NEWS

GNU Emacs NEWS -- history of user-visible changes.

Copyright (C) 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
See the end of the file for license conditions.

Please send Emacs bug reports to bug-gnu-emacs@gnu.org.
If possible, use M-x report-emacs-bug.

This file is about changes in Emacs version 23.

See files NEWS.22, NEWS.21, NEWS.20, NEWS.19, NEWS.18, and NEWS.1-17
for changes in older Emacs versions.

You can narrow news to a specific version by calling `view-emacs-news'
with a prefix argument or by typing C-u C-h C-n.


* Installation Changes in Emacs 23.3

* Startup Changes in Emacs 23.3

* Changes in Emacs 23.3

** The nextstep port can have different modifiers for the left and right
alt/option key by customizing the value for ns-right-alternate-modifier.


* Editing Changes in Emacs 23.3


* Changes in Specialized Modes and Packages in Emacs 23.3

---
** The appt-add command takes an optional argument for the warning time.
This can be used in place of the default appt-message-warning-time.

** Obsolete packages

+++
*** lmenu.el and cl-compat.el are now obsolete.


* New Modes and Packages in Emacs 23.3


* Incompatible Lisp Changes in Emacs 23.3


* Lisp changes in Emacs 23.3

** `e' and `pi' are now called `float-e' and `float-pi'.
  The old names are obsolete.
** The use of unintern without an obarray arg is declared obsolete.

** New function byte-to-string, like char-to-string but for bytes.


* Changes in Emacs 23.3 on non-free operating systems


* Installation Changes in Emacs 23.2

** New configure options for Emacs developers.
These are not new features; only the configure flags are new.

*** --enable-profiling builds Emacs with profiling enabled.
This might not work on all platforms.

*** --enable-checking[=OPTIONS] builds emacs with extra runtime checks.

** `make install' now consistently ignores umask, creating a
world-readable install.

** Emacs compiles with Gconf support, if it is detected.
Use the configure option --without-gconf to disable this.
This is used by the `font-use-system-font' feature (see below).

* Startup Changes in Emacs 23.2

** The command-line option -Q (--quick) also inhibits loading X resources.
However, if Emacs is compiled with the Lucid or Motif toolkit, X
resource settings for the graphical widgets are still applied.
On Windows, the -Q option causes Emacs to ignore Registry settings,
but environment variables set on the Registry are still honored.

*** The new variable `inhibit-x-resources' shows whether X resources
were loaded.

** New command-line option -mm (--maximized) maximizes the initial frame.

* Changes in Emacs 23.2

** The maximum size of buffers (and the largest fixnum) is doubled.
On typical 32bit systems, buffers can now be up to 512MB.

** The default value of `trash-directory' is now nil.
This means that `move-file-to-trash' trashes files according to
freedesktop.org specifications, the same method used by the Gnome,
KDE, and XFCE desktops.  (This change has no effect on Windows, which
uses `system-move-file-to-trash' for trashing.)

** The pointer now becomes invisible when typing.
Customize `make-pointer-invisible' to disable this feature.

** Font changes

*** Emacs can use the system default monospaced font in Gnome.
To enable this feature, set `font-use-system-font' to non-nil (it is
nil by default).  If the system default changes, Emacs changes also.
This feature requires Gconf support, which is automatically included
at compile-time if configure detects the gconf libraries (you can
disable this with the configure option --without-gconf).

*** On X11, Emacs reacts to Xft changes made by configuration tools,
via the XSETTINGS mechanism.  This includes antialias, hinting,
hintstyle, RGBA, DPI and lcdfilter changes.

** Killing a buffer with a running process now asks for confirmation.
To remove this query, remove `process-kill-buffer-query-function' from
`kill-buffer-query-functions', or set the appropriate process flag
with `set-process-query-on-exit-flag'.

** File-local variable changes

*** Specifying a minor mode as a local variables enables that mode,
unconditionally.  The previous behavior, toggling the mode, was
neither reliable nor generally desirable.

*** There are new commands for adding and removing file-local variables:
`add-file-local-variable', `delete-file-local-variable',
`add-file-local-variable-prop-line', and
`delete-file-local-variable-prop-line'.

*** There are new commands for adding and removing directory-local variables,
and copying them to and from file-local variable lists:
`add-dir-local-variable', `delete-dir-local-variable',
`copy-dir-locals-to-file-locals',
`copy-dir-locals-to-file-locals-prop-line' and
`copy-file-locals-to-dir-locals'.

** Internationalization changes

*** Unibyte sessions are now considered obsolete.
This refers to the EMACS_UNIBYTE environment variable as well as the
--unibyte, --multibyte, --no-multibyte, and --no-unibyte command line
arguments.  Customizing enable-multibyte-characters and setting
default-enable-multibyte-characters are also deprecated.

*** New coding system `utf-8-hfs'.
This is suitable for default-file-name-coding-system on Mac OS X; see
international/ucs-normalize.el.

** Function arguments in *Help* buffers are now shown in upper-case.
Customize `help-downcase-arguments' to t to show them in lower-case.

** New command `async-shell-command', bound globally to `M-&'.
This executes the command asynchronously, similar to calling `M-!' and
manually adding an ampersand to the end of the command.  With `M-&',
you don't need the ampersand.  The output appears in the buffer
`*Async Shell Command*'.

** When running in a new enough xterm (newer than version 242), Emacs
asks xterm what the background color is and it sets up faces
accordingly for a dark background if needed (the current default is to
consider the background light).


* Editing Changes in Emacs 23.2

** Kill-ring and selection changes

*** If `select-active-regions' is t, any active region automatically
becomes the primary selection (for interaction with other window
applications).  If you enable this, you might want to bind
`mouse-yank-primary' to Mouse-2.

*** When `save-interprogram-paste-before-kill' is non-nil, the kill
commands save the interprogram-paste selection into the kill ring
before doing anything else.  This avoids losing the selection.

*** When `kill-do-not-save-duplicates' is non-nil, identical
subsequent kills are not duplicated in the `kill-ring'.

** Completion changes

*** The new command `completion-at-point' provides mode-sensitive completion.

*** tab-always-indent set to `complete' lets TAB do completion as well.

*** The new completion-style `initials' is available.
For instance, this can complete M-x lch to list-command-history.

*** The new variable `completions-format' determines how completions
are displayed in the *Completions* buffer.  If you set it to
`vertical', completions are sorted vertically in columns.

** The default value of `blink-matching-paren-distance' is increased.

** M-n provides more default values in the minibuffer for commands
that read file names.  These include the file name at point (when ffap
is loaded without ffap-bindings), the file name on the current line
(in Dired buffers), and the directory names of adjacent Dired windows
(for Dired commands that operate on several directories, such as copy,
rename, or diff).

** M-r is bound to the new `move-to-window-line-top-bottom'.
This moves point to the window center, top and bottom on successive
invocations, in the same spirit as the C-l (recenter-top-bottom)
command.

** The new variable `recenter-positions' determines the default
cycling order of C-l (`recenter-top-bottom').

** The abbrevs file is now a file named abbrev_defs in
user-emacs-directory; but the old location, ~/.abbrev_defs, is used if
that file exists.


* Changes in Specialized Modes and Packages in Emacs 23.2

** The bookmark menu has a narrowing search via bookmark-bmenu-search.

** Calc

*** The Calc settings file is now a file named calc.el in
user-emacs-directory; but the old location, ~/.calc.el, is used if
that file exists.

*** Graphing commands (`g f' etc.) now work on MS-Windows, if you have
the native Windows port of Gnuplot version 3.8 or later installed.

** Calendar and diary

*** Fancy diary display is now the default.
If you prefer the simple display, customize `diary-display-function'.

*** The diary's fancy display now enables view-mode.

*** The command `calendar-current-date' accepts an optional argument
giving an offset from today.

** Desktop

*** The default value for `desktop-buffers-not-to-save' is nil.
This means Desktop will try restoring all buffers, when you restart
your Emacs session.  Also, `desktop-buffers-not-to-save' is only
effective for buffers that have no associated file.  If you want to
exempt buffers that do correspond to files, customize the value of
`desktop-files-not-to-save' instead.

** Dired

*** The new variable `dired-auto-revert-buffer', if non-nil, causes
Dired buffers to be reverted automatically on revisiting them.

** DocView

*** When `doc-view-continuous' is non-nil, scrolling a line
on the page edge advances to the next/previous page.

** Elint

*** Elint now uses compilation-mode.

*** Elint can now scan individual files and whole directories,
and can be run in batch mode.

*** Elint does a more thorough initialization, and recognizes more built-in
functions and variables.  Customize `elint-scan-preloaded' if you want
to sacrifice some accuracy for a faster startup.

*** Elint attempts some basic understanding of featurep and (f)boundp tests.

*** Customize `elint-ignored-warnings' to suppress some warnings.

** GDB-UI

*** Toolbar functionality for reverse debugging.  Display of STL
collections as watch expressions.  These features require GDB 7.0 or later.

** Grep

*** A new command `zrgrep' searches recursively in gzipped files.

** Info

*** The new command `Info-virtual-index' bound to "I" displays a menu of
matched topics found in the index.

*** The new command `info-finder' replaces finder.el with a virtual Info
manual that generates an Info file which gives the same information
through a menu structure.

** LaTeX mode now provides completion (via completion-at-point).

** Message mode is now the default mode for composing mail.

The default for `mail-user-agent' is now message-user-agent, so the
C-x m (`compose-mail') command uses Message mode instead of Mail mode.

Message mode has been included in Emacs, as part of the Gnus package,
for several years.  It provides several features that are absent in
Mail mode, such as MIME handling.

*** If the user has not customized mail-user-agent, `compose-mail'
checks for Mail mode customizations, and issues a warning if these
customizations are found.  This alerts users who may otherwise be
unaware that their mail configuration has changed.

To disable this check, set compose-mail-user-agent-warnings to nil.

** The default value of mail-interactive is t, since Emacs 23.1.
(This was not announced at the time.)  It means that when sending mail,
Emacs will wait for the process sending mail to return.  If you
experience delays when sending mail, you may wish to set this to nil.

** nXML mode is now the default for editing XML files.

** pcomplete provides a new command `pcomplete-std-completion' which
is similar to `pcomplete' but using the standard completion UI code.

** Shell (and other comint modes)

*** M-s is no longer bound to `comint-next-matching-input'.

*** M-r is now bound to `comint-history-isearch-backward-regexp'.
This starts an incremental search of the comint/shell input history.

*** ansi-color is now enabled by default in Shell mode.
To disable it, set ansi-color-for-comint-mode to nil.

** Tramp

*** New connection methods "rsyncc", "imap" and "imaps".
On systems which support GVFS-Fuse, Tramp offers also the new
connection methods "dav", "davs", "obex" and "synce".

** VC and related modes

*** When using C-x v v or C-x v i on a unregistered file that is in a
directory not controlled by any VCS, ask the user what VC backend to
use to create a repository, create a new repository and register the
file.

*** New command `vc-root-print-log', bound to `C-x v L'.
This displays a `*vc-change-log*' buffer showing the history of the
version-controlled directory tree as a whole.

*** New command `vc-root-diff', bound to `C-x v D'.
This is similar to `vc-diff', but compares the entire directory tree
of the current VC directory with its working revision.

*** `C-x v l' and `C-x v L' do not show the full log by default.
The number of entries shown can be chosen interactively with a prefix
argument, or by customizing vc-log-show-limit.  The `*vc-change-log*'
buffer now contains buttons at the end of the buffer, which can be
used to increase the number of entries shown.  RCS, SCCS, and CVS do
not support this feature.

*** vc-annotate supports annotations through file copies and renames,
it displays the old names for the files and it can show logs/diffs for
the corresponding lines.  Currently only Git and Mercurial take
advantage of this feature.

*** The log command in vc-annotate can display a single log entry
instead of redisplaying the full log.  The RCS, CVS and SCCS VC
backends do not support this.

*** When a file is not found, VC will not try to check it out of RCS anymore.

*** Diff and log operations can be used from Dired buffers.

*** vc-git changes

**** The short log format for git makes use of the graph display,
so it's not supported on git versions earlier than 1.5.6.

**** vc-dir uses the --relative option of git, and so requires at least
git version 1.5.5.

**** Support for operating with stashes has been added to vc-dir:
the stash list is displayed in the *vc-dir* header, stashes can be
created, removed, applied and their content displayed.

*** vc-bzr supports operating with shelves: the shelve list is
displayed in the *vc-dir* header, shelves can be created, removed and applied.

*** log-edit-strip-single-file-name controls whether or not single filenames
are stripped when copying text from the ChangeLog to the *VC-Log* buffer.

** Miscellaneous

*** Interactively `multi-isearch-buffers' and `multi-isearch-buffers-regexp'
read buffer names to search, one by one, ended with RET.  With a prefix
argument, they ask for a regexp, and search in buffers whose names match
the specified regexp.  Interactively `multi-isearch-files' and
`multi-isearch-files-regexp' read file names to search, one by one,
ended with RET.  With a prefix argument, they ask for a wildcard, and
search in file buffers whose file names match the specified wildcard.

*** Autorevert Tail mode now works also for remote files.

*** The new eshell built-in commands `su' and `sudo' support Tramp.
Thus, they change `default-directory' to reflect the new user id, and
let commands run under that user's permissions.  This works even when
`default-directory' is already remote.  Calling the external commands
is possible via `*su' or `*sudo', respectively.

** Obsolete packages

*** sym-comp.el is now obsolete, superseded by completion-at-point.

*** lucid.el and levents.el are now obsolete.


* New Modes and Packages in Emacs 23.2

** CEDET (the Collection of Emacs Development Tools) is now in Emacs.
This is a collection of packages to aid with using Emacs as an IDE
(integrated development environment):

*** The Semantic package allows the use of parsers to intelligently
edit and navigate source code.  Parsers for C/C++, Java, Javascript,
and several other languages are included by default, and Semantic can
also interface with external tools such as GNU Global and GNU Idutils.

To enable Semantic, use the global minor mode `semantic-mode'.
See the Semantic manual for details.

*** EDE (Emacs Development Environment) is a package for managing code
projects, including features such as automatic Makefile generation.

To enable EDE, use the minor mode `global-ede-mode'.
See the EDE manual for details.

*** SRecode is a library for recoding Semantic tags back into source
code.  It is currently used by some parts of Semantic and EDE; in the
future, it may be used for code generation features.

*** The EIEIO library implements a subset of the Common Lisp Object
System (CLOS).  It is used by the other CEDET packages.

** mpc.el is a front end for the Music Player Daemon.  Run it with M-x mpc.

** htmlfontify.el turns a fontified Emacs buffer into an HTML page.

** js.el is a new major mode for JavaScript files.

** imap-hash.el is a new library to address IMAP mailboxes as hashtables.


* Incompatible Lisp Changes in Emacs 23.2

** The Lisp reader turns integers that are too large/small into floats.
For instance, on machines where `536870911' is the largest integer,
reading `536870912' gives the floating-point object `536870912.0'.

This change only concerns the Lisp reader; it does not affect how
actual integer objects overflow.

** Several obsolete functions removed.
The functions have been obsolete since Emacs 19, and are unlikely to
be in use:

  time-stamp-month-dd-yyyy, time-stamp-dd/mm/yyyy, time-stamp-mon-dd-yyyy
  time-stamp-dd-mon-yy, time-stamp-yy/mm/dd, time-stamp-yyyy/mm/dd,
  time-stamp-yyyy-mm-dd, time-stamp-yymmdd, time-stamp-hh:mm:ss,
  time-stamp-hhmm, baud-rate

** Support for generating Emacs 18 compatible bytecode (by setting
the variable `byte-compile-compatibility') has been removed.

** In image-mode.el `image-mode-maybe' is obsolete.
Instead, you can either use `image-mode' (which displays an image file
as the actual image initially), or `image-mode-as-text' (when you want
to display an image file as text initially).  `image-mode-as-text' is a
combination of a non-image mode from `auto-mode-alist' (or Fundamental
mode) and `image-minor-mode'.  `image-minor-mode' provides a `C-c C-c'
key binding to toggle image display.
`image-toggle-display-text' removes image properties.
`image-toggle-display-image' adds image properties.
`image-toggle-display' toggles between `image-mode-as-text' and `image-mode'.


* Lisp changes in Emacs 23.2

** All the default-FOO variables that hold the default value of the FOO
variable, are now declared obsolete.

** read-key is a function halfway between read-event and read-key-sequence.
It reads a single key, but obeys input and escape sequence decoding.

** Frame parameter changes

*** You can give the `fullscreen' frame parameter the value `maximized'.
This maximizes the frame.

*** The new frame parameter `sticky' makes Emacs frames sticky in
virtual desktops.

** Completion changes

*** completion-base-size is obsoleted by completion-base-position.
This change causes a few backward incompatibilities, mostly with
choose-completion-string-functions where the `mini-p' argument has
been replaced by a `base-position' argument, and where the `base-size'
argument is now always nil.

*** New function `completion-in-region' to use the standard completion
facilities on a particular region of text.

*** The 4th arg to all-completions (aka hide-spaces) is declared obsolete.

*** completion-annotate-function specifies how to compute annotations
for completions displayed in *Completions*.

** Minibuffer changes

*** read-file-name-predicate is obsolete.  It was used to pass the predicate
to read-file-name-internal because read-file-name-internal abused its `pred'
argument to pass the current directory, but this hack is not needed
any more.

** Changes to file-manipulation functions

*** `delete-directory' has an optional parameter RECURSIVE.

*** New function `copy-directory', which copies a directory recursively.

** called-interactively-p now takes one argument and replaces interactive-p
which is now marked obsolete.

** New function set-advertised-calling-convention makes it possible
to obsolete arguments as well as make some arguments mandatory.

** You can control which binding is preferentially shown in menus and
docstrings by adding a `:advertised-binding' property to the corresponding
command's symbol.  That property can hold a single binding or a list
of bindings.

** Network and process changes

*** start-process-shell-command and start-file-process-shell-command
now only take a single `command' argument.

*** The new variable `process-file-side-effects' should be set to nil
if a `process-file' call does not change a remote file.  This allows
file name handlers such as Tramp to optimizations.

*** make-network-process can now also create `seqpacket' Unix sockets.

** Loading changes

*** eval-next-after-load is obsolete.

*** New hook `after-load-functions' run after loading an Elisp file.

** Byte compilation changes

*** Changing the file-names generated by byte-compilation by redefining
the function `byte-compile-dest-file' before loading bytecomp.el is obsolete.
Instead, customize byte-compile-dest-file-function.

*** `byte-compile-warnings' has new members, `constants' and `suspicious'.

** New macro with-silent-modifications to tweak text properties without
affecting the buffer's modification state.

** Hash tables have a new printed representation that is readable.
The feature `hashtable-print-readable' identifies this new
functionality.

** New functions for performing Unicode normalization:
ucs-normalize-NFD-region, ucs-normalize-NFD-string,
ucs-normalize-NFC-region, ucs-normalize-NFC-string,
ucs-normalize-NFKD-region, ucs-normalize-NFKD-string,
ucs-normalize-NFKC-region, ucs-normalize-NFKC-string,
ucs-normalize-HFS-NFD-region, ucs-normalize-HFS-NFD-string,
ucs-normalize-HFS-NFC-region, ucs-normalize-HFS-NFC-string.

** Face aliases can now be marked as obsolete, using the macro
`define-obsolete-face-alias'.

** New function `window-full-height-p', analogous to the full-width version.


* Changes in Emacs 23.2 on non-free operating systems

** On MS-Windows, `display-time' now displays the system load average
as well as the time, as it does on GNU and Unix.


* Installation Changes in Emacs 23.1

** The default X toolkit is now Gtk+, rather than Lucid.
The configure option `--with-gtk' has been removed.  Gtk is now the
default toolkit, but you can use --with-x-toolkit=gtk if necessary.

** New font code.
Fonts are handled by new code capable of dealing with multiple font
backends.  This uses the freetype and fontconfig libraries.

*** Emacs now accepts font names supplied in the fontconfig format
(e.g. "monospace-12:bold") and GTK format (e.g. "Monospace Bold 12").

*** Added support for local fonts (fonts installed on the machine
where Emacs is running).

*** Added support for the Xft library for antialiasing.

*** Added support for the otf library for complex text layout by
OpenType fonts.

*** Added support for the m17n library for text shaping.

** Changes to image support

*** configure now checks for libgif before libungif when searching for
a GIF library.

*** Emacs now supports the SVG image format through librsvg2.

*** Emacs now supports multi-page TIFF images.

** New NeXTSTEP-based port.
This provides support for GNUstep (via the GNUstep libraries) and Mac
OS X (via the Cocoa libraries).

Specify --with-ns to configure for this.  By default, a self-contained
app will be built (containing all lisp).  To install/share lisp with
other emacsen (e.g. X11 build) use --disable-ns-self-contained.  See
nextstep/README and nextstep/INSTALL in the Emacs source directory.

** Mac OS X is no longer supported via Carbon.
Use the NeXTSTEP port, described above.

** The new configuration option "--with-dbus" enables D-Bus language
bindings for Emacs.

** Support for many obsolete platforms has been removed.
See the list at the end of etc/MACHINES for details.

*** Support for systems without alloca has been removed.

*** Support for Sun windows has been removed.

*** The `emacstool' utility has been removed.

** The following platforms will be removed in a future Emacs version:
If you are still using Emacs on one of these platforms, please email
emacs-devel@gnu.org to inform the Emacs developers.

*** Old GNU/Linux systems based on libc version 5.

*** Old FreeBSD, NetBSD, and OpenBSD systems based on the COFF
executable format.

*** Solaris versions 2.6 and below.

*** Solaris on IBM RS6000 machines.

*** UNIX System V (the original SysV, not later platforms based on it).

*** Unixware on non-x86 machines.

*** Platforms not supporting shared libraries (i.e., requiring the
NO_SHARED_LIBS compilation flag).

** The configure options `--with-gcc', `--without-gcc' have been removed.
Configure will use gcc by default.  Set the CC environment variable if
you need control over which C compiler is used.

** The refcards are now shipped as PDF files.

** The manuals are now licensed under the GNU Free Documentation License v1.3,
or any later version.

** Emacs 23 comes with a new set of default icons.
Various resolutions are available as etc/images/icons/hicolor/*/apps/emacs.png.
The Emacs 22 icon is available as `emacs22.png' in the same location.

* Changes in Emacs 23.1

** Improved X Window System support

*** Emacs now supports using both X displays and ttys in one session.
With an Emacs server active (M-x server-start), `emacsclient -t'
creates a tty frame connected to the running emacs server.  You can
use any number of different ttys.  `emacsclient -c' creates a new X11
frame on the current $DISPLAY (or a tty frame if $DISPLAY is not set).
There may be problems if a display exits unexpectedly and Emacs is compiled
with Gtk+, see etc/PROBLEMS.

You can test for the presence of this feature in your Lisp code by
testing for the `multi-tty' feature.

*** Emacs starts in the background, as a daemon, when given the
--daemon command line argument.  It disconnects from the terminal and
starts the server.  Clients can connect and create graphical or
terminal frames using emacsclient.

**** emacsclient starts emacs in daemon mode and connects to it when
--alternate-editor="" is used (or when the evironment variable
ALTERNATE_EDITOR is set to "") and emacsclient cannot connect to an
emacs server.

*** The new command close-display-connection closes a connection to a
remote display.  There are some bugs for Gtk+.  See etc/PROBLEMS.

*** Emacs now supports the XEmbed specification.
You can embed Emacs in another application on X11.  The new command line
option --parent-id is used to pass the parent window id to Emacs.  See
http://standards.freedesktop.org/xembed-spec/xembed-spec-latest.html
for details about XEmbed.

*** Emacs can now set the frame opacity.
The opacity of a frame can be controlled by setting the `alpha' frame
parameter.  This only takes effect on a compositing window manager for
the X Window System, such as Compiz, Beryl and Compiz Fusion, on Mac
OS X, or on Windows 2000 and later versions of Windows.

The alpha parameter should be an integer between 0 (transparent) and
100 (opaque), or a float number between 0.0 and 1.0.  It can also be a
cons cell (ACTIVE . INACTIVE), where ACTIVE is the opacity of an
active frame and INACTIVE is the opacity of non-active frames.

The variable `frame-alpha-lower-limit' defines a lower bound for the
opacity; the default is 20.

** Internationalization changes

*** The Emacs character set is now a superset of Unicode.
(It has about four times the code space, which should be plenty).

The internal encoding used for buffers and strings is now
Unicode-based and called `utf-8-emacs' (`emacs-internal' is an alias
for this).  This encoding is backward-compatible with Unicode's UTF-8
encoding.  The internal encoding previously used by Emacs,
`emacs-mule', is still available for reading and writing files.

During byte-compilation, Emacs 23 uses `utf-8-emacs' to write files.
As a result, byte-compiled files containing non-ASCII characters can't
be read by earlier versions of Emacs.  Files compiled by Emacs 20, 21,
or 22 are loaded correctly as `emacs-mule' (whether or not they
contain multibyte characters).  This takes somewhat more time, so it
may be worth recompiling existing .elc files which don't need to be
shared with older Emacsen.

*** There are new coding systems/aliases; see M-x list-coding-systems.

*** There is a new charset implementation with many new charsets.
See M-x list-character-sets.  New charsets can be defined conveniently
as tables of unicodes.

*** There are new language environments for Chinese-GBK,
Chinese-GB18030, Khmer, Bengali, Punjabi, Gujarati, Oriya, Telugu,
Sinhala, and TaiViet.

*** The minor modes unify-8859-on-encoding-mode and
unify-8859-on-decoding-mode are obsolete.

*** `ucs-insert' is bound to `C-x 8 RET' and in addition to hex numbers
accepts numbers in hash notation (e.g. #o21430 for octal, or #10r8984 for
decimal).  It also accepts Unicode character names with completion.

*** The `cyrillic-translit' input method supports many new characters.
Common typographical characters available from Unicode were added to
`cyrillic-translit': punctuation marks, accented characters, fractions,
and others.

** Emacs now supports serial port access on GNU/Linux, Unix, and
Windows.  The new command `serial-term' starts an interactive terminal
on a serial port.  The serial port can be configured at runtime with
the mode-line mouse menu.

** Menu Bar changes

*** In the Options menu, the "Set Default Font" item applies the
selected font to the `default' face on all frames, not just the
current frame.  Furthermore, if Emacs is compiled with both GTK and
Fontconfig support, the "Set Default Font" item uses the GTK font
selection dialog instead of an Emacs pop-up menu.

*** The font setting chosen by "Set Default Font" is saved if the
"Save Options" item is used.

*** The Tools menu contains a new Encryption/Decryption submenu.
This contains commands provided by EasyPG, the newly-included
interface to GnuPG (see New Modes and Packages).

*** In the Options menu, the "Truncate Long Lines in the Buffer" entry
has been replaced with a submenu offering three different ways to
handle long lines: truncation, continuation at the window edge, and
the new word wrapping behavior (see Editing Changes, below).

*** Improvements to menus for major and minor modes
More major and minor modes now have a mode specific menu, and existing
mode menus have been improved to include more functionality.

** Mode-line changes

*** The mode-line displays a `@', instead of `-', if the
default-directory for the current buffer is on a remote machine.

*** The mode-line displays a mode menu when mouse-1 is clicked on a
minor mode, in the same way as it already did for major modes.

*** The `mode-line-emphasis' face is used to highlight certain
mode-line information (e.g. waiting for a VC command to finish).

*** The mode-line tooltips have been improved to provide more details.

*** The VC, line/colum number and minor mode indicators on the mode
line are now interactive: mouse-1 can be used on them to pop up a menu.

** File deletion can make use of the Recycle Bin or system Trash folder.
Set `delete-by-moving-to-trash' non-nil to use this.  Deleted files
and directories will then be sent to the Recycle Bin on Windows, and
to `trash-directory' on other systems.

** Directory-local variables can now be defined.
By default, Emacs looks in .dir-locals.el for directory-local
variables.  For more information, see `dir-locals-set-directory-class'
and `dir-locals-set-class-variables'.

** Emacs can now use `auth-source' for authentication.
`smtpmail' and `url' (Tramp and Gnus also) use `auth-source' to obtain
login names and passwords.  The match, if found, is reported
in *Messages* with the password blanked out.

** `where-is-preferred-modifier' can specify your favorite modifier.


* Startup Changes in Emacs 23.1

** The option `inhibit-startup-screen' (with aliases to old names
`inhibit-splash-screen' and `inhibit-startup-message') doesn't inhibit
display of the initial message in the *scratch* buffer.  If you don't
want to display the initial message in the *scratch* buffer at startup,
you can set the option `initial-scratch-message' to nil.

** New user option `initial-buffer-choice' specifies what to display
after starting Emacs: startup screen, *scratch* buffer, visiting a
file or directory.

** New alias `argv' for `command-line-args-left'
This is a convenience alias, so that one can write `(pop argv)'
inside of --eval command line arguments in order to access
following arguments.

** The abbrev file is no longer read at startup in batch mode.

** Emacs now supports invocation by an X session manager.
It can save a session and restore it later.  See the documentation of
the functions `emacs-session-save' and `emacs-session-restore'.
(Actually, this feature was introduced with Emacs 22, but it was not
documented.)

* Incompatible Editing Changes in Emacs 23.1

** In Dired, `dired-flag-garbage-files' is rebound from `&' to `%&'
on the regexp command prefix map.

** In Dired-x, all command guesses for ! are now added to the default
list accessible by M-n instead of pushing all guesses temporarily into
the history list.

** In Isearch mode, a special case of typing `C-w' at the beginning of
the minibuffer that toggles word search (i.e. using key sequences
`C-s RET C-w' or `C-s M-e C-w') is obsolete.  You can use the global key
`M-s w' to start word search, or type `M-s w' in Isearch mode to
toggle word search.  To start nonincremental word search you can now use
`M-s w RET' and `M-s w C-r RET' instead of `C-s RET C-w' and `C-r RET C-w'.

** In Info, `Info-search' is unbound from `M-s' to allow using `M-s w'
for word search as well as other search commands from the global prefix
key `M-s'.  `Info-search' is still bound to `s', and also incremental
search commands `C-s', `C-M-s', `C-r', `C-M-r' are available for searching
through multiple Info nodes, together with their nonincremental versions
`C-s RET', `C-r RET', `C-M-s RET', `C-M-r RET', `M-s w RET'.

** In Text mode, `center-line' and `center-paragraph' are rebound from
`M-s' and `M-S' to global keys `M-o M-s' and `M-o M-S' on the global
prefix map `M-o', which is intended for such formatting commands.

** The following input methods were removed in Emacs 22.2, but this was
not advertised: danish-alt-postfix, esperanto-alt-postfix,
finnish-alt-postfix, german-alt-postfix, icelandic-alt-postfix,
norwegian-alt-postfix, scandinavian-alt-postfix, spanish-alt-postfix,
and swedish-alt-postfix.  Use the versions without "alt-", which are
identical.


* Editing Changes in Emacs 23.1

** The C-n and C-p line-motion commands now move by screen lines,
taking continued lines and variable-width characters into account.
Setting `line-move-visual' to nil reverts this to the previous
behavior (i.e., motion by logical lines based on buffer contents
alone).

** C-x C-c now invokes `save-buffers-kill-terminal', and C-z now
invokes `suspend-frame'.  These changes are for compatibility with the
new multi-tty support (see `Improved X Window System support' above).

** Mark changes