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1Unicode support2===============3 4 Last update: 2005-01-17, version 1.45 6Note: The original version of this document, which was maintained at7lanana.org as part of the Linux Assigned Names And Numbers Authority8(LANANA) project, is no longer existent. So, this version in the9mainline Linux kernel is now the maintained main document.10 11Introduction12------------13 14The Linux kernel code has been rewritten to use Unicode to map15characters to fonts. By downloading a single Unicode-to-font table,16both the eight-bit character sets and UTF-8 mode are changed to use17the font as indicated.18 19This changes the semantics of the eight-bit character tables subtly.20The four character tables are now:21 22=============== =============================== ================23Map symbol Map name Escape code (G0)24=============== =============================== ================25LAT1_MAP Latin-1 (ISO 8859-1) ESC ( B26GRAF_MAP DEC VT100 pseudographics ESC ( 027IBMPC_MAP IBM code page 437 ESC ( U28USER_MAP User defined ESC ( K29=============== =============================== ================30 31In particular, ESC ( U is no longer "straight to font", since the font32might be completely different than the IBM character set. This33permits for example the use of block graphics even with a Latin-1 font34loaded.35 36Note that although these codes are similar to ISO 2022, neither the37codes nor their uses match ISO 2022; Linux has two 8-bit codes (G0 and38G1), whereas ISO 2022 has four 7-bit codes (G0-G3).39 40In accordance with the Unicode standard/ISO 10646 the range U+F000 to41U+F8FF has been reserved for OS-wide allocation (the Unicode Standard42refers to this as a "Corporate Zone", since this is inaccurate for43Linux we call it the "Linux Zone"). U+F000 was picked as the starting44point since it lets the direct-mapping area start on a large power of45two (in case 1024- or 2048-character fonts ever become necessary).46This leaves U+E000 to U+EFFF as End User Zone.47 48[v1.2]: The Unicodes range from U+F000 and up to U+F7FF have been49hard-coded to map directly to the loaded font, bypassing the50translation table. The user-defined map now defaults to U+F000 to51U+F0FF, emulating the previous behaviour. In practice, this range52might be shorter; for example, vgacon can only handle 256-character53(U+F000..U+F0FF) or 512-character (U+F000..U+F1FF) fonts.54 55 56Actual characters assigned in the Linux Zone57--------------------------------------------58 59In addition, the following characters not present in Unicode 1.1.460have been defined; these are used by the DEC VT graphics map. [v1.2]61THIS USE IS OBSOLETE AND SHOULD NO LONGER BE USED; PLEASE SEE BELOW.62 63====== ======================================64U+F800 DEC VT GRAPHICS HORIZONTAL LINE SCAN 165U+F801 DEC VT GRAPHICS HORIZONTAL LINE SCAN 366U+F803 DEC VT GRAPHICS HORIZONTAL LINE SCAN 767U+F804 DEC VT GRAPHICS HORIZONTAL LINE SCAN 968====== ======================================69 70The DEC VT220 uses a 6x10 character matrix, and these characters form71a smooth progression in the DEC VT graphics character set. I have72omitted the scan 5 line, since it is also used as a block-graphics73character, and hence has been coded as U+2500 FORMS LIGHT HORIZONTAL.74 75[v1.3]: These characters have been officially added to Unicode 3.2.0;76they are added at U+23BA, U+23BB, U+23BC, U+23BD. Linux now uses the77new values.78 79[v1.2]: The following characters have been added to represent common80keyboard symbols that are unlikely to ever be added to Unicode proper81since they are horribly vendor-specific. This, of course, is an82excellent example of horrible design.83 84====== ======================================85U+F810 KEYBOARD SYMBOL FLYING FLAG86U+F811 KEYBOARD SYMBOL PULLDOWN MENU87U+F812 KEYBOARD SYMBOL OPEN APPLE88U+F813 KEYBOARD SYMBOL SOLID APPLE89====== ======================================90 91Klingon language support92------------------------93 94In 1996, Linux was the first operating system in the world to add95support for the artificial language Klingon, created by Marc Okrand96for the "Star Trek" television series. This encoding was later97adopted by the ConScript Unicode Registry and proposed (but ultimately98rejected) for inclusion in Unicode Plane 1. Thus, it remains as a99Linux/CSUR private assignment in the Linux Zone.100 101This encoding has been endorsed by the Klingon Language Institute.102For more information, contact them at:103 104 http://www.kli.org/105 106Since the characters in the beginning of the Linux CZ have been more107of the dingbats/symbols/forms type and this is a language, I have108located it at the end, on a 16-cell boundary in keeping with standard109Unicode practice.110 111.. note::112 113 This range is now officially managed by the ConScript Unicode114 Registry. The normative reference is at:115 116 https://www.evertype.com/standards/csur/klingon.html117 118Klingon has an alphabet of 26 characters, a positional numeric writing119system with 10 digits, and is written left-to-right, top-to-bottom.120 121Several glyph forms for the Klingon alphabet have been proposed.122However, since the set of symbols appear to be consistent throughout,123with only the actual shapes being different, in keeping with standard124Unicode practice these differences are considered font variants.125 126====== =======================================================127U+F8D0 KLINGON LETTER A128U+F8D1 KLINGON LETTER B129U+F8D2 KLINGON LETTER CH130U+F8D3 KLINGON LETTER D131U+F8D4 KLINGON LETTER E132U+F8D5 KLINGON LETTER GH133U+F8D6 KLINGON LETTER H134U+F8D7 KLINGON LETTER I135U+F8D8 KLINGON LETTER J136U+F8D9 KLINGON LETTER L137U+F8DA KLINGON LETTER M138U+F8DB KLINGON LETTER N139U+F8DC KLINGON LETTER NG140U+F8DD KLINGON LETTER O141U+F8DE KLINGON LETTER P142U+F8DF KLINGON LETTER Q143 - Written <q> in standard Okrand Latin transliteration144U+F8E0 KLINGON LETTER QH145 - Written <Q> in standard Okrand Latin transliteration146U+F8E1 KLINGON LETTER R147U+F8E2 KLINGON LETTER S148U+F8E3 KLINGON LETTER T149U+F8E4 KLINGON LETTER TLH150U+F8E5 KLINGON LETTER U151U+F8E6 KLINGON LETTER V152U+F8E7 KLINGON LETTER W153U+F8E8 KLINGON LETTER Y154U+F8E9 KLINGON LETTER GLOTTAL STOP155 156U+F8F0 KLINGON DIGIT ZERO157U+F8F1 KLINGON DIGIT ONE158U+F8F2 KLINGON DIGIT TWO159U+F8F3 KLINGON DIGIT THREE160U+F8F4 KLINGON DIGIT FOUR161U+F8F5 KLINGON DIGIT FIVE162U+F8F6 KLINGON DIGIT SIX163U+F8F7 KLINGON DIGIT SEVEN164U+F8F8 KLINGON DIGIT EIGHT165U+F8F9 KLINGON DIGIT NINE166 167U+F8FD KLINGON COMMA168U+F8FE KLINGON FULL STOP169U+F8FF KLINGON SYMBOL FOR EMPIRE170====== =======================================================171 172Other Fictional and Artificial Scripts173--------------------------------------174 175Since the assignment of the Klingon Linux Unicode block, a registry of176fictional and artificial scripts has been established by John Cowan177<jcowan@reutershealth.com> and Michael Everson <everson@evertype.com>.178The ConScript Unicode Registry is accessible at:179 180 https://www.evertype.com/standards/csur/181 182The ranges used fall at the low end of the End User Zone and can hence183not be normatively assigned, but it is recommended that people who184wish to encode fictional scripts use these codes, in the interest of185interoperability. For Klingon, CSUR has adopted the Linux encoding.186The CSUR people are driving adding Tengwar and Cirth into Unicode187Plane 1; the addition of Klingon to Unicode Plane 1 has been rejected188and so the above encoding remains official.189