shell实例

从1叠加到100

echo $[$(echo +{1..100})]
echo $[(100+1)*(100/2)]
seq -s '+' 100 |bc

判断参数是否为空-空退出并打印null

#!/bin/sh
echo $1
name=${1:?"null"}
echo $name

循环数组

for ((i=0;i<${#o[*]};i++))
do
    echo ${o[$i]}
done

判断路径

if [ -d /root/Desktop/text/123 ];then
    echo "找到了123"
    if [ -d /root/Desktop/text ]
    then echo "找到了text"
    else echo "没找到text"
    fi
else echo "没找到123文件夹"
fi

找出出现次数最多

awk '{print $1}' file|sort |uniq -c|sort -k1r

判断脚本参数是否正确

./test.sh  -p 123 -P 3306 -h 127.0.0.1 -u root
#!/bin/sh
if [ $# -ne 8 ];then
    echo "USAGE: $0 -u user -p passwd -P port -h host"
    exit 1
fi

while getopts :u:p:P:h: name
do
    case $name in
    u)
        mysql_user=$OPTARG
    ;;
    p)
        mysql_passwd=$OPTARG
    ;;
    P)
        mysql_port=$OPTARG
    ;;
    h)
        mysql_host=$OPTARG
    ;;
    *)
        echo "USAGE: $0 -u user -p passwd -P port -h host"
        exit 1
    ;;
    esac
done

if [ -z $mysql_user ] || [ -z $mysql_passwd ] || [ -z $mysql_port ] || [ -z $mysql_host ]
then
    echo "USAGE: $0 -u user -p passwd -P port -h host"
    exit 1
fi

echo $mysql_user $mysql_passwd $mysql_port  $mysql_host
#结果 root 123 3306 127.0.0.1

正则匹配邮箱

^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,4})$

打印表格

#!/bin/sh
clear
awk 'BEGIN{
print "+--------------------+--------------------+";
printf "|%-20s|%-20s|\n","Name","Number";
print "+--------------------+--------------------+";
}'
a=`grep "^[A-Z]" a.txt |sort +1 -n |awk '{print $1":"$2}'`
#cat a.txt |sort +1 -n |while read list
for list in $a
do
    name=`echo $list |awk -F: '{print $1}'`
    number=`echo $list |awk -F: '{print $2}'`
    awk 'BEGIN{printf "|%-20s|%-20s|\n","'"$name"'","'"$number"'";
    print "+--------------------+--------------------+";
    }'
done
awk 'BEGIN{
print "              *** The End ***              "
print "                                           "

判断日期是否合法

#!/bin/sh
while read a
do
  if echo $a | grep -q "-" && date -d $a +%Y%m%d > /dev/null 2>&1
  then
    if echo $a | grep -e '^[0-9]\{4\}-[01][0-9]-[0-3][0-9]$'
    then
        break
    else
        echo "您输入的日期不合法，请从新输入！"
    fi
  else
    echo "您输入的日期不合法，请从新输入！"
  fi
done
echo "日期为$a"

打印日期段所有日期

#!/bin/bash
qsrq=20010101
jsrq=20010227
n=0
>tmp
while :;do
current=$(date +%Y%m%d -d"$n day $qsrq")
if [[ $current == $jsrq ]];then
    echo $current >>tmp;break
else
    echo $current >>tmp
    ((n++))
fi
done
rq=`awk 'NR==1{print}' tmp`

打印提示

cat <<EOF
#内容
EOF

登陆远程执行命令

# 特殊符号需要 \ 转义
ssh root@ip << EOF
#执行命令
EOF

数学计算的小算法

#!/bin/sh
A=1
B=1
while [ $A -le 10 ]
do
    SUM=`expr $A \* $B`
    echo "$SUM"
    if [ $A = 10 ]
    then
        B=`expr $B + 1`
        A=1
    fi
    A=`expr $A + 1`
done

多行合并

sed '{N;s/\n//}' file                   # 将两行合并一行(去掉换行符)
awk '{printf(NR%2!=0)?$0" ":$0" \n"}'   # 将两行合并一行
awk '{printf"%s ",$0}'                  # 将所有行合并
awk '{if (NR%4==0){print $0} else {printf"%s ",$0}}' file    # 将4行合并为一行(可扩展)

横竖转换

cat a.txt | xargs           # 列转行
cat a.txt | xargs -n1       # 行转列

竖行转横行

cat file|tr '\n' ' '
echo $(cat file)

#!/bin/sh
for i in `cat file`
do
      a=${a}" "${i}
done
echo $a

取用户的根目录

#! /bin/bash
while read name pass uid gid gecos home shell
do
    echo $home
done < /etc/passwd

远程打包

ssh -n $ip 'find '$path' /data /opt -type f  -name "*.sh" -or -name "*.py" -or -name "*.pl" |xargs tar zcvpf /tmp/data_backup.tar.gz'

把汉字转成encode格式

echo 论坛 | tr -d "\n" | xxd -i | sed -e "s/ 0x/%/g" | tr -d " ,\n"
%c2%db%cc%b3
echo 论坛 | tr -d "\n" | xxd -i | sed -e "s/ 0x/%/g" | tr -d " ,\n" | tr "[a-f]" "[A-F]"  # 大写的
%C2%DB%CC%B3

把目录带有大写字母的文件名改为全部小写

#!/bin/bash
for f in *;do
    mv $f `echo $f |tr "[A-Z]" "[a-z]"`
done

查找连续多行，在不连续的行前插入

#/bin/bash
lastrow=null
i=0
cat incl|while read line
do
i=`expr $i + 1`
if echo "$lastrow" | grep "#include <[A-Z].h>"
then
    if echo "$line" | grep -v  "#include <[A-Z].h>"
    then
        sed -i ''$i'i\\/\/All header files are include' incl
        i=`expr $i + 1`
    fi
fi
lastrow="$line"
done

查询数据库其它引擎

#/bin/bash
path1=/data/mysql/data/
dbpasswd=db123
#MyISAM或InnoDB
engine=InnoDB

if [ -d $path1 ];then

dir=`ls -p $path1 |awk '/\/$/'|awk -F'/' '{print $1}'`
    for db in $dir
    do
    number=`mysql -uroot -p$dbpasswd -A -S "$path1"mysql.sock -e "use ${db};show table status;" |grep -c $engine`
        if [ $number -ne 0 ];then
        echo "${db}"
        fi
    done
fi

批量修改数据库引擎

#/bin/bash
for db in test test1 test3
do
    tables=`mysql -uroot -pdb123 -A -S /data/mysql/data/mysql.sock -e "use $db;show tables;" |awk 'NR != 1{print}'`

    for table in $tables
    do
        mysql -uroot -pdb123 -A -S /data/mysql/data/mysql.sock -e "use $db;alter table $table engine=MyISAM;"
    done
done

将shell取到的数据插入mysql数据库

mysql -u$username -p$passwd -h$dbhost -P$dbport -A -e "
use $dbname;
insert into data values ('','$ip','$date','$time','$data')
"

两日期间隔天数

D1=`date -d '20070409' +"%s"`
D2=`date -d '20070304 ' +"%s"`
D3=$(($D1 - $D2))
echo $(($D3/60/60/24))

while执行ssh只循环一次

cat -    # 让cat读连接文件stdin的信息
seq 10 | while read line; do ssh localhost "cat -"; done        # 显示的9次是被ssh吃掉的
seq 10 | while read line; do ssh -n localhost "cat -"; done     # ssh加上-n参数可避免只循环一次

ssh批量执行命令

#版本1
#!/bin/bash
while read line
do
Ip=`echo $line|awk '{print $1}'`
Passwd=`echo $line|awk '{print $2}'`
ssh -n localhost "cat -"
sshpass -p "$Passwd" ssh -n -t -o StrictHostKeyChecking=no root@$Ip "id"
done<iplist.txt

#版本2
#!/bin/bash
Iplist=`awk '{print $1}' iplist.txt`
for Ip in $Iplist
do
Passwd=`awk '/'$Ip'/{print $2}' iplist.txt`
sshpass -p "$Passwd" ssh -n -t -o StrictHostKeyChecking=no root@$Ip "id"
done

在同一位置打印字符

#!/bin/bash
echo -ne "\t"
for i in `seq -w 100 -1 1`
do
    echo -ne "$i\b\b\b";      # 关键\b退格
    sleep 1;
done

多进程后台并发简易控制

#!/bin/bash
test () {
    echo $a
    sleep 5
}
for a in `seq 1 30`
do
    test &
    echo $!
    ((num++))
    if [ $num -eq 6 ];then
    echo "wait..."
    wait
    num=0
    fi
done
wait

shell并发

#!/bin/bash
tmpfile=$$.fifo   # 创建管道名称
mkfifo $tmpfile   # 创建管道
exec 4<>$tmpfile  # 创建文件标示4，以读写方式操作管道$tmpfile
rm $tmpfile       # 将创建的管道文件清除
thred=4           # 指定并发个数
seq=(1 2 3 4 5 6 7 8 9 21 22 23 24 25 31 32 33 34 35) # 创建任务列表

# 为并发线程创建相应个数的占位
{
for (( i = 1;i<=${thred};i++ ))
do
    echo;  # 因为read命令一次读取一行，一个echo默认输出一个换行符，所以为每个线程输出一个占位换行
done
} >&4      # 将占位信息写入管道

for id in ${seq}  # 从任务列表 seq 中按次序获取每一个任务
do
  read  # 读取一行，即fd4中的一个占位符
  (./ur_command ${id};echo >&4 ) &   # 在后台执行任务ur_command 并将任务 ${id} 赋给当前任务；任务执行完后在fd4种写入一个占位符
done <&4    # 指定fd4为整个for的标准输入
wait        # 等待所有在此shell脚本中启动的后台任务完成
exec 4>&-   # 关闭管道

#!/bin/bash

FifoFile="$$.fifo"
mkfifo $FifoFile
exec 6<>$FifoFile
rm $FifoFile
for ((i=0;i<=20;i++));do echo;done >&6

for u in `seq 1 $1`
do
    read -u6
    {
        curl -s http://ch.com >>/dev/null
        [ $? -eq 0 ] && echo "${u} 次成功" || echo "${u} 次失败"
        echo >&6
    } &
done
wait
exec 6>&-

shell并发函数

function ConCurrentCmd()
{
    #进程数
    Thread=30

    #列表文件
    CurFileName=iplist.txt

    #定义fifo文件
    FifoFile="$$.fifo"

    #新建一个fifo类型的文件
    mkfifo $FifoFile

    #将fd6与此fifo类型文件以读写的方式连接起来
    exec 6<>$FifoFile
    rm $FifoFile

    #事实上就是在文件描述符6中放置了$Thread个回车符
    for ((i=0;i<=$Thread;i++));do echo;done >&6

    #此后标准输入将来自fd5
    exec 5<$CurFileName

    #开始循环读取文件列表中的行
    Count=0
    while read -u5 line
    do
        read -u6
        let Count+=1
        # 此处定义一个子进程放到后台执行
        # 一个read -u6命令执行一次,就从fd6中减去一个回车符，然后向下执行
        # fd6中没有回车符的时候,就停在这了,从而实现了进程数量控制
        {
            echo $Count

            #这段代码框就是执行具体的操作了
            function

            echo >&6
            #当进程结束以后,再向fd6中追加一个回车符,即补上了read -u6减去的那个
        } &
    done

    #等待所有后台子进程结束
    wait

    #关闭fd6
    exec 6>&-

    #关闭fd5
    exec 5>&-

并发例子

    #!/bin/bash

    FifoFile="$$.fifo"
    mkfifo $FifoFile
    exec 6<>$FifoFile
    rm $FifoFile
    for ((i=0;i<=20;i++));do echo;done >&6

    for u in `seq 1 $1`
    do
        read -u6
        {
            curl -s http://m.chinanews.com/?tt_from=shownews >>/dev/null
            [ $? -eq 0 ] && echo "${u} 次成功" || echo "${u} 次失败"
            echo >&6
        } &
    done
    wait
    exec 6>&-

}

函数

ip(){
    echo "a 1"|awk '$1=="'"$1"'"{print $2}'
}
web=a
ip $web

检测软件包是否存在

rpm -q dialog >/dev/null
if [ "$?" -ge 1 ];then
    echo "install dialog,Please wait..."
    yum -y install dialog
    rpm -q dialog >/dev/null
    [ $? -ge 1 ] && echo "dialog installation failure,exit" && exit
    echo "dialog done"
    read
fi

游戏维护菜单-修改配置文件

#!/bin/bash

conf=serverlist.xml
AreaList=`awk -F '"' '/<s/{print $2}' $conf`

select area in $AreaList 全部 退出
do
    echo ""
    echo $area
    case $area in
    退出)
        exit
    ;;
    *)
        select operate in "修改版本号" "添加维护中" "删除维护中" "返回菜单"
        do
            echo ""
            echo $operate
            case $operate in
            修改版本号)
                echo 请输入版本号
                while read version
                do
                    if echo $version | grep -w 10[12][0-9][0-9][0-9][0-9][0-9][0-9]
                    then
                        break
                    fi
                    echo 请从新输入正确的版本号
                done
                case $area in
                全部)
                    case $version in
                    101*)
                        echo "请确认操作对 $area 体验区 $operate"
                        read
                        sed -i 's/101[0-9][0-9][0-9][0-9][0-9][0-9]/'$version'/' $conf
                    ;;
                    102*)
                        echo "请确认操作对 $area 正式区 $operate"
                        read
                        sed -i 's/102[0-9][0-9][0-9][0-9][0-9][0-9]/'$version'/' $conf
                    ;;
                    esac
                ;;
                *)
                    type=`awk -F '"' '/'$area'/{print $14}' $conf |cut -c1-3`
                    readtype=`echo $version |cut -c1-3`
                    if [ $type != $readtype ]
                    then
                        echo "版本号不对应，请从新操作"
                        continue
                    fi

                    echo "请确认操作对 $area 区 $operate"
                    read

                    awk -F '"' '/'$area'/{print $12}' $conf |xargs -i sed -i '/'{}'/s/10[12][0-9][0-9][0-9][0-9][0-9][0-9]/'$version'/' $conf
                ;;
                esac
            ;;
            添加维护中)
                case $area in
                全部)
                    echo "请确认操作对 $area 区 $operate"
                    read
                    awk -F '"' '/<s/{print $2}' $conf |xargs -i sed -i 's/'{}'/&维护中/' $conf
                ;;
                *)
                    echo "请确认操作对 $area 区 $operate"
                    read
                    sed -i 's/'$area'/&维护中/' $conf
                ;;
                esac
            ;;
            删除维护中)
                case $area in
                全部)
                    echo "请确认操作对 $area 区 $operate"
                    read
                    sed -i 's/维护中//' $conf
                ;;
                *)
                    echo "请确认操作对 $area 区 $operate"
                    read
                    sed -i '/'$area'/s/维护中//' $conf
                ;;
                esac
            ;;
            返回菜单)
                break
            ;;
            esac
        done
    ;;
    esac
    echo "回车重新选择区"
done

keepalive剔除后端服务

#!/bin/bash
#行数请自定义,默认8行
if [ X$2 == X ];then
    echo "error: IP null"
    read
    exit
fi
case $1 in
del)
    sed -i '/real_server.*'$2'.*8888/,+8 s/^/#/' /etc/keepalived/keepalived.conf
    /etc/init.d/keepalived reload
;;
add)
    sed -i '/real_server.*'$2'.*8888/,+8 s/^#//' /etc/keepalived/keepalived.conf
    /etc/init.d/keepalived reload
;;
*)
    echo "Parameter error"
;;
esac