This is the Tie::TwoLevelHash module. It is a TIEHASH interface which lets you tie to a text file which is a multi-dimensional (two level) hash.

To use it, tie a hash to a directory:

tie(%hash, 'Tie::TwoLevelHash', $file, 'rw'); # Open in read/write mode

If you pass 'rw' as the third parameter, you'll be in read/write mode, and any changes you make to the hash will create or modify the file. If you don't open in read/write mode you'll be in read-only mode, and any changes you make to the hash won't have any effect in the given file. It's actually useless to tie to the file in read mode and make write calls to it, or the hash you are tying to it. If you do, it may croak, depending on what you are trying. If you want to grab values and play with them, do that in your script, and get the values out of the hash name you are tying with, so you can write to a local hash, and not affect, or try to affect the hash you are tying with.

A two level hash file (I use a .tlh extension) is a file after the same format as the defunct(?) Windows .ini files. A simple example of a small TLH file is as follows:

        # This is a TLH file
        # Comments on top of this file are allowed

        COLORS
                Red: #ff0000
                Black: #000000
                White: #ffffff

        PEOPLE
                Dog: Zeke
                Cat: Tigger
                PerlHacker: Randal
                Author: Kevin Meltzer

        EXTRA
                Key: Val
                Test: Vest

This file is a textual representation of a two-level hash, also known as a Hash of hashes. The file itself is the main hash, and each section contains another hash. So, this file contains the hash COLORS the hash PEOPLE and the hash EXTRA. Tie::TwoLevelHash allows for you to tie to the entire hash of hashes, or directly to one of the hashes within that hash of hashes. When you make a change in your script to the tied hash, it makes that change in your file.

EXAMPLES

Examples are given within the POD.

INSTALLATION

You install Apache::Htpasswd, as you would install any perl module library, by running these commands:

perl Makefile.PL
make
make test
make install
make clean

DOCUMENTATION

POD style documentation is included in the module. These are normally converted to manual pages and installed as part of the "make install" process. You should also be able to use the 'perldoc' utility to extract and read documentation from the module files directly.

AVAILABILITY

The latest version of Tie::TwoLevelHash should always be available from:

$CPAN/modules/by-authors/id/K/KM/KMELTZ/

Visit http://www.perl.com/CPAN/ to find a CPAN site near you.

COPYRIGHT

© 1998 Kevin Meltzer. All rights reserved.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

Enjoy!