title: Merge FDF data into a PDF file using PHP
body: <p>Is it possible to merge FDF data with a PDF file using PHP alone?  Or is there no option but to use a 3rd party command line tool to achieve this?</p>
  
  <p>If that is the case can someone point me in the direction of one?</p>
  
  <p>I am currently outputting the FDF file to the browser in the hope that it will redirect the user to the filled in PDF but for some people that is not the case. The FDF contents is being output to the screen, even though I am using header('Content-type: application/vnd.fdf');</p>