[Groff] troff source code

[Mark Lawrence]

Caldera has released (under a Berkeley-style license) the source code
for a variety of old Unices. This includes the sources for troff and
friends. They can be found at

http://www.tuhs.org/Archive/PDP-11/Distributions/research/

which gives Version 3 through Version 7, and

http://www.tuhs.org/Archive/PDP-11/Distributions/usdl/

which gives 32V. The details of the Caldera's license are in the PDF
file

http://www.tuhs.org/Archive/Caldera-license.pdf

These might be good way to investigate the "how did the original troff do
it?" questions that occasionally arise. (Then again, maybe
not--ditroff was a relative latecomer. Does anyone have a C/A/T
phototypesetter?) At any rate, I think it's worth inclusion in the
source code page of troff.org.

--
Mark Lawrence
www.unified-eng.com