OutputBuffer is of type FILE_POSITION_INFORMATION, as specified in [MS-FSCC] section 2.4.32.
Pseudocode for the operation is as follows:
If OutputBufferSize is less than the size, in bytes, of the FILE_POSITION_INFORMATION structure, the operation MUST be failed with STATUS_INFO_LENGTH_MISMATCH.
The objects store MUST set OutputBuffer.CurrentByteOffset equal to Open.CurrentByteOffset.
The operation returns STATUS_SUCCESS.<115>