accumulating thread count after calling mex file multiple times

I have written a mex function that opens a W32 window as a child to a matlab window. And a second function that closes this window.

After calling these functions repetitively (20+) without errors, matlab becomes unresponsive after 5 to 10 minutes. Even if i call drawnow in between the other calls. The only thing I notice is, that after each call to my mex functions the number of threads associated with matlab increases (>250).

I am not creating threads in my mex function and after creating a window in the first call, I reuse the handle to the window.

Question, why does matlab freeze after some time , and why is the number of threads increasing.

regards,

Chris

[Jan]

Without seeing the relevant part of the code, it is impossible to guess, what happens.

Answer 1

[Chris van der Togt]

I've not put any code because it would have been too much, but I think I have solved the issue.

The thing is that in addition to creating a w32 window (which is no problem at all), I was using this as a directx render target.

IN the initializing call of the directX device I obtained a pointer to the back buffer, but forgot to release the pointer. This leads to a silent increase of thread use in matlab, which ultimately leads it to hang.

     ID3D11Texture2D* pBackBuffer = NULL;
        hr = g_pSwapChain->GetBuffer( 0, __uuidof( ID3D11Texture2D ), ( LPVOID* )&pBackBuffer );
        if( FAILED( hr ) )
            return hr;         
    hr = g_pd3dDevice->CreateRenderTargetView( pBackBuffer, NULL, &g_pRenderTargetView );
      pBackBuffer->Release(); // * *critical part I forgot.**
        if( FAILED( hr ) )
            return hr;