public static string GetString(int socket, SocketOptionLevel level, SocketOption opts)
{
string value = null;
int size = 0;
int result = Interop.nn_getsockopt_string(socket, (int)level, (int)opts, ref value, ref size);
if (result != 0)
{
throw new NanomsgException(string.Format("nn_getsockopt {0}", opts));
}
return(value);
}