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Module OBus_bus

module OBus_bus: sig .. end
Message buses management
type t = OBus_connection.t

Well-known instances

val session : ?switch:Lwt_switch.t -> unit -> t Lwt.t
session ?switch () returns a connection to the user session message bus. Subsequent calls to OBus_bus.session will return the same bus. OBus will automatically exits the program when an error happen on the session bus. You can change this behavior by calling OBus_connection.set_on_disconnect.
val system : ?switch:Lwt_switch.t -> unit -> t Lwt.t
system ?switch () returns a connection to the system message bus. As for OBus_bus.session, subsequent calls to OBus_bus.system will return the same bus. However, if the connection is closed or it crashes, OBus_bus.system will try to reopen it.

Creation

val of_addresses : ?switch:Lwt_switch.t -> OBus_address.t list -> t Lwt.t
Establish a connection with a message bus. The bus must be accessible with at least one of the given addresses
val register_connection : OBus_connection.t -> unit Lwt.t
Register the given connection to a message bus. It has the side effect of requesting a name to the message bus if not already done.

If the connection is a connection to a message bus, created with one of the function of OBus_connection then OBus_bus.register_connection must be called on it before any other functions.

val exit_on_disconnect : exn -> 'a
Function which exit the program as follow:



Peer/proxy helpers

val get_peer : t -> OBus_name.bus -> OBus_peer.t Lwt.t
get_peer bus name return the peer owning the bus name name. If the service is not activated and is activable, then it is started
val get_proxy : t -> OBus_name.bus -> OBus_path.t -> OBus_proxy.t Lwt.t
get_proxy bus name path resolve name with OBus_bus.get_peer and return a proxy for the object with path path on this service

Bus names

val name : t -> OBus_name.bus
Same as OBus_connection.name.
val names : t -> Set.Make(String).t React.signal
names bus is the signal holding the set of all names we currently own. It raises Invalid_argument if the connection is not a connection to a message bus.
val hello : t -> OBus_name.bus Lwt.t
hello connection sends an hello message to the message bus, which returns the unique connection name of the connection. Note that if the hello message has already been sent, it will fail.
exception Access_denied of string
Exception raised when a name cannot be owned due to security policies
type request_name_result = [ `Already_owner | `Exists | `In_queue | `Primary_owner ] 
val request_name : t ->
       ?allow_replacement:bool ->
       ?replace_existing:bool ->
       ?do_not_queue:bool -> OBus_name.bus -> request_name_result Lwt.t
Request a name to the bus. This is the way to acquire a well-know name.

All optionnal parameters default to false, their meaning are: 


type release_name_result = [ `Non_existent | `Not_owner | `Released ] 
val release_name : t -> OBus_name.bus -> release_name_result Lwt.t

Service starting/discovering

exception Service_unknown of string
Exception raised when a service is not present on a message bus and can not be started automatically
type start_service_by_name_result = [ `Already_running | `Success ] 
val start_service_by_name : t -> OBus_name.bus -> start_service_by_name_result Lwt.t
Start a service on the given bus by its name
val name_has_owner : t -> OBus_name.bus -> bool Lwt.t
Return true if the service is currently running, i.e. some application offer it on the message bus
val list_names : t -> OBus_name.bus list Lwt.t
List names currently running on the message bus
val list_activatable_names : t -> OBus_name.bus list Lwt.t
List services that can be activated. A service is automatically activated when you call one of its method or when you use start_service_by_name
exception Name_has_no_owner of string
val get_name_owner : t -> OBus_name.bus -> OBus_name.bus Lwt.t
Return the connection unique name of the given service. Raise a Name_has_no_owner if the given name does not have an owner.
val list_queued_owners : t -> OBus_name.bus -> OBus_name.bus list Lwt.t
Return the connection unique names of applications waiting for a name
exception Service_unknown of string
Raised when we try to contact a service which is not available and the bus do not known how to start it

Messages routing


Note that you should prefer using OBus_match.export and OBus_match.remove since they do not add duplicated rules several times.
exception Match_rule_invalid of string
Exception raised when the program try to send an invalid match rule. This should never happen since values of type OBus_match.rule are always valid.
val add_match : t -> OBus_match.rule -> unit Lwt.t
Add a matching rule on a message bus. This means that every message routed on the message bus matching this rule will be sent to us.

It can raise OBus_error.No_memory.

exception Match_rule_not_found of string
val remove_match : t -> OBus_match.rule -> unit Lwt.t
Remove a match rule from the message bus. It raises OBus_bus.Match_rule_not_found if the rule does not exists

Other


These functions are also offered by the message bus
exception Adt_audit_data_unknown of string
exception Selinux_security_context_unknown of string
val update_activation_environment : t -> (string * string) list -> unit Lwt.t
val get_connection_unix_user : t -> OBus_name.bus -> int Lwt.t
val get_connection_unix_process_id : t -> OBus_name.bus -> int Lwt.t
val get_adt_audit_session_data : t -> OBus_name.bus -> string Lwt.t
val get_connection_selinux_security_context : t -> OBus_name.bus -> string Lwt.t
val reload_config : t -> unit Lwt.t
val get_id : t -> OBus_uuid.t Lwt.t

Signals

val name_owner_changed : t -> (OBus_name.bus * OBus_name.bus * OBus_name.bus) OBus_signal.t
This signal is emited each time the owner of a name (unique connection name or service name) change.
val name_lost : t -> OBus_name.bus OBus_signal.t
val name_acquired : t -> OBus_name.bus OBus_signal.t