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From: dave@labtam.oz.au (David Taylor)
Newsgroups: comp.unix
Subject: Re: UNIX pipe bug
Keywords: pipe,UNIX
Message-ID: <3690@zorba.Tynan.COM>
Date: 13 Jul 90 21:06:33 GMT
References: <3589@zorba.Tynan.COM> <3640@zorba.Tynan.COM>
Sender: dtynan@zorba.Tynan.COM
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Approved: dtynan@zorba.Tynan.COM

idall@augean.ua.OZ.AU (Ian Dall) writes:

>mknod PIPE1 p
>cat ~/.login | tee PIPE1 | wc | cat - PIPE1

>Should work. My .login is around 600 bytes. It does work on a vanilla
>system V.2.2 box I have, but it doesn't work on a Sun4 running SunOs 4.

Shouldn't work ... classic deadlock situation.

cat can't start reading PIPE1 until it has finished reading standard
input which cn't occur until wc finishes, which can't occur until tee
finished, which can't occur until someone (cat) is willing to read PIPE1.
--

.. Dave T.