Drop IFF_POINTOPOINT from an address without a peer and compute an IPv4 broadcast address the host omits from the netmask, since FreeBSD always provides the address when the flag is set. Check zero port, flowinfo and padding in the test.
Return -1 with the FreeBSD errno for a null list and for expected host and allocation failures, as getcwd does. On Windows, give an unspecified prefix length a host mask, leave PPP and tunnel adapters without broadcast or point-to-point flags since their peer address is not reported, fall back to if<index> for long NDIS names, and bound the adapter query retries. Compare every entry with the host's own list in the test.
List the host's IPv4 and IPv6 addresses in FreeBSD's struct ifaddrs layout, with FreeBSD sockaddrs and interface flags, from getifaddrs on Linux and GetAdaptersAddresses on Windows. The list is one allocation, so freeifaddrs is a single free.
LuisBiceps