title: Find all open windows for a process in GTK
body: <p>Is there anyway in GTK to get all of the current windows open by a specific process? Ideally, I'd like to be able to get the GtkWindow instances. I know Java AWT has this:</p>
  
  <pre><code>java.awt.Window[] windows = java.awt.Window.getWindows();
  </code></pre>
  
  <p>And Microsoft's UI Automation also has a way to get all of the windows for an application. Is there anyway to do this with GTK?</p>
  
  <p>I found a function gtk_window_list_toplevels, but it seems to return way too many windows. The application gedit has 30 top-level windows on my computer. That just seems to be too many for an application with one window.</p>