How to tell if it is a development buid or release build

STRING* str_hour="";
STRING* str_minute="";
STRING* str_mode="";

TEXT* txt_date_info = 
{
	layer = 1;
	pos_x = 50;
	pos_y = 10;
	string (str_month,str_day,str_year,str_hour,str_minute,str_mode);
	flags = CENTER_X  | SHOW;
	
} 

function get_date()
{
	var file_handle=0;
	
	
		if(file_exists("date.txt"))
		{
		
		file_handle=file_open_read("date.txt");
		var i=0;
		for(i=0;i<6;i++)
		{
			
			file_str_read(file_handle,(txt_date_info.pstring)[i]);
		}
		
		if(run_mode > 7)
	{
		str_cpy((txt_date_info.pstring)[5],"RELEASE,");}
		file_close(file_handle);}
	
}

function store_date()
{
	if(run_mode>7)
	return;
	var file_handle=0;
	var dates[5];
	dates[0]=sys_month;
	dates[1]= sys_day;
	dates[2]=sys_year;
	dates[3]=sys_hours;
	dates[4]=sys_minutes;
	beep();
		file_handle=file_open_write("date.txt");
		var i=0;
		for(i=0;i<5;i++)
		{
			str_for_num((txt_date_info.pstring)[i], dates[i]);
			str_cat((txt_date_info.pstring)[i],",");
			file_str_write(file_handle,(txt_date_info.pstring)[i]);
		}
		str_cpy((txt_date_info.pstring)[5],"DEVELOPMENT,");
		file_str_write(file_handle,(txt_date_info.pstring)[5]);
		file_close(file_handle);
		get_date();	
}
function main()
{
  vec_set(screen_size,vector(800,400,0));
  vec_set(screen_color,vector(50,1,1)); // dark blue
  vec_set(sky_color,vector(50,1,1)); // dark blue
  video_window(NULL,NULL,0,"My New Game");
  d3d_antialias = 1;
  shadow_stencil = 3;
  
  level_load(NULL);
   
  vec_set(camera.x,vector(-250,0,50));
  vec_set(camera.pan,vector(0,-15,0));
	wait(1);
	on_p=store_date;
	get_date();
}

STRING* str_show_v="";
TEXT={string(str_show_v);flags|= SHOW;}

function main()
{
......
str_for_num(str_show_v,version);
}

var total=0;
var years= sys_year-1970; 
var month=sys_months
var day=sys_day; 
day=day*86400:
month=month*2592000;
year=year*31104000;
total=(year+month+day)-file_date; // ERROR var to long
// convert total back to hours or days
total/=86400;
//total should now be a var/fixed of days old the build is