Hi Juha,
Calling FD_SET(fd, &rset) after timeout solves the problem. Thanks for your
help.
Daniel Pereira de Carvalho
Em sex., 20 de nov. de 2020 às 14:41, Juha Niskanen (Haltian) <
juha.niska...@haltian.com> escreveu:
> From POSIX: "If the timeout interval expires without the specified
> condition being true for any of the specified file descriptors, the objects
> pointed to by the readfds, writefds, and errorfds arguments shall have all
> bits set to 0."
>
> If your select() timeouts on first loop iteration for any reason, then it
> will timeout forever as you give it back all-zeroes descriptor set to
> monitor.
>
> Best Regards,
> Juha Niskanen
>
>
> ________________________________
> From: Daniel Pereira Carvalho <daniel...@gmail.com>
> Sent: Friday, November 20, 2020 7:26 PM
> To: dev@nuttx.apache.org <dev@nuttx.apache.org>
> Subject: Re: select()/pselect() function
>
> I will try pool() and see if the problem persists.
>
> Thanks
>
> Daniel Pereira de Carvalho
>
>
> Em sex., 20 de nov. de 2020 às 14:18, Gregory Nutt <spudan...@gmail.com>
> escreveu:
>
> > Okay, I got that wrong. I seldom used select(), it is just an
> > additional layer on top of poll() which is much more efficient.
> >
> > On 11/20/2020 11:13 AM, Daniel Pereira Carvalho wrote:
> > > Hi Greg,
> > >
> > > Thanks for the answer. I don't understand why I should use 1 instead of
> > > fs + 1. The documentation says
> > >
> > > "nfds This argument should be set to the highest-numbered file
> descriptor
> > > in any of the three sets, plus 1. "
> > >
> > > In the portserial.c nfds was set to fd + 1
> > >
> > > Daniel Pereira de Carvalho
> > >
> > >
> > > Em sex., 20 de nov. de 2020 às 14:04, Gregory Nutt <
> spudan...@gmail.com>
> > > escreveu:
> > >
> > >>> fd = open("/dev/ttyS1", O_RDWR | O_NOCTTY);
> > >> ...
> > >>> s_rc = select(fd + 1, &rset, NULL, NULL, &tv);
> > >> The first argument should be 1, not fd + 1
> > >>
> > >>
> > >>
> >
>
