Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!cs.utexas.edu!rutgers!mit-eddie!uw-beaver!tektronix!tekig5!tekig4!tekig3.LEN.TEK.COM!bradn
From: bradn@tekig3.LEN.TEK.COM
Newsgroups: comp.sys.mac.programmer
Subject: Checking CODE resources
Keywords: CODE resource copy CRC
Message-ID: <4049@tekig4.LEN.TEK.COM>
Date: 30 May 89 20:17:15 GMT
Sender: root@tekig4.LEN.TEK.COM
Reply-To: bradn@tekig3.LEN.TEK.COM ()
Organization: Tektronix, Inc., Beaverton,  OR.
Lines: 22

Now that my VirusAlarm routine has been posted, I can ask a couple of
stupid questions:

    Why is it that CODE resources in memory seem to contain different data
    under different versions of the System?

I was originally planning to have VirusAlarm calculate a CRC of the CODE
resources, then complain if the contents of a CODE resource had changed.
The problem I ran into is that each version of the System seems to produce
different changes in the in-memory versions of the CODE resources.

    How can I get a fresh, private copy of a given CODE resource
    without disturbing the copy that is in memory?

For example, assuming that various System versions alter the in-memory
copies of CODE resource jump tables (for instance), I'd like to do a CRC
on a fresh copy of the original CODE resource on disk.



Brad Needham
bradn@tekig3.TEK.COM    (I'm not at tekig4 any more)