Timing script for running pure PHP to compare against an extension written in C

gistfile1.txt

<?php
$lines = file('/home/peter/php-7.4.1/Zend/zend_language_parser.c');

function string_reverse($input){
    $temp = '';
    for($iter = strlen($input);$iter > 0; $iter--){
        $temp = $temp . $input[$iter-1];
    }
    return $temp;
}

$started = microtime();
foreach ($lines as $line) {
    string_reverse($line);
}
$ended = microtime();
echo $ended - $started;