// The only required bit is [ModeDir] for directories.
type FileMode = fs.FileMode

// The defined file mode bits are the most significant bits of the [FileMode].
// The nine least-significant bits are the standard Unix rwxrwxrwx permissions.
// The values of these bits should be considered part of the public API and
// may be used in wire protocols or disk representations: they must not be
// changed, although new bits might be added.
const (

// The only required bit is [ModeDir] for directories.
type FileMode uint32

// The defined file mode bits are the most significant bits of the [FileMode].
// The nine least-significant bits are the standard Unix rwxrwxrwx permissions.
// The values of these bits should be considered part of the public API and
// may be used in wire protocols or disk representations: they must not be
// changed, although new bits might be added.
const (

Remote system type is UNIX.
Using binary mode to transfer files.
ftp> ls runner/
229 Entering Extended Passive Mode (|||39155|)
150 Opening ASCII mode data connection for file list
drwxrwxrwx 1 nobody nobody            0 Jan  1 00:00 chunkdocs/
drwxrwxrwx 1 nobody nobody            0 Jan  1 00:00 testdir/
...
```

Following example shows how to list an object and download it locally via `ftp` client:

```

        assertInvalidUnixPermission("r|xrwxrwx", "'r|xrwxrwx' isn't a proper Unix permission. '|' is not a valid Unix permission WRITE flag, must be 'w' or '-'.");
        assertInvalidUnixPermission("rwxr|xrwx", "'rwxr|xrwx' isn't a proper Unix permission. '|' is not a valid Unix permission WRITE flag, must be 'w' or '-'.");

	fs.WalkDir(m, ".", func(path string, d fs.DirEntry, err error) error {
		fi, err := d.Info()
		if err != nil {
			return err
		}
		fmt.Fprintf(buf, "%s: %v\n", path, fi.Mode())
		return nil
	})
	want := `
.: drwxrwxrwx
a: dr-xr-xr-x
a/b.txt: -rw-rw-rw-
`[1:]
	got := buf.String()
	if want != got {
		t.Errorf("MapFS modes want:\n%s\ngot:\n%s\n", want, got)
	}
}

func TestMapFSFileInfoName(t *testing.T) {
	m := MapFS{