Scripts ending in .pl will be executed within a Perl CGI handler.

Choosing a version of Perl

You can choose among multiple versions of Perl:

Perl version Command-line path Sunset Date
5.16 (default) /usr/bin/perl
5.30 /usr/local/bin/perl530 June 2024

If you need to switch Perl versions, you can do so by creating or editing your site's .silk.ini file (for example ~/www-root/.silk.ini) and adding the version to the [perl] section:

[perl]
version = 5.30

Valid version choices are default, any of the versions listed in the table above, or newest (which provides the newest available on the system).

Modules

Perl modules can be installed into your own repository with the cpanm command. SAA will assist upon request if header files or required libraries are missing.

You can set up a module environment in ~/perl5 with:

$ eval `perl -I ~/perl5/lib/perl5 -Mlocal::lib`
$ echo 'eval `perl -I ~/perl5/lib/perl5 -Mlocal::lib`' >> ~/.profile

Now you can install a module with cpanm <modulename>.

You can add ~/perl5 to Perl's @INC module include path by adding the following line at the top of your script:

use local::lib;

Then you can use any modules you have installed.

Example application

You can use the Mojolicious framework to create web applications of any size. The Lite version makes small applications particularly easy to create:

#!/usr/bin/perl
use Mojolicious::Lite;

get '/' => { text => 'Hello, world!' };

app->start;

Example basic CGI script

#!/usr/bin/perl

print("Content-Type: text/plain\n\n");

foreach $var (sort(keys(%ENV))) {
   $val = $ENV{$var};
   $val =~ s/\n/\\n/g;
   $val =~ s/"/\\"/g;
   print "${var}=\"${val}\"\n";
}