Listen for incoming connection requests.
(struct rdma_cm_id *id,
backlog of incoming connection requests.
Initiates a listen for incoming connection requests or datagram service
lookup. The listen will be restricted to the locally bound source
Returns 0 on success, or -1 on error. If an error occurs, errno will be
set to indicate the failure reason.
Users must have bound the rdma_cm_id to a local address by calling
rdma_bind_addr before calling this routine. If the rdma_cm_id is
bound to a specific IP address, the listen will be restricted to that
address and the associated RDMA device. If the rdma_cm_id is bound
to an RDMA port number only, the listen will occur across all RDMA