"Retrieves the calling thread's last-error code value. The last-error code is maintained on a per-thread basis. Multiple threads do not overwrite each other's last-error code. Visual Basic: Applications should call err.LastDllError instead of GetLastError." #Win32API
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MapViewOfFile function (memoryapi.h) - Win32 apps
GetLastError function (errhandlingapi.h) - Win32 apps
