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From: "John Emmas" <johne53 AT tiscali DOT co DOT uk>
To: <cygwin AT cygwin DOT com>
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Subject: Re: Named pipes (blocking problem)
Date: Mon, 22 Dec 2008 18:23:40 -0000
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Many thanks guys - the blocking pipes are being created with PIPE_WAIT and
without FILE_FLAG_OVERLAPPED and they successfully block if I build under
VC++ but not when I build under Cygwin.  I must confess, I don't understand
the subtle difference between asynchronous operation and nonblocking
operation but I'll see what I can find out from Google.


----- Original Message ----- 
From: "Christopher Faylor"
Sent: 22 December 2008 17:28
Subject: Re: Named pipes (blocking problem)
>
> If the OP is creating a pipe using CreateNamedPipe and then trying to
> somehow read it using Cygwin's I/O library then I wouldn't be surprised
> to see strange behavior.  Otherwise, Cygwin does not impose any strange
> limitations on CreateNamedPipe.
>
Thanks Christopher.  This is really at the heart of what I'm trying to find
out.  Does Cygwin implement its own versions of CreateNamedPipe() and
ReadFile() or does it simply link to the standard Windows versions?  If it
passes the calls over to Windows then I'm baffled about why I'm observing
different behaviour.

John

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