Useful commands

Chester Wyke October 19, 2023 Updated: April 15, 2025 #debian

Find which package contains a particular file

apt-file

Consume CPU resources

cat /dev/zero > /dev/null

Check which shells are available

cat /etc/shells

Go back to previous directory

cd -

Show largest folder/files

du -a -BM . | sort -n -r | head -n 30

Set environment variables in bash

export VAR=abc

Check what type of file something probably is

file

Search for a file/folder

find -name "PATTERN"

Show command history

history

Show IP Addresses

ip -c a

Show default gateway and routes

Source: https://www.rootusers.com/how-to-display-routing-table-in-linux/

ip -c r

Kill a running process

Where pid is the process ID of the process to kill or

kill pid

or where program is the name of the program to kill (see more on pidof here)

kill $(pidof program)

Set static route

Where 192.168.0.0/16 is the network and mask you want to set the route for and 192.168.0.1 is the gateway (It auto detected the interface when I tried it.)

sudo ip route add 192.168.0.0/16 via 192.168.0.1

Check route that will be used for address

Source: Faster than Lime - Use ip route help to see more info.

ip route get 8.8.8.8

See installed kernels

find /boot/vmli*

Consumes RAM (And CPU)

memtester

Show network devices

nmcli device status

Get the PID(s) of a process

Where program is the name of the command that started the process (what that shows in the System Monitor)

pidof program

Check which shell is in use

ps -p $$

Get SHA1 hash of a file

sha1sum

Get SHA256 hash of a file

sha256sum

Start Discord Minimized

snap run discord --start-minimized

Get file “properties”

stat

Check system to see which sensors are available

sudo sensors-detect

See bluetooth logs

sudo systemctl status bluetooth

Get a checksum for a file

Source: https://www.baeldung.com/linux/sha-256-from-command-line

The source also shows how to verify against the checksum file

sha256sum my_file.txt
sum my_file.txt

Get checksum for a string

echo string | sha256sum

Manage TexLive Packages

Was already installed on my system not sure from where or when. However it was a very old version and after I set it up for use using tlmgr init-usertree (required for debian). I tested it using tlmgr info algorithm and got the following:

tlmgr: Local TeX Live (2021) is older than remote repository (2024).
Cross release updates are only supported with
  update-tlmgr-latest(.sh/.exe) --update
See https://tug.org/texlive/upgrade.html for details.

Given than the new install was going to be over 7GB I abandoned this option.

tlmgr

Move files to trash from command line

trash

Check version of linux in use

uname -a

See power status for connected devices

upower --dump

Watch the sensor stream

watch sensors