shell脚本编写

shell语法

summary

编写shell脚本时，需要声明这是一个脚本文件#!/bin/bash
声明作者，和编写日期。
NOTE：尽可能详细的写出脚本的功能，做好注释。shell的可读性不是很好，因此强烈建议编写注释。

Hello World

#!/bin/bash
# this is a annotation
# auto echo hello world!
# by authors nulijiushimeili 2015
echo "hello world!"
echo -e "\033[32mPlease select Menu follow:\033[0m"
echo "1)installing apache server."
echo "2)installing mysql server."
echo "3)installing php server."
echo "4)deploying lamp web goals."
echo -e "\033[32m-----------------------------------------\033[0m"

获得执行的结果信息

当状态码等于0时表示执行成功，否则表示命令执行失败

#!/bin/bash
# 测试一条命令的执行结果
# 2019-02-19

service iptables stop

# 第一种写法，-eq 表示 =
if [ $? -eq 0 ]; then
    echo "success!"
else
    echo "failed!"
fi

# 第二种写法，-ne 表示 !=
if [ $? -ne 0 ]; then
    echo "failed!"
else
    echo "success!"
fi

将命令执行的结果返回给一个变量。

#!/bin/bash
# 得到执行命令的结果

res=`ps -ef | grep mysql-server`
echo $res

变量的使用

#!/bin/bash
# define path variables
name="Tom"
echo "$name"
echo "This is my name $name."
# shell process id.
echo $UID
# shell home
echo $PWD
echo "#######################"
# the first paramiter
echo $0
# the second paramiter
echo $1 $2
echo "#########################"
# expresses shell running ok
echo "The \$? is $?"
# get all parameters
echo "The \$* is $*"
# return how much params 
echo "The \$# is $#"

if 语句

#!/bin/bash
# auto if test
# by author nulijiushimeili 2015

num1=$1
num2=$2
if (($#<2));then
    echo "Usage: if.sh param1 param2."
    echo "wrong input !!!"
else 
    if(($num1>$num2));then
        echo "This $num1 greate $num2 !"
    elif(($num1<$num2));then
        echo "This $num1 little $num2 !"
    else
        echo "The $num1 equals $num2 !"
    fi
fi

# check and mkdir
dir=temp
if [ ! -d $dir ];then
        mkdir -p $dir
        echo "create dir $dir success!"
else
        echo "$dir is exists."
fi

elseif 语句

#!/bin/bash
# if else test demo
# by author nulijiushimeili

scores=$1
if (($#>0));then
    if [[$scores -gt 85]];then
        echo "Very good!";
    elif [[$scores -gt 70]];then
        echo "good";
    elif [[$scores -gt 60]];then
        echo "pass";
    else 
        echo "so bad!";
    fi
else
    echo "Usage: elif.sh param1";
fi

for语句

#!/bin/bash
# test for
# by author nulijiushimeili 2015

# first test
for i in {1..5}
do
    echo $i
done

# second test
for i in 6 7 8 9 10
do
    echo $i
done

# third test
for FILE in $HOME/*
do
    echo $FILE
done

# high order usage
for((i=0;i<10;i++))
do
    echo $i
done

while 语句

#!/bin/bash
# test while loop
# by author nulijiushimeili

# print number from 1 to 5
counter=0
while [ $counter -lt 5 ]
do
    counter=`expr $counter + 1`
    echo $counter
done

# print input number in while loop 
echo "please input a number."
echo "ctrl + d to exit."
while read FILM
do
    echo "Yeah! great film the $FILM"
done

case语句

#!/bin/bash
# test case
# by author nulijiushimeili 2015

#if(($#>0))
if [ $# -gt 0 ]
then
    case $1 in
    1)
        echo "one"
        ;;
    2)
        echo "two"
        ;;
    3)
        echo "three"
        ;;
    4)
        echo "four"
        ;;
    *)
        echo -e "\033[32mNothing to matched.\033[0m"
        ;;  
    esac
else
    echo "Must to input a number parameter."
    echo "please input a number in {1,2,3,4}."
    echo "Usage: case.sh 1"
fi

shell函数

#!/bin/bash
# test function
# by author nulijiushimeili

# 声明一个方法
print(){
    echo "hello word."
}

# 调用方法
print

test(){
    num1=3
    num2=4
    return $(($num1 + $num2))
}

test
result=$?
echo $result

按行读取文件

#!/bin/base
# read file and get each line
# by author nulijiushimeili 2017

# -r express : allow special charactor
while read -r line
do
    echo $line
done </opt/datas/emp.txt


# test add 
i=1
sum=0
while ((i<10))
do
    sum=$((sum=i+$sum))
    i=$[i+1]
done
echo $sum

shell 编程知识

输出带颜色的打印信息

# 输出带颜色的打印信息
echo -e "\033[32m------\033[0m"
# 输出黑底白字的信息
echo -e "\033[40,37m------\033[0m"

字体颜色设置

# 字体颜色设置
echo -e “\033[30m 黑色字 \033[0m”
echo -e “\033[31m 红色字 \033[0m”
echo -e “\033[32m 绿色字 \033[0m”
echo -e “\033[33m 黄色字 \033[0m”
echo -e “\033[34m 蓝色字 \033[0m”
echo -e “\033[35m 紫色字 \033[0m”
echo -e “\033[36m 天蓝字 \033[0m”
echo -e “\033[37m 白色字 \033[0m”

字体底色设置

# 字体底色设置
echo -e “\033[40;37m 黑底白字 \033[0m”
echo -e “\033[41;37m 红底白字 \033[0m”
echo -e “\033[42;37m 绿底白字 \033[0m”
echo -e “\033[43;37m 黄底白字 \033[0m”
echo -e “\033[44;37m 蓝底白字 \033[0m”
echo -e “\033[45;37m 紫底白字 \033[0m”
echo -e “\033[46;37m 天蓝底白字 \033[0m”
echo -e “\033[47;30m 白底黑字 \033[0m”

特殊参数

# 参数
$# 参数的个数
$? shell 脚本运行返回值,OK返回0
$* 所有的参数

$UID 用户id,root的uid=0
$PWD 当前文件夹绝对路径

逻辑运算符解析

# 逻辑运算符解析
-f  判断文件是否存在
-d  判断目录是否存在
-eq 等于,应用于整型数值比较
-ne 不等于,应用于整型数值比较
-lt 小于,应用于整型数值比较
-gt 大于,应用于整型数值比较
-le 小于或等于,应用于整型数值比较
-ge 大于或等于,应用于整型数值比较
-a  双方都成立(and)  condition1 -a condition2
-o  单方成立(or) condition1 -o condition2
-z  空字符串

测试脚本编写是否正确

/bin/bash -n if.sh      # 如果没有输出任何东西表示脚本编写正确

文件IO

# 将结果写入文件，结果不会在控制台展示，而是在文件中，覆盖写
$ echo result > file
# 将结果写入文件，结果不会在控制台展示，而是在文件中，追加写
$ echo result >> file
echo input < file  #获取输入流

一些练习的小例子

自动备份mysql数据库

#!/bin/bash
# auto backup mysql db
# by author nulijiushimeili 2015
# define backup path

bak_dir=/opt/datas/mysql_backup/`date +%Y%m%d`
mysql_db=sqoop
mysql_user=root
mysql_pwd=123456
mysql_cmd=/usr/bin/mysqldump

if [ $UID -ne 0 ]
then
 echo "Must to be use root for exec shell."
 exit
fi

if [ ! -d $bak_dir ]
then
 mkdir -p $bak_dir
 echo -e "\033[32mThe $bak_dir create successfully!\033[0m"
else
 echo "This $bak_dir is exists ..."
fi

# mysql backup cmd.
mysqldump -u$mysql_user -p$mysql_pwd -d $mysql_db >$bak_dir/$mysql_db.sh

if [ $? -eq 0 ]
then
 echo -e "\033[32mThe mysql backup $mysql_db successfully!\033[0m" 
else
 echo -e "\033[32mThe mysql backup $mysql_db failed, please check.\033[0m"
fi

玩具程序：设置环境变量（第一版）

#!/bin/bash
# set env
# by author nulijiushimeili 2017

time=`date +%Y%m%d%H%M%S`
new_profile="profile_$time"

echo $new_profile

if [ $UID -ne 0 ]
then
  echo "Must to be use root to exec shell."
  exit
fi

if [ $1 == "help" ]
      then
          echo "Usage: set-env.sh JAVE_HOME."
          echo "Usage: set-env.sh help for help."
          exit
fi

echo "Are you sure to append this dir to envirement virable?"
echo "input y to continue and copy /etc/profile to $new_profile, the new file will as a backup for /etc/profile, if you want to use the old profile, you can rename the histry profile to 'profile'."
echo "continue to input 'y', and input 'n' for exit.[y|n]?"
read create_file_yes_or_no
if [ $create_file_yes_or_no == "y" ] 
then
  sudo cp /etc/profile /etc/$new_profile
  if [ $? -eq 0 ]
  then
      echo "create new profile success."
      if [ $# -gt 0 ]
      then
          # content=echo "# $1%nexport $1=$PWD%nexport PATH=\$PATH=\$PATH:\$$1/bin"
          sh="export PATH=\$PATH:\$$1/bin"
          home="export $1=$PWD"
          annotation="# $1"
          echo "append env variable to profile..."
          echo "the variable is :"
          echo "$annotation"
          echo "$home"
          echo "$sh"
          echo "It is appending now,please comfirm agagin:"
          echo "continue to input 'y', and input 'n' for exit.[y|n]?"
          read get_yes_or_no
          if [ $get_yes_or_no == "y" ]
          then
              sudo sed -i "4i\ \n" /etc/profile
              sudo sed -i "4i\\$sh" /etc/profile
              sudo sed -i "4i\\$home" /etc/profile
              sudo sed -i "4i\\$annotation" /etc/profile
              sudo source /etc/profile
              echo "$1 envirement virable was setted successfully!"
              echo "$1"
          else
              echo "exit!"
              exit
          fi
      else
          echo "Usage: set-env.sh JAVE_HOME."
          echo "Usage: set-env.sh help for help."
          exit
      fi
  else
      echo "create new profile failed. please to check ..."
  fi
else
  echo "exit!"
  exit
fi

  3. 玩具程序： 设置环境变量（第二版）

  ```shell
  #!/bin/babin
  # set env
  # by author nulijiubinimeili 2017
  
  time=`date +%Y%m%d%H%M%S`
  new_profile="profile_$time"
  
  
  echo "will create new profile $new_profile for backup."
  
  # check user, must be root
  if [ $UID -ne 0 ]
  then
    echo "Must to be use root to exec shell."
    exit
  fi
  
  # help info
  if [ $1 == "help" ]
        then
            echo "Usage: set-env.bin JAVE_HOME.(requer: this binell must in the java home directory.)"
            echo "Usage: set-env.bin /opt/modules/jdk1.8.0_161 JAVE_HOME"
            echo "Usage: set-env.bin help"
            exit
  fi
  
  echo "Appending this dir to envirement virable."
  echo "input y to continue and copy /etc/profile to $new_profile, the new file will as a backup for /etc/profile, if you want to use the old profile, you can rename the histry profile to 'profile'."
  echo "continue to input 'y', and input 'n' for exit.[y|n]?"
  read create_file_yes_or_no
  if [ $create_file_yes_or_no == "y" ] 
  then
    sudo cp /etc/profile /etc/$new_profile
    if [ $? -eq 0 ]
    then
        echo "create new profile success."
        if [ $# -eq 1 ]
        then
            # Must contains a bin directory in current path.
            if [ ! -d $PWD/bin ]
            then
                    echo -e "\033[32mWithout 'bin' directory in current path,pleash check.\033[0m"
                    exit
            fi
            # content=echo "# $1%nexport $1=$PWD%nexport PATH=\$PATH:\$$1/bin"
            echo "Recommend: set-env.x.x.x.sh /path XXX_HOME"
            bin="export PATH=\$PATH:\$$1/bin"
            home="export $1=$PWD"
            annotation="# $1"
            echo "append env variable to profile..."
            echo "the variable is :"
            echo -e "\033[32m$annotation\033[0m"
            echo -e "\033[32m$home\033[0m"
            echo -e "\033[32m$bin\033[0m"
            echo "It is appending now,please comfirm agagin:"
            echo "continue to input 'y', and input 'n' for exit.[y|n]?"
            read get_yes_or_no
            if [ $get_yes_or_no == "y" ]
            then
                sudo sed -i "4i\ \n" /etc/profile
                sudo sed -i "4i\\$bin" /etc/profile
                sudo sed -i "4i\\$home" /etc/profile
                sudo sed -i "4i\\$annotation" /etc/profile
                source /etc/profile
                echo "$1 envirement virable was setted successfully!"
                echo -e "\033[32mplease exec 'source /etc/profile' by yourself.\033[0m"
            else
                echo "exit!"
                exit
            fi
        elif [ $# == 2 ]
        then
            # content=echo "# $2%nexport $2=$PWD%nexport PATH=\$PATH:\$$2/bin"
            bin="export PATH=\$PATH:\$$2/bin"
            home="export $2=$1"
            annotation="# $2"
            echo "append env variable to profile..."
            echo "the variable is :"
            echo -e "\033[32m$annotation\033[0m"
            echo -e "\033[32m$home\033[0m"
            echo -e "\033[32m$bin\033[0m"
            echo "It is appending now,please comfirm agagin:"
            echo "continue to input 'y', and input 'n' for exit.[y|n]?"
            read get_yes_or_no
            if [ $get_yes_or_no == "y" ]
            then
                sudo sed -i "4i\\$bin" /etc/profile
                sudo sed -i "4i\\$home" /etc/profile
                sudo sed -i "4i\\$annotation" /etc/profile
                sudo sed -i "4i\ \n" /etc/profile
                source /etc/profile
                echo "$1 envirement virable was setted successfully!"
                echo -e "\033[32mplease exec 'source /etc/profile' by yourself.\033[0m"
            else
                echo "exit!"
                exit
            fi
        else
            echo "Usage: set-env.bin JAVE_HOME.(requer: this binell must in the java home directory.)"
            echo "Usage: set-env.bin /opt/modules/jdk1.8.0_161 JAVE_HOME"
            echo "Usage: set-env.bin help"
            exit
        fi
    else
        echo "create new profile failed. please to check ..."
    fi
  else
    echo "exit!"
    exit
  fi
  
  
  ```

  4. git 提交

  ```shell
  #!/bin/bash
  # git commit project
  # by author nulijiushimeili
  
  echo "start running shell"
  git add .
  if (($#>0));
  then
    git commit -m $1
  else
    echo "Usage: gitcommit.sh param1"
  fi
  git push orgin master
  
  if (($?==0))
  then
    echo "commit success."
  else
    echo "commit failed, please try to again."
  fi
  ```

  5. 启动Tomcat

  ```shell
  #!/bin/bash
  # 启动Tomcat
  tomPath=/usr/local/soft/tom7
  # sh ${tomPath}/bin/shutdown.sh
  # 作为参数返回 查找的进程ID 
  id=`ps -ef |grep tomcat |grep -v 'auto tomcat'|awk '{print $2}'`
  kill -9 $id
  rm -rf /usr/local/soft/tom7/webapps/ROOT*
  cp  /home/grq/data/ROOT.war /usr/local/soft/tom7/webapps/
  sh ${tomPath}/bin/startup.sh
  
  
  # 作为参数返回 查找的进程ID 
  id=$(ps -ef |grep tomcat |grep -v 'auto tomcat'|awk '{print $2}')
  
  ```

shell脚本编写

shell脚本编写

shell语法

summary

Hello World

获得执行的结果信息

变量的使用

if 语句

elseif 语句

for语句

while 语句

case语句

shell函数

按行读取文件

shell 编程知识

输出带颜色的打印信息

字体颜色设置

字体底色设置

特殊参数

逻辑运算符解析

测试脚本编写是否正确

文件IO

一些练习的小例子

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