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Linux Navigation and File Management

Linux Navigation and File Management
Anees Asghar
Technical writer
Linux
27.01.2025
Reading time: 7 min

Navigating and manipulating files in Linux is a core concept for fluently operating the system. The terminal acts as your powerful control center, allowing you to traverse through directories, fetch files, and perform modifications. Whether you work on a local Linux installation or access a remote system via a secured SSH session, you can rely on basic commands to streamline your tasks. 

This tutorial will use practical examples and precise instructions to demonstrate Linux file navigation and manipulation.

Exploring Linux File Setup

Linux structures its files and directories in a hierarchical layout resembling a tree, where the root directory (/) serves as the foundation. Everything, including folders and files, branches out from this root. Below is a concise synopsis of some key directories:

Root (/)

It is the main folder where everything begins. Every other directory and file is kept inside it.

/home

This folder contains personal files for every user. For instance, if your username is hostman, files will be kept in /home/hostman.

/var

This folder keeps frequently updated files, including system logs and temporary data. Logs can be located in /var/log.

/etc

Linux preserves configuration files and system settings, including networking and account setup inside the etc directory.

File Navigation and Manipulation in Linux

Navigating and organizing files involves traversing the file system to handle files and directories. Linux commands make these tasks efficient, let you automate them, and provide you precise control, especially in non-graphical environments.

Checking Current Directory

The pwd command retrieves your current address in the file system. It's useful for identifying your position when navigating through complex directory structures:

pwd

The outcome indicates that the active directory is anees located inside the system’s home directory:

Image1

Traversing Directories

The cd utility lets us traverse distinct directories. Entering the command below will take us to the root directory:

cd /

Image3

Let’s employ cd with the tilde symbol ~ or cd without any option to traverse back to the Home Directory:

cd ~

Image2

Execute cd with the - sign to toggle between current and previous directories:

cd -

It switches us from hostmanExamples to the previous folder, i.e., hostman:

Image5

Similarly, running cd with a precise path lets us access a particular file/directory:

cd Desktop/hostman/hostmanExamples

Image4

Retrieving Directories Data

ls is a Linux utility that retrieves the folder’s data, such as files, links, and sub-folders. You can utilize distinct flags with ls to exhibit additional details like access rights, sizes, and last modified timestamps.

Let’s utilize ls without any flag to retrieve the folder’s data from the recent path:

ls

Image7

Utilizing ls with a precise path retrieves the details of that directory:

ls Desktop/hostman/

Image6

To get invisible files, utilize ls with -a flag:

ls -a

048abd61 B1ef 4d04 804e 7215ad04aa02

To demonstrate precise information, run ls followed by the -l flag:

ls -l

Image8

Returning Folder Structure

The tree command retrieves folders and files in a hierarchical tree format. To do that, utilize the syntax:

tree /directory_path

Let’s retrieve the directory structure in a tree format, with each file’s size depicted in a human-understandable structure:

tree -h

Image15

Hidden Linux Files

These files or folders initiate with a dot (.) and are invisible by default. They typically keep configuration settings or important data for applications, such as .bashrc for customizing terminal behavior or .ssh for managing secure keys. They can be viewed by utilizing the ls -a command or by enabling the "show hidden files" from the file managers. 

File Administration

Let’s study the below-listed Linux sections to handle files and directories effortlessly.

File Creation

Files are made in Linux via the touch command. It offers a simple method to make blank files. If the file is already present, touch revises the DateTime of the last change instead of generating a new file:

touch hostmanExample.txt

Image11

Folder Creation

The mkdir utility in Linux allows you to create a directory at the desired path:

mkdir hostmanFolder

It constructs a hostmanFolder in the current directory:

Image13

Re-labeling and Relocating Files

mv lets you alter the name of files or transfer them to a distinct location. To re-title a file, write the existing name followed by the desired one:

mv hostmanExample.txt hostman1.txt

This alters the name of hostmanExample.txt to hostman1.txt:

Image16

Likewise, users can transfer a file by specifying its name and the destination directory:

mv hostman1.txt /hostmanFolder

Image17

Cloning Files/Directories

To duplicate a file/folder, execute cp with the source file and the destination path:

cp graphqlFile.txt hostmanFolder

Image18

To duplicate a directory along with its contents, employ the -r (recursive) flag with cp:

cp -r graphql-examples hostmanFolder

It clones the complete graphql-examples folder with all its data to the hostmanFolder:

Image19

Deleting Files and Directories

The rm command removes files and directories eternally without sending them to the bin/trash, so use it cautiously by providing the file name:

rm graphqlFile.txt

Image20

Likewise, to trash a directory and all of its data, employ the -r flag:

rm -r hostmanFolder

Image21

For extended safety, utilize the -i flag, which asks for verification before deleting any item:

rm -ri graphql-examples

Specify y (for "yes") and press Enter to approve the removal of each file or directory. If you input n, the file or directory will not be deleted.

File Compression

Zipping files is vital for sharing data, and organizing files and storage space. To accomplish this, Linux utilizes tools like gzip and bzip2

gzip is a widely employed tool for compressing files. It decreases the file size while retaining the original data. Let’s employ gzip to compress the hostmanExample.txt file:

gzip hostmanExample.txt

The command compresses the original file (overrides the actual file):

Image22

Similarly, users can execute gzip with -d flag to decompress a compressed file:

gzip -d hostmanExample.txt.gz

Image23

Users can employ the -k flag to compress a file without overriding the original one:

gzip -k hostmanExample.txt

Image9

File Archiving

File archiving refers to the method of grouping multiple files and directories together into one unified archive file. This practice makes it easier to share, compress, and manage large data by consolidating various items into a single, organized package. For this purpose, we can utilize the tar command:

tar -cvf hostman.tar hostmanExample.txt hostman1.txt hostmanDir/

By default, it makes an archive without compression, which contains hostmanExample.txt and hostman1.txt files and a hostmanDir directory:

Image12

To assemble a compressed archive, we can define the compression format such as z for gzip and j for bzip2:

tar -czvf hostman1.tar.gz hostmanExample.txt hostman1.txt hostmanDir/

Image14

Similarly, users can extract the archived data by executing the tar command with the -x flag:

tar -xvf hostman.tar

To extract a gzip or bzip2-compressed archives, use the -z or -j flags respectively:

tar -xzvf hostman1.tar.gz

Navigating with Shortkeys

Shortcut keys can save time and make command-line navigation more efficient:

  • Use cd - to switch to the previous directory.
  • Run cd .. to steer one directory up.
  • Execute cd ~ to return to the home folder.
  • Press Ctrl + A to leap to the left-most (beginning) of the command line.
  • Press Ctrl + E to leap to the right-most (end) of the command line.
  • Hit Tab to auto-complete file or folder names.

Gaining proficiency in these fundamental shortcut keys will simplify and enhance your experience with Linux file management.

Conclusion

In this write-up, we wrapped the essential techniques for navigating and handling files in Linux. We examined how to switch between directories and depict their data. We also examined the creation, deletion, renaming, and relocation of files and directories. Additionally, we explored invisible files, their functionality, and methods to handle them. Mastering these core skills will make working with Linux more easily and effectively.

Linux
27.01.2025
Reading time: 7 min

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When finished, verify it with the following command: fdisk -l In the output, you will see that the installation image has been written to the new disk, creating two necessary partitions. Step 4. After writing the installation image, proceed to boot from it. To do this, go to the Access tab and boot the server from the recovery disk. Open the console in the control panel.  Step 5. In the console window, go to the Boot existing OS menu item and press Tab on your keyboard. This will allow you to edit the text at the bottom of the screen. Here, you need to manually replace hd0 with hd1, as shown in the figure below. After that, press Enter to launch the installation program. Step 6. In the system bootloader that appears, select the first option. 2. Partitioning the Disk Now we can partition the main disk (sda). 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01 July 2025 · 7 min to read
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NATS Installation, Configuration, and Usage Guide

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Downloading NATS Package Updates Before installation, it's recommended to update the list of available repositories in the system: sudo apt update Downloading the Archive Next, you need to manually download the ZIP archive with NATS from its official GitHub repository: wget https://github.com/nats-io/nats-server/releases/download/v2.10.22/nats-server-v2.10.22-linux-amd64.zip After the download is complete, you can check the file list: ls Among them will be the NATS archive: nats-server-v2.10.22-linux-amd64.zip  resize.log  snap Extracting the Archive Next, install the package that performs ZIP archive extraction: sudo apt install unzip -y The -y flag is added so that the installer automatically answers 'yes' to all questions. Now extract the NATS archive using the installed extractor: unzip nats-server-v2.10.22-linux-amd64.zip Check the file list: ls As you can see, a new folder with the archive contents has appeared: nats-server-v2.10.22-linux-amd64  nats-server-v2.10.22-linux-amd64.zip  resize.log  snap We no longer need the archive, so delete it: rm nats-server-v2.10.22-linux-amd64.zip Installing NATS Server Installation Let's look at the contents of the created folder: ls nats-server-v2.10.22-linux-amd64 Inside it is the main directory with the NATS server: LICENSE  nats-server  README.md This is what we need to copy to the system catalog with binary files: sudo mv nats-server-v2.10.22-linux-amd64/nats-server /usr/local/bin/ After copying, you need to set the appropriate access permissions: sudo chmod +x /usr/local/bin/nats-server The folder with NATS contents, like the archive, can now also be deleted: rm nats-server-v2.10.22-linux-amd64 -R Server Verification Let's verify that the NATS server is installed by requesting its version: nats-server -v A similar output should appear in the console terminal: nats-server: v2.10.22 However, this command doesn't start the server; it only returns its version. You can start the server as follows: nats-server [3704] 2024/11/07 02:59:53.908362 [INF] Starting nats-server [3704] 2024/11/07 02:59:53.908623 [INF] Version: 2.10.22 [3704] 2024/11/07 02:59:53.908669 [INF] Git: [240e9a4] [3704] 2024/11/07 02:59:53.908701 [INF] Name: NC253DIPURNIY4HUXYQYC5LLAFA6UZEBKUIWTBLLPSMICFH3E2FMSXB7 [3704] 2024/11/07 02:59:53.908725 [INF] ID: NC253DIPURNIY4HUXYQYC5LLAFA6UZEBKUIWTBLLPSMICFH3E2FMSXB7 [3704] 2024/11/07 02:59:53.909430 [INF] Listening for client connections on 0.0.0.0:4222 [3704] 2024/11/07 02:59:53.909679 [INF] Server is ready In this case, the server starts with binding to the console terminal, not as a background service. Therefore, to return to command input mode, you need to press Ctrl + C. 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In this case, when exiting the console, the server will stop working. To prevent this, you need to create a file for the systemd service: sudo nano /etc/systemd/system/nats-server.service Its contents will be: [Unit] Description=NATS message broker server After=syslog.target network.target [Service] Type=simple ExecStart=/usr/local/bin/nats-server -c /etc/nats/nats-server.conf User=nats Group=nats LimitNOFILE=65536 ExecReload=/bin/kill -HUP $MAINPID Restart=on-failure [Install] WantedBy=multi-user.target This file contains several key parameters: Description: Short description of the service ExecStart: NATS server startup command with the configuration file explicitly specified User: Name of the user created for NATS Now we need to set up the service to start up at boot:  systemctl enable nats-server --now The --now flag immediately starts the specified service. The corresponding message will appear in the console: Created symlink /etc/systemd/system/multi-user.target.wants/nats-server.service → /etc/systemd/system/nats-server.service. Now check the status of the running service: systemctl status nats-server If the NATS server service started successfully, the corresponding message will be among the console output: ... Active: active (running) ... Connecting to NATS You can connect to the NATS server through the console terminal and thus perform message broker testing. For example, publish messages or subscribe to subjects. Client Installation To manage the NATS server, you need to install the natscli client. You can download it from the official GitHub repository: wget https://github.com/nats-io/natscli/releases/download/v0.1.5/nats-0.1.5-amd64.deb After this, the downloaded archive can be extracted and installed: dpkg -i nats-0.1.5-amd64.deb The archive itself can be deleted as it's no longer needed: rm nats-0.1.5-amd64.deb Sending Messages Now you can send a message to the message broker: nats pub -s 127.0.0.1 "someSubject" "Some message" In this command, we send the message "Some message" to the subject "someSubject" to the message broker running on IP address 127.0.0.1 and located on the standard NATS port - 4222. After this, information about the sent data will appear in the console terminal: 10:59:51 Published 12 bytes to "someSubject" Reading Messages Currently, no one will see this message since there's no agent subscribed to the specified subject. We can simulate a service subscribed to the subject and reading messages using another SSH session. To do this, you need to open another console terminal, connect to the remote machine, and subscribe to the previously specified subject: nats sub -s 127.0.0.1 "someSubject" A message about successful subscription will appear in the terminal: 11:11:10 Subscribing on someSubject Now repeat sending the message from the first terminal: nats pub -s 127.0.0.1 "someSubject" "Some message" Information about the new message will appear in the second terminal: [#1] Received on "someSubject" Some message Let's send another message from the first terminal: nats pub -s 127.0.0.1 "someSubject" "Some message again" The corresponding notification will appear in the second terminal: [#2] Received on "someSubject" Some message again Note that the console output of received messages has numbering in square brackets. Go Program + NATS Let's create a small program in the Golang programming language using the NATS message broker. Installing Go First, you need to ensure that the Go compiler is installed in the system: go version If the following message appears in the console terminal, then Go is not yet installed: Command 'go' not found, but can be installed with: snap install go # version 1.23.2, or apt install golang-go # version 2:1.18~0ubuntu2 apt install gccgo-go # version 2:1.18~0ubuntu2 See 'snap info go' for additional versions. In this case, you need to download it as an archive from the official website: wget https://go.dev/dl/go1.23.3.linux-amd64.tar.gz -O go.tar.gz And then extracted: sudo tar -xzvf go.tar.gz -C /usr/local As we no longer need the downloaded archive, we can delete it: rm go.tar.gz Next, you need to add the Go compiler to the PATH variable so it can be called from the console terminal: echo export PATH=$HOME/go/bin:/usr/local/go/bin:$PATH >> ~/.profile Then apply the changes: source ~/.profile Verify that Go is installed successfully by requesting its version: go version You will see a similar output: go version go1.23.3 linux/amd64 Creating a Project Let's create a separate folder for the Golang program: mkdir nats_go Then navigate to it: cd nats_go And initialize the Go project: go mod init nats_go Installing the Module After project initialization, you need to install the NATS client from the official GitHub repository. You don't need to download anything manually; it's enough to use the built-in Golang function: go get github.com/nats-io/nats.go/ Writing Code Now you can create a file with the program code: nano nats_go.go Its contents will be: package main import ( "fmt" // module for working with console "os" // module for working with system functions "time" // module for working with time "github.com/nats-io/nats.go" // module for working with NATS server ) func main() { // get NATS server address from environment variable url := os.Getenv("NATS_URL") // if there's no address in environment variable, use default address if url == "" { url = nats.DefaultURL } // connect to NATS server nc, _ := nats.Connect(url) // defer message broker cleanup until main() function completion defer nc.Drain() // send message to subject without subscribers to ensure it disappears nc.Publish("people.philosophers", []byte("Hello, Socrates!")) // subscribe to all sub-subjects in "people" subject sub, _ := nc.SubscribeSync("people.*") // extract message msg, _ := sub.NextMsg(10 * time.Millisecond) // output message status (it's not there because it was sent before subscribing to subjects) fmt.Printf("No message? Answer: %v\n", msg == nil) // send message to "philosophers" sub-subject of "people" subject nc.Publish("people.philosophers", []byte("Hello, Socrates!")) // send message to "physicists" sub-subject of "people" subject nc.Publish("people.physicists", []byte("Hello, Feynman!")) // extract message and output to console msg, _ = sub.NextMsg(10 * time.Millisecond) fmt.Printf("Message: %q in subject %q\n", string(msg.Data), msg.Subject) // extract message and output to console msg, _ = sub.NextMsg(10 * time.Millisecond) fmt.Printf("Message: %q in subject %q\n", string(msg.Data), msg.Subject) // send message to "biologists" sub-subject of "people" subject nc.Publish("people.biologists", []byte("Hello, Darwin!")) // extract message and output to console msg, _ = sub.NextMsg(10 * time.Millisecond) fmt.Printf("Message: %q in subject %q\n", string(msg.Data), msg.Subject) } Now you can run the created program: go run . The program's output will appear in the console terminal: No message? Answer: true Message: "Hello, Socrates!" in subject "people.philosophers" Message: "Hello, Feynman!" in subject "people.physicists" Message: "Hello, Darwin!" in subject "people.biologists" Python Program + NATS As another example, let's consider using the NATS message broker in the Python programming language. First, you need to ensure that the Python interpreter is installed in the system by requesting its version: python --version The corresponding message will appear in the console: Python 3.10.12 Note that this guide uses Python version 3.10.12. Installing PIP To download the NATS client for Python, you first need to install the PIP package manager: apt install python3-pip -y The -y flag helps automatically answer positively to all questions during installation. Installing the Client Now you can install the NATS client for Python: pip install nats-py Creating a Project For the Python program, let's create a separate directory: mkdir nats_python And navigate to it: cd nats_python Writing Code Let's create a file with the program code: nano nats_python.py Its contents will be: import os import asyncio # import NATS client import nats from nats.errors import TimeoutError # get environment variable containing NATS server address servers = os.environ.get("NATS_URL", "nats://localhost:4222").split(",") async def main(): # connect to NATS server nc = await nats.connect(servers=servers) # send message to subject without subscribers to ensure it disappears await nc.publish("people.philosophers", "Hello, Socrates!".encode()) # subscribe to all sub-subjects in "people" subject sub = await nc.subscribe("people.*") try: # extract message msg = await sub.next_msg(timeout=0.1) except TimeoutError: pass # send message to "philosophers" sub-subject of "people" subject await nc.publish("people.philosophers", "Hello, Socrates!".encode()) # send message to "physicists" sub-subject of "people" subject await nc.publish("people.physicists", "Hello, Feynman!".encode()) # extract message and output to console msg = await sub.next_msg(timeout=0.1) print(f"{msg.data.decode('utf-8')} in subject {msg.subject}") # extract message and output to console msg = await sub.next_msg(timeout=0.1) print(f"{msg.data.decode('utf-8')} in subject {msg.subject}") # send message to "biologists" sub-subject of "people" subject await nc.publish("people.biologists", "Hello, Darwin!".encode()) # extract message and output to console msg = await sub.next_msg(timeout=0.1) print(f"{msg.data.decode('utf-8')} in subject {msg.subject}") # unsubscribe from subjects await sub.unsubscribe() # clean up message broker await nc.drain() if __name__ == '__main__': asyncio.run(main()) Now you can run the created script: python nats_python.py The result of its operation will be the following output in the console terminal: Hello, Socrates! in subject people.philosophers Hello, Feynman! in subject people.physicists Hello, Darwin! in subject people.biologists As you can notice, the logic of this Python program doesn't differ from the logic of the Go program. The difference is only in the syntactic constructions of the specific programming language. Conclusion This guide examined the use of the NATS message broker in sequential stages: Downloading and installing NATS from the official GitHub repository Minimal NATS server configuration Managing the NATS server through the console terminal client Using NATS in a Golang program Using NATS in a Python program We downloaded all NATS clients used in this guide (for terminal, Go, and Python) from the official NATS repository on GitHub, which hosts modules and libraries for all programming languages supported by NATS. You can find more detailed information about configuring and using NATS in the official documentation. There are also many examples of using NATS in different programming languages.
24 June 2025 · 13 min to read

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