title: PHP: Truncate text at word boundaries
body: <p>Does anybody have the exact name of the function Drupal uses to turn the following string:</p>
  
  <p>"Hello, how are you. Some more text." </p>
  
  <p>into</p>
  
  <p>"Hello, how..."</p>
  
  <p>I.e. The function that's used to cut off a sentence after x words, and then add an elipsis. Alternatively, if anybody has a php snippet that does this, that would be great too!</p>