I think it is even worse than I thought...<p>I&#x27;ve asked the &quot;true&quot;-random tool to give me 3000 of the really &quot;true&quot; numbers (as it claims) and out of 3000 it has thrown to me ~9% of char(0) and ~9% of char(255) values (see the fractions below), whilst the others &lt;0.01% per char between char(1-254).<p><pre><code>  .&#x2F;generate_constant_stream |head -c3000 |ent -c
  Value Char Occurrences Fraction
  0              309   0.103000
  1               33   0.011000
  ...
  ...
  253   �           28   0.009333
  254   �           29   0.009667
  255   �          312   0.104000
  Total:          3000   1.000000

  Entropy = 6.861709 bits per byte.

</code></pre>
<i>Update</i><p>Running it without the char(0)&#x2F;char(255) neither did outperform &#x2F;dev&#x2F;urandom, but only running terribly slow (~5mins on i7) and using 100% of a CPU core:<p><pre><code>  $ .&#x2F;generate_constant_stream | cat - | sed -u &#x27;s&#x2F;\x00&#x2F;&#x2F;g;s&#x2F;\xff&#x2F;&#x2F;g&#x27; |head -c3000 |ent -c
  Entropy = 7.737683 bits per byte.

  $ cat &#x2F;dev&#x2F;urandom | sed -u &#x27;s&#x2F;\x00&#x2F;&#x2F;g;s&#x2F;\xff&#x2F;&#x2F;g&#x27; |head -c3000 |ent -c
  Entropy = 7.924493 bits per byte.</code></pre>