I've got a CGI script that I want to convert to PSGI. This is the result:

    use CGI::Emulate::PSGI;
    use strict;
    use warnings;
    use CGI qw(:cgi-lib :standard);
    use CGI::Carp qw(warningsToBrowser fatalsToBrowser);
    
    my $q = new CGI;
    
    my @keys = param();
    
    my $state = "";
    if(scalar @keys > 0){
        $state = $keys[0];
    }
    
    my $app = CGI::Emulate::PSGI->handler(sub {
        @keys = $q->param();
        print $q->header;
        print "<center>";
        print $q->h1('Some title');
        print "</center>";
        print $q->start_html(-title => 'Some title');
        print $keys[0];
        home();
        sub home{
            print "<center>";
            print $q->h3('Pick an option.');
            print $q->end_form;
            print "</center>";
            print "<center>";
            my $q0 = new CGI;
            print $q0->start_form(
                -name    => 'some_button',
                -method  => 'POST',
                -enctype => &CGI::URL_ENCODED,
            );
            print $q0->submit(
                -name     => 'click_me',
                -value    => 'Do something',
            );
            print $q0->end_form;
            print "</center>";
        }
        print $q->end_form;
    });
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After I click on 'Do something', I return to the same page (obviously), but it should print 'click_me'. This worked in CGI, but for some reason PSGI doesn't pass this variable. I can print other variables that are defined above. So my @keys = param(); doesn't seem to do a whole lot. Edit: Apparently PSGI uses %ENV, but I can't make it work with POST. It works with GET.

Edit: The solution is actually very easy. 'Your Mother' has the solution. I knew that you could compile your CGI scripts and emulate them. But if your run a perl server (like plackup), you get the next error: plackup: Variable "$variable" is not available at /location/of/script." The solution is to change the permissions of all global variables from 'my' to 'our'.