=encoding UTF-8

=head1 NAME

IP::China - decide whether an internet address is from China

=head1 SYNOPSIS

    use IP::China 'chinese_ip';
    if (chinese_ip ('127.0.0.1')) {
        print '你好';
    }

=head1 DESCRIPTION

Decide whether an IP address originates from China.

=head1 FUNCTIONS

The module has only one function:

=head2 chinese_ip

    my $is_chinese = chinese_ip ('255.255.255.255');

Given an internet protocol string (version 4), decide whether it is
Chinese or not. The return value is a true value (-1) if the address
is from China, and a false value (0) if the address is not from China.

=head1 UPDATES

The module will be periodically updated. Allocated addresses for China
may change. The script to build updates is included in the git
repository for this distribution. Please refer to F<Makefile.PL> for
the git repository URL.

The script also includes some errata for the MaxMind list.

=head1 ERRATA

The data block as follows:

    74.125.16.64/26,1814991,6252001,,0,0

is recorded as in China (country code 1814991), but this block seems
to belong to Google & not be in China, so this is discounted from the
results.

=head1 SEE ALSO

L<http://www.lemoda.net/networking/block-china/> contains an article
and some links to further information.


=head1 AUTHOR

Ben Bullock, <bkb@cpan.org>

=head1 COPYRIGHT & LICENCE

This package and associated files are copyright (C) 
2013-2017
Ben Bullock.

You can use, copy, modify and redistribute this package and associated
files under the Perl Artistic Licence or the GNU General Public
Licence.




=head2 DATA COPYRIGHT

This product includes GeoLite data created by MaxMind, available from
http://www.maxmind.com. The GeoLite databases are distributed under
the Creative Commons Attribution-ShareAlike 3.0 Unported License. The
GeoLite data is in the file F<block-china-data.c> of the distribution.