Description

The print spooler's ReplyPrinterChangeNotification function allows a print provider to update the spooler's database of print queue events associated with a notification handle, and to notify the client that print queue events have occurred.

Parameters

hPrinter

Caller-supplied handle. This handle must have been previously received as the hNotify input to the print provider's FindFirstPrinterChangeNotification function.

fdwChangeFlags

One or more caller-supplied PRINTER_CHANGE_-prefixed flags, listed in the Microsoft Windows SDK documentation's description of FindNextPrinterChangeNotification.

pdwResult [out, optional]

Optional. If not NULL, it receives spooler-supplied PRINTER_NOTIFY_INFO-prefixed flags indicating results of updating the supplied information.

pPrinterNotifyInfo [in, optional]

Optional. Caller-supplied address of a PRINTER_NOTIFY_INFO structure (described in the Windows SDK documentation). Can be NULL if no new notification information is being added.

Return value

If the operation succeeds, the function returns TRUE. Otherwise the function returns FALSE. The caller can obtain an error code by calling GetLastError.

Remarks

Print providers that do not support polling (see FindFirstPrinterChangeNotification) must notify the spooler of the occurrence of any events represented by the PRINTER_CHANGE_-prefixed flags received by the provider's FindFirstPrinterChangeNotification function. When an event occurs, the print provider can call ReplyPrinterChangeNotification to inform the spooler of the event and to supply information associated with the event. The spooler keeps track of this event information, for each notification handle, and delivers the information to an application when the application calls FindNextPrinterChangeNotification (described in the Windows SDK documentation).

When a print provider calls ReplyPrinterChangeNotification, it must identify the event that has occurred by setting a PRINTER_CHANGE_-prefixed flag in fwdFlags or by using pPrinterNotifyInfo to return a PRINTER_NOTIFY_INFO structure. (Use the flags listed in the Windows SDK documentation's description of FindNextPrinterChangeNotification--not the flags listed in the Windows SDK documentation's description of FindFirstPrinterChangeNotification.)

Calling ReplyPrinterChangeNotification causes the spooler to signal the client application that a print queue event has occurred. This happens even if the provider supplies NULL for pPrinterNotifyInfo. To update the spooler's record of print queue changes without causing the client to be notified, use PartialReplyPrinterChangeNotification. It is common to call PartialReplyPrinterChangeNotification several times to update the spooler's database, then to call ReplyPrinterChangeNotification to notify the client that changes have occurred.

For additional information, see Supporting Printer Change Notifications.

See also

FindFirstPrinterChangeNotification

PartialReplyPrinterChangeNotification