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WdfChildListUpdateChildDescriptionAsMissing function (wdfchildlist.h)

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[Applies to KMDF only]

The WdfChildListUpdateChildDescriptionAsMissing method informs the framework that a specified child device is currently unplugged or otherwise unavailable.

Syntax

NTSTATUS WdfChildListUpdateChildDescriptionAsMissing(
  [in] WDFCHILDLIST                                 ChildList,
  [in] PWDF_CHILD_IDENTIFICATION_DESCRIPTION_HEADER IdentificationDescription
);

Parameters

[in] ChildList

A handle to a child list object.

[in] IdentificationDescription

A pointer to a caller-allocated WDF_CHILD_IDENTIFICATION_DESCRIPTION_HEADER structure that identifies a driver-supplied child identification description.

Return value

WdfChildListUpdateChildDescriptionAsMissing returns STATUS_SUCCESS, or another status value for which NT_SUCCESS(status) equals TRUE, if the operation succeeds. Otherwise, this method might return one of the following values:

Return code Description
STATUS_INVALID_PARAMETER
 An input parameter was invalid.
STATUS_INVALID_DEVICE_REQUEST
 The size of the structure that IdentificationDescription points to was incorrect.
STATUS_NO_SUCH_DEVICE
 The specified device was not found in the child list.
 

This method might also return other NTSTATUS values.

A system bug check occurs if the driver supplies an invalid object handle.

Remarks

Your driver can report that a device is unavailable even if the driver never called WdfChildListAddOrUpdateChildDescriptionAsPresent to report that the device was present. In this case, the WdfChildListUpdateChildDescriptionAsMissing method just returns STATUS_NO_SUCH_DEVICE.

If you want to report that all devices in a child list are unavailable, your driver can simply call WdfChildListBeginScan, followed immediately by WdfChildListEndScan, instead of calling WdfChildListUpdateChildDescriptionAsMissing for each device.

For more information about child devices and child lists, see Dynamic Enumeration.

Examples

The following code example informs the framework that a child device with a specified serial number is unavailable.

PDO_IDENTIFICATION_DESCRIPTION  description;
NTSTATUS  status;

WDF_CHILD_IDENTIFICATION_DESCRIPTION_HEADER_INIT(
                                                 &description.Header,
                                                 sizeof(description)
                                                 );

description.SerialNo = SerialNo;
status = WdfChildListUpdateChildDescriptionAsMissing(
                                                     list,
                                                     &description.Header
                                                     );

Requirements

Requirement Value
Target Platform Universal
Minimum KMDF version 1.0
Header wdfchildlist.h (include Wdf.h)
Library Wdf01000.sys (see Framework Library Versioning.)
IRQL <= DISPATCH_LEVEL
DDI compliance rules DriverCreate(kmdf), KmdfIrql(kmdf), KmdfIrql2(kmdf), KmdfIrqlExplicit(kmdf)

See also

WDF_CHILD_IDENTIFICATION_DESCRIPTION_HEADER

WDF_CHILD_IDENTIFICATION_DESCRIPTION_HEADER_INIT

WdfChildListAddOrUpdateChildDescriptionAsPresent