Marcel Keller <> writes:

> Thomas P Jakobsen wrote:
>> If not, I guess we'll have to use some external package (openssl?) or
>> implement our own algorithm.
> viff.util.rand is used to make all randomness replayable, which
> already helped me to find bugs triggered by certain randomness. I
> would like to have this feature also in the future, therefore I would
> vote against a random number generator using noise not only to
> generate a seed.

Right, but note that the seed is not enough to ensure deterministic
output because of jitter in the network.

> If the environment variable VIFF_SEED is set to the empty string, VIFF
> already uses /dev/urandom by using random.SystemRandom for random
> number generation. This possibility is not documented however.

It's documented in the final paragraph here:

I will of course agree that it could be made more explicit :-)

Martin Geisler

Mercurial links:

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