QDFlushPortBuffer() has an optional region argument.

Mac/Modules/qd/Qdmodule.c

@@ -4802,7 +4802,7 @@ static PyObject *Qd_QDFlushPortBuffer(_self, _args)
 	RgnHandle region;
 	if (!PyArg_ParseTuple(_args, "O&O&",
 	                      GrafObj_Convert, &port,
-	                      ResObj_Convert, &region))
+	                      OptResObj_Convert, &region))
 		return NULL;
 	QDFlushPortBuffer(port,
 	                  region);

Mac/Modules/qd/qdscan.py

@@ -182,6 +182,10 @@ extend						= 0x40
 			 ([('RgnHandle', 'maskRgn', 'InMode')],
 			  [('OptRgnHandle', 'maskRgn', 'InMode')]),
 			  
+			 ('QDFlushPortBuffer',
+			  [('RgnHandle', '*', 'InMode')],
+			  [('OptRgnHandle', '*', 'InMode')]),
+			  
 			 # Accessors with reference argument also returned.
 			 ([('Rect_ptr', 'GetPortBounds', 'ReturnMode')],
 			  [('void', '*', 'ReturnMode')]),