hello
i figured this out!
while i couldnt find anything about the validate or
get_last _error functions i did manage to get code to werk!

thanks matt!

here is a sample xml:

<?xml version="1.0"?>
<!DOCTYPE roots SYSTEM 'dtd.dtd'>
<roots>
<child1 attrib="3"></child1>
<child2></child2>
<child3/>
</roots>
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the dtd:

<!ELEMENT roots (child1,child2,child3)>
  <!ELEMENT child1      (#PCDATA)>
<!ATTLIST child1 attrib CDATA #REQUIRED>
  <!ELEMENT child2  EMPTY>
  <!ELEMENT child3  (#PCDATA)>
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and the perl script:

#!/usr/bin/perl
use strict;
use XML::LibXML;
my $parser = XML::LibXML->new();
$parser->validation(1);
eval {print "xml is valid=".$parser->parse_file('xml.xml')->is_valid  
+."\n"; };

if ($@) {    print "dtd not valid: $@\n";}
else {    print "dtd valid\n";}
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hope this helps anyone else in the future