multipart/mixed; boundary="outer"
--outer
multipart/mixed; boundary="outer-inner"
--outer-inner
[...]
I have a vendor claiming that this is illegal because the "outer" appears
in the boundary "outer-inner", and thus violates the need for the
boundaries to be unique. Their claim is in fact that "outer" must appear
NOWHERE in the body--not merely that "--outer<CRLF>" must not appear in the
body.
I think this is absolutely preposterous. I think that the uniqueness
requirement means that the string "--outer<CRLF>" must not appear as body
contents ...
I agree that it's preposterous, but have one small correction: as I interpret
it, there are two strings which must not appear as body contents:
"<CRLF>--outer"
"<CRLF>--outer--"
The RFC speaks explicitly about the preceding CRLF being conceptually attached
to the boundary string, but merely states that the boundary string "must be
followed by another CRLF".
---glv