recieve values from php server to arduino

how to receive values from php server to arduino using HTTP POST?
we have saved the audio files on sd card
and the user will send a token value from android app that we have designed and that should be played on arduino
on a speaker

we are using gsm shield and not ethernet shield

here is the arduino code to communicate with the server

numdata=inet.httpPOST("Vehicletracking.com.nu", 80, "/voicem.php", shortbuf, rst, 50);

and here is the server side php code

<?php 
if($_POST)
{
error_reporting(E_ALL);
$server="localhost";
$user="";
$pass="";
$database="";
$connection=mysql_connect($server,$user,$pass);
if(!$connection)
{
die('could not connect:'.mysql_error());
}
mysql_select_db($database,$connection);

$sqlString = "SELECT arg FROM message WHERE srno=(SELECT MAX(srno) FROM `message`);";
$result=mysql_query($sqlString,$connection);
$ARG=$result;

$sqlString1 = "DELETE * FROM message;";
$result1=mysql_query($sqlString1,$connection);
$val=$result;
echo $val;
if($result)
{
echo $ARG;
}
else
{
echo "error in inserting data:".mysql_error();
}
mysql_close($connection);
}
?>