On Monday, 22 September 2025 16:50:08 British Summer Time Michael wrote: > I'll leave the awk scripting for dedup to more capable contributors, but if > this is an one-off problem it may be easier and quicker to run 'tar -tvf > somearchive.tgz | grep KMailFilters.txt' starting with the most recent > backup archives. At some point you'll come across an archive which has a > smaller KMailFilters.txt file size than the current file. Then you can > extract and diff that file with your current version. > > My suggestion falls apart if the duplication of filters was not caused by a > single event, but has crept in progressively over the years. In this case a > deduplication script will be a better way to approach this.
It seems I made a mountain out of a molehill. The problem did look pretty bleak, but the very first backup I tried had what I wanted: a good set of 38 filters. So thank you for your contribution, and apologies for requesting it. I should have tried before going into text. -- Regards, Peter.
