Comment 3 for bug 664178

You generally need to run it first with no redirection, if you haven't authenticated it before. Relying on stdin redirection here was probably a mistake.

But, since mass-sync is basically deprecated today and is just to clean up the odd case where somebody doesn't realise they can use syncpackage directly, I don't think it's worth rearranging its interface to fix this. I expect this script will be removed at some point in the next six months or so.