Various commands.

Most commands use placeholder path and file names. When using the commands replace them with the actual file paths, user and servernames.

Disk Space

df -h

Lists all partitions and their disk usage

du -hs directoryname/

Returns the total size of everything inside directoryname

du -cha -d 1 /directoryname | sort -nr | head -20

Lists the size of all subdirectories of directoryname

Download Videos / Music

yt-dlp -f 'bestvideo[ext=mp4]+bestaudio[ext=m4a]/best[ext=mp4]/best'

Downloading a video in best quality

yt-dlp -f "bestvideo[height<=1080][vcodec^=avc1]+bestaudio[acodec^=mp4a]/best[height<=1080][vcodec^=avc1][acodec^=mp4a]" --merge-output-format mp4

Download a video in max. 1080p and store it in an mp4 container

yt-dlp -x --audio-format mp3

Download audio only

yt-dlp --ignore-errors -f ba --extract-audio --audio-format mp3 --audio-quality 160K -o "%(title)s.%(ext)s" --yes-playlist

Downloads a playlist as mp3

Download Website

wget --mirror --convert-links --adjust-extension --page-requisites --no-parent https://website.com

Downloads a complete copy of a website

wget -p -k https://website.com/page.html

Downloads a single page of a website.s

String Manipulations

sed -i "s/$OLD/$NEW/g" *.txt

Replace string in multiple files

for file in *; do mv "$file" echo $file | tr ' ' '_' | tr '[:upper:]' '[:lower:]'; done

Change all filenames to lowercase and replace all spaces with underscores in a directory:

xclip -selection clipboard -t image/png -i example.png

Copy an image to the clipboard

cat filename | grep -C 3 searchterm

Display's the content of a file searching for searchterm and displaying 3 lines of context before and after a match.

Time

date --date='TZ="Continent/City" localTZTime Date/Day'

Print local time of a date and time in a different timezone

tzselect

Find the available timezones

Formating an SD card

lsblk

Identify the device (usually /dev/sdb)

sudo umount /dev/sdb*

Unmount everything on the device

sudo wipefs -a /dev/sdb

Wipes the partition table

sudo parted /dev/sdb --script mklabel msdos

Creates a fresh partition table for a FAT32 partition

sudo parted /dev/sdb --script mkpart primary fat32 1MiB 100%

Creates a new FAT32 partition

sudo mkfs.vfat -F 32 -n LABELNAME /dev/sdb1

Format and name the partition

Miscellaneous

command | more

Paging long-scrolling output

whereis applicationname

Find the location of an application

trash-restore filename

Restoring deleted files

pdfunite file01.pdf file02.pdf output.pdf

Combine two pdfs to one

unzip /*.zip

Unzip all archived files inside directory

for f in *.zip; do unzip "$f" -d "${f%.zip}"; done

Extract all .zip files in folder creating a new director with the name of the file for each

ssh-keygen -t ed25519 -f .ssh/key_name

Generates a new SSH keypair

Packages

Install .deb files

sudo dpkg --install packagename.deb

List installed dpkg packages sorted by size

dpkg-query --show --showformat='${Package;-50}\t${Installed-Size}\n' | sort -k 2 -n | grep -v deinstall | awk '{printf "%.3f MB \t %s\n", $2/(1024), $1}'

Updating python packages

python3 -m pip install --upgrade

pip3 install  --upgrade

Fonts

Place font files in /.fonts/ or in /.local/fonts/ and reload the font cache.

fc-cache -fv

Fonts can also be placed in subdirectories for better organisation.

Clearing System Logs

journalctl --disk-usage

journalctl --rotate

sudo journalctl --vacuum-files=5

Set SystemMaxUse=100M in /etc/systemd/journald.conf to limit maximum journaling space.

Use systemctl daemon-reload to update.

For printing commands, see printer.

Add an even in khal

khal new -a "Calendar Name" 240227 17:00 18:00 Event Description

Mounting a remote filesystem with SSHFS

sshfs -o allow_other,default_permissions servername:remote/directory/path local/directory/path

Option allow_other only allowed if user_allow_other is set in /etc/fuse.conf

sudo fusermount3 -u /local/directory

Unmounts the directory

To permanently mount a remote directory, add the following line to /etc/fstab:

servername:remote/directory/path /local/directory/path fuse.sshfs noauto,x-systemd.automount,_netdev,reconnect,identityfile=/home/username/.ssh/id_rsa,allow_other,default_permissions 0 0

Rendering a PDF with form fields with ghostscript

gs -dSAFER -dBATCH -dNOPAUSE -sDEVICE=pdfwrite -sOutputFile=output.pdf input.pdf

Converting an RGB pdf to CMYK with ghostscript

gs -dBATCH -dNOPAUSE -sDEVICE=pdfwrite -sProcessColorModel=DeviceCMYK -sColorConversionStrategy=CMYK -sColorConversionStrategyForImages=CMYK -o output_CMYK.pdf input_RGB.pdf

If you want to convert to a specific CMKY profile, use -sOutputICCProfile=profileName.icc instead of -sColorConversionStrategyForImages=CMYK:

gs -dBATCH -dNOPAUSE -sDEVICE=pdfwrite -sProcessColorModel=DeviceCMYK -sColorConversionStrategy=CMYK -sOutputICCProfile=FOGRA39.icc -o output_CMYK.pdf input_RGB.pdf