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Based on kernel version 4.16.1. Page generated on 2018-04-09 11:52 EST.

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