[SOLVED] How can I use CPAN as a non-root user?

How can I use CPAN as a non-root user?

I want to install perl modules on a shared server on which I do not have root access. How can I do this? They also seem to have an older version of CPAN (it complains about that when running the command), is it possible to update the CPAN command being used from my account without requiring root access?

Solution

You can use cpanminus and the local::lib module.

The easiest method I have found so far is to say:

wget -O- http://cpanmin.us | perl - -l ~/perl5 App::cpanminus local::lib
eval `perl -I ~/perl5/lib/perl5 -Mlocal::lib`
echo 'eval `perl -I ~/perl5/lib/perl5 -Mlocal::lib`' >> ~/.profile
echo 'export MANPATH=$HOME/perl5/man:$MANPATH' >> ~/.profile

This assumes your profile is named .profile, you may need to change that to be .bash_profile, .bashrc, etc. After that you can install modules by saying

cpanm Module::Name

and simply use them the same way you would if the were installed in the root directories.

What follows is a brief explanation of what the commands above do.

Now,

wget -O- http://cpanmin.us fetches the latest version of cpanm, the cpa and prints it to STDOUT
The downloaded script is then piped to perl - -l ~/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 ~/perl5 argument tells cpanm where to install Perl modules, and the other two arguments are two modules to install:
- [App::cpanminus]3 is the package that installs cpanm. This installation is how cpanminus bootstraps: The script we downloaded now installs itself as an app.
- local::lib is a helper module that manages the environment variables needed to run modules in local directory.
Now that the installation itself is complete, we run:
```
eval `perl -I ~/perl5/lib/perl5 -Mlocal::lib`
```
to set the environment variables needed to use the local modules in this shell session, and
```
echo 'eval `perl -I ~/perl5/lib/perl5 -Mlocal::lib`' >> ~/.profile
```
to ensure we set them in our next login shell session.
Finally, we ensure future login shell sessions will have the local modules' man-help pages available for the man utility to search, with
```
echo 'export MANPATH=$HOME/perl5/man:$MANPATH' >> ~/.profile
```
this will hopefully cause man to find the man pages for your local modules.