The man page (and usage message) for ifconfig on 3.8-beta seems to
be out of date with respect to the current behavior when deleting
a tunnel.
# ifconfig tun0 create
# ifconfig tun0
tun0: flags=10<POINTOPOINT> mtu 3000
groups: tun
# ifconfig tun0 10.0.0.1 10.0.0.2
# ifconfig tun0
tun0: flags=51<UP,POINTOPOINT,RUNNING> mtu 3000
groups: tun
inet 10.0.0.1 --> 10.0.0.2 netmask 0xff000000
# #NOTE: deletetunnel doesn't work
# ifconfig tun0 deletetunnel
ifconfig: SIOCDIFPHYADDR: Invalid argument
# #NOTE: but delete does
# ifconfig tun0 delete
# ifconfig tun0
tun0: flags=51<UP,POINTOPOINT,RUNNING> mtu 3000
groups: tun
# ifconfig tun0 destroy
# ifconfig tun0
tun0: no such interface
#
