flush
Asynchronously flushes @connection, that is, writes all queued outgoing message to the transport and then flushes the transport (using g_output_stream_flush_async()). This is useful in programs that wants to emit a D-Bus signal and then exit immediately. Without flushing the connection, there is no guaranteed that the message has been sent to the networking buffers in the OS kernel.
This is an asynchronous method. When the operation is finished,
Since
2.26
Parameters
cancellable
a #GCancellable or null
callback
a #GAsyncReadyCallback to call when the request is satisfied or null if you don't care about the result