Re: [RTnet-developers] Ethernet IP

[Anders B. <and...@co...>]

On 2011-02-08 15.49, Jan Kiszka wrote:
> On 2011-02-08 15:27, Glen Wernersbach wrote:
>> Jan,
>>
>> The project I am trying to make real time is:
>> http://sourceforge.net/projects/opener/
>>
>> It is hard to give a test case because my other side of this is an Allen
> 
> I'm primarily interested in the connection setup pattern which should be
> extractable into a set of two simple test applications.
> 
>> Bradley controller. This project does work in standard Linux but then I have
>> to deal with OS latencies from the card to my real time program.
>>
>> Here is my current thought. The code as written in your example works. If I
>> run accept() before select, accept() always returns the same file descriptor
>> as was put it. Is this a a limitation of RTNET?
> 
> Yes, see Documentation/README.tcp.
> 
>>
>> Also, it appear that select() without accept() and you can read()
>> successfully.
> 
> Are you implementing a server or a client? A server without accept would
> be weird, and a client with it just as well.
> 
>>
>> I can probably work around the above.
> 
> Wrong approach, likely doomed to blow up at a different end later on.
> 
>>
>> Now I need to focus on why Send or Write  are "oops"ing.
> 
> If you don't post it, you will have to parse it on your own...
> 
>>
>> The only difference between my code and your example is that I am not
>> setting the same socket options SO_KEEPALIVE and SO_SNDTIMEO. I will try
>> these this mourning.
>>
>> The only other reason this could be "oops"ing is that I am reading and
>> writing on the same socket and your example does not.
> 
> We do in a less trivial application in the field. No complains from my
> colleagues so far.
With raw sockets I have problems reading and writing from/to the same socket
when done from different threads (on my todo list to track this down some time
in the future), might this be the same problem?


> 
>>
>> I will let you know.
>>
>> Glen
>>
>> P.S. At least now I know I can go back to RTAI if I want. The rest of our
>> project works in RTAI.
> 
> OTOH, analysis is easier elsewhere.

/Anders

-- 
Anders Blomdell                  Email: and...@co...
Department of Automatic Control
Lund University                  Phone:    +46 46 222 4625
P.O. Box 118                     Fax:      +46 46 138118
SE-221 00 Lund, Sweden