$next_url = "http://blabla.com/cgi/script.cgi?";
$next_url .= "city=" . $city if($city);
...
$next_url =~ s/\?$//;   # remove question mark if no parameters added 
+to next_url
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Danikar, you could always save the CGI parameters into a standard CGI file via:

as documented in the CGI docs.

For each form submission, you'll need to generate a unique and retrievable key (which is the basis for the associated filename) so that you can identify which file belongs to that particular session. In your form, you'll need to include a hidden variable containing the value of this key so that it can be relayed through the form submission.

On the receiving side, create a FILEHANDLE to access the contents of your file. You can do this because you know the name of the file (via the hidden variable). There's a little housekeeping that happens afterwards (ie. deletion of the saved/expired CGI files, etc.).

It looks like this:

open(IFH, $CGI_filename) || die ...
my $query = CGI->new(IFH);
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Update: Please be aware that there are some security considerations that go along with this. You need to take the appropriate precautions as you deem necessary.

#!/usr/bin/perl
use warnings;
use CGI 'cgi';
use LWP::UserAgent;

our ($secure_server_address,$cgi_directory);
require './store_cfg';

print "Content-type: text/html\n\n";

#my $test= 'FALSE';
my $test= 'TRUE';
my $relay;
my $cgi = new CGI;
my %input= $cgi->Vars(); 
foreach $name (keys %input){
        $value = $input{$name};    
        $relay .= "$name=$value&";
         }
$relay .= "Ecom_transaction_complete=$test&";
$relay .= "IOC_response_code=0&";

open (RT,">test/respgen.test");
print RT $relay;
close RT;

my $ua = LWP::UserAgent->new();

my $req = HTTP::Request->new (POST => "$secure_server_address$cgi_dire
+ctory/boacc.pl");
$req->content_type('application/x-www-form-urlencoded');
$req->content("$relay");
my $res = $ua->request($req);
print $res->as_string;
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