[Emacs-diffs] Changes to mule.texi

[Glenn Morris]

CVSROOT:        /sources/emacs
Module name:    emacs
Changes by:     Glenn Morris <gm>       07/09/06 04:47:57

Index: mule.texi
===================================================================
RCS file: mule.texi
diff -N mule.texi
--- /dev/null   1 Jan 1970 00:00:00 -0000
+++ mule.texi   6 Sep 2007 04:47:57 -0000       1.1
@@ -0,0 +1,1535 @@
address@hidden This is part of the Emacs manual.
address@hidden Copyright (C) 1997, 1999, 2000, 2001, 2002, 2003, 2004,
address@hidden   2005, 2006, 2007 Free Software Foundation, Inc.
address@hidden See file emacs.texi for copying conditions.
address@hidden International, Major Modes, Frames, Top
address@hidden International Character Set Support
address@hidden MULE
address@hidden international scripts
address@hidden multibyte characters
address@hidden encoding of characters
+
address@hidden Celtic
address@hidden Chinese
address@hidden Cyrillic
address@hidden Czech
address@hidden Devanagari
address@hidden Hindi
address@hidden Marathi
address@hidden Ethiopic
address@hidden German
address@hidden Greek
address@hidden Hebrew
address@hidden IPA
address@hidden Japanese
address@hidden Korean
address@hidden Lao
address@hidden Latin
address@hidden Polish
address@hidden Romanian
address@hidden Slovak
address@hidden Slovenian
address@hidden Thai
address@hidden Tibetan
address@hidden Turkish
address@hidden Vietnamese
address@hidden Dutch
address@hidden Spanish
+  Emacs supports a wide variety of international character sets,
+including European and Vietnamese variants of the Latin alphabet, as
+well as Cyrillic, Devanagari (for Hindi and Marathi), Ethiopic, Greek,
+Han (for Chinese and Japanese), Hangul (for Korean), Hebrew, IPA,
+Kannada, Lao, Malayalam, Tamil, Thai, Tibetan, and Vietnamese scripts.
+Emacs also supports various encodings of these characters used by
+other internationalized software, such as word processors and mailers.
+
+  Emacs allows editing text with international characters by supporting
+all the related activities:
+
address@hidden @bullet
address@hidden
+You can visit files with address@hidden characters, save address@hidden text, 
and
+pass address@hidden text between Emacs and programs it invokes (such as
+compilers, spell-checkers, and mailers).  Setting your language
+environment (@pxref{Language Environments}) takes care of setting up the
+coding systems and other options for a specific language or culture.
+Alternatively, you can specify how Emacs should encode or decode text
+for each command; see @ref{Text Coding}.
+
address@hidden
+You can display address@hidden characters encoded by the various
+scripts.  This works by using appropriate fonts on graphics displays
+(@pxref{Defining Fontsets}), and by sending special codes to text-only
+displays (@pxref{Terminal Coding}).  If some characters are displayed
+incorrectly, refer to @ref{Undisplayable Characters}, which describes
+possible problems and explains how to solve them.
+
address@hidden
+You can insert address@hidden characters or search for them.  To do that,
+you can specify an input method (@pxref{Select Input Method}) suitable
+for your language, or use the default input method set up when you set
+your language environment.  If
+your keyboard can produce address@hidden characters, you can select an
+appropriate keyboard coding system (@pxref{Terminal Coding}), and Emacs
+will accept those characters.  Latin-1 characters can also be input by
+using the @kbd{C-x 8} prefix, see @ref{Unibyte Mode}.
+
+On X Window systems, your locale should be set to an appropriate value
+to make sure Emacs interprets keyboard input correctly; see
address@hidden Environments, locales}.
address@hidden itemize
+
+  The rest of this chapter describes these issues in detail.
+
address@hidden
+* International Chars::     Basic concepts of multibyte characters.
+* Enabling Multibyte::      Controlling whether to use multibyte characters.
+* Language Environments::   Setting things up for the language you use.
+* Input Methods::           Entering text characters not on your keyboard.
+* Select Input Method::     Specifying your choice of input methods.
+* Multibyte Conversion::    How single-byte characters convert to multibyte.
+* Coding Systems::          Character set conversion when you read and
+                              write files, and so on.
+* Recognize Coding::        How Emacs figures out which conversion to use.
+* Specify Coding::          Specifying a file's coding system explicitly.
+* Output Coding::           Choosing coding systems for output.
+* Text Coding::             Choosing conversion to use for file text.
+* Communication Coding::    Coding systems for interprocess communication.
+* File Name Coding::        Coding systems for file @emph{names}.
+* Terminal Coding::         Specifying coding systems for converting
+                              terminal input and output.
+* Fontsets::                Fontsets are collections of fonts
+                              that cover the whole spectrum of characters.
+* Defining Fontsets::       Defining a new fontset.
+* Undisplayable Characters:: When characters don't display.
+* Unibyte Mode::            You can pick one European character set
+                              to use without multibyte characters.
+* Charsets::                How Emacs groups its internal character codes.
address@hidden menu
+
address@hidden International Chars
address@hidden Introduction to International Character Sets
+
+  The users of international character sets and scripts have
+established many more-or-less standard coding systems for storing
+files.  Emacs internally uses a single multibyte character encoding,
+so that it can intermix characters from all these scripts in a single
+buffer or string.  This encoding represents each address@hidden
+character as a sequence of bytes in the range 0200 through 0377.
+Emacs translates between the multibyte character encoding and various
+other coding systems when reading and writing files, when exchanging
+data with subprocesses, and (in some cases) in the @kbd{C-q} command
+(@pxref{Multibyte Conversion}).
+
address@hidden C-h h
address@hidden view-hello-file
address@hidden undisplayable characters
address@hidden @samp{?} in display
+  The command @kbd{C-h h} (@code{view-hello-file}) displays the file
address@hidden/HELLO}, which shows how to say ``hello'' in many languages.
+This illustrates various scripts.  If some characters can't be
+displayed on your terminal, they appear as @samp{?} or as hollow boxes
+(@pxref{Undisplayable Characters}).
+
+  Keyboards, even in the countries where these character sets are used,
+generally don't have keys for all the characters in them.  So Emacs
+supports various @dfn{input methods}, typically one for each script or
+language, to make it convenient to type them.
+
address@hidden C-x RET
+  The prefix key @kbd{C-x @key{RET}} is used for commands that pertain
+to multibyte characters, coding systems, and input methods.
+
address@hidden Enabling Multibyte
address@hidden Enabling Multibyte Characters
+
+  By default, Emacs starts in multibyte mode, because that allows you to
+use all the supported languages and scripts without limitations.
+
address@hidden turn multibyte support on or off
+  You can enable or disable multibyte character support, either for
+Emacs as a whole, or for a single buffer.  When multibyte characters
+are disabled in a buffer, we call that @dfn{unibyte mode}.  Then each
+byte in that buffer represents a character, even codes 0200 through
+0377.
+
+  The old features for supporting the European character sets, ISO
+Latin-1 and ISO Latin-2, work in unibyte mode as they did in Emacs 19
+and also work for the other ISO 8859 character sets.  However, there
+is no need to turn off multibyte character support to use ISO Latin;
+the Emacs multibyte character set includes all the characters in these
+character sets, and Emacs can translate automatically to and from the
+ISO codes.
+
+  To edit a particular file in unibyte representation, visit it using
address@hidden  @xref{Visiting}.  To convert a buffer in
+multibyte representation into a single-byte representation of the same
+characters, the easiest way is to save the contents in a file, kill the
+buffer, and find the file again with @code{find-file-literally}.  You
+can also use @kbd{C-x @key{RET} c}
+(@code{universal-coding-system-argument}) and specify @samp{raw-text} as
+the coding system with which to find or save a file.  @xref{Text
+Coding}.  Finding a file as @samp{raw-text} doesn't disable format
+conversion, uncompression and auto mode selection as
address@hidden does.
+
address@hidden enable-multibyte-characters
address@hidden default-enable-multibyte-characters
+  To turn off multibyte character support by default, start Emacs with
+the @samp{--unibyte} option (@pxref{Initial Options}), or set the
+environment variable @env{EMACS_UNIBYTE}.  You can also customize
address@hidden or, equivalently, directly set the
+variable @code{default-enable-multibyte-characters} to @code{nil} in
+your init file to have basically the same effect as @samp{--unibyte}.
+
address@hidden toggle-enable-multibyte-characters
+  To convert a unibyte session to a multibyte session, set
address@hidden to @code{t}.  Buffers which
+were created in the unibyte session before you turn on multibyte support
+will stay unibyte.  You can turn on multibyte support in a specific
+buffer by invoking the command @code{toggle-enable-multibyte-characters}
+in that buffer.
+
address@hidden Lisp files, and multibyte operation
address@hidden multibyte operation, and Lisp files
address@hidden unibyte operation, and Lisp files
address@hidden init file, and address@hidden characters
address@hidden environment variables, and address@hidden characters
+  With @samp{--unibyte}, multibyte strings are not created during
+initialization from the values of environment variables,
address@hidden/etc/passwd} entries etc.@: that contain address@hidden 8-bit
+characters.
+
+  Emacs normally loads Lisp files as multibyte, regardless of whether
+you used @samp{--unibyte}.  This includes the Emacs initialization file,
address@hidden, and the initialization files of Emacs packages such as
+Gnus.  However, you can specify unibyte loading for a particular Lisp
+file, by putting @address@hidden: t;-*-}} in a comment on the first
+line (@pxref{File Variables}).  Then that file is always loaded as
+unibyte text, even if you did not start Emacs with @samp{--unibyte}.
+The motivation for these conventions is that it is more reliable to
+always load any particular Lisp file in the same way.  However, you can
+load a Lisp file as unibyte, on any one occasion, by typing @kbd{C-x
address@hidden c raw-text @key{RET}} immediately before loading it.
+
+  The mode line indicates whether multibyte character support is
+enabled in the current buffer.  If it is, there are two or more
+characters (most often two dashes) near the beginning of the mode
+line, before the indication of the visited file's end-of-line
+convention (colon, backslash, etc.).  When multibyte characters
+are not enabled, nothing precedes the colon except a single dash.
address@hidden Line}, for more details about this.
+
address@hidden Language Environments
address@hidden Language Environments
address@hidden language environments
+
+  All supported character sets are supported in Emacs buffers whenever
+multibyte characters are enabled; there is no need to select a
+particular language in order to display its characters in an Emacs
+buffer.  However, it is important to select a @dfn{language environment}
+in order to set various defaults.  The language environment really
+represents a choice of preferred script (more or less) rather than a
+choice of language.
+
+  The language environment controls which coding systems to recognize
+when reading text (@pxref{Recognize Coding}).  This applies to files,
+incoming mail, netnews, and any other text you read into Emacs.  It may
+also specify the default coding system to use when you create a file.
+Each language environment also specifies a default input method.
+
address@hidden set-language-environment
address@hidden current-language-environment
+  To select a language environment, you can customize the variable
address@hidden or use the command @kbd{M-x
+set-language-environment}.  It makes no difference which buffer is
+current when you use this command, because the effects apply globally to
+the Emacs session.  The supported language environments include:
+
address@hidden Euro sign
address@hidden UTF-8
address@hidden
+ASCII, Belarusian, Brazilian Portuguese, Bulgarian, Chinese-BIG5,
+Chinese-CNS, Chinese-EUC-TW, Chinese-GB, Croatian, Cyrillic-ALT,
+Cyrillic-ISO, Cyrillic-KOI8, Czech, Devanagari, Dutch, English,
+Esperanto, Ethiopic, French, Georgian, German, Greek, Hebrew, IPA,
+Italian, Japanese, Kannada, Korean, Lao, Latin-1, Latin-2, Latin-3,
+Latin-4, Latin-5, Latin-6, Latin-7, Latin-8 (Celtic), Latin-9 (updated
+Latin-1 with the Euro sign), Latvian, Lithuanian, Malayalam, Polish,
+Romanian, Russian, Slovak, Slovenian, Spanish, Swedish, Tajik, Tamil,
+Thai, Tibetan, Turkish, UTF-8 (for a setup which prefers Unicode
+characters and files encoded in UTF-8), Ukrainian, Vietnamese, Welsh,
+and Windows-1255 (for a setup which prefers Cyrillic characters and
+files encoded in Windows-1255).
address@hidden
+\hbadness=10000\par  % just avoid underfull hbox warning
address@hidden tex
address@hidden quotation
+
address@hidden fonts for various scripts
address@hidden Intlfonts package, installation
+  To display the script(s) used by your language environment on a
+graphical display, you need to have a suitable font.  If some of the
+characters appear as empty boxes, you should install the GNU Intlfonts
+package, which includes fonts for most supported address@hidden
+you run Emacs on X, you need to inform the X server about the location
+of the newly installed fonts with the following commands:
+
address@hidden
+ xset fp+ /usr/local/share/emacs/fonts
+ xset fp rehash
address@hidden example
+}
address@hidden, for more details about setting up your fonts.
+
address@hidden set-locale-environment
address@hidden locale-language-names
address@hidden locale-charset-language-names
address@hidden locales
+  Some operating systems let you specify the character-set locale you
+are using by setting the locale environment variables @env{LC_ALL},
address@hidden, or @address@hidden more than one of these is
+set, the first one that is nonempty specifies your locale for this
+purpose.}  During startup, Emacs looks up your character-set locale's
+name in the system locale alias table, matches its canonical name
+against entries in the value of the variables
address@hidden and @code{locale-language-names},
+and selects the corresponding language environment if a match is found.
+(The former variable overrides the latter.)  It also adjusts the display
+table and terminal coding system, the locale coding system, the
+preferred coding system as needed for the locale, and---last but not
+least---the way Emacs decodes address@hidden characters sent by your keyboard.
+
+  If you modify the @env{LC_ALL}, @env{LC_CTYPE}, or @env{LANG}
+environment variables while running Emacs, you may want to invoke the
address@hidden function afterwards to readjust the
+language environment from the new locale.
+
address@hidden locale-preferred-coding-systems
+  The @code{set-locale-environment} function normally uses the preferred
+coding system established by the language environment to decode system
+messages.  But if your locale matches an entry in the variable
address@hidden, Emacs uses the corresponding
+coding system instead.  For example, if the locale @samp{ja_JP.PCK}
+matches @code{japanese-shift-jis} in
address@hidden, Emacs uses that encoding even
+though it might normally use @code{japanese-iso-8bit}.
+
+  You can override the language environment chosen at startup with
+explicit use of the command @code{set-language-environment}, or with
+customization of @code{current-language-environment} in your init
+file.
+
address@hidden C-h L
address@hidden describe-language-environment
+  To display information about the effects of a certain language
+environment @var{lang-env}, use the command @kbd{C-h L @var{lang-env}
address@hidden (@code{describe-language-environment}).  This tells you
+which languages this language environment is useful for, and lists the
+character sets, coding systems, and input methods that go with it.  It
+also shows some sample text to illustrate scripts used in this
+language environment.  If you give an empty input for @var{lang-env},
+this command describes the chosen language environment.
+
address@hidden set-language-environment-hook
+  You can customize any language environment with the normal hook
address@hidden  The command
address@hidden runs that hook after setting up the new
+language environment.  The hook functions can test for a specific
+language environment by checking the variable
address@hidden  This hook is where you should
+put non-default settings for specific language environment, such as
+coding systems for keyboard input and terminal output, the default
+input method, etc.
+
address@hidden exit-language-environment-hook
+  Before it starts to set up the new language environment,
address@hidden first runs the hook
address@hidden  This hook is useful for undoing
+customizations that were made with @code{set-language-environment-hook}.
+For instance, if you set up a special key binding in a specific language
+environment using @code{set-language-environment-hook}, you should set
+up @code{exit-language-environment-hook} to restore the normal binding
+for that key.
+
address@hidden Input Methods
address@hidden Input Methods
+
address@hidden input methods
+  An @dfn{input method} is a kind of character conversion designed
+specifically for interactive input.  In Emacs, typically each language
+has its own input method; sometimes several languages which use the same
+characters can share one input method.  A few languages support several
+input methods.
+
+  The simplest kind of input method works by mapping @acronym{ASCII} letters
+into another alphabet; this allows you to use one other alphabet
+instead of @acronym{ASCII}.  The Greek and Russian input methods
+work this way.
+
+  A more powerful technique is composition: converting sequences of
+characters into one letter.  Many European input methods use composition
+to produce a single address@hidden letter from a sequence that consists of a
+letter followed by accent characters (or vice versa).  For example, some
+methods convert the sequence @kbd{a'} into a single accented letter.
+These input methods have no special commands of their own; all they do
+is compose sequences of printing characters.
+
+  The input methods for syllabic scripts typically use mapping followed
+by composition.  The input methods for Thai and Korean work this way.
+First, letters are mapped into symbols for particular sounds or tone
+marks; then, sequences of these which make up a whole syllable are
+mapped into one syllable sign.
+
+  Chinese and Japanese require more complex methods.  In Chinese input
+methods, first you enter the phonetic spelling of a Chinese word (in
+input method @code{chinese-py}, among others), or a sequence of
+portions of the character (input methods @code{chinese-4corner} and
address@hidden, and others).  One input sequence typically
+corresponds to many possible Chinese characters.  You select the one
+you mean using keys such as @kbd{C-f}, @kbd{C-b}, @kbd{C-n},
address@hidden, and digits, which have special meanings in this situation.
+
+  The possible characters are conceptually arranged in several rows,
+with each row holding up to 10 alternatives.  Normally, Emacs displays
+just one row at a time, in the echo area; @code{(@var{i}/@var{j})}
+appears at the beginning, to indicate that this is the @var{i}th row
+out of a total of @var{j} rows.  Type @kbd{C-n} or @kbd{C-p} to
+display the next row or the previous row.
+
+    Type @kbd{C-f} and @kbd{C-b} to move forward and backward among
+the alternatives in the current row.  As you do this, Emacs highlights
+the current alternative with a special color; type @address@hidden
+to select the current alternative and use it as input.  The
+alternatives in the row are also numbered; the number appears before
+the alternative.  Typing a digit @var{n} selects the @var{n}th
+alternative of the current row and uses it as input.
+
+  @key{TAB} in these Chinese input methods displays a buffer showing
+all the possible characters at once; then clicking @kbd{Mouse-2} on
+one of them selects that alternative.  The keys @kbd{C-f}, @kbd{C-b},
address@hidden, @kbd{C-p}, and digits continue to work as usual, but they
+do the highlighting in the buffer showing the possible characters,
+rather than in the echo area.
+
+  In Japanese input methods, first you input a whole word using
+phonetic spelling; then, after the word is in the buffer, Emacs
+converts it into one or more characters using a large dictionary.  One
+phonetic spelling corresponds to a number of different Japanese words;
+to select one of them, use @kbd{C-n} and @kbd{C-p} to cycle through
+the alternatives.
+
+  Sometimes it is useful to cut off input method processing so that the
+characters you have just entered will not combine with subsequent
+characters.  For example, in input method @code{latin-1-postfix}, the
+sequence @kbd{e '} combines to form an @samp{e} with an accent.  What if
+you want to enter them as separate characters?
+
+  One way is to type the accent twice; this is a special feature for
+entering the separate letter and accent.  For example, @kbd{e ' '} gives
+you the two characters @samp{e'}.  Another way is to type another letter
+after the @kbd{e}---something that won't combine with that---and
+immediately delete it.  For example, you could type @kbd{e e @key{DEL}
+'} to get separate @samp{e} and @samp{'}.
+
+  Another method, more general but not quite as easy to type, is to use
address@hidden C-\} between two characters to stop them from combining.  This
+is the command @kbd{C-\} (@code{toggle-input-method}) used twice.
address@hidden
address@hidden Input Method}.
address@hidden ifnottex
+
address@hidden incremental search, input method interference
+  @kbd{C-\ C-\} is especially useful inside an incremental search,
+because it stops waiting for more characters to combine, and starts
+searching for what you have already entered.
+
+  To find out how to input the character after point using the current
+input method, type @kbd{C-u C-x =}.  @xref{Position Info}.
+
address@hidden input-method-verbose-flag
address@hidden input-method-highlight-flag
+  The variables @code{input-method-highlight-flag} and
address@hidden control how input methods explain
+what is happening.  If @code{input-method-highlight-flag} is
address@hidden, the partial sequence is highlighted in the buffer (for
+most input methods---some disable this feature).  If
address@hidden is address@hidden, the list of
+possible characters to type next is displayed in the echo area (but
+not when you are in the minibuffer).
+
address@hidden Select Input Method
address@hidden Selecting an Input Method
+
address@hidden @kbd
address@hidden C-\
+Enable or disable use of the selected input method.
+
address@hidden C-x @key{RET} C-\ @var{method} @key{RET}
+Select a new input method for the current buffer.
+
address@hidden C-h I @var{method} @key{RET}
address@hidden C-h C-\ @var{method} @key{RET}
address@hidden describe-input-method
address@hidden C-h I
address@hidden C-h C-\
+Describe the input method @var{method} (@code{describe-input-method}).
+By default, it describes the current input method (if any).  This
+description should give you the full details of how to use any
+particular input method.
+
address@hidden M-x list-input-methods
+Display a list of all the supported input methods.
address@hidden table
+
address@hidden set-input-method
address@hidden current-input-method
address@hidden C-x RET C-\
+  To choose an input method for the current buffer, use @kbd{C-x
address@hidden C-\} (@code{set-input-method}).  This command reads the
+input method name from the minibuffer; the name normally starts with the
+language environment that it is meant to be used with.  The variable
address@hidden records which input method is selected.
+
address@hidden toggle-input-method
address@hidden C-\
+  Input methods use various sequences of @acronym{ASCII} characters to
+stand for address@hidden characters.  Sometimes it is useful to
+turn off the input method temporarily.  To do this, type @kbd{C-\}
+(@code{toggle-input-method}).  To reenable the input method, type
address@hidden again.
+
+  If you type @kbd{C-\} and you have not yet selected an input method,
+it prompts for you to specify one.  This has the same effect as using
address@hidden @key{RET} C-\} to specify an input method.
+
+  When invoked with a numeric argument, as in @kbd{C-u C-\},
address@hidden always prompts you for an input method,
+suggesting the most recently selected one as the default.
+
address@hidden default-input-method
+  Selecting a language environment specifies a default input method for
+use in various buffers.  When you have a default input method, you can
+select it in the current buffer by typing @kbd{C-\}.  The variable
address@hidden specifies the default input method
+(@code{nil} means there is none).
+
+  In some language environments, which support several different input
+methods, you might want to use an input method different from the
+default chosen by @code{set-language-environment}.  You can instruct
+Emacs to select a different default input method for a certain
+language environment, if you wish, by using
address@hidden (@pxref{Language Environments,
+set-language-environment-hook}).  For example:
+
address@hidden
+(defun my-chinese-setup ()
+  "Set up my private Chinese environment."
+  (if (equal current-language-environment "Chinese-GB")
+      (setq default-input-method "chinese-tonepy")))
+(add-hook 'set-language-environment-hook 'my-chinese-setup)
address@hidden lisp
+
address@hidden
+This sets the default input method to be @code{chinese-tonepy}
+whenever you choose a Chinese-GB language environment.
+
address@hidden quail-set-keyboard-layout
+  Some input methods for alphabetic scripts work by (in effect)
+remapping the keyboard to emulate various keyboard layouts commonly used
+for those scripts.  How to do this remapping properly depends on your
+actual keyboard layout.  To specify which layout your keyboard has, use
+the command @kbd{M-x quail-set-keyboard-layout}.
+
address@hidden quail-show-key
+  You can use the command @kbd{M-x quail-show-key} to show what key (or
+key sequence) to type in order to input the character following point,
+using the selected keyboard layout.  The command @kbd{C-u C-x =} also
+shows that information in addition to the other information about the
+character.
+
address@hidden list-input-methods
+  To see a list of all the supported input methods, type @kbd{M-x
+list-input-methods}.  The list gives information about each input
+method, including the string that stands for it in the mode line.
+
address@hidden Multibyte Conversion
address@hidden Unibyte and Multibyte address@hidden characters
+
+  When multibyte characters are enabled, character codes 0240 (octal)
+through 0377 (octal) are not really legitimate in the buffer.  The valid
address@hidden printing characters have codes that start from 0400.
+
+  If you type a self-inserting character in the range 0240 through
+0377, or if you use @kbd{C-q} to insert one, Emacs assumes you
+intended to use one of the ISO address@hidden character sets, and
+converts it to the Emacs code representing that address@hidden
+character.  You select @emph{which} ISO Latin character set to use
+through your choice of language environment
address@hidden
+(see above).
address@hidden iftex
address@hidden
+(@pxref{Language Environments}).
address@hidden ifnottex
+If you do not specify a choice, the default is Latin-1.
+
+  If you insert a character in the range 0200 through 0237, which
+forms the @code{eight-bit-control} character set, it is inserted
+literally.  You should normally avoid doing this since buffers
+containing such characters have to be written out in either the
address@hidden or @code{raw-text} coding system, which is usually
+not what you want.
+
address@hidden Coding Systems
address@hidden Coding Systems
address@hidden coding systems
+
+  Users of various languages have established many more-or-less standard
+coding systems for representing them.  Emacs does not use these coding
+systems internally; instead, it converts from various coding systems to
+its own system when reading data, and converts the internal coding
+system to other coding systems when writing data.  Conversion is
+possible in reading or writing files, in sending or receiving from the
+terminal, and in exchanging data with subprocesses.
+
+  Emacs assigns a name to each coding system.  Most coding systems are
+used for one language, and the name of the coding system starts with the
+language name.  Some coding systems are used for several languages;
+their names usually start with @samp{iso}.  There are also special
+coding systems @code{no-conversion}, @code{raw-text} and
address@hidden which do not convert printing characters at all.
+
address@hidden international files from DOS/Windows systems
+  A special class of coding systems, collectively known as
address@hidden, is designed to support text encoded by MS-Windows and
+MS-DOS software.  The names of these coding systems are
address@hidden@var{nnnn}}, where @var{nnnn} is a 3- or 4-digit number of the
+codepage.  You can use these encodings just like any other coding
+system; for example, to visit a file encoded in codepage 850, type
address@hidden @key{RET} c cp850 @key{RET} C-x C-f @var{filename}
address@hidden@footnote{
+In the MS-DOS port of Emacs, you need to create a @address@hidden
+coding system with @kbd{M-x codepage-setup}, before you can use it.
address@hidden
address@hidden and MULE,,,emacs-extra,Specialized Emacs Features}.
address@hidden iftex
address@hidden
address@hidden and MULE}.
address@hidden ifnottex
+}.
+
+  In addition to converting various representations of address@hidden
+characters, a coding system can perform end-of-line conversion.  Emacs
+handles three different conventions for how to separate lines in a file:
+newline, carriage-return linefeed, and just carriage-return.
+
address@hidden @kbd
address@hidden C-h C @var{coding} @key{RET}
+Describe coding system @var{coding}.
+
address@hidden C-h C @key{RET}
+Describe the coding systems currently in use.
+
address@hidden M-x list-coding-systems
+Display a list of all the supported coding systems.
address@hidden table
+
address@hidden C-h C
address@hidden describe-coding-system
+  The command @kbd{C-h C} (@code{describe-coding-system}) displays
+information about particular coding systems, including the end-of-line
+conversion specified by those coding systems.  You can specify a coding
+system name as the argument; alternatively, with an empty argument, it
+describes the coding systems currently selected for various purposes,
+both in the current buffer and as the defaults, and the priority list
+for recognizing coding systems (@pxref{Recognize Coding}).
+
address@hidden list-coding-systems
+  To display a list of all the supported coding systems, type @kbd{M-x
+list-coding-systems}.  The list gives information about each coding
+system, including the letter that stands for it in the mode line
+(@pxref{Mode Line}).
+
address@hidden end-of-line conversion
address@hidden line endings
address@hidden MS-DOS end-of-line conversion
address@hidden Macintosh end-of-line conversion
+  Each of the coding systems that appear in this list---except for
address@hidden, which means no conversion of any kind---specifies
+how and whether to convert printing characters, but leaves the choice of
+end-of-line conversion to be decided based on the contents of each file.
+For example, if the file appears to use the sequence carriage-return
+linefeed to separate lines, DOS end-of-line conversion will be used.
+
+  Each of the listed coding systems has three variants which specify
+exactly what to do for end-of-line conversion:
+
address@hidden @code
address@hidden @dots{}-unix
+Don't do any end-of-line conversion; assume the file uses
+newline to separate lines.  (This is the convention normally used
+on Unix and GNU systems.)
+
address@hidden @dots{}-dos
+Assume the file uses carriage-return linefeed to separate lines, and do
+the appropriate conversion.  (This is the convention normally used on
+Microsoft address@hidden is also specified for MIME @samp{text/*}
+bodies and in other network transport contexts.  It is different
+from the SGML reference syntax record-start/record-end format which
+Emacs doesn't support directly.})
+
address@hidden @dots{}-mac
+Assume the file uses carriage-return to separate lines, and do the
+appropriate conversion.  (This is the convention normally used on the
+Macintosh system.)
address@hidden table
+
+  These variant coding systems are omitted from the
address@hidden display for brevity, since they are entirely
+predictable.  For example, the coding system @code{iso-latin-1} has
+variants @code{iso-latin-1-unix}, @code{iso-latin-1-dos} and
address@hidden
+
address@hidden @code{undecided}, coding system
+  The coding systems @code{unix}, @code{dos}, and @code{mac} are
+aliases for @code{undecided-unix}, @code{undecided-dos}, and
address@hidden, respectively.  These coding systems specify only
+the end-of-line conversion, and leave the character code conversion to
+be deduced from the text itself.
+
+  The coding system @code{raw-text} is good for a file which is mainly
address@hidden text, but may contain byte values above 127 which are
+not meant to encode address@hidden characters.  With
address@hidden, Emacs copies those byte values unchanged, and sets
address@hidden to @code{nil} in the current buffer
+so that they will be interpreted properly.  @code{raw-text} handles
+end-of-line conversion in the usual way, based on the data
+encountered, and has the usual three variants to specify the kind of
+end-of-line conversion to use.
+
+  In contrast, the coding system @code{no-conversion} specifies no
+character code conversion at all---none for address@hidden byte values and
+none for end of line.  This is useful for reading or writing binary
+files, tar files, and other files that must be examined verbatim.  It,
+too, sets @code{enable-multibyte-characters} to @code{nil}.
+
+  The easiest way to edit a file with no conversion of any kind is with
+the @kbd{M-x find-file-literally} command.  This uses
address@hidden, and also suppresses other Emacs features that
+might convert the file contents before you see them.  @xref{Visiting}.
+
+  The coding system @code{emacs-mule} means that the file contains
address@hidden characters stored with the internal Emacs encoding.  It
+handles end-of-line conversion based on the data encountered, and has
+the usual three variants to specify the kind of end-of-line conversion.
+
address@hidden unify-8859-on-decoding-mode
address@hidden Translation} 
+  The @dfn{character translation} feature can modify the effect of
+various coding systems, by changing the internal Emacs codes that
+decoding produces.  For instance, the command
address@hidden enables a mode that ``unifies'' the
+Latin alphabets when decoding text.  This works by converting all
address@hidden address@hidden characters to either Latin-1 or
+Unicode characters.  This way it is easier to use various
address@hidden alphabets together.  (In a future Emacs version we hope
+to move towards full Unicode support and complete unification of
+character sets.)
+
address@hidden enable-character-translation
+  If you set the variable @code{enable-character-translation} to
address@hidden, that disables all character translation (including
address@hidden).
+
address@hidden Recognize Coding
address@hidden Recognizing Coding Systems
+
+  Emacs tries to recognize which coding system to use for a given text
+as an integral part of reading that text.  (This applies to files
+being read, output from subprocesses, text from X selections, etc.)
+Emacs can select the right coding system automatically most of the
+time---once you have specified your preferences.
+
+  Some coding systems can be recognized or distinguished by which byte
+sequences appear in the data.  However, there are coding systems that
+cannot be distinguished, not even potentially.  For example, there is no
+way to distinguish between Latin-1 and Latin-2; they use the same byte
+values with different meanings.
+
+  Emacs handles this situation by means of a priority list of coding
+systems.  Whenever Emacs reads a file, if you do not specify the coding
+system to use, Emacs checks the data against each coding system,
+starting with the first in priority and working down the list, until it
+finds a coding system that fits the data.  Then it converts the file
+contents assuming that they are represented in this coding system.
+
+  The priority list of coding systems depends on the selected language
+environment (@pxref{Language Environments}).  For example, if you use
+French, you probably want Emacs to prefer Latin-1 to Latin-2; if you use
+Czech, you probably want Latin-2 to be preferred.  This is one of the
+reasons to specify a language environment.
+
address@hidden prefer-coding-system
+  However, you can alter the coding system priority list in detail
+with the command @kbd{M-x prefer-coding-system}.  This command reads
+the name of a coding system from the minibuffer, and adds it to the
+front of the priority list, so that it is preferred to all others.  If
+you use this command several times, each use adds one element to the
+front of the priority list.
+
+  If you use a coding system that specifies the end-of-line conversion
+type, such as @code{iso-8859-1-dos}, what this means is that Emacs
+should attempt to recognize @code{iso-8859-1} with priority, and should
+use DOS end-of-line conversion when it does recognize @code{iso-8859-1}.
+
address@hidden file-coding-system-alist
+  Sometimes a file name indicates which coding system to use for the
+file.  The variable @code{file-coding-system-alist} specifies this
+correspondence.  There is a special function
address@hidden for adding elements to this list.  For
+example, to read and write all @samp{.txt} files using the coding system
address@hidden, you can execute this Lisp expression:
+
address@hidden
+(modify-coding-system-alist 'file "\\.txt\\'" 'chinese-iso-8bit)
address@hidden smallexample
+
address@hidden
+The first argument should be @code{file}, the second argument should be
+a regular expression that determines which files this applies to, and
+the third argument says which coding system to use for these files.
+
address@hidden inhibit-eol-conversion
address@hidden DOS-style end-of-line display
+  Emacs recognizes which kind of end-of-line conversion to use based on
+the contents of the file: if it sees only carriage-returns, or only
+carriage-return linefeed sequences, then it chooses the end-of-line
+conversion accordingly.  You can inhibit the automatic use of
+end-of-line conversion by setting the variable @code{inhibit-eol-conversion}
+to address@hidden  If you do that, DOS-style files will be displayed
+with the @samp{^M} characters visible in the buffer; some people
+prefer this to the more subtle @samp{(DOS)} end-of-line type
+indication near the left edge of the mode line (@pxref{Mode Line,
+eol-mnemonic}).
+
address@hidden inhibit-iso-escape-detection
address@hidden escape sequences in files
+  By default, the automatic detection of coding system is sensitive to
+escape sequences.  If Emacs sees a sequence of characters that begin
+with an escape character, and the sequence is valid as an ISO-2022
+code, that tells Emacs to use one of the ISO-2022 encodings to decode
+the file.
+
+  However, there may be cases that you want to read escape sequences
+in a file as is.  In such a case, you can set the variable
address@hidden to address@hidden  Then the code
+detection ignores any escape sequences, and never uses an ISO-2022
+encoding.  The result is that all escape sequences become visible in
+the buffer.
+
+  The default value of @code{inhibit-iso-escape-detection} is
address@hidden  We recommend that you not change it permanently, only for
+one specific operation.  That's because many Emacs Lisp source files
+in the Emacs distribution contain address@hidden characters encoded in the
+coding system @code{iso-2022-7bit}, and they won't be
+decoded correctly when you visit those files if you suppress the
+escape sequence detection.
+
address@hidden auto-coding-alist
address@hidden auto-coding-regexp-alist
address@hidden auto-coding-functions
+  The variables @code{auto-coding-alist},
address@hidden and @code{auto-coding-functions} are
+the strongest way to specify the coding system for certain patterns of
+file names, or for files containing certain patterns; these variables
+even override @samp{-*-coding:-*-} tags in the file itself.  Emacs
+uses @code{auto-coding-alist} for tar and archive files, to prevent it
+from being confused by a @samp{-*-coding:-*-} tag in a member of the
+archive and thinking it applies to the archive file as a whole.
+Likewise, Emacs uses @code{auto-coding-regexp-alist} to ensure that
+RMAIL files, whose names in general don't match any particular
+pattern, are decoded correctly.  One of the builtin
address@hidden detects the encoding for XML files.
+
address@hidden rmail-decode-mime-charset
+  When you get new mail in Rmail, each message is translated
+automatically from the coding system it is written in, as if it were a
+separate file.  This uses the priority list of coding systems that you
+have specified.  If a MIME message specifies a character set, Rmail
+obeys that specification, unless @code{rmail-decode-mime-charset} is
address@hidden
+
address@hidden rmail-file-coding-system
+  For reading and saving Rmail files themselves, Emacs uses the coding
+system specified by the variable @code{rmail-file-coding-system}.  The
+default value is @code{nil}, which means that Rmail files are not
+translated (they are read and written in the Emacs internal character
+code).
+
address@hidden Specify Coding
address@hidden Specifying a File's Coding System
+
+  If Emacs recognizes the encoding of a file incorrectly, you can
+reread the file using the correct coding system by typing @kbd{C-x
address@hidden r @var{coding-system} @key{RET}}.  To see what coding system
+Emacs actually used to decode the file, look at the coding system
+mnemonic letter near the left edge of the mode line (@pxref{Mode
+Line}), or type @kbd{C-h C @key{RET}}.
+
address@hidden coding
+  You can specify the coding system for a particular file in the file
+itself, using the @address@hidden@dots{}-*-}} construct at the beginning,
+or a local variables list at the end (@pxref{File Variables}).  You do
+this by defining a value for the ``variable'' named @code{coding}.
+Emacs does not really have a variable @code{coding}; instead of
+setting a variable, this uses the specified coding system for the
+file.  For example, @samp{-*-mode: C; coding: latin-1;-*-} specifies
+use of the Latin-1 coding system, as well as C mode.  When you specify
+the coding explicitly in the file, that overrides
address@hidden
+
+  If you add the character @samp{!} at the end of the coding system
+name in @code{coding}, it disables any character translation
+(@pxref{Character Translation}) while decoding the file.  This is
+useful when you need to make sure that the character codes in the
+Emacs buffer will not vary due to changes in user settings; for
+instance, for the sake of strings in Emacs Lisp source files.
+
address@hidden Output Coding
address@hidden Choosing Coding Systems for Output
+
address@hidden buffer-file-coding-system
+  Once Emacs has chosen a coding system for a buffer, it stores that
+coding system in @code{buffer-file-coding-system}.  That makes it the
+default for operations that write from this buffer into a file, such
+as @code{save-buffer} and @code{write-region}.  You can specify a
+different coding system for further file output from the buffer using
address@hidden (@pxref{Text Coding}).
+
+  You can insert any character Emacs supports into any Emacs buffer,
+but most coding systems can only handle a subset of these characters.
+Therefore, you can insert characters that cannot be encoded with the
+coding system that will be used to save the buffer.  For example, you
+could start with an @acronym{ASCII} file and insert a few Latin-1
+characters into it, or you could edit a text file in Polish encoded in
address@hidden and add some Russian words to it.  When you save
+that buffer, Emacs cannot use the current value of
address@hidden, because the characters you added
+cannot be encoded by that coding system.
+
+  When that happens, Emacs tries the most-preferred coding system (set
+by @kbd{M-x prefer-coding-system} or @kbd{M-x
+set-language-environment}), and if that coding system can safely
+encode all of the characters in the buffer, Emacs uses it, and stores
+its value in @code{buffer-file-coding-system}.  Otherwise, Emacs
+displays a list of coding systems suitable for encoding the buffer's
+contents, and asks you to choose one of those coding systems.
+
+  If you insert the unsuitable characters in a mail message, Emacs
+behaves a bit differently.  It additionally checks whether the
+most-preferred coding system is recommended for use in MIME messages;
+if not, Emacs tells you that the most-preferred coding system is not
+recommended and prompts you for another coding system.  This is so you
+won't inadvertently send a message encoded in a way that your
+recipient's mail software will have difficulty decoding.  (You can
+still use an unsuitable coding system if you type its name in response
+to the question.)
+
address@hidden sendmail-coding-system
+  When you send a message with Mail mode (@pxref{Sending Mail}), Emacs has
+four different ways to determine the coding system to use for encoding
+the message text.  It tries the buffer's own value of
address@hidden, if that is address@hidden  Otherwise,
+it uses the value of @code{sendmail-coding-system}, if that is
address@hidden  The third way is to use the default coding system for
+new files, which is controlled by your choice of language environment,
+if that is address@hidden  If all of these three values are @code{nil},
+Emacs encodes outgoing mail using the Latin-1 coding system.
+
address@hidden Text Coding
address@hidden Specifying a Coding System for File Text
+
+  In cases where Emacs does not automatically choose the right coding
+system for a file's contents, you can use these commands to specify
+one:
+
address@hidden @kbd
address@hidden C-x @key{RET} f @var{coding} @key{RET}
+Use coding system @var{coding} for saving or revisiting the visited
+file in the current buffer.
+
address@hidden C-x @key{RET} c @var{coding} @key{RET}
+Specify coding system @var{coding} for the immediately following
+command.
+
address@hidden C-x @key{RET} r @var{coding} @key{RET}
+Revisit the current file using the coding system @var{coding}.
+
address@hidden M-x recode-region @key{RET} @var{right} @key{RET} @var{wrong} 
@key{RET}
+Convert a region that was decoded using coding system @var{wrong},
+decoding it using coding system @var{right} instead.
address@hidden table
+
address@hidden C-x RET f
address@hidden set-buffer-file-coding-system
+  The command @kbd{C-x @key{RET} f}
+(@code{set-buffer-file-coding-system}) sets the file coding system for
+the current buffer---in other words, it says which coding system to
+use when saving or reverting the visited file.  You specify which
+coding system using the minibuffer.  If you specify a coding system
+that cannot handle all of the characters in the buffer, Emacs warns
+you about the troublesome characters when you actually save the
+buffer.
+
address@hidden specify end-of-line conversion
+  You can also use this command to specify the end-of-line conversion
+(@pxref{Coding Systems, end-of-line conversion}) for encoding the
+current buffer.  For example, @kbd{C-x @key{RET} f dos @key{RET}} will
+cause Emacs to save the current buffer's text with DOS-style CRLF line
+endings.
+
address@hidden C-x RET c
address@hidden universal-coding-system-argument
+  Another way to specify the coding system for a file is when you visit
+the file.  First use the command @kbd{C-x @key{RET} c}
+(@code{universal-coding-system-argument}); this command uses the
+minibuffer to read a coding system name.  After you exit the minibuffer,
+the specified coding system is used for @emph{the immediately following
+command}.
+
+  So if the immediately following command is @kbd{C-x C-f}, for example,
+it reads the file using that coding system (and records the coding
+system for when you later save the file).  Or if the immediately following
+command is @kbd{C-x C-w}, it writes the file using that coding system.
+When you specify the coding system for saving in this way, instead
+of with @kbd{C-x @key{RET} f}, there is no warning if the buffer
+contains characters that the coding system cannot handle.
+
+  Other file commands affected by a specified coding system include
address@hidden i} and @kbd{C-x C-v}, as well as the other-window variants
+of @kbd{C-x C-f}.  @kbd{C-x @key{RET} c} also affects commands that
+start subprocesses, including @kbd{M-x shell} (@pxref{Shell}).  If the
+immediately following command does not use the coding system, then
address@hidden @key{RET} c} ultimately has no effect.
+
+  An easy way to visit a file with no conversion is with the @kbd{M-x
+find-file-literally} command.  @xref{Visiting}.
+
address@hidden default-buffer-file-coding-system
+  The variable @code{default-buffer-file-coding-system} specifies the
+choice of coding system to use when you create a new file.  It applies
+when you find a new file, and when you create a buffer and then save it
+in a file.  Selecting a language environment typically sets this
+variable to a good choice of default coding system for that language
+environment.
+
address@hidden C-x RET r
address@hidden revert-buffer-with-coding-system
+  If you visit a file with a wrong coding system, you can correct this
+with @kbd{C-x @key{RET} r} (@code{revert-buffer-with-coding-system}).
+This visits the current file again, using a coding system you specify.
+
address@hidden recode-region
+  If a piece of text has already been inserted into a buffer using the
+wrong coding system, you can redo the decoding of it using @kbd{M-x
+recode-region}.  This prompts you for the proper coding system, then
+for the wrong coding system that was actually used, and does the
+conversion.  It first encodes the region using the wrong coding system,
+then decodes it again using the proper coding system.
+
address@hidden Communication Coding
address@hidden Coding Systems for Interprocess Communication
+
+  This section explains how to specify coding systems for use
+in communication with other processes.
+
address@hidden @kbd
address@hidden C-x @key{RET} x @var{coding} @key{RET}
+Use coding system @var{coding} for transferring selections to and from
+other window-based applications.
+
address@hidden C-x @key{RET} X @var{coding} @key{RET}
+Use coding system @var{coding} for transferring @emph{one}
+selection---the next one---to or from another window-based application.
+
address@hidden C-x @key{RET} p @var{input-coding} @key{RET} @var{output-coding} 
@key{RET}
+Use coding systems @var{input-coding} and @var{output-coding} for
+subprocess input and output in the current buffer.
+
address@hidden C-x @key{RET} c @var{coding} @key{RET}
+Specify coding system @var{coding} for the immediately following
+command.
address@hidden table
+
address@hidden C-x RET x
address@hidden C-x RET X
address@hidden set-selection-coding-system
address@hidden set-next-selection-coding-system
+  The command @kbd{C-x @key{RET} x} (@code{set-selection-coding-system})
+specifies the coding system for sending selected text to other windowing
+applications, and for receiving the text of selections made in other
+applications.  This command applies to all subsequent selections, until
+you override it by using the command again.  The command @kbd{C-x
address@hidden X} (@code{set-next-selection-coding-system}) specifies the
+coding system for the next selection made in Emacs or read by Emacs.
+
address@hidden C-x RET p
address@hidden set-buffer-process-coding-system
+  The command @kbd{C-x @key{RET} p} (@code{set-buffer-process-coding-system})
+specifies the coding system for input and output to a subprocess.  This
+command applies to the current buffer; normally, each subprocess has its
+own buffer, and thus you can use this command to specify translation to
+and from a particular subprocess by giving the command in the
+corresponding buffer.
+
+  You can also use @kbd{C-x @key{RET} c} just before the command that
+runs or starts a subprocess, to specify the coding system to use for
+communication with that subprocess.
+
+  The default for translation of process input and output depends on the
+current language environment.
+
address@hidden locale-coding-system
address@hidden decoding address@hidden keyboard input on X
+  The variable @code{locale-coding-system} specifies a coding system
+to use when encoding and decoding system strings such as system error
+messages and @code{format-time-string} formats and time stamps.  That
+coding system is also used for decoding address@hidden keyboard input on X
+Window systems.  You should choose a coding system that is compatible
+with the underlying system's text representation, which is normally
+specified by one of the environment variables @env{LC_ALL},
address@hidden, and @env{LANG}.  (The first one, in the order
+specified above, whose value is nonempty is the one that determines
+the text representation.)
+
address@hidden File Name Coding
address@hidden Coding Systems for File Names
+
address@hidden @kbd
address@hidden C-x @key{RET} F @var{coding} @key{RET}
+Use coding system @var{coding} for encoding and decoding file
address@hidden
address@hidden table
+
address@hidden file-name-coding-system
address@hidden file names with address@hidden characters
+  The variable @code{file-name-coding-system} specifies a coding
+system to use for encoding file names.  It has no effect on reading
+and writing the @emph{contents} of files.
+
address@hidden set-file-name-coding-system
address@hidden C-x @key{RET} F
+  If you set the variable to a coding system name (as a Lisp symbol or
+a string), Emacs encodes file names using that coding system for all
+file operations.  This makes it possible to use address@hidden
+characters in file names---or, at least, those address@hidden
+characters which the specified coding system can encode.  Use @kbd{C-x
address@hidden F} (@code{set-file-name-coding-system}) to specify this
+interactively.
+
+  If @code{file-name-coding-system} is @code{nil}, Emacs uses a
+default coding system determined by the selected language environment.
+In the default language environment, any address@hidden
+characters in file names are not encoded specially; they appear in the
+file system using the internal Emacs representation.
+
+  @strong{Warning:} if you change @code{file-name-coding-system} (or the
+language environment) in the middle of an Emacs session, problems can
+result if you have already visited files whose names were encoded using
+the earlier coding system and cannot be encoded (or are encoded
+differently) under the new coding system.  If you try to save one of
+these buffers under the visited file name, saving may use the wrong file
+name, or it may get an error.  If such a problem happens, use @kbd{C-x
+C-w} to specify a new file name for that buffer.
+
address@hidden recode-file-name
+  If a mistake occurs when encoding a file name, use the command
address@hidden recode-file-name} to change the file name's coding
+system.  This prompts for an existing file name, its old coding
+system, and the coding system to which you wish to convert.
+
address@hidden Terminal Coding
address@hidden Coding Systems for Terminal I/O
+
address@hidden @kbd
address@hidden C-x @key{RET} k @var{coding} @key{RET}
+Use coding system @var{coding} for keyboard input.
+
address@hidden C-x @key{RET} t @var{coding} @key{RET}
+Use coding system @var{coding} for terminal output.
address@hidden table
+
address@hidden C-x RET t
address@hidden set-terminal-coding-system
+  The command @kbd{C-x @key{RET} t} (@code{set-terminal-coding-system})
+specifies the coding system for terminal output.  If you specify a
+character code for terminal output, all characters output to the
+terminal are translated into that coding system.
+
+  This feature is useful for certain character-only terminals built to
+support specific languages or character sets---for example, European
+terminals that support one of the ISO Latin character sets.  You need to
+specify the terminal coding system when using multibyte text, so that
+Emacs knows which characters the terminal can actually handle.
+
+  By default, output to the terminal is not translated at all, unless
+Emacs can deduce the proper coding system from your terminal type or
+your locale specification (@pxref{Language Environments}).
+
address@hidden C-x RET k
address@hidden set-keyboard-coding-system
address@hidden keyboard-coding-system
+  The command @kbd{C-x @key{RET} k} (@code{set-keyboard-coding-system})
+or the variable @code{keyboard-coding-system} specifies the coding
+system for keyboard input.  Character-code translation of keyboard
+input is useful for terminals with keys that send address@hidden
+graphic characters---for example, some terminals designed for ISO
+Latin-1 or subsets of it.
+
+  By default, keyboard input is translated based on your system locale
+setting.  If your terminal does not really support the encoding
+implied by your locale (for example, if you find it inserts a
address@hidden character if you type @kbd{M-i}), you will need to set
address@hidden to @code{nil} to turn off encoding.
+You can do this by putting
+
address@hidden
+(set-keyboard-coding-system nil)
address@hidden lisp
+
address@hidden
+in your @file{~/.emacs} file.
+
+  There is a similarity between using a coding system translation for
+keyboard input, and using an input method: both define sequences of
+keyboard input that translate into single characters.  However, input
+methods are designed to be convenient for interactive use by humans, and
+the sequences that are translated are typically sequences of @acronym{ASCII}
+printing characters.  Coding systems typically translate sequences of
+non-graphic characters.
+
address@hidden Fontsets
address@hidden Fontsets
address@hidden fontsets
+
+  A font typically defines shapes for a single alphabet or script.
+Therefore, displaying the entire range of scripts that Emacs supports
+requires a collection of many fonts.  In Emacs, such a collection is
+called a @dfn{fontset}.  A fontset is defined by a list of fonts, each
+assigned to handle a range of character codes.
+
+  Each fontset has a name, like a font.  However, while fonts are
+stored in the system and the available font names are defined by the
+system, fontsets are defined within Emacs itself.  Once you have
+defined a fontset, you can use it within Emacs by specifying its name,
+anywhere that you could use a single font.  Of course, Emacs fontsets
+can use only the fonts that the system supports; if certain characters
+appear on the screen as hollow boxes, this means that the fontset in
+use for them has no font for those address@hidden Emacs
+installation instructions have information on additional font
+support.}
+
+  Emacs creates two fontsets automatically: the @dfn{standard fontset}
+and the @dfn{startup fontset}.  The standard fontset is most likely to
+have fonts for a wide variety of address@hidden characters;
+however, this is not the default for Emacs to use.  (By default, Emacs
+tries to find a font that has bold and italic variants.)  You can
+specify use of the standard fontset with the @samp{-fn} option.  For
+example,
+
address@hidden
+emacs -fn fontset-standard
address@hidden example
+
address@hidden
+You can also specify a fontset with the @samp{Font} resource (@pxref{X
+Resources}).
+
+  A fontset does not necessarily specify a font for every character
+code.  If a fontset specifies no font for a certain character, or if it
+specifies a font that does not exist on your system, then it cannot
+display that character properly.  It will display that character as an
+empty box instead.
+
address@hidden Defining Fontsets
address@hidden Defining fontsets
+
address@hidden standard-fontset-spec
address@hidden standard fontset
+  Emacs creates a standard fontset automatically according to the value
+of @code{standard-fontset-spec}.  This fontset's name is
+
address@hidden
+-*-fixed-medium-r-normal-*-16-*-*-*-*-*-fontset-standard
address@hidden example
+
address@hidden
+or just @samp{fontset-standard} for short.
+
+  Bold, italic, and bold-italic variants of the standard fontset are
+created automatically.  Their names have @samp{bold} instead of
address@hidden, or @samp{i} instead of @samp{r}, or both.
+
address@hidden startup fontset
+  If you specify a default @acronym{ASCII} font with the @samp{Font} resource 
or
+the @samp{-fn} argument, Emacs generates a fontset from it
+automatically.  This is the @dfn{startup fontset} and its name is
address@hidden  It does this by replacing the @var{foundry},
address@hidden, @var{add_style}, and @var{average_width} fields of the
+font name with @samp{*}, replacing @var{charset_registry} field with
address@hidden, and replacing @var{charset_encoding} field with
address@hidden, then using the resulting string to specify a fontset.
+
+  For instance, if you start Emacs this way,
+
address@hidden
+emacs -fn "*courier-medium-r-normal--14-140-*-iso8859-1"
address@hidden example
+
address@hidden
+Emacs generates the following fontset and uses it for the initial X
+window frame:
+
address@hidden
+-*-*-medium-r-normal-*-14-140-*-*-*-*-fontset-startup
address@hidden example
+
+  With the X resource @samp{Emacs.Font}, you can specify a fontset name
+just like an actual font name.  But be careful not to specify a fontset
+name in a wildcard resource like @samp{Emacs*Font}---that wildcard
+specification matches various other resources, such as for menus, and
+menus cannot handle fontsets.
+
+  You can specify additional fontsets using X resources named
address@hidden@var{n}}, where @var{n} is an integer starting from 0.
+The resource value should have this form:
+
address@hidden
address@hidden, @address@hidden:@address@hidden@dots{}}
address@hidden smallexample
+
address@hidden
address@hidden should have the form of a standard X font name, except
+for the last two fields.  They should have the form
address@hidden@var{alias}}.
+
+  The fontset has two names, one long and one short.  The long name is
address@hidden  The short name is @address@hidden  You
+can refer to the fontset by either name.
+
+  The construct @address@hidden:@var{font}} specifies which font to
+use (in this fontset) for one particular character set.  Here,
address@hidden is the name of a character set, and @var{font} is the
+font to use for that character set.  You can use this construct any
+number of times in defining one fontset.
+
+  For the other character sets, Emacs chooses a font based on
address@hidden  It replaces @address@hidden with values
+that describe the character set.  For the @acronym{ASCII} character font,
address@hidden@var{alias}} is replaced with @samp{ISO8859-1}.
+
+  In addition, when several consecutive fields are wildcards, Emacs
+collapses them into a single wildcard.  This is to prevent use of
+auto-scaled fonts.  Fonts made by scaling larger fonts are not usable
+for editing, and scaling a smaller font is not useful because it is
+better to use the smaller font in its own size, which is what Emacs
+does.
+
+  Thus if @var{fontpattern} is this,
+
address@hidden
+-*-fixed-medium-r-normal-*-24-*-*-*-*-*-fontset-24
address@hidden example
+
address@hidden
+the font specification for @acronym{ASCII} characters would be this:
+
address@hidden
+-*-fixed-medium-r-normal-*-24-*-ISO8859-1
address@hidden example
+
address@hidden
+and the font specification for Chinese GB2312 characters would be this:
+
address@hidden
+-*-fixed-medium-r-normal-*-24-*-gb2312*-*
address@hidden example
+
+  You may not have any Chinese font matching the above font
+specification.  Most X distributions include only Chinese fonts that
+have @samp{song ti} or @samp{fangsong ti} in @var{family} field.  In
+such a case, @address@hidden can be specified as below:
+
address@hidden
+Emacs.Fontset-0: -*-fixed-medium-r-normal-*-24-*-*-*-*-*-fontset-24,\
+        chinese-gb2312:-*-*-medium-r-normal-*-24-*-gb2312*-*
address@hidden smallexample
+
address@hidden
+Then, the font specifications for all but Chinese GB2312 characters have
address@hidden in the @var{family} field, and the font specification for
+Chinese GB2312 characters has a wild card @samp{*} in the @var{family}
+field.
+
address@hidden create-fontset-from-fontset-spec
+  The function that processes the fontset resource value to create the
+fontset is called @code{create-fontset-from-fontset-spec}.  You can also
+call this function explicitly to create a fontset.
+
+  @xref{Font X}, for more information about font naming in X.
+
address@hidden Undisplayable Characters
address@hidden Undisplayable Characters
+
+  There may be a some address@hidden characters that your terminal cannot
+display.  Most text-only terminals support just a single character
+set (use the variable @code{default-terminal-coding-system}
+(@pxref{Terminal Coding}) to tell Emacs which one); characters which
+can't be encoded in that coding system are displayed as @samp{?} by
+default.
+
+  Graphical displays can display a broader range of characters, but
+you may not have fonts installed for all of them; characters that have
+no font appear as a hollow box.
+
+  If you use Latin-1 characters but your terminal can't display
+Latin-1, you can arrange to display mnemonic @acronym{ASCII} sequences
+instead, e.g.@: @samp{"o} for o-umlaut.  Load the library
address@hidden to do this.
+
address@hidden latin1-display
+  If your terminal can display Latin-1, you can display characters
+from other European character sets using a mixture of equivalent
+Latin-1 characters and @acronym{ASCII} mnemonics.  Customize the variable
address@hidden to enable this.  The mnemonic @acronym{ASCII}
+sequences mostly correspond to those of the prefix input methods.
+
address@hidden Unibyte Mode
address@hidden Unibyte Editing Mode
+
address@hidden European character sets
address@hidden accented characters
address@hidden ISO Latin character sets
address@hidden Unibyte operation
+  The ISO 8859 address@hidden character sets define character codes in
+the range 0240 to 0377 octal (160 to 255 decimal) to handle the
+accented letters and punctuation needed by various European languages
+(and some non-European ones).  If you disable multibyte characters,
+Emacs can still handle @emph{one} of these character codes at a time.
+To specify @emph{which} of these codes to use, invoke @kbd{M-x
+set-language-environment} and specify a suitable language environment
+such as @address@hidden
+
+  For more information about unibyte operation, see @ref{Enabling
+Multibyte}.  Note particularly that you probably want to ensure that
+your initialization files are read as unibyte if they contain
address@hidden characters.
+
address@hidden unibyte-display-via-language-environment
+  Emacs can also display those characters, provided the terminal or font
+in use supports them.  This works automatically.  Alternatively, on a
+graphical display, Emacs can also display single-byte characters
+through fontsets, in effect by displaying the equivalent multibyte
+characters according to the current language environment.  To request
+this, set the variable @code{unibyte-display-via-language-environment}
+to a address@hidden value.
+
address@hidden @code{iso-ascii} library
+  If your terminal does not support display of the Latin-1 character
+set, Emacs can display these characters as @acronym{ASCII} sequences which at
+least give you a clear idea of what the characters are.  To do this,
+load the library @code{iso-ascii}.  Similar libraries for other
address@hidden character sets could be implemented, but we don't have
+them yet.
+
address@hidden standard-display-8bit
address@hidden 8-bit display
+  Normally non-ISO-8859 characters (decimal codes between 128 and 159
+inclusive) are displayed as octal escapes.  You can change this for
+non-standard ``extended'' versions of ISO-8859 character sets by using the
+function @code{standard-display-8bit} in the @code{disp-table} library.
+
+  There are two ways to input single-byte address@hidden
+characters:
+
address@hidden @bullet
address@hidden 8-bit input
address@hidden
+You can use an input method for the selected language environment.
address@hidden Methods}.  When you use an input method in a unibyte buffer,
+the address@hidden character you specify with it is converted to unibyte.
+
address@hidden
+If your keyboard can generate character codes 128 (decimal) and up,
+representing address@hidden characters, you can type those character codes
+directly.
+
+On a graphical display, you should not need to do anything special to use
+these keys; they should simply work.  On a text-only terminal, you
+should use the command @code{M-x set-keyboard-coding-system} or the
+variable @code{keyboard-coding-system} to specify which coding system
+your keyboard uses (@pxref{Terminal Coding}).  Enabling this feature
+will probably require you to use @kbd{ESC} to type Meta characters;
+however, on a console terminal or in @code{xterm}, you can arrange for
+Meta to be converted to @kbd{ESC} and still be able type 8-bit
+characters present directly on the keyboard or using @kbd{Compose} or
address@hidden keys.  @xref{User Input}.
+
address@hidden C-x 8
address@hidden @code{iso-transl} library
address@hidden compose character
address@hidden dead character
address@hidden
+For Latin-1 only, you can use the key @kbd{C-x 8} as a ``compose
+character'' prefix for entry of address@hidden Latin-1 printing
+characters.  @kbd{C-x 8} is good for insertion (in the minibuffer as
+well as other buffers), for searching, and in any other context where
+a key sequence is allowed.
+
address@hidden 8} works by loading the @code{iso-transl} library.  Once that
+library is loaded, the @key{ALT} modifier key, if the keyboard has
+one, serves the same purpose as @kbd{C-x 8}: use @key{ALT} together
+with an accent character to modify the following letter.  In addition,
+if the keyboard has keys for the Latin-1 ``dead accent characters,''
+they too are defined to compose with the following character, once
address@hidden is loaded.
+
+Use @kbd{C-x 8 C-h} to list all the available @kbd{C-x 8} translations.
address@hidden itemize
+
address@hidden Charsets
address@hidden Charsets
address@hidden charsets
+
+  Emacs groups all supported characters into disjoint @dfn{charsets}.
+Each character code belongs to one and only one charset.  For
+historical reasons, Emacs typically divides an 8-bit character code
+for an extended version of @acronym{ASCII} into two charsets:
address@hidden, which covers the codes 0 through 127, plus another
+charset which covers the ``right-hand part'' (the codes 128 and up).
+For instance, the characters of Latin-1 include the Emacs charset
address@hidden plus the Emacs charset @code{latin-iso8859-1}.
+
+  Emacs characters belonging to different charsets may look the same,
+but they are still different characters.  For example, the letter
address@hidden with acute accent in charset @code{latin-iso8859-1}, used for
+Latin-1, is different from the letter @samp{o} with acute accent in
+charset @code{latin-iso8859-2}, used for Latin-2.
+
address@hidden list-charset-chars
address@hidden characters in a certain charset
address@hidden describe-character-set
+  There are two commands for obtaining information about Emacs
+charsets.  The command @kbd{M-x list-charset-chars} prompts for a name
+of a character set, and displays all the characters in that character
+set.  The command @kbd{M-x describe-character-set} prompts for a
+charset name and displays information about that charset, including
+its internal representation within Emacs.
+
+  To find out which charset a character in the buffer belongs to,
+put point before it and type @kbd{C-u C-x =}.
+
address@hidden
+   arch-tag: 310ba60d-31ef-4ce7-91f1-f282dd57b6b3
address@hidden ignore