Ten Bash Productivity Tips for Command-Line Efficiency

I enjoy exploring the Bash environment, and after repeatedly solving the same problems I created a set of reusable functions and added them to my .bashrc to improve command‑line efficiency.

Tip 1 – Add a line to the top of a file

sed -i '1s/^/line to insert
/' path/to/file/you/want/to/change.txt

Tip 2 – Insert multiple lines into a configuration file

cat >> path/to/file/to/append-to.txt << "EOF"
export PATH=$HOME/jdk1.8.0_31/bin:$PATH
export JAVA_HOME=$HOME/jdk1.8.0_31/
EOF

Tip 3 – Recursive search and replace in a directory

Using find together with sed you can replace text across many files:

# OSX version
find . -type f -name '*.txt' -exec sed -i '' s/this/that/g {} +

I wrapped this into a function:

function sr {
  find . -type f -exec sed -i '' s/$1/$2/g {} +
}

Usage: sr wrong_word correct_word Tip 4 – Open a temporary file in Vim/Dropbox

function sc {
  gvim ~/Dropbox/$(openssl rand -base64 10 | tr -dc 'a-zA-Z').txt
}
function scratch {
  gvim ~/Dropbox/$(openssl rand -base64 10 | tr -dc 'a-zA-Z').txt
}

Running sc or scratch opens a new Vim window with a randomly‑named temporary file.

Tip 5 – Download files with curl handling redirects and SSL issues

curl -Lks <some-url>          # download page to terminal
curl -OLks <some-url/to/a/file.tar.gz>  # download a file

Tip 6 – Bashmarks for directory shortcuts

# Save current directory as a bookmark
function s {
  cat ~/.sdirs | grep -v "export DIR_$1=" > ~/.sdirs1
  mv ~/.sdirs1 ~/.sdirs
  echo "export DIR_$1=$PWD" >> ~/.sdirs
}
# Jump to a bookmark
function g {
  source ~/.sdirs
  cd $(eval $(echo echo $(echo $DIR_$1)))
}
# List all bookmarks
function l { source ~/.sdirs; env | grep "^DIR_" | cut -c5-; }
# Completion support omitted for brevity

Tip 7 – Extract a column from formatted output (awk)

function col {
  awk -v col=$1 '{print $col}'
}

Example: git status -s | col 2 prints only the file names.

Tip 8 – Skip the first N words of a line

function skip {
  n=$(($1 + 1))
  cut -d' ' -f$n-
}

Used together with other commands, e.g., docker images | col 3 | xargs | skip 1 to remove the header.

Tip 9 – Create a custom command package

function dur {
  case $1 in
    clone|cl) git clone [email protected]:nicolapaolucci/$2.git ;;
    move|mv) git remote add bitbucket [email protected]:nicolapaolucci/$(basename $(pwd)).git ; git push --all bitbucket ;;
    trackall|tr) for remote in $(git branch -r | grep -v master ); do git checkout --track $remote ; done ;;
    key|k) ssh $2 'mkdir -p .ssh && cat >> .ssh/authorized_keys' < ~/.ssh/id_rsa.pub ;;
    fun|f) typeset -F | col 3 | grep -v _ | xargs | fold -sw 60 ;;
    def|d) typeset -f $2 ;;
    *) echo "[dur]dn shell automation tools"; echo "commands available:"; echo " [cl]one, [mv|move]"; echo " [f]fun lists all bash functions defined in .bashrc"; echo " [def] <fun> lists definition of function defined in .bashrc"; echo " [k]ey <host> copies ssh key to target host"; echo " [tr]ackall], [h]elp";;
  esac
}

These functions illustrate how Bash can be extended to automate common development tasks.