All one really has to do is example in PHP

function stall_browser($records,$file){
  Header("Cache-Control: must-revalidate");
  $minutes = floor(round(($records * .82)/60,2));  //Calulated at .77
  $seconds = (round(($records * .82)/60,2)-$minutes) *60;
  $offset = 60 * 60 * 24 * 0;
  $ExpireString = gmdate("D, d M Y H:i:s", time() + $offset) . " GMT";
  Header("Expires: " . $ExpireString);
  echo "<META HTTP-EQUIV=Expires CONTENT=\"$ExpireString\">";

 {put what you would like to see here on the page}
 {flush}
 {feed a small bitstream until completed}
 for ($i=0;$i<2;$i++) echo str_repeat (' ',512) ."\n";

 {when finished send}
   echo "<div align='center'><a href='http://www.energywatchdog.com/usi/ind
  echo "</body>\n";
  echo "</html>\n";
  echo "<META HTTP-EQUIV=Refresh CONTENT=\"0; URL=http://www.energywatchdo
  exit;
};

The refresh redirect is to the new PDF file.  If you do this any other way
that I have tried it works in some browsers and not others this appears to
work in all broswers.

Patrick Lanphier
The Artemis Group
http://www.artemisgroup.com
phone: 814-235-0444
  fax: 800-582-9710

On Fri, 19 Apr 2002, Chris Faulkner wrote:

> Hi
>
> I'm using FOP in a JSP to return dynamically created PDF documents to 
> browsers. I'm using the usual method of embedding FOP as described on the web 
> site. It works great. The main problem is that the
> PDFs take about 20 seconds to generate and then, since they are 500K or so, a 
> while to download depending on connection speed.
>
> I'd like to be able to put a message on an intermediate page which could 
> refresh and only return the PDF when it is ready. At the moment, they are 
> just seeing a blank page until the PDF is complete. Does
> anyone have any ideas for this ? Can I flush some output to the page to 
> advise them to be patient, then reset the response and send the PDF when it 
> is ready?
>
> Alternatively. I was thinking of doing something a bit more ambitious which 
> would be to output the PDF to a database blob, then send back a page which 
> refreshes to a JSP which keeps checking whether
> the PDF has been finished. When it is, I could fetch the data outofthe BLOB 
> and send it back.
>
> I have seen other sites where the PDF was output to a static file on the 
> website. Then the JSP would refresh and keep checking until the file was 
> present. When the file was created, the page would
> appear with a link to the file. The main problem with this is security. There 
> is the potential that everyone would have access to all PDFs on the web site, 
> although on a site without listings, they'd need to be
> making pretty inspired guesses to find and download it.
>
> How do others get around this ? I imagine its quite a common problem.
>
> Thanks
>
>
> Chris
>
>

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