UNIX basics

From XPUB & Lens-Based wiki

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