secure_random.rs

//! Safe cryptographic random number generation in Rust.
//! Works on Windows, Mac, Linux, FreeBSD, etc.
extern crate rand; // https://crates.io/crates/rand

use rand::{Rng};         // The generic trait all random generators support.
use rand::os::{OsRng};   // Specific implementation of above for strong crypto.

fn main() {
    // OsRng is a type of `Rng` that wraps /dev/urandom, getrandom(), etc.
    let mut r = OsRng::new().unwrap();

    // Random bytes.
    let mut my_secure_bytes = vec![0u8; 1500];
    r.fill_bytes(&mut my_secure_bytes);

    // Primitive types and short arrays.
    let my_secure_int: u64 = r.gen();
    
    println!("First few bytes = {:?}; random int = {:?}",
        &my_secure_bytes[..5], my_secure_int);
}