MFC r363408:
r363408 | imp | 2020-07-21 18:44:47 -0600 (Tue, 21 Jul 2020) | 4 lines

getty appears to date from 3rd edition research unix. That's the oldest man page
on TUHS and its 'unix 1972' restoration effort has assembler sources that look
like simpler version of what's in the 5th edition.