Issues with testing custom events with PHP

I created an custom event and downloaded the codes. Without doing anything, I tried to do a ./ and got the following error:
Fatal error: Call to undefined function backendless\core\pcntl_signal() in /Users/Alexander/projects/swipeey/TestApp/core/CodeRunner.php on line 32
Any advice on how to fix this error would be appreciated.

Hi! Could you try to use latest version of php code runner?