WDF_CHILD_RETRIEVE_INFO structure (wdfchildlist.h)

[Applies to KMDF only]

The WDF_CHILD_RETRIEVE_INFO structure contains information about a child device that is obtained by calling WdfChildListRetrieveNextDevice or WdfChildListRetrievePdo.

Syntax

typedef struct _WDF_CHILD_RETRIEVE_INFO {
  ULONG                                                 Size;
  PWDF_CHILD_IDENTIFICATION_DESCRIPTION_HEADER          IdentificationDescription;
  PWDF_CHILD_ADDRESS_DESCRIPTION_HEADER                 AddressDescription;
  WDF_CHILD_LIST_RETRIEVE_DEVICE_STATUS                 Status;
  PFN_WDF_CHILD_LIST_IDENTIFICATION_DESCRIPTION_COMPARE EvtChildListIdentificationDescriptionCompare;
} WDF_CHILD_RETRIEVE_INFO, *PWDF_CHILD_RETRIEVE_INFO;

Members

Size

The size, in bytes, of this structure.

IdentificationDescription

A pointer to a driver-allocated WDF_CHILD_IDENTIFICATION_DESCRIPTION_HEADER structure. The driver must supply a value for this structure's IdentificationDescriptionSize member.

If the driver is calling WdfChildListRetrieveNextDevice and supplying an EvtChildListIdentificationDescriptionCompare callback function, the driver must also provide an identification description that the callback function can use to compare with an entry in a child list.

If the driver is calling WdfChildListRetrievePdo, the driver must fill in the entire identification description.

AddressDescription

A pointer to a driver-allocated WDF_CHILD_ADDRESS_DESCRIPTION_HEADER structure. The driver must supply a value for this structure's AddressDescriptionSize member. The framework fills in the rest of the address description when it retrieves a child from the child list. If the value of AddressDescriptionSize is NULL, address description information is not retrieved.

Status

A WDF_CHILD_LIST_RETRIEVE_DEVICE_STATUS-typed value that the framework provides.

EvtChildListIdentificationDescriptionCompare

A driver-supplied pointer to an EvtChildListIdentificationDescriptionCompare callback function.

If the driver is calling WdfChildListRetrieveNextDevice, this pointer is optional and can be NULL.

If the driver is calling WdfChildListRetrievePdo, this pointer is not used.

Remarks

The WDF_CHILD_RETRIEVE_INFO structure is passed to the WdfChildListRetrieveNextDevice and WdfChildListRetrievePdo methods.

To initialize a WDF_CHILD_RETRIEVE_INFO structure, the driver must call WDF_CHILD_RETRIEVE_INFO_INIT.

Requirements

See also

EvtChildListIdentificationDescriptionCompare

WDF_CHILD_ADDRESS_DESCRIPTION_HEADER

WDF_CHILD_IDENTIFICATION_DESCRIPTION_HEADER

WDF_CHILD_LIST_RETRIEVE_DEVICE_STATUS

WdfChildListRetrieveNextDevice

WdfChildListRetrievePdo