readFromFileAtMax method
Reads a block of data of the given length from a specific position.
Returns a Readbuffer containing the read data.
Implementation
@override
Future<Readbuffer> readFromFileAtMax(int indexBlockPosition, int indexBlockSize) {
Uint8List c = content.sublist(indexBlockPosition, indexBlockPosition + indexBlockSize);
return Future.value(Readbuffer(c, indexBlockPosition));
}