$b
The current date in RFC2822 format All versions
The $b
macro
contains the current date in ARPAnet format, as
defined in RFC822, Support SMTP AUTH, and amended by RFC2822, Pitfalls.
Because $b
holds
the current date and time,
sendmail frequently updates
the value in that macro. When
sendmail first starts to run,
it places the current date and time into $b
. Thereafter, each
time an SMTP connection is made and each time the
queue is processed, the value of the date and time
in that macro is updated.
If the system call to time(3)
should fail, the value stored in $b
becomes Wed Dec 31
15:59:59 1969,[314] and no other indication of an error is
given.
$b
is chiefly
intended for use in configuration-file header
definitions that require ARPAnet format (such as
Received
:,
Received: on page
1162).
$b
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 $&b
, not $b
).
[314] * The actual time depends on the local time zone.
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