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<html> <head> </head> <body> <pre>

LOCAL(8)                                                 LOCAL(8)

<b>NAME</b>
       local - Postfix local mail delivery

<b>SYNOPSIS</b>
       <b>local</b> [generic Postfix daemon options]

<b>DESCRIPTION</b>
       The  <b>local</b>  daemon  processes  delivery  requests from the
       Postfix queue manager to deliver mail to local recipients.
       Each  delivery  request  specifies  a queue file, a sender
       address, a domain or host to deliver to, and one  or  more
       recipients.   This program expects to be run from the <a href="master.8.html"><b>mas-</b></a>
       <a href="master.8.html"><b>ter</b>(8)</a> process manager.

       The <b>local</b> daemon updates queue files and marks  recipients
       as finished, or it informs the queue manager that delivery
       should be tried again at a later  time.  Delivery  problem
       reports  are  sent  to the <a href="bounce.8.html"><b>bounce</b>(8)</a> or <a href="defer.8.html"><b>defer</b>(8)</a> daemon as
       appropriate.

<b>SYSTEM-WIDE</b> <b>AND</b> <b>USER-LEVEL</b> <b>ALIASING</b>
       The system adminstrator can set up one or more system-wide
       <b>sendmail</b>-style  alias databases.  Users can have <b>sendmail</b>-
       style ~/.<b>forward</b> files.  Mail for <i>name</i> is delivered to the
       alias  <i>name</i>,  to  destinations  in  ~<i>name</i>/.<b>forward</b>, to the
       mailbox owned by the user <i>name</i>, or  it  is  sent  back  as
       undeliverable.

       The  system  administrator can specify a comma/space sepa-
       rated list of  ~/.<b>forward</b>  like  files  through  the  <b>for-</b>
       <b>ward</b><i>_</i><b>path</b>  configuration  parameter.  Upon  delivery,  the
       local delivery agent tries each pathname in the list until
       a file is found.  The <b>forward</b><i>_</i><b>path</b> parameter is subject to
       interpolation of <b>$user</b> (recipient username), <b>$home</b> (recip-
       ient home directory), <b>$shell</b> (recipient shell), <b>$recipient</b>
       (complete  recipient   address),   <b>$extension</b>   (recipient
       address  extension),  <b>$domain</b>  (recipient  domain),  <b>local</b>
       (entire recipient address localpart) and <b>$recipient</b><i>_</i><b>delim-</b>
       <b>iter.</b>  The  forms  <i>${name?value}</i>  and <i>${name:value}</i> expand
       conditionally to <i>value</i> when <i>$name</i>  is  (is  not)  defined.
       Characters  that  may have special meaning to the shell or
       file system are replaced  by  underscores.   The  list  of
       acceptable characters is specified with the <b>forward</b><i>_</i><b>expan-</b>
       <b>sion</b><i>_</i><b>filter</b> configuration parameter.

       An alias or ~/.<b>forward</b> file may list  any  combination  of
       external   commands,  destination  file  names,  <b>:include:</b>
       directives, or mail addresses.  See <a href="aliases.5.html"><b>aliases</b>(5)</a> for a  pre-
       cise  description. Each line in a user's .<b>forward</b> file has
       the same syntax as the right-hand part of an alias.

       When an address is  found  in  its  own  alias  expansion,
       delivery  is  made  to  the  user  instead. When a user is
       listed in the user's own ~/.<b>forward</b> file, delivery is made
       to  the  user's mailbox instead.  An empty ~/.<b>forward</b> file
       means do not forward mail.

       In order to prevent the mail system from using  up  unrea-
       sonable   amounts  of  memory,  input  records  read  from
       <b>:include:</b> or from ~/.<b>forward</b>  files  are  broken  up  into
       chunks of length <b>line</b><i>_</i><b>length</b><i>_</i><b>limit</b>.

       While  expanding aliases, ~/.<b>forward</b> files, and so on, the
       program attempts to avoid duplicate deliveries. The <b>dupli-</b>
       <b>cate</b><i>_</i><b>filter</b><i>_</i><b>limit</b>  configuration parameter limits the num-
       ber of remembered recipients.

<b>MAIL</b> <b>FORWARDING</b>
       For the sake of reliability, forwarded mail is  re-submit-
       ted  as  a new message, so that each recipient has a sepa-
       rate on-file delivery status record.

       In order to stop mail forwarding loops early, the software
       adds  an  optional  <b>Delivered-To:</b> header with the envelope
       recipient address. If mail arrives for a recipient that is
       already  listed  in a <b>Delivered-To:</b> header, the message is
       bounced.

<b>MAILBOX</b> <b>DELIVERY</b>
       The default per-user mailbox is a file in  the  UNIX  mail
       spool  directory (<b>/var/mail/</b><i>user</i> or <b>/var/spool/mail/</b><i>user</i>);
       the location can be specified with  the  <b>mail</b><i>_</i><b>spool</b><i>_</i><b>direc-</b>
       <b>tory</b>  configuration  parameter. Specify a name ending in <b>/</b>
       for <b>qmail</b>-compatible <b>maildir</b> delivery.

       Alternatively, the per-user mailbox can be a file  in  the
       user's  home  directory  with  a  name  specified  via the
       <b>home</b><i>_</i><b>mailbox</b> configuration parameter. Specify  a  relative
       path name. Specify a name ending in <b>/</b> for <b>qmail</b>-compatible
       <b>maildir</b> delivery.

       Mailbox delivery can be delegated to an  external  command
       specified  with  the <b>mailbox</b><i>_</i><b>command</b> configuration parame-
       ter. The command  executes  with  the  privileges  of  the
       recipient  user  (exception:  in case of delivery as root,
       the   command   executes   with    the    privileges    of
       <b>default</b><i>_</i><b>privs</b>).

       Mailbox  delivery  can be delegated to alternative message
       transports specified in the  <b>master.cf</b>  file.   The  <b>mail-</b>
       <b>box</b><i>_</i><b>transport</b>  configuration parameter specifies a message
       transport that is to be used  for  all  local  recipients,
       regardless  of  whether  they are found in the UNIX passwd
       database.  The <b>fallback</b><i>_</i><b>transport</b>  parameter  specifies  a
       message transport for recipients that are not found in the
       UNIX passwd database.

       In the case of UNIX-style mailbox delivery, the <b>local</b> dae-
       mon prepends a "<b>From</b> <i>sender</i> <i>time_stamp</i>" envelope header to
       each message, prepends an  optional  <b>Delivered-To:</b>  header
       with  the  envelope  recipient address, prepends a <b>Return-</b>
       <b>Path:</b> header with the envelope sender address, prepends  a
       &gt;  character  to lines beginning with "<b>From</b> ", and appends
       an empty line.  The mailbox is locked for exclusive access
       while  delivery  is  in  progress. In case of problems, an
       attempt is made to truncate the mailbox  to  its  original
       length.

       In the case of <b>maildir</b> delivery, the local daemon prepends
       an optional <b>Delivered-To:</b> header with the envelope recipi-
       ent  address  and  prepends a <b>Return-Path:</b> header with the
       envelope sender address.

<b>EXTERNAL</b> <b>COMMAND</b> <b>DELIVERY</b>
       The   <b>allow</b><i>_</i><b>mail</b><i>_</i><b>to</b><i>_</i><b>commands</b>    configuration    parameter
       restricts  delivery to external commands. The default set-
       ting (<b>alias,</b>  <b>forward</b>)  forbids  command  destinations  in
       <b>:include:</b> files.

       The  command  is  executed directly where possible. Assis-
       tance by the shell (<b>/bin/sh</b> on UNIX systems) is used  only
       when  the command contains shell magic characters, or when
       the command invokes a shell built-in command.

       A limited amount of command output  (standard  output  and
       standard  error) is captured for inclusion with non-deliv-
       ery status reports.  A command is forcibly  terminated  if
       it  does  not  complete within <b>command</b><i>_</i><b>time</b><i>_</i><b>limit</b> seconds.
       Command exit status codes are expected to follow the  con-
       ventions defined in &lt;<b>sysexits.h</b>&gt;.

       A  limited amount of message context is exported via envi-
       ronment variables. Characters that may have special  mean-
       ing to the shell are replaced by underscores.  The list of
       acceptable characters is specified with the <b>command</b><i>_</i><b>expan-</b>
       <b>sion</b><i>_</i><b>filter</b> configuration parameter.

       <b>SHELL</b>  The recipient user's login shell.

       <b>HOME</b>   The recipient user's home directory.

       <b>USER</b>   The bare recipient name.

       <b>EXTENSION</b>
              The optional recipient address extension.

       <b>DOMAIN</b> The recipient address domain part.

       <b>LOGNAME</b>
              The bare recipient name.

       <b>LOCAL</b>  The entire recipient address localpart (text to the
              left of the rightmost @ character).

       <b>RECIPIENT</b>
              The entire recipient address.

       The <b>PATH</b> environment variable is always reset to a system-
       dependent default path, and the <b>TZ</b> (time zone) environment
       variable is always passed on without change.

       The current working directory is the mail queue directory.

       The <b>local</b> daemon prepends a "<b>From</b> <i>sender</i> <i>time_stamp</i>" enve-
       lope header to each message, prepends an  optional  <b>Deliv-</b>
       <b>ered-To:</b>  header  with  the  recipient  envelope  address,
       prepends a <b>Return-Path:</b> header with  the  sender  envelope
       address, and appends no empty line.

<b>EXTERNAL</b> <b>FILE</b> <b>DELIVERY</b>
       The  delivery  format  depends on the destination filename
       syntax.  The default is to use UNIX-style mailbox  format.
       Specify  a  name  ending in <b>/</b> for <b>qmail</b>-compatible <b>maildir</b>
       delivery.

       The <b>allow</b><i>_</i><b>mail</b><i>_</i><b>to</b><i>_</i><b>files</b> configuration parameter  restricts
       delivery  to  external  files. The default setting (<b>alias,</b>
       <b>forward</b>) forbids file destinations in <b>:include:</b> files.

       In the case of UNIX-style mailbox delivery, the <b>local</b> dae-
       mon prepends a "<b>From</b> <i>sender</i> <i>time_stamp</i>" envelope header to
       each message, prepends an  optional  <b>Delivered-To:</b>  header
       with  the recipient envelope address, prepends a &gt; charac-
       ter to lines beginning with "<b>From</b> ", and appends an  empty
       line.   The  envelope  sender  address is available in the
       <b>Return-Path:</b> header.  When the destination  is  a  regular
       file,  it is locked for exclusive access while delivery is
       in progress. In case of problems, an attempt  is  made  to
       truncate a regular file to its original length.

       In the case of <b>maildir</b> delivery, the local daemon prepends
       an optional <b>Delivered-To:</b> header with the envelope recipi-
       ent  address.  The envelope sender address is available in
       the <b>Return-Path:</b> header.

<b>ADDRESS</b> <b>EXTENSION</b>
       The optional <b>recipient</b><i>_</i><b>delimiter</b>  configuration  parameter
       specifies  how  to  separate address extensions from local
       recipient names.

       For example, with  "<b>recipient</b><i>_</i><b>delimiter</b>  <b>=</b>  <b>+</b>",  mail  for
       <i>name</i>+<i>foo</i>  is  delivered  to  the  alias <i>name</i>+<i>foo</i> or to the
       alias <i>name</i>, to  the  destinations  listed  in  ~<i>name</i>/.<b>for-</b>
       <b>ward</b>+<i>foo</i> or in ~<i>name</i>/.<b>forward</b>, to the mailbox owned by the
       user <i>name</i>, or it is sent back as undeliverable.

       In all cases the <b>local</b> daemon prepends an optional `<b>Deliv-</b>
       <b>ered-To:</b> <i>name</i>+<i>foo</i>' header line.

<b>DELIVERY</b> <b>RIGHTS</b>
       Deliveries  to  external  files  and external commands are
       made with the rights of the receiving user on whose behalf
       the  delivery  is made.  In the absence of a user context,
       the <b>local</b> daemon uses the owner rights  of  the  <b>:include:</b>
       file or alias database.  When those files are owned by the
       superuser, delivery is made with the rights specified with
       the <b>default</b><i>_</i><b>privs</b> configuration parameter.

<b>STANDARDS</b>
       <a href="http://www.faqs.org/rfcs/rfc822.html">RFC 822</a> (ARPA Internet Text Messages)

<b>DIAGNOSTICS</b>
       Problems  and transactions are logged to <b>syslogd</b>(8).  Cor-
       rupted message files are marked so that the queue  manager
       can move them to the <b>corrupt</b> queue afterwards.

       Depending  on the setting of the <b>notify</b><i>_</i><b>classes</b> parameter,
       the postmaster is notified of bounces and of  other  trou-
       ble.

<b>BUGS</b>
       For  security  reasons,  the  message  delivery  status of
       external commands or of external  files  is  never  check-
       pointed to file. As a result, the program may occasionally
       deliver more than once to a command or external file. Bet-
       ter safe than sorry.

       Mutually-recursive  aliases  or  ~/.<b>forward</b>  files are not
       detected early.  The resulting  mail  forwarding  loop  is
       broken by the use of the <b>Delivered-To:</b> message header.

<b>CONFIGURATION</b> <b>PARAMETERS</b>
       The  following  <b>main.cf</b> parameters are especially relevant
       to this program. See the Postfix <b>main.cf</b> file  for  syntax
       details  and  for  default  values. Use the <b>postfix</b> <b>reload</b>
       command after a configuration change.

<b>Miscellaneous</b>
       <b>alias</b><i>_</i><b>maps</b>
              List of alias databases.

       <b>biff</b>   Enable or disable notification of new mail via  the
              <b>comsat</b> network service.

       <b>expand</b><i>_</i><b>owner</b><i>_</i><b>alias</b>
              When delivering to an alias that has an owner- com-
              panion alias, set the envelope  sender  address  to
              the  right-hand  side  of  the owner alias, instead
              using of the left-hand side address.

       <b>export</b><i>_</i><b>environment</b>
              List of names of environment parameters that can be
              exported to non-Postfix processes.

       <b>forward</b><i>_</i><b>path</b>
              Search list for .forward files.  The names are sub-
              ject to <i>$name</i> expansion.

       <b>local</b><i>_</i><b>command</b><i>_</i><b>shell</b>
              Shell to use for external  command  execution  (for
              example,  /some/where/smrsh  -c).   When a shell is
              specified, it is invoked even when the command con-
              tains  no  shell  built-in commands or meta charac-
              ters.

       <b>owner</b><i>_</i><b>request</b><i>_</i><b>special</b>
              Give special treatment to <b>owner-</b><i>xxx</i> and <i>xxx</i><b>-request</b>
              addresses.

       <b>prepend</b><i>_</i><b>delivered</b><i>_</i><b>header</b>
              Prepend   an  optional  <b>Delivered-To:</b>  header  upon
              external forwarding, delivery to command  or  file.
              Specify  zero  or  more of: <b>command,</b> <b>file,</b> <b>forward</b>.
              Turning off <b>Delivered-To:</b> when forwarding  mail  is
              not recommended.

       <b>recipient</b><i>_</i><b>delimiter</b>
              Separator between username and address extension.

       <b>require</b><i>_</i><b>home</b><i>_</i><b>directory</b>
              Require that a recipient's home directory is acces-
              sible by the recipient before attempting  delivery.
              Defer delivery otherwise.

<b>Mailbox</b> <b>delivery</b>
       <b>fallback</b><i>_</i><b>transport</b>
              Message transport for recipients that are not found
              in the UNIX passwd database.  This parameter  over-
              rides <b>luser</b><i>_</i><b>relay</b>.

       <b>home</b><i>_</i><b>mailbox</b>
              Pathname  of  a  mailbox  relative to a user's home
              directory.  Specify a path ending in <b>/</b> for maildir-
              style delivery.

       <b>luser</b><i>_</i><b>relay</b>
              Destination  (<i>@domain</i>  or <i>address</i>) for non-existent
              users.  The <i>address</i> is subjected  to  <i>$name</i>  expan-
              sion.

       <b>mail</b><i>_</i><b>spool</b><i>_</i><b>directory</b>
              Directory  with  UNIX-style  mailboxes. The default
              pathname is system dependent.  Specify a path  end-
              ing in <b>/</b> for maildir-style delivery.

       <b>mailbox</b><i>_</i><b>command</b>
              External  command  to use for mailbox delivery. The
              command  executes  with  the  recipient  privileges
              (exception:  root).  The string is subject to $name
              expansions.

       <b>mailbox</b><i>_</i><b>command</b><i>_</i><b>maps</b>
              Lookup tables with per-recipient external  commands
              to  use  for  mailbox delivery. Behavior is as with
              <b>mailbox</b><i>_</i><b>command</b>.

       <b>mailbox</b><i>_</i><b>transport</b>
              Message transport to use for  mailbox  delivery  to
              all local recipients, whether or not they are found
              in the UNIX passwd database.  This parameter  over-
              rides  all other configuration parameters that con-
              trol mailbox delivery, including <b>luser</b><i>_</i><b>relay</b>.

<b>Locking</b> <b>controls</b>
       <b>deliver</b><i>_</i><b>lock</b><i>_</i><b>attempts</b>
              Limit the number of attempts to acquire  an  exclu-
              sive lock on a mailbox or external file.

       <b>deliver</b><i>_</i><b>lock</b><i>_</i><b>delay</b>
              Time  in  seconds  between  successive  attempts to
              acquire an exclusive lock.

       <b>stale</b><i>_</i><b>lock</b><i>_</i><b>time</b>
              Limit the time after which a stale lock is removed.

       <b>mailbox</b><i>_</i><b>delivery</b><i>_</i><b>lock</b>
              What  file locking method(s) to use when delivering
              to a UNIX-style mailbox.  The  default  setting  is
              system  dependent.   For  a  list of available file
              locking methods, use the <b>postconf</b> <b>-l</b> command.

<b>Resource</b> <b>controls</b>
       <b>command</b><i>_</i><b>time</b><i>_</i><b>limit</b>
              Limit the amount of time for delivery  to  external
              command.

       <b>duplicate</b><i>_</i><b>filter</b><i>_</i><b>limit</b>
              Limit  the size of the duplicate filter for results
              from alias etc. expansion.

       <b>line</b><i>_</i><b>length</b><i>_</i><b>limit</b>
              Limit the amount of memory used  for  processing  a
              partial input line.

       <b>local</b><i>_</i><b>destination</b><i>_</i><b>concurrency</b><i>_</i><b>limit</b>
              Limit the number of parallel deliveries to the same
              user.   The  default  limit  is  taken   from   the
              <b>default</b><i>_</i><b>destination</b><i>_</i><b>concurrency</b><i>_</i><b>limit</b> parameter.

       <b>local</b><i>_</i><b>destination</b><i>_</i><b>recipient</b><i>_</i><b>limit</b>
              Limit  the  number of recipients per message deliv-
              ery.   The  default  limit  is   taken   from   the
              <b>default</b><i>_</i><b>destination</b><i>_</i><b>recipient</b><i>_</i><b>limit</b> parameter.

       <b>mailbox</b><i>_</i><b>size</b><i>_</i><b>limit</b>
              Limit  the  size  of  a mailbox etc. file (any file
              that is written to upon delivery).  Set to zero  to
              disable the limit.

<b>Security</b> <b>controls</b>
       <b>allow</b><i>_</i><b>mail</b><i>_</i><b>to</b><i>_</i><b>commands</b>
              Restrict  the  usage  of  mail delivery to external
              command.  Specify zero or more of: <b>alias</b>,  <b>forward</b>,
              <b>include</b>.

       <b>allow</b><i>_</i><b>mail</b><i>_</i><b>to</b><i>_</i><b>files</b>
              Restrict  the  usage  of  mail delivery to external
              file.  Specify zero or  more  of:  <b>alias</b>,  <b>forward</b>,
              <b>include</b>.

       <b>command</b><i>_</i><b>expansion</b><i>_</i><b>filter</b>
              What  characters  are  allowed  to  appear in $name
              expansions of mailbox_command.  Illegal  characters
              are replaced by underscores.

       <b>default</b><i>_</i><b>privs</b>
              Default  rights  for  delivery  to external file or
              command.

       <b>forward</b><i>_</i><b>expansion</b><i>_</i><b>filter</b>
              What characters are  allowed  to  appear  in  $name
              expansions  of forward_path. Illegal characters are
              replaced by underscores.

<b>HISTORY</b>
       The <b>Delivered-To:</b> header appears in the  <b>qmail</b>  system  by
       Daniel Bernstein.

       The  <i>maildir</i>  structure  appears  in  the  <b>qmail</b> system by
       Daniel Bernstein.

<b>SEE</b> <b>ALSO</b>
       <a href="aliases.5.html">aliases(5)</a> format of alias database
       <a href="bounce.8.html">bounce(8)</a> non-delivery status reports
       <a href="postalias.1.html">postalias(1)</a> create/update alias database
       syslogd(8) system logging
       <a href="qmgr.8.html">qmgr(8)</a> queue manager

<b>LICENSE</b>
       The Secure Mailer license must be  distributed  with  this
       software.

<b>AUTHOR(S)</b>
       Wietse Venema
       IBM T.J. Watson Research
       P.O. Box 704
       Yorktown Heights, NY 10598, USA

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