En essayant exec() en local j'ai vu que mon application test se lançait mais que la page continue de s’exécuter si je ne ferme pas l'application...
Voilà, j'espère ne pas être trop vague.
Merci
If a program is started with this function, in order for it to continue running in the background, the output of the program must be redirected to a file or another output stream. Failing to do so will cause PHP to hang until the execution of the program ends.