Re: [bug-gnulib] Updates to poll module

[Paolo Bonzini]

> > +             do
> > +               r = ioctl (pfd[i].fd, FIONREAD, &avail);
> > +             while (r == -1 && (errno == EAGAIN || errno == EINTR));
> > +             if (avail < 0)
> > +               avail = 0;
> >     
>
> When ioctl returns -1, maybe because FIONREAD is not supported or so,
> this loops endlessly.
>   

How so?  Only for EAGAIN and EINTR.  If FIONREAD is supported, it will 
return EINVAL or something like that.
> > +                 errno = 0;
> >     
>
> What's the purpose of that? If recv() needs errro to be 0 upon entry,
> this statement should come before the recv() call. It cannot be needed
> for the caller, since at this point it is guaranteed that the function
> returns with "return rc;" which is positive.
>   
The idea is that we return POLLHUP or POLLERR, so having poll set an 
errno is misleading.  If a function is allowed to modify errno 
arbitrarily (as long as it returns a positive value) I'm ok with 
removing this line.

Ok to remove the errno = 0, and to leave as is the part you commented above?

Paolo