shell實現倒計時功能

#!/bin/bash
##############################################################
# File Name: oldboyedu.sh
# Version: V1.0
# Author: zhang yao
# Organization: www.oldboyedu.com
# Created Time : 2017-06-05 08:29:52
# Description: 
##############################################################

name=oldboy
passWord=123456

echo "Hello World！"
echo "你現在使用$USER用戶登錄，字符集為$LANG，因此我可以使用中文和你交流。"

while true
  do
    read -p "請輸入你的用戶名：" user
    read -s -p "請輸入你的密碼：" pass

    if [ "$user" == "$name" -a "$pass" == "$passWord" ]
      then
        echo "身份認證成功！"
        break
    else
      echo "身份認證失敗，請重試！"
      
      for i in `seq -w 10 -1 1`
        do
          echo -ne "\b\b$i";
          sleep 1;
      done
    fi
done