$ sudo perl -MCPAN -e shell
Password:
cpan shell -- CPAN exploration and modules installation (v1.9600)
cpan> 

##</code><code>##

$ sudo /usr/bin/perl -MCPAN -e shell
Password:
cpan shell -- CPAN exploration and modules installation (v1.7602)
cpan>

##</code><code>##

sudo /usr/bin/perl -MCPAN -e 'install File::Basename'