$disposition = HTTP_DOWNLOAD_ATTACHMENT
$file_name = null
Set content disposition of the download.
"Content-Disposition" is not HTTP compliant, but most browsers follow this header, so it was borrowed from MIME standard. It looks like this: "Content-Disposition: attachment; filename=example.tgz".
string $disposition = HTTP_DOWNLOAD_ATTACHMENT - the disposition of the download (either 'attachment' or 'inline')
string $file_name = null - the file name the browser's download window should show
This function can not be called statically.