I want to integrate my app into the Unity/Ubuntu top panel by being able to output some small printed messages or icons or indicators to the panel. Some of my programs that I have installed do this, for example, Redshift has a button, and the gnome-system-indicator (system load indicator) outputs a CPU usage graph.
How can I access this programmatically, so that I can have my own program print data to the panel in the same way as something like gnome-system-indicator?