int silc_net_udp_send(SilcStream stream,
                          const char *remote_ip_addr, int remote_port,
                          const unsigned char *data, SilcUInt32 data_len);

    Sends an UDP packet to remote host `remote_ip_addr' on `remote_port'.
    This may be used with UDP streams that are not connected to any
    specific remote host.  With those stream silc_stream_write cannot be
    used.  In those cases, this function must be used.  This may also be
    used even if the stream is connected.

    Returns the amount of data written, -1 if data could not be written
    at this moment, or -2 if error occurred.  If -1 is returned the
    notifier callback will later be called with SILC_STREAM_CAN_WRITE
    status when stream is again ready for writing.