Batch conversion from "normal" Unicode text to NCRs

[António MARTINS-Tuválkin]

Okay, sorry, it’s not even really a case of conversion, but mere a batch
job of save-as. Asking for a friend, litterally, as my own workflows are
set in stone and work perfectly for my needs, but this fellow has a
weekly load of a few hundred HTML files created by several people of
varying skill levels: Upon processing and ftp unloading (yes, this is an
old school website that is created/mantained via an offline tool and the
pages are static HTML documents) the resulting pages online present some
times wonky results, due to uneven inclusion of “high byte” characters.

I have been saying in the past couple decades that problems will vanish
if all files include only “ASCII characters”, by means of NCR escape
sequences, but some of the aforementioned individual editors seem unable
to ensure it, so a wholesale “conversion” is the intermediate step that
needs to be added to the workflow, before uploading.

And my question is: Which tool to use? The person in question is adept
enough to use command lines, and the files to be changed are in a single
folder; the working environment is Windows 11. (And that’s sadly why
[ https://sourceforge.net/projects/cp-converter/reviews/ ] is not the
answer, due to the issue with .NET 3.5 support.) Please help!

--                                                               ____.
António MARTINS-Tuválkin           Não me invejo de quem tem    |  ()|
<tuvalkin at gmail.com>               carros, parelhas e montes    |####|
PT-2695-016 + PT-2745-318          só me invejo de quem bebe         |
+351 934 821 700                   a água em todas as fontes         |
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De sable uma fonte e bordadura escaqueada de jalde e goles, por timbre
a bandeira, por mote o 1º verso acima, e grito de guerra "Mi rajtas!".
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