grep: Global search REgular expression and Print out the line
作用： 文本搜素工具，根据用户指定的“模式”对目标文本逐行进行匹配检查；打印匹配到的行模式： 由正则表达式字符及文本字符所编写的过滤条件。
格式选项grep [options] pattern [FILE...]-color=auto对匹配到的文本着色显示-v显示不被pattern匹配到的行-i忽略字符大小写-n显示匹配到的行号-o仅显示匹配到的字符串-A #after,后#行-B#before，前#行-C#context，前后各#行-e实现多个选项间的逻辑or关系，如： grep -e 'cat' -e 'dog' file-w匹配整个单词-E使用ERE，相当于egrep-F不支持正则表达式，相当于fgrep-r递归目录，但不处理软连接-R递归目录，但处理软连接示例
[root@C17-17 ~]#alias grepalias grep='grep --color=auto'[root@C17-17 ~]#grep 17 1.txtC17-1710.0.0.17[root@C17-17 ~]#grep 17 1.txtC17-1710.0.0.17[root@C17-17 ~]#grep label 1.txtlabels:[root@C17-17 ~]#grep label 1.txtlabels:[root@C17-17 ~]#[root@C17-17 ~]#ls1.txt 2.txt redis.yaml[root@C17-17 ~]#'grep' label 1.txtlabels:[root@C17-17 ~]#"grep" label 1.txtlabels:[root@C17-17 ~]#[root@C17-17 ~]#ls1.txt 2.txt redis.yaml[root@C17-17 ~]#cat 1.txtC17-1710.0.0.1710.0.0.1910.0.0.18Sun Oct 22 21:35:43 CST 2023name: publish-redislabels: app.kubernetes.io/instance: ops app.kubernetes.io/name: publish-redis[root@C17-17 ~]#grep publish 1.txtname: publish-redis app.kubernetes.io/name: publish-redis[root@C17-17 ~]#alias grepalias grep='grep --color=auto'[root@C17-17 ~]#grep publish 1.txtname: publish-redis app.kubernetes.io/name: publish-redis[root@C17-17 ~]#grep -v '10' 1.txtC17-17Sun Oct 22 21:35:43 CST 2023name: publish-redislabels: app.kubernetes.io/instance: ops app.kubernetes.io/name: publish-redis[root@C17-17 ~]#grep Sun 1.txtSun Oct 22 21:35:43 CST 2023[root@C17-17 ~]#grep sun 1.txt[root@C17-17 ~]#grep -i sun 1.txtSun Oct 22 21:35:43 CST 2023[root@C17-17 ~]#grep -in sun 1.txt8:Sun Oct 22 21:35:43 CST 2023[root@C17-17 ~]#grep -io sun 1.txtSun[root@C17-17 ~]#grep -A 2 labels 1.txtlabels: app.kubernetes.io/instance: ops app.kubernetes.io/name: publish-redis[root@C17-17 ~]#grep -B 3 labels 1.txtSun Oct 22 21:35:43 CST 2023name: publish-redislabels:[root@C17-17 ~]#grep -C 3 labels 1.txtSun Oct 22 21:35:43 CST 2023name: publish-redislabels: app.kubernetes.io/instance: ops app.kubernetes.io/name: publish-redis[root@C17-17 ~]#grep -e 'Sun' -e 'labels' 1.txtSun Oct 22 21:35:43 CST 2023labels:[root@C17-17 ~]#grep -E 'Sun|labels' 1.txtSun Oct 22 21:35:43 CST 2023labels:[root@C17-17 ~]#egrep 'Sun|labels' 1.txtSun Oct 22 21:35:43 CST 2023labels:[root@C17-17 ~]#grep -w labels 1.txtlabels:[root@C17-17 ~]#grep -r publish-redis ././redis.yaml: name: publish-redis./redis.yaml: app.kubernetes.io/name: publish-redis./redis.yaml: app.kubernetes.io/name: publish-redis./redis.yaml: app.kubernetes.io/name: publish-redis./redis.yaml: name: publish-redis./redis.yaml: name: publish-redis./redis.yaml: app.kubernetes.io/name: publish-redis./redis.yaml: app.kubernetes.io/name: publish-redis./1.txt:name: publish-redis./1.txt: app.kubernetes.io/name: publish-redis./.viminfo: app.kubernetes.io/name: publish-redis
