运维Shell脚本小试牛刀(三)::$(cd $(dirname $0)； pwd)命令详解

运维Shell脚本小试牛刀(一)

运维Shell脚本小试牛刀(二)

运维Shell脚本小试牛刀(三)::$(cd $(dirname $0)； pwd)命令详解

一： $(cd $(dirname $0); pwd) 命令详解

path = $(cd $(dirname $0); pwd)解析：

1、取当前运行脚本的所在路径：　$0

2、取当前脚本所在路径的父目录：　dirname

3、取返回的父目录的值：　$(dirname $0)

4、cd到返回的父目录：　cd “$(dirname “$0”)”

5、输出地址：　$(cd $(dirname $0); pwd)

6、取输出的地址，并赋值给path：　path = $(cd (dirname $0),pwd)

$0 获取运行脚本文件所在路径，在命令行种执行结果为 -bash

[root@www ~]# echo "$0"
-bash

二： Linux中变量#,@,0,1,2,*,$$,$? 普及

Linux中变量#,@,0,1,2,*,$$,$?的含义

$# 是传给脚本的参数个数

$

0

是脚本本身的名字

$

1

是传递给该shell脚本的第一个参数

$

2

是传递给该shell脚本的第二个参数

$@ 是传给脚本的所有参数的列表

$* 是以一个单字符串显示所有向脚本传递的参数，与位置变量不同，参数可超过

9

个

$$ 是脚本运行的当前进程ID号

$? 是显示最后命令的退出状态，

0

表示没有错误，其他表示有错误

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区别：@@*

• 相同点：都是引用所有参数
• 不同点：只有在双引号中体现出来。假设在脚本运行时写了三个参数（分别存储在112 3）则"3）则"*" 等价于 “112 3"（传递了一个参数）；而“3"（传递了一个参数）；而“@" 等价于 "1""1""2" "$3"（传递了三个参数）

小试牛刀一:

**

[root@www tools]# cat commandList.sh

**

echo "number:$#"
echo "scname:$0"
echo "first :$1"
echo "second:$2"
echo "argume:$@"
echo "show parm list:$*"
echo "show process id:$$"
echo "show precomm stat: $?"

---

输出：

[root@www example]# ./commandList.sh 1 20 111 2 5 6 7 3
number:8
scname:./commandList.sh
first :1
second:20
argume:1 20 111 2 5 6 7 3
show parm list:1 20 111 2 5 6 7 3
show process id:3465
show precomm stat: 0

---

小试牛刀二:

[root@www example]# cat commandOutList.sh
#!/bin/sh
num=$#
name=$0
echo "number:$num"
echo "scname:$name"
echo $0
echo $1
echo $2

for ((i=0; i<$num; i++))
do
echo "$i"
done

echo "argume:$@"
for key in $@
do
echo $key
done
echo "-----------------"
for key in "$@"
do
echo $key
done
echo "-----------------------------"
for key2 in $*
do
echo $key2
done
echo "-----------------"
for key2 in "$*"
do
echo $key2
done

echo "show process id:$$"
echo
echo "show precomm stat: $?"

---

输出内容：

[root@www example]# ./commandOutList.sh
number:0
scname:./commandOutList.sh
./commandOutList.sh

argume:

---

---

show process id:3514

show precomm stat: 0

[root@www tools]# sudo yum install rsync -y
rsync和scp区别：用rsync做文件的复制要比scp的速度快，rsync只对差异文件做更新。scp是把所有文件都复制过去。

三： 批量拷贝脚本

**创建分发脚本文件：

xsync   脚本内容

**

**

[root@www tools]#  cat ~/bin/xsync 

**

**

#!/bin/bash
 #1. 判断参数个数
 if [ $# -lt 1 ]
 then
     echo Not Enough Arguement!
     exit;
 fi

**

**

#2. 遍历集群所有机器|docker0|docker1|docker2| 
 for host in docker0 docker1 docker2
 do
     echo ====================  $host  ====================
     
     #3. 遍历所有目录，挨个发送
     for file in $@
     do
         #4. 判断文件是否存在
         if [ -e $file ]
             then
                 #5. 获取父目录
                 pdir=$(cd -P $(dirname $file); pwd)
                 #6. 获取当前文件的名称
                 fname=$(basename $file)
                 ssh $host "mkdir -p $pdir"
                 rsync -av $pdir/$fname $host:$pdir
             else
                 echo $file does not exists!
         fi
     done
 done

**

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小试牛刀一:

**

将jdk分发到docker1,docker2服务器上

**

[root@www bin]# ./xsync /usr/local/tools/jdk-8u371-linux-x64.tar.gz
==================== docker0 ====================
sending incremental file list

sent 66 bytes received 12 bytes 156.00 bytes/sec
total size is 139,219,380 speedup is 1,784,863.85
==================== docker1 ====================
sending incremental file list
jdk-8u371-linux-x64.tar.gz

sent 139,253,473 bytes received 35 bytes 39,786,716.57 bytes/sec
total size is 139,219,380 speedup is 1.00
==================== docker2 ====================
sending incremental file list
jdk-8u371-linux-x64.tar.gz

sent 139,253,473 bytes received 35 bytes 39,786,716.57 bytes/sec
total size is 139,219,380 speedup is 1.00

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小试牛刀二:

[root@www bin]# ./xsync /usr/local/zookeeper/

将解压后的zookeeper文件全拷贝到docker1|docker2机器：

[root@www bin]# ./xsync /usr/local/zookeeper/
==================== docker0 ====================
sending incremental file list

sent 61,605 bytes received 227 bytes 123,664.00 bytes/sec
total size is 390,744,347 speedup is 6,319.45
==================== docker1 ====================
sending incremental file list

sent 61,613 bytes received 235 bytes 123,696.00 bytes/sec
total size is 390,744,347 speedup is 6,317.82
==================== docker2 ====================
sending incremental file list

sent 61,613 bytes received 235 bytes 123,696.00 bytes/sec
total size is 390,744,347 speedup is 6,317.82

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