Your application sets this access level by calling the IPortableDeviceValues::SetUnsignedIntegerValue method on the command parameters that it passes to the SendCommand method. Some custom commands may require a specific Input/Output Control Code (IOCTL) access level. You also must call SendCommand to send any custom driver commands driver. WPD_COMMAND_STILL_IMAGE_CAPTURE_INITIATE.WPD_COMMAND_DEVICE_HINTS_GET_CONTENT_LOCATION.The following commands have no corresponding method: The only way to call these commands is by using SendCommand. Some commands have no corresponding Windows Portable Devices methods. Most Windows Portable Devices methods actually work by sending one or more of the Windows Portable Devices commands for you and wrapping the parameters for you. A list of commands defined by Windows Portable Devices, with the required parameters and return values, is given in Commands. Each command has a list of required and optional parameters and results that must be packaged with the command for the driver to perform the requested action. A command is a PROPERTYKEY that is sent to the driver to indicate the expected action, along with a list of required parameters. This function is used to send a command directly to the driver. This does not indicate that the command itself succeeded-you must check ppResults to determine the success or failure of the command.Īt least one of the arguments was a NULL pointer. The command was successfully received by the driver. The possible HRESULT values returned by this method include, but are not limited to, those in the following table. (For more information, see Remarks.) These errors are returned in the HRESULT values of the ppResults parameter. The returned value indicates success or failure to send a command and return a result from the driver it does not indicate whether the driver supports the command or if it encountered some error in processing the command. The retrieved values vary by command see the appropriate command documentation in Commands to learn what values are returned by each command call. The caller must release this interface when it is done with it. For example, to reset a device, you would send WPD_COMMAND_COMMON_RESET_DEVICE.pid.Īddress of a variable that receives a pointer to an IPortableDeviceValues interface that indicates the results of the command results, including success or failure, and any command values returned by the device. For example, to reset a device, you would send WPD_COMMAND_COMMON_RESET_DEVICE.fmtid. The category GUID of the command to send. For a list of the parameters that are required for each command, see Commands. Additional parameters vary depending on the command. This interface must include the following two values to indicate the command. Pointer to an IPortableDeviceValues interface that specifies the command and parameters to call on the device. The SendCommand method sends a command to the device and retrieves the results synchronously.
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