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 ** Shifted motion keys now select text by default. You can turn this
51 off by setting `shifted-motion-keys-select-region' to nil.
53 ** You can now set the variable `kill-whole-line' to `always', which
54 makes `kill-line' (C-k) delete the entire line always, not just when
55 the cursor is at the beginning of the line. This behavior, as well as
56 the existing kill-whole-line behavior, now only take effect when
57 kill-line is called interactively, although this is a departure from a
58 previous behavior in the case of setting this variable kill-whole-line
59 to t. It is almost certainly what has always been intended, and most
60 likely the old way of doing things introduced bugs.
62 The new function `historical-kill-line' ignores the `kill-whole-line'
63 setting and always gives the historical behavior of only killing to
64 the end of the line. This function is bound to Sh-C-k, so that the
65 kill to end of line behavior is available, even when `kill-whole-line'
68 ** XEmacs menus now have accelerators by default. If a menu item does
69 not have an accelerator specified, one is created dynamically, using
70 numbers 1-9 and letters.
72 ** Interactive searching and matching case improvements.
74 Case sensitiveness in searching operations is normally controlled by
75 the variable `case-fold-search' (if non-nil, case is ignored while
76 searching). This mechanism has now been slightly improved for
77 interactive searches: if the search string (or regexp) contains
78 uppercase characters, the searching is forced to be case-sensitive,
81 The new behavior affects all functions performing interactive
82 searches, like `zap-to-char', `list-matching-lines', `tags-search'
83 etc. The incremental search facility has always behaved that way.
85 ** Incremental search will now highlight all visible matches, making
86 it easier to anticipate where consecutive C-s or C-r will place the
87 point. If you want to disable the feature, set
88 `isearch-highlight-all-matches' to nil.
90 ** You can now use the buffer tabs to switch between buffers. The
91 tabs are located between the toolbar and the uppermost window, in a
92 location called "gutter". If you dislike the buffer tabs, you can
93 disable them by customizing `gutter-buffers-tab-visible-p', or by
94 placing this in your .emacs:
96 (set-gutter-element-visible-p default-gutter-visible-p 'buffers-tab nil)
98 You can change the location of the gutter with
99 `set-default-gutter-position', however currently only MS-Windows
100 supports tab widgets with orientations other than vertical.
102 ** Kill and yank now interact with the clipboard by default under
103 Windows. This was done by changing the default value of
104 `interprogram-cut-function' and `interprogram-paste-function'. You
105 can get the old behavior by setting these to nil, and there is an
106 option on the options menu to do this.
108 ** When you press RET at a minibuffer prompt that provides a default
109 value, the value is stored in history instead of an empty line. Also,
110 you can now edit the default value by pressing the down arrow,
111 accessing the logical "future" value. Not all minibuffer prompts have
112 yet been converted to support this feature.
114 ** The rectangle functions have been almost completely rewritten in
115 order to avoid inserting undesirable spaces, notably at the end of
116 lines. Two typical examples of the old behavior were
117 `string-rectangle', which filled all lines up to the right side of the
118 rectangle, and `clear-rectangle', which filled even empty lines up to
119 the left side. All functions have been rewritten to avoid inserting
120 unwanted spaces, and an optional prefix now allows them to behave the
123 Also, the behavior of `string-rectangle' is now compliant with
124 `pending-delete-mode': if this mode is active, then the string
125 replaces the region rectangle. Otherwise, the command does not delete
126 or overwrite any existing text. For those who want that feature but do
127 not use pending-delete-mode, a new function, `replace-rectangle', is
130 As a side effect, the FORCE argument to `move-to-column' now
131 understands the special value `coerce', which means that the line
132 should not be filled if it is too short to reach the desired column.
134 ** Customize now supports adding comments about your face and variable
135 settings using a new menu entry. Comments for variables can also be
136 assigned by calling `customize-set-(value|variable)' with a prefix
139 ** XEmacs now locates the early package hierarchies at
140 ~/.xemacs/mule-packages/ and ~/.xemacs/xemacs-packages/. Previously,
141 the early packages were located in ~/.xemacs/.
143 ** You can now create "indirect buffers", like in GNU Emacs. An
144 indirect buffer shares its text with another buffer ("base buffer"),
145 but has its own major mode, local variables, extents, and narrowing.
146 An indirect buffer has a name of its own, distinct from those of the
147 base buffer and all other buffers. An indirect buffer cannot itself
148 be visiting a file (though its base buffer can be). The base buffer
149 cannot itself be indirect.
151 Use (make-indirect-buffer BASE-BUFFER NAME) to make an indirect buffer
152 named NAME whose base is BASE-BUFFER. If BASE-BUFFER is itself an
153 indirect buffer, its base buffer is used as the base for the new
156 You can make an indirect buffer current, or switch to it in a window,
157 just as you would a non-indirect buffer.
159 The function `buffer-base-buffer' returns a buffer's base buffer or
160 nil, if given an ordinary (non-indirect) buffer. The function
161 `buffer-indirect-children' returns a list of the indirect children of
164 ** User names following the tilde character can now be completed at
165 file name prompts; e.g. `C-x C-f ~hni<TAB>' will complete to
166 `~hniksic/'. To make this operation faster, a cache of user names is
167 maintained internally.
169 The new primitives available for this purpose are functions named
170 `user-name-completion' and `user-name-all-completions'.
172 ** XEmacs can now play sound using Enlightenment Sound Daemon (ESD).
173 It will try NAS first, then ESD, then playing native sound directly.
175 ** X-Face support is now available under MS-Windows.
176 If an X-Face libary built under MS-Windows is available then XEmacs
177 will use this at build time.
179 ** The font-menu is now available under MS-Windows.
181 ** MS-Windows support for selection is now much more robust.
183 Generally selection should now do what you would expect under
184 MS-Windows: the middle mouse button will paste your current selection
185 or the clipboard; conversions from different types of selection to the
186 clipboard can be made; the kill-ring and friends will be updated as
189 The only thing selection doesn't do is set the clipboard automatically
190 as this would break the MS-Windows model. If you want this behavior
191 then set `selection-sets-clipboard' to t.
193 ** Mail spool locking now works correctly.
194 XEmacs has always come with a little auxiliary program, movemail,
195 which moves mail out of the system's spool area into user storage. To
196 coordinate between XEmacs, the mail delivery agent, and other mail
197 user agents, movemail needs to properly lock the spool file before
198 moving it. Movemail now correctly respects the --mail-locking option
199 to configure. Moreover, movemail's locking behavior can be specified
200 at run-time, via a new command-line option -m to movemail, or through
201 the environment variable EMACSLOCKMETHOD.
203 When installing XEmacs, make sure you configure it according to your
204 environment's mail spool locking conventions. When you're using a
205 binary kit, set the `mail-lock-method' variable at startup, or the
206 EMACSLOCKMETHOD environment variable.
208 ** Init file will move to ~/.xemacs/init.el.
210 If `~/.xemacs/init.el' exists, XEmacs will prefer it over `~/.emacs'
211 as an init file. The file may be byte-compiled as
212 `~/.xemacs/init.elc'.
214 Future versions of XEmacs will stop supporting `~/.emacs' as an init
215 file. XEmacs offers automatic migration upon startup.
217 ** Custom file will move to ~/.xemacs/custom.el.
219 Whereas customize settings were formerly stored in the regular init
220 file, XEmacs now prefers them to be in a separate file
221 `~/.xemacs/custom.el', completely under automatic control. This
222 change goes with the migration of the init file, and XEmacs offers
223 automatic migration upon startup.
225 ** Init file may be called .emacs.el.
227 For the time being, like in GNU Emacs 20.4 and on, you can now name
228 the XEmacs init file `.emacs.el'. Formerly the name had to be
229 `.emacs'. If you use the name `.emacs.el', you can byte-compile the
230 file in the usual way.
232 If both `.emacs' and `.emacs.el' exist, the latter file is the one
235 ** New command-line switches -user-init-file and -user-init-directory.
236 These can be used to specify alternate locations for what is normally
237 ~/.emacs and ~/.xemacs.
239 Moreover, -user <user> (which used to only work in unpredictable ways)
240 is now equivalent to -user-init-file ~<user>/.xemacs/init.el
241 -user-init-directory ~<user>/.xemacs. or -user-init-file
242 ~<user>/.emacs -user-init-directory ~<user>/.xemacs, whichever init
245 ** New variable `mswindows-meta-activates-menu'.
246 If you set this variable to nil then pressing and releasing the Alt
247 key under MS-Windows will no longer activate the menubar. The default
248 is t. This is not to be confused with `menu-accelerator-enabled',
249 which enables the use of Alt+<Letter> accelerators to invoke the
252 ** Pixel-based scrolling has been implemented.
253 By default this will attempt to scroll in increments equal to the
254 height of the default face. Set `window-pixel-scroll-increment' to
255 modify this behavior.
257 ** Operation progress can be displayed using graphical widgets.
258 See `progress-feedback' for details. This support has been switched
259 on by default for font-lock and some web browsing functions. If you
260 do not like this behavior set `progress-feedback-use-echo-area'.
262 ** The PostgreSQL Relational Database Management System is now supported.
263 It is now possible to build XEmacs so that the programming interface
264 to the PostgreSQL RDBMS (libpq) is available in XEmacs Lisp.
265 Supported versions of PostgreSQL are 6.5.3 (earlier versions may work,
266 but have not been tested) and 7.0-beta1.
270 *** In DOS, etags looks for file.cgz if it cannot find file.c.
272 *** New option --ignore-case-regex is an alternative to --regex. It is now
273 possible to bind a regexp to a language, by prepending the regexp with
274 {lang}, where lang is one of the languages that `etags --help' prints
275 out. This feature is useful especially for regex files, where each
276 line contains a regular expression. The manual contains details.
278 *** In C and derived languages, etags creates tags for function
279 declarations when given the --declarations option.
281 *** In C++, tags are created for "operator". The tags have the form
282 "operator+", without spaces between the keyword and the operator.
284 *** New language Ada: tags are functions, procedures, packages, tasks, and
287 *** In Fortran, procedure is no more tagged.
289 *** In Java, tags are created for "interface".
291 *** In Lisp, "(defstruct (foo", "(defun (operator" and similar constructs
294 *** In Perl, the --globals option tags global variables. my and local
295 variables are tagged.
297 *** New language Python: def and class at the beginning of a line are tags.
299 *** .ss files are Scheme files, .pdb is Postscript with C syntax, .psw is
303 * Lisp and internal changes in XEmacs 21.2
304 ==========================================
306 ** A new portable dumper is available for beta testing.
308 Olivier Galibert has written a portable dumper for XEmacs, based on
309 initial work by Kyle Jones. Normally, XEmacs C sources link into an
310 executable called `temacs', which loads the Lisp code and "unexecs"
311 into a proper `xemacs' executable. The unexec() process is hard to
312 implement correctly and makes XEmacs very hard to port to new
313 operating systems, or even to new releases of old systems.
315 A portable dumper is a different approach to dumping: instead of
316 dumping full-fledged executable, it only dumps out the initialized
317 data structures (both Lisp and C) into an external file. A normally
318 running XEmacs only needs to mmap() that file and relocate a bit to
319 get to the initialized data. In that scheme, there is no difference
320 between `temacs' and `xemacs'.
322 This is all very experimental, though. Configure with `--pdump' to
325 ** Much effort has been invested to make XEmacs Lisp faster:
327 *** Many basic lisp operations are now faster.
328 This is especially the case when running a Mule-enabled XEmacs.
330 A general overhaul of the lisp engine should produce a speedup of 1.4
331 in a Latin-1 XEmacs, and 2.1 in a Mule XEmacs. These numbers were
332 obtained running `(byte-compile "simple.el")', which should be a
333 pretty typical test of "pure" Lisp.
335 *** Lisp hash tables have been re-implemented. The Common Lisp style
336 hash table interface has been made standard, and moved from cl.el into
337 fast C code (See the section on hash tables in the XEmacs Lisp
338 Reference). A speedup factor of 3 can be expected with code that
339 makes intensive use of hash tables.
341 *** The garbage collector has been tuned, leading to a speedup of
344 *** The family of functions that iterate over lists, like `memq', and
345 `rassq', have been made a little faster (typically 1.3).
347 *** Lisp function calls are faster, by approximately a factor of two.
348 However, defining inline functions (via defsubst) still makes sense
351 *** Finally, a few functions have had dramatic performance
352 improvements. For example, `(last long-list)' is now 30 times faster.
354 Of course, your mileage will vary.
356 Many operations do not see any improvement. Surprisingly, running
357 (font-lock-fontify-buffer) does not use the Lisp engine much at all.
358 Speeding up your favorite slow operation is an excellent project to
359 improve XEmacs. Don't forget to profile!
361 ** Native widgets can be displayed in buffers.
363 The glyph system has been extended to allow the display of glyphs that
364 are implemented as native window-system widgets. Thus you can embed
365 buttons, scrollbars, combo boxes, edit fields and progress gauges in a
366 buffer. As a side effect subwindow support now works once again.
368 All of this is still fairly experimental and there is no
369 documentation. The current APIs might change in a future version of
370 XEmacs. Some widgets are only available under MS-Windows. See the
371 file glyphs-test.el in the XEmacs src distribution for examples of
374 The buffers-tab functionality and progress gauge have been implemented
377 ** `user-init-file' and `user-init-directory' are now absolute
378 file/directory names. Previously, both variables used to be relative
379 to (concat "~" init-file-user). This turned out to be too complicated
380 for most packages (and some core Lisp files) to use correctly. Also,
381 the `init-file-user' variable has been obsoleted in the process.
383 The user-visible options like `-u' have not changed their behavior.
385 ** XEmacs finally has an automated test suite!
386 Although this is not yet very sophisticated, it is already responsible
387 for several important bug fixes in XEmacs. To try it out, simply use
388 the makefile target `make check' after building XEmacs.
390 ** Hash tables have been reimplemented.
391 As was pointed out above, the standard interface to hash tables is now
392 the Common Lisp interface, as described in Common Lisp, the Language
393 (CLtL2, by Steele). The older interface (functions with names
394 containing the phrase `hashtable') will continue to work, but the
395 preferred interface now has names containing the phrase `hash-table'.
397 Here's the executive overview: create hash tables using
398 make-hash-table, and use gethash, puthash, remhash, maphash and
399 clrhash to manipulate entries in the hash table. See the (updated)
400 Lisp Reference Manual for details.
402 ** Lisp code handles circular lists much more robustly.
403 Many basic lisp functions used to loop forever when given a circular
404 list, expecting you to C-g (quit) out of the loop. Now this is more
405 likely to trigger a `circular-list' error. Printing a circular list
406 now results in something like this:
408 (let ((x (cons 'foo 'foo)))
411 => (foo ... <circular list>)
413 An extra bonus is that checking for circularities is not just
414 friendlier, but actually faster than checking for C-g.
416 ** Functions for decoding base64 encoding are now available; see
417 `base64-encode-region', `base64-encode-string', `base64-decode-region'
418 and `base64-decode-string'.
420 ** The functions `read-string', `read-expression', `eval-minibuffer',
421 `read-variable', `read-command', `read-function', `read-number',
422 `read-shell-command', `read-from-minibuffer', and `completing-read'
423 now take an additional argument which specifies the default value. If
424 this argument is non-nil, it should be a string; that string is used
427 It is returned if the user enters empty input.
428 It is available through the history command M-n.
432 *** The LDAP interface now consists of two layers, a low-level layer
433 that closely matches the LDAP C API, and a more convenient
434 higher-level set of functions.
436 *** The low-level functions that used to be named *-internal are now
437 named more simply: `ldap-open', `ldap-close', `ldap-search-basic',
438 `ldap-add', and `ldap-modify'. They should be used directly for very
439 specific purposes (such as multiple operations on a connection) only.
441 *** The higher-level functions provide a more convenient way to access
442 LDAP directories hiding the subtleties of handling the connection,
443 translating arguments and ensuring compliance with LDAP
444 internationalization rules and formats (currently partly implemented
445 only.) This layer provides atomic operations for searches,
446 modification, addition and deletion of multiple entries at once:
447 `ldap-search-entries', `ldap-add-entries', `ldap-delete-entries', and
448 `ldap-modify-entries'.
450 *** To maintain compatibility with previous code, the now obsolete
451 function `ldap-search' is now merely a wrapper that calls either
452 `ldap-search-basic' or `ldap-search-entries'. Please don't use the
453 `ldap-search' function in your new programs -- a direct call to one of
454 the two replacements is more efficient and unambiguous.
456 ** The arguments to `locate-file' are now more Lisp-like. As before,
459 (locate-file FILENAME PATH-LIST &optional SUFFIXES MODE)
461 Except that SUFFIXES are now a list of strings instead of a single,
462 colon-separated string. MODE is now a symbol or a list of symbols
463 (symbols `exists', `executable', `writable', and `readable' are
464 supported) instead of an integer code. See the documentation for
465 details. Of course, the old form is still accepted for backward
468 Several bugs in locate-file have been fixed, most notably its failure
469 to call expand-file-name on elements of PATH-LIST. Because of that
470 elements of load-path of the form "~/..." used to not work.
471 locate-file is now guaranteed to expand files during its course of
474 ** `translate-region' has been improved in several ways. Its TABLE
475 argument used to be a 256-character string. In addition to this, it
476 can now also be a vector or a char-table, which makes the function
477 useful for Mule, which it wasn't. If TABLE a vector or a generic
478 char-table, you can map characters to strings instead of to other
479 characters. For instance:
481 (let ((table (make-char-table 'generic)))
482 (put-char-table ?a "the letter a" table)
483 (put-char-table ?b "" table)
484 (put-char-table ?c ?\n table)
485 (translate-region (point-min) (point-max) table))
487 ** The new form `ignore-file-errors', similar to `ignore-errors' may
488 be used as a short-hand for condition-case when you wish to ignore
489 file-related error. For example:
491 (ignore-file-errors (delete-file "foo"))
493 ** The first argument to `intern-soft' may now also be a symbol, like
494 with `unintern'. If given a symbol, `intern-soft' will look for that
495 exact symbol rather than for any string. This is useful when you want
496 to check whether a specific symbol is interned in an obarray, e.g.:
501 (intern-soft (make-symbol "foo"))
504 ** The `keywordp' function now returns non-nil only on symbols
505 interned in the global obarray. For example:
507 (keywordp (intern ":foo" [0]))
509 (keywordp (intern ":foo")) ; The same as (keywordp :foo)
512 This behavior is compatible with other code which treats symbols
513 beginning with colon as keywords only if they are interned in the
514 global obarray. `keywordp' used to wrongly return t in both cases
517 ** New variables `this-command-properties' and
518 `last-command-properties' are now available for communication between
519 consecutive commands. Commands should use these to communicate with
520 the pre/post-command hooks, subsequent commands, wrapping commands,
521 etc. in preference to looking at and/or setting `this-command'.
523 ** New functions `add-one-shot-hook' and `add-local-one-shot-hook' make
524 it possible to add a "one-shot" hook, which is to say a hook that runs
525 only once, and automatically removes itself after the first time it
528 ** The descriptor that specifies the text of a menu item can now be an
529 evaluated expression. This makes this descriptor parallel with
530 others, which can also be expressions.
533 * Changes in XEmacs 21.0
534 ========================
536 ** XEmacs has been unbundled into constituent installable packages.
537 See the Info documentation under "Packages" for more information.
538 See the file `etc/PACKAGES' in the distribution for a partial list of
539 packages available at the time of the 21.0 release.
541 ** XEmacs is now supported under Microsoft Windows 95/98 and Windows
542 NT operating systems. For starters, look at the XEmacs on Windows FAQ
543 at <URL:http://jagor.srce.hr/~hniksic/xemacs-on-windows-faq.txt>. To
544 discuss Windows-specific issues, subscribe to the mailing list at
545 <xemacs-nt-request@xemacs.org>.
547 ** XEmacs will now use `XEmacs' as its application class if it finds
548 any `XEmacs' resources in the resource database. Otherwise, it will
549 continue to use the `Emacs' class.
551 ** The options menu has been ported to Custom.
552 This means that each entry in the options menu acts as if you had customized
553 the corresponding variable by hand. ### WARNING: there is currently no
554 upgrading function to help you port your old options settings to the new
555 format. Consequently, if you want to modify the options for XEmacs 21, you
556 will have to set them all again through the menu, and remove the code loading
557 .xemacs-options from your .emacs.
559 ** When the Zmacs region is active, `M-x query-replace' and the other
560 replace commands now operate on the region contents only.
562 ** XEmacs now is able to choose X visuals and use private colormaps.
563 The '-visual <visualStr>' command line option or the '.EmacsVisual'
564 Xresource controls which visual XEmacs will use, and
565 '-privateColormap' or '.privateColormap' will force XEmacs to create a
566 private colormap for use. The syntax for the visual string is
567 "<visual><bitdepth>" where <visual> is one of 'StaticColor',
568 'TrueColor', 'GrayScale', 'PseudoColor' or 'DirectColor' and
569 <bitdepth> is the appropriate number of bits per pixel. If an invalid
570 or non-supported combination is entered, XEmacs attempts to find a happy
571 medium. The X creation mechanism will then determine if it needs to
572 create a colormap for use, or the presence of the private flags will
573 force it to create it.
575 ** The `imenu' package has been ported to XEmacs and is available as a
578 ** `echo-keystrokes' can now be a floating-point number, so that you
579 can set it to intervals shorter than one second.
581 (setq echo-keystrokes 0.1)
583 ** The new command `center-to-window-line' works like `recenter'
584 (bound to `C-l'), only it does not redisplay the whole display area.
586 ** The M-. command will now first search through exact tags matches,
587 and then through inexact matches, as one would expect.
589 ** The new variable `user-full-name' can be used to customize one's
590 name when using the Emacs mail and news reading facilities.
592 Normally, `user-full-name' is a function that returns the full name of
593 a user or UID, as specified by the system -- for instance,
594 (user-full-name "root") returns something like "Super-User". However,
595 when the function is called without arguments, it will return the
596 value of the `user-full-name' variable. The `user-full-name' variable
597 is initialized using the environment variable NAME and (failing that)
598 the user's system name.
600 The behavior of the `user-full-name' function with an argument
601 specified is unchanged.
603 ** The new command `M-x customize-changed-options' lets you customize
604 all the options whose default values have changed in recent Emacs
605 versions. You specify a previous Emacs version number as argument,
606 and the command creates a customization buffer showing all the
607 customizable options whose default values were changed since that
610 If you don't specify a particular version number argument, then the
611 customization buffer shows all the customizable options for which
612 Emacs versions of changes are recorded.
614 ** The new command `add-log-convert' can be used to convert the
615 old-style (pre-20.3) ChangeLog buffers to new style, for
616 consistency. A reminder: if you wish to revert to old-style
617 ChangeLogs instead, customize the value of `add-log-time-format'
620 ** The new command `zap-up-to-char' is now available. It is similar
621 to `zap-to-char', except that it does not delete the searched-for
622 character. It is not bound to a key by default.
624 ** You can now store a number into a register with `C-u NUMBER C-x r n'
625 REG, increment it by INC with `C-u INC C-x r + REG' (to increment by
626 one, omit C-u INC), and insert it in the buffer with `C-x r g REG'.
627 This is useful for writing keyboard macros.
629 ** The M-: command, when given a prefix argument, will now insert its
630 result to the current buffer.
632 ** The `C-h c' command, when given a prefix argument, will now insert
633 the message into the current buffer.
635 ** Horizontally split windows may now be dragged using the mouse.
636 Because of this, the dividers between vertical windows are always
637 visible. To turn it off, set `vertical-divider-always-visible-p' to
640 ** XEmacs/Mule (internationalization) changes.
642 *** Mule support now works on TTY's. Use `set-terminal-coding-system'
643 and `set-keyboard-coding-system' to specify the coding system of your
644 display and keyboard.
646 *** Egg/SJ3 input method is now officially supported. Quail and
647 Egg/Skk have been available through the generalized Leim since 20.3.
649 *** Localized Japanese menubars are available if XEmacs is built with
650 XFONTSET and either the X11 libraries are built with X_LOCALE defined
651 or the native C libraries support Japanese localization. This has
652 been available since 20.3, only it hasn't been announced before.
654 ** Jamie Zawinski's `gdb-highlight' extension is now distributed with
655 the `debug' package. gdb-highlight makes most objects printed in a
656 gdb buffer be mouse-sensitive: as text shows up in the buffer, it is
657 parsed, and objects which are recognized have context-sensitive
658 commands attached to them. To use it, add the following to `.emacs':
660 (add-hook 'gdb-mode-hook (lambda () (require 'gdb-highlight)))
662 ** The package popper.el is now included in the edit-utils package.
663 It has been greatly enhanced with respect to the one once included
664 with the ilisp package and should work well under XEmacs 21.0.
668 *** Like the old 'gnudoit' program. Gnuclient -batch now can read from stdin.
670 *** Gnuclient -batch no longer breaks off the output at the first LF.
674 *** Multiline macros are now handled, both as they affect indentation,
675 and as recognized syntax. New syntactic symbol cpp-macro-cont is
676 assigned to second and subsequent lines of a multiline macro
679 *** A new style "user" which captures all non-hook-ified
680 (i.e. top-level) .emacs file variable setings and customizations.
681 Style "cc-mode" is an alias for "user" and is deprecated. "gnu" style
682 is still the default however.
684 *** "java" style now conforms to Sun's JDK coding style.
686 *** There are new commands c-beginning-of-defun, c-end-of-defun which
687 are alternatives which you could bind to C-M-a and C-M-e if you prefer
688 them. They do not have key bindings by default.
690 *** New and improved implementations of M-a (c-beginning-of-statement)
691 and M-e (c-end-of-statement).
693 *** C++ namespace blocks are supported, with new syntactic symbols
694 namespace-open, namespace-close, and innamespace.
696 *** File local variable settings of c-file-style and c-file-offsets
697 makes the style variables local to that buffer only.
699 *** New indentation functions c-lineup-close-paren,
700 c-indent-one-line-block, c-lineup-dont-change.
702 *** Improvements (hopefully!) to the way CC Mode is loaded. You
703 should now be able to do a (require 'cc-mode) to get the entire
704 package loaded properly for customization in your .emacs file. A new
705 variable c-initialize-on-load controls this and is t by default.
707 ** In Text mode, now only blank lines separate paragraphs.
708 This makes it possible to get the full benefit of Adaptive Fill mode
709 in Text mode, and other modes derived from it (such as Mail mode).
710 TAB in Text mode now runs the command indent-relative; this makes a
711 practical difference only when you use indented paragraphs.
713 As a result, the old Indented Text mode is now identical to Text mode,
714 and is an alias for it.
716 If you want spaces at the beginning of a line to start a paragraph,
717 use the new mode, Paragraph Indent Text mode.
719 ** Changes to Gnus, the XEmacs newsreader.
721 *** New functionality for using Gnus as an offline newsreader has been
722 added. A plethora of new commands and modes have been added. See the
723 Gnus manual for the full story.
725 *** The nndraft backend has returned, but works differently than
726 before. All Message buffers are now also articles in the nndraft
727 group, which is created automatically.
729 *** `gnus-alter-header-function' can now be used to alter header
732 *** `gnus-summary-goto-article' now accept Message-ID's.
734 *** A new Message command for deleting text in the body of a message
735 outside the region: `C-c C-v'.
737 *** You can now post to component group in nnvirtual groups with
740 *** `nntp-rlogin-program' -- new variable to ease customization.
742 *** `C-u C-c C-c' in `gnus-article-edit-mode' will now inhibit
743 re-highlighting of the article buffer.
745 *** New element in `gnus-boring-article-headers' -- `long-to'.
747 *** `M-i' symbolic prefix command. See the section "Symbolic
748 Prefixes" in the Gnus manual for details.
750 *** `L' and `I' in the summary buffer now take the symbolic prefix
751 `a' to add the score rule to the "all.SCORE" file.
753 *** `gnus-simplify-subject-functions' variable to allow greater
754 control over simplification.
756 *** `A T' -- new command for fetching the current thread.
758 *** `/ T' -- new command for including the current thread in the
761 *** `M-RET' is a new Message command for breaking cited text.
763 *** \\1-expressions are now valid in `nnmail-split-methods'.
765 *** The `custom-face-lookup' function has been removed.
766 If you used this function in your initialization files, you must
767 rewrite them to use `face-spec-set' instead.
769 *** Cancelling now uses the current select method. Symbolic prefix
770 `a' forces normal posting method.
772 *** New command to translate M******** sm*rtq**t*s into proper text
775 *** For easier debugging of nntp, you can set `nntp-record-commands'
778 *** nntp now uses ~/.authinfo, a .netrc-like file, for controlling
779 where and how to send AUTHINFO to NNTP servers.
781 *** A command for editing group parameters from the summary buffer
784 *** A history of where mails have been split is available.
786 *** A new article date command has been added -- `article-date-iso8601'.
788 *** Subjects can be simplified when threading by setting
789 `gnus-score-thread-simplify'.
791 *** A new function for citing in Message has been added --
792 `message-cite-original-without-signature'.
794 *** `article-strip-all-blank-lines' -- new article command.
796 *** A new Message command to kill to the end of the article has
799 *** A minimum adaptive score can be specified by using the
800 `gnus-adaptive-word-minimum' variable.
802 *** The "lapsed date" article header can be kept continually
803 updated by the `gnus-start-date-timer' command.
805 *** Web listserv archives can be read with the nnlistserv backend.
807 *** Old dejanews archives can now be read by nnweb.
809 *** Byte-compilation of user-specs now works under XEmacs.
811 ** The `dir' files are no longer essential for functioning of the Info
812 subsystem. If the `dir' file does not exist in an Info directory, the
813 relevant information will be generated on-the-fly.
815 This behavior can be customized, look for `Info-auto-generate-directory'
816 and `Info-save-auto-generated-dir' in the `info' customization group.
819 * Lisp and internal changes in XEmacs 21.0
820 ==========================================
822 ** It is now possible to build XEmacs with support for 31-bit Lisp
823 integers (normally, Lisp integers are only 28 bits wide on 32-bit
824 machines.) Configure with --use-minimal-tagbits to test. With this
825 change, the maximum buffer size on 32-bit machines is increased from
826 128M to 1G. This setting will be made default in a future XEmacs
829 ** Specifier changes.
831 *** When instantiating a specifier, the window locale now has a higher
832 precedence than the buffer locale. This is because the window locale
833 is more specific than the buffer locale.
835 *** The new macro `let-specifier' can be used to temporarily add
836 specifications to specifiers. See the documentation for details.
838 *** The new specifiers `vertical-scrollbar-visible-p' and
839 `horizontal-scrollbar-visible-p' may be used to control scrollbar
840 visibility. Previously, the only way to remove a scrollbar was to set
841 its size to 0. This method is still supported for backward
844 *** The new specifiers `scrollbar-on-left-p' and `scrollbar-on-top-p'
845 may be used to control the position of the vertical and horizontal
846 toolbar. Previously, their position could be changed only through the
849 *** The new draggable vertical dividers between windows may be turned
850 off using the `vertical-divider-always-visible-p' specifier. When
851 this is set to nil, the vertical dividers between windows are shown
852 only when needed, and they are not draggable.
854 Other properties of the vertical dividers may be controlled using
855 `vertical-divider-shadow-thickness', `vertical-divider-line-width' and
856 `vertical-divider-spacing' specifiers, which see.
858 ** Frame focus management changes.
860 *** When the variable focus-follows-mouse is non-nil, `select-frame'
861 no longer permanently selects a different frame. The frame selection
862 is temporary and is reverted when the current command terminates, much
863 like the buffer selected by `set-buffer'. This is the same as in FSF
866 *** The new function `focus-frame' sets the window system focus to
867 FRAME (and selects it), regardless of the value of
868 `focus-follows-mouse'. Doing this is not well behaved, so be
869 absolutely sure that you want this.
871 The code that uses `select-frame' only to get the window manager focus
872 should be changed to use `set-frame-focus' instead, so that they keep
873 working when `focus-follows-mouse' is non-nil.
875 *** The special forms `save-selected-frame' and `with-selected-frame'
876 can now be used to temporarily change selected frame.
878 *** The behavior of `other-frame' command (`C-x 5 o') is unaffected by
881 ** The function `select-window' now has an optional second argument
882 NORECORD which if non-nil inhibits the recording of a buffer change.
884 ** The function `vertical-motion' now correctly handles the second,
885 optional WINDOW argument. A new third argument PIXELS, if non-nil,
886 indicates that the returned motion should be in pixels.
888 ** The new function `vertical-motion-pixels' is similar to
889 vertical-motion but takes as input a vertical motion in pixels.
891 ** The new functions window-text-area-pixel-{width,height,edges} can
892 be used to obtain information about the text-displaying area of a
895 ** The new functions `shrink-window-pixels' and `enlarge-window-pixels'
896 can be used to adjust the size of a window by a pixel amount.
898 ** The new function `window-displayed-text-pixel-height' can be used
899 to determine the height of the text actually displayed in a window.
901 ** The arithmetic comparison functions <, >, =, /= now accept a
902 variable number of arguments.
904 This means that if you want to test whether A < B < C, you can write
905 it as (< A B C) instead of (and (< A B) (< B C)). Likewise,
906 (apply #'> LIST) now tests if LIST is monotonously increasing -- and
909 ** The XEmacs hashtables now have a consistent read/print syntax.
910 This means that a hashtable will be readably printed in a
913 #s(hashtable size 2 data (key1 value1 key2 value2))
915 When XEmacs reads this form, it will create a new hashtable according
916 to description. This allows you to easily dump hashtables to files
917 using `prin1', and read them back in using `read'.
919 If `print-readably' is non-nil, a more relaxed syntax is used; for
922 #<hashtable size 2/13 data (key1 value1 key2 value2) 0x874d>
924 ** It is now possible to build XEmacs with LDAP support.
925 You will need to install a LDAP library first. The following have
927 - LDAP 3.3 from the University of Michigan
928 (get it from <URL:http://www.umich.edu/~dirsvcs/ldap/>)
929 - OpenLDAP 1.0.3 from the OpenLDAP Foundation
930 (get it from <URL:http://www.openldap.org/>)
931 - LDAP SDK 1.0 from Netscape Corp.
932 (get it from <URL:http://developer.netscape.com/>)
934 ** When profiling is in effect, a call-count of all recorded functions
935 is now calculated. This information is stored in
936 `call-count-profile-table', and is utilized by `profile-results' as
937 well as the new command `profile-call-count-results'.
939 ** It is now an error to change the value of a symbol whose name
940 starts with a colon, if it is interned in the standard obarray.
942 However, setting such a symbol to its proper value, which is that
943 symbol itself, is not an error. This is for the sake of programs that
944 support pre-19.12 XEmacs and pre-20 GNU Emacs by explicitly setting
945 these variables to themselves.
947 ** The `concat' function no longer accepts integer arguments.
949 ** The new function `string' concatenates all its argument characters
950 and returns the resulting string. This is consistent with other
951 functions, like `list', `vector', etc.
953 ** The function `temp-directory' is now available to return the
954 directory to store temporary files. On Unix this will be obtained
955 from TMPDIR, defaulting to `/tmp'.
957 ** The function load-average now accepts an optional argument
958 USE-FLOATS. If it is non-nil, the load average values are returned as
959 floating point numbers, rather than as integers to be divided by 100.
961 ** The `make-event' function now supports the TYPE and PLIST
962 arguments, which can be used to create various events from Lisp. See
963 the documentation for details.
965 ** `function-interactive' is a new function that returns the
966 interactive specification of a funcallable object.
968 ** The new `lmessage' function allows printing of a formatted message
969 with a particular label.
971 (lmessage 'progress "Processing... %d" counter)
973 This function is more convenient than `display-message' because it
974 automatically applies `format' to its arguments.
976 ** The new `lwarn' function, analogous to `lmessage', allows printing
977 a formatted warning, with a non-default CLASS or LABEL.
979 ** The new function `split-path' can now be used to explode the
980 components of a colon-separated search path into a list.
982 (split-path "foo:bar")
985 ** Specifiers and symbols whose value is a specifier are now allowed
986 as modeline specifications.
988 ** defcustom now accepts the keyword `:version'. Use this to specify
989 in which version of Emacs a certain variable's default value changed.
992 (defcustom foo-max 34 "*Maximum number of foo's allowed."
997 This information is used to control the customize-changed-options
1000 ** The line number tracking in modeline is now efficient, even for
1001 very large buffers. This is achieved by caching the line numbers of
1002 recent buffer positions, and reusing them. This cache is used only in
1003 the buffers where `line-number-mode' is in effect.
1005 ** When the new GNU Malloc aka Doug Lea Malloc is available, it will
1006 be used. This should result in better performance on Linux systems
1009 ** The code XEmacs uses to assemble its various paths into the
1010 directory hierarchy has been rewritten to support the package system.
1011 Look under "Startup Paths" in the Info documentation for more
1014 *** site-lisp is no longer part of the load-path by default.
1015 Its use is deprecated, but you can specify --with-site-lisp=yes at the
1016 configure command line to get it back.
1018 *** `Info-default-directory-list' is now obsolete. If you want to
1019 change the path which XEmacs uses to search for info files, set
1020 `Info-directory-list' instead.