How to let a lab tell if another lab is idle or not in a spmd block at that time : isidle(labindex)

Hello,

Is there a way to let lab 2 know if a lab 1 is idle or not in a specific timepoint:

% an example (not related to reality, but for demo only, so please do not question the meaning. I know this demo is not that much useful)
spmd
    for i=1:100
        if labindex == 1
            try
                labSend(1,'hello,start')
                dosomething_ErrorProne_but_takes_less_than_2s();
                labSend(1,'succeed')
            catch
                break % if lab1 break and idle early,lab2 's labReceive(1) will catch error.
            end
        elseif labindex == 2
            msg1 = labReceive(1);
            disp(msg1);
            pause(3);% wait for lab1 finish
            enquiryLab = 1;
            if isidle(enquiryLab);
                % NOTE: if lab1 has that error in that function, lab1 will be idle immediately without sending data(a data can make lab2 not idle until sent), 
                    % later if lab2 call labReceive to an idle lab1, will be
                    % error: The other lab became idle during labReceive.
                    % so I need a isidle() to pre-check before call labReceive
                try
                    msg2 = labReceive(1); 
                catch ME

                end
                disp(['lab 1 result:', msg2]);
            end
        end
    end
end

Answer 1

[raym]

labProbe can solve this problem.

Answer 2

[Edric Ellis]

I can think of a few ways around this:

1. As you suggest, labProbe can tell you if there's an incoming message ready to be received
2. You could just call labReceive anyway. spmd (in the default setup) has error detection enabled that will cause the labReceive to throw an error if the worker for which it is waiting reaches the end of the spmd block without sending a message
3. You could use try/catch around just the error-prone function and then ensure that you always call labSend. You could choose to send different data to indicate that an error had been encountered.