[softwarelist] Re: A file that makes OvPro type=5 then 'filecore in use'

In message <P3dJ0BBWln1JFwkd@xxxxxxxxxxxxxxxxxxx> you wrote:

> In message <e8815d4650.Jo@xxxxxxxxxxxxxxxxxxxxxxxx>, John Tytgat 
> <John.Tytgat@xxxxxxxx> writes
> >> isn't protected (and impossible to unprotect). I've said before how many
> >It is indeed far from ideal but note that the zero page is protected in
> >RISC OS 4 (or in Select ? Certainly in RISC OS 6) for User Mode programs.

To follow up on this, it is not only the zero page but several other,
for RISC OS kernel sensitive, memory areas, see
<URL:http://select.riscos.com/prm/memory/misc.html>.

> But don't most people turn off that protection (ISTR)?

I would be surprised if that's the case as I'm not aware this can be
easily switched off.  And even it would be easy to do, it is kinda
foolish and pointless to do.

> I think the worst thing, and I'm guilty of doing it, is using direct 
> write to memory to communicate with modules - since that is legal, it 
> allows any program to accidentally corrupt the insides of RISC OS.

It all depends which memory area you're talking about.  I was talking
about zero page currently being protected for some versions of RISC OS
as far as I'm aware.  E.g. writing to RMA memory is something different,
and yes if you poke outside the block you're supposed to write, things
go painfully wrong.  Lukely rogue C/C++ based programs more ofter write
to zero page than to RMA.

John.
-- 
John Tytgat, in his comfy chair at home                                 BASS
John.Tytgat@xxxxxxxx                             ARM powered, RISC OS driven
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