Performing I/O on ```BorrowedFd``` or ```BorrowedHandle``` objects with ```ManuallyDrop ```

Hello everyone! The OS-specific part of the Rust standard library contains types to contain a kernel object handle to work on raw OS resources and close them on drop (OwnedHandle and OwnedSocket for Windows and OwnedFd for Unix-like systems). These types have "borrowed" counterparts, which do not close the resource on drop and are lifetime-tied to the "resource-owning" object (BorrowedHandle and BorrowedSocket for Windows and BorrowedFd for Linux). I wonder, is it safe to perform I/O on Borrowe...