From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <0a1d57f312ab3ed4c2b61d9bf021372b@vitanuova.com>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] rc question
Date: Thu, 23 Mar 2006 12:05:43 +0000
From: rog@vitanuova.com
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geoff:
> 	<>[4]/net/dns { echo google.com ip  >[1=4]; cat <[0=4] }

if you're expecting the cat to start at offset 0, you'd be mistaken
(the dup only ups the refcount on the underlying Chan,
so the seek offsets are shared).

cpu% echo one two three four five six > x
cpu%
cpu% <>[4] x {echo xxx >[1=4]; cat <[0=4]}
 two three four five six
cpu% cat x
xxx
 two three four five six
cpu%

you can probably do it with dd. the "read" command in inferno
is a more direct analog of the system call, and allows a "-o" flag
to set the offset. i found it quite often useful to know that one
is getting one and only one (p)read.