Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!bloom-beacon!apple!apple.com!cep
From: cep@apple.com (Christopher Pettus)
Newsgroups: comp.sys.mac.programmer
Subject: ApplicationTrap? (was Re: Need some MF help)
Message-ID: <1294@internal.Apple.COM>
Date: 11 Apr 89 18:19:42 GMT
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References:<1562@neoucom.UUCP> <28399@apple.Apple.COM> <43464@XAIT.Xerox.COM> <1227@internal.Apple.COM> <6849@saturn.ucsc.edu>
Organization: Apple Computer, Inc.

In article <6849@saturn.ucsc.edu> alibaba@ucscb.UCSC.EDU (Alexander M. 
Rosenberg) writes:
> >>         ApplicationTrap ( ... ); this trap would be guaranteed to 
never
> >> be used by Apple but the application would have license to patch it. 

> >What would you do with this?  

> What if one wanted an app to talk to code preloaded by an INIT, hmm?

How would this work?  If the INIT patched the (theoretical) 
ApplicationTrap when it was first loaded, that trap would be patched for 
all applications in the system, for good (unless the INIT unpatched it, of 
course).  If the application patched the trap, it would need to know the 
address of the code the INIT loaded, in which case it could just JSR to it.

-- Christopher Pettus                     |
   Network Systems Development            |
   Apple Computer, Inc.                   |
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   AppleLink: PETTUS.C                    |