Hi Michael, 2 cents from me :). On Mon, Jul 29, 2019 at 10:30 PM Michael Kerrisk (man-pages) <mtk.manpages@xxxxxxxxx> wrote: > What would you think of something like this: > SO_SELECT_ERR_QUEUE (since Linux 3.10) > When this option is set on a socket, an error condition on > a socket causes notification not only via the exceptfds set > of select(2). Similarly, poll(2) also returns a POLLPRI > whenever an POLLERR event is returned. > > Background: this option was added when waking up on an > error condition occurred occured only via the readfds and Spurious 'occured' on the line above. > writefds sets of select(2). The option was added to allow > monitoring for error conditions via the exceptfds argument > without simultaneously having to receive notifications (via > readfds) for regular data that can be read from the socket. > After changes in Linux 4.16, in Linux 4.16, the use of this Duplicate 'Linux 4.16' here. > flag to achieve the desired notifications is no longer nec‐ > essary. This option is nevertheless retained for backwards > compatibility. > > ? I haven't looked at the kernel commit; just by reading the text, I'm not sure I understand the feature: is the idea to tell select() to notify you of errors when a read or write fails? That's what I understand from the sentence starting with "Background:". The next sentence, however, suggests it gives you the ability to only select() for errors, without caring for read/write fd events. Your description is definitely an improvement on the original text, but still somewhat ambiguous. > > Thanks, > > Michael > > > -- > Michael Kerrisk > Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ > Linux/UNIX System Programming Training: http://man7.org/training/
