Each header line created for the bounced message is displayed with
two leading spaces. For example:
--- putheader, mailer = *file* ---
Return-Path: you
Then certain headers are excluded from the bounced mail message
header. Those with the H_CTE flag set (Section 25.6.5)
and either the MCIF_CVT8TO7 or MCIF_INMIME mci
flags set will have the text:
(skipped (content-transfer-encoding))
appended and that header will be skipped (excluded).
Any header that has both H_CHECK and H_ACHECK flags set and
doesn't have identical delivery agent flags set for
itself and its cached connection information will also be skipped:
(skipped)
All re-sent headers (those marked with H_RESENT) are also skipped:
(skipped (resent))
Return-receipt headers are also skipped:
(skipped (receipt))
If a Bcc: header (Bcc:) is
being skipped, this is printed:
(skipped -- bcc)
Finally, valueless headers are also skipped with this message:
(skipped -- null value)
Any headers that survive this skipping process are included in the
eventually delivered bounced message. Note that MIME headers are not
generated or displayed here (§-d43).