一个好用的C++日志产生类，不但好用，而且它也很老，好像是老外写的，虽然这么多年了，但还是有很多人在用这个日志类。 -One-to-use C++ log generated category, not only easy to use, and it is also very old, I think it was written by a foreigner, even though so many years, but there are still many people log i