Sendmail Installation and Operation Guide
SMM:08-57
5
If no aliases are found for this address, pass the address through ruleset 5 for possible alternate
resolution. This is intended to forward the mail to an alternate delivery spot.
6
Strip headers to seven bits.
7
Strip all output to seven bits. This is the default if the L flag is set. Note that clearing this
option is not sufficient to get full eight bit data passed through sendmail. If the 7 option is set,
this is essentially always set, since the eighth bit was stripped on input. Note that this option
will only impact messages that didn't hav e 8
7 bit MIME conversions performed.
8
If set, it is acceptable to send eight bit data to this mailer; the usual attempt to do 8
7 bit
MIME conversions will be bypassed.
9
If set, do limited 7
8 bit MIME conversions. These conversions are limited to text/plain data.
:
Check addresses to see if they begin ":include:"; if they do, convert them to the "*include*"
mailer.
|
Check addresses to see if they begin with a `|'; if they do, convert them to the "prog" mailer.
/
Check addresses to see if they begin with a `/'; if they do, convert them to the "*file*" mailer.
@
Look up addresses in the user database.
%
Do not attempt delivery on initial recipient of a message or on queue runs unless the queued
message is selected using one of the -qI/-qR/-qS queue run modifiers or an ETRN request.
Configuration files prior to level 6 assume the `A', `w', `5', `:', `|', `/', and `@' options on the
mailer named "local".
The mailer with the special name "error" can be used to generate a user error. The (optional)
host field is an exit status to be returned, and the user field is a message to be printed. The exit sta-
tus may be numeric or one of the values USAGE, NOUSER, NOHOST, UNAVAILABLE, SOFT-
WARE, TEMPFAIL, PROT OCOL, or CONFIG to return the corresponding EX_ exit code, or an
enhanced error code as described in RFC 1893, Enhanced Mail System Status Codes. For example,
the entry:
$#error $@ NOHOST $: Host unknown in this domain
on the RHS of a rule will cause the specified error to be generated and the "Host unknown" exit sta-
tus to be returned if the LHS matches. This mailer is only functional in rulesets 0, 5, or one of the
check_* rulesets. The host field can also contain the special token quarantine which instructs
sendmail to quarantine the current message.
The mailer with the special name "discard" causes any mail sent to it to be discarded but oth-
erwise treated as though it were successfully delivered. This mailer cannot be used in ruleset 0,
only in the various address checking rulesets.
The mailer named "local" must be defined in every configuration file. This is used to deliver
local mail, and is treated specially in several ways. Additionally, three other mailers named "prog",
"*file*", and "*include*" may be defined to tune the delivery of messages to programs, files, and
:include: lists respectively. They default to:
Mprog, P=/bin/sh, F=lsoDq9, T=DNS/RFC822/X-Unix, A=sh -c $u
M*file*, P=[FILE], F=lsDFMPEouq9, T=DNS/RFC822/X-Unix, A=FILE $u
M*include*, P=/dev/null, F=su, A=INCLUDE $u
Builtin pathnames are [FILE] and [IPC], the former is used for delivery to files, the latter for
delivery via interprocess communication. For mailers that use [IPC] as pathname the argument vec-
tor (A=) must start with TCP or FILE for delivery via a TCP or a Unix domain socket. If TCP is
used, the second argument must be the name of the host to contact. Optionally a third argument can
be used to specify a port, the default is smtp (port 25). If FILE is used, the second argument must
be the name of the Unix domain socket.