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From: Luuk <luuk@invalid.lan>
Newsgroups: gnu.bash.bug
Subject: Re: $RANDOM not Cryptographically secure pseudorandom number generator
Date: Wed, 2 Jan 2019 12:01:45 +0100
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On 2-1-2019 02:29, Ole Tange wrote:
> On Mon, Dec 31, 2018 at 8:12 PM Chet Ramey <chet.ramey@case.edu> wrote:
> :
>> Thanks for the patch. I'll take a look after I release bash-5.0. One
>> question: can you reproduce the same random sequence by using the same
>> seed? That's for backwards compatibility, even if the sequences themselves
>> differ.
> 
> Yes. Seeding with a value will give the same sequence:
> 
> $ RANDOM=4; echo $RANDOM $RANDOM
> 21584 22135
> 
> $ RANDOM=4; echo $RANDOM $RANDOM
> 21584 22135
> 

But not across systems:
luuk@WINDOWS:/mnt/c/Windows/System32$ RANDOM=4;echo $RANDOM $RANDOM
1692 27588
luuk@WINDOWS:/mnt/c/Windows/System32$ RANDOM=4;echo $RANDOM $RANDOM
1692 27588

luuk@opensuse:~> RANDOM=4; echo $RANDOM $RANDOM
32221 21043
luuk@opensuse:~> RANDOM=4; echo $RANDOM $RANDOM
32221 21043