patch-1.3.22 linux/drivers/char/README.unicode
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- Lines: 50
- Date:
Thu Jan 1 02:00:00 1970
- Orig file:
v1.3.21/linux/drivers/char/README.unicode
- Orig date:
Tue Jun 13 15:40:16 1995
diff -u --recursive --new-file v1.3.21/linux/drivers/char/README.unicode linux/drivers/char/README.unicode
@@ -1,49 +0,0 @@
-The Linux kernel code has been rewritten to use Unicode to map
-characters to fonts. By downloading a single Unicode-to-font table,
-both the eight-bit character sets and UTF-8 mode are changed to use
-the font as indicated.
-
-This changes the semantics of the eight-bit character tables subtly.
-The four character tables are now:
-
-Map symbol Map name Escape code (G0)
-
-LAT1_MAP Latin-1 (ISO 8859-1) ESC ( B
-GRAF_MAP DEC VT100 pseudographics ESC ( 0
-IBMPC_MAP IBM code page 437 ESC ( U
-USER_MAP User defined ESC ( K
-
-In particular, ESC ( U is no longer "straight to font", since the font
-might be completely different than the IBM character set. This
-permits for example the use of block graphics even with a Latin-1 font
-loaded.
-
-In accordance with the Unicode standard/ISO 10646 the range U+F000 to
-U+F8FF has been reserved for OS-wide allocation (the Unicode Standard
-refers to this as a "Corporate Zone"). U+F000 was picked as the
-starting point since it lets the direct-mapping area start on a large
-power of two (in case 1024- or 2048-character fonts ever become
-necessary). This leaves U+E000 to U+EFFF as End User Zone.
-
-The Unicodes in the range U+F000 to U+F1FF have been hard-coded to map
-directly to the loaded font, bypassing the translation table. The
-user-defined map now defaults to U+F000 to U+F1FF, emulating the
-previous behaviour.
-
-In addition, the following characters not present in Unicode 1.1.4 (at
-least, I have not found them!) have been defined; these are used by
-the DEC VT graphics map:
-
-U+F800 DEC VT GRAPHICS HORIZONTAL LINE SCAN 1
-U+F801 DEC VT GRAPHICS HORIZONTAL LINE SCAN 3
-U+F803 DEC VT GRAPHICS HORIZONTAL LINE SCAN 7
-U+F804 DEC VT GRAPHICS HORIZONTAL LINE SCAN 9
-
-The DEC VT220 uses a 6x10 character matrix, and these characters form
-a smooth progression in the DEC VT graphics character set. I have
-omitted the scan 5 line, since it is also used as a block-graphics
-character, and hence has been coded as U+2500 FORMS LIGHT HORIZONTAL.
-However, I left U+F802 blank should the need arise.
-
- H. Peter Anvin <[email protected]>
- Yggdrasil Computing, Inc.
FUNET's LINUX-ADM group, [email protected]
TCL-scripts by Sam Shen, [email protected]
with Sam's (original) version of this