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