Need help with a simple (I think) Perl script

First of all, I am a rank amateur at Perl. Here is my problem: I have a
hundred or more files in a directory on a web server (let's call it
'Library'). Each file is a pdf file and is named 'yyyymmm.pdf' where yyyy
is the year (i.e. 2007) and mmm is the first 3 letters of the month (i.e.
Jan). So a typical file name looks like '2007Jan.pdf'.

I wrote a simple html page using FORM that allows the user to select the
year and the month and then press the SUBMIT button and I want the
respective pdf file returned into the users browser. The problem is, I
don't know how to return a pdf file to the browser.

Here's what I have so far:

#!/usr/local/bin/perl -wT
use strict;
use CGI ':standard';

# declare variables...
my $year;
my $month;
my $pdffile;

# get the parameters...
$year = param('Year');
$month = param('Month');

# construct the relative pathname to the actual PDF file
$pdffile = '../Library/'.$Year.$Month.'.pdf';

print 'Content-type: application/pdf\n\n';

This is where I'm stuck. Can someone push me in the right direction. I
would think it should be trivial. I just don't know how to procede.

Thanks in advance...

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