ditroff – classical device independent roff
once marked a development level of the
text processing system.
systems, the name
is used as a synonym for
The first roff system was written by Joe Osanna around 1973.
It supported only two output devices, the
program produced text oriented tty output, while the
program generated graphical output for exactly one output device, the Wang
Graphic Systems CAT
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.
Kernighan’s version marks what is known as
In order to distinguish it from Osanna’s original mono-device version,
it was called
on some systems, though this naming isn’t mentioned in the classical
Today, any existing roff system is based on Kernighan’s multi-device
The distinction between
isn’t necessary any longer, for each modern
provides already the complete functionality of
On most systems, the name
is used to denote
The easiest way to use ditroff is the GNU roff system,
program is a wrapper around
that automatically handles postprocessing.
J. F. Osanna
is the original documentation of the first multi-device troff
Copyright (C) 2001, 2002 Free Software Foundation, Inc.
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
the GNU roff distribution.
It was written by
and is maintained by