How to make available on a PC, the RANDOM and URANDOM successor SRANDOM?

Question

SRANDOM is a more random replacement for the not so random RANDOM. It can be SRANDOM was released first time, on end of 2020. Additional, the SRANDOM can used for a bigger range of counts than RANDOM. SRANDOM comes with Bash-5.1.

So its the question, how to update to bash 5.1 or gettin SRANDOM support by other way ?

RANDOM:

• 16-bit
• create data which are not so equally distributed

SRANDOM:

• SRANDOM manpage.
• 32-bit
• create data which are more equally distributed

What need to be installed or updated to make SRANDOM available on konsole of Ubuntu and how to install or update ?

And as an alternate for systems, which dont run bash 5.1 in future too, how to get and run the C code from SRANDOM implimentation in a bash script or on terminal ?

Answer 1

The source-code for SRANDOM is available here https://github.com/josenk/srandom and you should be able to install on Linux with kernel 3.10 or above.

Prerequisites

If you are into development or devops, you will probably have them already.

sudo apt install git make 

Download

The the source

mkdir your-srandom-source-code-dir
cd your-srandom-source-code-dir
git init
git clone https://github.com/josenk/srandom

Install

The combo manual listed here https://github.com/josenk/srandom#compile-and-installation - but a brief example including installing a pre-requisite package:

sudo apt update && sudo apt install kernel-devel

cd your-srandom-source-code-dir
make
make install

Use

You use SRANDOM as if it was an infinite file full of the desired random data, so for example, you can use it as a data-source for dd. But avoid using commands which don't limit the amount of data they read (like "cat"), as this can cause performance issues.

dd if=/dev/srandom count=1 bs=1M of=random-output.txt

Answer 2

On systems which still dont support SRANDOM, you can use the follow, as better alternate to RANDOM, until your system supports SRANDOM:

rnd="$((0x$(dd if=/dev/urandom of=/dev/stdout bs=4 count=1 status=none | xxd -p)))"

A it can be, SRANDOM will be faster.

One othe alternate are:

my_rnd=$(openssl rand 4 | od -DAn)

Answer 3

On systems which still dont support SRANDOM, you can build your own srandom replacement as follow:

srandom() {
   # should be random number from /dev/urandom
   # we take 4 bytes - one number 2^32
   echo "$((0x$(dd if=/dev/urandom of=/dev/stdout bs=4 count=1 status=none | xxd -p)))"
}

Answer 4

You can install by you application management, synaptics or by install the srandom supporting bash 5.1 p.e. on follow way:

wget http://ftp.gnu.org/gnu/bash/bash-5.1.tar.gz

tar xf bash-5.0.tar.gz

cd bash-5.1

./configure make

sudo make install