bind(2) issue (cont.)

Behavior is different between implementations
OpenBSD
w/o ipv4-mapped address
allows both sockets bound to same port number
ipv6 do not suck ipv4 traffic at all
NetBSD
w/ ipv4-mapped address
allows both sockets bound to same port number
ipv6 do not suck ipv4 traffic if ipv4 socket is not bound, and by default