List of useful commands

commands.sh

# handy linux commands

# get video card specs
lshw -C video
lspci | grep -i vga

# distro specs
uname -m && cat /etc/*release

# distro name
% lsb_release -cs
xenial

# packages (drivers) installed
dpkg -l | grep nvidia

# mounted partitions
df -h

# summary of disk space used by directories
du -hs *

# most recent sys messages
dmesg | tail

# connected devices
lsusb
lsusb -d vendorId:productId -v

# nyancat
nc -v nyancat.dakko.us 23

# watch memory every 5s
watch -n 5 free -m

# make a GIF from a screencast
ffmpeg -i mem-01.ogv frames/ffout%03d.png
convert -loop 0 frames/ffout* mem-01.gif
convert mem-01.gif -fuzz 10% -layers Optimize optimized.gif

# gif to mp4 and viceversa
ffmpeg -f gif -i infile.gif outfile.mp4

# ogv to mp4
ffmpeg -i out.ogv -strict -2 out.mp4

# from png to pdf
convert grid.png -gravity center grid.pdf

# clip video
ffmpeg -i take-3.mp4 -ss 00:00:03 -t 00:02:04 output.mp4

# crop a video
ffmpeg -i in.mp4 -filter:v "crop=out_w:out_h:x:y" out.mp4

# speed up a video
ffmpeg -i take-4.mp4 -filter:v "setpts=0.5*PTS" take-4-faster.mp4

# timelapse a video
ffmpeg -i input.mp4 -r 1 -f image2 frames/%05d.png
ffmpeg -i frames/%05d.png timelapse.mp4

# resize video
ffmpeg -i larger.mp4 -filter:v scale=720:-1 -c:a copy smaller.mp4

# resize image
convert IMG_2000.jpg -resize 1024x IMG_2000_resized.jpg

# remove audio from video
ffmpeg -i loud.mp4 -c copy -an muted.mp4

# pull video metadata
exiftool take.mp4

# extract audio from a youtube URL
youtube-dl https://www.youtube.com/watch?v=tN12Tg5ttpk -f mp4
ffmpeg -i ytcracker\ -\ meganerd-tN12Tg5ttpk.mp4 meganerd.mp3

# play mp3 from the cli
ffplay ~/Music/meganerd.mp3
mplayer ~/Music/meganerd.mp3

# Sort ‘ps’ output by memory (RAM), from high to low
ps aux --sort -rss

# connect to VPN from the cli
nmcli con up id sub.kewlvpn.lol

# check avail networks
nmcli con

# incognito
firefox --private-window
chromium-browser --incognito &

# record action
cnee --record -o automate-this.xnr --mouse --events-to-record 1000 --time 2
cnee --replay -f automate-this.xnr --time 2

# adding password to PDF
pdftk [mydoc].pdf output [mydoc.128].pdf owner_pw [foo] user_pw [baz]

# docker (remove/stop all containers)
docker stop $(docker ps -a -q)
docker rm $(docker ps -a -q)

# docker (remove all images)
docker rmi $(docker images -q)

# compress directory
tar -zcvf archive-name.tar.gz directory-name

# encryption
gpg -c filename
aescrypt -e "File" 
zip --encrypt file.zip.enc file # prompt for password

# git - updating author
git rebase -i -p <commit-to-start-from>
git commit --amend --author="John Snow <jsnow@thewall.com>"

# git - get latest commit id
echo $(git log --format="%h" -n 1)

# delete all containers named mongo
docker rm $(docker ps -a | grep mongo | cut -f 1 -d' ')

# delete all node_module directories recursively
find . -name 'node_modules' -type d -prune -exec rm -rf '{}' +

# rotate a screen
# https://askubuntu.com/questions/95812/how-can-i-rotate-my-display-in-the-most-easy-way
xrandr --output HDMI-1 --rotate inverted

# delete old files
rm $(ls -lh *csv | grep "Dec 18" | cut -d' ' -f11)

# find process running on a port
ss -lptn 'sport = :3000'

References:
https://video.stackexchange.com/questions/4563/how-can-i-crop-a-video-with-ffmpeg#4571
https://stackoverflow.com/questions/19176359/how-to-get-the-last-commit-id-of-a-remote-repo-using-curl-like-command#19176626

Removing vbox disks
VBoxManage closemedium disk 633a54a5-c3c0-4330-b371-9d448ae28c4c
VBoxManage closemedium disk 7ef3723f-e960-4e68-9b8c-ef8d65b1474b
https://myshittycode.com/2013/11/23/virtualbox-failed-to-delete-the-storage-unit-of-the-hard-disk-pathhard-disk-vdi-cannot-close-medium-pathhard-disk-vdi-because-it-has-n-child-media/