The final Rule Set 4
Just as all
addresses are first rewritten by the canonify
rule
set 3, so are all addresses rewritten last by the
final
rule set 4. Beginning with V8.10
sendmail, that rule set is declared like this:
Sfinal=4
As the name final
implies, the job is to undo any
special processing done by the canonify
rule set
3, such as focusing. In this section we’ll examine
some typical final
rule set 4 rules.
Stripping Trailing Dots
Under some versions of sendmail a successful conversion to a fully qualified domain name leaves an extra dot trailing the result. This rule strips that dot:
# strip trailing dot off possibly canonical name R $* <@ $+. > $* $1 <@ $2 > $3
Note that this rule recursively removes as many trailing dots as it finds. Also note that the host part remains focused after rewriting.
Restoring Source Routes
Recall that the canonify
rule set 3 converted the
commas of source route addresses into colons (Section 19.3.3). The final
rule set 4 now
needs to restore those commas:
R $* : $+ :$+ <@ $+> $1 , $2 : $3 <@ $4> <route-addr> canonical
This rule recursively changes all but one (the rightmost) colon back into a comma.
As a special note, under V8 sendmail,
envelope-sender route addresses are always surrounded by angle
brackets when passed to the delivery agent. If this behavior is
inappropriate for your site, beginning with V8.7 it is possible to
prevent this heuristic by specifying the F=d
delivery agent flag (F=d).
Removing Focus
The final
rule set 4 also removes angle ...
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