pub fn fclonefileat<Fd: AsFd, DstFd: AsFd, P: Arg>( src: Fd, dst_dir: DstFd, dst: P, flags: CloneFlags ) -> Result<()>
fclonefileat(src, dst_dir, dst, flags)—Efficiently copies between files.
fclonefileat(src, dst_dir, dst, flags)