GNOME Terminal: custom title

set-title.sh

set-title() {
  # Lazy-capture original PS1 on first use
  if [[ -z "${_SET_TITLE_ORIG_PS1+x}" ]]; then
    _SET_TITLE_ORIG_PS1="$PS1"
  fi

  if [[ "$1" == "--clear" ]]; then
    PS1="$_SET_TITLE_ORIG_PS1"
  elif [[ -z "$1" || "$1" == --* ]]; then
    echo "Usage: set-title \"Your Custom Title\""
    echo "       set-title --clear"
    return 1
  else
    # Strip existing title sequence (\[\e]0;...\a\]) from the original PS1,
    # otherwise it would run after ours and overwrite the custom title.
    local base_ps1="${_SET_TITLE_ORIG_PS1#*\\a\\]}"
    PS1="\[\e]0;$1\a\]${base_ps1}"
  fi
}