10 Hidden Linux Commands Every Sysadmin Should Know

In this article we explore several little‑known Linux commands that can be extremely useful for managing both desktop and server systems.

1. Space command (prefix with spaces)

Any command entered after one or more leading spaces is not recorded in the history file. Try running five common commands (e.g., ls, pwd, uname, echo "hi", who) with a leading space and then check the history; the last command will be missing.

ls pwd uname echo "hi" who history

2. stat command

The stat command displays detailed status information about a file or filesystem, including size, blocks, permissions, access, modification, and change timestamps.

stat 34.odt

3. Alt+. (or Esc . ) shortcut

Pressing Alt (or Esc) followed by a period inserts the last argument of the previous command at the prompt, allowing quick reuse of arguments.

4. pv command

pv

can simulate a live‑typing effect for any text stream. Install it via apt or yum if missing.

echo "Tecmint [dot] com is the world's best website for qualitative Linux article" | pv -qL 20

5. mount | column -t

Pipe mount through column -t to format the list of mounted filesystems into neat columns.

mount | column -t

6. Ctrl+L command

Press Ctrl+L to instantly clear the terminal screen without typing clear.

7. curl command for unread mail

Use curl with HTTP authentication to fetch the Gmail Atom feed and extract unread mail titles. The command prompts for the password at runtime.

curl -u [email protected] --silent "https://mail.google.com/mail/feed/atom" | perl -ne 'print if /<(title|name)>(.*)<\/>/;'

8. screen command

screen

lets you detach a long‑running process from the current terminal and re‑attach later. Start a job with screen ./script.sh, detach with Ctrl+A d, and re‑attach using screen -r <session_id>.

./long-unix-script.sh screen ./long-unix-script.sh # detach: Ctrl+A d screen -r 4980.pts-0.localhost

9. file command

The file command reports the type of a given file, e.g., OpenDocument Text for 34.odt.

file 34.odt

10. id command

id

prints the effective user and group IDs, along with supplementary groups.

id

These commands provide powerful shortcuts and insights for everyday Linux usage.