Uploading files to a server

starter08

Hi,
I have a C++ function for uploading files to a http server via a post request.
I am herewith attaching the C++ code.
Also on the server side I have written a simple cgi script to receive the data and create the file on the server in a specified directory.
However only a blank file is created everytime.
I am not sure whether there is something wrong in my C++ function or cgi script.
My cgi script is below
[code]
!/usr/bin/perl -wT

use strict;
use CGI;
use CGI::Carp qw ( fatalsToBrowser );
use File::Basename;

$CGI::POST_MAX = 10240 * 5000;
my $safe_filename_characters = "a-zA-Z0-9_.-";
my $upload_dir = "/usr/local/web/upload";

my $query = new CGI;
my $filename = $query->param("flat_file");
#my $email_address = $query->param("email_address");

if ( !$filename )
{
print $query->header ( );
print "There was a problem uploading your file (try a smaller file).";
exit;
}

my ( $name, $path, $extension ) = fileparse ( $filename, '..*' );
$filename = $name . $extension;
$filename =~ tr/ /_/;
$filename =~ s/[^$safe_filename_characters]//g;

if ( $filename =~ /^([$safe_filename_characters]+)$/ )
{
$filename = $1;
}
else
{
die "Filename contains invalid characters";
}

my $upload_filehandle = $query->upload("flat_file");

open ( UPLOADFILE, ">$upload_dir/$filename" ) or die "$!";
binmode UPLOADFILE;

while ( <$upload_filehandle> )
{
print UPLOADFILE;
}

close UPLOADFILE;

print $query->header ( );
[/code]
Appreciate if someone can point me in the right direction.
Thanks,