SYNOPSIS

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

DESCRIPTION

       The postlock command locks file for exclusive access, and executes com-
       mand. 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  mailbox_deliv-
              ery_lock configuration parameter (see below).

       -v     Enable  verbose  logging  for  debugging  purposes.  Multiple -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 inter-
              pretation by a shell command interpreter.

DIAGNOSTICS

       The result status is 75 (EX_TEMPFAIL) when postlock 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 neces-
       sarily  eliminate access conflicts. Avoid file access by processes run-
       ning 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  pro-
       gram.   The  text  below  provides  only a parameter summary. See post-
       conf(5) for more details including examples.
       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  con-
              figuration 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)