Mastering the basic Linux commands can speed up the use of the process, mainly including four categories: file and directory operations, viewing and editing file content, system information and process management, and permissions and users related. 1. File and directory operation commands include ls to view the directory contents, cd to switch the directory, pwd to display the current path, mkdir to create the directory, rm/rmdir to delete the file or directory, cp/mv to copy and move or rename the file. 2. To view and edit file content, you can use cat to output small file content, less pagination to view large files, head/tail to view the beginning or end of the file, nano/vim to edit the file, and echo to write strings to the file. 3. The system information and process management commands have top/htop to view resources, ps to find the process, kill/killall to end the process, df/du to view disk space, and free to view memory usage. 4. Permissions related to user commands such as chmod modify permissions, chown changes the user group to which it belongs, su/sudo switches the user, and whoami/id checks user information. Beginners can check while using it and gradually become familiar with these commonly used commands.

When you are new to Linux, mastering some basic commands can help you get started faster. These commands can not only help you check the system status, but also complete daily file operations and permission management.

File and directory operations: the most commonly used basic commands

This part of the command is used every day, especially when you troubleshoot problems on the server or deploy applications.

• ls : List the directory contents, add the -l parameter to see detailed information (such as permissions, size, modification time, etc.).
• cd : Switch the directory, such as cd /home/user to enter the specified path.
• pwd : Shows the full path to the current directory.
• mkdir : Create a new directory, add -p to create multi-layer directories recursively.
• rm and rmdir : delete files or empty directories, rm -r can recursively delete non-empty directories.
• cp and mv : copy and move files, mv can also be used to rename them.

It is recommended that beginners be familiar with the basic usage of these commands first, and then gradually try operations with parameters.

Viewing and editing file content: Several practical methods

Sometimes you need to quickly view the contents of a file, or make simple edits. Here are some common ways:

• cat : output file content to the terminal, suitable for small files.
• less : View content on pages, suitable for large files, press q to exit.
• head and tail : View the beginning and end of the file respectively, and display 10 lines by default.
• nano or vim : These two are commonly used text editors. It is easier to get started with nano , vim is more powerful but has a steep learning curve.
• echo : You can write strings to a file, such as echo "hello" > file.txt .

Note: It is best to back up a copy of the original file before editing the configuration file to avoid misoperation caused by service exceptions.

System information and process management: Understand the running status

When you want to see how the machine runs, or if a program gets stuck, these commands come in handy:

• top or htop : Check the system resource usage in real time, htop is more intuitive.
• ps : Check the currently running process, and it works better with grep , such as ps aux | grep nginx .
• kill and killall : end the process, kill PID is to send a termination signal, kill -9 PID is to force termination.
• df and du : View disk space, df -h display is easier to read.
• free : Check memory usage, add -h parameter to better readability.

If you are operating on a remote server, remember not to kill the system key processes casually.

Permissions are related to users: secure operations cannot be ignored

Linux's permission mechanism is relatively strict, and understanding basic permission settings can avoid many problems:

• chmod : Modify file permissions, such as chmod 755 script.sh is set to executable.
• chown : Modify the user and group to which the file belongs, such as chown user:group file.txt .
• su and sudo : Switch users or temporarily execute commands as administrators.
• whoami and id : View current user information.

Unreasonable permission settings may cause the script to be unable to run or the website to be accessed, so remember to test whether the function is normal after modifying the permissions.

Basically that's it. When you first learn, you don’t need to remember them all. Use them while checking them. After you become proficient, you will find that these commands are actually not complicated, but very practical.

The above is the detailed content of What are the basic Linux commands every beginner must know?. For more information, please follow other related articles on the PHP Chinese website!