gdkPropertyChange: gdkPropertyChange
In RGtk2: R Bindings for Gtk 2.8.0 and Above

Changes the contents of a property on a window.

1	gdkPropertyChange(object, property, type, format, mode, data)

`object`	a `GdkWindow`.
`property`	the property to change.
`type`	the new type for the property. If `mode` is `GDK_PROP_MODE_PREPEND` or `GDK_PROP_MODE_APPEND`, then this must match the existing type or an error will occur.
`format`	the new format for the property. If `mode` is `GDK_PROP_MODE_PREPEND` or `GDK_PROP_MODE_APPEND`, then this must match the existing format or an error will occur.
`mode`	a value describing how the new data is to be combined with the current data.
`data`	the data (a `guchar ` `gushort `, or `gulong `, depending on `format`), cast to a `guchar `.