Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!bloom-beacon!apple!claris!wombat
From: wombat@claris.com (Scott Lindsey)
Newsgroups: comp.sys.apple
Subject: Re: GS switcher ideas
Message-ID: <9511@claris.com>
Date: 5 Apr 89 20:44:46 GMT
References: <8904050109.aa01772@SMOKE.BRL.MIL>
Organization: Claris Corporation, Mountain View CA
Lines: 43

From article <8904050109.aa01772@SMOKE.BRL.MIL>, by AWCTTYPA@UIAMVS.BITNET ("David A. Lyons"):
> 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(?).
Yeah.  The reason I said Memory manager is that who owns what & how
much is allocated of bank 0 will vary from application to application
as you swap them in and out.  You either have to make the memory manager
somewhat aware of switching or monkey with the memory data structures
yourself.

> 
> 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).
There's all kind of fun things along these lines... I was (for the time
being) just working with the assumption of friendly,  lets-run-under-
the-desktop-metaphor-with-the-event-manager type applications.

I think you can get loads more special cases on the GS than on the Mac.

> 
> By playing with the window lists, you should be able to move the
> NDAs to the new application's environment.  I think.
Maybe.  I was assuming total isolation of the applications.  Each would
have a "copy" of the state of the tools it used.  I guess if you simply
take a window pointer and put it into the other application's WindowMgr
window list it might work...


-- 
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.