grep 同时满足多个关键字和满足任意关键字
① grep -E "word1|word2|word3" file.txt
满足任意条件(word1、word2和word3之一)将匹配。
② grep word1 file.txt | grep word2 |grep word3
必须同时满足三个条件(word1、word2和word3)才匹配。
② ls -A | grep 'file1 | file2 | file3'
必须同时满足三个条件(word1、word2和word3)才匹配。
![](https://images2017.cnblogs.com/blog/900887/201711/900887-20171107153316591-1561003445.png)