Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!cs.utexas.edu!inebriae!al
From: al@inebriae.UUCP (Al Evans)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Purge or Revert Resource?
Message-ID: <376@inebriae.UUCP>
Date: 26 Jun 89 19:09:05 GMT
References: <82203@ti-csl.csc.ti.com> <689@biar.UUCP>
Reply-To: al@inebriae.UUCP (Al Evans)
Organization: PowerTools
Lines: 31


In (some lost attribution line), Robert writes....

>Check out DetachResource.  Assuming H is a handle to a resource such as
>returned by GetResource, DetachResource(H) ``unlinks'' the handle so
>the resource manager no longer recognises it as a handle to a resource.
>
>So you can do something like this:
>
>	DetachResource(H);
>	DisposHandle(H);
>	H:=GetResource('DERF',0);
>
>to do your reversion.  I'm pretty sure that H will point to the same master
>pointer after the GetResource call.  IM-I has some diagrams in the Resource
>Manager chapter that explain DetachResource quite well.

I could be wrong, but I see nothing in IM which would imply this is true.
Seems to me it would be equivalent to saying:

	DisposHandle(H);
	H:= NewHandle(someSize);

and expecting H to be the same before and after. Though this may effectively
be the case, I don't think anything in IM *guarantees* it.

                                              --Al Evans--

-- 
Al Evans    {tndev,texbell,ssbn}!inebriae!al
            al@inebriae.WLK.COM