manual reset과 auto reset의 차이점에 대해

// ----------------------------------------------------------------------------
// VEvent
// ----------------------------------------------------------------------------
class VEvent
{
protected:
  QMutex         m_mutex;
  QWaitCondition m_cond;
  bool           m_manualReset;
  bool           m_state;
 
public:
  VEvent(bool manualReset = false, bool initialState = false);
  virtual ~VEvent();
 
public:
  bool state() { return m_state; }
  void setEvent();
  void resetEvent();
  bool wait(unsigned long timeout = ULONG_MAX);
};

// ----------------------------------------------------------------------------
// VEvent
// ----------------------------------------------------------------------------
VEvent::VEvent(bool manualReset, bool initialState)
{
  m_manualReset = manualReset;
  m_state       = initialState;
}
 
VEvent::~VEvent()
{
}
 
void VEvent::setEvent()
{
  m_mutex.lock();
  m_state = true;
  m_cond.wakeAll();
  m_mutex.unlock();
}
 
void VEvent::resetEvent()
{
  m_state = false;
}
 
bool VEvent::wait(unsigned long timeout)
{
  m_mutex.lock();
  bool res = true;
  if (!m_state)
  {
    res = m_cond.wait(&m_mutex, timeout);
  }
  if (!m_manualReset) m_state = false;
  m_mutex.unlock();
  return res;
}