The last line in the man pages contains an OS version and a date. I have
failed to find any pattern in those lines, for example

  ls(1)         4.4BSD                           July 29, 1994
  ldd(1)        NetBSD                           October 22, 1993
  colrm(1)      3rd Berkeley Distribution        June 6, 1993
  domainname(1) 4.2 Berkeley Distribution        May 31, 1993

Just curious what they mean...

   /Krister