If you try and delete a file which is mid-move from one disc/filesystem to another, XP will think for a few seconds (it tries a few times with a pause between) and then tell you it can't be deleted.

And whilst you could open the file that is being moved (up until it is deleted as the coup de grace of the move, obviously), you could not save any changes you made to it.

XP allows reads but not writes to files being moved (and copied).

Which to my mind makes perfect sense -- more sense than preventing reads as well, although I'll grant I don't know why OSX seems to do that.

I'd like to believe it's for some sound technical reason, as Simon postulates, but personally I feel it's more likely to be because it's not been thought through properly, or not considered important enough to make right. There's stacks of stuff like that in both OSX and Windows.

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