Matlab onCleanup with Compiled applications (windows)

Question

I have an application made with matlab compiler.
I want to do some shutdown activities whenever it ends. As it seems to be impossible to catch signals in matlab (or I'm not able to), I checked to use onCleanup (Matlab: Is it possible to create signal handlers (.m scripts)). It is working within matlab (native), but not within the compiled application.
I tried to end the application with CTRL-C and with taskkill (which only work with /f). In both cases the onCleanup-method was NOT executed.
For testing purposes here

function sigtest(varargin)
remainder=onCleanup(@()save('exit.mat'));
b=1;
while true
    disp(datestr(now));
    a=rand(round(5*b));%to be saved
    pause(10);
    b=a(1);
end

my source code, which I compiled via mcc -m -v sigtest.m.
As onether try, I inserted the lines

myexiter=addlistener(System.AppDomain.CurrentDomain,'ProcessExit',...
    @(a,b)save('listexit.mat'));

after line 2, but also this .NET-Event is not working.

Answer 1

If you're registering shutdown activities within M-code, they're only going to work on a graceful shutdown of the process. The taskkill /f command will do a "forceful" shutdown, which I think will terminate the process immediately. The Matlab interpreter won't get a chance to run whatever cleanup code is still pending. I think Ctrl-C on a console application (which the compiled sigtest.m will be running as) will have the same effect. Same applies to the .NET-Event: if you forcefully kill the process, that callback never gets a chance to run.

If you want on-exit code, or any other cleanup stuff, to run, you need to find a way for the program to find out when it should exit and initiate a more graceful shutdown itself. For example, in your sigtest example, you could check stdin at the end of every pass through the loop, see if the user has typed 'quit', and if so call exit(). Then your onCleanup stuff should run.

In a GUI compiled Matlab application, this is more straightforward; you have GUI controls to exit the application. I don't know what the canonical way is to make a console compiled Matlab application responsive to user exit requests, or if there even is a good one. You might want to make this a GUI app if you think the user might want to request a graceful abort of its operation.