`sig
type dispatch_status = Data_remains | Complete | Need_memory
val send : DBus.bus -> DBus.message -> int32
val send_with_reply : DBus.bus -> DBus.message -> int -> DBus.pending_call
val send_with_reply_and_block :
DBus.bus -> DBus.message -> int -> DBus.message
val add_filter : DBus.bus -> (DBus.bus -> DBus.message -> bool) -> unit
val flush : DBus.bus -> unit
val read_write : DBus.bus -> int -> bool
val read_write_dispatch : DBus.bus -> int -> bool
val pop_message : DBus.bus -> DBus.message option
val get_dispatch_status : DBus.bus -> DBus.Connection.dispatch_status
val dispatch : DBus.bus -> DBus.Connection.dispatch_status
val get_fd : DBus.bus -> Unix.file_descr
val set_watch_functions : DBus.bus -> DBus.watch_fns -> unit
val set_timeout_functions : DBus.bus -> DBus.timeout_fns -> unit
val get_max_message_size : DBus.bus -> int
val set_max_message_size : DBus.bus -> int -> unit
val get_max_received_size : DBus.bus -> int
val set_max_received_size : DBus.bus -> int -> unit
val get_outgoing_size : DBus.bus -> int
val set_allow_anonymous : DBus.bus -> bool -> unit
end`