12.3 Update Requests

     As mentioned before, an Update Request is really a File Request.
     The difference is that an Update Request is used to "update" a
     file that already exists on your system. The mailers accomplish
     this by transmitting the date and time of the existing file, the
     system that processes (receives) the Update Request then compares
     this with the requested filemask and sends any matching file that
     has a later date and time.