unicode.rst (7232B)
1Unicode support 2=============== 3 4 Last update: 2005-01-17, version 1.4 5 6This file is maintained by H. Peter Anvin <unicode@lanana.org> as part 7of the Linux Assigned Names And Numbers Authority (LANANA) project. 8The current version can be found at: 9 10 http://www.lanana.org/docs/unicode/admin-guide/unicode.rst 11 12Introduction 13------------ 14 15The Linux kernel code has been rewritten to use Unicode to map 16characters to fonts. By downloading a single Unicode-to-font table, 17both the eight-bit character sets and UTF-8 mode are changed to use 18the font as indicated. 19 20This changes the semantics of the eight-bit character tables subtly. 21The four character tables are now: 22 23=============== =============================== ================ 24Map symbol Map name Escape code (G0) 25=============== =============================== ================ 26LAT1_MAP Latin-1 (ISO 8859-1) ESC ( B 27GRAF_MAP DEC VT100 pseudographics ESC ( 0 28IBMPC_MAP IBM code page 437 ESC ( U 29USER_MAP User defined ESC ( K 30=============== =============================== ================ 31 32In particular, ESC ( U is no longer "straight to font", since the font 33might be completely different than the IBM character set. This 34permits for example the use of block graphics even with a Latin-1 font 35loaded. 36 37Note that although these codes are similar to ISO 2022, neither the 38codes nor their uses match ISO 2022; Linux has two 8-bit codes (G0 and 39G1), whereas ISO 2022 has four 7-bit codes (G0-G3). 40 41In accordance with the Unicode standard/ISO 10646 the range U+F000 to 42U+F8FF has been reserved for OS-wide allocation (the Unicode Standard 43refers to this as a "Corporate Zone", since this is inaccurate for 44Linux we call it the "Linux Zone"). U+F000 was picked as the starting 45point since it lets the direct-mapping area start on a large power of 46two (in case 1024- or 2048-character fonts ever become necessary). 47This leaves U+E000 to U+EFFF as End User Zone. 48 49[v1.2]: The Unicodes range from U+F000 and up to U+F7FF have been 50hard-coded to map directly to the loaded font, bypassing the 51translation table. The user-defined map now defaults to U+F000 to 52U+F0FF, emulating the previous behaviour. In practice, this range 53might be shorter; for example, vgacon can only handle 256-character 54(U+F000..U+F0FF) or 512-character (U+F000..U+F1FF) fonts. 55 56 57Actual characters assigned in the Linux Zone 58-------------------------------------------- 59 60In addition, the following characters not present in Unicode 1.1.4 61have been defined; these are used by the DEC VT graphics map. [v1.2] 62THIS USE IS OBSOLETE AND SHOULD NO LONGER BE USED; PLEASE SEE BELOW. 63 64====== ====================================== 65U+F800 DEC VT GRAPHICS HORIZONTAL LINE SCAN 1 66U+F801 DEC VT GRAPHICS HORIZONTAL LINE SCAN 3 67U+F803 DEC VT GRAPHICS HORIZONTAL LINE SCAN 7 68U+F804 DEC VT GRAPHICS HORIZONTAL LINE SCAN 9 69====== ====================================== 70 71The DEC VT220 uses a 6x10 character matrix, and these characters form 72a smooth progression in the DEC VT graphics character set. I have 73omitted the scan 5 line, since it is also used as a block-graphics 74character, and hence has been coded as U+2500 FORMS LIGHT HORIZONTAL. 75 76[v1.3]: These characters have been officially added to Unicode 3.2.0; 77they are added at U+23BA, U+23BB, U+23BC, U+23BD. Linux now uses the 78new values. 79 80[v1.2]: The following characters have been added to represent common 81keyboard symbols that are unlikely to ever be added to Unicode proper 82since they are horribly vendor-specific. This, of course, is an 83excellent example of horrible design. 84 85====== ====================================== 86U+F810 KEYBOARD SYMBOL FLYING FLAG 87U+F811 KEYBOARD SYMBOL PULLDOWN MENU 88U+F812 KEYBOARD SYMBOL OPEN APPLE 89U+F813 KEYBOARD SYMBOL SOLID APPLE 90====== ====================================== 91 92Klingon language support 93------------------------ 94 95In 1996, Linux was the first operating system in the world to add 96support for the artificial language Klingon, created by Marc Okrand 97for the "Star Trek" television series. This encoding was later 98adopted by the ConScript Unicode Registry and proposed (but ultimately 99rejected) for inclusion in Unicode Plane 1. Thus, it remains as a 100Linux/CSUR private assignment in the Linux Zone. 101 102This encoding has been endorsed by the Klingon Language Institute. 103For more information, contact them at: 104 105 http://www.kli.org/ 106 107Since the characters in the beginning of the Linux CZ have been more 108of the dingbats/symbols/forms type and this is a language, I have 109located it at the end, on a 16-cell boundary in keeping with standard 110Unicode practice. 111 112.. note:: 113 114 This range is now officially managed by the ConScript Unicode 115 Registry. The normative reference is at: 116 117 https://www.evertype.com/standards/csur/klingon.html 118 119Klingon has an alphabet of 26 characters, a positional numeric writing 120system with 10 digits, and is written left-to-right, top-to-bottom. 121 122Several glyph forms for the Klingon alphabet have been proposed. 123However, since the set of symbols appear to be consistent throughout, 124with only the actual shapes being different, in keeping with standard 125Unicode practice these differences are considered font variants. 126 127====== ======================================================= 128U+F8D0 KLINGON LETTER A 129U+F8D1 KLINGON LETTER B 130U+F8D2 KLINGON LETTER CH 131U+F8D3 KLINGON LETTER D 132U+F8D4 KLINGON LETTER E 133U+F8D5 KLINGON LETTER GH 134U+F8D6 KLINGON LETTER H 135U+F8D7 KLINGON LETTER I 136U+F8D8 KLINGON LETTER J 137U+F8D9 KLINGON LETTER L 138U+F8DA KLINGON LETTER M 139U+F8DB KLINGON LETTER N 140U+F8DC KLINGON LETTER NG 141U+F8DD KLINGON LETTER O 142U+F8DE KLINGON LETTER P 143U+F8DF KLINGON LETTER Q 144 - Written <q> in standard Okrand Latin transliteration 145U+F8E0 KLINGON LETTER QH 146 - Written <Q> in standard Okrand Latin transliteration 147U+F8E1 KLINGON LETTER R 148U+F8E2 KLINGON LETTER S 149U+F8E3 KLINGON LETTER T 150U+F8E4 KLINGON LETTER TLH 151U+F8E5 KLINGON LETTER U 152U+F8E6 KLINGON LETTER V 153U+F8E7 KLINGON LETTER W 154U+F8E8 KLINGON LETTER Y 155U+F8E9 KLINGON LETTER GLOTTAL STOP 156 157U+F8F0 KLINGON DIGIT ZERO 158U+F8F1 KLINGON DIGIT ONE 159U+F8F2 KLINGON DIGIT TWO 160U+F8F3 KLINGON DIGIT THREE 161U+F8F4 KLINGON DIGIT FOUR 162U+F8F5 KLINGON DIGIT FIVE 163U+F8F6 KLINGON DIGIT SIX 164U+F8F7 KLINGON DIGIT SEVEN 165U+F8F8 KLINGON DIGIT EIGHT 166U+F8F9 KLINGON DIGIT NINE 167 168U+F8FD KLINGON COMMA 169U+F8FE KLINGON FULL STOP 170U+F8FF KLINGON SYMBOL FOR EMPIRE 171====== ======================================================= 172 173Other Fictional and Artificial Scripts 174-------------------------------------- 175 176Since the assignment of the Klingon Linux Unicode block, a registry of 177fictional and artificial scripts has been established by John Cowan 178<jcowan@reutershealth.com> and Michael Everson <everson@evertype.com>. 179The ConScript Unicode Registry is accessible at: 180 181 https://www.evertype.com/standards/csur/ 182 183The ranges used fall at the low end of the End User Zone and can hence 184not be normatively assigned, but it is recommended that people who 185wish to encode fictional scripts use these codes, in the interest of 186interoperability. For Klingon, CSUR has adopted the Linux encoding. 187The CSUR people are driving adding Tengwar and Cirth into Unicode 188Plane 1; the addition of Klingon to Unicode Plane 1 has been rejected 189and so the above encoding remains official.