[This is preliminary documentation and subject to change.]
WBEM defines a set of system properties that are associated with all classes and instances of classes in addition to class-specific properties. As with system classes, system properties begin with a double underscore to differentiate them from properties created by applications or providers which may not start with a single or double underscore. Another way to identify a system property is by using the IWbemClassObject::Get method.
Not all system properties are available on all classes or instances at all times; the details of meaning and availability are specified separately for each property in the following table.
| Property | Type | Description |
|---|---|---|
| __Class | VT_BSTR | Class name. Available on all objects at all times. Read-only for instances; read/write for classes.. |
| __Derivation | VT_BSTR array | Class hierarchy of the current class or instance. Available on all objects at all times. The first element is the base-most class and the last element is the immediate superclass. |
| __Dynasty | VT_BSTR | Name of the top-level class from which this class or instance is derived. Available on all objects at all times and is read-only. When this class or instance is the top-level class, the values of __Dynasty and __Class are the same. |
| __Genus | VT_I4 | Used to distinguish between classes and instances. Available on all objects at all times. Read-only. Set to WBEM_GENUS_CLASS (1) for classes and WBEM_GENUS_INSTANCE (2) for instances. |
| __Namespace | VT_BSTR | Name of the namespace from which this class or instance came. Read-only. Available only on static objects provided by CIMOM; not available for dynamic objects such as those created through IWbemClassObject::SpawnInstance. |
| __Path | VT_BSTR | Full path to the class or instance, including server and namespace. Read-only. Available only on static objects provided by CIMOM; not available for dynamic objects such as those created through IWbemClassObject::SpawnInstance. |
| __Propertycount | VT_I4 | Number of non-system properties defined for the class or instance. Available on all objects at all times. Read-only. |
| __Relpath | VT_BSTR | Relative path to the class or instance. Available on all objects at all times. Read-only. |
| __Server | VT_BSTR | Name of the server supplying this class or instance. Read-only. Available only on static objects provided by CIMOM; not available for dynamic objects such as those created through IWbemClassObject::SpawnInstance. |
| __Superclass | VT_BSTR | Name of the immediate parent class of the class or instance. Available for all non-top-level classes and their instances. Read-only. |