#!perl

# this is 'tail' program which can be working on windows.
# on win32, perl's select() can't handle STDIN.
use strict;
use warnings;
use Filesys::Notify::Simple;

$|=1;
my $file = shift or die "usage: tail.pl [file]";
open my $fh, '<', $file;
seek $fh, 0, 2;
my $pos = tell($fh);
close $fh;
my $watcher = Filesys::Notify::Simple->new([ $file ]);
while (1) {
  $watcher->wait(sub {
    open $fh, '<', $file or die "maybe file was deleted?";
    seek $fh, $pos, 0;
    print $_ while <$fh>;
    seek $fh, 0, 2;
    $pos = tell($fh);
    close $fh;
  });
}