#!/usr/bin/env perl
use strict;
use warnings;
use CGI qw(param header);
$|=1;

my $cgi = new CGI;
my @params = $cgi->param();

if (-t) {
    print "cmdline mode!\n";
}  else {
    print $cgi->header();
}


my $fmt;
if (-t) {
    $fmt = "%s:%s\n";
} else {
    $fmt = "%s:%s<br/>\n";
}
foreach my $p (@params) {
    # normally you'd make sure stuff is untainted here
    # but this is for demo purposes so I left it out
    printf($fmt, $p, $cgi->param($p));
}