problems with loading a url to send a txt msg

[p_tru]

i'm trying to send a text message using a url but it doesn't seem to be working and i can't see errors in my coding, can someone help me i would be very grateful.


[code]
<?php
//connect to database
include 'db.private';
        
       $connection = mysql_connect($hostname,$username,$pwd)or die(mysql_error());
       mysql_select_db($databaseName, $connection)or die(mysql_error());

SESSION_START();
if ($_SESSION[validated] == "yes") {//a
    

if (isset($_POST['Submit'])) {//b


$user = "john";
$password = "boy";
$api_id = "198";
$baseurl ="http://api.clickatell.com";
$text = urlencode("You have successfully booked your seat");
$to = "44784552";
// auth call
$url = "$baseurl/http/auth?user=$user&password=$password&api_id=$api_id";
// do auth call
$ret = file($url);
// split our response. return string is on first line of the data returned
$sess = split(":",$ret[0]);
if ($sess[0] == "OK") {//c
$sess_id = trim($sess[1]); // remove any whitespace
$url = "$baseurl/http/sendmsg?session_id=$sess_id&to=$to&text=$text";
// do sendmsg call
$ret = file($url);
$send = split(":",$ret[0]);
if ($send[0] == "ID")
    echo "success<br>message ID: ". $send[1];
    else
    echo "send message failed";
    } //c
    else {
    echo "Authentication failure: ". $ret[0];
    exit();
      }
}//b
//a
}else {
    echo "you have not logged in";
}
?>
[/code]