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Date: Fri, 21 Dec 2012 12:15:09 +0000
Message-ID: <CADSoG1tLsuMS8p-8z7z8PQBQQUtsHM20wD-KYZjnhgKj7JqOuA@mail.gmail.com>
Subject: Re: Intermittent failures retrieving process exit codes
From: Nick Lowe <nick DOT lowe AT gmail DOT com>
To: Andrey Repin <cygwin AT cygwin DOT com>
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Briefly casting my eye at the test case, as a general point, remember
that these termination APIs all complete asynchronously and I do not
believe it has ever been safe or correct to call another while one is
still pending - you are in undefined, edge case behaviour territory
here.

Win32's TerminateThread/ExitThread, that in turn calls the native
NtTerminateThread, only requests cancellation of a thread and returns
immediately.
One has to wait on a handle to the thread know that termination has
completed, for which the synchronise standard access right is
required.
The same is true of Win32's TerminateProcess/ExitProcess, in turn
NtTerminateProcess, where one waits instead on a handle to the
process.

Regards,

Nick

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