On Sat, Feb 20, 2021 at 07:29:57PM +0000, Al Viro wrote: > And then you notice that it has reports > successful write of amount other than what you'd passed and tries > to pull back.
Sorry, half-edited sentence has escaped ;-/ Should be "And there the caller notices that callback has reported a successful write, but the amount apparently written is not the same as the amount it had asked to write. It interprets that as a short write and tries to pull back. Only it's actually _forward_, since we'd asked to write 0 bytes and got a small positive number from the callback."
