Best way to print a new line to a txt file ?

[Jmacp]

I have this, and want to add a new line after each entry, ...?

<?php
         
$val = $_GET['data']; 

$myFile = "testFile.txt";
$fh = fopen($myFile, 'a') or die("can't open file");

$stringData = $val;
fwrite($fh, $stringData);
          

fclose($fh); 
?>