$book->booking(oid => 'foo', begin => '1.3.2012', end => '15.3.2012') or die $@;

use strict;
use warnings;
use Data::Dumper;
my $file = '/tmp/book.bin';
my $book = Booking::Day->new($file, rw => 1) or die $@;
# gewünschten Zeitraum freigeben, reason => 0
$book->booking(oid => 'foo', begin => '1.1.2012', end => '10.1.2012', reason => 0) or die $@;
# neuen Zeitraum buchen
$book->booking(oid => 'foo', begin => '3.1.2012', end => '9.1.2012', reason => 'vergeben') or die $@;
# Zeitraum ausgeben
my $terms = $book->read( oid => 'foo', begin => '1.1.2012', end => '31.1.2012') or die $@;
print Dumper $terms;