Direction error when using UDPReceiver on port 6666

I have a problem that I am unable to solve or to find an explanation for. Let's say I have a small useless code in file 'tmp.m':

udpr = dsp.UDPReceiver('LocalIPPort',6666,'MessageDataType','int8');
step(udpr);

I would like to run it now. If I do so using the Matlab IDE, the code is executed and I don't have any problem with it. However, if I want to run it using the Matlab Command Window (by using the command "start "Matlab" /b %myMatlabRute% -r "tmp" -nodesktop") I get the following error:

Error using UDPReceiver/step
Solo se permite un uso de cada dirección de socket (protocolo/dirección de red/puerto)

Error in tmp (line 2)
step(udpr);

The second line of the error would translate as "Each socket is allowed to be used in just one direction (protocol/direction of the network/port)".

Does anyone know why this could happen?

Answer 1

[Hari Desanur]

I ran the above "dsp.UDPReceiver" code in the "tmp.m" file from within the MATLAB IDE and then opened another session of MATLAB from the command line with the '-nodesktop' option.

Now if run the "tmp.m" function in the '-nodesktop' version I was able to see the error which you are getting. Then I closed the original MATLAB IDE session and ran the "tmp.m" file from within the '-nodesktop' version and I was not able to see the same error.

I think we are getting that error because when we run the 'tmp.m' file from both the '-nodesktop' and 'desktop' version of MATLAB at the same time we are trying to setup 2 receivers using the same port.

[Alejandro González]

You are absolutly right. Because I'm always working with both things open I didn't catch the problem. Thank you very much for your help