> > let's define "file was removed" first.
> > 
> > 	1. whenever link count is decremented.
> > 	2. when link count reaches 0.  ie. disappeared from namespace.
> > 	3. when the last reference is closed after #2.
> > 	4. other?
> > 
> > i think #3 is reasonable, and if so, sys_unlink is not a right place.
> 
> i'll ask it another way: where do you suggest placing the hook that is
> not fs-specific?

(assuming #3 is reasonable for your purpose)
i don't think we have a good place in filesystem independent code.
in the case of ufs, the condition is checked in ufs_inactive().

YAMAMOTO Takashi