>I seem to remember an article in macTech from way back
>dealing with 'unexpected' behavior occuring with
>YieldToAnyThread' and explaining the workaround.

Hello,

I searched the MacTech CD 13 and found the following:

===
Volume 10; issue  11; 'Thread Manager for Macintosh Applications'

Code sample #38:

Note: The SetThreadState, SetThreadStateEndCritical and YieldToThread
routines are usable during preemptive execution only when suggestedThread
parameter is either kNoThreadID or is another preemptive thread. Explicitly
requesting a cooperative thread to run from a preemptive thread is
dangerous and should be avoided.
===
Volume 12; issue 4; 'Threading Apple events'

'The fundamental problem is that AEProcessAppleEvent is non-reentrant. So
if you call it, you can't call it again until the event finishes
processing.'

This article then describes how to thread Apple events correctly using the
ThreadManager.
===
Volume 13; issue 1; 'How to use preemptive thread and how well'
===
Volume 13; issue 7; 'Mixed Up Threads'
===

Hope you find something useful there.

chris

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