fwrite writing from beginning without removing

Question

I am using PHP and fwrite code, but I want every write position to start from the beginning of the file without erasing it\'s content. I am using this code but it is writing

Answer 1

use this code :

$file = 'aaaa.txt';
$oldContents = file_get_contents($file);
$fr = fopen($file, 'w');
$newmsg="text".$oldContents;
fwrite($fr, $oldContents);
fclose($fr);