Skip to content

Linux who Guide

Mattscreative edited this page Dec 5, 2025 · 2 revisions

Linux who Guide

Complete beginner-friendly guide to who on Linux, covering Arch Linux, CachyOS, and other distributions including viewing logged-in users, login information, and system activity.


Table of Contents

  1. Understanding who
  2. who Basics
  3. Viewing Users
  4. Login Information
  5. Troubleshooting

Understanding who

What is who?

who shows who is logged in.

Uses:

  • Logged in users: See active users
  • Login times: When users logged in
  • Terminals: Which terminals are in use
  • System activity: Monitor system usage

Why it matters:

  • Security: See who's on system
  • Monitoring: Track system usage
  • Troubleshooting: Debug login issues

who Basics

List Users

Show logged in:

# Show all logged in users
who

# Output format:
# username tty1 2024-01-15 10:00 (:0)

Detailed Information

More details:

# Show with details
who -a

# Show with headers
who -H

Viewing Users

Current User

Show yourself:

# Show current user
who am i

# Or
whoami

All Information

Complete info:

# All information
who -a

# Includes:
# - Username
# - Terminal
# - Login time
# - Remote host

Login Information

Boot Time

System uptime:

# Show boot time
who -b

# System boot time

Login History

Recent logins:

# Show login history
last

# Or
lastlog

Troubleshooting

who Not Found

Check installation:

# Check who
which who

# Usually in coreutils
# Install if missing
sudo pacman -S coreutils

Summary

This guide covered who usage, user listing, and login information for Arch Linux, CachyOS, and other distributions.


Next Steps


This guide covers Arch Linux, CachyOS, and other Linux distributions. For distribution-specific details, refer to your distribution's documentation.

Clone this wiki locally