411 REFERENCE · Wikibooks
Guide to Unix/Commands/roff
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
roff was a predecessor of troff and nroff typesetting or formatting command-line tools. These tools are noted by their use by the man command. They do not seem to be covered by POSIX.
groff is a GNU's free replacement for troff and nroff.
Links
troff manual page, man.cat-v.org
groff(1) manual page, freebsd.org
roff(7) manual page, freebsd.org
GNU Troff (Groff) Manuals Online, gnu.org
The Text Processor for Typesetters, troff.org
troff/nroff quick reference, quut.com
W:Roff (computer program)
W:Troff
W:Nroff
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