IWiaItem2::DeviceCommand method
Issues a command to a Windows Image Acquisition (WIA) 2.0 hardware device.
Syntax
HRESULT DeviceCommand(
[in] LONG lFlags,
[in] const GUID *pCmdGUID,
[in, out] IWiaItem2 **ppIWiaItem2
);
Parameters
-
lFlags [in]
-
Type: LONG
Currently unused. Should be set to zero.
-
pCmdGUID [in]
-
Type: const GUID*
Specifies the command to send to the WIA 2.0 device. See WIA Device Commands.
-
ppIWiaItem2 [in, out]
-
Type: IWiaItem2**
Receives the address of a pointer to the IWiaItem2 item created by the command, if any.
Return value
Type: HRESULT
In addition to the standard COM error codes, the method may return the following value.
| Return code | Description |
|---|---|
|
The command is not implemented for the IWiaItem2 interface on which the method is called. The numeric value for this error is not yet defined. |
Remarks
The behavior of this method is different depending on the category of the node on which the method is called.
When the application sends the WIA_CMD_TAKE_PICTURE command to the device using the IWiaItem2::DeviceCommand method, the WIA 2.0 run-time system creates an IWiaItem2 object to represent the image. The IWiaItem2::DeviceCommand method stores the address of the interface in the ppIWiaItem2 parameter.
Applications must call the IUnknown::Release method on the interface pointers they receive through the ppIWiaItem2 parameter.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client |
Windows Vista [desktop apps only] |
| Minimum supported server |
Windows Server 2008 [desktop apps only] |
| Header |
|
| IDL |
|