300(1) CLIX 300(1)
NAME
300, 300s - Handles special functions of DASI 300 and 300s terminals
SYNOPSIS
300 +12 -n
300s +12 -n
DESCRIPTION
The 300 command supports special functions and optimizes the use of the
DASI 300 (GSI 300 or DTC 300) terminal; 300s performs the same functions
for the DASI 300s (GSI 300s or DTC 300s) terminal. It converts half-line
forward, half-line reverse, and full-line reverse motions to the correct
vertical motions. In the following discussion of the 300 command, it
should be noted that unless your system contains AT&T Documenter's
Workbench software, references to certain commands (for example, nroff,
neqn, eqn, and so on) will not work. It attempts to draw Greek letters
and other special symbols. It permits convenient use of 12-pitch text.
It reduces printing time 5 to 70%. The 300 command can be used to print
equations neatly, in the sequence:
neqn file ... | nroff | 300
CAUTION: If your terminal has a PLOT switch, make sure it is turned on
before 300 is used.
The behavior of 300 can be modified by the following optional flag
arguments to handle 12-pitch text, fractional line spacings, messages, and
delays:
+12 Permits use of 12-pitch, 6 lines/inch text. DASI 300 terminals
normally allow only two combinations: 10-pitch, 6 lines/inch, or
12-pitch, 8 lines/inch. To obtain the 12-pitch, 6 lines per inch
combination, the user should turn the PITCH switch to 12, and use
the +12 flag.
-n Controls the size of half-line spacing. A half-line is, by
default, equal to 4 vertical plot increments. Because each
increment equals 1/48 of an inch, a 10-pitch linefeed requires 8
increments, while a 12-pitch linefeed needs only 6. The first
digit of n overrides the default value, thus allowing for
individual taste in the appearance of subscripts and superscripts.
For example, nroff half-lines could be made to act as quarter-lines
by using -2. The user could also obtain appropriate half-lines for
12-pitch, 8 lines/inch mode by using the flag -3 alone, having set
the PITCH switch to 12-pitch.
-dt,l,c
2/94 - Intergraph Corporation 1
300(1) CLIX 300(1)
Controls delay factors. The default setting is -d3,90,30. DASI
300 terminals sometimes produce peculiar output when faced with
very long lines, too many tab characters, or long strings of
blankless, nonidentical characters. One null (delay) character is
inserted in a line for every set of t tabs, and for every
contiguous string of c nonblank, nontab characters. If a line is
longer than l bytes, 1+(total length)/20 nulls are inserted at the
end of that line. Items can be omitted from the end of the list,
implying use of the default values. Also, a value of zero for t
(c) results in two null bytes per tab (character). The former may
be needed for C programs, the latter for files like /etc/passwd.
Because terminal behavior varies according to the specific
characters printed and the load on a system, the user may have to
experiment with these values to get correct output. The -d option
exists only as a last resort for those few cases that do not
otherwise print properly. For example, the file /etc/passwd may be
printed using -d3,30,5. The value -d0,1 is a good one to use for C
programs that have many levels of indentation.
Note that the delay control interacts heavily with the prevailing carriage
return and linefeed delays. The stty modes "nl0 cr2" or "nl0 cr3" are
recommended for most uses.
The 300 command can be used with the nroff -s flag or .rd requests, when
it is necessary to insert paper manually or change fonts in the middle of
a document. Instead of hitting the return key in these cases, you must
use the linefeed key to get any response.
In many (but not all) cases, the following sequences are equivalent:
nroff -T300 files
...
and nroff files
...
| 300
nroff -T300-12 files
...
and nroff files
...
| 300 +12
The use of 300 can thus often be avoided unless special delays or options
are required; in a few cases, however, the additional movement
optimization of 300 may produce better-aligned output.
EXAMPLES
1. To format input for a DASI 300 terminal using 12 pitch, 6 lines/inch,
2 Intergraph Corporation - 2/94
300(1) CLIX 300(1)
enter the following:
nroff | 300 +12
2. To format input for a DASI 300s terminal using quarter lines, enter
the following command:
nroff | 300s -2 -d2,60,20
This results in output formatted for a DASI 300s terminal. This
command also sets the delay factors.
NOTES
Some special characters cannot be correctly printed in column 1 because
the print head cannot be moved to the left from there.
If your output contains Greek and/or reverse linefeeds, use a friction-
feed platen instead of a forms tractor; although good enough for drafts,
the latter has a tendency to slip when reversing direction, distorting
Greek characters and misaligning the first line of text after one or more
reverse linefeeds.
EXIT VALUES
Exit values are not valid.
RELATED INFORMATION
Commands: mesg(1), graph(1), greek(1), stty(1), tabs(1), tplot(1) eqn(1),
450(1), nroff(1), tbl(1)
2/94 - Intergraph Corporation 3