One real-world example of Windows software that has support for AF_UNIX sockets is cURL. This patch allows cURL running under Wine to, for example, query `dockerd`:
$ wine curl.exe -s --unix-socket 'Z:/run/docker.sock' http://v1.42/version | jq -r .Version 23.0.6
Although it's not quite clear to me that ws2_32 is the right place to do that translation; we may want to do it in ntdll instead.
@zfigura Can you elaborate on this? I don't see a clean way of doing this in ntdll without modifying `struct afd_bind_params`, `struct afd_connect_params`, etc. to add a field for the Unix path, since none of the other `sock_ioctl` cases add on varargs.