CTandWC(3X11) X11R5 CTandWC(3X11)NAME
XCTWC, CT, WC - Compound text and wide character encoding
DESCRIPTION
In this implementation the communication codeset is Compound Text
encoding, abbreviated to CT, the internal processing codeset is wide
character encoding, abbreviated to WC. The CT and WC occurring wher‐
ever in this implementation is defined as following:
[1] The CT encoding conforms with X standard document "Compound Text
Encoding, Version 1.1" except:
Section 7. Directionality
Section 10. Extensions
The CT string is terminated with null character.
[2] The WC is restricted to the following part of ISO DIS
10646(UCS):
* canonical form, 4 octets(4-byte: group/plane/row/cell).
* in the next sentences all number is decimal, and default group
is 032, plane is 032.
* row 032 for ISO 8859-1(L.2,p18)
* right-hand half of row 033 for right half of ISO8859-2(L4,p18)
* right-hand half of row 040 for right half of ISO8859-5(S25.2,p19)
* right-hand half of row 042 for right half of ISO8859-7(S26.2,p19)
* right-hand half of row 044 for right half of ISO8859-6(S27.1,p19)
* left-hand half of row 059 for JIS X 0201(Private Use zone)
* I-11, plane 048 of group 032 for Chinese GB 2312(S9,p9)
* I-11, plane 064 of group 032 for Japanese JIS X 0208(S10,p9)
* I-10, plane 064 of group 032 for Japanese JIS X 0212(S10,p9)
* plane 080 of group 032 for Korean KS C5601(S10,p9)
where the numbers in parentheses are line#(L), section#(S) and
page#(p) in document of ISO DIS 10646(UCS), 4 November 1990.
The other registered charset in CT are put on the following
place of DIS 10646.
* right-hand half of row 034 for right half of ISO8859-3
* right-hand half of row 035 for right half of ISO8859-4
* right-hand half of row 036 for right half of ISO8859-9
The following Private Use planes and zones are used for User
Defined Character(UDC):
* planes 224 of group 032 to 255(32 planes)
* left-hand half of row 052 of plane 032 of group 032 to 059(8 rows)
The WC string is terminated with WNULL character. The WNULL is
implementation-defined.
[3] Conversion between WC and CT.
The conversion between WC and CT will be done according to the
above correspondency. In CT a charset can be designated both to
graphic left(GL) and to graphic right(GR); in WC there is no
such GL and GR. So the conversion function translates GL and GR
of CT to same place of WC. In the reverse, the conversion func‐
tion always translates the WC to the GL of CT as following:
* plane 048 of Chinese to "ESC$(A", not "ESC$)A"
* plane 064 of Japanese to "ESC$(B", not "ESC$)B"
* plane 080 of Korean to "ESC$(C", not "ESC$)C"
* others one to one, no ambiguous.
SEE ALSO
ISO DIS 10646(UCS), 4 November 1990.
Compound Text Encoding, Version 1.1, X11R5.
CTandWC(3X11)
