try/catch with timeout

I have an instruction block with communication to external components, enclosed in try/catch. However, instead of throwing an exceptionand skipping to the "catch" part, the execution simply stalls under certain conditions. Is there any way top realize something like

try (max execution time x seconds)
    instructions with possible stall
catch ME
    will be executed either if instructions within try throw an exception or their execution takes more than x s
end

[Rik]

As far as I'm aware, this is only possible by spawning a new process, which then needs to signal to the main process that it is done by writing a file or something similar.

Answer 1

[Harsh Mahalwar]

Hi Lionel,

As there are several parts to this question, I will be solving it iteratively.

1. Running an external application/component from MATLAB.

This can be achieved by using the start command along with the “system” function in MATLAB.

2. Waiting x seconds for the application’s process to end.

This can be achieved by using timeout or PING commands along with “system” function in MATLAB.

Here's a workaround which uses "system" function of MATLAB along with start and ping commands in Windows to achieve the same:

line1 = convertCharsToStrings('start "" "C:\Users\harsh\Desktop\Demo.txt"'); 
line2 = "PING -n 6 127.0.0.1>nul"; 
line3 = convertCharsToStrings('taskkill /F /FI "WindowTitle eq Demo - Notepad" /T >> "logs.txt"'); 
try 
    % opens the demo.txt file 
    system(line1); 
    % timeout of 5 seconds 
    system(line2); 
    % tries to kill the process and creates logs.txt with it's output. 
    system(line3); 

    % Read the log.txt  
    output = readlines("logs.txt"); 
    logOutput = convertStringsToChars(output(1, 1)); 

    % If the first 7 characters are eq to 'Success' that would mean that 
    % our script had to terminate the process. 
    if logOutput(1:7) ~= 'SUCCESS' 
        disp("Process was closed on time!"); 
    else 
        error("Process Terminated!"); 
    end 
catch exception 
    disp(['Error: ' exception.message]); 
end 

(Note that this workaround is valid for Windows only)

You can learn more about “system” function in MATLAB using the following documentation:

https://www.mathworks.com/help/matlab/ref/system.html

I hope this helps, thanks!

[Lionel Pöffel]

Thanks for providing the input.

My question was posed a long time ago, so we had to find another work-around in the meantime, which was to systematically avoid the root-cause for the stalling mentioned above.

If your answer would be applicable to our use case is not fully clear, because we used the MATLAB Excel connection, so the system command may not have worked.

But it is a good approach that can help in other circumstances.