Struct rand::OsRng

[+] Show declaration

pub struct OsRng(_);

[−] Expand description

A random number generator that retrieves randomness straight from the operating system. Platform sources:

• Unix-like systems (Linux, Android, Mac OSX): read directly from /dev/urandom, or from getrandom(2) system call if available.
• OpenBSD: calls getentropy(2)
• FreeBSD: uses the kern.arandom sysctl(2) mib
• Windows: calls RtlGenRandom, exported from advapi32.dll as SystemFunction036.
• iOS: calls SecRandomCopyBytes as /dev/(u)random is sandboxed.
• PNaCl: calls into the nacl-irt-random-0.1 IRT interface.

This usually does not block. On some systems (e.g. FreeBSD, OpenBSD, Max OS X, and modern Linux) this may block very early in the init process, if the CSPRNG has not been seeded yet.[1]

[1] See https://www.python.org/dev/peps/pep-0524/ for a more in-depth discussion.

Methods

impl OsRng[−]

pub fn new() -> Result<OsRng, Error>[−]

Create a new OsRng.

Trait Implementations

impl Debug for OsRng[+]

[+] Show hidden undocumented items

fn fmt(&self, f: &mut Formatter) -> Result<(), Error>[−]

Formats the value using the given formatter.

impl Rng for OsRng[+]

[+] Show hidden undocumented items

fn next_u32(&mut self) -> u32[−]

Return the next random u32.

fn next_u64(&mut self) -> u64[−]

Return the next random u64.

fn fill_bytes(&mut self, v: &mut [u8])[−]

Fill dest with random data.

fn next_f32(&mut self) -> f32[−]

Return the next random f32 selected from the half-open interval [0, 1).

fn next_f64(&mut self) -> f64[−]

Return the next random f64 selected from the half-open interval [0, 1).

fn gen<T>(&mut self) -> T where
    T: Rand, [−]

Return a random value of a Rand type.

fn gen_iter<T>(&'a mut self) -> Generator<'a, T, Self> where
    T: Rand, [−]

Return an iterator that will yield an infinite number of randomly generated items.

fn gen_range<T>(&mut self, low: T, high: T) -> T where
    T: SampleRange + PartialOrd<T>, [−]

Generate a random value in the range [low, high).

fn gen_weighted_bool(&mut self, n: u32) -> bool[−]

Return a bool with a 1 in n chance of true

fn gen_ascii_chars(&'a mut self) -> AsciiGenerator<'a, Self>[−]

Return an iterator of random characters from the set A-Z,a-z,0-9.

fn choose<T>(&mut self, values: &'a [T]) -> Option<&'a T>[−]

Return a random element from values.

fn choose_mut<T>(&mut self, values: &'a mut [T]) -> Option<&'a mut T>[−]

Return a mutable pointer to a random element from values.

fn shuffle<T>(&mut self, values: &mut [T])[−]

Shuffle a mutable slice in place.