Question

Digital commercial products that customers pay for download link.

I have put all the zipped files (products) outside of web document root and buyers download them via a php script which is integrated with paypal IPN to make sure the downloader is a paying buyer.

Sort of like: http://www.mysite.com/download.php?buyer_id=xxx

Thus far it all works with only one problem. The zip files I download via the URL above is corrupted and can’t be opened correctly with WinRAR. However, directly downloaded zip is fine.

My code:

$path = WAREHOUSE_PATH.'/products/'.$identifier.'.zip'; $mm_type='application/octet-stream'; header('Pragma: public'); header('Expires: 0'); header('Cache-Control: must-revalidate, post-check=0, pre-check=0'); header('Cache-Control: public'); header('Content-Description: File Transfer'); header('Content-Type: ' . $mm_type); header('Content-Length: ' .(string)(filesize($path)) ); header('Content-Disposition: attachment; filename=''.basename($path).'''); header('Content-Transfer-Encoding: binary\n');  $fp = @fopen($path,'rb'); if ($fp) {   while(!feof($fp)) {     print(fread($fp, 1024*8));     flush();     if (connection_status()!=0) {       @fclose($fp);       die();     }   }   @fclose($fp); } 

What could be wrong? Thanks!

Problem solved: Thank you all for the tips. It turns out that the downloaded packages contains a few extra white spaces which shouldn’t be there. Silly.

Answer 1

You’d be better off just using readfile(). Unless you have ignore_user_abort on, then the script will terminate automatically if the user cancels anyway.

If you’re still having problems, load the file up in a hex editor and compare the first few characters and the last few characters.