Name
$s
Synopsis
The $s
macro contains the
name of the sender’s machine (host).
$s
is given the name of the local host as its
value when sendmail starts, unless the
-p
command-line switch (-p) is used, in which case $s
is given the value specified by that switch. Thereafter,
$s
is given a new value by
sendmail only if the mail message was received
via SMTP. For bounced mail, the $s
value is always
localhost
.
The s
macro is intended for use in the
Received
: header definition:
HReceived: $?sfrom $s $.by $j$?r with $r$. id $i
The phrase from
host will be
included in this header line if $s
has any value.
Here, host is the name of the sending machine.
The value in $s
is saved to the
qf
file when the mail message is queued and
restored to $s
when the queue is later processed.
$s
is transient. It can be defined on the command
line but should not be defined in the configuration file. Note that a
$&
prefix is necessary when you reference this
macro in rules (that is, use $&s
, not
$s
).
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