while循环

while 循环输出 1-10

#!/bin/bash
i=1
while [ $i -le 10 ]
do
    echo $i
     let i++
done

while死循环判断

while true
do
     read -p "请输入yes退出:" key
     if [ $key == yes ]
         then 
                break 
    fi
done 
echo "正常退出"

批量添加用户

i=0
while [ $i -le 10 ]
do
     let i++
     useradd stu$i
     echo "passwd" |passwd --stdin stu$i &>/dev/null
     echo stu$i
 done

猜数字

#!/bin/bash 
A=`expr $RANDOM % 1000`
echo "猜数字游戏，请输入1~999的数字"
read -p "请输入所猜的数字:" num
while [ $num -le 999 ] && [ $num -gt 1 ]
do
      let i++
      if [ $num -eq $A ] 
      then 
             echo "输入正确"
             echo "输入次数为$I"
      elif  [ $num -lt $A ]
      then 
             echo "请输入大于所猜的数字"
             read -p "请输入所猜的数字:" num
      else
             echo "请输入小于所猜的数字"
             read -p "请输入所猜的数字:" num
      fi
done      

随机数字字母

echo $RANDOM |md5sum |cut -c 1-10