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IWSDDeviceHost::SignalEvent method (wsdhost.h)

Notifies all subscribed clients that an event has occurred.

Syntax

HRESULT SignalEvent(
  [in] LPCWSTR             pszServiceId,
  [in] const void          *pBody,
  [in] const WSD_OPERATION *pOperation
);

Parameters

[in] pszServiceId

The ID of the service that generates the event.

[in] pBody

The body of the event.

[in] pOperation

Reference to a WSD_OPERATION structure that specifies the operation.

Return value

Possible return values include, but are not limited to, the following:

Return code Description
S_OK
 Method completed successfully.
E_FAIL
 The host is not started. Call Start to start the device host.
E_INVALIDARG
 pszServiceId is NULL, pOperation is NULL, the length in characters of pszServiceId exceeds WSD_MAX_TEXT_LENGTH (8192), there is no ResponseType structure associated with pOperation, or the service specified by pszServiceId is not subscribed to the event specified by the ResponseType member of pOperation.

Remarks

SignalEvent blocks until the event is sent to all clients. Since clients are contacted sequentially, it is possible that SignalEvent will block for a long time if any client responds slowly or is unreachable.

Requirements

Requirement Value
Minimum supported client Windows Vista [desktop apps only]
Minimum supported server Windows Server 2008 [desktop apps only]
Target Platform Windows
Header wsdhost.h (include Wsdapi.h)
DLL Wsdapi.dll

See also

IWSDDeviceHost