On Mon, Apr 6, 2020 at 5:00 PM Dennis Boone <drb@msu.edu> wrote:

> The tape was made by a PDP-11 system running RT-11.  This manual may
> help a little:
>
>
> http://bitsavers.org/pdf/dec/pdp11/rt11/v5.6_Aug91/AA-PD6PA-TC_RT-11_Volume_and_File_Formats_Manual_Aug91.pdf
>
> TL;DR - This tape was written by just copying disk files to it, so the
> files which contain actual data are just images of the disk files.
>
> File 2 is a V6 image that's bootable like so

%pdp11
sim> set cpu 11/45
sim> att rk0 2.tape
sim> boot rk0
@rkunnix

login:

File 5 - this looks like a file system image.
>

It's the rest of the sources from the last disk. You can mount it like so
if you add a 'att rk1 5.tape' to the above

# mkdir /rk1
# /etc/mount /dev/rk1 /rk1


> File 8 - appears to be some sort of archiver output, but while the .ARC
> extension might lead you to suspect the old CP/M - MSDOS ARC program was
> responsible, that doesn't appear to be the case.
>

You'd think that from the name, but you can mount it also like the above.
With the 'att rk2 8.tape' and 'att rk3 11.tape'

# chdir /dev
# /etc/mknod rk2 b 0 2
# /etc/mknod rk3 b 0 3
# mkdir /rk2 /rk3
# /etc/mount /dev/rk2 /rk2
# /etc/mount /deev/rk3 /rk3


> File 11 - this is an older format tarball.
>

Nah, somebody else used the disk before for TAR, and then this was
overwritten with a unix filesystem.

What's weird is that this is a VENIX system, which should be V7 which
should have a different filesystem layout from V6. I'd think I wouldn't be
able to see some directories. I'll have to create a V7 system and mount it
there...

Warner