Man pages matching name ibv_ack_cq_events in section 3:

ibv_ack_cq_events.3.en	debian 10 / libibverbs-dev
ibv_ack_cq_events.3.en	debian 11 / libibverbs-dev
ibv_ack_cq_events.3.en	debian 12 / libibverbs-dev