.ig
ditroff.man

Last update: 2 Jul 2004

This file is part of groff, the GNU roff type-setting system.

Copyright (C) 2001, 2002, 2004 Free Software Foundation, Inc.
written by Bernd Warken <bwarken@mayn.de>
maintained by Werner Lemberg <wl@gnu.org>

Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.1 or
any later version published by the Free Software Foundation; with the
Invariant Sections being this .ig-section and AUTHORS, with no
Front-Cover Texts, and with no Back-Cover Texts.

A copy of the Free Documentation License is included as a file called
FDL in the main directory of the groff source package.
..
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.\" --------------------------------------------------------------------
.\" Title
.\" --------------------------------------------------------------------
.
.TH DITROFF @MAN7EXT@ "@MDATE@" "Groff Version @VERSION@"
.SH NAME
ditroff \- classical device independent roff
.
.
.\" --------------------------------------------------------------------
.SH DESCRIPTION
.\" --------------------------------------------------------------------
.
The name
.I ditroff
once marked a development level of the
.I troff
text processing system.
.
In actual
.BR roff (@MAN7EXT@)
systems, the name
.I troff
is used as a synonym for
.IR ditroff .
.
.P
The first roff system was written by Joe Osanna around 1973.
.
It supported only two output devices, the
.B nroff
program produced text oriented tty output, while the
.B troff
program generated graphical output for exactly one output device, the Wang
.I Graphic Systems CAT
typesetter.
.
.P
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 
.I classical troff
today.
.
In order to distinguish it from Osanna's original mono-device version,
it was called
.I ditroff
(\c
.IR d\/ evice\~ i\/ ndependent\~ troff\/\c
)
on some systems, though this naming isn't mentioned in the classical
documentation.
.
.P
Today, any existing roff system is based on Kernighan's multi-device
troff.
.
The distinction between
.I troff
and 
.I ditroff
isn't necessary any longer, for each modern
.I troff
provides already the complete functionality of
.IR ditroff .
.
On most systems, the name
.I troff
is used to denote
.IR ditroff .
.
.P
The easiest way to use ditroff is the GNU roff system,
.IR groff .
The
.BR groff (@MAN1EXT@)
program is a wrapper around
.I (di)troff
that automatically handles postprocessing.
.
.
.\" --------------------------------------------------------------------
.SH "SEE ALSO"
.\" --------------------------------------------------------------------
.
.TP
.I [CSTR\~#54]
The 1992 revision of the
.I Nroff/Troff User's Manual
by
.I J. F. Osanna
and
.IR "Brian Kernighan" ,
see
.br
.URL http://\:cm.bell-labs.com/\:cm/\:cs/\:cstr/\:54.ps.gz \
     "Bell Labs CSTR\~#54" .
.
.TP
.I [CSTR\~#97]
.I A Typesetter-independent TROFF
by
.I Brian Kernighan
is the original documentation of the first multi-device troff
.RI ( ditroff\/ ),
see
.br
.URL http://\:cm.bell-labs.com/\:cm/\:cs/\:cstr/\:97.ps.gz \
     "Bell Labs CSTR\~#97" .
.
.TP
.BR roff (@MAN7EXT@)
This document gives details on the history and concepts of roff.
.
.TP
.BR @g@troff (@MAN1EXT@)
The actual implementation of
.IR ditroff .
.
.TP
.BR groff (@MAN1EXT@)
The GNU roff program and pointers to all documentation around groff.
.
.TP
.BR groff_out (@MAN5EXT@)
The groff version of the intermediate output language, the basis for
multi-devicing.
.
.
.\" --------------------------------------------------------------------
.SH "AUTHORS"
.\" --------------------------------------------------------------------
.
Copyright (C) 2001, 2002, 2004 Free Software Foundation, Inc.
.
.P
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
.URL http://\:www.gnu.org/\:copyleft/\:fdl.html "GNU copyleft site" .
.
.P
This document is part of
.IR groff ,
the GNU roff distribution.
.
It was written by
.MTO bwarken@mayn.de "Bernd Warken"
and is maintained by
.MTO wl@gnu.org "Werner Lemberg" .
.
.
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