Author image Johan Wassberg
and 4 contributors


Config::File - Parse a simple configuration file


use Config::File;

my $config_hash = Config::File::read_config_file($configuration_file);


read_config_file parses a simple configuration file and stores its values in an anonymous hash reference. The syntax of the configuration file is as follows:

    # This is a comment
    VALUE_ONE = foo
    VALUE_THREE = The value contains a \# (hash). # This is a comment.

Options can be clustered when creating groups:

    CLUSTER_ONE[data] = data cluster one
    CLUSTER_ONE[value] = value cluster one
    CLUSTER_TWO[data] = data cluster two
    CLUSTER_TWO[value] = value cluster two

Then values can be fetched using this syntax:


There can be as many sub-options in a cluster as needed.

    BIG_CLUSTER[part1][part2][part3] = data

is fetched by: $hash_config->{BIG_CLUSTER}{part1}{part2}{part3};

There are a couple of restrictions as for the names of the keys. First of all, all the characters should be alphabetic, numeric, underscores or hyphens, with square brackets allowed for the clustering. That is, the keys should conform to /^[A-Za-z0-9_-]+$/

This means also that no space is allowed in the key part of the line.

    CLUSTER_ONE[data] = data cluster one      # Right
    CLUSTER_ONE[ data ] = data cluster one    # Wrong

Function read_config_file




$file is the configuration file.

Return value

This function returns a hash reference. Each key of the hash is a value defined in the configuration file.


read_config_file parses a configuration file a sets up some values in a hash reference.


Function not exported by default

In versions up to 1.0, the function read_config_file was exported to the calling program's namespace - Starting in version 1.1, nothing is exported by default. You can either fully qualify read_config_file or explicitly import it into your namespace:

Fully qualifying read_config_file
  use Config::File;

  my $config_hash = Config::File::read_config_file($configuration_file);
Explicitly importing read_config_file
  use Config::File qw(read_config_file);

  my $config_hash = read_config_file($configuration_file);

Migrated away from ConfigFile into Config::File

As of version 1.4, in order to include this module in the CPAN, I decided to move away from the highly unstandard name of ConfigFile and rename the module to Config::File. A small redirecting module is put in place, so current code using this module does not break, but the ConfigFile namespace usage is deprecated (and will thus issue a warning). Please update your code!


Development was started by Sebastien J. Gross <>. Maintained by Gunnar Wolf <> until 2018 when Stockholm University (Johan Wassberg and Mikael Nordin) took over maintainance.

All rights reserved. This program is free software; you can redistribute it and/or modify it under the terms of the GPL.


Version 1.54 Copyright (c) 2002 Sebastien J. Gross. All rights reserved. Copyright (c) 2003-2018 Gunnar Wolf. All rights reserved. Copyright (c) 2018- Stockholm University. All rights reserved. This program is free software; you can redistribute it and/or modify it under the terms of the GPL v2 (or later, at your choice).