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RE: [MiNT] DATE/TIME cookies



> From: owner-mint@fishpool.com [mailto:owner-mint@fishpool.com]On Behalf
> Of Petr Stehlik
> Sent: Friday, February 26, 1999 1:49 PM
> To: Konrad Kokoszkiewicz
> Cc: mint
> Subject: RE: [MiNT] DATE/TIME cookies
>
>
> > No, I am asking why you resist to do the corner clock as ACC
> (or process)
> > instead of using stuff that breaks the memory protection concepts.
>
> Please tell me how DATE/TIME breaks the memory protection and why
> _CPU, _FPU  and other cookies do not break it.

Either the DATE/TIME cookie contains the date and time values themselves. In
this case they need to be updated regularly by somebody -- either the kernel
or a background process. This does not break memory protection, but is a
waste of time, especially if the internal time format is not DOS based
anymore.

In the other case the cookie values point to kernel internal variables,
which is a big NO.

I still don't understand why you need to do all of this in the interrupt.
There are myriads of corner clocks that do not need that type of hack.
Besides, I ask again: how do you access the screen from within the
interrupt?

Regards, Julian