#!/usr/bin/perl -w

use strict;

use CGI;

oneheader();

my $q = new CGI;

print $q->header;
print $q->header;

close(STDOUT);
exit;

sub oneheader
{
    my $pid;
    my $seen = 0;
    return if $pid = open(STDOUT, "|-");
    die "cannot fork: $!" unless defined $pid;
    while(<STDIN>)
    {
        if(m/^Content-Type/)
        {
            print unless $seen;
            $seen = 1;
        }
        else
        {
             print;
        }
    }
    exit;
}

##</code><code>##

#!/usr/bin/perl -w

use strict;
use CGI;

tie *FILTER, "OneHeader";

my $q = new CGI;

select FILTER;

print $q->header;
print $q->header;

print "Foo!\n";

exit;

package OneHeader;
sub TIEHANDLE
{
    my $class = shift;
    my $me = 0;
    bless \$me, $class;
}

sub PRINT
{
    my $self = shift;
    foreach my $item (@_)
    {
        if($item =~ m/^Content-Type/)
        {
            if(not $$self)
            {
                $$self = 1;
                print STDOUT $item;
            }
        }
        else
        {
            print STDOUT $item;
        }
    }
    1;
}

1;