if err != nil {
		return err
	}
	ino := fi.Sys().(*syscall.Stat_t).Ino

	mu.Lock()
	if i, dup := inodes[f]; dup && i != ino {
		mu.Unlock()
		return &fs.PathError{
			Op:   lt.String(),
			Path: f.Name(),
			Err:  errors.New("inode for file changed since last Lock or RLock"),
		}
	}
	inodes[f] = ino

	var wait chan File
	l := locks[ino]
	if l.owner == f {

func (fs *fileStat) ModTime() time.Time { return fs.modTime }
func (fs *fileStat) Sys() any           { return &fs.sys }

func sameFile(fs1, fs2 *fileStat) bool {
	return fs1.sys.Dev == fs2.sys.Dev && fs1.sys.Ino == fs2.sys.Ino

// https://github.com/WebAssembly/WASI/blob/main/legacy/preview1/docs.md#-dirent-record
const sizeOfDirent = 24

func direntIno(buf []byte) (uint64, bool) {
	return readInt(buf, unsafe.Offsetof(syscall.Dirent{}.Ino), unsafe.Sizeof(syscall.Dirent{}.Ino))
}

func direntReclen(buf []byte) (uint64, bool) {
	namelen, ok := direntNamlen(buf)
	return sizeOfDirent + namelen, ok
}

func direntNamlen(buf []byte) (uint64, bool) {

		if !ok || reclen > uint64(len(buf)) {
			return origlen, count, names
		}
		rec := buf[:reclen]
		buf = buf[reclen:]
		ino, ok := direntIno(rec)
		if !ok {
			break
		}
		// See src/os/dir_unix.go for the reason why this condition is
		// excluded on wasip1.
		if ino == 0 && runtime.GOOS != "wasip1" { // File absent in directory.
			continue
		}
		const namoff = uint64(unsafe.Offsetof(Dirent{}.Name))

	Fsid    uint64
	Namelen uint64
	Frsize  uint64
	Flags   uint64
	_       [4]uint64
}

type direntLE struct {
	Reclen uint16
	Namlen uint16
	Ino    uint32
	Extra  uintptr
	Name   [256]byte
}

type Dirent struct {
	Ino    uint64
	Off    int64
	Reclen uint16
	Type   uint8
	Name   [256]uint8
	_      [5]byte
}

type FdSet struct {
	Bits [64]int32
}

		reclen, ok := direntReclen(buf)
		if !ok || reclen > uint64(len(buf)) {
			return origlen, count, names
		}
		rec := buf[:reclen]
		buf = buf[reclen:]
		ino, ok := direntIno(rec)
		if !ok {
			break
		}
		if ino == 0 { // File absent in directory.
			continue
		}
		const namoff = uint64(unsafe.Offsetof(Dirent{}.Name))
		namlen, ok := direntNamlen(rec)
		if !ok || namoff+namlen > uint64(len(rec)) {

		if s.Dev != topLevelStat.Dev {
			// don't descend into directories on other devices
			return filepath.SkipDir
		}

		// Dedupe hardlinks
		if s.Nlink > 1 {
			if _, ok := dedupedInodes[s.Ino]; !ok {
				dedupedInodes[s.Ino] = struct{}{}
			} else {
				return nil
			}
		}

		if consumption == nil {
			usage.Bytes += int64(s.Blocks) * int64(512) // blocksize in bytes
		}

		if inodes == nil {

}

func Stat(path string, s *Stat_t) (err error) {
	st := &stat_t{}
	err = stat(path, st)
	fillStat_t(s, st)
	return
}

func fillStat_t(s *Stat_t, st *stat_t) {
	s.Dev = st.Dev
	s.Ino = st.Ino
	s.Mode = st.Mode
	s.Nlink = st.Nlink
	s.Uid = st.Uid
	s.Gid = st.Gid
	s.Rdev = st.Rdev
	s.Size = st.Size
	s.Atim = Timespec{int64(st.Atime), int64(st.Atime_nsec)}

	S_ISUID  = 0x800
	S_ISGID  = 0x400
	S_ISVTX  = 0x200
	S_IRUSR  = 0x100
	S_IWUSR  = 0x80
	S_IXUSR  = 0x40
	S_IRWXG  = 0x38
	S_IRWXO  = 0x7
)

type Stat_t struct {
	Dev       uint64
	Ino       uint64
	Mode      uint32
	Nlink     uint32
	Uid       uint32
	Gid       uint32
	Rdev      uint64
	Size      int64
	Atim      Timespec
	Mtim      Timespec
	Ctim      Timespec
	Blksize   int32

	Msgrcv   int64
	Nsignals int64
	Nvcsw    int64
	Nivcsw   int64
}

type Rlimit struct {
	Cur uint64
	Max uint64
}

type _Gid_t uint32

type Stat_t struct {
	Dev               uint64
	Ino               uint64
	Mode              uint32
	Nlink             uint32
	Uid               uint32
	Gid               uint32
	Rdev              uint64
	X__pad1           uint64
	Size              int64