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From: cwinemil@digi.lonestar.org (Chris Winemiller)
Newsgroups: comp.windows.ms
Subject: How are multiple Windows applications scheduled?
Message-ID: <920@digi.lonestar.org>
Date: 29 Aug 90 19:04:31 GMT
Sender: cwinemil@digi.lonestar.org
Organization: DSC Communications, Plano Tx.
Lines: 16

How does Windows 3.0 achieve the "simultaneous" execution of multiple
Windows applications? (Note: I am excluding "simultaneous" execution of
multiple DOS sessions in the 386 enhanced mode.) Must the Windows
applications be written in such a way as to voluntarily "relinquish"
control of the CPU occasionally? Or are the Windows applications
written as if each is the only one running on the CPU? In other words,
does Windows do non-preemptive "scheduling" or preemptive "scheduling"?
Or is it some other scheme? I'd be particularly interested in comments
from those who have actually developed Windows applications.  I don't
have the SDK and have not written any Windows applications (obviously),
otherwise I wouldn't need to ask! :-)
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