WDF_IO_TARGET_OPEN_PARAMS_INIT_OPEN_BY_FILE function (wdfiotarget.h)
[Applies to UMDF only]
The WDF_IO_TARGET_OPEN_PARAMS_INIT_OPEN_BY_FILE function initializes a driver's WDF_IO_TARGET_OPEN_PARAMS structure so the driver can open an I/O target by specifying a filename.
Syntax
void WDF_IO_TARGET_OPEN_PARAMS_INIT_OPEN_BY_FILE(
[out] PWDF_IO_TARGET_OPEN_PARAMS Params,
[in, optional] PCUNICODE_STRING FileName
);
Parameters
[out] Params
A pointer to a driver-allocated WDF_IO_TARGET_OPEN_PARAMS structure, which the function initializes.
[in, optional] FileName
A value for the FileName member of the WDF_IO_TARGET_OPEN_PARAMS structure. Most drivers specify NULL here unless the lower target supports Device Namespace Access.
Return value
None
Remarks
The WDF_IO_TARGET_OPEN_PARAMS_INIT_OPEN_BY_FILE function zeros the specified WDF_IO_TARGET_OPEN_PARAMS structure and sets its Size member. It also sets the structure's Type member to WdfIoTargetOpenLocalTargetByFile and sets the FileName member if the driver supplies a filename.
A driver can explicitly close the I/O target by calling WdfIoTargetClose. If the driver does not explicitly close the target, the framework closes the target automatically when the device is removed (an I/O target is by default parented to the device).
Examples
The following code example shows how a UMDF driver can open a local target with a file object as described in WDF_IO_TARGET_OPEN_TYPE:
WDF_OBJECT_ATTRIBUTES ioTargetAttrib;
WDFIOTARGET ioTarget;
WDF_IO_TARGET_OPEN_PARAMS openParams;
//
// Create target
//
WDF_OBJECT_ATTRIBUTES_INIT_CONTEXT_TYPE(&ioTargetAttrib, TARGET_DEVICE_INFO);
status = WdfIoTargetCreate(device, &ioTargetAttrib, &ioTarget);
if (!NT_SUCCESS(status)) {
return status;
}
//
// Open target
//
WDF_IO_TARGET_OPEN_PARAMS_INIT_OPEN_BY_FILE(&openParams, NULL);
status = WdfIoTargetOpen(ioTarget, &openParams);
if (!NT_SUCCESS(status)) {
WdfObjectDelete(ioTarget);
return status;
}
//
// create a request
//
//
// Format the request for the above target
//
//
// Send request to above target
//
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows 8.1 |
| Target Platform | Universal |
| Minimum UMDF version | 2.0 |
| Header | wdfiotarget.h (include Wdf.h) |
| IRQL | Any level |