d.cpp

利用VC编写的定时器程序

#include   <stdio.h>   
#include   <stdlib.h>   
#include   <time.h>   
    
void sleep(clock_t wait);   
    
void main()   
{   
    long i=600000L;   
	clock_t start,finish;   
	double  duration;   
	/*   Delay   for   a   specified   time.   */   
	printf(   "Delay   for   three   seconds\n"   );   
	sleep(   (clock_t)2* CLOCKS_PER_SEC   );   
	printf(   "Done!\n"   );   
    /*   Measure   the   duration   of   an   event.   */   
	printf(   "Time   to   do   %ld   empty   loops   is   ",   i   );   
	start =clock();   
	while(i--)     
		  ;   
	finish=clock();   
	duration=(double)(finish-start)/CLOCKS_PER_SEC;   
	printf("%2.1fseconds\n",duration );   
  }  
/*   Pauses   for   a   specified   number   of   milliseconds.   */   
void sleep(clock_t wait)   
{   
	clock_t goal;   
    goal=wait+clock();   
    while(goal>clock())   
		;   
}   
    
 /*   
  Output   
    
  Delay   for   three   seconds   
  Done!   
  Time   to   do   600000   empty   loops   is   0.1   seconds   
    
*/