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Cc:	mjd@central.cis.upenn.edu
Subject: Y-shaped pipeline
In-Reply-To: Your message of "Thu, 09 Jul 92 18:08:57 EDT."
             <199207092208.AA00518@betty.cs.widener.edu> 
Date:	Fri, 10 Jul 1992 11:29:48 -0400
From:	Mark-Jason Dominus <mjd@saul.cis.upenn.edu>


I have a program, `why', which expects to write output
to file descriptors 4 and 5.  

	why >[4] descriptor-four-log >[5] descriptor-five-log

works fine; the data that `why' writes to desriptor 4 winds up in
`descriptor-four-log', and the data that `why' writes to descriptor 5
goes to the file `descriptor-five-log'.

Now I want the descriptor 4 data to be piped into the stdin of some
command, say `rev', and I want the descriptor 5 data to be piped into
another command, say `cat -n'.  This doesn't work:

	why |[4] rev |[5] cat -n

because that means to connect descriptor 4 of `why' to descriptor 0 of
rev, and then to connect descriptor 5 of rev to descriptor 0 of cat -n.

How can I connect a command to two pipes at once?