fi_mr(3) on Linux
The text 8edb557bb956, as Debian 9 (Stretch) shipped it.
Memory region operations fi_mr_reg / fi_mr_regv / fi_mr_regattr : Register local memory buffers for direct fabric access fi_close : Deregister registered memory buffers. fi_mr_desc : Return a local descriptor associated with a registered memory region fi_mr_key : Return the remote key needed to access a registered memory region fi_mr_bind : Associate a registered memory region with a completion counter.