Dr Andrew Scott G7VAV

MBCS, MIET, Member ACM, Member IEEE

Senior Lecturer
School of Computing
and Communications

D35 InfoLab21
Lancaster University
Lancaster, LA1 4WA
United Kingdom

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MAPSCRN

Section: International Support (8)
Updated: 20 March 1993
Index Return to Main Contents

NAME

mapscrn - load screen output mapping table

SYNOPSIS

mapscrn [-v] [-o map.orig] mapfile

DESCRIPTION

The mapscrn command is obsolete - its function is now built-in into setfont. However, for backwards compatibility it is still available as a separate command.

The mapscrn command loads a user defined output character mapping table into the console driver. The console driver may be later put into use user-defined mapping table mode by outputting a special escape sequence to the console device. This sequence is <esc>(K for the G0 character set and <esc>)K for the G1 character set. When the -o option is given, the old map is saved in map.orig.

USE

There are two kinds of mapping tables: direct-to-font tables, that give a font position for each user byte value, and user-to-unicode tables that give a unicode value for each user byte. The corresponding glyph is now found using the unicode index of the font. The command

: mapscrn trivial

sets up a one-to-one direct-to-font table where user bytes directly address the font. This is useful for fonts that are in the same order as the character set one uses. A command like

: mapscrn 8859-2

sets up a user-to-unicode table that assumes that the user uses ISO 8859-2.

INPUT FORMAT

The mapscrn command can read the map in either of two formats:
1. 256 or 512 bytes binary data
2. two-column text file
Format (1) is a direct image of the translation table. The 256-bytes tables are direct-to-font, the 512-bytes tables are user-to-unicode tables. Format (2) is used to fill the table as follows: cell with offset mentioned in the first column is filled with the value mentioned in the second column. When values larger than 255 occur, or values are written using the U+xxxx notation, the table is assumed to be a user-to-unicode table, otherwise it is a direct-to-font table.

Values in the file may be specified in one of several formats:
1. Decimal: String of decimal digits not starting with '0'
2. Octal: String of octal digits beginning with '0'.
3. Hexadecimal: String of hexadecimal digits preceded by "0x".
4. Unicode: String of four hexadecimal digits preceded by "U+".
5. Character: Single character enclosed in single quotes. (And the binary value is used.) Note that blank, comma, tab character and '#' cannot be specified with this format.
6. UTF-8 Character: Single (possibly multi-byte) UTF-8 character, enclosed in single quotes.

Note that control characters (with codes < 32) cannot be re-mapped with mapscrn because they have special meaning for the driver.