1DITROFF(7) Miscellaneous Information Manual DITROFF(7)
2
3
4
6 ditroff - classical device independent roff
7
9 The name ditroff once marked a development level of the troff text pro‐
10 cessing system. In actual roff(7) systems, the name troff is used as a
11 synonym for ditroff.
12
13 The first roff system was written by Joe Ossanna around 1973. It sup‐
14 ported only two output devices, the nroff program produced text ori‐
15 ented tty output, while the troff program generated graphical output
16 for exactly one output device, the Wang Graphic Systems CAT typesetter.
17
18 In 1979, Brian Kernighan rewrote troff to support more devices by cre‐
19 ating an intermediate output format for troff that can be fed into
20 postprocessor programs which actually do the printout on the device.
21 Kernighan's version marks what is known as classical troff today. In
22 order to distinguish it from Ossanna's original mono-device version, it
23 was called ditroff (device independent troff) on some systems, though
24 this naming isn't mentioned in the classical documentation.
25
26 Today, any existing roff system is based on Kernighan's multi-device
27 troff. The distinction between troff and ditroff isn't necessary any
28 longer, for each modern troff provides already the complete functional‐
29 ity of ditroff. On most systems, the name troff is used to denote
30 ditroff.
31
32 The easiest way to use ditroff is the GNU roff system, groff. The
33 groff(1) program is a wrapper around (di)troff that automatically han‐
34 dles postprocessing.
35
37 [CSTR #54]
38 The 1992 revision of the Nroff/Troff User's Manual by J. F.
39 Ossanna and Brian Kernighan, see Bell Labs CSTR #54 ⟨http://
40 cm.bell-labs.com/cm/cs/cstr/54.ps.gz⟩.
41
42 [CSTR #97]
43 A Typesetter-independent TROFF by Brian Kernighan is the origi‐
44 nal documentation of the first multi-device troff (ditroff), see
45 Bell Labs CSTR #97 ⟨http://cm.bell-labs.com/cm/cs/cstr/
46 97.ps.gz⟩.
47
48 roff(7)
49 This document gives details on the history and concepts of roff.
50
51 troff(1)
52 The actual implementation of ditroff.
53
54 groff(1)
55 The GNU roff program and pointers to all documentation around
56 groff.
57
58 groff_out(5)
59 The groff version of the intermediate output language, the basis
60 for multi-devicing.
61
63 Copyright (C) 2001, 2002, 2004, 2007, 2008, 2009 Free Software Founda‐
64 tion, Inc.
65
66 This document is distributed under the terms of the FDL (GNU Free Docu‐
67 mentation License) version 1.3 or later. You should have received a
68 copy of the FDL on your system, it is also available on-line at the GNU
69 copyleft site ⟨http://www.gnu.org/copyleft/fdl.html⟩.
70
71 This document is part of groff, the GNU roff distribution. It was
72 written by Bernd Warken ⟨bwarken@mayn.de⟩ and is maintained by Werner
73 Lemberg ⟨wl@gnu.org⟩.
74
75
76
77Groff Version 1.20.1 9 January 2009 DITROFF(7)