php本地连接mysql数据库

I try to make a simple IOS app that can connect to mysql database and read one table. But my php code does't work and really have no idea why, it's seems correct to me. The database is in a raspberry phpmyadmin server and the server works great. I will put my code here and please tell me what's wrong.

<?php

$host = "192.168.2.193";
$db = "produtos";
$user = "root";
$pass = "1234";

$connection = mysql_connect($host, $user, $pass);

if(!$connection)
{
die("Database server connection failed.");
}
else
{
//attempt to select the database
$dbconnect = mysql_select_db($db, $connection);

//check to see if we could select the database
if(!dbconnect)
{
       die("Unable to connect to the specified database!");
}
else
{
    $query = "SELECT * FROM produtos";
    $resultset = mysql_query($query, $connection);

    $records = array();

    //loop throught all our records and add them to our array

    while ($r = mysql_fetch_assoc($resultset))
    {
        $records[] = $r;
    }

    echo json_ecode($records);
    echo $resultset; 

}
}

?>

Based on the question:

use mysqli_connect rather than mysql_connect because mysql_connect is deprecated and will not work someday. Also what is the the error you are getting? change your die() statement to something more helpful die(mysqli_error($connection));

Based on your comment:

That error would suggest that you either A) don't have the right IP address or B) there is a network issue between your host server and the SQL server, is this code running on the same server that is hosting the SQL database? if so then you can probably just use localhost for your $host