Default to IPv6 bind address

[belohnung]

Default to IPv6 bind address

• By default applications should listen to the ipv6 wildcard address as this also includes IPv4 addresses and enables IPv6 support

Solution

• The default bind ip address was set to the UNSPECIFIED constant of IPv6Adress

[dyc3]

IIRC, this port binding behavior is only applicable to Linux. Does it do the same thing on Windows and Mac?

[dyc3]

It appears that on windows, this PR will make it so that it only binds to ipv6, and not both.

Source: https://learn.microsoft.com/en-us/windows/win32/winsock/dual-stack-sockets#creating-a-dual-stack-socket

[belohnung]

My bad. Could we set those sock opts so that the behavior matches?

[dyc3]

You tell me, this is your PR.

[belohnung]

It really sucks that the behavior is not uniform. With a quick search i also did not find a way to set a sockopt on the TcpListener.. Perhaps we could default to IPv6 on Linux only for now?

[dyc3]

I think you could create a std::net::TcpListener to set up the socket then use https://docs.rs/tokio/latest/tokio/net/struct.TcpListener.html#method.from_std to turn it into a tokio socket.

this might also help: https://docs.rs/net2/latest/net2/struct.TcpBuilder.html#method.only_v6