sed command help
 

Hai.

My file has
proxy-connection
connection
server-connection

i try to print only the 2 line
connection

sed -n "connection" filename
but print all the lines

grep '^connection$' FILE

but, with sed:

sed -n '/^connection$/p' FILE

-- The slashes tell sed it's a regex. ^ and $ anchor the expression at the beginning and end of the line. The 'p' flag prints. The regex is the same in grep but it knows it's a regex and always prints only matching lines by default.

Presuming no whitespace interference ...

Really good SED tutorial here:
http://www.grymoire.com/Unix/Sed.html

Look at the part about addresses