Unix/Linux Go Back    


RedHat 9 (Linux i386) - man page for pipe (redhat section 8)

Linux & Unix Commands - Search Man Pages
Man Page or Keyword Search:   man
Select Man Page Set:       apropos Keyword Search (sections above)


PIPE(8) 										  PIPE(8)

NAME
       pipe - Postfix delivery to external command

SYNOPSIS
       pipe [generic Postfix daemon options] command_attributes...

DESCRIPTION
       The  pipe  daemon processes requests from the Postfix queue manager to deliver messages to
       external commands.  This program expects to be run from the master(8) process manager.

       Message attributes such as sender address, recipient address and next-hop host name can be
       specified  as  command-line  macros  that are expanded before the external command is exe-
       cuted.

       The pipe 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 bounce(8) or defer(8) daemon as appropriate.

SINGLE-RECIPIENT DELIVERY
       Some external commands cannot handle more than one recipient per delivery  request.  Exam-
       ples of such transports are pagers, fax machines, and so on.

       To prevent Postfix from sending multiple recipients per delivery request, specify

	   transport_destination_recipient_limit = 1

       in  the Postfix main.cf file, where transport is the name in the first column of the Post-
       fix master.cf entry for the pipe-based delivery transport.

COMMAND ATTRIBUTE SYNTAX
       The external command attributes are given in the master.cf file at the end  of  a  service
       definition.  The syntax is as follows:

       flags=BFRhqu.> (optional)
	      Optional message processing flags. By default, a message is copied unchanged.

	      B      Append  a	blank  line  at the end of each message. This is required by some
		     mail user agents that recognize "From " lines only when preceded by a  blank
		     line.

	      F      Prepend  a  "From sender time_stamp" envelope header to the message content.
		     This is expected by, for example, UUCP software.

	      R      Prepend a Return-Path: message header with the envelope sender address.

	      h      Fold the command-line $recipient domain name and $nexthop host name to lower
		     case.  This is recommended for delivery via UUCP.

	      q      Quote  white  space and other special characters in the command-line $sender
		     and $recipient address localparts (text to the  left  of  the  right-most	@
		     character),  according  to an 8-bit transparent version of RFC 822.  This is
		     recommended for delivery via UUCP or BSMTP.

		     The result is compatible with the address parsing of command-line recipients
		     by the Postfix sendmail mail submission command.

		     The  q  flag affects only entire addresses, not the partial address informa-
		     tion from the $user, $extension or $mailbox command-line macros.

	      u      Fold the command-line $recipient address localpart (text to the left of  the
		     right-most @ character) to lower case.  This is recommended for delivery via
		     UUCP.

	      .      Prepend . to lines starting with ".". This is needed by, for example,  BSMTP
		     software.

	      >      Prepend  > to lines starting with "From ". This is expected by, for example,
		     UUCP software.

       user=username (required)

       user=username:groupname
	      The external command is executed with the rights of the  specified  username.   The
	      software	refuses  to execute commands with root privileges, or with the privileges
	      of the mail system owner. If groupname is specified, the corresponding group ID  is
	      used instead of the group ID of username.

       eol=string (default: \n)
	      The  output  record delimiter. Typically one would use either \r\n or \n. The usual
	      C-style backslash escape sequences are recognized: \a \b \f \n \r \t \v \octal  and
	      \\.

       size=size_limit (optional)
	      Messages	greater  in  size  than this limit (in bytes) will be bounced back to the
	      sender.

       argv=command... (required)
	      The command to be executed. This must be specified as the last  command  attribute.
	      The command is executed directly, i.e. without interpretation of shell meta charac-
	      ters by a shell command interpreter.

	      In the command argument vector, the following macros are	recognized  and  replaced
	      with corresponding information from the Postfix queue manager delivery request:

	      ${extension}
		     This  macro expands to the extension part of a recipient address.	For exam-
		     ple, with an address user+foo@domain the extension is foo.

		     A command-line argument that contains ${extension} expands into as many com-
		     mand-line arguments as there are recipients.

		     This information is modified by the u flag for case folding.

	      ${mailbox}
		     This  macro  expands to the complete local part of a recipient address.  For
		     example, with an address user+foo@domain the mailbox is user+foo.

		     A command-line argument that contains ${mailbox} expands into as  many  com-
		     mand-line arguments as there are recipients.

		     This information is modified by the u flag for case folding.

	      ${nexthop}
		     This macro expands to the next-hop hostname.

		     This information is modified by the h flag for case folding.

	      ${recipient}
		     This macro expands to the complete recipient address.

		     A command-line argument that contains ${recipient} expands into as many com-
		     mand-line arguments as there are recipients.

		     This information is modified by the hqu flags for quoting and case folding.

	      ${sender}
		     This macro expands to the envelope sender address.

		     This information is modified by the q flag for quoting.

	      ${size}
		     This macro expands to Postfix's idea  of  the  message  size,  which  is  an
		     approximation of the size of the message as delivered.

	      ${user}
		     This  macro  expands to the username part of a recipient address.	For exam-
		     ple, with an address user+foo@domain the username part is user.

		     A command-line argument that contains ${user} expands into as many  command-
		     line arguments as there are recipients.

		     This information is modified by the u flag for case folding.

       In addition to the form ${name}, the forms $name and $(name) are also recognized.  Specify
       $$ where a single $ is wanted.

DIAGNOSTICS
       Command exit status codes are expected to follow the conventions defined in <sysexits.h>.

       Problems and transactions are logged to syslogd(8).  Corrupted message files are marked so
       that the queue manager can move them to the corrupt queue for further inspection.

SECURITY
       This program needs a dual personality 1) to access the private Postfix queue and IPC mech-
       anisms, and 2) to execute external commands as the specified user. It is  therefore  secu-
       rity sensitive.

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

Miscellaneous
       export_environment
	      List  of	names  of environment parameters that can be exported to non-Postfix pro-
	      cesses.

       mail_owner
	      The process privileges used while not running an external command.

Resource controls
       In the text below, transport is the first field in a master.cf entry.

       transport_destination_concurrency_limit
	      Limit the number of parallel deliveries to the same destination, for  delivery  via
	      the  named  transport. The default limit is taken from the default_destination_con-
	      currency_limit parameter.  The limit is enforced by the Postfix queue manager.

       transport_destination_recipient_limit
	      Limit the number of recipients per message delivery, for	delivery  via  the  named
	      transport.  The default limit is taken from the default_destination_recipient_limit
	      parameter.  The limit is enforced by the Postfix queue manager.

       transport_time_limit
	      Limit the time for delivery to external command, for delivery via the named  trans-
	      port.  The default limit is taken from the command_time_limit parameter.	The limit
	      is enforced by the Postfix queue manager.

SEE ALSO
       bounce(8) non-delivery status reports
       master(8) process manager
       qmgr(8) queue manager
       syslogd(8) system logging

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

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

											  PIPE(8)
Unix & Linux Commands & Man Pages : ©2000 - 2018 Unix and Linux Forums


All times are GMT -4. The time now is 04:58 AM.