The FSCTL_QUERY_ALLOCATED_RANGES reply message returns the results of the FSCTL_QUERY_ALLOCATED_RANGES request.This message MUST return an array of zero or more FILE_ALLOCATED_RANGE_BUFFER data elements. The number of FILE_ALLOCATED_RANGE_BUFFER elements returned is computed by dividing the size of the returned output buffer (from SMB, the lower-level protocol that carries the FSCTL) by the size of the FILE_ALLOCATED_RANGE_BUFFER element. Ranges returned are always at least partially within the range specified in the FSCTL_QUERY_ALLOCATED_RANGES request. Zero FILE_ALLOCATED_RANGE_BUFFER data elements MUST be returned when the file has no allocated ranges.Each entry in the output array contains an offset and a length that indicates a range in the file that may contain nonzero data. The actual nonzero data, if any, is somewhere within this range, and the calling application must scan further within the range to locate it and determine if it really is valid data. Multiple instances of valid data may exist within the range.The FILE_ALLOCATED_RANGE_BUFFER data element is as follows.
