Salve ragazzi, ho trovato questo script sul come eseguire un backup del db, lo script funziona benissimo, il problema sta nel fatto che io al momento del backup non voglio far selezionare la cartella di salvataggio ma far salvare sempre nelle stessa cartella 
lo script è il sequente:
codice:
<?php
set_time_limit(0);
error_reporting(E_ALL);
define('DB_SERVER', 'localhost');
define('DB_USER', '');
define('DB_PASS', '');
define('DB_NAME', '');
define('DB_FILE', 'Backup' . date("d_m_Y__\hH_\mi", time()) . '.sql');
define('DB_DROP', $_GET['drop'] == '1');
define('DB_IGNORE', $_GET['ignore'] == '1');
define('DB_DATA', $_GET['data'] == '1');
define('DB_STRUCTURE', $_GET['struc'] == '1');
define('INSERT_QUERIES', 100);
if (!DB_DROP && !DB_IGNORE && !DB_DATA && !DB_STRUCTURE) exit;
$db = mysql_connect(DB_SERVER, DB_USER, DB_PASS) or die('Errore MySQL: ' . mysql_error() . ' (' . mysql_errno() . ')');
mysql_select_db(DB_NAME);
function datadump($table)
{
global $db;
$dump = @mysql_query("SELECT * FROM `$table`;", $db);
if (@mysql_num_rows($dump) <= 0)
return '';
$result = "";
$insert_fields = "";
$stack = array();
$colonne = @mysql_query("SHOW COLUMNS FROM `$table`;");
$cols = array();
while ($col = @mysql_fetch_object($colonne))
{
$cols[$col->Field] = $col->Null;
$insert_fields .= "`" . $col->Field . "`, ";
}
$insert_fields = substr($insert_fields, 0, -2);
while ($d = @mysql_fetch_assoc($dump))
$stack[] = $d;
foreach ($stack as $i => $val)
{
if (!($i % INSERT_QUERIES))
{
if (strlen($result))
$result = substr($result, 0, -2) . ";\n";
$result .= "INSERT " . ((DB_IGNORE) ? 'IGNORE ' : '') . "INTO `$table` ($insert_fields) VALUES ";
}
$result .= "(";
foreach ($val as $key => $value)
{
if ($value == NULL)
{
if ($cols[$key] == "YES")
$result .= 'NULL, ';
else $result .= "'', ";
}
else $result .= "'" . mysql_real_escape_string($value, $db) . "', ";
}
$result = substr($result, 0, -2) . "), ";
}
return substr($result, 0, -2) . ";\n";
}
header("Content-type: application/octet-stream");
header("Content-Disposition: attachment; filename = " . DB_FILE);
$query = "SHOW TABLE STATUS FROM `" . DB_NAME . "`;";
$tabelle = @mysql_query($query, $db);
echo 'SET SQL_MODE="NO_AUTO_VALUE_ON_ZERO";' . "\n\n";
while ($tab = @mysql_fetch_object($tabelle))
{
if (DB_STRUCTURE)
{
if (DB_DROP)
echo "DROP TABLE IF EXISTS " . $tab->Name . ";\n";
$query = "SHOW CREATE TABLE `" . $tab->Name . "`;";
$create = @mysql_query($query, $db);
$create = @mysql_fetch_assoc($create);
echo $create["Create Table"] . ";\n\n";
}
if (DB_DATA)
echo datadump($tab->Name) . "\n\n";
}
?>
so che devo modificare gli header ma non so come