Question

I am writing a class (virtual_flight_runtime_environment), and it is mostly non-static, with the exception of one static function for the purposes of a Win32 thread using it as its function. The class declares struct simaircraftdata* aircraftdata (a data struct), and calls ‘aircraftdata = new aircraftdata;’ in the constuctor (public: virtual_flight_runtime_environment()).

My question is about destructors and memory deallocation. I have written the destructor as such:

    ~virtual_flight_runtime_environment(void) {
         /*..Other code, i.e. closing win32 handles, etc.*/
        delete aircraftdata;
    }

Now, the class is declared in another function (the DoWork function of a .Net background worker) like so:

    virtual_flight_runtime_environment* this_environment = new virtual_flight_runtime_environment;

And just before the end of the function, I call ‘delete this_environment;’. Immediately after, ‘this_environment’ would have gone out of scope, and the desturctor should have been called.

Is this correct? I do notice continued increases in memory usage over time, and I’m wondering if I’ve done something wrong. Does calling delete on a pointer just make it a null pointer, or does it deallocate the data at the end of it?

Any advice would be appreciated,

Collin Biedenkapp

Answer 1

There is no direct connection between a delete in your program and whether it will directly be visible in say the task manager because the OS tries to optimize memory utilization. When you look in the task manager you will typically see the working set size of your application, this is a measure of how much memory your app has requested but not necessarily how much it is currently using.

And to your question, yes deleting the memory as you did it is the WTG although as others have pointed out using smart pointers is generally much better to handle memory to avoid later headaches.