Miklos Szeredi <miklos@xxxxxxxxxx> wrote: > That presumably means the mount ID <-> mount path mapping already > exists, which means it's just possible to use the open(mount_path, > O_PATH) to obtain the base fd. No, you can't. A path more correspond to multiple mounts stacked on top of each other, e.g.: mount -t tmpfs none /mnt mount -t tmpfs none /mnt mount -t tmpfs none /mnt Now you have three co-located mounts and you can't use the path to differentiate them. I think this might be an issue in autofs, but Ian would need to comment on that. David