LinuxQuestions.org - throw_future

Hi,

I am facing std::__throw_future_error(int) () exception if i try to do std::future<bool>::get() ()

Note: this exception is thrown sometimes (2 out of 10 times)

here is my code snippet.

Code:



MyClass::MyClass()

{

  futureNotification = prom.get_future();

}



void* thread_Fun(void *arg)

{

  MyClass *ptr = (MyClass *)arg;



  bool notification = ptr->GetFutureNotification();

 

  if(notification)

  {

    // do relevant work.

  }

}



bool MyClass::GetFutureNotification()

{

  return futureNotification.get();

}



void MyClass::SetNotification()

{

  prom.set_value(true); 

}





class MyClass

{

    std::promise<bool> prom;

    std::future<bool> futureNotification;



  public :



    void SetNotification();  

    bool GetFutureNotification();  



    ...

};

Can anyone let me know why the exception is thrown? Also why this exception is thrown sometimes and not always?

Note : i set the notification (SetNotification) from my other module of program.

My thread function (thread_Fun) will be waiting for notification from GetFutureNotification, when once the promise value is set the thread gets unblocked and proceed with its execution.

I appreciate your support in this regard.