Advanced Linux Command-Line Utilities

This guide covers a collection of powerful utilities for system monitoring, networking, file management, and more, aimed at enhancing productivity and control in the terminal.

System Monitoring and Performance

These tools help you monitor your system's resources, performance, and boot process.

Command	Description	Explanation	Alternatives
btop	A resource monitor showing usage for processor, memory, disks, network, and processes.	A visually appealing and feature-rich real-time system monitor; a significant upgrade over top.	htop, top, glances
glances	A cross-platform system monitoring tool.	Provides a large amount of information in a single screen, including CPU, memory, disk I/O, network, and processes.	btop, htop
iotop	Monitor I/O usage by processes.	A top-like interface showing which processes are responsible for disk I/O, useful for identifying bottlenecks.
ps	Report a snapshot of the current processes.	The standard command for listing currently running processes on the system.	procs, htop
procs	A modern replacement for ps.	Offers user-friendly output with color-coding, tree view, and TCP/UDP port display.	ps, htop
watch	Execute a program periodically.	Runs a command repeatedly, displaying its output to monitor changes over time.
progress	Monitor the progress of coreutils commands.	Shows the progress of commands like cp, mv, dd, tar, and gzip as they are running.
systemd-analyze blame	Show how long each systemd unit took to start.	Helps identify services slowing down the boot process by showing their initialization time.
systemd-analyze critical-chain	Show the critical chain of units for system startup.	Displays a tree of the time-critical chain of units to understand boot dependencies and bottlenecks.

Network Utilities

Tools for network analysis, troubleshooting, and remote communication.

Command	Description	Explanation	Alternatives
mosh	A robust mobile shell for remote connections.	Offers a more robust connection than SSH, especially on unstable networks, supporting roaming and session resumption.	ssh, et
et (Eternal Terminal)	A remote shell that automatically reconnects.	Similar to mosh, it provides a reliable shell that survives network outages and IP address changes.	mosh, ssh
mtr	A network diagnostic tool.	Combines ping and traceroute to provide a real-time view of the network path and packet loss.	ping, traceroute
dig	DNS lookup utility.	A powerful tool for querying DNS servers and troubleshooting DNS issues.	dog, nslookup
dog	A command-line DNS client.	A modern, user-friendly alternative to dig with a clean, colorful output.	dig, nslookup
tcpdump	A command-line packet analyzer.	Captures and analyzes network traffic on a specific interface for troubleshooting and security analysis.	tshark, wireshark
tshark	A terminal-oriented version of Wireshark.	The command-line equivalent of Wireshark, allowing for detailed packet inspection from the terminal.	tcpdump
termshark	A terminal UI for tshark.	Provides a user-friendly, interactive terminal interface for tshark, making packet analysis easier.	tshark, tcpdump
lsof	List open files.	Can list all open network connections and the processes using them, which is useful for network troubleshooting.	netstat, ss
ipcalc	An IP address calculator.	A command-line tool for calculating IP information like netmasks, broadcast addresses, and network ranges.

Search, Navigation, and Data Manipulation

Tools to find files, navigate the filesystem efficiently, and process data streams.

Command	Description	Explanation	Alternatives
rg (ripgrep)	A very fast recursive search tool.	Searches for text within files at extreme speed, respecting .gitignore by default.	grep, ag
fd	A fast and user-friendly alternative to find.	A modern replacement for the find command with a more intuitive syntax and better performance.	find
fzf	A command-line fuzzy finder.	An interactive tool for searching files, command history, processes, and more.	skim
zoxide	A smarter cd command.	Tracks frequently visited directories, allowing you to jump to them quickly using partial names.	autojump, fasd
jq	A lightweight command-line JSON processor.	An essential tool to slice, filter, map, and transform JSON data from the command line.	gron

Terminal Enhancements

Utilities designed to improve the features, usability, and experience of the terminal itself.

Command	Description	Explanation	Alternatives
wezterm	A GPU-accelerated cross-platform terminal emulator.	A powerful, customizable terminal with features like multiplexing, ligatures, and GPU rendering.	alacritty, kitty
terminator	A terminal emulator with multiple panes.	Allows you to split a single terminal window into multiple panes to manage several shell sessions at once.	tmux, wezterm
tmux	A terminal multiplexer.	Creates and manages multiple terminal sessions in one window. You can detach and reattach, keeping processes running.	screen
asciinema	A tool for recording and sharing terminal sessions.	Records terminal activity as a lightweight, text-based animation, great for tutorials and demos.	script

Development and Automation

Tools for software development, automation, and task management.

Command	Description	Explanation	Alternatives
lazydocker	A terminal UI for Docker.	Provides an interactive terminal interface for managing Docker containers, services, and images.	docker-compose, portainer
lazygit	A terminal UI for Git.	Offers a simple terminal interface for Git, allowing common operations with single keystrokes.	gitui, tig
fabric	A Python library for streamlining SSH for deployment.	Automates administrative tasks over SSH, often used for deploying applications and managing remote servers.	ansible, saltstack
ollama	Run large language models locally.	Allows you to download and run large language models on your own machine.
taskwarrior	A command-line task manager.	A powerful and flexible to-do list manager that operates entirely from the command line.	todo.txt, khal

Moreutils: A Collection of Useful Extras

moreutils is a package of small, sharp utilities that solve common command-line problems but are not included in the standard coreutils package.

• chronic: Runs a command and hides its output unless the command fails (returns a non-zero exit code). Incredibly useful for cron jobs. chronic ensures you only receive an email from a cron job if it fails, which is usually the only time you care.

  • Example: chronic /path/to/my/backup_script.sh

• combine: Combines lines from two files based on boolean logic (AND, OR, NOT, XOR). It performs set operations on the lines of files. For example, combine fileA and fileB outputs only the lines present in both files.

  • Example: combine users_in_group.txt and users_with_access.txt

• errno: Look up errno names and descriptions. Helps you decipher system error codes by showing their standard names and descriptions.

• ifdata: Get network interface information. A simple script to check for the existence of a network interface or get information about it, like its IP address.

• ifne: (If Not Empty) Runs a command only if its standard input is not empty. Prevents a command in a pipeline from running if there's no data for it to process, which can avoid errors.

  • Example: find . -name "*.bak" | ifne xargs rm

• isutf8: Checks if a file or standard input is valid UTF-8 encoded text. A simple utility that exits with a status of 0 if the input is valid UTF-8 and 1 otherwise. Useful for validating text encoding in scripts.

  • Example: if isutf8 somefile.txt; then echo "File is valid UTF-8"; fi

• lckdo: Executes a command while holding a lock file. A simple way to ensure that only one instance of a script can run at a time.

  • Example: lckdo /var/run/myjob.lock /path/to/my/sensitive_script.sh

• mispipe: Pipes two commands, but the exit status is taken from the first command, not the last. Useful when you need to know if the first command in a pipe succeeded, regardless of the second command's outcome.

  • Example: mispipe "grep -q 'ERROR' log.file" "echo 'Found an error'"

• pee: Acts like tee but for pipes, sending its input to multiple command pipelines. While tee writes to files and stdout, pee sends the data stream to other commands for simultaneous, independent operations.

  • Example: cat access.log | pee "grep 'GET /' > gets.log" "grep 'POST /' > posts.log"

• sponge: Soak up all input before writing to a file. Allows you to read from and write to the same file in a pipeline, which is not possible with standard shell redirection.

• ts: Add a timestamp to each line of input. A simple utility that prepends a timestamp to each line of output from another command.

• vidir: Edit the contents of a directory in a text editor. Allows you to rename files in a directory by editing their names in a text editor, which is efficient for bulk renaming.

• vipe / vip: Edit a command's output in a text editor in the middle of a pipeline. Lets you manually edit the output of one command before it gets passed as input to the next command.

  • Example: grep "user:" /etc/passwd | vipe | cut -d: -f1,5