typedef struct tagPDEVICE {
short pdType;
} PDEVICE;
The PDEVICE structure contains information that a graphics driver uses to identify a device and the current state of the device. The size and content of the structure depends entirely on the driver. For example, the structure may include the current pen, the current position, the communication port of a particular device, and other state information. However, the first member in every PDEVICE structure must be pdType.
pdType
Specifies the device type. If this member is nonzero, the structure identifies a device and all remaining members are driver specific. If this member is zero, the structure identifies a memory bitmap and all remaining members must be identical to a PBITMAP structure.
GDI allocates space for the PDEVICE structure when it calls the Enable func-tion to initialize a device driver. The size of this structure must be specified in the dpDEVICEsize member of the GDIINFO structure.