$username = $_POST['username'];
$password = $_POST['password'];
$remember = $_POST['remember'];

$foralogin = sprintf("SELECT * FROM users WHERE username='%s' AND password='%s'",
mysql_escape_string($username), mysql_escape_string(md5($password)));

$foralogged = mysql_query($foralogin) or die(mysql_error());

if (mysql_num_rows($foralogged) == 0) {
  echo("Error!");
} else {
  if (isset($remember)) {
    setcookie('username', $username, time+60*60*24*30*12, '/');
    header (sprintf("Location: ../index.php"));
  } else {
    $_SESSION['username'] = $username;
    header (sprintf("Location: ../index.php"));
  }
}