Simple Internet Chat Service

Create a server which opens a port and accepts connections
from clients. It should be able to accept and service up
to eight clients at once.

Also create the client that will make it easy for people
to use this service.

When a client first connects, the server must send to the
new client the initials of everybody who is already connected.
The client should display this list to the user. The user
then types in their own initials which are sent to the server.
The server must not allow a client to continue until the
identifying initials are received.

From then on, users may type at any time they wish. The client
sends their lines of text to the server.

When the server receives a line of text from a client, it must
send that line, with the senders initials prefixed, to all other
clients.

When a client receives a line of text from the server, it displays
it for the user to see.

When a client disconnects or logs off, the server must inform
all remaining clients of the event.



So to summarise, everyone sees what everyone types as soon as
they type it, and they also see who typed it.


**** Use TCP and poll()
**** The notes for class 18 remind you how to do all of this
**** Make it tidy and comprehensible
**** Explain things.