countdown

#!/usr/bin/perl
# countdown = sleep + verbosity
# countdown 300 && wget http://wu.sauceruney.com/digitrash/freemanradio/RadioFreeman01.mp3
use strict;
use warnings;
use AnyEvent;

$| = 1;
my $duration = shift;
my $count    = $duration;
my $len      = length($count);

my $done = AnyEvent->condvar;

my $w = AnyEvent->timer(
  after    => 0,
  interval => 1,
  cb       => sub {
    printf "[%${len}d/%${len}d]\r", $count--, $duration;
    $done->send if ($count < 0);
  }
);

$done->recv;
print "\n";