Duplicating 8.1.7 database to a scn

Hi,
I need to duplicate an Oracle 8.1.7 database to a given point in time. I have seen problems when trying to do this with the set command specifying a date, but I have done it using an scn number when I got the scn number from a duplication that did a full recovery.

If I stop all transactions in the database how do I find out what scn number to use? I have it in mind to archive the current log so that all of the changes are in the redo stream, will the most recent archive log give me the scn number and if so where do I get this information from.

Thanks

Pete

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