Code:
function read_settings()  // save user defined settings to file
{
	file_handle = file_open_read("settings.ini");	// open settings file
	
	if (file_handle) // only continue if file exists, else use default settings
	{	
	video_screen = file_var_read (file_handle); // set video_screen	
	video_mode	=	file_var_read (file_handle);//set resolution
	video_gamma = file_var_read (file_handle); // set video_gamma to value from file
	master_vol = file_var_read (file_handle); // set master_vol to value from file
	camspeed = file_var_read (file_handle);
	file_close(file_handle); // close the file, we don't need it again
   }
   else { return;} // else stop loading and use default values
}

function write_settings()  // save user defined settings to file
{
	file_handle = file_open_write ("settings.ini");		
	file_var_write (file_handle, video_screen);
	file_var_write (file_handle, video_mode);
	file_var_write (file_handle, video_gamma);
	file_var_write (file_handle, master_vol);
	file_var_write (file_handle, camspeed);
	file_close(file_handle);
}

//use default opts
	video_gamma = 100; 
	master_vol = 100;
	video_screen = 1;
	video_mode = 9;
	camspeed	= 6;
	
	read_settings();


i found this in some post