C-C++ Code Example: Retrieving PROPID_Q_PRIV_LEVEL

Applies To: Windows 10, Windows 7, Windows 8, Windows 8.1, Windows Server 2008, Windows Server 2008 R2, Windows Server 2012, Windows Server 2012 R2, Windows Server Technical Preview, Windows Vista

This example provides an application-defined function that retrieves the PROPID_Q_PRIV_LEVEL property of an existing queue and returns the privacy level to the caller.

This function can return the privacy level of a local private queue from information stored on the local computer, but must retrieve information stored in the directory service to return the privacy level of a local or remote public queue. This function cannot be used to obtain the privacy level of a remote private queue.

A direct format name can be passed to this function only for a local private queue.

For information on how Message Queuing encrypts messages, see Message Encryption.

To retrieve PROPID_Q_PRIV_LEVEL

1. Define the maximum number of queue properties to be specified and the queue property counter.

2. Define the MQQUEUEPROPS structure.

3. Specify PROPID_Q_JOURNAL.

4. Initialize the MQQUEUEPROPS structure.

5. Validate the input parameters provided by the caller.

6. Call MQGetQueueProperties to retrieve the privacy level of the queue. If the call fails the returned error code is returned to the caller.

7. Pass the retrieved privacy level of the queue to the caller on return.

Code Example

The following code example can be run on all versions of Message Queuing.

HRESULT GetQueuePrivLevelProp(  
                              LPCWSTR wszQueueFormatName,   
                              ULONG *pulValue  
                              )  
{  
  
  // Define the maximum number of queue properties and a property counter.  
  const int NUMBEROFPROPERTIES = 1;  
  DWORD cPropId = 0;  
  
  // Define a queue property structure.  
  MQQUEUEPROPS   QueueProps;  
  QUEUEPROPID    aQueuePropId[NUMBEROFPROPERTIES];  
  MQPROPVARIANT  aQueuePropVar[NUMBEROFPROPERTIES];  
  HRESULT        aQueuePropStatus[NUMBEROFPROPERTIES];  
  HRESULT hr = MQ_OK;  
  
  // Specify the PROPID_Q_PRIV_LEVEL property.  
  aQueuePropId[cPropId] = PROPID_Q_PRIV_LEVEL;    // Property ID  
  aQueuePropVar[cPropId].vt = VT_NULL;            // Type indicator  
  cPropId++;  
  
  // Initialize the MQQUEUEPROPS structure.  
  QueueProps.cProp = cPropId;  
  QueueProps.aPropID = aQueuePropId;  
  QueueProps.aPropVar = aQueuePropVar;  
  QueueProps.aStatus = aQueuePropStatus;  
  
  // Validate the input parameters.  
  if (wszQueueFormatName == NULL || pulValue == NULL)  
  {  
    return MQ_ERROR_INVALID_PARAMETER;  
  }  
  
  // Get the queue properties.  
  hr = MQGetQueueProperties(wszQueueFormatName, &QueueProps);  
  if (FAILED(hr))  
  {  
    return hr;  
  }  
  
  // Set the *pulValue parameter to pass the privacy level of the queue on return.  
  *pulValue = aQueuePropVar[0].ulVal;  
  return hr;  
}