To send data over a network, the data has to conform to a certain format or protocol. The Transmission Control Protocol / Internet Protocol (TCP/IP) is one of the core protocols to be used on the internet.
The following screenshot shows how to communicate over TCP/IP between a Julia TCP server and a client (see the code in Chapter 8\tcpserver.jl):
The server (in the upper-left corner) is started in a Julia session with server = Sockets.listen(8080), which returns a TcpServer object listening on port 8080. The conn = accept(server) line waits for an incoming client to make a connection. In a second terminal (in the lower-right corner), we start the netcat (nc) tool at the prompt to make a connection with the Julia server on port 8080, for example, nc localhost 8080. Then, the accept function creates a TcpSocket object on which...