UNIX basics

Tools:

Input reading:

• echo - echo what text is in front of the command
• cat - concatonate (aka) print the content of a file
• wget - network downloader
• sed - to read specific file lines: sed -n LINENUMBERp e.g sed -n 4p sed -n 5,10p
• wc - word/line/character counter
• dadadodo - markov-chain based text generator
  • cat myfile.txt | dadadodo -

ascii art

• figlet
• toilet
• cowsay
• jp2a
  • install it: sudo apt-get install jp2a
  • jpg image
  • do the conversion

=audio

• text-to-speech: espeak

social tools

• write username - chat with the users
• wall - message to all users

=chaining programs aka piping

echo HI WORLD | figlet -f /home/pi/figlet-fonts/ticksslant.flf > /dev/ttyUSB0
echo "yolo" | figlet -f /home/pi/figlet-fonts/weird.flf > /dev/ttyUSB0
echo "yolo" | figlet -f /home/pi/figlet-fonts/madrid.flf

Text Processing:

• sed - stream editor for replacing terms/character. e.g. where e is replaced by 3: sed 's/e/3/g'

cat mona.txt | sed 's/0/?/g'
cat mona.txt | sed 's/e/3/g'| sed 's/o/0/g'| sed 's/a/4/g'

• sort - sort (alphabetically) lines of text files

sort --random-sort userlist.txt | head -n 1 

cat silvio.txt | dadadodo -c 1 - | espeak