unicorn init.d script with rvm on ubuntu 11.04

unicorn

#!/bin/bash
### BEGIN INIT INFO
# Provides:          APPLICATION
# Required-Start:    $all
# Required-Stop:     $network $local_fs $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Start the APPLICATION unicorns at boot
# Description:       Enable APPLICATION at boot time.
### END INIT INFO
#
# Use this as a basis for your own Unicorn init script.
# Change APPLICATION to match your app.
# Make sure that all paths are correct.

#set -u
set -e

# Change these to match your app:
RAILS_ROOT="/home/www/my_server"
PID="$RAILS_ROOT/tmp/pids/unicorn.pid"
OLD_PID="$PID.oldpid"
ENV=production

UNICORN_OPTS="-D -E $ENV -c $RAILS_ROOT/config/unicorn.conf"
CMD="/home/www/my_server/unicorn_rails_wrapper $UNICORN_OPTS"

cd $RAILS_ROOT || exit 1

sig () {
    test -s "$PID" && kill -$1 `cat $PID`
}

oldsig () {
    test -s $OLD_PID && kill -$1 `cat $OLD_PID`
}

case $1 in
start)
    sig 0 && echo >&2 "Already running" && exit 0
    echo "Starting"
    $CMD
    ;;
stop)
    sig QUIT && echo "Stopping" && exit 0
    echo >&2 "Not running"
    ;;
force-stop)
    sig TERM && echo "Forcing a stop" && exit 0
    echo >&2 "Not running"
    ;;
restart|reload)
    #sig USR2 && sleep 5 && oldsig QUIT && echo "Killing old master" `cat $OLD_PID` && exit 0
    sig USR2 && echo reloaded OK && exit 0
    echo >&2 "Couldn't reload, starting '$CMD' instead"
    $CMD
    ;;
upgrade)
    sig USR2 && echo Upgraded && exit 0
    echo >&2 "Couldn't upgrade, starting '$CMD' instead"
    $CMD
    ;;
rotate)
    sig USR1 && echo rotated logs OK && exit 0
    echo >&2 "Couldn't rotate logs" && exit 1
    ;;
*)
    echo >&2 "Usage: $0 <start|stop|restart|upgrade|rotate|force-stop>"
    exit 1
    ;;
esac

what is about unicorn_rails_wrapper ? thx