Skip to main content

Introduction Linux Command Line

This document serves as a foundational guide for users unfamiliar with the Linux operating system, particularly those transitioning from Windows environments. Created with the assistance of an advanced AI Language Model, it offers detailed explanations and instructions on essential Linux tasks. Topics covered include file navigation, manipulation, permissions, user roles, and the specific differences between regular and root users.

Understanding the Working Directory​

In Linux, when you are working in the terminal, you are always inside a specific directory. This directory is called the “working” or “current” directory.

Finding Your Current Directory​

Use the pwd command to find out which directory you’re in.

pwd

Listing the Contents of the Current Directory​

The ls command helps you see what’s inside your current directory.

ls

You can move to another directory using the cd command.

cd /path/to/directory

Putting It All Together: An Example​

Imagine you want to find a game’s configuration file in the directory /home/user/games/config. Here’s how you might do it:

  • Find out where you are: Use pwd to see your current directory.
  • See what’s around you: Use ls to list the files and directories.
  • Navigate to the directory: Use cd to move into the directory where the file is located.
  • Find the file: Once you’re in the right directory, use ls again to see the file you’re looking for.

Additional Tips for Windows Users​

  • In Windows, paths are written with backslashes (\\), but in Linux, you use forward slashes (/).
  • Linux is case-sensitive, so File.txt and file.txt are different files.

Hidden Files and Directories in Linux​

In Linux, files and directories that are prefixed with a dot (.) are considered “hidden.”

Identifying Hidden Files and Directories​

Use ls -a to view all files, including hidden ones, in your current directory.

Finding Hidden Files and Directories​

Use the find command to find hidden files or directories within a specific path.

find ~/ -name ".*"

Working with Hidden Files and Directories​

Once you’re inside a hidden directory, you can work with the files and subdirectories just like any other directory.

Moving and Renaming Files​

In Linux, the mv command is used both for moving files from one location to another and for renaming files.

Moving a File​

mv /path/to/source /path/to/destination

Renaming a File​

mv oldfilename newfilename

Creating Directories​

Creating new directories (folders) is done with the mkdir command.

mkdir /path/to/newdirectory

Deleting Files and Directories​

Deleting a File​

rm /path/to/file

Deleting a Directory​

rm -r /path/to/directory

Introduction to nano​

nano is a command-line text editor that’s often included by default in many Linux distributions.

Opening and Editing Files with nano​

nano /path/to/file

Saving Changes​

Press Ctrl + O (that’s the letter “O,” not a zero), then Enter to save the changes.

Finding Files by Name or Extension​

Use the find command to find a file by name or extension.

find / -name filename.txt

Understanding File Permissions​

In Linux, every file and directory has a set of permissions that define who can read, write, and execute it.

Viewing Permissions​

ls -l /path/to/file

Changing Between Users and Understanding root​

Regular Users vs. root​

  • Regular Users: Restricted from making system-wide changes.
  • Root User: Full control over the system.

Switching Users​

su - username

Why Not to Use chmod 777​

Using chmod 777 sets the permissions to allow anyone to read, write, and execute the file.

Summary​

Understanding how to find files and navigate file permissions is crucial for managing a Linux system. Care should be taken with administrative powers, and broad permission changes like chmod 777 should be avoided due to the significant risks involved.

Please note that I've condensed the content into a markdown format, preserving the structure and essential information. If you need further adjustments or specific sections, please let me know!