WPD_COMMAND_OBJECT_RESOURCES_SEEK_IN_UNITS command
The WPD_COMMAND_OBJECT_RESOURCES_SEEK_IN_UNITS command seeks until a specific offset in the resource data, by using alternate units. Before you call WPD_COMMAND_OBJECT_RESOURCES_SEEK_IN_UNITS, you must open the object resource by calling WPD_COMMAND_OBJECT_RESOURCES_OPEN.
This command changes the seek pointer so that subsequent reads and writes can take place at a different location in the data stream. An error occurs if you start a seek before the beginning of the stream.
Callers may also use this method to obtain the current value of the seek pointer by calling this command with the WPD_PROPERTY_OBJECT_RESOURCES_SEEK_ORIGIN_FLAG parameter set to STREAM_SEEK_CUR and the WPD_PROPERTY_OBJECT_RESOURCES_SEEK_OFFSET parameter set to zero, so that the seek pointer is not changed.
Command category
WPD_CATEGORY_OBJECT_RESOURCES
Parameters
| Parameters |
|---|
The driver expects the following parameters. |
WPD_PROPERTY_OBJECT_RESOURCES_CONTEXT |
WPD_PROPERTY_OBJECT_RESOURCES_SEEK_OFFSET |
WPD_PROPERTY_OBJECT_RESOURCES_STREAM_UNITS |
WPD_PROPERTY_OBJECT_RESOURCES_SEEK_ORIGIN_FLAG |
Return value
| Result |
|---|
The driver should return the following results. |
WPD_PROPERTY_OBJECT_RESOURCES_POSITION_FROM_START |
WPD_PROPERTY_COMMON_HRESULT |
WPD_PROPERTY_COMMON_DRIVER_ERROR_CODE |
Calling methods
Requirements
Header |
PortableDevice.h |
See also