Function wait

src/process.cpp:4040–4066

bool wait(const UPID& pid, const Duration& duration)
{
  process::initialize();

  if (!pid) {
    return false;
  }

  // This could result in a deadlock if some code decides to wait on a
  // process that has invoked that code!
  if (__process__ != nullptr && __process__->self() == pid) {
    LOG(ERROR) << "\n**** DEADLOCK DETECTED! ****\nYou are waiting on process "
               << pid << " that it is currently executing.";
  }

  if (duration == Seconds(-1)) {
    return process_manager->wait(pid);
  }

  bool waited = false;

  WaitWaiter waiter(pid, duration, &waited);
  spawn(waiter);
  wait(waiter);

  return waited;
}


void filter(Filter* filter)