使用Bash读取文件中的行并使用#避免行 [英] Reading lines in a file and avoiding lines with # with Bash

问题描述

我尝试过:

file="myfile"
while read -r line
do
    [[ $line = \#* ]] && continue
    "address=\$line\127.0.0.1"
done < "$file"

此代码无法避免以注释开头的行.即使我没有任何评论，dnsmasq也会告诉您有错误.

This code doesn't avoid the lines that begin with comments. Even if I don't have any comments, dnsmasq tells that there are errors.

它将是一个dnsmasq conf文件，它将读取并插入域名，如下所示:address=\mydomain.com\127.0.0.1.

Its going to be a dnsmasq conf file, and it will read and insert domain names like so: address=\mydomain.com\127.0.0.1.

输入文件:

domain1.com
domain2.com
domain3.com
#domain4.com
domain5.com

输出应为:

address=/domain1.com/127.0.0.1
address=/domain2.com/127.0.0.1
address=/domain3.com/127.0.0.1
address=/domain5.com/127.0.0.1

我将脚本放在/etc/dnsmasq.d/目录中，以便

I will drop the script in /etc/dnsmasq.d/ directory so that dnsmaq.conf can process it when dnsmasq is started.

推荐答案

使用[[ "$line" = "\#*" ]]

顺便说一句，address="\\${line}\\127.0.0.1"

UPD :

如果我理解的正确，则需要将每个未注释的域都更改为address=\domain\127.0.0.1.使用sed可以轻松快捷地完成此操作，无需使用bash程序.

If I've understand you right you need to change every uncommented domains to address=\domain\127.0.0.1. It could be done fast and easy with sed, there is no need in bash-program.

$> cat ./text
domain1.com
domain2.com
domain3.com
#domain4.com
domain5.com

$> sed -r -e 's/(^[^#]*$)/address=\/\1\/127.0.0.1/g' ./text2
address=/domain1.com/127.0.0.1
address=/domain2.com/127.0.0.1
address=/domain3.com/127.0.0.1
#domain4.com
address=/domain5.com/127.0.0.1

如果您需要删除注释行，sed也可以通过/matched_line/d

If you need to remove commented lines, sed can do it too with /matched_line/d

$> sed -r -e 's/(^[^#]*$)/address=\/\1\/127.0.0.1/g; /^#.*$/d' ./text2 
address=/domain1.com/127.0.0.1
address=/domain2.com/127.0.0.1
address=/domain3.com/127.0.0.1
address=/domain5.com/127.0.0.1

UPD2 :如果要在bash脚本中执行所有操作，请修改代码:

UPD2: if you want to do all that stuff inside the bash script, here is your code modification:

file="./text2"
while read -r line; do
    [[ "$line" =~ ^#.*$ ]] && continue
    echo "address=/${line}/127.0.0.1"
done < "$file"

它的输出是:

address=/domain1.com/127.0.0.1
address=/domain2.com/127.0.0.1
address=/domain3.com/127.0.0.1
address=/domain5.com/127.0.0.1

这篇关于使用Bash读取文件中的行并使用#避免行的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！