需要Perl在命令行上就地编辑文件 [英] Need Perl inplace editing of files not on command line

问题描述

我有一个程序，该程序在内部配置了许多文件名.该程序将编辑与数据库帐户关联的一堆配置文件，然后更改该数据库帐户的数据库密码.

I have a program that has a number of filenames configured internally. The program edits a bunch of configuration files associated with a database account, and then changes the database password for the database account.

配置文件列表通过内部列表与数据库帐户的名称相关联.处理这些文件时，我的程序中存在以下循环:

The list of configuration files is associated with the name of the database account via an internal list. When I process these files, I have the following loop in my program:

BEGIN { $^I = '.oldPW'; }  # Enable in-place editing
...
foreach (@{$Services{$request}{'files'}})
{
    my $filename = $Services{$request}{'configDir'} . '/' . $_;
    print "Processing ${filename}\n";
    open CONFIGFILE, '+<', $filename or warn $!;
    while (<CONFIGFILE>)
    {
        s/$oldPass/$newPass/;
        print;
    }
    close CONFIGFILE;
}

问题是，这会将修改后的输出写入STDOUT，而不是CONFIGFILE.如何获得此内容以进行实际编辑?将$ ^ I移入循环?打印CONFIGFILE?我很困惑.

The problem is, this writes the modified output to STDOUT, not CONFIGFILE. How do I get this to actually edit inplace? Move the $^I inside the loop? Print CONFIGFILE? I'm stumped.

>

更新:我在PerlMonks上找到了 一个>.您可以在循环内使用本地ARGV以常规Perl方式进行就地编辑.上面的循环现在看起来像:

Update: I found what I was looking for on PerlMonks. You can use a local ARGV inside the loop to do inplace editing in the normal Perl way. The above loop now looks like:

foreach (@{$Services{$request}{'files'}})
{
    my $filename = $Services{$request}{'configDir'} . '/' . $_;
    print "Processing ${filename}\n";
    {
        local @ARGV = ( $filename);
        while (<>)
        {
            s/$oldPass/$newPass/;
            print;
        }
    }
}

如果不是一开始就使用configDir，我可以将整个列表扔到本地@ARGV中，但这足够有效.

If it weren't for tacking the configDir on the beginning, I could just toss the whole list into the local @ARGV, but this is efficient enough.

感谢有关Tie::File的有用建议.如果这样做了，我可能会走那条路.我正在编辑的配置文件的长度从不超过几KB，因此Tie不会使用过多的内存.

Thanks for the helpful suggestions on Tie::File. I'd probably go that way if doing this over. The configuration files I'm editing are never more than a few  KB in length, so a Tie wouldn't use too much memory.

推荐答案

File::Slurp 提供方便的功能edit_file和edit_file_lines.您的代码的内部看起来应该是:

The recent versions of File::Slurp provide convenient functions, edit_file and edit_file_lines. The inner part of your code would look:

use File::Slurp qw(edit_file);
edit_file { s/$oldPass/$newPass/g } $filename;

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