Andrew wrote (2022-01-20):

 >>> BinkD (the original implementation of BinkP) has always used \x##
 >>> as far as I know.

 RS>> BinkD was changed to *accept* '\##' however, back in 2002:
 RS>> https://github.com/pgul/binkd/commit/b4e7b17b7f0621abc1b3017307dd1382e
 RS>> aa039d9

 AL> That explains why when James tested against BinkD it had no issues with
 AL> him using \##.

And I think adding that workaround for broken mailers was a mistake that brought us more incompatibilities. Or should have been only a temporary workaround and deprecated a few years later.

https://en.wikipedia.org/wiki/Robustness_principle#Criticism
https://datatracker.ietf.org/doc/html/draft-iab-protocol-maintenance

 AL> The most compatible way to do things is to accept both on incoming, while
 AL> sending using \x##, unless configured otherwise on a per node basis, or
 AL> when you detect you are connected to a known mailer that uses \## (Argus
 AL> or IRex.)

All the big drama for a single legacy mailer: Irex that hasn't been updated forever. Argus users can upgrade to Radius or Taurus (both abandonware). Mystic is actively developed and users should use the latest release.

Let's face it: closed source software that isn't developed anymore has to become obsolete in a communication network that evolves (even slowly). If you want to do it the old way, you can still use EMSI over TCP.

And it's only a problem with filenames that contains a whitespace character.

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