extern"system"{#[link_name="SystemFunction036"]fnRtlGenRandom(pBuffer:*mutu8, cbBuffer:usize)->u32;}/// Obtain a random 64-bit number using WinAPI's `RtlGenRandom` function.
pubfnentropy(out:&mut [u8])->bool{unsafe{ RtlGenRandom(out.as_mut_ptr(), out.len())==0}}