NAME

Mail::Box::Locker::NFS - lock a folder with a separate file, NFS-safe

INHERITANCE

Mail::Box::Locker::NFS
  is a Mail::Box::Locker
  is a Mail::Reporter

SYNOPSIS

See Mail::Box::Locker

DESCRIPTION

Like the ::DotLock locker, but then in an NFS-safe fashion. Over NFS, the creation of a file is not atomic. The ::DotLock locker depends on an atomic open system call, hence in not usable to lock a folder which accessed over NFS. The ::NFS locker is therefore more complicated (so therefore slower), but will work for NFS --and for local disks as well.

METHODS

Constructors

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

    Option --Defined in     --Default
    expires  Mail::Box::Locker  1 hour
    file     Mail::Box::Locker  undef
    folder   Mail::Box::Locker  <required>
    log      Mail::Reporter   'WARNINGS'
    method   Mail::Box::Locker  'NFS'
    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])

$obj->folder

$obj->name

Locking

$obj->hasLock

$obj->isLocked

$obj->lock

$obj->unlock

Error handling

$obj->AUTOLOAD

$obj->addReport(OBJECT)

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

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

$obj->errors

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

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

$obj->logPriority(LEVEL)

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

$obj->logSettings

$obj->notImplemented

$obj->report([LEVEL])

$obj->reportAll([LEVEL])

$obj->trace([LEVEL])

$obj->warnings

Cleanup

$obj->DESTROY

$obj->inGlobalDestruction

DIAGNOSTICS

Warning: Folder $folder already locked over nfs

    Do not try to lock the folder when the application already has the lock: it will give you dead-locks.

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.

Warning: Removed expired lockfile $filename.

    A lock file was found which was older than the expiration period as specified with new(timeout). The lock file was succesfully removed.

Error: Unable to remove expired lockfile $lockfile: $!

    A lock file was found which was older than the expiration period as specified with the new(timeout) option. It is impossible to remove that lock file, so we need to wait until it vanishes by some external cause.

SEE ALSO

This module is part of Mail-Box distribution version 2.078, built on November 09, 2007. Website: http://perl.overmeer.net/mailbox/

LICENSE

Copyrights 2001-2007 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