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Date: Tue, 26 Aug 2008 20:23:17 -0700
From: Bill Campbell <freebsd@celestial.com>
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Subject: Re: Regular Expression Trouble
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On Tue, Aug 26, 2008, Martin McCormick wrote:
>I am trying to isolate only the MAC addresses that appear in
>dhcpd logs.
>For anyone who is interested, the sed construct that should do
>this looks like:
>
> sed 's/.*\([[ your regular expression ]]\).*/\1/' 
>
>The \1 tells sed to only print what matched and skip all the rest.
>

I just tried this, and it worked:

sed -n 's;.* to \([0-9:a-z]*\) via.*;\1;p' logfile

It would have been easier in perl or python where one could use
the pattern '.* to (\S+) via.*'.

Bill
-- 
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