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From: Achim Gratz <Stromeko AT nexgo DOT de>
Subject: Re: [Bug] Named Pipes (FIFO) / Bash
Date: Wed, 10 Aug 2011 17:05:47 +0200
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Achim Gratz <Stromeko AT nexgo DOT de> writes:
> In other words, opening the pipe is non-blocking, even though no
> listener is present.  Listing /proc/self/fd lists fd 6 as opened to FIFO
> /tmp/pipe, but any output to it blocks indefinitely.  I believe that the
> FIFO has in fact never been opened as far as the system is concerned.
> The output then blocks on the apparently not-open FIFO (I should be
> getting a SIGPIPE instead when trying to write into a pipe that has no
> listener).

I've checked again with the latest snapshot (2011-08-03), after doing a
full update and rebaseall.  While the FIFO implementation still does not
conform to POSIX w.r.t. blocking, it now gives consistent results again
(as it was in Cygwin 1.5), does not block listeners indefinitely anymore
and kills a listener with SIGPIPE when the producer goes away.  So if
the scripts are written to assume that behaviour, you can again use FIFO
to synchronize processes.


Regards,
Achim.
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