Section: Perl Programmers Reference Guide (1)
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config_data - Query or change configuration of Perl modules
# Get config/feature values
config_data --module Foo::Bar --feature bazzable
config_data --module Foo::Bar --config magic_number
# Set config/feature values
config_data --module Foo::Bar --set_feature bazzable=1
config_data --module Foo::Bar --set_config magic_number=42
# Print a usage message
The config_data tool provides a command-line interface to the
configuration of Perl modules. By configuration, we mean something
akin to user preferences or local settings. This is a
formalization and abstraction of the systems that people like Andreas
Koenig (CPAN::Config), Jon Swartz (HTML::Mason::Config), Andy
Wardley (Template::Config), and Larry Wall (perl's own Config.pm)
have developed independently.
The configuration system emplyed here was developed in the context of
Module::Build. Under this system, configuration information for a
module Foo, for example, is stored in a module called
Foo::ConfigData) (I would have called it Foo::Config, but that
was taken by all those other systems mentioned in the previous
paragraph...). These ...::ConfigData modules contain the
configuration data, as well as publically accessible methods for
querying and setting (yes, actually re-writing) the configuration
data. The config_data script (whose docs you are currently
reading) is merely a front-end for those methods. If you wish, you
may create alternate front-ends.
The two types of data that may be stored are called config values
and feature values. A config value may be any perl scalar,
including references to complex data structures. It must, however, be
serializable using Data::Dumper. A feature is a boolean (1 or
This script functions as a basic getter/setter wrapper around the
configuration of a single module. On the command line, specify which
module's configuration you're interested in, and pass options to get
or set config or feature values. The following options are
Specifies the name of the module to configure (required).
When passed the name of a feature, shows its value. The value will
be 1 if the feature is enabled, 0 if the feature is not enabled, or
empty if the feature is unknown. When no feature name is supplied,
the names and values of all known features will be shown.
When passed the name of a config entry, shows its value. The value
will be displayed using Data::Dumper (or similar) as perl code.
When no config name is supplied, the names and values of all known
config entries will be shown.
Sets the given feature to the given boolean value. Specify the value
as either 1 or 0.
Sets the given config entry to the given value.
If the --eval option is used, the values in set_config will be
evaluated as perl code before being stored. This allows moderately
complicated data structures to be stored. For really complicated
structures, you probably shouldn't use this command-line interface,
just use the Perl API instead.
Prints a help message, including a few examples, and exits.
Ken Williams, email@example.com
Copyright (c) 1999, Ken Williams. All rights reserved.
This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.
- SEE ALSO
This document was created by
using the manual pages.