// if modification time is the only timestamp being encoded.
		var mbuf [9]byte // 2*SizeOf(uint16) + SizeOf(uint8) + SizeOf(uint32)
		mt := uint32(fh.Modified.Unix())
		eb := writeBuf(mbuf[:])
		eb.uint16(extTimeExtraID)
		eb.uint16(5)  // Size: SizeOf(uint8) + SizeOf(uint32)
		eb.uint8(1)   // Flags: ModTime
		eb.uint32(mt) // ModTime
		fh.Extra = append(fh.Extra, mbuf[:]...)
	}

//     pthread_mutex_lock(&mu);
//     done = all_done;
//     pthread_mutex_unlock(&mu);
//   }
//   return NULL;
// }
//
// void trial(int argc) {
//   int i;
//   nts = argc;
//   t = calloc(nts, sizeof(pthread_t));
//   pthread_mutex_init(&mu, NULL);
//   for (i = 0; i < nts; i++) {
//     pthread_create(&t[i], NULL, aFn, NULL);
//   }
// }
//
// void cleanup(void) {
//   int i;
//   pthread_mutex_lock(&mu);

struct_, union_, or enum_, as in C.struct_stat.

The size of any C type T is available as C.sizeof_T, as in
C.sizeof_struct_stat.

A C function may be declared in the Go file with a parameter type of
the special name _GoString_. This function may be called with an
ordinary Go string value. The string length, and a pointer to the
string contents, may be accessed by calling the C functions

	size_t _GoStringLen(_GoString_ s);

	// the compiler is going to pad it by one (see issue 9401).
	// We can't permit that, because then the size of the Go
	// struct will not be the same as the size of the C struct.
	// Our only option in such a case is to remove the field,
	// which means that it cannot be referenced from Go.
	for off > 0 && sizes[len(sizes)-1] == 0 {
		n := len(sizes)
		fld = fld[0 : n-1]
		sizes = sizes[0 : n-1]

func NewReader(r io.ReaderAt, size int64) (*Reader, error) {
	if size < 0 {
		return nil, errors.New("zip: size cannot be negative")
	}
	zr := new(Reader)
	var err error
	if err = zr.init(r, size); err != nil && err != ErrInsecurePath {
		return nil, err
	}
	return zr, err
}

func (r *Reader) init(rdr io.ReaderAt, size int64) error {
	end, baseOffset, err := readDirectoryEnd(rdr, size)

}

func TestEqualExhaustive(t *testing.T) {
	var size = 128
	if testing.Short() {
		size = 32
	}
	a := make([]byte, size)
	b := make([]byte, size)
	b_init := make([]byte, size)
	// randomish but deterministic data
	for i := 0; i < size; i++ {
		a[i] = byte(17 * i)
		b_init[i] = byte(23*i + 100)
	}

	for len := 0; len <= size; len++ {
		for x := 0; x <= size-len; x++ {
			for y := 0; y <= size-len; y++ {

const (
	magicGNU, versionGNU     = "ustar ", " \x00"
	magicUSTAR, versionUSTAR = "ustar\x00", "00"
	trailerSTAR              = "tar\x00"
)

// Size constants from various tar specifications.
const (
	blockSize  = 512 // Size of each block in a tar stream
	nameSize   = 100 // Max length of the name field in USTAR format
	prefixSize = 155 // Max length of the prefix field in USTAR format

	directoryEndLen          = 22         // + comment
	dataDescriptorLen        = 16         // four uint32: descriptor signature, crc32, compressed size, size
	dataDescriptor64Len      = 24         // two uint32: signature, crc32 | two uint64: compressed size, size
	directory64LocLen        = 20         //
	directory64EndLen        = 56         // + extra

	// Constants for the first byte in CreatorVersion.
	creatorFAT    = 0

)

const (
	// MaxScanTokenSize is the maximum size used to buffer a token
	// unless the user provides an explicit buffer with [Scanner.Buffer].
	// The actual maximum token size may be smaller as the buffer
	// may need to include, for instance, a newline.
	MaxScanTokenSize = 64 * 1024

	startBufSize = 4096 // Size of initial allocation for buffer.
)

	// into the file, so we can't warn here.
	//
	// The most common case is union types, which begin with
	// _Ctype_union and for which typedef[name] is a Go byte
	// array of the appropriate size (such as [4]byte).
	// Substitute those union types with byte arrays.
	for name, id := range goIdent {
		if id.Name == name && strings.Contains(name, "_Ctype_union") {
			if def := typedef[name]; def != nil {