工作环境：Red Hat Enterprise Linux Server release 6.5 (Santiago) 、 bash

#!/bin/bash
#
for i in `seq -w 1 10`
do
echo "user$i添加成功"
read -s -p "input passwd:" pass
while [ ${#pass} -lt 6 ]
do
echo ""
read -s -p "input passwd error ,the number of passwd must bigger than 6:" pass
((count++))
if [ $count -gt 3 ];then
echo "f**k you "
exit
fi
done
echo "$pass"
read -p "want to del the user (yes/no):" choice
[ $choice == "yes" -o $choice == "y" ] && echo "del start"
[ $choice == "no" -o $choice == "n" ] && echo "don't del"
[ $choice != ^yes -o $choice != ^no ] && echo "please input (yes/no)!!!"
done

注意：只是简单的示例，并不会添加和删除用户