[SOLVED] A problem about GREP

Young_zhang · 11-30-2011, 02:11 AM

hi everyone.
I want to find all the lines which matches "aa" or "bb" in a certain file.
how could i write the grep clause?
for example:
cat filename|grep aa
can list lines contain aa.
but now I want to list lines contain "aa" or "bb" using a single clause.
thanks a lot.

evo2 · 11-30-2011, 02:13 AM

Hi,

sounds like you want the -E (--exteneded-regexp) flag.

Code:

grep -E 'aa|bb' filename

Evo2.

PS. Also avoids the useless use of cat :-)

Young_zhang · 11-30-2011, 02:18 AM

I got it,thanks a lot.