How to extract variable values ​​of another file without including it?

Question

css

<?php
header("Location: http://php.net"); #headers_Sent.php
headers_sent($filename, $linenum);
exit;

?>

<?php
$f = fopen('headers_Sent.php', 'r');  #headers_Sent1.php
fread($f, filesize('headers_Sent.php'));
echo $filename;

In short, how do I use the $filename variable in another file without redirecting to the php.net site ?

Answer 1

Remove the "active" class from the parent block

Answer 2

file_get_contents('php.net')?

Answer 3

Get the contents of the file as text and parse the desired piece with a regular expression.

Answer 4

return a json array of variables, but what's the point of doing it within the same site?