Umm.. Tony? I hate to say it, but if there have been several variants used in
the wild, and the man pages for said variants document different formats,
that's awfully close to "anecdotally defined" when you're doing a standard.
The claim in Appendix A is that there were no authoritative sources of
documentation for the mbox formats and otherwise it's "only documented
in anecdotal form". I'm sorry, but the the definitions ARE there, and
ARE almost always authoritative for those systems.
This doesn't preclude there being other formats in the wild, nor does it
preclude there being other tools on those same machines that conflict.
For example, a Solaris 8 box across the hall says in 'man mail.local':
Any doubts that this whole mess is at best anecdotally defined can be dispelled
mentioning "Content-Length:" (interestingly enough, not even mentioned in the
Solaris or Sendmail man pages, although the Sendmail source tree does mention
that building on Solaris 2.3 or later will turn it on. Of interest mostly
the Content-Length: is so easily broken by later >-stuffing/unstuffing or other
Because Solaris 8 is System Vr4-derived, you should look at 'man mail'
for the definitive definition. You'll find Content-Length: documented there.
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