https://www.cnblogs.com/ggjucheng/archive/2013/01/13/2858470.html
http://www.cppblog.com/API/archive/2011/04/24/144895.html
http://blog.chinaunix.net/uid-25324849-id-3079445.html
http://www.itshouce.com.cn/linux/linux-awk.html
http://www.zsythink.net/archives/tag/awk/
原文：https://www.cnblogs.com/carey9420/p/12744812.html