ditroff(7) — Linux manual page

Name \| Description \| Authors \| See also \| COLOPHON

ditroff(7)           Miscellaneous Information Manual          ditroff(7)

Name top

       ditroff - device-independent typesetter roff

Description top

       The name ditroff refers to a historical development stage of the
       roff(7) text processing system.  In roff systems extant today, the
       name troff is a synonym for ditroff.

       Early versions of roff by Joe Ossanna generated two programs from
       the same sources, using conditional compilation to distinguish
       them.  nroff produced text-oriented TTY output, while troff
       generated graphical output for exactly one output device, the Wang
       Graphic Systems CAT phototypesetter.

       In 1979, Brian Kernighan rewrote troff to support more devices by
       creating an intermediate output format for troff that could be fed
       into postprocessor programs which actually do the printout on the
       device.  Kernighan's version marks what is known as “classical
       troff” today.  In order to distinguish it from Ossanna's original
       version, it was called ditroff (device independent troff) on some
       systems, though this naming isn't mentioned in the classical
       documentation.

       Today, all existing roff systems are based on Kernighan's multi-
       device troff.  The distinction between troff and ditroff is no
       longer necessary; each modern troff provides the complete
       functionality of ditroff.

       The easiest way to use ditroff is via the GNU roff system, groff.
       The groff(1) program is a wrapper around (di)troff that
       automatically handles device postprocessing.

Authors top

       This document was written by Bernd Warken ⟨groff-bernd.warken-72@
       web.de⟩.

See also top

       CSTR #54
              refers to the 1992 revision of the Nroff/Troff User's
              Manual by J. F. Ossanna and Brian Kernighan.

       CSTR #97
              refers to A Typesetter-independent TROFF, by Brian
              Kernighan and is the original documentation of the first
              multi-device troff (ditroff).

       roff(7)
              provides a history and conceptual overview of roff systems.

       troff(1)
              describes the GNU implementation of (di)troff.

       groff(1)
              documents the GNU roff program and includes pointers to
              further documentation about groff.

       groff_out(5)
              describes the groff version of the intermediate output
              language, the basis for multi-device output.

COLOPHON top

       This page is part of the groff (GNU troff) project.  Information
       about the project can be found at 
       ⟨http://www.gnu.org/software/groff/⟩.  If you have a bug report for
       this manual page, see ⟨http://www.gnu.org/software/groff/⟩.  This
       page was obtained from the project's upstream Git repository
       ⟨https://git.savannah.gnu.org/git/groff.git⟩ on 2025-08-11.  (At
       that time, the date of the most recent commit that was found in
       the repository was 2025-08-09.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there is
       a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       [email protected]

groff 1.23.0.rc1.1931-35c9b  30 January 2022                   ditroff(7)