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SENDMAIL(8)		     System Manager's Manual		     SENDMAIL(8)

NAME
     sendmail - an electronic mail transport agent

SYNOPSIS
     sendmail [flags] [address ...]
     newaliases
     mailq [-v]
     hoststat
     purgestat
     smtpd

DESCRIPTION
     Sendmail  sends  a  message  to one or more recipients, routing the message
     over whatever networks are necessary.  Sendmail does internetwork	forward-
     ing as necessary to deliver the message to the correct place.

     Sendmail  is  not intended as a user interface routine; other programs pro-
     vide user-friendly front ends; sendmail is used only to deliver pre-format-
     ted 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.  Alias-
     ing can be prevented by preceding the address with a backslash.   Beginning
     with  8.10, the sender is included in any alias expansions, e.g., if `john'
     sends to `group', and `group' includes `john' in the  expansion,  then  the
     letter will also be delivered to `john'.

   Parameters
     -Ac    Use  submit.cf  even if the operation mode does not indicate an ini-
	    tial mail submission.

     -Am    Use sendmail.cf even if the operation mode indicates an initial mail
	    submission.

     -Btype
	    Set the body type to type.	Current legal values are 7BIT  or  8BIT-
	    MIME.

     -ba    Go	into  ARPANET  mode.  All input lines must end with a CR-LF, and
	    all messages will be generated with a CR-LF at the end.   Also,  the
	    ``From:''  and  ``Sender:''  fields are examined for the name of the
	    sender.

     -bd    Run as a daemon.  Sendmail will fork and run in background listening
	    on socket 25 for incoming SMTP connections.  This  is  normally  run
	    from /etc/rc.

     -bD    Same as -bd except runs in foreground.

     -bh    Print the persistent host status database.

     -bH    Purge expired entries from the persistent host status database.

     -bi    Initialize the alias database.

     -bm    Deliver mail in the usual way (default).

     -bp    Print a listing of the queue(s).

     -bP    Print  number of entries in the queue(s); only available with shared
	    memory support.

     -bs    Use the SMTP protocol as described in RFC821 on standard  input  and
	    output.   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.

     -Cfile
	    Use alternate configuration file.  Sendmail refuses to run	as  root
	    if an alternate configuration file is specified.

     -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 envelope sender of
	    the mail).	This address may also be used in  the  From:  header  if
	    that  header  is  missing  during  initial submission.  The envelope
	    sender address is used as the recipient for delivery status  notifi-
	    cations  and  may  also  appear in a Return-Path: header.  -f should
	    only be used by ``trusted'' users (normally root, daemon,  and  net-
	    work)  or  if the person you are trying to become is the same as the
	    person you are.  Otherwise, an X-Authentication-Warning header  will
	    be added to the message.

     -G     Relay  (gateway)  submission  of  a  message, e.g., when rmail calls
	    sendmail .

     -hN    Set the hop count to N.  The hop count is incremented 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 spec-
	    ified, ``Received:'' lines in the message are counted.

     -i     Ignore dots alone on lines by themselves in incoming messages.  This
	    should be set if you are reading data from a file.

     -L tag
	    Set the identifier used in syslog messages to the supplied tag.

     -N dsn
	    Set  delivery  status  notification  conditions to dsn, which can be
	    `never' for no notifications or a comma separated list of the values
	    `failure' to be notified if delivery failed, `delay' to be	notified
	    if	delivery  is delayed, and `success' to be notified when the mes-
	    sage is successfully delivered.

     -n     Don't do aliasing.

     -O option=value
	    Set option option to the  specified  value.   This	form  uses  long
	    names.  See below for more details.

     -ox value
	    Set  option x to the specified value.  This form uses single charac-
	    ter names only.  The short names are not described	in  this  manual
	    page; see the Sendmail Installation and Operation Guide for details.

     -pprotocol
	    Set  the name of the protocol used to receive the message.	This can
	    be a simple protocol name such as ``UUCP'' or a protocol  and  host-
	    name, such as ``UUCP:ucbvax''.

     -q[time]
	    Process  saved messages in the queue at given intervals.  If time is
	    omitted, process the queue once.  Time is given as a tagged  number,
	    with  `s'  being  seconds,	`m'  being  minutes (default), `h' being
	    hours, `d' being days, and `w' being weeks.  For example,  `-q1h30m'
	    or	`-q90m'  would	both set the timeout to one hour thirty minutes.
	    By default, sendmail will run in the background.  This option can be
	    used safely with -bd.

     -qp[time]
	    Similar to -qtime, except that instead  of	periodically  forking  a
	    child to process the queue, sendmail forks a single persistent child
	    for  each  queue  that  alternates	between processing the queue and
	    sleeping.  The sleep time is given as the argument; it defaults to 1
	    second.  The process will always sleep at least  5	seconds  if  the
	    queue was empty in the previous queue run.

     -qf    Process  saved messages in the queue once and do not fork(), but run
	    in the foreground.

     -qG name
	    Process jobs in queue group called name only.

     -q[!]I substr
	    Limit processed jobs to those containing substr as	a  substring  of
	    the queue id or not when !	is specified.

     -q[!]R substr
	    Limit  processed  jobs  to those containing substr as a substring of
	    one of the recipients or not when !  is specified.

     -q[!]S substr
	    Limit processed jobs to those containing substr as	a  substring  of
	    the sender or not when !  is specified.

     -R return
	    Set the amount of the message to be returned if the message bounces.
	    The  return  parameter can be `full' to return the entire message or
	    `hdrs' to return only the headers.	In the latter  case  also  local
	    bounces return only the headers.

     -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  be-
	    fore transmission.

     -V envid
	    Set  the  original	envelope  id.  This is propagated across SMTP to
	    servers that support DSNs and is  returned	in  DSN-compliant  error
	    messages.

     -v     Go into verbose mode.  Alias expansions will be announced, etc.

     -X logfile
	    Log  all  traffic  in  and out of mailers in the indicated log file.
	    This should only be used as a last resort for debugging mailer bugs.
	    It will log a lot of data very quickly.

     --     Stop processing command flags and use the rest of the  arguments  as
	    addresses.

   Options
     There  are  also  a number of processing options that may be set.	Normally
     these will only be used by a system administrator.  Options may be set  ei-
     ther  on  the command line using the -o flag (for short names), the -O flag
     (for long names), or in the configuration file.  This  is	a  partial  list
     limited  to  those options that are likely to be useful on the command line
     and only shows the long names; for a complete list (and  details),  consult
     the Sendmail Installation and Operation Guide.  The options are:

     AliasFile=file
	    Use alternate alias file.

     HoldExpensive
	    On	mailers  that  are considered ``expensive'' to connect to, don't
	    initiate immediate connection.  This requires queueing.

     CheckpointInterval=N
	    Checkpoint the queue file after every N successful	deliveries  (de-
	    fault  10).  This avoids excessive duplicate deliveries when sending
	    to long mailing lists interrupted by system crashes.

     DeliveryMode=x
	    Set the delivery mode to x.  Delivery modes are `i' for  interactive
	    (synchronous)  delivery, `b' for background (asynchronous) delivery,
	    `q' for queue only - i.e., actual delivery is done the next time the
	    queue is run, and `d' for deferred - the same  as  `q'  except  that
	    database  lookups for maps which have set the -D option (default for
	    the host map) are avoided.

     ErrorMode=x
	    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
	    BerkNet.  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 di-
	    rectory.

     SaveFromLine
	    Save UNIX-style From lines at the front of messages.

     MaxHopCount=N
	    The maximum number of times a message is allowed to  ``hop''  before
	    we decide it is in a loop.

     IgnoreDots
	    Do not take dots on a line by themselves as a message terminator.

     SendMimeErrors
	    Send  error  messages in MIME format.  If not set, the DSN (Delivery
	    Status Notification) SMTP extension is disabled.

     ConnectionCacheTimeout=timeout
	    Set connection cache timeout.

     ConnectionCacheSize=N
	    Set connection cache size.

     LogLevel=n
	    The log level.

     MeToo=False
	    Don't send to ``me'' (the sender) if I am in an alias expansion.

     CheckAliases
	    Validate the right hand side of aliases during a newaliases(1)  com-
	    mand.

     OldStyleHeaders
	    If	set,  this message may have old style headers.	If not set, this
	    message is guaranteed to have new style headers  (i.e.,  commas  in-
	    stead  of  spaces between addresses).  If set, an adaptive algorithm
	    is used that will correctly determine  the	header	format	in  most
	    cases.

     QueueDirectory=queuedir
	    Select the directory in which to queue messages.

     StatusFile=file
	    Save statistics in the named file.

     Timeout.queuereturn=time
	    Set  the  timeout on undelivered messages in the queue to the speci-
	    fied 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 five days.

     UserDatabaseSpec=userdatabase
	    If	set, a user database is consulted to get forwarding information.
	    You can consider this an adjunct to the aliasing  mechanism,  except
	    that  the  database is intended to be distributed; aliases are local
	    to a particular host.  This may not be available  if  your	sendmail
	    does not have the USERDB option compiled in.

     ForkEachJob
	    Fork  each	job during queue runs.	May be convenient on memory-poor
	    machines.

     SevenBitInput
	    Strip incoming messages to seven bits.

     EightBitMode=mode
	    Set the handling of eight bit input to  seven  bit	destinations  to
	    mode:  m  (mimefy)	will  convert to seven-bit MIME format, p (pass)
	    will pass it as eight bits (but violates protocols), and s	(strict)
	    will bounce the message.

     MinQueueAge=timeout
	    Sets  how  long  a job must ferment in the queue between attempts to
	    send it.

     DefaultCharSet=charset
	    Sets the default character set used to label 8-bit data that is  not
	    otherwise labelled.

     DialDelay=sleeptime
	    If	opening  a connection fails, sleep for sleeptime seconds and try
	    again.  Useful on dial-on-demand sites.

     NoRecipientAction=action
	    Set the behaviour when there are no recipient headers (To:,  Cc:  or
	    Bcc:)  in  the message to action: none leaves the message unchanged,
	    add-to adds a To: header with the  envelope  recipients,  add-appar-
	    ently-to adds an Apparently-To: header with the envelope recipients,
	    add-bcc  adds  an  empty  Bcc: header, and add-to-undisclosed adds a
	    header reading `To: undisclosed-recipients:;'.

     MaxDaemonChildren=N
	    Sets the maximum number of children that  an  incoming  SMTP  daemon
	    will allow to spawn at any time to N.

     ConnectionRateThrottle=N
	    Sets  the  maximum number of connections per second to the SMTP port
	    to N.

     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 common alias is:

	    msgs: "|/usr/bin/msgs -s"

     Aliases may also have the syntax ``:include:filename'' to ask  sendmail  to
     read  the	named file for a list of recipients.  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 what it did.  The codes are de-
     fined 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 in-
     voked as mailq, sendmail will print the contents of the mail queue.  If in-
     voked as hoststat, sendmail will print the persistent host status database.
     If invoked as purgestat, sendmail will purge expired entries from the  per-
     sistent  host status database.  If invoked as smtpd, sendmail will act as a
     daemon, as if the -bd option were specified.

NOTES
     sendmail often gets blamed for many problems that are actually  the  result
     of  other	problems,  such  as overly permissive modes on directories.  For
     this reason, sendmail checks the modes on system directories and  files  to
     determine	if they can be trusted.  Although these checks can be turned off
     and your system security reduced by setting the  DontBlameSendmail  option,
     the permission problems should be fixed.  For more information, see:

     http://www.sendmail.org/tips/DontBlameSendmail.html

FILES
     Except  for  the  file /etc/mail/sendmail.cf itself the following pathnames
     are all specified in /etc/mail/sendmail.cf.  Thus, these  values  are  only
     approximations.

      /etc/mail/aliases
	    raw data for alias names

      /etc/mail/aliases.db
	    data base of alias names

      /etc/mail/sendmail.cf
	    configuration file

      /etc/mail/helpfile
	    help file

      /etc/mail/statistics
	    collected statistics

      /var/spool/mqueue/*
	    temp files

SEE ALSO
     mail(1), syslog(3), aliases(5), mailaddr(7), mail.local(8), rc(8), rmail(8)

     DARPA  Internet  Request For Comments RFC819, RFC821, RFC822.  Sendmail In-
     stallation and Operation Guide, No. 8, SMM.

     http://www.sendmail.org/

HISTORY
     The sendmail command appeared in 4.2BSD.

			  $Date: 2001/03/23 22:10:00 $		     SENDMAIL(8)
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