-*- nroff -*-
Licensed under the OpenIB.org BSD license (FreeBSD Variant) - See COPYING.md

ibv_attach_mcast, ibv_detach_mcast - attach and detach a queue pair (QPs) to/from a multicast group

 #include <infiniband/verbs.h>  "int ibv_attach_mcast(struct ibv_qp " "*qp" ", const union ibv_gid " "*gid" ",  " uint16_t " "lid" ");  "int ibv_detach_mcast(struct ibv_qp " "*qp" ", const union ibv_gid " "*gid" ",  " uint16_t " "lid" "); 

ibv_attach_mcast() attaches the QP qp to the multicast group having MGID gid and MLID lid.

ibv_detach_mcast() detaches the QP qp to the multicast group having MGID gid and MLID lid.

ibv_attach_mcast() and ibv_detach_mcast() returns 0 on success, or the value of errno on failure (which indicates the failure reason). Only QPs of Transport Service Type IBV_QPT_UD may be attached to multicast groups.

If a QP is attached to the same multicast group multiple times, the QP will still receive a single copy of a multicast message.

In order to receive multicast messages, a join request for the multicast group must be sent to the subnet administrator (SA), so that the fabric's multicast routing is configured to deliver messages to the local port.

ibv_create_qp (3)

Dotan Barak <dotanba@gmail.com>