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Date: Mon, 8 Jan 2024 15:55:35 +0100
To: cygwin@cygwin.com
Subject: Re: /dev/u?random implementation
Message-ID: <ZZwM552P8iaSJJzM@calimero.vinschen.de>
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From: Corinna Vinschen via Cygwin <cygwin@cygwin.com>
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On Dec 20 16:32, Jim Garrison via Cygwin wrote:
> I dug around in the Cygwin doc looking for details on how /dev/random
> and /dev/urandom are implemented, but came up empty.  Is this
> documented anywhere?

Not documented as such, it's a "use the source, luke" kind of
information.

/dev/random is implemted by calling RtlGenRandom().

/dev/urandom is implemted by calling RtlGenRandom() and, if that fails
(which is extremly unlikely) it falls back to a very simple PRNG.


Corinna

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