Linux Terminal Command: tail

The tail command is an essential tool in File Manipulation & Viewing. In this tutorial, we will explore what tail does, look at everyday examples, and cover advanced options to supercharge your command-line workflow.

Concept & Explanation

The tail command displays the ending lines of a file. It is the standard tool for monitoring active logs as they are appended to by servers.

Common Options & Syntax

tail [options] [arguments]

Here are the most common flags used with tail:

Simple Usage: Basic default commands.
Detailed View: Shows diagnostic information.
Advanced Actions: Can chain parameters for scripting.

1. Interactive Example (Simple)

Here is how most people run the command:

# Example
tail error.log

What it does: Prints the last 10 lines of ’error.log'.

2. Power-User Example (Advanced)

For scripting and advanced diagnostics, use this configuration:

# Advanced
tail -f -n 100 /var/log/syslog

What it does: Outputs the last 100 lines and keeps the file open (-f), streaming new additions in real time.

⚙️ Warning & Common Pitfalls

[!WARNING] If you monitor a log file that is rotated (replaced by logrotate), standard tail -f will lose track of the file. Use tail -F to track by file name instead of file descriptor.

Here are some related posts on cli_tty1 you might want to check out:

rm : Remove files or directories.
cp : Copy files and directories.
mv : Move or rename files and directories.