F=l (lowercase L)
Agent performs local (final) delivery All versions
The F=l
delivery
agent flag tells sendmail that
this delivery agent will be performing final
delivery (usually on the local machine). This
notification affects sendmail’s
behavior in five ways.
First, it enables the DSN notify-on-success mechanism.[297] That is, if the message were received via SMTP with the envelope:
RCPT To: <user@here.us.edu> NOTIFY=SUCCESS
or via the command line with a -Nsuccess
command-line
switch, sendmail (upon final
local delivery) returns to the original sender an
email message acknowledging receipt. This mechanism
should be used sparingly.
Second, the F=l
delivery agent flag allows
sendmail to ignore any host
part of the triple returned by the parse
rule set 0.
Ordinarily, the $@
operator must appear in the RHS for
all delivery agents selected. If no host is selected
by $@
,
sendmail prints this error
and bounces the message:
554 5.3.5 buildaddr: no host
But because the host is not always needed for final
delivery, the presence of the F=l
delivery agent flag
tells sendmail to silently
ignore a missing host part.
Third, the F=l
delivery agent flag influences how undeliverable
mail will be handled. When the ErrorMode
option (ErrorMode on page 1028) is q
(quiet), such mail is
usually reported in the
sendmail program’s
exit(2) status (sendmail’s exit( ) Status on
page 228). With the F=l
delivery agent flag set for the envelope sender address, the undeliverable message will instead be appended to ...
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