GtkWidget->window

[Russell Shaw <rjshaw iprimus com au>]

Hi,
I've been studying the drawing example:
  http://www.gtk.org/tutorial/sec-scribble.html#AEN2945

In the function below, GtkWidget has a member "window".
I can't find this member anywhere in the online help:
  http://developer.gnome.org/doc/API/2.0/gtk/GtkWidget.html

Do developers regularly search the gtk sources for this kind
of thing, or is the online help supposed to be enough?

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/* Create a new backing pixmap of the appropriate size */
static gboolean configure_event( GtkWidget         *widget,
                                 GdkEventConfigure *event )
{
  if (pixmap)
    g_object_unref (pixmap);

  pixmap = gdk_pixmap_new (widget->window,
                           widget->allocation.width,
                           widget->allocation.height,
                           -1);
  gdk_draw_rectangle (pixmap,
                      widget->style->white_gc,
                      TRUE,
                      0, 0,
                      widget->allocation.width,
                      widget->allocation.height);

  return TRUE;
}