zsh hooks to growl completion of long-running commands

gistfile1.bash

# long-running command growler
# hooks for zsh, built on bash version at http://hints.macworld.com/article.php?story=20071009124425468

preexec_functions+='save_preexec_time'
save_preexec_time() {
  export PREEXEC_CMD="$(history $HISTCMD | sed 's/ *[0-9]* *//')"
  export PREEXEC_TIME=$(date +'%s')
}

precmd_functions+='growl_about_long_running_commands'
growl_about_long_running_commands() {  
  exitstatus=$?
  if [ $exitstatus -eq 0 ]; then
    img="$HOME/.zsh/images/pass.png"
  else
    img="$HOME/.zsh/images/fail.png"
  fi
  
  stop=$(date +'%s')
  start=${PREEXEC_TIME:-$stop}
  let elapsed=$stop-$start
  max=${PREEXEC_MAX:-10}

  if [ $elapsed -gt $max ]; then
    growlnotify -H localhost --image="$img" -n "LongRunningCommandGrowler" -m "exited with status $exitstatus after $elapsed secs" ${PREEXEC_CMD:-Some command}
  fi
  PREEXEC_TIME=
  PREEXEC_CMD=
}

How do you install this, exactly?

adding this to oh-my-zsh would be awesome

You should be able to put this anywhere in the files that are loaded by zsh and have it picked up. I use a weird loading system that I picked up from someone before oh-my-zsh came around, so I don't really know how OMZ works.