here is an example of what i want http://koleksi.pustakaskripsi.com/dl.php?f=12.pdf if you click the link in this page you will be redirected to download page, not the file but if you click the same link in the download page it will download the file that means all the files that are hosted on my site to be automatically redirected to the page where they were posted,when someone clicks on the download link on another site . when it clicks the download link on my site ,it should not be redirected . the redirection must work only when someone post the download link on other site