# 18.正则表达式

> *...the intellectual activity associated with software development is largely one of gaining insight.* *--Stowe Boyd*

目录

* [18.1 正则表达式简介](http://tldp.org/LDP/abs/html/x17129.html)  
* [18.2 文件名替换](http://tldp.org/LDP/abs/html/globbingref.html)  

为了充分利用shell脚本，您需要熟练掌握正则表达式。有一些在脚本中常用的特定的命令和工具，例如grep、expr、sed和awk，这些命令会解释和使用正则表达式。版本三的bash实现了它独特的正则匹配符：=\~。


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