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wiasQueueEvent function (wiamdef.h)

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The wiasQueueEvent function informs the service that the device generated an event.

Syntax

HRESULT wiasQueueEvent(
  [in]           BSTR       bstrDeviceId,
  [in]           const GUID *pEventGUID,
  [in, optional] BSTR       bstrFullItemName
);

Parameters

[in] bstrDeviceId

Specifies the device ID. This is the value passed to the minidriver in the call to the IWiaMiniDrv::drvInitializeWia method.

[in] pEventGUID

Pointer to a buffer that contains the GUID for the event.

[in, optional] bstrFullItemName

Specifies the full item name, including path information.

Return value

On success, the function returns S_OK.

If the function fails, it returns a standard COM error or one of the WIA error codes.

Remarks

This method should be used whenever the device must signal that an event of some type occurred. The device does this by placing the event on the event queue. For example, when a camera takes a new picture, it should generate a WIA_EVENT_ITEM_CREATED event after adding a new driver item to its tree. The camera can place this event on the event queue in this way:

hr = wiasQueueEvent(bstrMyDeviceId,
                    &WIA_EVENT_ITEM_CREATED,
                    bstrDescriptionString);

See the Windows SDK documentation for a complete list of WIA event identifiers.

Requirements

Requirement Value
Target Platform Desktop
Header wiamdef.h (include Wiamdef.h)
Library Wiaservc.lib
DLL Wiaservc.dll

See also

IWiaMiniDrv::drvInitializeWia