用clock函数测试机器catch的作用

/*
** 测试catch的程序
*/
#include <stdio.h>
#include <string.h>
#include <time.h>

#define DUMBCOPY for(i = 0; i < 65536; i++) /
destination[i] = source[i]

#define SMARTCOPY memcpy(destination, source, 65536)

int main()
{
char source[65536], destination[65536];
int i, j;
clock_t m, n;

m = clock();

for(j = 0; j < 100; j++)
{
DUMBCOPY;
}

n = clock();

printf("%f/n", (float)n - (float)m);

return 0;
}