Symfony\Component\Process\Process::setCommandLine PHP Method

    public function setCommandLine($commandline)
    {
        $this->commandline = $commandline;
        return $this;
    }

 /**
  * @When /^I run behat$/
  */
 public function iRunBehat()
 {
     $this->process->setWorkingDirectory($this->workingDir);
     $this->process->setCommandLine(sprintf('%s %s %s %s', $this->phpBin, escapeshellarg(BEHAT_BIN_PATH), strtr('--format-settings=\'{"timer": false}\'', array('\'' => '"', '"' => '\\"')), '--format=progress'));
     $this->process->start();
     $this->process->wait();
 }