git branch on terminal prompt

gistfile1.bash

# Add current git branch (if applicale) to the terminal prompt.
function pgb {
  ref=$(/usr/bin/git symbolic-ref HEAD 2> /dev/null) || return
  dirty=""
  untracked=""

   # Disallow unstaged changes in the working tree
  if ! /usr/bin/git diff-files --quiet --ignore-submodules --
  then
    dirty="*"
  fi

  # Disallow uncommitted changes in the index
  if ! /usr/bin/git diff-index --cached --quiet HEAD --ignore-submodules --
  then
    dirty="*"
  fi

  status=`/usr/bin/git status --porcelain 2>/dev/null| grep "^??" | wc -l`
  if [ $status -gt 0 ]; then
    untracked="+"
  fi

  echo " ("${ref#refs/heads/}"$dirty$untracked)"
}

PS1="${PS1/\\$/\$(pgb)\\$}"