POSTLOCK(1)                                                        POSTLOCK(1)

NAME
       postlock - lock mail folder and execute command

SYNOPSIS
       postlock [-c config_dir] [-l lock_style]
               [-v] file command...

DESCRIPTION
       The  postlock(1)  command locks file for exclusive access,
       and executes command. The  locking  method  is  compatible
       with the Postfix UNIX-style local delivery agent.

       Options:

       -c config_dir
              Read  the  main.cf  configuration file in the named
              directory  instead  of  the  default  configuration
              directory.

       -l lock_style
              Override the locking method specified via the mail-
              box_delivery_lock  configuration   parameter   (see
              below).

       -v     Enable verbose logging for debugging purposes. Mul-
              tiple -v options  make  the  software  increasingly
              verbose.

       Arguments:

       file   A  mailbox  file.  The  user should have read/write
              permission.

       command...
              The command to execute while  file  is  locked  for
              exclusive   access.    The   command   is  executed
              directly, i.e. without interpretation  by  a  shell
              command interpreter.

DIAGNOSTICS
       The  result  status  is  75 (EX_TEMPFAIL) when postlock(1)
       could not perform the requested operation.  Otherwise, the
       exit status is the exit status from the command.

BUGS
       With  remote  file  systems, the ability to acquire a lock
       does not necessarily  eliminate  access  conflicts.  Avoid
       file access by processes running on different machines.

ENVIRONMENT
       MAIL_CONFIG
              Directory with Postfix configuration files.

       MAIL_VERBOSE
              Enable verbose logging for debugging purposes.

CONFIGURATION PARAMETERS
       The  following  main.cf parameters are especially relevant
       to this program.  The text below provides only a parameter
       summary.  See postconf(5) for more details including exam-
       ples.

LOCKING CONTROLS
       deliver_lock_attempts (20)
              The maximal number of attempts to acquire an exclu-
              sive lock on a mailbox file or bounce(8) logfile.

       deliver_lock_delay (1s)
              The  time  between attempts to acquire an exclusive
              lock on a mailbox file or bounce(8) 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) mailbox before
              attempting delivery.

RESOURCE AND RATE CONTROLS
       fork_attempts (5)
              The maximal number of attempts to  fork()  a  child
              process.

       fork_delay (1s)
              The  delay  between  attempts  to  fork()  a  child
              process.

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

SEE ALSO
       postconf(5), configuration parameters

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

                                                                   POSTLOCK(1)