Command-Line Hacks

shell.md

Useful shell snippets

Change Extension

change .doc to .txt (for whatever reason)

for name in *.doc
do
  mv "$name" "${name%.doc}.txt"
done

Fixed-Width CSV

Align CSV entries to view in a terminal.

$ cat << EOF | awk -F"," '{printf "%10s %-10s\n", $1, $2}' 
111,AAA
22222,BBBBB
EOF

Result:
      111 AAA
    22222 BBBBB

Loop in shell

for i in `seq 1 99`
do
  echo "ahh!"
done

tar options

list file in tar.gz

gunzip -c xyz.tar.gz | tar vtf -

extract one file in tar.gz

gunzip -c xyz.tar.gz | tar xf - -I filename