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Thread: Back Referencing in SED
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Old 01-02-2009
Christoph Spohr Christoph Spohr is offline
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Join Date: Sep 2008
Posts: 205
Hi,


Code:
sed 's/a\(..\)a/\1/' <<< "abba"

output:

Code:
bb

The backreference \1 saves the two characters betweens the as.
Everything between \(\) is saved and can be refereced with
\1 to \9 for each \(\).

HTH Chris