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CONTENTS

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 exceptions).

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 general 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 different modules but you don't have to use Encode::XX to make them available for most cases. Encode.pm will automatically load those modules on demand.

Built-in Encodings

The following encodings are always available.

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, HTMLCREF or XMLCREF, ALL CHARACTERS will fall back to character 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 supported 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 implemented separately 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 characters.

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 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 windows-* . See also http://czyborra.com/charsets/codepages.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 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 alphanumerals 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.

This was once handled by Encode::Bytes but because of all those unusual specifications, Encode 2.20 has relocated the support to Encode::GSM0338. See Encode::GSM0338 for details.

gsm0338 support before 2.19

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
----------------------------------------------------------------

[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.

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. However, 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.

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. Audrey Tang may add support for this encoding in her module in future.

Various HP-UX encodings

The following are unsupported due to the lack of mapping 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 supports 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/seamonkey/source/intl/uconv/ucvlatin/vps.uf and http://lxr.mozilla.org/seamonkey/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 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/Public/MAPPINGS/VENDORS/APPLE/ .

(Mac) Indic encodings

The maps for the following are available at http://www.unicode.org/ but remain unsupported because those encodings need an algorithmical approach, currently unsupported by enc2xs:

MacDevanagari
MacGurmukhi
MacGujarati

For details, please see Unicode mapping issues and notes: at