//window 提供的一个特性地址窗口扩展(address window extension)
//显示如何使用AWE

void TestUsetAWE()
{
    //frist reserve a 1MB  region for the address window
    ULONG_PTR ulRAMBytes = 1024 * 1024;
    PVOID pvWindow = VirtualAlloc(NULL, ulRAMBytes, MEM_RESERVE | MEM_PHYSICAL,
        PAGE_READWRITE);
    // Get the number of bytes in a page for this CPU platform
    SYSTEM_INFO sinf;
    GetSystemInfo(&sinf);
    //calculate the required number of RAM pages for the desired number of bytes
    ULONG_PTR ulRAMPages = (ulRAMBytes + sinf.dwPageSize - 1) / sinf.dwPageSize;
    //allocate array for RAM page's page frame numbers
    ULONG_PTR* aRAMPages = (ULONG_PTR*) new ULONG_PTR[ulRAMPages];

    //Allocate the pages of RAM (requires Lock Pages in memory user right)
    AllocateUserPhysicalPages(GetCurrentProcess(), //allocate the stirage for our process
        &ulRAMPages, //[in]:number of RAM pages [out]:number pages allocated
        aRAMPages);//[out]:opaque array indicating pages allocated
    //assign the RAM pages to pur window
    MapUserPhysicalPages(pvWindow,//the address og the address window
        ulRAMPages,//number of entries in array
        aRAMPages);//array of RAM pages

    //access the RAM pages via the pvWindow virtual address
        //..........
    //end access  free the block of RAM pages
    FreeUserPhysicalPages(GetCurrentProcess(),
        &ulRAMPages,
        aRAMPages);
    //destory the address window 
    VirtualFree(pvWindow, 0, MEM_RELEASE);
    delete[] aRAMPages;

}