dbus-register-method is a compiled Lisp function in `
(dbus-register-method BUS SERVICE PATH INTERFACE METHOD HANDLER &optional DONT-REGISTER-SERVICE)
Register for method METHOD on the D-Bus BUS.
BUS is either a Lisp symbol, `:system' or `:session', or a string
denoting the bus address.
SERVICE is the D-Bus service name of the D-Bus object METHOD is
registered for. It must be a known name (See discussion of
PATH is the D-Bus object path SERVICE is registered (See discussion of
DONT-REGISTER-SERVICE below). INTERFACE is the interface offered by
SERVICE. It must provide METHOD.
HANDLER is a Lisp function to be called when a method call is
received. It must accept the input arguments of METHOD. The return
value of HANDLER is used for composing the returning D-Bus message.
In case HANDLER shall return a reply message with an empty argument
list, HANDLER must return the symbol `:ignore'.
When DONT-REGISTER-SERVICE is non-nil, the known name SERVICE is not
registered. This means that other D-Bus clients have no way of
noticing the newly registered method. When interfaces are constructed
incrementally by adding single methods or properties at a time,
DONT-REGISTER-SERVICE can be used to prevent other clients from
discovering the still incomplete interface.