Re: [libgpiod v2][PATCH v5] bindings: cxx: implement C++ bindings for libgpiod v2.0

[Bartosz Golaszewski <brgl@xxxxxxxx>]

On Sun, Mar 27, 2022 at 2:22 PM Kent Gibson <warthog618@xxxxxxxxx> wrote:
>

[snip]

>
> > +     ::gpiod::edge_event_buffer buffer;
> >
> >       for (;;) {
> > -             auto events = lines.event_wait(::std::chrono::seconds(1));
> > -             if (events) {
> > -                     for (auto& it: events)
> > -                             print_event(it.event_read());
> > +             if (request.wait_edge_event(::std::chrono::seconds(5))) {
> > +                     request.read_edge_event(buffer);
> > +
> > +                     for (const auto& event: buffer)
> > +                             print_event(event);
> >               }
> >       }
> >
>
> What is the purpose of the wait_edge_event() here?
> Wouldn't read_edge_event() block until the next event?
>
> This example should be minimal and demonstrate how the code should
> normally be used. e.g.
>
>         for (const auto& event: request.events_iter())
>                   print_event(event);
>

We're making the request's file descriptor non-blocking in the C
library. Do you think we should keep it in blocking mode?

I'm no longer sure why I did that honestly.

Maybe a request config flag for that?

Bart