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Date:	Thu, 16 Jul 1992 06:13:37 -0400
From:	malte@techfak.uni-bielefeld.de
Message-Id: <9207161013.AA00612@dahlie.techfak.uni-bielefeld.de>
To:	rc@hawkwind.utcs.toronto.edu
Subject: Re: Question about redirection
In-Reply-To: Mail from 'jutta@cs.tu-berlin.de'
      dated: Thu, 16 Jul 92 2:02:48 MET DST

I'm sorry for not being precise with my question. What I want to know
is why
	{ echo stderr >[1=2]; echo stdout } >[2=1] > /dev/null
and
	{ echo stderr >[1=2]; echo stdout } |[2=1] cat > /dev/null

although lexically similar, differ in their semantics, while

	{ echo stderr >[1=2]; echo stdout } |[2=1] cat > /dev/null
and
	{ echo stderr >[1=2]; echo stdout } >[2] /dev/null

look quite different, but are semantically equal. I became aware of this when
I was asked about something similar by a beginner. I feel it is hard to
explain why >[n=m] differs from |[n=m].

Malte.