On 2016-05-05 13:30:42 +1200, Thomas Munro wrote:
> That was a red herring. I was confused because SUSv2 and POSIX call
> this argument 'errorfds' and say that sockets *also* tell you about
> errors this way. (Many/most real OSs call the argument 'exceptfds'
> instead and only use it to tell you about out-of-band data and
> possibly implementation specific events for devices, pseudo-terminals
> etc. If you want to know about errors on a socket it's enough to have
> it in readfds/writefds, and insufficient to have it only in
> errorfds/exceptfds unless you can find a computer that actually
> conforms to POSIX.)
Correct, exceptfds is pretty much meaningless for anything we do in
postgres. We rely on select returning a socket as read/writeable if the
socket has hung up. That's been the case *before* the recent
WaitEventSet refactoring, so I think we're fairly solid on relying on
that.
Greetings,
Andres Freund