#!/usr/bin/perl -w 
use strict;
use Carp;
use File::Glob ':glob';
use Net::FTP;
use threads;
use Thread::Queue;
#use Attribute::Attempts;

my $MAX_THREADS = 10; 
my $file_queue  = new Thread::Queue;
my @files       = bsd_glob('~/*.html');
map { $file_queue->enqueue($_) } @files;
$file_queue->enqueue(undef);

my $ftp = Net::FTP->new('host.com')
    or croak "Cannot connect to host.com: $@";
$ftp->login( 'blah', 'blah' )
  or croak "Cannot login ", $ftp->message;

while (1) {
    for (
        my $needed = $MAX_THREADS - threads->list() ;
        $needed && $file_queue->peek ;
        $needed--
      )
    {   
        threads->create( \&ftp_put, $file_queue, $ftp )->join();
    }
    sleep(1) while threads->list() > 0;
    last unless $file_queue->peek;
}

$ftp->quit;

sub ftp_put    #: attempts(tries => 10)
{
    my ( $queue, $ftp ) = @_; 
    my $file = $queue->dequeue();
   $ftp->put( $file )
        or croak "get failed ", $ftp->message;
}