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Occasionally, a client may wish to send or receive "Raw" packets--packets with the link and protocol headers attached. To send raw packets, the client merely sends them as M_DATA messages, as described in Fast Path Mode.
A client that wishes to receive raw packets may send an M_IOCTL message with the ioc_cmd field set to kOTSetRawMode and its chained data block containing a UInt32 value. The value can be either kOTRawRcvOn or kOTRawRcvOff, to turn on or off the reception of raw packets. If the driver supports the delivery of raw packets, it responds with an M_IOCACK message; otherwise, with an M_IOCNAK message.
Raw packets received will have the kaeRawPacketBit set in the dl_group_address field of the corresponding dl_unitdata_ind_t.