return
	}
	defer syscall.Closesocket(s)
	var optSupported = func(opt int) bool {
		err := syscall.SetsockoptInt(s, syscall.IPPROTO_TCP, opt, 1)
		return !errors.Is(err, syscall.WSAENOPROTOOPT)
	}
	supportTCPKeepAliveIdle = optSupported(TCP_KEEPIDLE)
	supportTCPKeepAliveInterval = optSupported(TCP_KEEPINTVL)
	supportTCPKeepAliveCount = optSupported(TCP_KEEPCNT)
})