How do I grep for foo && !bar?

Question

I want to output all the lines in my source code which contain the string foo but don't contain the string bar. I tried this:

find . -name "*.[hc]pp" | xargs grep -n foo | grep -x bar 

However this doesn't work as I expected. How can I use grep in this way?

Answer 1

You want the -v flag, not the -x flag.

Mnemonic: negative.