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SENDMAIL(8)							   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  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'.

   Parameters
       -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
	      8BITMIME.

       -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
	      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  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-
	      out.

       -dcategory.level...
	      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.

       -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 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
	      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 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.

       -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
	      hostname, 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 back-
	      ground.  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.

       -qGname
	      Process jobs in queue group called name only.

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

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

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

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

       -Q[reason]
	      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
	      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.  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:

       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
	      (default 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 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.

       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 directory.

       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 termina-
	      tor.

       SendMimeErrors
	      Send error messages in MIME format.  If not set, the DSN (Deliv-
	      ery 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)
	      command.

       OldStyleHeaders
	      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.

       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
	      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.

       UserDatabaseSpec=userdatabase
	      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
	      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  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-
	      ents:;'.

       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
       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 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.

NOTES
       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:

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

FILES
       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.


	/etc/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

	/var/log/mail/statistics
	      collected statistics

	/var/spool/mqueue/*
	      temp files

SEE ALSO
       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.

       http://www.sendmail.org/

HISTORY
       The sendmail command appeared in 4.2BSD.



			 $Date: 2003/12/01 17:02:41 $		   SENDMAIL(8)
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