Linux下获取ms的时间

    
      void getCurrentTime(tm *iCurrentTime,long &iMilliSecond)
      {
           timeval tv; 
	   time_t timep;

	   gettimeofday(&tv, NULL);//获取当下精确的s和us的时间
	   time(&timep);//获取从1900年至今的秒数
	   iCurrentTime = gmtime(&timep); //注意tm_year和tm_mon的转换后才是实际的时间
	   iCurrentTime->tm_year += 1900;
	   iCurrentTime->tm_mon  += 1;

	   iMilliSecond = (tv.tv_sec*1000.0 + tv.tv_usec / 1000.0) - timep * 1000.0; //当前ms数
      }

    void setSystemTime(tm iCurrentTime,long &iMilliSecond)
    {
        int iRet ;
        timeval tv;

        time_t curtime = mktime(&iCurrentTime); //转化为1900年至今的秒数
        tv.tv_sec = curtime;
        tv.tv_usec = lMilliSecond * 1000;
        iRet  = settimeofday(&tv,NULL); //设置时间
			
        if(0 != iRet)
        {
	       printf("fail to set systemtime.");
        }
    }