Unicode support=============== 		 Last update: 2005-01-17, version 1.4 Note: The original version of this document, which was maintained atlanana.org as part of the Linux Assigned Names And Numbers Authority(LANANA) project, is no longer existent.  So, this version in themainline Linux kernel is now the maintained main document. Introduction------------ The Linux kernel code has been rewritten to use Unicode to mapcharacters to fonts.  By downloading a single Unicode-to-font table,both the eight-bit character sets and UTF-8 mode are changed to usethe font as indicated. This changes the semantics of the eight-bit character tables subtly.The four character tables are now: =============== =============================== ================Map symbol	Map name			Escape code (G0)=============== =============================== ================LAT1_MAP	Latin-1 (ISO 8859-1)		ESC ( BGRAF_MAP	DEC VT100 pseudographics	ESC ( 0IBMPC_MAP	IBM code page 437		ESC ( UUSER_MAP	User defined			ESC ( K=============== =============================== ================ In particular, ESC ( U is no longer "straight to font", since the fontmight be completely different than the IBM character set.  Thispermits for example the use of block graphics even with a Latin-1 fontloaded. Note that although these codes are similar to ISO 2022, neither thecodes nor their uses match ISO 2022; Linux has two 8-bit codes (G0 andG1), whereas ISO 2022 has four 7-bit codes (G0-G3). In accordance with the Unicode standard/ISO 10646 the range U+F000 toU+F8FF has been reserved for OS-wide allocation (the Unicode Standardrefers to this as a "Corporate Zone", since this is inaccurate forLinux we call it the "Linux Zone").  U+F000 was picked as the startingpoint since it lets the direct-mapping area start on a large power oftwo (in case 1024- or 2048-character fonts ever become necessary).This leaves U+E000 to U+EFFF as End User Zone. [v1.2]: The Unicodes range from U+F000 and up to U+F7FF have beenhard-coded to map directly to the loaded font, bypassing thetranslation table.  The user-defined map now defaults to U+F000 toU+F0FF, emulating the previous behaviour.  In practice, this rangemight be shorter; for example, vgacon can only handle 256-character(U+F000..U+F0FF) or 512-character (U+F000..U+F1FF) fonts.  Actual characters assigned in the Linux Zone-------------------------------------------- In addition, the following characters not present in Unicode 1.1.4have been defined; these are used by the DEC VT graphics map.  [v1.2]THIS USE IS OBSOLETE AND SHOULD NO LONGER BE USED; PLEASE SEE BELOW. ====== ======================================U+F800 DEC VT GRAPHICS HORIZONTAL LINE SCAN 1U+F801 DEC VT GRAPHICS HORIZONTAL LINE SCAN 3U+F803 DEC VT GRAPHICS HORIZONTAL LINE SCAN 7U+F804 DEC VT GRAPHICS HORIZONTAL LINE SCAN 9====== ====================================== The DEC VT220 uses a 6x10 character matrix, and these characters forma smooth progression in the DEC VT graphics character set.  I haveomitted the scan 5 line, since it is also used as a block-graphicscharacter, and hence has been coded as U+2500 FORMS LIGHT HORIZONTAL. [v1.3]: These characters have been officially added to Unicode 3.2.0;they are added at U+23BA, U+23BB, U+23BC, U+23BD.  Linux now uses thenew values. [v1.2]: The following characters have been added to represent commonkeyboard symbols that are unlikely to ever be added to Unicode propersince they are horribly vendor-specific.  This, of course, is anexcellent example of horrible design. ====== ======================================U+F810 KEYBOARD SYMBOL FLYING FLAGU+F811 KEYBOARD SYMBOL PULLDOWN MENUU+F812 KEYBOARD SYMBOL OPEN APPLEU+F813 KEYBOARD SYMBOL SOLID APPLE====== ====================================== Klingon language support------------------------ In 1996, Linux was the first operating system in the world to addsupport for the artificial language Klingon, created by Marc Okrandfor the "Star Trek" television series.	This encoding was lateradopted by the ConScript Unicode Registry and proposed (but ultimatelyrejected) for inclusion in Unicode Plane 1.  Thus, it remains as aLinux/CSUR private assignment in the Linux Zone. This encoding has been endorsed by the Klingon Language Institute.For more information, contact them at: 	http://www.kli.org/ Since the characters in the beginning of the Linux CZ have been moreof the dingbats/symbols/forms type and this is a language, I havelocated it at the end, on a 16-cell boundary in keeping with standardUnicode practice. .. note::   This range is now officially managed by the ConScript Unicode  Registry.  The normative reference is at: 	https://www.evertype.com/standards/csur/klingon.html Klingon has an alphabet of 26 characters, a positional numeric writingsystem with 10 digits, and is written left-to-right, top-to-bottom. Several glyph forms for the Klingon alphabet have been proposed.However, since the set of symbols appear to be consistent throughout,with only the actual shapes being different, in keeping with standardUnicode practice these differences are considered font variants. ======	=======================================================U+F8D0	KLINGON LETTER AU+F8D1	KLINGON LETTER BU+F8D2	KLINGON LETTER CHU+F8D3	KLINGON LETTER DU+F8D4	KLINGON LETTER EU+F8D5	KLINGON LETTER GHU+F8D6	KLINGON LETTER HU+F8D7	KLINGON LETTER IU+F8D8	KLINGON LETTER JU+F8D9	KLINGON LETTER LU+F8DA	KLINGON LETTER MU+F8DB	KLINGON LETTER NU+F8DC	KLINGON LETTER NGU+F8DD	KLINGON LETTER OU+F8DE	KLINGON LETTER PU+F8DF	KLINGON LETTER Q	- Written <q> in standard Okrand Latin transliterationU+F8E0	KLINGON LETTER QH	- Written <Q> in standard Okrand Latin transliterationU+F8E1	KLINGON LETTER RU+F8E2	KLINGON LETTER SU+F8E3	KLINGON LETTER TU+F8E4	KLINGON LETTER TLHU+F8E5	KLINGON LETTER UU+F8E6	KLINGON LETTER VU+F8E7	KLINGON LETTER WU+F8E8	KLINGON LETTER YU+F8E9	KLINGON LETTER GLOTTAL STOP U+F8F0	KLINGON DIGIT ZEROU+F8F1	KLINGON DIGIT ONEU+F8F2	KLINGON DIGIT TWOU+F8F3	KLINGON DIGIT THREEU+F8F4	KLINGON DIGIT FOURU+F8F5	KLINGON DIGIT FIVEU+F8F6	KLINGON DIGIT SIXU+F8F7	KLINGON DIGIT SEVENU+F8F8	KLINGON DIGIT EIGHTU+F8F9	KLINGON DIGIT NINE U+F8FD	KLINGON COMMAU+F8FE	KLINGON FULL STOPU+F8FF	KLINGON SYMBOL FOR EMPIRE======	======================================================= Other Fictional and Artificial Scripts-------------------------------------- Since the assignment of the Klingon Linux Unicode block, a registry offictional and artificial scripts has been established by John Cowan<jcowan@reutershealth.com> and Michael Everson <everson@evertype.com>.The ConScript Unicode Registry is accessible at: 	  https://www.evertype.com/standards/csur/ The ranges used fall at the low end of the End User Zone and can hencenot be normatively assigned, but it is recommended that people whowish to encode fictional scripts use these codes, in the interest ofinteroperability.  For Klingon, CSUR has adopted the Linux encoding.The CSUR people are driving adding Tengwar and Cirth into UnicodePlane 1; the addition of Klingon to Unicode Plane 1 has been rejectedand so the above encoding remains official.