libeio: discrepancy between the manual and the code

[Konstantin Osipov]

* Jonathan Neuschäfer <j.neuschaefer at gmx.net> [13/01/24 22:00]:
> > ssize_t
> > coeio_custom(ssize_t (*func)(va_list ap), ev_tstamp timeout, ...)
> > {
> >         struct coeio_task task;
> >         task.fiber = fiber;
> >         task.func = func;
> >         task.result = -1;
> >         va_start(task.ap, timeout);
> >         struct eio_req *req = eio_custom(coeio_custom_cb, 0,
> >                                          coeio_on_complete, &task);
> >         if (req == NULL) {
> >                 errno = ENOMEM;
> >         } else if (fiber_yield_timeout(timeout)) {
> >                 /* timeout. */
> >                 errno = ETIMEDOUT;
> >                 task.result = -1;
> >                 eio_cancel(req);
> 
> I think you need to yield here again, and wait for the on_complete
> callback to wake you up.

In case of gethostbyname() that would render timeouts basically
useless. But what I could do indeed, is in the event of timeout
delegate destruction of task resources to on_complete callback.

But if you unwind to the beginning of the thread, on_complete
callback is not invoked (at least judging by what I see in the
code, but contrary to what is written in the docs).

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