Listen(port=0) - htons the port copied to the next addrinfo#183
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When Listen(port=0) resolves to multiple addrinfos (typically IPv6 + IPv4) the first listener binds an ephemeral port, then that port is copied into the next addrinfo's sin_port so all listeners share it. But sin_port is in network byte order, while LListen.LocalPort is host order (the integer parsed out of getnameinfo's NI_NUMERICSERV string in TSocketAPI.ExtractAddrInfo), so without htons() the second listener binds a byte-swapped port -- the dual-stack port-0 listen no longer shares the port. Fixed in all three backends (Kqueue/Epoll/Iocp). The Connect paths in the same units already use htons(ALocalPort), confirming intent.
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When Listen(port=0) resolves to multiple addrinfos (typically IPv6 + IPv4) the first listener binds an ephemeral port, then that port is copied into the next addrinfo's sin_port so all listeners share it. But sin_port is in network byte order, while LListen.LocalPort is host order (the integer parsed out of getnameinfo's NI_NUMERICSERV string in TSocketAPI.ExtractAddrInfo), so without htons() the second listener binds a byte-swapped port -- the dual-stack port-0 listen no longer shares the port.
Fixed in all three backends (Kqueue/Epoll/Iocp). The Connect paths in the same units already use htons(ALocalPort), confirming intent.