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])

See Mail::Box::Locker/"The Locker"

$obj->folder

See Mail::Box::Locker/"The Locker"

$obj->name

See Mail::Box::Locker/"The Locker"

Locking

$obj->hasLock

See Mail::Box::Locker/"Locking"

$obj->isLocked

See Mail::Box::Locker/"Locking"

$obj->lock

$obj->unlock

See Mail::Box::Locker/"Locking"

Error handling

$obj->AUTOLOAD

See Mail::Reporter/"Error handling"

$obj->addReport(OBJECT)

See Mail::Reporter/"Error handling"

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

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

See Mail::Reporter/"Error handling"

$obj->errors

See Mail::Reporter/"Error handling"

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

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

See Mail::Reporter/"Error handling"

$obj->logPriority(LEVEL)

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

See Mail::Reporter/"Error handling"

$obj->logSettings

See Mail::Reporter/"Error handling"

$obj->notImplemented

See Mail::Reporter/"Error handling"

$obj->report([LEVEL])

See Mail::Reporter/"Error handling"

$obj->reportAll([LEVEL])

See Mail::Reporter/"Error handling"

$obj->trace([LEVEL])

See Mail::Reporter/"Error handling"

$obj->warnings

See Mail::Reporter/"Error handling"

Cleanup

$obj->DESTROY

See Mail::Box::Locker/"Cleanup"

$obj->inGlobalDestruction

See Mail::Reporter/"Cleanup"

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.

LICENSE

Copyrights 2001-2008 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