Path: utzoo!attcan!uunet!lll-winken!csd4.milw.wisc.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!UIAMVS.BITNET!AWCTTYPA
From: AWCTTYPA@UIAMVS.BITNET ("David A. Lyons")
Newsgroups: comp.sys.apple
Subject: GS switcher ideas
Message-ID: <8904050109.aa01772@SMOKE.BRL.MIL>
Date: 5 Apr 89 06:03:00 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 47

>Date:     Tue, 4 Apr 89 19:34:25 GMT
>From:     Scott Lindsey <claris!wombat@APPLE.COM>
>Subject:  Multitasking, IIgs etc
>
>[...] All switching would go through GetNextEvent (since the GS
>doesn't have WaitNextEvent, it's not quite possible to do Multifinder
>the way the Mac does).

Hey, the Mac didn't used to have a WaitNextEvent, either. MultiFinder
works okay (less efficiently) with applications that don't know about
WaitNextEvent.

>The only things that would have to be switcher aware (read: patched
>by the switcher) are the Event Manager, the tool Locator, any
>FooStartup, FooShutdown where Foo is a tool used by one of the
>applications and the memory manager.  Finally, NDA's would have to be
>treated specially.

Hmmm...I don't agree with your list of things that a Switcher would
need to patch.  The memory manager shouldn't need any special
handling.  Sound tools status would have to be preserved, including
the contents and status of the DOC RAM.  Status of toolsets with no
direct pages needs special handling:  text tools comes to mind.
Ditto for serial port firmware(?).

Clipboard (scrap manager) contents would need to be transferred from
application to application, including for applications that don't
normally keep their clipboard contents in the scrap manager (ya gotta
trick 'em into thinking an NDA has been opened so they'll put it on
the system scrap for you).

Then there are fun tricks to play with $E0 and $E1 vectors that are
affected by QD, QD Aux, Event Manager (some of which may not be
started in some of the switched applications).

By playing with the window lists, you should be able to move the
NDAs to the new application's environment.  I think.

>Scott Lindsey     |"Cold and misty morning. I heard a warning borne in the air
>Claris Corp.      |    About an age of power when no one had an hour to spare"
>ames!claris!wombat| DISCLAIMER: These are not the opinions of Claris, Apple,
>wombat@claris.com |    StyleWare, the author, or anyone else living or dead.

 --David A. Lyons              bitnet: awcttypa@uiamvs
   DAL Systems                 CompuServe:  72177,3233
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