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
mailbox_delivery_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
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 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.
