使用sed修改Apache端口文件

Question

I am trying to edit Listen 80 in ports.conf file with sed.

Since that file looks like :

Listen 80

<IfModule ssl_module>
    Listen 443
</IfModule>

<IfModule mod_gnutls.c>
    Listen 443
</IfModule>

with this command: head -n1 sed_test | sed -i -e 's/Listen [0-9]+/Listen 80/1p' sed_test

It changes all 'Listen $port_number' in the file. I guess it is because in second command I specify a file.

If I don't specify, to which file it should write, I get an error sed: no input files which is logical although.

I know that it can be done only with a sed, but I am unsure how to edit only one line and replace it with my custom value.

So this is what I want to accomplish:

sed -i -e some_command/Listen 8080 file

cat file ->

 Listen 8080

    <IfModule ssl_module>
        Listen 443
    </IfModule>

    <IfModule mod_gnutls.c>
        Listen 443
    </IfModule>

How to do that?

Answer 1

If you are using gnu sed you can use:

sed -i '0,/Listen [0-9]*/s//Listen 8080/' file

Listen 8080

<IfModule ssl_module>
    Listen 443
</IfModule>

<IfModule mod_gnutls.c>
    Listen 443
</IfModule>

If you don't have gnu sed then you can use awk to replace only first instance:

awk '!p{ p=sub(/Listen [0-9]*/, "Listen 8080") } 1' file

Listen 8080

<IfModule ssl_module>
    Listen 443
</IfModule>

<IfModule mod_gnutls.c>
    Listen 443
</IfModule>

Answer 2

这可以通过标准sed来完成：

sed '/Listen/{s/\([0-9]\+\)/8080/; :a;n; ba}' file