Thanks Fastolfe, for an informative reply, also to japhy, geektron, and I think tilly in the Chattbox.

Actually, I'm looking for unique strings that happen to be hostnames.   The list is built using a variation of (code)) Cisco Pass Mass - IOS (deprecated by node 123464) to query a core switch for CDP neighbors (wiring closet "top o' stack" switches).   Next I feed the output back into the same script to find remaining switches in each wiring closet stack.   Then, I'll feed the complete list of core+closet switches back into the original (code)) Cisco Pass Mass - IOS (deprecated by node 123464) script to implement my config updates.

I've now got my hands on the Perl Cookbook, pouring over example 4.6.   Looks like I'm getting closer to a solution.   Keys of Hash, eh?
    cheers,
    ybiC

In reply to RE: (2) extract uniques and sort (thanks, getting closer)) by ybiC
in thread extract uniques and sort by ybiC

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