How do I run a GRASS script from "cron" ?

GRASS GRASS user
1

   I have some maps that display the latest streamflow and
   precipitation at our gage sites. The gage data is updated hourly.
   How can I run grass from a background cron process to
   automatically execute the script that updates the maps. I know
   how to use cron reasonably well, I just don't know how to
   run a full grass session from a script.

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  John Del Ferro U.S. Army Corps of Engineers
  TEL: 215-656-6690 Philadelphia District
  155.78.101.5 Hydraulics & Hydrology Branch
  johnd@nap61.nap.usace.army.mil
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