difftime返回值的单位是秒吗？
#include "stdlib.h"
#include "time.h"
int main(void)
{
time_t first, second;
first = time(NULL);
second = time(NULL);
printf("%f", difftime(second, first));
return 0;
}
#include <time.h>
#include <stdio.h>
int main(void)
{
time_t first, second;
first = time(NULL); /* Gets system time */
sleep(2); /* Waits 2 secs */
second = time(NULL); /* Gets system time again */
printf("The difference is: %f seconds\n",difftime(second,first));
return 0;
}
[root@bogon temp]# ./t1
The difference is: 2.000000 seconds
测试证明，返回的是秒
