Non greedy (reluctant) regex matching in sed?

Question

I'm trying to use sed to clean up lines of URLs to extract just the domain..

So from:

http://www.suepearson.co.uk/product/174/71/3816/

I want:

http://www.suepearson.co.uk/

(either with or without the trainling slash, it doesn't matter)

I have tried:

 sed 's|\(http:\/\/.*?\/\).*|\1|'

and (escaping the non greedy quantifier)

sed 's|\(http:\/\/.*\?\/\).*|\1|'

but I can not seem to get the non greedy quantifier to work, so it always ends up matching the whole string.

Answer 1

This can be done using cut:

echo "http://www.suepearson.co.uk/product/174/71/3816/" | cut -d'/' -f1-3

Answer 2

sed -E interprets regular expressions as extended (modern) regular expressions

Update: -E on MacOS X, -r in GNU sed.