!wudfext.wudfobject

The !wudfext.wudfobject extension displays information about a WDF object, as well as its parent and child relationships.

Syntax

!wudfext.wudfobject pWDFObject [Flags] [TypeName] 

Parameters

pWDFObject

Specifies the address of the WDF interface to display information about.

Flags

Optional. Specifies the type of information to be displayed. Flags can be any combination of the following bits. The default value is 0x01.

Bit 0 (0x01)

Steps through the object hierarchy to obtain the parent and child relationships.

Bit 1 (0x02)

Displays only summary information about the object.

Bit 8 (0x80)

Displays details about the internal framework.

TypeName

Optional. Specifies the type of the interface (for example, IWDFDevice). If a value for TypeName is provided, !wudfext.wudfobject uses the value as the type of the interface. If a value for TypeName is not provided or if an asterisk (*) is provided, !wudfext.wudfobject attempts to automatically determine the type of the supplied interface.

DLL

Comments

You can use !wudfext.wudfobject to list, for example, the child objects of an IWDFDevice object, which generally include the device’s queues.

You can also use !wudfext.wudfobject to find WDF objects that are associated with a particular device, to check the state of a WDF object (for example, whether the WDF object is in the process of deletion), or to determine the WDF object’s current reference count.

The !wudfext.wudfobject extension also displays the callback functions and context objects that the driver associated with each framework object and attempts to determine the framework object's type. This last feature might not work with certain compilers.

The following are some examples of the !wudfext.wudfobject display:

• kd> !wudfobject 0xf2f80
  IWDFDevice 0xf2f80 Fx: 0xf2f08 [Ref 2]
  Callback: (??, 0xf2c50)
    State: Created   Parent: 0xf2db8
    5 Children:
      00: IWDFIoTarget 0xf33c0 Fx: 0xf3348 [Ref 3]
      01: IWDFIoQueue 0xf3500 Fx: 0xf3488 [Ref 3]
      02: IWDFFile 0xf5060 Fx: 0xf4fe8 [Ref 1]
      03: IWDFFile 0xf5100 Fx: 0xf5088 [Ref 101]
      04: IWDFFile 0xf51a0 Fx: 0xf5128 [Ref 101]
  
  

• kd> !wudfobject 0xf5060
  IWDFFile 0xf5060 Fx: 0xf4fe8 [Ref 1]
    State: Created   Parent: 0xf2f80
    No Children
  
  

• kd> !wudfobject 0xf2db8 0x01
  IWDFDriver 0xf2db8 Fx: 0xf2d40 [Ref 2]
    Callback: (WUDFEchoDriver!CMyDriver, 0xf2c68)
    State: Created   Parent: 0
    1 Children:
      00: IWDFDevice 0xf2f80 Fx: 0xf2f08 [Ref 2]
          State: Created   Parent: 0xf2db8
          5 Children:
            00: IWDFIoTarget 0xf33c0 Fx: 0xf3348 [Ref 3]
                State: Created   Parent: 0xf2f80
                No Children
            01: IWDFIoQueue 0xf3500 Fx: 0xf3488 [Ref 3]
                State: Created   Parent: 0xf2f80
                No Children
            02: IWDFFile 0xf5060 Fx: 0xf4fe8 [Ref 1]
                State: Created   Parent: 0xf2f80
                No Children
            03: IWDFFile 0xf5100 Fx: 0xf5088 [Ref 101]
                State: Created   Parent: 0xf2f80
                No Children
            04: IWDFFile 0xf51a0 Fx: 0xf5128 [Ref 101]
                State: Created   Parent: 0xf2f80
                No Children
  
  

Additional Information

For more information, see User-Mode Driver Framework Debugging.