var gnuLongName, gnuLongLink string

	// Externally, Next iterates through the tar archive as if it is a series of
	// files. Internally, the tar format often uses fake "files" to add meta
	// data that describes the next file. These meta data "files" should not
	// normally be visible to the outside. As such, this loop iterates through
	// one or more "header files" until it finds a "normal file".
	format := FormatUSTAR | FormatPAX | FormatGNU

	exitRe := regexp.MustCompile(exitReStr.String())

	return &exitCodeFilter{w: w, exitRe: exitRe}, exitStr
}

func (f *exitCodeFilter) Write(data []byte) (int, error) {
	n := len(data)
	f.buf.Write(data)
	// Flush to w until a potential match of exitRe
	b := f.buf.Bytes()
	match := f.exitRe.FindIndex(b)
	if match == nil {
		// Flush all of the buffer.
		_, err := f.w.Write(b)

		if err != nil {
			t.Fatal(err)
		}

		data, err := io.ReadAll(tr)
		if err != nil {
			t.Fatal(err)
		}

		if hdr.Name != curfname {
			t.Fatalf("got filename %v, want %v",
				curfname, hdr.Name)
		}

		origdata := fsys[curfname].Data
		if string(data) != string(origdata) {
			t.Fatalf("got file content %v, want %v",
				data, origdata)
		}
	}
}

	}

	n := lengths[len(lengths)-1]
	a := make([]byte, n+1)
	b := make([]byte, n+1)
	for _, len := range lengths {
		// randomish but deterministic data. No 0 or 255.
		for i := 0; i < len; i++ {
			a[i] = byte(1 + 31*i%254)
			b[i] = byte(1 + 31*i%254)
		}
		// data past the end is different
		for i := len; i <= n; i++ {
			a[i] = 8
			b[i] = 9
		}
		cmp := Compare(a[:len], b[:len])
		if cmp != 0 {

		t.Errorf("Header mismatch.\n got %+v\nwant %+v", rHdr, hdr)
	}
	rData, err := io.ReadAll(tr)
	if err != nil {
		t.Fatalf("Read: %v", err)
	}
	if !bytes.Equal(rData, data) {
		t.Errorf("Data mismatch.\n got %q\nwant %q", rData, data)
	}
}

type headerRoundTripTest struct {
	h  *Header
	fm fs.FileMode
}

func TestHeaderRoundTrip(t *testing.T) {
	vectors := []headerRoundTripTest{{

		return fmt.Errorf("ideviceimagemounter: %v", err)
	}
	var info struct {
		Dict struct {
			Data []byte `xml:",innerxml"`
		} `xml:"dict"`
	}
	if err := xml.Unmarshal(out, &info); err != nil {
		return fmt.Errorf("mountDevImage: failed to decode mount information: %v", err)
	}
	dict, err := parsePlistDict(info.Dict.Data)
	if err != nil {
		return fmt.Errorf("mountDevImage: failed to parse mount information: %v", err)
	}

	type _C___mpz_struct struct {
		_mp_alloc _C_int;
		_mp_size _C_int;
		_mp_d *_C_mp_limb_t;
	}
	type _C_mpz_t [1]_C___mpz_struct

and then replaces each occurrence of a type C.xxx with _C_xxx.

If xxx is data, cgo arranges for C.xxx to refer to the C variable,
with the type translated as described above.  To do this, cgo must
introduce a Go variable that points at the C variable (the linker can