internal enum AI : int
internal enum AI
    {
    /// <summary>
    /// The socket address will be used in a call to the bind function.
    /// </summary>
    AI_PASSIVE = 0x01,
    /// <summary>
    /// The canonical name is returned in the first ai_canonname member.
    /// </summary>
    AI_CANONNAME = 0x02,
    /// <summary>
    /// The nodename parameter passed to the getaddrinfo function must be a numeric string.
    /// </summary>
    AI_NUMERICHOST = 0x04,
    /// <summary>
    /// The getaddrinfo will resolve only if a global address is configured. The IPv6 and IPv4 loopback address is not considered a valid global address. This option is only supported on Windows Vista or later.
    /// </summary>
    AI_ADDRCONFIG = 0x0400,
    /// <summary>
    /// The address information can be from a non-authoritative namespace provider. This option is only supported on Windows Vista or later for the NS_EMAIL namespace.
    /// </summary>
    AI_NON_AUTHORITATIVE = 0x04000,
    /// <summary>
    /// The address information is from a secure channel. This option is only supported on Windows Vista or later for the NS_EMAIL namespace.
    /// </summary>
    AI_SECURE = 0x08000,
    /// <summary>
    /// The address information is for a preferred name for a user. This option is only supported on Windows Vista or later for the NS_EMAIL namespace.
    /// </summary>
    AI_RETURN_PREFERRED_NAMES = 0x010000,
    /// <summary>
    /// A hint to the namespace provider that the hostname being queried is being used in file share scenario. The namespace provider may ignore this hint.
    /// </summary>
    AI_FILESERVER = 0x00040000
    AI_FILESERVER = 0x00040000,
    }