term.5

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· 5 代码 · 共 241 行

.\" SCCSID: @(#)term.5	8.1	9/11/90
.TH term 5 VAX
.SH Name
term \- terminal driving tables for nroff
.SH Description
.NXR "term file" "format"
.NXAM "nroff text processor" "term file"
The 
.MS nroff 1
command
uses driving tables to customize its output for various types of
output devices.  
These driving tables are written
as C programs, compiled, and installed in
\f(CW/usr/lib/term/tab\fIname\fR,
where
.I name
is the name for that terminal type as given in 
.MS term 7 .
The structure of the tables is as follows:
.EX
#define	INCH	240
struct {
	int bset;
	int breset;
	int Hor;
	int Vert;
	int Newline;
	int Char;
	int Em;
	int Halfline;
	int Adj;
	char *twinit;
	char *twrest;
	char *twnl;
	char *hlr;
	char *hlf;
	char *flr;
	char *bdon;
	char *bdoff;
	char *ploton;
	char *plotoff;
	char *up;
	char *down;
	char *right;
	char *left;
	char *codetab[256\-32];
	char *zzz;
} t;
.EE
.PP
The meanings of the various fields are:
.NXR "term file" "field definitions"
.TP 10
.I bset\^
Bits to set in the
.I c_oflag\^
field of the
.PN termio\^
structure
before output.
For further information, see
.MS tty 4 .
.TP 10
.I breset\^
Bits to reset in the
.I c_oflag\^
field of the
.PN termio\^
structure
before output.
.TP 10
.I Hor\^
Horizontal resolution in fractions of an inch.
.TP 10
.I Vert\^
Vertical resolution in fractions of an inch.
.TP 10
.I Newline\^
Space moved by a newline (linefeed) character in fractions
of an inch.
.TP 10
.I Char\^
Quantum of character sizes, in fractions of an inch
(that is, a character is a multiple of Char units wide).
.TP 10
.I Em\^
Size of an em in fractions of an inch.
.TP 10
.I Halfline\^
Space moved by a half-linefeed (or half-reverse-linefeed)
character in fractions of an inch.
.TP 10
.I Adj\^
Quantum of white space, in fractions of an inch
(that is, white spaces are a multiple of Adj units wide).
.IP
Note: if this is less than the size of the space
character (in units of Char; see the following 
fields for how the sizes of characters are defined),
.PN nroff\^
outputs
fractional spaces using plot mode.  Also, if the
.PN \-e
option to
.PN nroff
is used, 
.PN nroff 
sets Adj equal to Hor.
.TP 10
.I twinit\^
Set of characters used to initialize the terminal
in a mode suitable for
.PN nroff .
.TP 10
.I twrest\^
Set of characters used to restore the terminal to
normal mode.
.TP 10
.I twnl\^
Set of characters used to move down one line.
.TP 10
.I hlr\^
Set of characters used to move up one-half line.
.TP 10
.I hlf\^
Set of characters used to move down one-half line.
.TP 10
.I flr\^
Set of characters used to move up one line.
.TP 10
.I bdon\^
Set of characters used to turn on hardware boldface mode,
if any.
.TP 10
.I bdoff\^
Set of characters used to turn off hardware boldface mode,
if any.
.TP 10
.I iton\^
Set of characters used to turn on hardware italics mode,
if any.
.TP 10
.I itoff\^
Set of characters used to turn off hardware italics mode,
if any.
.TP 10
.I ploton\^
Set of characters used to turn on hardware plot mode
(for Diablo type mechanisms), if any.
.TP 10
.I plotoff\^
Set of characters used to turn off hardware plot mode
(for Diablo type mechanisms), if any.
.TP 10
.I up\^
Set of characters used to move up one resolution unit
(Vert) in plot mode, if any.
.TP 10
.I down\^
Set of characters used to move down one resolution unit
(Vert) in plot mode, if any.
.TP 10
.I right\^
Set of characters used to move right one resolution unit
(Hor) in plot mode, if any.
.TP 10
.I left\^
Set of characters used to move left one resolution unit
(Hor) in plot mode, if any.
.TP 10
.I codetab\^
Definition of characters needed to print an
.PN nroff\^
character
on the terminal.
The first byte is the number of
character units (Char) needed to hold the
character; that is, ``\\001'' is one unit wide, ``\\002'' is two
units wide, and so on.  The high-order bit (0200) is on if
the character is to be underlined in underline mode
(.ul).
The rest of the bytes are the characters
used to produce the character in
question.  If the character has the sign (0200) bit on,
it is a code to move the terminal in plot mode.  It is
encoded as:
.RS
.IP "0100 bit on" 15
Vertical motion
.IP "0100 bit off" 15
Horizontal motion
.IP "040 bit on" 15
Negative (up or left) motion
.IP "040 bit off" 15
Positive (down or right) motion
.IP "037 bits" 15
Number of such motions to make
.RE
.TP 10
.I zzz\^
A zero terminator at the end
.PP
All quantities that are in units of fractions of an inch should
be expressed as
.RI INCH* num / denom ,
where
.I num\^
and
.I denom\^
are respectively the numerator and denominator of the fraction; that is, 
1/48 of an inch would be written as ``INCH1/48''.
.PP
If any sequence of characters does not pertain to the output device,
that sequence should be given as a null string.
.PP
The source code for the terminal
.I name\^
is in 
\f(CW/usr/src/usr.bin/nroff/term/tab\fIname\fR.
When a new terminal type is added, the file 
.PN maketerms.c
should be updated to include the source to that driving table (use #include).
Note that the various terminal types are grouped into ``parts'' labelled
PART1, PART2, and PART3.
If necessary, more parts can be added.  Users can make other changes to
.PN maketerms.c 
as needed.
The makefile 
.PN terms.mk
in that directory should then be updated.
.SH Files
.TP 25
\f(CW/usr/lib/term/tab\fIname\fP
Driving tables
.TP
\f(CWtab\fIname\fP.c
Source for driving tables
.SH See Also
tty(4), term(7)