What does “program &” mean on the command line?

Question

I need to develop a client and server program with using sockets. My program should get port number from the command line. I saw an example which says \"myprogram 2454 &\".<

Answer 1

It means to start the process in the background. http://tldp.org/LDP/abs/html/x9644.html so that you may continue to use your shell session to run other programs. You can then use fg to "foreground" your process again.