Linux函数localtime和time使用整理
localtime函数计算用时：
#include<sys/time.h>
#include<stdio.h>
#include <unistd.h>
int main()
{
unsigned long long used_time;
struct timeval begin, end;
//struct timezone tz;
//gettimeofday (&tv , &tz);
gettimeofday (&begin , NULL);
sleep(3);
gettimeofday (&end , NULL);
used_time = (end.tv_sec * 1000 + end.tv_usec / 1000);
used_time -= (begin.tv_sec * 1000 + begin.tv_usec / 1000);
printf("used :%.3lf\n", used_time / 1000.00);
return 0;
}
time+localtime转换为当前时间：
int main(void)
{
time_t timer;//time_t就是long int 类型
struct tm *tblock;
timer = time(NULL);
tblock = localtime(&timer);
printf("Local time is: %s/n",asctime(tblock));
return 0;
}
使用time计算用时：
#include <stdio.h>
#include <stddef.h>
#include <time.h>
#include <unistd.h>
int main(void)
{
time_t begin, end;//time_t就是long int 类型
struct tm *tblock;
begin = time(NULL);
sleep(3);
end = time(NULL);
printf("used time:%ld\n", end-begin);
return 0;
}