fwrite() not working ??

Question

<?php
$myfile = fopen("test25.txt", "rw") or die("Unable to open file!");
$text=intval(fgets($myfile));
if($text<=2)
{
$r=$text+1;
fwrite($myfile, strval($r));//fwrite doesn't write the file (no errors)
}

fclose($myfile);
?>

Answer 1

$myfile = fopen("test25.txt", "w")