Yes, you want the documentdata non-persistent attribute of DOCLINKS. If you include this non-persistent attribute in your object structure (using the Exclude/Include fields dialog in the Object Structures application) it should be able to write it to the XML file. Just be aware that the size of your XML file will grow significantly. I have seen records with 100 MB+ of attachments. That can then lead to issues with the other system being able to process the file.