${client_ptr}
Connecting client’s PTR record V8.13 and later
When a client host connects to the listening sendmail server, that
server knows the IP address of the connecting client
but not its hostname. To find the hostname,
sendmail
performs a reverse lookup to find a PTR record which
contains the host’s name. Beginning with V8.13, the
result of that lookup (the host’s name) is stored in
the ${client_ptr}
macro.
Note that if (and only if) the ${client_resolve} macro
(${client_resolve}
on page 814) contains a literal OK, will this ${client_ptr} macro hold
the same value that the ${client_name} macro (${client_name} on page 812) holds.
${client_ptr} 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 $&{client_ptr}, not ${client_ptr}).
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