Best way to learn how to port other OSes?

[Robert Myers]

What's the best way to learn how to do this?  Is it by examining one of the demo scripts and creating a variant?  I would like to try bringing v6 and v7 Unix to my Qbone.

[Jay Jaeger]

I set up a little convention where I have my own directory for scrips and images.  I then copy the demo scripts and images (or use my own images)  and make the necessary file path changes.  That way a software update or an simulated image update doesn't affect my stuff.  

6th edition Unix should not be difficult - I seem to recall doing it, and maybe there were already demo scripts?  If I were doing it, I'd just use Simh to prepare RK05 images from the 6th edition distro.  But I have a PDP-11/34 (among other things) which can run 6th edition off of a *real* RK05 too.   Not sure what issues might be out there for a more modern processor on a QBus that might make 6th edition unhappy.

7th edition would need some work because it doesn't support RK05 - nor does it support RL's or MSCP, though I recall someone having adapted it for an RL02.

JRJ

[Robert Myers]

Thanks for the suggestions!  I'll go and create the directories and copy one of the sample scripts over to see what I have to do.

Bob

[Michael Robinson]

I concur.  I usually either copy over a similar demo script and disk images into a fresh directory and then modify with abandon.  I often build fresh disk images with simh since that's a lot faster than the hardware CPUs!  Sometimes you need to work with install media (like tapes) that the Q/Unibones don't (yet?) support; again, simh makes that easy.  

All told, I've gotten quite a collection of OSes running, all using the Unibone for mass storage: 

https://www.youtube.com/watch?v=TP7Na3caNn0

...and there are yet more to try!

If you run into problems, just ask.  Sometimes the original maintainers/authors/etc. are reading the various lists :)

Final caveat: make sure to keep good notes about what is where.  My collection of directories has begun to get a bit sprawling, and I forget what's where.  (Like, on which RT-11 disk image did I stash that FORTRAN program I was hacking last month???)

Regards,
Michael