Most of these tests are required to be run as root.
(Addendum by Marco Carnut: the root user check is disabled when
running on Cygwin with winpcap)

Note that some of these tests require a working network interface with
actual traffic on it.  For example the loop test waits for 10 packets
to be received on the network before exiting.  If there is no traffic
on the interface, this test will block.

The memory leak tests do not complete.
