// BACKUP CONFIG
    function BackupConfigFile()
    {
        // FUNCTIONS
            function tInsert(arr, str) // table insert (as last item for one-dimensional table)
            {
                var size = arr.length;
                arr[size] = str;
                return arr;
            }

            function tReverse(arr) // reverse table
            {
                for(i = 0; i < arr.length / 2; i++)
                {
                    temp = arr[i];
                    arr[i] = arr[arr.length - i - 1];
                    arr[arr.length - i - 1] = temp;
                }
                return arr;
            }

        // GET FILES
            var t_files = [];
            var f_config_main = "";
            var f_config_backup = "";
            var files = clr.System.IO.Directory.GetFiles("C:\\Users\\" + sysinfo.UserName + "\\AppData\\Roaming\\StrokesPlus.net\\");
            for(var i = 0; i < files.Length; i++)
            {
                var file = new FileInfo(files[i]);
                var name = file.Name; // name
                var date_time = file.LastWriteTime; // date time
                //var size = file.Length; // size
                if(name == "StrokesPlus.net.bin") { f_config_main = date_time; } // only main file
                else  if(name != "StrokesPlus.net.bin") // get only backup files
                {
                    f_config_backup = date_time; // file with newest date
                    tInsert(t_files, name);
                }
            }

        // PATHS
            var date = DateTime.Now.ToString().replace(/:/g, "."); // file cannot be saved with ":" in name
            p_SPlusNetMainFile = "C:\\Users\\" + sysinfo.UserName + "\\AppData\\Roaming\\StrokesPlus.net\\StrokesPlus.net.bin"
            p_SPlusNetBackupFile = "C:\\Users\\" + sysinfo.UserName + "\\AppData\\Roaming\\StrokesPlus.net\\StrokesPlus.net " + date + ".bin"

        // BACKUP
            if(f_config_main != f_config_backup) // some changes are made
            {
                File.Copy(p_SPlusNetMainFile, p_SPlusNetBackupFile); // feel safety
                var n_range = 10 // how many file must be saved
                if(t_files.length >= n_range) // delete too old file(s)
                {
                    tReverse(t_files); // reverse table
                    for(var i = (n_range-1); i < t_files.length; i++)
                    {
                        File.Delete("C:\\Users\\" + sysinfo.UserName + "\\AppData\\Roaming\\StrokesPlus.net\\" + t_files[i]);
                    }
                }
            }
    }