The PRINTER_NOTIFY_INFO structure contains printer information returned by the FindNextPrinterChangeNotification function. The function returns this information after a wait operation on a printer change notification object has been satisfied.
typedef struct _PRINTER_NOTIFY_INFO {
DWORD Version;
DWORD Flags;
DWORD Count;
PRINTER_NOTIFY_INFO_DATA aData[1];
} PRINTER_NOTIFY_INFO;
If the Flags member has the PRINTER_NOTIFY_INFO_DISCARDED bit set, this indicates that an overflow or error occured, and notifications may have been lost. In this case, you must call FindNextPrinterChangeNotification and specify the PRINTER_NOTIFY_OPTIONS_REFRESH flag to retrieve all current information. Until you request this refresh operation, the system will not send additional notifications for this change notification object.