subset method
Implementation
List<int> subset(int start, [int? end]) {
if (_bufferPosition > 0) {
flush();
}
final pos = _fileHandle.position;
if (start < 0) {
start = pos + start;
}
var length = 0;
if (end == null) {
end = pos;
} else if (end < 0) {
end = pos + end;
}
length = (end - start);
_fileHandle.position = start;
final buffer = Uint8List(length);
_fileHandle.readInto(buffer);
_fileHandle.position = pos;
return buffer;
}