/**
  * Executes all ready cron tasks.
  *
  * If verbose mode is set, an info message will be printed if there is no task to
  *		be run, or else for each starting task.
  *
  * @see execute
  * @param InputInterface $input The input stream used to get the argument and verbose option.
  * @param OutputInterface $output The output stream, used for printing verbose-mode and error information.
  * @return int 0
  */
 protected function run_all(InputInterface $input, OutputInterface $output)
 {
     $run_tasks = $this->cron_manager->find_all_ready_tasks();
     if ($run_tasks) {
         foreach ($run_tasks as $task) {
             if ($input->getOption('verbose')) {
                 $output->writeln('<info>' . $this->user->lang('RUNNING_TASK', $task->get_name()) . '</info>');
             }
             $task->run();
         }
     } else {
         if ($input->getOption('verbose')) {
             $output->writeln('<info>' . $this->user->lang('CRON_NO_TASK') . '</info>');
         }
     }
     return 0;
 }