Re: Re: Run CMS non-virtualiized?

On Sunday, August 29, 2010 Dave Wade wrote:
> They are just the normal DIAGs so I don't believe there isn't a list
> any where. I think the main one is for disk i/o but you could do a
> PER TRACE of the IPL to see what actually happens. I guess CMS will
> IPL without some DIAGs but then other commands would fail.
 
Which version of CMS are we talking about? The VM/370 version?

Almost from the very start Hercules had support for some of the CP
DIAG codes, because one of the scenarios envisaged for Hercules in the
1999 timeframe was that CMS would run directly in a Hercules machine
without CP. The idea was to offer some kind of mainframe-like personal
computing environment (what I considered the PC "ought" to have been!)
Being very light on resource consumption, CMS was ideally suited to
the somewhat limited PC computing power of the time.

At the time the idea did not gain much traction, as people seemed more
interested in running MVS, so the project was never completed, but the
DIAG support is still there (in vm.c).

It would be relatively straightforward to add the missing DIAG codes.
AFAICR they are well-documented in the VM manuals.

To find out which DIAG codes are missing, you just have to IPL CMS,
see where it fails, add the missing DIAG, and repeat until it no
longer fails :-)

--
Regards,
Roger Bowler
http://perso.wanadoo.fr/rbowler
Hercules "I can't believe it's not a mainframe!"