For my sins, I have dabbled in writing netcat-like programs for sometime, things that take standard input, send it off to somewhere over thenetwork, and write to standard out what they get back from the network.In the process I have formed very definite opinions about how theseprograms should behave in order to be most useful (in scripts and so on),and I feel like writing it down.

For the most part, a network copying program is straightforward; you use select() or