[OpenAFS] Using callbacks for file locking?

[Mike Fedyk]

Hi,

Here is my current (probably flawed) understanding of callbacks.

When the cache manager (CM) connects to a RW volume, it sets a callback 
for that file to be notified to invalidate its local copy if another CM 
writes to the file.  Kinda like Oplocks in the SMB/CIFS world.

So, why couldn't callbacks also propagate and invalidate flock/fcntl locks?

Yes, I know AFS doesn't support byte range locking, and the architecture 
doesn't support database files.  What I'm looking for is being able to 
know when another user has a file opened/locked on a different machine, 
so that OpenOffice/etc. will open the file RO.

Is this possible with AFS on two different client machines?

Thanks,

Mike