title: Generate dummy files in bash
body: <p>I'd like to generate dummy files in bash. The content doesn't matter, if it was random it would be nice, but all the same byte is also acceptable.</p>
  
  <p>My first attempt was the following command:</p>
  
  <pre><code>rm dummy.zip;
  touch dummy.zip;
  x=0;
  while [ $x -lt 100000 ];
  do echo a &gt;&gt; dummy.zip;
    x=`expr $x + 1`;
  done;
  </code></pre>
  
  <p>The problem was its poor performance. I'm using GitBash on Windows, so it might be much faster under Linux but the script is obviously not optimal.</p>
  
  <p>Could you suggest me a quicker and nice way to generate dummy (binary) files of given size?</p>