man > postlock(1)

POSTLOCK(1)                            General Commands Manual                           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 con‐
              figuration directory.

       -l lock_style
              Override  the locking method specified via the mailbox_delivery_lock configuration pa‐
              rameter (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 exe‐
              cuted 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 opera‐
       tion.  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 examples.

LOCKING CONTROLS
       deliver_lock_attempts (20)
              The  maximal  number  of  attempts  to  acquire an exclusive 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.

       import_environment (see 'postconf -d' output)
              The  list of environment parameters that a privileged Postfix process will import from
              a non-Postfix parent process, or name=value environment overrides.

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

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



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