title: Terminal passing arguments from variable containing whitespace
body: <p>In terminal how to pass a string as param that contains whitespace . It actually skips the part coming after whitespace and only takes the first word .</p>
  
  <pre><code>$word = 'soccer ball'
  shell_exec('casperjs test.js --word='.$word);
  </code></pre>
  
  <p>So how can I escape the whitespace it only runs this command</p>
  
  <pre><code>casperjs test.js --word=soccer
  </code></pre>