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From: time@tbomb.ice.com (Tim Endres)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Shared memory
Message-ID: <1CE00001.6q9i4t@tbomb.ice.com>
Date: 25 Nov 90 15:32:33 GMT
Reply-To: time@tbomb.ice.com
Organization: ICE Engineering, Inc.
Lines: 28
X-Mailer: uAccess - Mac Release: 1.0.2


In article <3171@cernvax.cern.ch>, marty@cernvax.cern.ch (hugues marty) writes:
> Is there a way of having shared memory? I don't want to use a driver.
> I thought of allocating a non-relocatable block in the system heap
> (yes, the system heap) and pass the address via a file. Is it a good
> way?
> 

This is perfectly valid depending on your case.

First, the file mechanism leaves a lot to be desired in terms of checking
for validity etc, but will work.

Second, you need to determine your memory requirements. If they are
very small ( < 2048 ) then you can usually the system heap space from
within an application, but if the requirements are large (> 4K), then
you will need some type of INIT to get the space at boot time.

Third, if you wind up needing an INIT, you may as well write a driver!

Finally, sample driver code to do all of this is available.

tim.

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