# $Id: README,v 5.1 2014/08/18 16:56:15 ronisaac Exp $
# Copyright (c) 2001-2014, Morgan Stanley.
# Distributed under the terms of the GNU General Public License.
# Please see the copyright notice at the end of this file for more information.
=========================
README FOR Env::Modulecmd
=========================
* WHAT IS IT?
By definition, from www.modules.org:
The Modules package provides for the dynamic modification of a
user's environment via modulefiles.
Each modulefile contains the information needed to configure the
shell for an application. Once the Modules package is initialized,
the environment can be modified on a per-module basis using the
module command which interprets modulefiles. Typically modulefiles
instruct the module command to alter or set shell environment
variables such as PATH, MANPATH, etc. modulefiles may be shared by
many users on a system and users may have their own collection to
supplement or replace the shared modulefiles
Here's an example: let's say you have several releases of xemacs
installed, and you want an easy way to choose your favorite release.
Here's a modulefile that might be called "xemacs/21.1.14":
#%Module
prepend-path PATH /usr/xemacs/21.1.14/bin
prepend-path MANPATH /usr/xemacs/21.1.14/man
Then there's a binary, called modulecmd, which outputs eval'able
code in a variety of languages. If your shell is ksh, you might
type: "eval `modulecmd ksh load xemacs/21.1.14`" to properly
configure your environment.
Now, modulecmd supports perl as well. If you issue the command
"modulecmd perl load xemacs/21.1.14", given the above modulefile, it
will spit out something like this (well not exactly, but here's a
simplified version):
$ENV{'PATH'} = "/usr/xemacs/21.1.14/bin:" . $ENV{'PATH'};
$ENV{'MANPATH'} = "/usr/xemacs/21.1.14/man:" . $ENV{'MANPATH'};
That's where Env::Modulecmd comes in. You say Env::Modulecmd::load
('xemacs/21.1.14') and it will run modulecmd and eval the output.
(It can also unload modules and do some other fancy stuff, like
check for errors.)
Note that this is useful only to people who use modulecmd and have
some modulefiles installed.
* INSTALLATION
To install this module type the following:
perl Makefile.PL
make
make test
make install
* DEFAULT PATHS
There are two environment variables that are critical to the operation
of both Env::Modulecmd and modulecmd itself:
PERL_MODULECMD
The full path to modulecmd. If present, Env::Modulecmd will always
use its value to invoke modulecmd. Otherwise, it will attempt to
invoke "modulecmd", relying on it being in the PATH.
MODULEPATH
A colon-separated list of directories where modulecmd itself
should look for modulefiles. Env::Modulecmd doesn't use this value
directly, but modulecmd will not work if it's not set properly, so
Env::Modulecmd can set it for you as a convenience.
At build time, you can specify default values for these two variables,
to be used in the event they're missing from the environment when
Env::Modulecmd is invoked. If you're building with perl5.005 or later,
give one or both of them as arguments to "make":
make DEFAULT_PERL_MODULECMD=/path/to/modulecmd DEFAULT_MODULEPATH=/a:/b:/c
If you're using perl5.004 or earlier, you'll need to edit Modulecmd.pm
by hand before installing. The two values go in the obvious spots near
the top of the file.
Note that these default values will work with any version of perl at
runtime; however, the facility used to replace the tokens in
Modulecmd.pm with the values supplied to "make" at build time requires
perl5.005 or better.
* DOCUMENTATION
See the pod documentation in Modulecmd.pm.
* COPYRIGHT AND LICENSE
Written by Ron Isaacson <
[email protected]>
Copyright (c) 2001-2014, Morgan Stanley.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or (at
your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307,
USA.
