Having fun with netcat.
Netcat or nc in short can be aptly described as one of those two letter command-line tools that have all of legendary UNIX magic and power.
nc however is a new program and does not share the age of well known programs like cat or dd. However its power and versatility make one think why no one came up with this before.
Past is past. Let us worry about the future now. The future is VoIP, multimedia streaming, video on demand...but we are digressing. We are discussing netcat here.
Interestingly netcat is going to help us in future as the best way to debug future network protocols. Peer to peer networking is often touted as the wave of the future Internet and I shall talk about an interesting anecdote of how invaluable netcat proved to me whilst testing my peer topeer NAT traversal library.
It is not very likely you have used it. So let us start with few simple exams before we get on to nontrivial ones.
$nc -l -p 1234