51 Useful Lesser Known Commands for Linux Users

Linux is known for its vast set of powerful command-line tools that allow users to interact efficiently with the system. While many Linux users are familiar with popular commands like ls, cd, or grep, there are lesser-known but extremely useful commands and shortcuts that can simplify and improve productivity.

We’re happy to share our last five articles on ‘Lesser Known Linux Commands‘, which include more than 50 commands you may not know.

This article puts all five together in one easy guide, giving a short summary of each command, its function, and an example.

1. sudo !!

If you forgot to run a command with sudo, you don’t need to rewrite the whole command. Just type sudo !! and it will execute the last command with sudo.

apt update
Permission denied
sudo !!
sudo apt update

2. python -m SimpleHTTPServer

Creates a simple web page for the current working directory on port 8000.

python -m SimpleHTTPServer

Serving HTTP on 0.0.0.0 port 8000 ...

3. mtr Command

Combines ping and traceroute to show the network status in real time.

mtr google.com

4. Ctrl+x+e

Opens the terminal’s default text editor, allowing you to edit the current command before running it.

For example, Press Ctrl+x followed by e in the terminal to open the command in an editor.

5. nl Command

Outputs the content of a text file with line numbers.

nl file.txt

1   This is line 1
2   This is line 2

6. shuf Command

Randomly selects lines from a file or shuffles the content.

shuf -n 3 file.txt

7. ss Command

Displays socket statistics and active connections.

ss -tuln

8. last Command

Displays the history of last logged-in users.

last

9. curl ifconfig.me

Shows the machine’s external IP address.

curl ifconfig.me

10. tree Command

Displays files and directories in a tree-like structure.

tree

11. pstree

Displays a hierarchical view of running processes.

pstree

12. <space> Command

Prevents the command from being saved in the history.

<space> ls

13. stat Command

Displays detailed status information of a file or filesystem.

stat file.txt

14. <alt>. and <esc> .

Reuses the last argument of the previous command.

echo foo
<alt>.

15. pv Command

Simulates Hollywood-style text streams.

echo "Loading..." | pv -qL 10

16. mount | column -t

Displays mounted filesystems in a well-formatted manner.

mount | column -t

17. Ctrl + l

Clears the terminal screen instantly by pressing Ctrl + l in the terminal.

18. curl Command

Fetches unread Gmail messages in the terminal.

curl -u username --silent "https://mail.google.com/mail/feed/atom" | perl -ne 'print "$1\n" if /<title>(.*)<\/title>/'

19. screen Command

Detaches and reattaches long-running processes from the terminal.

screen -S session_name

20. file Command

Identifies the type of a file.

file file.txt

21. id Command

Prints user and group ID information.

id

22. ^foo^bar

Replaces foo with bar in the previous command.

echo foo
^foo^bar

23. > file.txt

Flushes the content of a file from the command prompt.

> file.txt

24. at Command

Schedules commands to be run at a later time.

echo "shutdown now" | at 23:00

25. du Command

Shows the size of files and folders within the current directory.

du -h --max-depth=1

26. expr Command

Solves simple mathematical calculations in the terminal.

expr 3 + 5

27. look Command

Checks for a word in the dictionary.

look apple

28. yes Command

Repeatedly outputs a string until interrupted.

yes "I will study Linux!"

29. factor Command

Shows all the factors of a given number.

factor 12

30. ping Command

Pings a host with audible feedback when it comes online.

ping -i 60 -a 8.8.8.8

31. tac Command

Outputs the content of a file in reverse order.

tac file.txt

32. strace Command

Debugging tool to trace system calls.

strace ls

33. disown Command

Runs a command in the background even after the terminal is closed.

sleep 1000 &
disown -a && exit

34. getconf Command

Displays the system architecture (32-bit or 64-bit).

getconf LONG_BIT

35. while Command

Displays the date and time at the top-right corner of the terminal.

while sleep 1; do tput sc; tput cup 0 $(($(tput cols)-29)); date; tput rc; done &

36. convert Command

Converts the output of a command into an image.

convert input.jpg output.png

37. watch Command

Displays an animated digital clock in the terminal.

watch -t -n1 "date +%T|figlet"

38. host and dig Commands

DNS lookup utilities.

host google.com
dig google.com

39. dstat Command

Generates real-time system resource statistics.

dstat

40. bind Command

Displays all Bash key bindings.

bind -p

41. touch Command

Forces a file system check on the next reboot.

sudo touch /forcefsck

42. lsb_release Command

Prints Linux distribution information.

lsb_release -a

43. nc Command

Checks if a specific port is open.

nc -zv localhost 22

44. curl ipinfo.io

Outputs geographical information about an IP address.

curl ipinfo.io

45. find Command

Lists all files owned by the user xyz.

find . -user xyz

46. apt Command

Installs all build dependencies for a package.

sudo apt build-dep vim

47. lsof Command

This command lists all services or processes that are currently listening on TCP port 80.

lsof -iTCP:80 -sTCP:LISTEN

48. find -size +100M

This command searches for all files and folders that are larger than 100 megabytes in the current directory and its subdirectories.

find . -size +100M

49. pdftk Command

pdftk is a powerful command-line tool that allows you to manipulate PDF files, including merging multiple PDF files into one.

pdftk file1.pdf file2.pdf cat output combined.pdf

50. ps -LF -u user_name

This command displays all processes and threads for a specified user, including detailed information about each thread’s status.

ps -LF -u john

51. startx — :1

This command starts a new X session on display :1, which is useful for running multiple graphical user interfaces simultaneously on different screens.

startx -- :1

That’s all for now! Don’t forget to share your thoughts in the comment section. This isn’t the end of lesser-known Linux commands; we’ll continue bringing more to you in our upcoming articles.

I’ll be back soon with another interesting and useful piece for our readers. Until then, stay tuned and connected to Tecmint.com!