Which Linux tool or command is surprisingly simple, powerful, and yet underrated?"

socat - connect anything to anything

for example

socat - tcp-connect:remote-server:12345

socat tcp-listen:12345 -

socat tcp-listen:12345 tcp-connect:remote-server:12345

Pandoc.

Converts any rich text format to any other.

nmap *your_local_ip_address*

for example

nmap 192.168.1.43/24 will show you what devices are connected to the local network, and what ports are open there. really useful, for example, when you forgot the address of your printer or raspi yet again.

you can also use it to understand what ports on your computer are open from an attacker's perspective, or simply to figure out what services are running (ssh service).

losetup

it's useful for dealing with virtual disk images. like a real physical hard disk, but it's a file on the computer. you can mount it, format it, and write it to a real physical disk.

it's sometimes used with virtual machines, with iso images, or when preparing a bootable disk.

Not powerful, but often useful, column -t aligns columns in all lines. EG

$ echo {a,bb,ccc}{5,10,9999,888} | xargs -n3
a5 a10 a9999
a888 bb5 bb10
bb9999 bb888 ccc5
ccc10 ccc9999 ccc888
$ echo {a,bb,ccc}{5,10,9999,888} | xargs -n3 | column -t
a5      a10      a9999
a888    bb5      bb10
bb9999  bb888    ccc5
ccc10   ccc9999  ccc888

wait, shell could make matrix multiplication ?
- No, that's just brace expansion.

netstat -tunl shows all open ports on the machine to help diagnose any firewall issues.

netstat is kind of deprecated, ss is more modern (from the iproute2 package) and uses very similar parameters.

Control+r == search through your bash history.

I used linux for ten years before finding out about that one.

Works much better with fzf, but even just default bash it's useful.
So did I until reading this post. Thanks!
i just cat grep .bash_history lol

but this does sound more convenient xD
- Man not even using the history command

xargs

Very true. I used to do magic with xargs when working as a sysadm. Also a good way to mess up on a grand scale. Ask me how I know.
- So, how do you know?

Man

dude
- Bruh

bc

It's a simple command line calculator! I use it all the time.

Very useful for shell scripts that need to do maths as well. I use it to make percentages when stdout has values between 0.0 and 1.0
- I once wrote a bc script that calculated parameters for the Blackman window for a FIR filter. (Had formulas already so not that impressive) Upped the precision until it needed like 30 sec to calculate, completely unnecessarely :).

probably well known at this point but rsync is incredible and I use it all the time

batcat

It's like cat but better. Great for when you just want to look at the contents of a file, without loading a whole text editor.

Oh also, tldr

My procedure for learning how to use a cli command goes tldr page -> --help if the tldr fails to help me -> THEN the full manpage

I like batcat aka bat, but nominate the humble ‘cat’ instead.

Want to copy a disk image to a device? You can use cat for that: cat file.iso>/dev/sdf

What to copy local stdout over ssh? Use cat.

ls -l | ssh myhost 'cat >out.txt'

That’s simple and surprisingly powerful.

jq - super powerful json parser. Useful by hand and in scripts

I love jq, but I wouldn't call it "surprising simple" for anything but pretty-formatting json. It has a fairly steep learning curve for doing anything with all but the simplest operations on the simplest data structures.
- It’s not even pretty or accessible. 2-spaced indentation is incredibly hard to read.
It can also format minimized JSON from cURL API requests
Combine with jc to process CSV files. This is how I get data into my plain text accounting system.
jq and yq are both things I install on pretty much every machine I have.

yes

The most positive command you'll ever use.

Run it normally and it just spams 'y' from the keyboard. But when one of the commands above is piped to it, then it will respond with 'y'. Not every command has a true -y to automate acceptance of prompts and that's what this is for.

Also, you can make yes return anything:

yes no
- I.... did not know that. Thanks, TIL!
That's really neat but also seems like it could be quite dangerous in a lot of use-cases!
- Absolutely, but when you do need it, it's brilliant.
What's the syntax here? Do I go

command && yes

I'm not sure if I've had a use case for it, but it's interesting.
- Also my favourite way to push a core to 100% CPU
  
  yes > /dev/null
- That will just wait for command to finish properly and then run yes.
  
  What you want to run is yes | command, so it spams the command with confirmations.
- true delivers error level 0, false error level 1.
  
  yes && echo True || echo False will always be True.
  
  false && echo True || echo False will always be False.
  
  Common usage is for tools that ask for permissions and similiar. yes | cp -i has the same effect as cp --force (-i: prompt before overwrites).
- Sorry, I should have explained that. it's ~~command | yes~~ yes|command - Eg, yes|apt-get update (Not a great example since apt-get has -y, but sometimes that fails when prompting for new keys to accept)
  
  Edit: I got it backwards, thanks @[email protected] for the correction.
- For some cases I use “|| true”.
  
  The idiom accepts that the preceding command might fail, and that’s OK.
  
  For example, a script where mkdir creates a directory that might already exist.

ip eg:

# ip a
# ip a a 192.168.1.99/24 dev enp160

The first incantation - ip address (you can abbreviate whilst it is unambiguous) gets you a quick report of interfaces, MAC, IPs and so on. The second command assigns another IP address to an interface. Handy for setting up devices which don't do DHCP out of the box or already have an IP and need a good talking to.

Oh and you can completely set up your IP stack, interfaces and routing etc with it. Throw in nft or iptables (old school these days - sigh!) for filtering and other network packet mangling shenanigans.

kde connect

I think a lot of people don't realise that yt-dlp works for many sites, not just YouTube

I used it recently for watching a video from tiktok without having to use their god awful web UI and it was amazing

Also works on Twitch with the added benefit of NOT playing ads (you still get breaks, just with a placeholder screen instead of the commercial).

mpv has yt-dlp support built in, so it can just play the streams directly.
Since everyone keeps mentioning yt-dlp I gotta ask: what's wrong with the original youtube-dl? I keep using it, it works, it's still being updated.
- There are minor feature differences there's also a convenience factor: youtube-dl people for some reason stopped doing releases, so you can't get a fresh version from pypi (only installing from github or their site). Yt-dlp is on pypi, including nightly builds.
- yt-dlp has sponsorblock features, youtube-dl does not.
The huge list of sites can be found here https://github.com/yt-dlp/yt-dlp/tree/master/yt_dlp/extractor

I use fuck to fix typos

this just reminds me of please which runs the previous command with sudo
- sudo !!
  
  Will also run the previous command with sudo, fwiw.
That's fantastic, I can't wait to go home and install it
If you'd map it to just f it's even more handy
- You gain efficiency, but lose fun
That sounds dangerous. I hope it never tries to fix anything with rm
- You have to confirm any command before it runs, so no more dangerous than baseline rm
Game changer!
I use fuckit to fix exceptions

motion

After spending years dealing with shady freeware and junk software on windows, I was floored by how easy and nonchalantly I was able to set up a simple security camera on my PC

When you're ready for a full monitoring package, check out Frigate.

A few that I use every day:

Fish shell
Starship.rs
Broot (a brilliant filesystem navigator)
Helix editor (My favorite editor / IDE, truly the successor to vim IMO)
Topgrade (updates everything)

I heard about helix from you and I've used it for a year and a half or so now, it's by far the best editor I've used so far and I can definitely vouch for it
- Nice!
Just commenting to give more love to helix. It's my favorite "small quick edits" editor.
I've actually been testing with fish recently coming from zsh, though I might wait until 4.0 fully releases before I make a more conclusive decision to move or not.

With that said, I remember looking through omf themes and stumbled onto Starship that branched off one of the themes and really liked the concept.
- One thing that holds people back sometimes is that bash scripts that set environment variables don't work by default. https://github.com/edc/bass is an easy solution
Once Helix gets plugin support and someone makes a Clojure REPL plugin as good as Conjure I am never touching vim again!
- It does have clojure lsp support, but you'll probably have to use a command line for most repls.
Could you explain them in more depth? I opened them and don’t know
- Helix is a terminal based text editor. It’s much like vim / neovim, but unlike those editors it’s good to go right out of the box, no configuration or plugins needed to make it work well.
  
  Topgrade is one I haven’t used, but it looks like its intended purpose is to let you upgrade your apps with one command, even if you use multiple different package managers (I.e. if you were on Ubuntu, you could use it to upgrade your apt packages, at the same time as your snap packages, as well as flatpak, nix, and homebrew if you’ve added those.)
- Fish is a replacement of bash that's a bit more user friendly (has some cool auto completion features out of the box and more sane behaviour like handling of spaces when expanding variables). I personally started to use nutshell recently but unlike fish it's very different from bash.
  
  Starship is a "prompt" for various shells (that bit of text in terminal before you enter the command that shows current user and directory in bash). I haven't used it but AFAIK it has many features like showing current time, integration with git, etc.

zoxide. It's a fabulous cd replacement. It builds a database as you navigate your filesystem. Once you've navigated to a directory, instead of having to type cd /super/long/directory/path, you can type zoxide path and it'll take you right to /super/long/directory/path.

I have it aliased to zd. I love it and install it on every system

You can do things like using a partial directory name and it'll jump you to the closest match in the database. So zoxide pa would take you to /super/long/directory/path.

And you can do partial paths. Say you've got two directories named data in your filesystem.

One at /super/long/directory/path1/data

And the other at /super/long/directory/path2/data

You can do zoxide path2 data and you'll go to /super/long/directory/path2/data

You can do zoxide path2 data

I usually would just do z 2data. Yes, I'm lazy. It's the perfect tool for lazy people.
- Nice! I guess I can be even lazier when navigating!
Sounds a lot like autojump
- I'm not familiar with autojump
Better than fasd?

ddccontrol... it looks complicated on the surface but it's really not and being able to control monitor brightness without fcking around in some garbage monitor OSD is a god sent and should be the standard

tmux - makes managing remote SSH sessions a breeze.

tomb - A little FOSS encryption utility that runs in the CLI. Easy, cute, effective. Tomb Utility

+1 for Caddy, completely replaced nginx. also...

Starship - shell prompt
tmux - terminal multiplexer
parallel - parallel command runner
restic - backup tool
age - modern file encryption

Gripes:

starship and all these shell frameworks are overbloated. Just write your own prompt command and be done with it.

restic, ongoing issue with the author to allow people to backup without a password. Seems like a no-brainer but he's being difficult
- Why would you want password less backups?
  
  I understand if the reason is 'just because', but seriously, why? I just write down the password in a text file for restic --password and I am done.

The pipe (|), which if you think about it is the basis for function composition.

sshfs

all of them

grep goes crazy if you know your regex

Relevant xkcd
- I was expecting this one.
I can never get grep to work consistently on Mac and Linux. Now, ripgrep OTOH....
- That’s because Macs generally use BSD-based command line tools instead of GNU ones. You have to do a lot of Homebrew jiggery-pokery to approximate a GNU environment. Know Your Tools: Linux (GNU) vs. Mac (BSD) Command Line Utilities
Check out my chapter on GNU grep BRE/ERE for those wanting to learn this regex flavor: https://learnbyexample.github.io/learn_gnugrep_ripgrep/breere-regular-expressions.html (there's also another chapter for PCRE)

I don't see anyone mentions htop. So, I will:) Just works, could be installed in any distro. Much more friendly than top but isn't bloated with features as some other alternatives are.

Check out BTOP++ -- it blows htop out of the water.
My fav for the past few years is https://github.com/ClementTsang/bottom
Bashtop if you want something more graphical

awk

simple
- Came here to say both of these things. (Awk and "> simple".)
  
  To be totally honest, I don't think awk is any more complicated than something like grep, it's just that regular expressions get used more often so they're typically more familiar. In the same way that programming languages with c-like syntax (like Java and C#) often feel easier than ones that don't (like Haskell and Clojure).

ncdu

I find myself using tldr a lot since finding out about it. It's just so useful for commands that I don't use enough to commit to memory.

What is it?
- You type tldr and then some command. For example, tldr tar. It gives you a small list of examples and common use cases for the command.

Underrated Both linked projects have over 60k+ stars on GitHub

Pick one

It has not taken over NGINX and Apache yet.

I'm a big fan of screen because it will let me run long-running processes without having to stay connected via SSH, and will log all the output.

I do a lot of work on customers' servers and having a full record of everything that happened is incredibly valuable for CYA purposes.

There is also zellij, which can do the same but also has modern functionality specific for development workspaces!

(Although screen or tmux will still probably be more widely available on remote machines etc)
I'd recommend tmux for that particular use. Screen has a lot of extras that are interesting but don't really follow the GNU mentality of "do one thing and do it well."
- Tmux / Screen is like the emacs/vim of the modern day Linux I think.
  
  Screen is more than capable, but for those who have moved to Tmux, they will absolutely advocate for it.
- When tmux was first released I was already so used to screen that I never really considered switching. What would some convincing arguments be for me to make the effort to switch now?
I know everyone likes tmux but screen is phenomenal. I have a .screenrc I deploy everywhere with a statusbar at the bottom, a set number of pre-defined tabs, and logging to a directory (which is cleaned up after 30 days) so I can go back and figure out what I did. Great tool.
Woah screen is seeing active development again? There was like a decade where it stagnated. So much so that different distros were packaging different custom feature patches (IIRC only Ubuntu had a vertical split patch by default?) Looking at it now, the new screen maintainers had to skip a version to not conflict with forks that had become popular.

When tmux stabilized I jumped ship immediately and never looked back.
- tmux with control mode in iterm is god mode for me on all my machines. Absolutely love it.
nohup is similar
- I've had nohup fail to keep things running after my session ended quite frequently. It's like it just goes to the next step in the process then gives up.
- It's not as useful, sadly. Nohup disconnects standard input, output, and error. With screen or tmux, you can reattach them later.

jq?

I use it occasionally but every time I need to do something a tiny bit more complex than "extract field from an object" I have to spend half an hour studying its manual, at which point it's faster to just write a Python script doing exactly what I need it to do.
- Check out https://www.nushell.sh/ I use it for exactly that, i.e. complex extract and convert files
yq can do both JSON and YAML :)
Funny how this was one of the first tools I learnt once I "seriously" started my linux journey, lol

Underrated? I'd say lftp is the best FTP command line client there is. And Midnight Commander is a very very good file browser. I don't see either praised enough.

The terminal-based file browser space is so filled today but for my part I love what vifm has done for the dual-pane midnight commander concept - it's the same basic idea, uses (somewhat) vim-like bindings by default and is super extensible.
Lftp is fast. Those parallel chunked downloads are not a joke
Great call out! I first used ftp about 30 years ago, and lftp has been my go to for about the last decade. I rarely need it anymore, but I still use it for quickly transferring files with my homebrew switch.
- Did you know it can connect to HTTP directory listings and do the same things it does over S/FTP?

I know tmux is incredibly popular, but a good use case for it that isn’t common is teaching people how to do things in the terminal. You can both be attached to the same tmux session, and both type into the same shell.

Tmux is so much better than screen, and yes that is the hill I will die on

Specially when confined with tmuxp , it's how I handle Game servers that can run headless to start at boot without losing access to giving commands to the server via its server console

nano was and still is vital to me learning and using linux, I will not learn how to use vim so if the distro forces it to be default im not using it.

Why is editing text so convoluted for seemingly no reason.. also hate that vim must be used for certain files.

You can change your hate to love by using vim
- one of my favorite linux youtubers is named vimjoyer so maybe one day I will try to learn it
You can change that by changing your editor global variable
Wow you triggered a lot of vim users !

Maybe give micro a shot :) It's nano but more sane defaults and comes with customization in mind.
vim isn't required for any files, you just followed online tutorials for how to edit those files instead of RTFM

terminal text editing is convoluted because it has to strike a balance between figuring out when a keypress is part of the text you're typing, vs when it's a command you're using, and making sure that all the editor commands the designer wanted are accessible.

vim is great because it allows for thousands more editing commands and macros, and much more customization of the editor, up to allowing plugins that emulate other functionality. As it stands, my setup basically functions as a full, lightweight-ish, multi-language IDE that rivals Emacs or Visual Studio.

On top of all that, I don't have to move my hands away from the homerow of keys to navigate or edit, which may not seem like much, but adds up to a lot of avoid typos and time saved from moving my hands to reach the arrows/delete/home/end/pgup/pgdn.

Some examples:

h, j,k,l move left, down, up, and right respectively, but they can be combined with a number to move that many rows or columns; e.g. 6j will move down 6 rows

dd deletes a line, but using a number + d + a movement will delete that many characters/lines in the path of the cursor: e.g. 34dl will delete 34 characters to the right of the cursor, 12dk will delete 12 lines up.

gg will take you to the first line, G will take you to the last, and number + either will take you to that line: e.g. 3275gg or 3275G will take you to line 3275

and finally you can use /text or regex pattern you want to search for and Enter to search the document for the first occurence below your current location, and then use n to search for the next occurence, or N to search for the previous

That doesn't even scratch the surface (that's just the cheatsheet, which only scratches the surface), but if you can get a handle on only what I've said, and switching between input and command mode (i and Esc respectively), the speedup to navigation alone will make it seem more sensible.

And as always, don't forget to :wq (write to file and quit)
It's for people to memorize hundreds of arcane shortcuts and shit so they can feel like a smug hacker and gloat over the rest of us using other editors and getting just as much done as they are.

Also for graybeards that haven't realized it's not 1985 anymore.
- For the average user you're definitely right, but I will say for the sysadmin of headless systems, having a powerful cli editor is a godsend. While it may seem arcane and unnecessary, learning vim is easier than managing remote x or sshfs or copying files to and from a system.
  
  I didn't learn vim to be a contrarian; I learned it because it seemed (and still seems to be) the path of least resistance for many workflows.
- Wait until you meet an emacs user! ;p
- It's for people that don't want a big bulky IDE and are willing to put a little work in to get used to it. I do all my coding in the terminal with vim and tmux and I like the simplicity and that with two dotfiles I can migrate my whole development environment to whatever PC, server or RaspberryPi that I need.
- I've used Vim for some pretty non-nerdy stuff. Like ripping my DVD collection, when I got to the TV section I had a lot of file names to modify in bulk, and Vim let me do that. Also guitar tablature, the ability to edit plaintext both horizontally and vertically is surprisingly handy. Just having a macro to be able to add a bar line saves a shocking amount of time.
seems like you need to try micro. It's like nano, but with more sensible standard keybinds imho, as well as syntax highlighting and global clipboard use.
Yeah, to this day vim still isn't intuitive for me, so I just use nano as it's either often included or simple to install on most Distros.

Unless a script is hardcoded for vim I haven't had to use it.
- It's weird but VIM is so powerful and I love it but i also agree it wouldn't be the default just an option if you needed it. It's like with notepad ++ on windows it's wonderful but not everyone needs it from day one notepad will work just fine for basic typing.
vim must be used for certain files??
- Cant remember exactly but it had something to do with a file relating to sudo and it only was allowed to be edited with a vim style editor.
igtfo<ESC>
:q!
I used nano when I started but now I am using vim for one year already. I'd recommend taking a few days where you only use vim and I think you will see why people like it. With a few motions you can be much faster than you would be in Nano.
- One of the big reasons I switched to nixos is that I mostly need to use the console only for updating my system by editing the configuration file using nano. I do very little besides that thankfully while the GUI side of linux gets better everyday.
- I’m using Linux since 1998 and still like nano. I can use vi, but prefer nano when it’s available.
Nano is hella confusing too. Since when is ^ = Ctrl?

And why dont they tell you that Ctrl+S Ctrl+C Ctrl+X works?
- ^C has been notation for ctrl-c for decades.
- Since 1968
  
  As for why: arbitrary choice, they just needed a printable character they could show on screen, for when people pressed it and the terminal echoed it back out to them.

Discovered about rg recently and it is cool!

https://github.com/BurntSushi/ripgrep

xargs
parallel
PXE (ohai cobbler)
tee
task-spooler (ts aka tsp)
rpm -V

Nothing new, just forgotten.

task-spooler (ts aka tsp)

This looks amazing. Do you know how well it works in dispatching and tracking jobs over remote servers (over SSH)?
- We've been using tsp at my work for years and it works well. It is just a very basic queueing system so if you can run the job from the command line then you can run it via tsp.
  
  Our workflow is to have concurrent jobs run on the remote servers with cron and tsp but you should be able to trigger remote jobs over SSH also if you prefer to have a single machine in charge of task allocation.

yq is crazy cool for converting between different text-based data formats such as yaml, json, xml, csv and others, and it has a super nice pretty-printing function as well. I use it all the time!

Just be aware that your distroy might come with a yq variant too, but possibly one that isn't as powerful as the one I linked. I know this to be true at least for Ubuntu.

I used jq for something similar before, recently I've discovered Nu Shell and have been using that for converting and analyzing data since a full shell is a lot more powerful than a command (e.g. open a yaml, for each element on key X grab the first element of list Y and export to a CSV)
Can it handle a file that has corrupt json? Or does it just tell you "no"
See also https://github.com/TomWright/dasel

paste. I don't think a lot of people know this command, but it can be handy at times

Using rust rewrite of coreutils you can cp -g to see progress. Set an alias :)

Holy shit I was just talking about cp with progress today. Awesome

CTRL-L to clear your terminal output. Or type clear

Also Ctrl+D to exit any shell and Ctrl+R for reverse searching your history!

I love ncdu for seeing where all my storage is being taken up.

A really simple one but surprisingly useful is cal

Cool cal trick, it knows about the Gregorian calendar reform: cal 9 1752
Very useful for having a quick glance at calendar. Although it's annoying that there's no option to have week start on monday.
- alias cal="cal -m"

I think socat is a really powerful und underrated tool

I’ve used it in high-throughput production environments to do things that netcats can’t.

dd is probably well known, but one of the simplest and most powerful ways to accidentally delete all data on your hard drive. dd if=/dev/random of=/dev/sda

You can destroy it all the same with cp or cat.
ddrescue (or gddrescue) is a great version if you have a sick drive. It'll try to copy the good areas first then go back to hammer on the sick areas.

Not perfect as it doesn't know about the file system so it tries to copy the entire surface, but generally a good tool.
@bamboo @mfat , DD, great tool. Utilize it so often, but it is powerful and dangerous. I always double, triple, quadruple check my target disks with multiple programs to avoid destroying my production workstation. Might be best if I just designated a RPi for the job. 😅

pipeviewer or pv

I've switched from using dd to using pv to write disk images to removable media.
Great call! pv is deceptively powerful. Being able to see progress and rate limit a pipe is incredibly useful.

I'm not sure how underrated it is but the exec feature in find is so useful, there are so many bulk tasks that would just be incredibly difficult otherwise but instead are just one line

Just be careful with files with spaces in the name. There's an incantation with xargs that I always have to look up when I want to use it safely.

GNU datamash (https://www.gnu.org/software/datamash/alternatives/) - handy tool for data munching. There's also https://github.com/BurntSushi/xsv

Wow, I might try learning this over the next few days. Nice replacement for tidyverse on the cli

vd (VisiData) is a wonderful TUI spreadsheet program. It can read lots of formats, like csv, sqlite, and even nested formats like json. It supports Python expressions and replayable commands.

I find it most useful for large CSV files from various sources. Logs and reports from a lot of the tools I use can easily be tens of thousands of rows, and it can take many minutes just to open them in GUI apps like Excel or LibreOffice.

I frequently need to re-export fresh data, so I find myself needing to re-process and re-arrange it every time, which visidata makes easy (well, easier) with its replayable command files. So e.g. I can write a script to open a raw csv, add a formula column, resize all columns to fit their content, set the column types as appropriate, and sort it the way I need it. So I can do direct from exporting the data to reading it with no preprocessing in between.

miniserve

A static file server, I use it for temporary file share in company, just run miniserve . in the folder.

dua

Alternative of du command, run dua i for a text UI

Also useful in this regard, python comes with a sìmple file server built in, python -m http.server --directory /dir/ would serve /dir/ on port 8000.

Use less for checking contents of files. Many people use cat all the time, but I don't like it, because if you do that often, your terminal window quickly gets flooded with stuff, and then you have to scroll up and down if you wanna see a previous output. With less, your file opens in a different "frame", which you can close when you're done.

I'd like to interject for a moment. There is also a tool called bat that is just cat with extra features. It prints out and works just like cat, but when the contents get too big, it works like less. The is syntax highlighting and works with git.

It's replaced my need for cat and less.
Try bat....
Yes! I use less all the time, combine it with grep, etc.
cat <your file> | more
- Useless use of cat award!

Lightweight sudo alternatives, hard to google too. I know ssu and rdo, please mention others.

OpenDoas, or simply doas, as in do [command] as [user]
- Thanks, couldn't get it ever to work tho, and it doesn't come with a default config in Arch.
Why should I use a sudo alternative?
- Because sudo is best suited for server administration, way overengineered (with the occasional critical vulnerability) for desktop use.
  Alternatives can fit the required functionality for desktop use in 150 loc C code while sudo has what, something over 100'000 loc?

awk
the (usually rust-based) coreutils "alternatives" like bat, fd, eza, procs
trash-put (rm with trash integration. But beware that it also operates on directories by default, which rm only does with -r. There should be an option to change that behavior but there isn't. Don't alias rm to this)
wl-copy/paste (or the older one for X11, 'xclip' IIRC. Enables you to do stuff like "cat image.jpg | wl-copy" to copy it to the clipboard. Best alias it to something shorter)
xdg-open (open the file using your associated program for that file type. Alias to "o" or so)
pass (awesome password manager, when you have a GPG key pair. Even better in combination with e.g. wofi)
notify-send (to send GUI notifications from shell scripts)
ledger (plain-text accounting software. If you use Emacs you should take a look at this as it's written by an Emacs dev, and has good integration of course)
nc
nohup

I like btop Maybe not really "unknown", but hey for those that don't know about it, check it out!

I like https://github.com/aristocratos/btop personally. It's way prettier than the normal top command which you use to watch processes to find the one that's hogging all of the CPU or whatever. And it's not so much that it's underrated so much as it's not very well known or distributed by default.

awk

..for parsing the output of other commands quickly and simply. Then that parsed output can be used to create simple log messages or be passed as args to other scripts. Powerful.

awk and sed have always been intimidating for me with that cryptic syntax.
- I agree with your sentiment regarding confusing syntax, however I think that confusion simply requires a calculated approach to dispell it.
  
  It's a prime example of why I use scripts as reminders as much as I use them functionally. I work out the syntax once.. save it to an example script, then save myself 20 minutes of remembering by just $ cat ./path/to/script.sh and copying said syntax.
  
  So if you can change your workflow such that learned things stay around as examples, I feel that you will pick it up much more quickly :)

As someone who has to do installs and admin at work a lot I'm constantly dealing with yum/dnf. I cry when I have to work with AIX.

Don't run killall on aix before reading the man page!
- It sounds scary lol
We install dnf on our AIX boxes. Works okayish.
- I tried grabbing it and couldn't even get it to install. If you have a link to a good install...
What is AIX
- An OS used by IBM on their mainframes. I have to work with it because some big orgs, especially financial and gov, still use it and run our apps on it.
- Maybe it's the old IBM AIX https://en.m.wikipedia.org/wiki/IBM_AIX

Underrated or not widely known?

I love lazygit and I'm still surprised at how many people are shocked when they see it for the first time. Not exactly a command, but a very handy text UI tool.

For more elementary tools, I can't believe how many people know about ! and ctrl+r who don't also know about fc and edit-and-execute-command.

Lazygit perfectly fits my lifestyle:) thanks for sharing

inxi saves you time 90% of the time that you would use for lsXXX commands and grepping. Really useful for quick hardware and kernel module checks.

degit is a tool that will check out a git repo (or a specific branch or commit), but not set it up as a git repo. Basically just downloading a specific commit to a directory.

So just clone a git and delete the .git folder? Seems pretty useless to me.
- If you want to waste bandwidth downloading the entire commit history, go ahead.

mlocate

I immediately had flashbacks of diagnosing bad I/O performance on CentOS 5 servers. That was the week when I learned what updatedb is and why it was always running in the background (there was a lot of files)
Do you have to wear the fedora to run this command?
- No sorry, I should have elaborated. The package name is mlocate but the command is locate. Occasionally run updatedb as it populates an sqlite db with every file on your system that you can then list out using locate followed by the filename you want to locate.
  
  EDIT: Lol. Sorry barely read your reply. Yes, you should wear a fedora while installing mlocate.
I love locate! I have a cronjob that updates the db every night, then I can just find a file without having to think about where it is

edir, can use GUI editors too.

find?

Idk a lot of commands but I think wget for downloading webpages and rsync for syncing devices are pretty awesome

I love httpie for hitting urls when i want to see the headers or body without downloading to a file eg testing an api
The first time I used wget I felt so awesome. I was grabbing some extra music files I think it was for Ur-Quan Masters.

On the subject of editors, joe is just awesome: lightweight, powerful, had coffee coloring and line numbers, and you can choose it with Ctrl+C:)

Bat, a cat alternative.

Lsd, an ls alternative.

Procs, a ps alternative.

Renane, because it's great.

Love LSD. I always install it first with btop and zoxide
- Zoxide? Will check it out. Thanks.

yes

People always sleep on script. It's badass and let's you do goofy things like this while keeping standard terminal formatting: https://github.com/StaticRocket/dotfiles/blob/043e9a56cc9515060188ec4642e4048c0dd6c000/dot_bashrc#L79-L94

From your example, I have a hard time inferring what is it doing.
- Executing a command, capturing all terminal formatting and escape codes so I can do some light manipulation on leading whitespace before dumping it back to the terminal.

watch -g

-g is not documented, what does it do?

Note: this made me discover topless (SFW) and its Caveat section.
- -g, --chgexit Exit when the output of command changes

+1 to caddy. There are some services that set safe headers following the recommendations outlined by Mozilla but others don't control headers as strictly. Caddy is the only web server that I found that supports loose default header values. These values will be selected unless the upstream application specifies their own values.

You can do something similar in nginx but it requires playing with maps and has a little more indirection than I'd like.

Just wish caddy was capable of starting as root and stepping down permissions like Nginx. I have certs being managed by other tools and have to make sure they are installed and chowned for caddy's use when they are cycled.

I just started the process of switching from nginx Proxy Manager to Caddy yesterday, and even before setting up a single rule, I'm enjoying it more than NPM. Really wish I would have heard about it sooner!
- I'm currently using NPM and don't have any problems with it for at least my use case. Is there something I'm missing out on never having tried Caddy, or is it one of those no need to switch if there's Nothing bugging you situations? That last bit is how I feel about Bazzite on the Steam Deck when people ask of they should switch.

glances! Way better than top and does a bazillion cool things!

https://nicolargo.github.io/glances/

I loved glances until I switched to btop with Hot Purple Traffic Light theme, and I doubt I'll switch again. Check it out!
This looks very cool. Thanks for sharing.

Inshellisense is teaching me a lot. :) It's an autocompleter.

https://github.com/microsoft/inshellisense

Also, Atuin for history.

https://github.com/atuinsh/atuin

I really enjoy erdtree a ls replacement

I abused debfoster for years... it kept my machines running very, very clean.

Cool. I'd never heard of this and I've used Debian for years.

I use node as a calculator a lot. It can be dangerous, because it suffers from floating point errors, but it’s generally more powerful than a calculator if you know the Math lib well.

Why not just use python as a calculator then?
- Because I don’t know Python.

The mouse.

Bring on the downvotes. 🎉

Hey, still the quickest way to copy any damn text from a terminal elsewhere is with the mouse. Tmux is a joke for this.

Why can't terminal emulators just make this easy
- Wezterm has made this easy : shift + ctrl + x and your in vim motion moving all over with yank line or word or visual mode. It's super awesome! I never touch my mouse. You can also remap the keymap of course.
🖕😤🖕