Andres Freund <andres@anarazel.de> writes:
> I found a few more resources confirming that FD_CLOSE is edge
> triggered. Which probably doesn't just make our code buggy when waiting
> twice on the same socket, but probably also makes it very timing
> dependent: As the event is only triggered when the close actually occurs
> it's possible that we don't have any event associated with that socket:
> We only do so for shorts amount of time in WaitLatchOrSocket() and
> pgwin32_waitforsinglesocket().
Does the timing dependence explain why we've not been able to trigger this
by killing psql?
If the bug only occurs when the client connection drops when we're not
waiting for input, that would likely explain why nobody noticed it for
ten months.
regards, tom lane