+/**
+ * Initiate an asynchronous PUT operation.
+ *
+ * There are several events associated with a PUT: completion of the send on
+ * the initiator node (LNET_EVENT_SEND), and when the send completes
+ * successfully, the receipt of an acknowledgment (LNET_EVENT_ACK) indicating
+ * that the operation was accepted by the target. The event LNET_EVENT_PUT is
+ * used at the target node to indicate the completion of incoming data
+ * delivery.
+ *
+ * The local events will be logged in the EQ associated with the MD pointed to
+ * by \a mdh handle. Using a MD without an associated EQ results in these
+ * events being discarded. In this case, the caller must have another
+ * mechanism (e.g., a higher level protocol) for determining when it is safe
+ * to modify the memory region associated with the MD.
+ *
+ * Note that LNet does not guarantee the order of LNET_EVENT_SEND and
+ * LNET_EVENT_ACK, though intuitively ACK should happen after SEND.
+ *
+ * \param self Indicates the NID of a local interface through which to send
+ * the PUT request. Use LNET_NID_ANY to let LNet choose one by itself.
+ * \param mdh A handle for the MD that describes the memory to be sent. The MD
+ * must be "free floating" (See LNetMDBind()).
+ * \param ack Controls whether an acknowledgment is requested.
+ * Acknowledgments are only sent when they are requested by the initiating
+ * process and the target MD enables them.
+ * \param target A process identifier for the target process.
+ * \param portal The index in the \a target's portal table.
+ * \param match_bits The match bits to use for MD selection at the target
+ * process.
+ * \param offset The offset into the target MD (only used when the target
+ * MD has the LNET_MD_MANAGE_REMOTE option set).
+ * \param hdr_data 64 bits of user data that can be included in the message
+ * header. This data is written to an event queue entry at the target if an
+ * EQ is present on the matching MD.
+ *
+ * \retval 0 Success, and only in this case events will be generated
+ * and logged to EQ (if it exists).
+ * \retval -EIO Simulated failure.
+ * \retval -ENOMEM Memory allocation failure.
+ * \retval -ENOENT Invalid MD object.
+ *
+ * \see lnet_event_t::hdr_data and lnet_event_kind_t.
+ */