Name
${if_family_out}
Synopsis
The sendmail program
can send SMTP email over one or more network interfaces, where each
interface can have one or more addresses associated with it. When
sendmail sends a network email message, it
begins by connecting to a host on the network. Once that connection
has been made (once the other site accepts the connection),
sendmail records in the
${if_addr_out}
macro the address associated with
the interface over which it made that outbound connection. It then
records the family to which that address belongs in the
${if_family_out}
macro. The family is a text
representation of an integer value that represents the family, as
defined in sys/socket.h. A value of 2, for
example, could represent the AF_INET family.
${if_family_out}
is available for use in rule
sets, and can be useful for rejecting spam or restricting connections
to particular addresses. Note that a $&
prefix
is necessary when you reference this macro in rules (that is, use
$&{if_family_out}
, not
${if_family_out}
).
${if_family_out}
is transient. If it is defined in
the configuration file or in the command line, that definition can be
ignored by sendmail.
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