To fill out the historical record, the earliest doctype I know of was a shell (not rc) script. From my basement heater that happens to run 10/e: b$ man doctype | uniq DOCTYPE(1) DOCTYPE(1) NAME doctype - guess command line for formatting a document SYNOPSIS doctype [ option ... ] [ file ] DESCRIPTION Doctype guesses and prints on the standard output the com- mand line for printing a document that uses troff(1), related preprocessors like eqn(1), and the ms(6) and mm macro packages. Option -n invokes nroff instead of troff. Other options are passed to troff. EXAMPLES eval `doctype chapter.?` | apsend Typeset files named chapter.0, chapter.1, ... SEE ALSO troff(1), eqn(1), tbl(1), refer(1), prefer(1), pic(1), ideal(1), grap(1), ped(9.1), mcs(6), ms(6), man(6) BUGS It's pretty dumb about guessing the proper macro package. Page 1 Tenth Edition (printed 2/24/2021) doctype(1) is in the 8/e manual, so it existed in early 1985; I bet it's actually older than that. The manual page is on the V8 tape, but, oddly, not the program; neither is it in the V10 pseudo-tape I cobbled together for Warren long ago. I'm not sure why not. The version in rc is, of course, a B-movie remake of the original. Norman Wilson Toronto ON