# local - Postfix local mail delivery - man(8postfix) - [phpMan]

[_LOCAL_(8postfix)](https://www.chedong.com/phpMan.php/man/LOCAL/8postfix/markdown)                                                                      [_LOCAL_(8postfix)](https://www.chedong.com/phpMan.php/man/LOCAL/8postfix/markdown)

## NAME
       local - Postfix local mail delivery

## SYNOPSIS
       **local **[generic Postfix daemon options]

## DESCRIPTION
       The  [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown)  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 [**master**(8)](https://www.chedong.com/phpMan.php/man/master/8/markdown) process manager.

       The [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) 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 status reports
       are sent to the [**bounce**(8)](https://www.chedong.com/phpMan.php/man/bounce/8/markdown), [**defer**(8)](https://www.chedong.com/phpMan.php/man/defer/8/markdown) or [**trace**(8)](https://www.chedong.com/phpMan.php/man/trace/8/markdown) daemon as appropriate.

## CASE FOLDING
       All delivery decisions are made using the bare recipient name (i.e. the  address  localpart),
       folded to lower case.  See also under ADDRESS EXTENSION below for a few exceptions.

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

       The  system  administrator  can specify a comma/space separated list of ~/.**forward **like files
       through the **forward_path **configuration parameter. Upon delivery,  the  local  delivery  agent
       tries each pathname in the list until a file is found.

       Delivery via ~/.**forward **files is done with the privileges of the recipient.  Thus, ~/.**forward**
       like  files must be readable by the recipient, and their parent directory needs to have "exe‐
       cute" permission for the recipient.

       The **forward_path **parameter is subject to interpolation of **$user **(recipient  username),  **$home**
       (recipient  home  directory),  **$shell  **(recipient  shell), **$recipient **(complete recipient ad‐
       dress), **$extension **(recipient address extension), **$domain **(recipient domain), **$local  **(entire
       recipient   address   localpart)   and  **$recipient_delimiter.  **The  forms  _${name?value}_  and
       _${name?{value}}_ (Postfix 3.0 and later) expand conditionally to _value_ when _$name_ is  defined,
       and  the  forms _${name:value}_ _${name:{value}}_ (Postfix 3.0 and later) expand conditionally to
       _value_ when _$name_ is not defined.  The form _${name?{value1}:{value2}}_ (Postfix 3.0 and  later)
       expands  conditionally  to _value1_ when _$name_ is defined, or _value2_ otherwise. Characters that
       may have special meaning to the shell or file system are replaced with underscores. The  list
       of acceptable characters is specified with the **forward_expansion_filter **configuration parame‐
       ter.

       An  alias  or ~/.**forward **file may list any combination of external commands, destination file
       names, **:include: **directives, or mail addresses.  See [**aliases**(5)](https://www.chedong.com/phpMan.php/man/aliases/5/markdown) for  a  precise  description.
       Each line in a user's .**forward **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 ~/.**forward **file, delivery is made to the user's mail‐
       box instead.  An empty ~/.**forward **file means do not forward mail.

       In order to prevent the mail system from using  up  unreasonable  amounts  of  memory,  input
       records  read  from  **:include:  **or  from ~/.**forward **files are broken up into chunks of length
       **line_length_limit**.

       While expanding aliases, ~/.**forward **files, and so on, the program attempts to avoid duplicate
       deliveries. The **duplicate_filter_limit **configuration parameter limits the  number  of  remem‐
       bered recipients.

## MAIL FORWARDING
       For  the  sake  of reliability, forwarded mail is re-submitted as a new message, so that each
       recipient has a separate on-file delivery status record.

       In order to stop mail forwarding loops early, the software  adds  an  optional  **Delivered-To:**
       header with the final envelope recipient address. If mail arrives for a recipient that is al‐
       ready listed in a **Delivered-To: **header, the message is bounced.

## MAILBOX DELIVERY
       The  default  per-user  mailbox is a file in the UNIX mail spool directory (**/var/mail/_**user_ or
       **/var/spool/mail/_**user_); the location can be specified with the **mail_spool_directory **configura‐
       tion parameter. Specify a name ending in **/ **for **qmail**-compatible **maildir **delivery.

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

       Mailbox  delivery  can  be  delegated  to an external command specified with the **mailbox_com‐**
       **mand_maps **and **mailbox_command **configuration parameters. The command executes with the  privi‐
       leges  of the recipient user (exceptions: secondary groups are not enabled; in case of deliv‐
       ery as root, the command executes with the privileges of **default_privs**).

       Mailbox delivery can be delegated to alternative message transports  specified  in  the  **mas‐**
       **ter.cf **file.  The **mailbox_transport_maps **and **mailbox_transport **configuration parameters spec‐
       ify  an optional message transport that is to be used for all local recipients, regardless of
       whether they are found in the UNIX passwd database.  The  **fallback_transport_maps  **and  **fall‐**
       **back_transport  **parameters  specify an optional message transport for recipients that are not
       found in the [aliases(5)](https://www.chedong.com/phpMan.php/man/aliases/5/markdown) or UNIX passwd database.

       In the case of UNIX-style mailbox delivery, the  [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown)  daemon  prepends  a  "**From  _**sender_
       _time_stamp_"  envelope  header to each message, prepends an **X-Original-To: **header with the re‐
       cipient address as given to Postfix, prepends an optional **Delivered-To: **header with the final
       envelope recipient address, prepends a **Return-Path: **header with the envelope sender  address,
       prepends a **> **character to lines beginning with "**From **", and appends an empty line.  The mail‐
       box is locked for exclusive access while delivery is in progress. In case of problems, an at‐
       tempt is made to truncate the mailbox to its original length.

       In  the  case of **maildir **delivery, the local daemon prepends an optional **Delivered-To: **header
       with the final envelope recipient address, prepends an **X-Original-To: **header with the recipi‐
       ent address as given to Postfix, and prepends a **Return-Path: **header with the envelope  sender
       address.

## EXTERNAL COMMAND DELIVERY
       The  **allow_mail_to_commands  **configuration parameter restricts delivery to external commands.
       The default setting (**alias, forward**) forbids command destinations in **:include: **files.

       Optionally, the process working directory is changed to the path specified with  **command_exe‐**
       **cution_directory  **(Postfix  2.2 and later). Failure to change directory causes mail to be de‐
       ferred.

       The **command_execution_directory **parameter value is subject to interpolation of **$user **(recipi‐
       ent username), **$home **(recipient home directory), **$shell **(recipient shell),  **$recipient  **(com‐
       plete  recipient  address),  **$extension **(recipient address extension), **$domain **(recipient do‐
       main), **$local **(entire recipient  address  localpart)  and  **$recipient_delimiter.   **The  forms
       _${name?value}_  and _${name?{value}}_ (Postfix 3.0 and later) expand conditionally to _value_ when
       _$name_ is defined, and the forms _${name:value}_ and _${name:{value}}_ (Postfix 3.0 and later) ex‐
       pand conditionally to _value_ when _$name_ is not defined.   The  form  _${name?{value1}:{value2}}_
       (Postfix 3.0 and later) expands conditionally to _value1_ when _$name_ is defined, or _value2_ oth‐
       erwise.  Characters  that  may  have special meaning to the shell or file system are replaced
       with underscores. The list of acceptable characters is specified  with  the  **execution_direc‐**
       **tory_expansion_filter **configuration parameter.

       The  command  is  executed  directly where possible. Assistance by the shell (**/bin/sh **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 in‐
       clusion with non-delivery status reports.  A command is forcibly terminated if  it  does  not
       complete within **command_time_limit **seconds.  Command exit status codes are expected to follow
       the conventions defined in <**sysexits.h**>.  Exit status 0 means normal successful completion.

       Postfix  version  2.3  and  later support RFC 3463-style enhanced status codes.  If a command
       terminates with a non-zero exit status, and the command output begins with an enhanced status
       code, this status code takes precedence over the non-zero exit status.

       A limited amount of message context is exported via environment  variables.  Characters  that
       may  have special meaning to the shell are replaced with underscores.  The list of acceptable
       characters is specified with the **command_expansion_filter **configuration parameter.

       **SHELL  **The recipient user's login shell.

       **HOME   **The recipient user's home directory.

       **USER   **The bare recipient name.

       **EXTENSION**
              The optional recipient address extension.

       **DOMAIN **The recipient address domain part.

       **LOGNAME**
              The bare recipient name.

       **LOCAL  **The entire recipient address localpart (text to the left of the  rightmost  @  charac‐
              ter).

       **ORIGINAL_RECIPIENT**
              The  entire  recipient  address, before any address rewriting or aliasing (Postfix 2.5
              and later).

       **RECIPIENT**
              The entire recipient address.

       **SENDER **The entire sender address.

       Additional remote client information is made available via the  following  environment  vari‐
       ables:

       **CLIENT_ADDRESS**
              Remote client network address. Available as of Postfix 2.2.

       **CLIENT_HELO**
              Remote client EHLO command parameter. Available as of Postfix 2.2.

       **CLIENT_HOSTNAME**
              Remote client hostname. Available as of Postfix 2.2.

       **CLIENT_PROTOCOL**
              Remote client protocol. Available as of Postfix 2.2.

       **SASL_METHOD**
              SASL  authentication  method specified in the remote client AUTH command. Available as
              of Postfix 2.2.

       **SASL_SENDER**
              SASL sender address specified in the remote client MAIL FROM command. Available as  of
              Postfix 2.2.

       **SASL_USERNAME**
              SASL  username  specified  in the remote client AUTH command.  Available as of Postfix
              2.2.

       The **PATH **environment variable is always reset to a system-dependent default path,  and  envi‐
       ronment  variables  whose names are blessed by the **export_environment **configuration parameter
       are exported unchanged.

       The current working directory is the mail queue directory.

       The [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) daemon prepends a "**From _**sender_ _time_stamp_"  envelope  header  to  each  message,
       prepends an **X-Original-To: **header with the recipient address as given to Postfix, prepends an
       optional  **Delivered-To:  **header  with  the  final  recipient envelope address, prepends a **Re‐**
       **turn-Path: **header with the sender envelope address, and appends no empty line.

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

       The **allow_mail_to_files **configuration parameter restricts delivery to external files. The de‐
       fault setting (**alias, forward**) forbids file destinations in **:include: **files.

       In  the  case  of  UNIX-style  mailbox  delivery, the [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) daemon prepends a "**From _**sender_
       _time_stamp_" envelope header to each message, prepends an **X-Original-To: **header with  the  re‐
       cipient address as given to Postfix, prepends an optional **Delivered-To: **header with the final
       recipient  envelope  address, prepends a **> **character to lines beginning with "**From **", and ap‐
       pends an empty line.  The envelope sender address is available in  the  **Return-Path:  **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 origi‐
       nal length.

       In the case of **maildir **delivery, the local daemon prepends an optional  **Delivered-To:  **header
       with the final envelope recipient address, and prepends an **X-Original-To: **header with the re‐
       cipient  address  as  given  to Postfix.  The envelope sender address is available in the **Re‐**
       **turn-Path: **header.

## ADDRESS EXTENSION
       The optional **recipient_delimiter **configuration parameter specifies how  to  separate  address
       extensions from local recipient names.

       For  example,  with  "**recipient_delimiter  =  +**", mail for _name_+_foo_ is delivered to the alias
       _name_+_foo_ or to the alias _name_,  to  the  destinations  listed  in  ~_name_/.**forward**+_foo_  or  in
       ~_name_/.**forward**, to the mailbox owned by the user _name_, or it is sent back as undeliverable.

## DELIVERY RIGHTS
       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  [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown)
       daemon  uses  the owner rights of the **:include: **file or alias database.  When those files are
       owned by the superuser, delivery is made with the rights  specified  with  the  **default_privs**
       configuration parameter.

## STANDARDS
       RFC 822 (ARPA Internet Text Messages)
       RFC 3463 (Enhanced status codes)

## DIAGNOSTICS
       Problems  and  transactions are logged to [**syslogd**(8)](https://www.chedong.com/phpMan.php/man/syslogd/8/markdown) or [**postlogd**(8)](https://www.chedong.com/phpMan.php/man/postlogd/8/markdown).  Corrupted message files
       are marked so that the queue manager can move them to the **corrupt **queue afterwards.

       Depending on the setting of the **notify_classes  **parameter,  the  postmaster  is  notified  of
       bounces and of other trouble.

## SECURITY
       The  [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown)  delivery agent needs a dual personality 1) to access the private Postfix queue
       and IPC mechanisms, 2) to impersonate the recipient and deliver to recipient-specified  files
       or commands. It is therefore security sensitive.

       The  [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown)  delivery  agent  disallows  regular  expression  substitution  of  $1  etc. in
       **alias_maps**, because that would open a security hole.

       The [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery agent will silently ignore  requests  to  use  the  [**proxymap**(8)](https://www.chedong.com/phpMan.php/man/proxymap/8/markdown)  server
       within  **alias_maps**. Instead it will open the table directly.  Before Postfix version 2.2, the
       [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery agent will terminate with a fatal error.

## BUGS
       For security reasons, the message delivery status of external commands or of  external  files
       is  never  checkpointed  to file. As a result, the program may occasionally deliver more than
       once to a command or external file. Better safe than sorry.

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

## CONFIGURATION PARAMETERS
       Changes  to **main.cf **are picked up automatically, as [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) processes run for only a limited
       amount of time. Use the command "**postfix reload**" to speed up a change.

       The text below provides only a parameter summary. See [**postconf**(5)](https://www.chedong.com/phpMan.php/man/postconf/5/markdown) for more details  including
       examples.

## COMPATIBILITY CONTROLS
### biff (yes)
              Whether or not to use the local biff service.

### expand_owner_alias (no)
              When delivering to an alias "_aliasname_" that has an "owner-_aliasname_" companion alias,
              set the envelope sender address to the expansion of the "owner-_aliasname_" alias.

### owner_request_special (yes)
              Enable  special treatment for owner-_listname_ entries in the [**aliases**(5)](https://www.chedong.com/phpMan.php/man/aliases/5/markdown) file, and don't
              split owner-_listname_ and _listname_-request address localparts when the recipient_delim‐
              iter is set to "-".

### sun_mailtool_compatibility (no)
              Obsolete SUN mailtool compatibility feature.

       Available in Postfix version 2.3 and later:

### frozen_delivered_to (yes)
              Update  the  [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown)  delivery  agent's  idea  of  the  Delivered-To:  address   (see
              prepend_delivered_header) only once, at the start of a delivery attempt; do not update
              the Delivered-To: address while expanding aliases or .forward files.

       Available in Postfix version 2.5.3 and later:

### strict_mailbox_ownership (yes)
              Defer delivery when a mailbox file is not owned by its recipient.

### reset_owner_alias (no)
              Reset the [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery agent's idea of the owner-alias attribute, when delivering
              mail to a child alias that does not have its own owner alias.

       Available in Postfix version 3.0 and later:

### local_delivery_status_filter ($default_delivery_status_filter)
              Optional  filter for the [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery agent to change the status code or explana‐
              tory text of successful or unsuccessful deliveries.

## DELIVERY METHOD CONTROLS
       The precedence of [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery methods from high to low  is:  aliases,  .forward  files,
       mailbox_transport_maps,  mailbox_transport, mailbox_command_maps, mailbox_command, home_mail‐
       box, mail_spool_directory, fallback_transport_maps, fallback_transport, and luser_relay.

### alias_maps (see 'postconf -d' output)
              The alias databases that are used for [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery.

### forward_path (see 'postconf -d' output)
              The [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery agent search list for finding a .forward file  with  user-speci‐
              fied delivery methods.

### mailbox_transport_maps (empty)
              Optional  lookup  tables with per-recipient message delivery transports to use for **lo‐**
              [**cal**(8)](https://www.chedong.com/phpMan.php/man/cal/8/markdown) mailbox delivery, whether or not the recipients are found in  the  UNIX  passwd
              database.

### mailbox_transport (empty)
              Optional  message  delivery  transport that the [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery agent should use for
              mailbox delivery to all local recipients, whether or not they are found  in  the  UNIX
              passwd database.

### mailbox_command_maps (empty)
              Optional  lookup tables with per-recipient external commands to use for [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) mail‐
              box delivery.

### mailbox_command (empty)
              Optional external command that the [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery agent should use for mailbox  de‐
              livery.

### home_mailbox (empty)
              Optional pathname of a mailbox file relative to a [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) user's home directory.

### mail_spool_directory (see 'postconf -d' output)
              The directory where [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) UNIX-style mailboxes are kept.

### fallback_transport_maps (empty)
              Optional  lookup  tables with per-recipient message delivery transports for recipients
              that the [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery agent could not find in the  [**aliases**(5)](https://www.chedong.com/phpMan.php/man/aliases/5/markdown)  or  UNIX  password
              database.

### fallback_transport (empty)
              Optional  message  delivery  transport that the [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery agent should use for
              names that are not found in the [**aliases**(5)](https://www.chedong.com/phpMan.php/man/aliases/5/markdown) or UNIX password database.

### luser_relay (empty)
              Optional catch-all destination for unknown [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) recipients.

       Available in Postfix version 2.2 and later:

### command_execution_directory (empty)
              The [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery agent working directory for delivery to external commands.

## MAILBOX LOCKING CONTROLS
### deliver_lock_attempts (20)
              The maximal number of attempts to acquire an exclusive  lock  on  a  mailbox  file  or
              [**bounce**(8)](https://www.chedong.com/phpMan.php/man/bounce/8/markdown) logfile.

### deliver_lock_delay (1s)
              The  time between attempts to acquire an exclusive lock on a mailbox file or [**bounce**(8)](https://www.chedong.com/phpMan.php/man/bounce/8/markdown)
              logfile.

### stale_lock_time (500s)
              The time after which a stale exclusive mailbox lockfile is removed.

### mailbox_delivery_lock (see 'postconf -d' output)
              How to lock a UNIX-style [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) mailbox before attempting delivery.

## RESOURCE AND RATE CONTROLS
### command_time_limit (1000s)
              Time limit for delivery to external commands.

### duplicate_filter_limit (1000)
              The maximal number of  addresses  remembered  by  the  address  duplicate  filter  for
              [**aliases**(5)](https://www.chedong.com/phpMan.php/man/aliases/5/markdown) or [**virtual**(5)](https://www.chedong.com/phpMan.php/man/virtual/5/markdown) alias expansion, or for [**showq**(8)](https://www.chedong.com/phpMan.php/man/showq/8/markdown) queue displays.

### mailbox_size_limit (51200000)
              The  maximal  size  of  any  [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown)  individual mailbox or maildir file, or zero (no
              limit).

       Implemented in the [qmgr(8)](https://www.chedong.com/phpMan.php/man/qmgr/8/markdown) daemon:

### local_destination_concurrency_limit (2)
              The maximal number of parallel deliveries via the local mail delivery transport to the
              same recipient (when "local_destination_recipient_limit = 1") or the maximal number of
              parallel deliveries to the same local domain (when  "local_destination_recipient_limit
              > 1").

### local_destination_recipient_limit (1)
              The  maximal  number  of  recipients  per message delivery via the local mail delivery
              transport.

## SECURITY CONTROLS
### allow_mail_to_commands (alias, forward)
              Restrict [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) mail delivery to external commands.

### allow_mail_to_files (alias, forward)
              Restrict [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) mail delivery to external files.

### command_expansion_filter (see 'postconf -d' output)
              Restrict the characters that the [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery agent allows in $name expansions of
              $mailbox_command and $command_execution_directory.

### default_privs (nobody)
              The default rights used by the [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery agent for  delivery  to  an  external
              file or command.

### forward_expansion_filter (see 'postconf -d' output)
              Restrict the characters that the [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery agent allows in $name expansions of
              $forward_path.

       Available in Postfix version 2.2 and later:

### execution_directory_expansion_filter (see 'postconf -d' output)
              Restrict the characters that the [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery agent allows in $name expansions of
              $command_execution_directory.

       Available in Postfix version 2.5.3 and later:

### strict_mailbox_ownership (yes)
              Defer delivery when a mailbox file is not owned by its recipient.

## MISCELLANEOUS CONTROLS
### config_directory (see 'postconf -d' output)
              The default location of the Postfix main.cf and master.cf configuration files.

### daemon_timeout (18000s)
              How  much time a Postfix daemon process may take to handle a request before it is ter‐
              minated by a built-in watchdog timer.

### delay_logging_resolution_limit (2)
              The maximal number of digits after the decimal point  when  logging  sub-second  delay
              values.

### export_environment (see 'postconf -d' output)
              The  list  of  environment variables that a Postfix process will export to non-Postfix
              processes.

### ipc_timeout (3600s)
              The time limit for sending or receiving information  over  an  internal  communication
              channel.

### local_command_shell (empty)
              Optional shell program for [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery to non-Postfix commands.

### max_idle (100s)
              The  maximum  amount of time that an idle Postfix daemon process waits for an incoming
              connection before terminating voluntarily.

### max_use (100)
              The maximal number of incoming connections that a Postfix daemon process will  service
              before terminating voluntarily.

### prepend_delivered_header (command, file, forward)
              The message delivery contexts where the Postfix [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) delivery agent prepends a De‐
              livered-To:  message header with the address that the mail was delivered to.

### process_id (read-only)
              The process ID of a Postfix command or daemon process.

### process_name (read-only)
              The process name of a Postfix command or daemon process.

### propagate_unmatched_extensions (canonical, virtual)
              What address lookup tables copy an address extension from the lookup key to the lookup
              result.

### queue_directory (see 'postconf -d' output)
              The location of the Postfix top-level queue directory.

### recipient_delimiter (empty)
              The  set  of  characters that can separate an email address localpart, user name, or a
              .forward file name from its extension.

### require_home_directory (no)
              Require that a [**local**(8)](https://www.chedong.com/phpMan.php/man/local/8/markdown) recipient's home directory exists before mail delivery is  at‐
              tempted.

### syslog_facility (mail)
              The syslog facility of Postfix logging.

### syslog_name (see 'postconf -d' output)
              A  prefix  that is prepended to the process name in syslog records, so that, for exam‐
              ple, "smtpd" becomes "prefix/smtpd".

       Available in Postfix version 3.3 and later:

### enable_original_recipient (yes)
              Enable support for the original recipient address after an address is rewritten  to  a
              different address (for example with aliasing or with canonical mapping).

### service_name (read-only)
              The master.cf service name of a Postfix daemon process.

       Available in Postfix 3.5 and later:

### info_log_address_format (external)
              The email address form that will be used in non-debug logging (info, warning, etc.).

## FILES
       The following are examples; details differ between systems.
       $HOME/.forward, per-user aliasing
       /etc/aliases, system-wide alias database
       /var/spool/mail, system mailboxes

## SEE ALSO
       [qmgr(8)](https://www.chedong.com/phpMan.php/man/qmgr/8/markdown), queue manager
       [bounce(8)](https://www.chedong.com/phpMan.php/man/bounce/8/markdown), delivery status reports
       [newaliases(1)](https://www.chedong.com/phpMan.php/man/newaliases/1/markdown), create/update alias database
       [postalias(1)](https://www.chedong.com/phpMan.php/man/postalias/1/markdown), create/update alias database
       [aliases(5)](https://www.chedong.com/phpMan.php/man/aliases/5/markdown), format of alias database
       [postconf(5)](https://www.chedong.com/phpMan.php/man/postconf/5/markdown), configuration parameters
       [master(5)](https://www.chedong.com/phpMan.php/man/master/5/markdown), generic daemon options
       [postlogd(8)](https://www.chedong.com/phpMan.php/man/postlogd/8/markdown), Postfix logging
       [syslogd(8)](https://www.chedong.com/phpMan.php/man/syslogd/8/markdown), system logging

## LICENSE
       The Secure Mailer license must be distributed with this software.

## HISTORY
       The **Delivered-To: **message header appears in the **qmail **system by Daniel Bernstein.

       The _maildir_ structure appears in the **qmail **system by Daniel Bernstein.

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

       Wietse Venema
       Google, Inc.
       111 8th Avenue
       New York, NY 10011, USA

                                                                                     [_LOCAL_(8postfix)](https://www.chedong.com/phpMan.php/man/LOCAL/8postfix/markdown)
