Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!cs.utexas.edu!usc!apple!keith
From: keith@Apple.COM (Keith Rollin)
Newsgroups: comp.sys.mac.programmer
Subject: Re: System 7 and cache
Message-ID: <48782@apple.Apple.COM>
Date: 2 Feb 91 22:17:16 GMT
References: <1075.27AA0D8A@stjhmc.fidonet.org> <11958@goofy.Apple.COM>
Organization: Apple Computer Inc., Cupertino, CA
Lines: 39

In article <11958@goofy.Apple.COM> Greg@AppleLink.Apple.Com (Greg Marriott) writes:
>In article <1075.27AA0D8A@stjhmc.fidonet.org>, Lawson.English@p88.f15.n300.z1.fidonet.org (Lawson English) writes:
>> 
>> Keith Rollin writes in a message to All
>> 
>> KR> You know, I'd also heard that FlushVolling didn't flush everything. 
>> KR> However, I traced through the code once, and it looks like it 
>> KR> flushes everything to me. At least, everything important. And 
>> KR> certainly everything pertaining to files
>> 
>> It may not flush everything pertaining to FinderInfo...
>
>It does.

Thanks for clearing that up, Greg. It looks like Lawson is referring
to the times when one crashes, and things like Finder windows open up
in an old formation.

Trying to analyze why that's so from the outside, you can come up with
two possible reasons for this:

1) That the new information is not flushed to disk, or 
2) That the new information is not in the right place to be flushed
   to disk.

Given confirmation that the former is not true, I guess that the
problem lies in the caching that the Finder itself does. The Finder
normally caches all the information known as Finder Info in its own
data structures, and doesn't transfer them back into the appropriate
FCB's and VCB's until it absolutely had to. If it did this, then a
FlushVol would keep that information up-do-date. But it doesn't, so the
Finder has the habit of opening up windows in their old states.

-- 
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"Argue for your Apple, and sure enough, it's yours" - Keith Rollin, Contusions