Rule Set 2
All recipient addresses are rewritten by rule set 2
and the R=
of
delivery agents. But in almost all configuration
files, rule set 2 is unused because no processing is
needed:
# Recipient processing: none needed S2
But note that rule set 2 can be used to debug rules.[265] Consider the following rule in rule set 2 (that requires V8.9 and above sendmail to work):
R $# $+ $: $+ $:$2 Strip delivery agent and host when debugging
Recall that the parse
rule set 0 returns a triple. When
testing an address, rule set 2 can be called
following the parse
rule set 0 to simulate the
rewriting of the user portion of the parse
rule set 0. Here
the LHS matches only a triple, so normal recipient
addresses are unaffected. The user part that is
returned by the RHS can then be used to test
individual R=
rules of delivery agents. (Another technique is to
use the /try
command in -bt
rule-testing mode; see Try a Delivery Agent with /try
on page 313.)
See LOCAL_RULE_2 (LOCAL_RULE_1 and LOCAL_RULE_2 mc macros on page 596) for a way to add rules to rule set 2.
[265] * This is a truly
bogus example. We are really stretching to find a
use for rule set 2. There is no reason to do this
debugging in rule set 2 because rule set 99 would
work just as well. According to Eric, “I can think
of no good reason to use S2
today.”
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