Advanced shell scripts (for, while, if, case)

1, write script/root/bin/createuser.sh, to achieve the following functions: Use a user name as a parameter, if the user specified parameter exists, it will show its existence, otherwise add, and generate a 8-bit random password and there is a file, the initial prompt to change the password, Displays information such as the ID number of the added user.

#!/bin/bash# ------------------------------------------#  filename: cid.sh # date: 2017-09-16# author: liuke# description:    Use a user name as a parameter, if the specified parameter of the user exists, it will show that it exists, otherwise add #  generate 8 random password and there is a file, the initial prompt to change the password, display the ID number of the added user and other information. # -------------------------------------------read -p  "Please input a username:"  unameid  $uname  &> /dev/nulle=$?if [  $e  -eq 0 ]then     echo  "$uname  is exist"     exit 2else     useradd  $uname     echo  ' cat  /dev/urandom  |  tr -d -c  ' [: alnum:][:p UNCT:] '  | head -c 10 '  > /app/mima     passwd  $uname     id  $unamefiunset  uanme e 

2, write script/root/bin/yesorno.sh, prompt the user to enter Yes or no, and determine whether the user entered Yes or no, or other information

#!/bin/bash#------------------------------------------# Filename:yesno.sh # revision:null# date:2017-09-10# Author: liuke# Description: Prompts the user to enter Yes or no, and to determine whether the user entered Yes or no, or other information #-------------------------------------------read-p "Yue ma Yes or no: "Wordword= ' echo $word |tr" A-Z "" A-Z "' Case $word Inyes|y) echo" Yue ";; No|n) echo "Buyue";; *) echo "error input" Esac

3, write script/root/bin/filetype.sh, judge user input file path, display its file type (normal, directory, link, other file type)

#!/bin/bash#------------------------------------------# Filename:filetype.sh # date:2017-09-11# author:liuke# Description: Determine the user input file path, display its file type #-------------------------------------------read-p "Please input a file:" Fileif [-F $f      Ile];then echo "filetype is common file" elif [-D $file];then echo "filetype is directory" elif [-H $file];then echo "filetype is soft link" else echo "filetype was other" Fiunset file

4, write the script/root/bin/checkint.sh, determine whether the user input parameter is a positive integer

#!/bin/bash#------------------------------------------# Filename:checkint.sh # date:2017-09-11# author:liuke# Description: Determine if the user input parameter is a positive integer #-------------------------------------------read-p "Please input a num:" numif [[$num =~ ^[ 1-9][0-9]*$]];then echo "The num is a positive integer" else echo "wrong input" fi

5. Determine the type of all files in the/var/directory

#!/bin/bash# ------------------------------------------# filename: file-var.sh # date : 2017-09-11# author: liuke# description:  determine the type of all files under the/var/directory # ------------------- -----------------------cd /var/;ls -1 | while read filenamedo     if [ -f  $filename  ];then         echo   "  $filename  filetype is common file"     elif [ -d   $filename  ];then         echo  $filename   Filetype is directory "    elif [ -h  $filename  ];then          echo  "$filename  filetype is soft link "    else         echo " $filename   Filetype is&nbSp;other "    fidone         unset  FileName

6, add 10 user user1-user10, password is 8 bit random characters

#!/bin/bash# ------------------------------------------#  filename: 10user.sh # date: 2017-09-11# author: liuke# description:  Add 10 user User1-user10, password 8-bit random character # -------------------------------------------for  (i=1;i<= 10;i +=1))      do        pw= ' Cat /dev/urandom  |tr -d -c  ' [: alnum:][:p UNCT:] ' |head -c 8 '          useradd  user$i && echo  $PW |passwd --stdin user$i  &> /dev/null        echo -e  "USER:USER$I;PASSWD: $PW "     done# for i in {1..10};d O userdel -r user $i;d one   Delete 10 users at a time 

7. The/ETC/RC.D/RC3.D directory has several files starting with K and beginning with S, respectively reading each file, the output starting with K is the file plus stop, the output starting with S is the filename plus start, such as K34filename stop S66filename Start

#!/bin/bash#------------------------------------------# Filename:rc3.sh # date:2017-09-16# author:liuke# Description: Read/etc/rc.d/rc3.d/Each file separately, the output starting with K is the file plus stop, the output starting with S is the filename plus start#--------------------------------------- ----for filename in ' ls/etc/rc.d/rc3.d/';d ocase $filename ink*) echo "$filename stop";; s*) echo "$filename start" Esacdoneunset filename

8, write the script, prompt to enter the value of positive integer n, calculate the sum of 1+2+...+n

#!/bin/bash#------------------------------------------# filename:1-nhe.sh # date:2017-09-11# author:liuke# Description: Prompts for the value of positive integer n, calculates the sum of 1+2+...+n #-------------------------------------------Read-p "Please input a num:" NUMIF [[ $num =~ ^[1-9][0-9]*$]];then sum=0 for ((i=1;i<= $num; i+=1)) do sum=$ (($sum + $i)) d The sum of one echo "1+2+...+n: $sum" Fiunset num sum

9. Calculates the sum of all integers within 100 that can be divisible by 3

#!/bin/bash#------------------------------------------# Filename:zhengchu3.sh # date:2017-09-11# author:liuke# Description: Calculates the sum of all integers within 100 that can be divisible by 3-------------------------------------------sum=0for ((i=3;i<= 100;i+=3)) do s um=$ (($sum + $i)) done echo "100 The sum of all integers that can be divisible by 3: $sum" unset sum

10, write the script, prompt please enter network address, such as 192.168.0.0, determine the status of the host online in the input network segment.

#!/bin/bash# ------------------------------------------#  filename: scanip11-2.sh # revision: null# date: 2017-09-10# author:  liuke# description:  Prompt Please enter the network address, such as 192.168.0.0, determine the input network segment of the host online status. # -------------------------------------------> /app/ip.txtread -p  "Please input  a ip: " ipecho  $ip |egrep  " ([0-9]|[ 1-9][0-9]|1[0-9]{2}|2[0-4]0-9]|25[0-5]) \.) {3} ([0-9]| [1-9] [0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]) "&> /dev/nullif [ $? -eq 0 ];then      id= ' echo  $ip |egrep -o  ". *\." '      ping -c 1 -w 1  $ip  &> /dev/null      echo  "$ip  is up" >>/app/ip.txt     echo   "$ip  is down" fi 

11. Print 99 multiplication table (for loop)

#!/bin/bash#------------------------------------------# filename:9*9.sh # revision:null# date:2017-09-10# Author:   liuke# Description: Print 99 multiplication table (for loop) #-------------------------------------------for i in {1..9};d o for j in ' seq $i ';d o Echo-en "${i}x${j}=$[$ix $j]\t" Done Echodone

12. Print 99 multiplication table (while loop)

#!/bin/bash#------------------------------------------# filename:9*9while.sh # date:2017-09-11# author:liuke# Description: Print 99 multiplication table (while) #-------------------------------------------while ((i<10,j<9)) do Echo-en "${i}x${ j}=$[$i * $j |bc]\t "done Echo

13, create 10 HTML files in the/testdir directory, the file name format is the number n (from 1 to 10) plus a random 8 letters, such as: 1abcdefgh.html.

#!/bin/bash#------------------------------------------# filename:10user.sh # date:2017-09-11# author:liuke#     Description: Add 10 user user1-user10, password 8-bit random character #-------------------------------------------for ((i=1;i<= 10;i+=1)  Do pw= ' cat/dev/urandom |tr-d-C ' [: alnum:][:p UNCT:] ' |head-c 8 ' useradd user$i && echo $PW |passwd --stdin user$i &>/dev/null echo-e "user:user$i;passwd: $PW" done# for i in {1..10};d o userdel-r user$ I;done Delete 10 users at a time

14, write a script, for 100 of all positive odd sum

#!/bin/bash#------------------------------------------# Filename:jishuhe.sh # date:2017-09-11# author:liuke# Description: Write a script that asks for all positive and odd numbers within 100 and #-------------------------------------------Sum=0;i=1while ((i<100)) do sum=$[$ Sum + $i] Let i=$[$i +2]done echo "100 all positive odd sum: $sum"

15. write a script that generates 10 random numbers using the variable random, outputs the 10 numbers, and displays the maximum and minimum values.

#!/bin/bash# ------------------------------------------# filename: random10-2.sh #  date: 2017-09-16# author: liuke# description:  uses the variable random to generate 10 random numbers, outputting the 10 numbers, and displays the maximum and minimum values #              while#  -------------------------------------------i=1while [  $i  -lt 11 ];d o                 sum= ' Echo $[RANDOM] '                 echo -e   "$sum"   "\c"                  if [  $i  -le 1 ];then                         max= $sum   min= $sum                 elif [[  $sum  -gt  $max  ]];then                         max= $sum                  elif [[  $sum  -lt  $min  ]];then                          min= $sum                  fi                 let i+=1done                 echo                 echo  "the Number max is: $max; Min number is: $min " 

16. Write scripts, edit menus, the user enters a number in the menu list to display the corresponding price.

#!/bin/bash#------------------------------------------# Filename:caidan.sh # date:2017-09-10# author:liuke# Description: Edit menu, user input A number in the menu list, display the corresponding price. #-------------------------------------------echo "1=yangroutang2=mifan3=hulatang 4=jiaozi5=lamian6=huimian" read- P "Please input your choose num:" Numcase $num in1|4) echo "The Price is 20￥";; 2|5) echo "The Price is 12￥";; 3|6) echo "The Price is 10￥";; *) echo "Error Choose" Esac

17, write a script to achieve the printing chess board

#!/bin/bash# ------------------------------------------# filename: chess11.sh # date:  2017-09-11# Author: liuke# Description:  Board # ----------------------------------- --------for  ((i=1;i<=8;i++));d o    for  ((j=1;j<=8;j++));d o        total=$ (($i + $j))       tmp=$ (($total  % 2) )           if [  $tmp  -eq 0 ]                then                     echo  -e -n  "\033[43m  \033[0m"                 else                     echo -e -n  "\033[41m  \033[0m"            fi    done    echodone

This article is from the Linux file system blog, so be sure to keep this source http://13250262.blog.51cto.com/13240262/1966066

Advanced shell scripts (for, while, if, case)