Creating a window with attributes on Mac with NewCWindow

I want to create a window on Mac with kWindowCompositingAttribute. Windows in my code are using NewCWindow (and not CreateNewWindow) (legacy code).

Before I jump on to CreateNewWindow, I wanted to check if there is some way to enable this attribute using NewCWind开发者_开发问答ow().

The docs on kHIWindowBitCompositing say "This attribute must be specified at window creation; you may not add this attribute after the window has been created." so I'd say the answer is no.