typedef struct OpaquePMPageFormat* PMPageFormat;
Your application uses the function PMNewPageFormat to create an instance of this opaque object. When your application displays a page setup dialog box by calling PMPageSetUpDialog or PMPageSetUpDialogMain, the user can change these settings, which the Carbon Printing Manager saves in the PMPageFormat object.
Although a PMPrintSettings object can be saved with a document, the object is intended to describe only one particular printing session.
A PMPageFormat object can be saved along with a document to provide some persistence on how documents are printed.