mardi 5 mai 2015

How to avoid perl -pe from printing unmatched lines

The following will print out "chicken", which is expected:

echo "I like chicken" | perl -pe 's|.*(chicken).*|\1|'

Output: chicken

However, the following will print out "I like bacon" even if "chicken" was not matched:

echo "I like bacon" | perl -pe 's|.*(chicken).*|\1|'

Output: I like bacon

How can I avoid the unmatched string from being printed out?

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