Re: Fwd: [bug #17877] Invalid "No such file or directory" error on filesystem without stable inode numbers

[Jim Meyering]

Miklos Szeredi <address@hidden> wrote:
>> > This one should work, since the file descriptor in the working
>> > directory should prevent the inode from going away.  Or is there
>> > something I'm missing?
>>
>> We like to have a way of searching a directory hierarchy 100000 levels
>> deep without needing to have 100000 open file descriptors.
>
> No, you only need _one_ file descriptor for the current directory.
> That will hold a reference to all indodes above that in the tree,
> which is what you need to be able to detect a cycle.

But what about symlinks?

  a       g
   b       h->a
    c
     f->g

The moment you traverse the f->g symlink above,
the entire tree, a/b/c/f, is no longer referenced,
so the h->a link may take you back to a new inode,
and the cycle will not be detected.