The date/time stamp on the archive file may be enough, as holi remarked. I find it useful to store the date, preferrably as part of the file name (as nmdokk suggested) since copying can destroy the original date. Personally I always use the number of seconds since epoc, rather than a "display" date format. It is then much easier to compare with other dates in the same format.
This is the same format used by most file systems, and is returned by stat. You can also get a similar number from time, but don't mix them.

In reply to Re: Seeking help on a backup script by cdarke
in thread Seeking help on a backup script by Anonymous Monk

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