On Mon, Dec 1, 2014 at 10:46 AM, Warner Losh <imp@bsdimp.com> wrote:

I remember playing ZORK (dungeo) in college on a VAX 11/750 which was
a PDP-11 a.out run in emulation mode (well, to be honest it was even more
complex than that, since there was a shell script to open all the data files on
specific FDs, setup some weird environment variables and then the PDP-11
program was run). The image looked to be converted from an RT-11 version
of the program that I ran under RSTS/E on a PDP-11/34 while working for a
small database company in high school…

I’d always wondered how that came to be, and what tools were needed to
run it...

Ah the "dmap" talk from the guys at Pitt in I think the winter 1980 USENIX conference.

The story is that it was indeed an RT11 image. The guys at Pitt hacked up "enough" support for the 11 emulation mode on 4.1 to allow it to run. The project was referred to as "dmap manipulation" to keep it under the radar. I can picture the face of the guy that did it, but I've forgotten his name. I fear it was early enough in USENIX time that there might not be proceedings.

Clem