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

Pandoc.

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

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).

Control+r == search through your bash history.

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

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

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.

bc

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

Man

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

xargs

probably well known at this point but rsync is incredible and 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

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

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.

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 use fuck to fix typos

kde connect

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

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

grep goes crazy if you know your regex

awk

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

+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