Linux

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

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

Pandoc.

Control+r == search through your bash history.

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

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

bc

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

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

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)

Man

I use fuck to fix typos

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

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

xargs

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.

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).

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

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

grep goes crazy if you know your regex

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

kde connect

awk

jq?

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.

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.

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

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

tmux - makes managing remote SSH sessions a breeze.

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

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.

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.

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

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.

sshfs

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.