C++之时间戳耗时对比

#include
#include 
#include 
#include 
#include 

int main(){
	struct timeval tv;
	unsigned long  sec_start,sec_end,ms_start,ms_end,us_start,us_end;
	//start time
	gettimeofday(&tv,NULL);
	sec_start = tv.tv_sec; //sec
	ms_start = tv.tv_sec*1000 + tv.tv_usec/1000; //ms
	us_start = tv.tv_sec*1000000 + tv.tv_usec; //us

	printf("sleep 2sn");
	sleep(2);	

	//end time
	gettimeofday(&tv,NULL);
	sec_end = tv.tv_sec; //sec
	ms_end = tv.tv_sec*1000 + tv.tv_usec/1000; //ms
	us_end = tv.tv_sec*1000000 + tv.tv_usec; //us

	printf("sec_delta = %ld sn",sec_end - sec_start);
	printf("ms_delta = %ld msn",ms_end - ms_start);
	printf("us_delta = %ld usn",us_end - us_start);
}