FileSystem API - overwrite flag for copy/move?

Hi,

I have a question about Entry.moveTo/copyTo behavior defined in
the File API: Directories and System [1].

Currently the API doesn't specify how Entry.moveTo() and copyTo() should
behave
when a source entry is a file and there's *already* a file at the
destination path.
Should UAs overwrite the existing file at the destination path or not?
Or maybe we should add an 'overwrite' flag to indicate if the script wants
to overwrite an existing file or not?

Similarly I wondered if we'd want to have a 'recursive' flag for
moveTo/copyTo.
I think for directories we can simply assume that the user wants to
move/copy
them recursively, but it might be good to add some notion about that in the
spec.

Thanks,

[1] http://dev.w3.org/2009/dap/file-system/file-dir-sys.html