시간측정 :: gettimeofday

#include<sys/time.h>
#include<unistd.h>

int main()
{
	struct timeval start_time,end_time;
	int i,sumarith=0,sumshift=0;
	
	gettimeofday(&start_time, NULL);

	for(i=0;i<1024;i++) {
		sumarith = sumarith + 9999; 
	}
	gettimeofday(&end_time, NULL);
	printf("----sum= %d  %ld.%ld ----\n",sumarith,
(end_time.tv_sec-start_time.tv_sec), (end_time.tv_usec-start_time.tv_usec));
	
	gettimeofday(&start_time, NULL);
	sumshift = 9999 << 10; 
	gettimeofday(&end_time, NULL);

	printf("----sum= %d  %ld.%ld ----\n",sumshift,
(end_time.tv_sec-start_time.tv_sec), (end_time.tv_usec-start_time.tv_usec));

	return 0;
}