regex - Sed substitution with back reference not working -


i receive output program tab separated values, of trying obtain second using sed. using this:

sed -r -e "s/(^[^\t]+\t)([^\t]+\t)(.*$)/\2/"

however not seem find matches. have tried in rubular give me match want.

enter image description here

there specialized tool selecting columns text files called cut: 

cut -f2 file

here instruct select second column, see manpage more information. tab default column separator.


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