
Lines of code is typically indicative of effort that goes towards software development. So how do you count lines of code in your PHP application (or for that matter any specific types of files in any application). You can't manually open and count files, that would be a big waste of time. The *nix shell has a powerful set of tools that can help you count lines without having to do it manually.
find . -name "*.php" | xargs wc -l | awk '{print $1}' | awk '{total = total + $1}END{print total}'