demo1 (输入/输出)
1.1. target :
输入姓、名， 输出姓名
1.2. create directory
mkdir ~/bin
1.3. create & edit sheel script
vim fullname.sh
note: more comment is useful
#!/bin/bash #Program # User inputs his first name and last name . Program shows his full name. #History : #2017/04/10 logan First lease PATH=/bin:$PATH #将当前目录加入系统环境 export PATH read -p "Please input your firstname:" firstname read -p "Please input your lastname:" lastname echo -e " Your full name is :" ${firstname} ${lastname}
1.4. run
[rocky@localhost bin]$ sh fullname.sh
demo2 (计算PI)
2.1 target
输入小数点后位数 输出PI
2.2 create & edit
vim cal_pi.sh
#!/bin/bash #Program: # Usre input a scale number to calculate pi number. #History: #2017/04/10 logan First lease PATH=/bin:PATH export PATH echo -e "This program will calculate pi value. " echo -e "You should input a float number to calculate pi value. " read -p "This scale number (10-10000) ? " checking num=${checking:-"10"} echo -e "Starting calculate pi value. Be patient." time echo "scale=${num}; 4*a(1)"|bc -lq
2.3 run
输入 5
输出 3.14156
demo3 ($# $@ $* 的使用)
3.1 target
输入参数， 显示相关结果
3.2 create & edit sheel
vim how_paras.sh
#!/bin/bash #Program: # Program shows the script name, parameters #History: #2017/04/11 logan First release PATH=/bin:$PATH export PATH echo "The script name is ==> ${0}" echo "Total parameter number is ==> $#" [ "$#" -lt 2 ] && echo "The number of parameter is less than 2. Stop here." && eexit 0 echo "Your whole parameter is ==> '$@'" echo "The 1st parameter ==> ${1}" echo "The 2nd parameter ==> ${2}"
3.3 run
[logan@localhost bin]$ sh how_paras.sh zhang li wang
The script name is ==> how_paras.sh
Total parameter number is ==> 3
Your whole parameter is ==> 'zhang li wang'
The 1st parameter ==> zhang
The 2nd parameter ==> li
demo4 (shift 使用)
4.1 vim how_shift.sh
.....#省略注释 PATH...... echo "The script name is ==> ${0}" echo "Total parameter number is ==> $#" [ "$#" -lt 6 ] && echo "The number of parameter is less than 6. Stop here." && eexit 0 echo "Your whole parameter is ==> '$@'" shift echo "------------------shift one--------" echo "Total parameter number is ==>$#" echo "The whole parameter is $@" shift 3 echo "------------------shift three------" echo "Total parameter number is ==>$#" echo "the whole parameter is ==> $@"
4.2 run
[logan@localhost bin]$ sh how_shift.sh one two three four five six
The script name is ==> how_paras.sh
Total parameter number is ==> 6
Your whole parameter is ==> 'one two three four five six'
------------------shift one--------
Total parameter number is ==>5
The whole parameter is two three four five six
------------------shift three------
Total parameter number is ==>2
the whole parameter is ==> five six
[logan@localhost bin]$ vim how_paras.sh
demo5 (if 条件判断式)
5.1 vim if_fi.sh
#!/bin/bash #Program: # This program shows the user's choice #History: #20170411 logan first release PATH=/bin:$PATH export PATH read -p "Please input (Y/N): " yn if [ "${yn}" == "Y" ] || [ "${yn}" == "y" ];then echo "OK, continue" exit 0 fi if [ "${yn}" == "N" ] || [ "${yn}" == "n" ];then echo "Oh, interrupt!" exit 0 fi echo "I don't know what your choice is" && exit 0
note: 中括号内 变量及字符两边需要空格符，否则报错 '找不到命令'
5.2 run
sh if_fi.sh
demo6 (日期计算)
6.1 vim cal_retired.sh
#!/bin/bash #Program: # You input your demobilization date, I calculate how many days before you demobilize. #History: #2017/04/12 logan first release PATH=/bin:$PATH export PATH #1. tell user the function of the shell script, and the format of the date echo "This program will try to calculate:" echo "How many days before your demobilization date..." read -p "Please input your demobilization date (YYYYMMDD ex>20131230): " date2 #2. test the comment you just input with the Pattern date_d=$(echo ${date2} |grep '[0-9]{8}') # check length whether 8 of the input num if [ "${date_d}" == "" ];then echo "You input the wrong date format...." exit 1 fi #3. begin to calculate the date declare -i date_dem=$(date --date="${date2}" +%s) #seconds count of the input date declare -i date_now=$(date +%s) #seconds count date now declare -i date_total_s=$((${date_dem}-${date_now})) #differ from the two date declare -i date_d=$((${date_total_s}/60/60/24)) #transfer to days if [ "${date_total_s}" -lt "0" ];then echo "You had been demobization before: " $((-1*${date_d})) " days ago" else declare -i date_h=$(($((${date_total_s}-${date_d}*60*60*24))/60/60)) echo "You will demobilize after ${date_d} days and ${date_h} hours." fi
6.2 run
sh cal_retired.sh
demo7 (case..esac)
7.1 vim hello-3.sh
#!/bin/bash #Program: # Show "Hello" from $1.... by using case .... esac #History: #2017/04/12 logan First lease PATH=/bin:$PATH export PATH case ${1} in "hello") echo "Hello, how are you?" ;; "") echo "You MUST input parameters, ex> {${0} someword}" ;; *) echo "Usage ${0} {hello}" ;; esac
7.2 run
sh hello-3.sh
demo8 (function使用)
vim demo.sh
#!/bin/bash #Program: # Show "one two three" from $1.... by using case .... esac #History: #2017/04/12 logan First lease PATH=/bin:$PATH export PATH function printit(){ echo -n "Your choice is " #-n means not enter to next line } case ${1} in "one") printit; echo ${1} | tr 'a-z' 'A-Z' #transfer to Upper ;; "two") printit; echo ${1} | tr 'a-z' 'A-Z' #transfer to Upper ;; "three") printit; echo ${1} | tr 'a-z' 'A-Z' #transfer to Upper ;; *) echo "Usage ${0} {one|two|three}" ;; esac
8.2 run
sh demo.sh one
demo9
9.1 vim while_do_done.sh
#!/bin/bash #Program: # Repeat question until user input correct answer. #History: #2017/04/12 logan first release PATH=/bin:$PATH export PATH while [ "${yn}" != "yes" -a "${yn}" != "YES" ] do read -p "Please input yes/YES to stop this program: " yn done echo "OK! you input the correct answer."
9.2 run
sh while_do_done.sh
demo10
10.1 vim add_1_to_100.sh
#!/bin/bash #Program: # calculate the sum of num 1,2...100 #History: #2017/04/12 logan first release PATH=/bin:$PATH export PATH s=0 i=0 while [ "${i}" != "100" ] do i=$(($i+1)) s=$(($s+i)) done echo "The result of '1+2+3...+100' is ==> $s"
10.2 run
sh add_1_to_100.sh
10.3 vim add_1_to_num.sh
#!/bin/bash #Program: # calculate the sum of num 1,2...100 #History: #2017/04/12 logan first release PATH=/bin:$PATH export PATH s=0 i=0 j=0 while [ "${j}" -le "0" ] do read -p "Please input the num: " j done while [ "${i}" != "${j}" ] do i=$(($i+1)) s=$(($s+i)) done echo "The result of '1+...+ ${j}' is ==> $s"
demo11
11.1 vim for_test.sh
#!/bin/bash PATH=/bin:$PATH export PATH for animal in dog cat elephant do echo "There are ${animal}s..." done
11.2 sh for_test.sh
demo12
12.1 target
ping 局域网内 192.168.1.1~100的看通不通, seq(sequence)指令的使用
12.2 vim pingip.sh
#!/bin/bash #Program # Use ping command to check the network's PC state #History #2017/04/14 logan first release PATH=/bin:$PATH export PATH network="192.168.1" for sitenu in $(seq 1 100) #seq 为 sequence(连续)的缩写 do ping -c 1 -w 1 ${network}.${sitenu} &> /dev/null && result=0 || result=1 if [ "${result}" == 0 ];then echo "Server ${network}.${sitenu} is UP." else echo "Server ${network}.${sitenu} is DOWN." fi done
12.3 run
sh pingip.sh
demo13
13.1 target
判断式(test)的使用
13.2 vim dir_perm.sh
#!/bin/bash #Program # User input dir name, I find the permission of files. #History: #2017/04/14 logan first release PATH=/bin:$PATH export PATH read -p "Please input a directory: " dir if [ "${dir}" == "" -o ! -d "${dir}" ]; then echo "The ${dir} is NOT exist in your system." exit 1 fi filelist=$(ls ${dir}) for filename in ${filelist} do perm="" test -r "${dir}/${filename}" && perm="${perm} readable" test -w "${dir}/${filename}" && perm="${perm} writable" test -x "${dir}/${filename}" && perm="${perm} executable" echo "The file ${dir}/${filename}'s permission is ${perm} " done
13.3 run
sh dir_perm.sh
demo14
14.1 description
for循环的使用
14.2 vim cal_1_nu.sh
#!/bin/bash #Program # Try do calculate 1+2+..+ ${your_input} #History: #2017/04/14 logan first release PATH=/bin:$PATH export PATH read -p "Please input a number, I will count for 1+2..+ your_input:" nu s=0 for (( i=1; i<=${nu}; i=i+1)) do s=$((${s}+${i})) done echo "The result of '1+2+...${nu}' is ==> ${s}"
demo15
15.1 target
随机选择3种菜
15.2 vim what_to_eat3.sh
#!/bin/bash #Program # Try do tell you what you may eat. PATH=/bin:$PATH export PATH eat[1]="zhang san ji" eat[2]="li si ji" eat[3]='wang wu ji' eat[4]="zhang liu ji" eat[5]="qian qi ji" eat[6]="hao 1" eat[7]="hao 2" eat[8]="hao 3" eat[9]="hao 4" num=9 count=0 while [ "${count}" -lt 3 ]; do check=$(( ${RANDOM} * ${num} / 32767 + 1 )) flag=0 if [ "${count}" -ge 1 ];then for i in $(seq 1 ${count} ) do if [ "${selectedNum[$i]}" == $check ];then flag=1 fi done fi if [ ${flag} == 0 ];then echo "You mat eat ${eat[${check}]}" count=$((${count} + 1 )) selectedNum[${count}]=${check} fi done
demo16 (计算生日)
16.1 vim birthday_howlong.sh
#!/bin/bash #Program # how many days your birthday remain #History #2017/04/17 logan first release read -p "Please input your birthday (MMDD, ex>0709): " bir now=`date +%m%d` if [ "$bir" == "$now" ];then echo "Happy birthday to you!!!" elif [ "$bir" -gt "$now" ];then year=`date +%Y` total_d=$(($((`date --date="$year$bir" +%s`-`date +%s`))/60/60/24)) echo "Your birthday will be $total_d later" else year=$((`date +%Y`+1)) total_d=$(($((`date --date="$year$bir" +%s`-`date +%s`))/60/60/24)) echo "Your birthday will be $total_d later" fi
demo17 (show accounts)
17.1 vim show_account.sh
#!/bin/bash accounts=`cat /etc/passwd | cut -d':' -f1` for account in $accounts do declare -i i=$i+1 echo "The $i account is "$account" " done