boost获取系统时间(毫秒级)

在c++的chrono中没有找到相应的实现，只好从boost里面找了，代码如下：

#include<boost/date_time/posix_time/posix_time.hpp>

// Get current time from the clock, using microseconds resolution
const boost::posix_time::ptime now = boost::posix_time::microsec_clock::local_time();
// Get the time offset in current day
const boost::posix_time::time_duration td = now.time_of_day();
frame.h = td.hours();
frame.m = td.minutes();
frame.s = td.seconds();
frame.ms = td.total_milliseconds() - ((frame.h * 3600 + frame.m * 60 + frame.s) * 1000);