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1 | =head1 NAME |
2 | |
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3 | Encode::Supported -- Supported encodings by Encode |
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4 | |
5 | =head1 DESCRIPTION |
6 | |
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7 | =head2 Encoding Names |
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8 | |
9 | Encoding names are case insensitive. White space in names |
10 | is ignored. In addition an encoding may have aliases. |
11 | Each encoding has one "canonical" name. The "canonical" |
12 | name is chosen from the names of the encoding by picking |
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13 | the first in the following sequence (with a few exceptions). |
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14 | |
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15 | =over |
16 | |
17 | =item * |
18 | |
19 | The name used by the perl community. That includes 'utf8' and 'ascii'. |
20 | Unlike aliases, canonical names directly reaches the method so such |
21 | frequently used words like 'utf8' should do without alias lookups. |
22 | |
23 | =item * |
24 | |
25 | The MIME name as defined in IETF RFCs This includes all "iso-"'s. |
26 | |
27 | =item * |
28 | |
29 | The name in the IANA registry. |
30 | |
31 | =item * |
32 | |
33 | The name used by the organization that defined it. |
34 | |
35 | =back |
36 | |
37 | In case I<de jure> canonical names differ from that of the Encode |
38 | module, they are always aliased if it ever be implemented. So you can |
39 | safely tell if a given encoding is implemented or not just by passing |
40 | the canonical name. |
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41 | |
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42 | Because of all the alias issues, and because in the general case |
43 | encodings have state, "Encode" uses the encoding object internally |
44 | once an operation is in progress. |
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45 | |
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46 | =head1 Supported Encodings |
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47 | |
48 | As of Perl 5.8.0, at least the following encodings are recognized. |
49 | Note that unless otherwise specified, they are all case insensitive |
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50 | (via alias) and all occurrance of spaces are replaced with '-'. In |
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51 | other words, "ISO 8859 1" and "iso-8859-1" are identical. |
52 | |
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53 | Encodings are categorized and implemented in several different modules |
54 | but you don't have to C<use Encode::XX> to make them available for |
55 | most cases. Encode.pm will automatically load those modules in need. |
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56 | |
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57 | =head2 Built-in Encodings |
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58 | |
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59 | The following encodings are always available. |
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60 | |
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61 | Canonical Aliases Comments & References |
62 | ---------------------------------------------------------------- |
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63 | ascii US-ascii [ECMA] |
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64 | iso-8859-1 latin1 [ISO] |
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65 | utf8 UTF-8 [RFC2279] |
c731e18e |
66 | ---------------------------------------------------------------- |
67 | |
68 | |
69 | =head2 Encode::Unicode -- other Unicode encodings |
70 | |
71 | Unicode coding schemes other than native utf8 are supported by |
72 | Encode::Unicode which will be autoloaded on demand. |
73 | |
74 | ---------------------------------------------------------------- |
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75 | UCS-2BE UCS-2, iso-10646-1 [IANA, UC] |
76 | UCS-2LE [UC] |
77 | UTF-16 [UC] |
78 | UTF-16BE [UC] |
79 | UTF-16LE [UC] |
80 | UTF-32 [UC] |
81 | UTF-32BE [UC] |
82 | UTF-32LE [UC] |
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83 | ---------------------------------------------------------------- |
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84 | |
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85 | To find how those (UCS-2|UTF-(16|32))(LE|BE)? differ to one another, |
86 | see L<Encode::Unicode>. |
87 | |
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88 | =head2 Encode::Byte -- Extended ASCII |
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89 | |
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90 | Encode::Byte implements most of single-byte encodings except for |
91 | Symbols and EBCDIC. The following encodings are based single-byte |
92 | encoding implemented as extended ASCII. For most cases it uses |
93 | \x80-\xff (upper half) to map non-ASCII characters. |
94 | |
95 | =over 2 |
96 | |
97 | =item ISO-8859 and corresponding vendor mappings |
98 | |
99 | Since there are so many, They are presented in table format with |
100 | Languages and corresponding encoding names by vendors. Note the table |
101 | is sorted in order of ISO-8859 and the corresponding vendor mappings |
102 | are slightly different from that of ISO. See |
103 | L<http://czyborra.com/charsets/iso8859.html> for details. |
104 | |
105 | Lang/Regions ISO/Other Std. DOS Windows Macintosh Others |
106 | ---------------------------------------------------------------- |
107 | N. America (ASCII) cp437 AdobeStandardEncoding |
108 | cp863 (DOSCanadaF) |
109 | W. Europe (iso-8859-1) cp850 cp1252 MacRoman nextstep |
110 | hp-roman8 |
111 | cp860 (DOSPortuguese) |
112 | CE. Europe iso-8859-2 cp852 cp1250 MacCentralEurRoman |
113 | MacCroatian |
114 | MacRomanian |
115 | MacRumanian |
116 | Latin3(*3) iso-8859-3 |
117 | Latin4(*4) iso-8859-4 |
118 | Cyrillics iso-8859-5 cp855 cp1251 MacCyrillic |
119 | (Also see next section) cp866 MacUkrainian |
120 | Arabic iso-8859-6 cp864 cp1256 MacArabic |
121 | cp1006 MacFarsi |
122 | Greek iso-8859-7 cp737 cp1253 MacGreek |
123 | cp869 (DOSGreek2) |
124 | Hebrew iso-8859-8 cp862 cp1255 MacHebrew |
125 | Turkish iso-8859-9 cp857 cp1254 MacTurkish |
126 | Nordics iso-8859-10 cp865 |
127 | cp861 MacIcelandic |
128 | MacSami |
129 | Thai iso-8859-11 cp874 MacThai |
130 | (iso-8859-12 is nonexistent. Reserved for Indics?) |
131 | Baltics iso-8859-13 cp775 cp1257 |
132 | Celtics iso-8859-14 |
133 | Latin9(*15) iso-8859-15 |
134 | Latin10 iso-8859-16 |
135 | Vietnamese viscii cp1258 MacVietnamese |
136 | ---------------------------------------------------------------- |
137 | |
138 | (*3) Esperanto, Maltese, and Turkish. Turkish is now on 8859-5 |
139 | (*4) Baltics. Now on 8859-10 |
140 | (*9) Nicknamed Latin0; Euro sign as well as French and Finnish |
141 | letters that are missing from 8859-1 are added. |
142 | |
143 | All cp* are also available as ibm-*, ms-*, and windows-* . See also |
144 | L<http://czyborra.com/charsets/codepages.html>. |
145 | |
146 | Macintosh encodings don't seem to be registered in such entities as |
147 | IANA. "Canonical" names in Encode are based upon Apple's Tech Note |
148 | 1150. See L<http://developer.apple.com/technotes/tn/tn1150.html> |
149 | for details |
150 | |
151 | =item KOI8 - De Facto Standard for Cyrillic world |
152 | |
153 | Though ISO-8859 does have ISO-8859, KOI8 series is far more popular |
154 | in the Net. L<Encode> comes with the following KOI charsets. for |
155 | gory details, See <http://czyborra.com/charsets/cyrillic.html> for |
156 | details. |
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157 | |
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158 | ---------------------------------------------------------------- |
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159 | koi8-f |
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160 | koi8-r cp878 [RFC1489] |
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161 | koi8-u [RFC2319] |
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162 | |
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163 | =item gsm0338 - Hentai Latin 1 |
164 | |
165 | GSM0338 is for GSM handsets. Though it shares alpanumerals with ASCII, |
166 | control character ranges and other parts are mapped very differently, |
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167 | presumablly to store Greek and Cyrillic alphabets. This one is also |
168 | covered in Encode::Byte even thought this one does not comply extended |
169 | ASCII. |
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170 | |
171 | =back |
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172 | |
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173 | =head2 The CJK: Chinese, Japanese, Korean (Multibyte) |
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174 | |
175 | Note Vietnamese is listed above. Also read "Encoding vs Charset" |
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176 | below. Also note these are implemented in distinct module by |
177 | languages, due the the size concerns. Please also refer to their |
178 | respective document pages. |
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179 | |
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180 | =over 4 |
181 | |
182 | =item Encode::CN -- Continental China |
183 | |
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184 | Standard DOS/Win Macintosh Comment/Reference |
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185 | ---------------------------------------------------------------- |
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186 | euc-cn(*1) MacChineseSimp |
187 | (gbk) cp936 (*2) |
188 | gb12345-raw { GB12345 without CES } |
189 | gb2312-raw { GB2312 without CES } |
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190 | hz |
191 | iso-ir-165 |
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192 | ---------------------------------------------------------------- |
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193 | |
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194 | (*1) GB2312 is aliased to this. see L<Microsoft-related naming mess> |
195 | (*2) gbk is aliased to this. see L<Microsoft-related naming mess> |
196 | |
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197 | =item Encode::JP -- Japan |
198 | |
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199 | Standard DOS/Win Macintosh Comment/Reference |
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200 | ---------------------------------------------------------------- |
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201 | euc-jp |
202 | shiftjis cp932 macJapanese |
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203 | 7bit-jis |
204 | euc-jp |
205 | iso-2022-jp [RFC1468] |
206 | iso-2022-jp-1 [RFC2237] |
207 | jis0201-raw { JIS X 0201 (roman + halfwidth kana) without CES } |
208 | jis0208-raw { JIS X 0208 (Kanji + fullwidth kana) without CES } |
209 | jis0212-raw { JIS X 0212 (Extended Kanji) without CES } |
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210 | ---------------------------------------------------------------- |
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211 | |
212 | =item Encode::KR -- Korea |
213 | |
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214 | Standard DOS/Win Macintosh Comment/Reference |
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215 | ---------------------------------------------------------------- |
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216 | euc-kr MacKorean [RFC1557] |
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217 | cp949 (*) |
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218 | iso-2022-kr [RFC1557] |
219 | johab [KS X 1001:1998, Annex 3] |
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220 | ksc5601-raw { KSC5601 without CES } |
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221 | ---------------------------------------------------------------- |
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222 | |
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223 | (*) ks_c_5601-1987, (x-)?windows-949, and uhc are aliased to |
224 | this. See below. |
225 | |
226 | |
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227 | =item Encode::TW -- Taiwan |
228 | |
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229 | Standard DOS/Win Macintosh Comment/Reference |
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230 | ---------------------------------------------------------------- |
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231 | big5 cp950 MacChineseTrad |
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232 | big5-hkscs |
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233 | ---------------------------------------------------------------- |
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234 | |
235 | =item Encode::HanExtra -- More Chinese via CPAN |
236 | |
237 | Due to size concerns, additional Chinese encodings below are |
238 | distributed separately on CPAN, under the name Encode::HanExtra. |
239 | |
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240 | Standard DOS/Win Macintosh Comment/Reference |
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241 | ---------------------------------------------------------------- |
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242 | gb18030 |
243 | euc-tw |
244 | big5plus |
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245 | ---------------------------------------------------------------- |
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246 | |
247 | =back |
248 | |
249 | =head2 Miscellaneous encodings |
250 | |
251 | =over 4 |
252 | |
253 | =item Encode::EBCDIC |
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254 | |
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255 | See L<perlebcdic> for details. |
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256 | |
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257 | ---------------------------------------------------------------- |
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258 | cp37 |
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259 | cp500 |
260 | cp875 |
261 | cp1026 |
262 | cp1047 |
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263 | posix-bc |
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264 | ---------------------------------------------------------------- |
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265 | |
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266 | =item Encode::Symbols |
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267 | |
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268 | For symbols and dingbats. |
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269 | |
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270 | ---------------------------------------------------------------- |
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271 | symbol |
272 | dingbats |
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273 | MacDingbats |
274 | AdobeZdingbat |
275 | AdobeSymbol |
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276 | ---------------------------------------------------------------- |
277 | |
278 | =back |
279 | |
280 | =head1 Unsupported encodings |
281 | |
282 | The following are not supported as yet. Some because they are rarely |
283 | usede, some because of technical difficulty. They may be supported by |
284 | external modules via CPAN in future, however. |
285 | |
286 | =over 4 |
287 | |
288 | =item ISO-2022-JP-2 [RFC1554] |
289 | |
290 | Not very popular yet. Needs Unicode Database or equivalent to |
291 | implement encode() (Because it includes JIS X 0208/0212, KSC5601, and |
292 | GB2312 sumulteniously, which code points in unicode overlap. So you |
293 | need to lookup the database to determine what character set a given |
294 | Unicode character should belong). |
295 | |
296 | =item ISO-2022-CN [RFC1922] |
297 | |
298 | Not very popular. Needs CNS 11643-1 and 2 which are not available in |
299 | this module. CNS 11643 is supported (via euc-tw) in |
300 | Encode::HanExtra. Autrijus may add support for this encoding in his |
301 | module in future |
302 | |
303 | =item various UP-UX encodings |
304 | |
305 | The following are unsoported due to the lack of mapping data. |
306 | |
307 | '8' - arabic8, greek8, hebrew8, kana8, thai8, and turkish8 |
308 | '15' - japanese15, korean15, and roi15 |
309 | |
310 | =item Cyrillic encoding ISO-IR-111 |
311 | |
312 | Anton doubts its usefulness. |
313 | |
314 | =item ISO-8859-8-1 [Hebrew] |
315 | |
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316 | None of the Encode team knows Hebrew enough (ISO-8859-8, cp1255 and |
317 | MacHebrew are supported because and just because there were mappings |
318 | available at L<http://www.unicode.org/>). Contribution welcome. |
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319 | |
320 | =item Thai encoding TCVN |
321 | |
322 | Ditto. |
323 | |
324 | =item Vietnamese encodings VPS |
325 | |
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326 | Though Jungshik has reported that mozilla supports this encoding, It was too late for us to add one. In future via a separate module. See |
327 | L<http://lxr.mozilla.org/seamonkey/source/intl/uconv/ucvlatin/vps.uf> and |
328 | L<http://lxr.mozilla.org/seamonkey/source/intl/uconv/ucvlatin/vps.ut> |
329 | if you are interested in helping us. |
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330 | |
331 | =item various Mac encodings |
332 | |
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333 | The following are unsoported due to the lack of mapping data. |
334 | |
335 | MacArmenian, MacBengali, MacBurmese, MacEthiopic |
336 | MacExtArabic, MacGeorgian, MacKannada, MacKhmer |
337 | MacLaotian, MacMalayalam, MacMongolian, MacOriya |
338 | MacSinhalese, MacTamil, MacTelugu, MacTibetan |
339 | MacVietnamese |
340 | |
341 | The rest of which already available are based upon the vendor mappings at |
342 | L<http://www.unicode.org/Public/MAPPINGS/VENDORS/APPLE/> . |
343 | |
344 | =item (Mac) Indic encodings |
345 | |
346 | The maps for the following is available at L<http://www.unicode.org/> |
347 | but remains unsupport because those encordigs need algorithmical |
348 | approach, unsupported by F<enc2xs> |
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349 | |
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350 | MacDevanagari |
351 | MacGurmukhi |
352 | MacGujarati |
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353 | |
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354 | For details, please see C<Unicode mapping issues and notes:> at |
355 | L<http://www.unicode.org/Public/MAPPINGS/VENDORS/APPLE/DEVANAGA.TXT> . |
356 | |
357 | I believe this issue is prevalent not only for Mac Indics but also in |
358 | other Indic encodings but those mentions were the only Indic encodings |
359 | maps that I could find at L<http://www.unicode.org/> . |
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360 | |
361 | =back |
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362 | |
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363 | =head1 Encoding vs. Charset -- terminology |
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364 | |
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365 | We are used to using the term (character) I<encoding> and I<character set> |
366 | interchangeably. But just as using the term byte and character is |
367 | dangerous and should be differenciated when needed, we need to |
368 | differenciate I<encoding> and I<character set>. |
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369 | |
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370 | To understand that, it's follow how we make computers grok our characters. |
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371 | |
372 | =over 4 |
373 | |
374 | =item * |
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375 | |
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376 | First we start with which characters to include. We call this |
377 | collection of characters I<character repertoire>. |
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378 | |
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379 | =item * |
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380 | |
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381 | Then we have to give each character a unique ID so your computer can |
382 | tell the differnce from 'a' to 'A'. This itemized character |
383 | repartoire is now a I<character set>. |
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384 | |
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385 | =item * |
386 | |
387 | If your computer can grow the character set without further |
388 | proccessing, you can go ahead use it. This is called a I<coded |
389 | character set> (CCS) or I<raw character encoding>. ASCII is used this |
390 | way for most cases. |
391 | |
392 | =item * |
393 | |
394 | But in many cases especially multi-byte CJK encodings, you have to |
395 | tweak a little more. Your network connection may not accept any data |
396 | with the Most Significant Bit set, Your computer may not be able to |
397 | tell if a given byte is a whole character or just half of it. So you |
398 | have to I<encode> the character set to use it. |
399 | |
400 | A I<character encoding scheme> (CES) determines how to encode a given |
401 | character set, or a set of multiple character sets. 7bit ISO-2022 is |
402 | an example of CES. You switch between character sets via I<escape |
403 | sequence>. |
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404 | |
405 | =back |
406 | |
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407 | Technically, or Mathematically speaking, a character set encoded in |
408 | such a CES that maps character by character may form a CCS. EUC is such |
409 | an example. CES of EUC is as follows; |
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410 | |
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411 | =over 4 |
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412 | |
a999c27c |
413 | =item * |
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414 | |
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415 | Map ASCII unchanged. |
416 | |
417 | =item * |
418 | |
419 | Map such a character set that consists of 94 or 96 powered by N |
420 | members by adding 0x80 to each byte. |
421 | |
422 | =item * |
423 | |
424 | You can also use 0x8e and 0x8f to tell the following sequence of |
425 | characters belong to yet another character set. each following byte |
426 | is added by 0x80 |
427 | |
428 | =back |
429 | |
430 | By carefully looking at at the encoded byte sequence, you may find the |
431 | byte sequence conforms a unique number. In that sense EUC is a CCS |
432 | generated by a CES above from up to four CCS (complicated?). UTF-8 |
433 | falls into this category. See L<perlunicode/"UTF-8"> to find how |
434 | UTF-8 maps Unicode to a byte sequence. |
435 | |
436 | You may also find by now why 7bit ISO-2022 cannot conform a CCS. If |
437 | you look at a byte sequence \x21\x21, you can't tell if it is two !'s |
438 | or IDEOGRAPHIC SPACE. EUC maps the latter to \xA1\xA1 so you have no |
439 | trouble between "!!". and " " |
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440 | |
a63c962f |
441 | =head1 Encoding Classification (by Anton Tagunov and Dan Kogai) |
442 | |
443 | This section tries to classify the supported encodings by their |
444 | applicability for information exchange over the Internet and to |
445 | choose the most suitable aliases to name them in the context of |
446 | such communication. |
447 | |
67d7b5ef |
448 | =over 2 |
449 | |
450 | =item * |
451 | |
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452 | To (en|de) code Encodings marked as C<(**)>, You need |
a999c27c |
453 | C<Encode::HanExtra>, available from CPAN. |
67d7b5ef |
454 | |
455 | =back |
456 | |
a63c962f |
457 | Encoding names |
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458 | |
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459 | US-ASCII UTF-8 ISO-8859-* KOI8-R |
460 | Shift_JIS EUC-JP ISO-2022-JP ISO-2022-JP-1 |
461 | EUC-KR Big5 GB2312 |
a999c27c |
462 | |
463 | are registered to IANA as preferred MIME names and may probably |
464 | be used over the Internet. |
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465 | |
c731e18e |
466 | C<Shift_JIS> has been officialized by JIS X 0208:1997. |
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467 | L<Microsoft-related naming mess> gives details. |
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468 | |
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469 | C<GB2312> is the IANA name for C<EUC-CN>. |
470 | See L<Microsoft-related naming mess> for details. |
471 | |
472 | C<GB_2312-80> I<raw> encoding is available as C<gb2312-raw> |
f2a2953c |
473 | with Encode. See L<Encode::CN> for details. |
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474 | |
a63c962f |
475 | EUC-CN |
f2a2953c |
476 | KOI8-U [RFC2319] |
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477 | |
a999c27c |
478 | have not been registered with IANA (as of March 2002) but |
479 | seem to be supported by major web browsers. |
480 | IANA name for C<EUC-CN> is C<GB2312>. |
67d7b5ef |
481 | |
482 | KS_C_5601-1987 |
483 | |
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484 | is heavily misused. |
485 | See L<Microsoft-related naming mess> for details. |
486 | |
487 | C<KS_C_5601-1987> I<raw> encoding is available as C<kcs5601-raw> |
f2a2953c |
488 | with Encode. See L<Encode::KR> for details. |
489 | |
490 | UTF-16 UTF-16BE UTF-16LE |
491 | |
492 | are a IANA-registered C<charset>s. See [RFC 2781] for details. |
493 | Jungshik Shin reports that UTF-16 with a BOM is well accepted |
494 | by MS IE 5/6 and NS 4/6. Beware however that |
495 | |
496 | =over 2 |
497 | |
498 | =item * |
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499 | |
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500 | C<UTF-16> support in any software you're going to be |
501 | using/interoperating with has probably been less tested |
502 | then C<UTF-8> support |
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503 | |
f2a2953c |
504 | =item * |
505 | |
c731e18e |
506 | C<UTF-8> coded data seamlessly passes traditional |
507 | command piping (C<cat>, C<more>, etc.) while C<UTF-16> coded |
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508 | data is likely to cause confusion (with it's zero bytes, |
509 | for example) |
510 | |
511 | =item * |
512 | |
513 | it is beyond the power of words to describe the way HTML browsers |
c731e18e |
514 | encode non-C<ASCII> form data. To get a general impression visit |
f2a2953c |
515 | L<http://ppewww.ph.gla.ac.uk/~flavell/charset/form-i18n.html>. |
c731e18e |
516 | While encoding of form data has stabilized for C<UTF-8> coded pages |
f2a2953c |
517 | (at least IE 5/6, NS 6, Opera 6 behave consitently), be sure to |
518 | expect fun (and cross-browser discrepancies) with C<UTF-16> coded |
519 | pages! |
520 | |
521 | =back |
522 | |
523 | The rule of thumb is to use C<UTF-8> unless you know what |
c731e18e |
524 | you're doing and unless you really benefit from using C<UTF-16>. |
a999c27c |
525 | |
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526 | |
f2a2953c |
527 | ISO-IR-165 [RFC1345] |
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528 | GBK |
529 | VISCII |
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530 | GB 12345 |
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531 | GB 18030 (**) (see links bellow) |
532 | EUC-TW (**) |
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533 | |
534 | are totally valid encodings but not registered at IANA. |
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535 | The names under which they are listed here are probably the |
536 | most widely-known names for these encodings and are recommended |
537 | names. |
538 | |
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539 | BIG5PLUS (**) |
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540 | |
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541 | is a bit proprietary name. |
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542 | |
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543 | =head2 Microsoft-related naming mess |
544 | |
545 | Microsoft products misuse the following names: |
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546 | |
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547 | =over 2 |
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548 | |
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549 | =item KS_C_5601-1987 |
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550 | |
a999c27c |
551 | Microsoft extension to C<EUC-KR>. |
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552 | |
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553 | Proper names: C<CP949>, C<UHC>, C<x-windows-949> (as used by Mozilla). |
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554 | |
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555 | See L<http://lists.w3.org/Archives/Public/ietf-charsets/2001AprJun/0033.html> |
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556 | for details. |
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557 | |
f2a2953c |
558 | Encode aliases C<KS_C_5601-1987> to C<cp949> to reflect this common |
559 | misusage. I<Raw> C<KS_C_5601-1987> encoding is available as |
560 | C<kcs5601-raw>. |
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561 | |
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562 | See L<Encode::KR> for details. |
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563 | |
a999c27c |
564 | =item GB2312 |
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565 | |
a999c27c |
566 | Microsoft extension to C<EUC-CN>. |
a63c962f |
567 | |
a999c27c |
568 | Proper names: C<CP936>, C<GBK>. |
a63c962f |
569 | |
a999c27c |
570 | C<GB2312> has been registered in the C<EUC-CN> meaning at |
571 | IANA. This has partially repaired the situation: Microsoft's |
572 | C<GB2312> has become a superset of the official C<GB2312>. |
67d7b5ef |
573 | |
a999c27c |
574 | Encode aliases C<GB2312> to C<euc-cn> in full agreement with |
575 | IANA registration. C<cp936> is supported separately. |
f2a2953c |
576 | I<Raw> C<GB_2312-80> encoding is available as C<gb2312-raw>. |
a999c27c |
577 | |
f2a2953c |
578 | See L<Encode::CN> for details. |
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579 | |
580 | =item Big5 |
581 | |
582 | Microsoft extension to C<Big5>. |
583 | |
584 | Proper name: C<CP950>. |
585 | |
586 | Encode separately supports C<Big5> and C<cp950>. |
587 | |
588 | =item Shift_JIS |
589 | |
590 | Microsoft's understanding of C<Shift_JIS>. |
591 | |
592 | JIS has not endorsed the full Microsoft standard however. |
593 | The official C<Shift_JIS> includes only JIS X 0201 and JIS X 0208 |
594 | subsets, while Microsoft has always been meaning C<Shift_JIS> to |
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595 | encode a wider character repertoire. See C<IANA> registration for |
c731e18e |
596 | C<Windows-31J>. |
a999c27c |
597 | |
598 | As a historical predecessor Microsoft's variant |
599 | probably has more rights for the name, albeit it may be objected |
600 | that Microsoft shouldn't have used JIS as part of the name |
601 | in the first place. |
602 | |
fcb875d4 |
603 | Unambiguous name: C<CP932>. C<IANA> name (not used?): C<Windows-31J>. |
a999c27c |
604 | |
605 | Encode separately supports C<Shift_JIS> and C<cp932>. |
606 | |
607 | =back |
608 | |
609 | =head1 Glossary |
610 | |
611 | =over 2 |
612 | |
613 | =item character repertoire |
614 | |
615 | A collection of unique characters. A I<character> set in the most |
616 | strict sense. At this stage characters are not numberd. |
617 | |
618 | =item coded character set (CCS) |
619 | |
620 | A character set that is mapped in a way computers can use directly. |
621 | Many character encodings including EUC falls in this category. |
622 | |
623 | =item character encoding scheme (CES) |
624 | |
625 | An algorithm to map a character set to a byte sequence. You don't |
626 | have to be able to tell which character set a given byte sequence |
627 | belongs. 7-bit ISO-2022 is a CES but it cannot be a CCS. EUC is an |
628 | example of being both a CCS and CES. |
629 | |
f2a2953c |
630 | =item charset (in MIME context) |
631 | |
632 | has long been used in the meaning of C<encoding>, CES. |
633 | |
634 | While C<character set> word combination has lost this meaning |
635 | in MIME context since [RFC 2130], C<charset> abbreviation has |
636 | retained it. This is how [RFC 2277], [RFC 2278] bless C<charset>: |
637 | |
638 | |
639 | This document uses the term "charset" to mean a set of rules for |
640 | mapping from a sequence of octets to a sequence of characters, such |
641 | as the combination of a coded character set and a character encoding |
642 | scheme; this is also what is used as an identifier in MIME "charset=" |
643 | parameters, and registered in the IANA charset registry ... (Note |
644 | that this is NOT a term used by other standards bodies, such as ISO). |
645 | [RFC 2277] |
646 | |
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647 | =item EUC |
648 | |
649 | Extended Unix Character. See ISO-2022 |
650 | |
651 | =item ISO-2022 |
652 | |
653 | A CES that was carefully designed to coexist with ASCII. There are 7 |
f2a2953c |
654 | bit version and 8 bit version. |
655 | |
656 | 7 bit version switches character set via escape sequence so this |
657 | cannot form a CCS. Since this is more difficult to handle in programs |
658 | than the 8 bit version, 7 bit version is not very popular except for |
659 | iso-2022-jp, the de facto standard CES for e-mails. |
660 | |
661 | 8 bit version can conform a CCS. EUC and ISO-8859 are two examples |
662 | thereof. pre-5.6 perl could use them as string literals. |
a999c27c |
663 | |
664 | =item UCS |
665 | |
666 | Short for I<Universal Character Set>. When you say just UCS, it means |
667 | I<Unicode> |
668 | |
669 | =item UCS-2 |
670 | |
671 | ISO/IEC 10646 encoding form: Universal Character Set coded in two |
672 | octets. |
673 | |
674 | =item Unicode |
675 | |
f2a2953c |
676 | A Character Set that aims to include all character repertoire of the |
677 | world. Many character sets in various national as well as industorial |
678 | standards have become, in a way, just subsets of Unicode. |
a999c27c |
679 | |
680 | =item UTF |
681 | |
f2a2953c |
682 | Short for I<Unicode Transformation Format>. Determines how to map a |
a999c27c |
683 | unicode character into byte sequnece. |
684 | |
685 | =item UTF-16 |
686 | |
687 | A UTF in 16-bit encoding. Can either be in big endian or little |
f2a2953c |
688 | endian. Big endian version is called UTF-16BE (equals to UCS-2 + |
689 | Surrogate Support) and little endian version is UTF-16LE. |
67d7b5ef |
690 | |
691 | =back |
5d030b67 |
692 | |
693 | =head1 See Also |
694 | |
5129552c |
695 | L<Encode>, |
696 | L<Encode::Byte>, |
a63c962f |
697 | L<Encode::CN>, L<Encode::JP>, L<Encode::KR>, L<Encode::TW>, |
5129552c |
698 | L<Encode::EBCDIC>, L<Encode::Symbol> |
5d030b67 |
699 | |
a999c27c |
700 | =head1 References |
701 | |
702 | =over 2 |
703 | |
704 | =item ECMA |
705 | |
706 | European Computer Manufacturers Association |
707 | L<http://www.ecma.ch> |
708 | |
709 | =over 2 |
710 | |
711 | =item EMCA-035 (eq C<ISO-2022>) |
712 | |
713 | L<http://www.ecma.ch/ecma1/STAND/ECMA-035.HTM> |
714 | |
715 | The very dspecification of ISO-2022 is available from the link above. |
716 | |
717 | =back |
718 | |
719 | =item IANA |
720 | |
721 | Internet Assigned Numbers Authority |
722 | L<http://www.iana.org/> |
723 | |
724 | =over 2 |
725 | |
726 | =item Assigned Charset Names by IANA |
727 | |
728 | L<http://www.iana.org/assignments/character-sets> |
729 | |
730 | Most of the C<canonical names> in Encode derive from this list |
731 | so you can directly apply the string you have extracted from MIME |
732 | header of mails and we pages. |
733 | |
734 | =back |
735 | |
736 | =item ISO |
737 | |
738 | International Organization for Standardization |
739 | L<http://www.iso.ch/> |
740 | |
741 | =item RFC |
742 | |
743 | Request For Comment -- need I say more? |
f2a2953c |
744 | L<http://www.rfc.net/>, L<http://www.faqs.org/rfcs/> |
a999c27c |
745 | |
746 | =item UC |
747 | |
748 | Unicode Consortium |
749 | L<http://www.unicode.org/> |
750 | |
751 | =over 2 |
752 | |
753 | =item Unicode Glossary |
754 | |
755 | L<http://www.unicode.org/glossary/> |
756 | |
757 | The glossary of this document is based opon this site. |
758 | |
759 | =back |
760 | |
761 | =back |
762 | |
763 | =head2 Other Notable Sites |
764 | |
765 | =over 2 |
766 | |
767 | =item czyborra.com |
768 | |
f2a2953c |
769 | L<http://czyborra.com/> |
a999c27c |
770 | |
771 | Contains a a lot of useful information, especially gory details of ISO |
772 | vs. vendor mappings. |
773 | |
774 | =item CJK.inf |
775 | |
776 | L<http://www.oreilly.com/people/authors/lunde/cjk_inf.html> |
777 | |
778 | Somewhat obsolete (last update in 1996), but still useful. Also try |
779 | |
780 | L<ftp://ftp.oreilly.com/pub/examples/nutshell/cjkv/pdf/GB18030_Summary.pdf> |
781 | |
782 | You will find brief info on C<EUC-CN>, C<GBK> and mostly on C<GB 18030> |
783 | |
f2a2953c |
784 | =item Jungshik Shin's Hangul FAQ |
785 | |
786 | L<http://jshin.net/faq> |
787 | |
788 | And especially it's subject 8 |
789 | |
790 | L<http://jshin.net/faq/qa8.html> |
791 | |
792 | a comprehensive overview of the Korean (C<KS *>) standards. |
793 | |
794 | =back |
795 | |
796 | =head2 Offline sources |
797 | |
798 | =over 2 |
799 | |
800 | =item C<CJKV Information Processing> by Ken Lunde |
801 | |
802 | CJKV Information Processing |
803 | 1999 O'Reilly & Associates, ISBN : 1-56592-224-7 |
804 | |
805 | The modern successor of the C<CJK.inf>. |
806 | |
807 | Features a comprehensive coverage on CJKV character sets and |
808 | encodings along with many other issues faced by anyone trying |
809 | to better support CJKV languages/scripts in all the areas of |
810 | information processing. |
811 | |
812 | To purchase this book visit |
813 | L<http://www.oreilly.com/catalog/cjkvinfo/> |
814 | |
a999c27c |
815 | =back |
816 | |
5d030b67 |
817 | =cut |
67d7b5ef |
818 | |
819 | I could not find this page because the hostname doesn't resolve! |
820 | |
821 | Brief description for most of the mentioned CJK encodings |
822 | L<http://www.debian.org.ru/doc/manuals/intro-i18n/ch-codes.html> |