16- to 32-Bit Thunks in GDI Device Drivers

In a GDI device driver, you can use only the following control display driver interface (DDI) functions:

• Control(ABORTDOC)
• Control(ENDDOC)
• Control(NEWFRAME)
• Control(NEXTBAND)
• Control(STARTDOC)

If you use thunking, your driver must be reentrant. You must also use the following compatibility statement in the thunk script:

win31compat = true; 
 

You can call the OpenJob, StartSpoolPage, EndSpoolPage, CloseJob, and DeleteJob functions during the five listed control DDI calls. These calls are by drivers written for Windows version 3.x to support backward compatibility, but they will not be handled by Windows 95–based drivers.