Thanks to both Eric and Steve for the advice.  I'll have a whack.
slow is ok --- I shouldn't be doing this too often!

R

_______________________________________________
TCLUG Mailing List - Minneapolis/St. Paul, Minnesota
http://www.mn-linux.org tclug-list at mn-linux.org
https://mailman.real-time.com/mailman/listinfo/tclug-list