Hi Tycho, Thanks for getting back to me. On Mon, 26 Oct 2020 at 14:54, Tycho Andersen <tycho@tycho.pizza> wrote: > > On Mon, Oct 26, 2020 at 10:55:04AM +0100, Michael Kerrisk (man-pages) wrote: > > Hi all (and especially Tycho and Sargun), > > > > Following review comments on the first draft (thanks to Jann, Kees, > > Christian and Tycho), I've made a lot of changes to this page. > > I've also added a few FIXMEs relating to outstanding API issues. > > I'd like a second pass review of the page before I release it. > > But also, this mail serves as a way of noting the outstanding API > > issues. > > > > Tycho: I still have an outstanding question for you at [2]. > > [2] https://lore.kernel.org/linux-man/8f20d586-9609-ef83-c85a-272e37e684d8@xxxxxxxxx/ > > I don't have that thread in my inbox any more, but I can reply here: > no, I don't know any users of this info, but I also don't anticipate > knowing how people will all use this feature :) Yes, but my questions were: [[ [1] So, I think maybe I now understand what you intended with setting POLLOUT: the notification has been received ("read") and now the FD can be used to NOTIFY_SEND ("write") a response. Right? [2] If that's correct, I don't have a problem with it. I just wonder: is it useful? IOW: are there situations where the process doing the NOTIFY_SEND might want to test for POLLOUT because the it doesn't know whether a NOTIFY_RECV has occurred? ]] So, do I understand right in [1]? (The implication from your reply is yes, but I want to be sure...) For [2], my question was not about users, but *use cases*. The question I asked myself is: why does the feature exist? Hence my question [2] reworded: "when you designed this, did you have in mind scenarios here the process doing the NOTIFY_SEND might need to test for POLLOUT because it doesn't know whether a NOTIFY_RECV has occurred?" Thanks, Michael -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/
