HPC

Setting up a local perl library

Q: How do I install perl modules when I don’t have root access?

A: Set up a local perl library!

In order to install perl modules on C1, you will need to create a local perl library. In this example we will create our local library in a hidden directory within your home directory.

1. Create a new hidden directory, .perl

cd $HOME
mkdir .perl

2. Install the cpanm package manager and the local::lib package.

(Adapted from this stack exchange answer)

wget -O- http://cpanmin.us | perl - -l $HOME/.perl5 App::cpanminus local::lib

This what what the commands do:

wget -O- http://cpanmin.us fetches the latest version of cpanm and prints it to STDOUT which is then piped to perl - -l $HOME/.perl5 App::cpanminus local::lib. The first - tells perl to expect the program to come in on STDIN, this makes perl run the version of cpanm we just downloaded. perl passes the rest of the arguments to cpanm. The -l $HOME/.perl5 argument tells cpanm where to install Perl modules, and the other two arguments are two modules to install. App::cpanmins is the package that installs cpanm. local::lib is a helper module that manages the environment variables needed to run modules in local directory.

3. Set environment variables using local::lib

eval $(perl -I $HOME/.perl5/lib/perl5 -Mlocal::lib=$HOME/.perl5)

4. Add commands to .bashrc

This enables the local perl library every time you login:

echo 'eval $(perl -I $HOME/.perl5/lib/perl5 -Mlocal::lib=$HOME/.perl5)' >> .bashrc
echo 'export MANPATH=$HOME/.perl5/man:$MANPATH' >> .bashrc

5. Install additional perl packages

Perl packages can now be installed using cpanm Module::Name. For example, run the following command to install Log4perl:

cpanm Log::Log4perl