Symfony\Component\Process\Process::isTerminated PHP Method

    public function isTerminated()
    {
        $this->updateStatus(false);
        return $this->status == self::STATUS_TERMINATED;
    }

 /**
  * {@inheritdoc}
  */
 public function wait(Process $process)
 {
     $start = microtime(true);
     $end = $start + $this->timeout / 1000;
     while (!$process->isTerminated() && microtime(true) < $end) {
         usleep(self::TICK * 1000);
     }
     if ($process->isRunning()) {
         $callback = $this->callback;
         $callback();
     }
     $process->wait();
 }