Hi,

> Can YAFFS detect this situation and effectively "unlink" the file first?

No, it should not. If the power is cycled between the unlink and open you will 
end up with no file at all. This is not an expected behaviour. It is ok to 
unlink and open from your application as long as you understand the 
repercussions but IMHO it is not ok to do it behind the scene.

Sergei