Path: utzoo!yunexus!geac!syntron!jtsv16!uunet!mcvax!unido!ecrcvax!johng
From: johng@ecrcvax.UUCP (John Gregor)
Newsgroups: comp.unix.wizards
Subject: Re: Need memory at 0 on SUN
Message-ID: <647@ecrcvax.UUCP>
Date: 24 Oct 88 12:33:30 GMT
Article-I.D.: ecrcvax.647
References: <2768@fnatte.cs.chalmers.se>
Reply-To: johng@ecrcvax.UUCP (John Gregor)
Organization: ECRC, Munich 81, West Germany
Lines: 20

In article <2768@fnatte.cs.chalmers.se> augustss@cs.chalmers.se (Lennart Augustsson) writes:
>I need to run a program on a SUN3 (running SunOS 3.4) with virtual 
>read/write memory starting at virtual address 0.  Sun (in their infinite
>wisdom) has decided that memory starts at 0x2000.  Accessing 0-0x1fff causes
>a segmentation violation
>-- 
>	Lennart Augustsson
>Email:	augustss@cs.chalmers.se or augustss@chalmers.csnet

One possibility would be to keep a 'virtual' copy of page 0 somewhere else.
Then when your program references 0-0x1fff, you catch the fault, disassemble the
offending instruction, and emulate it using your virtual copy of page 0.

No, I don't have something that does this.  Yes, I know it is a horrible
kludge.  If someone has one of these already (or a better solution), I'd
like to know as well.

-- 

John Gregor                                       johng%ecrcvax.UUCP@pyramid.COM