You can search for identifiers within the package.
in-package search v0.2.0
type 'a io = 'a Lwt.t
type buffer = Cstruct.t
type id = int
type macaddr = Macaddr.t
type t
val register : t -> (id, Mirage_net.Net.error) result
val unregister : t -> id -> unit io
val mac : t -> id -> macaddr
val write : t -> id -> size:int -> (buffer -> int) -> (unit, Mirage_net.Net.error) result io
val set_listen_fn : t -> id -> (buffer -> unit io) -> unit
val unregister_and_flush : t -> id -> unit io