RawFileSystem does not support chown/chmod? about go-fuse HOT 5 CLOSED

package main

import (
        "context"
        "flag"
        "fmt"
        "github.com/hanwen/go-fuse/v2/fs"
        "github.com/hanwen/go-fuse/v2/fuse"
        "log"
        "syscall"
)

type HelloRoot struct {
        fs.Inode
}

func (r *HelloRoot) OnAdd(ctx context.Context) {
        ch := r.NewPersistentInode(
                ctx, &fs.MemRegularFile{
                        Data: []byte("file.txt"),
                        Attr: fuse.Attr{
                                Mode: 0644,
                        },
                }, fs.StableAttr{Ino: 2})
        r.AddChild("file.txt", ch, false)
}

func (r *HelloRoot) Getattr(ctx context.Context, fh fs.FileHandle, out *fuse.AttrOut) syscall.Errno {
        out.Mode = 0755
        fmt.Printf(".....lllllll------\n")
        return 0
}

func (r *HelloRoot) SetAttr(cancel <-chan struct{}, in *fuse.SetAttrIn, out *fuse.AttrOut) fuse.Status {
        out.Mode = 777
        fmt.Printf("...asdfasdfasdfasd....\n")
        return 0
}

var _ = (fs.NodeGetattrer)((*HelloRoot)(nil))
var _ = (fs.NodeOnAdder)((*HelloRoot)(nil))

func main() {
        flag.Parse()
        if len(flag.Args()) < 1 {
                log.Fatal("Usage:\n  hello MOUNTPOINT")
        }
        opts := &fs.Options{}
        opts.Debug = true
        server, err := fs.Mount(flag.Arg(0), &HelloRoot{}, opts)
        if err != nil {
                log.Fatalf("Mount fail: %v\n", err)
        }
        server.Wait()
}

--- 1st terminal ---

$ cd go-fuse/example/loopback

$ go build

$ mkdir a b

$ sudo ./loopback b a
Mounted!

--- 2nd terminal -----

$ sudo -s

# cd go-fuse/example/loopback/b

# touch test.txt

# ls -l
total 0
-rw-r--r--. 1 root root 0 18. Jan 08:15 test.txt

# chown jakob test.txt

# ls -l
total 0
-rw-r--r--. 1 jakob root 0 18. Jan 08:15 test.txt