Phpprojet/inc/core.php

<?php
session_start();

try {
    $mysql = new PDO('mysql:host=localhost;dbname=clyde','root','');
} catch (PDOException $e) {
    die('Une erreur est survenue lors de la connexion à la base de données : ' . $e->getMessage());
}


function isLogged()
{
    global $mysql;
    if(!isset($_SESSION['login']) or !isset($_SESSION['password'])){
        return false;
    }
    $query = $mysql->prepare('SELECT * FROM users WHERE login = :login');
    $query->bindValue(':login', $_SESSION['login'], PDO::PARAM_STR);
    $query->execute();
    $data = $query->fetch(PDO::FETCH_BOTH);
    if ($data['password'] == $_SESSION['password']) // Acces OK !
    {
        $query->CloseCursor();
        return true;
    }
    $query->CloseCursor();
    return false;
}