POSTLOCK(1)                                                        POSTLOCK(1)



NAME
       postlock - lock mail folder and execute command

SYNOPSIS
       postlock [-c configdir] [-l lockstyle]
               [-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 configdir
              Read  the  main.cf  configuration  file  in  the named directory
              instead of the default configuration directory.

       -l lockstyle
              Override the locking method  specified  via  the  mailboxdeliv-
              erylock 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 (EXTEMPFAIL) 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
       MAILCONFIG
              Directory with Postfix configuration files.

       MAILVERBOSE
              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.

LOCKING CONTROLS
       deliverlockattempts (200)
              The maximal number of attempts to acquire an exclusive lock on a
              mailbox file or bounce(8) logfile.

       deliverlockdelay (1s)
              The  time  between  attempts  to  acquire an exclusive lock on a
              mailbox file or bounce(8) logfile.

       stalelocktime (50000s)
              The time after which  a  stale  exclusive  mailbox  lockfile  is
              removed.

       mailboxdeliverylock (see ''postconf -d'' output)
              How  to  lock  a  UNIX-style  local(8) mailbox before attempting
              delivery.

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

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

MISCELANEOUS CONTROLS
       configdirectory (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)