use XML::LibXML;

my $parser = XML::LibXML->new();
my $data = $parser->parse_file($xml_file);
my @nodes = $data->findnodes("/info/city");


##</code><code>##

<?xml version="1.0"?>

<info
xmlns="http://www.mydomain.com"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.mydomain.com infoschema.xsd">

<name>john</name>
<city>baltimore</city>
<zip>21205</zip>
</info>