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 ** You can now create "indirect buffers", like in GNU Emacs. An
37 indirect buffer shares its text with another buffer ("base buffer"),
38 but has its own major mode, local variables, extents, and narrowing.
39 An indirect buffer has a name of its own, distinct from those of the
40 base buffer and all other buffers. An indirect buffer cannot itself
41 be visiting a file (though its base buffer can be). The base buffer
42 cannot itself be indirect.
44 Use (make-indirect-buffer BASE-BUFFER NAME) to make an indirect buffer
45 named NAME whose base is BASE-BUFFER. If BASE-BUFFER is an indirect
46 buffer, its base buffer is used as the base for the new buffer.
48 You can make an indirect buffer current, or switch to it in a window,
49 just as you would a non-indirect buffer.
51 The function `buffer-base-buffer', given an indirect buffer, returns
52 its base buffer. It returns nil when given an ordinary buffer (not
53 indirect). `buffer-indirect-children' returns a list of the indirect
54 children of a base buffer.
57 * Lisp and internal changes in XEmacs 21.0
58 ==========================================
60 ** Functions for decoding base64 encoding are now available; see
61 `base64-encode-region', `base64-encode-string', `base64-decode-region'
62 and `base64-decode-string'.
65 * Changes in XEmacs 21.0
66 ========================
68 ** XEmacs has been unbundled into constituent installable packages.
69 See the Info documentation under "Packages" for more information.
70 See the file `etc/PACKAGES' in the distribution for a partial list of
71 packages available at the time of the 21.0 release.
73 ** XEmacs is now supported under Microsoft Windows 95/98 and Windows
74 NT operating systems. For starters, look at the XEmacs on Windows FAQ
75 at <URL:http://jagor.srce.hr/~hniksic/xemacs-on-windows-faq.txt>. To
76 discuss Windows-specific issues, subscribe to the mailing list at
77 <xemacs-nt-request@xemacs.org>.
79 ** XEmacs will now use `XEmacs' as its application class if it finds
80 any `XEmacs' resources in the resource database. Otherwise, it will
81 continue to use the `Emacs' class.
83 ** The options menu has been ported to Custom.
84 This means that each entry in the options menu acts as if you had customized
85 the corresponding variable by hand. ### WARNING: there is currently no
86 upgrading function to help you port your old options settings to the new
87 format. Consequently, if you want to modify the options for XEmacs 21, you
88 will have to set them all again through the menu, and remove the code loading
89 .xemacs-options from your .emacs.
91 ** When the Zmacs region is active, `M-x query-replace' and the other
92 replace commands now operate on the region contents only.
94 ** Using the new `-private' option, you can make XEmacs use a private
97 ** The `imenu' package has been ported to XEmacs and is available as a
100 ** `echo-keystrokes' can now be a floating-point number, so that you
101 can set it to intervals shorter than one second.
103 (setq echo-keystrokes 0.1)
105 ** The new command `center-to-window-line' works like `recenter'
106 (bound to `C-l'), only it does not redisplay the whole display area.
108 ** The M-. command will now first search through exact tags matches,
109 and then through inexact matches, as one would expect.
111 ** The new variable `user-full-name' can be used to customize one's
112 name when using the Emacs mail and news reading facilities.
114 Normally, `user-full-name' is a function that returns the full name of
115 a user or UID, as specified by the system -- for instance,
116 (user-full-name "root") returns something like "Super-User". However,
117 when the function is called without arguments, it will return the
118 value of the `user-full-name' variable. The `user-full-name' variable
119 is initialized using the environment variable NAME and (failing that)
120 the user's system name.
122 The behaviour of the `user-full-name' function with an argument
123 specified is unchanged.
125 ** The new command `M-x customize-changed-options' lets you customize
126 all the options whose default values have changed in recent Emacs
127 versions. You specify a previous Emacs version number as argument,
128 and the command creates a customization buffer showing all the
129 customizable options whose default values were changed since that
132 If you don't specify a particular version number argument, then the
133 customization buffer shows all the customizable options for which
134 Emacs versions of changes are recorded.
136 ** The new command `add-log-convert' can be used to convert the
137 old-style (pre-20.3) ChangeLog buffers to new style, for
138 consistency. A reminder: if you wish to revert to old-style
139 ChangeLogs instead, customize the value of `add-log-time-format'
142 ** The new command `zap-up-to-char' is now available. It is similar
143 to `zap-to-char', except that it does not delete the searched-for
144 character. It is not bound to a key by default.
146 ** You can now store a number into a register with `C-u NUMBER C-x r n'
147 REG, increment it by INC with `C-u INC C-x r + REG' (to increment by
148 one, omit C-u INC), and insert it in the buffer with `C-x r g REG'.
149 This is useful for writing keyboard macros.
151 ** The M-: command, when given a prefix argument, will now insert its
152 result to the current buffer.
154 ** The `C-h c' command, when given a prefix argument, will now insert
155 the message into the current buffer.
157 ** Horizontally split windows may now be dragged using the mouse.
158 Because of this, the dividers between vertical windows are always
159 visible. To turn it off, set `vertical-divider-always-visible-p' to
162 ** XEmacs/Mule (internationalization) changes.
164 *** Mule support now works on TTY's. Use `set-terminal-coding-system'
165 and `set-keyboard-coding-system' to specify the coding system of your
166 display and keyboard.
168 *** Egg/SJ3 input method is now officially supported. Quail and
169 Egg/Skk have been available through the generalized Leim since 20.3.
171 *** Localized Japanese menubars are available if XEmacs is built with
172 XFONTSET and either the X11 libraries are built with X_LOCALE defined
173 or the native C libraries support Japanese localization. This has
174 been available since 20.3, only it hasn't been announced before.
176 ** Jamie Zawinski's `gdb-highlight' extension is now distributed with
177 the `debug' package. gdb-highlight makes most objects printed in a
178 gdb buffer be mouse-sensitive: as text shows up in the buffer, it is
179 parsed, and objects which are recognized have context-sensitive
180 commands attached to them. To use it, add the following to `.emacs':
182 (add-hook 'gdb-mode-hook (lambda () (require 'gdb-highlight)))
184 ** The package popper.el is now included in the edit-utils package.
185 It has been greatly enhanced with respect to the one once included
186 with the ilisp package and should work well under XEmacs 21.0.
190 *** Multiline macros are now handled, both as they affect indentation,
191 and as recognized syntax. New syntactic symbol cpp-macro-cont is
192 assigned to second and subsequent lines of a multiline macro
195 *** A new style "user" which captures all non-hook-ified
196 (i.e. top-level) .emacs file variable setings and customizations.
197 Style "cc-mode" is an alias for "user" and is deprecated. "gnu" style
198 is still the default however.
200 *** "java" style now conforms to Sun's JDK coding style.
202 *** There are new commands c-beginning-of-defun, c-end-of-defun which
203 are alternatives which you could bind to C-M-a and C-M-e if you prefer
204 them. They do not have key bindings by default.
206 *** New and improved implementations of M-a (c-beginning-of-statement)
207 and M-e (c-end-of-statement).
209 *** C++ namespace blocks are supported, with new syntactic symbols
210 namespace-open, namespace-close, and innamespace.
212 *** File local variable settings of c-file-style and c-file-offsets
213 makes the style variables local to that buffer only.
215 *** New indentation functions c-lineup-close-paren,
216 c-indent-one-line-block, c-lineup-dont-change.
218 *** Improvements (hopefully!) to the way CC Mode is loaded. You
219 should now be able to do a (require 'cc-mode) to get the entire
220 package loaded properly for customization in your .emacs file. A new
221 variable c-initialize-on-load controls this and is t by default.
223 ** In Text mode, now only blank lines separate paragraphs.
224 This makes it possible to get the full benefit of Adaptive Fill mode
225 in Text mode, and other modes derived from it (such as Mail mode).
226 TAB in Text mode now runs the command indent-relative; this makes a
227 practical difference only when you use indented paragraphs.
229 As a result, the old Indented Text mode is now identical to Text mode,
230 and is an alias for it.
232 If you want spaces at the beginning of a line to start a paragraph,
233 use the new mode, Paragraph Indent Text mode.
235 ** Changes to Gnus, the XEmacs newsreader.
237 *** New functionality for using Gnus as an offline newsreader has been
238 added. A plethora of new commands and modes have been added. See the
239 Gnus manual for the full story.
241 *** The nndraft backend has returned, but works differently than
242 before. All Message buffers are now also articles in the nndraft
243 group, which is created automatically.
245 *** `gnus-alter-header-function' can now be used to alter header
248 *** `gnus-summary-goto-article' now accept Message-ID's.
250 *** A new Message command for deleting text in the body of a message
251 outside the region: `C-c C-v'.
253 *** You can now post to component group in nnvirtual groups with
256 *** `nntp-rlogin-program' -- new variable to ease customization.
258 *** `C-u C-c C-c' in `gnus-article-edit-mode' will now inhibit
259 re-highlighting of the article buffer.
261 *** New element in `gnus-boring-article-headers' -- `long-to'.
263 *** `M-i' symbolic prefix command. See the section "Symbolic
264 Prefixes" in the Gnus manual for details.
266 *** `L' and `I' in the summary buffer now take the symbolic prefix
267 `a' to add the score rule to the "all.SCORE" file.
269 *** `gnus-simplify-subject-functions' variable to allow greater
270 control over simplification.
272 *** `A T' -- new command for fetching the current thread.
274 *** `/ T' -- new command for including the current thread in the
277 *** `M-RET' is a new Message command for breaking cited text.
279 *** \\1-expressions are now valid in `nnmail-split-methods'.
281 *** The `custom-face-lookup' function has been removed.
282 If you used this function in your initialization files, you must
283 rewrite them to use `face-spec-set' instead.
285 *** Cancelling now uses the current select method. Symbolic prefix
286 `a' forces normal posting method.
288 *** New command to translate M******** sm*rtq**t*s into proper text
291 *** For easier debugging of nntp, you can set `nntp-record-commands'
294 *** nntp now uses ~/.authinfo, a .netrc-like file, for controlling
295 where and how to send AUTHINFO to NNTP servers.
297 *** A command for editing group parameters from the summary buffer
300 *** A history of where mails have been split is available.
302 *** A new article date command has been added -- `article-date-iso8601'.
304 *** Subjects can be simplified when threading by setting
305 `gnus-score-thread-simplify'.
307 *** A new function for citing in Message has been added --
308 `message-cite-original-without-signature'.
310 *** `article-strip-all-blank-lines' -- new article command.
312 *** A new Message command to kill to the end of the article has
315 *** A minimum adaptive score can be specified by using the
316 `gnus-adaptive-word-minimum' variable.
318 *** The "lapsed date" article header can be kept continually
319 updated by the `gnus-start-date-timer' command.
321 *** Web listserv archives can be read with the nnlistserv backend.
323 *** Old dejanews archives can now be read by nnweb.
325 *** Byte-compilation of user-specs now works under XEmacs.
327 ** The `dir' files are no longer essential for functioning of the Info
328 subsystem. If the `dir' file does not exist in an Info directory, the
329 relevant information will be generated on-the-fly.
331 This behaviour can be customized, look for `Info-auto-generate-directory'
332 and `Info-save-auto-generated-dir' in the `info' customization group.
335 * Lisp and internal changes in XEmacs 21.0
336 ==========================================
338 ** It is now possible to build XEmacs with support for 31-bit Lisp
339 integers (normally, Lisp integers are only 28 bits wide on 32-bit
340 machines.) Configure with --use-minimal-tagbits to test. With this
341 change, the maximum buffer size on 32-bit machines is increased from
342 128M to 1G. This setting will be made default in a future XEmacs
345 ** Specifier changes.
347 *** When instantiating a specifier, the window locale now has a higher
348 precedence than the buffer locale. This is because the window locale
349 is more specific than the buffer locale.
351 *** The new macro `let-specifier' can be used to temporarily add
352 specifications to specifiers. See the documentation for details.
354 *** The new specifiers `vertical-scrollbar-visible-p' and
355 `horizontal-scrollbar-visible-p' may be used to control scrollbar
356 visibility. Previously, the only way to remove a scrollbar was to set
357 its size to 0. This method is still supported for backward
360 *** The new specifiers `scrollbar-on-left-p' and `scrollbar-on-top-p'
361 may be used to control the position of the vertical and horizontal
362 toolbar. Previously, their position could be changed only through the
365 *** The new draggable vertical dividers between windows may be turned
366 off using the `vertical-divider-always-visible-p' specifier. When
367 this is set to nil, the vertical dividers between windows are shown
368 only when needed, and they are not draggable.
370 Other properties of the vertical dividers may be controlled using
371 `vertical-divider-shadow-thickness', `vertical-divider-line-width' and
372 `vertical-divider-spacing' specifiers, which see.
374 ** Frame focus management changes.
376 *** When the variable focus-follows-mouse is non-nil, `select-frame'
377 no longer permanently selects a different frame. The frame selection
378 is temporary and is reverted when the current command terminates, much
379 like the buffer selected by `set-buffer'. This is the same as in FSF
382 *** The new function `focus-frame' sets the window system focus to
383 FRAME (and selects it), regardless of the value of
384 `focus-follows-mouse'. Doing this is not well behaved, so be
385 absolutely sure that you want this.
387 The code that uses `select-frame' only to get the window manager focus
388 should be changed to use `set-frame-focus' instead, so that they keep
389 working when `focus-follows-mouse' is non-nil.
391 *** The special forms `save-selected-frame' and `with-selected-frame'
392 can now be used to temporarily change selected frame.
394 *** The behavior of `other-frame' command (`C-x 5 o') is unaffected by
397 ** The function `select-window' now has an optional second argument
398 NORECORD which if non-nil inhibits the recording of a buffer change.
400 ** The function `vertical-motion' now correctly handles the second,
401 optional WINDOW argument. A new third argument PIXELS, if non-nil,
402 indicates that the returned motion should be in pixels.
404 ** The new function `vertical-motion-pixels' is similar to
405 vertical-motion but takes as input a vertical motion in pixels.
407 ** The new functions window-text-area-pixel-{width,height,edges} can
408 be used to obtain information about the text-displaying area of a
411 ** The new functions `shrink-window-pixels' and `enlarge-window-pixels'
412 can be used to adjust the size of a window by a pixel amount.
414 ** The new function `window-displayed-text-pixel-height' can be used
415 to determine the height of the text actually displayed in a window.
417 ** The arithmetic comparison functions <, >, =, /= now accept a
418 variable number of arguments.
420 This means that if you want to test whether A < B < C, you can write
421 it as (< A B C) instead of (and (< A B) (< B C)). Likewise,
422 (apply #'> LIST) now tests if LIST is monotonously increasing -- and
425 ** The XEmacs hashtables now have a consistent read/print syntax.
426 This means that a hashtable will be readably printed in a
429 #s(hashtable size 2 data (key1 value1 key2 value2))
431 When XEmacs reads this form, it will create a new hashtable according
432 to description. This allows you to easily dump hashtables to files
433 using `prin1', and read them back in using `read'.
435 If `print-readably' is non-nil, a more relaxed syntax is used; for
438 #<hashtable size 2/13 data (key1 value1 key2 value2) 0x874d>
440 ** It is now possible to build XEmacs with LDAP support.
441 You will need to install a LDAP library first. The following have
443 - LDAP 3.3 from the University of Michigan
444 (get it from <URL:http://www.umich.edu/~dirsvcs/ldap/>)
445 - LDAP SDK 1.0 from Netscape Corp.
446 (get it from <URL:http://developer.netscape.com/>)
448 ** When profiling is in effect, a call-count of all recorded functions
449 is now calculated. This information is stored in
450 `call-count-profile-table', and is utilized by `profile-results' as
451 well as the new command `profile-call-count-results'.
453 ** It is now an error to change the value of a symbol whose name
454 starts with a colon, if it is interned in the standard obarray.
456 However, setting such a symbol to its proper value, which is that
457 symbol itself, is not an error. This is for the sake of programs that
458 support pre-19.12 XEmacs and pre-20 GNU Emacs by explicitly setting
459 these variables to themselves.
461 ** The `concat' function no longer accepts integer arguments.
463 ** The new function `string' concatenates all its argument characters
464 and returns the resulting string. This is consistent with other
465 functions, like `list', `vector', etc.
467 ** The function `temp-directory' is now available to return the
468 directory to store temporary files. On Unix this will be obtained
469 from TMPDIR, defaulting to `/tmp'.
471 ** The function load-average now accepts an optional argument
472 USE-FLOATS. If it is non-nil, the load average values are returned as
473 floating point numbers, rather than as integers to be divided by 100.
475 ** The `make-event' function now supports the TYPE and PLIST
476 arguments, which can be used to create various events from Lisp. See
477 the documentation for details.
479 ** `function-interactive' is a new function that returns the
480 interactive specification of a funcallable object.
482 ** The new `lmessage' function allows printing of a formatted message
483 with a particular label.
485 (lmessage 'progress "Processing... %d" counter)
487 This function is more convenient than `display-message' because it
488 automatically applies `format' to its arguments.
490 ** The new `lwarn' function, analogous to `lmessage', allows printing
491 a formatted warning, with a non-default CLASS or LABEL.
493 ** The new function `split-path' can now be used to explode the
494 components of a colon-separated search path into a list.
496 (split-path "foo:bar")
499 ** Specifiers and symbols whose value is a specifier are now allowed
500 as modeline specifications.
502 ** defcustom now accepts the keyword `:version'. Use this to specify
503 in which version of Emacs a certain variable's default value changed.
506 (defcustom foo-max 34 "*Maximum number of foo's allowed."
511 This information is used to control the customize-changed-options
514 ** The line number tracking in modeline is now efficient, even for
515 very large buffers. This is achieved by caching the line numbers of
516 recent buffer positions, and reusing them. This cache is used only in
517 the buffers where `line-number-mode' is in effect.
519 ** When the new GNU Malloc aka Doug Lea Malloc is available, it will
520 be used. This should result in better performance on Linux systems
523 ** The code XEmacs uses to assemble its various paths into the
524 directory hierarchy has been rewritten to support the package system.
525 Look under "Startup Paths" in the Info documentation for more
528 *** site-lisp is now longer part of the load-path by default.
529 Its use is deprecated, but you can specify --with-site-lisp=yes at the
530 configure command line to get it back.
532 *** `Info-default-directory-list' is now obsolete. If you want to
533 change the path which XEmacs uses to search for info files, set
534 `Info-directory-list' instead.