NAME

Mail::Box::Locker::Flock - lock a folder using kernel file-locking

INHERITANCE

Mail::Box::Locker::Flock
  is a Mail::Box::Locker
  is a Mail::Reporter

SYNOPSIS

See Mail::Box::Locker

DESCRIPTION

The ::Flock object locks the folder by creating an exclusive lock on the file using the kernel's flock facilities. This lock is created on a separate file-handle to the folder file, so not the handle which is reading.

File locking does not work in some situations, for instance for operating systems do not support flock.

METHODS

Constructors

Mail::Box::Locker::Flock->new(OPTIONS)

-Option --Defined in     --Default
 expires  Mail::Box::Locker  1 hour
 file     Mail::Box::Locker  undef
 folder   Mail::Box::Locker  <undef>
 log      Mail::Reporter   'WARNINGS'
 method   Mail::Box::Locker  'FLOCK'
 timeout  Mail::Box::Locker  10 seconds
 trace    Mail::Reporter   'WARNINGS'

expires => SECONDS

file => FILENAME

folder => FOLDER

log => LEVEL

method => STRING|CLASS|ARRAY

timeout => SECONDS|'NOTIMEOUT'

trace => LEVEL

The Locker

$obj->filename([FILENAME])

See "The Locker" in Mail::Box::Locker

$obj->folder([FOLDER])

See "The Locker" in Mail::Box::Locker

$obj->name()

See "The Locker" in Mail::Box::Locker

Locking

$obj->hasLock()

See "Locking" in Mail::Box::Locker

$obj->isLocked()

$obj->lock()

$obj->unlock()

See "Locking" in Mail::Box::Locker

Error handling

$obj->AUTOLOAD()

See "Error handling" in Mail::Reporter

$obj->addReport(OBJECT)

See "Error handling" in Mail::Reporter

$obj->defaultTrace([LEVEL]|[LOGLEVEL, TRACELEVEL]|[LEVEL, CALLBACK])

Mail::Box::Locker::Flock->defaultTrace([LEVEL]|[LOGLEVEL, TRACELEVEL]|[LEVEL, CALLBACK])

See "Error handling" in Mail::Reporter

$obj->errors()

See "Error handling" in Mail::Reporter

$obj->log([LEVEL [,STRINGS]])

Mail::Box::Locker::Flock->log([LEVEL [,STRINGS]])

See "Error handling" in Mail::Reporter

$obj->logPriority(LEVEL)

Mail::Box::Locker::Flock->logPriority(LEVEL)

See "Error handling" in Mail::Reporter

$obj->logSettings()

See "Error handling" in Mail::Reporter

$obj->notImplemented()

See "Error handling" in Mail::Reporter

$obj->report([LEVEL])

See "Error handling" in Mail::Reporter

$obj->reportAll([LEVEL])

See "Error handling" in Mail::Reporter

$obj->trace([LEVEL])

See "Error handling" in Mail::Reporter

$obj->warnings()

See "Error handling" in Mail::Reporter

Cleanup

$obj->DESTROY()

See "Cleanup" in Mail::Box::Locker

$obj->inGlobalDestruction()

See "Cleanup" in Mail::Reporter

DIAGNOSTICS

Warning: Folder $folder already flocked

The folder is already locked, but you attempt to lock it again. The behavior of double flock's is platform dependend, and therefore should not be attempted. The second lock is ignored (but the unlock isn't)

Error: Package $package does not implement $method.

Fatal error: the specific package (or one of its superclasses) does not implement this method where it should. This message means that some other related classes do implement this method however the class at hand does not. Probably you should investigate this and probably inform the author of the package.

Error: Unable to check lock file $filename for $folder: $!

To check whether the filename is used to flock a folder, the file must be opened. Apparently this fails, which does not mean that the folder is locked neither that it is unlocked.

Error: Unable to open flock file $filename for $folder: $!

For flock-ing a folder it must be opened, which does not succeed for the specified reason.

Error: Will never get a flock at $filename for $folder: $!

Tried to flock the folder, but it did not succeed. The error code received from the OS indicates that it will not succeed ever, so we do not need to try again.

SEE ALSO

This module is part of Mail-Box distribution version 2.105, built on May 07, 2012. Website: http://perl.overmeer.net/mailbox/

LICENSE

Copyrights 2001-2012 by [Mark Overmeer]. For other contributors see ChangeLog.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See http://www.perl.com/perl/misc/Artistic.html