TERM(F) UNIX System V
Name
term - terminal driving tables for nroff
Description
nroff(CT) uses driving tables to customize its output for
various types of output devices, such as printing terminals,
special word-processing printers (such as Diablo, Qume, or
NEC Spinwriter mechanisms), or special output filter
programs. These driving tables are written as C programs,
compiled, and installed in /usr/lib/term/tabname, where name
is the name for that terminal type as shown in term(CT).
The structure of the tables is as follows. Sizes are in
240ths of an inch.
#define INCH 240
#include /usr/lib/term/terms.h
struct termtable tlp ; { \* lp is the name of the term, *\
int bset; \* modify with new name, such as tnew *\
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 *iton;
char *itoff;
char *ploton;
char *plotoff;
char *up;
char *down;
char *right;
char *left;
char *codetab[256-32];
char *zzz;
} ;
The meanings of the various fields are as follows:
bset bits to set in termio.c_oflag see tty(M) and
termio(M)). after output.
breset bits to reset in termio.c_oflag before output.
Hor horizontal resolution in fractions of an inch.
Vert vertical resolution in fractions of an inch.
Newline space moved by a newline (linefeed) character in
fractions of an inch.
Char quantum of character sizes, in fractions of an
inch. (i.e., characters are multiples of Char
units wide. See codetab below.)
Em size of an em in fractions of an inch.
Halfline space moved by a half-linefeed (or half-reverse-
linefeed) character in fractions of an inch.
Adj quantum of white space for margin adjustment in
the absence of the -e option, in fractions of an
inch. (i.e., white spaces are a multiple of Adj
units wide)
Note: if this is less than the size of the space
character (in units of Char; see below for how the
sizes of characters are defined), nroff will
output fractional spaces using plot mode. Also,
if the -e switch to nroff is used, Adj is set
equal to Hor by nroff.
twinit set of characters used to initialize the terminal
in a mode suitable for nroff.
twrest set of characters used to restore the terminal to
normal mode.
twnl set of characters used to move down one line.
hlr set of characters used to move up one-half line.
hlf set of characters used to move down one-half line.
flr set of characters used to move up one line.
bdon set of characters used to turn on hardware
boldface mode, if any. Nroff assumes that
boldface mode is reset automatically by the twnl
string, because many letter-quality printers reset
the boldface mode when they receive a carriage
return; the twnl string should include whatever
characters are necessary to reset the boldface
mode.
bdoff set of characters used to turn off hardware
boldface mode, if any.
iton set of characters used to turn on hardware italics
mode, if any.
itoff set of characters used to turn off hardware
italics mode, if any.
ploton set of characters used to turn on hardware plot
mode (for Diablo-type mechanisms), if any.
plotoff set of characters used to turn off hardware plot
mode (for Diablo-type mechanisms), if any.
up set of characters used to move up one resolution
unit (Vert) in plot mode, if any.
down set of characters used to move down one resolution
unit (Vert) in plot mode, if any.
right set of characters used to move right one
resolution unit (Hor) in plot mode, if any.
left set of characters used to move left one resolution
unit (Hor) in plot mode, if any.
codetab Array of sequences to print individual characters.
Order is nroff's internal ordering. See the file
/usr/lib/term/tabuser.c for the exact order.
zzz a zero terminator at the end.
The codetab sequences each begin with a flag byte. The top
bit indicates whether the sequence should be underlined in
the .ul font. The rest of the byte is the width of the
sequence in units of Char.
The remainder of each codetab sequence is a sequence of
characters to be output. Characters with the top bit off
are output as given; characters with the top bit on
indicate escape into plot mode. When such an escape
character is encountered, nroff shifts into plot mode,
emitting ploton, and skips to the next character if the
escape character was '\200'.
When in plot mode, characters with the top bit off are
output as given. A character with the top bit on indicates
a motion. The next bit indicates coordinate, with 1 being
vertical and 0 being horizontal.
The next bit indicates direction, with 1 meaning up or left.
The remaining five bits give the amount of the motion. An
amount of zero causes exit from plot mode.
When plot mode is exited, either at the end of the string or
via the amount-zero exit, plotoff is emitted followed by a
blank.
All quantities which are in units of fractions of an inch
should be expressed as INCH*num/denom, where num and denom
are respectively the numerator and denominator of the
fraction; that is, 1/48 of an inch would be written as
``INCH/48''.
If any sequence of characters does not pertain to the output
device, that sequence should be given as a null string.
The Development System must be installed on the computer to
create a new driving table. The source code for a generic
output device is in the file /usr/lib/term/tabuser.c Copy
this file and make the necessary modifications, including
the name of the termtable struct. Refer to the hardware
manual for the codes needed for the output device (terminal,
printer, etc.). Name the file according to the convention
explained in term(CT). The makefile,
/usr/lib/term/makefile, should be updated to include the
source file to the new driving table. To perform the
modification, enter the command:
cc -M3e -O -c tabuser.c maketerm.o -o maketerm
When the files are prepared, enter the command :
make
(See make(CP)). The source to the new driving table is
linked with the object file mkterm.o, and the new driving
table is created and installed in the proper directory.
Files
/usr/lib/term/tabname driving tables
/usr/lib/term/tabuser.cgeneric source for driving tables
/usr/lib/term/makefile makefile for creating driving tables
/usr/lib/term/mkterm.o linkable object file for creating driving tables
/usr/lib/term/terms.h used to create nroff driving tables
See Also
nroff(CT), term(CT)
Notes
The Development System and text processing software must be
installed on the computer to create new driving tables.
Not all UNIX facilities support all of these options.
(printed 8/23/89) TERM(F)