howto return a structure from xml

Hello octave programmers, 

how can I build a structure within a octave function written
in c++?

My aim is to 
1. give a filename.xml to a octave function (works)

retval = readxml(name);

2. parse the xmlfile with help of libxml2 (works)
   <block1>
        <block2>content</block2>
   </block1>
   <block3>bla</block3>

3. retval should hold the xml structure, 

retval = root {
              block1 {
                     block2 = content;
                     }
              block3 = bla;
              }
(no idea so far)       

I am pretty new to octave programming; any help (which
manual to read etc - found nothing in liboctave doc) would
be appreciated!

Best

Jan-Mark

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 Phone: +49 30 314-2 45 88       FG  Nachrichtenübertragung
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