!ks.objhdr

The !ks.objhdr extension displays the kernel streaming object header associated with the specified file object.

Syntax

!ks.objhdr FileObject [Level] [Flags]  

Parameters

FileObject

This parameter specifies a pointer to a WDM file object. If FileObject is not valid, the command returns an error.

Level

Optional. Values are the same as those for !ks.dump.

Flags

Optional. Values are the same as those for !ks.dump.

DLL

Comments

Levels and flags for !ks.objhdr are identical to those described in !ks.dump.

The output from !ks.allstreams and !ks.enumdevobj can be used as the input for !ks.objhdr. To do this with the avssamp sample, for instance, issue the following commands:

kd> !ks.allstreams
6 Kernel Streaming FDOs found:
    Functional Device 8299be18 [\Driver\smwdm]
    Functional Device 827c86d8 [\Driver\wdmaud]
    Functional Device 827c0f08 [\Driver\sysaudio]
    Functional Device 82424590 [\Driver\avssamp]
    Functional Device 82423720 [\Driver\MSPQM]
    Functional Device 82b91a88 [\Driver\MSPCLOCK]
kd> !ks.enumdevobj 82424590
WDM device object 82424590:
    Corresponding KSDEVICE        82427540
    Factory 8285baa4 [Descriptor f7a333c8] instances:
        82837a34 
kd> !ks.objhdr 82837a34 7

The results of this command might be lengthy. Issue a Ctrl-BREAK (WinDbg) or Ctrl-C (NTSD, CDB, KD) to stop the output.

Here's a separate example:

kd> !ks.objhdr 81D828B8 7
Adjusting file object 81D828B8 to object header 81BC1008

Object Header 81BC1008
    Associated Create Items:
        Create Item F9F77E98
            CreateFunction = ks!CKsFilter::DispatchCreatePin+0x00
            ObjectClass = {146F1A80-4791-11D0-A5D6-28DB04C10000}
            Flags = 0
    Child Create Handler List:
        Create Item F9F85AA0
            CreateFunction = ks!CKsPin::DispatchCreateAllocator+0x00
            ObjectClass = {642F5D00-4791-11D0-A5D6-28DB04C10000}
            Flags = 0
        Create Item F9F85AB8
            CreateFunction = ks!CKsPin::DispatchCreateClock+0x00
            ObjectClass = {53172480-4791-11D0-A5D6-28DB04C10000}
            Flags = 0
        Create Item F9F85AD0
            CreateFunction = ks!CKsPin::DispatchCreateNode+0x00
            ObjectClass = {0621061A-EE75-11D0-B915-00A0C9223196}
            Flags = 0
    DispatchTable:
        Dispatch Table F9F85AE8
            DeviceIoControl = ks!CKsPin::DispatchDeviceIoControl+0x00
            Read = ks!KsDispatchInvalidDeviceRequest+0x00
            Write = ks!KsDispatchInvalidDeviceRequest+0x00
            Flush = ks!KsDispatchInvalidDeviceRequest+0x00
            Close = ks!CKsPin::DispatchClose+0x00
            QuerySecurity = ks!KsDispatchQuerySecurity+0x00
            SetSecurity = ks!KsDispatchSetSecurity+0x00
            FastDeviceIoControl = ks!KsDispatchFastIoDeviceControlFailure+0x00
            FastRead = ks!KsDispatchFastReadFailure+0x00
            FastWrite = ks!KsDispatchFastReadFailure+0x00
    TargetState: KSTARGET_STATE_ENABLED
    TargetDevice: 00000000
    BaseDevice  : 81BBDF10
    Stack Depth : 1
    Corresponding AVStream object = 81A971B0

Additional Information

For more information, see Kernel Streaming Debugging.