Linux Shell经典案例

itheima itheima

itcast
123

itheima

awk '/^$/{print NR}' file1.txt

张三 40
李四 50
王五 60

awk '{sum+=$2} END{print "求和: "sum}' file2.txt

if [ -e /root/file1.txt ]; then  echo "文件存在"; else echo "文件不存在"; fi

9
8
7
6
5
4
3
2
10
1

sort -n file3.txt | awk '{sum+=$1; print $1} END{print "求和: "sum}'

grep -r "123" /root | cut -d ":" -f 1| sort -u

#!/bin/bash
read -t 30 -p "请输入创建文件的数目:" n
test=$(echo $n | sed 's/[0-9]//g') #检测非数字输入
if [ -n "$n" -a -z "$test" ] #检测空输入
then
        for ((i=0;i<$n;i=i+1 ))
        do
                name=$(date +%N)
                [ ! -d ./temp ] &&  mkdir -p ./temp
                touch "./temp/$name"
                echo "创建 $name 成功!"
        done
        else
                echo "创建失败"
                exit 1
fi

rename 旧文件名 新文件名 旧文件所在位置

#!/bin/bash
filenames=$(ls /root/temp)
number=1
for name in $filenames
do
        printf "命令前:%s" ${name}
        newname=${name}"-"${number}
        rename $name ${newname} /root/temp/*
        let number++ #每个改名后的文件名后缀数字加1
        printf "重命名后:%s \n" ${newname}
done

user1
user2

useradd 用户名

echo "123456" | passwd --stdin 用户名

#!/bin/bash
ULIST=$(cat /root/users.txt)  ##/root/users.txt  里面存放的是用户名，一个名一行
for UNAME in $ULIST
do
        useradd $UNAME
        echo "123456" | passwd --stdin $UNAME &>/dev/null
        [ $? -eq 0 ] && echo "$UNAME用户名与密码添加初始化成功!"
done

I may not be able to change the past, but I can learn from it.

echo "I may not be able to change the past, but I can learn from it." | awk -F "[ ,.]" '{for(i=1;i<NF;i++){ if(length($i)>3){print $i}}}'

No. The Bible says Jesus had compassion2 on them for He saw them as sheep without a shepherd. They were like lost sheep, lost in their sin. How the Lord Jesus loved them! He knew they were helpless and needed a shepherd. And the Good Shepherd knew He had come to help them. But not just the people way back then. For the Lord Jesus knows all about you, and loves you too, and wants to help you.

awk -F "[,. ]+" '{for(i=1;i<=NF;i++)S[$i]++}END{for(key in S)print S[key],key}' file8.txt |sort -rn|head

awk -F "" '{for(i=1;i<=NF;i++)S[$i]++}END{for(key in S)print S[key],key}' file8.txt |sort -rn|head

ping ip地址 -c 2
# 如果ip地址存活发送2个数据包会至少接收返回1个数据包

#!/bin/bash
count=0
for i  in 192.168.56.{1..254}
do
    # 使用ping命令发送2个包测试, 并获取返回接收到包的个数
    receive=$(ping $i -c 2|awk 'NR==6{print $4}')
    # 接收返回包大于0 说明主机在线
    if [ ${receive} -gt 0 ]
    then
        echo "${i} 在线"
        ((count+=1))
    else
        echo "${i} 不在线"
    fi

done
echo "在线服务器有:"$count"个"

#!/bin/sh
user=root      #用户名
pass=root      #密码
backfile=/root/mysql/backup #备份路径
[ ! -d $backfile ] && mkdir -p $backfile #判断是否有备份路径
cmd="mysql -u$user -p$pass"  #登录数据库
dump="mysqldump -u$user -p$pass " #mysqldump备份参数
dblist=`$cmd -e "show databases;" 2>/dev/null |sed 1d|egrep -v "_schema|mysql"` #获取库名列表
echo "需要备份的数据列表:"
echo $dblist
echo "开始备份:"
for db_name in $dblist #for循环备份库列表
do
 printf '正在备份数据库:%s' ${db_name}
 $dump $db_name 2>/dev/null |gzip >${backfile}/${db_name}_$(date +%m%d).sql.gz #库名+时间备份打包至指定路径下
 printf ',备份完成\n'
done
echo "全部备份完成!!!"

#!/bin/sh
user=root      #用户名
pass=root      #密码
backfile=/root/mysql/backup #备份路径
[ ! -d $backfile ] && mkdir -p $backfile #判断是否有备份路径
cmd="mysql -u$user -p$pass"  #登录数据库
dump="mysqldump -u$user -p$pass " #mysqldump备份参数
dblist=`$cmd -e "show databases;" 2>/dev/null |sed 1d|egrep -v "_schema|mysql"` #获取库名列表
echo "需要备份的数据列表:"
echo $dblist
echo "开始备份:"
for db_name in $dblist #for循环备份库列表
do
 printf '正在备份数据库:%s\n' ${db_name}
 tables=`mysql -u$user -p"$pass" -e "use $db_name;show tables;" 2>/dev/null|sed 1d`
 for j in $tables
  do
    printf '正在备份数据库 %s 表 %s ' ${db_name} ${j}
    $dump -B --databases $db_name --tables $j 2>/dev/null > ${backfile}/${db_name}-${j}-`date +%m%d`.sql
    printf ',备份完成\n'
  done


 printf '数据库 %s 备份完成\n' ${db_name}
done
echo "全部备份完成!!!"