> >         The question can be posed simply:  If a file is open for
> >         writing by at least one program, does NFS prevent that
> >         file from being deleted?  
> 
> This should be, but the mess starts, when two process try to lock at the
> same time. And the stability of nfs daemons is something varying.

	Seems that this could be boiled down to a simple program
	that can hammer away at a filesystem relentlessly, to
	test the "sequentiality" of the protocol.  I figure that
	if two processes try to delete the same file, one of them
	MUST fail.  (Assuming that the file exists, and nothing
	has a lock on it)

> It is. And there are quite some folks that have something like this
> around. I don't have anything handy but the pvm-stuff.  As this is
> digging the source, it's a bit out of your scope I think. 

	You're right - I should check out other projects in this
	direction.  But I think this question is quite pertinent
	to POVray, since it implies that a clustered render-farming
	solution for POVray could be bolted onto the next official
	release, quite cheaply.   No PVM, no big design effort, just
	a simple model for small networks...  ...that also fits 
	larger scale efforts....

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