On Fri, 26 Oct 2001, Tomohiro KUBOTA wrote: > I found a problem on JIS X 0208 -> Unicode table in libX11 > (xc/lib/X11/lcUniConv/jisx0208.h). > > The reverse solidus in JIS X 0208 is mapped into U+005C > in the above file. Since JIS X 0208 is almost always used > with combined with ASCII, it causes a conflict between > reverse solidus in JIS X 0208 and ASCII. > > This is why GNU libc maps reverse solidus in JIS X 0208 > into U+FF3C (FULLWIDTH REVERSE SOLIDUS). Thus, the current > situation of libX11 causes a conflict of mapping tables > between GNU libc and XFree86. > > I found this bug when I input fullwidth reverse solidus > using Japanese XIM and XTerm under UTF-8 locale. > > I remember Markus Kuhn admited this is a problem, though I > cannot show the mail now....
I documented and discussed the issue in http://www.cl.cam.ac.uk/~mgk25/unicode.html#conv "The Unicode mapping tables also have to be slightly modified sometimes to preserve information in combination encodings. For example, the standard mappings provide round-trip compatibility for conversion chains ASCII to Unicode to ASCII as well as for JIS X 0208 to Unicode to JIS X 0208. However, the EUC-JP encoding covers the union of ASCII and JIS X 0208, and the UCS repertoire covered by the ASCII and JIS X 0208 mapping tables overlaps for one character, namely U+005C REVERSE SOLIDUS. EUC-JP converters therefore have to use a slightly modified JIS X 0208 mapping table, such that the JIS X 0208 code 0x2140 (0xA1 0xC0 in EUC-JP) gets mapped to U+FF3C FULLWIDTH REVERSE SOLIDUS. This way, round-trip compatibility from EUC-JP to Unicode to EUC-JP can be guaranteed without any loss of information." Markus -- Markus G. Kuhn, Computer Laboratory, University of Cambridge, UK Email: mkuhn at acm.org, WWW: <http://www.cl.cam.ac.uk/~mgk25/> _______________________________________________ I18n mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/i18n
