Shell

• Shell Style guide
• ShellCheck => finds bugs in your shell scripts
• Match command-line arguments to their help text => explainshell
• Replaces last digit of given software version by a ‘x’:
  echo "5.6.3" | grep -Eoh "[0-9+\.]+\." | xargs -I % echo "%x"
• Converts all files to Unix line endings:
  find . -type f -print0 | xargs -0 dos2unix
• Kills all occurency of searched entry:
  ps aw | grep <pgm> | grep -v 'grep' | cut -d '?' -f1 | xargs kill -9
• To create a compressed file:
  tar -cvzf *filename.tar.gz <directory/*>
• To extract the contents of a file:
  tar -xvzf <filename.tar.gz>
• Adds execute permission for the owner of the file:
  chmod u+x <file>
• List sizes of current directory recursively:
  du -hs *
• Status of last command (‘0’ => OK, ‘1’ => KO):
  echo $?
• Loop over array to curl:
  echo -e '27037\n80709\n80730\n80710\n80731' | xargs -I % curl -s -H "PRIVATE-TOKEN: my_token" "https://gitlab.com/api/v4/groups/%/projects" | jq '.[].id' | xargs -I % my_command
• Recover multiple fields with jq:
  jq -r '.[] | [.id, .name]'