将输出重定向到 bash 数组

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时间:2020-09-09 18:42:17  来源:igfitidea点击:

Redirect output to a bash array

bashshellredirect

提问by calvinkrishy

I have a file containing the string

我有一个包含字符串的文件

ipAddress=10.78.90.137;10.78.90.149

I'd like to place these two IP addresses in a bash array. To achieve that I tried the following:

我想将这两个 IP 地址放在一个 bash 数组中。为了实现这一点,我尝试了以下方法:

n=$(grep -i ipaddress /opt/ipfile |  cut -d'=' -f2 | tr ';' ' ')

This results in extracting the values alright but for some reason the size of the array is returned as 1 and I notice that both the values are identified as the first element in the array. That is

这导致提取值没问题,但由于某种原因,数组的大小返回为 1,我注意到这两个值都被标识为数组中的第一个元素。那是

echo ${n[0]}

returns

返回

10.78.90.137 10.78.90.149

How do I fix this?

我该如何解决?

Thanks for the help!

谢谢您的帮助!

回答by ghostdog74

do you really need an array

你真的需要一个数组吗

bash

猛击

$ ipAddress="10.78.90.137;10.78.90.149"
$ IFS=";"
$ set -- $ipAddress
$ echo 
10.78.90.137
$ echo 
10.78.90.149
$ unset IFS
$ echo $@ #this is "array"

if you want to put into array

如果你想放入数组

$ a=( $@ )
$ echo ${a[0]}
10.78.90.137
$ echo ${a[1]}
10.78.90.149

@OP, regarding your method: set your IFS to a space

@OP,关于你的方法:将你的 IFS 设置为一个空格

$ IFS=" "
$ n=( $(grep -i ipaddress file |  cut -d'=' -f2 | tr ';' ' ' | sed 's/"//g' ) )
$ echo ${n[1]}
10.78.90.149
$ echo ${n[0]}
10.78.90.137
$ unset IFS

Also, there is no need to use so many tools. you can just use awk, or simply the bash shell

此外,没有必要使用这么多工具。你可以只使用 awk,或者简单地使用 bash shell

#!/bin/bash
declare -a arr
while IFS="=" read -r caption addresses
do
 case "$caption" in 
    ipAddress*)
        addresses=${addresses//[\"]/}
        arr=( ${arr[@]} ${addresses//;/ } )
 esac
done < "file"
echo ${arr[@]}

output

输出

$ more file
foo
bar
ipAddress="10.78.91.138;10.78.90.150;10.77.1.101"
foo1
ipAddress="10.78.90.137;10.78.90.149"
bar1

$./shell.sh
10.78.91.138 10.78.90.150 10.77.1.101 10.78.90.137 10.78.90.149

gawk

呆呆的

$ n=( $(gawk -F"=" '/ipAddress/{gsub(/\"/,"",);gsub(/;/," ",) ;printf " "}' file) )
$ echo ${n[@]}
10.78.91.138 10.78.90.150 10.77.1.101 10.78.90.137 10.78.90.149

回答by Joy Dutta

This one works:

这个有效:

n=(`grep -i ipaddress filename | cut -d"=" -f2 | tr ';' ' '`)

EDIT: (improved, nestable version as per Dennis)

编辑:(根据丹尼斯的改进,可嵌套版本)

n=($(grep -i ipaddress filename | cut -d"=" -f2 | tr ';' ' '))

回答by Paused until further notice.

A variation on a theme:

一个主题的变体:

$ line=$(grep -i ipaddress /opt/ipfile)
$ saveIFS="$IFS"    # always save it and put it back to be safe
$ IFS="=;"
$ n=($line)
$ IFS="$saveIFS"
$ echo ${n[0]}
ipAddress
$ echo ${n[1]}
10.78.90.137
$ echo ${n[2]}
10.78.90.149

If the file has no other contents, you may not need the grepand you could read in the whole file.

如果文件没有其他内容,您可能不需要grep并且您可以读取整个文件。

$ saveIFS="$IFS"
$ IFS="=;"
$ n=$(</opt/ipfile)
$ IFS="$saveIFS"

回答by J. A. Faucett

A Perl solution:

Perl 解决方案:

n=($(perl -ne 's/ipAddress=(.*);/ / && print' filename))

which tests for and removes the unwanted characters in one operation.

它在一次操作中测试并删除不需要的字符。

回答by rashok

You can do this by using IFSin bash.

您可以通过使用IFSin来做到这一点bash

  • First read the first line from file.
  • Seoncd convert that to an array with =as delimeter.
  • Third convert the value to an array with ;as delimeter.
  • 首先从文件中读取第一行。
  • Seoncd 将其转换为带有=分隔符的数组。
  • 第三次将值转换为带有;分隔符的数组。

Thats it !!!

就是这样 !!!

#!/bin/bash
IFS='\n' read -r lstr < "a.txt"
IFS='=' read -r -a lstr_arr <<< $lstr
IFS=';' read -r -a ip_arr <<< ${lstr_arr[1]}
echo ${ip_arr[0]}
echo ${ip_arr[1]}