sendmail(8) INTERACTIVE UNIX System sendmail(8)
NAME
sendmail - send mail over the internet
SYNOPSIS
/usr/lib/sendmail [ flags ] [ address ... ]
newaliases
mailq [ -v ]
DESCRIPTION
The sendmail program sends a message to one or more reci-
pients, routing the message over whatever networks are
necessary. sendmail does internetwork forwarding as neces-
sary to deliver the message to the correct place.
sendmail is not intended as a user interface routine. Other
programs provide user-friendly front ends; sendmail is used
only to deliver pre-formatted messages.
With no flags, sendmail reads its standard input up to an
end-of-file or a line consisting only of a single dot and
sends a copy of the message found there to all of the
addresses listed. It determines the network(s) to use based
on the syntax and contents of the addresses.
Local addresses are looked up in a file and aliased
appropriately. Aliasing can be prevented by preceding the
address with a backslash (\). Normally, the sender is not
included in any alias expansions, e.g., if john sends to
group, and group includes john in the expansion, then the
letter will not be delivered to john.
The options to sendmail are:
-ba Go into ARPANET mode. All input lines must end
with a carriage return/line-feed, and all mes-
sages will be generated with a carriage
return/line-feed at the end. Also, the
``From:'' and ``Sender:'' fields are examined
for the name of the sender.
-bd Run as a daemon. This requires that host-based
TCP/IP be installed. sendmail will fork and run
in background listening on socket 25 for incom-
ing SMTP connections. This is normally run from
/etc/rc3.d/S36sendmail.
-bi Initialize the alias database.
-bm Deliver mail in the usual way (default).
-bp Print a listing of the queue.
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sendmail(8) INTERACTIVE UNIX System sendmail(8)
-bs Use the simple mail transfer protocol (SMTP) as
described in RFC821 on standard input and out-
put. This flag implies all the operations of
the -ba flag that are compatible with SMTP.
-bt Run in address test mode. This mode reads
addresses and shows the steps in parsing; it is
used for debugging configuration tables.
-bv Verify names only - do not try to collect or
deliver a message. Verify mode is normally used
for validating users or mailing lists.
-bz Create the configuration freeze file.
-Cfile Use alternate configuration file. sendmail
refuses to run as root if an alternate confi-
guration file is specified. The frozen confi-
guration file is bypassed.
-dX Set debugging value to X.
-Ffullname Set the full name of the sender.
-fname Sets the name of the ``from'' person (i.e., the
sender of the mail). -f can only be used by
``trusted'' users (normally root, daemon, and
network ) or if the person you are trying to
become is the same as the person you are.
-hN Set the hop count to N. The hop count is incre-
mented every time the mail is processed. When
it reaches a limit, the mail is returned with an
error message, the victim of an aliasing loop.
If not specified, ``Received:'' lines in the
message are counted.
-n Do not do aliasing.
-oxvalue Set option x to the specified value. Options
are described below.
-q[time] Processed saved messages in the queue at given
intervals. If time is omitted, process the
queue once. The time variable is given as a
tagged number, with s being seconds, m being
minutes, h being hours, d being days, and w
being weeks. For example, ``-q1h30m'' or
``-q90m'' would both set the timeout to 1 hour
30 minutes. If time is specified, sendmail will
run in the background. This option can be used
safely with -bd.
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sendmail(8) INTERACTIVE UNIX System sendmail(8)
-rname An alternate and obsolete form of the -f flag.
-t Read message for recipients. To:, Cc:, and Bcc:
lines will be scanned for recipient addresses.
The Bcc: line will be deleted before transmis-
sion. Any addresses in the argument list will
be suppressed, that is, they will not receive
copies even if listed in the message header.
-v Go into verbose mode. Alias expansions will be
announced, etc.
There are also a number of processing options that may be
set. Normally these will only be used by a system adminis-
trator. Options may be set either on the command line using
the -o flag or in the configuration file. These are
described in detail in the ``Sendmail Installation and
Operation Guide.'' The options are:
Afile Use alternate alias file.
c On mailers that are considered ``expensive'' to
connect to, do not initiate immediate connec-
tion. This requires queueing.
dx Set the delivery mode to x. Delivery modes are
``i'' for interactive (synchronous) delivery,
``b'' for background (asynchronous) delivery,
and ``q'' for queue only - i.e., actual delivery
is done the next time the queue is run.
D Try to automatically rebuild the alias database
if necessary.
ex Set error processing to mode x. Valid modes are
``m'' to mail back the error message, ``w'' to
``write'' back the error message (or mail it
back if the sender is not logged in), ``p'' to
print the errors on the terminal (default),
``q'' to throw away error messages (only exit
status is returned), and ``e'' to do special
processing for the (obsolete) Berkeley Network.
If the text of the message is not mailed back by
modes ``m'' or ``w'' and if the sender is local
to this machine, a copy of the message is
appended to the file ``dead.letter'' in the
sender's home directory.
Fmode The mode to use when creating temporary files.
f Save UNIX System-style From lines at the front
of messages.
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sendmail(8) INTERACTIVE UNIX System sendmail(8)
gN The default group ID to use when calling
mailers.
Hfile The SMTP help file.
i Do not take dots on a line by themselves as a
message terminator.
Ln The log level.
m Send to ``me'' (the sender) also if I am in an
alias expansion.
o If set, this message may have old style headers.
If not set, this message is guaranteed to have
new style headers (i.e., commas instead of
spaces between addresses). If set, an adaptive
algorithm is used that will correctly determine
the header format in most cases.
Qqueuedir Select the directory in which to queue messages.
rtimeout The timeout on reads; if none is set, sendmail
will wait forever for a mailer. This option
violates the word (if not the intent) of the
SMTP specification, so the timeout should prob-
ably be fairly large.
Sfile Save statistics in the named file.
s Always instantiate the queue file, even under
circumstances where it is not strictly neces-
sary. This provides safety against system
crashes during delivery.
Ttime Set the timeout on undelivered messages in the
queue to the specified time. After delivery has
failed (e.g., because of a host being down) for
this amount of time, failed messages will be
returned to the sender. The default is 3 days.
tstz,dtz Set the name of the time zone.
uN Set the default user ID for mailers.
In aliases, the first character of a name may be a vertical
bar to cause interpretation of the rest of the name as a
command to pipe the mail to. It may be necessary to quote
the name to keep sendmail from suppressing the blanks from
between arguments. For example, a possible alias is:
msgs: "|/usr/ucb/msgs -s"
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sendmail(8) INTERACTIVE UNIX System sendmail(8)
Aliases may also have the syntax ``:include:filename'' to
ask sendmail to read the named file for a list of reci-
pients. For example, an alias such as:
poets: ":include:/usr/local/lib/poets.list"
would read /usr/local/lib/poets.list for the list of
addresses making up the group.
sendmail returns an exit status describing the disposition
of the mail. The codes are defined in <sysexits.h>
EX_OK Successful completion on all addresses.
EX_NOUSER User name not recognized.
EX_UNAVAILABLE Catchall meaning necessary resources
were not available.
EX_SYNTAX Syntax error in address.
EX_SOFTWARE Internal software error, including bad
arguments.
EX_OSERR Temporary operating system error, such
as cannot fork.
EX_NOHOST Host name not recognized.
EX_TEMPFAIL Message could not be sent immediately,
but was queued.
If invoked as newaliases, sendmail will rebuild the alias
database. If invoked as mailq, sendmail will print the con-
tents of the mail queue.
FILES
Except for /usr/lib/sendmail.cf, these path names are all
specified in /usr/lib/sendmail.cf. Thus, these values are
only approximations.
/usr/lib/aliases raw data for alias names
/usr/lib/aliases.pag
/usr/lib/aliases.dir
database of alias names
/usr/lib/sendmail.cf
configuration file
/usr/lib/sendmail.fc
frozen configuration
/usr/lib/sendmail.hf
help file
/usr/lib/sendmail.st
collected statistics
/usr/spool/mqueue/* temp files
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sendmail(8) INTERACTIVE UNIX System sendmail(8)
SEE ALSO
mail(1), mailx(1), rmail(1).
syslog(3), aliases(5) in the INTERACTIVE SDS Guide and
Programmer's Reference Manual.
DARPA Internet Request For Comments RFC819, RFC821, RFC822,
``Sendmail - An Internetwork Mail Router'' and ``Sendmail
Installation and Operation Guide'' in the INTERACTIVE UNIX
Operating System Guide.
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