsrc.v6a.tar.gz', or later. There are no additional image
1369properties defined.
1370
1371**** TIFF, image type `tiff'
1372
1373Support for TIFF images requires the external library `libtiff',
1374package `tiff-v3.4-tar.gz', or later. There are no additional image
1375properties defined.
1376
1377**** GIF, image type `gif'
1378
1379Support for GIF images requires the external library `libungif', package
1380`libungif-4.1.0', or later.
1381
1382Additional image properties supported are:
1383
1384`:index INDEX'
1385
1386INDEX must be an integer >= 0. Load image number INDEX from a
1387multi-image GIF file. An error is signalled if INDEX is too large.
1388
1389This could be used to implement limited support for animated GIFs.
1390For example, the following function displays a multi-image GIF file
1391at point-min in the current buffer, switching between sub-images
1392every 0.1 seconds.
1393
1394(defun show-anim (file max)
1395 "Display multi-image GIF file FILE which contains MAX subimages."
1396 (display-anim (current-buffer) file 0 max t))
1397
1398(defun display-anim (buffer file idx max first-time)
1399 (when (= idx max)
1400 (setq idx 0))
1401 (let ((img (create-image file nil :index idx)))
1402 (save-excursion
1403 (set-buffer buffer)
1404 (goto-char (point-min))
1405 (unless first-time (delete-char 1))
1406 (insert-image img "x"))
1407 (run-with-timer 0.1 nil 'display-anim buffer file (1+ idx) max nil)))
1408
1409**** PNG, image type `png'
1410
1411Support for PNG images requires the external library `libpng',
1412package `libpng-1.0.2.tar.gz', or later. There are no additional image
1413properties defined.
1414
1415**** Ghostscript, image type `postscript'.
1416
1417Additional image properties supported are:
1418
1419`:pt-width WIDTH'
1420
1421WIDTH is width of the image in pt (1/72 inch). WIDTH must be an
b246b1f6 1422integer. This is a required property.
a933dad1
DL
1423
1424`:pt-height HEIGHT'
1425
1426HEIGHT specifies the height of the image in pt (1/72 inch). HEIGHT
b246b1f6 1427must be a integer. This is an required property.
a933dad1
DL
1428
1429`:bounding-box BOX'
1430
1431BOX must be a list or vector of 4 integers giving the bounding box of
1432the PS image, analogous to the `BoundingBox' comment found in PS
1433files. This is an required property.
1434
1435Part of the Ghostscript interface is implemented in Lisp. See
1436lisp/gs.el.
1437
1438*** Lisp interface.
1439
1440The variable `image-types' contains a list of those image types
1441which are supported in the current configuration.
1442
1443Images are stored in an image cache and removed from the cache when
1444they haven't been displayed for `image-cache-eviction-delay seconds.
1445The function `clear-image-cache' can be used to clear the image cache
1446manually.
1447
1448*** Simplified image API, image.el
1449
1450The new Lisp package image.el contains functions that simplify image
1451creation and putting images into text. The function `create-image'
1452can be used to create images. The macro `defimage' can be used to
1453define an image based on available image types. The functions
1454`put-image' and `insert-image' can be used to insert an image into a
1455buffer.
1456
1457+++
1458** Display margins.
1459
1460Windows can now have margins which are used for special text
1461and images.
1462
1463To give a window margins, either set the buffer-local variables
1464`left-margin-width' and `right-margin-width', or call
1465`set-window-margins'. The function `window-margins' can be used to
1466obtain the current settings. To make `left-margin-width' and
1467`right-margin-width' take effect, you must set them before displaying
1468the buffer in a window, or use `set-window-buffer' to force an update
1469of the display margins.
1470
1471You can put text in margins by giving it a `display' text property
1472containing a pair of the form `(LOCATION . VALUE)', where LOCATION is
1473one of `left-margin' or `right-margin' or nil. VALUE can be either a
1474string, an image specification or a stretch specification (see later
1475in this file).
1476
1477+++
1478** Help display
1479
1480Emacs displays short help messages in the echo area, when the mouse
1481moves over a tool-bar item or a piece of text that has a text property
1482`help-echo'. This feature also applies to strings in the mode line
1483that have a `help-echo' property.
1484
1485The value of the `help-echo' property must be a string. For tool-bar
1486items, their key definition is used to determine the help to display.
1487If their definition contains a property `:help FORM', FORM is
1488evaluated to determine the help string. Otherwise, the caption of the
1489tool-bar item is used.
1490
1491The hook `show-help-function' can be set to a function that displays
1492help differently. For example, enabling a tooltip window causes the
1493help display to appear there instead of in the echo area.
1494
1495+++
1496** Vertical fractional scrolling.
1497
1498The display of text in windows can be scrolled smoothly in pixels.
1499This is useful, for example, for making parts of large images visible.
1500
1501The function `window-vscroll' returns the current value of vertical
1502scrolling, a non-negative fraction of the canonical character height.
1503The function `set-window-vscroll' can be used to set the vertical
1504scrolling value. Here is an example of how these function might be
1505used.
1506
1507 (global-set-key [A-down]
1508 #'(lambda ()
1509 (interactive)
1510 (set-window-vscroll (selected-window)
1511 (+ 0.5 (window-vscroll)))))
1512 (global-set-key [A-up]
1513 #'(lambda ()
1514 (interactive)
1515 (set-window-vscroll (selected-window)
1516 (- (window-vscroll) 0.5)))))
1517
1518+++
1519** New hook `fontification-functions'.
1520
1521Functions from `fontification-functions' are called from redisplay
1522when it encounters a region of text that is not yet fontified. This
1523variable automatically becomes buffer-local when set. Each function
1524is called with one argument, POS.
1525
1526At least one of the hook functions should fontify one or more
1527characters starting at POS in the current buffer. It should mark them
1528as fontified by giving them a non-nil value of the `fontified' text
1529property. It may be reasonable for these functions to check for the
1530`fontified' property and not put it back on, but they do not have to.
1531
1532+++
1533** Tool bar support.
1534
1535Emacs supports a tool bar at the top of a frame under X. The frame
1536parameter `tool-bar-lines' (X resource "toolBar", class "ToolBar")
1537controls how may lines to reserve for the tool bar. A zero value
1538suppresses the tool bar. If the value is non-zero and
1539`auto-resize-tool-bars' is non-nil the tool bar's size will be changed
1540automatically so that all tool bar items are visible.
1541
1542*** Tool bar item definitions
1543
1544Tool bar items are defined using `define-key' with a prefix-key
1545`tool-bar'. For example `(define-key global-map [tool-bar item1] ITEM)'
1546where ITEM is a list `(menu-item CAPTION BINDING PROPS...)'.
1547
1548CAPTION is the caption of the item, If it's not a string, it is
1549evaluated to get a string. The caption is currently not displayed in
1550the tool bar, but it is displayed if the item doesn't have a `:help'
1551property (see below).
1552
1553BINDING is the tool bar item's binding. Tool bar items with keymaps as
1554binding are currently ignored.
1555
1556The following properties are recognized:
1557
1558`:enable FORM'.
1559
1560FORM is evaluated and specifies whether the tool bar item is enabled
1561or disabled.
1562
1563`:visible FORM'
1564
1565FORM is evaluated and specifies whether the tool bar item is displayed.
1566
1567`:filter FUNCTION'
1568
1569FUNCTION is called with one parameter, the same list BINDING in which
1570FUNCTION is specified as the filter. The value FUNCTION returns is
1571used instead of BINDING to display this item.
1572
1573`:button (TYPE SELECTED)'
1574
1575TYPE must be one of `:radio' or `:toggle'. SELECTED is evaluated
1576and specifies whether the button is selected (pressed) or not.
1577
1578`:image IMAGES'
1579
1580IMAGES is either a single image specification or a vector of four
1581image specifications. If it is a vector, this table lists the
1582meaning of each of the four elements:
1583
1584 Index Use when item is
1585 ----------------------------------------
1586 0 enabled and selected
1587 1 enabled and deselected
1588 2 disabled and selected
1589 3 disabled and deselected
1590
1591`:help HELP-STRING'.
1592
1593Gives a help string to display for the tool bar item. This help
1594is displayed when the mouse is moved over the item.
1595
1596*** Tool-bar-related variables.
1597
1598If `auto-resize-tool-bar' is non-nil, the tool bar will automatically
1599resize to show all defined tool bar items. It will never grow larger
1600than 1/4 of the frame's size.
1601
1602If `auto-raise-tool-bar-buttons' is non-nil, tool bar buttons will be
1603raised when the mouse moves over them.
1604
1605You can add extra space between tool bar items by setting
1606`tool-bar-button-margin' to a positive integer specifying a number of
1607pixels. Default is 1.
1608
1609You can change the shadow thickness of tool bar buttons by setting
1610`tool-bar-button-relief' to an integer. Default is 3.
1611
1612*** Tool-bar clicks with modifiers.
1613
1614You can bind commands to clicks with control, shift, meta etc. on
1615a tool bar item. If
1616
1617 (define-key global-map [tool-bar shell]
1618 '(menu-item "Shell" shell
1619 :image (image :type xpm :file "shell.xpm")))
1620
1621is the original tool bar item definition, then
1622
1623 (define-key global-map [tool-bar S-shell] 'some-command)
1624
1625makes a binding to run `some-command' for a shifted click on the same
1626item.
1627
1628** Mode line changes.
1629
1630+++
1631*** Mouse-sensitive mode line.
1632
1633The mode line can be made mouse-sensitive by displaying strings there
1634that have a `local-map' text property. There are three ways to display
1635a string with a `local-map' property in the mode line.
1636
16371. The mode line spec contains a variable whose string value has
1638a `local-map' text property.
1639
16402. The mode line spec contains a format specifier (e.g. `%12b'), and
1641that format specifier has a `local-map' property.
1642
16433. The mode line spec contains a list containing `:eval FORM'. FORM
1644is evaluated. If the result is a string, and that string has a
1645`local-map' property.
1646
1647The same mechanism is used to determine the `face' and `help-echo'
1648properties of strings in the mode line. See `bindings.el' for an
1649example.
1650
1651+++
1652*** You can suppress mode-line display by setting the buffer-local
1653variable mode-line-format to nil.
1654
1655+++
1656*** A headerline can now be displayed at the top of a window.
1657
1658This mode line's contents are controlled by the new variable
1659`header-line-format' and `default-header-line-format' which are
1660completely analogous to `mode-line-format' and
1661`default-mode-line-format'. A value of nil means don't display a top
1662line.
1663
1664The appearance of top mode lines is controlled by the face
1665`header-line'.
1666
1667The function `coordinates-in-window-p' returns `header-line' for a
1668position in the header-line.
1669
1670+++
1671** Text property `display'
1672
1673The `display' text property is used to insert images into text, and
1674also control other aspects of how text displays. The value of the
1675`display' property should be a display specification, as described
1676below, or a list or vector containing display specifications.
1677
1678*** Variable width and height spaces
1679
1680To display a space of fractional width or height, use a display
1681specification of the form `(LOCATION STRECH)'. If LOCATION is
1682`(margin left-margin)', the space is displayed in the left marginal
1683area, if it is `(margin right-margin)', it is displayed in the right
1684marginal area, and if LOCATION is `(margin nil)' the space is
1685displayed in the text. In the latter case you can also use the
1686simpler form STRETCH as property value.
1687
1688The stretch specification STRETCH itself is a list of the form `(space
1689PROPS)', where PROPS is a property list which can contain the
1690properties described below.
1691
1692The display of the fractional space replaces the display of the
1693characters having the `display' property.
1694
1695- :width WIDTH
1696
1697Specifies that the space width should be WIDTH times the normal
1698character width. WIDTH can be an integer or floating point number.
1699
1700- :relative-width FACTOR
1701
1702Specifies that the width of the stretch should be computed from the
1703first character in a group of consecutive characters that have the
1704same `display' property. The computation is done by multiplying the
1705width of that character by FACTOR.
1706
1707- :align-to HPOS
1708
1709Specifies that the space should be wide enough to reach HPOS. The
1710value HPOS is measured in units of the normal character width.
1711
1712Exactly one of the above properties should be used.
1713
1714- :height HEIGHT
1715
1716Specifies the height of the space, as HEIGHT, measured in terms of the
1717normal line height.
1718
1719- :relative-height FACTOR
1720
1721The height of the space is computed as the product of the height
1722of the text having the `display' property and FACTOR.
1723
1724- :ascent ASCENT
1725
1726Specifies that ASCENT percent of the height of the stretch should be
1727used for the ascent of the stretch, i.e. for the part above the
1728baseline. The value of ASCENT must be a non-negative number less or
1729equal to 100.
1730
1731You should not use both `:height' and `:relative-height' together.
1732
1733*** Images
1734
1735A display specification for an image has the form `(LOCATION
1736. IMAGE)', where IMAGE is an image specification. The image replaces,
1737in the display, the characters having this display specification in
1738their `display' text property. If LOCATION is `(margin left-margin)',
1739the image will be displayed in the left marginal area, if it is
1740`(margin right-margin)' it will be displayed in the right marginal
1741area, and if LOCATION is `(margin nil)' the image will be displayed in
1742the text. In the latter case you can also use the simpler form IMAGE
1743as display specification.
1744
1745*** Other display properties
1746
1747- :space-width FACTOR
1748
1749Specifies that space characters in the text having that property
1750should be displayed FACTOR times as wide as normal; FACTOR must be an
1751integer or float.
1752
1753- :height HEIGHT
1754
1755Display text having this property in a font that is smaller or larger.
1756
1757If HEIGHT is a list of the form `(+ N)', where N is an integer, that
1758means to use a font that is N steps larger. If HEIGHT is a list of
1759the form `(- N)', that means to use a font that is N steps smaller. A
1760``step'' is defined by the set of available fonts; each size for which
1761a font is available counts as a step.
1762
1763If HEIGHT is a number, that means to use a font that is HEIGHT times
1764as tall as the frame's default font.
1765
1766If HEIGHT is a symbol, it is called as a function with the current
1767height as argument. The function should return the new height to use.
1768
1769Otherwise, HEIGHT is evaluated to get the new height, with the symbol
1770`height' bound to the current specified font height.
1771
1772- :raise FACTOR
1773
1774FACTOR must be a number, specifying a multiple of the current
1775font's height. If it is positive, that means to display the characters
1776raised. If it is negative, that means to display them lower down. The
1777amount of raising or lowering is computed without taking account of the
1778`:height' subproperty.
1779
1780*** Conditional display properties
1781
1782All display specifications can be conditionalized. If a specification
1783has the form `(:when CONDITION . SPEC)', the specification SPEC
1784applies only when CONDITION yields a non-nil value when evaluated.
1785During evaluattion, point is temporarily set to the end position of
1786the text having the `display' property.
1787
1788The normal specification consisting of SPEC only is equivalent to
1789`(:when t SPEC)'.
1790
1791+++
1792** New menu separator types.
1793
1794Emacs now supports more than one menu separator type. Menu items with
1795item names consisting of dashes only (including zero dashes) are
1796treated like before. In addition, the following item names are used
1797to specify other menu separator types.
1798
1799- `--no-line' or `--space', or `--:space', or `--:noLine'
1800
1801No separator lines are drawn, but a small space is inserted where the
1802separator occurs.
1803
1804- `--single-line' or `--:singleLine'
1805
1806A single line in the menu's foreground color.
1807
1808- `--double-line' or `--:doubleLine'
1809
1810A double line in the menu's foreground color.
1811
1812- `--single-dashed-line' or `--:singleDashedLine'
1813
1814A single dashed line in the menu's foreground color.
1815
1816- `--double-dashed-line' or `--:doubleDashedLine'
1817
1818A double dashed line in the menu's foreground color.
1819
1820- `--shadow-etched-in' or `--:shadowEtchedIn'
1821
1822A single line with 3D sunken appearance. This is the the form
1823displayed for item names consisting of dashes only.
1824
1825- `--shadow-etched-out' or `--:shadowEtchedOut'
1826
1827A single line with 3D raised appearance.
1828
1829- `--shadow-etched-in-dash' or `--:shadowEtchedInDash'
1830
1831A single dashed line with 3D sunken appearance.
1832
1833- `--shadow-etched-out-dash' or `--:shadowEtchedOutDash'
1834
1835A single dashed line with 3D raise appearance.
1836
1837- `--shadow-double-etched-in' or `--:shadowDoubleEtchedIn'
1838
1839Two lines with 3D sunken appearance.
1840
1841- `--shadow-double-etched-out' or `--:shadowDoubleEtchedOut'
1842
1843Two lines with 3D raised appearance.
1844
1845- `--shadow-double-etched-in-dash' or `--:shadowDoubleEtchedInDash'
1846
1847Two dashed lines with 3D sunken appearance.
1848
1849- `--shadow-double-etched-out-dash' or `--:shadowDoubleEtchedOutDash'
1850
1851Two dashed lines with 3D raised appearance.
1852
1853Under LessTif/Motif, the last four separator types are displayed like
1854the corresponding single-line separators.
1855
1856+++
1857** New frame parameters for scroll bar colors.
1858
1859The new frame parameters `scroll-bar-foreground' and
1860`scroll-bar-background' can be used to change scroll bar colors.
1861Their value must be either a color name, a string, or nil to specify
1862that scroll bars should use a default color. For toolkit scroll bars,
1863default colors are toolkit specific. For non-toolkit scroll bars, the
1864default background is the background color of the frame, and the
1865default foreground is black.
1866
1867The X resource name of these parameters are `scrollBarForeground'
1868(class ScrollBarForeground) and `scrollBarBackground' (class
1869`ScrollBarBackground').
1870
1871Setting these parameters overrides toolkit specific X resource
1872settings for scroll bar colors.
1873
1874+++
1875** You can set `redisplay-dont-pause' to a non-nil value to prevent
1876display updates from being interrupted when input is pending.
1877
1878---
1879** Changing a window's width may now change its window start if it
1880starts on a continuation line. The new window start is computed based
1881on the window's new width, starting from the start of the continued
1882line as the start of the screen line with the minimum distance from
1883the original window start.
1884
1885---
1886** The variable `hscroll-step' and the functions
1887`hscroll-point-visible' and `hscroll-window-column' have been removed
1888now that proper horizontal scrolling is implemented.
1889
1890+++
1891** Windows can now be made fixed-width and/or fixed-height.
1892
1893A window is fixed-size if its buffer has a buffer-local variable
1894`window-size-fixed' whose value is not nil. A value of `height' makes
1895windows fixed-height, a value of `width' makes them fixed-width, any
1896other non-nil value makes them both fixed-width and fixed-height.
1897
1898The following code makes all windows displaying the current buffer
1899fixed-width and fixed-height.
1900
1901 (set (make-local-variable 'window-size-fixed) t)
1902
1903A call to enlarge-window on a window gives an error if that window is
1904fixed-width and it is tried to change the window's width, or if the
1905window is fixed-height, and it is tried to change its height. To
1906change the size of a fixed-size window, bind `window-size-fixed'
1907temporarily to nil, for example
1908
1909 (let ((window-size-fixed nil))
1910 (enlarge-window 10))
1911
1912Likewise, an attempt to split a fixed-height window vertically,
1913or a fixed-width window horizontally results in a error.
1914\f
1915* Changes in Emacs 20.4
1916
1917** Init file may be called .emacs.el.
1918
1919You can now call the Emacs init file `.emacs.el'.
1920Formerly the name had to be `.emacs'. If you use the name
1921`.emacs.el', you can byte-compile the file in the usual way.
1922
1923If both `.emacs' and `.emacs.el' exist, the latter file
1924is the one that is used.
1925
1926** shell-command, and shell-command-on-region, now return
1927the exit code of the command (unless it is asynchronous).
1928Also, you can specify a place to put the error output,
1929separate from the command's regular output.
1930Interactively, the variable shell-command-default-error-buffer
1931says where to put error output; set it to a buffer name.
1932In calls from Lisp, an optional argument ERROR-BUFFER specifies
1933the buffer name.
1934
1935When you specify a non-nil error buffer (or buffer name), any error
1936output is inserted before point in that buffer, with \f\n to separate
1937it from the previous batch of error output. The error buffer is not
1938cleared, so error output from successive commands accumulates there.
1939
1940** Setting the default value of enable-multibyte-characters to nil in
1941the .emacs file, either explicitly using setq-default, or via Custom,
1942is now essentially equivalent to using --unibyte: all buffers
1943created during startup will be made unibyte after loading .emacs.
1944
1945** C-x C-f now handles the wildcards * and ? in file names. For
1946example, typing C-x C-f c*.c RET visits all the files whose names
1947match c*.c. To visit a file whose name contains * or ?, add the
1948quoting sequence /: to the beginning of the file name.
1949
1950** The M-x commands keep-lines, flush-lines and count-matches
1951now have the same feature as occur and query-replace:
1952if the pattern contains any upper case letters, then
1953they never ignore case.
1954
1955** The end-of-line format conversion feature previously mentioned
1956under `* Emacs 20.1 changes for MS-DOS and MS-Windows' actually
1957applies to all operating systems. Emacs recognizes from the contents
1958of a file what convention it uses to separate lines--newline, CRLF, or
1959just CR--and automatically converts the contents to the normal Emacs
1960convention (using newline to separate lines) for editing. This is a
1961part of the general feature of coding system conversion.
1962
1963If you subsequently save the buffer, Emacs converts the text back to
1964the same format that was used in the file before.
1965
1966You can turn off end-of-line conversion by setting the variable
1967`inhibit-eol-conversion' to non-nil, e.g. with Custom in the MULE group.
1968
1969** The character set property `prefered-coding-system' has been
1970renamed to `preferred-coding-system', for the sake of correct spelling.
1971This is a fairly internal feature, so few programs should be affected.
1972
1973** Mode-line display of end-of-line format is changed.
1974The indication of the end-of-line format of the file visited by a
1975buffer is now more explicit when that format is not the usual one for
1976your operating system. For example, the DOS-style end-of-line format
1977is displayed as "(DOS)" on Unix and GNU/Linux systems. The usual
1978end-of-line format is still displayed as a single character (colon for
1979Unix, backslash for DOS and Windows, and forward slash for the Mac).
1980
1981The values of the variables eol-mnemonic-unix, eol-mnemonic-dos,
1982eol-mnemonic-mac, and eol-mnemonic-undecided, which are strings,
1983control what is displayed in the mode line for each end-of-line
1984format. You can now customize these variables.
1985
1986** In the previous version of Emacs, tar-mode didn't work well if a
1987filename contained non-ASCII characters. Now this is fixed. Such a
1988filename is decoded by file-name-coding-system if the default value of
1989enable-multibyte-characters is non-nil.
1990
1991** The command temp-buffer-resize-mode toggles a minor mode
1992in which temporary buffers (such as help buffers) are given
1993windows just big enough to hold the whole contents.
1994
1995** If you use completion.el, you must now run the function
1996dynamic-completion-mode to enable it. Just loading the file
1997doesn't have any effect.
1998
1999** In Flyspell mode, the default is now to make just one Ispell process,
2000not one per buffer.
2001
2002** If you use iswitchb but do not call (iswitchb-default-keybindings) to
2003use the default keybindings, you will need to add the following line:
2004 (add-hook 'minibuffer-setup-hook 'iswitchb-minibuffer-setup)
2005
2006** Auto-show mode is no longer enabled just by loading auto-show.el.
2007To control it, set `auto-show-mode' via Custom or use the
2008`auto-show-mode' command.
2009
2010** Handling of X fonts' ascent/descent parameters has been changed to
2011avoid redisplay problems. As a consequence, compared with previous
2012versions the line spacing and frame size now differ with some font
2013choices, typically increasing by a pixel per line. This change
2014occurred in version 20.3 but was not documented then.
2015
2016** If you select the bar cursor style, it uses the frame's
2017cursor-color, rather than the cursor foreground pixel.
2018
2019** In multibyte mode, Rmail decodes incoming MIME messages using the
2020character set specified in the message. If you want to disable this
2021feature, set the variable rmail-decode-mime-charset to nil.
2022
2023** Not new, but not mentioned previously in NEWS: when you use #! at
2024the beginning of a file to make it executable and specify an
2025interpreter program, Emacs looks on the second line for the -*- mode
2026and variable specification, as well as on the first line.
2027
2028** Support for IBM codepage encoding of non-ASCII characters.
2029
2030The new command M-x codepage-setup creates a special coding system
2031that can be used to convert text between a specific IBM codepage and
2032one of the character sets built into Emacs which matches that
2033codepage. For example, codepage 850 corresponds to Latin-1 character
2034set, codepage 855 corresponds to Cyrillic-ISO character set, etc.
2035
2036Windows codepages 1250, 1251 and some others, where Windows deviates
2037from the corresponding ISO character set, are also supported.
2038
2039IBM box-drawing characters and other glyphs which don't have
2040equivalents in the corresponding ISO character set, are converted to
2041a character defined by dos-unsupported-char-glyph on MS-DOS, and to
2042`?' on other systems.
2043
2044IBM codepages are widely used on MS-DOS and MS-Windows, so this
2045feature is most useful on those platforms, but it can also be used on
2046Unix.
2047
2048Emacs compiled for MS-DOS automatically loads the support for the
2049current codepage when it starts.
2050
2051** Mail changes
2052
2053*** The new variable default-sendmail-coding-system specifies the
2054default way to encode outgoing mail. This has higher priority than
2055default-buffer-file-coding-system but has lower priority than
2056sendmail-coding-system and the local value of
2057buffer-file-coding-system.
2058
2059You should not set this variable manually. Instead, set
2060sendmail-coding-system to specify a fixed encoding for all outgoing
2061mail.
2062
2063*** When you try to send a message that contains non-ASCII characters,
2064if the coding system specified by those variables doesn't handle them,
2065Emacs will ask you to select a suitable coding system while showing a
2066list of possible coding systems.
2067
2068** CC Mode changes
2069
2070*** c-default-style can now take an association list that maps major
2071modes to style names. When this variable is an alist, Java mode no
2072longer hardcodes a setting to "java" style. See the variable's
2073docstring for details.
2074
2075*** It's now possible to put a list as the offset on a syntactic
2076symbol. The list is evaluated recursively until a non-nil offset is
2077found. This is useful to combine several lineup functions to act in a
2078prioritized order on a single line. However, none of the supplied
2079lineup functions use this feature currently.
2080
2081*** New syntactic symbol catch-clause, which is used on the "catch" and
2082"finally" lines in try-catch constructs in C++ and Java.
2083
2084*** New cleanup brace-catch-brace on c-cleanup-list, which does for
2085"catch" lines what brace-elseif-brace does for "else if" lines.
2086
2087*** The braces of Java anonymous inner classes are treated separately
2088from the braces of other classes in auto-newline mode. Two new
2089symbols inexpr-class-open and inexpr-class-close may be used on
2090c-hanging-braces-alist to control the automatic newlines used for
2091anonymous classes.
2092
2093*** Support for the Pike language added, along with new Pike specific
2094syntactic symbols: inlambda, lambda-intro-cont
2095
2096*** Support for Java anonymous classes via new syntactic symbol
2097inexpr-class. New syntactic symbol inexpr-statement for Pike
2098support and gcc-style statements inside expressions. New lineup
2099function c-lineup-inexpr-block.
2100
2101*** New syntactic symbol brace-entry-open which is used in brace lists
2102(i.e. static initializers) when a list entry starts with an open
2103brace. These used to be recognized as brace-list-entry's.
2104c-electric-brace also recognizes brace-entry-open braces
2105(brace-list-entry's can no longer be electrified).
2106
2107*** New command c-indent-line-or-region, not bound by default.
2108
2109*** `#' is only electric when typed in the indentation of a line.
2110
2111*** Parentheses are now electric (via the new command c-electric-paren)
2112for auto-reindenting lines when parens are typed.
2113
2114*** In "gnu" style, inline-open offset is now set to zero.
2115
2116*** Uniform handling of the inclass syntactic symbol. The indentation
2117associated with it is now always relative to the class opening brace.
2118This means that the indentation behavior has changed in some
2119circumstances, but only if you've put anything besides 0 on the
2120class-open syntactic symbol (none of the default styles do that).
2121
2122** Gnus changes.
2123
2124*** New functionality for using Gnus as an offline newsreader has been
2125added. A plethora of new commands and modes have been added. See the
2126Gnus manual for the full story.
2127
2128*** The nndraft backend has returned, but works differently than
2129before. All Message buffers are now also articles in the nndraft
2130group, which is created automatically.
2131
2132*** `gnus-alter-header-function' can now be used to alter header
2133values.
2134
2135*** `gnus-summary-goto-article' now accept Message-ID's.
2136
2137*** A new Message command for deleting text in the body of a message
2138outside the region: `C-c C-v'.
2139
2140*** You can now post to component group in nnvirtual groups with
2141`C-u C-c C-c'.
2142
2143*** `nntp-rlogin-program' -- new variable to ease customization.
2144
2145*** `C-u C-c C-c' in `gnus-article-edit-mode' will now inhibit
2146re-highlighting of the article buffer.
2147
2148*** New element in `gnus-boring-article-headers' -- `long-to'.
2149
2150*** `M-i' symbolic prefix command. See the section "Symbolic
2151Prefixes" in the Gnus manual for details.
2152
2153*** `L' and `I' in the summary buffer now take the symbolic prefix
2154`a' to add the score rule to the "all.SCORE" file.
2155
2156*** `gnus-simplify-subject-functions' variable to allow greater
2157control over simplification.
2158
2159*** `A T' -- new command for fetching the current thread.
2160
2161*** `/ T' -- new command for including the current thread in the
2162limit.
2163
2164*** `M-RET' is a new Message command for breaking cited text.
2165
2166*** \\1-expressions are now valid in `nnmail-split-methods'.
2167
2168*** The `custom-face-lookup' function has been removed.
2169If you used this function in your initialization files, you must
2170rewrite them to use `face-spec-set' instead.
2171
2172*** Cancelling now uses the current select method. Symbolic prefix
2173`a' forces normal posting method.
2174
2175*** New command to translate M******** sm*rtq**t*s into proper text
2176-- `W d'.
2177
2178*** For easier debugging of nntp, you can set `nntp-record-commands'
2179to a non-nil value.
2180
2181*** nntp now uses ~/.authinfo, a .netrc-like file, for controlling
2182where and how to send AUTHINFO to NNTP servers.
2183
2184*** A command for editing group parameters from the summary buffer
2185has been added.
2186
2187*** A history of where mails have been split is available.
2188
2189*** A new article date command has been added -- `article-date-iso8601'.
2190
2191*** Subjects can be simplified when threading by setting
2192`gnus-score-thread-simplify'.
2193
2194*** A new function for citing in Message has been added --
2195`message-cite-original-without-signature'.
2196
2197*** `article-strip-all-blank-lines' -- new article command.
2198
2199*** A new Message command to kill to the end of the article has
2200been added.
2201
2202*** A minimum adaptive score can be specified by using the
2203`gnus-adaptive-word-minimum' variable.
2204
2205*** The "lapsed date" article header can be kept continually
2206updated by the `gnus-start-date-timer' command.
2207
2208*** Web listserv archives can be read with the nnlistserv backend.
2209
2210*** Old dejanews archives can now be read by nnweb.
2211
2212*** `gnus-posting-styles' has been re-activated.
2213
2214** Changes to TeX and LaTeX mode
2215
2216*** The new variable `tex-start-options-string' can be used to give
2217options for the TeX run. The default value causes TeX to run in
2218nonstopmode. For an interactive TeX run set it to nil or "".
2219
2220*** The command `tex-feed-input' sends input to the Tex Shell. In a
2221TeX buffer it is bound to the keys C-RET, C-c RET, and C-c C-m (some
2222of these keys may not work on all systems). For instance, if you run
2223TeX interactively and if the TeX run stops because of an error, you
2224can continue it without leaving the TeX buffer by typing C-RET.
2225
2226*** The Tex Shell Buffer is now in `compilation-shell-minor-mode'.
2227All error-parsing commands of the Compilation major mode are available
2228but bound to keys that don't collide with the shell. Thus you can use
2229the Tex Shell for command line executions like a usual shell.
2230
2231*** The commands `tex-validate-region' and `tex-validate-buffer' check
2232the matching of braces and $'s. The errors are listed in a *Occur*
2233buffer and you can use C-c C-c or mouse-2 to go to a particular
2234mismatch.
2235
2236** Changes to RefTeX mode
2237
2238*** The table of contents buffer can now also display labels and
2239file boundaries in addition to sections. Use `l', `i', and `c' keys.
2240
2241*** Labels derived from context (the section heading) are now
2242lowercase by default. To make the label legal in LaTeX, latin-1
2243characters will lose their accent. All Mule characters will be
2244removed from the label.
2245
2246*** The automatic display of cross reference information can also use
2247a window instead of the echo area. See variable `reftex-auto-view-crossref'.
2248
2249*** kpsewhich can be used by RefTeX to find TeX and BibTeX files. See the
2250customization group `reftex-finding-files'.
2251
2252*** The option `reftex-bibfile-ignore-list' has been renamed to
2253`reftex-bibfile-ignore-regexps' and indeed can be fed with regular
2254expressions.
2255
2256*** Multiple Selection buffers are now hidden buffers.
2257
2258** New/deleted modes and packages
2259
2260*** The package snmp-mode.el provides major modes for editing SNMP and
2261SNMPv2 MIBs. It has entries on `auto-mode-alist'.
2262
2263*** The package sql.el provides a major mode, M-x sql-mode, for
2264editing SQL files, and M-x sql-interactive-mode for interacting with
2265SQL interpreters. It has an entry on `auto-mode-alist'.
2266
2267*** M-x highlight-changes-mode provides a minor mode displaying buffer
2268changes with a special face.
2269
2270*** ispell4.el has been deleted. It got in the way of ispell.el and
2271this was hard to fix reliably. It has long been obsolete -- use
2272Ispell 3.1 and ispell.el.
2273\f
2274* MS-DOS changes in Emacs 20.4
2275
2276** Emacs compiled for MS-DOS now supports MULE features better.
2277This includes support for display of all ISO 8859-N character sets,
2278conversion to and from IBM codepage encoding of non-ASCII characters,
2279and automatic setup of the MULE environment at startup. For details,
2280check out the section `MS-DOS and MULE' in the manual.
2281
2282The MS-DOS installation procedure automatically configures and builds
2283Emacs with input method support if it finds an unpacked Leim
2284distribution when the config.bat script is run.
2285
2286** Formerly, the value of lpr-command did not affect printing on
2287MS-DOS unless print-region-function was set to nil, but now it
2288controls whether an external program is invoked or output is written
2289directly to a printer port. Similarly, in the previous version of
2290Emacs, the value of ps-lpr-command did not affect PostScript printing
2291on MS-DOS unless ps-printer-name was set to something other than a
2292string (eg. t or `pipe'), but now it controls whether an external
2293program is used. (These changes were made so that configuration of
2294printing variables would be almost identical across all platforms.)
2295
2296** In the previous version of Emacs, PostScript and non-PostScript
2297output was piped to external programs, but because most print programs
2298available for MS-DOS and MS-Windows cannot read data from their standard
2299input, on those systems the data to be output is now written to a
2300temporary file whose name is passed as the last argument to the external
2301program.
2302
2303An exception is made for `print', a standard program on Windows NT,
2304and `nprint', a standard program on Novell Netware. For both of these
2305programs, the command line is constructed in the appropriate syntax
2306automatically, using only the value of printer-name or ps-printer-name
2307as appropriate--the value of the relevant `-switches' variable is
2308ignored, as both programs have no useful switches.
2309
2310** The value of the variable dos-printer (cf. dos-ps-printer), if it has
2311a value, overrides the value of printer-name (cf. ps-printer-name), on
2312MS-DOS and MS-Windows only. This has been true since version 20.3, but
2313was not documented clearly before.
2314
2315** All the Emacs games now work on MS-DOS terminals.
2316This includes Tetris and Snake.
2317\f
2318* Lisp changes in Emacs 20.4
2319
2320** New functions line-beginning-position and line-end-position
2321return the position of the beginning or end of the current line.
2322They both accept an optional argument, which has the same
2323meaning as the argument to beginning-of-line or end-of-line.
2324
2325** find-file and allied functions now have an optional argument
2326WILDCARD. If this is non-nil, they do wildcard processing,
2327and visit all files that match the wildcard pattern.
2328
2329** Changes in the file-attributes function.
2330
2331*** The file size returned by file-attributes may be an integer or a float.
2332It is an integer if the size fits in a Lisp integer, float otherwise.
2333
2334*** The inode number returned by file-attributes may be an integer (if
2335the number fits in a Lisp integer) or a cons cell containing two
2336integers.
2337
2338** The new function directory-files-and-attributes returns a list of
2339files in a directory and their attributes. It accepts the same
2340arguments as directory-files and has similar semantics, except that
2341file names and attributes are returned.
2342
2343** The new function file-attributes-lessp is a helper function for
2344sorting the list generated by directory-files-and-attributes. It
2345accepts two arguments, each a list of a file name and its atttributes.
2346It compares the file names of each according to string-lessp and
2347returns the result.
2348
2349** The new function file-expand-wildcards expands a wildcard-pattern
2350to produce a list of existing files that match the pattern.
2351
2352** New functions for base64 conversion:
2353
2354The function base64-encode-region converts a part of the buffer
2355into the base64 code used in MIME. base64-decode-region
2356performs the opposite conversion. Line-breaking is supported
2357optionally.
2358
2359Functions base64-encode-string and base64-decode-string do a similar
2360job on the text in a string. They return the value as a new string.
2361
2362**
2363The new function process-running-child-p
2364will tell you if a subprocess has given control of its
2365terminal to its own child process.
2366
2367** interrupt-process and such functions have a new feature:
2368when the second argument is `lambda', they send a signal
2369to the running child of the subshell, if any, but if the shell
2370itself owns its terminal, no signal is sent.
2371
2372** There are new widget types `plist' and `alist' which can
2373be used for customizing variables whose values are plists or alists.
2374
2375** easymenu.el Now understands `:key-sequence' and `:style button'.
2376:included is an alias for :visible.
2377
2378easy-menu-add-item now understands the values returned by
2379easy-menu-remove-item and easy-menu-item-present-p. This can be used
2380to move or copy menu entries.
2381
2382** Multibyte editing changes
2383
2384*** The definitions of sref and char-bytes are changed. Now, sref is
2385an alias of aref and char-bytes always returns 1. This change is to
2386make some Emacs Lisp code which works on 20.2 and earlier also
2387work on the latest Emacs. Such code uses a combination of sref and
2388char-bytes in a loop typically as below:
2389 (setq char (sref str idx)
2390 idx (+ idx (char-bytes idx)))
2391The byte-compiler now warns that this is obsolete.
2392
2393If you want to know how many bytes a specific multibyte character
2394(say, CH) occupies in a multibyte buffer, use this code:
2395 (charset-bytes (char-charset ch))
2396
2397*** In multibyte mode, when you narrow a buffer to some region, and the
2398region is preceded or followed by non-ASCII codes, inserting or
2399deleting at the head or the end of the region may signal this error:
2400
2401 Byte combining across boundary of accessible buffer text inhibitted
2402
2403This is to avoid some bytes being combined together into a character
2404across the boundary.
2405
2406*** The functions find-charset-region and find-charset-string include
2407`unknown' in the returned list in the following cases:
2408 o The current buffer or the target string is unibyte and
2409 contains 8-bit characters.
2410 o The current buffer or the target string is multibyte and
2411 contains invalid characters.
2412
2413*** The functions decode-coding-region and encode-coding-region remove
2414text properties of the target region. Ideally, they should correctly
2415preserve text properties, but for the moment, it's hard. Removing
2416text properties is better than preserving them in a less-than-correct
2417way.
2418
2419*** prefer-coding-system sets EOL conversion of default coding systems.
2420If the argument to prefer-coding-system specifies a certain type of
2421end of line conversion, the default coding systems set by
2422prefer-coding-system will specify that conversion type for end of line.
2423
2424*** The new function thai-compose-string can be used to properly
2425compose Thai characters in a string.
2426
2427** The primitive `define-prefix-command' now takes an optional third
2428argument NAME, which should be a string. It supplies the menu name
2429for the created keymap. Keymaps created in order to be displayed as
2430menus should always use the third argument.
2431
2432** The meanings of optional second arguments for read-char,
2433read-event, and read-char-exclusive are flipped. Now the second
2434arguments are INHERIT-INPUT-METHOD. These functions use the current
2435input method (if any) if and only if INHERIT-INPUT-METHOD is non-nil.
2436
2437** The new function clear-this-command-keys empties out the contents
2438of the vector that (this-command-keys) returns. This is useful in
2439programs that read passwords, to prevent the passwords from echoing
2440inadvertently as part of the next command in certain cases.
2441
2442** The new macro `with-temp-message' displays a temporary message in
2443the echo area, while executing some Lisp code. Like `progn', it
2444returns the value of the last form, but it also restores the previous
2445echo area contents.
2446
2447 (with-temp-message MESSAGE &rest BODY)
2448
2449** The function `require' now takes an optional third argument
2450NOERROR. If it is non-nil, then there is no error if the
2451requested feature cannot be loaded.
2452
2453** In the function modify-face, an argument of (nil) for the
2454foreground color, background color or stipple pattern
2455means to clear out that attribute.
2456
2457** The `outer-window-id' frame property of an X frame
2458gives the window number of the outermost X window for the frame.
2459
2460** Temporary buffers made with with-output-to-temp-buffer are now
2461read-only by default, and normally use the major mode Help mode
2462unless you put them in some other non-Fundamental mode before the
2463end of with-output-to-temp-buffer.
2464
2465** The new functions gap-position and gap-size return information on
2466the gap of the current buffer.
2467
2468** The new functions position-bytes and byte-to-position provide a way
2469to convert between character positions and byte positions in the
2470current buffer.
2471
2472** vc.el defines two new macros, `edit-vc-file' and `with-vc-file', to
2473facilitate working with version-controlled files from Lisp programs.
2474These macros check out a given file automatically if needed, and check
2475it back in after any modifications have been made.
2476\f
2477* Installation Changes in Emacs 20.3
2478
2479** The default value of load-path now includes most subdirectories of
2480the site-specific directories /usr/local/share/emacs/site-lisp and
2481/usr/local/share/emacs/VERSION/site-lisp, in addition to those
2482directories themselves. Both immediate subdirectories and
2483subdirectories multiple levels down are added to load-path.
2484
2485Not all subdirectories are included, though. Subdirectories whose
2486names do not start with a letter or digit are excluded.
2487Subdirectories named RCS or CVS are excluded. Also, a subdirectory
2488which contains a file named `.nosearch' is excluded. You can use
2489these methods to prevent certain subdirectories from being searched.
2490
2491Emacs finds these subdirectories and adds them to load-path when it
2492starts up. While it would be cleaner to find the subdirectories each
2493time Emacs loads a file, that would be much slower.
2494
2495This feature is an incompatible change. If you have stored some Emacs
2496Lisp files in a subdirectory of the site-lisp directory specifically
2497to prevent them from being used, you will need to rename the
2498subdirectory to start with a non-alphanumeric character, or create a
2499`.nosearch' file in it, in order to continue to achieve the desired
2500results.
2501
2502** Emacs no longer includes an old version of the C preprocessor from
2503GCC. This was formerly used to help compile Emacs with C compilers
2504that had limits on the significant length of an identifier, but in
2505fact we stopped supporting such compilers some time ago.
2506\f
2507* Changes in Emacs 20.3
2508
2509** The new command C-x z (repeat) repeats the previous command
2510including its argument. If you repeat the z afterward,
2511it repeats the command additional times; thus, you can
2512perform many repetitions with one keystroke per repetition.
2513
2514** Emacs now supports "selective undo" which undoes only within a
2515specified region. To do this, set point and mark around the desired
2516region and type C-u C-x u (or C-u C-_). You can then continue undoing
2517further, within the same region, by repeating the ordinary undo
2518command C-x u or C-_. This will keep undoing changes that were made
2519within the region you originally specified, until either all of them
2520are undone, or it encounters a change which crosses the edge of that
2521region.
2522
2523In Transient Mark mode, undoing when a region is active requests
2524selective undo.
2525
2526** If you specify --unibyte when starting Emacs, then all buffers are
2527unibyte, except when a Lisp program specifically creates a multibyte
2528buffer. Setting the environment variable EMACS_UNIBYTE has the same
2529effect. The --no-unibyte option overrides EMACS_UNIBYTE and directs
2530Emacs to run normally in multibyte mode.
2531
2532The option --unibyte does not affect the reading of Emacs Lisp files,
2533though. If you want a Lisp file to be read in unibyte mode, use
2534-*-unibyte: t;-*- on its first line. That will force Emacs to
2535load that file in unibyte mode, regardless of how Emacs was started.
2536
2537** toggle-enable-multibyte-characters no longer has a key binding and
2538no longer appears in the menu bar. We've realized that changing the
2539enable-multibyte-characters variable in an existing buffer is
2540something that most users not do.
2541
2542** You can specify a coding system to use for the next cut or paste
2543operations through the window system with the command C-x RET X.
2544The coding system can make a difference for communication with other
2545applications.
2546
2547C-x RET x specifies a coding system for all subsequent cutting and
2548pasting operations.
2549
2550** You can specify the printer to use for commands that do printing by
2551setting the variable `printer-name'. Just what a printer name looks
2552like depends on your operating system. You can specify a different
2553printer for the Postscript printing commands by setting
2554`ps-printer-name'.
2555
2556** Emacs now supports on-the-fly spell checking by the means of a
2557minor mode. It is called M-x flyspell-mode. You don't have to remember
2558any other special commands to use it, and you will hardly notice it
2559except when you make a spelling error. Flyspell works by highlighting
2560incorrect words as soon as they are completed or as soon as the cursor
2561hits a new word.
2562
2563Flyspell mode works with whichever dictionary you have selected for
2564Ispell in Emacs. In TeX mode, it understands TeX syntax so as not
2565to be confused by TeX commands.
2566
2567You can correct a misspelled word by editing it into something
2568correct. You can also correct it, or accept it as correct, by
2569clicking on the word with Mouse-2; that gives you a pop-up menu
2570of various alternative replacements and actions.
2571
2572Flyspell mode also proposes "automatic" corrections. M-TAB replaces
2573the current misspelled word with a possible correction. If several
2574corrections are made possible, M-TAB cycles through them in
2575alphabetical order, or in order of decreasing likelihood if
2576flyspell-sort-corrections is nil.
2577
2578Flyspell mode also flags an error when a word is repeated, if
2579flyspell-mark-duplications-flag is non-nil.
2580
2581** Changes in input method usage.
2582
2583Now you can use arrow keys (right, left, down, up) for selecting among
2584the alternatives just the same way as you do by C-f, C-b, C-n, and C-p
2585respectively.
2586
2587You can use the ENTER key to accept the current conversion.
2588
2589If you type TAB to display a list of alternatives, you can select one
2590of the alternatives with Mouse-2.
2591
2592The meaning of the variable `input-method-verbose-flag' is changed so
2593that you can set it to t, nil, `default', or `complex-only'.
2594
2595 If the value is nil, extra guidance is never given.
2596
2597 If the value is t, extra guidance is always given.
2598
2599 If the value is `complex-only', extra guidance is always given only
2600 when you are using complex input methods such as chinese-py.
2601
2602 If the value is `default' (this is the default), extra guidance is
2603 given in the following case:
2604 o When you are using a complex input method.
2605 o When you are using a simple input method but not in the minibuffer.
2606
2607If you are using Emacs through a very slow line, setting
2608input-method-verbose-flag to nil or to complex-only is a good choice,
2609and if you are using an input method you are not familiar with,
2610setting it to t is helpful.
2611
2612The old command select-input-method is now called set-input-method.
2613
2614In the language environment "Korean", you can use the following
2615keys:
2616 Shift-SPC toggle-korean-input-method
2617 C-F9 quail-hangul-switch-symbol-ksc
2618 F9 quail-hangul-switch-hanja
2619These key bindings are canceled when you switch to another language
2620environment.
2621
2622** The minibuffer history of file names now records the specified file
2623names, not the entire minibuffer input. For example, if the
2624minibuffer starts out with /usr/foo/, you might type in /etc/passwd to
2625get
2626
2627 /usr/foo//etc/passwd
2628
2629which stands for the file /etc/passwd.
2630
2631Formerly, this used to put /usr/foo//etc/passwd in the history list.
2632Now this puts just /etc/passwd in the history list.
2633
2634** If you are root, Emacs sets backup-by-copying-when-mismatch to t
2635at startup, so that saving a file will be sure to preserve
2636its owner and group.
2637
2638** find-func.el can now also find the place of definition of Emacs
2639Lisp variables in user-loaded libraries.
2640
2641** C-x r t (string-rectangle) now deletes the existing rectangle
2642contents before inserting the specified string on each line.
2643
2644** There is a new command delete-whitespace-rectangle
2645which deletes whitespace starting from a particular column
2646in all the lines on a rectangle. The column is specified
2647by the left edge of the rectangle.
2648
2649** You can now store a number into a register with C-u NUMBER C-x r n REG,
2650increment it by INC with C-u INC C-x r + REG (to increment by one, omit
2651C-u INC), and insert it in the buffer with C-x r g REG. This is useful
2652for writing keyboard macros.
2653
2654** The new command M-x speedbar displays a frame in which directories,
2655files, and tags can be displayed, manipulated, and jumped to. The
2656frame defaults to 20 characters in width, and is the same height as
2657the frame that it was started from. Some major modes define
2658additional commands for the speedbar, including Rmail, GUD/GDB, and
2659info.
2660
2661** query-replace-regexp is now bound to C-M-%.
2662
2663** In Transient Mark mode, when the region is active, M-x
2664query-replace and the other replace commands now operate on the region
2665contents only.
2666
2667** M-x write-region, when used interactively, now asks for
2668confirmation before overwriting an existing file. When you call
2669the function from a Lisp program, a new optional argument CONFIRM
2670says whether to ask for confirmation in this case.
2671
2672** If you use find-file-literally and the file is already visited
2673non-literally, the command asks you whether to revisit the file
2674literally. If you say no, it signals an error.
2675
2676** Major modes defined with the "derived mode" feature
2677now use the proper name for the mode hook: WHATEVER-mode-hook.
2678Formerly they used the name WHATEVER-mode-hooks, but that is
2679inconsistent with Emacs conventions.
2680
2681** shell-command-on-region (and shell-command) reports success or
2682failure if the command produces no output.
2683
2684** Set focus-follows-mouse to nil if your window system or window
2685manager does not transfer focus to another window when you just move
2686the mouse.
2687
2688** mouse-menu-buffer-maxlen has been renamed to
2689mouse-buffer-menu-maxlen to be consistent with the other related
2690function and variable names.
2691
2692** The new variable auto-coding-alist specifies coding systems for
2693reading specific files. This has higher priority than
2694file-coding-system-alist.
2695
2696** If you set the variable unibyte-display-via-language-environment to
2697t, then Emacs displays non-ASCII characters are displayed by
2698converting them to the equivalent multibyte characters according to
2699the current language environment. As a result, they are displayed
2700according to the current fontset.
2701
2702** C-q's handling of codes in the range 0200 through 0377 is changed.
2703
2704The codes in the range 0200 through 0237 are inserted as one byte of
2705that code regardless of the values of nonascii-translation-table and
2706nonascii-insert-offset.
2707
2708For the codes in the range 0240 through 0377, if
2709enable-multibyte-characters is non-nil and nonascii-translation-table
2710nor nonascii-insert-offset can't convert them to valid multibyte
2711characters, they are converted to Latin-1 characters.
2712
2713** If you try to find a file that is not read-accessible, you now get
2714an error, rather than an empty buffer and a warning.
2715
2716** In the minibuffer history commands M-r and M-s, an upper case
2717letter in the regular expression forces case-sensitive search.
2718
2719** In the *Help* buffer, cross-references to commands and variables
2720are inferred and hyperlinked. Use C-h m in Help mode for the relevant
2721command keys.
2722
2723** M-x apropos-command, with a prefix argument, no longer looks for
2724user option variables--instead it looks for noninteractive functions.
2725
2726Meanwhile, the command apropos-variable normally searches for
2727user option variables; with a prefix argument, it looks at
2728all variables that have documentation.
2729
2730** When you type a long line in the minibuffer, and the minibuffer
2731shows just one line, automatically scrolling works in a special way
2732that shows you overlap with the previous line of text. The variable
2733minibuffer-scroll-overlap controls how many characters of overlap
2734it should show; the default is 20.
2735
2736Meanwhile, Resize Minibuffer mode is still available; in that mode,
2737the minibuffer grows taller (up to a point) as needed to show the whole
2738of your input.
2739
2740** The new command M-x customize-changed-options lets you customize
2741all the options whose meanings or default values have changed in
2742recent Emacs versions. You specify a previous Emacs version number as
2743argument, and the command creates a customization buffer showing all
2744the customizable options which were changed since that version.
2745Newly added options are included as well.
2746
2747If you don't specify a particular version number argument,
2748then the customization buffer shows all the customizable options
2749for which Emacs versions of changes are recorded.
2750
2751This function is also bound to the Changed Options entry in the
2752Customize menu.
2753
2754** When you run M-x grep with a prefix argument, it figures out
2755the tag around point and puts that into the default grep command.
2756
2757** The new command M-* (pop-tag-mark) pops back through a history of
2758buffer positions from which M-. or other tag-finding commands were
2759invoked.
2760
2761** The new variable comment-padding specifies the number of spaces
2762that `comment-region' will insert before the actual text of the comment.
2763The default is 1.
2764
2765** In Fortran mode the characters `.', `_' and `$' now have symbol
2766syntax, not word syntax. Fortran mode now supports `imenu' and has
2767new commands fortran-join-line (M-^) and fortran-narrow-to-subprogram
2768(C-x n d). M-q can be used to fill a statement or comment block
2769sensibly.
2770
2771** GUD now supports jdb, the Java debugger, and pdb, the Python debugger.
2772
2773** If you set the variable add-log-keep-changes-together to a non-nil
2774value, the command `C-x 4 a' will automatically notice when you make
2775two entries in one day for one file, and combine them.
2776
2777** You can use the command M-x diary-mail-entries to mail yourself a
2778reminder about upcoming diary entries. See the documentation string
2779for a sample shell script for calling this function automatically
2780every night.
2781
2782** All you need to do, to enable use of the Desktop package, is to set
2783the variable desktop-enable to t with Custom.
2784
2785** There is no need to do anything special, now, to enable Gnus to
2786read and post multi-lingual articles.
2787
2788** Outline mode has now support for showing hidden outlines when
2789doing an isearch. In order for this to happen search-invisible should
2790be set to open (the default). If an isearch match is inside a hidden
2791outline the outline is made visible. If you continue pressing C-s and
2792the match moves outside the formerly invisible outline, the outline is
2793made invisible again.
2794
2795** Mail reading and sending changes
2796
2797*** The Rmail e command now switches to displaying the whole header of
2798the message before it lets you edit the message. This is so that any
2799changes you make in the header will not be lost if you subsequently
2800toggle.
2801
2802*** The w command in Rmail, which writes the message body into a file,
2803now works in the summary buffer as well. (The command to delete the
2804summary buffer is now Q.) The default file name for the w command, if
2805the message has no subject, is stored in the variable
2806rmail-default-body-file.
2807
2808*** Most of the commands and modes that operate on mail and netnews no
2809longer depend on the value of mail-header-separator. Instead, they
2810handle whatever separator the buffer happens to use.
2811
2812*** If you set mail-signature to a value which is not t, nil, or a string,
2813it should be an expression. When you send a message, this expression
2814is evaluated to insert the signature.
2815
2816*** The new Lisp library feedmail.el (version 8) enhances processing of
2817outbound email messages. It works in coordination with other email
2818handling packages (e.g., rmail, VM, gnus) and is responsible for
2819putting final touches on messages and actually submitting them for
2820transmission. Users of the emacs program "fakemail" might be
2821especially interested in trying feedmail.
2822
2823feedmail is not enabled by default. See comments at the top of
2824feedmail.el for set-up instructions. Among the bigger features
2825provided by feedmail are:
2826
2827**** you can park outgoing messages into a disk-based queue and
2828stimulate sending some or all of them later (handy for laptop users);
2829there is also a queue for draft messages
2830
2831**** you can get one last look at the prepped outbound message and
2832be prompted for confirmation
2833
2834**** does smart filling of address headers
2835
2836**** can generate a MESSAGE-ID: line and a DATE: line; the date can be
2837the time the message was written or the time it is being sent; this
2838can make FCC copies more closely resemble copies that recipients get
2839
2840**** you can specify an arbitrary function for actually transmitting
2841the message; included in feedmail are interfaces for /bin/[r]mail,
2842/usr/lib/sendmail, and elisp smtpmail; it's easy to write a new
2843function for something else (10-20 lines of elisp)
2844
2845** Dired changes
2846
2847*** The Dired function dired-do-toggle, which toggles marked and unmarked
2848files, is now bound to "t" instead of "T".
2849
2850*** dired-at-point has been added to ffap.el. It allows one to easily
2851run Dired on the directory name at point.
2852
2853*** Dired has a new command: %g. It searches the contents of
2854files in the directory and marks each file that contains a match
2855for a specified regexp.
2856
2857** VC Changes
2858
2859*** New option vc-ignore-vc-files lets you turn off version control
2860conveniently.
2861
2862*** VC Dired has been completely rewritten. It is now much
2863faster, especially for CVS, and works very similar to ordinary
2864Dired.
2865
2866VC Dired is invoked by typing C-x v d and entering the name of the
2867directory to display. By default, VC Dired gives you a recursive
2868listing of all files at or below the given directory which are
2869currently locked (for CVS, all files not up-to-date are shown).
2870
2871You can change the listing format by setting vc-dired-recurse to nil,
2872then it shows only the given directory, and you may also set
2873vc-dired-terse-display to nil, then it shows all files under version
2874control plus the names of any subdirectories, so that you can type `i'
2875on such lines to insert them manually, as in ordinary Dired.
2876
2877All Dired commands operate normally in VC Dired, except for `v', which
2878is redefined as the version control prefix. That means you may type
2879`v l', `v =' etc. to invoke `vc-print-log', `vc-diff' and the like on
2880the file named in the current Dired buffer line. `v v' invokes
2881`vc-next-action' on this file, or on all files currently marked.
2882
2883The new command `v t' (vc-dired-toggle-terse-mode) allows you to
2884toggle between terse display (only locked files) and full display (all
2885VC files plus subdirectories). There is also a special command,
2886`* l', to mark all files currently locked.
2887
2888Giving a prefix argument to C-x v d now does the same thing as in
2889ordinary Dired: it allows you to supply additional options for the ls
2890command in the minibuffer, to fine-tune VC Dired's output.
2891
2892*** Under CVS, if you merge changes from the repository into a working
2893file, and CVS detects conflicts, VC now offers to start an ediff
2894session to resolve them.
2895
2896Alternatively, you can use the new command `vc-resolve-conflicts' to
2897resolve conflicts in a file at any time. It works in any buffer that
2898contains conflict markers as generated by rcsmerge (which is what CVS
2899uses as well).
2900
2901*** You can now transfer changes between branches, using the new
2902command vc-merge (C-x v m). It is implemented for RCS and CVS. When
2903you invoke it in a buffer under version-control, you can specify
2904either an entire branch or a pair of versions, and the changes on that
2905branch or between the two versions are merged into the working file.
2906If this results in any conflicts, they may be resolved interactively,
2907using ediff.
2908
2909** Changes in Font Lock
2910
2911*** The face and variable previously known as font-lock-reference-face
2912are now called font-lock-constant-face to better reflect their typical
2913use for highlighting constants and labels. (Its face properties are
2914unchanged.) The variable font-lock-reference-face remains for now for
2915compatibility reasons, but its value is font-lock-constant-face.
2916
2917** Frame name display changes
2918
2919*** The command set-frame-name lets you set the name of the current
2920frame. You can use the new command select-frame-by-name to select and
2921raise a frame; this is mostly useful on character-only terminals, or
2922when many frames are invisible or iconified.
2923
2924*** On character-only terminal (not a window system), changing the
2925frame name is now reflected on the mode line and in the Buffers/Frames
2926menu.
2927
2928** Comint (subshell) changes
2929
2930*** In Comint modes, the commands to kill, stop or interrupt a
2931subjob now also kill pending input. This is for compatibility
2932with ordinary shells, where the signal characters do this.
2933
2934*** There are new commands in Comint mode.
2935
2936C-c C-x fetches the "next" line from the input history;
2937that is, the line after the last line you got.
2938You can use this command to fetch successive lines, one by one.
2939
2940C-c SPC accumulates lines of input. More precisely, it arranges to
2941send the current line together with the following line, when you send
2942the following line.
2943
2944C-c C-a if repeated twice consecutively now moves to the process mark,
2945which separates the pending input from the subprocess output and the
2946previously sent input.
2947
2948C-c M-r now runs comint-previous-matching-input-from-input;
2949it searches for a previous command, using the current pending input
2950as the search string.
2951
2952*** New option compilation-scroll-output can be set to scroll
2953automatically in compilation-mode windows.
2954
2955** C mode changes
2956
2957*** Multiline macros are now handled, both as they affect indentation,
2958and as recognized syntax. New syntactic symbol cpp-macro-cont is
2959assigned to second and subsequent lines of a multiline macro
2960definition.
2961
2962*** A new style "user" which captures all non-hook-ified
2963(i.e. top-level) .emacs file variable settings and customizations.
2964Style "cc-mode" is an alias for "user" and is deprecated. "gnu"
2965style is still the default however.
2966
2967*** "java" style now conforms to Sun's JDK coding style.
2968
2969*** There are new commands c-beginning-of-defun, c-end-of-defun which
2970are alternatives which you could bind to C-M-a and C-M-e if you prefer
2971them. They do not have key bindings by default.
2972
2973*** New and improved implementations of M-a (c-beginning-of-statement)
2974and M-e (c-end-of-statement).
2975
2976*** C++ namespace blocks are supported, with new syntactic symbols
2977namespace-open, namespace-close, and innamespace.
2978
2979*** File local variable settings of c-file-style and c-file-offsets
2980makes the style variables local to that buffer only.
2981
2982*** New indentation functions c-lineup-close-paren,
2983c-indent-one-line-block, c-lineup-dont-change.
2984
2985*** Improvements (hopefully!) to the way CC Mode is loaded. You
2986should now be able to do a (require 'cc-mode) to get the entire
2987package loaded properly for customization in your .emacs file. A new
2988variable c-initialize-on-load controls this and is t by default.
2989
2990** Changes to hippie-expand.
2991
2992*** New customization variable `hippie-expand-dabbrev-skip-space'. If
2993non-nil, trailing spaces may be included in the abbreviation to search for,
2994which then gives the same behavior as the original `dabbrev-expand'.
2995
2996*** New customization variable `hippie-expand-dabbrev-as-symbol'. If
2997non-nil, characters of syntax '_' is considered part of the word when
2998expanding dynamically.
2999
3000*** New customization variable `hippie-expand-no-restriction'. If
3001non-nil, narrowed buffers are widened before they are searched.
3002
3003*** New customization variable `hippie-expand-only-buffers'. If
3004non-empty, buffers searched are restricted to the types specified in
3005this list. Useful for example when constructing new special-purpose
3006expansion functions with `make-hippie-expand-function'.
3007
3008*** Text properties of the expansion are no longer copied.
3009
3010** Changes in BibTeX mode.
3011
3012*** Any titleword matching a regexp in the new variable
3013bibtex-autokey-titleword-ignore (case sensitive) is ignored during
3014automatic key generation. This replaces variable
3015bibtex-autokey-titleword-first-ignore, which only checked for matches
3016against the first word in the title.
3017
3018*** Autokey generation now uses all words from the title, not just
3019capitalized words. To avoid conflicts with existing customizations,
3020bibtex-autokey-titleword-ignore is set up such that words starting with
3021lowerkey characters will still be ignored. Thus, if you want to use
3022lowercase words from the title, you will have to overwrite the
3023bibtex-autokey-titleword-ignore standard setting.
3024
3025*** Case conversion of names and title words for automatic key
3026generation is more flexible. Variable bibtex-autokey-preserve-case is
3027replaced by bibtex-autokey-titleword-case-convert and
3028bibtex-autokey-name-case-convert.
3029
3030** Changes in vcursor.el.
3031
3032*** Support for character terminals is available: there is a new keymap
3033and the vcursor will appear as an arrow between buffer text. A
3034variable `vcursor-interpret-input' allows input from the vcursor to be
3035entered exactly as if typed. Numerous functions, including
3036`vcursor-compare-windows', have been rewritten to improve consistency
3037in the selection of windows and corresponding keymaps.
3038
3039*** vcursor options can now be altered with M-x customize under the
3040Editing group once the package is loaded.
3041
3042*** Loading vcursor now does not define keys by default, as this is
3043generally a bad side effect. Use M-x customize to set
3044vcursor-key-bindings to t to restore the old behaviour.
3045
3046*** vcursor-auto-disable can be `copy', which turns off copying from the
3047vcursor, but doesn't disable it, after any non-vcursor command.
3048
3049** Ispell changes.
3050
3051*** You can now spell check comments and strings in the current
3052buffer with M-x ispell-comments-and-strings. Comments and strings
3053are identified by syntax tables in effect.
3054
3055*** Generic region skipping implemented.
3056A single buffer can be broken into a number of regions where text will
3057and will not be checked. The definitions of the regions can be user
3058defined. New applications and improvements made available by this
3059include:
3060
3061 o URLs are automatically skipped
3062 o EMail message checking is vastly improved.
3063
3064*** Ispell can highlight the erroneous word even on non-window terminals.
3065
3066** Changes to RefTeX mode
3067
3068RefTeX has been updated in order to make it more usable with very
3069large projects (like a several volume math book). The parser has been
3070re-written from scratch. To get maximum speed from RefTeX, check the
3071section `Optimizations' in the manual.
3072
3073*** New recursive parser.
3074
3075The old version of RefTeX created a single large buffer containing the
3076entire multifile document in order to parse the document. The new
3077recursive parser scans the individual files.
3078
3079*** Parsing only part of a document.
3080
3081Reparsing of changed document parts can now be made faster by enabling
3082partial scans. To use this feature, read the documentation string of
3083the variable `reftex-enable-partial-scans' and set the variable to t.
3084
3085 (setq reftex-enable-partial-scans t)
3086
3087*** Storing parsing information in a file.
3088
3089This can improve startup times considerably. To turn it on, use
3090
3091 (setq reftex-save-parse-info t)
3092
3093*** Using multiple selection buffers
3094
3095If the creation of label selection buffers is too slow (this happens
3096for large documents), you can reuse these buffers by setting
3097
3098 (setq reftex-use-multiple-selection-buffers t)
3099
3100*** References to external documents.
3101
3102The LaTeX package `xr' allows to cross-reference labels in external
3103documents. RefTeX can provide information about the external
3104documents as well. To use this feature, set up the \externaldocument
3105macros required by the `xr' package and rescan the document with
3106RefTeX. The external labels can then be accessed with the `x' key in
3107the selection buffer provided by `reftex-reference' (bound to `C-c )').
3108The `x' key also works in the table of contents buffer.
3109
3110*** Many more labeled LaTeX environments are recognized by default.
3111
3112The builtin command list now covers all the standard LaTeX commands,
3113and all of the major packages included in the LaTeX distribution.
3114
3115Also, RefTeX now understands the \appendix macro and changes
3116the enumeration of sections in the *toc* buffer accordingly.
3117
3118*** Mouse support for selection and *toc* buffers
3119
3120The mouse can now be used to select items in the selection and *toc*
3121buffers. See also the new option `reftex-highlight-selection'.
3122
3123*** New keymaps for selection and table of contents modes.
3124
3125The selection processes for labels and citation keys, and the table of
3126contents buffer now have their own keymaps: `reftex-select-label-map',
3127`reftex-select-bib-map', `reftex-toc-map'. The selection processes
3128have a number of new keys predefined. In particular, TAB lets you
3129enter a label with completion. Check the on-the-fly help (press `?'
3130at the selection prompt) or read the Info documentation to find out
3131more.
3132
3133*** Support for the varioref package
3134
3135The `v' key in the label selection buffer toggles \ref versus \vref.
3136
3137*** New hooks
3138
3139Three new hooks can be used to redefine the way labels, references,
3140and citations are created. These hooks are
3141`reftex-format-label-function', `reftex-format-ref-function',
3142`reftex-format-cite-function'.
3143
3144*** Citations outside LaTeX
3145
3146The command `reftex-citation' may also be used outside LaTeX (e.g. in
3147a mail buffer). See the Info documentation for details.
3148
3149*** Short context is no longer fontified.
3150
3151The short context in the label menu no longer copies the
3152fontification from the text in the buffer. If you prefer it to be
3153fontified, use
3154
3155 (setq reftex-refontify-context t)
3156
3157** file-cache-minibuffer-complete now accepts a prefix argument.
3158With a prefix argument, it does not try to do completion of
3159the file name within its directory; it only checks for other
3160directories that contain the same file name.
3161
3162Thus, given the file name Makefile, and assuming that a file
3163Makefile.in exists in the same directory, ordinary
3164file-cache-minibuffer-complete will try to complete Makefile to
3165Makefile.in and will therefore never look for other directories that
3166have Makefile. A prefix argument tells it not to look for longer
3167names such as Makefile.in, so that instead it will look for other
3168directories--just as if the name were already complete in its present
3169directory.
3170
3171** New modes and packages
3172
3173*** There is a new alternative major mode for Perl, Cperl mode.
3174It has many more features than Perl mode, and some people prefer
3175it, but some do not.
3176
3177*** There is a new major mode, M-x vhdl-mode, for editing files of VHDL
3178code.
3179
3180*** M-x which-function-mode enables a minor mode that displays the
3181current function name continuously in the mode line, as you move
3182around in a buffer.
3183
3184Which Function mode is effective in major modes which support Imenu.
3185
3186*** Gametree is a major mode for editing game analysis trees. The author
3187uses it for keeping notes about his postal Chess games, but it should
3188be helpful for other two-player games as well, as long as they have an
3189established system of notation similar to Chess.
3190
3191*** The new minor mode checkdoc-minor-mode provides Emacs Lisp
3192documentation string checking for style and spelling. The style
3193guidelines are found in the Emacs Lisp programming manual.
3194
3195*** The net-utils package makes some common networking features
3196available in Emacs. Some of these functions are wrappers around
3197system utilities (ping, nslookup, etc); others are implementations of
3198simple protocols (finger, whois) in Emacs Lisp. There are also
3199functions to make simple connections to TCP/IP ports for debugging and
3200the like.
3201
3202*** highlight-changes-mode is a minor mode that uses colors to
3203identify recently changed parts of the buffer text.
3204
3205*** The new package `midnight' lets you specify things to be done
3206within Emacs at midnight--by default, kill buffers that you have not
3207used in a considerable time. To use this feature, customize
3208the user option `midnight-mode' to t.
3209
3210*** The file generic-x.el defines a number of simple major modes.
3211
3212 apache-generic-mode: For Apache and NCSA httpd configuration files
3213 samba-generic-mode: Samba configuration files
3214 fvwm-generic-mode: For fvwm initialization files
3215 x-resource-generic-mode: For X resource files
3216 hosts-generic-mode: For hosts files (.rhosts, /etc/hosts, etc)
3217 mailagent-rules-generic-mode: For mailagent .rules files
3218 javascript-generic-mode: For JavaScript files
3219 vrml-generic-mode: For VRML files
3220 java-manifest-generic-mode: For Java MANIFEST files
3221 java-properties-generic-mode: For Java property files
3222 mailrc-generic-mode: For .mailrc files
3223
3224 Platform-specific modes:
3225
3226 prototype-generic-mode: For Solaris/Sys V prototype files
3227 pkginfo-generic-mode: For Solaris/Sys V pkginfo files
3228 alias-generic-mode: For C shell alias files
3229 inf-generic-mode: For MS-Windows INF files
3230 ini-generic-mode: For MS-Windows INI files
3231 reg-generic-mode: For MS-Windows Registry files
3232 bat-generic-mode: For MS-Windows BAT scripts
3233 rc-generic-mode: For MS-Windows Resource files
3234 rul-generic-mode: For InstallShield scripts
3235\f
3236* Lisp changes in Emacs 20.3 since the Emacs Lisp Manual was published
3237
3238** If you want a Lisp file to be read in unibyte mode,
3239use -*-unibyte: t;-*- on its first line.
3240That will force Emacs to read that file in unibyte mode.
3241Otherwise, the file will be loaded and byte-compiled in multibyte mode.
3242
3243Thus, each lisp file is read in a consistent way regardless of whether
3244you started Emacs with --unibyte, so that a Lisp program gives
3245consistent results regardless of how Emacs was started.
3246
3247** The new function assoc-default is useful for searching an alist,
3248and using a default value if the key is not found there. You can
3249specify a comparison predicate, so this function is useful for
3250searching comparing a string against an alist of regular expressions.
3251
3252** The functions unibyte-char-to-multibyte and
3253multibyte-char-to-unibyte convert between unibyte and multibyte
3254character codes, in a way that is appropriate for the current language
3255environment.
3256
3257** The functions read-event, read-char and read-char-exclusive now
3258take two optional arguments. PROMPT, if non-nil, specifies a prompt
3259string. SUPPRESS-INPUT-METHOD, if non-nil, says to disable the
3260current input method for reading this one event.
3261
3262** Two new variables print-escape-nonascii and print-escape-multibyte
3263now control whether to output certain characters as
3264backslash-sequences. print-escape-nonascii applies to single-byte
3265non-ASCII characters; print-escape-multibyte applies to multibyte
3266characters. Both of these variables are used only when printing
3267in readable fashion (prin1 uses them, princ does not).
3268\f
3269* Lisp changes in Emacs 20.3 before the Emacs Lisp Manual was published
3270
3271** Compiled Emacs Lisp files made with the modified "MBSK" version
3272of Emacs 20.2 do not work in Emacs 20.3.
3273
3274** Buffer positions are now measured in characters, as they were
3275in Emacs 19 and before. This means that (forward-char 1)
3276always increases point by 1.
3277
3278The function chars-in-region now just subtracts its arguments. It is
3279considered obsolete. The function char-boundary-p has been deleted.
3280
3281See below for additional changes relating to multibyte characters.
3282
3283** defcustom, defface and defgroup now accept the keyword `:version'.
3284Use this to specify in which version of Emacs a certain variable's
3285default value changed. For example,
3286
3287 (defcustom foo-max 34 "*Maximum number of foo's allowed."
3288 :type 'integer
3289 :group 'foo
3290 :version "20.3")
3291
3292 (defgroup foo-group nil "The foo group."
3293 :version "20.3")
3294
3295If an entire new group is added or the variables in it have the
3296default values changed, then just add a `:version' to that group. It
3297is recommended that new packages added to the distribution contain a
3298`:version' in the top level group.
3299
3300This information is used to control the customize-changed-options command.
3301
3302** It is now an error to change the value of a symbol whose name
3303starts with a colon--if it is interned in the standard obarray.
3304
3305However, setting such a symbol to its proper value, which is that
3306symbol itself, is not an error. This is for the sake of programs that
3307support previous Emacs versions by explicitly setting these variables
3308to themselves.
3309
3310If you set the variable keyword-symbols-constant-flag to nil,
3311this error is suppressed, and you can set these symbols to any
3312values whatever.
3313
3314** There is a new debugger command, R.
3315It evaluates an expression like e, but saves the result
3316in the buffer *Debugger-record*.
3317
3318** Frame-local variables.
3319
3320You can now make a variable local to various frames. To do this, call
3321the function make-variable-frame-local; this enables frames to have
3322local bindings for that variable.
3323
3324These frame-local bindings are actually frame parameters: you create a
3325frame-local binding in a specific frame by calling
3326modify-frame-parameters and specifying the variable name as the
3327parameter name.
3328
3329Buffer-local bindings take precedence over frame-local bindings.
3330Thus, if the current buffer has a buffer-local binding, that binding is
3331active; otherwise, if the selected frame has a frame-local binding,
3332that binding is active; otherwise, the default binding is active.
3333
3334It would not be hard to implement window-local bindings, but it is not
3335clear that this would be very useful; windows tend to come and go in a
3336very transitory fashion, so that trying to produce any specific effect
3337through a window-local binding would not be very robust.
3338
3339** `sregexq' and `sregex' are two new functions for constructing
3340"symbolic regular expressions." These are Lisp expressions that, when
3341evaluated, yield conventional string-based regexps. The symbolic form
3342makes it easier to construct, read, and maintain complex patterns.
3343See the documentation in sregex.el.
3344
3345** parse-partial-sexp's return value has an additional element which
3346is used to pass information along if you pass it to another call to
3347parse-partial-sexp, starting its scan where the first call ended.
3348The contents of this field are not yet finalized.
3349
3350** eval-region now accepts a fourth optional argument READ-FUNCTION.
3351If it is non-nil, that function is used instead of `read'.
3352
3353** unload-feature by default removes the feature's functions from
3354known hooks to avoid trouble, but a package providing FEATURE can
3355define a hook FEATURE-unload-hook to be run by unload-feature instead.
3356
3357** read-from-minibuffer no longer returns the argument DEFAULT-VALUE
3358when the user enters empty input. It now returns the null string, as
3359it did in Emacs 19. The default value is made available in the
3360history via M-n, but it is not applied here as a default.
3361
3362The other, more specialized minibuffer-reading functions continue to
3363return the default value (not the null string) when the user enters
3364empty input.
3365
3366** The new variable read-buffer-function controls which routine to use
3367for selecting buffers. For example, if you set this variable to
3368`iswitchb-read-buffer', iswitchb will be used to read buffer names.
3369Other functions can also be used if they accept the same arguments as
3370`read-buffer' and return the selected buffer name as a string.
3371
3372** The new function read-passwd reads a password from the terminal,
3373echoing a period for each character typed. It takes three arguments:
3374a prompt string, a flag which says "read it twice to make sure", and a
3375default password to use if the user enters nothing.
3376
3377** The variable fill-nobreak-predicate gives major modes a way to
3378specify not to break a line at certain places. Its value is a
3379function which is called with no arguments, with point located at the
3380place where a break is being considered. If the function returns
3381non-nil, then the line won't be broken there.
3382
3383** window-end now takes an optional second argument, UPDATE.
3384If this is non-nil, then the function always returns an accurate
3385up-to-date value for the buffer position corresponding to the
3386end of the window, even if this requires computation.
3387
3388** other-buffer now takes an optional argument FRAME
3389which specifies which frame's buffer list to use.
3390If it is nil, that means use the selected frame's buffer list.
3391
3392** The new variable buffer-display-time, always local in every buffer,
3393holds the value of (current-time) as of the last time that a window
3394was directed to display this buffer.
3395
3396** It is now meaningful to compare two window-configuration objects
3397with `equal'. Two window-configuration objects are equal if they
3398describe equivalent arrangements of windows, in the same frame--in
3399other words, if they would give the same results if passed to
3400set-window-configuration.
3401
3402** compare-window-configurations is a new function that compares two
3403window configurations loosely. It ignores differences in saved buffer
3404positions and scrolling, and considers only the structure and sizes of
3405windows and the choice of buffers to display.
3406
3407** The variable minor-mode-overriding-map-alist allows major modes to
3408override the key bindings of a minor mode. The elements of this alist
3409look like the elements of minor-mode-map-alist: (VARIABLE . KEYMAP).
3410
3411If the VARIABLE in an element of minor-mode-overriding-map-alist has a
3412non-nil value, the paired KEYMAP is active, and totally overrides the
3413map (if any) specified for the same variable in minor-mode-map-alist.
3414
3415minor-mode-overriding-map-alist is automatically local in all buffers,
3416and it is meant to be set by major modes.
3417
3418** The function match-string-no-properties is like match-string
3419except that it discards all text properties from the result.
3420
3421** The function load-average now accepts an optional argument
3422USE-FLOATS. If it is non-nil, the load average values are returned as
3423floating point numbers, rather than as integers to be divided by 100.
3424
3425** The new variable temporary-file-directory specifies the directory
3426to use for creating temporary files. The default value is determined
3427in a reasonable way for your operating system; on GNU and Unix systems
3428it is based on the TMP and TMPDIR environment variables.
3429
3430** Menu changes
3431
3432*** easymenu.el now uses the new menu item format and supports the
3433keywords :visible and :filter. The existing keyword :keys is now
3434better supported.
3435
3436The variable `easy-menu-precalculate-equivalent-keybindings' controls
3437a new feature which calculates keyboard equivalents for the menu when
3438you define the menu. The default is t. If you rarely use menus, you
3439can set the variable to nil to disable this precalculation feature;
3440then the calculation is done only if you use the menu bar.
3441
3442*** A new format for menu items is supported.
3443
3444In a keymap, a key binding that has the format
3445 (STRING . REAL-BINDING) or (STRING HELP-STRING . REAL-BINDING)
3446defines a menu item. Now a menu item definition may also be a list that
3447starts with the symbol `menu-item'.
3448
3449The format is:
3450 (menu-item ITEM-NAME) or
3451 (menu-item ITEM-NAME REAL-BINDING . ITEM-PROPERTY-LIST)
3452where ITEM-NAME is an expression which evaluates to the menu item
3453string, and ITEM-PROPERTY-LIST has the form of a property list.
3454The supported properties include
3455
3456:enable FORM Evaluate FORM to determine whether the
3457 item is enabled.
3458:visible FORM Evaluate FORM to determine whether the
3459 item should appear in the menu.
3460:filter FILTER-FN
3461 FILTER-FN is a function of one argument,
3462 which will be REAL-BINDING.
3463 It should return a binding to use instead.
3464:keys DESCRIPTION
3465 DESCRIPTION is a string that describes an equivalent keyboard
3466 binding for for REAL-BINDING. DESCRIPTION is expanded with
3467 `substitute-command-keys' before it is used.
3468:key-sequence KEY-SEQUENCE
3469 KEY-SEQUENCE is a key-sequence for an equivalent
3470 keyboard binding.
3471:key-sequence nil
3472 This means that the command normally has no
3473 keyboard equivalent.
3474:help HELP HELP is the extra help string (not currently used).
3475:button (TYPE . SELECTED)
3476 TYPE is :toggle or :radio.
3477 SELECTED is a form, to be evaluated, and its
3478 value says whether this button is currently selected.
3479
3480Buttons are at the moment only simulated by prefixes in the menu.
3481Eventually ordinary X-buttons may be supported.
3482
3483(menu-item ITEM-NAME) defines unselectable item.
3484
3485** New event types
3486
3487*** The new event type `mouse-wheel' is generated by a wheel on a
3488mouse (such as the MS Intellimouse). The event contains a delta that
3489corresponds to the amount and direction that the wheel is rotated,
3490which is typically used to implement a scroll or zoom. The format is:
3491
3492 (mouse-wheel POSITION DELTA)
3493
3494where POSITION is a list describing the position of the event in the
3495same format as a mouse-click event, and DELTA is a signed number
3496indicating the number of increments by which the wheel was rotated. A
3497negative DELTA indicates that the wheel was rotated backwards, towards
3498the user, and a positive DELTA indicates that the wheel was rotated
3499forward, away from the user.
3500
3501As of now, this event type is generated only on MS Windows.
3502
3503*** The new event type `drag-n-drop' is generated when a group of
3504files is selected in an application outside of Emacs, and then dragged
3505and dropped onto an Emacs frame. The event contains a list of
3506filenames that were dragged and dropped, which are then typically
3507loaded into Emacs. The format is:
3508
3509 (drag-n-drop POSITION FILES)
3510
3511where POSITION is a list describing the position of the event in the
3512same format as a mouse-click event, and FILES is the list of filenames
3513that were dragged and dropped.
3514
3515As of now, this event type is generated only on MS Windows.
3516
3517** Changes relating to multibyte characters.
3518
3519*** The variable enable-multibyte-characters is now read-only;
3520any attempt to set it directly signals an error. The only way
3521to change this value in an existing buffer is with set-buffer-multibyte.
3522
3523*** In a string constant, `\ ' now stands for "nothing at all". You
3524can use it to terminate a hex escape which is followed by a character
3525that could otherwise be read as part of the hex escape.
3526
3527*** String indices are now measured in characters, as they were
3528in Emacs 19 and before.
3529
3530The function chars-in-string has been deleted.
3531The function concat-chars has been renamed to `string'.
3532
3533*** The function set-buffer-multibyte sets the flag in the current
3534buffer that says whether the buffer uses multibyte representation or
3535unibyte representation. If the argument is nil, it selects unibyte
3536representation. Otherwise it selects multibyte representation.
3537
3538This function does not change the contents of the buffer, viewed
3539as a sequence of bytes. However, it does change the contents
3540viewed as characters; a sequence of two bytes which is treated as
3541one character when the buffer uses multibyte representation
3542will count as two characters using unibyte representation.
3543
3544This function sets enable-multibyte-characters to record which
3545representation is in use. It also adjusts various data in the buffer
3546(including its markers, overlays and text properties) so that they are
3547consistent with the new representation.
3548
3549*** string-make-multibyte takes a string and converts it to multibyte
3550representation. Most of the time, you don't need to care
3551about the representation, because Emacs converts when necessary;
3552however, it makes a difference when you compare strings.
3553
3554The conversion of non-ASCII characters works by adding the value of
3555nonascii-insert-offset to each character, or by translating them
3556using the table nonascii-translation-table.
3557
3558*** string-make-unibyte takes a string and converts it to unibyte
3559representation. Most of the time, you don't need to care about the
3560representation, but it makes a difference when you compare strings.
3561
3562The conversion from multibyte to unibyte representation
3563loses information; the only time Emacs performs it automatically
3564is when inserting a multibyte string into a unibyte buffer.
3565
3566*** string-as-multibyte takes a string, and returns another string
3567which contains the same bytes, but treats them as multibyte.
3568
3569*** string-as-unibyte takes a string, and returns another string
3570which contains the same bytes, but treats them as unibyte.
3571
3572*** The new function compare-strings lets you compare
3573portions of two strings. Unibyte strings are converted to multibyte,
3574so that a unibyte string can match a multibyte string.
3575You can specify whether to ignore case or not.
3576
3577*** assoc-ignore-case now uses compare-strings so that
3578it can treat unibyte and multibyte strings as equal.
3579
3580*** Regular expression operations and buffer string searches now
3581convert the search pattern to multibyte or unibyte to accord with the
3582buffer or string being searched.
3583
3584One consequence is that you cannot always use \200-\377 inside of
3585[...] to match all non-ASCII characters. This does still work when
3586searching or matching a unibyte buffer or string, but not when
3587searching or matching a multibyte string. Unfortunately, there is no
3588obvious choice of syntax to use within [...] for that job. But, what
3589you want is just to match all non-ASCII characters, the regular
3590expression [^\0-\177] works for it.
3591
3592*** Structure of coding system changed.
3593
3594All coding systems (including aliases and subsidiaries) are named
3595by symbols; the symbol's `coding-system' property is a vector
3596which defines the coding system. Aliases share the same vector
3597as the principal name, so that altering the contents of this
3598vector affects the principal name and its aliases. You can define
3599your own alias name of a coding system by the function
3600define-coding-system-alias.
3601
3602The coding system definition includes a property list of its own. Use
3603the new functions `coding-system-get' and `coding-system-put' to
3604access such coding system properties as post-read-conversion,
3605pre-write-conversion, character-translation-table-for-decode,
3606character-translation-table-for-encode, mime-charset, and
3607safe-charsets. For instance, (coding-system-get 'iso-latin-1
3608'mime-charset) gives the corresponding MIME-charset parameter
3609`iso-8859-1'.
3610
3611Among the coding system properties listed above, safe-charsets is new.
3612The value of this property is a list of character sets which this
3613coding system can correctly encode and decode. For instance:
3614(coding-system-get 'iso-latin-1 'safe-charsets) => (ascii latin-iso8859-1)
3615
3616Here, "correctly encode" means that the encoded character sets can
3617also be handled safely by systems other than Emacs as far as they
3618are capable of that coding system. Though, Emacs itself can encode
3619the other character sets and read it back correctly.
3620
3621*** The new function select-safe-coding-system can be used to find a
3622proper coding system for encoding the specified region or string.
3623This function requires a user interaction.
3624
3625*** The new functions find-coding-systems-region and
3626find-coding-systems-string are helper functions used by
3627select-safe-coding-system. They return a list of all proper coding
3628systems to encode a text in some region or string. If you don't want
3629a user interaction, use one of these functions instead of
3630select-safe-coding-system.
3631
3632*** The explicit encoding and decoding functions, such as
3633decode-coding-region and encode-coding-string, now set
3634last-coding-system-used to reflect the actual way encoding or decoding
3635was done.
3636
3637*** The new function detect-coding-with-language-environment can be
3638used to detect a coding system of text according to priorities of
3639coding systems used by some specific language environment.
3640
3641*** The functions detect-coding-region and detect-coding-string always
3642return a list if the arg HIGHEST is nil. Thus, if only ASCII
3643characters are found, they now return a list of single element
3644`undecided' or its subsidiaries.
3645
3646*** The new functions coding-system-change-eol-conversion and
3647coding-system-change-text-conversion can be used to get a different
3648coding system than what specified only in how end-of-line or text is
3649converted.
3650
3651*** The new function set-selection-coding-system can be used to set a
3652coding system for communicating with other X clients.
3653
3654*** The function `map-char-table' now passes as argument only valid
3655character codes, plus generic characters that stand for entire
3656character sets or entire subrows of a character set. In other words,
3657each time `map-char-table' calls its FUNCTION argument, the key value
3658either will be a valid individual character code, or will stand for a
3659range of characters.
3660
3661*** The new function `char-valid-p' can be used for checking whether a
3662Lisp object is a valid character code or not.
3663
3664*** The new function `charset-after' returns a charset of a character
3665in the current buffer at position POS.
3666
3667*** Input methods are now implemented using the variable
3668input-method-function. If this is non-nil, its value should be a
3669function; then, whenever Emacs reads an input event that is a printing
3670character with no modifier bits, it calls that function, passing the
3671event as an argument. Often this function will read more input, first
3672binding input-method-function to nil.
3673
3674The return value should be a list of the events resulting from input
3675method processing. These events will be processed sequentially as
3676input, before resorting to unread-command-events. Events returned by
3677the input method function are not passed to the input method function,
3678not even if they are printing characters with no modifier bits.
3679
3680The input method function is not called when reading the second and
3681subsequent events of a key sequence.
3682
3683*** You can customize any language environment by using
3684set-language-environment-hook and exit-language-environment-hook.
3685
3686The hook `exit-language-environment-hook' should be used to undo
3687customizations that you made with set-language-environment-hook. For
3688instance, if you set up a special key binding for a specific language
3689environment by set-language-environment-hook, you should set up
3690exit-language-environment-hook to restore the normal key binding.
3691\f
3692* Changes in Emacs 20.1
3693
3694** Emacs has a new facility for customization of its many user
3695options. It is called M-x customize. With this facility you can look
3696at the many user options in an organized way; they are grouped into a
3697tree structure.
3698
3699M-x customize also knows what sorts of values are legitimate for each
3700user option and ensures that you don't use invalid values.
3701
3702With M-x customize, you can set options either for the present Emacs
3703session or permanently. (Permanent settings are stored automatically
3704in your .emacs file.)
3705
3706** Scroll bars are now on the left side of the window.
3707You can change this with M-x customize-option scroll-bar-mode.
3708
3709** The mode line no longer includes the string `Emacs'.
3710This makes more space in the mode line for other information.
3711
3712** When you select a region with the mouse, it is highlighted
3713immediately afterward. At that time, if you type the DELETE key, it
3714kills the region.
3715
3716The BACKSPACE key, and the ASCII character DEL, do not do this; they
3717delete the character before point, as usual.
3718
3719** In an incremental search the whole current match is highlighted
3720on terminals which support this. (You can disable this feature
3721by setting search-highlight to nil.)
3722
3723** In the minibuffer, in some cases, you can now use M-n to
3724insert the default value into the minibuffer as text. In effect,
3725the default value (if the minibuffer routines know it) is tacked
3726onto the history "in the future". (The more normal use of the
3727history list is to use M-p to insert minibuffer input used in the
3728past.)
3729
3730** In Text mode, now only blank lines separate paragraphs.
3731This makes it possible to get the full benefit of Adaptive Fill mode
3732in Text mode, and other modes derived from it (such as Mail mode).
3733TAB in Text mode now runs the command indent-relative; this
3734makes a practical difference only when you use indented paragraphs.
3735
3736As a result, the old Indented Text mode is now identical to Text mode,
3737and is an alias for it.
3738
3739If you want spaces at the beginning of a line to start a paragraph,
3740use the new mode, Paragraph Indent Text mode.
3741
3742** Scrolling changes
3743
3744*** Scroll commands to scroll a whole screen now preserve the screen
3745position of the cursor, if scroll-preserve-screen-position is non-nil.
3746
3747In this mode, if you scroll several screens back and forth, finishing
3748on the same screen where you started, the cursor goes back to the line
3749where it started.
3750
3751*** If you set scroll-conservatively to a small number, then when you
3752move point a short distance off the screen, Emacs will scroll the
3753screen just far enough to bring point back on screen, provided that
3754does not exceed `scroll-conservatively' lines.
3755
3756*** The new variable scroll-margin says how close point can come to the
3757top or bottom of a window. It is a number of screen lines; if point
3758comes within that many lines of the top or bottom of the window, Emacs
3759recenters the window.
3760
3761** International character set support (MULE)
3762
3763Emacs now supports a wide variety of international character sets,
3764including European variants of the Latin alphabet, as well as Chinese,
3765Devanagari (Hindi and Marathi), Ethiopian, Greek, IPA, Japanese,
3766Korean, Lao, Russian, Thai, Tibetan, and Vietnamese scripts. These
3767features have been merged from the modified version of Emacs known as
3768MULE (for "MULti-lingual Enhancement to GNU Emacs")
3769
3770Users of these scripts have established many more-or-less standard
3771coding systems for storing files. Emacs uses a single multibyte
3772character encoding within Emacs buffers; it can translate from a wide
3773variety of coding systems when reading a file and can translate back
3774into any of these coding systems when saving a file.
3775
3776Keyboards, even in the countries where these character sets are used,
3777generally don't have keys for all the characters in them. So Emacs
3778supports various "input methods", typically one for each script or
3779language, to make it possible to type them.
3780
3781The Emacs internal multibyte encoding represents a non-ASCII
3782character as a sequence of bytes in the range 0200 through 0377.
3783
3784The new prefix key C-x RET is used for commands that pertain
3785to multibyte characters, coding systems, and input methods.
3786
3787You can disable multibyte character support as follows:
3788
3789 (setq-default enable-multibyte-characters nil)
3790
3791Calling the function standard-display-european turns off multibyte
3792characters, unless you specify a non-nil value for the second
3793argument, AUTO. This provides compatibility for people who are
3794already using standard-display-european to continue using unibyte
3795characters for their work until they want to change.
3796
3797*** Input methods
3798
3799An input method is a kind of character conversion which is designed
3800specifically for interactive input. In Emacs, typically each language
3801has its own input method (though sometimes several languages which use
3802the same characters can share one input method). Some languages
3803support several input methods.
3804
3805The simplest kind of input method works by mapping ASCII letters into
3806another alphabet. This is how the Greek and Russian input methods
3807work.
3808
3809A more powerful technique is composition: converting sequences of
3810characters into one letter. Many European input methods use
3811composition to produce a single non-ASCII letter from a sequence which
3812consists of a letter followed by diacritics. For example, a' is one
3813sequence of two characters that might be converted into a single
3814letter.
3815
3816The input methods for syllabic scripts typically use mapping followed
3817by conversion. The input methods for Thai and Korean work this way.
3818First, letters are mapped into symbols for particular sounds or tone
3819marks; then, sequences of these which make up a whole syllable are
3820mapped into one syllable sign--most often a "composite character".
3821
3822None of these methods works very well for Chinese and Japanese, so
3823they are handled specially. First you input a whole word using
3824phonetic spelling; then, after the word is in the buffer, Emacs
3825converts it into one or more characters using a large dictionary.
3826
3827Since there is more than one way to represent a phonetically spelled
3828word using Chinese characters, Emacs can only guess which one to use;
3829typically these input methods give you a way to say "guess again" if
3830the first guess is wrong.
3831
3832*** The command C-x RET m (toggle-enable-multibyte-characters)
3833turns multibyte character support on or off for the current buffer.
3834
3835If multibyte character support is turned off in a buffer, then each
3836byte is a single character, even codes 0200 through 0377--exactly as
3837they did in Emacs 19.34. This includes the features for support for
3838the European characters, ISO Latin-1 and ISO Latin-2.
3839
3840However, there is no need to turn off multibyte character support to
3841use ISO Latin-1 or ISO Latin-2; the Emacs multibyte character set
3842includes all the characters in these character sets, and Emacs can
3843translate automatically to and from either one.
3844
3845*** Visiting a file in unibyte mode.
3846
3847Turning off multibyte character support in the buffer after visiting a
3848file with multibyte code conversion will display the multibyte
3849sequences already in the buffer, byte by byte. This is probably not
3850what you want.
3851
3852If you want to edit a file of unibyte characters (Latin-1, for
3853example), you can do it by specifying `no-conversion' as the coding
3854system when reading the file. This coding system also turns off
3855multibyte characters in that buffer.
3856
3857If you turn off multibyte character support entirely, this turns off
3858character conversion as well.
3859
3860*** Displaying international characters on X Windows.
3861
3862A font for X typically displays just one alphabet or script.
3863Therefore, displaying the entire range of characters Emacs supports
3864requires using many fonts.
3865
3866Therefore, Emacs now supports "fontsets". Each fontset is a
3867collection of fonts, each assigned to a range of character codes.
3868
3869A fontset has a name, like a font. Individual fonts are defined by
3870the X server; fontsets are defined within Emacs itself. But once you
3871have defined a fontset, you can use it in a face or a frame just as
3872you would use a font.
3873
3874If a fontset specifies no font for a certain character, or if it
3875specifies a font that does not exist on your system, then it cannot
3876display that character. It will display an empty box instead.
3877
3878The fontset height and width are determined by the ASCII characters
3879(that is, by the font in the fontset which is used for ASCII
3880characters). If another font in the fontset has a different height,
3881or the wrong width, then characters assigned to that font are clipped,
3882and displayed within a box if highlight-wrong-size-font is non-nil.
3883
3884*** Defining fontsets.
3885
3886Emacs does not use any fontset by default. Its default font is still
3887chosen as in previous versions. You can tell Emacs to use a fontset
3888with the `-fn' option or the `Font' X resource.
3889
3890Emacs creates a standard fontset automatically according to the value
3891of standard-fontset-spec. This fontset's short name is
3892`fontset-standard'. Bold, italic, and bold-italic variants of the
3893standard fontset are created automatically.
3894
3895If you specify a default ASCII font with the `Font' resource or `-fn'
3896argument, a fontset is generated from it. This works by replacing the
3897FOUNDARY, FAMILY, ADD_STYLE, and AVERAGE_WIDTH fields of the font name
3898with `*' then using this to specify a fontset. This fontset's short
3899name is `fontset-startup'.
3900
3901Emacs checks resources of the form Fontset-N where N is 0, 1, 2...
3902The resource value should have this form:
3903 FONTSET-NAME, [CHARSET-NAME:FONT-NAME]...
3904FONTSET-NAME should have the form of a standard X font name, except:
3905 * most fields should be just the wild card "*".
3906 * the CHARSET_REGISTRY field should be "fontset"
3907 * the CHARSET_ENCODING field can be any nickname of the fontset.
3908The construct CHARSET-NAME:FONT-NAME can be repeated any number
3909of times; each time specifies the font for one character set.
3910CHARSET-NAME should be the name name of a character set, and
3911FONT-NAME should specify an actual font to use for that character set.
3912
3913Each of these fontsets has an alias which is made from the
3914last two font name fields, CHARSET_REGISTRY and CHARSET_ENCODING.
3915You can refer to the fontset by that alias or by its full name.
3916
3917For any character sets that you don't mention, Emacs tries to choose a
3918font by substituting into FONTSET-NAME. For instance, with the
3919following resource,
3920 Emacs*Fontset-0: -*-fixed-medium-r-normal-*-24-*-*-*-*-*-fontset-24
3921the font for ASCII is generated as below:
3922 -*-fixed-medium-r-normal-*-24-*-ISO8859-1
3923Here is the substitution rule:
3924 Change CHARSET_REGISTRY and CHARSET_ENCODING to that of the charset
3925 defined in the variable x-charset-registries. For instance, ASCII has
3926 the entry (ascii . "ISO8859-1") in this variable. Then, reduce
3927 sequences of wild cards -*-...-*- with a single wildcard -*-.
3928 (This is to prevent use of auto-scaled fonts.)
3929
3930The function which processes the fontset resource value to create the
3931fontset is called create-fontset-from-fontset-spec. You can also call
3932that function explicitly to create a fontset.
3933
3934With the X resource Emacs.Font, you can specify a fontset name just
3935like an actual font name. But be careful not to specify a fontset
3936name in a wildcard resource like Emacs*Font--that tries to specify the
3937fontset for other purposes including menus, and they cannot handle
3938fontsets.
3939
3940*** The command M-x set-language-environment sets certain global Emacs
3941defaults for a particular choice of language.
3942
3943Selecting a language environment typically specifies a default input
3944method and which coding systems to recognize automatically when
3945visiting files. However, it does not try to reread files you have
3946already visited; the text in those buffers is not affected. The
3947language environment may also specify a default choice of coding
3948system for new files that you create.
3949
3950It makes no difference which buffer is current when you use
3951set-language-environment, because these defaults apply globally to the
3952whole Emacs session.
3953
3954For example, M-x set-language-environment RET Latin-1 RET
3955chooses the Latin-1 character set. In the .emacs file, you can do this
3956with (set-language-environment "Latin-1").
3957
3958*** The command C-x RET f (set-buffer-file-coding-system)
3959specifies the file coding system for the current buffer. This
3960specifies what sort of character code translation to do when saving
3961the file. As an argument, you must specify the name of one of the
3962coding systems that Emacs supports.
3963
3964*** The command C-x RET c (universal-coding-system-argument)
3965lets you specify a coding system when you read or write a file.
3966This command uses the minibuffer to read a coding system name.
3967After you exit the minibuffer, the specified coding system
3968is used for *the immediately following command*.
3969
3970So if the immediately following command is a command to read or
3971write a file, it uses the specified coding system for that file.
3972
3973If the immediately following command does not use the coding system,
3974then C-x RET c ultimately has no effect.
3975
3976For example, C-x RET c iso-8859-1 RET C-x C-f temp RET
3977visits the file `temp' treating it as ISO Latin-1.
3978
3979*** You can specify the coding system for a file using the -*-
3980construct. Include `coding: CODINGSYSTEM;' inside the -*-...-*-
3981to specify use of coding system CODINGSYSTEM. You can also
3982specify the coding system in a local variable list at the end
3983of the file.
3984
3985*** The command C-x RET t (set-terminal-coding-system) specifies
3986the coding system for terminal output. If you specify a character
3987code for terminal output, all characters output to the terminal are
3988translated into that character code.
3989
3990This feature is useful for certain character-only terminals built in
3991various countries to support the languages of those countries.
3992
3993By default, output to the terminal is not translated at all.
3994
3995*** The command C-x RET k (set-keyboard-coding-system) specifies
3996the coding system for keyboard input.
3997
3998Character code translation of keyboard input is useful for terminals
3999with keys that send non-ASCII graphic characters--for example,
4000some terminals designed for ISO Latin-1 or subsets of it.
4001
4002By default, keyboard input is not translated at all.
4003
4004Character code translation of keyboard input is similar to using an
4005input method, in that both define sequences of keyboard input that
4006translate into single characters. However, input methods are designed
4007to be convenient for interactive use, while the code translations are
4008designed to work with terminals.
4009
4010*** The command C-x RET p (set-buffer-process-coding-system)
4011specifies the coding system for input and output to a subprocess.
4012This command applies to the current buffer; normally, each subprocess
4013has its own buffer, and thus you can use this command to specify
4014translation to and from a particular subprocess by giving the command
4015in the corresponding buffer.
4016
4017By default, process input and output are not translated at all.
4018
4019*** The variable file-name-coding-system specifies the coding system
4020to use for encoding file names before operating on them.
4021It is also used for decoding file names obtained from the system.
4022
4023*** The command C-\ (toggle-input-method) activates or deactivates
4024an input method. If no input method has been selected before, the
4025command prompts for you to specify the language and input method you
4026want to use.
4027
4028C-u C-\ (select-input-method) lets you switch to a different input
4029method. C-h C-\ (or C-h I) describes the current input method.
4030
4031*** Some input methods remap the keyboard to emulate various keyboard
4032layouts commonly used for particular scripts. How to do this
4033remapping properly depends on your actual keyboard layout. To specify
4034which layout your keyboard has, use M-x quail-set-keyboard-layout.
4035
4036*** The command C-h C (describe-coding-system) displays
4037the coding systems currently selected for various purposes, plus
4038related information.
4039
4040*** The command C-h h (view-hello-file) displays a file called
4041HELLO, which has examples of text in many languages, using various
4042scripts.
4043
4044*** The command C-h L (describe-language-support) displays
4045information about the support for a particular language.
4046You specify the language as an argument.
4047
4048*** The mode line now contains a letter or character that identifies
4049the coding system used in the visited file. It normally follows the
4050first dash.
4051
4052A dash indicates the default state of affairs: no code conversion
4053(except CRLF => newline if appropriate). `=' means no conversion
4054whatsoever. The ISO 8859 coding systems are represented by digits
40551 through 9. Other coding systems are represented by letters:
4056
4057 A alternativnyj (Russian)
4058 B big5 (Chinese)
4059 C cn-gb-2312 (Chinese)
4060 C iso-2022-cn (Chinese)
4061 D in-is13194-devanagari (Indian languages)
4062 E euc-japan (Japanese)
4063 I iso-2022-cjk or iso-2022-ss2 (Chinese, Japanese, Korean)
4064 J junet (iso-2022-7) or old-jis (iso-2022-jp-1978-irv) (Japanese)
4065 K euc-korea (Korean)
4066 R koi8 (Russian)
4067 Q tibetan
4068 S shift_jis (Japanese)
4069 T lao
4070 T tis620 (Thai)
4071 V viscii or vscii (Vietnamese)
4072 i iso-2022-lock (Chinese, Japanese, Korean)
4073 k iso-2022-kr (Korean)
4074 v viqr (Vietnamese)
4075 z hz (Chinese)
4076
4077When you are using a character-only terminal (not a window system),
4078two additional characters appear in between the dash and the file
4079coding system. These two characters describe the coding system for
4080keyboard input, and the coding system for terminal output.
4081
4082*** The new variable rmail-file-coding-system specifies the code
4083conversion to use for RMAIL files. The default value is nil.
4084
4085When you read mail with Rmail, each message is decoded automatically
4086into Emacs' internal format. This has nothing to do with
4087rmail-file-coding-system. That variable controls reading and writing
4088Rmail files themselves.
4089
4090*** The new variable sendmail-coding-system specifies the code
4091conversion for outgoing mail. The default value is nil.
4092
4093Actually, there are three different ways of specifying the coding system
4094for sending mail:
4095
4096- If you use C-x RET f in the mail buffer, that takes priority.
4097- Otherwise, if you set sendmail-coding-system non-nil, that specifies it.
4098- Otherwise, the default coding system for new files is used,
4099 if that is non-nil. That comes from your language environment.
4100- Otherwise, Latin-1 is used.
4101
4102*** The command C-h t (help-with-tutorial) accepts a prefix argument
4103to specify the language for the tutorial file. Currently, English,
4104Japanese, Korean and Thai are supported. We welcome additional
4105translations.
4106
4107** An easy new way to visit a file with no code or format conversion
4108of any kind: Use M-x find-file-literally. There is also a command
4109insert-file-literally which inserts a file into the current buffer
4110without any conversion.
4111
4112** C-q's handling of octal character codes is changed.
4113You can now specify any number of octal digits.
4114RET terminates the digits and is discarded;
4115any other non-digit terminates the digits and is then used as input.
4116
4117** There are new commands for looking up Info documentation for
4118functions, variables and file names used in your programs.
4119
4120Type M-x info-lookup-symbol to look up a symbol in the buffer at point.
4121Type M-x info-lookup-file to look up a file in the buffer at point.
4122
4123Precisely which Info files are used to look it up depends on the major
4124mode. For example, in C mode, the GNU libc manual is used.
4125
4126** M-TAB in most programming language modes now runs the command
4127complete-symbol. This command performs completion on the symbol name
4128in the buffer before point.
4129
4130With a numeric argument, it performs completion based on the set of
4131symbols documented in the Info files for the programming language that
4132you are using.
4133
4134With no argument, it does completion based on the current tags tables,
4135just like the old binding of M-TAB (complete-tag).
4136
4137** File locking works with NFS now.
4138
4139The lock file for FILENAME is now a symbolic link named .#FILENAME,
4140in the same directory as FILENAME.
4141
4142This means that collision detection between two different machines now
4143works reasonably well; it also means that no file server or directory
4144can become a bottleneck.
4145
4146The new method does have drawbacks. It means that collision detection
4147does not operate when you edit a file in a directory where you cannot
4148create new files. Collision detection also doesn't operate when the
4149file server does not support symbolic links. But these conditions are
4150rare, and the ability to have collision detection while using NFS is
4151so useful that the change is worth while.
4152
4153When Emacs or a system crashes, this may leave behind lock files which
4154are stale. So you may occasionally get warnings about spurious
4155collisions. When you determine that the collision is spurious, just
4156tell Emacs to go ahead anyway.
4157
4158** If you wish to use Show Paren mode to display matching parentheses,
4159it is no longer sufficient to load paren.el. Instead you must call
4160show-paren-mode.
4161
4162** If you wish to use Delete Selection mode to replace a highlighted
4163selection when you insert new text, it is no longer sufficient to load
4164delsel.el. Instead you must call the function delete-selection-mode.
4165
4166** If you wish to use Partial Completion mode to complete partial words
4167within symbols or filenames, it is no longer sufficient to load
4168complete.el. Instead you must call the function partial-completion-mode.
4169
4170** If you wish to use uniquify to rename buffers for you,
4171it is no longer sufficient to load uniquify.el. You must also
4172set uniquify-buffer-name-style to one of the non-nil legitimate values.
4173
4174** Changes in View mode.
4175
4176*** Several new commands are available in View mode.
4177Do H in view mode for a list of commands.
4178
4179*** There are two new commands for entering View mode:
4180view-file-other-frame and view-buffer-other-frame.
4181
4182*** Exiting View mode does a better job of restoring windows to their
4183previous state.
4184
4185*** New customization variable view-scroll-auto-exit. If non-nil,
4186scrolling past end of buffer makes view mode exit.
4187
4188*** New customization variable view-exits-all-viewing-windows. If
4189non-nil, view-mode will at exit restore all windows viewing buffer,
4190not just the selected window.
4191
4192*** New customization variable view-read-only. If non-nil, visiting a
4193read-only file automatically enters View mode, and toggle-read-only
4194turns View mode on or off.
4195
4196*** New customization variable view-remove-frame-by-deleting controls
4197how to remove a not needed frame at view mode exit. If non-nil,
4198delete the frame, if nil make an icon of it.
4199
4200** C-x v l, the command to print a file's version control log,
4201now positions point at the entry for the file's current branch version.
4202
4203** C-x v =, the command to compare a file with the last checked-in version,
4204has a new feature. If the file is currently not locked, so that it is
4205presumably identical to the last checked-in version, the command now asks
4206which version to compare with.
4207
4208** When using hideshow.el, incremental search can temporarily show hidden
4209blocks if a match is inside the block.
4210
4211The block is hidden again if the search is continued and the next match
4212is outside the block. By customizing the variable
4213isearch-hide-immediately you can choose to hide all the temporarily
4214shown blocks only when exiting from incremental search.
4215
4216By customizing the variable hs-isearch-open you can choose what kind
4217of blocks to temporarily show during isearch: comment blocks, code
4218blocks, all of them or none.
4219
4220** The new command C-x 4 0 (kill-buffer-and-window) kills the
4221current buffer and deletes the selected window. It asks for
4222confirmation first.
4223
4224** C-x C-w, which saves the buffer into a specified file name,
4225now changes the major mode according to that file name.
4226However, the mode will not be changed if
4227(1) a local variables list or the `-*-' line specifies a major mode, or
4228(2) the current major mode is a "special" mode,
4229 not suitable for ordinary files, or
4230(3) the new file name does not particularly specify any mode.
4231
4232This applies to M-x set-visited-file-name as well.
4233
4234However, if you set change-major-mode-with-file-name to nil, then
4235these commands do not change the major mode.
4236
4237** M-x occur changes.
4238
4239*** If the argument to M-x occur contains upper case letters,
4240it performs a case-sensitive search.
4241
4242*** In the *Occur* buffer made by M-x occur,
4243if you type g or M-x revert-buffer, this repeats the search
4244using the same regular expression and the same buffer as before.
4245
4246** In Transient Mark mode, the region in any one buffer is highlighted
4247in just one window at a time. At first, it is highlighted in the
4248window where you set the mark. The buffer's highlighting remains in
4249that window unless you select to another window which shows the same
4250buffer--then the highlighting moves to that window.
4251
4252** The feature to suggest key bindings when you use M-x now operates
4253after the command finishes. The message suggesting key bindings
4254appears temporarily in the echo area. The previous echo area contents
4255come back after a few seconds, in case they contain useful information.
4256
4257** Each frame now independently records the order for recently
4258selected buffers, so that the default for C-x b is now based on the
4259buffers recently selected in the selected frame.
4260
4261** Outline mode changes.
4262
4263*** Outline mode now uses overlays (this is the former noutline.el).
4264
4265*** Incremental searches skip over invisible text in Outline mode.
4266
4267** When a minibuffer window is active but not the selected window, if
4268you try to use the minibuffer, you used to get a nested minibuffer.
4269Now, this not only gives an error, it also cancels the minibuffer that
4270was already active.
4271
4272The motive for this change is so that beginning users do not
4273unknowingly move away from minibuffers, leaving them active, and then
4274get confused by it.
4275
4276If you want to be able to have recursive minibuffers, you must
4277set enable-recursive-minibuffers to non-nil.
4278
4279** Changes in dynamic abbrevs.
4280
4281*** Expanding dynamic abbrevs with M-/ is now smarter about case
4282conversion. If the expansion has mixed case not counting the first
4283character, and the abbreviation matches the beginning of the expansion
4284including case, then the expansion is copied verbatim.
4285
4286The expansion is also copied verbatim if the abbreviation itself has
4287mixed case. And using SPC M-/ to copy an additional word always
4288copies it verbatim except when the previous copied word is all caps.
4289
4290*** The values of `dabbrev-case-replace' and `dabbrev-case-fold-search'
4291are no longer Lisp expressions. They have simply three possible
4292values.
4293
4294`dabbrev-case-replace' has these three values: nil (don't preserve
4295case), t (do), or `case-replace' (do like M-x query-replace).
4296`dabbrev-case-fold-search' has these three values: nil (don't ignore
4297case), t (do), or `case-fold-search' (do like search).
4298
4299** Minibuffer history lists are truncated automatically now to a
4300certain length. The variable history-length specifies how long they
4301can be. The default value is 30.
4302
4303** Changes in Mail mode.
4304
4305*** The key C-x m no longer runs the `mail' command directly.
4306Instead, it runs the command `compose-mail', which invokes the mail
4307composition mechanism you have selected with the variable
4308`mail-user-agent'. The default choice of user agent is
4309`sendmail-user-agent', which gives behavior compatible with the old
4310behavior.
4311
4312C-x 4 m now runs compose-mail-other-window, and C-x 5 m runs
4313compose-mail-other-frame.
4314
4315*** While composing a reply to a mail message, from Rmail, you can use
4316the command C-c C-r to cite just the region from the message you are
4317replying to. This copies the text which is the selected region in the
4318buffer that shows the original message.
4319
4320*** The command C-c C-i inserts a file at the end of the message,
4321with separator lines around the contents.
4322
4323*** The command M-x expand-mail-aliases expands all mail aliases
4324in suitable mail headers. Emacs automatically extracts mail alias
4325definitions from your mail alias file (e.g., ~/.mailrc). You do not
4326need to expand mail aliases yourself before sending mail.
4327
4328*** New features in the mail-complete command.
4329
4330**** The mail-complete command now inserts the user's full name,
4331for local users or if that is known. The variable mail-complete-style
4332controls the style to use, and whether to do this at all.
4333Its values are like those of mail-from-style.
4334
4335**** The variable mail-passwd-command lets you specify a shell command
4336to run to fetch a set of password-entries that add to the ones in
4337/etc/passwd.
4338
4339**** The variable mail-passwd-file now specifies a list of files to read
4340to get the list of user ids. By default, one file is used:
4341/etc/passwd.
4342
4343** You can "quote" a file name to inhibit special significance of
4344special syntax, by adding `/:' to the beginning. Thus, if you have a
4345directory named `/foo:', you can prevent it from being treated as a
4346reference to a remote host named `foo' by writing it as `/:/foo:'.
4347
4348Emacs uses this new construct automatically when necessary, such as
4349when you start it with a working directory whose name might otherwise
4350be taken to be magic.
4351
4352** There is a new command M-x grep-find which uses find to select
4353files to search through, and grep to scan them. The output is
4354available in a Compile mode buffer, as with M-x grep.
4355
4356M-x grep now uses the -e option if the grep program supports that.
4357(-e prevents problems if the search pattern starts with a dash.)
4358
4359** In Dired, the & command now flags for deletion the files whose names
4360suggest they are probably not needed in the long run.
4361
4362In Dired, * is now a prefix key for mark-related commands.
4363
4364new key dired.el binding old key
4365------- ---------------- -------
4366 * c dired-change-marks c
4367 * m dired-mark m
4368 * * dired-mark-executables * (binding deleted)
4369 * / dired-mark-directories / (binding deleted)
4370 * @ dired-mark-symlinks @ (binding deleted)
4371 * u dired-unmark u
4372 * DEL dired-unmark-backward DEL
4373 * ? dired-unmark-all-files M-C-?
4374 * ! dired-unmark-all-marks
4375 * % dired-mark-files-regexp % m
4376 * C-n dired-next-marked-file M-}
4377 * C-p dired-prev-marked-file M-{
4378
4379** Rmail changes.
4380
4381*** When Rmail cannot convert your incoming mail into Babyl format, it
4382saves the new mail in the file RMAILOSE.n, where n is an integer
4383chosen to make a unique name. This way, Rmail will not keep crashing
4384each time you run it.
4385
4386*** In Rmail, the variable rmail-summary-line-count-flag now controls
4387whether to include the line count in the summary. Non-nil means yes.
4388
4389*** In Rmail summary buffers, d and C-d (the commands to delete
4390messages) now take repeat counts as arguments. A negative argument
4391means to move in the opposite direction.
4392
4393*** In Rmail, the t command now takes an optional argument which lets
4394you specify whether to show the message headers in full or pruned.
4395
4396*** In Rmail, the new command w (rmail-output-body-to-file) writes
4397just the body of the current message into a file, without the headers.
4398It takes the file name from the message subject, by default, but you
4399can edit that file name in the minibuffer before it is actually used
4400for output.
4401
4402** Gnus changes.
4403
4404*** nntp.el has been totally rewritten in an asynchronous fashion.
4405
4406*** Article prefetching functionality has been moved up into
4407Gnus.
4408
4409*** Scoring can now be performed with logical operators like
4410`and', `or', `not', and parent redirection.
4411
4412*** Article washing status can be displayed in the
4413article mode line.
4414
4415*** gnus.el has been split into many smaller files.
4416
4417*** Suppression of duplicate articles based on Message-ID.
4418
4419(setq gnus-suppress-duplicates t)
4420
4421*** New variables for specifying what score and adapt files
4422are to be considered home score and adapt files. See
4423`gnus-home-score-file' and `gnus-home-adapt-files'.
4424
4425*** Groups can inherit group parameters from parent topics.
4426
4427*** Article editing has been revamped and is now usable.
4428
4429*** Signatures can be recognized in more intelligent fashions.
4430See `gnus-signature-separator' and `gnus-signature-limit'.
4431
4432*** Summary pick mode has been made to look more nn-like.
4433Line numbers are displayed and the `.' command can be
4434used to pick articles.
4435
4436*** Commands for moving the .newsrc.eld from one server to
4437another have been added.
4438
4439 `M-x gnus-change-server'
4440
4441*** A way to specify that "uninteresting" fields be suppressed when
4442generating lines in buffers.
4443
4444*** Several commands in the group buffer can be undone with
4445`M-C-_'.
4446
4447*** Scoring can be done on words using the new score type `w'.
4448
4449*** Adaptive scoring can be done on a Subject word-by-word basis:
4450
4451 (setq gnus-use-adaptive-scoring '(word))
4452
4453*** Scores can be decayed.
4454
4455 (setq gnus-decay-scores t)
4456
4457*** Scoring can be performed using a regexp on the Date header. The
4458Date is normalized to compact ISO 8601 format first.
4459
4460*** A new command has been added to remove all data on articles from
4461the native server.
4462
4463 `M-x gnus-group-clear-data-on-native-groups'
4464
4465*** A new command for reading collections of documents
4466(nndoc with nnvirtual on top) has been added -- `M-C-d'.
4467
4468*** Process mark sets can be pushed and popped.
4469
4470*** A new mail-to-news backend makes it possible to post
4471even when the NNTP server doesn't allow posting.
4472
4473*** A new backend for reading searches from Web search engines
4474(DejaNews, Alta Vista, InReference) has been added.
4475
4476 Use the `G w' command in the group buffer to create such
4477 a group.
4478
4479*** Groups inside topics can now be sorted using the standard
4480sorting functions, and each topic can be sorted independently.
4481
4482 See the commands under the `T S' submap.
4483
4484*** Subsets of the groups can be sorted independently.
4485
4486 See the commands under the `G P' submap.
4487
4488*** Cached articles can be pulled into the groups.
4489
4490 Use the `Y c' command.
4491
4492*** Score files are now applied in a more reliable order.
4493
4494*** Reports on where mail messages end up can be generated.
4495
4496 `M-x nnmail-split-history'
4497
4498*** More hooks and functions have been added to remove junk
4499from incoming mail before saving the mail.
4500
4501 See `nnmail-prepare-incoming-header-hook'.
4502
4503*** The nnml mail backend now understands compressed article files.
4504
4505*** To enable Gnus to read/post multi-lingual articles, you must execute
4506the following code, for instance, in your .emacs.
4507
4508 (add-hook 'gnus-startup-hook 'gnus-mule-initialize)
4509
4510Then, when you start Gnus, it will decode non-ASCII text automatically
4511and show appropriate characters. (Note: if you are using gnus-mime
4512from the SEMI package, formerly known as TM, you should NOT add this
4513hook to gnus-startup-hook; gnus-mime has its own method of handling
4514this issue.)
4515
4516Since it is impossible to distinguish all coding systems
4517automatically, you may need to specify a choice of coding system for a
4518particular news group. This can be done by:
4519
4520 (gnus-mule-add-group NEWSGROUP 'CODING-SYSTEM)
4521
4522Here NEWSGROUP should be a string which names a newsgroup or a tree
4523of newsgroups. If NEWSGROUP is "XXX.YYY", all news groups under
4524"XXX.YYY" (including "XXX.YYY.ZZZ") will use the specified coding
4525system. CODING-SYSTEM specifies which coding system to use (for both
4526for reading and posting).
4527
4528CODING-SYSTEM can also be a cons cell of the form
4529 (READ-CODING-SYSTEM . POST-CODING-SYSTEM)
4530Then READ-CODING-SYSTEM is used when you read messages from the
4531newsgroups, while POST-CODING-SYSTEM is used when you post messages
4532there.
4533
4534Emacs knows the right coding systems for certain newsgroups by
4535default. Here are some of these default settings:
4536
4537 (gnus-mule-add-group "fj" 'iso-2022-7)
4538 (gnus-mule-add-group "alt.chinese.text" 'hz-gb-2312)
4539 (gnus-mule-add-group "alt.hk" 'hz-gb-2312)
4540 (gnus-mule-add-group "alt.chinese.text.big5" 'cn-big5)
4541 (gnus-mule-add-group "soc.culture.vietnamese" '(nil . viqr))
4542
4543When you reply by mail to an article, these settings are ignored;
4544the mail is encoded according to sendmail-coding-system, as usual.
4545
4546** CC mode changes.
4547
4548*** If you edit primarily one style of C (or C++, Objective-C, Java)
4549code, you may want to make the CC Mode style variables have global
4550values so that you can set them directly in your .emacs file. To do
4551this, set c-style-variables-are-local-p to nil in your .emacs file.
4552Note that this only takes effect if you do it *before* cc-mode.el is
4553loaded.
4554
4555If you typically edit more than one style of C (or C++, Objective-C,
4556Java) code in a single Emacs session, you may want to make the CC Mode
4557style variables have buffer local values. By default, all buffers
4558share the same style variable settings; to make them buffer local, set
4559c-style-variables-are-local-p to t in your .emacs file. Note that you
4560must do this *before* CC Mode is loaded.
4561
4562*** The new variable c-indentation-style holds the C style name
4563of the current buffer.
4564
4565*** The variable c-block-comments-indent-p has been deleted, because
4566it is no longer necessary. C mode now handles all the supported styles
4567of block comments, with no need to say which one you will use.
4568
4569*** There is a new indentation style "python", which specifies the C
4570style that the Python developers like.
4571
4572*** There is a new c-cleanup-list option: brace-elseif-brace.
4573This says to put ...} else if (...) {... on one line,
4574just as brace-else-brace says to put ...} else {... on one line.
4575
4576** VC Changes [new]
4577
4578** In vc-retrieve-snapshot (C-x v r), if you don't specify a snapshot
4579name, it retrieves the *latest* versions of all files in the current
4580directory and its subdirectories (aside from files already locked).
4581
4582This feature is useful if your RCS directory is a link to a common
4583master directory, and you want to pick up changes made by other
4584developers.
4585
4586You can do the same thing for an individual file by typing C-u C-x C-q
4587RET in a buffer visiting that file.
4588
4589*** VC can now handle files under CVS that are being "watched" by
4590other developers. Such files are made read-only by CVS. To get a
4591writable copy, type C-x C-q in a buffer visiting such a file. VC then
4592calls "cvs edit", which notifies the other developers of it.
4593
4594*** vc-version-diff (C-u C-x v =) now suggests reasonable defaults for
4595version numbers, based on the current state of the file.
4596
4597** Calendar changes.
4598
4599A new function, list-holidays, allows you list holidays or subclasses
4600of holidays for ranges of years. Related menu items allow you do this
4601for the year of the selected date, or the following/previous years.
4602
4603** ps-print changes
4604
4605There are some new user variables for customizing the page layout.
4606
4607*** Paper size, paper orientation, columns
4608
4609The variable `ps-paper-type' determines the size of paper ps-print
4610formats for; it should contain one of the symbols:
4611`a4' `a3' `letter' `legal' `letter-small' `tabloid'
4612`ledger' `statement' `executive' `a4small' `b4' `b5'
4613It defaults to `letter'.
4614If you need other sizes, see the variable `ps-page-dimensions-database'.
4615
4616The variable `ps-landscape-mode' determines the orientation
4617of the printing on the page. nil, the default, means "portrait" mode,
4618non-nil means "landscape" mode.
4619
4620The variable `ps-number-of-columns' must be a positive integer.
4621It determines the number of columns both in landscape and portrait mode.
4622It defaults to 1.
4623
4624*** Horizontal layout
4625
4626The horizontal layout is determined by the variables
4627`ps-left-margin', `ps-inter-column', and `ps-right-margin'.
4628All are measured in points.
4629
4630*** Vertical layout
4631
4632The vertical layout is determined by the variables
4633`ps-bottom-margin', `ps-top-margin', and `ps-header-offset'.
4634All are measured in points.
4635
4636*** Headers
4637
4638If the variable `ps-print-header' is nil, no header is printed. Then
4639`ps-header-offset' is not relevant and `ps-top-margin' represents the
4640margin above the text.
4641
4642If the variable `ps-print-header-frame' is non-nil, a gaudy
4643framing box is printed around the header.
4644
4645The contents of the header are determined by `ps-header-lines',
4646`ps-show-n-of-n', `ps-left-header' and `ps-right-header'.
4647
4648The height of the header is determined by `ps-header-line-pad',
4649`ps-header-font-family', `ps-header-title-font-size' and
4650`ps-header-font-size'.
4651
4652*** Font managing
4653
4654The variable `ps-font-family' determines which font family is to be
4655used for ordinary text. Its value must be a key symbol in the alist
4656`ps-font-info-database'. You can add other font families by adding
4657elements to this alist.
4658
4659The variable `ps-font-size' determines the size of the font
4660for ordinary text. It defaults to 8.5 points.
4661
4662** hideshow changes.
4663
4664*** now supports hiding of blocks of single line comments (like // for
4665C++, ; for lisp).
4666
4667*** Support for java-mode added.
4668
4669*** When doing `hs-hide-all' it is now possible to also hide the comments
4670in the file if `hs-hide-comments-when-hiding-all' is set.
4671
4672*** The new function `hs-hide-initial-comment' hides the the comments at
4673the beginning of the files. Finally those huge RCS logs don't stay in your
4674way! This is run by default when entering the `hs-minor-mode'.
4675
4676*** Now uses overlays instead of `selective-display', so is more
4677robust and a lot faster.
4678
4679*** A block beginning can span multiple lines.
4680
4681*** The new variable `hs-show-hidden-short-form' if t, directs hideshow
4682to show only the beginning of a block when it is hidden. See the
4683documentation for more details.
4684
4685** Changes in Enriched mode.
4686
4687*** When you visit a file in enriched-mode, Emacs will make sure it is
4688filled to the current fill-column. This behavior is now independent
4689of the size of the window. When you save the file, the fill-column in
4690use is stored as well, so that the whole buffer need not be refilled
4691the next time unless the fill-column is different.
4692
4693*** use-hard-newlines is now a minor mode. When it is enabled, Emacs
4694distinguishes between hard and soft newlines, and treats hard newlines
4695as paragraph boundaries. Otherwise all newlines inserted are marked
4696as soft, and paragraph boundaries are determined solely from the text.
4697
4698** Font Lock mode
4699
4700*** Custom support
4701
4702The variables font-lock-face-attributes, font-lock-display-type and
4703font-lock-background-mode are now obsolete; the recommended way to specify the
4704faces to use for Font Lock mode is with M-x customize-group on the new custom
4705group font-lock-highlighting-faces. If you set font-lock-face-attributes in
4706your ~/.emacs file, Font Lock mode will respect its value. However, you should
4707consider converting from setting that variable to using M-x customize.
4708
4709You can still use X resources to specify Font Lock face appearances.
4710
4711*** Maximum decoration
4712
4713Fontification now uses the maximum level of decoration supported by
4714default. Previously, fontification used a mode-specific default level
4715of decoration, which is typically the minimum level of decoration
4716supported. You can set font-lock-maximum-decoration to nil
4717to get the old behavior.
4718
4719*** New support
4720
4721Support is now provided for Java, Objective-C, AWK and SIMULA modes.
4722
4723Note that Font Lock mode can be turned on without knowing exactly what modes
4724support Font Lock mode, via the command global-font-lock-mode.
4725
4726*** Configurable support
4727
4728Support for C, C++, Objective-C and Java can be more easily configured for
4729additional types and classes via the new variables c-font-lock-extra-types,
4730c++-font-lock-extra-types, objc-font-lock-extra-types and, you guessed it,
4731java-font-lock-extra-types. These value of each of these variables should be a
4732list of regexps matching the extra type names. For example, the default value
4733of c-font-lock-extra-types is ("\\sw+_t") which means fontification follows the
4734convention that C type names end in _t. This results in slower fontification.
4735
4736Of course, you can change the variables that specify fontification in whatever
4737way you wish, typically by adding regexps. However, these new variables make
4738it easier to make specific and common changes for the fontification of types.
4739
4740*** Adding highlighting patterns to existing support
4741
4742You can use the new function font-lock-add-keywords to add your own
4743highlighting patterns, such as for project-local or user-specific constructs,
4744for any mode.
4745
4746For example, to highlight `FIXME:' words in C comments, put:
4747
4748 (font-lock-add-keywords 'c-mode '(("\\<FIXME:" 0 font-lock-warning-face t)))
4749
4750in your ~/.emacs.
4751
4752*** New faces
4753
4754Font Lock now defines two new faces, font-lock-builtin-face and
4755font-lock-warning-face. These are intended to highlight builtin keywords,
4756distinct from a language's normal keywords, and objects that should be brought
4757to user attention, respectively. Various modes now use these new faces.
4758
4759*** Changes to fast-lock support mode
4760
4761The fast-lock package, one of the two Font Lock support modes, can now process
4762cache files silently. You can use the new variable fast-lock-verbose, in the
4763same way as font-lock-verbose, to control this feature.
4764
4765*** Changes to lazy-lock support mode
4766
4767The lazy-lock package, one of the two Font Lock support modes, can now fontify
4768according to the true syntactic context relative to other lines. You can use
4769the new variable lazy-lock-defer-contextually to control this feature. If
4770non-nil, changes to the buffer will cause subsequent lines in the buffer to be
4771refontified after lazy-lock-defer-time seconds of idle time. If nil, then only
4772the modified lines will be refontified; this is the same as the previous Lazy
4773Lock mode behaviour and the behaviour of Font Lock mode.
4774
4775This feature is useful in modes where strings or comments can span lines.
4776For example, if a string or comment terminating character is deleted, then if
4777this feature is enabled subsequent lines in the buffer will be correctly
4778refontified to reflect their new syntactic context. Previously, only the line
4779containing the deleted character would be refontified and you would have to use
4780the command M-g M-g (font-lock-fontify-block) to refontify some lines.
4781
4782As a consequence of this new feature, two other variables have changed:
4783
4784Variable `lazy-lock-defer-driven' is renamed `lazy-lock-defer-on-scrolling'.
4785Variable `lazy-lock-defer-time' can now only be a time, i.e., a number.
4786Buffer modes for which on-the-fly deferral applies can be specified via the
4787new variable `lazy-lock-defer-on-the-fly'.
4788
4789If you set these variables in your ~/.emacs, then you may have to change those
4790settings.
4791
4792** Ada mode changes.
4793
4794*** There is now better support for using find-file.el with Ada mode.
4795If you switch between spec and body, the cursor stays in the same
4796procedure (modulo overloading). If a spec has no body file yet, but
4797you try to switch to its body file, Ada mode now generates procedure
4798stubs.
4799
4800*** There are two new commands:
4801 - `ada-make-local' : invokes gnatmake on the current buffer
4802 - `ada-check-syntax' : check syntax of current buffer.
4803
4804The user options `ada-compiler-make', `ada-make-options',
4805`ada-language-version', `ada-compiler-syntax-check', and
4806`ada-compile-options' are used within these commands.
4807
4808*** Ada mode can now work with Outline minor mode. The outline level
4809is calculated from the indenting, not from syntactic constructs.
4810Outlining does not work if your code is not correctly indented.
4811
4812*** The new function `ada-gnat-style' converts the buffer to the style of
4813formatting used in GNAT. It places two blanks after a comment start,
4814places one blank between a word end and an opening '(', and puts one
4815space between a comma and the beginning of a word.
4816
4817** Scheme mode changes.
4818
4819*** Scheme mode indentation now uses many of the facilities of Lisp
4820mode; therefore, the variables to customize it are the variables used
4821for Lisp mode which have names starting with `lisp-'. The variables
4822with names starting with `scheme-' which used to do this no longer
4823have any effect.
4824
4825If you want to use different indentation for Scheme and Lisp, this is
4826still possible, but now you must do it by adding a hook to
4827scheme-mode-hook, which could work by setting the `lisp-' indentation
4828variables as buffer-local variables.
4829
4830*** DSSSL mode is a variant of Scheme mode, for editing DSSSL scripts.
4831Use M-x dsssl-mode.
4832
4833** The emacsclient program now accepts an option --no-wait which tells
4834it to return immediately without waiting for you to "finish" the
4835buffer in Emacs.
4836
4837** M-x eldoc-mode enables a minor mode in which the echo area
4838constantly shows the parameter list for function being called at point
4839(in Emacs Lisp and Lisp Interaction modes only).
4840
4841** C-x n d now runs the new command narrow-to-defun,
4842which narrows the accessible parts of the buffer to just
4843the current defun.
4844
4845** Emacs now handles the `--' argument in the standard way; all
4846following arguments are treated as ordinary file names.
4847
4848** On MSDOS and Windows, the bookmark file is now called _emacs.bmk,
4849and the saved desktop file is now called _emacs.desktop (truncated if
4850necessary).
4851
4852** When you kill a buffer that visits a file,
4853if there are any registers that save positions in the file,
4854these register values no longer become completely useless.
4855If you try to go to such a register with C-x j, then you are
4856asked whether to visit the file again. If you say yes,
4857it visits the file and then goes to the same position.
4858
4859** When you visit a file that changes frequently outside Emacs--for
4860example, a log of output from a process that continues to run--it may
4861be useful for Emacs to revert the file without querying you whenever
4862you visit the file afresh with C-x C-f.
4863
4864You can request this behavior for certain files by setting the
4865variable revert-without-query to a list of regular expressions. If a
4866file's name matches any of these regular expressions, find-file and
4867revert-buffer revert the buffer without asking for permission--but
4868only if you have not edited the buffer text yourself.
4869
4870** set-default-font has been renamed to set-frame-font
4871since it applies only to the current frame.
4872
4873** In TeX mode, you can use the variable tex-main-file to specify the
4874file for tex-file to run TeX on. (By default, tex-main-file is nil,
4875and tex-file runs TeX on the current visited file.)
4876
4877This is useful when you are editing a document that consists of
4878multiple files. In each of the included files, you can set up a local
4879variable list which specifies the top-level file of your document for
4880tex-main-file. Then tex-file will run TeX on the whole document
4881instead of just the file you are editing.
4882
4883** RefTeX mode
4884
4885RefTeX mode is a new minor mode with special support for \label, \ref
4886and \cite macros in LaTeX documents. RefTeX distinguishes labels of
4887different environments (equation, figure, ...) and has full support for
4888multifile documents. To use it, select a buffer with a LaTeX document and
4889turn the mode on with M-x reftex-mode. Here are the main user commands:
4890
4891C-c ( reftex-label
4892 Creates a label semi-automatically. RefTeX is context sensitive and
4893 knows which kind of label is needed.
4894
4895C-c ) reftex-reference
4896 Offers in a menu all labels in the document, along with context of the
4897 label definition. The selected label is referenced as \ref{LABEL}.
4898
4899C-c [ reftex-citation
4900 Prompts for a regular expression and displays a list of matching BibTeX
4901 database entries. The selected entry is cited with a \cite{KEY} macro.
4902
4903C-c & reftex-view-crossref
4904 Views the cross reference of a \ref or \cite command near point.
4905
4906C-c = reftex-toc
4907 Shows a table of contents of the (multifile) document. From there you
4908 can quickly jump to every section.
4909
4910Under X, RefTeX installs a "Ref" menu in the menu bar, with additional
4911commands. Press `?' to get help when a prompt mentions this feature.
4912Full documentation and customization examples are in the file
4913reftex.el. You can use the finder to view the file documentation:
4914C-h p --> tex --> reftex.el
4915
4916** Changes in BibTeX mode.
4917
4918*** Info documentation is now available.
4919
4920*** Don't allow parentheses in string constants anymore. This confused
4921both the BibTeX program and Emacs BibTeX mode.
4922
4923*** Renamed variable bibtex-mode-user-optional-fields to
4924bibtex-user-optional-fields.
4925
4926*** Removed variable bibtex-include-OPTannote
4927(use bibtex-user-optional-fields instead).
4928
4929*** New interactive functions to copy and kill fields and complete
4930entries to the BibTeX kill ring, from where they can be yanked back by
4931appropriate functions.
4932
4933*** New interactive functions for repositioning and marking of
4934entries. They are bound by default to M-C-l and M-C-h.
4935
4936*** New hook bibtex-clean-entry-hook. It is called after entry has
4937been cleaned.
4938
4939*** New variable bibtex-field-delimiters, which replaces variables
4940bibtex-field-{left|right}-delimiter.
4941
4942*** New variable bibtex-entry-delimiters to determine how entries
4943shall be delimited.
4944
4945*** Allow preinitialization of fields. See documentation of
4946bibtex-user-optional-fields, bibtex-entry-field-alist, and
4947bibtex-include-OPTkey for details.
4948
4949*** Book and InBook entries require either an author or an editor
4950field. This is now supported by bibtex.el. Alternative fields are
4951prefixed with `ALT'.
4952
4953*** New variable bibtex-entry-format, which replaces variable
4954bibtex-clean-entry-zap-empty-opts and allows specification of many
4955formatting options performed on cleaning an entry (see variable
4956documentation).
4957
4958*** Even more control on how automatic keys are generated. See
4959documentation of bibtex-generate-autokey for details. Transcriptions
4960for foreign languages other than German are now handled, too.
4961
4962*** New boolean user option bibtex-comma-after-last-field to decide if
4963comma should be inserted at end of last field.
4964
4965*** New boolean user option bibtex-align-at-equal-sign to determine if
4966alignment should be made at left side of field contents or at equal
4967signs. New user options to control entry layout (e.g. indentation).
4968
4969*** New function bibtex-fill-entry to realign entries.
4970
4971*** New function bibtex-reformat to reformat region or buffer.
4972
4973*** New function bibtex-convert-alien to convert a BibTeX database
4974from alien sources.
4975
4976*** New function bibtex-complete-key (similar to bibtex-complete-string)
4977to complete prefix to a key defined in buffer. Mainly useful in
4978crossref entries.
4979
4980*** New function bibtex-count-entries to count entries in buffer or
4981region.
4982
4983*** Added support for imenu.
4984
4985*** The function `bibtex-validate' now checks current region instead
4986of buffer if mark is active. Now it shows all errors of buffer in a
4987`compilation mode' buffer. You can use the normal commands (e.g.
4988`next-error') for compilation modes to jump to errors.
4989
4990*** New variable `bibtex-string-file-path' to determine where the files
4991from `bibtex-string-files' are searched.
4992
4993** Iso Accents mode now supports Latin-3 as an alternative.
4994
4995** The function using-unix-filesystems has been replaced by the
4996functions add-untranslated-filesystem and remove-untranslated-filesystem.
4997Each of these functions takes the name of a drive letter or directory
4998as an argument.
4999
5000When a filesystem is added as untranslated, all files on it are read
5001and written in binary mode (no cr/lf translation is performed).
5002
5003** browse-url changes
5004
5005*** New methods for: Grail (browse-url-generic), MMM (browse-url-mmm),
5006Lynx in a separate xterm (browse-url-lynx-xterm) or in an Emacs window
5007(browse-url-lynx-emacs), remote W3 (browse-url-w3-gnudoit), generic
5008non-remote-controlled browsers (browse-url-generic) and associated
5009customization variables.
5010
5011*** New commands `browse-url-of-region' and `browse-url'.
5012
5013*** URLs marked up with <URL:...> (RFC1738) work if broken across
5014lines. Browsing methods can be associated with URL regexps
5015(e.g. mailto: URLs) via `browse-url-browser-function'.
5016
5017** Changes in Ediff
5018
5019*** Clicking Mouse-2 on a brief command description in Ediff control panel
5020pops up the Info file for this command.
5021
5022*** There is now a variable, ediff-autostore-merges, which controls whether
5023the result of a merge is saved in a file. By default, this is done only when
5024merge is done from a session group (eg, when merging files in two different
5025directories).
5026
5027*** Since Emacs 19.31 (this hasn't been announced before), Ediff can compare
5028and merge groups of files residing in different directories, or revisions of
5029files in the same directory.
5030
5031*** Since Emacs 19.31, Ediff can apply multi-file patches interactively.
5032The patches must be in the context format or GNU unified format. (The bug
5033related to the GNU format has now been fixed.)
5034
5035** Changes in Viper
5036
5037*** The startup file is now .viper instead of .vip
5038*** All variable/function names have been changed to start with viper-
5039 instead of vip-.
5040*** C-\ now simulates the meta-key in all Viper states.
5041*** C-z in Insert state now escapes to Vi for the duration of the next
5042Viper command. In Vi and Insert states, C-z behaves as before.
5043*** C-c \ escapes to Vi for one command if Viper is in Insert or Emacs states.
5044*** _ is no longer the meta-key in Vi state.
5045*** The variable viper-insert-state-cursor-color can be used to change cursor
5046color when Viper is in insert state.
5047*** If search lands the cursor near the top or the bottom of the window,
5048Viper pulls the window up or down to expose more context. The variable
5049viper-adjust-window-after-search controls this behavior.
5050
5051** Etags changes.
5052
5053*** In C, C++, Objective C and Java, Etags tags global variables by
5054default. The resulting tags files are inflated by 30% on average.
5055Use --no-globals to turn this feature off. Etags can also tag
5056variables which are members of structure-like constructs, but it does
5057not by default. Use --members to turn this feature on.
5058
5059*** C++ member functions are now recognized as tags.
5060
5061*** Java is tagged like C++. In addition, "extends" and "implements"
5062constructs are tagged. Files are recognised by the extension .java.
5063
5064*** Etags can now handle programs written in Postscript. Files are
5065recognised by the extensions .ps and .pdb (Postscript with C syntax).
5066In Postscript, tags are lines that start with a slash.
5067
5068*** Etags now handles Objective C and Objective C++ code. The usual C and
5069C++ tags are recognized in these languages; in addition, etags
5070recognizes special Objective C syntax for classes, class categories,
5071methods and protocols.
5072
5073*** Etags also handles Cobol. Files are recognised by the extension
5074.cobol. The tagged lines are those containing a word that begins in
5075column 8 and ends in a full stop, i.e. anything that could be a
5076paragraph name.
5077
5078*** Regexps in Etags now support intervals, as in ed or grep. The syntax of
5079an interval is \{M,N\}, and it means to match the preceding expression
5080at least M times and as many as N times.
5081
5082** The format for specifying a custom format for time-stamp to insert
5083in files has changed slightly.
5084
5085With the new enhancements to the functionality of format-time-string,
5086time-stamp-format will change to be eventually compatible with it.
5087This conversion is being done in two steps to maintain compatibility
5088with old time-stamp-format values.
5089
5090In the new scheme, alternate case is signified by the number-sign
5091(`#') modifier, rather than changing the case of the format character.
5092This feature is as yet incompletely implemented for compatibility
5093reasons.
5094
5095In the old time-stamp-format, all numeric fields defaulted to their
5096natural width. (With format-time-string, each format has a
5097fixed-width default.) In this version, you can specify the colon
5098(`:') modifier to a numeric conversion to mean "give me the historical
5099time-stamp-format width default." Do not use colon if you are
5100specifying an explicit width, as in "%02d".
5101
5102Numbers are no longer truncated to the requested width, except in the
5103case of "%02y", which continues to give a two-digit year. Digit
5104truncation probably wasn't being used for anything else anyway.
5105
5106The new formats will work with old versions of Emacs. New formats are
5107being recommended now to allow time-stamp-format to change in the
5108future to be compatible with format-time-string. The new forms being
5109recommended now will continue to work then.
5110
5111See the documentation string for the variable time-stamp-format for
5112details.
5113
5114** There are some additional major modes:
5115
5116dcl-mode, for editing VMS DCL files.
5117m4-mode, for editing files of m4 input.
5118meta-mode, for editing MetaFont and MetaPost source files.
5119
5120** In Shell mode, the command shell-copy-environment-variable lets you
5121copy the value of a specified environment variable from the subshell
5122into Emacs.
5123
5124** New Lisp packages include:
5125
5126*** battery.el displays battery status for laptops.
5127
5128*** M-x bruce (named after Lenny Bruce) is a program that might
5129be used for adding some indecent words to your email.
5130
5131*** M-x crisp-mode enables an emulation for the CRiSP editor.
5132
5133*** M-x dirtrack arranges for better tracking of directory changes
5134in shell buffers.
5135
5136*** The new library elint.el provides for linting of Emacs Lisp code.
5137See the documentation for `elint-initialize', `elint-current-buffer'
5138and `elint-defun'.
5139
5140*** M-x expand-add-abbrevs defines a special kind of abbrev which is
5141meant for programming constructs. These abbrevs expand like ordinary
5142ones, when you type SPC, but only at the end of a line and not within
5143strings or comments.
5144
5145These abbrevs can act as templates: you can define places within an
5146abbrev for insertion of additional text. Once you expand the abbrev,
5147you can then use C-x a p and C-x a n to move back and forth to these
5148insertion points. Thus you can conveniently insert additional text
5149at these points.
5150
5151*** filecache.el remembers the location of files so that you
5152can visit them by short forms of their names.
5153
5154*** find-func.el lets you find the definition of the user-loaded
5155Emacs Lisp function at point.
5156
5157*** M-x handwrite converts text to a "handwritten" picture.
5158
5159*** M-x iswitchb-buffer is a command for switching to a buffer, much like
5160switch-buffer, but it reads the argument in a more helpful way.
5161
5162*** M-x landmark implements a neural network for landmark learning.
5163
5164*** M-x locate provides a convenient interface to the `locate' program.
5165
5166*** M4 mode is a new mode for editing files of m4 input.
5167
5168*** mantemp.el creates C++ manual template instantiations
5169from the GCC error messages which indicate which instantiations are needed.
5170
5171*** mouse-copy.el provides a one-click copy and move feature.
5172You can drag a region with M-mouse-1, and it is automatically
5173inserted at point. M-Shift-mouse-1 deletes the text from its
5174original place after inserting the copy.
5175
5176*** mouse-drag.el lets you do scrolling by dragging Mouse-2
5177on the buffer.
5178
5179You click the mouse and move; that distance either translates into the
5180velocity to scroll (with mouse-drag-throw) or the distance to scroll
5181(with mouse-drag-drag). Horizontal scrolling is enabled when needed.
5182
5183Enable mouse-drag with:
5184 (global-set-key [down-mouse-2] 'mouse-drag-throw)
5185-or-
5186 (global-set-key [down-mouse-2] 'mouse-drag-drag)
5187
5188*** mspools.el is useful for determining which mail folders have
5189mail waiting to be read in them. It works with procmail.
5190
5191*** Octave mode is a major mode for editing files of input for Octave.
5192It comes with a facility for communicating with an Octave subprocess.
5193
5194*** ogonek
5195
5196The ogonek package provides functions for changing the coding of
5197Polish diacritic characters in buffers. Codings known from various
5198platforms are supported such as ISO8859-2, Mazovia, IBM Latin2, and
5199TeX. For example, you can change the coding from Mazovia to
5200ISO8859-2. Another example is a change of coding from ISO8859-2 to
5201prefix notation (in which `/a' stands for the aogonek character, for
5202instance) and vice versa.
5203
5204To use this package load it using
5205 M-x load-library [enter] ogonek
5206Then, you may get an explanation by calling one of
5207 M-x ogonek-jak -- in Polish
5208 M-x ogonek-how -- in English
5209The info specifies the commands and variables provided as well as the
5210ways of customization in `.emacs'.
5211
5212*** Interface to ph.
5213
5214Emacs provides a client interface to CCSO Nameservers (ph/qi)
5215
5216The CCSO nameserver is used in many universities to provide directory
5217services about people. ph.el provides a convenient Emacs interface to
5218these servers.
5219
5220*** uce.el is useful for replying to unsolicited commercial email.
5221
5222*** vcursor.el implements a "virtual cursor" feature.
5223You can move the virtual cursor with special commands
5224while the real cursor does not move.
5225
5226*** webjump.el is a "hot list" package which you can set up
5227for visiting your favorite web sites.
5228
5229*** M-x winner-mode is a minor mode which saves window configurations,
5230so you can move back to other configurations that you have recently used.
5231
5232** movemail change
5233
5234Movemail no longer needs to be installed setuid root in order for POP
5235mail retrieval to function properly. This is because it no longer
5236supports the RPOP (reserved-port POP) protocol; instead, it uses the
5237user's POP password to authenticate to the mail server.
5238
5239This change was made earlier, but not reported in NEWS before.
5240\f
5241* Emacs 20.1 changes for MS-DOS and MS-Windows.
5242
5243** Changes in handling MS-DOS/MS-Windows text files.
5244
5245Emacs handles three different conventions for representing
5246end-of-line: CRLF for MSDOS, LF for Unix and GNU, and CR (used on the
5247Macintosh). Emacs determines which convention is used in a specific
5248file based on the contents of that file (except for certain special
5249file names), and when it saves the file, it uses the same convention.
5250
5251To save the file and change the end-of-line convention, you can use
5252C-x RET f (set-buffer-file-coding-system) to specify a different
5253coding system for the buffer. Then, when you save the file, the newly
5254specified coding system will take effect. For example, to save with
5255LF, specify undecided-unix (or some other ...-unix coding system); to
5256save with CRLF, specify undecided-dos.
5257\f
5258* Lisp Changes in Emacs 20.1
5259
5260** Byte-compiled files made with Emacs 20 will, in general, work in
5261Emacs 19 as well, as long as the source code runs in Emacs 19. And
5262vice versa: byte-compiled files made with Emacs 19 should also run in
5263Emacs 20, as long as the program itself works in Emacs 20.
5264
5265** Windows-specific functions and variables have been renamed
5266to start with w32- instead of win32-.
5267
5268In hacker language, calling something a "win" is a form of praise. We
5269don't want to praise a non-free Microsoft system, so we don't call it
5270"win".
5271
5272** Basic Lisp changes
5273
5274*** A symbol whose name starts with a colon now automatically
5275evaluates to itself. Therefore such a symbol can be used as a constant.
5276
5277*** The defined purpose of `defconst' has been changed. It should now
5278be used only for values that should not be changed whether by a program
5279or by the user.
5280
5281The actual behavior of defconst has not been changed.
5282
5283*** There are new macros `when' and `unless'
5284
5285(when CONDITION BODY...) is short for (if CONDITION (progn BODY...))
5286(unless CONDITION BODY...) is short for (if CONDITION nil BODY...)
5287
5288*** Emacs now defines functions caar, cadr, cdar and cddr with their
5289usual Lisp meanings. For example, caar returns the car of the car of
5290its argument.
5291
5292*** equal, when comparing strings, now ignores their text properties.
5293
5294*** The new function `functionp' tests whether an object is a function.
5295
5296*** arrayp now returns t for char-tables and bool-vectors.
5297
5298*** Certain primitives which use characters (as integers) now get an
5299error if the integer is not a valid character code. These primitives
5300include insert-char, char-to-string, and the %c construct in the
5301`format' function.
5302
5303*** The `require' function now insists on adding a suffix, either .el
5304or .elc, to the file name. Thus, (require 'foo) will not use a file
5305whose name is just foo. It insists on foo.el or foo.elc.
5306
5307*** The `autoload' function, when the file name does not contain
5308either a directory name or the suffix .el or .elc, insists on
5309adding one of these suffixes.
5310
5311*** string-to-number now takes an optional second argument BASE
5312which specifies the base to use when converting an integer.
5313If BASE is omitted, base 10 is used.
5314
5315We have not implemented other radices for floating point numbers,
5316because that would be much more work and does not seem useful.
5317
5318*** substring now handles vectors as well as strings.
5319
5320*** The Common Lisp function eql is no longer defined normally.
5321You must load the `cl' library to define it.
5322
5323*** The new macro `with-current-buffer' lets you evaluate an expression
5324conveniently with a different current buffer. It looks like this:
5325
5326 (with-current-buffer BUFFER BODY-FORMS...)
5327
5328BUFFER is the expression that says which buffer to use.
5329BODY-FORMS say what to do in that buffer.
5330
5331*** The new primitive `save-current-buffer' saves and restores the
5332choice of current buffer, like `save-excursion', but without saving or
5333restoring the value of point or the mark. `with-current-buffer'
5334works using `save-current-buffer'.
5335
5336*** The new macro `with-temp-file' lets you do some work in a new buffer and
5337write the output to a specified file. Like `progn', it returns the value
5338of the last form.
5339
5340*** The new macro `with-temp-buffer' lets you do some work in a new buffer,
5341which is discarded after use. Like `progn', it returns the value of the
5342last form. If you wish to return the buffer contents, use (buffer-string)
5343as the last form.
5344
5345*** The new function split-string takes a string, splits it at certain
5346characters, and returns a list of the substrings in between the
5347matches.
5348
5349For example, (split-string "foo bar lose" " +") returns ("foo" "bar" "lose").
5350
5351*** The new macro with-output-to-string executes some Lisp expressions
5352with standard-output set up so that all output feeds into a string.
5353Then it returns that string.
5354
5355For example, if the current buffer name is `foo',
5356
5357(with-output-to-string
5358 (princ "The buffer is ")
5359 (princ (buffer-name)))
5360
5361returns "The buffer is foo".
5362
5363** Non-ASCII characters are now supported, if enable-multibyte-characters
5364is non-nil.
5365
5366These characters have character codes above 256. When inserted in the
5367buffer or stored in a string, they are represented as multibyte
5368characters that occupy several buffer positions each.
5369
5370*** When enable-multibyte-characters is non-nil, a single character in
5371a buffer or string can be two or more bytes (as many as four).
5372
5373Buffers and strings are still made up of unibyte elements;
5374character positions and string indices are always measured in bytes.
5375Therefore, moving forward one character can increase the buffer
5376position by 2, 3 or 4. The function forward-char moves by whole
5377characters, and therefore is no longer equivalent to
5378 (lambda (n) (goto-char (+ (point) n))).
5379
5380ASCII characters (codes 0 through 127) are still single bytes, always.
5381Sequences of byte values 128 through 255 are used to represent
5382non-ASCII characters. These sequences are called "multibyte
5383characters".
5384
5385The first byte of a multibyte character is always in the range 128
5386through 159 (octal 0200 through 0237). These values are called
5387"leading codes". The second and subsequent bytes are always in the
5388range 160 through 255 (octal 0240 through 0377). The first byte, the
5389leading code, determines how many bytes long the sequence is.
5390
5391*** The function forward-char moves over characters, and therefore
5392(forward-char 1) may increase point by more than 1 if it moves over a
5393multibyte character. Likewise, delete-char always deletes a
5394character, which may be more than one buffer position.
5395
5396This means that some Lisp programs, which assume that a character is
5397always one buffer position, need to be changed.
5398
5399However, all ASCII characters are always one buffer position.
5400
5401*** The regexp [\200-\377] no longer matches all non-ASCII characters,
5402because when enable-multibyte-characters is non-nil, these characters
5403have codes that are not in the range octal 200 to octal 377. However,
5404the regexp [^\000-\177] does match all non-ASCII characters,
5405guaranteed.
5406
5407*** The function char-boundary-p returns non-nil if position POS is
5408between two characters in the buffer (not in the middle of a
5409character).
5410
5411When the value is non-nil, it says what kind of character follows POS:
5412
5413 0 if POS is at an ASCII character or at the end of range,
5414 1 if POS is before a 2-byte length multi-byte form,
5415 2 if POS is at a head of 3-byte length multi-byte form,
5416 3 if POS is at a head of 4-byte length multi-byte form,
5417 4 if POS is at a head of multi-byte form of a composite character.
5418
5419*** The function char-bytes returns how many bytes the character CHAR uses.
5420
5421*** Strings can contain multibyte characters. The function
5422`length' returns the string length counting bytes, which may be
5423more than the number of characters.
5424
5425You can include a multibyte character in a string constant by writing
5426it literally. You can also represent it with a hex escape,
5427\xNNNNNNN..., using as many digits as necessary. Any character which
5428is not a valid hex digit terminates this construct. If you want to
5429follow it with a character that is a hex digit, write backslash and
5430newline in between; that will terminate the hex escape.
5431
5432*** The function concat-chars takes arguments which are characters
5433and returns a string containing those characters.
5434
5435*** The function sref access a multibyte character in a string.
5436(sref STRING INDX) returns the character in STRING at INDEX. INDEX
5437counts from zero. If INDEX is at a position in the middle of a
5438character, sref signals an error.
5439
5440*** The function chars-in-string returns the number of characters
5441in a string. This is less than the length of the string, if the
5442string contains multibyte characters (the length counts bytes).
5443
5444*** The function chars-in-region returns the number of characters
5445in a region from BEG to END. This is less than (- END BEG) if the
5446region contains multibyte characters (the length counts bytes).
5447
5448*** The function string-to-list converts a string to a list of
5449the characters in it. string-to-vector converts a string
5450to a vector of the characters in it.
5451
5452*** The function store-substring alters part of the contents
5453of a string. You call it as follows:
5454
5455 (store-substring STRING IDX OBJ)
5456
5457This says to alter STRING, by storing OBJ starting at index IDX in
5458STRING. OBJ may be either a character or a (smaller) string.
5459This function really does alter the contents of STRING.
5460Since it is impossible to change the length of an existing string,
5461it is an error if OBJ doesn't fit within STRING's actual length.
5462
5463*** char-width returns the width (in columns) of the character CHAR,
5464if it were displayed in the current buffer and the selected window.
5465
5466*** string-width returns the width (in columns) of the text in STRING,
5467if it were displayed in the current buffer and the selected window.
5468
5469*** truncate-string-to-width shortens a string, if necessary,
5470to fit within a certain number of columns. (Of course, it does
5471not alter the string that you give it; it returns a new string
5472which contains all or just part of the existing string.)
5473
5474(truncate-string-to-width STR END-COLUMN &optional START-COLUMN PADDING)
5475
5476This returns the part of STR up to column END-COLUMN.
5477
5478The optional argument START-COLUMN specifies the starting column.
5479If this is non-nil, then the first START-COLUMN columns of the string
5480are not included in the resulting value.
5481
5482The optional argument PADDING, if non-nil, is a padding character to be added
5483at the beginning and end the resulting string, to extend it to exactly
5484WIDTH columns. If PADDING is nil, that means do not pad; then, if STRING
5485is narrower than WIDTH, the value is equal to STRING.
5486
5487If PADDING and START-COLUMN are both non-nil, and if there is no clean
5488place in STRING that corresponds to START-COLUMN (because one
5489character extends across that column), then the padding character
5490PADDING is added one or more times at the beginning of the result
5491string, so that its columns line up as if it really did start at
5492column START-COLUMN.
5493
5494*** When the functions in the list after-change-functions are called,
5495the third argument is the number of bytes in the pre-change text, not
5496necessarily the number of characters. It is, in effect, the
5497difference in buffer position between the beginning and the end of the
5498changed text, before the change.
5499
5500*** The characters Emacs uses are classified in various character
5501sets, each of which has a name which is a symbol. In general there is
5502one character set for each script, not for each language.
5503
5504**** The function charsetp tests whether an object is a character set name.
5505
5506**** The variable charset-list holds a list of character set names.
5507
5508**** char-charset, given a character code, returns the name of the character
5509set that the character belongs to. (The value is a symbol.)
5510
5511**** split-char, given a character code, returns a list containing the
5512name of the character set, followed by one or two byte-values
5513which identify the character within that character set.
5514
5515**** make-char, given a character set name and one or two subsequent
5516byte-values, constructs a character code. This is roughly the
5517opposite of split-char.
5518
5519**** find-charset-region returns a list of the character sets
5520of all the characters between BEG and END.
5521
5522**** find-charset-string returns a list of the character sets
5523of all the characters in a string.
5524
5525*** Here are the Lisp facilities for working with coding systems
5526and specifying coding systems.
5527
5528**** The function coding-system-list returns a list of all coding
5529system names (symbols). With optional argument t, it returns a list
5530of all distinct base coding systems, not including variants.
5531(Variant coding systems are those like latin-1-dos, latin-1-unix
5532and latin-1-mac which specify the end-of-line conversion as well
5533as what to do about code conversion.)
5534
5535**** coding-system-p tests a symbol to see if it is a coding system
5536name. It returns t if so, nil if not.
5537
5538**** file-coding-system-alist specifies which coding systems to use
5539for certain file names. It works like network-coding-system-alist,
5540except that the PATTERN is matched against the file name.
5541
5542Each element has the format (PATTERN . VAL), where PATTERN determines
5543which file names the element applies to. PATTERN should be a regexp
5544to match against a file name.
5545
5546VAL is a coding system, a cons cell containing two coding systems, or
5547a function symbol. If VAL is a coding system, it is used for both
5548decoding what received from the network stream and encoding what sent
5549to the network stream. If VAL is a cons cell containing two coding
5550systems, the car specifies the coding system for decoding, and the cdr
5551specifies the coding system for encoding.
5552
5553If VAL is a function symbol, the function must return a coding system
5554or a cons cell containing two coding systems, which is used as above.
5555
5556**** The variable network-coding-system-alist specifies
5557the coding system to use for network sockets.
5558
5559Each element has the format (PATTERN . VAL), where PATTERN determines
5560which network sockets the element applies to. PATTERN should be
5561either a port number or a regular expression matching some network
5562service names.
5563
5564VAL is a coding system, a cons cell containing two coding systems, or
5565a function symbol. If VAL is a coding system, it is used for both
5566decoding what received from the network stream and encoding what sent
5567to the network stream. If VAL is a cons cell containing two coding
5568systems, the car specifies the coding system for decoding, and the cdr
5569specifies the coding system for encoding.
5570
5571If VAL is a function symbol, the function must return a coding system
5572or a cons cell containing two coding systems, which is used as above.
5573
5574**** process-coding-system-alist specifies which coding systems to use
5575for certain subprocess. It works like network-coding-system-alist,
5576except that the PATTERN is matched against the program name used to
5577start the subprocess.
5578
5579**** The variable default-process-coding-system specifies the coding
5580systems to use for subprocess (and net connection) input and output,
5581when nothing else specifies what to do. The value is a cons cell
5582(OUTPUT-CODING . INPUT-CODING). OUTPUT-CODING applies to output
5583to the subprocess, and INPUT-CODING applies to input from it.
5584
5585**** The variable coding-system-for-write, if non-nil, specifies the
5586coding system to use for writing a file, or for output to a synchronous
5587subprocess.
5588
5589It also applies to any asynchronous subprocess or network connection,
5590but in a different way: the value of coding-system-for-write when you
5591start the subprocess or connection affects that subprocess or
5592connection permanently or until overridden.
5593
5594The variable coding-system-for-write takes precedence over
5595file-coding-system-alist, process-coding-system-alist and
5596network-coding-system-alist, and all other methods of specifying a
5597coding system for output. But most of the time this variable is nil.
5598It exists so that Lisp programs can bind it to a specific coding
5599system for one operation at a time.
5600
5601**** coding-system-for-read applies similarly to input from
5602files, subprocesses or network connections.
5603
5604**** The function process-coding-system tells you what
5605coding systems(s) an existing subprocess is using.
5606The value is a cons cell,
5607 (DECODING-CODING-SYSTEM . ENCODING-CODING-SYSTEM)
5608where DECODING-CODING-SYSTEM is used for decoding output from
5609the subprocess, and ENCODING-CODING-SYSTEM is used for encoding
5610input to the subprocess.
5611
5612**** The function set-process-coding-system can be used to
5613change the coding systems in use for an existing subprocess.
5614
5615** Emacs has a new facility to help users manage the many
5616customization options. To make a Lisp program work with this facility,
5617you need to use the new macros defgroup and defcustom.
5618
5619You use defcustom instead of defvar, for defining a user option
5620variable. The difference is that you specify two additional pieces of
5621information (usually): the "type" which says what values are
5622legitimate, and the "group" which specifies the hierarchy for
5623customization.
5624
5625Thus, instead of writing
5626
5627 (defvar foo-blurgoze nil
5628 "*Non-nil means that foo will act very blurgozely.")
5629
5630you would now write this:
5631
5632 (defcustom foo-blurgoze nil
5633 "*Non-nil means that foo will act very blurgozely."
5634 :type 'boolean
5635 :group foo)
5636
5637The type `boolean' means that this variable has only
5638two meaningful states: nil and non-nil. Other type values
5639describe other possibilities; see the manual for Custom
5640for a description of them.
5641
5642The "group" argument is used to specify a group which the option
5643should belong to. You define a new group like this:
5644
5645 (defgroup ispell nil
5646 "Spell checking using Ispell."
5647 :group 'processes)
5648
5649The "group" argument in defgroup specifies the parent group. The root
5650group is called `emacs'; it should not contain any variables itself,
5651but only other groups. The immediate subgroups of `emacs' correspond
5652to the keywords used by C-h p. Under these subgroups come
5653second-level subgroups that belong to individual packages.
5654
5655Each Emacs package should have its own set of groups. A simple
5656package should have just one group; a more complex package should
5657have a hierarchy of its own groups. The sole or root group of a
5658package should be a subgroup of one or more of the "keyword"
5659first-level subgroups.
5660
5661** New `widget' library for inserting UI components in buffers.
5662
5663This library, used by the new custom library, is documented in a
5664separate manual that accompanies Emacs.
5665
5666** easy-mmode
5667
5668The easy-mmode package provides macros and functions that make
5669developing minor modes easier. Roughly, the programmer has to code
5670only the functionality of the minor mode. All the rest--toggles,
5671predicate, and documentation--can be done in one call to the macro
5672`easy-mmode-define-minor-mode' (see the documentation). See also
5673`easy-mmode-define-keymap'.
5674
5675** Text property changes
5676
5677*** The `intangible' property now works on overlays as well as on a
5678text property.
5679
5680*** The new functions next-char-property-change and
5681previous-char-property-change scan through the buffer looking for a
5682place where either a text property or an overlay might change. The
5683functions take two arguments, POSITION and LIMIT. POSITION is the
5684starting position for the scan. LIMIT says where to stop the scan.
5685
5686If no property change is found before LIMIT, the value is LIMIT. If
5687LIMIT is nil, scan goes to the beginning or end of the accessible part
5688of the buffer. If no property change is found, the value is the
5689position of the beginning or end of the buffer.
5690
5691*** In the `local-map' text property or overlay property, the property
5692value can now be a symbol whose function definition is a keymap. This
5693is an alternative to using the keymap itself.
5694
5695** Changes in invisibility features
5696
5697*** Isearch can now temporarily show parts of the buffer which are
5698hidden by an overlay with a invisible property, when the search match
5699is inside that portion of the buffer. To enable this the overlay
5700should have a isearch-open-invisible property which is a function that
5701would be called having the overlay as an argument, the function should
5702make the overlay visible.
5703
5704During incremental search the overlays are shown by modifying the
5705invisible and intangible properties, if beside this more actions are
5706needed the overlay should have a isearch-open-invisible-temporary
5707which is a function. The function is called with 2 arguments: one is
5708the overlay and the second is nil when it should show the overlay and
5709t when it should hide it.
5710
5711*** add-to-invisibility-spec, remove-from-invisibility-spec
5712
5713Modes that use overlays to hide portions of a buffer should set the
5714invisible property of the overlay to the mode's name (or another symbol)
5715and modify the `buffer-invisibility-spec' to include that symbol.
5716Use `add-to-invisibility-spec' and `remove-from-invisibility-spec' to
5717manipulate the `buffer-invisibility-spec'.
5718Here is an example of how to do this:
5719
5720 ;; If we want to display an ellipsis:
5721 (add-to-invisibility-spec '(my-symbol . t))
5722 ;; If you don't want ellipsis:
5723 (add-to-invisibility-spec 'my-symbol)
5724
5725 ...
5726 (overlay-put (make-overlay beginning end) 'invisible 'my-symbol)
5727
5728 ...
5729 ;; When done with the overlays:
5730 (remove-from-invisibility-spec '(my-symbol . t))
5731 ;; Or respectively:
5732 (remove-from-invisibility-spec 'my-symbol)
5733
5734** Changes in syntax parsing.
5735
5736*** The syntax-directed buffer-scan functions (such as
5737`parse-partial-sexp', `forward-word' and similar functions) can now
5738obey syntax information specified by text properties, if the variable
5739`parse-sexp-lookup-properties' is non-nil.
5740
5741If the value of `parse-sexp-lookup-properties' is nil, the behavior
5742is as before: the syntax-table of the current buffer is always
5743used to determine the syntax of the character at the position.
5744
5745When `parse-sexp-lookup-properties' is non-nil, the syntax of a
5746character in the buffer is calculated thus:
5747
5748 a) if the `syntax-table' text-property of that character
5749 is a cons, this cons becomes the syntax-type;
5750
5751 Valid values of `syntax-table' text-property are: nil, a valid
5752 syntax-table, and a valid syntax-table element, i.e.,
5753 a cons cell of the form (SYNTAX-CODE . MATCHING-CHAR).
5754
5755 b) if the character's `syntax-table' text-property
5756 is a syntax table, this syntax table is used
5757 (instead of the syntax-table of the current buffer) to
5758 determine the syntax type of the character.
5759
5760 c) otherwise the syntax-type is determined by the syntax-table
5761 of the current buffer.
5762
5763*** The meaning of \s in regular expressions is also affected by the
5764value of `parse-sexp-lookup-properties'. The details are the same as
5765for the syntax-directed buffer-scan functions.
5766
5767*** There are two new syntax-codes, `!' and `|' (numeric values 14
5768and 15). A character with a code `!' starts a comment which is ended
5769only by another character with the same code (unless quoted). A
5770character with a code `|' starts a string which is ended only by
5771another character with the same code (unless quoted).
5772
5773These codes are mainly meant for use as values of the `syntax-table'
5774text property.
5775
5776*** The function `parse-partial-sexp' has new semantics for the sixth
5777arg COMMENTSTOP. If it is `syntax-table', parse stops after the start
5778of a comment or a string, or after end of a comment or a string.
5779
5780*** The state-list which the return value from `parse-partial-sexp'
5781(and can also be used as an argument) now has an optional ninth
5782element: the character address of the start of last comment or string;
5783nil if none. The fourth and eighth elements have special values if the
5784string/comment is started by a "!" or "|" syntax-code.
5785
5786*** Since new features of `parse-partial-sexp' allow a complete
5787syntactic parsing, `font-lock' no longer supports
5788`font-lock-comment-start-regexp'.
5789
5790** Changes in face features
5791
5792*** The face functions are now unconditionally defined in Emacs, even
5793if it does not support displaying on a device that supports faces.
5794
5795*** The function face-documentation returns the documentation string
5796of a face (or nil if it doesn't have one).
5797
5798*** The function face-bold-p returns t if a face should be bold.
5799set-face-bold-p sets that flag.
5800
5801*** The function face-italic-p returns t if a face should be italic.
5802set-face-italic-p sets that flag.
5803
5804*** You can now specify foreground and background colors for text
5805by adding elements of the form (foreground-color . COLOR-NAME)
5806and (background-color . COLOR-NAME) to the list of faces in
5807the `face' property (either the character's text property or an
5808overlay property).
5809
5810This means that you no longer need to create named faces to use
5811arbitrary colors in a Lisp package.
5812
5813** Changes in file-handling functions
5814
5815*** File-access primitive functions no longer discard an extra redundant
5816directory name from the beginning of the file name. In other words,
5817they no longer do anything special with // or /~. That conversion
5818is now done only in substitute-in-file-name.
5819
5820This makes it possible for a Lisp program to open a file whose name
5821begins with ~.
5822
5823*** If copy-file is unable to set the date of the output file,
5824it now signals an error with the condition file-date-error.
5825
5826*** The inode number returned by file-attributes may be an integer (if
5827the number fits in a Lisp integer) or a list of integers.
5828
5829*** insert-file-contents can now read from a special file,
5830as long as the arguments VISIT and REPLACE are nil.
5831
5832*** The RAWFILE arg to find-file-noselect, if non-nil, now suppresses
5833character code conversion as well as other things.
5834
5835Meanwhile, this feature does work with remote file names
5836(formerly it did not).
5837
5838*** Lisp packages which create temporary files should use the TMPDIR
5839environment variable to decide which directory to put them in.
5840
5841*** interpreter-mode-alist elements now specify regexps
5842instead of constant strings.
5843
5844*** expand-file-name no longer treats `//' or `/~' specially. It used
5845to delete all the text of a file name up through the first slash of
5846any `//' or `/~' sequence. Now it passes them straight through.
5847
5848substitute-in-file-name continues to treat those sequences specially,
5849in the same way as before.
5850
5851*** The variable `format-alist' is more general now.
5852The FROM-FN and TO-FN in a format definition can now be strings
5853which specify shell commands to use as filters to perform conversion.
5854
5855*** The new function access-file tries to open a file, and signals an
5856error if that fails. If the open succeeds, access-file does nothing
5857else, and returns nil.
5858
5859*** The function insert-directory now signals an error if the specified
5860directory cannot be listed.
5861
5862** Changes in minibuffer input
5863
5864*** The functions read-buffer, read-variable, read-command, read-string
5865read-file-name, read-from-minibuffer and completing-read now take an
5866additional argument which specifies the default value. If this
5867argument is non-nil, it should be a string; that string is used in two
5868ways:
5869
5870 It is returned if the user enters empty input.
5871 It is available through the history command M-n.
5872
5873*** The functions read-string, read-from-minibuffer,
5874read-no-blanks-input and completing-read now take an additional
5875argument INHERIT-INPUT-METHOD. If this is non-nil, then the
5876minibuffer inherits the current input method and the setting of
5877enable-multibyte-characters from the previously current buffer.
5878
5879In an interactive spec, you can use M instead of s to read an
5880argument in this way.
5881
5882*** All minibuffer input functions discard text properties
5883from the text you enter in the minibuffer, unless the variable
5884minibuffer-allow-text-properties is non-nil.
5885
5886** Echo area features
5887
5888*** Clearing the echo area now runs the normal hook
5889echo-area-clear-hook. Note that the echo area can be used while the
5890minibuffer is active; in that case, the minibuffer is still active
5891after the echo area is cleared.
5892
5893*** The function current-message returns the message currently displayed
5894in the echo area, or nil if there is none.
5895
5896** Keyboard input features
5897
5898*** tty-erase-char is a new variable that reports which character was
5899set up as the terminal's erase character when time Emacs was started.
5900
5901*** num-nonmacro-input-events is the total number of input events
5902received so far from the terminal. It does not count those generated
5903by keyboard macros.
5904
5905** Frame-related changes
5906
5907*** make-frame runs the normal hook before-make-frame-hook just before
5908creating a frame, and just after creating a frame it runs the abnormal
5909hook after-make-frame-functions with the new frame as arg.
5910
5911*** The new hook window-configuration-change-hook is now run every time
5912the window configuration has changed. The frame whose configuration
5913has changed is the selected frame when the hook is run.
5914
5915*** Each frame now independently records the order for recently
5916selected buffers, in its buffer-list frame parameter, so that the
5917value of other-buffer is now based on the buffers recently displayed
5918in the selected frame.
5919
5920*** The value of the frame parameter vertical-scroll-bars
5921is now `left', `right' or nil. A non-nil value specifies
5922which side of the window to put the scroll bars on.
5923
5924** X Windows features
5925
5926*** You can examine X resources for other applications by binding
5927x-resource-class around a call to x-get-resource. The usual value of
5928x-resource-class is "Emacs", which is the correct value for Emacs.
5929
5930*** In menus, checkboxes and radio buttons now actually work.
5931The menu displays the current status of the box or button.
5932
5933*** The function x-list-fonts now takes an optional fourth argument
5934MAXIMUM which sets a limit on how many matching fonts to return.
5935A smaller value of MAXIMUM makes the function faster.
5936
5937If the only question is whether *any* font matches the pattern,
5938it is good to supply 1 for this argument.
5939
5940** Subprocess features
5941
5942*** A reminder: it is no longer necessary for subprocess filter
5943functions and sentinels to do save-match-data, because Emacs does this
5944automatically.
5945
5946*** The new function shell-command-to-string executes a shell command
5947and returns the output from the command as a string.
5948
5949*** The new function process-contact returns t for a child process,
5950and (HOSTNAME SERVICE) for a net connection.
5951
5952** An error in running pre-command-hook or post-command-hook
5953does clear the variable to nil. The documentation was wrong before.
5954
5955** In define-key-after, if AFTER is t, the new binding now always goes
5956at the end of the keymap. If the keymap is a menu, this means it
5957goes after the other menu items.
5958
5959** If you have a program that makes several changes in the same area
5960of the buffer, you can use the macro combine-after-change-calls
5961around that Lisp code to make it faster when after-change hooks
5962are in use.
5963
5964The macro arranges to call the after-change functions just once for a
5965series of several changes--if that seems safe.
5966
5967Don't alter the variables after-change-functions and
5968after-change-function within the body of a combine-after-change-calls
5969form.
5970
5971** If you define an abbrev (with define-abbrev) whose EXPANSION
5972is not a string, then the abbrev does not expand in the usual sense,
5973but its hook is still run.
5974
5975** Normally, the Lisp debugger is not used (even if you have enabled it)
5976for errors that are handled by condition-case.
5977
5978If you set debug-on-signal to a non-nil value, then the debugger is called
5979regardless of whether there is a handler for the condition. This is
5980useful for debugging problems that happen inside of a condition-case.
5981
5982This mode of operation seems to be unreliable in other ways. Errors that
5983are normal and ought to be handled, perhaps in timers or process
5984filters, will instead invoke the debugger. So don't say you weren't
5985warned.
5986
5987** The new variable ring-bell-function lets you specify your own
5988way for Emacs to "ring the bell".
5989
5990** If run-at-time's TIME argument is t, the action is repeated at
5991integral multiples of REPEAT from the epoch; this is useful for
5992functions like display-time.
5993
5994** You can use the function locate-library to find the precise file
5995name of a Lisp library. This isn't new, but wasn't documented before.
5996
5997** Commands for entering view mode have new optional arguments that
5998can be used from Lisp. Low-level entrance to and exit from view mode
5999is done by functions view-mode-enter and view-mode-exit.
6000
6001** batch-byte-compile-file now makes Emacs return a nonzero status code
6002if there is an error in compilation.
6003
6004** pop-to-buffer, switch-to-buffer-other-window and
6005switch-to-buffer-other-frame now accept an additional optional
6006argument NORECORD, much like switch-to-buffer. If it is non-nil,
6007they don't put the buffer at the front of the buffer list.
6008
6009** If your .emacs file leaves the *scratch* buffer non-empty,
6010Emacs does not display the startup message, so as to avoid changing
6011the *scratch* buffer.
6012
6013** The new function regexp-opt returns an efficient regexp to match a string.
6014The arguments are STRINGS and (optionally) PAREN. This function can be used
6015where regexp matching or searching is intensively used and speed is important,
6016e.g., in Font Lock mode.
6017
6018** The variable buffer-display-count is local to each buffer,
6019and is incremented each time the buffer is displayed in a window.
6020It starts at 0 when the buffer is created.
6021
6022** The new function compose-mail starts composing a mail message
6023using the user's chosen mail composition agent (specified with the
6024variable mail-user-agent). It has variants compose-mail-other-window
6025and compose-mail-other-frame.
6026
6027** The `user-full-name' function now takes an optional parameter which
6028can either be a number (the UID) or a string (the login name). The
6029full name of the specified user will be returned.
6030
6031** Lisp packages that load files of customizations, or any other sort
6032of user profile, should obey the variable init-file-user in deciding
6033where to find it. They should load the profile of the user name found
6034in that variable. If init-file-user is nil, meaning that the -q
6035option was used, then Lisp packages should not load the customization
6036files at all.
6037
6038** format-time-string now allows you to specify the field width
6039and type of padding. This works as in printf: you write the field
6040width as digits in the middle of a %-construct. If you start
6041the field width with 0, it means to pad with zeros.
6042
6043For example, %S normally specifies the number of seconds since the
6044minute; %03S means to pad this with zeros to 3 positions, %_3S to pad
6045with spaces to 3 positions. Plain %3S pads with zeros, because that
6046is how %S normally pads to two positions.
6047
6048** thing-at-point now supports a new kind of "thing": url.
6049
6050** imenu.el changes.
6051
6052You can now specify a function to be run when selecting an
6053item from menu created by imenu.
6054
6055An example of using this feature: if we define imenu items for the
6056#include directives in a C file, we can open the included file when we
6057select one of those items.
6058\f
6059* Emacs 19.34 is a bug-fix release with no user-visible changes.
6060\f
6061* Changes in Emacs 19.33.
6062
6063** Bibtex mode no longer turns on Auto Fill automatically. (No major
6064mode should do that--it is the user's choice.)
6065
6066** The variable normal-auto-fill-function specifies the function to
6067use for auto-fill-function, if and when Auto Fill is turned on.
6068Major modes can set this locally to alter how Auto Fill works.
6069\f
6070* Editing Changes in Emacs 19.32
6071
6072** C-x f with no argument now signals an error.
6073To set the fill column at the current column, use C-u C-x f.
6074
6075** Expanding dynamic abbrevs with M-/ is now smarter about case
6076conversion. If you type the abbreviation with mixed case, and it
6077matches the beginning of the expansion including case, then the
6078expansion is copied verbatim. Using SPC M-/ to copy an additional
6079word always copies it verbatim except when the previous copied word is
6080all caps.
6081
6082** On a non-windowing terminal, which can display only one Emacs frame
6083at a time, creating a new frame with C-x 5 2 also selects that frame.
6084
6085When using a display that can show multiple frames at once, C-x 5 2
6086does make the frame visible, but does not select it. This is the same
6087as in previous Emacs versions.
6088
6089** You can use C-x 5 2 to create multiple frames on MSDOS, just as on a
6090non-X terminal on Unix. Of course, only one frame is visible at any
6091time, since your terminal doesn't have the ability to display multiple
6092frames.
6093
6094** On Windows, set win32-pass-alt-to-system to a non-nil value
6095if you would like tapping the Alt key to invoke the Windows menu.
6096This feature is not enabled by default; since the Alt key is also the
6097Meta key, it is too easy and painful to activate this feature by
6098accident.
6099
6100** The command apply-macro-to-region-lines repeats the last defined
6101keyboard macro once for each complete line within the current region.
6102It does this line by line, by moving point to the beginning of that
6103line and then executing the macro.
6104
6105This command is not new, but was never documented before.
6106
6107** You can now use Mouse-1 to place the region around a string constant
6108(something surrounded by doublequote characters or other delimiter
6109characters of like syntax) by double-clicking on one of the delimiting
6110characters.
6111
6112** Font Lock mode
6113
6114*** Font Lock support modes
6115
6116Font Lock can be configured to use Fast Lock mode and Lazy Lock mode (see
6117below) in a flexible way. Rather than adding the appropriate function to the
6118hook font-lock-mode-hook, you can use the new variable font-lock-support-mode
6119to control which modes have Fast Lock mode or Lazy Lock mode turned on when
6120Font Lock mode is enabled.
6121
6122For example, to use Fast Lock mode when Font Lock mode is turned on, put:
6123
6124 (setq font-lock-support-mode 'fast-lock-mode)
6125
6126in your ~/.emacs.
6127
6128*** lazy-lock
6129
6130The lazy-lock package speeds up Font Lock mode by making fontification occur
6131only when necessary, such as when a previously unfontified part of the buffer
6132becomes visible in a window. When you create a buffer with Font Lock mode and
6133Lazy Lock mode turned on, the buffer is not fontified. When certain events
6134occur (such as scrolling), Lazy Lock makes sure that the visible parts of the
6135buffer are fontified. Lazy Lock also defers on-the-fly fontification until
6136Emacs has been idle for a given amount of time.
6137
6138To use this package, put in your ~/.emacs:
6139
6140 (setq font-lock-support-mode 'lazy-lock-mode)
6141
6142To control the package behaviour, see the documentation for `lazy-lock-mode'.
6143
6144** Changes in BibTeX mode.
6145
6146*** For all entries allow spaces and tabs between opening brace or
6147paren and key.
6148
6149*** Non-escaped double-quoted characters (as in `Sch"of') are now
6150supported.
6151
6152** Gnus changes.
6153
6154Gnus, the Emacs news reader, has undergone further rewriting. Many new
6155commands and variables have been added. There should be no
6156significant incompatibilities between this Gnus version and the
6157previously released version, except in the message composition area.
6158
6159Below is a list of the more user-visible changes. Coding changes
6160between Gnus 5.1 and 5.2 are more extensive.
6161
6162*** A new message composition mode is used. All old customization
6163variables for mail-mode, rnews-reply-mode and gnus-msg are now
6164obsolete.
6165
6166*** Gnus is now able to generate "sparse" threads -- threads where
6167missing articles are represented by empty nodes.
6168
6169 (setq gnus-build-sparse-threads 'some)
6170
6171*** Outgoing articles are stored on a special archive server.
6172
6173 To disable this: (setq gnus-message-archive-group nil)
6174
6175*** Partial thread regeneration now happens when articles are
6176referred.
6177
6178*** Gnus can make use of GroupLens predictions:
6179
6180 (setq gnus-use-grouplens t)
6181
6182*** A trn-line tree buffer can be displayed.
6183
6184 (setq gnus-use-trees t)
6185
6186*** An nn-like pick-and-read minor mode is available for the summary
6187buffers.
6188
6189 (add-hook 'gnus-summary-mode-hook 'gnus-pick-mode)
6190
6191*** In binary groups you can use a special binary minor mode:
6192
6193 `M-x gnus-binary-mode'
6194
6195*** Groups can be grouped in a folding topic hierarchy.
6196
6197 (add-hook 'gnus-group-mode-hook 'gnus-topic-mode)
6198
6199*** Gnus can re-send and bounce mail.
6200
6201 Use the `S D r' and `S D b'.
6202
6203*** Groups can now have a score, and bubbling based on entry frequency
6204is possible.
6205
6206 (add-hook 'gnus-summary-exit-hook 'gnus-summary-bubble-group)
6207
6208*** Groups can be process-marked, and commands can be performed on
6209groups of groups.
6210
6211*** Caching is possible in virtual groups.
6212
6213*** nndoc now understands all kinds of digests, mail boxes, rnews news
6214batches, ClariNet briefs collections, and just about everything else.
6215
6216*** Gnus has a new backend (nnsoup) to create/read SOUP packets.
6217
6218*** The Gnus cache is much faster.
6219
6220*** Groups can be sorted according to many criteria.
6221
6222 For instance: (setq gnus-group-sort-function 'gnus-group-sort-by-rank)
6223
6224*** New group parameters have been introduced to set list-address and
6225expiration times.
6226
6227*** All formatting specs allow specifying faces to be used.
6228
6229*** There are several more commands for setting/removing/acting on
6230process marked articles on the `M P' submap.
6231
6232*** The summary buffer can be limited to show parts of the available
6233articles based on a wide range of criteria. These commands have been
6234bound to keys on the `/' submap.
6235
6236*** Articles can be made persistent -- as an alternative to saving
6237articles with the `*' command.
6238
6239*** All functions for hiding article elements are now toggles.
6240
6241*** Article headers can be buttonized.
6242
6243 (add-hook 'gnus-article-display-hook 'gnus-article-add-buttons-to-head)
6244
6245*** All mail backends support fetching articles by Message-ID.
6246
6247*** Duplicate mail can now be treated properly. See the
6248`nnmail-treat-duplicates' variable.
6249
6250*** All summary mode commands are available directly from the article
6251buffer.
6252
6253*** Frames can be part of `gnus-buffer-configuration'.
6254
6255*** Mail can be re-scanned by a daemonic process.
6256
6257*** Gnus can make use of NoCeM files to filter spam.
6258
6259 (setq gnus-use-nocem t)
6260
6261*** Groups can be made permanently visible.
6262
6263 (setq gnus-permanently-visible-groups "^nnml:")
6264
6265*** Many new hooks have been introduced to make customizing easier.
6266
6267*** Gnus respects the Mail-Copies-To header.
6268
6269*** Threads can be gathered by looking at the References header.
6270
6271 (setq gnus-summary-thread-gathering-function
6272 'gnus-gather-threads-by-references)
6273
6274*** Read articles can be stored in a special backlog buffer to avoid
6275refetching.
6276
6277 (setq gnus-keep-backlog 50)
6278
6279*** A clean copy of the current article is always stored in a separate
6280buffer to allow easier treatment.
6281
6282*** Gnus can suggest where to save articles. See `gnus-split-methods'.
6283
6284*** Gnus doesn't have to do as much prompting when saving.
6285
6286 (setq gnus-prompt-before-saving t)
6287
6288*** gnus-uu can view decoded files asynchronously while fetching
6289articles.
6290
6291 (setq gnus-uu-grabbed-file-functions 'gnus-uu-grab-view)
6292
6293*** Filling in the article buffer now works properly on cited text.
6294
6295*** Hiding cited text adds buttons to toggle hiding, and how much
6296cited text to hide is now customizable.
6297
6298 (setq gnus-cited-lines-visible 2)
6299
6300*** Boring headers can be hidden.
6301
6302 (add-hook 'gnus-article-display-hook 'gnus-article-hide-boring-headers)
6303
6304*** Default scoring values can now be set from the menu bar.
6305
6306*** Further syntax checking of outgoing articles have been added.
6307
6308The Gnus manual has been expanded. It explains all these new features
6309in greater detail.
6310\f
6311* Lisp Changes in Emacs 19.32
6312
6313** The function set-visited-file-name now accepts an optional
6314second argument NO-QUERY. If it is non-nil, then the user is not
6315asked for confirmation in the case where the specified file already
6316exists.
6317
6318** The variable print-length applies to printing vectors and bitvectors,
6319as well as lists.
6320
6321** The new function keymap-parent returns the parent keymap
6322of a given keymap.
6323
6324** The new function set-keymap-parent specifies a new parent for a
6325given keymap. The arguments are KEYMAP and PARENT. PARENT must be a
6326keymap or nil.
6327
6328** Sometimes menu keymaps use a command name, a symbol, which is really
6329an automatically generated alias for some other command, the "real"
6330name. In such a case, you should give that alias symbol a non-nil
6331menu-alias property. That property tells the menu system to look for
6332equivalent keys for the real name instead of equivalent keys for the
6333alias.
6334\f
6335* Editing Changes in Emacs 19.31
6336
6337** Freedom of the press restricted in the United States.
6338
6339Emacs has been censored in accord with the Communications Decency Act.
6340This includes removing some features of the doctor program. That law
6341was described by its supporters as a ban on pornography, but it bans
6342far more than that. The Emacs distribution has never contained any
6343pornography, but parts of it were nonetheless prohibited.
6344
6345For information on US government censorship of the Internet, and what
6346you can do to bring back freedom of the press, see the web site
6347`http://www.vtw.org/'.
6348
6349** A note about C mode indentation customization.
6350
6351The old (Emacs 19.29) ways of specifying a C indentation style
6352do not normally work in the new implementation of C mode.
6353It has its own methods of customizing indentation, which are
6354much more powerful than the old C mode. See the Editing Programs
6355chapter of the manual for details.
6356
6357However, you can load the library cc-compat to make the old
6358customization variables take effect.
6359
6360** Marking with the mouse.
6361
6362When you mark a region with the mouse, the region now remains
6363highlighted until the next input event, regardless of whether you are
6364using M-x transient-mark-mode.
6365
6366** Improved Windows NT/95 support.
6367
6368*** Emacs now supports scroll bars on Windows NT and Windows 95.
6369
6370*** Emacs now supports subprocesses on Windows 95. (Subprocesses used
6371to work on NT only and not on 95.)
6372
6373*** There are difficulties with subprocesses, though, due to problems
6374in Windows, beyond the control of Emacs. They work fine as long as
6375you run Windows applications. The problems arise when you run a DOS
6376application in a subprocesses. Since current shells run as DOS
6377applications, these problems are significant.
6378
6379If you run a DOS application in a subprocess, then the application is
6380likely to busy-wait, which means that your machine will be 100% busy.
6381However, if you don't mind the temporary heavy load, the subprocess
6382will work OK as long as you tell it to terminate before you start any
6383other DOS application as a subprocess.
6384
6385Emacs is unable to terminate or interrupt a DOS subprocess.
6386You have to do this by providing input directly to the subprocess.
6387
6388If you run two DOS applications at the same time in two separate
6389subprocesses, even if one of them is asynchronous, you will probably
6390have to reboot your machine--until then, it will remain 100% busy.
6391Windows simply does not cope when one Windows process tries to run two
6392separate DOS subprocesses. Typing CTL-ALT-DEL and then choosing
6393Shutdown seems to work although it may take a few minutes.
6394
6395** M-x resize-minibuffer-mode.
6396
6397This command, not previously mentioned in NEWS, toggles a mode in
6398which the minibuffer window expands to show as many lines as the
6399minibuffer contains.
6400
6401** `title' frame parameter and resource.
6402
6403The `title' X resource now specifies just the frame title, nothing else.
6404It does not affect the name used for looking up other X resources.
6405It works by setting the new `title' frame parameter, which likewise
6406affects just the displayed title of the frame.
6407
6408The `name' parameter continues to do what it used to do:
6409it specifies the frame name for looking up X resources,
6410and also serves as the default for the displayed title
6411when the `title' parameter is unspecified or nil.
6412
6413** Emacs now uses the X toolkit by default, if you have a new
6414enough version of X installed (X11R5 or newer).
6415
6416** When you compile Emacs with the Motif widget set, Motif handles the
6417F10 key by activating the menu bar. To avoid confusion, the usual
6418Emacs binding of F10 is replaced with a no-op when using Motif.
6419
6420If you want to be able to use F10 in Emacs, you can rebind the Motif
6421menubar to some other key which you don't use. To do so, add
6422something like this to your X resources file. This example rebinds
6423the Motif menu bar activation key to S-F12:
6424
6425 Emacs*defaultVirtualBindings: osfMenuBar : Shift<Key>F12
6426
6427** In overwrite mode, DEL now inserts spaces in most cases
6428to replace the characters it "deletes".
6429
6430** The Rmail summary now shows the number of lines in each message.
6431
6432** Rmail has a new command M-x unforward-rmail-message, which extracts
6433a forwarded message from the message that forwarded it. To use it,
6434select a message which contains a forwarded message and then type the command.
6435It inserts the forwarded message as a separate Rmail message
6436immediately after the selected one.
6437
6438This command also undoes the textual modifications that are standardly
6439made, as part of forwarding, by Rmail and other mail reader programs.
6440
6441** Turning off saving of .saves-... files in your home directory.
6442
6443Each Emacs session writes a file named .saves-... in your home
6444directory to record which files M-x recover-session should recover.
6445If you exit Emacs normally with C-x C-c, it deletes that file. If
6446Emacs or the operating system crashes, the file remains for M-x
6447recover-session.
6448
6449You can turn off the writing of these files by setting
6450auto-save-list-file-name to nil. If you do this, M-x recover-session
6451will not work.
6452
6453Some previous Emacs versions failed to delete these files even on
6454normal exit. This is fixed now. If you are thinking of turning off
6455this feature because of past experiences with versions that had this
6456bug, it would make sense to check whether you still want to do so
6457now that the bug is fixed.
6458
6459** Changes to Version Control (VC)
6460
6461There is a new variable, vc-follow-symlinks. It indicates what to do
6462when you visit a link to a file that is under version control.
6463Editing the file through the link bypasses the version control system,
6464which is dangerous and probably not what you want.
6465
6466If this variable is t, VC follows the link and visits the real file,
6467telling you about it in the echo area. If it is `ask' (the default),
6468VC asks for confirmation whether it should follow the link. If nil,
6469the link is visited and a warning displayed.
6470
6471** iso-acc.el now lets you specify a choice of language.
6472Languages include "latin-1" (the default) and "latin-2" (which
6473is designed for entering ISO Latin-2 characters).
6474
6475There are also choices for specific human languages such as French and
6476Portuguese. These are subsets of Latin-1, which differ in that they
6477enable only the accent characters needed for particular language.
6478The other accent characters, not needed for the chosen language,
6479remain normal.
6480
6481** Posting articles and sending mail now has M-TAB completion on various
6482header fields (Newsgroups, To, CC, ...).
6483
6484Completion in the Newsgroups header depends on the list of groups
6485known to your news reader. Completion in the Followup-To header
6486offers those groups which are in the Newsgroups header, since
6487Followup-To usually just holds one of those.
6488
6489Completion in fields that hold mail addresses works based on the list
6490of local users plus your aliases. Additionally, if your site provides
6491a mail directory or a specific host to use for any unrecognized user
6492name, you can arrange to query that host for completion also. (See the
6493documentation of variables `mail-directory-process' and
6494`mail-directory-stream'.)
6495
6496** A greatly extended sgml-mode offers new features such as (to be configured)
6497skeletons with completing read for tags and attributes, typing named
6498characters including optionally all 8bit characters, making tags invisible
6499with optional alternate display text, skipping and deleting tag(pair)s.
6500
6501Note: since Emacs' syntax feature cannot limit the special meaning of ', " and
6502- to inside <>, for some texts the result, especially of font locking, may be
6503wrong (see `sgml-specials' if you get wrong results).
6504
6505The derived html-mode configures this with tags and attributes more or
6506less HTML3ish. It also offers optional quick keys like C-c 1 for
6507headline or C-c u for unordered list (see `html-quick-keys'). Edit /
6508Text Properties / Face or M-g combinations create tags as applicable.
6509Outline minor mode is supported and level 1 font-locking tries to
6510fontify tag contents (which only works when they fit on one line, due
6511to a limitation in font-lock).
6512
6513External viewing via browse-url can occur automatically upon saving.
6514
6515** M-x imenu-add-to-menubar now adds to the menu bar for the current
6516buffer only. If you want to put an Imenu item in the menu bar for all
6517buffers that use a particular major mode, use the mode hook, as in
6518this example:
6519
6520 (add-hook 'emacs-lisp-mode-hook
6521 '(lambda () (imenu-add-to-menubar "Index")))
6522
6523** Changes in BibTeX mode.
6524
6525*** Field names may now contain digits, hyphens, and underscores.
6526
6527*** Font Lock mode is now supported.
6528
6529*** bibtex-make-optional-field is no longer interactive.
6530
6531*** If bibtex-maintain-sorted-entries is non-nil, inserting new
6532entries is now done with a faster algorithm. However, inserting
6533will fail in this case if the buffer contains invalid entries or
6534isn't in sorted order, so you should finish each entry with C-c C-c
6535(bibtex-close-entry) after you have inserted or modified it.
6536The default value of bibtex-maintain-sorted-entries is nil.
6537
6538*** Function `show-all' is no longer bound to a key, since C-u C-c C-q
6539does the same job.
6540
6541*** Entries with quotes inside quote-delimited fields (as `author =
6542"Stefan Sch{\"o}f"') are now supported.
6543
6544*** Case in field names doesn't matter anymore when searching for help
6545text.
6546
6547** Font Lock mode
6548
6549*** Global Font Lock mode
6550
6551Font Lock mode can be turned on globally, in buffers that support it, by the
6552new command global-font-lock-mode. You can use the new variable
6553font-lock-global-modes to control which modes have Font Lock mode automagically
6554turned on. By default, this variable is set so that Font Lock mode is turned
6555on globally where the buffer mode supports it.
6556
6557For example, to automagically turn on Font Lock mode where supported, put:
6558
6559 (global-font-lock-mode t)
6560
6561in your ~/.emacs.
6562
6563*** Local Refontification
6564
6565In Font Lock mode, editing a line automatically refontifies that line only.
6566However, if your change alters the syntactic context for following lines,
6567those lines remain incorrectly fontified. To refontify them, use the new
6568command M-g M-g (font-lock-fontify-block).
6569
6570In certain major modes, M-g M-g refontifies the entire current function.
6571(The variable font-lock-mark-block-function controls how to find the
6572current function.) In other major modes, M-g M-g refontifies 16 lines
6573above and below point.
6574
6575With a prefix argument N, M-g M-g refontifies N lines above and below point.
6576
6577** Follow mode
6578
6579Follow mode is a new minor mode combining windows showing the same
6580buffer into one tall "virtual window". The windows are typically two
6581side-by-side windows. Follow mode makes them scroll together as if
6582they were a unit. To use it, go to a frame with just one window,
6583split it into two side-by-side windows using C-x 3, and then type M-x
6584follow-mode.
6585
6586M-x follow-mode turns off Follow mode if it is already enabled.
6587
6588To display two side-by-side windows and activate Follow mode, use the
6589command M-x follow-delete-other-windows-and-split.
6590
6591** hide-show changes.
6592
6593The hooks hs-hide-hooks and hs-show-hooks have been renamed
6594to hs-hide-hook and hs-show-hook, to follow the convention for
6595normal hooks.
6596
6597** Simula mode now has a menu containing the most important commands.
6598The new command simula-indent-exp is bound to C-M-q.
6599
6600** etags can now handle programs written in Erlang. Files are
6601recognised by the extensions .erl and .hrl. The tagged lines are
6602those that begin a function, record, or macro.
6603
6604** MSDOS Changes
6605
6606*** It is now possible to compile Emacs with the version 2 of DJGPP.
6607Compilation with DJGPP version 1 also still works.
6608
6609*** The documentation of DOS-specific aspects of Emacs was rewritten
6610and expanded; see the ``MS-DOS'' node in the on-line docs.
6611
6612*** Emacs now uses ~ for backup file names, not .bak.
6613
6614*** You can simulate mouse-3 on two-button mice by simultaneously
6615pressing both mouse buttons.
6616
6617*** A number of packages and commands which previously failed or had
6618restricted functionality on MS-DOS, now work. The most important ones
6619are:
6620
6621**** Printing (both with `M-x lpr-buffer' and with `ps-print' package)
6622now works.
6623
6624**** `Ediff' works (in a single-frame mode).
6625
6626**** `M-x display-time' can be used on MS-DOS (due to the new
6627implementation of Emacs timers, see below).
6628
6629**** `Dired' supports Unix-style shell wildcards.
6630
6631**** The `c-macro-expand' command now works as on other platforms.
6632
6633**** `M-x recover-session' works.
6634
6635**** `M-x list-colors-display' displays all the available colors.
6636
6637**** The `TPU-EDT' package works.
6638\f
6639* Lisp changes in Emacs 19.31.
6640
6641** The function using-unix-filesystems on Windows NT and Windows 95
6642tells Emacs to read and write files assuming that they reside on a
6643remote Unix filesystem. No CR/LF translation is done on any files in
6644this case. Invoking using-unix-filesystems with t activates this
6645behavior, and invoking it with any other value deactivates it.
6646
6647** Change in system-type and system-configuration values.
6648
6649The value of system-type on a Linux-based GNU system is now `lignux',
6650not `linux'. This means that some programs which use `system-type'
6651need to be changed. The value of `system-configuration' will also
6652be different.
6653
6654It is generally recommended to use `system-configuration' rather
6655than `system-type'.
6656
6657See the file LINUX-GNU in this directory for more about this.
6658
6659** The functions shell-command and dired-call-process
6660now run file name handlers for default-directory, if it has them.
6661
6662** Undoing the deletion of text now restores the positions of markers
6663that pointed into or next to the deleted text.
6664
6665** Timers created with run-at-time now work internally to Emacs, and
6666no longer use a separate process. Therefore, they now work more
6667reliably and can be used for shorter time delays.
6668
6669The new function run-with-timer is a convenient way to set up a timer
6670to run a specified amount of time after the present. A call looks
6671like this:
6672
6673 (run-with-timer SECS REPEAT FUNCTION ARGS...)
6674
6675SECS says how many seconds should elapse before the timer happens.
6676It may be an integer or a floating point number. When the timer
6677becomes ripe, the action is to call FUNCTION with arguments ARGS.
6678
6679REPEAT gives the interval for repeating the timer (measured in
6680seconds). It may be an integer or a floating point number. nil or 0
6681means don't repeat at all--call FUNCTION just once.
6682
6683*** with-timeout provides an easy way to do something but give
6684up if too much time passes.
6685
6686 (with-timeout (SECONDS TIMEOUT-FORMS...) BODY...)
6687
6688This executes BODY, but gives up after SECONDS seconds.
6689If it gives up, it runs the TIMEOUT-FORMS and returns the value
6690of the last one of them. Normally it returns the value of the last
6691form in BODY.
6692
6693*** You can now arrange to call a function whenever Emacs is idle for
6694a certain length of time. To do this, call run-with-idle-timer. A
6695call looks like this:
6696
6697 (run-with-idle-timer SECS REPEAT FUNCTION ARGS...)
6698
6699SECS says how many seconds of idleness should elapse before the timer
6700runs. It may be an integer or a floating point number. When the
6701timer becomes ripe, the action is to call FUNCTION with arguments
6702ARGS.
6703
6704Emacs becomes idle whenever it finishes executing a keyboard or mouse
6705command. It remains idle until it receives another keyboard or mouse
6706command.
6707
6708REPEAT, if non-nil, means this timer should be activated again each
6709time Emacs becomes idle and remains idle for SECS seconds The timer
6710does not repeat if Emacs *remains* idle; it runs at most once after
6711each time Emacs becomes idle.
6712
6713If REPEAT is nil, the timer runs just once, the first time Emacs is
6714idle for SECS seconds.
6715
6716*** post-command-idle-hook is now obsolete; you shouldn't use it at
6717all, because it interferes with the idle timer mechanism. If your
6718programs use post-command-idle-hook, convert them to use idle timers
6719instead.
6720
6721*** y-or-n-p-with-timeout lets you ask a question but give up if
6722there is no answer within a certain time.
6723
6724 (y-or-n-p-with-timeout PROMPT SECONDS DEFAULT-VALUE)
6725
6726asks the question PROMPT (just like y-or-n-p). If the user answers
6727within SECONDS seconds, it returns the answer that the user gave.
6728Otherwise it gives up after SECONDS seconds, and returns DEFAULT-VALUE.
6729
6730** Minor change to `encode-time': you can now pass more than seven
6731arguments. If you do that, the first six arguments have the usual
6732meaning, the last argument is interpreted as the time zone, and the
6733arguments in between are ignored.
6734
6735This means that it works to use the list returned by `decode-time' as
6736the list of arguments for `encode-time'.
6737
6738** The default value of load-path now includes the directory
6739/usr/local/share/emacs/VERSION/site-lisp In addition to
6740/usr/local/share/emacs/site-lisp. You can use this new directory for
6741site-specific Lisp packages that belong with a particular Emacs
6742version.
6743
6744It is not unusual for a Lisp package that works well in one Emacs
6745version to cause trouble in another. Sometimes packages need updating
6746for incompatible changes; sometimes they look at internal data that
6747has changed; sometimes the package has been installed in Emacs itself
6748and the installed version should be used. Whatever the reason for the
6749problem, this new feature makes it easier to solve.
6750
6751** When your program contains a fixed file name (like .completions or
6752.abbrev.defs), the file name usually needs to be different on operating
6753systems with limited file name syntax.
6754
6755Now you can avoid ad-hoc conditionals by using the function
6756convert-standard-filename to convert the file name to a proper form
6757for each operating system. Here is an example of use, from the file
6758completions.el:
6759
6760(defvar save-completions-file-name
6761 (convert-standard-filename "~/.completions")
6762 "*The filename to save completions to.")
6763
6764This sets the variable save-completions-file-name to a value that
6765depends on the operating system, because the definition of
6766convert-standard-filename depends on the operating system. On
6767Unix-like systems, it returns the specified file name unchanged. On
6768MS-DOS, it adapts the name to fit the limitations of that system.
6769
6770** The interactive spec N now returns the numeric prefix argument
6771rather than the raw prefix argument. (It still reads a number using the
6772minibuffer if there is no prefix argument at all.)
6773
6774** When a process is deleted, this no longer disconnects the process
6775marker from its buffer position.
6776
6777** The variable garbage-collection-messages now controls whether
6778Emacs displays a message at the beginning and end of garbage collection.
6779The default is nil, meaning there are no messages.
6780
6781** The variable debug-ignored-errors specifies certain kinds of errors
6782that should not enter the debugger. Its value is a list of error
6783condition symbols and/or regular expressions. If the error has any
6784of the condition symbols listed, or if any of the regular expressions
6785matches the error message, then that error does not enter the debugger,
6786regardless of the value of debug-on-error.
6787
6788This variable is initialized to match certain common but uninteresting
6789errors that happen often during editing.
6790
6791** The new function error-message-string converts an error datum
6792into its error message. The error datum is what condition-case
6793puts into the variable, to describe the error that happened.
6794
6795** Anything that changes which buffer appears in a given window
6796now runs the window-scroll-functions for that window.
6797
6798** The new function get-buffer-window-list returns a list of windows displaying
6799a buffer. The function is called with the buffer (a buffer object or a buffer
6800name) and two optional arguments specifying the minibuffer windows and frames
6801to search. Therefore this function takes optional args like next-window etc.,
6802and not get-buffer-window.
6803
6804** buffer-substring now runs the hook buffer-access-fontify-functions,
6805calling each function with two arguments--the range of the buffer
6806being accessed. buffer-substring-no-properties does not call them.
6807
6808If you use this feature, you should set the variable
6809buffer-access-fontified-property to a non-nil symbol, which is a
6810property name. Then, if all the characters in the buffer range have a
6811non-nil value for that property, the buffer-access-fontify-functions
6812are not called. When called, these functions should put a non-nil
6813property on the text that they fontify, so that they won't get called
6814over and over for the same text.
6815
6816** Changes in lisp-mnt.el
6817
6818*** The lisp-mnt package can now recognize file headers that are written
6819in the formats used by the `what' command and the RCS `ident' command:
6820
6821;; @(#) HEADER: text
6822;; $HEADER: text $
6823
6824in addition to the normal
6825
6826;; HEADER: text
6827
6828*** The commands lm-verify and lm-synopsis are now interactive. lm-verify
6829checks that the library file has proper sections and headers, and
6830lm-synopsis extracts first line "synopsis'"information.
6831\f
6832* For older news, see the file ONEWS.
6833
6834----------------------------------------------------------------------
6835Copyright information:
6836
6837Copyright (C) 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
6838
6839 Permission is granted to anyone to make or distribute verbatim copies
6840 of this document as received, in any medium, provided that the
6841 copyright notice and this permission notice are preserved,
6842 thus giving the recipient permission to redistribute in turn.
6843
6844 Permission is granted to distribute modified versions
6845 of this document, or of portions of it,
6846 under the above conditions, provided also that they
6847 carry prominent notices stating who last changed them.
6848\f
6849Local variables:
6850mode: outline
6851paragraph-separate: "[ \f]*$"
6852end: