On Tue, Jan 11, 2022 at 10:48 AM Clem Cole <clemc@ccc.com> wrote:
 
I do believe that you are correct that both the sources (and associated binaries) to original nroff/groff and ditroff were licensed and needed and an AT&T license, but not the documents themselves.

I assume you mean s/groff/troff/.  There must have been some public access to the documentation like this that allowed James Clark to develop groff in the 1987-91 time frame, though.  It's still the *roff shipped with *BSD.

dformat, a pic preprocessor by Jon Bentley that displays bits-in-a-word pictures, is now available at <https://github.com/arnoldrobbins/dformat>; it's written in awk.