简单的C++的定时器代码

#include<stdio.h>
#include<graphics.h>
#include<math.h>
#include<dos.h>
#include<bios.h>
#include<ctype.h>
#include<process.h>
#include<conio.h>
#define INTERRUPT 0x1c
int alpha,beta,gama,min;
struct time t;
union REGS i,o;
void(interrupt far * old_handler)();
void hand(int alpha,int pointer,int clr);
void hand(int alpha,int pointer,int clr)
{ int x,y;
  int ro;
  for(ro=-10;ro<=pointer;ro++)
     { x=ro*cos(alpha*3.14/180)+320;
       y=ro*sin(alpha*3.14/180)+240;
       putpixel(x,y,getpixel(x,y));
     }
  //重画指针
  setfillstyle(SOLID_FILL,YELLOW);
  circle(320,240,2);
  floodfill(320,240,YELLOW);
}
//时钟中断服务程序
void interrupt far handler()
{  static int time1=0,timer=0;