每次加载时在temp文件上写入不同的值

I create a temp file by php the code is :

$filename = tempnam('/tmp', 'cre');
$fp = fopen($filename, 'w');
fwrite($fp, 'store temporary data in a file');
fclose($fp);
unlink($filename);

and include this file by :

$temp_file = tempnam(sys_get_temp_dir(), '');
echo $temp_file;

Now how can I write a rendom number on it for every user? And can I call this file from another page ? Like: a user come my site now it generated with a number code, I say user to go code.php with new tab here i call the tamp file by

$temp_file = tempnam(sys_get_temp_dir(), '');
echo $temp_file;

is it possible ?