I need conceptual clarification. I have fields of a form that I want to populate by letting a user use an XML file so my custom form module can parse and assign XML to form fields. I do not need to keep the XML file permanently.
First question: When using the file field widget on my form, after I select my file and the file name appears on the form, Drupal or the browser seem to have it stored in memory somewhere. It is possible to parse the XML file from this location in memory with a submit handler that populates the form? (So 2 submit handlers on the form, one to submit the XML to populate form and the other to submit the form to create node.)
Last question: Would this be easier if I have a form with a single file widget that uploads an XML file to a temp directory and builds + renders a form on the node after it has parsed the data?