tempname() not working on client server
Warning: ftp_rawlist() [function.ftp-rawlist]: Unable to create temporary file. Check permissions in temporary files directory.

define ("LOCALFILE",tempnam('/tmp', 'data-'));
define ("USER","myusername");
define ("PASS","mypassword");
define('SERVER', "ftpserver.com");
define ("DIR","/path/");

function getFTPFile(){

    // connect
    if(!($conn_id = @ftp_connect(SERVER))){
        Error::throwOne("Could not connect to ".SERVER);

    };
    // login
    if(!($login_result = @ftp_login($conn_id, USER, PASS))){
        Error::throwOne("LOGIN INCORRECT! user:".USER." pass:".PASS);
    };
    // try to change the directory to somedir
    if (!ftp_chdir($conn_id, DIR)) {
        Error::throwOne("Couldn't change directoryn");
    };

    if(!($a = ftp_rawlist($conn_id, '-1t'))){
        Error::throwOne("Couldn't get ftp_rawlistn");
    };

    $server_file=($a[0]);
    if (!ftp_get($conn_id, LOCALFILE, $server_file, FTP_BINARY)) {
        Error::throwOne("Couldn't get filen");
    };
    ftp_close($conn_id);
};

$tmpdir = sys_get_temp_dir();
echo "Temp dir: $tmpdirn";
echo  is_writable($tmpdir) ? "Temp dir is writable" : "Temp dir is not writable";