package vchan

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include S.EVENTS
type port

an identifier for a source of events. Ports are allocated by calls to listen, then exchanged out-of-band (typically by xenstore) and finally calls to connect creates a channel between the two domains. Events are send and received over these channels.

val sexp_of_port : port -> Sexplib0.Sexp.t
val port_of_string : string -> (port, [> `Msg of string ]) result
val string_of_port : port -> string
type channel

a channel is the connection between two domains and is used to send and receive events.

val sexp_of_channel : channel -> Sexplib0.Sexp.t
type event

an event notification received from a remote domain. Events contain no data and may be coalesced. Domains which are blocked will be woken up by an event.

val sexp_of_event : event -> Sexplib0.Sexp.t
val initial : event

represents an event which 'fired' when the program started

val recv : channel -> event -> event Lwt.t

recv channel event blocks until the system receives an event newer than event on channel channel. If an event is received while we aren't looking then this will be remembered and the next call to after will immediately unblock. If the system is suspended and then resumed, all event channel bindings are invalidated and this function will fail with Generation.Invalid

val send : channel -> unit

send channel sends an event along channel, to another domain which will be woken up

val listen : int -> port * channel

listen domid allocates a fresh port and event channel. The port may be supplied to connect

val connect : int -> port -> channel

connect domid port connects an event channel to port on domid

val close : channel -> unit

close channel closes this side of an event channel

val assert_cleaned_up : unit -> unit

Throws a Failure if there are any resources still in use. This is intended to be used by test cases to check everything has been properly closed.