System Entropy

randomstate.entropy.random_entropy(size=None, source='system')

Read entropy from the system cryptographic provider

Parameters:

• size (int or tuple of ints, optional) – Output shape. If the given shape is, e.g., (m, n, k), then m * n * k samples are drawn. Default is None, in which case a single value is returned.
• source (str {'system', 'fallback'}) – Source of entropy. ‘system’ uses system cryptographic pool. ‘fallback’ uses a hash of the time and process id.

Returns:

entropy – Entropy bits in 32-bit unsigned integers

Return type:

scalar or ndarray

Notes

On Unix-like machines, reads from /dev/urandom. On Windows machines reads from the RSA algorithm provided by the cryptographic service provider.

This function reads from the system entropy pool and so samples are not reproducible. In particular, it does NOT make use of a RandomState, and so seed, get_state and set_state have no effect.

Raises RuntimeError if the command fails.