_, err := NewReader(bytes.NewReader(b), size)
	if err != ErrFormat {
		t.Errorf("zeroes: error=%v, want %v", err, ErrFormat)
	}

	// repeated directoryEndSignatures
	sig := make([]byte, 4)
	binary.LittleEndian.PutUint32(sig, directoryEndSignature)
	for i := 0; i < size-4; i += 4 {
		copy(b[i:i+4], sig)
	}
	_, err = NewReader(bytes.NewReader(b), size)
	if err != ErrFormat {
		t.Errorf("sigs: error=%v, want %v", err, ErrFormat)

				if len(fieldBuf) < 8 {
					return ErrFormat
				}
				f.UncompressedSize64 = fieldBuf.uint64()
			}
			if needCSize {
				needCSize = false
				if len(fieldBuf) < 8 {
					return ErrFormat
				}
				f.CompressedSize64 = fieldBuf.uint64()
			}
			if needHeaderOffset {
				needHeaderOffset = false
				if len(fieldBuf) < 8 {
					return ErrFormat
				}

pkg archive/zip, type Reader struct, File []*File
pkg archive/zip, type Writer struct
pkg archive/zip, var ErrAlgorithm error
pkg archive/zip, var ErrChecksum error
pkg archive/zip, var ErrFormat error
pkg bufio, func NewReadWriter(*Reader, *Writer) *ReadWriter
pkg bufio, func NewReader(io.Reader) *Reader
pkg bufio, func NewReaderSize(io.Reader, int) *Reader
pkg bufio, func NewWriter(io.Writer) *Writer