Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!rochester!cornell!biar!trebor
From: trebor@biar.UUCP (Robert J Woodhead)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Purge or Revert Resource?
Message-ID: <689@biar.UUCP>
Date: 26 Jun 89 03:04:48 GMT
References: <82203@ti-csl.csc.ti.com>
Reply-To: trebor@biar.UUCP (Robert J Woodhead)
Organization: Biar Games, Inc.
Lines: 26

In article <82203@ti-csl.csc.ti.com> holland@m2.csc.ti.com (Fred Hollander) writes:
>I want to revert a resource that is already loaded into memory by
>reading the resource from the resource file and discarding any
>changes.  I also want to keep the same handle to the resource.  Can
>this be done?  LoadResource won't do anything if it's already loaded.
>I can't find a PurgeResource procedure.  Is there any way to force a
>resource to be purged or to force a resource to be reloaded?

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.

-- 
(^;-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-;^)
Robert J Woodhead, Biar Games, Inc.   !uunet!biar!trebor | trebor@biar.UUCP
  ``I can read your mind - right now, you're thinking I'm full of it...''