The fdf_open() function opens
a file with form data. This file must contain the data as returned
from a PDF form. Currently, the file has to be created 'manually'
by using fopen() and writing the content
of HTTP_FDF_DATA with fwrite() into it.
A mechanism like for HTML form data where for each input
field a variable is created does not exist.
Example 1. Accessing the form data
<?php
// Save the FDF data into a temp file
$fdffp = fopen("test.fdf", "w");
fwrite($fdffp, $HTTP_FDF_DATA, strlen($HTTP_FDF_DATA));
fclose($fdffp);
// Open temp file and evaluate data
$fdf = fdf_open("test.fdf");
...
fdf_close($fdf);
?>
