return
	}
	wdSet = true
	wdStr = wd
	return wd, nil
}

func Chdir(path string) error {
	// If Chdir is to a relative path, sync working dir first
	if fixwd(path) {
		defer runtime.UnlockOSThread()
	}
	wdmu.Lock()
	defer wdmu.Unlock()

	runtime.LockOSThread()
	defer runtime.UnlockOSThread()
	if err := chdir(path); err != nil {
		return err
	}

	wd, err := getwd()
	if err != nil {

stdout '\(cached\)'

# Files should be tracked even if the test changes its working directory.
go test testcache -run=Chdir
go test testcache -run=Chdir
stdout '\(cached\)'
cp 6x.txt testcache/file.txt
go test testcache -run=Chdir
! stdout '\(cached\)'
go test testcache -run=Chdir
stdout '\(cached\)'

# The content of files should affect caching, provided that the mtime also changes.

				println("unshare not permitted")
				os.Exit(0)
			}
			println("failed to unshare fs:", err.Error())
			os.Exit(1)
		}
		// Chdir to somewhere else on this thread.
		// On systems other than Linux, this is a no-op.
		if err := chdir(os.TempDir()); err != nil {
			println("failed to chdir:", err.Error())
			os.Exit(1)
		}

		// The state on this thread is now considered "tainted", but it

			for fileName, fileContent := range tt.files {
				err := os.WriteFile(path.Join(tmp, fileName), []byte(fileContent), 0666)
				require.NoError(t, err, "create input file")
			}
			defer os.Chdir(cwd)
			require.NoError(t, os.Chdir(tmp), "change into tmp directory")
			in := strings.NewReader(tt.in)
			var out bytes.Buffer
			err := generate(in, &out, tt.data)
			if tt.expectedErr == "" {
				require.NoError(t, err, "expand template")

}

func unshareFs() error {
	err := syscall.Unshare(syscall.CLONE_FS)
	if testenv.SyscallIsNotSupported(err) {
		return errNotPermitted
	}
	return err
}

func chdir(path string) error {
	return syscall.Chdir(path)

	}
	return nil
}

// Chdir changes the current working directory to the file,
// which must be a directory.
// If there is an error, it will be of type [*PathError].
func (f *File) Chdir() error {
	if err := f.checkValid("chdir"); err != nil {
		return err
	}
	if e := f.pfd.Fchdir(); e != nil {
		return f.wrapErr("chdir", e)
	}
	return nil
}

}

func tidExists(tid int) (exists, supported bool, err error) {
	return false, false, nil
}

func getcwd() (string, error) {
	return "", nil
}

func unshareFs() error {
	return nil
}

func chdir(path string) error {
	return nil

		// every time fixLongPath is called with a relative path, so we use a cache.
		// Note that getwdCache might be outdated if the working directory has been
		// changed without using os.Chdir, i.e. using syscall.Chdir directly or cgo.
		// This is fine, as the worst that can happen is that we fail to fix the path.
		getwdCache.Lock()
		if getwdCache.dir == "" {
			// Init the working directory cache.

	// If there is no SysProcAttr (ie. no Chroot or changed
	// UID/GID), double-check existence of the directory we want
	// to chdir into. We can make the error clearer this way.
	if attr != nil && attr.Sys == nil && attr.Dir != "" {
		if _, err := Stat(attr.Dir); err != nil {
			pe := err.(*PathError)
			pe.Op = "chdir"
			return nil, pe
		}
	}

	sysattr := &syscall.ProcAttr{
		Dir: attr.Dir,
		Env: attr.Env,

	l.add("getenv", key)
}

func (l *testLog) Open(name string) {
	l.add("open", name)
}

func (l *testLog) Stat(name string) {
	l.add("stat", name)
}

func (l *testLog) Chdir(name string) {
	l.add("chdir", name)
}

// add adds the (op, name) pair to the test log.
func (l *testLog) add(op, name string) {
	if strings.Contains(name, "\n") || name == "" {
		return
	}

	l.mu.Lock()