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#include <windows.h>
 
TCHAR GWndname[] = TEXT("GETMINMAXINFO");
TCHAR GAppname[] = TEXT("GetMinMaxInfo");
 
#define MIN_X_SIZE 640
#define MIN_Y_SIZE 400
LONG minX = MIN_X_SIZE;
LONG minY = MIN_Y_SIZE;
 
LONG  m_cxMin;
LONG  m_cyMin;
LONG  m_fyMin;
LONG  m_fxMin;  
 
void SetMinSize(LONG x, LONG y)
{
    m_cxMin = x;
    m_cyMin = y;
    m_fxMin = 2*(GetSystemMetrics(SM_CXFRAME)+
              GetSystemMetrics(SM_CXEDGE))   +
              m_cxMin;
    m_fyMin = 2*(GetSystemMetrics(SM_CYFRAME)+
              GetSystemMetrics(SM_CYEDGE))   +
              GetSystemMetrics(SM_CYCAPTION) +
              GetSystemMetrics(SM_CYMENU)    +
              m_cyMin;
}
 
LRESULT CALLBACK WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    LRESULT retval=0;
    switch(uMsg)
    {
    
    case WM_CREATE:
        SetMinSize(minX, minY);
        break;
    
    case WM_GETMINMAXINFO:
        {
            MINMAXINFO* mmi = (MINMAXINFO*)lParam;
            mmi->ptMinTrackSize.x = m_fxMin;
            mmi->ptMinTrackSize.y = m_fyMin;
        }
        break;
 
    case WM_CLOSE:
        DestroyWindow(hWnd);
        break;
    case WM_DESTROY:
        PostQuitMessage(0);
        break;
    default:
        retval=DefWindowProc(hWnd, uMsg, wParam, lParam);
        break;
    }
    return retval;
}
 
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
    WNDCLASSEX wc;
    wc.cbSize        = sizeof(WNDCLASSEX);
    wc.style         = CS_HREDRAW|CS_VREDRAW;
    wc.lpfnWndProc   = (WNDPROC)WndProc;
    wc.cbClsExtra    = 0;
    wc.cbWndExtra    = 0;
    wc.hInstance     = (HINSTANCE)hInstance;
    wc.hIcon         = LoadIcon(NULL,IDI_APPLICATION);
    wc.hCursor       = LoadCursor(NULL,IDC_ARROW);
    wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
    wc.lpszMenuName  = NULL;
    wc.lpszClassName = GWndname;
    wc.hIconSm       = LoadIcon(NULL,IDI_APPLICATION);
    if( !RegisterClassEx(&wc) ) {
        MessageBox(NULL,TEXT("Could not RegisterClass"),GAppname,MB_ICONSTOP|MB_OK);
        return 1;
    }
    HWND hWnd = CreateWindowEx(WS_EX_CLIENTEDGE,GWndname,GAppname,WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT,CW_USEDEFAULT,720,480,NULL,NULL,hInstance,NULL);
    if( hWnd==NULL ) {
        MessageBox(NULL,TEXT("Could not CreateWindow"),GAppname,MB_ICONSTOP|MB_OK);
        return 1;
    }
    ShowWindow(hWnd,nCmdShow);
    UpdateWindow(hWnd);
    MSG Msg;
    while(GetMessage(&Msg,NULL,0,0)>0) {
        TranslateMessage(&Msg);
        DispatchMessage(&Msg);
    }
    return (int)Msg.wParam;
}