Linux-File Management

Common Directory

• / root directory
• /root root user's home directory
• /home/username Ordinary user's home directory
• /etc configuration file directory
• /bin command directory
• /sbin management command directory
• /usr/bin /usr/sbin Other pre-installed directories

Help command

Use the help command to check the usage of a command in detail, linux are many 061d32b9f29b8d commands, and the reasonable use of the help command will help us improve efficiency.

Common help commands are

• man help
• help help
• info help

man help

Before use, you can use the following command to install the Chinese manual of man

yum install -y man-pages-zh-CN

man + digital + file / command you want to view, for example linux which contains both a call passwd files and command, according to the following man help of view, man 1 passwd representatives view passwd help command, and man 4 passwd representatives passwd help file .

1 Commands
          用户可从 shell 运行的命令

2 System calls
          必须由内核完成的功能

3 Library calls
          大多数 libc 函数，例如 qsort(3))

4 Special files
          /dev) 目录中的文件

5 File formats and conventions
          /etc/passwd 等人类可读的文件的格式说明

6 Games

7 Macro packages and conventions
          文件系统标准描述，网络协议，ASCII 和其他字符集，还有你眼前这份文档以及其他东西

8 System management commands
          类似 mount(8) 等命令，大部分只能由 root 执行

9 Kernel routines
          这是废弃的章节。       
          原来曾想把一些关于核心的文件放在这里,但是实际上只有极少数可以写成文件放在这里,而且它们也很快过时了。
          核心开发者可以找到其他更好的资源。

Help

• Internal commands use help help
  For example: help cd
• External commands use help help
  For example: ls --help

What are internal commands and external commands? The commands that come with shell are called internal commands, and the others are external commands.

Use the type + command to check whether it is an internal command. For cd is a shell builtin shows that cd

[root@VM-24-13-centos ~]# type cd
cd is a shell builtin
[root@VM-24-13-centos ~]# type ls
ls is aliased to `ls --color=auto'

Info help

It is help , as a supplement.

File operation commands

ls command

ls displays the files and folders in the current folder

ls + folder directory displays the files and folders in the specified file directory

ls /data /tmp /dev can simultaneously view multiple directories, such as the beginning of the command can be displayed simultaneously data tmp dev following.

ls -l long format display

• The first group is the format and permissions of the - first character 061d32b9f29fad represents the file type, and d represents the folder.
• The second set of data is a number representing how many files there are under this file, 1 means that this is only one file, and if it is not 1, it means that it is a folder.
• The third set of data represents who created the file.
• The fourth group of data represents which user group the user who created this file belongs to.
• The fifth set of data represents the current file size, the unit is byte .
• The sixth set of data represents the last modification time.
• The seventh set of data represents the file name.

-rw-r--r-- 1 root root 14985 12月 27 21:45 404.html
-rw-r--r-- 1 root root   631 12月 27 21:45 apple-touch-icon.png
drwxrwxrwx 6 root root  4096 12月 12 21:10 assets
-rw-r--r-- 1 root root    11 12月 27 21:45 CNAME
-rw-r--r-- 1 root root   631 12月 27 21:45 favicon.ico
-rw-r--r-- 1 root root  7294 12月 27 21:45 index.html
-rw-r--r-- 1 root root  1062 12月 27 21:45 LICENSE
drwxrwxrwx 8 root root  4096 12月 21 00:01 MongoDB文档数据库
drwxrwxrwx 6 root root  4096 12月 27 21:46 netty高性能网络框架
drwxrwxrwx 6 root root  4096 12月 24 09:28 Netty高性能网络框架
-rw-r--r-- 1 root root    77 12月 27 21:46 udownload.bat
-rw-r--r-- 1 root root    66 12月 27 21:46 upload.bat
drwxrwxrwx 4 root root  4096 12月 18 01:20 生活日记

ls -a shows all files, including hidden files.

ls -r displayed in reverse.

ls -t according to the creation time.

For example, the following ls -l -r -t represents reverse sorting according to the creation time, which is equivalent to ls -lrt it is not reversed, it should be the latest modified first.

[root@VM-24-13-centos home.pages]# ls -lrt
总用量 68
drwxrwxrwx 6 root root  4096 12月 12 21:10 assets
drwxrwxrwx 4 root root  4096 12月 18 01:20 生活日记
drwxrwxrwx 8 root root  4096 12月 21 00:01 MongoDB文档数据库
drwxrwxrwx 6 root root  4096 12月 24 09:28 Netty高性能网络框架
-rw-r--r-- 1 root root 14985 12月 27 21:45 404.html
-rw-r--r-- 1 root root   631 12月 27 21:45 apple-touch-icon.png
-rw-r--r-- 1 root root    11 12月 27 21:45 CNAME
-rw-r--r-- 1 root root   631 12月 27 21:45 favicon.ico
-rw-r--r-- 1 root root  7294 12月 27 21:45 index.html
-rw-r--r-- 1 root root  1062 12月 27 21:45 LICENSE
drwxrwxrwx 6 root root  4096 12月 27 21:46 netty高性能网络框架
-rw-r--r-- 1 root root    77 12月 27 21:46 udownload.bat
-rw-r--r-- 1 root root    66 12月 27 21:46 upload.bat

ls -R recursive display

ls -ld View folder information

ls -lh displays the file size in a more friendly way K M G .

mkdir command

mkdir folder name to create a folder.

mikdir -p folder name/...recursively create a folder.

cp command

cp file folder Copy a file to the corresponding folder.

cp -r folder folder Copy the folder to a folder, -r still plays a recursive role.

cp -p The information such as the creation time when the file folder is copied remains unchanged.

cp -a When the file folder is copied, the authority user information will not change.

mv command

mv a b directory unchanged is equivalent to modifying the name.

mv a ../b equivalent to moving a to... and modifying the name to b.

Text view command

cat command

cat file outputs all the contents of the text.

cat -s Converts continuous blank lines into one blank line when outputting the content of the file.

cat -b When outputting text content in a file, add a line number before non-blank lines.

cat -n file output text content all line front home number.

head command

head file output text content from the beginning, the default is 10 lines.

161d32b9f2a3e4 head -n output n lines from the

tail command

tail file outputs text content from the end, 10 lines by default.

tail -n output n lines of text from the end of the file.

tail -f file outputs the file content from the end and tracks real-time text content updates.

tail -fn200 The file outputs 200 lines of text from the end and traces it.

wc command

wc file outputs four information: text lines Number of text words Number of text bytes File name

wc -c file text bytes

wc -w file text word count

wc -l file text line number

wc -L The length of the longest line in the file text

more command

more File to view text content by line

Pack and compress commands

tar command

package

tar cf .../name.tar -C The directory to be packaged Pack a directory into a tar to a certain folder c represents the creation of the f representative file.

compressed

tar zcf .../name.tar.gz -C The directory to be packaged z represents compression, instead of gzip , sometimes tar.gz will also be abbreviated to tgz

tar jcf .../name.tar.bz2 -C The directory to be packaged j represents compression, instead of bzip2 , sometimes tar.bz2 will also be abbreviated to tbz2 , bzip , which takes a longer time to compress the file.

unzip package

tar xf ...tar the packaged file

tar zxf ...tar.gz packaged and compressed gzip file decompression

tar jxf ...tar.bz2 packaged and compressed bz2 file decompression

You can also add the v parameter to view the compression/decompression process after executing the above command