6 This file presents some general information about XEmacs. It is
7 primarily about the changes in recent XEmacs versions and its release
10 Use `C-c C-f' to move to the next equal level of outline, and
11 `C-c C-b' to move to previous equal level. `C-h m' will give more
12 info about the Outline mode. Many commands are also available through
15 Users who would like to know which capabilities have been introduced
16 in each release should look at the appropriate section of this file.
17 Starting with version 20.0, XEmacs includes ChangeLogs, which can be
18 consulted for a more detailed list of changes.
20 Users interested in some of the details of how XEmacs differs from GNU
21 Emacs should read the section "What's Different?" near the end of this
24 N.B. The term "GNU Emacs" refers to any release of Emacs Version
25 19 from the Free Software Foundation's GNU Project. (We do not
26 say just "Emacs" as Richard M. Stallman ["RMS"] prefers, because
27 it is clearly a more generic term.) The term "XEmacs" refers to
28 this program or to its predecessors "Era" and "Lucid Emacs". The
29 predecessor of all these program is called "Emacs 18". When no
30 particular version is implied, "Emacs" will be used.
33 * Changes in XEmacs 21.2
34 ========================
36 ** The delete key now deletes forward by default.
38 This is regulated by the variable `delete-key-deletes-forward', which
39 now defaults to t. `delete-key-deletes-forward' takes effect only on
40 the systems that offer both a backspace and a delete key. If set to
41 nil, the key labeled "Delete" will always delete backward. If set to
42 non-nil, the "Delete" key will delete forward, except on keyboards
43 where a "Backspace" key is not provided (e.g. old DEC keyboards.)
45 Unless our implementation has bugs, the only reason why you would want
46 to set `delete-key-deletes-forward' to nil is if you want to use the
47 Delete key to delete backwards, despite the presence (according to
48 Xlib) of a BackSpace key on the keyboard.
50 ** Interactive searching and matching case improvements.
52 Case sensitiveness in searching operations is normally controlled by
53 the variable `case-fold-search' (if non-nil, case is ignored while
54 searching). This mechanism has now been slightly improved for
55 interactive searches: if the search string (or regexp) contains
56 uppercase characters, the searching is forced to be case-sensitive,
59 The new behavior affects all functions performing interactive
60 searches, like `zap-to-char', `list-matching-lines', `tags-search'
61 etc. The incremental search facility has always behaved that way.
63 ** Incremental search will now highlight all visible matches, making
64 it easier to anticipate where consecutive C-s or C-r will place the
65 point. If you want to disable the feature, set
66 `isearch-highlight-all-matches' to nil.
68 ** You can now use the buffer tabs to switch between buffers. The
69 tabs are located between the toolbar and the uppermost window, in a
70 location called "gutter". If you dislike the buffer tabs, you can
71 disable them by specifying:
73 (set-specifier default-gutter-visible-p nil)
75 in your `.emacs'. You can change the location of the gutter with
76 `set-default-gutter-position', however currently only MS-Windows
77 supports tab widgets with orientations other than vertical..
79 ** When you press RET at a minibuffer prompt that provides a default
80 value, the value is stored in history instead of an empty line. Also,
81 you can now edit the default value by pressing the down arrow,
82 accessing the logical "future" value. Not all minibuffer prompts have
83 yet been converted to support this feature.
85 ** The rectangle functions have been almost completely rewritten in
86 order to avoid inserting undesirable spaces, notably at the end of
87 lines. Two typical examples of the old behavior were
88 `string-rectangle', which filled all lines up to the right side of the
89 rectangle, and `clear-rectangle', which filled even empty lines up to
90 the left side. All functions have been rewritten to avoid inserting
91 unwanted spaces, and an optional prefix now allows them to behave the
94 As a side effect, the FORCE argument to `move-to-column' now
95 understands the special value `coerce', which means that the line
96 should not be filled if it is too short to reach the desired column.
98 ** Customize now supports adding comments about your face and variable
99 settings using a new menu entry. Comments for variables can also be
100 assigned by calling `customize-set-(value|variable)' with a prefix
103 ** XEmacs now locates the early package hierarchies at
104 ~/.xemacs/mule-packages/ and ~/.xemacs/xemacs-packages/. Previously,
105 the early packages were located in ~/.xemacs/.
107 ** You can now create "indirect buffers", like in GNU Emacs. An
108 indirect buffer shares its text with another buffer ("base buffer"),
109 but has its own major mode, local variables, extents, and narrowing.
110 An indirect buffer has a name of its own, distinct from those of the
111 base buffer and all other buffers. An indirect buffer cannot itself
112 be visiting a file (though its base buffer can be). The base buffer
113 cannot itself be indirect.
115 Use (make-indirect-buffer BASE-BUFFER NAME) to make an indirect buffer
116 named NAME whose base is BASE-BUFFER. If BASE-BUFFER is itself an
117 indirect buffer, its base buffer is used as the base for the new
120 You can make an indirect buffer current, or switch to it in a window,
121 just as you would a non-indirect buffer.
123 The function `buffer-base-buffer' returns a buffer's base buffer or
124 nil, if given an ordinary (non-indirect) buffer. The function
125 `buffer-indirect-children' returns a list of the indirect children of
128 ** User names following the tilde character can now be completed at
129 file name prompts; e.g. `C-x C-f ~hni<TAB>' will complete to
130 `~hniksic/'. To make this operation faster, a cache of user names is
131 maintained internally.
133 The new primitives available for this purpose are functions named
134 `user-name-completion' and `user-name-all-completions'.
136 ** XEmacs can now play sound using Enlightenment Sound Daemon (ESD).
137 It will try NAS first, then ESD, then playing native sound directly.
139 ** X-Face support is now available under MS-Windows.
140 If an X-Face libary built under MS-Windows is available then XEmacs
141 will use this at build time.
143 ** The font-menu is now available under MS-Windows.
145 ** MS-Windows support for selection is now much more robust.
147 Generally selection should now do what you would expect under
148 MS-Windows: the middle mouse button will paste your current selection
149 or the clipboard; conversions from different types of selection to the
150 clipboard can be made; the kill-ring and friends will be updated as
153 The only thing selection doesn't do is set the clipboard automatically
154 as this would break the MS-Windows model. If you want this behaviour
155 then set `selection-sets-clipboard' to t
157 ** Mail spool locking now works correctly.
158 XEmacs has always come with a little auxiliary program, movemail,
159 which moves mail out of the system's spool area into user storage. To
160 coordinate between XEmacs, the mail delivery agent, and other mail
161 user agents, movemail needs to properly lock the spool file before
162 moving it. Movemail now correctly respects the --mail-locking option
163 to configure. Moreover, movemail's locking behavior can be specified
164 at run-time, via a new command-line option -m to movemail, or through
165 the environment variable EMACSLOCKMETHOD.
167 When installing XEmacs, make sure you configure it according to your
168 environment's mail spool locking conventions. When you're using a
169 binary kit, set the `mail-lock-method' variable at startup, or the
170 EMACSLOCKMETHOD environment variable.
172 ** New command-line switches -user-init-file and -user-init-directory.
173 These can be used to specify alternate locations for what is normally
174 ~/.emacs and ~/.xemacs.
176 Moreover, -user <user> (which used to only work in unpredictable ways)
178 -user-init-file ~<user>/.emacs -user-init-directory ~<user>/.xemacs.
180 ** New variable `mswindows-meta-activates-menu'.
181 If you set this variable to nil then pressing the Alt key under
182 MS-Windows will no longer activate the menubar. The default is t.
184 ** Pixel-based scrolling has been implemented.
185 By default this will attempt to scroll in increments equal to the
186 height of the default face. Set `window-pixel-scroll-increment' to
187 modify this behaviour.
191 *** In DOS, etags looks for file.cgz if it cannot find file.c.
193 *** New option --ignore-case-regex is an alternative to --regex. It is now
194 possible to bind a regexp to a language, by prepending the regexp with
195 {lang}, where lang is one of the languages that `etags --help' prints
196 out. This feature is useful especially for regex files, where each
197 line contains a regular expression. The manual contains details.
199 *** In C and derived languages, etags creates tags for function
200 declarations when given the --declarations option.
202 *** In C++, tags are created for "operator". The tags have the form
203 "operator+", without spaces between the keyword and the operator.
205 *** New language Ada: tags are functions, procedures, packages, tasks, and
208 *** In Fortran, procedure is no more tagged.
210 *** In Java, tags are created for "interface".
212 *** In Lisp, "(defstruct (foo", "(defun (operator" and similar constructs
215 *** In Perl, the --globals option tags global variables. my and local
216 variables are tagged.
218 *** New language Python: def and class at the beginning of a line are tags.
220 *** .ss files are Scheme files, .pdb is Postscript with C syntax, .psw is
224 * Lisp and internal changes in XEmacs 21.2
225 ==========================================
227 ** A new portable dumper is available for beta testing.
229 Olivier Galibert has written a portable dumper for XEmacs, based on
230 initial work by Kyle Jones. Normally, XEmacs C sources link into an
231 executable called `temacs', which loads the Lisp code and "unexecs"
232 into a proper `xemacs' executable. The unexec() process is hard to
233 implement correctly and makes XEmacs very hard to port to new
234 operating systems, or even to new releases of old systems.
236 A portable dumper is a different approach to dumping: instead of
237 dumping full-fledged executable, it only dumps out the initialized
238 data structures (both Lisp and C) into an external file. A normally
239 running XEmacs only needs to mmap() that file and relocate a bit to
240 get to the initialized data. In that scheme, there is no difference
241 between `temacs' and `xemacs'.
243 This is all very experimental, though. Configure with `--pdump' to
244 try testing it. NOTE: it is expected that `make' will fail after
245 dumping `xemacs.dmp'. This is because Makefiles have not yet been
246 modified to not expect `temacs' producing an `xemacs' executable. You
247 can try it out by simply running `src/temacs'. If it starts without
248 failure, the portable dumping worked.
250 #### NOTE: the portable dumper is not really usable yet, because the
251 state of built-in variables is not yet saved. Olivier promised to fix
254 ** Much effort has been invested to make XEmacs Lisp faster:
256 *** Many basic lisp operations are now faster.
257 This is especially the case when running a Mule-enabled XEmacs.
259 A general overhaul of the lisp engine should produce a speedup of 1.4
260 in a Latin-1 XEmacs, and 2.1 in a Mule XEmacs. These numbers were
261 obtained running `(byte-compile "simple.el")', which should be a
262 pretty typical test of "pure" Lisp.
264 *** Lisp hash tables have been re-implemented. The Common Lisp style
265 hash table interface has been made standard, and moved from cl.el into
266 fast C code (See the section on hash tables in the XEmacs Lisp
267 Reference). A speedup factor of 3 can be expected with code that
268 makes intensive use of hash tables.
270 *** The garbage collector has been tuned, leading to a speedup of
273 *** The family of functions that iterate over lists, like `memq', and
274 `rassq', have been made a little faster (typically 1.3).
276 *** Lisp function calls are faster, by approximately a factor of two.
277 However, defining inline functions (via defsubst) still makes sense
280 *** Finally, a few functions have had dramatic performance
281 improvements. For example, `(last long-list)' is now 30 times faster.
283 Of course, your mileage will vary.
285 Many operations do not see any improvement. Surprisingly, running
286 (font-lock-fontify-buffer) does not use the Lisp engine much at all.
287 Speeding up your favorite slow operation is an excellent project to
288 improve XEmacs. Don't forget to profile!
290 ** Native widgets can be displayed in buffers.
292 The glyph system has been extended to allow the display of glyphs that
293 are implemented as native window-system widgets. Thus you can embed
294 buttons, scrollbars, combo boxes, edit fields and progress gauges in a
295 buffer. As a side effect subwindow support now works once again.
297 All of this is still fairly experimental and there is no
298 documentation. The current APIs might change in a future version of
299 XEmacs. Some widgets are only available under MS-Windows. See the
300 file glyphs-test.el in the XEmacs src distribution for examples of
303 The buffers-tab functionality and progress gauge have been implemented
306 ** `user-init-file' and `user-init-directory' are now absolute
307 file/directory names. Previously, both variables used to be relative
308 to (concat "~" init-file-user). This turned out to be too complicated
309 for most packages (and some core Lisp files) to use correctly. Also,
310 the `init-file-user' variable has been obsoleted in the process.
312 The user-visible options like `-u' have not changed their behaviour.
314 ** XEmacs finally has an automated test suite!
315 Although this is not yet very sophisticated, it is already responsible
316 for several important bug fixes in XEmacs. To try it out, simply use
317 the makefile target `make check' after building XEmacs.
319 ** Hash tables have been reimplemented.
320 As was pointed out above, the standard interface to hash tables is now
321 the Common Lisp interface, as described in Common Lisp, the Language
322 (CLtL2, by Steele). The older interface (functions with names
323 containing the phrase `hashtable') will continue to work, but the
324 preferred interface now has names containing the phrase `hash-table'.
326 Here's the executive overview: create hash tables using
327 make-hash-table, and use gethash, puthash, remhash, maphash and
328 clrhash to manipulate entries in the hash table. See the (updated)
329 Lisp Reference Manual for details.
331 ** Lisp code handles circular lists much more robustly.
332 Many basic lisp functions used to loop forever when given a circular
333 list, expecting you to C-g (quit) out of the loop. Now this is more
334 likely to trigger a `circular-list' error. Printing a circular list
335 now results in something like this:
337 (let ((x (cons 'foo 'foo)))
340 => (foo ... <circular list>)
342 An extra bonus is that checking for circularities is not just
343 friendlier, but actually faster than checking for C-g.
345 ** Functions for decoding base64 encoding are now available; see
346 `base64-encode-region', `base64-encode-string', `base64-decode-region'
347 and `base64-decode-string'.
349 ** The functions `read-string', `read-expression', `eval-minibuffer',
350 `read-variable', `read-command', `read-function', `read-number',
351 `read-shell-command', `read-from-minibuffer', and `completing-read'
352 now take an additional argument which specifies the default value. If
353 this argument is non-nil, it should be a string; that string is used
356 It is returned if the user enters empty input.
357 It is available through the history command M-n.
361 *** The LDAP interface now consists of two layers, a low-level layer
362 that closely matches the LDAP C API, and a more convenient
363 higher-level set of functions.
365 *** The low-level functions that used to be named *-internal are now
366 named more simply: `ldap-open', `ldap-close', `ldap-search-basic',
367 `ldap-add', and `ldap-modify'. They should be used directly for very
368 specific purposes (such as multiple operations on a connection) only.
370 *** The higher-level functions provide a more convenient way to access
371 LDAP directories hiding the subtleties of handling the connection,
372 translating arguments and ensuring compliance with LDAP
373 internationalization rules and formats (currently partly implemented
374 only.) This layer provides atomic operations for searches,
375 modification, addition and deletion of multiple entries at once:
376 `ldap-search-entries', `ldap-add-entries', `ldap-delete-entries', and
377 `ldap-modify-entries'.
379 *** To maintain compatibility with previous code, the now obsolete
380 function `ldap-search' is now merely a wrapper that calls either
381 `ldap-search-basic' or `ldap-search-entries'. Please don't use the
382 `ldap-search' function in your new programs -- a direct call to one of
383 the two replacements is more efficient and unambiguous.
385 ** The arguments to `locate-file' are now more Lisp-like. As before,
388 (locate-file FILENAME PATH-LIST &optional SUFFIXES MODE)
390 Except that SUFFIXES are now a list of strings instead of a single,
391 colon-separated string. MODE is now a symbol or a list of symbols
392 (symbols `exists', `executable', `writable', and `readable' are
393 supported) instead of an integer code. See the documentation for
394 details. Of course, the old form is still accepted for backward
397 Several bugs in locate-file have been fixed, most notably its failure
398 to call expand-file-name on elements of PATH-LIST. Because of that
399 elements of load-path of the form "~/..." used to not work.
400 locate-file is now guaranteed to expand files during its course of
403 ** `translate-region' has been improved in several ways. Its TABLE
404 argument used to be a 256-character string. In addition to this, it
405 can now also be a vector or a char-table, which makes the function
406 useful for Mule, which it wasn't. If TABLE a vector or a generic
407 char-table, you can map characters to strings instead of to other
408 characters. For instance:
410 (let ((table (make-char-table 'generic)))
411 (put-char-table ?a "the letter a" table)
412 (put-char-table ?b "" table)
413 (put-char-table ?c ?\n table)
414 (translate-region (point-min) (point-max) table))
416 ** The new form `ignore-file-errors', similar to `ignore-errors' may
417 be used as a short-hand for condition-case when you wish to ignore
418 file-related error. For example:
420 (ignore-file-errors (delete-file "foo"))
422 ** The first argument to `intern-soft' may now also be a symbol, like
423 with `unintern'. If given a symbol, `intern-soft' will look for that
424 exact symbol rather than for any string. This is useful when you want
425 to check whether a specific symbol is interned in an obarray, e.g.:
430 (intern-soft (make-symbol "foo"))
433 ** The `keywordp' function now returns non-nil only on symbols
434 interned in the global obarray. For example:
436 (keywordp (intern ":foo" [0]))
438 (keywordp (intern ":foo")) ; The same as (keywordp :foo)
441 This behaviour is compatible with other code which treats symbols
442 beginning with colon as keywords only if they are interned in the
443 global obarray. `keywordp' used to wrongly return t in both cases
447 * Changes in XEmacs 21.0
448 ========================
450 ** XEmacs has been unbundled into constituent installable packages.
451 See the Info documentation under "Packages" for more information.
452 See the file `etc/PACKAGES' in the distribution for a partial list of
453 packages available at the time of the 21.0 release.
455 ** XEmacs is now supported under Microsoft Windows 95/98 and Windows
456 NT operating systems. For starters, look at the XEmacs on Windows FAQ
457 at <URL:http://jagor.srce.hr/~hniksic/xemacs-on-windows-faq.txt>. To
458 discuss Windows-specific issues, subscribe to the mailing list at
459 <xemacs-nt-request@xemacs.org>.
461 ** XEmacs will now use `XEmacs' as its application class if it finds
462 any `XEmacs' resources in the resource database. Otherwise, it will
463 continue to use the `Emacs' class.
465 ** The options menu has been ported to Custom.
466 This means that each entry in the options menu acts as if you had customized
467 the corresponding variable by hand. ### WARNING: there is currently no
468 upgrading function to help you port your old options settings to the new
469 format. Consequently, if you want to modify the options for XEmacs 21, you
470 will have to set them all again through the menu, and remove the code loading
471 .xemacs-options from your .emacs.
473 ** When the Zmacs region is active, `M-x query-replace' and the other
474 replace commands now operate on the region contents only.
476 ** XEmacs now is able to choose X visuals and use private colormaps.
477 The '-visual <visualStr>' command line option or the '.EmacsVisual'
478 Xresource controls which visual XEmacs will use, and
479 '-privateColormap' or '.privateColormap' will force XEmacs to create a
480 private colormap for use. The syntax for the visual string is
481 "<visual><bitdepth>" where <visual> is one of 'StaticColor',
482 'TrueColor', 'GrayScale', 'PseudoColor' or 'DirectColor' and
483 <bitdepth> is the appropriate number of bits per pixel. If an invalid
484 or non-supported combination is entered, XEmacs attempts to find a happy
485 medium. The X creation mechanism will then determine if it needs to
486 create a colormap for use, or the presence of the private flags will
487 force it to create it.
489 ** The `imenu' package has been ported to XEmacs and is available as a
492 ** `echo-keystrokes' can now be a floating-point number, so that you
493 can set it to intervals shorter than one second.
495 (setq echo-keystrokes 0.1)
497 ** The new command `center-to-window-line' works like `recenter'
498 (bound to `C-l'), only it does not redisplay the whole display area.
500 ** The M-. command will now first search through exact tags matches,
501 and then through inexact matches, as one would expect.
503 ** The new variable `user-full-name' can be used to customize one's
504 name when using the Emacs mail and news reading facilities.
506 Normally, `user-full-name' is a function that returns the full name of
507 a user or UID, as specified by the system -- for instance,
508 (user-full-name "root") returns something like "Super-User". However,
509 when the function is called without arguments, it will return the
510 value of the `user-full-name' variable. The `user-full-name' variable
511 is initialized using the environment variable NAME and (failing that)
512 the user's system name.
514 The behavior of the `user-full-name' function with an argument
515 specified is unchanged.
517 ** The new command `M-x customize-changed-options' lets you customize
518 all the options whose default values have changed in recent Emacs
519 versions. You specify a previous Emacs version number as argument,
520 and the command creates a customization buffer showing all the
521 customizable options whose default values were changed since that
524 If you don't specify a particular version number argument, then the
525 customization buffer shows all the customizable options for which
526 Emacs versions of changes are recorded.
528 ** The new command `add-log-convert' can be used to convert the
529 old-style (pre-20.3) ChangeLog buffers to new style, for
530 consistency. A reminder: if you wish to revert to old-style
531 ChangeLogs instead, customize the value of `add-log-time-format'
534 ** The new command `zap-up-to-char' is now available. It is similar
535 to `zap-to-char', except that it does not delete the searched-for
536 character. It is not bound to a key by default.
538 ** You can now store a number into a register with `C-u NUMBER C-x r n'
539 REG, increment it by INC with `C-u INC C-x r + REG' (to increment by
540 one, omit C-u INC), and insert it in the buffer with `C-x r g REG'.
541 This is useful for writing keyboard macros.
543 ** The M-: command, when given a prefix argument, will now insert its
544 result to the current buffer.
546 ** The `C-h c' command, when given a prefix argument, will now insert
547 the message into the current buffer.
549 ** Horizontally split windows may now be dragged using the mouse.
550 Because of this, the dividers between vertical windows are always
551 visible. To turn it off, set `vertical-divider-always-visible-p' to
554 ** XEmacs/Mule (internationalization) changes.
556 *** Mule support now works on TTY's. Use `set-terminal-coding-system'
557 and `set-keyboard-coding-system' to specify the coding system of your
558 display and keyboard.
560 *** Egg/SJ3 input method is now officially supported. Quail and
561 Egg/Skk have been available through the generalized Leim since 20.3.
563 *** Localized Japanese menubars are available if XEmacs is built with
564 XFONTSET and either the X11 libraries are built with X_LOCALE defined
565 or the native C libraries support Japanese localization. This has
566 been available since 20.3, only it hasn't been announced before.
568 ** Jamie Zawinski's `gdb-highlight' extension is now distributed with
569 the `debug' package. gdb-highlight makes most objects printed in a
570 gdb buffer be mouse-sensitive: as text shows up in the buffer, it is
571 parsed, and objects which are recognized have context-sensitive
572 commands attached to them. To use it, add the following to `.emacs':
574 (add-hook 'gdb-mode-hook (lambda () (require 'gdb-highlight)))
576 ** The package popper.el is now included in the edit-utils package.
577 It has been greatly enhanced with respect to the one once included
578 with the ilisp package and should work well under XEmacs 21.0.
582 *** Like the old 'gnudoit' program. Gnuclient -batch now can read from stdin.
584 *** Gnuclient -batch no longer breaks off the output at the first LF.
588 *** Multiline macros are now handled, both as they affect indentation,
589 and as recognized syntax. New syntactic symbol cpp-macro-cont is
590 assigned to second and subsequent lines of a multiline macro
593 *** A new style "user" which captures all non-hook-ified
594 (i.e. top-level) .emacs file variable setings and customizations.
595 Style "cc-mode" is an alias for "user" and is deprecated. "gnu" style
596 is still the default however.
598 *** "java" style now conforms to Sun's JDK coding style.
600 *** There are new commands c-beginning-of-defun, c-end-of-defun which
601 are alternatives which you could bind to C-M-a and C-M-e if you prefer
602 them. They do not have key bindings by default.
604 *** New and improved implementations of M-a (c-beginning-of-statement)
605 and M-e (c-end-of-statement).
607 *** C++ namespace blocks are supported, with new syntactic symbols
608 namespace-open, namespace-close, and innamespace.
610 *** File local variable settings of c-file-style and c-file-offsets
611 makes the style variables local to that buffer only.
613 *** New indentation functions c-lineup-close-paren,
614 c-indent-one-line-block, c-lineup-dont-change.
616 *** Improvements (hopefully!) to the way CC Mode is loaded. You
617 should now be able to do a (require 'cc-mode) to get the entire
618 package loaded properly for customization in your .emacs file. A new
619 variable c-initialize-on-load controls this and is t by default.
621 ** In Text mode, now only blank lines separate paragraphs.
622 This makes it possible to get the full benefit of Adaptive Fill mode
623 in Text mode, and other modes derived from it (such as Mail mode).
624 TAB in Text mode now runs the command indent-relative; this makes a
625 practical difference only when you use indented paragraphs.
627 As a result, the old Indented Text mode is now identical to Text mode,
628 and is an alias for it.
630 If you want spaces at the beginning of a line to start a paragraph,
631 use the new mode, Paragraph Indent Text mode.
633 ** Changes to Gnus, the XEmacs newsreader.
635 *** New functionality for using Gnus as an offline newsreader has been
636 added. A plethora of new commands and modes have been added. See the
637 Gnus manual for the full story.
639 *** The nndraft backend has returned, but works differently than
640 before. All Message buffers are now also articles in the nndraft
641 group, which is created automatically.
643 *** `gnus-alter-header-function' can now be used to alter header
646 *** `gnus-summary-goto-article' now accept Message-ID's.
648 *** A new Message command for deleting text in the body of a message
649 outside the region: `C-c C-v'.
651 *** You can now post to component group in nnvirtual groups with
654 *** `nntp-rlogin-program' -- new variable to ease customization.
656 *** `C-u C-c C-c' in `gnus-article-edit-mode' will now inhibit
657 re-highlighting of the article buffer.
659 *** New element in `gnus-boring-article-headers' -- `long-to'.
661 *** `M-i' symbolic prefix command. See the section "Symbolic
662 Prefixes" in the Gnus manual for details.
664 *** `L' and `I' in the summary buffer now take the symbolic prefix
665 `a' to add the score rule to the "all.SCORE" file.
667 *** `gnus-simplify-subject-functions' variable to allow greater
668 control over simplification.
670 *** `A T' -- new command for fetching the current thread.
672 *** `/ T' -- new command for including the current thread in the
675 *** `M-RET' is a new Message command for breaking cited text.
677 *** \\1-expressions are now valid in `nnmail-split-methods'.
679 *** The `custom-face-lookup' function has been removed.
680 If you used this function in your initialization files, you must
681 rewrite them to use `face-spec-set' instead.
683 *** Cancelling now uses the current select method. Symbolic prefix
684 `a' forces normal posting method.
686 *** New command to translate M******** sm*rtq**t*s into proper text
689 *** For easier debugging of nntp, you can set `nntp-record-commands'
692 *** nntp now uses ~/.authinfo, a .netrc-like file, for controlling
693 where and how to send AUTHINFO to NNTP servers.
695 *** A command for editing group parameters from the summary buffer
698 *** A history of where mails have been split is available.
700 *** A new article date command has been added -- `article-date-iso8601'.
702 *** Subjects can be simplified when threading by setting
703 `gnus-score-thread-simplify'.
705 *** A new function for citing in Message has been added --
706 `message-cite-original-without-signature'.
708 *** `article-strip-all-blank-lines' -- new article command.
710 *** A new Message command to kill to the end of the article has
713 *** A minimum adaptive score can be specified by using the
714 `gnus-adaptive-word-minimum' variable.
716 *** The "lapsed date" article header can be kept continually
717 updated by the `gnus-start-date-timer' command.
719 *** Web listserv archives can be read with the nnlistserv backend.
721 *** Old dejanews archives can now be read by nnweb.
723 *** Byte-compilation of user-specs now works under XEmacs.
725 ** The `dir' files are no longer essential for functioning of the Info
726 subsystem. If the `dir' file does not exist in an Info directory, the
727 relevant information will be generated on-the-fly.
729 This behavior can be customized, look for `Info-auto-generate-directory'
730 and `Info-save-auto-generated-dir' in the `info' customization group.
733 * Lisp and internal changes in XEmacs 21.0
734 ==========================================
736 ** It is now possible to build XEmacs with support for 31-bit Lisp
737 integers (normally, Lisp integers are only 28 bits wide on 32-bit
738 machines.) Configure with --use-minimal-tagbits to test. With this
739 change, the maximum buffer size on 32-bit machines is increased from
740 128M to 1G. This setting will be made default in a future XEmacs
743 ** Specifier changes.
745 *** When instantiating a specifier, the window locale now has a higher
746 precedence than the buffer locale. This is because the window locale
747 is more specific than the buffer locale.
749 *** The new macro `let-specifier' can be used to temporarily add
750 specifications to specifiers. See the documentation for details.
752 *** The new specifiers `vertical-scrollbar-visible-p' and
753 `horizontal-scrollbar-visible-p' may be used to control scrollbar
754 visibility. Previously, the only way to remove a scrollbar was to set
755 its size to 0. This method is still supported for backward
758 *** The new specifiers `scrollbar-on-left-p' and `scrollbar-on-top-p'
759 may be used to control the position of the vertical and horizontal
760 toolbar. Previously, their position could be changed only through the
763 *** The new draggable vertical dividers between windows may be turned
764 off using the `vertical-divider-always-visible-p' specifier. When
765 this is set to nil, the vertical dividers between windows are shown
766 only when needed, and they are not draggable.
768 Other properties of the vertical dividers may be controlled using
769 `vertical-divider-shadow-thickness', `vertical-divider-line-width' and
770 `vertical-divider-spacing' specifiers, which see.
772 ** Frame focus management changes.
774 *** When the variable focus-follows-mouse is non-nil, `select-frame'
775 no longer permanently selects a different frame. The frame selection
776 is temporary and is reverted when the current command terminates, much
777 like the buffer selected by `set-buffer'. This is the same as in FSF
780 *** The new function `focus-frame' sets the window system focus to
781 FRAME (and selects it), regardless of the value of
782 `focus-follows-mouse'. Doing this is not well behaved, so be
783 absolutely sure that you want this.
785 The code that uses `select-frame' only to get the window manager focus
786 should be changed to use `set-frame-focus' instead, so that they keep
787 working when `focus-follows-mouse' is non-nil.
789 *** The special forms `save-selected-frame' and `with-selected-frame'
790 can now be used to temporarily change selected frame.
792 *** The behavior of `other-frame' command (`C-x 5 o') is unaffected by
795 ** The function `select-window' now has an optional second argument
796 NORECORD which if non-nil inhibits the recording of a buffer change.
798 ** The function `vertical-motion' now correctly handles the second,
799 optional WINDOW argument. A new third argument PIXELS, if non-nil,
800 indicates that the returned motion should be in pixels.
802 ** The new function `vertical-motion-pixels' is similar to
803 vertical-motion but takes as input a vertical motion in pixels.
805 ** The new functions window-text-area-pixel-{width,height,edges} can
806 be used to obtain information about the text-displaying area of a
809 ** The new functions `shrink-window-pixels' and `enlarge-window-pixels'
810 can be used to adjust the size of a window by a pixel amount.
812 ** The new function `window-displayed-text-pixel-height' can be used
813 to determine the height of the text actually displayed in a window.
815 ** The arithmetic comparison functions <, >, =, /= now accept a
816 variable number of arguments.
818 This means that if you want to test whether A < B < C, you can write
819 it as (< A B C) instead of (and (< A B) (< B C)). Likewise,
820 (apply #'> LIST) now tests if LIST is monotonously increasing -- and
823 ** The XEmacs hashtables now have a consistent read/print syntax.
824 This means that a hashtable will be readably printed in a
827 #s(hashtable size 2 data (key1 value1 key2 value2))
829 When XEmacs reads this form, it will create a new hashtable according
830 to description. This allows you to easily dump hashtables to files
831 using `prin1', and read them back in using `read'.
833 If `print-readably' is non-nil, a more relaxed syntax is used; for
836 #<hashtable size 2/13 data (key1 value1 key2 value2) 0x874d>
838 ** It is now possible to build XEmacs with LDAP support.
839 You will need to install a LDAP library first. The following have
841 - LDAP 3.3 from the University of Michigan
842 (get it from <URL:http://www.umich.edu/~dirsvcs/ldap/>)
843 - OpenLDAP 1.0.3 from the OpenLDAP Foundation
844 (get it from <URL:http://www.openldap.org/>)
845 - LDAP SDK 1.0 from Netscape Corp.
846 (get it from <URL:http://developer.netscape.com/>)
848 ** When profiling is in effect, a call-count of all recorded functions
849 is now calculated. This information is stored in
850 `call-count-profile-table', and is utilized by `profile-results' as
851 well as the new command `profile-call-count-results'.
853 ** It is now an error to change the value of a symbol whose name
854 starts with a colon, if it is interned in the standard obarray.
856 However, setting such a symbol to its proper value, which is that
857 symbol itself, is not an error. This is for the sake of programs that
858 support pre-19.12 XEmacs and pre-20 GNU Emacs by explicitly setting
859 these variables to themselves.
861 ** The `concat' function no longer accepts integer arguments.
863 ** The new function `string' concatenates all its argument characters
864 and returns the resulting string. This is consistent with other
865 functions, like `list', `vector', etc.
867 ** The function `temp-directory' is now available to return the
868 directory to store temporary files. On Unix this will be obtained
869 from TMPDIR, defaulting to `/tmp'.
871 ** The function load-average now accepts an optional argument
872 USE-FLOATS. If it is non-nil, the load average values are returned as
873 floating point numbers, rather than as integers to be divided by 100.
875 ** The `make-event' function now supports the TYPE and PLIST
876 arguments, which can be used to create various events from Lisp. See
877 the documentation for details.
879 ** `function-interactive' is a new function that returns the
880 interactive specification of a funcallable object.
882 ** The new `lmessage' function allows printing of a formatted message
883 with a particular label.
885 (lmessage 'progress "Processing... %d" counter)
887 This function is more convenient than `display-message' because it
888 automatically applies `format' to its arguments.
890 ** The new `lwarn' function, analogous to `lmessage', allows printing
891 a formatted warning, with a non-default CLASS or LABEL.
893 ** The new function `split-path' can now be used to explode the
894 components of a colon-separated search path into a list.
896 (split-path "foo:bar")
899 ** Specifiers and symbols whose value is a specifier are now allowed
900 as modeline specifications.
902 ** defcustom now accepts the keyword `:version'. Use this to specify
903 in which version of Emacs a certain variable's default value changed.
906 (defcustom foo-max 34 "*Maximum number of foo's allowed."
911 This information is used to control the customize-changed-options
914 ** The line number tracking in modeline is now efficient, even for
915 very large buffers. This is achieved by caching the line numbers of
916 recent buffer positions, and reusing them. This cache is used only in
917 the buffers where `line-number-mode' is in effect.
919 ** When the new GNU Malloc aka Doug Lea Malloc is available, it will
920 be used. This should result in better performance on Linux systems
923 ** The code XEmacs uses to assemble its various paths into the
924 directory hierarchy has been rewritten to support the package system.
925 Look under "Startup Paths" in the Info documentation for more
928 *** site-lisp is no longer part of the load-path by default.
929 Its use is deprecated, but you can specify --with-site-lisp=yes at the
930 configure command line to get it back.
932 *** `Info-default-directory-list' is now obsolete. If you want to
933 change the path which XEmacs uses to search for info files, set
934 `Info-directory-list' instead.