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On Thu, 2003-11-13 at 09:05, Paul de Vrieze wrote: |
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> Isn't it true that it is possible to to encode the few 4 byte characters |
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> into a number of 2byte sequences. I think that is more than enough for |
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> most cases (who needs to read/write cjk anyway ;-) ) |
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According to my understanding of UCS, it doesn't seem to be the case. I |
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believe that UCS is the internal representation of a unicode character, |
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whereas UTF is the encoding of the character into octets for |
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representation on a computer. |
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As an example, a UCS4 character on one of the higher planes (the one |
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where extra CJK characters are placed), UTF-8 would require 6 |
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characters. UTF-8 (or -16 -32) are all able to represent the whole UCS4 |
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space. UCS2 does not do any "chaining" so it can only have, at most, 16 |
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bit characters (eg. 65535). UCS2 is a subset of UCS4[1]. |
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Of course, I've left out alot of details like UCS2 doesn't actually have |
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64K chars, etc. |
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With that said, most Linux machines that have wchar support, has wchar |
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defined as 4 bytes (int). So anything with wchar support probably |
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already uses 4 bytes. Maybe someone who has used wchar support can |
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comment on this. |
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Cheers, |
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[1] |
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http://www.gnuenterprise.org/doc/console-tools-libs/html/lct-4.html#sec-unicode |
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|
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-- |
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Alastair 'liquidx' Tse |
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>> Gentoo Developer |
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>> http://www.liquidx.net/ | http://dev.gentoo.org/~liquidx/ |
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