Path: utzoo!attcan!uunet!ns-mx!iowasp!deimos!ux1.cso.uiuc.edu!brutus.cs.uiuc.edu!samsung!emory!mephisto!ncar!ico!ism780c!randvax!ucla-an!stb!richard
From: richard@stb.uucp (Richard Conner)
Newsgroups: comp.sys.amiga.tech
Subject: Re: resource tracking
Message-ID: <1990Feb19.125050.9380@stb.uucp>
Date: 19 Feb 90 12:50:50 GMT
References: <355.25C92297@weyr.FIDONET.ORG> <131188@sun.Eng.Sun.COM> <9716@cbmvax.commodore.com>
Reply-To: richard@stb.uucp (Richard Conner)
Organization: The Serial Tree BBS, +1 213 397 3137
Lines: 42

In article <9716@cbmvax.commodore.com> valentin@cbmvax.cbm.commodore.com (Valentin Pepelea) writes:
>In article <131188@sun.Eng.Sun.COM> cmcmanis@sun.UUCP (Chuck McManis) writes:
>> 
>>Something I personally would like to see would be a "runprotected" command
>>that would start a program and setfunction the appropriate vectors so that
>>the program would run with the MMU protecting all addresses outside of it's 
>>range.
>
>Not that I did not think about it. The problem is that I can not achieve full
>recoverability if a task goes astray. The problem lies with the definition
>and useage of MEMF_PUBLIC. Memory defined as such is free to be written to
>by any task or interrupt in the system. That's where all the system structures
>are.
>	[...]
>Full recoverability in a memory protected system can therefore be achieved only
>by changing the definition of the MEMF_PUBLIC flag, and by adding parameter
>checking to all system functions that cause another task or interrupt to
>execute some code. For example the DoIO() function causes a device to process
>a request. If the request provided is scrambled, a crash will occur under the
>device's context.

I can live with that...  I don't think you really mean you need to change the
definition of MEMF_PUBLIC -- just the current (ahem) "usage" by perhaps
less-than-competents who can't read?
 
>Both these changes would cause some programs to fail, if implemented. So for
>backwards compatibility reasons, it is unlikely that memory protection will
>ever be implemented on AmigaDOS. I for one would gladely implement them as they
>require no great engineering effort, but the god in the corner office is 
>unlikely to approve, for backward compatibility reasons.

Plleeeeeeez?  How about this... you PROVIDE software selectable memory
protection - such that perhaps holding down a mouse button/key combination
or something - invokes AmigaDOS 1.n with the memory protection, otherwise
it runs rampant for "bass-ackwards" compatibility?

...by the way, who do we address the rotten tomatoes -- oops -- I mean
the bribes to in the corner office? he he he. ;-)

-Richard
-- 
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