buf := NewReader(r)
	allocs := testing.AllocsPerRun(100, func() {
		r.Seek(0, io.SeekStart)
		buf.Reset(r)

		_, err := buf.ReadString('\n')
		if err != nil {
			t.Fatal(err)
		}
	})
	if allocs != 1 {
		t.Errorf("Unexpected number of allocations, got %f, want 1", allocs)
	}
}

		// Expected size cannot be satisfied for
		// requested offset and length
		file.Close()
		return nil, errFileCorrupt
	}

	if offset > 0 {
		if _, err = file.Seek(offset, io.SeekStart); err != nil {
			file.Close()
			return nil, err
		}
	}
	return &sendFileReader{Reader: io.LimitReader(file, length), Closer: file}, nil
}

// CreateFile - creates the file.