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