On Thu, 15 Jul 1999, Marilyn Davis wrote:
> So, does this mean sendmail is inconsistent about that leading '\n'?
Looks like it. However, it is not actually breaking any rules:
(1) The SMTP interface appears to be following the RFCs precisely; a
leading '\n' (or, actually '\r\n' in SMTP) is not being ignored - it is
terminating the headers.
(2) The specification of the command line interface between an MTA and
some other process that is calling it is not laid down in any standard
that I know of. Sendmail was first, and everybody else has just tried to
imitate it so that the same MUAs continue to work. It is within
Sendmail's rights to say "the message is passed on the standard input in
RFC 822 format, except that leading blank lines are ignored". In fact,
it already interprets "From " lines at the start of such messages (as
does Exim) so perhaps the leading blank skipping is all part of that
process, though it may not be deliberate, of course.
It would be very nice if somebody produced a formal, MTA-independent
definition of the MUA-MTA interface, and all us MTA implementors agreed
to stick with it, but it's probably too late now.
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.