Re: How to convert <binaryGlowMixedWithASCII> to pure ASCII

In comp.unix.shell, Lew Pitcher  <lew.pitcher@digitalfreehold.ca> wrote:

On Sun, 04 May 2025 18:15:38 +0000, Kenny McCormack wrote:

I have a string like (this was the "From" address of an email I recently received):
    =?utf-8?B?UGhpbGxpcCBHw7xudGVy?= <s69pguen@uni-bonn.de>

This is called a "MIME word" or "MIME encoded word" Mail headers are
supposed to be 7-bit clean even when mail bodies can have 8-bit
encodings. MIME words exist to put quoted-printable and base64 in
headers.

       =?utf-8?B?UGhpbGxpcCBHw7xudGVy?=
         ^^^^^ | ^^^^^^^^^^^^^^^^^^^^
       Charset | Content
               |
       Encoding: "B" for base64 "Q" for quoted-printable.

:r! echo UGhpbGxpcCBHw7xudGVy | base64 -d
Phillip Günter

    TF-8?q?They’re_telling_us_something_about_something_ok?

That one is rather mangled. It doesn't follow the =?%s?%c?%s?= format.
It also has a high-bit character in the content. But it does show the
quirk of MIME word quoted-printable: underscores used for spaces.

My question is: Is there a (Unix/Linux) tool that will reliably fix this?
I.e. convert the binary glop format into the desired, pure ASCII, format.

Your mail program should. I have seen Python and Perl libraries for
decoding, too. Knowing the name should help you find them.

What you are looking at is the "punycode"[1] expression of a
non-ASCII character sequence.

No. Punycode is a entirely different coding used to put highbit content
in domain names (DNS). It is not base64 based.

https://en.wikipedia.org/wiki/MIME#Encoded-Word
https://en.wikipedia.org/wiki/Punycode

As an example "Günter.com" encodes in Punycode as: xn--Gnter-kva.com

Someone has that registered, but it is blank in my browser.

Elijah
------
thinks Günter probably likes his name with the accent and not "pure ASCII"