查看命令位置，查找命令

which命令 查看命令的位置

[root@VM-12-15-opencloudos ~]# which cd
/usr/bin/cd
[root@VM-12-15-opencloudos ~]# which java
/usr/local/java/jdk1.8.0_261/bin/java
[root@VM-12-15-opencloudos ~]# which pwd
/usr/bin/pwd

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find查找文件

find 起始路径 -name "被查找的文件名"
被查找的文件名支持*来做模糊查询

find /usr -name "*test*"

find 起始路径 -size +|-n[KMG]
![在这里插入图片描述](https://img-blog.csdnimg.cn/direct/e5133c89d48c48f2bd3044e0f97e3e4f.png

find / -size +1G

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grep命令

grep [-n] 关键字 文件路径
-n可选参数，可以在文件中显示行号

[root@VM-12-15-opencloudos usr]# grep -n 127 /usr/local/nginx/conf/nginx.conf
41:            proxy_pass http://127.0.0.1:8089;
67:	 #       proxy_pass http://127.0.0.1:8089/user;

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wc命令统计文件行数，单词数量等

wc [-c -m -l -w] 文件路径

[root@VM-12-15-opencloudos usr]# wc -cmlw /usr/local/nginx/conf/nginx.conf
 112  210 2318 2496 /usr/local/nginx/conf/nginx.conf

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管道符 |

[root@VM-12-15-opencloudos usr]# cat /usr/local/nginx/conf/nginx.conf | grep 127
            proxy_pass http://127.0.0.1:8089;
	 #       proxy_pass http://127.0.0.1:8089/user;

作用是将左边的结果作为右边的输入
更多示例

[root@VM-12-15-opencloudos usr]# ll -h /usr/bin|grep cd
-rwxr-xr-x. 1 root root    26 Jul 25  2022 cd
lrwxrwxrwx. 1 root root     6 Jul 25  2022 mcd -> mtools

echo 命令

在命令行输出指定内容，可以使用反引号，输出其中的命令的内容

[root@VM-12-15-opencloudos usr]# echo "hello world"
hello world
[root@VM-12-15-opencloudos usr]# echo `pwd`
/usr
[root@VM-12-15-opencloudos usr]# echo `1+1`
-bash: 1+1: command not found

重定向符 > 和 >>

>:将左侧命令的结果，覆盖写入到符号右侧指定的文件中
>>:将左侧命令的结果，追加写入到符号右侧指定的文件中
[root@VM-12-15-opencloudos usr]# ll > text.txt
[root@VM-12-15-opencloudos usr]# cat text.txt
total 140
dr-xr-xr-x.   2 root root 36864 Jan 30 16:43 bin
drwxr-xr-x.   2 root root  4096 Jan 30  2023 config
drwxr-xr-x.   2 root root  4096 May 26  2022 games
drwxr-xr-x.  50 root root  4096 Oct 25 13:38 include
dr-xr-xr-x.  36 root root  4096 Oct 25 13:37 lib
dr-xr-xr-x.  61 root root 45056 Oct 25 13:38 lib64
drwxr-xr-x.  32 root root  4096 Jul  7  2023 libexec
drwxr-xr-x.  27 root root  4096 Oct 25 15:28 local
dr-xr-xr-x.   2 root root 20480 Mar 18 17:49 sbin
drwxr-xr-x. 116 root root  4096 Jul  7  2023 share
drwxr-xr-x.   5 root root  4096 Jan 30  2023 src
-rw-r--r--    1 root root     0 Mar 31 14:36 text.txt
lrwxrwxrwx.   1 root root    10 May 26  2022 tmp -> ../var/tmp

tail命令

查看文件尾部内容，跟踪文件的最新修改
tail [-f -num] linux路径