F=M
Need Message-ID: in header All versions
The F=M
delivery
agent flag is used by
sendmail.cf header commands
to force the inclusion of message identification
information (F= on page
743):
H?M?Resent-Message-ID: <$t.$i@$j> H?M?Message-ID: <$t.$i@$j>
The F=M
delivery
agent flag has no special internal meaning to
sendmail. It is a convention
that is used only in the assorted Message-ID
: (Message-ID: on page 1159) header
definitions. See F= on page
743 for a general description of this
process.
Note that the Message-ID
: header definition should
always be included in the
sendmail.cf file because many
software packages expect the presence of that
header.
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