DEV Community: Nivethithaa Saravanavel

Linux Commands — nohup, Zip & Disk Management

Nivethithaa Saravanavel — Thu, 09 Oct 2025 11:09:05 +0000

nohup and Background Process

nohup (short for no hang up) is used to run a command or program in the background.

The process continues even if you close the terminal tab.
It stops when you shut down the system.
Without nohup, closing the terminal will terminate the process.

Common Commands

Command	Description
`nohup program_file`	Runs the given program in the background.
`nohup program_file >> storing_file`	Runs the program in the background and stores the output in another file (`storing_file`). (Press Enter twice to continue)
`top`	Displays all currently running processes.
`ps`	Shows the status of active processes (Process Status).
`ps -aux`	Lists detailed information about all running processes.
`cat storing_file`	Displays the entire log content of a stored background process.
`tail -f storing_file`	Shows the last 10 lines and updates live as new logs appear.
`tail -10 storing_file`	Displays only the last 10 lines of the file.
`kill -9 process_id`	Forcefully stops a process using its process ID (find it using `ps -aux`).
`grep file_name`	Searches for a matching pattern inside a specific file.

Zip and Unzip Commands

Command	Description
`sudo apt install zip`	Installs the `zip` package.
`zip zip_name.zip file_name`	Compresses a single file.
`zip -r zip_name.zip folder_name`	Compresses a folder recursively (includes all sub-files and directories).
`unzip zip_name.zip`	Extracts the contents of a zip file.

Disk Commands

Command	Description
`df -h`	Displays the disk space usage of all drives (in human-readable format).
`du -sh`	Shows how much disk space a particular file or directory uses.

Quick Summary

Use nohup to run programs in the background safely.
Use ps, top, and kill to manage processes.
Use zip and unzip for file compression.
Use df and du to monitor disk usage.

linux - cd,ls,Hard&Soft Link

Nivethithaa Saravanavel — Wed, 08 Oct 2025 08:50:02 +0000

Linux Basic Commands — `cd`, `ls`

Change Directory (`cd`)

Command	Description	Example/Notes
`cd /home/userName`	Moves to the user’s home directory.
`cd ~/`	Shortcut for `/home/username`.
`mkdir demo`	Creates a new directory named `demo`.
`mkdir -p abc/cde/demo`	Creates nested directories recursively.
`cd ..`	Moves out of the current directory (to the parent).
`cd ../..`	Moves up two levels in the directory hierarchy.
`cd`	Moves directly to the home directory.

List Directory Contents (`ls`)

Command	Description	Example/Notes
`ls`	Lists all files and directories.
`ls -lstr`	Lists files with metadata (permissions, size, etc.) in sorted order.
`ls -a`	Shows all files, including hidden ones (those starting with `.`).
`ls *end`	Lists files ending with “end”.	Example: `ls *txt` shows all files ending with `.txt`.
`ls start*`	Lists files starting with “start”.	Example: `ls demo*` shows all files starting with “demo”.

Hard link and soft link

Hard Links

ln original_file new_named_file

Explanation:

B*oth files point to the same data* on disk.
Changes made in one file affect the other.
Deleting one file does not affect the other, as the data still exists as long as one link remains

Soft Links (Symbolic Links)

Command:

ln -s original_file demo_file

Explanation:

The soft link points to the path of the original file, not the data itself.
If the original file is deleted, the soft link becomes broken (it remains but points to nothing).

Aliases

Definition:

An alias is a shortcut that allows you to assign a** short name **to a long command or path.

Example:

alias sh="/home/nive/demo/test/abc/"

Now, typing sh will take you to /home/nive/demo/test/abc/.

Important Notes:

This alias works only for the current terminal session.
To make it permanent, add it to the ~/.bashrc file, then run:

source ~/.bashrc

To make it permanent, add it to the ~/.bashrc file, then run:

source ~/.bashrc
Command:

ln original_file new_named_file

Command:


bash
ln original_file new_named_file

Linux-Basics Commands & File Operations

Nivethithaa Saravanavel — Tue, 07 Oct 2025 14:38:18 +0000

What is Linux?

Linux is an open-source operating system based on Unix, used to run computers, servers, and mobile devices.
It’s known for its stability, security, and flexibility, and powers systems like Android, servers, and supercomputers.

Installing Linux on Windows (WSL)

to install Linux in windows using WSL (Windows Subsystem for Linux):
This allows you to run Linux directly on Windows without a virtual machine.

wsl --install

Basic Linux Commands

Command	Description
`pwd`	Shows the present working directory
`uname -a`	Displays system information
`whoami`	Shows the current username
`clear` or `Ctrl + L`	Clears the terminal screen
`history`	Displays previously used commands
`mkdir directory_name`	Creates a new directory
`cd directory_name`	Changes to the specified directory

Working with the vi and nano Editors

File Editing Commands

Command	Description
`vi file_name.extension`	Create or open a file in vi editor
`nano file_name`	Open file in nano editor
`i`	Switch to insert mode in vi to add content
`Esc + :wq`	Save changes and exit vi
`Esc + :q!`	Exit vi without saving

Listing and Managing Files

Command	Description
`ls`	List all files and directories
`sudo`	Execute commands as an admin
`apt-get install package_name`	Install software in Ubuntu
`Ctrl + Shift + C`	Copy text from terminal
`Ctrl + Shift + V`	Paste text into terminal
`touch file_name`	Create an empty file
`rm *`	Remove all files in the current directory
`rm *.txt`	Remove all `.txt` files in the directory
`cat file_name`	Display file content
`cp old_file new_file`	Copy a file
`mv old_name new_name`	Rename or move a file
`cat >> file_name`	Append content to a file
`echo "text" >> file_name`	Directly append text to a file from terminal
`history >> history.txt`	Save command history to a file

DEV Community: Nivethithaa Saravanavel

Linux Commands — nohup, Zip & Disk Management

nohup and Background Process

Common Commands

Zip and Unzip Commands

Disk Commands

linux - cd,ls,Hard&Soft Link

Linux Basic Commands — cd, ls

Change Directory (cd)

List Directory Contents (ls)

Hard link and soft link

Hard Links

Explanation:

Soft Links (Symbolic Links)

Command:

Explanation:

Aliases

Definition:

Example:

Linux-Basics Commands & File Operations

What is Linux?

Installing Linux on Windows (WSL)

Basic Linux Commands

Working with the vi and nano Editors

File Editing Commands

Listing and Managing Files

Linux Basic Commands — `cd`, `ls`

Change Directory (`cd`)

List Directory Contents (`ls`)