Netwroking problem

Daron Chabot daron.chabot at
Wed Oct 7 19:38:44 UTC 2009

Sorry for posting twice, but the message that made it to the list is
NOT the entire message that I sent. Weird...

We'll try this again:

Hi Leon,

errno==11 maps onto EAGAIN.

>From the manpage, recv(2):
      These  are  some  standard errors generated by the socket layer.  Addi-
      tional errors may be generated and returned from the underlying  proto-
      col modules; see their manual pages.

      EAGAIN The  socket  is  marked  non-blocking  and the receive operation
             would block, or a receive timeout had been set and  the  timeout
             expired before data was received.

Does the frequency of the error occurrence scale inversely with the
timeout value ?

-- dc

On Wed, Oct 7, 2009 at 6:55 PM, Leon Pollak <leonp at> wrote:
> Hello,
> My application (PPC, rtems 4.8) receives data sent by PC (in this case) as UDP
> packages of 1400bytes. I have 1 second timeout set with
> setsockopt (so, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof tv)
> The PC sends data at about 800kB/s rate.
> Everything works fine for an arbitrary period of time.
> At some moment, my recvfrom operation exits with -1 while errno is set to 11.
> Then the operation continues and the error may occur again several times.
> When I check the traffic in wireshark sniffer I see that the largest interval
> between packets was about 40ms.
> What is the cause of this error 11?
> A lot of thanks ahead for a help.
> --
> Leon
> _______________________________________________
> rtems-users mailing list
> rtems-users at

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