typedef void(* MyQttOnReleaseMsg)(MyQttCtx *ctx, MyQttConn *conn, const char *client_identifier, int packaet_id, MyQttQos qos, unsigned char *app_msg, int app_msg_size, axlPointer user_data)

Optional handler that is called by the engine to notify a message is being released.

ctxThe context where the operation is taking place.
connThe connection where the operation is taking place.
client_identifierThe client identifier for which the message is being stored.
packet_idThe packet id associated to the message stored.
qosThe QoS for the message stored.
app_msgThe message requested to be stored.
app_msg_sizeThe message size to be stored.
user_dataUser defined pointer.
axl_true to allow message to be stored otherwise, axl_false must be returned to deny it.