在linux中编写一小段脚本程序

要求:(bash环境)

像一个登录界面一样,先出现一些提示语,然后提示用户输入用户名,再要求输入正确密码才能进行下一步的操作.比如像下面的顺序一样..

肯请高手赐教!!

#!/bin/sh
#随便写的，有不对之处还请指正

tries=0
MAXTIMES=3
stty_orig=`stty -g`

echo -e "WELCOME!\n"
while [ $tries -lt $MAXTIMES ]
do
echo -n "LOGIN NAME:"
USER=`head -n1`
stty -echo
echo -n "PASSWORD:"
LOGINPASS=`head -n1`
if printf "%s\0" "$LOGINPASS"|/sbin/unix_chkpwd "$USER" nullok; then
stty $stty_orig
break
fi
stty $stty_orig
tries=$(($tries + 1))
echo -e "\nLOGIN INCORRENCT\n\n"
done

if [ $tries -ge $MAXTIMES ];then
echo -e "LOGIN FAILED!\n"
exit 1
fi

echo -e "\nLOGIN SUCCESSED\n"
echo -e "go on working!\n"