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Config::Auto - Magical config file parser


  use Config::Auto;

  # Not very magical at all.
  my $config = Config::Auto::parse("myprogram.conf", format => "colon");

  # Considerably more magical.
  my $config = Config::Auto::parse("myprogram.conf");

  # Highly magical.
  my $config = Config::Auto::parse();


This module was written after having to write Yet Another Config File Parser for some variety of colon-separated config. I decided "never again".

When you call Config::Auto::parse with no arguments, we first look at $0 to determine the program's name. Let's assume that's snerk. We look for the following files:


We take the first one we find, and examine it to determine what format it's in. The algorithm used is a heuristic "which is a fancy way of saying that it doesn't work." (Mark Dominus.) We know about colon separated, space separated, equals separated, XML, Perl code, Windows INI, BIND9 and irssi style config files. If it chooses the wrong one, you can force it with the format option.

If you don't want it ever to detect and execute config files which are made up of Perl code, set $Config::Auto::DisablePerl = 1.

Then the file is parsed and a data structure is returned. Since we're working magic, we have to do the best we can under the circumstances - "You rush a miracle man, you get rotten miracles." (Miracle Max) So there are no guarantees about the structure that's returned. If you have a fairly regular config file format, you'll get a regular data structure back. If your config file is confusing, so will the return structure be. Isn't life tragic?

Here's what we make of some common Unix config files:


    $VAR1 = {
          'nameserver' => [ '', '', '' ],
          'search' => [ '', '' ]


    $VAR1 = {
          'root' => [ 'x', '0', '0', 'root', '/root', '/bin/bash' ],


    $VAR1 = {
          'append' => '""',
          'responsiveness' => '',
          'device' => '/dev/psaux',
          'type' => 'ps2',
          'repeat_type' => 'ms3'


    $VAR1 = {
          'netgroup' => 'nis',
          'passwd' => 'compat',
          'hosts' => [ 'files', 'dns' ],


BIND9 and irssi file format parsers currently don't exist. It would be good to add support for mutt and vim style set-based RCs.


Simon Cozens,