Imperative programming is a programming paradigm that uses a sequence of statements to reach a certain goal. It focuses on how to perform actions to achieve the expected result. Otherwise, functional programming paradigm concentrates on computing results rather than performing actions. In another wo
http://superuser.com/a/529844 (net-stat is deprecated)
http://www.cyberciti.biz/faq/how-do-i-find-out-what-ports-are-listeningopen-on-my-linuxfreebsd-server/
# nmap -sS -O 127.0.0.1
# lsof -i
# netstat -lptu
# netstat -tulpn