thanks. that solved the problem with the missing parents. I still have the problem with how to select on a specific node. I'm still getting two nodes recognized. I did correct one typo with the object name, and I no longer get a parsing error, but I still cant figure out how to select the specific myobj that I'm looking for. modified example (got rid of spaces in demo.xml uniqueName node, and added the '@' in front of uniqueName in the handler filter.

use strict;
use warnings;
        
use English;
use XML::Twig;
            
my $xmlFile = "demo.xml";
    
my $t = XML::Twig->new(
        keep_atts_order => 1, 
        pretty_print => 'indented_a',
        twig_handlers => { 
            q(myconfig/myobj[@uniqueName=objA]/myattributes/attribB) =
+> \&getfoo,
        }
);  
$t->parsefile( $xmlFile );
$t->print;

exit 0;

sub getfoo {
    my ($t, $e) = @_;
    print "text=", $e->text(), 
          "' tag='", $e->tag(), 
          "' path='", $e->path(),
          "' parentTag='", $e->parent->tag(), "'\n";
}
[download]

output:

text= fooB ' tag='attribB' path='/myconfig/myobj/myattributes/attribB'
+ parentTag='myattributes'
text= fooB ' tag='attribB' path='/myconfig/myobj/myattributes/attribB'
+ parentTag='myattributes'
<myconfig>
  <myobj>
    <uniqueName>objA</uniqueName>
    <myattributes>
      <attribA> fooA </attribA>
      <attribB> fooB </attribB>
    </myattributes>
  </myobj>
  <myobj>
    <uniqueName>objB</uniqueName>
    <myattributes>
      <attribA> fooA </attribA>
      <attribB> fooB </attribB>
    </myattributes>
  </myobj>
</myconfig>
[download]

@ is for attributes. Remove the whole predicate, Twig doesn't understand it anyway. Just extract the uniqueName element, compare it to the wanted id, and change the element:

#!/usr/bin/perl
use warnings;
use strict;

use XML::Twig;

my $xmlFile = 'demo.xml';
my $t = XML::Twig->new( keep_atts_order => 1,
                        pretty_print    => 'indented_a',
                        twig_handlers   => {
                            'myconfig/myobj/myattributes/attribB' => \
+&getfoo,
                                           },
                      );
$t->parsefile($xmlFile);
$t->print;

sub getfoo {
    my ($t, $e) = @_;
    my $id = $e->parent->parent->first_child_text('uniqueName');
    if ('objB' eq $id) {
        $e->set_text(' NEW ');
    }
}
[download]

For comparison, the same task in XML::XSH2:

open demo.xml ;
set /myconfig/myobj[uniqueName='objB']/myattributes/attribB 'NEW' ;
save :b ;
[download]

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