ICluster::get_EnvironmentVariables method

Retrieves the cluster-wide environment variables. The variables are available to all tasks on all nodes.

Syntax

HRESULT get_EnvironmentVariables(
  [out] INameValueCollection **pRetVal
);

Parameters

• pRetVal [out]
  An INameValueCollection interface that contains the collection of environment variables. The variant type of each item in the collection is VT_DISPATCH. Query the pdispVal member of the variant for the INameValue interface.

Return value

If the method succeeds, the return value is S_OK. Otherwise, the return value is an error code. To get a description of the error, call the ICluster::get_ErrorMessage method.

Remarks

To set a cluster-wide environment variable, call the ICluster::SetEnvironmentVariable method. To set an environment variable that is available to a specific task, call the ITask::SetEnvironmentVariable method.

Examples

The following example shows how to call this method. The example assumes the pCluster parameter points to a valid ICluster interface.

void ListClusterEnvironmentVariables(ICluster* pCluster)
{
  HRESULT hr = S_OK;
  INameValueCollection* pCollection = NULL;
  INameValue* pVariable = NULL;
  IEnumVARIANT* pVariables = NULL;
  long count = 0;
  BSTR bstrClusterName = NULL;
  BSTR bstrVariableName = NULL;
  BSTR bstrVariableValue = NULL;
  VARIANT var;

  hr = pCluster->get_EnvironmentVariables(&pCollection);
  if (FAILED(hr))
  {
    wprintf(L"pCluster->get_EnvironmentVariables failed.\n");
    return;
  }

  hr = pCollection->GetEnumerator(&pVariables);
  if (FAILED(hr))
  {
    wprintf(L"pCollection->GetEnumerator failed.\n");
    goto cleanup;
  }

  hr = pCollection->get_Count(&count);
  if (FAILED(hr))
  {
    wprintf(L"pCollection->get_Count failed.\n");
    goto cleanup;
  }

  hr = pCluster->get_Name(&bstrClusterName);
  if (FAILED(hr))
  {
    wprintf(L"pCluster->get_Name failed.\n");
    goto cleanup;
  }

  wprintf(L"\nThe following lists the %d environment variable for the cluster, %s:\n", count, bstrClusterName);

  VariantInit(&var);

  while (hr = pVariables->Next(1, &var, NULL) == S_OK)
  {
    var.pdispVal->QueryInterface(IID_INameValue, reinterpret_cast<void **> (&pVariable));

    hr = pVariable->get_Name(&bstrVariableName);
    if (SUCCEEDED(hr))
    {
      wprintf(L"\nName: %s\n", bstrVariableName);
      SysFreeString(bstrVariableName);

      hr = pVariable->get_Value(&bstrVariableValue);
      if (SUCCEEDED(hr))
      {
        wprintf(L"Value: %s\n", bstrVariableValue);
        SysFreeString(bstrVariableValue);
      }
      else
      {
        wprintf(L"Failed to get variable value.\n");
      }
    }
    else
    {
      wprintf(L"Failed to get variable name.\n");
    }

    pVariable->Release();
    pVariable = NULL;

    VariantClear(&var);
  }

cleanup:

  if (pCollection)
    pCollection->Release();

  if (pVariables)
    pVariables->Release();

  SysFreeString(bstrClusterName);

  return;
}

Requirements

See also

ICluster

ITask::SetEnvironmentVariable