title: c++ generate a good random seed for psudo random number generators
body: <p>I am trying to generate a good random seed for a psudo-random number generator.  I thought I'd get the expert's opinions.  let me know if this is a bad way of doing it or if there are much better ways.</p>
  
  <pre><code>#include &lt;iostream&gt;
  #include &lt;cstdlib&gt;
  #include &lt;fstream&gt;
  #include &lt;ctime&gt;
  
  unsigned int good_seed()
  {
      unsigned int random_seed, random_seed_a, random_seed_b; 
      std::ifstream file ("/dev/random", std::ios::binary);
      if (file.is_open())
      {
          char * memblock;
          int size = sizeof(int);
          memblock = new char [size];
          file.read (memblock, size);
          file.close();
          random_seed_a = int(memblock);
          delete[] memblock;
      }// end if
      else
      {
          random_seed_a = 0;
      }
      random_seed_b = std::time(0);
      random_seed = random_seed_a xor random_seed_b;
      return random_seed;
  } // end good_seed()
  </code></pre>