At Fri, 8 Dec 2006 10:06:46 -0500,
Michael Gorsuch wrote:
> 
> Hey all, I'm trying to find the right Unix tool to print out a matched
> regular expression, not just a line that matches.
> 
> For example,
> 
> echo [1234] | egrep \(1234\)
> 
> It matches the expression, but I only want to print the match, '1234'.
> 
> Any ideas?  I'm sure there's a unix tool I'm not using properly here...

There's always AWK for these things (my favourite in many cases):

	awk '{match($0, /1234/); print substr($0, RSTART, RLENGTH);}'

of course AWK can also do the sub() trick in the same way as with sed.

(any interpreted add-on language supporting REs will likely work too)

-- 
						Greg A. Woods

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