Re: [PATCH v7 0/7] Add O_DENY* support for VFS and CIFS/NFS

[Pavel Shilovsky]

2014/1/20 Volker Lendecke :
> > You can try to use O_PATH flag. It doesn't give you a delete access
> > but should be ok because further deleting will be done without file
> > descriptor -- through unlink syscall.
>
> Ok, I did not know about O_PATH. Thanks for that!
>
> So I do an open with O_PATH. How do I then make sure that
> nobody else has a O_DENYDELETE set without doing the unlink
> itself?

It's not possible with the current API to do it through open syscall.
Another possibility is to look at /proc/locks. But I think we really
need O_DELETE flag that will force a file to be removed on close - we
will be able to do O_DENYDELETE checks atomically.