grep笔记

grep用法：

定义：用于文本查找

#从file中查找带有‘keyword’关键字的行
$ grep keyword file
└─$ grep L unicom.sh 
echo "Hello from LG, thanks for testing.

#从多个文件中查找关键字
$ grep keyword file1 file2 file3
└─$ grep -l for  unicom.sh
unicom.sh

#递归查找目标文件夹中所有目标信息的文件，并可实现精确过滤
$ grep -r for ./file    
./file/unicom.sh:echo "Hello from LG, thanks for testing.
                                                                                      
$ grep -r for ./file | grep DEVICE
                                                                                       
$ grep -r for ./file | grep sh    
./file/unicom.sh:echo "Hello from LG, thanks for testing.

#加入 -v 参数，反转grep匹配
$ grep -v keyword file