Common Linux commands (the most detailed and complete command summary)

introduce

Linux is an open source operating system widely used in servers and personal computers. This document will introduce some commonly used Linux commands to help users better understand and use the Linux system.

Table of contents

1. File and directory operations
2. View and edit file content
3. Process management
4. System Management
5. network management

File and directory operations

ls

Command format:ls [选项] [文件或目录]

Function: Display directory content or file information.

Options:

• -l: Display file details in long format.
• -a: Show all files including hidden files.
• -h: Display the file size in human-readable form.
• -R: Display directory and subdirectory contents recursively.

Example:

$ ls -l
$ ls -a
$ ls -lh
$ ls -R

cd

Command format:cd [目录]

Function: Switch the current working directory.

Example:

$ cd /path/to/directory
$ cd ..
$ cd ~

pwd

Command format:pwd

Function: Display the absolute path of the current working directory.

Example:

$ pwd

mkdir

Command format:mkdir [选项] 目录

Function: Create directory.

Options:

• -p: Create directories recursively. If the upper-level directory does not exist, it will also be created.

Example:

$ mkdir mydir
$ mkdir -p /path/to/directory

cp

Command format:cp [选项] 源文件 目标文件

Function: Copy files or directories.

Options:

• -r: Copies a directory and its contents recursively.

Example:

$ cp file1.txt file2.txt
$ cp -r dir1 dir2

mv

Command format:mv [选项] 源文件 目标文件

Function: Move files or directories, or rename files or directories.

Options:

• -i: If the target file already exists, prompt the user whether to overwrite it.

Example:

$ mv file1.txt newdir/file1.txt
$ mv file1.txt file2.txt

rm

Command format:rm [选项] 文件或目录

Function: Delete files or directories.

Options:

• -r:Recursively delete a directory and its contents.
• -f: Forced deletion without prompting the user for confirmation.

Example:

$ rm file1.txt
$ rm -r dir1
$ rm -rf dir1

find

Command format:find [路径] [选项]

Function: Search for files under the specified path.

Options:

• -name: Search by file name match.
• -type: Search by file type match

View and edit file content

cat

Command format:cat [选项] 文件

Function: Display file content.

Options:

• -n: Display line number.

Example:

$ cat file.txt
$ cat -n file.txt

less

Command format:less [选项] 文件

Function: Display file contents in pages.

Options:

• -N: Display line number.
• 空格键: Page down.
• b: Page up.
• /关键词: Search for keywords in files.

Example:

$ less file.txt
$ less -N file.txt

head

Command format:head [选项] 文件

Function: Display the content at the beginning of the file.

Options:

• -n: Specify the number of display lines, the default is 10 lines.

Example:

$ head file.txt
$ head -n 5 file.txt

tail

Command format:tail [选项] 文件

Function: Display the content at the end of the file.

Options:

• -n: Specify the number of display lines, the default is 10 lines.
• -f: Track file content changes in real time.

Example:

$ tail file.txt
$ tail -n 5 file.txt
$ tail -f file.txt

grip

Command format:grep [选项] 模式 文件

Function: Search for the specified pattern in the file.

Options:

• -i: Ignore case.
• -v: Reverse match, display unmatched lines.

Example:

$ grep "pattern" file.txt
$ grep -i "pattern" file.txt
$ grep -v "pattern" file.txt

we

Command format:vi 文件

Function: Use Vi editor to open files.

Vi is one of the most commonly used text editors in Linux, with powerful editing and search capabilities.

Example:

$ vi file.txt

In the Vi editor you can use the following commands:

• i: Enter insert mode and you can edit the file.
• Esc: Exit insert mode.
• :w:save document.
• :q: Exit Vi editor.
• :wq: Save the file and exit the Vi editor.

Process management

ps

Command format:ps [选项]

Function: Display currently running processes.

Options:

• -f: Show detailed information.
• -aux: Show all processes.

Example:

$ ps
$ ps -f
$ ps -aux

top

Command format:top

Function: Display system process status in real time.

The Top command sorts processes by indicators such as CPU usage and memory usage, and updates them dynamically.

Example:

$ top

In the Top interface, you can use the following commands:

• q: Exit Top.

kill

Command format:kill [选项] 进程ID

Function: Terminate the specified process.

Options:

• -9: Forcefully terminate the process.

Example:

<br/>

```powershell
$ kill 1234
$ kill -9 5678

pstree

Command format:pstree [选项]

Function: Display the relationship between processes in a tree structure.

Options:

• -p: Display process ID.

Example:

$ pstree
$ pstree -p

System Management

uname

Command format:uname [选项]

Function: Display system information.

Options:

• -a: Display all information.

Example:

$ uname
$ uname -a

df

Command format:df [选项] [文件或目录]

Function: Display disk space usage.

Options:

• -h: Display the file size in human-readable form.
• -i: Display inode information.

Example:

$ df
$ df -h
$ df -i

of

Command format:du [选项] [文件或目录]

Function: Display the disk usage of a file or directory.

Options:

• -h: Display the file size in human-readable form.
• -s: Show only the total size.

Example:

$ du
$ du -h
$ du -s

free

Command format:free [选项]

Function: Display system memory usage.

Options:

• -h: Display the file size in human-readable form.

Example:

$ free
$ free -h

ifconfig

Command format:ifconfig [网络接口] [选项]

Function: Display or configure network interface information.

Options:

• -a: Display all network interfaces.
• 网络接口:Specify the network interface to be displayed or configured.

Example:

$ ifconfig
$ ifconfig eth0

ping

Command format:ping [选项] 主机名或IP地址

Function: Test the connectivity with the specified host.

Options:

• -c: Send the specified number of ICMP requests.
• -i: Specify the time interval for ICMP requests.

Example:

$ ping google.com
$ ping -c 5 google.com
$ ping -i 2 google.com

network management

wget

Command format:wget [选项] URL

Function: Download files from the specified URL.

Options:

• -O: Specify the saving path and file name of the downloaded file.

Example:

$ wget http://example.com/file.txt
$ wget -O /path/to/save/file.txt http://example.com/file.txt

curl

Command format:curl [选项] URL

Function: Data transfer via URL.

Options:

• -o: Specify the saving path and file name of the downloaded file.

Example:

$ curl http://example.com/file.txt
$ curl -o /path/to/save/file.txt http://example.com/file.txt

ssh

Command format:ssh [选项] 用户名@主机名或IP地址

Function: Log in to the remote host through SSH protocol.

Options:

• -p: Specify the port number of the SSH server.

  Example:

  $ ssh username@hostname
  $ ssh -p 2222 username@hostname
  

  scp

  Command format:scp [选项] 源文件 目标文件

  Function: Copy files between local host and remote host through SSH protocol.

  Options:

  • -P: Specify the port number of the SSH server.

  Example:

  $ scp file.txt username@hostname:/path/to/destination/
  $ scp -P 2222 file.txt username@hostname:/path/to/destination/
  

  ifup

  Command format:ifup 网络接口

  Function: Start the specified network interface.

  Example:

  $ ifup eth0
  

  ifdown

  Command format:ifdown 网络接口

  Function: Close the specified network interface.

  Example:

  $ ifdown eth0
  

  iptables

  Command format:iptables [选项] 规则

  Function: Configure Linux firewall rules.

  Options:

  • -A: Add rules.
  • -D: Delete rule.
  • -L: List rules.

  Example:

  $ iptables -A INPUT -p tcp --dport 80 -j ACCEPT
  $ iptables -D INPUT -p tcp --dport 80 -j ACCEPT
  $ iptables -L
  

  The above are some commonly used Linux commands, covering file and directory operations, file content viewing and editing, process management, system management and network management. By mastering these commands, you can better manage and operate your Linux system. Hope this document is helpful to you!