基础脚本

1.打印九九乘法口诀

1 for i in `seq 9` ;do
2     for j in `seq 9` ;do
3         if [ $i -ge $j ];then
4             let sum=${i}*${j}
5             echo -e "${i}x${j}=$sum\t\c"
6         fi 
7     done
8     echo
9 done

2.检查磁盘空间，一旦发现任何分区利用率高于80%，就发出警报

 1 disk=`fdisk -l | egrep -o "^/dev/[[:alpha:]]+[0-9]"` 
 2 #disk=`lsblk | sed -rn "s/^├─([[:alpha:]]{3}[1-9]).*/\1/p"`
 3 max_num=0
 4 
 5 for name in `echo $disk`;do
 6      #有可能是交换空间，df命令就没有显示。直接跳过
 7     if ! df | egrep -o "^$name.*" &> /dev/null;then
 8         continue
 9     fi
10      #获取使用空间和inodes
11     num=`df | egrep -o "$name.*" | tr -s " " "%" | cut -d "%" -f 5`
12     inodes_num=`df -i | egrep -o "$name.*" | tr -s " " "%" | cut -d "%" -f 5`
13     #使用空间和inodes大于80就发出警告。
14     if [ $num -ge 80 -o $inodes_num -ge 80 ];then
15         if [ $num -gt $max_num ];then
16             max_num=$num
17             max_name=$name
18             max_inodes_num=$inodes_num
19  
20         elif [ $num -eq $max_num ];then
21             max_equal_num=$num
22             max_equal_name=$name
23             max_equal_inodes_num=$inodes_num
24         fi
25      fi
26 done
27 #判断是否有超过80的
28 if [ $max_num -ne 0 ];then
29     let remaining=100-$max_num
30     let inodes_remaining=100-$max_inodes_num
31 
32     #判断是否有两个分区使用量一样
33     if [ -z $max_equal_num ];then
34         wall the $max_name disk is about to run out, only the remaining disk is ${remaining}% and inodes${inodes_remaining}%
35     else
36     wall the $max_name and $max_equal_name disk is about to run out, only the remaining disk is ${remaining}% and inodes${inodes_remaining}%
37     fi
38 fi 

3.打印国际象棋

 1 for j in `seq 8`;do
 2     if [ $[$j%2] -eq 0 ];then
 3         for i in `seq 4`;do
 4             echo -e "\e[41m \e[0m\e[43m \e[0m\c"
 5         done
 6     else
 7          for i in `seq 4`;do
 8             echo -e "\e[43m \e[0m\e[41m \e[0m\c"
 9         done
10     fi
11     echo
12 done

4.生成十个随机数，并进行比较

 1 cat /dev/null > /tmp/suiji.txt
 2 
 3 for i in {1..10};do
 4     echo $random >> /tmp/suiji.txt
 5 done
 6 
 7 max=`cat /tmp/suiji.txt | sort -n | tail -n 1`
 8 min=`cat /tmp/suiji.txt | sort -n | head -n 1`
 9 
10 echo all random is `cat /tmp/suiji.txt | xargs`
11 echo max is $max
12 echo min is $min
13 
14 rm -rf /tmp/suiji.txt

5.后续六个字符串： efbaf275cd、 4be9c40b8b、 44b2395c46、 f8c8873ce0、 b902c16c8b、 ad865d2f63是通过对随机数变量random随机 执行命令： echo $random|md5sum|cut –c1-10 后的结果，请破解这些 字符串对应的random值

 1 for char in efbaf275cd 4be9c40b8b 44b2395c46 f8c8873ce0 b902c16c8b ad865d2f63;do
 2  
 3     for num in `seq 32767`;do
 4         k=`echo ${num} | md5sum | cut -c 1-10`
 5         if [ $k == $char ];then
 6             echo $num
 7             break 
 8         fi
 9     done
10 done

 

6.在/testdir目录下创建10个html文件,文件名格式为数字n（从1到10）加随机8个字 母，如： 1abcdefgh.html

for i in `seq 10`;do
    #生成8个字母
    name=`openssl rand -base64 20 | grep -o "[[:alpha:]]" | head -n 8 | xargs | tr -d " "`
    #控制数字1~10
    while true;do
         num=$[$random%11]
         if [ $num -ne 0 ];then
            break
         fi
    done
    #创建文件
    touch /testdir/$num$name.html
done

 

7.添加10个用户user1-user10，密码为8位随机字符

1 for user in `echo test{1..10}`;do
2  
3     id $user &> /dev/null && echo "$user exist" && continue
4     useradd $user
5     pass=`openssl rand -base64 12 | cut -c 1-10`
6     echo $pass | passwd --stdin $user &> /dev/null
7     echo -e "user:$user\npasswd:$pass"
8  
9 done

 

8.计算100以内所有能被3整除的整数之和

1 sum=0
2 for num in `seq 100`;do
3      if [ $[$num%3] -eq 0 ];then
4         let sum+=$num
5     fi
6 done
7 echo "sum=$sum"

 

9.编写脚本，提示输入正整数n的值，计算1+2+…+n的总和

1 read -p "please enter 1 to add to? : " n
2 sum=0
3  
4 for num in `eval seq $n`;do
5     let sum+=$num
6 done
7  
8 echo "sum=$sum"

 

10.判断/var/目录下所有文件的类型

 1 read -p "please enter the directory to be judged: " dir
 2  
 3 if [[ "`echo $dir | sed -rn "s/^.*(.)$/\1/p"`" != "/" ]];then
 4     if [[ ! -f $dir ]];then
 5         dir=$dir/
 6     else
 7         echo -e "\e[31mplease enter the directory\e[0m"
 8         exit
 9     fi
10 fi
11  
12 for file in `ls $dir`;do
13     if [[ -f $dir$file ]];then
14         echo "$file is file"
15     elif [[ -d $dir$file ]];then
16         echo "$file is direction"
17     elif [[ -c $dir$file ]];then
18         echo "$file is character"
19     elif [[ -l $dir$file ]];then
20         echo "$file is link"
21     else 
22         echo "unknown type"
23     fi
24 done

11.生成0-10的一个数，猜数字

 1 i=$[$random%11]
 2 while true;do
 3     read -p "please enter a lucky number(0-10): " num
 4 
 5     if [ $i -eq $num ];then
 6         echo "congratulations, you guessed it."
 7         exit
 8     elif [ $num -lt $i ];then
 9         echo -e "sorry, the input is too small.\n"
10     else
11         echo -e "sorry, the input is too big.\n"
12     fi 
13 done

 

12.编写脚本，提示请输入网络地址，如192.168.0.0，判断输入的网段中主机在线状态

 1 read -p "enter the ip address segment to be detected. such as 192.168.100.0: " ip
 2 net=`echo $ip | sed -nr "s/^(([0-9]{1,3}\.){3}).*/\1/p"`
 3  
 4 if [[ -z $net ]];then
 5     echo -e "\e[31mplease enter a reasonable ip address\e[0m"
 6     exit
 7 fi
 8  
 9 echo -e "\nstart detection at `date` o'clocki" >> /data/host_up.log
10 echo -e "\nstart detection at `date` o'clocki" >> /data/host_down.log
11  
12 i=1
13 while [ $i -le 10 ];do
14     if ping -c 1 -w 1 $net$i &> /dev/null;then
15         echo $net$i is up >> /data/host_up.log
16     else
17         echo $net$i is down >> /data/host_down.log
18      fi
19     let i++
20 done

 

13.每隔3秒钟到系统上获取已经登录的用户的信息；如果发现用户登录， 则将登录时间和主机记录于日志/data/login.log中,并退出脚本

1 read -p "input needs to monitor users: " user
2 while true ; do
3     if who | grep "^$user" > /dev/null ;then
4         echo "$user is logging in at `date '+%f %t'`" >> /data/login.log
5         exit
6     fi
7     sleep 3
8 done 

 

14.用二个以上的数字为参数，显示其中的最大值和最小值

 1 for((i=1;i<=10;i++));do
 2  
 3     read -p "enter the number to compare(enter end input): " num_$i
 4     val=`eval echo '$'num_$i`
 5  
 6     if [[ -z $val ]];th 
 7         break
 8     fi
 9  
10     [ $i -eq 1 ] && max=$val
11     [ $i -eq 2 ] && min=$val
12  
13     if [ $max -le $val ];then
14         max=$val
15     fi
16 
17     [ $i -ge 2 ] && if [ $min -ge $val ];then min=$val ;fi
18 done
19  
20 echo "max=$max;min=$min"

 

15.求100以内所有正奇数之和

 1 odd_num=0
 2 even_num=0
 3  
 4 i=1
 5 while [ $i -le 100 ];do
 6     if [ $[$i%2] -eq 0 ];then 
 7         let even_num+=i
 8     else
 9         let odd_num+=i
10     fi
11     let i++
12 done
13  
14 echo odd number is $odd_num
15 echo even is $even_num

 

16.判断用户输入的参数是否为正整数

 1 read -p "please enter a positive integer: " num
 2 if [[ "$num" =~ ^[0-9]+$ ]];then
 3     if [ $num -gt 0 ];then
 4         echo "you are entering a positive integer."
 5     else
 6         echo "0 is not a positive integer"
 7     fi
 8 else
 9     echo "you are not entering a positive integer"
10 fi

 

17./etc/rc.d/rc3.d目录下分别有多个以k开头和以s开头的文件；分别读取每个文件，以k开头的输出为文件加stop，以s开头的输出为文件名加start，如k34filename stop s66filename start

1 for file in `ls /etc/rc.d/rc3.d/`;do
2  
3     if echo $file | sed -rn "s/^(s.*)$/\1/";then
4         echo "$file start"
5     elif echo $file | sed -rn "s/^(k.*)$/\1/";then
6         echo "$file stop"
7     fi
8  
9 done

 

18.用文件名做为参数，显示其中的最大值和最小值

 1 file=1
 2 until [[ "$file" == "0" ]];do
 3     read -p "please enter the file to be counted(0 exit script): " file
 4  
 5     if [[ -f $file ]];then
 6         echo -e "$file the total number of lines is `wc -l < $file`\n"
 7         elif [[ "$file" != "0" ]];then
 8         echo -e "$file not file\n"
 9     fi
10  
11 done

 

19.打印等腰三角形

 1 read -p "please enter the height: " high
 2 for row in `seq $high`;do
 3     let num_1=$high-$row
 4     let num_2=2*$row-1
 5 
 6     for space in `seq $num_1`;do
 7         echo -e " \c"
 8     done
 9  
10     for star in `seq $num_2`;do
11         echo -e "*\c"
12     done
13  
14     echo
15 done

 

20.编写脚本/root/bin/yesorno.sh，提示用户输入yes或no,并判断用户输入的是yes还是no,或是其它信息

1 read -p "please enter yes or no: " input
2  
3 if [[ "$input" =~ [yy]([ee][ss]){,1} ]];then
4     echo "your choice is yes"
5 elif [[ "$input" =~ [nn]([oo]]){,1} ]];then22:45:12
6     echo "your choice is no"
7 else
8     echo "your choice is neither yes nor no"
9 fi