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Message-ID:	<001f01c0b690$d8555230$0200a8c0@lifelesswks>
From:	"Robert Collins" <robert DOT collins AT itdomain DOT com DOT au>
To:	<cygwin-developers AT cygwin DOT com>
Subject:	fifo's
Date:	Tue, 27 Mar 2001 17:37:56 +1000
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X-OriginalArrivalTime:	27 Mar 2001 07:32:43.0794 (UTC) FILETIME=[1C9C8720:01C0B690]

well my test cases show some interesting behaviour...

1 writer, 2 readers - the readers get the written blocks in a round
robin style. (ie if the writer writes
"1\n"
"2\n"
"3\n"
the 1st reader will get
"1\n"
"3\n"
and the 2nd reader
"2\n"

2 writers, 1 reader - seems to be atomic writes (no mixed data), but if
the writes are interleaved, the reads get the interleaved data. So
writers have to buffer their output to atomic chunks.

2 writers, 2 readers - seems to be the round robin outputs, atomic
writes, interleaved data as appropriate (union of the first two tests).

As far as interoperability with non-cygwin apps goes... my comment is
"If they wouldn't understand native Named Pipes for redirecting stdout,
then this is no different." I will attempt structure this code so it can
be pulled out to a separate dll for linking with mingw applications, or
to be built into an IFS driver down the track. (So the native apps could
be redirected to //./...../namedpathalias/ when called from a cygwin
app.)

Rob

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