.
The name
ditroff once marked a development level of the
troff text processing system.
.
In actual
roff(7) systems, the name
troff is used as a synonym for
ditroff . .
The first roff system was written by Joe Osanna around 1973.
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It supported only two output devices, the
nroff program produced text oriented tty output, while the
troff program generated graphical output for exactly one output device, the Wang
Graphic Systems CAT typesetter.
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In 1979, Brian Kernighan rewrote troff to support more devices by
creating an intermediate output format for troff that can be fed into
postprocessor programs which actually do the printout on the device.
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Kernighan's version marks what is known as
classical troff today.
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In order to distinguish it from Osanna's original mono-device version,
it was called
ditroff ( d/ evice~ i/ ndependent~ troff/ ) on some systems, though this naming isn't mentioned in the classical
documentation.
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Today, any existing roff system is based on Kernighan's multi-device
troff.
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The distinction between
troff and
ditroff isn't necessary any longer, for each modern
troff provides already the complete functionality of
ditroff . .
On most systems, the name
troff is used to denote
ditroff . .
The easiest way to use ditroff is the GNU roff system,
groff . The
groff(1) program is a wrapper around
(di)troff that automatically handles postprocessing.
.
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SEE ALSO
.
[CSTR~#54]
The 1992 revision of the
Nroff/Troff User's Manual by
J. F. Osanna and
"Brian Kernighan" , see
"Bell Labs CSTR~#54" .
.
[CSTR~#97]
A Typesetter-independent TROFF by
Brian Kernighan is the original documentation of the first multi-device troff
( ditroff/ ), see
"Bell Labs CSTR~#97" .
.
The groff version of the intermediate output language, the basis for
multi-devicing.
.
.
AUTHORS
.
Copyright (C) 2001, 2002 Free Software Foundation, Inc.
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This document is distributed under the terms of the FDL (GNU Free
Documentation License) version 1.1 or later.
.
You should have received a copy of the FDL on your system, it is also
available on-line at the
.
This document is part of
groff , the GNU roff distribution.
.
It was written by
and is maintained by
.
.