Php Stream - Write to temp stream and forcefully download file.

Php Stream - Write to temp stream and force user to download file.php

<?php 
// Set the limit to 50 MB.
        $fiveMBs = 50 * 1024 * 1024;
        $fp = fopen("php://temp/maxmemory:$fiveMBs", 'r+');
        fputs($fp, $couponString);

        // Read what we have written.
        rewind($fp);

        header('Content-Description: File Transfer');
        header('Content-Type: application/octet-stream');
        header('Content-Disposition: attachment; filename="' . ('coupons.txt') . '"');
        header('Expires: 0');
        header('Cache-Control: must-revalidate');
        header('Pragma: public');
//        header('Content-Length: ' . filesize($filepath));
        flush(); // Flush system output buffer
        echo stream_get_contents($fp);
        exit;