On 2015-03-19 23:57, Timothe Litt wrote:
On 19-Mar-15 18:43, Johnny Billquist wrote:
All true. Except I don't think VMS actually do relocation at load
time. The VAX instruction set was capable enough that pretty much all
code you ever wrote was already PIC. The only things to resolve were
external symbols, but I don't think VMS allowed shareable images to
refer to external, unresolved symbols to start with. But I might be
wrong on that.
You are. The image activator dealt with G^ symbol fixups. One tried to
avoid them, as they caused imgact to do extra work, and the instructions
that needed to be fixed-up made their pages non-sharable. You can write
PIC code, on VAX, but don't have to. But that's another diversion, and
I have other things to do.
So do I. Bringing in VMS was in itself very tangential to the thread,
which was already very tangential.
And yes, -20F looks truly like a weird hybrid, with even the
documentation not correct.
The documentation is correct, as far as it goes. It's just not
complete. Any doc has some errors. And this was reverse-engineered.
Be grateful that some of us fought for funding to get the internal notes
and training materials published.
Well, I still consider that more wrong than incorrect.
Probably. But unless you also have 11D code, don't be too sure. 11M
practiced code reuse before it was popular. M may have started with D's
BOOT.
Nope. The comments in the BOOT sources even says it is 11M.
That doesn't contradict my point. Its origin may well have been 11D,
before 11M adopted it.
You can continue to argue that. That don't make it correct. And then we
could go on arguing that it all comes from RSX-11C one way or another.
It is clear that the code in the listing of BOOT.MAC included in the
Tops-20 files are directly imported from RSX-11M either way.
his was the basis of the 20F drivers.
Loadable device drivers have been around for a long, long time in 11M.
But, unlike 11D, device drivers in 11M were never tasks.
I've been around longer. When I first used 11M, they had to be sysgened
into the exec. It was big news when they became (optionally) loadable.
And somewhat of a pain to upgrade, though avoiding the full exec TKB was
helpful when developing.
Yes. And now we're talking about RSX-11M V2 or earlier. Which place us
at or before the KL was released.
And the drivers in -20F do appear to be like tasks, and they even
define the RSX11D symbol, so they definitely are in the 11D vein.
As I said, keep looking and you'll keep validating what I wrote. This
started when I said the drivers came from 11D, and you disbelieved me...
Yes, because that was not what was suggested by the RSX-20F manual...
As far as I'm concerned, this conversation is over.
I don't know where this hostility comes from. Noone demanded that you
reply. I'm trying to figure some things out, as it turned out some
things I believed was proven wrong.
Johnny
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