}

var (
	mu     sync.Mutex
	inodes = map[File]inode{}
	locks  = map[inode]inodeLock{}
)

func lock(f File, lt lockType) (err error) {
	// POSIX locks apply per inode and process, and the lock for an inode is
	// released when *any* descriptor for that inode is closed. So we need to
	// synchronize access to each inode internally, and must serialize lock and
	// unlock calls that refer to the same inode through different descriptors.

		}
		next()          // dev
		inode := next() // inode
		if line == nil {
			continue
		}
		file := string(line)

		// Trim deleted file marker.
		deletedStr := " (deleted)"
		deletedLen := len(deletedStr)
		if len(file) >= deletedLen && file[len(file)-deletedLen:] == deletedStr {
			file = file[:len(file)-deletedLen]
		}

		if len(inode) == 1 && inode[0] == '0' && file == "" {

			if errno == syscall.EINTR {
				continue
			}
			return names, dirents, infos, &PathError{Op: "readdir", Path: f.name, Err: errno}
		}
		if entptr == nil { // EOF
			break
		}
		// Darwin may return a zero inode when a directory entry has been
		// deleted but not yet removed from the directory. The man page for
		// getdirentries(2) states that programs are responsible for skipping
		// those entries:
		//

	f2 := mustOpen(t, f.Name())
	defer f2.Close()

	doUnlockTF := false
	switch runtime.GOOS {
	case "aix", "solaris":
		// When using POSIX locks (as on Solaris), we can't safely read-lock the
		// same inode through two different descriptors at the same time: when the
		// first descriptor is closed, the second descriptor would still be open but
		// silently unlocked. So a second RLock must block instead of proceeding.

func (fs *fileStat) IsDir() bool  { return fs.Mode().IsDir() }

// SameFile reports whether fi1 and fi2 describe the same file.
// For example, on Unix this means that the device and inode fields
// of the two underlying structures are identical; on other systems
// the decision may be based on the path names.
// SameFile only applies to results returned by this package's [Stat].
// It returns false in other cases.

	ENOTSUP         Errno = EOPNOTSUPP /* Not supported */
	ENOMEDIUM       Errno = 123        /* No medium (in tape drive) */
	ECANCELED       Errno = 125        /* Operation canceled. */
	ELBIN           Errno = 2048       /* Inode is remote (not really error) */
	EFTYPE          Errno = 2049       /* Inappropriate file type or format */
	ENMFILE         Errno = 2050       /* No more files */
	EPROCLIM        Errno = 2051

}

type CryptoReportKPP struct {
	Type [64]int8
}

type CryptoReportAcomp struct {
	Type [64]int8
}

type LoopInfo struct {
	Number           int32
	Device           uint16
	Inode            uint64
	Rdevice          uint16
	Offset           int32
	Encrypt_type     int32
	Encrypt_key_size int32
	Flags            int32
	Name             [64]int8
	Encrypt_key      [32]uint8

}

type CryptoReportKPP struct {
	Type [64]int8
}

type CryptoReportAcomp struct {
	Type [64]int8
}

type LoopInfo struct {
	Number           int32
	Device           uint32
	Inode            uint64
	Rdevice          uint32
	Offset           int32
	Encrypt_type     int32
	Encrypt_key_size int32
	Flags            int32
	Name             [64]int8
	Encrypt_key      [32]uint8

}

type CryptoReportKPP struct {
	Type [64]int8
}

type CryptoReportAcomp struct {
	Type [64]int8
}

type LoopInfo struct {
	Number           int32
	Device           uint64
	Inode            uint64
	Rdevice          uint64
	Offset           int32
	Encrypt_type     int32
	Encrypt_key_size int32
	Flags            int32
	Name             [64]int8
	Encrypt_key      [32]uint8

}

type CryptoReportKPP struct {
	Type [64]int8
}

type CryptoReportAcomp struct {
	Type [64]int8
}

type LoopInfo struct {
	Number           int32
	Device           uint32
	Inode            uint64
	Rdevice          uint32
	Offset           int32
	Encrypt_type     int32
	Encrypt_key_size int32
	Flags            int32
	Name             [64]int8
	Encrypt_key      [32]uint8