PC DOS 1.0, but not quite

Astute readers will notice that that's exactly the same message as PC DOS 1.0 (August 1981) shows, but this COMMAND.COM did not prompt for the date. That's because this disk is not from August but rather early June 1981 - newest file is timestamped June 6, 1981 - which may make it the oldest known surviving piece of software written for the IBM PC (not counting the IBM PC ROMs which are dated April 1981). Itis certainly the oldest known surviving PC operating system.I'm starting to sound like a broken record on this topic, but it can't be said often enough: the preservation of software - whether important world-changing or not - is crucial if we want to document the history of where software came from, and where it's going to.