encode::supported.3

视频监控网络部分的协议ddns,的模块的实现代码,请大家大胆指正.

One possible workaround is
.Sp
.Vb 3
\&   $gsm =~ s/\ex00\ez/\ex00\ex00/;
\&   $uni = decode("gsm0338", $gsm);
\&   $uni .= "\exA0" if $gsm =~ /\ex1B\ez/;
.Ve
.Sp
Note that the Encode implementation of \s-1GSM0338\s0 does not implement the
reuse of Latin capital letters as Greek capital letters (for example,
the 0x5A is U+005A (\s-1LATIN\s0 \s-1CAPITAL\s0 \s-1LETTER\s0 Z), not U+0396 (\s-1GREEK\s0 \s-1CAPITAL\s0
\&\s-1LETTER\s0 \s-1ZETA\s0).
.Sp
The \s-1GSM0338\s0 is also covered in Encode::Byte even though it is not
an \*(L"extended \s-1ASCII\s0\*(R" encoding.
.Sh "\s-1CJK:\s0 Chinese, Japanese, Korean (Multibyte)"
.IX Subsection "CJK: Chinese, Japanese, Korean (Multibyte)"
Note that Vietnamese is listed above.  Also read \*(L"Encoding vs Charset\*(R"
below.  Also note that these are implemented in distinct modules by
countries, due to the size concerns (simplified Chinese is mapped
to '\s-1CN\s0', continental China, while traditional Chinese is mapped to
\&'\s-1TW\s0', Taiwan).  Please refer to their respective documentation pages.
.IP "Encode::CN \*(-- Continental China" 2
.IX Item "Encode::CN  Continental China"
.Vb 9
\&  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>
.Ve
.IP "Encode::JP \*(-- Japan" 2
.IX Item "Encode::JP  Japan"
.Vb 11
\&  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 }
\&  \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
.Ve
.IP "Encode::KR \*(-- Korea" 2
.IX Item "Encode::KR  Korea"
.Vb 8
\&  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.
.Ve
.IP "Encode::TW \*(-- Taiwan" 2
.IX Item "Encode::TW  Taiwan"
.Vb 5
\&  Standard      DOS/Win Macintosh                Comment/Reference
\&  \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
\&  big5\-eten     cp950   MacChineseTrad {big5 aliased to big5\-eten}
\&  big5\-hkscs                              
\&  \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
.Ve
.IP "Encode::HanExtra \*(-- More Chinese via \s-1CPAN\s0" 2
.IX Item "Encode::HanExtra  More Chinese via CPAN"
Due to the size concerns, additional Chinese encodings below are
distributed separately on \s-1CPAN\s0, under the name Encode::HanExtra.
.Sp
.Vb 8
\&  Standard      DOS/Win Macintosh                Comment/Reference
\&  \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
\&  big5ext                                   CMEX\*(Aqs Big5e Extension
\&  big5plus                                  CMEX\*(Aqs Big5+ Extension
\&  cccii         Chinese Character Code for Information Interchange
\&  euc\-tw                             EUC (Extended Unix Character)
\&  gb18030                          GBK with Traditional Characters
\&  \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
.Ve
.IP "Encode::JIS2K \*(-- \s-1JIS\s0 X 0213 encodings via \s-1CPAN\s0" 2
.IX Item "Encode::JIS2K  JIS X 0213 encodings via CPAN"
Due to size concerns, additional Japanese encodings below are
distributed separately on \s-1CPAN\s0, under the name Encode::JIS2K.
.Sp
.Vb 8
\&  Standard      DOS/Win Macintosh                Comment/Reference
\&  \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
\&  euc\-jisx0213
\&  shiftjisx0123
\&  iso\-2022\-jp\-3
\&  jis0213\-1\-raw
\&  jis0213\-2\-raw
\&  \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
.Ve
.Sh "Miscellaneous encodings"
.IX Subsection "Miscellaneous encodings"
.IP "Encode::EBCDIC" 2
.IX Item "Encode::EBCDIC"
See perlebcdic for details.
.Sp
.Vb 8
\&  \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
\&  cp37
\&  cp500  
\&  cp875  
\&  cp1026  
\&  cp1047  
\&  posix\-bc
\&  \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
.Ve
.IP "Encode::Symbols" 2
.IX Item "Encode::Symbols"
For symbols  and dingbats.
.Sp
.Vb 7
\&  \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
\&  symbol
\&  dingbats
\&  MacDingbats
\&  AdobeZdingbat
\&  AdobeSymbol
\&  \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
.Ve
.IP "Encode::MIME::Header" 2
.IX Item "Encode::MIME::Header"
Strictly speaking, \s-1MIME\s0 header encoding documented in \s-1RFC\s0 2047 is more
of encapsulation than encoding.  However, their support in modern
world is imperative so they are supported.
.Sp
.Vb 5
\&  \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
\&  MIME\-Header                                            [RFC2047]
\&  MIME\-B                                                 [RFC2047]
\&  MIME\-Q                                                 [RFC2047]
\&  \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
.Ve
.IP "Encode::Guess" 2
.IX Item "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 \fIsuspects\fR.  See
Encode::Guess for details.
.SH "Unsupported encodings"
.IX Header "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 \s-1CPAN\s0 in the future, however.
.IP "\s-1ISO\-2022\-JP\-2\s0 [\s-1RFC1554\s0]" 2
.IX Item "ISO-2022-JP-2 [RFC1554]"
Not very popular yet.  Needs Unicode Database or equivalent to
implement \fIencode()\fR (because it includes \s-1JIS\s0 X 0208/0212, \s-1KSC5601\s0, and
\&\s-1GB2312\s0 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).
.IP "\s-1ISO\-2022\-CN\s0 [\s-1RFC1922\s0]" 2
.IX Item "ISO-2022-CN [RFC1922]"
Not very popular.  Needs \s-1CNS\s0 11643\-1 and \-2 which are not available in
this module.  \s-1CNS\s0 11643 is supported (via euc-tw) in Encode::HanExtra.
Autrijus Tang may add support for this encoding in his module in future.
.IP "Various HP-UX encodings" 2
.IX Item "Various HP-UX encodings"
The following are unsupported due to the lack of mapping data.
.Sp
.Vb 2
\&  \*(Aq8\*(Aq  \- arabic8, greek8, hebrew8, kana8, thai8, and turkish8
\&  \*(Aq15\*(Aq \- japanese15, korean15, and roi15
.Ve
.IP "Cyrillic encoding \s-1ISO\-IR\-111\s0" 2
.IX Item "Cyrillic encoding ISO-IR-111"
Anton Tagunov doubts its usefulness.
.IP "\s-1ISO\-8859\-8\-1\s0 [Hebrew]" 2
.IX Item "ISO-8859-8-1 [Hebrew]"
None of the Encode team knows Hebrew enough (\s-1ISO\-8859\-8\s0, cp1255 and
MacHebrew are supported because and just because there were mappings
available at <http://www.unicode.org/>).  Contributions welcome.
.IP "\s-1ISIRI\s0 3342, Iran System, \s-1ISIRI\s0 2900 [Farsi]" 2
.IX Item "ISIRI 3342, Iran System, ISIRI 2900 [Farsi]"
Ditto.
.IP "Thai encoding \s-1TCVN\s0" 2
.IX Item "Thai encoding TCVN"
Ditto.
.IP "Vietnamese encodings \s-1VPS\s0" 2
.IX Item "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.
.IP "Various Mac encodings" 2
.IX Item "Various Mac encodings"
The following are unsupported due to the lack of mapping data.
.Sp
.Vb 5
\&  MacArmenian,  MacBengali,   MacBurmese,   MacEthiopic
\&  MacExtArabic, MacGeorgian,  MacKannada,   MacKhmer
\&  MacLaotian,   MacMalayalam, MacMongolian, MacOriya
\&  MacSinhalese, MacTamil,     MacTelugu,    MacTibetan
\&  MacVietnamese
.Ve
.Sp
The rest which are already available are based upon the vendor mappings
at <http://www.unicode.org/Public/MAPPINGS/VENDORS/APPLE/> .
.IP "(Mac) Indic encodings" 2
.IX Item "(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 \fIenc2xs\fR:
.Sp
.Vb 3
\&  MacDevanagari
\&  MacGurmukhi
\&  MacGujarati
.Ve
.Sp
For details, please see \f(CW\*(C`Unicode mapping issues and notes:\*(C'\fR at
<http://www.unicode.org/Public/MAPPINGS/VENDORS/APPLE/DEVANAGA.TXT> .
.Sp
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/> .
.SH "Encoding vs. Charset \*(-- terminology"
.IX Header "Encoding vs. Charset  terminology"
We are used to using the term (character) \fIencoding\fR and \fIcharacter
set\fR interchangeably.  But just as confusing the terms byte and
character is dangerous and the terms should be differentiated when
needed, we need to differentiate \fIencoding\fR and \fIcharacter set\fR.
.PP
To understand that, here is a description of how we make computers
grok our characters.
.IP "\(bu" 2
First we start with which characters to include.  We call this
collection of characters \fIcharacter repertoire\fR.
.IP "\(bu" 2
Then we have to give each character a unique \s-1ID\s0 so your computer can
tell the difference between 'a' and 'A'.  This itemized character
repertoire is now a \fIcharacter set\fR.
.IP "\(bu" 2
If your computer can grow the character set without further
processing, you can go ahead and use it.  This is called a \fIcoded
character set\fR (\s-1CCS\s0) or \fIraw character encoding\fR.  \s-1ASCII\s0 is used this
way for most cases.
.IP "\(bu" 2
But in many cases, especially multi-byte \s-1CJK\s0 encodings, you have to
tweak a little more.  Your network connection may not accept any data
with the Most Significant 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 \fIencode\fR the character set to use it.
.Sp
A \fIcharacter encoding scheme\fR (\s-1CES\s0) determines how to encode a given
character set, or a set of multiple character sets.  7bit \s-1ISO\-2022\s0 is
an example of a \s-1CES\s0.  You switch between character sets via \fIescape
sequences\fR.
.PP
Technically, or mathematically, speaking, a character set encoded in
such a \s-1CES\s0 that maps character by character may form a \s-1CCS\s0.  \s-1EUC\s0 is such
an example.  The \s-1CES\s0 of \s-1EUC\s0 is as follows:
.IP "\(bu" 2
Map \s-1ASCII\s0 unchanged.
.IP "\(bu" 2
Map such a character set that consists of 94 or 96 powered by N
members by adding 0x80 to each byte.
.IP "\(bu" 2
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.
.PP
By carefully looking at the encoded byte sequence, you can find that the
byte sequence conforms a unique number.  In that sense, \s-1EUC\s0 is a \s-1CCS\s0
generated by a \s-1CES\s0 above from up to four \s-1CCS\s0 (complicated?).  \s-1UTF\-8\s0
falls into this category.  See \*(L"\s-1UTF\-8\s0\*(R" in perlUnicode to find out how
\&\s-1UTF\-8\s0 maps Unicode to a byte sequence.
.PP
You may also have found out by now why 7bit \s-1ISO\-2022\s0 cannot comprise
a \s-1CCS\s0.  If you look at a byte sequence \ex21\ex21, you can't tell if
it is two !'s or \s-1IDEOGRAPHIC\s0 \s-1SPACE\s0.  \s-1EUC\s0 maps the latter to \exA1\exA1
so you have no trouble differentiating between \*(L"!!\*(R". and \*(L"\ \ \*(R".
.SH "Encoding Classification (by Anton Tagunov and Dan Kogai)"
.IX Header "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.
.IP "\(bu" 2
To (en|de)code encodings marked by \f(CW\*(C`(**)\*(C'\fR, you need 
\&\f(CW\*(C`Encode::HanExtra\*(C'\fR, available from \s-1CPAN\s0.
.PP
Encoding names
.PP
.Vb 3
\&  US\-ASCII    UTF\-8    ISO\-8859\-*  KOI8\-R
\&  Shift_JIS   EUC\-JP   ISO\-2022\-JP ISO\-2022\-JP\-1
\&  EUC\-KR      Big5     GB2312
.Ve
.PP
are registered with \s-1IANA\s0 as preferred \s-1MIME\s0 names and may
be used over the Internet.
.PP
\&\f(CW\*(C`Shift_JIS\*(C'\fR has been officialized by \s-1JIS\s0 X 0208:1997.