<?php include("header.php");
//username and password sent from form
$myusername=$_POST['user'];
$mypassword=$_POST['pass'];
// To protect MySQL injection (more detail about MySQL injection)
//$myusername = stripslashes($myusername);
//$mypassword = stripslashes($mypassword);
//$myusername = mysql_real_escape_string($myusername);
//$mypassword = mysql_real_escape_string($mypassword);
$myusername = strip_tags(stripslashes($myusername));
$mypassword= strip_tags(stripslashes($mypassword));
$en=enc($mypassword);
$sql="SELECT * FROM $tbl_name WHERE user='$myusername' and pass='$en'";
$result=mysql_query($sql);
// Mysql_num_row is counting table row
$count=mysql_num_rows($result);
// If result matched $myusername and $mypassword, table row must be 1 row
if($count==1){
    // Register $myusername, $mypassword and redirect to file "login_success.php"
    $_SESSION['user']=$myusername;
    $_SESSION['pass']=$mypassword;
    if (headers_sent()) {
        echo "<script type = 'text/javascript'> document.location = 'start.php'; </script>";
    }
    else {
        header("Location: start.php");
    }
}
?>