(PHP 4, PHP 5 < 5.3.0, PECL fdf SVN)
fdf_save — Save a FDF document
fdf_documentThe FDF document handle, returned by fdf_create(), fdf_open() or fdf_open_string().
filenameIf provided, the resulting FDF will be written in this parameter. Otherwise, this function will write the FDF to the default PHP output stream.