IWbemServices Interface (Windows)

IWbemServices Interface

The IWbemServices interface is used by clients and providers to access WMI services. The interface is implemented by WMI and WMI providers, and is the primary WMI interface.

    IWbemClassObject *pObj = NULL;

    //The pWbemSvc pointer is of type IWbemServices*
    pWbemSvc->GetObject(L"path", 0, 0, &pObj, 0);

Methods

The IWbemServices interface inherits the methods of the IUnknown interface.

In addition, IWbemServices defines the following methods.

Method	Description
OpenNamespace	Opens a specific child namespace for operations.
CancelAsyncCall	Cancels a currently executing asynchronous call.
QueryObjectSink	Allows a caller to obtain a notification handler sink.
GetObject	Retrieves an object—an instance or class definition.
GetObjectAsync	Asynchronously retrieves an object—an instance or class definition.
PutClass	Creates or updates a class definition.
PutClassAsync	Asynchronously creates or updates a class definition.
DeleteClass	Deletes a class.
DeleteClassAsync	Deletes a class and receives confirmation asynchronously.
CreateClassEnum	Creates a class enumerator.
CreateClassEnumAsync	Creates a class enumerator that executes asynchronously.
PutInstance	Creates or updates an instance of a specific class.
PutInstanceAsync	Asynchronously creates or updates an instance of a specific class.
DeleteInstance	Deletes a specific instance of a class.
DeleteInstanceAsync	Deletes an instance and provides confirmation asynchronously.
CreateInstanceEnum	Creates an instance enumerator.
CreateInstanceEnumAsync	Creates an instance enumerator that executes asynchronously.
ExecQuery	Executes a query to retrieve classes or instances.
ExecQueryAsync	Executes a query to retrieve classes or instances asynchronously.
ExecNotificationQuery	Executes a query to receive events.
ExecNotificationQueryAsync	Executes a query to receive events asynchronously.
ExecMethod	Executes an object method.
ExecMethodAsync	Executes an object method asynchronously.

Remarks

Providers that implement the IWbemServices interface must follow the documented semantics of each method that they implement; and providers must support the specified error return codes. WMI implements all of the methods, and typically, each provider implements a small subset of the available functionality on the interface. Providers must return WBEM_E_PROVIDER_NOT_CAPABLE for any method that they do not implement.

All outbound interface pointers from any IWbemServices method should be initialized to NULL before calling the interface method. For example, calls to the IWbemServices::GetObject method return an IWbemClassObject interface pointer that should be pre-initialized to NULL before the IWbemServices::GetObject method call.

Examples

The following code example shows how a provider can get an IWbemServices pointer. The code requires the following #include statements and references to compile.

#include <iostream>
using namespace std;
#include <wbemidl.h>
# pragma comment(lib, "wbemuuid.lib")

IWbemLocator *pIWbemLocator = NULL;

HRESULT hRes = CoCreateInstance (
            CLSID_WbemAdministrativeLocator,
            NULL ,
            CLSCTX_INPROC_SERVER | CLSCTX_LOCAL_SERVER , 
            IID_IUnknown ,
            ( void ** ) &pIWbemLocator
            ) ;

IWbemServices *pWbemServices = NULL;

if (SUCCEEDED(hRes))
{
    hRes = pIWbemLocator->ConnectServer(
                L"root\\CIMV2",  // Namespace
                NULL,          // Userid
                NULL,           // PW
                NULL,           // Locale
                0,              // flags
                NULL,           // Authority
                NULL,           // Context
                &pWbemServices
                );

pIWbemLocator->Release(); // Free memory resources.

// Use pWbemServices

}

// Clean up
pWbemServices->Release();

Requirements

Minimum supported client	Windows 2000 Professional
Minimum supported server	Windows 2000 Server
Header	Wbemcli.h (include Wbemidl.h)
Library	Wbemuuid.lib
DLL	Fastprox.dll, Esscli.dll, Framedyn.dll, Ntevt.dll, Stdprov.dll, Viewprov.dll, Wbemcomn.dll, Wbemcore.dll, Wbemess.dll, Wbemsvc.dll, Wmipicmp.dll, Wmidcprv.dll, Wmipjobj.dll, Wmiprvsd.dll

Methods

Remarks

Examples

Requirements

See Also