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ext::Encode::lib:PerloProgreaxmtm:e:rEsncRoedfee:r:lib::Encode::Supported(3p)


NAME
       Encode::Supported -- Encodings supported by Encode

DESCRIPTION
       Encoding Names

       Encoding names are case insensitive. White space in names
       is ignored.  In addition, an encoding may have aliases.
       Each encoding has one "canonical" name.  The "canonical"
       name is chosen from the names of the encoding by picking
       the first in the following sequence (with a few excep-
       tions).

       o   The name used by the Perl community.  That includes
           'utf8' and 'ascii'.  Unlike aliases, canonical names
           directly reach the method so such frequently used
           words like 'utf8' don't need to do alias lookups.

       o   The MIME name as defined in IETF RFCs.  This includes
           all "iso-"s.

       o   The name in the IANA registry.

       o   The name used by the organization that defined it.

       In case de jure canonical names differ from that of the
       Encode module, they are always aliased if it ever be
       implemented.  So you can safely tell if a given encoding
       is implemented or not just by passing the canonical name.

       Because of all the alias issues, and because in the gen-
       eral case encodings have state, "Encode" uses an encoding
       object internally once an operation is in progress.

Supported Encodings
       As of Perl 5.8.0, at least the following encodings are
       recognized.  Note that unless otherwise specified, they
       are all case insensitive (via alias) and all occurrence of
       spaces are replaced with '-'.  In other words, "ISO 8859
       1" and "iso-8859-1" are identical.

       Encodings are categorized and implemented in several dif-
       ferent modules but you don't have to "use Encode::XX" to
       make them available for most cases.  Encode.pm will auto-
       matically load those modules on demand.

       Built-in Encodings

       The following encodings are always available.








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         Canonical     Aliases                      Comments & References
         ----------------------------------------------------------------
         ascii         US-ascii ISO-646-US                         [ECMA]
         ascii-ctrl                                      Special Encoding
         iso-8859-1    latin1                                       [ISO]
         null                                            Special Encoding
         utf8          UTF-8                                    [RFC2279]
         ----------------------------------------------------------------

       null and ascii-ctrl are special.  "null" fails for all
       character so when you set fallback mode to PERLQQ, HTML-
       CREF or XMLCREF, ALL CHARACTERS will fall back to charac-
       ter references.  Ditto for "ascii-ctrl" except for control
       characters.  For fallback modes, see Encode.

       Encode::Unicode -- other Unicode encodings

       Unicode coding schemes other than native utf8 are sup-
       ported by Encode::Unicode, which will be autoloaded on
       demand.

         ----------------------------------------------------------------
         UCS-2BE       UCS-2, iso-10646-1                      [IANA, UC]
         UCS-2LE                                                     [UC]
         UTF-16                                                      [UC]
         UTF-16BE                                                    [UC]
         UTF-16LE                                                    [UC]
         UTF-32                                                      [UC]
         UTF-32BE      UCS-4                                         [UC]
         UTF-32LE                                                    [UC]
         UTF-7                                                  [RFC2152]
         ----------------------------------------------------------------

       To find how (UCS-2|UTF-(16|32))(LE|BE)? differ from one
       another, see Encode::Unicode.

       UTF-7 is a special encoding which "re-encodes" UTF-16BE
       into a 7-bit encoding.  It is implemeneted seperately by
       Encode::Unicode::UTF7.

       Encode::Byte -- Extended ASCII

       Encode::Byte implements most single-byte encodings except
       for Symbols and EBCDIC. The following encodings are based
       on single-byte encodings implemented as extended ASCII.
       Most of them map \x80-\xff (upper half) to non-ASCII char-
       acters.

       ISO-8859 and corresponding vendor mappings
           Since there are so many, they are presented in table
           format with languages and corresponding encoding names
           by vendors.  Note that the table is sorted in order of
           ISO-8859 and the corresponding vendor mappings are
           slightly different from that of ISO.  See



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           <http://czyborra.com/charsets/iso8859.html>; for
           details.

             Lang/Regions  ISO/Other Std.  DOS     Windows Macintosh  Others
             ----------------------------------------------------------------
             N. America    (ASCII)         cp437        AdobeStandardEncoding
                                           cp863 (DOSCanadaF)
             W. Europe     iso-8859-1      cp850   cp1252  MacRoman  nextstep
                                                                    hp-roman8
                                           cp860 (DOSPortuguese)
             Cntrl. Europe iso-8859-2      cp852   cp1250  MacCentralEurRoman
                                                           MacCroatian
                                                           MacRomanian
                                                           MacRumanian
             Latin3[1]     iso-8859-3
             Latin4[2]     iso-8859-4
             Cyrillics     iso-8859-5      cp855   cp1251  MacCyrillic
               (See also next section)     cp866           MacUkrainian
             Arabic        iso-8859-6      cp864   cp1256  MacArabic
                                           cp1006          MacFarsi
             Greek         iso-8859-7      cp737   cp1253  MacGreek
                                           cp869 (DOSGreek2)
             Hebrew        iso-8859-8      cp862   cp1255  MacHebrew
             Turkish       iso-8859-9      cp857   cp1254  MacTurkish
             Nordics       iso-8859-10     cp865
                                           cp861           MacIcelandic
                                                           MacSami
             Thai          iso-8859-11[3]  cp874           MacThai
             (iso-8859-12 is nonexistent. Reserved for Indics?)
             Baltics       iso-8859-13     cp775           cp1257
             Celtics       iso-8859-14
             Latin9 [4]    iso-8859-15
             Latin10       iso-8859-16
             Vietnamese    viscii                  cp1258  MacVietnamese
             ----------------------------------------------------------------

             [1] Esperanto, Maltese, and Turkish. Turkish is now on 8859-9.
             [2] Baltics.  Now on 8859-10, except for Latvian.
             [3] TIS 620 +  Non-Breaking Space (0xA0 / U+00A0)
             [4] Nicknamed Latin0; the Euro sign as well as French and Finnish
                 letters that are missing from 8859-1 were added.

           All cp* are also available as ibm-*, ms-*, and win-
           dows-* .  See also <http://czyborra.com/charsets/code-
           pages.html>.

           Macintosh encodings don't seem to be registered in
           such entities as IANA.  "Canonical" names in Encode
           are based upon Apple's Tech Note 1150.  See
           <http://developer.apple.com/technotes/tn/tn1150.html>;
           for details.

       KOI8 - De Facto Standard for the Cyrillic world
           Though ISO-8859 does have ISO-8859-5, the KOI8 series



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           is far more popular in the Net.   Encode comes with
           the following KOI charsets.  For gory details, see
           <http://czyborra.com/charsets/cyrillic.html>;

             ----------------------------------------------------------------
             koi8-f
             koi8-r cp878                                           [RFC1489]
             koi8-u                                                 [RFC2319]
             ----------------------------------------------------------------

       gsm0338 - Hentai Latin 1
           GSM0338 is for GSM handsets. Though it shares alphanu-
           merals with ASCII, control character ranges and other
           parts are mapped very differently, mainly to store
           Greek characters.  There are also escape sequences
           (starting with 0x1B) to cover e.g. the Euro sign.
           Some special cases like a trailing 0x00 byte or a lone
           0x1B byte are not well-defined and decode() will
           return an empty string for them.  One possible
           workaround is

              $gsm =~ s/\x00\z/\x00\x00/;
              $uni = decode("gsm0338", $gsm);
              $uni .= "\xA0" if $gsm =~ /\x1B\z/;

           Note that the Encode implementation of GSM0338 does
           not implement the reuse of Latin capital letters as
           Greek capital letters (for example, the 0x5A is U+005A
           (LATIN CAPITAL LETTER Z), not U+0396 (GREEK CAPITAL
           LETTER ZETA).

           The GSM0338 is also covered in Encode::Byte even
           though it is not an "extended ASCII" encoding.

       CJK: Chinese, Japanese, Korean (Multibyte)

       Note that Vietnamese is listed above.  Also read "Encoding
       vs Charset" below.  Also note that these are implemented
       in distinct modules by countries, due to the size concerns
       (simplified Chinese is mapped to 'CN', continental China,
       while traditional Chinese is mapped to 'TW', Taiwan).
       Please refer to their respective documentation pages.

       Encode::CN -- Continental China
             Standard      DOS/Win Macintosh                Comment/Reference
             ----------------------------------------------------------------
             euc-cn [1]            MacChineseSimp
             (gbk)         cp936 [2]
             gb12345-raw                      { GB12345 without CES }
             gb2312-raw                       { GB2312  without CES }
             hz
             iso-ir-165
             ----------------------------------------------------------------




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             [1] GB2312 is aliased to this.  See L<Microsoft-related naming mess>
             [2] gbk is aliased to this.  See L<Microsoft-related naming mess>

       Encode::JP -- Japan
             Standard      DOS/Win Macintosh                Comment/Reference
             ----------------------------------------------------------------
             euc-jp
             shiftjis      cp932   macJapanese
             7bit-jis
             iso-2022-jp                                            [RFC1468]
             iso-2022-jp-1                                          [RFC2237]
             jis0201-raw  { JIS X 0201 (roman + halfwidth kana) without CES }
             jis0208-raw  { JIS X 0208 (Kanji + fullwidth kana) without CES }
             jis0212-raw  { JIS X 0212 (Extended Kanji)         without CES }
             ----------------------------------------------------------------

       Encode::KR -- Korea
             Standard      DOS/Win Macintosh                Comment/Reference
             ----------------------------------------------------------------
             euc-kr                MacKorean                        [RFC1557]
                           cp949 [1]
             iso-2022-kr                                            [RFC1557]
             johab                                  [KS X 1001:1998, Annex 3]
             ksc5601-raw                              { KSC5601 without CES }
             ----------------------------------------------------------------

             [1] ks_c_5601-1987, (x-)?windows-949, and uhc are aliased to this.
             See below.

       Encode::TW -- Taiwan
             Standard      DOS/Win Macintosh                Comment/Reference
             ----------------------------------------------------------------
             big5-eten     cp950   MacChineseTrad {big5 aliased to big5-eten}
             big5-hkscs
             ----------------------------------------------------------------

       Encode::HanExtra -- More Chinese via CPAN
           Due to the size concerns, additional Chinese encodings
           below are distributed separately on CPAN, under the
           name Encode::HanExtra.

             Standard      DOS/Win Macintosh                Comment/Reference
             ----------------------------------------------------------------
             big5ext                                   CMEX's Big5e Extension
             big5plus                                  CMEX's Big5+ Extension
             cccii         Chinese Character Code for Information Interchange
             euc-tw                             EUC (Extended Unix Character)
             gb18030                          GBK with Traditional Characters
             ----------------------------------------------------------------

       Encode::JIS2K -- JIS X 0213 encodings via CPAN
           Due to size concerns, additional Japanese encodings
           below are distributed separately on CPAN, under the
           name Encode::JIS2K.



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             Standard      DOS/Win Macintosh                Comment/Reference
             ----------------------------------------------------------------
             euc-jisx0213
             shiftjisx0123
             iso-2022-jp-3
             jis0213-1-raw
             jis0213-2-raw
             ----------------------------------------------------------------

       Miscellaneous encodings


       Encode::EBCDIC
           See perlebcdic for details.

             ----------------------------------------------------------------
             cp37
             cp500
             cp875
             cp1026
             cp1047
             posix-bc
             ----------------------------------------------------------------

       Encode::Symbols
           For symbols  and dingbats.

             ----------------------------------------------------------------
             symbol
             dingbats
             MacDingbats
             AdobeZdingbat
             AdobeSymbol
             ----------------------------------------------------------------

       Encode::MIME::Header
           Strictly speaking, MIME header encoding documented in
           RFC 2047 is more of encapsulation than encoding.  How-
           ever, their support in modern world is imperative so
           they are supported.

             ----------------------------------------------------------------
             MIME-Header                                            [RFC2047]
             MIME-B                                                 [RFC2047]
             MIME-Q                                                 [RFC2047]
             ----------------------------------------------------------------

       Encode::Guess
           This one is not a name of encoding but a utility that
           lets you pick up the most appropriate encoding for a
           data out of given suspects.  See Encode::Guess for
           details.





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Unsupported encodings
       The following encodings are not supported as yet; some
       because they are rarely used, some because of technical
       difficulties.  They may be supported by external modules
       via CPAN in the future, however.

       ISO-2022-JP-2 [RFC1554]
           Not very popular yet.  Needs Unicode Database or
           equivalent to implement encode() (because it includes
           JIS X 0208/0212, KSC5601, and GB2312 simultaneously,
           whose code points in Unicode overlap.  So you need to
           lookup the database to determine to what character set
           a given Unicode character should belong).

       ISO-2022-CN [RFC1922]
           Not very popular.  Needs CNS 11643-1 and -2 which are
           not available in this module.  CNS 11643 is supported
           (via euc-tw) in Encode::HanExtra.  Autrijus Tang may
           add support for this encoding in his module in future.

       Various HP-UX encodings
           The following are unsupported due to the lack of map-
           ping data.

             '8'  - arabic8, greek8, hebrew8, kana8, thai8, and turkish8
             '15' - japanese15, korean15, and roi15

       Cyrillic encoding ISO-IR-111
           Anton Tagunov doubts its usefulness.

       ISO-8859-8-1 [Hebrew]
           None of the Encode team knows Hebrew enough
           (ISO-8859-8, cp1255 and MacHebrew are supported
           because and just because there were mappings available
           at <http://www.unicode.org/>;).  Contributions welcome.

       ISIRI 3342, Iran System, ISIRI 2900 [Farsi]
           Ditto.

       Thai encoding TCVN
           Ditto.

       Vietnamese encodings VPS
           Though Jungshik Shin has reported that Mozilla sup-
           ports this encoding, it was too late before 5.8.0 for
           us to add it.  In the future, it may be available via
           a separate module.  See <http://lxr.mozilla.org/sea-
           monkey/source/intl/uconv/ucvlatin/vps.uf> and
           <http://lxr.mozilla.org/seamon-
           key/source/intl/uconv/ucvlatin/vps.ut> if you are
           interested in helping us.

       Various Mac encodings
           The following are unsupported due to the lack of



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           mapping data.

             MacArmenian,  MacBengali,   MacBurmese,   MacEthiopic
             MacExtArabic, MacGeorgian,  MacKannada,   MacKhmer
             MacLaotian,   MacMalayalam, MacMongolian, MacOriya
             MacSinhalese, MacTamil,     MacTelugu,    MacTibetan
             MacVietnamese

           The rest which are already available are based upon
           the vendor mappings at <http://www.unicode.org/Pub-
           lic/MAPPINGS/VENDORS/APPLE/> .

       (Mac) Indic encodings
           The maps for the following are available at
           <http://www.unicode.org/>; but remain unsupport because
           those encodings need algorithmical approach, currently
           unsupported by enc2xs:

             MacDevanagari
             MacGurmukhi
             MacGujarati

           For details, please see "Unicode mapping issues and
           notes:" at <http://www.unicode.org/Public/MAP-
           PINGS/VENDORS/APPLE/DEVANAGA.TXT> .

           I believe this issue is prevalent not only for Mac
           Indics but also in other Indic encodings, but the
           above were the only Indic encodings maps that I could
           find at <http://www.unicode.org/>; .

Encoding vs. Charset -- terminology
       We are used to using the term (character) encoding and
       character set interchangeably.  But just as confusing the
       terms byte and character is dangerous and the terms should
       be differentiated when needed, we need to differentiate
       encoding and character set.

       To understand that, here is a description of how we make
       computers grok our characters.

       o   First we start with which characters to include.  We
           call this collection of characters character reper-
           toire.

       o   Then we have to give each character a unique ID so
           your computer can tell the difference between 'a' and
           'A'.  This itemized character repertoire is now a
           character set.

       o   If your computer can grow the character set without
           further processing, you can go ahead and use it.  This
           is called a coded character set (CCS) or raw character
           encoding.  ASCII is used this way for most cases.



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       o   But in many cases, especially multi-byte CJK encod-
           ings, you have to tweak a little more.  Your network
           connection may not accept any data with the Most Sig-
           nificant Bit set, and your computer may not be able to
           tell if a given byte is a whole character or just half
           of it.  So you have to encode the character set to use
           it.

           A character encoding scheme (CES) determines how to
           encode a given character set, or a set of multiple
           character sets.  7bit ISO-2022 is an example of a CES.
           You switch between character sets via escape
           sequences.

       Technically, or mathematically, speaking, a character set
       encoded in such a CES that maps character by character may
       form a CCS.  EUC is such an example.  The CES of EUC is as
       follows:

       o   Map ASCII unchanged.

       o   Map such a character set that consists of 94 or 96
           powered by N members by adding 0x80 to each byte.

       o   You can also use 0x8e and 0x8f to indicate that the
           following sequence of characters belongs to yet
           another character set.  To each following byte is
           added the value 0x80.

       By carefully looking at the encoded byte sequence, you can
       find that the byte sequence conforms a unique number.  In
       that sense, EUC is a CCS generated by a CES above from up
       to four CCS (complicated?).  UTF-8 falls into this cate-
       gory.  See "UTF-8" in perlUnicode to find out how UTF-8
       maps Unicode to a byte sequence.

       You may also have found out by now why 7bit ISO-2022 can-
       not comprise a CCS.  If you look at a byte sequence
       \x21\x21, you can't tell if it is two !'s or IDEOGRAPHIC
       SPACE.  EUC maps the latter to \xA1\xA1 so you have no
       trouble differentiating between "!!". and " ".

Encoding Classification (by Anton Tagunov and Dan Kogai)
       This section tries to classify the supported encodings by
       their applicability for information exchange over the
       Internet and to choose the most suitable aliases to name
       them in the context of such communication.

       o   To (en|de)code encodings marked by "(**)", you need
           "Encode::HanExtra", available from CPAN.

       Encoding names





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         US-ASCII    UTF-8    ISO-8859-*  KOI8-R
         Shift_JIS   EUC-JP   ISO-2022-JP ISO-2022-JP-1
         EUC-KR      Big5     GB2312

       are registered with IANA as preferred MIME names and may
       be used over the Internet.

       "Shift_JIS" has been officialized by JIS X 0208:1997.
       "Microsoft-related naming mess" gives details.

       "GB2312" is the IANA name for "EUC-CN".  See
       "Microsoft-related naming mess" for details.

       "GB_2312-80" raw encoding is available as "gb2312-raw"
       with Encode. See Encode::CN for details.

         EUC-CN
         KOI8-U        [RFC2319]

       have not been registered with IANA (as of March 2002) but
       seem to be supported by major web browsers.  The IANA name
       for "EUC-CN" is "GB2312".

         KS_C_5601-1987

       is heavily misused.  See "Microsoft-related naming mess"
       for details.

       "KS_C_5601-1987" raw encoding is available as
       "kcs5601-raw" with Encode. See Encode::KR for details.

         UTF-16 UTF-16BE UTF-16LE

       are IANA-registered "charset"s. See [RFC 2781] for
       details.  Jungshik Shin reports that UTF-16 with a BOM is
       well accepted by MS IE 5/6 and NS 4/6. Beware however that

       o   "UTF-16" support in any software you're going to be
           using/interoperating with has probably been less
           tested then "UTF-8" support

       o   "UTF-8" coded data seamlessly passes traditional com-
           mand piping ("cat", "more", etc.) while "UTF-16" coded
           data is likely to cause confusion (with its zero
           bytes, for example)

       o   it is beyond the power of words to describe the way
           HTML browsers encode non-"ASCII" form data. To get a
           general impression, visit
           <http://ppewww.ph.gla.ac.uk/~flavell/charset/form-i18n.html>;.
           While encoding of form data has stabilized for "UTF-8"
           encoded pages (at least IE 5/6, NS 6, and Opera 6
           behave consistently), be sure to expect fun (and
           cross-browser discrepancies) with "UTF-16" encoded



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           pages!

       The rule of thumb is to use "UTF-8" unless you know what
       you're doing and unless you really benefit from using
       "UTF-16".

         ISO-IR-165    [RFC1345]
         VISCII
         GB 12345
         GB 18030 (**)  (see links bellow)
         EUC-TW   (**)

       are totally valid encodings but not registered at IANA.
       The names under which they are listed here are probably
       the most widely-known names for these encodings and are
       recommended names.

         BIG5PLUS (**)

       is a proprietary name.

       Microsoft-related naming mess

       Microsoft products misuse the following names:

       KS_C_5601-1987
           Microsoft extension to "EUC-KR".

           Proper names: "CP949", "UHC", "x-windows-949" (as used
           by Mozilla).

           See <http://lists.w3.org/Archives/Pub-
           lic/ietf-charsets/2001AprJun/0033.html> for details.

           Encode aliases "KS_C_5601-1987" to "cp949" to reflect
           this common misusage. Raw "KS_C_5601-1987" encoding is
           available as "kcs5601-raw".

           See Encode::KR for details.

       GB2312
           Microsoft extension to "EUC-CN".

           Proper names: "CP936", "GBK".

           "GB2312" has been registered in the "EUC-CN" meaning
           at IANA. This has partially repaired the situation:
           Microsoft's "GB2312" has become a superset of the
           official "GB2312".

           Encode aliases "GB2312" to "euc-cn" in full agreement
           with IANA registration. "cp936" is supported sepa-
           rately.  Raw "GB_2312-80" encoding is available as
           "gb2312-raw".



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           See Encode::CN for details.

       Big5
           Microsoft extension to "Big5".

           Proper name: "CP950".

           Encode separately supports "Big5" and "cp950".

       Shift_JIS
           Microsoft's understanding of "Shift_JIS".

           JIS has not endorsed the full Microsoft standard how-
           ever.  The official "Shift_JIS" includes only JIS X
           0201 and JIS X 0208 character sets, while Microsoft
           has always used "Shift_JIS" to encode a wider charac-
           ter repertoire. See "IANA" registration for "Win-
           dows-31J".

           As a historical predecessor, Microsoft's variant prob-
           ably has more rights for the name, though it may be
           objected that Microsoft shouldn't have used JIS as
           part of the name in the first place.

           Unambiguous name: "CP932". "IANA" name (not used?):
           "Windows-31J".

           Encode separately supports "Shift_JIS" and "cp932".

Glossary
       character repertoire
           A collection of unique characters.  A character set in
           the strictest sense. At this stage, characters are not
           numbered.

       coded character set (CCS)
           A character set that is mapped in a way computers can
           use directly.  Many character encodings, including
           EUC, fall in this category.

       character encoding scheme (CES)
           An algorithm to map a character set to a byte
           sequence.  You don't have to be able to tell which
           character set a given byte sequence belongs.  7-bit
           ISO-2022 is a CES but it cannot be a CCS.  EUC is an
           example of being both a CCS and CES.

       charset (in MIME context)
           has long been used in the meaning of "encoding", CES.

           While the word combination "character set" has lost
           this meaning in MIME context since [RFC 2130], the
           "charset" abbreviation has retained it. This is how
           [RFC 2277] and [RFC 2278] bless "charset":



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            This document uses the term "charset" to mean a set of rules for
            mapping from a sequence of octets to a sequence of characters, such
            as the combination of a coded character set and a character encoding
            scheme; this is also what is used as an identifier in MIME "charset="
            parameters, and registered in the IANA charset registry ...  (Note
            that this is NOT a term used by other standards bodies, such as ISO).
            [RFC 2277]

       EUC Extended Unix Character.  See ISO-2022.

       ISO-2022
           A CES that was carefully designed to coexist with
           ASCII.  There are a 7 bit version and an 8 bit ver-
           sion.

           The 7 bit version switches character set via escape
           sequence so it cannot form a CCS.  Since this is more
           difficult to handle in programs than the 8 bit ver-
           sion, the 7 bit version is not very popular except for
           iso-2022-jp, the de facto standard CES for e-mails.

           The 8 bit version can form a CCS.  EUC and ISO-8859
           are two examples thereof.  Pre-5.6 perl could use them
           as string literals.

       UCS Short for Universal Character Set.  When you say just
           UCS, it means Unicode.

       UCS-2
           ISO/IEC 10646 encoding form: Universal Character Set
           coded in two octets.

       Unicode
           A character set that aims to include all character
           repertoires of the world.  Many character sets in var-
           ious national as well as industrial standards have
           become, in a way, just subsets of Unicode.

       UTF Short for Unicode Transformation Format.  Determines
           how to map a Unicode character into a byte sequence.

       UTF-16
           A UTF in 16-bit encoding.  Can either be in big endian
           or little endian.  The big endian version is called
           UTF-16BE (equal to UCS-2 + surrogate support) and the
           little endian version is called UTF-16LE.

See Also
       Encode, Encode::Byte, Encode::CN, Encode::JP, Encode::KR,
       Encode::TW, Encode::EBCDIC, Encode::Symbol
       Encode::MIME::Header, Encode::Guess

References




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       ECMA
           European Computer Manufacturers Association
           <http://www.ecma.ch>;

           ECMA-035 (eq "ISO-2022")
               <http://www.ecma.ch/ecma1/STAND/ECMA-035.HTM>;

               The specification of ISO-2022 is available from
               the link above.

       IANA
           Internet Assigned Numbers Authority
           <http://www.iana.org/>;

           Assigned Charset Names by IANA
               <http://www.iana.org/assignments/character-sets>;

               Most of the "canonical names" in Encode derive
               from this list so you can directly apply the
               string you have extracted from MIME header of
               mails and web pages.

       ISO International Organization for Standardization
           <http://www.iso.ch/>;

       RFC Request For Comments -- need I say more?
           <http://www.rfc-editor.org/>;, <http://www.rfc.net/>;,
           <http://www.faqs.org/rfcs/>;

       UC  Unicode Consortium <http://www.unicode.org/>;

           Unicode Glossary
               <http://www.unicode.org/glossary/>;

               The glossary of this document is based upon this
               site.

       Other Notable Sites


       czyborra.com
           <http://czyborra.com/>;

           Contains a a lot of useful information, especially
           gory details of ISO vs. vendor mappings.

       CJK.inf
           <http://www.oreilly.com/peo-
           ple/authors/lunde/cjk_inf.html>

           Somewhat obsolete (last update in 1996), but still
           useful.  Also try

           <ftp://ftp.oreilly.com/pub/examples/nutshell/cjkv/pdf/GB18030_Summary.pdf>;



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           You will find brief info on "EUC-CN", "GBK" and mostly
           on "GB 18030".

       Jungshik Shin's Hangul FAQ
           <http://jshin.net/faq>;

           And especially its subject 8.

           <http://jshin.net/faq/qa8.html>;

           A comprehensive overview of the Korean ("KS *") stan-
           dards.

       debian.org: "Introduction to i18n"
           A brief description for most of the mentioned CJK
           encodings is contained in
           <http://www.debian.org/doc/manu-
           als/intro-i18n/ch-codes.en.html>

       Offline sources


       "CJKV Information Processing" by Ken Lunde
           CJKV Information Processing 1999 O'Reilly & Associ-
           ates, ISBN : 1-56592-224-7

           The modern successor of "CJK.inf".

           Features a comprehensive coverage of CJKV character
           sets and encodings along with many other issues faced
           by anyone trying to better support CJKV lan-
           guages/scripts in all the areas of information pro-
           cessing.

           To purchase this book, visit
           <http://www.oreilly.com/catalog/cjkvinfo/>; or your
           favourite bookstore.




















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