Submitting file fields?

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myrmi
2005-05-06
2013-05-30
  • myrmi
    myrmi
    2005-05-06

    I can't find any details on how to use the third variable that can be passed to the submit_form function; is it actually usable at this point in time, or is it merely there to aid future development? If the former is true, how do I go about using it?