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

       sendmail - an electronic mail transport agent

       sendmail [flags] [address ...]
       mailq [-v]

       Sendmail sends a message to one or more recipients, routing the message
       over whatever networks are necessary.  Sendmail does internetwork  for-
       warding as necessary 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  mes-
       sage  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.
       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'.

       -Ac    Use submit.cf even if the operation mode does  not  indicate  an
	      initial 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

       -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  lis-
	      tening on socket 25 for incoming SMTP connections.  This is nor-
	      mally 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

       -bv    Verify  names only - do not try to collect or deliver a message.
	      Verify mode is normally used for	validating  users  or  mailing

       -Cfile Use   alternate  configuration  file.   Sendmail	gives  up  any
	      enhanced (set-user-ID or set-group-ID) privileges if  an	alter-
	      nate configuration file is specified.

       -D logfile
	      Send  debugging output to the indicated log file instead of std-

	      Set the debugging flag  for  category  to	 level.	  Category  is
	      either  an  integer or a name specifying the topic, and level an
	      integer  specifying  the	level  of  debugging  output  desired.
	      Higher  levels  generally	 mean more output.  More than one flag
	      can be specified by separating them  with	 commas.   A  list  of
	      numeric debugging categories can be found in the TRACEFLAGS file
	      in the sendmail source distribution.
	      The option -d0.1 prints the version of sendmail and the  options
	      it was compiled with.
	      Most  other  categories are only useful with, and documented in,
	      sendmail's source code.

	      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	 enve-
	      lope sender address is used as the recipient for delivery status
	      notifications and may also appear in a Return-Path: header.   -f
	      should 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.  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  specified,  ``Received:''  lines	 in  the  message  are

       -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 message 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
	      character names only.  The short names are not described in this
	      manual  page;  see the Sendmail Installation and Operation Guide
	      for details.

	      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
	      hostname, such as ``UUCP:ucbvax''.

	      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 back-
	      ground.  This option can be used safely with -bd.

	      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.

	      Process jobs in queue group called name only.

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

	      Limit  processed jobs to quarantined jobs containing substr as a
	      substring of the quarantine reason or not when !	is specified.

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

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

	      Quarantine a normal queue items with the given reason or unquar-
	      antine  quarantined  queue  items	 if  no reason is given.  This
	      should only be used with some sort of  item  matching  using  as
	      described above.

       -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
	      before 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

       -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.

       There  are  also	 a number of processing options that may be set.  Nor-
       mally these will only be used by a system administrator.	  Options  may
       be  set either 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:

	      Use alternate alias file.

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

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

	      Set the delivery mode to x.  Delivery modes are `i' for interac-
	      tive (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.

	      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 directory.

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

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

	      Do  not  take dots on a line by themselves as a message termina-

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

	      Set connection cache timeout.

	      Set connection cache size.

	      The log level.

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

	      Validate	the  right hand side of aliases during a newaliases(1)

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

	      Select the directory in which to queue messages.

	      Save statistics in the named file.

	      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 five days.

	      If  set, a user database is consulted to get forwarding informa-
	      tion.  You can consider this an adjunct to the  aliasing	mecha-
	      nism,  except  that  the database is intended to be distributed;
	      aliases are local to a particular host.  This may not be	avail-
	      able  if	your sendmail does not have the USERDB option compiled

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

	      Strip incoming messages to seven bits.

	      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.

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

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

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

	      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 recipi-
	      ents, add-apparently-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-recipi-

	      Sets the maximum number of children that an incoming SMTP daemon
	      will allow to spawn at any time to 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
       defined in <sysexits.h>:

       EX_OK  Successful completion on all addresses.

	      User name not recognized.

	      Catchall meaning necessary resources were not available.

	      Syntax error in address.

	      Internal software error, including bad arguments.

	      Temporary operating system error, such as ``cannot fork''.

	      Host name not recognized.

	      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 contents of the  mail	queue.
       If  invoked as hoststat, sendmail will print the persistent host status
       database.  If invoked as purgestat, sendmail will purge expired entries
       from  the  persistent host status database.  If invoked as smtpd, send-
       mail will act as a daemon, as if the -bd option were specified.

       sendmail often gets blamed for many  problems  that  are	 actually  the
       result  of  other problems, such as overly permissive modes on directo-
       ries.  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 Dont-
       BlameSendmail  option,  the  permission	problems should be fixed.  For
       more information, see:


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

	      raw data for alias names

	      data base of alias names

	      configuration file

	      help file

	      collected statistics

	      temp files

       mail(1), rmail(1), syslog(3), aliases(5), mailaddr(7),

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


       US Patent Numbers 6865671, 6986037.

       The sendmail command appeared in 4.2BSD.

			 $Date: 2009/04/10 17:49:19 $		   SENDMAIL(8)