我正在尝试开发一个函数，从特定目录中检索文件列表。但是，结果总是空。我可以执行什么检查？目录权限是否正确。
我试过关闭防火墙。我在CentOS服务器上运行代码。

function getFiles($Directory){

    $ftp_server = "123.123.123.123";
    $ftp_user = "User";
    $ftp_pass = "Password";
    $ftp_dir = "../magazines/"; //I have tried absolute path also

    $conn_id = ftp_connect($ftp_server);
    $login_result = ftp_login($conn_id, $ftp_user, $ftp_pass);

    if ((!$conn_id) || (!$login_result)) {
        die("Conexion error");
    }

    //ftp_set_option($conn_id, FTP_USEPASVADDRESS, false);  //I have tried this so
    ftp_pasv($conn_id, true);   //I have tried false also

    $directory = $ftp_dir . $Directory;
    $files = ftp_nlist($conn_id, $directory);

    if ($files) {
        //Do something...
    } else {
        ftp_close($conn_id);
        return "Files not found.";
    }
}

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