How to write an IRC bot in bash, redux

irc.sh

#!/bin/bash
exec 3<>/dev/tcp/irc.uriirc.org/16667
echo USER yurumechan yurumechan yurumechan \* >&3
echo NICK yurumechan >&3
while read T C F; do
  echo $T $C $F
	case $(echo $C | tr a-z A-Z) in
	PING)
		echo PONG $F >&3;;
	001)
		echo JOIN \#jubeater >&3;;
	PRIVMSG)
		if echo $F | grep -q yurumechan; then
			echo PRIVMSG \#jubeater :Yurume-chan desu! >&3
		fi;;
	esac
done <&3