Task: Counts total lines in PHP and JS files in /testbed.
Command: find /testbed -name '*.js' -or -name '*.php' | xargs wc -l | grep 'total'  | awk '{print $1}'
Equivalent command: find /testbed -type f \( -name '*.php' -o -name '*.js' \) -exec wc -l {} + | awk '{s=$1} END {print s}'