#!/usr/bin/perl -w
use strict;
use CGI::Carp qw/fatalsToBrowser warningsToBrowser/;
use CGI qw/:standard/;
$|++;

my $fontname = "italic 1em Arial, sans-serif";
open F, '>', "output.html" or die "output.html: $!\n";

print F start_html,
        div({ style => "font: $fontname;" }, "\n",
            pre("Hello, World!"), "\n",
            pre("CGI example, with font '$fontname'")
        ),
        end_html;

##</code><code>##

my %s;
@s{split //, '<>&'} = qw/lt gt amp/;
my $text = do { local $/; <Input> };
$text =~ s/([<>&])/"&$s{$1};"/ges;