获取系统毫秒时间的两种方法

unsigned long clockGetTimeHaoMiao2()
{
    struct timespec stv;
    clock_gettime(CLOCK_MONOTONIC, &stv);
    unsigned longt haoMiao = stv.tv_sec * 1000 + stv.tv_nsec /1000000;
    return haoMiao;
}

//FROM UTC1970-1-1 0:0:0
unsigned long clockGetRealTimeHaoMiao()
{
    struct timespec stv;
    clock_gettime(CLOCK_REALTIME, &stv);
    unsigned long haoMiao = stv.tv_sec * 1000 + stv.tv_nsec /1000000;
    return haoMiao;
}

CLOCK_MONOTONIC （系统开机开始算）  

CLOCK_REALTIME（现实真实时间，FROM UTC1970-1-1 0:0:0）