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Date:	Thu, 23 Feb 2006 16:59:35 -0500
From:	Christopher Faylor <cgf-no-personal-reply-please AT cygwin DOT com>
To:	cygwin AT cygwin DOT com
Subject:	Re: Shells hang during script execution
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On Thu, Feb 23, 2006 at 04:35:12PM -0500, Ernie Coskrey wrote:
>Here's a description of a second hang condition we were encountering, along with a patch for it.
>
>
>The application (pdksh in this case) does a read on a pipe, which eventually calls pipe.cc fhandler_pipe::read in Thread 1.  This creates a new cygthread with "read_pipe()" as the function.  Then it calls th->detach(read_state).
>
>When the hang occurs, the new thread gets terminated early, before
>cygthread::stub() can call "callfunc()".  You see the error message
>"erroneous thread activation".  I'm not sure what's causing the thread
>to fail activation, but the result is, the read_state semaphore never
>gets signalled.

Sorry but this is another band-aid around a problem.  The real problem
is that the code shouldn't get into the state that you are describing.
That's why cygwin prints an error message - it is a serious problem.
Making the code deal gracefully with a problem like this isn't going
to solve the underlying issue.

If you can figure out what's causing the erroneous thread activation
then that will be the real culprit.

cgf

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