${mail_host}
Saved $@ value for MAIL From: triple V8.10 and later
Upon receipt of the MAIL
From:
address, a delivery agent is
selected by the RHS of a parse
rule set 0 rule, which defines a
triple that contains three pieces of information for
that address:
$#delivery_agent $@ host $:address
The $@
portion of
the triple contains the host to which to connect for
delivery. For example:
wash.dc.gov
Once that host is determined for the $@
part of the triple,
it is copied to this ${mail_host}
macro.
${mail_host}
is
transient. If it is defined in the configuration
file or in the command line, that definition can be
ignored by sendmail. Note that
a $&
prefix
is necessary when you reference this macro in rules
(that is, use $&{mail_host}
, not ${mail_host}
).
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