a #GDBusMessage
flags affecting how the message is sent
return location for serial number assigned to @message when sending it or %NULL
%TRUE if the message was well-formed and queued for transmission, %FALSE if @error is set
GException on failure.
2.26
Asynchronously sends @message to the peer represented by @connection.
Unless @flags contain the %G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL flag, the serial number will be assigned by @connection and set on @message via g_dbus_message_set_serial(). If @out_serial is not %NULL, then the serial number used will be written to this location prior to submitting the message to the underlying transport.
If @connection is closed then the operation will fail with %G_IO_ERROR_CLOSED. If @message is not well-formed, the operation fails with %G_IO_ERROR_INVALID_ARGUMENT.
See this server[gdbus-server] and client[gdbus-unix-fd-client] for an example of how to use this low-level API to send and receive UNIX file descriptors.
Note that @message must be unlocked, unless @flags contain the %G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL flag.