presto-orc/src/main/java/io/prestosql/orc/FileOrcDataSource.java/FileOrcDataSource/readInternal
class FileOrcDataSource:    @Override
    protected void readInternal(long position, byte[] buffer, int bufferOffset, int bufferLength)
            throws IOException
    {
        input.seek(position);
        input.readFully(buffer, bufferOffset, bufferLength);
    }