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Date: Mon, 12 Mar 2012 18:02:04 -0400
From: Christopher Faylor <cgf-use-the-mailinglist-please AT cygwin DOT com>
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Subject: Re: Can't reliably redirect standard output from C# program in recent Cygwin
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On Mon, Mar 12, 2012 at 05:28:17PM -0000, James Johnston wrote:
>Well, good call.  I shouldn't have jumped to conclusions.  Both my C++
>and C# examples still fail:

Not really a call.  It was obviously different failure.  The previous
fix wasn't even pipe related.

But, regardless, Corinna (who has more time these days to look into
this type of thing) found a damning piece of MSDN documentation which
indicates that a write of zero bytes to a pipe will cause a read of
zero bytes on the other end of the pipe.  So, a program which assumes
that a zero byte read means EOF, like most Linux programs, will stop
processing when it sees the zero bytes from ReadFile.

Corinna sent me a patch to fix the problem which I've mildly tweaked and
installed.  It's in the latest snapshot.

cgf

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