[Info-vax] Volatile, was: Re: yet another sys$qiow question

[JF Mezei]

On 15-08-21 09:36, "VAXman- "@SendSpamHere.ORG wrote:

> may need to wait in which case, the driver "forks".  Once that thing that
> the driver has been waiting for has occurred, the driver code is revisited
> by the OS dispatching to where the driver forked.  Context is saved in the
> fork block to allow the driver to pick up where it left off.  

Thanks. So when an IO (device level) completes, the driver continues
where it left off.  Does it have to explicitely re-establish context by
reloading the informtion that was saved at fork time, or is that all
done automatically ?

In other words, does the driver continue as if nothing had happened
between the fork and the next instruction ? Or upon completion of the
fork, does it do work to restore context for that particular IO ?

Is it fair to state that the context that is saved when doing the fork
is not volatile ? (aka: a blob of data that won't change during the time
of the fork ?)