Execute Callback Function Multiple Times isnt working in a executable (EXE) but in MATLAB its working

Hi,

i have a code which starts a EXE. Then a function checks every 3 seconds if the EXE is still runing (looking into tasklist and a .mat). If EXE is not running and a value is 0 then restart the EXE or close the program. In MATLAB everyhing works fine but when i make a executable it isnt working. It stops after one loop / iteration. Its never checks every 3 seconds if the EXE is running. Enclosed you find both log files (for the MATLAB and for the executable).

%start logging
diary myDiaryFile
fprintf('start Matlab program and logging! %s\n',datestr(now,'HH:MM:SS.FFF'));

%start EXE
system('C:\Users\christian\Desktop\TEST\EXE\Digitale_Ablegeschablone.exe &');
fprintf('start EXE %s\n',datestr(now,'HH:MM:SS.FFF'));

%wait time till EXE is loaded & open
pause(7)

%timer definition
t=timer;
t.period=3;
t.TasksToExecute=inf;
t.ExecutionMode='fixedRate';
t.TimerFcn=@checking;
start(t);
n=1;

%function for checking of EXE is running
function checking(t,~)
fprintf('function is working %s\n',datestr(now,'HH:MM:SS.FFF'));

%load .mat from EXE
load('C:\Users\christian\Desktop\TEST\Parameter.mat');
fprintf('load .mat from EXE %s\n',datestr(now,'HH:MM:SS.FFF'));

%check in tasklist if EXE is running
[~,b]=system('tasklist');
IsRunning=contains(b,'Digitale_Ablegeschablone');
fprintf('check in tasklist if EXE is running %s\n',datestr(now,'HH:MM:SS.FFF'));
    
    %if EXE is not running then check variables value in .mat
    if IsRunning(~0)
        if Save_Session==1
            fprintf('Variable Save_Session is 1 (on). Stop program %s\n',datestr(now,'HH:MM:SS.FFF')); 
            stop(t)
        elseif Block_beendet==1
            fprintf('Variable Block_beendet is 1 (on). Stop program %s\n',datestr(now,'HH:MM:SS.FFF'));
            stop(t)
        else
            fprintf('EXE is already open! %s\n',datestr(now,'HH:MM:SS.FFF')');  
        end
    else
            %Start EXE again 
            system('C:\Users\christian\Desktop\TEST\EXE\Digitale_Ablegeschablone.exe &')
            fprintf('start EXE again %s\n',datestr(now,'HH:MM:SS.FFF'));  
    end
end


 

[Rik]

Did you check the output of the system call when running in your compiled exe?

[tomy]

What you mean in detail? How I can check it

[Rik]

Something is different between your code running in Matlab, and your code running in the compiled exe. One possibility is what the system call returns, as that is the backbone of your code.

I would personally write to an actual log file, whose name I would create with tempname. You chose to use the diary function instead, but you should still be able to see what text is contained in the b char array.

Answer 1

[Walter Roberson]

You create the timer, and then you end the program. Your code "falls off" the end of the script. As far as MATLAB Compiler is concerned, that means that it is time to terminate the executable.

When you execute this code in MATLAB, after the timer is created, your code returns to the MATLAB Command Line and sits at the command line until interrupted by the timer (or the user.) But there is no MATLAB Command Line for .exe to return to.

You need to either code a loop to keep MATLAB alive, or else you need to waitfor() or uiwait() to keep MATLAB running but listening for events.

[tomy]

thank you for the good explanation about my problem. How to keep Matlab alive with a loop in my code? Thank You so much

[Walter Roberson]

while true
    pause(inf)
end

[tomy]

sorry and where do I put the while true? around the function or directly after if IsRunning(~0). I am still a beginner and don't know exactly. Thanks

[Walter Roberson]

after n=1;

You do not use n so I am not sure why you initialize it.

Question: under what circumstances should your exe terminate?

[tomy]

thank its working. n=1 is a leftover from old code...

my exe is a python livestream program which randomly crahses after some hours of use. I want that this will automatic restart if this happens.

One problem with pause(inf) is that the executable never closes (must kill it with taskmanager?). How to avoid this?

[Walter Roberson]

You have not defined a condition under which the code should volunteer to terminate

[tomy]

is this OK or is there a better way with better performance and low CPU-Load? So i dont really need a function? I can all do within the while true? Thank You

while true
     if Save_Session==1 | Block_beendet==1
         break
     end
         pause(inf)   
end

[Rik]

It is probably a better idea to call your timer function in the while loop, and use a pause with a small value.

while true
    CheckIfRunning
    
    % use drawnow in this function to parse any callbacks and update graphics
    [Save_Session,Block_beendet] = LoadUserInteractionFlags;
    
    if Save_Session || Block_beendet
        break
    end
    
    % Wait a few seconds before rechecking.
    pause(3)
end

Answer 2

[Seth Furman]

I should mention that datestr is discouraged. Prefer datetime where possible.

For example,

dt = datetime("now","Format","HH:mm:ss.SSS")

dt = datetime
   15:45:11.683

string(dt)

ans = "15:45:11.683"