实验12.

case语句

[root@web1 ~]# vim 大哥是个apple

case $1 in

        apple)

        echo banana

        ;;

        banana)

        echo apple

        ;;

        *)

        echo error

esac

测试：

[root@web1 ~]# sh 大哥是个apple apple

banana

[root@web1 ~]# sh 大哥是个apple banana

apple

[root@web1 ~]# sh 大哥是个apple yz

error

实验13.

expect自动应答脚本（输入ip和密码，制动远程连接主机）

[root@web1 ~]# yum install expect -y

Loaded plugins: langpacks

rhel_dvd                                                 | 4.1 kB     00:00     

Resolving Dependencies

.....

[root@web1 mnt]# vim ty16.exp

#!/usr/bin/expect

set IP [ lindex $argv 0 ]

set PASS [ lindex $argv 1 ]

spawn ssh root@$IP

expect {

        "yes/no"

        {send "yes\r";exp_continue}

        "password:"

        {send "$PASS\r"}

        }

interact

[root@web1 mnt]# /mnt/ty16.exp 172.25.254.118 redhat

spawn ssh root@172.25.254.118

The authenticity of host ‘172.25.254.118 (172.25.254.118)‘ can‘t be established.

ECDSA key fingerprint is eb:24:0e:07:96:26:b1:04:c2:37:0c:78:2d:bc:b0:08.

Are you sure you want to continue connecting (yes/no)? yes

Warning: Permanently added ‘172.25.254.118‘ (ECDSA) to the list of known hosts.

root@172.25.254.118‘s password:

Last login: Wed Dec 14 21:58:09 2016 from 172.25.254.18

[root@server18 ~]# ifconfig

eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500

        inet 172.25.254.118  netmask 255.255.255.0  broadcast 172.25.254.255

        inet6 fe80::5054:ff:fe00:120b  prefixlen 64  scopeid 0x20<link>

        ether 52:54:00:00:12:0b  txqueuelen 1000  (Ethernet)

        RX packets 16575  bytes 1458237 (1.3 MiB)

        RX errors 0  dropped 0  overruns 0  frame 0

        TX packets 9690  bytes 1204275 (1.1 MiB)

        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

实验14.

教室11-25主机开着的显示主机名，未开就显示关闭

[root@web1 mnt]# vim ty16.exp

#!/usr/bin/expect

set timeout 2

set IP [ lindex $argv 0 ]

set PASS [ lindex $argv 1 ]

set COMM [ lindex $argv 2 ]

spawn ssh root@$IP $COMM

expect {

        "yes/no"

        {send "yes\r";exp_continue}

        "password:"

        {send "$PASS\r"}

        {send "$COMM\r"}

        }

expect eof

[root@web1 mnt]# vim ty17.sh

#!/bin/bash

for NUM in {17..21}

do

ping -c1 -w1 172.25.254.$NUM &> /dev/null && (

        /mnt/ty16.exp 172.25.254.$NUM westos hostname | grep -E "spawn|root|denied" -v )

done

[root@web1 mnt]# sh ty17.sh

foundation20.ilt.example.com

实验15.

用户的密码匹配实验

[root@web1 mnt]# vim ty20.sh

#!/bin/bash

if

[ -n "$1" -a -n "$2" ]

then

        if

        [ -e "$1" -a -e "$2" ]

        then

        MAXUSER=`wc -l $1 | cut -d " " -f 1`

        MAXPASS=`wc -l $2 | cut -d " " -f 1`

                if

                [ "$MAXUSER" -eq "$MAXPASS" ]

                then

                for NUM in $( seq 1 $MAXUSER )

                do

                USERNAME=`sed -n ${NUM}p $1`

                PASSWORD=`sed -n ${NUM}p $2`

                CKUSER=`getent passwd $USERNAME`

                [ -z "$CKUSER" ]&&(

                useradd $USERNAME

                echo $PASSWORD | passwd --stdin $USERNAME

                )||echo "$USERNAME exist !!"

       done

                else

                echo $1 and $2 have different lines

                fi

        elif

        [ ! -e "$1" ]

        then

        echo "ERROR:$1 is not exist"

        else

        echo "ERROR:$2 is not exist"

        fi

else

echo "ERROR:Please input userfile and password file after command !!"

fi

[root@web1 mnt]# sh ty20.sh  userfile passfile

Changing password for user westos.

passwd: all authentication tokens updated successfully.

Changing password for user redhat.

passwd: all authentication tokens updated successfully.

yz exist !!

##引用##

引用有三种类型

1.弱引用

将字符串放置在双引号中，保留字符串中所有字符的文字值，$、`、\和！字符除外。

echo "can I have a $FRUIT"

echo "the current time is $(date+%)."

2.强引用

将字符串放置在单引号中，保留字符串中所有字符的文字值，同时禁用所有扩展。

echo "make$$$Fast"

rm‘untitled folder‘

3.转义

非引用的\是转义字符。它保留了下一个字符的文字值。如\$PATH是确切的字符串$PATH,而不是PATH变量的内容

echo make\$\$\$Fast\!

ls untitled\folder

##shell变量##

若要定义或 指定值：

FRUIT=apple

若要参考或使用变量：

$FRUIT

${FRUIT}

test 和中括号的作用一样

-z为空

-n不为空

本文出自 “12288655” 博客，谢绝转载！

shell2