user38775: If two people running vanitygen 1abcdefg What is the chance that both of the person will get the same public key & private key?
I hope that the answer is less than 0.0000001. But for this vanigygen need to use random algorithm (not simple while(true){ i++; test()}).
My question is: Usually when I create wallet, using http://bitaddress.org I need to Move your mouse around to add some extra randomness, but vanitgygen do not do this method.
By inspecting the code of vanitygen in GitHub I see that they use random functions. Can I trust it? Is it really random? How it can be secure? Is it use the machine time or what?

user85: 
If two people running vanitygen 1abcdefg What is the chance that both of the person will get the same public key & private key?

If a billion supercomputers each tried a billion keys per second for a billion years, the odds of a key collision would still be less than one in a billion.

I hope that the answer is less than 0.0000001.

Yes, much less.

But for this vanigygen need to use random algorithm (not simple while(true){ i++; test()}).

It just needs a random starting place. You can increment from there if you want to. The number of possible starting places has 77 digits when expressed in decimal notation.

38775: <p>If two people running <code>vanitygen 1abcdefg</code> What is the chance that both of the person will get the same public key &amp; private key?</p>

<p>I hope that the answer is less than <code>0.0000001</code>. But for this <code>vanigygen</code> need to use random algorithm (not simple <code>while(true){ i++; test()}</code>).</p>

<p><strong>My question is:</strong> Usually when I create wallet, using <a href="http://bitaddress.org" rel="nofollow">http://bitaddress.org</a> I need to <em>Move your mouse around to add some extra randomness</em>, but <em>vanitgygen</em> do not do this method.</p>

<p>By inspecting the code of <code>vanitygen</code> in GitHub I see that they use random functions. Can I trust it? Is it really random? How it can be secure? Is it use the machine time or what?</p>
 85: <blockquote>
  <p>If two people running vanitygen 1abcdefg What is the chance that both of the person will get the same public key &amp; private key?</p>
</blockquote>

<p>If a billion supercomputers each tried a billion keys per second for a billion years, the odds of a key collision would still be less than one in a billion.</p>

<blockquote>
  <p>I hope that the answer is less than 0.0000001.</p>
</blockquote>

<p>Yes, much less.</p>

<blockquote>
  <p>But for this vanigygen need to use random algorithm (not simple while(true){ i++; test()}).</p>
</blockquote>

<p>It just needs a random starting place. You can increment from there if you want to. The number of possible starting places has 77 digits when expressed in decimal notation.</p>
