/ 
BaseLib-0.03
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/ BaseLib

NAME

BaseLib - manipulate @INC dynamically for independent installation path

SYNOPSIS

use BaseLib qw(BASEDIR LIBDIR);

or just,

use BaseLib;

DESCRIPTION

If you have a set of application with certain file structure under a base directory, e.g. pim, and it has a private modules directory called lib-perl, and it's intalled under /usr/local. For the application to work, the scripts may need to say:

use lib '/usr/local/pim/lib-perl';

Someday, you need to move the application to, say, /vhost/www.some.host.com, so you need to change the use statement all over the scripts to:

use lib '/vhost/www.some.host.com/pim/lib-perl';

If you do this a lot and get tired of changing the line for every different installation path, or, you don't want to bother people using your application to cange the line to meet their conditions, then you might need this module.

Now your scripts can say:

use BaseLib qw(pim lib-perl);

where pim and lib-perl are the BASEDIR and LIBDIR arguments respectively.

So there's no need to worry about different installation layout, wherever the pim base directory is put under. The BASEDIR argument is required while LIBDIR is optional (defaults to lib).

As addition, you can use BaseLib's global package variable, $BaseDir to refer to the full path to pim. For example, assuming the application is installed under /usr/local, then

print "Data dir: $BaseLib::BaseDir/data\n";

will print,

Data dir: /usr/local/pim/data

Yes, you must qualify it with the package name since the variable is not exportable. This may change in the future.

NOTE

Please consider this module, the code and its interface, as in ALPHA stage. Expect any change in the future versions.

CAVEATS

I only tested it in the following environment:

* Perl 5.005_03
* Linux

It's unlikely to work on systems don't recognize / as path separator.

BaseLib will find the last occurence of BASEDIR string. If you mean the base directory as /usr/local/myapp, while the script uses the module locates in /usr/local/myapp/bin/sample/myapp/test/script.pl, then the full path to the application base directory ends in /usr/local/myapp/bin/sample/myapp.

In mod_perl environment there's a high risk for conflict on the $BaseLib::BaseDir if BaseLib is used by more than one application in the same host.

But any improvements/suggestions for wider support are welcome. A simple comment on this module will do as well.

AUTHOR

This module is written by Hasanuddin Tamir <hasant@trabas.com>.

Copyright (C) 2000 Trabas. All rights reserved.

This software is freeware. You may redistribute it and/or modify it under the same terms as Perl itself.

SEE ALSO

lib, FindBin