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PO/dev/random permission denied
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copied!<p>I was reading about random numbers and their generation. I was interested in randomness since I started programming. I read that Linux Kernels also use random number generating architectures. </p> <pre><code>The structure consists of a two-level cascaded sequence of pools coupled with CSPRNGs. Each pool is a large group of bits which represents the current state of the random number generator. The CSPRNGs are currently based on SHA-1, but the kernel developers are considering a switch to SHA-3. The kernel RNG produces two user-space output streams. One of these goes to /dev/urandom and also to the kernel itself; the latter is useful because there are uses for random numbers within the kernel. The other output stream goes to /dev/random. The difference between the two is that /dev/random tries to estimate how much entropy is coming into the system, and will throttle its output if there is insufficient entropy. By contrast, the /dev/urandom stream does not throttle output, and if users consume all of the available entropy, the interface degrades to a pure CSPRNG. </code></pre> <p>So, full with excitement I tried to enter and check whats there in the /dev/random and /dev/urandom. But it said, </p> <pre><code>root@ubuntu:/home/sunny# /dev/random bash: /dev/random: Permission denied root@ubuntu:/home/sunny# /dev/urandom bash: /dev/urandom: Permission denied </code></pre> <p>However, when I check with "ls" command, I can see "random" there in /dev. I would like to know this in detail.</p>

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