Question

I’m writing a console application Windows that creates some objects in the main thread and kicks those off into a loop, only exiting when the user uses the Ctrl-C interrupt.

Now, I’ve read a bit about how to write a proper interrupt handler in articles like this: http://msdn.microsoft.com/en-us/library/ms685049%28VS.85%29.aspx but I’m still confused about one thing. It seems like the interrupt handler leaves limited scope for local object cleanup. For instance, if I had a handler like so:

BOOL CtrlHandler ( DWORD fdwCtrlType )
  ... handle Ctrl-C 

and my main looked something like this:

int main() {
      DBClient db;
      DataPuller p;

      while (true) {
           ... do stuff until Ctrl-C comes in
      }

Even if I catch the Ctrl-C, there seems to be no way to do a proper cleanup of variables db and p without declaring them global, which I typically stay away from.

Is there a better way to do this, or am I missing something obvious? Thanks.

Answer 1

You make your loop on a condition variable.

When you receive ctrl-C (SIGINT) you set the condition variable to false and return.
The loop will then exit normally.

bool finished = false;

int main()
{
      DBClient db;
      DataPuller p;

      while (!finished)
      {
           // ... do stuff until Ctrl-C comes in
      }
}

// Signal handler or Control handler on windows
// Set finished = true.