Old RCS, 2010-02-25 15:15 UTC: User interface stuff:

- remove -sync, which does nothing (inherited from xxscope)
- Add -o, which puts output in a named file
- Add -split, which puts each connection's output in its own file
- Add -fork, which causes it to fork-and-exit once startup succeeds
- Add -pid, which makes it print its PID
- Add -idle, which makes it exit as soon as it has no live connections
   once it has ever had a live connection.

-fork, -pid, and -hunt play nice together; if -hunt and -pid are both
used, -hunt output appears first.  -pid and -hunt are specifically
designed to work well with shell backquotes; if output is going to
a file (or files, with -split), stdout is closed once -pid and/or
-hunt output has been printed.