<?php
echo "seconds passed since 01-01-1970 00:00 GMT is ".time();
?>

<?php
$test=require("test.php");
echo "the content of test.php is:<hr>".$test;
?>

<?php
function requireToVar($file){
    ob_start();
    require($file);
    return ob_get_clean();
}
$test=requireToVar($test);
?>

<?php
return 'abc';

$abc = include 'include.php';

ob_start();
include 'include.php';
$buffer = ob_get_clean();

<?php
    return 'seconds etc.';

<?php
    $text = include('file.php'); // just assigns value returned in file

return (function () {
    // Local variables (not exported)
    $current_time = time();
    $reference_time = '01-01-1970 00:00';

    return "seconds passed since $reference_time GMT is $current_time";
})();

return call_user_func(function(){
    // Local variables (not exported)
    $current_time = time();
    $reference_time = '01-01-1970 00:00';

    return "seconds passed since $reference_time GMT is $current_time";
});

$banner = require 'test.php';

$var = require '/dir/file.php';

<?php

function get_file($path){

    return eval(trim(str_replace(array('<?php', '?>'), '', file_get_contents($path))));
}

$var = get_file('/dir/file.php');

<?php
  //include.php file
  $return .= "value1 ";
  $return .= time();

<?php
  // other.php file
  function() {
    $return = "Values are: ";
    include "path_to_file/include.php";

    return $return;
  }

Values are: value1, 145635165