Question

I have a list that looks like this:

server
server.apple.com
server.apple.com
server
server.apple.com

Now, I would like to add “.apple.com” to the lines that says just “server”. I’ve tried sed with:

sed -e 's/\bserver\b/server.apple.com/g'

Answer 1

You could use:

sed 's/^server$/server.apple.com/g'

^ means start of line and $ means end of the line.

You also don’t need the -e argument, as this is just basic regex.

If you want case insensitive search for server (also match SERVER and SErvEr) you can use the I function, however it is not supported by various versions of sed:

sed 's/^server$/server.apple.com/Ig'

If you don’t have a sed version that supports I you can use:

sed 's/^[Ss][Ee][Rr][Vv][Ee][Rr]$/server.apple.com/g'