sendmail (ADMN)


     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 forwarding 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  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.  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 even if the operation mode does not indi-
          cate an initial mail submission.

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

          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  back-
          ground   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

     -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  stan-
          dard input and output. This flag implies all the opera-
          tions 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.

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

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

          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 out-
          put.  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  docu-

          mented in, sendmail's source code.

          Set the full name of the sender.

          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 dur-
          ing initial submission.  The envelope 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  sup-
          plied 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  character  names  only. The short names are not
          described in this manual page; see the Sendmail Instal-
          lation and Operation Guide for details.

          Set the name of the protocol used to receive  the  mes-
          sage.  This  can  be  a  simple  protocol  name such as
          ``UUCP''  or  a  protocol   and   hostname,   such   as

          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.

     -qG name
          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

          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 unquarantine 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.

          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.

     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 (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

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

          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.

          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

          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

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

          Set connection cache timeout.

          Set connection cache size.

          The log level.

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

          Validate the  right  hand  side  of  aliases  during  a
          newaliases(ADMN) command.

          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

          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
          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 par-
          ticular host. This may not be available if  your  send-
          mail does not have the USERDB option compiled in.

          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 desti-
          nations  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

          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 recipients, 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-

          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 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 what it did.  The
     codes are defined in <sysexits.h>:

          Successful completion on all addresses.

          User name not recognized.

          Catchall meaning necessary resources  were  not  avail-

          Syntax error in address.

          Internal software error, including bad arguments.

          Temporary operating  system  error,  such  as  ``cannot

          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 con-
     tents 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  speci-


     sendmail often gets blamed for many problems that are  actu-
     ally 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 DontBlameSend-
     mail option, the permission problems should be  fixed.   For
     more information, see:


     Except  for  the  file  /etc/mail/   itself   the
     following     pathnames     are     all     specified     in
     /etc/mail/  Thus, these values are only approxi-

          raw data for alias names

          data base of alias names

          configuration file

          help file

          collected statistics

          temp files



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


     The sendmail command appeared in 4.2BSD.

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