QPrintDialog is documented as supporting close() or done(int) methods, but neither have any effect when called.
The native dialog produced on Windows and Mac do not respond to these calls, and the QPrintDialog* is useless.

A sample application is attached which demonstrates that calling done() after QPrintDialog::open
does not close the dialog as documented. There does not appear to be any way to close the dialog
once it has been displayed without the user clicking Cancel or Print buttons.