Path: utzoo!attcan!uunet!cs.utexas.edu!sun-barr!apple!jkc
From: jkc@Apple.COM (John Kevin Calhoun)
Newsgroups: comp.sys.mac.hypercard
Subject: Re: XFCN/XCMD
Message-ID: <45905@apple.Apple.COM>
Date: 23 Oct 90 00:53:55 GMT
References: <90Oct22.134718*Arne.Venstad@elab-runit.sintef.no>
Distribution: comp.sys.mac.hypercard
Organization: Apple Computer Inc., Cupertino, CA
Lines: 12

In article <90Oct22.134718*Arne.Venstad@elab-runit.sintef.no>
Arne.Venstad@elab-runit.sintef.no (Arne Venstad) asks whether it's
safe to take a handle passed to an XCMD as one of its parameters,
munge it, and put it into the returnValue field of the XCMDBlock.

The answer is yes.  We made sure that this still works in 2.0.  We
check whether a handle used as one of the parameters is the same as
the handle in the returnValue field before disposing of it.

Kevin Calhoun
HyperCard Engineer
Apple Computer, Inc.