Subscribes to signals on this and invokes
callback with a whenever the signal is received.
callback will be invoked in the thread-default main context of the thread you are calling this method from.
If this is not a message bus connection,
sender must be null.
sender is a well-known name note that
callback is invoked with the unique name for the owner of
, not the well-known name as one would expect. This is because the message bus rewrites the name. As such, to avoid certain race
conditions, users should be tracking the name owner of the well-known name and use that when processing the received signal.
If one of g_dbus_signal_flags_match_arg0_namespace or
g_dbus_signal_flags_match_arg0_path are given,
arg0 is interpreted as part of a namespace or path. The first argument of a
signal is matched against that part as specified by D-Bus.
user_data_free_func is non-null, it will be called (in the thread-default main context of the
thread you are calling this method from) at some point after
user_data is no longer needed. (It is not guaranteed to be called
synchronously when the signal is unsubscribed from, and may be called after this has been destroyed.)
The returned subscription identifier is an opaque value which is guaranteed to never be zero.
This function can never fail.
sender name to match on (unique or well-known name) or null to listen from all senders
D-Bus interface name to match on or null to match on all interfaces
D-Bus signal name to match on or null to match on all signals
object path to match on or null to match on all object paths
contents of first string argument to match on or null to match on all kinds of arguments
DBusSignalFlags describing how arg0 is used in subscribing to the signal
callback to invoke when there is a signal matching the requested data
user data to pass to
function to free
a subscription identifier that can be used with signal_unsubscribe