IBV_ATTACH_MCAST(3)     Libibverbs Programmer's Manual     IBV_ATTACH_MCAST(3)

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

SYNOPSIS
       #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);

DESCRIPTION
       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.

RETURN VALUE
       ibv_attach_mcast() and ibv_detach_mcast() returns 0 on success, or the
       value of errno on failure (which indicates the failure reason).

NOTES
       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.

SEE ALSO
       ibv_create_qp(3)

AUTHORS
       Dotan Barak <dotanba@gmail.com>

libibverbs                        2006-10-31               IBV_ATTACH_MCAST(3)