Possible bug found in listArduinoLibraries()

Greetings,

I have followed the tutorial for the creation of a HelloWorld Arduino Addon Library. Upon completion I was unable to get the addon to register so I subsequently followed the documention for Custom Arduino Library Issues.

1.

clear classes

2.

rehash toolboxcache

Produces a warning:

Warning: Function license has the same name as a MATLAB built-in. We suggest you rename the function to avoid a potential name conflict.

3.

lib = listArduinoLibraries();

Produces a list of warnings and errors

Warning: The following error was caught while executing 'onCleanup' class destructor:
Output argument "status" (and possibly others) not assigned a value in the execution with "matlabshared.ddux/HWSDKDataUtility/dataUpdateImpl" function.

Error in matlabshared.internal.DataUtility/dataUpdate

Error in matlabshared.ddux.HWSDKDataUtilityHelper/integrateData

Error in listArduinoLibraries>@()integrateData(dduxHelper) (line 17)
c = onCleanup(@()integrateData(dduxHelper));
                 ^^^^^^^^^^^^^^^^^^^^^^^^^
Error in onCleanup/delete (line 25)
            obj.task();
            ^^^^^^^^^^
Error in listArduinoLibraries (line 72)
end
   ^ 
   

And of course, my HelloWorld addon doesn't register. Perhaps this potential bug might be the cause?

Cheers,

[Les Beckham]

If you see more than one entry when you execute this command at the Matlab command line, you should rename any that don't match what is shown below.

which -all license

built-in (/MATLAB/toolbox/local/license)

Or this, if you are on Windows (example with release 2024b):

built-in (C:\Program Files\MATLAB\R2024b\toolbox\local\license)

[Clayton Allen]

I'm starting to believe this issue is restricted to Matlab Online. It doesn't do this on my PC at home. And these symptoms did not start until I attempted to rehash...

[Les Beckham]

Interesting. Did you try which -all license in Matlab Online? The error messages that you showed seemed to indicate an issue with that command.

[Clayton Allen]

/MATLAB/toolbox/matlab/connector2/shadowfiles/shadows/license/license.m
built-in (/MATLAB/toolbox/local/license)                                 % Shadowed

Answer 1

[Sreeram]

Hi Clayton,

I also encountered the same warnings and errors when calling “listArduinoLibraries()” in MATLAB Online.

I fixed it by running the following snippet before calling “listArduinoLibraries()”:

system('mkdir -p overloads/+matlab/+ddux/+internal'); 
system (['echo -e "function status = logData(identification, varargin) \\n status = true; \\n end" > overloads/+matlab/+ddux/+internal/logData.m']); 
addpath('./overloads'); 

Regarding warning about ‘license’, I remember seeing in an older documentation of “rehash” that this functionality was not supported in MATLAB Online. This might be contributing to the unexpected behaviour.