1) Make fetch_mode a pointer 'cos we can just use the optarg.
2) Constness.
3) Add/complete prototypes.
4) Change an int to a socklen_t.
5) Don't use C++ style comments.
6) Check return values from read and fork a little more carefully.
7) Avoid closing an uninitialised int.
8) Get rid of unneeded extern declarations.
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