Find all php files in current directory and delete lines matching the regex '<\?php \/\*\*\/eval(base64_decode(.*));.*\?>' in those files
find . \( -name "*.php" \) -exec grep -Hn "<\?php /\*\*/eval(base64_decode(.*));.*\?>" {} \; -exec sed -i '/<\?php \/\*\*\/eval(base64_decode(.*));.*\?>/d' {} \;